Anaerobic biodegradability of 3, 4, 5-trimethoxybenzaldehyde manufacturing wastewater and anaerobic treatment using UASB reactor

In this study, with the aim of finding an economic and effective option for treating 3, 4, 5-trimethoxybenzaldehyde manufacturing wastewater from a chemical industries, Ltd., the anaerobic biodegradability of the wastewater was evaluated by a series of batch experiments. Based on the experimental data, the anaerobic treatment of the wastewater was investigated, using a single UASB, with activated sludge as seeding sludge. The influence of the organic loading rate(OLR) on the performance of the reactor was evaluated, from an initial 1.0 g·(L·d)^-1 to a maximum of 10.0 g ·(L·d)^-1, by step-increasing the influent COD with unaltered HRT. During 140 days of continuous operation, it was observed that the optimal OLR was 6.0 g·(L·d)^-1 when the influent COD was approximately 6 000 mg·L^-1, corresponding to a 60.3% COD removal rate. The respective values of pH and VFA in the effluent were approximately 7.4 and 500 mg·L^-1. The experimental data during the long-term experimental run indicated the feasibility of UASB for treating of 3, 4, 5-trimethoxybenzaldehyde manufacturing wastewater.