渗滤液反渗透浓缩液回灌系统中盐分的迁移转化规律

Research on regularity of migration and transformation of salinity in process of leachate reverse osmosis concentrate recirculation

为更科学合理的指导渗滤液浓缩液回灌,减少浓缩液回灌系统中盐分的累积,论文对渗滤液反渗透浓缩液回灌系统中盐分的迁移转化机理进行了研究。采用成都市某垃圾填埋场的渗滤液反渗透浓缩液,对装填了填埋龄为1、5和15 a垃圾的垃圾柱开展了回灌实验,研究了回灌出水中Na^+、K^+、Cl^-和NO_3^-的变化规律,并且对回灌前后的垃圾体进行了离子不同形态的含量分析,初步探索了盐分的迁移转化机理。结果表明,埋龄为1 a的垃圾对浓缩液中盐分离子的去除以生物作用为主,主要体现在对NO_3^-的降解;埋龄为5和15 a的垃圾的吸附作用对于盐分的截留有着重要的作用,其中15 a垃圾吸附作用去除K^+、Na^+、Cl^-和NO_3^-量占总去除量的比例分别为89.78%、85.88%、84.61%和85.67%。

The regularity of the migration and transformation of salinity in the process of leachate recirculation was researched for the purposes of guiding leachate concentrate recirculation and reducing salinity accumulation.Recirculation experiments were carried out on one,five,and fifteen year old landfill columns with leachate reverse osmosis concentrate from a refuse landfill in Chengdu. The mechanism of salinity migration and transformation was preliminarily explored based on the changes in the concentration of K^＋,Cl^-,NO3^-,and Na^＋in the effluent and the content of the different forms of salinity in the refuse. It was shown that the removal of salinity from one year old landfill refuse was mainly based on biological functions,which is mainly reflected in the degradation of NO3^-. In addition,adsorption has an important effect on the retention of salinity for five and fifteen year old landfill refuse. The removal rates of K^＋,Na^＋,Cl^-,and NO3^- were 89. 78%,85. 88%,84. 61%,and85. 67%,respectively,for fifteen year old landfill refuse.