固定化菌藻处理海水养殖废水试验研究

Experimental study on treatment of mariculture wastewater by immobilized bacteria-algae

为验证菌藻共生用于处理海水养殖废水的净化效果,探索高效可行的海水养殖废水处理技术,采用固定化菌藻小球耦合循环式活性污泥工艺(CAST)处理海水养殖废水,并与常规CAST进行对比,以考察其处理效果。结果表明:海水小球藻与细菌构成共生体系处理海水养殖废水可有效去除COD_(Mn)、无机氮和磷,去除率高于青岛大扁藻、杜氏盐藻及等鞭金藻与细菌的搭配;采用海藻酸钠包埋法将菌藻制成固定化小球后,菌藻体积比为1∶2时的脱氮除磷效果较好;将固定化菌藻与CAST工艺相耦合,稳定运行后出水COD_(Mn)的质量浓度低于8 mg/L、无机氮的质量浓度低于0.5 mg/L、磷酸盐(以P计)的质量浓度低于0.1 mg/L。该工艺可以有效利用细菌和微藻对污染物的协同去除作用,可用于海水养殖废水的净化处理。

In order to verify the effect of bacteria-algae symbiosis in the treatment of mariculture wastewater,and to explore an efficient and feasible technology for mariculture wastewater treatment,the bacteria-algae symbiotic system was immobilized and coupled to cyclic activated sludge technology(CAST),which was used to treat mariculture wastewater,the treatment effect was investigated and compared with the conventional CAST.The results showed that,the co-culture system of chlorella vulgaris with bacteria could effectively remove COD_(Mn),inorganic nitrogen and phosphorus in mariculture wastewater,and its pollutants removal performance was better than the co-culture systems of bacteria with platymonas helgolandica,dunaliella salina or isochrysis galbana.When bacteria and chlorella vulgaris were immobilized by sodium algnate,the volume ratio of bacteria to algae was 1∶2,the nitrogen and phosphorus removal efficiency was good.The immobilized bacteria-algae was then coupled to CAST,the mass concentrations of COD_(Mn),inorganic nitrogen,and phosphate(calculated by P)in the effluent water during stable operation were less than 8,0.5 and 0.1 mg/L respectively.The said system took advantage of cooperation between bacteria and algae in removing pollutants,which could be used to purify mariculture wastewater.