高硫酸盐难降解废水高温厌氧处理中限量曝气的应用及影响

由于硫酸盐还原的影响,普通高温UASB反应器处理亚硫酸盐纸浆厂排出的高硫酸盐难降解废水过程中甲烷菌活性受到了严重抑制.考虑到空气对硫化氢的吹脱和对硫化物的氧化作用可能减轻硫化物对甲烷菌的抑制,本研究在厌氧反应器中引入限量曝气措施.试验结果表明,反应器的运行稳定性和处理能力均得到大幅提高.在有机负荷提高到原来2倍的情况下,曝气后COD去除率仍有提高,从40%～50%提高到60%～70%.试验证明部分甲烷菌可以耐氧,而某些种类的水解酸化细菌则对不完全厌氧环境比较敏感.

Effect of Limited Aeration on the Thermophilic Anaerobic Treatment of High-Sulfate Refractory Wastewater

A thermophilic up-flow anaerobic sludge blanket (UASB) reactor was used to treat high-sulfate refractory wastewater from a sulfite pulp mill. The microorganisms were inhibited significantly as the result of sulfate reduction. Based on the consideration that the limited aeration may strip hydrogen sulfide out and oxidize part of the sulfide into nontoxic elemental sulfur, limited aeration was introduced into the reactor later to reduce the inhibition. The reactor showed much better running stability and higher treatment capacity thereafter. COD removal increased from 40%~50% to 60%~70% when the organic loading rate (OLR) was doubled. This study verified that some methanogens could be aerotolerant while some of the fermentation bacteria might be sensitive to the incomplete anaerobic surroundings.