title: Acetate and ethanol as potential enhancers of low temperature denitrification in soil contaminated by fur farms: a pilot-scale study.
abstract: Ethanol and acetate were examined as potential candidates to enhance denitrification at low temperature in soils contaminated by fur farms. Five pilot-scale sand and gravel columns with a top layer of soil from a fur farm were set up and fed with nitrate-containing water (influent concentration of 100 and 200 mg L(-1)) for 459 days at 6+/-2 degrees C. Two of the columns also received acetate and two other ethanol while one received no additional C-substrate. During the experiment, various C:N-ratios were tested to find the most optimal concentration of the added C-substrates, and effluent concentrations of nitrate, nitrite, and TOC were monitored. At the end of the experiments, soils in the columns were unpacked and the soils were used to measure a pattern of enzyme activities and the rates of denitrification in microcosms. The fur farm contaminated soil appeared to harbour a good intrinsic potential for denitrification, which could be greatly enhanced by the introduction of ethanol or acetate. Consequently, in the C-substrate-fed columns, 95-100% of the influent nitrate was removed after an acclimatization period of some weeks. Ethanol with C:N-ratio of ca. 6 at the nitrate level 200 mg L(-1) proved to be the most promising candidate to be used in field trials.
authors.affiliation: Finnish Environment Institute, P.O. Box 140, FI-00251 Helsinki, Finland.
authors.forename: Derek
authors.initials: D
authors.lastname: Martin
authors.forename: Jani M
authors.initials: JM
authors.lastname: Salminen
authors.forename: R Maarit
authors.initials: RM
authors.lastname: Niemi
authors.forename: Ilse M
authors.initials: IM
authors.lastname: Heiskanen
authors.forename: Matti J
authors.initials: MJ
authors.lastname: Valve
authors.forename: Pasi P
authors.initials: PP
authors.lastname: Hellstén
authors.forename: Taina H
authors.initials: TH
authors.lastname: Nystén
mesh_terms: D000085:Acetates / Q000737:chemistry; D000818:Animals; D000829:Animals, Domestic; D003080:Cold Temperature; D000431:Ethanol / Q000737:chemistry; D009566:Nitrates / Q000302:isolation & purification*; D009573:Nitrites / Q000302:isolation & purification; D012989:Soil Pollutants / Q000302:isolation & purification*
chemical_list: D000085:Acetates; D009566:Nitrates; D009573:Nitrites; D012989:Soil Pollutants; D000431:Ethanol