Conductivity measurements for controlling municipal waste-water treatment
2010 (English)In: Research and application of new technologies in wastewater treatment and municipal solid waste disposal in Ukraine, Sweden and Poland: Proceedings of a Polish-Swedish-Ukrainian seminar / [ed] E. Plaza, E. Levlin, 2010, 51-62 p.Conference paper (Other academic)
Conductivity measurements can be used to monitor the processes in wastewatertreatment that causes changes in conductivity. The processes that in many treatment plants causechanges in conductivity are mainly biological nitrogen removal. Conductivity measurements fromtwo WWTP in Stockholm show no reduction of conductivity in the presedimentation and 21 and28% reduction in the activated sludge process. The conductivity in the inflowing wastewater toLotsbroverket WWTP in Mariehamn, Åland, during 2006 varies from 58 mS/m to 137 mS/m withabout 23% reduction of conductivity in the activated sludge process. At Duvbacken WWTP inGävle, which have biological phosphorus removal and no nitrogen removal, the conductivityvaried between 60 and 100 mS/m with no difference between influent and effluent. Biological Premovalwill give a reduction with 344 to 278 μSm2/g P. However, since the contribution ofphosphate ions can be calculated to about 1 % of measured conductivity phosphorus removal willnot give any decrease in conductivity. Since ammonium nitrogen and alkalinity, which is reducedat biological nitrogen removal, contributes to conductivity with about 33 % and 14 % respectively,it is the three WWTP with biological nitrogen removal that has a decrease in conductivity in thetreatment process. At chemical phosphorus precipitation phosphate will substituted with sulfateand no reduction in conductivity will be achieved. Reduction of conductivity due to biologicalnitrogen removal will consume alkalinity or hydroxide ions. If the amount of available alkalinity ishigh enough (one mole alkalinity per mole ammonia) biological N-removal through nitrificationfollowed by denitrification will give a decrease of conductivity with 842 μSm2/g N. Separationprocesses such as removal of suspended solids through sedimentation or filtration will give nochanges ion conductivity. Separation of nutrients through reverse osmosis will give large changesin conductivity and conductivity can thus be used for controlling the process.
Place, publisher, year, edition, pages
2010. 51-62 p.
, Joint Polish - Swedish reports, ISSN 1650-8610 ; 15
Conductivity, Wastewater treatment, Phosphate, Nitrate, Biological nutrient removal
IdentifiersURN: urn:nbn:se:kth:diva-81566ISBN: 978-91-7415-412-2OAI: oai:DiVA.org:kth-81566DiVA: diva2:497628
Polish-Swedish-Ukrainian seminar, Ustron, Poland, November 23 – 24, 2007
QC 201204192012-02-102012-02-102012-04-19Bibliographically approved