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Updated: Feb 8, 2026

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Effect of COD/SO(4)(2-) ratio and alkalinity on COD removal and sulfate reduction in two-phase expanded granular
Abstract:
In the present study, a bench-scale two-phase expanded granular sludge bed (EGSB) reactor was applied for treatment of high-sulfate wastewater. The reactor was operated continuously at 35°C. The EGSB 1, as sulfate-reducing phase, and EGSB2, as methane-producing phase, were combined after successful start-up. The treatment characteristics, including the effect of influent COD/SO(4)(2-) ratio and alkalinity in reactor have been discussed for EGSB1 and EGSB2 respectively. When total COD removal was 85%, the influent COD/S0(4)(2-) ratio was 2.8. When the ratio was less than 2.8, the COD removal descended quickly. The total sulfate removal then raised to 90% and the ratio exceeded 4.4. When influent alkalinity was kept at 8-10 mmol l(-1), the total COD and SO(4)(2-)removal reached 93.3% and 94.0% respectively. The results presented in the study provide some useful information for optimization of COD removal and SO(4)(2-) reduction process in wastewater treatment.
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