Pollution Research Paper

BIO-HYDROGEN AND BIO-METHANE PRODUCTION FROM DISTILLERY WASTEWATER IN BI-PHASIC ASBR

K. AKIV AND S. JAYANTHI

Abstract

Distilleries are one of the most polluting industries generating large volumes of carbohydrate rich wastewater. Studies were made to investigate the potential of bio-hydrogen production and bio-methane production from distillery wastewater using two-phase system comprising of two separate anaerobic sequencing batch reactors in series. The active volume of both the reactors was 3.5L. Pretreated anaerobic distillery sludge and anaerobic distillery sludge were used as seed in hydrogen reactor and methane reactor respectively. Rio-hydrogen production was studied by dark fermentation process at ambient temperature and operating pH of 6.0*0.2. The hydrogen reactor was sequenced three times a day providing a cycle length of 8h and the methane reactor was sequence once a day with a cycle length of 24h. Each cycle of operation consisted of four stages: feed, react, settle and decant. The organic loading rate was increased by decreasing the hydraulic retention time from 96h to 72h, 48h, 36h and 24h. Gas production trend and cumulative gas production were studied at various hydraulic retention times. Maximum gas production was observed at 36h HRT in the hydrogen reactor and 29h HRT in the methane reactor. Experimental data recorded a maximum volumetric gas production rate of 1.286m3/m3/d at 48h HRT in the hydrogen reactor and 0.577mi/ms/d at 96h HRT in the methane reactor. Maximum specific gas production was observed to be 0.07976mailcgc0o in the hydrogen reactor and 0.02967m'/kg, , in the methane reactor. Substrate degradation rate was found to vary from 8.89kg0odms/d at OLR of 22.99kg0,/mgcl to 10.07kgcolinsid at OLR of 91.971cgcm/m3/d in the hydrogen reactor and from 4.8625kgc0imgd at OLR of 14.1kgc„ine/d to 21.4kgc0ints/d at OLR of 81.9kgmdmqd in the methane reactor. Experimental data showed the feasibility of bio-hydrogen and bio-methane production with substrate degradation using distillery wastewater as substrate.