Reactive barrier system for nitrate removal from mine effluents in northern Sweden: Laboratory experiments
2010 (English)In: Geophysical Research Abstracts, Vol. 12, EGU2010-4177, 2010, 4177- p.Conference paper (Other academic)
Laboratory column experiments have been conducted to determine nitrate removal rates from mine effluents bydenitrification, with the purpose of providing initial data for the construction of a pilot scale reactive barrier systemat the Malmberget iron mine, Sweden. Experiments were conducted at several different flow rates at 5C, 10C androom temperature; annual mean temperatures at the Malmberget site lie close to 0C. Columns were filled with anorganic substrate consisting of sawdust mixed with sewage sludge, the source of denitrifying bacteria, supportedby oven-dried clay pellets. Apparent denitrification rates, calculated from inflow and outflow nitrate concentrationsand column hydraulic residence time, ranged from 5 to 13 mg N/L/d, with the lowest rates corresponding to the 5C experiments. These rates are, however, limited to a certain degree by the low flow rate and the supply of electronsacceptors (i.e. nitrate) to denitrifying bacteria.
Results from the column experiment have been used to construct a barrier system in Malmberget, Sweden.Trial runs with the pilot-scale barrier will be conducted during 2010, with the purpose of determining the performanceof the barrier as mean air temperatures increase from below to above 0C and saturated flow commences inthe barrier. The barrier system is constructed as a rectangular container with steel sheet walls (9m length in flowdirection, 1.5m deep), and the flow rate will be adjusted to a hydraulic residence time of 1 day. The pilot-scalebarrier system currently lies above ground, but a permanent barrier system would be installed
Place, publisher, year, edition, pages
2010. 4177- p.
, Geophysical Research Abstracts, 12
Earth and Related Environmental Sciences
IdentifiersURN: urn:nbn:se:uu:diva-138442OAI: oai:DiVA.org:uu-138442DiVA: diva2:379184
EGU General Assembly 2010, 2-7 May, 2010 in Vienna, Austria