无机复合混凝剂处理造纸综合废水

Treatment of Papermaking Wastewater with Inorganic Compound Coagulant

用煤矸石及硫铁矿烧渣作原料制备了一种高效复合混凝剂聚硅酸铝铁(PSAF),并将其用于造纸综合废水的处理。结果表明,在较宽的pH值范围内,PSAF混凝剂对废水有很好的处理效果。在常温、pH值7.0、PSAF用量50mg/L的条件下,SS、CODCr和色度的去除率分别为96.5%、88.6%、92.3%;温度对CODCr去除率的影响不大;与传统混凝剂Al2(SO4)3和FeCl3相比,PSAF混凝剂具有混凝沉降速度快、处理废水后水中残余量低、处理废水费用低等特点。文中还探讨了混凝剂对造纸废水的混凝沉降机理。

A new type of effective complex coagulant polysilicate aluminum ferric salt(PSAF) was prepared from coal gangue and pyrite slag and used as coagulant in the treatment of papermaking wastewater. The experimental results showed that PSAF had a good coagulation effect in the treatment of papermaking wastewater in a wide range of pH value. The removal rate of SS, COD_~Cr and chromaticity was 96.5%, 88.6% and 92.3% respectively in the condition where temperature was normal, pH value was 7.0 and dosage of the coagulant was 50mg/L. The temperature had little impact on the removal rate of COD_~Cr . In comparison with the conventional coagulants, such as Al_2(SO_4)_3 and FeCl_3, the coagulation performance of PSAF was the best. The remarkable characteristics of this method were higher settlement rate and lower cost of treatment. The coagulation mechanism of PSAF coagulant in the treatment of papermaking wastewater was also discussed.