Treatment Of Brewery Wastewater Using Anaerobic Sequencing Batch Reactor (ASBR)

More attention on Anaerobic Sequencing Batch Reactor (ASBR) is paid because of its many advantages such as low investment, flexibility of the operation and the ability of enduring perturbation and so on. However no report is documented in engineering. There may be two main reasons. One is that there is pressure fluctuation in the ASBR because of the batch-fed and batch-decanted; the other is that the volatile fatty acid can accumulate in the ASBR because of the batch operation. In this paper, start-up and granulation in a pilot-scale ASBR with a floating cover fed with brewery wastewater were investigated.Sludge granulation proceeded after 60 days operation. The granular sludge formed has good settling ability and biomass activity can reach as high as 0.216gCOD-CH₄/gVSS·d , 0.825gCOD-CH₄/gVSS·d, 0.237gCOD-CH₄/gVSS·d and 0.796gCOD-CH₄/gVSS·d for formate, acetate, propionate and butyrate, respectively.Long time experiments showed that the reactor worked stably and effectively for COD removal. When the organic loading rate was controlled between 1.5kgCOD/m³.d -7.0kgCOD/m³.d, and hydraulic retention time one day, COD removal efficiency could reach more than 80%. COD in effluent is smaller than 300mg/L. When VFA in influent was between 300mg/L and 1500mg/L, COD remove efficiency was not affected significantly, Gas production rate was 0.41m / kgCOD. and methane content was between 50 to 70 percent. The sludge particle size was smaller than that raised in UASB, but the density is big. The mature particle size is about 1.5mm and VSS/SS reaches 91% and the settling rate is 45m/h. High specific methanogenic activity (SMA) for formate was observed. The study suggests that ASBR technology is a potential alternative for brewery wastewater treatment. perhaps the propionic acid and the butyric acid transforms through formic acid pathways as the Acetatic acid. when temperature climb to 65℃, the system brokedowm and could reconstruct, It is feasible to treat the high strength brewery waste water in the ASBR.