为解决消化液回用带来的氨氮累积问题，寻求关键控制参数，在序批式水解UASB两相厌氧消化体系中对有机垃圾中各种氮素转化特性进行了试验研究；基于上述研究分析结果建立了消化液回用时有机垃圾两相厌氧消化氨氮累积模型，找出了消化液回用中氨氮累积的关键控制参数——回流比；并通过试验验证了当回流比为0.85时，系统内UASB出水氨氮浓度最终趋于一定值，约为1 900 mg/L；此氨氮浓度并未对产甲烷反应器产生负面影响，反而提高了系统对酸碱的缓冲能力，保证了系统的稳定运行；从而为有效预防厌氧消化中“氨抑制”问题提供技术参考。

Nitrogen transformation characteristic experiments of organic fraction of municipal solid waste (OFMSW) in a batch hydrolysis-UASB two-phase anaerobic digestion are carried out to solve the problems of total ammonia-nitrogen (TAN) accumulation and obtain appropriate key process control parameters. Based on the experiment results, TAN accumulation prediction model in the two-phase anaerobic digestion of OFMSW with digestive effluent reuse is established. And then with the prediction model analyzed, reflux ratio is obtained as a key process control parameter to prevent TAN accumulation. In the end, verification tests are designed to validate the feasibility and practicability of resolving TAN accumulation by controlling reflux ratio. In verifying experiment, when reflux ratio is set at 0.85, TAN concentration of UASB effluent is increased to a constant value, which is 1 900 mg/L. Furthermore, the accumulated TAN has no negative influence on the population and activity of methanogens, on the contrary, it develops the buffer capacity to acid and alkaline and keeps the anaerobic system more steadily. To sum up, a method of resolving the problem of TAN accumulation by controlling reflux ratio of digestive effluent has been ascertained radically, and the method can be used in the preventing of ammonia inhibition in two-phase anaerobic digestion process.

国家水体污染控制与治理科技重大专项(2009ZX07104-002-04)；重庆市科技重大专项(CSTC2008AB7135)；重庆大学研究生创新团队建设项目 (200909B1003)