单纯形优化法在混凝除磷试验中的应用研究

Application of Simplex Optimization for Coagulation Phosphorus Removal

以天津市纪庄子污水厂二级出水作为研究对象,利用单纯形优化方法,探讨不同混凝剂优化混凝除磷的最优条件。本实验对两种混凝剂硫酸铁、硫酸铝的混凝除磷效果进行了研究,利用单纯形优化方法对两种混凝剂的主要影响因素(混凝剂投加量和pH)进行了优化,从而得出了两种混凝剂去除二级出水中磷的最优条件。结果表明:通过18～25次实验,单纯形即可确定两种混凝剂除磷的最优条件。每种混凝剂的去除率都至少增加了30%。硫酸铁、硫酸铝两种混凝剂对总磷的最大去除率分别为87.25%,95.60%。每种混凝剂对正磷酸盐的去除率大于总磷的去除率。硫酸铁、硫酸铝两种混凝剂除磷的总磷残余浓度分别为0.35 mg.L-1,0.12 mg.L-1,达到0.5 mg.L-1以下的城市污水再生利用景观环境用水水质标准(GB/T18921-2002)。

Based on the secondary effluent of Jizhuangzi sewage treatment plant in Tianjin,the application of simplex optimization for coagulation phosphorus removal was studied.The coagulants studied were ferric sulfate [Fe2（SO4）3] and aluminum sulfate [Al2（SO4）3·18H2O].For each coagulant examined,18～25 experiments were carried out until a maximum removal was observed through the experimental procession.Increases of higher than 30% were found for the removal efficiencies of these two coagulants over the course of the experiments.The maximum removal efficiencies were 87.25% for ferric sulfate;95.60% for aluminum sulfate were obtained through the simplex procession.The orthophosphate removal efficiency was higher than that of total phosphorus for each coagulant.The minimum total phosphorus residuals were 0.35 mg·L-1 and 0.12 mg·L-1,which were accordant with GB/T18921-2002.