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  • 101.
    Andersson, Karolina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Igensättning av långsamfilter i Östby vattenverk i Kramfors: studie av påverkande faktorer2006Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.

    The waterworks is a surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters. After the filters the water is alkalinized and disinfected before it reaches the customers.

    This thesis work has looked into which factors influence the clogging and trials have been made in order to optimize the waterworks and thereby reduce the clogging. The raw water has been studied with aspect to biology and chemistry, the filtered water has been studied with aspect to chemistry and also the pressures in the slow sand filters have been studied.

    The colour of the raw water from Sjöbysjön and its catchment area has increased since the beginning of the 90-ies and also the bio volume has increased in the lake.

    The contents of aluminium before the slow sand filters are far higher than the contents after, which leads to the conclusion that aluminium is accumulated in the filters. The differential pressure over the sand bed increases with time after a cleaning. This indicates an accumulation of particles which increases with the load. Observations of the filter surface before cleaning showed that it was covered by a brown, jelly-like film. The internal resistance in the filter beds increases successively after a cleaning and one month after cleaning it is highest in the upper part of the sand bed. All this points to that flocculated aluminium is gathered in the slow sand filters, on the surface, causing clogging.

    While the thesis work has been going on a process of alkalinizing before the contact filters has been reengaged and this has influenced the flocking of organic materials. When raising the pH the dose of flocculent was increased and this combined increased the amount of flocculated material. The contact filters could not bear this increased amount of flock load but showed instead a breakthrough.

    In a few lab scale trials the flocking pH was varied as well as the dose flocculent to the raw water and after this the water was filtrated. A tendency was seen that the separation of aluminium, colour and turbidity increased with increasing pH and dose flocculent. At the pH 6.2 and the chemical dose of 60 g/m3 the content of aluminium, the colour and the turbidity showed the lowest values in the filtrate.

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  • 102.
    Andersson, Lars-Olof
    Luleå University of Technology.
    Adhesion of ice to polymer materials1989In: Poac 89: 10th International Conference on Port and Ocean Engineering under Artic Conditions, Luleå, Sweden, 12-16 June 1989 / [ed] Lennart Å. Fransson; Kennet B. Axelsson, Luleå: Högskolan i Luleå , 1989, Vol. 2, p. 786-985Conference paper (Refereed)
  • 103.
    Andersson, Lars-Olof
    Luleå University of Technology.
    Ice accretion and ice adhesion to polymer material1993Licentiate thesis, comprehensive summary (Other academic)
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  • 104.
    Andersson, Lars-Olof
    et al.
    Luleå University of Technology.
    Golander, Car-Gustaf
    SKEGA AB.
    Persson, Sture
    SKEGA AB.
    Ice adhesion to rubber materials1994In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 8, no 2, p. 117-132Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate the interfacial shear strength between ice and rubbers. Different rubber materials containing only a polymer and curing agent (peroxide) were tested with regard to surface wettability and interfacial shear strength. The effect of different grades and amounts of carbon black filler was also studied. The wettability was determined from contact angles, using water and diiodomethane as test liquids, measured on carefully cleaned and mirror smooth rubber sheets.

  • 105.
    Andersson, Lisa
    et al.
    RISE - Research Institutes of Sweden (2017-2019).
    Larsson, Anders
    SLU, Sweden.
    Malm, Annika
    RISE - Research Institutes of Sweden (2017-2019).
    Sörelius, Helene
    RISE - Research Institutes of Sweden (2017-2019).
    Implementering av innovativa systemlösningar för hållbar dagvattenhantering2017Report (Other academic)
    Abstract [sv]

    Projektet Klimatsäkrade systemlösningar för urbana ytor syftar till att stärka städers förmåga att hantera ökad urbanisering och förändrat klimat, bland annat genom att utveckla innovativa systemlösningar för dagvattenhantering. I detta delprojekt har hinder och utmaningar för implementering av innovativa systemlösningar i stadsutvecklingsprocesser identifierats genom intervjuer med sakkunniga teknikexperter samt tjänstepersoner från olika förvaltningar. Som komplement har Svenskt Vattens publikationer P105 (Svenskt Vatten, 2011) och P110 (Svenskt Vatten, 2016) som är branschstandard för dagvattenhantering, samt utvalda kommuners policydokument analyserats för att undersöka hur dessa förhåller sig till innovativa systemlösningar för dagvattenhantering. Teoretisk utgångspunkt har varit studier kring vad som påverkar utveckling och spridning av tekniska innovationssystem (Bergek, 2008; Hellsmark, Bergek, Hellström, & Malmquist, 2014) samt teorier om innovation i offentlig sektor (Mulgan, 2007; Mulgan, 2014; Nählinder, 2013; Nählinder & Fogelberg Eriksson, 2017). De främsta faktorer som har identifierats påverka implementering av systemlösningar för dagvattenhantering är innovationskultur, samverkan vid planering, kunskap och ekonomi. För att överbrygga dessa hinder har rekommendationer för hållbar dagvattenhantering och uppdaterade riktlinjer för utformning av dagvattenstrategi utvecklats. För att underlätta samverkan samt val av dagvattenlösning har även ett beslutsstöd utvecklats för att kunna användas i ett tidigt skede vid planering (Brisvåg, 2017).

  • 106.
    Andersson, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Ökad grundvattenbildning genom pumpning av salt grundvatten från berggrunden på Gotland2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Because of an increased shortage and an increased demand of fresh water on Gotland, the possibility to pump saline groundwater and thereby locally lower the saltwater interface and increase recharge was investigated. With the saltwater interface further down in the bedrock, deeper wells could be drilled and extraction of more fresh water would therefore be possible.

    To examine the concept, a groundwater model was created to simulate the idea on a region of the peninsula Sudret on the southern part of the island of Gotland, Sweden. To be able to simulate the idea of pumping groundwater in an aquifer with a mix of saline and fresh groundwater of variable density, a model was built using the groundwater modelling program GMS in combination with the modules/program codes MODFLOW, MT3DMS and SEAWAT. With these modules, the model can handle the complex situation with extraction by pumping from groundwater of variable density and changes of salt concentration over time. A three dimensional geological model over the area produced by SGU was used as a foundation for building the model.

    Since no site specific surveys considering groundwater levels and flow/dispersion parameters have been previously undertaken in the study area, the parameters of the model were chosen according to literature and findings from similar projects conducted in the past. First, a model was developed to simulate a stable saltwater interface without pumps. Parameters were changed until a groundwater level close to the surface of the model was given and the saltwater interface ended up around the transition between limestone and sandstone. When the model generated desirable results, it was further developed to include the extraction of saltwater by pumping. 

    Results from the project showed that the concept of lowering the saltwater interface by pumping works, with an increased recharge corresponding to 55 % of the extracted saltwater volume. Because of a lack of site specific parameters, the results should not be seen as more than an indication that the concept works. 

    Furthermore, geohydrological measures should be made to provide local parameters regarding flow and dispersion for more reliable future models. To gain a greater understanding of how well the concept would work in reality, further development should be undertaken to include fresh groundwater extraction to assess how that would affect the position of the saltwater interface.

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  • 107. Andersson, O.
    et al.
    Hellström, Göran
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Recent UTES development in Sweden2000In: Proceedings: TERRASTOCK 2000, 8th International Conference on Thermal Energy Storage : University of Stuttgart, Germany, August 28th until September 1st, 2000 / [ed] Martin Benner, Stuttgart: Universität Stuttgart , 2000, p. 75-80Conference paper (Refereed)
  • 108. Andersson, Olle
    et al.
    Johansson, Sam
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Innovative and cost-effective cold storage applications in Sweden: IEA Annex 71994Report (Other academic)
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  • 109. Andersson, Olof
    et al.
    Hellström, Göran
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Heating and cooling with UTES in Sweden: current situation and potential market development2003In: Proceedings: Futurestock 2003, 9th International Conference on Thermal Energy Storage : Warsaw, Poland, September 1 - 4, 2003, Warszawa: PW Publishing House , 2003, p. 207-215Conference paper (Refereed)
    Abstract [en]

    Underground Thermal Energy Storage (UTES) applications have slowly gained acceptance on the Swedish energy market. Two UTES concepts are successfully implemented; the ATES (aquifer storage) and the BTES (borehole storage) systems. Also snow storage in pits or caverns has reached a commercial status. The number of ATES has steadily grown to 40 large-scale plants at the end of 2002. The systems are usually designed for cold storage in district cooling application, but industrial process cooling is also common. The economical potential in terms of straight payback time is usually very favourable. However, there is still a certain risk for operational problems that might jeopardize the calculated profit. Well clogging problems and system control remain as R&D issues to be solved. From a legislation point of view any ATES application needs a permit. The process of obtaining a permit has become complex and time-consuming since a new act on environmental assessment was put into effect in 1999.BTES systems are normally used in smaller applications. At the end of 2002 there were more than 200 installations comprising more than 10 boreholes. The majority of these are applied for space cooling of commercial or institutional buildings and for process cooling within the telecommunication sector. From a technical point of view, BTES are much simpler to construct and operate than ATES. Furthermore, they can be applied in almost any kind of geology. Another advantage compared to ATES is that the permitting procedure is much simpler. The major market obstacle is that the profitability is not always acceptable if calculated as a straight payback time. To increase the market potential, there is a need for further R&D on improvement of borehole heat exchangers and of more effective drilling methods.Snow storage is still a new technology though the Sundsvall snow storage plant has been operated successfully for several years. This good example has inspired several pre-studies of new snow storage plants. These have shown that snow storage is feasible in various sizes and in different applications.

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  • 110.
    Andersson, Rickard
    Jönköping University, School of Engineering, JTH, Civil Engineering.
    Dagvattenhantering inom starkt hårdgjord radhustomt med jord av begränsade infiltrationsegenskaper.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose: The problem with hard surfaces, as for example asphalt and roofing, is that they do not absorb enough rainwater. Furthermore, this leads to that grass surfaces and other absorbent surfaces around having to take care of all stormwater that the hardened surfaces cannot infiltrate. Flooding in urban environments has become increasingly common due to heavy rain and a high proportion of hard surfaces. This leads to an overload of the pipe line for rainwater. Therefore well-functioning balancing trays close to source needed to mimic natural drainage of nature. The goal was to investigate witch countervailing magazine mainly should be applied in heavily paved small terraced plots, where the soil has limited infiltration properties, in terms of efficiency, cost and maintenance.

    Method: The methods used to meet the objective is analysis of documents, qualitative interviews and a case study. The document analysis serves as a basis for the case study and interviews serve as empirical input for the case study.

    Findings: The countervailing magazine that is preferred is the pipe magazine when the plant surface is limited and the soil has limited infiltration properties.

    Implications: The problem statement treats the issue with an increasing number of floodings in urban environments due to the paved surfaces and the heavy rains. Furthermore, it is disclosed that the management system therefore risks becoming overloaded. This problem was also confirmed in the interviews. The work did not identify which countervailing magazine that is preferred for all kinds of cases, but only in the cases where land space is limited and where the soil has limited infiltration properties. The solution is therefore that pipe magazine is the magazine preferred for local disposal of stormwater in those circumstances. It is recommended when applying this result real life, to use the cost per meter and countervailing volume per meter available in efforts to work out how long stretch pipe magazine needs to be built on to achieve the desired equalization volume. Rating systems made for maintenance can however be used for other cases.

    Limitations: The result is applicable in similar scenarios as for the case study, which is at a row house site where the surface for the magazine is limited and where the soil has limited infiltration properties. A graph has been developed for the work where the construction cost per meter is described for each countervailing magazine and also has a graph with stormwater volume per meter been developed. These diagrams can therefore be applied to other cases with small areas but with other measures of the plot. Therefore the result also is applicable to other cases.

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  • 111.
    Andersson, Sandra
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bengtsson, Linn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utredning och analys av en vattenreservoars utformning och dimensioneringsprocess2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The essay contains an assessment of water reservoirs, where an examination and analysis of storage volumes and construction solutions are carried out. Today there are no clear guidelines for how reservoirs in smaller communities should be designed and dimensioned to ensure water quality and guarantee a safe water supply. The goal and purpose of the essay is to calculate a storage volume, identify important aspects to consider in designing a reservoir, and present advantages with and the need of a water reservoir based on consumption variations. The assessment is limited to Lammhults’s conditions where interviews, observations, literature studies, analyses and calculations serve as a foundation for the theory and the result. The result demonstrates, among other things, difficulties, difficulties in analyzing consumption variations, the importance of local correct statistics and questioning of existing methods of dimensioning a storage volume. The essay partially some problem areas, but further studies are required to find solutions in the sector and straight guidelines regarding dimensions and design of reservoirs. 

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  • 112.
    Andersson, Simon
    et al.
    Mälardalen University, School of Business, Society and Engineering.
    Callin, Veronika
    Mälardalen University, School of Business, Society and Engineering.
    SMÅSKALIG VATTENKRAFT OCH FLEXIBILITET I ELSYSTEMET: En kartläggning av förväntningarna på den småskaliga vattenkraftens potential att bidra med flexibilitet.2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 113.
    Andersson, Sofia Lovisa
    et al.
    IVL Swedish Environmental Research Institute.
    Westling, Klara
    Andersson, Sofia
    Karlsson, Jesper
    IVL Swedish Environmental Research Institute.
    Narongin, Mayumi
    IVL Swedish Environmental Research Institute.
    Carranza Munoz, Andrea
    IVL Swedish Environmental Research Institute.
    Bornold, Niclas
    IVL Swedish Environmental Research Institute.
    Baresel, Christian
    IVL Swedish Environmental Research Institute.
    Long term trials with membrane bioreactor for enhanced wastewater treatment coupled with compact sludge treatment -pilot Henriksdal 2040, results from 20202021Report (Other academic)
    Abstract [en]

    Stockholm’s wastewater treatment plant (WWTP) in is currently retrofitting from a conventional activated sludge process to a new membrane bioreactor (MBR) process. It also includes new treatment steps for sludge handling. Stockholm Vatten och Avfall (SVOA) and IVL have since 2014 conducted long-term MBR studies in pilot scale at the R&D facility Hammarby Sjöstadsverk. This report present results from the pilot operation during 2020. 

    The MBR-pilot was continuously operated at a higher inflow than the design average flow. The average effluent concentration of nitrogen and phosphorus met the effluent requirements of the future WWTP also this year. A low consumption of phosphorus precipitation chemicals could be achieved mainly due to a high Bio-P activity. The pilot showed that glycerol can be a good temporary carbon source at Henriksdal WWTP during startup. 

    Like previous years, the membranes in membrane tank 1 (MT1) was cleaned with oxalic acid and the membranes in MT2 with citric acid. Several tests to optimize the chemical consumption for membrane cleaning were performed. Recovery cleanings (RC) of the membranes were performed twice in 2020.

    In the sludge pilot, a thermophilic and a mesophilic hydraulic retention time (HRT) crash test showed stable performance down to 4 days HRT. 

    The overall resource consumption in the pilot showed that the optimization of phosphorus precipitation and membrane cleaning chemicals resulted in a significantly lower dosing than design values for the future Henriksdal WWTP. 

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  • 114. Andersson, Sören
    et al.
    Abyhammar, Tomas
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Full-scale multiple well heat storage system for experiment and demonstration1983In: Proceedings - International Conference on Subsurface Heat Storage in Theory and Practice, Statens råd för byggnadsforskning , 1983, p. 610-615Conference paper (Refereed)
  • 115.
    Andersson, Sören
    et al.
    AIB Consulting Engineers.
    Eriksson, Anders
    AIB Consulting Engineers.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Heat storage in rock: multiple well system1981Report (Other academic)
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  • 116. Andersson, Sören
    et al.
    Eriksson, Anders
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Säsongslagring av värme i berg1981In: Byggnadskonst, ISSN 0007-7593, Vol. 73, no 11, p. 45-47Article in journal (Other (popular science, discussion, etc.))
  • 117.
    Andersson, Sören
    et al.
    Swedish Council for Building Research.
    Johansson, Alf
    Swedish Council for Building Research.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Åbyhammar, Tomas
    Swedish Council for Building Research.
    A borehole heat store in rock: pilot trials in Luleå and preliminary design of a full-scale installation1983Report (Other academic)
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  • 118.
    Andersson, Sören
    et al.
    AIB Stockholm.
    Johansson, Alf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Åbyhammar, Tomas
    AIB Stockholm.
    Värmelagring i berg med borrhålssystem: Pilotförsök i Luleå och förprojektering av fullskaleanläggning1986Report (Other academic)
  • 119. Andersson, Sören
    et al.
    Åbyhammar, Tomas
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Multiple well system for seasonal heat storage at Luleå1983In: Väg- och Vattenbyggaren, ISSN 0042-2177, no 4, p. 10-11Article in journal (Other (popular science, discussion, etc.))
  • 120.
    Andersson-Chan, Anneli
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    A rockwool biofilter for the treatment of restaurant emissions2000Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over the past 20 years, the use of biological air pollution control has become a popular treatment alternative for contaminated gas streams. The objective of this licentiate thesis was to investigate the feasibility of a compact rockwool biofilter to treat emissions from a restaurant, to identify an appropriate microbial population for the inoculation of the biofilter, and suitable environmental conditions for this culture. Rockwool mats with pre-set structures were shown to have a good structural stability, developed low pressure drop, did not compact, and seemed to be a appropriate habitat for microorganisms. Bacteria from different environments were enriched in batch cultures; it was found that all cultures were able to oxidize rape-seed oil. Nutrients, mainly phosphorus and nitrogen, must be added occasionally to the bacterial culture. Clogging due to high depositions of grease could be prevented by using a mechanical collector installed upstream of the biofilter. The off-gas from the fryer consisted of a complex mixture of partially oxidized hydrocarbons and the short residence times (<10 s) provided in the filter were not sufficient to achieve a significant reduction of aldehydes or fatty acids.

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  • 121.
    Andersson-Chan, Anneli
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Attempted biofiltration of reduced sulphur compounds from a pulp and paper mill in Northern Sweden2006In: Environmental progress, ISSN 0278-4491, E-ISSN 1547-5921, Vol. 25, no 2, p. 152-160Article in journal (Refereed)
    Abstract [en]

    The objective of this study was to identify the reduced sulphur compounds (RSCs) present in waste gas from a specific deaerator at a pulp and paper mill in northern Sweden, and to investigate the feasibility of a multi-stage biofilter to treat these compounds in an industrial setting. Two filter media, rockwool mats and an organic peat and compost mixture, were used as biofilter media. A mixed population of heterotrophs and a strain of Hypomicrobium were examined for DMS and DMDS degradation. Two experimental periods were performed for 45 days each, in the fall and winter in cold climate. Process parameters as well as the number of viable cells of the filter were monitored during operation. Results were inconsistent due to the fluctuations of the system, and a number of operational problems were identified, differing from those developed under controlled, laboratory set-ups. Process conditions varied greatly, that is, fluctuating temperatures, pollutant concentrations, and airflows that led to insufficient residence times. Both biological and mass transfer limitations are possible explanations for the poor treatment results. This study can contribute to assessing the feasibility of biofilters in the pulp and paper industry, and help reduce the knowledge gap between laboratory studies and field conditions.

  • 122.
    Andersson-Chan, Anneli
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Biofiltration of odorous gas emissions2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biofiltration has shown its potential as an interesting treatment alternative for contaminated gas streams. Unlike conventional technologies, such as adsorption, scrubbers, and incineration, biofiltration offers effective pollution control at relatively low capital and operating costs, and without the generation of secondary pollution that may require subsequent treatment. The disadvantages of biofiltration have been the large space requirements and frequent media replacements as a result of deterioration or ageing. Extensive biofilter research and development have taken place over the past 20 years internationally, in particular laboratory experiments that address the removal of single pollutants at fairly high concentrations under constant operating conditions. In field applications, such conditions are highly unusual and the feasibility of treating complex mixtures at very low concentrations relevant to many odorous gas emissions has not received much attention. The overall objective of this thesis was to reduce the knowledge gap between laboratory studies and field conditions on the topic of biofiltration for odorous gas emissions. Various operational and process related problems, such as fluctuating flows, temperatures, and pollutant concentrations, that affected the biofilter performance by creating suboptimal living conditions for the microbes were identified. A newly designed compact pilot-scale biofilter was used in three different applications with odour problems, namely restaurant, pulp mill and wastewater pumping station. The gas streams were complex mixtures with chemically diverse contaminants whose concentrations varied significantly with time. Aldehydes were the dominant compounds in restaurant emissions, while reduced sulphur compounds, primarily dimethyl sulphide, dominated the pulp mill and wastewater emissions. Overall, very low concentrations of individual compounds were found (ppb-level), and very low or no removal of the targeted compounds was achieved in the biofilter. Limitations of the biomass density in the filter media is a plausible explanation since pollutant concentrations at the ppb-level may have been too low to build up and support the bacteria. Due to the low solubility of many identified compounds, a mass transfer limitation may also have occurred due to the prevailing short residence times. Drying of the filter medium was partly a problem, pointing to the need for an improved humidification system or using a trickling filter design. In a case study at a wastewater treatment plant, a method to evaluate odour problems was developed involving local observers in an odour panel together with operational data and weather observations. Working with an odour panel proved useful in several ways; they took an active interest in and increased their knowledge of the complexity of odour problems. However, relating the panel reports to specific events at the treatment plant proved difficult, and the reports were not always consistent with current wind directions.

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  • 123.
    Andersson-Chan, Anneli
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Evaluation of a Rockwool biofilter media for odorous waste gas treatment2006In: 2006 Conference of the Water Environment Federation and the Air and Waste Management Association on Odors and Air Emissions, Connecticut Convention Center, Hartford, Connecticut (USA), 9-12 Apr 2006, WEF , 2006Conference paper (Other academic)
  • 124.
    Andersson-Chan, Anneli
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Bäckström, Magnus
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hanaeus, Jörgen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kompetens för driftspersonal vid VA-verk: Bakgrund och utveckling2006Report (Other academic)
    Abstract [en]

    The competence of operators at Swedish water and wastewater treatmentplants is analysed and sorted into four groups. A basis for future educationand continued education is discussed in relation to selected factors ofdevelopment for the surrounding world.

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  • 125. Andersson-Chan, Anneli
    et al.
    Grennberg, Kerstin
    Luleå University of Technology.
    Isolation and characterization of a bacterial population from a biofilter treating waste gases2001In: Environmental Engineering Science, ISSN 1092-8758, E-ISSN 1557-9018, Vol. 18, no 4, p. 237-248Article in journal (Refereed)
    Abstract [en]

    Biofiltration units are microbial ecosystems for the treatment of low-concentration, biodegradable waste gases. The aim of this work was to isolate and characterize an appropriate microbial culture for inoculation of a rockwool biofilter that treats waste gases from a fast-food restaurant using rape-seed oil in its frying process. Batch cultures from three various bacterial sources were studied under different chemical and physical conditions and compared to the growth of Bacillus sp. All cultures were able to degrade rape-seed oil and its oxidation products, with a simultaneous pH decrease in the batch cultures. It was necessary to add a salt medium containing, for example, phosphorus and nitrogen to obtain maximum growth. An exponential growth phase during a period of 3 to 8 days, with generation times of 9 to 33 h, was followed by slower growth. After a stationary phase of 25 to 40 days, the bacterial number started to decrease, probably due to substrate and/or oxygen depletion, or unfavorable pH. The rockwool biofilter material did not inhibit the growth of the bacterial cultures, and seemed to have a buffering capacity, which could prevent acidification of a future biofilter. The isolated bacteria from the mixed culture were found to be mesophilic, aerobic, Gram-negative rods.

  • 126.
    Andersson-Chan, Anneli
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hanaeus, Jörgen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Odorous wastewater emissions2006In: Vatten, ISSN 0042-2886, Vol. 62, no 3, p. 227-236Article in journal (Refereed)
    Abstract [en]

    The objective of this article is to review odour problems of wastewater treatment facilities and air emission treatment methods. The malodorous wastewater emissions consist of a complex mixture of substances with different properties. A screening of volatile organic and reduced sulphur compounds revealed very low concentrations of individual compounds (< 50 ppb), and only dimethyl sulphide, hydrogen sulphide and methyl mercaptan were found at concentrations above threshold values. Indicating one single compound responsible for the foul odours was not possible. Two case studies are presented and discussed. In the first, a compact biofilter was evaluated for the treatment of gas streams from a sewage pumping station. A rockwool filter media was inoculated with a mixed bacterial wastewater culture that established successfully. However, evaluating the biofilter's performance proved analytically difficult and expensive due to the low concentrations of incoming gases. In the second case study the odour nuisance situation around a wastewater treatment plant was evaluated and a holistic approach to manage the odour problems was developed. An odour panel of local observers worked well, since they got involved in the process. However, using the panel's reports on odour episodes to find the source of the odour was difficult.

  • 127. Andersson-Chan, Anneli
    et al.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    VVS 2000: tabeller och diagram : Vatten- och avloppsteknik2004Book (Other (popular science, discussion, etc.))
  • 128.
    Andersson-Wikström, Alexandra
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    The release of pollutants from roofing materials in laboratory experiments2015Conference paper (Refereed)
    Abstract [en]

    Diffuse pollution sources have been recognised by the European Water Framework Directive to significantly contribute to pollution of stormwater receivers. Stormwater runoff is considered to represent diffuse pollution sources. The aim of this study was to clarify the contributions of specific sources in the urban environment to the content of organic and inorganic pollutants in stormwater. This was done by conducting laboratory screening tests of several conventional roofing materials and coatings to determine which pollutants they release and how they might contribute to the deterioration of stormwater quality. The studied pollutants include metals (Cd, Cr, Cu, Ni, Pb, V, Zn) as well as polycyclic aromatic hydrocarbons (PAHs), phthalates, pesticides, nonylphenols and –ethoxylates. Many of the studied roofing materials, e.g. roofing shingle, a PVC sheet and a bitumen paste for felt roof maintenance, exhibited the potential to release several of these substances into stormwater runoff. However, phthalates were not released from any of the studied materials under the tested conditions. In addition, quite similar materials exhibited rather different substance release profiles.

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  • 129.
    Andersson-Wikström, Alexandra
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Size fractionation of dissolved metals in stormwater in Umeå, Sweden2016Conference paper (Refereed)
    Abstract [en]

    Dissolved metals are generally considered the most mobile, toxic and bioavailable form of metals. However, the partition between dissolved and particulate phases is conventionally defined by the fraction passing through a 0.45 μm membrane, even though it is widely known that this fraction also includes different types of organic and inorganic colloids. Further size fractionation of metals in the dissolved phase can be performed using different techniques. The knowledge on the metal fractionation in stormwater is useful for assessments of the metals’ bioavailability as well as the performance of stormwater treatment systems. In this study, the size fractionation of dissolved metals in stormwater from four different urban areas in the city of Umeå, Sweden, is determined using ultrafiltration. The objective is to find a pattern for the size fractionation of different metals in the dissolved phase in stormwater and, by this, estimate the bioavailability of the metals. The investigated catchment areas include a parking space, a highway and two different commercial sites. The sampling campaigns will take place in the spring of 2016, taking samples from the stormwater drainage system using automatic samplers.

  • 130.
    Anderzon, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    A valuation of ecosystem services from blue-green infrastructure for stormwater management2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The ongoing urbanization leads to densification and growth of cities, which replaces natural areas with hard surfaces. Precipitation is then more likely to runoff as stormwater than to be detained locally. Also, precipitation is predicted to be increasing as an effect of climate change. Traditionally, stormwater has been handled by draining it in underground pipes. As a complement, blue-green infrastructure (BGI) can be used to take care of the increased amount of stormwater. BGI is vegetation and water-based systems that intend to restore the natural flows of water. It does, however, not only provide services for stormwater management but also other services that contribute to human welfare. These are provided for free by nature and are called ecosystem services. By illustrating the value of ecosystem services, the motivation of implementing more BGI can increase. The aim of this project was to provide guidance on how to value ecosystem services that BGI can provide at a district level. The valuation was to be semi-quantitative with the grades 1-5. To do so, ecosystem services were identified and given indicators that could illustrate the extent of the ecosystem services’ presence.

    Seven different BGI for stormwater management were studied, to determine which added values they can bring into urban settings. The BGI were green roofs, trees, rain gardens, swales, detention basin, detention ponds and attenuation storage tanks. Nine ecosystem services provided by these BGI were then identified. These were flood protection, water treatment, local climate regulation, air quality control, environmental noise control, erosion prevention, recreation, social relations and biodiversity. 

    Indicators were identified for each ecosystem service through a literature study. It was noted that to value the ecosystem service, it was not enough to only value the presence of the indicators but also necessary to estimate the demand or need for the ecosystem service. Therefore, questions were formed that could help determine the demand for the ecosystem service. The valuation was then based on how well the presence of the ecosystem service corresponded to the demand of it. 

    After using this valuation method on a case study, it was concluded that this type of valuation is useful for reconstruction projects in an early stage, to illustrate what functions and demands that need to be considered to obtain more ecosystem services. It can then be used for comparison of different proposals, to see which one provides the most ecosystem services. The valuation is conceptual rather than specific. It is useful as it can include any type of ecosystem service but lacks the perspective of costs.

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  • 131.
    Andreasson, Patrik
    Luleå University of Technology.
    A numerical investigation of energy conversions in geophysical boundary layers1991Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The detailed energy conversions in turbulent geophysical boundary layers are examined and quantified. The governing transport equations are solved by utilizing turbulence modelling. Different turbulence closures have been adopted for the boundary layers examined. LowReynolds number modelling is required, since energy conversions are large in the near-wall region. The three examined boundary layers are: open channel flow, wind-induced countercurrent flow, and ice-covered channel flow. In addition, a generalized eddy-viscosity hypothesis is proposed. In the standard eddy-viscosity concept. zero shear stress coincides with zero shear. This is not realistic for many flows. such as wind-induced countercurrent Row. This limitation is relaxed in the new hypothesis, by recognizing the influence of gradients in the turbulent length scale and the shear. In open channel flow, energy is released to the kinetic energy of the mean flow by the lowering of the centre of mass. Between 20-70 % (depending on the Reynolds number) of the energy is dissipated by viscous forces working directly on the mean shear. The remaining portion is a source of turbulent kinetic energy, which is balanced by the dissipation. Eventually all of the energy will leave the domain as a boundary beat flux. In the modelling of open channel flow, a one-equation turbulence model and Reynolds analogy is used. In wind-induced countercurrent flow. energy is supplied to the mean flow by the wind acting on the free surface. Most of the mean kinetic energy is dissipated or transformed to turbulent kinetic energy in the surface drift current. Only about 5-10 % is supplied to the return flow underneath. As with open channel flow, 20-70 % of the mean kinetic energy is dissipated without entering the turbulent kinetic energy budget. The dissipated heat is considered to leave the domain through the free surface. A Reynolds stress model was adopted for the windinduced boundary layer, in conjunction with the "generalized gradient diffusion hypothesis" for beat flux. A detailed description is presented, of the spatial distribution and the depth-averaged features of energy conversions in the two boundary layers mentioned above. In the study of ice-covered channel flow, the analysis is focused on beat transfer characteristics. In water of a temperature close to 00C, the conversion from kinetic energy to heat may be of influence to the heat transfer in an ice-covered channel. In water of higher temperatures buoyancy effects may develop. In addition the melting ice-cover constitutes a moving boundary problem. These three effects are considered in the study, in which the predicted beat transfer characteristics are presented as Nusselt number relations. To make adequate predictions of the boundary layer flow beneath an ice-cover, a Reynolds stress and heat flux transport model is employed. Equations for the transport of temperature variance and its dissipation rate are also solved.

  • 132.
    Andreasson, Patrik
    Luleå University of Technology.
    Energy conversions in turbulent wind-induced countercurrent flow1992In: Journal of Hydraulic Research, ISSN 0022-1686, E-ISSN 1814-2079, Vol. 30, no 6, p. 783-800Article in journal (Refereed)
    Abstract [en]

    A detailed analysis of energy conversions and fluxes in wind-induced countercurrent flow is provided. At the free surface mechanical energy is supplied to the waterbody by the wind. Via stages of pressure-volume work and kinetic energy (divided into a mean and a fluctuating part), the energy will ultimately leave the flow as a surface heat flux. The analysis is based on mathematical modelling, supported by order-of-magnitude estimates and comparisons with reported experimental studies. A Reynolds-stress model, extended into the viscous sublayers, was required to predict adequately the mean velocity and turbulence structure of countercurrent flow.

  • 133.
    Andreasson, Patrik
    Luleå University of Technology.
    Luleå innerfjärdar: Rapport B: Hydrologi1996Report (Other academic)
  • 134.
    Andreasson, Patrik
    Luleå University of Technology.
    Open channel flow of hyperconcentrated suspensions: Viscous effects and aspects on the carrying capacity of particles1989Licentiate thesis, comprehensive summary (Other academic)
  • 135.
    Andreasson, Patrik
    et al.
    Luleå University of Technology.
    Hammar, Lars
    Luleå University of Technology.
    Shen, Hung Tao
    Luleå University of Technology.
    Influence of surface turbulence on the formation of ice pans1998In: Ice in Surface Waters: proceedings of the 14th International Symposium on Ice, Potsdam, New York, USA, 27-31 July 1998 / [ed] Hung Tao Shen, Rotterdam: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 1998, Vol. 1, p. 69-76Conference paper (Refereed)
  • 136.
    Andreasson, Patrik
    et al.
    Luleå University of Technology.
    Sellgren, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    River flow with excessive suspended sediment load: an evaluation of turbulent flow characteristics1986In: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 17, no 4-5, p. 383-390Article in journal (Refereed)
    Abstract [en]

    River flows with high volume concentrations (20-50%) of silty sediments generally imply that the mixture has non-Newtonian properties. In this study, the rheological behavior of mixtures with solids particles smaller than 0. 1 mm was identified experimentally with viscosimeters. Characteristic flow parameters, such as energy losses and depths, were then determined in several examples for turbulent open channel flows.

  • 137.
    Andreasson, Patrik
    et al.
    Luleå University of Technology.
    Svensson, Urban
    Luleå University of Technology.
    A note on a generalized eddy-viscosity hypothesis1992In: Journal of Fluids Engineering, ISSN 0098-2202, E-ISSN 1528-901X, Vol. 114, no 3, p. 463-466Article in journal (Refereed)
    Abstract [en]

    The standard eddy-viscosity concept postulates that zero velocity gradient is accompanied by zero shear stress. This is not true for many boundary layer flows: wall jets, asymmetric channel flows, countercurrent flows, for example. The generalized eddy-viscosity hypothesis presented in this paper, relaxes this limitation by recognizing the influence of gradients in the turbulent length scale and the shear. With this new eddy-viscosity concept, implemented into the standard k - ε model, predictions of some boundary layer flows are made. The modelling results agree well with measurements, where predictions with the standard eddy-viscosity concept are known to fail.

  • 138.
    André, Erik
    et al.
    Luleå University of Technology.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Dagsljus i ledningarna2003In: Energi och miljö, ISSN 1101-0568, no 2, p. 60-62Article in journal (Other academic)
  • 139.
    Anh Nguyen, Viet
    et al.
    HUCE, Vietnam.
    Phuong Nguyen, Minh
    VNU Univ Sci, Vietnam.
    Tonderski, Karin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Do Thi, Hai
    HUMG, Vietnam.
    Thi Kim Bui, Anh
    Vietnam Acad Sci and Technol, Vietnam.
    Design and performance of a coarse media, high hydraulic load polishing wetland for steel industry wastewater2019In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 80, no 1, p. 59-66Article in journal (Refereed)
    Abstract [en]

    This paper presents the design of a constructed wetland (CW) system in an area with limited land availability, resulting in high hydraulic loads. The CW was constructed to act as a buffering/polishing step after stabilization ponds for steel industry wastewater post-treatment. A pilot test with two different filter media (50-100 mm vs 40-60 mm diameter) indicated that a flow rate increase from 49.5 m(3)/h to 122.4 m(3)/h would lead to a head loss increase from 2.9 cm to 8.7 cm, and more than double that for the finer gravel. This was substantially higher than the calculated theoretical values, though the relation with flow rate was similar. Four full scale wetland cells (CW1, CW2, CW3 and CW4) were constructed using the coarser gravel. A design value of total head loss of 1.01 m over the total system length, with a design flow of 36,000 m(3)/day, was expected based on pilot test results. During the first operation year (September 2017 to July 2018), the pond-CW system has received wastewater already meeting required discharge standards. The effluent from the CWs had consistently lower concentrations of all measured variables, and met the predicted values for biochemical oxygen demand (BOD5), total nitrogen (TN) and NH4+-N. Highest removal efficiencies were achieved for NH4+-N (amp;gt; 90%), Mn (amp;gt; 60%) and Fe (45%) with removal efficiencies for TN (14%), BOD5 and chemical oxygen demand (COD) (around 30%). Concentrations of phenol, CN- and Cr6+ were below 10, 4 and 3 mu g/l, respectively, in in- and outflows. An appreciated benefit of the wetland was the green element in the industrial landscape.

  • 140.
    Annaduzzaman, Md
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Chitosan biopolymer as an adsorbent for drinking water treatment: Investigation on Arsenic and Uranium2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In many countries over the world (including Sweden), metal toxicity in freshwater resources causes a severe drinking water quality problem and poses a threat to the environment and human health. Among the different toxic metals in the water resources of Sweden, arsenic and uranium are the biggest threats to health. These elements, over long time consumption, may even lead to cancer and/or neurological disorder. Most of the wells are installed in crystalline and sedimentary bedrock and the received water comes from water bearing fractures in the bedrock. The handling of such water is an issue and there is a need to reduce the arsenic and uranium exposure by improving processes and technologies. It is a very serious problem demanding a safe, sustainable and eco-friendly arsenic and uranium removal technology prior to drinking water supply. Different treatment systems are available, but many of them are not suitable due to their high cost, operation complexity and waste management issues. Through this study, chitosan biopolymer the second largest abundant polysaccharide on earth after cellulose, was verified as a potential adsorbent for arsenic(V) and uranium(VI) removal from water solution. Adsorbent characterizations were also conducted by XRD, FTIR, SEM, UV-visible spectrum and TGA/DTA investigations. Bench-scale batch experiments were conducted using chitosan biopolymer (DDA-85%) as an adsorbent to determine the arsenic(V) and uranium(VI) removal efficiency, by allowing four important effective parameters e.g. chitosan dosages, pH, contact time and contaminant concentration. The adsorption data at optimum conditions were fitted with Langmuir, Freundlich and Dubinin-Radushkhevic (D-R) isotherm and Lagergren pseudo-first-order and pseudo-second-order kinetic model to investigate the adsorption process. The characterization of materials assured the presence of effective amino, hydroxyl, and carboxyl groups of chitosan. Another advanntage is that the materials are bio-degradable. The results show that the arsenic(V) and uranium(VI) removal efficiency was 100% and 97.45% after 300 minutes with optimum pH of 6.0 and 7.0 respectively. The optimum adsorbent dosages and initial concentration were 60 and 80g/L and 100 and 250 µg/L respectively. The adsorption process was suitably described by Freundlich isotherm (R2 = 0.9933) and Langmuir isotherm (R2 = 0.9858) correspondingly for arsenic(V) uranium(VI) compared to other isotherms. This is an important indicator of homogeneous monolayer adsorption of metals. For both of arsenic(V) and uranium(VI), pseudo-second-order explained the adsorption kinetics better than pseudo-first-order and the second-order kinetic regression coefficient (R2) were 0.9959 and 0.9672 correspondingly. Connecting to the above mentioned results, it can be summed up that the chitosan biopolymer (DDA 85%) can be used as an inexpensive, sustainable and environment-friendly treatment option for arsenic(V) and uranium(VI) contaminated drinking water.

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    Annaduzzaman, M. (2015)
  • 141.
    Anttila, Malin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Lokalt omhändertagande av dagvatten: Hantering av dagvattenfrågor i detaljplaner2019Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Dagvatten kan medföra stora problem om det inte hanteras på rätt sätt, det kan leda till skador på byggnader och vägar. I och med att större ytor i samhället hårdgörs kan inte dagvattnet infiltrera ner i marken och därför måste det tas omhand på andra sätt. Ofta när det skrivs detaljplaner så vill kommunen att vattnet ska tas omhand lokalt på fastigheten. Att omhänderta vattnet lokalt är väldigt bra för både grundvattennivån och om det är ett kombinerat avloppssystem. Dock är det ofta ett problem att det inte finns plats på fastigheten för att ta omhand dagvattnet lokalt på ett bra sätt. Hur dagvattensfrågorna hanteras skiljer sig stort mellan olika kommuner. De större kommunerna har ofta kommit mycket längre i utvecklingen i hanteringen av dagvatten i detaljplaner. I många mindre kommuners detaljplaner står det väldigt lite om på vilket sätt som dagvattnet ska tas omhand lokalt, oftast står det bara att vatten ska tas omhand lokalt på fastigheten. I de större kommunernas detaljplaner är det ofta lite mer utförligt hur dagvattnet ska hanteras lokalt och kanske till och med några exempel. Det är många delar som ska gå ihop i en detaljplan, och för mindre kommuner är det svårt att ha tillräckligt med kompetens inom alla delar. Men det krävs att det blir en förändring då det byggs mer hela tiden och fler ytor blir hårdgjorda så att naturlig infiltration inte kan ske. Även klimatet ändras och vi kommer mest troligt få ett större skyfall oftare. Piteå har under en 17-årsperiod varit drabbat av två stycken ordentliga skyfall där deras dagvattenhantering inte har klarat av att leda bort allt vatten som har kommit. Om kommunerna inte blir bättre på att ta omhand dagvattnet kommer det blir mycket skador som kostar enorma summor att åtgärda.

  • 142.
    Ardakani, Amir Hossien Hatefi
    et al.
    Univ Semnan, Coll Nat Resources & Desert, Dept Management Arid & Desert Reg, Semnan, Iran..
    Shojaei, Saeed
    Univ Tehran, Fac Nat Resources, Dept Arid & Mt Reg Reclamat, Tehran, Iran..
    Shahvaran, Ali Reza
    Iran Univ Sci & Technol, Sch Civil Engn, Tehran, Iran..
    Kalantari, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. Stockholm Univ, Dept Phys Geog, S-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, S-10691 Stockholm, Sweden..
    Cerda, Artemi
    Univ Valencia, Dept Geog, Soil Eros & Degradat Res Grp, Blasco Ibanez 28, Valencia 46010, Spain..
    Tiefenbacher, John
    Texas State Univ, Dept Geog, San Marcos, TX USA..
    Selecting potential locations for groundwater recharge by means of remote sensing and GIS and weighting based on Boolean logic and analytic hierarchy process2022In: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 81, no 1, article id 8Article in journal (Refereed)
    Abstract [en]

    Growing demand for water, as a consequence of population growth, farmland irrigation, and industrial expansion, results in groundwater resources exploitation. This, in combination with droughts induced by climate change, has caused a sharp drop in groundwater levels throughout arid and semiarid countries. In Iran, all these factors are resulting in alarming water scarcity. Appropriate management and control of existing water resources can overcome water shortages, with healthy and sustainable management of groundwater as one of the most efficient tools. Artificial recharge of aquifers can be used to replenish water supplies and restore the water resources in Iran and other semiarid and arid countries, but selection of the right location for runoff collection is essential to achieve success. Precipitation, slope, geology, lineament density, drainage density, aquifer water quality, groundwater level, vegetation, and land use were selected in this study as key factors in locating suitable sites for artificial recharge. The weight of each, in terms of importance and impact on aquifer recharge, was determined using remote sensing techniques to prepare layers and analytic hierarchy process (AHP) and Boolean logic to identify the optimal weight for each factor. Geographic information system (GIS) was used for modeling, applying the weight of each criterion, and producing a final map. The results showed better performance of AHP than Boolean logic. For artificial recharge, 9.9% of the total study area (Mahdishahr in northern Iran) was found to be in a very good position and 22.6% in a good position. On filtering the privacy layer of fountains and aqueducts, the very good and good area declined to 8.4% and 14.7% of the total area, respectively, and mainly comprised alluvial valleys and coarse alluvial sediments with low slope and drainage density.

  • 143.
    Arnell, Magnus
    RISE - Research Institutes of Sweden, Built Environment, Energy and Circular Economy.
    Implementation of the Bürger-Diehl settler model on the benchmark simulation platform2015Report (Other academic)
  • 144.
    Arnell, Magnus
    Lunds universitet, Sweden.
    Performance assessment of wastewater treatment plants: multi-objective analysis using plant-wide models2016Doctoral thesis, monograph (Other academic)
    Abstract [en]

    As the knowledge about anthropogenic impacts of climate change has grown, the awareness of the contributions from treatment of wastewater has widened the scope for wastewater treatment plants (WWTPs). Not only shall ever stricter effluent constraints be met, but also energy efficiency be increased, greenhouse gases mitigated and resources recovered. All under a constant pressure on costs. The main objective of this research has been to develop a plant-wide modelling tool to evaluate the performance of operational strategies for multiple objectives at the plant and for off-site environmental impact.

    The plant-wide model platform Benchmark Simulation Model no. 2 (BSM2) has been modified to improve the evaluation of energy efficiency and include greenhouse gas emissions. Furthermore, the plant-wide process model has been coupled to a life cycle analysis (LCA) model for evaluation of global environmental impact. For energy evaluation, a dynamic aeration system model has been adapted and implemented. The aeration model includes oxygen transfer efficiency, dynamic pressure in the distribution system and non-linear behaviour of blower performance. To allow for modelling of energy recovery via anaerobic co-digestion the digestion model of BSM2 was updated with a flexible co-digestion model allowing for dynamic co-substrate feeds. A feasible procedure for substrate characterisation was proposed. Emissions of the greenhouse gases CO2, CH4 and N2O were considered. The bioprocess model in BSM2 was updated with two-step nitrification, four-step denitrification and nitrifier denitrification to capture N2O production. Fugitive emissions of the three gases were included from digestion, cogeneration and sludge storage. The models were tested in case studies for the three areas of development: aeration, co-digestion and greenhouse gas production. They failed to reject the hypothesis that dynamic process models are required to assess the highly variable operations of wastewater treatment plants. All parts were combined in a case study of the Käppala WWTP in Lidingö, Sweden, for comparison of operational strategies and evaluation of stricter effluent constraints. The averaged model outputs were exported to an LCA model to include off-site production of input goods and impact of discharged residues and wastes. The results reveal trade-offs between water quality, energy efficiency, greenhouse gas emissions and abiotic depletion of elemental and fossil resources.

    The developed tool is generally applicable for WWTPs and the simulation results from this type of combined models create a good basis for decision support.

  • 145.
    Arnell, Magnus
    et al.
    RISE Research Institutes of Sweden, Built Environment, System Transition and Service Innovation. Lund University, Sweden.
    Ahlström, Marcus
    RISE Research Institutes of Sweden, Built Environment, System Transition and Service Innovation.
    Wärff, Christoffer
    RISE Research Institutes of Sweden, Built Environment, System Transition and Service Innovation. Lund University, Sweden.
    Saagi, Ramesh
    Lund University, Sweden.
    Jeppsson, Ulf
    Lund University, Sweden.
    Plant-wide modelling and analysis of WWTP temperature dynamics for sustainable heat recovery from wastewater2021In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 84, no 4, p. 1023-1036Article in journal (Refereed)
    Abstract [en]

    Wastewater heat recovery upstream of wastewater treatment plants (WWTP) poses a risk to treatment performance, i.e. the biological processes. In order to perform a sustainability analysis, a detailed prediction of the temperature dynamics over the WWTP is needed. A comprehensive set of heat balance equations was included in a plant-wide process model and validated for the WWTP in Linköping, Sweden, to predict temperature variations over the whole year in a temperate climate. A detailed model for the excess heat generation of biological processes was developed. The annual average temperature change from influent to effluent was 0.78°C with clear seasonal variations, wherein 45% of the temperature change arose from processes other than the activated sludge unit. To address this, plant-wide energy modelling was necessary to predict in-tank temperature in the biological treatment steps. The energy processes with the largest energy gains were solar radiation and biological processes, while the largest losses were from conduction, convection, and atmospheric radiation. Tanks with large surface areas showed a significant impact on the heat balance regardless of biological processes. Simulating a 3°C lower influent temperature, the temperature in the activated sludge unit dropped by 2.8°C, which had a negative impact on nitrogen removal

  • 146.
    Arnell, Magnus
    et al.
    RISE - Research Institutes of Sweden (2017-2019). Lund University, Sweden.
    Astals, Sergi
    University of Queensland, Australia.
    Åmand, Linda
    IVL Swedish Environmental Research Institute, Sweden.
    Batstone, Damien J.
    University of Queensland, Australia.
    Jensen, Paul D.
    University of Queensland, Australia.
    Jeppsson, Ulf
    Lund University, Sweden.
    Modelling anaerobic co-digestion in Benchmark Simulation Model No. 2:parameter estimation, substrate characterisation and plant-wide integration2016In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 98, p. 138-146Article in journal (Refereed)
    Abstract [en]

    Anaerobic co-digestion is an emerging practice at wastewater treatment plants (WWTPs) to improve the energy balance and integrate waste management. Modelling of co-digestion in a plant-wide WWTP model is a powerful tool to assess the impact of co-substrate selection and dose strategy on digester performance and plant-wide effects. A feasible procedure to characterise and fractionate co-substrates COD for the Benchmark Simulation Model No. 2 (BSM2) was developed. This procedure is also applicable for the Anaerobic Digestion Model No. 1 (ADM1). Long chain fatty acid inhibition was included in the ADM1 model to allow for realistic modelling of lipid rich co-substrates. Sensitivity analysis revealed that, apart from the biodegradable fraction of COD, protein and lipid fractions are the most important fractions for methane production and digester stability, with at least two major failure modes identi fied through principal component analysis (PCA). The model and procedure were tested on bio-methane potential (BMP) tests on three substrates, each rich on carbohydrates, proteins or lipids with good predictive capability in all three cases. This model was then applied to a plant-wide simulation study which confirmed the positive effects of co-digestion on methane production and total operational cost. Simulations also revealed the importance of limiting the protein load to the anaerobic digester to avoid ammonia inhibition in the digester and overloading of the nitrogen removal processes in the water train. In contrast, the digester can treat relatively high loads of lipid rich substrates without prolonged disturbances.

  • 147.
    Arnell, Magnus
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Bygg och Mekanik, Urban Water Management. Lund University, Sweden.
    Astals, Sergi
    University of Queensland, Australia.
    Åmand, Linda
    IVL Swedish Environmental Research Institute, Sweden.
    Batstone, Damien
    University of Queensland, Australia.
    Jensen, Paul
    University of Queensland, Australia.
    Jeppsson, Ulf
    Lund University, Sweden.
    Substrate fractionation for modelling of anaerobic co-digestion with a plant-wide perspective2016In: 5th IWA/WEF Wastewater Treatment Modelling Seminar (WWTmod2016), 2016Conference paper (Refereed)
  • 148.
    Arnell, Magnus
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Hållbar Samhällsbyggnad. Lund University, Sweden.
    Jeppsson, Ulf
    Lund University, Sweden.
    Aeration system modelling - case studies from three full-scale wastewater treatment plants2015In: 9th IWA Symposium on Systems Analysis and Integrated Assessment (Watermatex 2015), 2015, article id 10.4Conference paper (Refereed)
    Abstract [en]

    The water train of three WWTPs have been modelled following the procedures of the Benchmark Simulation Model (BSM) platform (Gernaey et al., 2014). Additionally the aeration system has been modelled to evaluate airflows and energy performance. The results for the airflow model are presented. The chosen airflow model is shown to be easy to apply and calibrate and robust for practical modelling cases. By simply adjusting the SOTE-polynomial, number of diffusors and airflow limitations the model replicates the real data at a level of detail suitable for most purposes where the evaluation is based on longer time averages. For peak demand evaluation the whole treatment model with influent characterization, model calibration and controllers need to be more detailed than done here. Modelling the airflow is important to allow for evaluation of air consumption, aeration energy performance and for communication of simulation results to plant staff and operators.

  • 149.
    Arnell, Magnus
    et al.
    RISE - Research Institutes of Sweden, Built Environment, Energy and Circular Economy.
    Jeppsson, Ulf
    Lunds Universitet, Sweden.
    Rahmberg, Magnus
    IVL Swedish Environmental Research Institute, Sweden.
    Oliveira, Felipe
    IVL Swedish Environmental Research Institute, Sweden.
    Carlsson, Bengt
    Uppsala University, Sweden.
    Modellering av avloppsreningsverk för multikriteriebedömning av prestanda och miljöpåverkan2017Report (Other academic)
    Abstract [en]

    By using detailed dynamic plant-wide models and combining results from one-year simulations of ’within-the-fence’ WWTPs (both water- and sludge lines) with life-cycle analysis, different operational strategies can be developed and evaluated based on the total environmental impact (including external activities) while maximizing resource recovery and energy efficiency, maintaining good effluent quality and keeping track of the operational costs. The methodology has been applied and tested in an extensive case study of Käppala WWTP.

  • 150.
    Arnell, Magnus
    et al.
    RISE - Research Institutes of Sweden, Built Environment, Energy and Circular Economy. Lund university, Sweden.
    Lundin, Emma
    RISE - Research Institutes of Sweden, Built Environment, Energy and Circular Economy.
    Jeppsson, Ulf
    Lund university, Sweden.
    Sustainability Analysis forWastewater Heat Recovery - Literature Review2017Report (Other academic)
    Abstract [en]

    This technical report describes the literature review conducted on wastewater heat recovery (WWHR). As part of the urban water cycle, domestic hot water consumes the lion share – up to 90 % – of the total energy requirement for water management. Individual energy consumption of 780 to 1 150 kWh/cay/yr has been estimated in Sweden. Energy can be recovered from wastewater, in buildings close to the source or further downstream in the wastewater system. Depending on wastewater flow and temperature heat exchangers or heat pumps (or a combination of both) can be used for extracting heat the energy. Obstacles for utilizing this potential are for example: clogging and fouling of equipment, potentially negative system impacts and economic feasibility. Examples of various WWHR implementations have been found in Sweden, Switzerland and North America. Some installations have been running for a long time and technical function and financial viability has been evaluated and are reviewed in the report. Generally, heat pumps reach a coefficient of performance of 3 to 7, better the higher the wastewater temperature is, i.e. further up-stream.

    WWHR application in a wastewater system can be modelled. The domestic hot water requirement and associated energy use has been modelled previously and concepts can be adapted for modelling the larger system. Equations for calculating performance and output variables from heat recovery equipment have been reviewed and is presented. For the purpose of assessing single WWHR installations in sewers, detailed models have been developed and presented. There are reviewed in the text. Concepts for estimating temperature variations in sewers are essential to assess the impact on wastewater treatment plants. Performance of wastewater treatment plants and their temperature dependence can be modelled with existing process models. Temperature variations along the course of the treatment plant might be important to consider.

    In Sweden, there are currently some regulations related to WWHR. The temperature of hot water systems in buildings are regulated to prevent Legionella outbreaks. Furthermore, the practice of WWHR is limited in extent and requires a permit from the utility as by the contract between the consumer and the utility. Currently, this limits the implementation of WWHR in Sweden.

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