Change search
ReferencesLink to record
Permanent link

Direct link
Social, Economical and Technical Evaluation of a reverse osmosis drinking water plant in the Stockholm Archipelago
KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
2007 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

The drinking water plant in this case study is a combined groundwater and reverse osmosisplant in the Stockholm archipelago. The reverse osmosis purification step was added to theplant in 1995. This technique is relatively new in Sweden and there are possibilities for it tobecome a good complement to conventional drinking water treatment. The plant has used thistechnique for over 10 years with good results. It is therefore of great interest to evaluate anddocument it for the possibility to implement this technique in areas not connected toconventional drinking water production.Reverse osmosis separates the incoming water to a clean permeate and concentrate ofremoved particles, larger molecules and ions. This technique has a high purification degree. Itcan remove dissolved particles and microorganisms without disinfection. However, it isrelatively expensive due to a high electricity consumption compared to conventional drinkingwater treatment. The high electricity consumption in this kind of system depends on aphenomenon called membrane fouling caused by the constituents in the raw water, graduallybecoming enriched on the membrane surface.The aim of this thesis was to evaluate and document a drinking water plant in the Stockholmarchipelago from a social, economical, technical and environmental perspective. A socialsurvey in the form of a questionnaire was conducted to reveal opinions about the water qualityprovided by the plant. The economical evaluation was done to estimate the cost of drinkingwater production and find the water cost in Kr/m3. The technical part involved documentationof the plant layout and evaluation of its performance. To assess the performance historicalchemical and microbial analyses were evaluated. A mass balance was attempted to drawconclusions for the overall system. The environmental part of the plant assessment, includedan estimate of the electricity and chemicals use in the plant.The results revealed that from an overall perspective the water quality from the plant issatisfactory with some concerns about metal taste and turbidity that sometimes occur. Thepotential presence of dangerous algal toxins in the water was also a concern. The totalproduction cost in Kr/m3 is higher than expected and higher than sales price. In technicalterms, the plant has functioned well. However, there is a need to monitor more parameters inthe plant including; more flow parameters, concentrations of added chemicals and more waterquality parameters. Electricity consumption has been higher than expected. Control(throttling) valves in the brine reject are relatively large energy consumers and arecommendation is to investigate potential savings by changing them for pressure exchangevalves.

Place, publisher, year, edition, pages
2007. , 120 p.
Trita-IM, ISSN 1402-7615 ; 2007:36
Keyword [en]
Reverse osmosis, desalination, brackish seawater, groundwater, drinking water
National Category
Social Sciences Interdisciplinary
URN: urn:nbn:se:kth:diva-32777OAI: diva2:411861
www.ima.kth.seAvailable from: 2011-05-02 Created: 2011-04-19 Last updated: 2011-05-02Bibliographically approved

Open Access in DiVA

fulltext(1905 kB)1802 downloads
File information
File name FULLTEXT01.pdfFile size 1905 kBChecksum SHA-512
Type fulltextMimetype application/pdf

By organisation
Industrial Ecology
Social Sciences Interdisciplinary

Search outside of DiVA

GoogleGoogle Scholar
Total: 1802 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 326 hits
ReferencesLink to record
Permanent link

Direct link