Novel Bioremediation Approach For Treatment of Naphthalene, Ammonia-N and Sulphate in Fed-batch Reactor

An anaerobic-anoxic-aerobic sequential fed batch reactor was adopted in this study for simultaneous biodegradation of naphthalene (NAP), ammonia-N (NH4+-N) and sulphate (SO42-). Influent NAP concentration (50-300 mg L-1) was varied with constant NH4+-N (50 mg L-1) and SO42- (250 mg L-1) at total HRT of 16 days. The corresponding influent chemical oxygen demand (COD) concentration was 230-1380 mg L-1. In anaerobic reactor, with an increase in NAP loading from 3.125 to 18.75 mg L-1 day(-1), 81.77% NAP removal occurred at 300 mg L-1 influent naphthalene concentration, whereas 43.47% COD removal was obtained at this concentration. Anoxic reactor also known as denitrification reactor was able to remove 59.04% nitrate and 70.21% COD at maximum NAP loading of 1.75 mg L-1 day(-1). Aerobic reactor conquered good removal efficiency with NAP (99%), COD (93.91%) and NH4+-N (94.44%). Kinetic results revealed that Grau second order model is more suitable as compared to that of Stover-Kincannon model for removal of substrates in the fed-batch reactor.