Yellow ginger processing wastewater treatment by a hybrid biological process

With a hybrid wastewater treatment process consisting of neutralization, precipitation, modified two-phase anaerobic digestion, and biological aerated filter (BAF) being developed, the yellow ginger processing wastewater with high COD and high sulphate was treated successfully in the laboratory. With an inserted stripping unit, the modified two-phase anaerobic digestion process eliminated the inhibition of methanogens to the greatest extent, which results in a high-efficiency COD removal. Subsequently, the effluent from the anaerobic units was treated with excellent results in the novel BAF which was equipped with special carriers. This was due to the simultaneous nitrification and denitrification (SND) that occurred there. When the raw water with COD of 18,000-20,000 mg/L, SO42- of 8,500-11,000 mg/L, and NH4+-N of 220-300 mg/L was treated by the hybrid process, the concentrations of COD, NH4+-N, and total nitrogen (TN) in the effluent were lower than 100, 10 and 15 mg/L, respectively. (c) 2008 Elsevier Ltd. All rights reserved.