Digitala Vetenskapliga Arkivet

Change search
Refine search result
1234567 1 - 50 of 3693
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Abadii, Eyerusalem
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Wastewater Treatment by Partial Nitritation / Anammox -Hydroxyapatite coupled process (PN/A-HAP)2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Nitrogen and phosphorus pollution is still a serious environmental problem and a major threat to sustainable development, as they mainly cause eutrophication. Therefore, increasingly stricter requirements are placed on wastewater treatment plants when it comes to emissions of nutrients. To meet these requirements, it is important to continuously renew and improve the purification processes, thereby reducing the emissions of nutrients to the sea, lakes, and streams. The effect of simultaneous nitrogen removal and phosphorus recycling was investigated in this study, employing a one-step process for partial nitritation/anammox-hydroxyapatite (PN/HAP). An experiment in a laboratory-scale SBR reactor (Sequence Batch Reactor) was performed using wastewater from the side-stream centrate. This study validated results to a certain extent published studies by other researchers. However, they had almost exclusively used synthetic wastewater, unlike the here presented where real wastewater was used. The innovative PN/A-HAP process showed effective nitrogen and phosphorus removal without additional aeration or pH adjustment, which means lower energy consumption, reduced nitrous oxide emissions, and reduced sludge production. The results showed an average nitrogen removal efficiency of 32.84% and an average phosphorus removal efficiency of 71.48%. These results indicate significant potential for sustainable wastewater management for some nitrogen and phosphorus side streams at the treatment plants. However, further research is required on a larger scale to precisely assess the long-term separation efficiency for nitrogen and phosphorus, as well as the scalability and usability of the process under real conditions. 

    This Thesis was performed in the frame of a research project 'Process development of CA-induced HAP (Hydroxyapatite) granulation in nitrogen separation with Anammox' funded by the VA Cluster Mälardalen. 

    Download full text (pdf)
    fulltext
  • 2.
    Abaid, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Evaluation of Jatropha Curcas as future en-ergy crop in some African countries.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Biofuels now days consider as one of the successful alternative to meet the challenges associated with climate change and peak oil, as well as a way for poorer countries to develop an industry in order to enhance social and economic development. In many developing countries and particularly in Africa, this has led to large-scale investments in lands by foreign companies, and as a consequence there has been a debate on whether these actions are environmentally sustainable and whether this kind of activity actually brings economic development. The investments of biofuels in Africa, espe-cially the Jatropha plantations are debatable. Several arguments have been concentrat-ed on development goals, economic issues and environmental concerns. This report evaluates the status of some Jatropha projects in Sudan, Ethiopia, Kenya and Tanza-nia, the outcomes of the report show that biofuels from Jatropha lead to a significant socio -economic benefits by creating many jobs opportunities and improve the stand-ard of living in Africa. However, inadequate funding’s, high investment costs, no clear policies for biodiesel are the most challenging for Jatropha in Africa which need fur-ther mechanisms and ideology by African scientists, leaders, NGOs, farmers and deci-sion makers. In the studied countries, it was reported that the Jatropha produce low yields of oil seeds especially in the marginal lands with no enough water supplies. In Kenya the productivity of Jatropha is very low for large scale- project. Moreover some social and environmental impacts are also seen for Jatropha cultivations in Ethiopia, Kenya and Tanzania. Some Jatropha projects have impacted the food security nega-tively; nevertheless some biofuels experts believe that Jatropha has no any adverse im-pacts on food security since it is inedible and grown on marginal lands. In Ethiopia, the main environmental impacts of Jatropha are related to biodiversity, water quality and quantity. In Kenya, the environmental impacts are related to biodiversity, carbon emissions, water withdrawal, pollution of agro- chemicals usage, deforestation and soil erosion, whereas in Tanzania, the main environmental issues are connected to the change of land use system, impacts on biodiversity and impacts on water resources.

    Download full text (pdf)
    fulltext
  • 3. Abarca, R. R. M.
    et al.
    Gaudio, M. T.
    Chakraborty, S.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Metals toxic pollutants in the environment: Anthropogenic and geological causes and remediation2019In: Current Trends and Future Developments on (Bio-) Membranes: Membranes in Environmental Applications, Elsevier Inc. , 2019, p. 109-124Chapter in book (Other academic)
    Abstract [en]

    Heavy metals are naturally present in nature, but if their concentration is higher than the normal accepted threshold levels, they constitute one of the pollutants that is more difficult to remove and also to rehabilitate the contaminated site by them. There are many heavy-metal pollutants-the most common among them are arsenic (As), chromium (Cr), lead (Pb), mercury (Hg), cadmium (Cd), cobalt (Co), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), and zinc (Zn), along with the less common ones, which produced, for example, by the nuclear process, such as uranium (U)-in different configuration; hence, many possibilities of contamination in the world exist, and they are more difficult to remove.Thus heavy-metal pollution is more and more becoming one of the principal issues of the global interest, because it is common to both industrialized countries and developing countries. These issues are getting hard to be recognized and cannot be followed the simple rules concerning safety and environmental protection, thus fall into the same errors of the already industrialized countries. At the same time, new environment-remediation techniques are developed in the last decade, especially, in these last years. Some of these technologies concern physical or chemical process or effects, such as ion exchanges, flotations, and photocatalysis, while other technologies concern the use of membrane process, especially ultrafiltration or membrane integrated process or hybrid systems, where membranes are generally submerged and used together with another process.In this chapter a review of this problem and some example of technologies for removing and remediation of the environment are reported. 

  • 4.
    Abbott, D. Wade
    et al.
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Aasen, Inga Marie
    SINTEF Ind, Dept Biotechnol & Nanomed, N-7465 Trondheim, Norway..
    Beauchemin, Karen A.
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Gröndahl, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gruninger, Robert
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Hayes, Maria
    Teagasc Food Res Ctr, Food BioSci Dept, Dublin D15 KN3K 15, Ireland..
    Huws, Sharon
    Queens Univ Belfast QUB, Belfast BT7 1NN, Antrim, North Ireland..
    Kenny, David A.
    Anim Biosci Res Ctr, Dunsany 5 PW93, Meath, Ireland..
    Krizsan, Sophie J.
    Swedish Univ Agr Sci, Dept Agr Res Northern Sweden, SE-90183 Umeå, Sweden..
    Kirwan, Stuart E.
    Anim Biosci Res Ctr, Dunsany 5 PW93, Meath, Ireland..
    Lind, Vibeke
    Norwegian Inst Bioecon Res NIBIO, Post Box 115, N-1431 As, Norway..
    Meyer, Ulrich
    Fed Res Inst Anim Hlth, Friedrich Loeffler Inst FLI, Bundesforsch Inst Tiergesundheit, D-38116 Braunschweig, Germany..
    Ramin, Mohammad
    Swedish Univ Agr Sci, Dept Agr Res Northern Sweden, SE-90183 Umeå, Sweden..
    Theodoridou, Katerina
    Queens Univ Belfast QUB, Belfast BT7 1NN, Antrim, North Ireland..
    von Soosten, Dirk
    Fed Res Inst Anim Hlth, Friedrich Loeffler Inst FLI, Bundesforsch Inst Tiergesundheit, D-38116 Braunschweig, Germany..
    Walsh, Pamela J.
    Queens Univ Belfast QUB, Belfast BT7 1NN, Antrim, North Ireland..
    Waters, Sinead
    Anim Biosci Res Ctr, Dunsany 5 PW93, Meath, Ireland..
    Xing, Xiaohui
    Agr & Agri Food Canada, Lethbridge Res & Dev Ctr, 5403-1 Ave South, Lethbridge, AB T1J 4B1, Canada..
    Seaweed and Seaweed Bioactives for Mitigation of Enteric Methane: Challenges and Opportunities2020In: Animals, E-ISSN 2076-2615, Vol. 10, no 12, article id 2432Article, review/survey (Refereed)
    Abstract [en]

    Simple Summary The need to become more efficient in agriculture and the food industry exists parallel to the challenge of climate change. Meat and dairy production is the target of much scrutiny due to methane (CH4) emissions and global warming. On the other hand, it should be noted that two-thirds of the world's agricultural land consists of pastures and permanent grasslands and is used for livestock grazing. This land is predominantly unsuitable for arable purposes but facilitates the production of high-quality human-edible protein in the form of ruminant animal-derived meat and milk. This makes a significant contribution to feeding the world's population. There is a need to reduce CH4 emissions, however, and several approaches are being researched currently. Seaweeds are diverse plants containing bioactives that differ from their terrestrial counterparts and they are increasingly under investigation as a feed supplement for the mitigation of enteric CH4. Seaweeds are rich in bioactives including proteins, carbohydrates and to a lesser extent lipids, saponins, alkaloids and peptides. These bioactives could also play a role as feed ingredients to reduce enteric CH4. This review collates information on seaweeds and seaweed bioactives and their potential to impact on enteric CH4 emissions. Seaweeds contain a myriad of nutrients and bioactives including proteins, carbohydrates and to a lesser extent lipids as well as small molecules including peptides, saponins, alkaloids and pigments. The bioactive bromoform found in the red seaweed Asparagopsis taxiformis has been identified as an agent that can reduce enteric CH4 production from livestock significantly. However, sustainable supply of this seaweed is a problem and there are some concerns over its sustainable production and potential negative environmental impacts on the ozone layer and the health impacts of bromoform. This review collates information on seaweeds and seaweed bioactives and the documented impact on CH4 emissions in vitro and in vivo as well as associated environmental, economic and health impacts.

  • 5.
    Abdo, Aslan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Modeling contingency infiltration scenarios in MODFLOW: Stockholm Bypass and tunnel induced groundwater drawdown2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Subsurface constructions, such as tunnels, create hydrogeological challenges in mitigating risk of subsidence due to groundwater drawdown. Presenting readily made precautionary mitigation plans, such as strategically planned artificial recharge applications, can help effectivise the mitigation process.

    The Bypass Stockholm project comprises of several subsurface constructions which may lower the surrounding groundwater level through tunnel leakage. Risk of land subsidence persists in the nearby urban area of Vinsta, Stockholm, where a groundwater drawdown may cause the clays in the area to experience land subsidence. A hydrogeological modelling approach was used in the area to create strategic artificial infiltration plans that could be employed as a mitigative response to the drop in groundwater head.

    In order to simulate the potential tunnel drainage, a steady state hydrogeological model was built using MODFLOW. A 220 l/s tunnel leakage was then simulated. Four different artificial groundwater infiltration scenarios were then conceptualized and simulated to observe effects on groundwater heads.

    The groundwater levels of the baseline model of the area fit the calibration targets with average absolute deviation of 0.18 m. The tunnel drainage scenario lowered the groundwater level in the till aquifer and bedrock by 0 - 1.5 m and 0.5 - 5 m respectively, with higher drawdowns observed closer to the tunnel. The infiltration scenarios mitigate the groundwater drawdown with different efficacies; proximity to the recharge point, and discharge into the till aquifer were observed to have the highest effect on groundwater recharge in the model. The model could have been improved by improving the data quality surrounding the hydraulic conductivity of the bedrock, as it had the highest effect according to the parameter sensitivity analysis.

    Download full text (pdf)
    fulltext
  • 6. Abiye, T. A.
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Arsenic concentration in groundwater: Archetypal study from South Africa2019In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 9, article id 100246Article in journal (Refereed)
    Abstract [en]

    South Africa does not have significant surface water resources, which is often easily affected by unpredictable and rapidly changing climatic variables, due to its location in the arid and semi-arid climatic setting. In large part of the country, groundwater from weathered and fractured crystalline rocks plays pivotal role in sustaining the livelihood, often it contains toxic metals released from the host rocks. The host rocks that are responsible for arsenic release in groundwater are primarily enriched due to metamorphism and igneous processes that resulted in the enrichment of economic minerals. Preliminary assessment indicates that the main arsenic containing minerals are arsenopyrite (FeAsS), arsenical oxide, sulpharsenide, arsenopyritical reefs, leucopyrite, löllingite (FeAs2) and scorodite (FeAsO4·2H2O). Owing to the release of arsenic from highly mineralized rocks that constitute the aquifers, arsenic concentration in the groundwater reaches up to 253 μg/L (Namaqualand), 6150 μg/L (west of Johannesburg), about 500 μg/L in the Karoo aquifers, considerably higher than the WHO guideline value of 10 μg/L. Acid mine drainage from coal and gold mining is also found to be an important source of arsenic and other toxic metals in groundwater.

  • 7.
    Abraham, Jonatan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Strand, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Reseavdrag: En analys av ett arbetsmarknadspolitiskt styrmedel ur ett hållbarhetsperspektiv2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The ability to make tax deductions on travel expenses have been present in Sweden since the late 1920s. The main purpose of the state subsidy has been to improve the mobility in the label market. However, in recent years there has been a heated debate as to if the subsidy is truly socio-economically sustainable or not. The favoritism of car users has also made the matter a question of ecological sustainability.

    The aim of this essay is to analyse and provide general knowledge of the swedish system of deductible travel expenses. The text is divided into four major parts:

    • A litterature review presenting the history of the subsidy, previous research, and the current political debate.
    • A questionnaire survey where the general public’s opinion of tax-deductible travel expenses is examined. 
    • A discussion of possible adjustments of the different parameters of the system, where the most optimal ammendment is chosen
    • An analysis of 3 different scenarios; keeping the current system, using the ammended system obtained in the calibration, and removing the system.

    From the results we could conclude that an ammended system would be noticeably more socio-economically viable and ecologically sustainable, compared with the current system. However, a complete removal of the system would be the most optimal. In addition, the questionnaire surveys results shows that the public is mostly positive to travel deductions. However, it was apparent that the views of many could shift completely, when presenting facts.

    Download full text (pdf)
    fulltext
  • 8.
    Abrishami, Sina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Assessment of Urban Metabolism of Stockholm Royal Seaport: Through the Enhanced Economy Wide Material Flow Accounting Framework2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Material flows in Urban Metabolism play a key role for the purpose of building urban areas and growing the economy. There is lack of standard method for accounting of material flows within and across the boundaries of urban systems. This thesis aims to assess the Urban Metabolism of small-scale urban area through the application of the Economic Wide Material Flow Analysis and enhance the scope of the method by adding water flows, which could potentially become a basis for the development of the method in the future. First, the application of the Economic Wide Material Flow Analysis in urban areas was studied through a literature review and then the enhanced Economic Wide Material Flow Analysis was applied to Stockholm Royal Seaport using bottom-up data. Using bottom-up data resulted in detailed information, however, full comparison between urban areas was not possible due to data gaps. The results showed the importance of the method for enhancing Urban Metabolism analysis and amending resource management. Spotting available secondary and recycled resources in the socioeconomic system as a part of application of the method is beneficial to sustain the natural resources use. Since still the method is developing for small-scale urban areas, a mixture of this method and other recommended methods by having focus on data collection is suggested for integrating databases and comprehensive analysis.

    Download full text (pdf)
    fulltext
  • 9. Abu-Khader, M. M.
    et al.
    Shawaqfeh, A. T.
    Naddaf, Z.
    Maity, J. P.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Radon in the groundwater in the Amman-Zarqa Basin and related environments in Jordan2018In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 7, p. 73-81Article in journal (Refereed)
    Abstract [en]

    The occurrence of radon (222Rn) in environment (groundwater and indoor air) from geogenic sources is receiving an growing attention due to its adverse impact on human health worldwide including Jordan. Highlighting the current status of radon in Jordan, the present study of radon concentrations in ground waters in the Amman-Zarqa basin (AZB) was investigated. Groundwater samples were collected from fifteen wells located in three main areas of Ras Al-Ain, Al-Rsaifeh and Al-Hashemite. Radon concentration was measure using Liquid scintillation counting (LSC) Tri- Carb 3110 with discriminator and the highest values for radon concentration in water were observed in Al-Rsaifeh area and ranged from 4.52 up to 30.70 Bq/l with an average of 11.22 Bq/l, which were attributed to the decay of naturally distributed uranium in phosphate rock from Al-Rsaifeh mines. In Ras Al-Ain area, the radon concentration were noted ranged from 0.6 to 5.55 Bq/l with an average of 2.82 Bq/l, and also in Al-Hashemite area were ranged from 0.77 to 5.37 Bq/l with an average of 4.04 Bq/l. The overall average concentration of tested samples was 5.77 Bq/l and found within the acceptable international levels. Ground water samples of Ras Al-Ain area showed good quality as was tested of low salinity. It recorded the lowest average radon concentration of 2.82 Bq/l. Also, Radon indoor and building materials was reviewed. In conclusion, this study presented an urged need for developing national regulations and standards as well as awareness program concerning the radon status in Jordan.Elsevier B.V.

  • 10.
    Acheampong, Isaac
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Urban biodiversity; a global perspective.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A majority of the world’s cities are situated in or near areas of high biodiversity. Rise in global urban population resulting in rapid urban expansions (larger cities) is a threat to urban biodiversity, which has implications for the ecological health and general well being of humans. The study exploits consistent global land use data to compare 102 cities across the globe on a measure of urban biodiversity, within 15 km and 30 km from the approximate centres of the cities. Cities with high population and higher percentage of land use dedicated to artificial infrastructure recorded lower percentage size reserved for natural habitat, and vice versa. Further testing in regression analysis with birds and plants species as response variables shows a relation with urban extent and size of natural habitat which seeks to promote sustaining ecosystems services. Since urban biodiversity has implications for human ecological health, its indicators must be constantly measured and monitored, while adhering to best practices that conserve nature.

    Download full text (pdf)
    fulltext
  • 11.
    Ackebo, Jonas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Brandt, Anna-Clara
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Dobraja, Kristine
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Isaksson, Sarah
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Liebmann, Andrew
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Lindberg, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Lundgren, Monia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Song, Meng
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Svenfelt, Åsa
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Zachrisson, Maja
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    What is the potential to create a just social-ecological in Fisksätra/Saltsjöbaden?: Report from the Ecosystem support and Environmental Justice course (AG2803)2013Report (Other academic)
    Download full text (pdf)
    fulltext
  • 12. Adams, Sophie
    et al.
    Kuch, Declan
    Diamond, Lisa
    Fröhlich, Peter
    Henriksen, Ida-Marie
    Katzeff, Cecilia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Ryghaug, Marianne
    Yilmaz, Selin
    Social license to automate: A critical review of emerging approaches to electricity demand management2021In: Energy Research & Social Science, ISSN 2214-6296, E-ISSN 2214-6326, Vol. 80, no October, p. 102210-12, article id https://doi.org/10.1016/j.erss.20102210Article in journal (Refereed)
    Abstract [en]

     Electricity demand-side management (DSM) programs are becoming increasingly important to energy system managers in advanced industrialized countries, especially those with high renewable energy penetration. As energy user participation is paramount for their success but has proven to be difficult to obtain, we explore the usefulness of the ‘social license’ concept, originally developed in the mining sector, to refer to the process of creating acceptance in DSM programs aimed at managing or controlling household energy resources such EVs, batteries, and heating and cooling devices. We argue that analyzing the attainment or lack of ‘social license’ may be useful to energy policy-makers and researchers for understanding public concerns with not only supply-side energy resources, but also DSM. We do so by (1) drawing attention to potential frictions between demands for flexibility on the one hand and social practices and habits on the other; (2) attending to the ways that users’ engagement in DSM programs is influenced by their sense of control and agency, and their trust in program providers; and (3) exploring the ways that users may understand their stake in the energy system and may participate in programs as collectives rather than simply as individuals. We argue that a ‘social license to automate’ could not only describe a set of tools to manage participation in DSM projects, but rather assess the ways users effectively feel part of new energy systems designed to serve them. 

  • 13.
    Adediran, Gbotemi A.
    et al.
    Swedish Univ Agr Sci, Dept Soil & Environm, Box 7014, S-75007 Uppsala, Sweden..
    Tuyishime, J. R. Marius
    Swedish Univ Agr Sci, Dept Soil & Environm, Box 7014, S-75007 Uppsala, Sweden..
    Vantelon, Delphine
    Synchrotron SOLEIL, St Aubin BP 48, F-91192 Gif Sur Yvette, France..
    Klysubun, Wantana
    Synchrotron Light Res Inst, 111 Moo 6, Muang, Nakhon Ratchasi, Thailand..
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Swedish Univ Agr Sci, Dept Soil & Environm, Box 7014, S-75007 Uppsala, Sweden..
    Phosphorus in 2D: Spatially resolved P speciation in two Swedish forest soils as influenced by apatite weathering and podzolization2020In: Geoderma, ISSN 0016-7061, E-ISSN 1872-6259, Vol. 376, article id 114550Article in journal (Refereed)
    Abstract [en]

    The cycling and long-term supply of phosphorus (P) in soils are of global environmental and agricultural concern. To advance the knowledge, a detailed understanding of both the vertical and lateral variation of P chemical speciation and retention mechanism(s) is required, a knowledge that is limited in postglacial forest soils. We combined the use of synchrotron X-ray fluorescence microscopy with multi-elemental co-localisation analysis and P K-edge XANES spectroscopy to reveal critical chemical and structural soil properties. We established a two-dimensional (2D) imagery of P retention and speciation at a microscale spatial resolution in two forest soil profiles formed in glaciofluvial and wave-washed sand. The abundance and speciation of P in the upper 40 cm was found to be influenced by soil weathering and podzolization, leading to spatial variability in P speciation on the microscale (< 200 pm) with P existing predominantly as organic P and as PO4 adsorbed to allophane and ferrihydrite, according to XANES spectroscopy. These species were mostly retained at sharp edges and in pore spaces within Al and Si-bearing particles. Despite the relatively young age ( < 15,000 years) of the soils, our results show primary mineral apatite to have weathered from the surface horizons. In the C horizon however, a large fraction of the P was in the form of apatite, which appeared as widely dispersed ( > 600 pm) hot spots of inclusions in aluminosilicates or as discrete micro-sized apatite grains. The subsoil apatite represents a pool of P that trees can potentially acquire and thus add to the biogeochemically active P pool in temperate forest soils.

  • 14.
    Adem Esmail, Blal
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment. Ruhr University Bochum, Institute of Geography, Universitätsstr. 150, 44805 Bochum, Germany.
    Cortinovis, Chiara
    Suleiman, Lina
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Albert, Christian
    Geneletti, Davide
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Greening cities through urban planning: A literature review on the uptake of concepts and methods in Stockholm2022In: Urban Forestry & Urban Greening, ISSN 1618-8667, E-ISSN 1610-8167, p. 127584-Article in journal (Refereed)
    Abstract [en]

    Nature-based solutions (NBS) represent the most recent of several "greening" concepts proposed to support spatial planning and decision-making towards sustainable metropolitan regions. Despite similarities, the concepts stem from different disciplines and policy arenas and reflect various models of people-nature relations. This paper aims to analyze the uptake of greening concepts in scientific planning literature focusing on (urban) nature and landscape in the metropolitan region of Stockholm, Sweden, over the last three decades. It investigates what changes this evolution has brought in terms of the topics adopted, methods applied, and types of planning support put into practice. We identified 574 articles that reflect substantial research on greening concepts in the Swedish planning context. The articles demonstrate an initial prevalence of biodiversity with later increases of interest in ecosystem services and NBS. A detailed analysis of the studies focusing on Stockholm revealed Population growth/densification, Green space management and Biodiversity conservation as the most commonly addressed societal challenges. The most frequently mentioned type of green and blue element is Parks and (semi-)natural urban green areas, including urban forests. Methods applied were mostly quantitative, while mixes with qualitative approaches were only apparent in ecosystem services articles. Half of the studies involved practitioners or decision-makers, but only four seemed related to real-life planning processes. Taken together, the influence of scientific literature on the uptake of greening concepts in spatial planning seems to have been limited. Future mainstreaming of greening concepts in Stockholm and beyond could benefit from available data, methods and experiences, but will require more active translation and boundary management. Further research into science-policy-planning interfaces at city scale is thus imperative to advance more sustainable pathways for people and nature in metropolitan regions.

  • 15.
    Agarwal, Tushar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    The Ganges drainage basin: Hydrological transitions due to anthropogenic water use.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Hydrological changes in catchments world over have affected regional climate and pose serious challenge to future water resource management. The Ganges drainage basin (GDB) is one such region which has undergone rapid transformation in land and water use, more specifically in the latter half of 20th century. GDB has a population of more than half a billion people and is spread across India, China (Tibet), Nepal and Bangladesh. Further, hydrological investigations accounting land and water use changes in GDB are rare. This study is an attempt to resolve hydrological changes in the Ganges basin using the fundamental water balance, focusing particularly on water use changes through irrigation. Between the period 1951-1959 and 1991- 2000, precipitation (P) in the Ganges basin has reduced by 11.25 % while evapotranspiration (ET) has only reduced by 3.61 %. In addition, the ET/P has increased from 0.483 to 0.525 during the same period suggesting a larger partitioning of P towards ET. This suggests greater utilization of P to release water vapor in the atmosphere and thus causing a reduced water flow downstream. With water availability at the fulcrum of future concern for regional and national water security, these findings should encourage policy makers to account for hydrological changes in the GDB in planning sustainable water use.

    Download full text (pdf)
    fulltext
  • 16. Agathokleous, E.
    et al.
    Barceló, D.
    Aschner, M.
    Azevedo, R. A.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Costantini, D.
    Cutler, G. C.
    De Marco, A.
    Docea, A. O.
    Dórea, J. G.
    Duke, S. O.
    Efferth, T.
    Fatta-Kassinos, D.
    Fotopoulos, V.
    Ginebreda, A.
    Guedes, R. N. C.
    Hayes, A. W.
    Iavicoli, I.
    Kalantzi, O. -I
    Koike, T.
    Kouretas, D.
    Kumar, M.
    Manautou, J. E.
    Moore, M. N.
    Paoletti, E.
    Peñuelas, J.
    Picó, Y.
    Reiter, R. J.
    Rezaee, R.
    Rinklebe, J.
    Rocha-Santos, T.
    Sicard, P.
    Sonne, C.
    Teaf, C.
    Tsatsakis, A.
    Vardavas, A. I.
    Wang, W.
    Zeng, E. Y.
    Calabrese, E. J.
    Rethinking Subthreshold Effects in Regulatory Chemical Risk Assessments2022In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 56, no 16, p. 11095-11099Article in journal (Refereed)
  • 17.
    Agewall, John
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Wallgren, Kim
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Mikroplastutsläpp från däckslitage: Ett rullande utsläpp2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The number of cars has been on a steady increase in Sweden and in mars 2019 there were almost 4,9 million cars in active use. Nowadays most of the attention is focused on pollution through carbon dioxide and the wear of roads. However, a problem that often goes unrecognized is the tear of car tyres and the release of microplastics into the environment. In order to quantify the amount of microplastics released into the environment, the Swedish government has instructed The Swedish National Road and Transport Research Institute (VTI) to carry through with this. The aim of this report is to, with the help of VTI, try to quantify the amount of microplastics released from private car traffic and examine the main types of tyre wear. This report consists of two parts, one study of what microplastics is and how tyre wear arises. The second part consists of measuring, where used tyres have had their weight and tread measured. The profile of the tear, DOT number, production date, model, dimensions and type of tyre is additional data that was collected. Through the use of data provided by the tyre companies and the collected data, the total loss of weight and volume together with a yearly weight and volume loss could be calculated. Through analysis of the tyre profiles and their tread depths the most occurring type of wear patterns was determined, which were central, even and side wear. The estimated yearly amount of microplastics released in Sweden was between 8 300 and 16 700 tonnes. 

    Download full text (pdf)
    fulltext
  • 18.
    Agewall, John
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Wallgren, Kim
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Rening av lösta metaller i vägdagvatten: Fullskaleförsök vintertid med reaktivt filtermaterial2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The growing infrastructure creates more impermeable surfaces, causing an increase in stormwater that brings contaminants from surfaces such as roofs and roads, spreading these in the environment. There are a number of different stormwater treatment methods but many lack the ability to remove metal ions. One promising method is the use of reactive filter materials. However, there is a limited amount of research conducted on how these reactive filter systems perform in natural conditions, especially in nordic environments with cold winters, de-icing salt application and usage of studded tyres. This study aims at in- vestigating how de-icing salt (NaCl), pH, temperature, clogging and water flow affect the treatment efficiency of the reactive filter material Filtralite® P in a real-life application. The catchment area that contributed water to the studied system had a total area of 17,600 m2, including parts of Essingeleden, one of the most trafficked roads in Sweden with an annual average daily traffic load of 140,000 vehicles.

    The studied system consisted of a stormwater pond fed with water from the catchment area. The pond connected to a measuring well which in turn was connected to a pumping well. From there, water was pumped upwards through two parallel wells (Filter 1 and Filter 2) containing Filtralite P and was then discharged into lake Ma ̈laren. Filter 1 was subjected to a higher hydraulic load compared to Filter 2, resulting i a residence time of four hours in Filter 1 and 9 - 24 hours in Filter 2. Water samples were collected in the measuring well and above the filter media in both reactive filter wells. This allowed for examination of the metal concentrations before and after the reactive filters. Measurements of pH, temperature, conductivity and turbidity were conducted in the measuring well and in both filter wells. In addition, measurements of head loss and water flow were also taken in the filter wells. The samples and measurements of this study were taken between 28/01-2021 and 16/04- 2021. Before that, the reactive filter material had been in use from June to December of 2020.

    The turbidity in the measuring well varied between 2 and 50 FNU. A decrease in turbidity was observed after the reactive filter media, with an average of 3.3 FNU in Filter 1 and 0.9 FNU in Filter 2. The amount of suspended solids in the water was estimated to not exceed 16 mg L−1 and in total, approximately 1.4 kg of suspended solids was removed in Filter 1 and 0.3 kg in Filter 2. The head loss through Filter 2 was highly correlated with the hydraulic load due to the drastic variations in flow. The head loss in Filter 1 was observed to increase slightly over time, indicating that clogging might start to take place. However, clogging of the filter media did not seem to be an issue for the system, a theory strengthened by the low turbidity and low increase in head loss. The temperature in the measuring well varied between 0 and 6 °C and in the filter wells between 1.1 and 7.4 °C. The low temperature might have negatively affected the efficiency of the reactive filter.

    An increase in pH was observed after the water passed through the reactive filters, with Filter 1 raising the pH to around 9 and Filter 2 to around 10 in the beginning of the testing period. This increase in pH would diminish over the period in Filter 1 to approximately 8, while Filter 2 maintained a stable pH increase. The conductivity increased over the measuring period and reached a peak in February to then decrease during March, most likely caused by increased and decreased use of de-icing salts. Chloride concentrations in the incoming stormwater varied between 119 - 4 990 mg L−1.

    The treated water after the reactive filters exhibited a reduced concentration of filtered copper and zink. Meanwhile, the concentrations of calcium, iron, manganese and nickel increased in Filter 1, but decreased in Filter 2. Filtered chromium decreased in Filter 1 but no statistically significant reduction was observed in Filter 2. However, the reduction of chromium might have been more efficient, due to a majority of measurements showing concentrations below the detection limit after the reactive fitlers. There was an increased concentration of filtered molybdenum and magnesium after the reactive filters. The metals cadmium, lead and mercury were merely present in very low concentrations or below the de- tection limit of laboratory instruments. Futher investigations of these metals were therefore not conducted.

    In general, Filter 2 achieved a higher metal treatment efficiency compared to Filter 1. This is believed to be caused by the higher hydraulic load in Filter 1. This caused a pH reduction in the filter material which in turn led to a reduced adsorption efficiency and possibly enhanced the competition effect between the dissolved metals and the sodium ions from the de-icing salts. A correlation was found between chloride and calcium, manganese and iron in Filter 1. In Filter 2 there was a correlation between chloride and calcium, unfiltered magnesium and zink. The chloride concentrations are related to the de-icing salts and it is believed that the salts could have an impact on the efficiency of metal reduction in Filtralite P. At chloride concentrations of around 2 500 mg L−1 the concentrations of zink, magnesium, iron, copper and calcium seemed to increase in the effluent water, meaning that there might also be a threshold value, which if passed, leads to increased metal mobilization.

    The higher performance of Filter 2 might also be due to longer residence times. This increa- sed residence time might have allowed for a greater reduction of metals due to an increased contact time. It is important to note that more bed volumes had passed Filter 1 compared to Filter 2, with a total of 321 bed volumes through Filter 1 and 53 bed volumes through Filter 2 during the period of this study. However, if previous bed volumes are also taken into account, a total of 1,157 bed volumes have passed Filter 1 and 559 have passed Filter 2. This could also have caused the reduced efficiency observed in Filter 1 compared to Filter 2. 

    Download full text (pdf)
    fulltext
  • 19.
    Aggarwal, Rahul
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Strategic Assessment of Drinking Water Production Systems Environmental impacts from a Life cycle perspective: A case study of Norrvatten future drinking water production alternatives2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Climate change is a global challenge that requires proactive action from municipalities, companies, and other organizations to prioritize sustainability in their daily operations. In the past few decades, life cycle assessment (LCA) approach has been successfully applied for environmental assessments in the drinking water sector. In this study, this approach has been used to present a comparative evaluation of the potential environmental impacts associated with nine different process alternatives for future drinking water production at Norrvatten. This study is a pioneering one that explores the potential of LCA as a decision support tool to prioritize and optimize environmental impacts during the operational phase in Swedish drinking water production.

    The nine alternatives are designed for the year 2050 to meet the average daily demand of 208 MLD for the 14 municipalities in the northern Stockholm region that Norrvatten supplies with drinking water. Out of the nine alternatives, the alternative based on direct filtration of raw water on nanofiltration membranes came out as the most environmentally friendly solution due to the use of renewable electricity from hydro and wind power. The results indicate that the potential environmental impacts are dominated by the use of chemicals in all alternatives, which in turn depends on the energy sources used for chemical production that are mostly dominated by fossil-based non-renewable sources. The impacts due to transportation and energy consumption are relatively less in Swedish drinking water production. Moreover, filtration through granulated activated carbon (GAC) is the most environmentally damaging treatment step, but regeneration of saturated GAC induces positive impacts in all alternatives. Among environmental impact categories, categories related to fine particulate matter formation; global warming, human carcinogenic toxicity, and human non-carcinogenic toxicity are the most significant in all alternatives.

    Several of the treatment technologies included in the nine alternatives, such as Nanofiltration, have only been tested on a pilot scale and have not been used for drinking water production at Norrvatten. So this study should be followed up and supplemented with better representative inventory data relevant to the Swedish context in order to contribute more effectively in making the future Swedish drinking water production more sustainable and environmentally friendly. Also, this study is based on the most recently available data that may not be valid in 2050 and the latest trends to substitute non-renewable energy sources with renewable sources may reduce the impacts due to chemical production and transportation in the future. Moreover, this LCA study does not include any aspects of water quality and treatment costs. Hence, while comparing different alternatives, the quality of the treated water and its production cost must also be taken into account.

    Download full text (pdf)
    fulltext
  • 20.
    Agnarsson, Madelene
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Larsson, Marie
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Hjälpmedel vid beräkning av grundvattensänkning för att underlätta prissättning i anbudsfas.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Grundvattensänkningar är något som ofta behöver utföras innan konstruktion av anläggningar i jord. Att sätta pris på en grundvattensänkning är inte särskilt lätt när information eller kompetenser saknas som krävs för att göra en rimlig bedömning. Veidekke Entreprenad Anläggning Öst är ett anläggningsföretag som oftast jobbar i generalentreprenadsform. Vid en generalentreprenad så är projekteringen redan gjord och pris ska sättas på de olika posterna som behöver utföras.

    Denna rapport presenterar en förenklad process för kalkylberäkningar i anbudsfas. Därför har en mall har tagits fram åt Veidekke. Denna mall består av fyra representativa typjordar och ekvationer som gör den användarvänlig. För att kontrollera mallens duglighet så testades den sedan på tre projekt som Veidekke utfört grundvattensänkningar på. Mallens beräknade resultat kunde då jämföras med observerade resultat. Det visade sig att mallen ger en god approximation på hur grundvattensänkningen kan se ut och en fingervisning på hur lång tid det kan ta innan stationär grundvattensänkning uppkommer.

    Download full text (pdf)
    fulltext
  • 21.
    Aguilar, Mónica García
    et al.
    Swedish University of Agricultural Sciences, Department of Urban and Rural Development.
    Jaramillo, Juan Felipe
    Universidad El Bosque.
    Ddiba, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management. Stockholm Environment Institute.
    Páez, Diana Carolina
    Universidad El Bosque.
    Rueda, Hector
    Universidad El Bosque.
    Andersson, Kim
    Stockholm Environment Institute.
    Dickin, Sarah
    Stockholm Environment Institute.
    Governance challenges and opportunities for implementing resource recovery from organic waste streams in urban areas of Latin America: insights from Chía, Colombia2022In: Sustainable Production and Consumption, ISSN 2352-5509, Vol. 30, p. 53-63Article in journal (Refereed)
    Abstract [en]

    Across the globe, there is increasing interest in implementing circular approaches to urban sanitation and waste management to mitigate environmental challenges and promote sustainable business opportunities. In Latin America where 80% of the population live in urban areas, there is limited investigation into the enabling factors and governance barriers that are critical to implementing circular economy strategies in urban areas. This paper aims at assessing the governance capacity to implement resource recovery from organic waste streams in the municipality of Chía, Colombia, through applying the Governance Capacity Framework in a participatory process with local stakeholders. The findings highlight the importance of local initiatives for resource recovery that allow experimentation, raise awareness and foster collaboration, as well as mechanisms available for public participation in decision-making processes as enabling factors. Meanwhile, the inadequate monitoring and assessment of environmental strategies and policies, inadequate sharing of information among stakeholders and the relative low awareness of potential benefits of recovering resources from organic waste streams, especially among public sector actors, emerge as key barriers. Beyond Chía, the results provide insights on crucial factors for ensuring sufficient governance capacity in other urban areas in low- and middle-income countries which are considering circular approaches to urban sanitation and waste management. The findings also provide an empirical basis to advance the understanding of the governance conditions necessary for implementing resource recovery from organic waste streams, upon which further applications of the governance capacity framework along with participatory aspects in other similar urban contexts could build.

    Download full text (pdf)
    fulltext
    Download (pdf)
    Supplementary Information
  • 22.
    Ahlberg, Fanny
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Ökad avbördningskapacitet hos befintliga dammar i Sverige: En fallstudie över damm i mellersta Norrland2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Intresset för klimatförändringar, och problem som kommer med dessa, har ökat de senaste årtiondena. En effekt som dessa drar med sig är att de beräknade extremflödena förväntas öka vilket påverkar säkerheten hos befintliga dammar. Flödesdimensioneringsriktlinjerna, vilket kortfattat är riktlinjer för att bestämma dimensionerande flödet i Sverige, reviderades 2015 till att också ta hänsyn till ett föränderligt klimat. Detta leder till krav på befintliga dammar att öka sin avbördningskapacitet samtidigt som intresset för mindre traditionella utskovsanordningar ökar för att säkerställa tillförlitligheten hos utskoven. Denna studie är en fallstudie över en dammanläggning i mellersta Norrland som på grund av en förhöjd klassificering måste öka sin avbördningskapacitet. Syftet med studien är att föreslå åtgärder på dammen som leder till att avbördningskapaciteten blir i linje med flödesdimensioneringsriktlinjerna och att denna rapport ska kunna användas som stöd och underlag när andra dammar i Sverige har motsvarande utmaning. Åtgärderna togs fram genom att först identifiera möjliga utskovsanordningar med avseende på dammens konstruktions- och geologiska förutsättningar samt driftaspekter i ett svenskt klimat. De fördelaktiga utskovsanordningarna anpassades för den aktuella dammanläggningen och avbördningsberäkningar för möjlig design av utskoven utfördes. De åtgärder som kunde avbörda flöden enligt flödesdimensioneringsriktlinjerna utvärderades med avseende på stabilitet i de fall som ansetts möjliga. Efter en diskussion kring olika för-och nackdelar med de olika åtgärderna, med avseende på bland annat ekonomi, föreslogs möjliga lösningar. De utskovsanordningar som enligt resultatet var fördelaktiga att implementera för dammanläggningen var överfallsutskov, både kontrollerat och okontrollerat, och labyrintutskov. Avbördnings-och stabilitetsberäkningarna samt diskussionen kring för och nackdelar kring åtgärderna ledde fram till att tre åtgärder kunde föreslås. Alla tre alternativen innefattade ytvattenutskov, även kallade överfallsutskov med lucka, och var antingen att bygga om befintliga utskov, bygga till ett ytterligare utskov eller en kombination av de två. Labyrintutskovet visade sig ha ganska hög kapacitet, men uppfyllde inte kravet om klass II-flöde vid dämningsgräns. En generell slutsats som kunde dras av studien var att det finns ganska många olika alternativ på utskovsanordningar, men problem och osäkerheter med igenfrysning, drivgods och kavitation måste kunna hanteras i Svenskt klimat. Okontrollerade utskov kan vara ett alternativ, och då främst labyrintutskov, men det förutsätter att dammen med befintlig avbördningskapacitet kan avbörda klass II-flöde.

    Download full text (pdf)
    fulltext
  • 23.
    Ahlberg, Fanny
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Ivansen, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Analys över variationer i vattenförbrukning och dess påverkandefaktorer: En fallstudie över områden i Borås2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The steady supply of fresh water is, and has always been, one of the most important functions in human societies. Different users have been able to take advantage of this resource in different extents and for different purposes. The major areas for water usage are drinking water, water supply for industrial purposes and the usage in agricultural sector.

    By dimensioning the supply- and sewer systems accordingly to the demand of the users a more sustainable and optimal system can be achieved. A proper dimensioning has six general factors it should to take in consideration. These are the size of the population, water consumption in residents, general water consumption in schools and offices, water consumption in industry, leakage and different water losses. With a background of these factors this reports main focus and purpose is analysing the variation in water consumption for different consumers (such as residential houses or apartment blocks) in different time intervals (in this report during days and years) and in respect to different factors. The factors that has been chosen to be examined is how water consumption depends on mean age of the consumers and the outdoor temperature. To complete this study water consumption data of different areas in Borås has been provided from the Swedish consultant firm Tyréns. Before analysing the data another study was made by Victor Eliasson, which included the revealing of different faults in the provided data. As a result of this study the most reliable data was chosen to further analysis with respect to the chosen aspects. During the project the calculation- and modelling program Matlab was used alongside the chart program excel. These two programs combined made it possible to handle large amounts of data and present it in different graphs and models. Conclusions could later be made by analyses and different statistical methods. The result from the comparison between areas with different mean ages of the residents showed that the area with high mean age (80 years) hade a higher water consumption than the other areas. The variation in water consumption differed as well between the area with the high mean age compared to the other areas. A regression- and correlation analysis between water consumption and temperature was performed to see if water consumption is depending on the outdoor temperature. The function of a regression analysis is to describe the relation between different parameters with a mathematic model (in this study a linear model). A correlation analysis is then performed to tell how well the mathematic model describes the relation. A conclusion could be made that the water consumption tends to increase with increasing temperature during parts of the year, since a correlation could be found during mars to September. The strongest correlation was in general during May and July for all the areas. No conclusion of how the variation i water consumption depends on different consumers could be made for the analysis during a day and a year. In contrast to the parameters that had a correlation with water consumption there was no visible connection between water consumption over a year or day depending on different users. 

    Download full text (pdf)
    fulltext
  • 24.
    Ahlbom, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Åtgärdsförslag till ett översvämningsdrabbat område i Tranås2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Global warming is causing changes in precipitation patterns world over. Many places can expect to face longer periods of drought, while others may be facing periods with increased amounts of precipitation. Europe has created a Flooding Directive in order to prevent consequences of flooding. In Sweden a work of mapping areas with risk of flooding has been a first step to fulfill the Directive. Secondly, all areas that are affected shall create risk plans where their different strategies and work plans are being presented. WSP have mapped areas in Tranås in Jönköping, Sweden, in order to find out which areas could be the most vulnerable to flooding after a heavy downpour. The mapping is being performed with the software Mike+ that is developed by DHI, and the rain event that has been used is a 100-year downpour with an added climate factor. In this report one of the mapped areas in Tranås, has been selected in order to present proposed measures. The measures consist of dry ponds and ditches and are being designed with different dimensions. Simulations have been performed in Mike+ in order to study the different measure‘s effects after a 100-year storm event. The results show that the implemented dry pond needs to be rather big to show good effect. The best effect was shown with the dry pond of 4970 square meters and with an outlet line that had a dimension of 300 mm, which was 80 mm larger than the original. The result showed that about 90 percent of the parking lot could be used after the implementation. Furthermore, the results showed that with a pond measuring 4142 cubic meters, about 50 percent of the parking lot could be used. Overall, dry ponds showed potential of working as a measure against flooding in the area. Urban areas that are densely built could benefit from having dry ponds and ditches implemented. Their flexibility is valuable since they can be used for different purposes during dry periods, which can be useful in areas that are densely built.

    Download full text (pdf)
    fulltext
  • 25.
    Ahlfors, Charlotta
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Bergkrantz, Malin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Energieffektivisering av en bandybana: Analys av kompressorkylteknik och fjärrvärmedriven absorptionskylteknik2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, the energy consumption in the world is increasing and Sweden is not an exception. Therefore, the continued work towards a sustainable development is essential in order for future generations to have the same opportunities as the people today. An important step towards this goal is to improve the energy efficiency until the next generations technology has been developed. As a result of this the energy resources of the earth could be saved which would lead to cost savings, due to the fact that operating costs would decrease with reduced energy consumption. A reduced electrical power generation would lead to reduced emissions of substances that affect the environment as well. The municipality of Västervik has worked towards a sustainable development for a long time; therefore energy efficiency in the public sector has been implemented.

    An analysis is done, based on a literature study and calculations, in purpose to decide if a change of the cooling system used for the outdoor ice rink in Gamleby would lead to reduced energy consumption and cost savings. The two different machines analysed are the existing compressor cooling machine and an alternative absorption cooling machine in combination with district heat from a local source. If excess of distinct heat could be used as heat source it would be positive for the environment and for sustainable development.

    Through calculations of the cooling demand, the sustainable economy and the CO2-emissions the following conclusions have been made. Since the coefficient of cooling performance is lower for the absorption cooling machine a switch of cooling system would result in a higher demand of energy (heat and power). Due to the different CO2-emission coefficients of the two energy sources a switch would lead to increase of CO2-emissions as well as reduce the efficiency of the resources of the earth.

    The investment cost for an absorption cooling machine is double the investment cost for a commercial compressor cooling machine. Therefore, calculations have shown that it would take 18 years until a change of the cooling system can be seen as cost-effective. This calculation is based on the most optimal conditions such as free district heating and a high value on the coefficient of performance. As well if the district heat would cost, a change would never be cost-effective. The life span of a cooling machine is approximately 25 years and due to the fact that the calculations for the optimal case are based on assumptions that are not confirmed, for instance the energy from the district heat would be free of charge, the authors of this study cannot recommend the change of cooling method for the ice rink seen through an economical perspective. To sum up, the conclusion is that a switch to absorption cooling will not result in an improvement in terms of energy efficiency, cost benefits or emission reduction. Instead, an analysis of the existing system should be made in order to identify efficiency improvement opportunities in areas such as optimization of the control system and reducing the cooling demand of the bandy ice by reducing heat transfer from the environment. 

    Download full text (pdf)
    fulltext
  • 26.
    Ahlgren, Ellen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Compilation of Life Cycle Assessments of Cultivated Brown Seaweed: A recalculation of Life Cycle Inventories2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Seaweed production systems are necessary to fill a product demand in multiple sectors whilst contributing to the bioeconomy. The multiple seaweed qualities drive the research for sustainable seaweed production worldwide. The main studies of seaweed production consist of life cycle assessments, where cradle-to-gate analyses have been calculated. However, these assessments have had incomparable results because of the various methods used. Therefore, this thesis utilized the life cycle inventories of six previously made life cycle assessments of brown seaweed and recalculated these concerning three key environmental impact categories – Global warming potential, Freshwater Eutrophication, and Marine Eutrophication. This was done by collecting and recalculating the six different inventories to the same functional unit and then assessing the environmental impacts of the recalculated inventories. The results showed that the life cycle impact assessments of brown seaweed production varied, yet the most impacts could be seen during the cultivation stage of the life cycle, mainly due to the plastics used within the system. The variations in the results are a consequence of the various data resources used, the design and location of the production systems, and the goal and scope of the reports. This thesis also demonstrated that a replication of life cycle assessments includes several obstacles, questioning the scientific method of LCA, for example, lack of transparency and deficiency in reporting methods and data. 

    Download full text (pdf)
    fulltext
  • 27.
    Ahlgren, Ellen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Nordborg, Mikael
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Rainwater harvesting på Storsudret: Potential för implementering på södra Gotland2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many places around the world, including parts of Sweden, suffers from seasonal lack of water. This can be dealt with by storing precipitation in times when the availability is good. One example of such an area is Storsudret on the southernmost part of Gotland. The focus of this report was to analyze the potential of implementing rainwater harvesting methods in Storsudret. The project was initiated with a literature study of existing methods for rainwater harvesting and an evaluation was made whether or not they were suited for the area and data from SMHI and Lantmäteriet was analyzed and compiled in Excel and ArcMap to assess the potential for rainwater harvesting. What this report shows, according to the calculations and map analysis made, is that there is potential in applying rainwater harvesting methods to the area Storsudret, Gotland. The main factors include the meteorological conditions, more specifically, the general spread of precipitation over a year and to the total amount of precipitation in a year. This together with the other factors is needed to evaluate if rainwater harvesting is a viable option for water supply at Storsudret. The other factors are mainly the size of rooftops in relation to the amount of people living in this area. Depending on each households’ own conditions, mainly water usage, rooftop size and storage capacity, the extent of which rainwater harvesting can be applied, varies. These types of solutions can not only help with a less stress on the groundwater storage, but it can also help those households that doesn’t have acceptable groundwater quality or cannot be connected to the municipal water systems. What this comes to show is that rainwater harvesting is an engineering technique that could help solve problems concerning shortage of water, not only at Storsudret, but also in other places in Sweden or in the world.

    Download full text (pdf)
    fulltext
  • 28.
    Ahlgren, Serina
    et al.
    SLU.
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Ekman, Anna
    Lund University.
    Karlsson, H
    SLU.
    Berlin, Johanna
    SP.
    Börjesson, Pål
    Lund University.
    Ekvall, Tomas
    IVL.
    Finnveden, Göran
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Janssen, Matty
    Chalmers.
    Strid, Ingrid
    SLU.
    LCA of biorefinieries -identification of key issues and methodological recommendations2013Report (Other academic)
    Download full text (pdf)
    fulltext
  • 29.
    Ahlgren, Serina
    et al.
    Swedish University of Agricultural Sciences.
    Björklund, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Ekman, Anna
    SP Technical Research Institute of Sweden.
    Karlsson, Hanna
    Swedish University of Agricultural Sciences.
    Berlin, Johanna
    SP Technical Research Institute of Sweden.
    Börjesson, Pål
    Lund University.
    Ekvall, Tomas
    IVL Swedish Environmental Research Institute.
    Finnveden, Göran
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Janssen, Matty
    Chalmers University of Technology.
    Strid, Ingrid
    Swedish University of Agricultural Sciences.
    Review of methodological choices in LCA of biorefinery systems: key issues and recommendations2015In: Biofuels, Bioproducts and Biorefining, ISSN 1932-104X, E-ISSN 1932-1031, Vol. 9, no 5, p. 606-619Article in journal (Refereed)
    Abstract [en]

    The current trend in biomass conversion technologies is toward more efficient utilization of biomass feedstock in multiproduct biorefineries. Many life-cycle assessment (LCA) studies of biorefinery systems have been performed but differ in how they use the LCA methodology. Based on a review of existing LCA standards and guidelines, this paper provides recommendations on how to handle key methodological issues when performing LCA studies of biorefinery systems. Six key issues were identified: (i) goal definition, (ii) functional unit, (iii) allocation of biorefinery outputs, (iv) allocation of biomass feedstock, (v) land use, and (vi) biogenic carbon and timing of emissions. Many of the standards and guidelines reviewed here provide only general methodological recommendations. Some make more specific methodological recommendations, but these often differ between standards. In this paper we present some clarifications (e.g. examples of research questions and suitable functional units) and methodological recommendations (e.g. on allocation).

  • 30.
    Ahlkvist, Ossian
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Är avloppsreningsverk lämpliga mottagare av backspolvatten från simhallar?2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Swimming pools are used as leisure centers, for sports or as therapeutic rehabilitation, and in Stockholm municipality there are 15 municipal swimming facilities and very many private ones in the form of, for example, hotel pools. A relatively inattentive problem with these pools lies in the chemical reactions that take place in the water. Sodium Hypochlorite reacts in the pool with organic material to form Adsorbable Organic Halides (AOX) and Extractable Organic Halides (EOX). These get stuck in the filter at the plant locally and free chlorine can form additional AOX in the wastewater network. These compounds are harmful for humans and animals to ingest and sometimes even to come into direct contact with. These substances have been studied to bioaccumulate in living organisms and have caused problems such as impaired reproductive capacity and other cell damage. The substances have also been observed to accumulate in dunes in watercourses. These substances that are created then get stuck in the filtration systems that are located locally at the plants due to pressure differences in these. When this happens, the filters need to be backwashed and this generates concentrated contaminated water. 

    In the background, I have examined different kinds of disinfection methods in swimming pools, as well as different ways to treat wastewater of AOX and EOX in treatment plants. This was done to build a good background to the issue at hand of AOX and EOX. 

    In this bachelor's thesis, I have studied how many swimming facilities there are in the catchment area of the Käppalaverket, Bromma treatment plant, and Henriksdal treatment plant. With this information, I have found out how much water is generated by pools at these facilities and supplemented these figures using standard values obtained from managers and estimated from received values. 

    Download full text (pdf)
    fulltext
  • 31.
    Ahmad, A.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. KWR Water Cycle Research Institute, Nieuwegein, Netherlands; Department of Environmental Technology, Wageningen University and Research (WUR), Wageningen, Netherlands.
    van Mook, J.
    Schaaf, B.
    van der Wal, A.
    Arsenic removal to <1 µg l−1 by coprecipitation with in-situ generated Fe(III) precipitates with and without advanced pre-oxidation2018In: Environmental Arsenic in a ChangingWorld - 7th International Congress and Exhibition Arsenic in the Environment, 2018, CRC Press/Balkema , 2018, p. 591-592Conference paper (Refereed)
    Abstract [en]

    The aim of this study is to investigate removal of low As concentrations from groundwater at a Drinking Water Treatment Plant (DWTP) in The Netherlands in order to achieve &lt;1 µg L−1 As in produced drinking water. Two iron based emerging technologies, both relying on in-situ generated Fe(III) precipitates for As adsorption, were investigated. These include: 1) Advanced Oxidation-Coprecipitation-Filtration (AOCF) and 2) Coprecipitation prior to ultrafiltration (C-UF). We show that most of the As removal occurs in the top half of a Rapid Sand Filter (RSF) bed. In this part we also observe the conversion of As(III) into As(V). The mechanism of As(III) oxidation to As(V) in the RSF is still not understood, however we hypothesize that either the manganese oxides or the biological activity in the filter bed may be responsible for this conversion. In agreement with this observation, we also notice that drinking water only contains As(V) and that the levels of As(III) are negligible. The experiments have shown that both AOCF and C-UF are promising emerging technologies to reduce arsenic levels to below 1 µg L−1 which is the agreed target in The Netherlands between the Dutch water companies. 

  • 32.
    Ahmad, Arslan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Brabant Water NV, 5200 BC 's-Hertogenbosch, The Netherlands.
    Evaluation and optimization of advanced oxidation coagulation filtration (AOCF) to produce drinking water with less than 1 μg/L of arsenic2014Report (Other academic)
    Abstract [en]

    Arsenic is an extremely poisonous element. It has been reported to cause contamination of drinking water sources in many parts of the world. The current drinking water permissible limit for arsenic in the European Union is 10 μg/L. The World Health Organization has a general rule that no substance may have a higher lifetime risk of more than 1 in 100,000. However, several studies on toxicity of arsenic suggest that purely based on health effects the arsenic limit of 10 μg/L is not sufficient. The main goal of this research was to develop an efficient arsenic removal technology that could be able to produce drinking water with an arsenic concentration of less than 1 μg/L. For this purpose, an innovative three step technique, Advanced Oxidation - Coagulation - Filtration (AOCF), was investigated through bench-scale and pilot scale experiments in the Netherlands at the water treatment plant of Dorst. Firstly, prior to the investigations on AOCF, the existing arsenic removal at the water treatment plant was investigated. Secondly, through a series of bench-scale experiments, the optimum type of coagulant, its combination dose with the selected chemical oxidant and optimum process pH were determined. Eventually, the partially optimized technique from the bench-scale was implemented at the pilot scale physical model of water treatment plant Dorst where AOCF was evaluated for arsenic removal and its effect on the removal of other common undesirable groundwater constituents. The optimized AOCF technology consistently removed arsenic from groundwater to below 1 ug/L when implemented at pilot scale. The overall effluent quality also remained acceptable. The method is efficient with both types of filtration media tested in this research i.e., virgin sand and metal oxide coated sand, however virgin sand media showed slightly better arsenic removal efficiency.

    Download full text (pdf)
    TRITA-LWR Report 2014-1_AOCF
  • 33.
    Ahmad, Arslan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Evaluation of organic residues and their mixtures with Peepoos to produce fertilizer.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Peepoo, self-sanitising, biodegradable toilet is characterized by low carbon to nitrogen (C-N) ratio and low dry matter (DM) content. Principal nutrients (nitrogen (N), phosphorous (P) and potassium (K)) are also not in a balance as required by most crops. It was expected that the mixing of used Peepoos with other organic materials might balance its chemical characteristics. In this thesis, availability and suitability of common organic materials produced in Kenya has been investigated for mixing with used Peepoo bags to obtain a balanced fertilizer product from the crop nutrition aspect. Seven organic residues were selected from the list of 13 on the basis of their availability near the processing site in Nairobi. The selected residues were then chemically analyzed for their individual plant nutrient content. The analysis results were used subsequently to simulate the chemical composition of a wide range of Peepoo-Residue mixtures. The evaluation of the theoretical mixtures based on DM content, C-N ratio and NPK ratio showed that the majority of investigated mixtures had DM content below 60 %. Majority of the mixtures showed C-N ratio between 10-1:1. All the mixtures deviated from the common nutrient uptake ratio of crops (1:0.5:1.4). Composite mixtures with more than 2 ingredients resulted in a balanced fertilizer product. The study concludes and recommends that the composite mixtures with more than two ingredients should be considered for practical processing of Peepoos into a commercial fertilizer product.

    Download full text (pdf)
    fulltext
  • 34.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Arsenic in Drinking Water: Is 10 μg/L a Safe Limit?2019In: Current Pollution Reports, ISSN 2198-6592, Vol. 5, no 1Article in journal (Refereed)
  • 35.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Environmental arsenic in a changing world2019In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 8, p. 169-171Article in journal (Refereed)
  • 36.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. SIBELCO Ankerpoort NV, Op Bos 300, NL-6223 EP Maastricht, Netherlands.;Wageningen Univ & Res WUR, Dept Environm Technol, Droevendaalsesteeg 4, NL-6708 PB Wageningen, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Global Groundwater: Source, Scarcity, Security and Solutions2021In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 15, article id 100605Article, book review (Other academic)
  • 37.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability and Environmental Engineering. KWR Water Cycle Res Inst, Nieuwegein, Netherlands.;WUR, Dept Environm Technol, Wageningen, Netherlands..
    Cornelissen, Emile
    KWR Water Cycle Res Inst, Nieuwegein, Netherlands.;Nanyang Technol Univ, Nanyang Environm & Water Res Inst, Singapore Membrane Technol Ctr, Singapore, Singapore.;Univ Ghent, Particle & Interfacial Technol Grp, Ghent, Belgium..
    van de Wetering, Stephan
    Brabant Water NV Breda, Breda, Netherlands..
    van Dijk, Tim
    Brabant Water NV Breda, Breda, Netherlands..
    van Genuchten, Case
    Univ Utrecht, Fac Geosci, Dept Earth Sci Geochem, Utrecht, Netherlands..
    Bundschuh, Jochen
    Univ Southern Queensland, Int Ctr Appl Climate Sci, West St, Toowoomba, Qld, Australia.;Univ Southern Queensland, Deputy Vice Chancellors Off Res & Innovat, Toowoomba, Qld, Australia.;Univ Southern Queensland, Fac Hlth Engn & Sci, Toowoomba, Qld, Australia..
    van der Wal, Albert
    WUR, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV Rotterdam, Rotterdam, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Univ Southern Queensland, Int Ctr Appl Climate Sci, West St, Toowoomba, Qld, Australia..
    Arsenite removal in groundwater treatment plants by sequential Permanganate-Ferric treatment2018In: Journal of Water Process Engineering, E-ISSN 2214-7144, Vol. 26, p. 221-229Article in journal (Refereed)
    Abstract [en]

    The Dutch drinking water sector is actively investigating methods to reduce arsenic (As) to < 1 mu g/L in drinking water supply. We investigated (1) the effectiveness of sequential permanganate (MnO4-)-ferric (Fe(III)) dosing during aeration-rapid sand filtration to achieve < 1 mu g/L As (2) the influence of MnO4--Fe(III) dosing on preestablished removal patterns of As(III), Fe(II), Mn(II) and NH4+ in rapid sand filters and (3) the influence of MnO4--Fe(III) dosing on the settling and molecular-scale structural properties of the filter backwash solids. We report that MnO4--Fe(III) dosing is an effective technique to improve arsenite [As(III)] removal at groundwater treatment plants. At a typical aeration-rapid sand filtration facility in the Netherlands effluent As concentrations of < 1 mu g/L were achieved with 1.2 mg/L MnO4--and 1.8 mg/L Fe(III). The optimized combination of MnO4-and Fe(III) doses did not affect the removal efficiency of Fe(II), Mn(II) and NH4+ in rapid sand filters, however, the removal patterns of Fe(II) and Mn(II) in rapid sand filter were altered, as well as the settling behaviour of backwash solids. The characterization of backwash solids by Fe K-edge X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) showed that the changed settling velocity of backwash solids with MnO4-Fe(III) in place was not due to changes in the molecular-scale structure of Fe-precipitates that constitute the major portion of the backwash solids.

  • 38.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands.;Wageningen Univ & Res WUR, Dept Environm Technol, Droevendaalsesteeg 4, NL-6708 PB Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Heijnen, Leo
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    de Waal, Luuk
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    Battaglia-Brunet, Fabienne
    French Geol Survey BRGM, 3 Ave Claude Guillemin,BP 36009, F-45060 Orleans 02, France..
    Oorthuizen, Wim
    Dunea Duin & Water NV, Pl Verenigde Naties 11-15, NL-2719 EG Zoetermeer, Netherlands..
    Pieterse, Brent
    Dunea Duin & Water NV, Pl Verenigde Naties 11-15, NL-2719 EG Zoetermeer, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    van der Wal, Albert
    Wageningen Univ & Res WUR, Dept Environm Technol, Droevendaalsesteeg 4, NL-6708 PB Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Mobility and redox transformation of arsenic during treatment of artificially recharged groundwater for drinking water production2020In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 178, article id 115826Article in journal (Refereed)
    Abstract [en]

    In this study we investigate opportunities for reducing arsenic (As) to low levels, below 1 mu g/L in produced drinking water from artificially infiltrated groundwater. We observe that rapid sand filtration is the most important treatment step for the oxidation and removal of As at water treatment plants which use artificially recharged groundwater as source. Removal of As is mainly due to As co-precipitation with Fe(III)(oxyhydr)oxides, which shows higher efficiency in rapid sand filter beds compared to aeration and supernatant storage. This is due to an accelerated oxidation of As(III) to As(V) in the filter bed which may be caused by the manganese oxides and/or As(III) oxidizing bacteria, as both are found in the coating of rapid sand filter media grains by chemical analysis and taxonomic profiling of the bacterial communities. Arsenic removal does not take place in treatment steps such as granular activated carbon filtration, ultrafiltration or slow sand filtration, due to a lack of hydrolyzing iron in their influent and a lack of adsorption affinity between As and the filtration surfaces. Further, we found that As reduction to below 1 mu g/L can be effectively achieved at water treatment plants either by treating the influent of rapid sand filters by dosing potassium permanganate in combination with ferric chloride or by treating the effluent of rapid sand filters with ferric chloride dosing only. Finally, we observe that reducing the pH is an effective measure for increasing As co-precipitation with Fe(III)(oxyhydr)oxides, but only when the oxidized arsenic, As(V), is the predominant species in water.

  • 39.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands.;;Wageningen Univ & Res, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Rotterdam, Netherlands..
    Rutten, Sam
    Wageningen Univ & Res, Dept Environm Technol, Wageningen, Netherlands..
    de Waal, Luuk
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    Vollaard, Peter
    Evides Water Co NV, Rotterdam, Netherlands..
    van Genuchten, Case
    Geol Survey Denmark & Greenland GEUS, Copenhagen, Denmark.;Univ Utrecht, Fac Geosci, Dept Earth Sci Geochem, Utrecht, Netherlands..
    Bruning, Harry
    Evides Water Co NV, Rotterdam, Netherlands..
    Cornelissen, Emile
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    van der Wal, Albert
    Wageningen Univ & Res, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Rotterdam, Netherlands..
    Mechanisms of arsenate removal and membrane fouling in ferric based coprecipitation-low pressure membrane filtration systems2020In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 241, article id 116644Article in journal (Refereed)
    Abstract [en]

    Ferric based coprecipitation-low pressure membrane filtration is a promising arsenic (As) removal method, however, membrane fouling mechanisms are not fully understood. In this study we investigated the effect of feed water composition and membrane pore size on arsenate [As(V)] removal and membrane fouling. We observed that As removal efficiency was independent of the membrane pore size because the size of the Fe(III) particles was larger than the pore size of the membranes, attributed to a high calcium concentration in the feed water. Arsenic coprecipitation with Fe(III) (oxyhydr)oxides rapidly reached equilibrium before membrane filtration, within 1 min. Therefore, As removal efficiency was not improved by increasing residence time before membrane filtration. The removal of As(V) was strongly dependent on feed water composition. A higher Fe(III) dose was required to reduce As(V) to sub-mu g/L levels for feed water containing higher concentration of oxyanions such as phosphate and silicate, and lower concentration of cations such as calcium. Cake-layer formation was observed to be the predominant membrane fouling mechanism.

  • 40.
    Ahmad, Arslan
    et al.
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands.;KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn, KTH Int Groundwater Arsen Res Grp, Stockholm, Sweden.;WUR, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Rutten, Sam
    WUR, Dept Environm Technol, Wageningen, Netherlands..
    Eikelboom, Martijn
    WUR, Dept Environm Technol, Wageningen, Netherlands..
    de Waal, Luuk
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    Bruning, Harry
    WUR, Dept Environm Technol, Wageningen, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    van der Wal, Albert
    WUR, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Impact of phosphate, silicate and natural organic matter on the size of Fe(III) precipitates and arsenate co-precipitation efficiency in calcium containing water2020In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 235, article id 116117Article in journal (Refereed)
    Abstract [en]

    Removal of arsenic (As) from water by co-precipitation with Fe(III) (oxyhydr)oxides is a widely used technique in water treatment. Nevertheless, As removal efficiency appears to be sensitive to the composition of the water matrix. The aim of this study was to gain a deeper understanding of the independent and combined effects of silicate (Si), phosphate (P), natural organic matter (NOM) and calcium (Ca) on arsenate [As(V)] co-precipitation efficiency and the size of Fe(III) precipitates. We found that, in complex solutions, containing multiple solutes and high levels of Ca, (variations in) Si and P concentrations reduce As(V) removal to some extent, mainly due to a decreased adsorption of As(V) onto Fe(III) precipitates. On the other hand, NOM concentrations reduced As(V) removal to a much greater extent, due to possible formation of mobile Fe(III)-NOM complexes that were difficult to remove by filtration. These findings have a great significance for predicting As(V) removal as a function of seasonal and process-related water quality changes at water treatment plants.

  • 41.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Hoofd Ingenieursbureau, Brabant Water N.V., 's-Hertogenbosch, Netherlands .
    Van De Wetering, S.
    Groenendijk, M.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Advanced Oxidation-Coagulation-Filtration (AOCF) - An innovative treatment technology for targeting drinking water with <1 μg/L of arsenic2014In: One Century of the Discovery of Arsenicosis in Latin America (1914-2014): As 2014 - Proceedings of the 5th International Congress on Arsenic in the Environment, CRC Press, 2014, p. 817-819Conference paper (Refereed)
    Abstract [en]

    Advanced Oxidation-Coagulation-Filtration (AOCF) has been investigated for producing drinking water with less than 1 μg L-1 of As through a series of bench scale and pilot scale experiments. At bench scale, the suitable coagulant, its combination dose with KMnO4 oxidant, the optimum process pH and kinetics of As removal were determined. The optimized AOCF technique was capable of consistently reducing the As concentration to below 1 μg L-1 when implemented at pilot scale and did not adversely affect the already existing removal processes of Fe, Mn and NH4 +. Dual media filter solved the filter run time reduction issue.

  • 42.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. KWR Water Cycle Res Inst, Nieuwegein, Netherlands.;WUR, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Rotterdam, Netherlands..
    van der Wal, Albert
    WUR, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Rotterdam, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Univ Southern Queensland, Int Ctr Appl Climate Sci, Toowoomba, Qld, Australia..
    van Genuchten, Case M.
    Geol Survey Denmark & Greenland GEUS, Geochem Dept, Copenhagen, Denmark.;Univ Utrecht, Fac Geosci, Dept Earth Sci Geochem, Utrecht, Netherlands..
    Characteristics of Fe and Mn bearing precipitates generated by Fe(II) and Mn(II) co-oxidation with O-2, MnO4 and HOCl in the presence of groundwater ions2019In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 161, p. 505-516Article in journal (Refereed)
    Abstract [en]

    In this work, we combined macroscopic measurements of precipitate aggregation and chemical composition (Mn/Fe solids ratio) with Fe and Mn K-edge X-ray absorption spectroscopy to investigate the solids formed by co-oxidation of Fe(II) and Mn(II) with O-2, MnO4, and HOCl in the presence of groundwater ions. In the absence of the strongly sorbing oxyanions, phosphate (P) and silicate (Si), and calcium (Ca), O-2 and HOCl produced suspensions that aggregated rapidly, whereas co-oxidation of Fe(II) and Mn(II) by MnO4 generated colloidally stable suspensions. The aggregation of all suspensions decreased in P and Si solutions, but Ca counteracted these oxyanion effects. The speciation of oxidized Fe and Mn in the absence of P and Si also depended on the oxidant, with O-2 producing Mn(III)-incorporated lepidocrocite (Mn/Fe = 0.01-0.02 mol/mol), HOCl producing Mn(III)-incorporated hydrous ferric oxide (HFO) (Mn/Fe = 0.08 mol/mol), and MnO4 producing poorly-ordered MnO2 and HFO (Mn/Fe > 0.5 mol/mol). In general, the presence of P and Si decreased the crystallinity of the Fe(III) phase and increased the Mn/Fe solids ratio, which was found by Mn K-edge XAS analysis to be due to an increase in surface-bound Mn(II). By contrast, Ca decreased the Mn/Fe solids ratio and decreased the fraction of Mn(II) associated with the solids, suggesting that Ca and Mn(II) compete for sorption sites. Based on these results, we discuss strategies to optimize the design (i.e. filter bed operation and chemical dosing) of water treatment plants that aim to remove Fe(II) and Mn(II) by co-oxidation.

  • 43.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Department of Environmental Technology, Wageningen University and Research (WUR), Wageningen, Netherlands.
    van der Wens, Patrick
    Brabant Water NV Breda, Breda, Netherlands..
    Baken, Kirsten
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    de Waal, Luuk
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Stuyfzand, Pieter
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands.;Delft Univ Technol, Dept Geosci & Engn, Delft, Netherlands..
    Arsenic reduction to < 1 mu g/L in Dutch drinking water2020In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 134, article id 105253Article, review/survey (Refereed)
    Abstract [en]

    Arsenic (As) is a highly toxic element which naturally occurs in drinking water. In spite of substantial evidence on the association between many illnesses and chronic consumption of As, there is still a considerable uncertainty about the health risks due to low As concentrations in drinking water. In the Netherlands, drinking water companies aim to supply water with As concentration of < 1 mu g/L - a water quality goal which is tenfold more stringent than the current WHO guideline. This paper provides (i) an account on the assessed lung cancer risk for the Dutch population due to pertinent low-level As in drinking water and cost-comparison between health care provision and As removal from water, (ii) an overview of As occurrence and mobility in drinking water sources and water treatment systems in the Netherlands and (iii) insights into As removal methods that have been employed or under investigation to achieve As reduction to < 1 mu g/L at Dutch water treatment plants. Lowering of the average As concentration to < 1 mu g/L in the Netherlands is shown to result in an annual benefit of 7.2-14 M(sic). This study has a global significance for setting drinking water As limits and provision of safe drinking water.

  • 44.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. SIBELCO, Ankerpoort NV, Op de Bos 300, 6223 EP, Maastricht, the Netherlands.
    van Genuchten, C. M.
    Department of Geochemistry, Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, Copenhagen, Denmark.
    Deep-dive into iron-based co-precipitation of arsenic: A review of mechanisms derived from synchrotron techniques and implications for groundwater treatment2024In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 249, article id 120970Article, review/survey (Refereed)
    Abstract [en]

    The co-precipitation of Fe(III) (oxyhydr)oxides with arsenic (As) is one of the most widespread approaches to treat As-contaminated groundwater in both low- and high-income settings. Fe-based co-precipitation of As occurs in a variety of conventional and decentralized treatment schemes, including aeration and sand filtration, ferric chloride addition and technologies based on controlled corrosion of Fe(0) (i.e., electrocoagulation). Despite its ease of deployment, Fe-based co-precipitation of As entails a complex series of chemical reactions that often occur simultaneously, including electron-transfer reactions, mineral nucleation, crystal growth, and As sorption. In recent years, the growing use of sophisticated synchrotron-based characterization techniques in water treatment research has generated new detailed and mechanistic insights into the reactions that govern As removal efficiency. The purpose of this critical review is to synthesize the current understanding of the molecular-scale reaction pathways of As co-precipitation with Fe(III), where the source of Fe(III) can be ferric chloride solutions or oxidized Fe(II) sourced from natural Fe(II) in groundwater, ferrous salts or controlled Fe(0) corrosion. We draw primarily on the mechanistic knowledge gained from spectroscopic and nano-scale investigations. We begin by describing the least complex reactions relevant in these conditions (Fe(II) oxidation, Fe(III) polymerization, As sorption in single-solute systems) and build to multi-solute systems containing common groundwater ions that can alter the pathways of As uptake during Fe(III) co-precipitation (Ca, Mg bivalent cations; P, Si oxyanions). We conclude the review by providing a perspective on critical knowledge gaps remaining in this field and new research directions that can further improve the understanding of As removal via Fe(III) co-precipitation.

  • 45.
    Ahmad, Zoe
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    An Assessment of the Swedish Bioeconomical Development2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Bioeconomy is an emerging term defined by the European Commission as ‘an economy based on biological,renewable resources to produce bioenergy, biobased products, services and food’. Unlike neighbouring countries Germany and Finland, Sweden lacks an official national bioeconomy strategy and the Swedish bioeconomical development is not mapped. Previous literature has not addressed the topic specifically and to do so, it was believed necessary to address relevant actors currently undergoing the bioeconomical development. It is investigated if the Swedish bioeconomical development is too slow and inefficiently regulated and if so, what measure can be taken. A literature study and 13 interviews with actors relevant to the bioeconomical transition were used to achieve the objective of the study. Concluded, the field of bioeconomy severely needs parameters to make its definition and quantification possible. Despite lacking a national bioeconomy strategy, Sweden’s bioeconomical development is not stalled. The government pursues the transition through specifically created institutions and big investments. Compared to Finland, Sweden performs well within the current bioeconomical sectors (biomass production and biobased sectors were assessed). Parameters must be established to enable a better mapping of the process and to complete the bioeconomical transition within Sweden.

    Download full text (pdf)
    fulltext
  • 46.
    Ahmadi Achachlouei, Mohammad
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC.
    Exploring the Effects of ICT on Environmental Sustainability: From Life Cycle Assessment to Complex Systems Modeling2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The production and consumption of information and communication technology (ICT) products and services continue to grow worldwide. This trend is accompanied by a corresponding increase in electricity use by ICT, as well as direct environmental impacts of the technology. Yet a more complicated picture of ICT’s effects is emerging. Positive indirect effects on environmental sustainability can be seen in substitution and optimization (enabling effects), and negative indirect effects can be seen in additional demand due to efficiency improvements (rebound effects).

    A variety of methods can be employed to model and assess these direct and indirect effects of ICT on environmental sustainability. This doctoral thesis explores methods of modeling and assessing environmental effects of ICT, including electronic media. In a series of five studies, three methods were at times applied in case studies and at others analyzed theoretically. These methods include life cycle assessment (LCA) and complex systems modeling approaches, including System Dynamics (SD) and agent-based (AB) modeling.

    The first two studies employ the LCA approach in a case study of an ICT application, namely, the tablet edition of a Swedish design magazine. The use of tablets has skyrocketed in recent years, and this phenomenon has been little studied to date. Potential environmental impacts of the magazine’s tablet edition were assessed and compared with those of the print edition. The tablet edition’s emerging version (which is marked by a low number of readers and low reading time per copy) resulted in higher potential environmental impacts per reader than did the print edition. However, the mature tablet edition (with a higher number of readers and greater reading time per copy) yielded lower impacts per reader in half the ten impact categories assessed.

    While previous studies of electronic media have reported that the main life-cycle contributor to environmental impacts is the use phase (which includes operational electricity use as well as the manufacture of the electronic device), the present study did not support those findings in all scenarios studied in this thesis. Rather, this study found that the number of readers played an important role in determining which life-cycle phase had the greatest impacts. For the emerging version, with few readers, content production was the leading driver of environmental impacts. For the mature version, with a higher number of readers, electronic storage and distribution were the major contributors to environmental impacts. Only when there were many readers but low overall use of the tablet device was the use phase the main contributor to environmental impacts of the tablet edition of the magazine.

    The third study goes beyond direct effects at product- and service-level LCAs, revisiting an SD simulation study originally conducted in 2002 to model indirect environmental effects of ICT in 15 European countries for the period 2000-2020. In the current study, three scenarios of the 2002 study were validated in light of new empirical data from the period 2000–2012. A new scenario was developed to revisit the quantitative and qualitative results of the original study. The results showed, inter alia, that ICT has a stimulating influence on total passenger transport, for it makes it more cost- and time-efficient (rebound effects).

    The modeling mechanism used to represent this rebound effect is further investigated in the fourth study, which discusses the feedback loops used to model two types of rebound effects in passenger transport (direct economic rebound and time rebound). Finally, the role of systems thinking and modeling in conceptualizing and communicating the dynamics of rebound effects is examined.

    The aim of the fifth study was to explore the power of systems modeling and simulation to represent nonlinearities of the complex and dynamic systems examined elsewhere in this thesis. That study reviews previous studies that have compared the SD and AB approaches and models, summarizing their purpose, methodology, and results, based on certain criteria for choosing between SD and AB approaches. The transformation procedure used to develop an AB model for purposes of comparison with an SD model is also explored.

    In conclusion, first-order or direct environmental effects of ICT production, use, and disposal can be assessed employing an LCA method. This method can also be used to assess second-order or enabling effects by comparing ICT applications with conventional alternatives. However, the assessment of enabling effects can benefit from systems modeling methods, which are able to formally describe the drivers of change, as well as the dynamics of complex social, technical, and environmental systems associated with ICT applications. Such systems methods can also be used to model third-order or rebound effects of efficiency improvements by ICT.

    Download full text (pdf)
    Cover essay for dissertation, Mohammad Ahmadi Achachlouei
  • 47.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC.
    Hilty, Lorenz M.
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC.
    Modeling the Effects of ICT on Environmental Sustainability: Revisiting a System Dynamics Model Developed for the European Commission2015In: ICT Innovations for Sustainability / [ed] Hilty, L.M.; Aebischer, B., Switzerland: Springer Publishing Company, 2015, p. 449-474Chapter in book (Refereed)
    Abstract [en]

    This chapter revisits a System Dynamics model developed in 2002 with the aim of exploring the future impacts of Information and Communication Technology (ICT) on environmental sustainability in the EU, which then consisted of 15 countries. The time horizon of the study was 20 years (2000–2020). We analyze the results in light of empirical data that is now available for 2000–2012. None of the three scenarios that were developed by experts to specify the external factors needed to run the model were realistic from today’s point of view. If the model is re-run with more realistic input data for the first half of the simulation period, however, the main results regarding the impact of ICT remain qualitatively the same; they seem to be relatively robust implications of the causal system structure, as it is represented in the model. Overall, the impacts of ICT for mitigating greenhouse gas emissions and other environmental burdens for 2020 tend to be slightly stronger if the simulation is based on the empirical data now available.

    Download full text (pdf)
    fulltext
  • 48.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC.
    Hilty, Lorenz M.
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC. Empa, Swiss Federal Laboratories for Materials Science and Technology. Department of Informatics, University of Zurich.
    Modelling Rebound Effects in System Dynamics2014In: Proceedings of the 28th Conference on Environmental Informatics - EnviroInfo 2014 - ICT for Energy Efficiency / [ed] Marx Gómez, J., Sonnenschein, M., Vogel, U., Winter, A., Rapp, B., Giesen, N., Germany: BIS Oldenburg, 2014Conference paper (Refereed)
    Abstract [en]

    The induction of demand by increasing the efficiency of a production or consumption process is known as the rebound effect. Feedback loops in System Dynamics can be used to conceptualize the structure of this complex phenomenon and also for communicating model-based insights. In passenger transport, the rebound effect can be induced through increased cost efficiency (direct economic rebound) and/or increase in speed (time rebound). In this paper we review and compare two models on environmental effects of passenger transport—including a model on the role of information and communication technology. We highlight the feedback mechanisms used to deal with the rebound effect (price, efficiency, and time rebound).

  • 49.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC. Empa, Swiss Federal Laboratories for Materials Science and Technology, Technology and Society Lab, St. Gallen, Switzerland.
    Hilty, Lorenz M.
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC. Swiss Federal Laboratories for Materials Science and Technology (Empa) and University of Zurich, Department of Informatics.
    System Dynamics vs. agent-based modeling—comparing models and approaches: A literature review and a transformation procedureManuscript (preprint) (Other academic)
    Abstract [en]

    Systems modeling and simulation methods such as System Dynamics (SD) and agent-based (AB) modeling have been used to foster a better understanding of the dynamics and complexity of natural, technical, and social systems. System Dynamics provides an aggregate-level perspective, highlighting thinking in feedback loops and employing differential equations to model the causal relations in a system, exploring the system's dynamics by numerically solving the equations. Agent-based modeling, in a bottom-up method, focuses on constituent units (agents) and their interactions to explore the emerging behavior at a system level by means of simulation. Comparing these modeling methods can help us understand their strengths and weaknesses in order to choose the right approach for a given modeling problem. It may also support the analysis of a given system to build multiple models using the different approaches and comparing them, in particular to treat fundamental uncertainties in systems modeling and simulation. In this paper, we review the existing studies comparing the SD and AB approaches and models, investigating the aims, methodology, and results of such comparative studies. We also highlight lessons learned for future model comparisons by examining how the corresponding SD and AB models are built for the purpose of comparison. A procedure for transforming System Dynamics models into agent-based models is presented and discussed using examples from the literature.

    Download full text (pdf)
    fulltext
  • 50.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). Empa – Swiss Federal Laboratories for Materials Science and Technology, Technology and Society Lab , 9014 St. Gallen, Switzerland .
    Hilty, Lorenz M.
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for Sustainable Communications, CESC. University of Zürich, , Department of Informatics, CH-8050 Zürich, Switzerland; Empa – Swiss Federal Laboratories for Materials Science and Technology, Technology and Society Lab , 9014 St. Gallen, Switzerland .
    Using Systems Thinking and System Dynamics Modeling to Understand Rebound Effects2016In: Advances And New Trends In Environmental And Energy Informatics / [ed] Jorge Marx Gómez, Michael Sonnenschein, Andreas Winter, Ute Vogel, Barbara Rapp Nils Giesen, Cham, Switzerland: Springer Publishing Company, 2016, p. 237-255Chapter in book (Refereed)
    Abstract [en]

    Processes leading to an increase of demand for a resource as a consequence of increasing the efficiency of using this resource in production or consumption are known as (direct) rebound effects. Rebound effects at micro and macro levels tend to offset the reduction in resource consumption enabled by progress in efficiency. Systems thinking and modeling instruments such as causal loop diagrams and System Dynamics can be used to conceptualize the structure of this complex phenomenon and also to communicate model-based insights. In passenger transport, the rebound effect can be invoked by increased cost efficiency (direct economic rebound) and/or increase in speed (time rebound). In this paper we review and compare two existing models on passenger transport—including a model on the role of information and communication technology—with regard to the feedback loops used to conceptualize rebound effects.

    Download full text (pdf)
    fulltext
1234567 1 - 50 of 3693
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf