连续流处理方式在重金属废水预处理的工程应用

天津某汽车制造厂生产废水污染物种类复杂、水量大,且水质水量波动性较大。将涂装生产工艺的工件初步处理、底漆和面漆3个工段的生产废水依水质不同分为6类,分别进入6个调节池,通过3种不同的预处理方法处理。针对水量大的特点,预处理中采用连续流方式,废水在反应槽内与投加的不同药剂发生反应,再经过斜管沉淀槽的沉淀、反调槽内的反调两个步骤后完成预处理。实践证明,预处理后的废水总镍达到《污水综合排放标准》（GB8978-1996）第1类污染物排放标准,总磷和总锌达到第2类污染物的2级排放标准。

Continuous-flow System Used in A Heavy Metal Wastewater Pretreatment Project

Wastewater from an automobile manufactory in Tianjin has complex pollution,large volume and intensely fluctuation of its quality and quantity,etc.The wastewater from the following three processes in the coating production,such as workpiece preliminary treatment,primer process and topcoat process,is divided into six classes according to their different water quality.The six classes of production wastewater flow into six water regulating tanks and are treated by three different pretreatment processes.According to the characteristic of large water volume,the pretreatment process uses continuous flows method.The wastewater reacts with different medicament in those reaction tanks,and then is treated completely through a pretreatment process after precipitation in the tube settling tank,and is adjusted in its pH in the inverse regulating tank.The pretreatment engineering example showed that the total nickel in the treated wastewater can reach the level of the first class of pollutants of ＂ integrated wastewater discharge standard＂（GB8978-1996）,and the total phosphorus and zinc reach the second level of the second class of pollutants after pretreatment.