Pilot-scale barrier system for removal of nitrate in mine drainage
2011 (English)In: Mineralogical magazine, ISSN 0026-461X, E-ISSN 1471-8022, Vol. 75, 1012-1012 p.Article in journal (Other academic) Published
Undetonated ammonium nitrate is readily soluble in water and quickly enters into the mine water and process water at amine site. In order to investigate the application of nitrate removal by denitrification in the cold climate of northern Sweden, a pilot-scale barrier system was constructed of sheet metal in autumn 2009 at the Malmberget iron ore mine.
The barrier (9m x 2m x 1.5m) appears as an open basin with three inner dividing walls, and is filled with a reactive mixture consisting of crushed rock, sawdust, and sewage sludge. Water flows through the barrier at ca. 0.45 m3/hour.The chemical analyses of water flowing into and out of thebarrier during 2010 indicate that the degree of nitrate removal generally lay in the range between 11 and 77% of influent nitrate concentrations. Stable isotope analyses of δ15N and δ18O in nitrate demonstrate an enrichment in 15N and 18O in nitrate as water flows through the barrier, supporting theconclusion that denitrification is responsible for nitrateremoval. Ammonium concentrations in the barrier effluents are initially high, but these high levels are subsequently flushed from the barrier.
In order to increase the degree of nitrate removal by denitrification in the barrier, a reactive carbon source needs to be added to the influent waters; this will be tested during the 2011 field season.
Place, publisher, year, edition, pages
2011. Vol. 75, 1012-1012 p.
IdentifiersURN: urn:nbn:se:uu:diva-165209OAI: oai:DiVA.org:uu-165209DiVA: diva2:472454