混凝沉淀处理煤制甲醇废水的实验研究

Experimental study on treatment of coal-to-methanol wastewater by coagulating sedimentation

为进一步提高煤制甲醇废水中SS及COD的去除效果,采用混凝沉淀工艺对煤制甲醇废水进行预处理。通过混凝搅拌实验分析混凝剂加药量、混凝时间、PAC与PAM复配投加对浊度及COD去除效果的影响。结果表明：在PAC、PAFC及PFS三种混凝剂中,最佳混凝剂为PAC;在PAC加药量为60 mg/L的情况下,最佳混凝时间为20~25 min;在PAC投加60 mg/L、非离子型PAM投加0.2 mg/L、混凝20 min的条件下,PAC与PAM复配投加可避免胶体再稳,并将浊度及COD的去除率分别提高至81.8%和12.5%。

This paper arises from the need to further improve the removal effects of SS and COD in coal-to-methanol wastewater using coagulating sedimentation as a pretreatment process to pretreat coal-tomethanol wastewater and analyzing the impacts of coagulation tests on coagulant dosage,coagulation time,compound addition with PAC and PAM. The results show that PAC is the best coagulant of three coagulant agents—PAC,PAFC and PFS; the best coagulation time is 20 ~ 25 min in the presence of the PAC dosage of 60 mg / L; compound addition of PAC and PAM can avoid the new stability of colloids and raise the removal rates of turbidity and COD to 81. 8% and 12. 5%,as in the case of the dosage of60 mg / L PAC and 0. 2 mg / L nonionic PAM.