强化混凝法处理无碳复写纸涂布废水实验研究

Study on Treatment of Carbonless Paper Coating Wastewater by Enhanced Coagulation

关键词:  无碳复写纸涂布废水  强化混凝  厌氧污泥

Key Words:carbonless paper coating wastewater  enhanced coagulation  anaerobic sludge

摘要:以阳离子聚丙烯酰胺（CPAM）为助凝剂，选取聚合氯化铝（PAC）、聚合硫酸铁（PFS）、硫酸铝和硫酸亚铁4种混凝剂对无碳复写纸涂布废水进行常规混凝处理，在此基础上采用厌氧污泥作为强化剂，考察强化剂对混凝法处理涂布废水的强化效果，并对混凝絮体进行粒径和扫描电子显微镜（SEM）分析。结果表明，PAC处理效果优于PFS、硫酸铝和硫酸亚铁，在PAC与CPAM投加量分别为400 mg/L和6 mg/L时处理效果最佳，COD_Cr、固体悬浮物（SS）和色度的去除率分别达到68.6%、98.9%和99.1%；厌氧污泥强化混凝对COD_Cr 的去除具有显著的效果，在PAC、CPAM和厌氧污泥投加量分别为200 mg/L、4 mg/L和10 mL/L时，COD_Cr 去除率达74.6%，比常规混凝处理提高约6个百分点，而PAC和CPAM投加量比常规混凝处理分别减少50%和33%；絮体的粒径和SEM分析表明，厌氧污泥强化混凝处理产生的絮体粒径增大，吸附能力增强，沉淀效果明显增强。

Abstract:Coagulation experiments were performed to find out the optimum coagulant for the treatment of carbonless paper coating wastewater. Four coagulants(PAC， PFS， aluminum sulfate and ferrous sulfate） and coagulant aid(CPAM） were used in the experiments. Enhanced coagulation(EC） using anaerobic sludge in the treatment of coating wastewater was evaluated and the optimized coagulation treatments were determined， in the mean time， the particle size of the flocs produced in the enhanced coagulation treatment were investigated by using laser particle size analyzer and SEM. Results revealed that among the four coagulants， PAC presented greater efficiency in COD_Cr, color and SS removal， which were 69.6%, 99.1% and 98.9%， respectively when at the applied dosages of 400 mg/L for PAC and 6 mg/L for CPAM. Results of enhanced coagulation showed that removal of COD_Cr, color and SS were 74.6%, 97.0%和 95.9%， respectively when the dosages of PAC and CPAM reduced by 50% and 33%， respectively. The particle size analysis and SEM observation of the flocs showed that the floc size and adsorption capacity increased， and the precipitation effect was significantly enhanced．