Bioremediation of pendimethalin contaminated soil by augmented bioslurry phase reactor operated in sequential batch (SBR) mode: Effect of substrate concentration

Bioslurry phase reactor augmented with ETP microflora was studied for the degradation of pendimethalin contaminated soil. The effect of substrate concentration on the process performance was evaluated in the slurry phase reactor operated in sequence batch mode under anoxic-aerobic-anoxic microenvironment with a total cycle period of 120 h. The performance of augmented slurry phase system was found to be effective among the studied experiments. The degradation of the substrate in slurry system was found to be governed by the substrate loading rate. The system performance was sustained upto 5000 μg/g of substrate loading. Increase of concentration above 7,500 μg/g resulted in process inhibition. The degradation of pendimethalin in slurry phase system was found to be compared to the degradation in the soil phase. The half-life of pendimethalin in slurry phase system was found to be about 40 h which was quite rapid compared to the rate of degradation in the soil phase. The augmented slurry phase system coupled with sequential batch mode operation appears to have resulted in effective performance at higher substrate concentration.