|
|
||||||||
a Dep. of Civil, Geological, and Mining Engineering, École Polytechnique de Montréal, Montreal, QC, Canada H3C 3A7
b Dep. of Applied Sciences, Univ. du Québec en Abitibi-Témiscamingue, Rouyn-Noranda, QC, Canada J9X 5E4
* Corresponding author (gerald.zagury{at}polymtl.ca)
Received for publication February 15, 2006. Acid mine drainage (AMD), characterized by low pH and high concentrations of sulfate and heavy metals, is an important and widespread environmental problem related to the mining industry. Sulfate-reducing passive bioreactors have received much attention lately as promising biotechnologies for AMD treatment. They offer advantages such as high metal removal at low pH, stable sludge, very low operation costs, and minimal energy consumption. Sulfide precipitation is the desired mechanism of contaminant removal; however, many mechanisms including adsorption and precipitation of metal carbonates and hydroxides occur in passive bioreactors. The efficiency of sulfate-reducing passive bioreactors is sometimes limited because they rely on the activity of an anaerobic microflora [including sulfate-reducing bacteria (SRB)] which is controlled primarily by the reactive mixture composition. The most important mixture component is the organic carbon source. The performance of field bioreactors can also be limited by AMD load and metal toxicity. Several studies conducted to find the best mixture of natural organic substrates for SRB are reviewed. Moreover, critical parameters for design and long-term operation are discussed. Additional work needs to be done to properly assess the long-term efficiency of reactive mixtures and the metal removal mechanisms. Furthermore, metal speciation and ecotoxicological assessment of treated effluent from on-site passive bioreactors have yet to be performed.
Abbreviations: AMD, acid mine drainage SRB, sulfate-reducing bacteria DOM, dissolved organic matter COD, chemical oxygen demand HRT, hydraulic retention time PRB, permeable reactive barrier HRC, hydrogen release compounds
This article has been cited by other articles:
![]() |
J. Eriksen, P. Sorensen, and L. Elsgaard The Fate of Sulfate in Acidified Pig Slurry during Storage and Following Application to Cropped Soil J. Environ. Qual., January 4, 2008; 37(1): 280 - 286. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Vadose Zone Journal | Journal of Plant Registrations | ||||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal |