Biological Treatment of Recalcitrant Industrial Wastewater Using Microbial Augmentation and Bioflocculant-Producing Microorganisms

Abstract

For effective treatment of recalcitrant industrial wastewater, microbial augmentation J30, which is composed of Pseudomonas sp. GT21, Bacillus sp. KN27, Acinetobacter sp. KN11, and Neisseria sp. KN13, decomposing strains that show high activities on various organic substances and aromatic compounds, were prepared. As a method to control the solid suspension of industrial wastewater, the culture solutions of A and B, which produce bioflocculants, were applied to wastewater treatment. A microbial augmentation for treating laundry wastewater containing TCE and PCE were prepared by mixing 4 types of strains used to treat paper mill wastewater, 6 types of strains prepared by formulating culture solutions of Flavobacterium sp. GN18 and Acalgenes sp. GN23, which are richloroethylene and pentachloroethylene decomposing strains. It was named microbial augmentation TP32. These culture solutions of strain groups were added to treat paper mill wastewater containing phenolic chlorine compounds and laundry wastewater containing chlorine compounds efficiently. The removal efficiencies of the treatment groups, for TOC in paper mill wastewater were 81.9 % and 73.2 %, respectively. The TOC removal efficiency in paper mill wastewater was 86.5 % in the mixed strains treatment group, where decomposing and flocculating strains were added simultaneously. Changes in T-N and T-P showed a removal efficiency of more than 70 % in all treatments using decomposing, flocculating, and mixed strains. Still, the mixed strain treatment showed the highest removal efficiency. The phenolic chlorine compound, 3-chlorophenol removal efficiency was 85.1 % in the mixed strain treatment group. The removal efficiency of TCE from laundry wastewater showed a removal rate of 85.3 % in 42 hours of incubation when only decomposing strains were added and a removal rate of more than 90 % in 32 hours of incubation when mixed strains were added. The PCE removal rate has been decreased over time of incubation in the decomposing strain treatment and mixed strain treatment, respectively.