矿井水处理中聚丙烯酰胺残留物对反渗透膜污染的贡献  

Impact of polyacrylamide residue on reverse osmosis membrane fouling in mine water treatment

作　　者：郭中权 毛维东 肖艳 郑彭生 马赛 GUO Zhongquan;MAO Weidong;XIAO Yan;ZHENG Pengsheng;MA Sai(CCTEG Hangzhou Research Institute Co.,Ltd.,Hangzhou 311201,China)

机构地区：[1]中煤科工集团杭州研究院有限公司,浙江杭州311201

出　　处：《煤炭学报》2020年第S02期986-992,共7页Journal of China Coal Society

基　　金：中国煤炭科工集团科技创新创业资金专项重点资助项目(2018-2-ZD001)

摘　　要：矿井水预处理单元一般采用混凝沉淀(澄清)过滤工艺去除悬浮物,聚丙烯酰胺(PAM)作为一种有机高分子絮凝剂,广泛应用于矿井水混凝沉淀处理工艺。但PAM反应后残余的丙烯酰胺单体(AM)对人体有害,还会造成后续膜分离工艺的膜污染。矿井水深度处理单元常采用机械过滤(或超滤)+反渗透(RO)工艺除盐,而二次机械过滤对AM去除率较低(<15%),对后续反渗透膜污染风险较大。为了探求矿井水预处理单元PAM残留物AM对后续膜分离单元RO膜污染的贡献,采用L9(34)正交实验和单因素实验分别研究了矿井水RO膜污染影响因素和AM质量浓度对反渗透效果的影响。结果表明,AM质量浓度在0.005~0.050 mg/L、硬度1.02~5.44 mmol/L、电导率1320~3560μS/cm的因素取值内,对RO膜污染阻力影响的显著性关系为硬度>AM>电导率,硬度对膜污染阻力的影响特别显著,AM质量浓度对膜污染阻力的影响显著,AM质量浓度是引发膜污染的重要因素。在AM质量浓度为0.005~0.050 mg/L,随着AM质量浓度的增加,部分AM附着于膜表面并加剧膜污染,RO膜通量减小,由12.02 L/(m2·h)下降至8.18 L/(m2·h),衰减率为31.9%;膜污染阻力增大,由1.96×1012 m-1增加到3.43×1012 m-1,增长率达75%;AM质量浓度对RO脱盐率的影响较小。含有AM的污染膜面表观凹凸感强,膜表面有颗粒物堆积,主要为钙盐结垢,AM对RO膜的污染与化学污染耦合进行,采用质量分数为2%柠檬酸进行化学清洗可有效恢复膜通量。Mine water pretreatment unit generally adopts a coagulation sedimentation(clarification)filtration process to remove suspended matter.Polyacrylamide(PAM)as an organic polymer flocculant is widely used in mine water coagulation sedimentation treatment process.However,the residual acrylamide monomer(AM)after PAM reaction is harmful to human body and will cause membrane pollution in the subsequent membrane separation process.The mechanical filtration(or ultrafiltration)+reverse osmosis(RO)process is often used in the advanced treatment unit of mine water,while the secondary mechanical filtration has a low AM removal rate(<15%)and a high risk of subsequent reverse osmosis membrane pollution.In order to explore the contribution of PAM residue(AM)from mine water pretreatment unit to RO membrane pollution of subsequent membrane separation unit,a L9(34)orthogonal experiment and single factor experiment were used to study the influence factors of RO membrane pollution and AM concentration on reverse osmosis effect.The results show that within the range of factors ranging from AM concentration of 0.005 mg/L to 0.050 mg/L,hardness of 1.02 to 5.44 mmol/L,and electrical conductivity of 1320 to 3560μS/cm,the significant relationship between the effect on the RO membrane fouling resistance is Hardness>AM>Conductivity,hardness has a particularly significant effect on the membrane pollution resistance,AM concentration has a significant effect on the membrane fouling resistance,and AM concentration is an important factor to cause membrane fouling.In the range of AM concentration from 0.005 mg/L to 0.050 mg/L,with the increase of AM concentration,part of AM attach to the membrane surface and increase membrane fouling,the RO membrane flux decreases from 12.02 L/(M2·h)to 8.18 L/(M2·h),and the attenuation rate is 31.9%.The membrane fouling resistance increases from 1.96×1012 m-1 to 3.43×1012 m-1,the growth rate is 75%.The effect of AM concentration on RO desalination rate is small.The surface of the AM-contaminated membrane has a

关 键 词：矿井水处理 聚丙烯酰胺(PAM) 丙烯酰胺(AM) 反渗透 超滤 膜污染 膜污染阻力 

分 类 号：X751[环境科学与工程—环境工程]