抄録
The inhibitory effects of 2-mercaptobenzothiazole (MBT), sulfur, stearic acid and Zn2+ contained in rubber thread wastewater on aceticlastic methanogens or nitrifyingbacteria were investigated. It was found that Zn2+ inhibited strongly the activity ofaceticlastic methanogens. After the pH of rubber thread wastewater was adjusted to 5, Zn2+ was removed to less than 5 mg l-1 by coagulation with addition of Na2S. After removal of Zn2+ in rubber thread wastewater, the TOC compounds and NH4+ were efficiently treated in anaerobic treatment followed by biological nitirification with recirculation. In this process, the TOC compounds and NO3- were simultaneously removed in the UAFP reactor. However, the TOC removal efficiency in the UAFP reactor decreased from 90% to 80% at the same TOC loading rate by recirculating the effluent from the nitirification reactor. Methane gas evolution rate also decreased proportionate to the decrease in the TOC removal efficiency. In addition, energy production of 19.5 kcal (l of rubber thread wastewater) -1 would be expected in the simultaneous treatment process.
