重庆大学环境与生态学院
X703.1
重庆市建委科技计划项目(城科字第{2015-1-31}号)
College of Environment and Ecology,Chongqing University
我国多数焚烧厂采用“MBR+反渗透”工艺处理渗滤液,该工艺的反渗透膜进水富里酸含量偏高,是导致反渗透膜结垢污染的原因之一。为降低反渗透膜进水中富里酸含量,研究以过硫酸盐协同电化学体系处理自配富里酸废水,讨论体系中去除富里酸的主要活性物质,并考察了初始pH值、过硫酸盐投加量、电流密度、极板间距、NaCl浓度对富里酸去除率的影响。在此基础上,考察协同体系处理实际焚烧厂渗滤液MBR出水的效果。结果表明：过硫酸盐协同电化学体系对富里酸的去除能力主要由SO4－.、.OH和Cl-生成的HClO提供,其中HClO有着较大的贡献,其次是.OH,SO4－.贡献最小。初始pH及极板间距对富里酸去除率的影响不大；富里酸去除率随初始过硫酸盐浓度的增大先升高后降低；随电流密度增加先增加后不变；随Cl-浓度增大而略微降低。其中,过硫酸盐投加量、电流密度是主要的影响因素。采用过硫酸盐协同电化学体系处理实际焚烧厂渗滤液MBR出水,在电流密度30mA/cm2、PS9g/L的条件下反应6h,三维荧光光谱结果显示,可见光及紫外光区富里酸的去除率分别达到98.65%和97.80%。过硫酸盐协同电化学体系能够有效去除实际废水中的富里酸。
The ‘membraneSbioreactor (MBR) + reverse osmosis’ technology is usually applied to treat leachate from most incineration plants in China. Studies have showed that the high fulvic acid concentration in reverse osmosis system influent results in the fouling of membrane. The persulfate synergistic electrochemical system(EC+PS system) was used to reduce fulvic acid concentration. The main active substances for removing fulvic acid in the system were discussed. The effect of initial pH value, persulfate dosage(PS), current density, plate space, NaCl concentration on the degradation of fulvic acid was investigated. The results showed that the removal of fulvic acid was mainly depended on Cl- provided by HClO,.OH and SO4-.in turn. The fulvic acid removal rate decreased slightly with the increase of initial pH and plate spacing,Sincreased firstly and then decreased with the increase of initial PS concentration,Sfirst increased and then remained unchanged with the increase of current density, decreased slightly with the increase of Cl- concentration The current density and persulfate dosage were the main influencing factors for fulvic acid removal . The leachate effluent of MBR from actual incinerator was treated by EC+PS system under the current density 30mA/cm2, potassium persulfate 9g/L and reaction time 6h. The three-dimensional fluorescence spectrum results showed that the removal rate of fulvic acid in visible and ultraviolet regions reached 98.65% and 97.80%, respectively, and the EC+PS system could effectively remove fulvic acid in actual wastewater
