利用含铝废盐酸制备聚合氯化铝

以某医药企业产生的含铝废盐酸为原料制备了液体聚合氯化铝(PAC)。确定了适宜的有机物去除方法和碱化剂,考察了碱化剂投加量、废盐酸铝离子含量等合成条件对PAC产品指标的影响,并比较了自制PAC和市售PAC对该企业污水站二沉池出水的混凝效果。实验结果表明:采用活性炭吸附法去除废盐酸中有机物,选择固体CaO作为碱化剂,在活性炭投加量1‰(w)、吸附时间1 h、铝离子含量9.5%(w,以Al2O3计)、CaO投加量80 g/L、反应时间24 h的条件下,制备的液体PAC达到行业标准HG/T 2677—2017《工业聚氯化铝》中的Ⅲ类标准;自制PAC对废水COD和SS的去除率均优于市售PAC,不仅可替代其使用,还可外售产生经济效益。

Preparation of polyaluminum chloride from aluminum-containing waste hydrochloric acid

The liquid polyaluminum chloride （PAC） was prepared using aluminum-containing waste hydrochloric acid from a pharmaceutical company as raw material. The appropriate organic matter removal method and alkalizer were determined. The effects of the synthesis conditions such as alkalizer amount and Al³⁺ content of the waste hydroxide acid on the PAC product index were investigated. And the coagulation effect of the self-made PAC on effluent from the secondary sedimentation tank of the enterprise sewage station was compared with that of commercially available PAC. The experimental results showed that：Under the conditions of removing organic matter in the waste hydrochloric acid by activated carbon adsorption method,using solid CaO as alkalizer,activated carbon amount 1‰（w）,adsorption time 1 h,Al³⁺ content 9.5% （w,calculated as Al₂O₃）,CaO amount 80 g/L and reaction time 24 h,the prepared liquid PAC could reach the class Ⅲ standard of HG/T 2677-2017;The self-made PAC has better COD and SS removal rate than the commercially available PAC,which could not only replace the latter,but also generated economic benefits by sales.