兼养反硝化工艺协同处理海产品养殖及其加工废水

Synergistic treatment of aquaculture and aquatic products processing wastewater by mixotrophic denitrification process

海产品养殖及其加工废水成分复杂且含盐量大,因此处理难度大。采用兼养反硝化工艺在连续搅拌反应器(CSTR)中对其进行协同处理,以实现碳和氮的同步去除。分析不同盐度时自养和异养反硝化污泥的驯化情况,并研究兼养环境下,进水C N和HRT对自养与异养反硝化协同竞争作用的影响。结果表明:自养异养反硝化污泥的3种驯化方式中驯化效率表现为高盐>低盐-高盐>无盐-低盐-高盐,高盐驯化方式利于脱氮系统的快速启动;在兼养环境下,HRT为8.0 h时NO-2的去除负荷和去除率分别可达0.3 kg(m 3·d)和99.7%,C N为5.0时NO-2及COD去除率分别为99.9%和99.0%,HRT为8.0 h和C N为5.0的运行条件更利于兼养系统运行效能的提高。

The wastewater from aquaculture and aquatic products processing was complex,salty and difficult to be treated.The mixotrophic denitrification process was adopted in continuous stirred tank reactor(CSTR)for simultaneous removal of C and N.The acclimation of activated sludge at different salinity,and the effects of C N and HRT on the synergistic competitive transaction of autotrophic and heterotrophic denitrification in mixotrophic system were analyzed.Results showed that among the three acclimation methods of autotrophic heterotrophic denitrification sludge,the acclimation efficiency was in the order of high salt>low salt-high salt>no salt-low salt-high salt.High salt acclimation method was beneficial for the rapid start-up of denitrification system.In the mixotrophic system,the removal load and removal rate of NO-2 reached 0.3 kg(m 3·d)and 99.7%,respectively,with HRT of 8.0 h.The removal rates of NO-2 and COD reached 99.9%and 99.0%,respectively,with C N of 5.0.Therefore,HRT of 8.0 h and C N of 5.0 were more conducive to the high operating efficiency of mixotrophic denitrification system.