聚硅酸钙铝混凝剂处理造纸中段废水

Studies on washing & bleaching effluent treatment with poly-aluminum-calcium-silicate sulfate

以电石渣、硅酸钠、硫酸铝、浓硫酸为原料制备了一种高效复合混凝剂聚硅酸钙铝(PACSS),并将其应用于造纸中段废水的处理。研究了加药量、pH值、沉降时间三个因素对PACSS处理造纸中段废水混凝效果的影响。研究结果表明:PACSS在加药量为37.5mg/L、pH值为7.0、沉降时间为35min的条件下,浊度、CODCr和色度的去除率分别为96.8%,82.8%、96.4%。与传统混凝剂硫酸铝(AS)和聚合氯化铝(PAC)相比,其处理造纸中段废水的效果具有明显的优势。

The poly-alunainum-calcium-silicate sulfate （PACSS） coagulant is a new efficient composite coagulant which was prepared by carbide slag, sodium silicate, aluminum sulfate, and concentrated sulfuric acid. It was applied to the treatment of washing and bleaching effluent in paper mills. The influence of PACSS coagulant dosage, pH value and sedimentation time on the coagulation was examined. The results show that PACSS can reach a better results in the treatment of washing and bleaching effluent than AS and PAC. The optimal treating condition are as follow： PACSS dosage 37.5mg/ L, pH value 7.0 and sedimentation time 35 minutes, under which conditions the removal rates of the turbidity, CODer and chroma can reach 96.8%, 82.8%, 96.4% respectively. It proved that PACSS coagulant is superior to conventional coagulant PAC and AS in the treatment of washing and bleaching effluent in paper mills.