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第50卷第2期2018年2月哈尔滨工业大学学报JOURNALOFHARBININSTITUTEOFTECHNOLOGYVol.50No.2Feb.2018DOI:10.11918/j.issn.0367-6234.201611048海藻酸不同存在状态对纳滤膜硅酸盐结垢影响李珍贤,王磊,王佳璇,张一,职瑞,许长青(西安建筑科技大学环境与市政工程学院,西安710055)摘要:为探索硅酸盐结垢过程中,多糖类有机物海藻酸(AA)在纳滤过程中的不同存在状态,即在溶液中与饱和硅酸盐共存、在膜面生成有机污染层,对聚酰胺复合纳滤膜硅酸盐结垢的影响.由过滤实验研究硅酸盐结垢过程中膜通量衰减趋势;结合扫描电子显微镜及原子力显微镜,分析膜表面污染层结构;通过Zeta电位研究静电排斥作用的影响;利用原子力显微镜结合二氧化硅胶体探针分析不同结垢阶段的黏附力特点.结果表明:硅酸盐结垢污染程度为:新膜>AA与硅酸盐共存时(新膜)>AA污染膜.对比新膜的硅酸盐结垢,AA与硅酸盐共存时,可以较弱程度地减轻硅酸盐结垢;然而当AA污染层在膜面形成后,硅酸盐结垢程度显著降低.上述结果表明,AA的不同存在状态对硅酸盐结垢的影响差异很大.关键词:海藻酸;硅酸盐;聚酰胺复合纳滤膜;原子力显微镜;黏附力中图分类号:X703.1文献标志码:A文章编号:0367-6234(2018)02-0059-06EffectofthedifferentexistentstatesofalginicacidonsilicatescalingofnanofiltrationmembraneLIZhenxian,WANGLei,WANGJiaxuan,ZHANGYi,ZHIRui,XUChangqing(SchoolofEnvironmentalandMunicipalEngineering,Xi’anUniversityofArchitectureandTechnology,Xi’an710055,China)Abstract:Thispaperaimedtoinvestigatetheeffectsofthedifferentexistentformsofalginicacid(AA),apolysaccharideorganicmatter,onthesilicatescalingsofpolyamidecompositenanofiltrationmembranes.DifferentexistentformsofAAinnanofiltrationprocesscoexistwithsaturatedsilicateinthefeedwater,andhencegenerateorganicfoulinglayersonthemembranesurface.Thetrendofmembranefluxdeclineduringsilicatescalingwasstudiedbyfiltrationexperimentsandthestructuresofthefoulinglayersonmembranesurfacewereanalyzedbyscanningelectronmicroscopyandatomicforcemicroscopy.Theeffectofelectrostaticrepulsionwasinvestigatedthroughzetapotential.Atomicforcemicroscopecombinedwithsilicacolloidalprobewereusedtoanalyzethecharacteristicsoftheadhesionforcesduringdifferentscalingstages.Theresultsshowedthatthedegreeofsilicatescalingdecreasedintheorderofvirginmembrane>coexistenceofAAandsilicate(virginmembrane)>AA-fouledmembrane.Comparedwiththesilicatescalingofthevirginmembrane,AAcouldweakenthesilicatescalingwhenAAcoexistedwithsilicate.However,whentheAAfoulinglayerhadformedonthemembranesurface,thedegreeofsilicatescalingwassignificantlyreduced.Theaboveresultsindicatedthattheeffectsonsilicatescalingsbroughtb
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