低温胁迫下包埋厌氧氨氧化污泥颗粒的脱氮性能

Denitrification performance of anaerobic ammonium oxidation sludge particles encapsulated by polyvinyl alcohol-alginate gel under low temperature stress

为解决在厌氧氨氧化反应进程中,厌氧氨氧化菌抗低温能力较差的问题,以聚乙烯醇-海藻酸钠为包埋剂包埋厌氧氨氧化污泥颗粒,采用UASB反应器研究了HRT对驯化过程中氨氮和亚硝态氮去除效果的影响,考察了温度变化对低温下包埋厌氧氨氧化菌颗粒脱氮效果的影响。结果表明,当进水氨氮浓度为50 mg/L,HRT为7 h时,投加15%包埋污泥后的UASB反应器具有较强的脱氮能力,对NH4^+-N、NO2^--N的去除率分别为95%和89%。相同条件下,水温从30℃阶梯式降低到14℃时,包埋厌氧氨氧化菌颗粒对NH4^+-N的去除率从95%下降为70%,对NO2^--N的去除率从89%下降为63%。在14℃下运行期间,调节水力停留时间为11 h可以提高脱氮效果,NH4^+-N、NO2^--N去除率分别在85%和79%左右。采用聚乙烯醇-海藻酸钠为包埋剂包埋厌氧氨氧化细菌,能大幅度提高低温胁迫下的脱氮性能。

In order to solve the issue of poor low temperature resistance of anaerobic ammonia oxidizing bacteria in the process of anaerobic ammonia oxidation(ANAMMOX),the polyvinyl alcohol-sodium alginate was used as embedding medium to embed ANAMMOX sludge granules.The effect of HRT on the removal of ammonia nitrogen and nitrite nitrogen by UASB reactor during domestication was investigated.The results showed that UASB reactor with 15%embedded sludge had strong denitrification ability when the influent ammonia nitrogen concentration was 50 mg/L and HRT was 7 h.The removal rates of NH4^+-N and NO2^--N were 95%and 89%respectively.Under the same conditions,the removal rate of ammonia nitrogen and nitrite nitrogen decreased from 95%to 70%and from 89%to 63%when the water temperature was stepped down from 30℃to 14℃.The removal efficiency of NH4^+-N and NO2^--N could be improved by adjusting hydraulic residence time to 11 h at 14℃,which were about 85%and 79%respectively.The denitrification performance of ANAMMOX bacteria under low temperature stress could be greatly improved by embedding it with polyvinyl alcohol-sodium alginate.