高pH条件下UASB反应器处理含硫酸盐废水的性能

利用升流式厌氧活性污泥床(UASB)反应器处理高含硫有机废水,考察了其在pH=8.5条件下的运行性能、MPA(产甲烷菌)与SRB(硫酸盐还原菌)的竞争规律及微生物群落结构特征.结果表明:在pH=8.5的厌氧生物处理系统中,COD的去除率达到70％以上和硫酸盐去除量达到1 600 mg?L-1,在整个运行期间均保持较好的...

Performance of UASB system on treating sulphate containing wastewater under high pH condition

A laboratory-scale up-flow anaerobic sludge blanket (UASB) was used and consciously operated at the high pH of 8.5 to investigate the removal performance on high sulfur organic wastewater in terms of the competitive rule between methane producing archaea (MPA) and sulfate-reducing bacteria (SRB) and the structure characteristics of microbial community. The results showed that UASB had a COD removal rate over 70% and sulfate removal of about 1600 mg·L−1 when the system was operated at the pH = 8.5, which maintained a good performance during the operation. Although the ratio of COD to ${rm{SO}}_4^{2 - }$ (i.e., COD/${rm{SO}}_4^{2 - }$) was an important impact factor on the reactor performance, the MPA was still a dominant bacteria when COD/${rm{SO}}_4^{2 - }$ widely fluctuated from 1 to 10. At the whole operating stage, the concentration of free H2S in aqueous was lower than 5.7 mg·L−1, and the concentration of H2S in biogas was at a low level (≤1.5 mg·L−1). The three main alkali-resistance MPAs were identified as Methanosaeta sp., Methanobrevibacter and unclassified_f_Methanobacteriacea, respectively. Thus, high pH could contribute to take away the toxicity inhibition of free H2S on MPA activity, and also reduce the content of H2S in biogas, which can provide reference for high pH anaerobic treatment of sulfuric acid wastewater.