生物炭固定低温混合菌在人工湿地中的应用

Application of Biochar Fixed Low Temperature Mixed Bacteria in Constructed Wetland

为有效解决我国北方冬季污水处理效率低的问题,以低温混合菌为研究对象、以聚乙烯醇(PVA)和海藻酸钠(SA)复合材料为包埋载体、700℃条件下制备的污泥生物炭为吸附载体,在6~8℃,通过正交实验设计,探索优化的固定化条件;探索污泥生物炭对低温混合菌吸附固定化、人工湿地水体中污染物去除效率的影响。结果表明,PVA、SA、污泥生物炭载体的质量分数分别为6%、2%、1.4%,交联时间4 h时,小球的固定化效果、对污水中污染物的去除率最好。在冬季人工湿地中,固定化小球适宜含菌量为15 m L,此时对污水中COD、TN、NH4+-N和TP有较高的去除率,且去除性能较稳定。生物炭固定化混合菌小球对人工湿地水体中污染物的吸附降解过程符合一级反应动力学模型。

In order to solve the problem of low sewage treatment efficiency in cold winter in northern China,the low temperature mixed bacteria as the research object,the composite material of polyvinyl alcohol(PVA)and sodium alginate(SA)was selected as the entrapment carrier,and the peat prepared at 700℃was used as the adsorption carrier.At the temperature of 6~8℃,the optimum immobilization conditions were explored by means of orthogonal test.The effect of sludge biochar dosage on the immobilization of low temperature mixed bacteria and pollutant removal efficiency in water from constructed wetlands were explored.The results showed that,when the mass fraction of PVA,SA and sludge biochar carrier was 6%,2%and 1.4%respectively,and the cross-linking time was 4 h,the immobilization effect of the pellets was the best,and it had the best removal rate for pollutants in sewage.The optimum bacterial content of immobilization pellets in winter constructed wetlands was 15 mL,and the removal rate of COD,TN,NH4+-N and TP in sewage was high,and the removal performance was stable.The adsorption and degradation process of COD,TN,NH4+-N and TP of sewage in constructed wetlands by biochar immobilization mixed bacteria was in accordance with the first-order reaction kinetics model.