腐殖酸对给水处理过滤工艺的影响研究

摘要

用腐殖酸代表水环境中的有机物质来研究,在一定浊度下腐殖酸对石英砂、陶粒、煤质活性炭( CAC)和椰壳活性炭(CSAC)四种不同滤料过滤效果的影响.研究发现,不投加混凝剂时,腐殖酸的存在使各种滤料对浊度的去除效果大大降低；投加混凝剂Al2 (SO4)3·18H2O时,腐殖酸的存在使以浊度和UV吸光度值为代表的颗粒和溶解性有机污染物泄漏时间大大提前.上述两种影响效果都随着实验周期的增加而更加明显,而且依靠单独的反冲洗不能得到恢复；并由此推测,腐殖酸使滤料表面性质发生了变化,这种性质的变化是导致过滤效果降低、泄漏提前的原因之一.%Humic acid was used as the proxy of organic matter in an aquatic environment to study the influence of organic matter on filtration process,wherein four filter media:sand,ceramisite,coal activated carbon (CAC),and the coconut- shell activated carbon ( CSAC),were evaluated at a given influent turbidity level and different humic acid concentrations.The results showed that the presence of humic acid significantly decreases the turbidity filtration efficiency without applying a coagulant.When applying an alum- based coagulant(Al2(SO4)3 · 18H2O),the presence of humic acid caused an early filter breakthrough of particles and DOM characterized as turbidity and UV absorbance,respectively.These effects became more obvious with increasing numbers of the filtration run,and could not be recovered through conventional backwash.It was assumed that the surface property of the media has been changed by humic acid,which caused the decreased efficiency and shorter filtration run length.