Anaerobic Treatment of Textile Wastewater using EGSB

In this study expanded granular sludge bed (EGSB) reactor has been used to investigate the removal efficiency of chemical oxygen demand (COD), and color of textile wastewater. Synthetic Textile wastewater was treated in an EGSB reactor seeded with non granular anaerobic sludge from UASB reactor treating sugar mill wastewater of Badagandi sugar mill at Badagandi village, Bagalkot district, Karnataka, India and active septic tank. The initial volatile suspended solid concentration was 20.40 g/L. The study was carried out at ambient temperature 29�ºC to 37�ºC in the laboratory scale reactors of 8.4 L effective volume. Reactor was fed with macro and micro nutrients. Successful reactor startup with granulation was achieved within 13 days of operation using Chitosan as polymer. During startup the hydraulic retention times (HRT) was kept constant for 12 hrs. A maximum COD removal efficiency of 89.95% was achieved at organic loading rate (OLR) of about 8 KgCOD/m3/d. And the maximum bio gas production was 20.4 l/d. During operation period synthetic textile wastewater was fed step by step with increasing concentration of 25%, 50% and 75% of influent COD (5000 mg/L) respectively. Loading was increased by reducing HRT to 6 hrs, 3 hrs, 1.5 hrs and 1 hr respectively. Results indicated that anaerobic treatment of textile wastewater was possible with the supplementation of an external carbon source in the form of glucose (600mg/L). The corresponding maximum COD and color removals were 78.4% and 69% respectively for HRT of 1.5 hrs and OLR of 80 Kg COD/m3/d at ambient temperature.