Effect of Linoleic Acid and COD/SO42- Ratio on Anaerobic Sulphate Reduction in Semi-Continuous Reactors
Anaerobic sulphate reduction method has the potential for being effective and economically viable over conventional treatment methods for the treatment of sulphate rich wastewater such as acid mine drainage (AMD). However, a major challenge in anaerobic sulphate reduction is the diversion of a fraction of organic carbon towards methane production. Use of long chain fatty acids (LCFA) as a methanogenic inhibitor to enhance sulphate reduction has the potential for being economically attractive since it is easily available at low cost. The present study investigated the effect of linoleic acid (LA) and COD/SO42- ratio on anaerobic dissimilatory sulphate reduction in semi continuous suspended growth system at 37 oC. Without LA, sulphate reduction of 50% was observed at a COD/SO42- ratio of 0.75. Sulphate reduction increased with increasing LA concentrations and at 1000 mg/L, almost 100% sulphate reduction was achieved.