陕北某煤矿矿井废水的混凝处理试验研究

Coagulation Experimental Investigation of Coal Mine Wastewater in Shanbei

为实现水的重复利用,采用混凝法对陕北某煤矿矿井水进行处理。研究了混凝剂种类、投加量、高分子助凝剂、p H对该矿井水混凝效果的影响。通过Zeta电位、絮体尺寸和絮体强度的测定探讨了混凝机理,提出了工艺控制条件。结果表明:最佳混凝工艺为:p H=8、投加35 mg/L的聚合硫酸铁,出水浊度为6.6 NTU,浊度去除率可达99%,达到了洗煤用水水质标准(GB 50359—2005),可回用于洗煤工艺。研究表明:聚合硫酸铁形成絮体后Zeta电位最接近0,混凝效果最佳。聚合硫酸铁形成絮体尺寸和强度较大但回复系数较小,在工艺中必须严格控制混凝时间和搅拌强度,避免将混凝反应中聚合硫酸铁形成的絮体再次打碎,影响混凝效果。

The metiiod of coagulation treatment was used in the treatment of coal mine wastewater in Shanbei toreuse water. The effects of coagulant type, dosage, polymer flucculant and pH were investions were pH =8 and dosage of PFS was 35 mg/L,The process reduce wastewater turbidity effectively,efluent turbidity was 6.6 NTU and the removal rate of turbidity was 99% ,effluent quality achieved “Coal washing water water quality standards”（GB 50359-2005 ）.Effluent could be reused in coal washing process.Zeta potential of floes formed by PFS was the most close to 0,so the coagulation effect of PFS was best. PFS forming floc＇s size and intensity were bigger, but its reply coefficient was small, so the coagulation time and stirring intensity must be controlled in the process to avoid floe be breaking to affect the coagulation effect.