PAC混凝沉降法处理陶瓷废水操作条件的优化

采用PAC混凝沉降法对陶瓷废水进行处理,考察PAC用量、搅拌强度、搅拌时间、进水pH和沉降时间对处理效果的影响,获得优化的操作条件。实验表明:水样的脱色率、浊度去除率和悬浮物去除率随着PAC用量、搅拌强度、搅拌时间和沉降时间的增大和进水pH的降低而呈现增大的趋势;最佳操作条件为:当废水量小、处理时间充足时,选用PAC用量为12 mg/L、搅拌强度为中速、搅拌时间为10 min、进水pH为6、沉降时间为2 h,此条件下水样的脱色率、浊度去除率和悬浮物去除率分别达到95.6%、95.7%和85.6%;当废水量大、处理时间不充足时,选用PAC用量为60 mg/L,沉降时间为30 min,此条件下水样的脱色率、浊度去除率和悬浮物去除率分别达到94.1%、93.4%和84.4%。证明混凝法对于去除陶瓷废水中的悬浮与胶体颗粒均是有效的。

Optimization of operating conditions for PAC treating ceramic wastewater with coagulation and sedimentation method

Ceramic wastewater was treated with PAC coagulation and sedimentation method.PAC dosage,agitation intensity,agitation time,influent pH and settlement time were respectively observed in order to get optimizational operation conditions.The experimental results show that the sample decolorization,turbidity removal rate and suspended substance removal rate present a trend of increase with the increase of PAC dosage,agitation intensity,agitation time and settlement time,and the reduce of sample influent pH.The best operation conditions showed that when the amount of wastewater was small,and the treatment time was enough,adopting PAC dosage of 12 mg/L,adopting agitation intensity of intermediate speed,adopting agitation time of 10 minutes,adopting sample influent pH of 6 and settlement time of 2 h.Under these conditions,sample decolorization,turbidity removal rate and suspended substance removal rate reached 95.6%,95.7% and 85.6%,respectively.When the amount of wastewater was large,the treatment time was not enough,adopting PAC dosage of 60 mg/L,and settlement time of 30 minutes.Under these conditions,sample decolorization,turbidity removal rate and suspended substance removal rate reached 94.1%,93.4% and 84.4%,respectively.These prove that coagulation method for the removal of suspended and colloidal particles in ceramic wastewater is valid.