纳米TiO2光催化-SBR联合工艺处理制药废水

采用偶联剂法将纳米TiO2附着于聚丙烯多面小球上,以"纳米TiO2光催化-SBR"联合工艺对实际制药废水进行了处理.在光催化降解阶段,以催化剂添加量、光照时间、pH值、H2O2使用量为因素进行正交实验,所得的最佳工况如下:催化剂添加量为54.8mg·L-1 (400个小球),光照时间为4h,pH值为5.0,H2O2使用量为0.5mg·L-1;在SBR处理阶段,沉淀时间为1h,曝气时间为10h,曝气强度为1.25m3·h-1,水力停留时间为26h.在以上工况条件下,联合工艺对CODCr去除率可达到87.66%,BOD5去除率可达到88.59%,SS去除率可达到61.09%,pH值从5 00上升到7.67.可见,运用联合工艺对制药废水进行处理是可行的.

Pharmaceutical wastewater treatment by combined nanometer TiO2 photocatalysis and SBR processes

Nanometer TiO₂ photocatalysis, where nanometer TiO₂ particles are coupled to polyhedral polypropylene balls, was combined with SBR (Sequential Batch Reactor) technology and applied to the actual treatment of pharmaceutical wastewater. In the photocatalysis stage, orthogonal experiments of different factors, for example, dosage of photocatalyst, illumination time, pHand concentration of H₂O₂, were performed. Based on the orthogonal experiments, we obtained the optimal operating parameters: 54.8 mg·L^-1(400 balls), photocatalyst, 4h illumination time, pH5.0 and 0.5 mg·L^-1 H₂O₂. In the SBRstage, the selected operating parameters are: 1 h sedimentation time, 10 h aeration time, 1.25 m³·h^-1 aeration intensity and 26 h hydraulic retention time. When on the combined technology was run at the optimal conditions, the removal rates were: COD_Cr 87.66%, BOD₅ 88.59% and SS 61.09% and the pHincreased from 5.00 to 7.67. Thus, it is feasible to treat pharmaceutical wastewater by these combined photocatalysis and SBRprocesses.