混凝法处理鱼粉加工废水技术研究

Research on the Treatment for Fishmeal Wastewater by Coagulation Process

鱼粉加工废水COD高,生物碎体多,为降低后续生物处理负荷,研究拟采用混凝法对鱼粉加工废水进行预处理,通过正交实验,考察混凝剂种类、pH值、速度梯度等因素对处理效果的影响。结果表明,聚合硫酸铁絮凝效果优于聚合氯化铝、聚合氯化铝铁、聚丙烯酰胺,COD去除率为45.5%,SS去除率为92.4%;聚合硫酸铁混凝预处理鱼粉加工废水的最佳条件为:投药量为600 mg/L;pH值为7;快搅梯度为200 r/min、120 s,GT值为26 832;慢搅梯度为80 r/min、8 min,最佳总GT值为38 832。

Fishmeal wastewater contains lots of biological fragments and high concentration of COD.In order to reduce the later biological treatment load,fishmeal wastewater are pretreated by coagulation process.The influencing factors,flocculant,pH,speed grade are studied by orthogonal experiment.The results show that PFS has better efficiency than PAC,PFAC and PAM,and the removal rate of COD and SS is 45.5% and 92.4% respectively.The optimal conditions are as follows： dosage 600 mg/L,pH=7,rapid stir speed grade 200 r/min and 120s,GT=26832,slow stir speed grade 80r/min and 8 min and optimal total GT=38832.