磷化氢生物净化体系的微生物特性及过程强化

生物法净化低浓度磷化氢尾气的有效性已经得到验证，但磷化氢降解功能微生物理化特性、磷化氢难溶于水的特性如何影响其生物转化效果鲜有报道。本研究从磷化氢长期驯化的活性污泥体系中分离纯化出对磷化氢有耐性或降解作用的单一菌株，并对典型菌株利用碳源与磷源、磷化氢生物净化过程强化进行比较。结果表明：分离得到的M4、M5菌株分别与寡养单胞菌属（Stenotrophomonas）、片球菌属（Pediococcus）具有极高的相似度，其增殖培养形成的活性污泥体系以乳酸钠为碳源时，最大的磷化氢净化率分别高达28.9%与37.9%；吸收液中添加正磷酸盐，可适当提升磷化氢生物净化效果。当生物体系中添加椰壳基炭材料时，磷化氢更容易从气相转入液相吸收液中，耦合体系中磷化氢吸收速率达到0.0552mg/(m²·s)，去除率提升至67.3%。采用活性污泥体系净化磷化氢时，次磷酸盐是其生物氧化的必然产物，之后进一步氧化成其他高价含磷化合物；进口混合气中的磷化氢从气相转入吸收体系后，除导致液相中磷浓度上升外，大部分磷将以化合物形式储存至微生物体内。

Microbial characteristics and process enhancement of phosphine bio-purification system

The effectiveness of bio-purifying technology for low concentration phosphine has been verified, however many aspects have seldom been reported, such as what is the physicochemical properties of PH₃-degrading microbes and how the water-insoluble property of phosphine affects its bioconversion. In this study, some kinds of microbes with the characteristics of PH₃ tolerance or degradation were isolated and purified from activated sludge system operated for a long time, and comparative experiments were conducted on the physicochemical characteristics of typical strains and process enhancement of phosphine bio-purification system. The strains of M4 and M5 were highly similar to Stenotrophomonas and Pediococcus, respectively. When sodium lactate was used as carbon source for the activated sludge systems formed by the proliferation of M4 and M5 strains, the corresponding PH₃ removal rates were up to 28.9% and 37.9%, respectively. The addition of orthophosphate in absorption solution can moderately improve the effect of phosphine bio-purification. As coconut shell-based carbon was added to the bio-purification system, phosphine might be easily transferred from gas phase to absorption liquid, and the PH₃ absorption rate in the synergetic system was 0.0552mg/(m²·s) with the removal rate increasing to 67.3%. As activated sludge system was adopted to purify the PH₃ offgas, hypophosphate was the inevitable product of PH₃ biological oxidation, which might be further oxidized into other high-valent phosphorous compounds. After PH₃ entered the absorption system, it resulted in the increase of phosphorus in the absorption liquid, and most of the converted phosphorus might be stored as compounds in microorganisms.