低温真空蒸发处理垃圾渗滤液膜浓缩液  

Treatment of landfill leachate concentrate by low temperature vacuum evaporation

作　　者：宋薇 李丽[2] 王玉如[2] SONG Wei LI li WANG Yuru(China urban construction design ＆ Research Institute Co. Ltd. , Beijing 100084, China School of Tourism and Environment, Shaanxi Normal University, Xi＇an 710119,China)

机构地区：[1]中国城市建设研究院有限公司,北京100084 [2]陕西师范大学旅游与环境学院,西安710119

出　　处：《环境工程学报》2017年第10期5417-5423,共7页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(51508317);陕西省自然科学基础研究计划-青年人才项目(2016JQ2004);公益性行业科研专项(201509055);中国博士后科学基金资助项目(2016M602762)

摘　　要：采用纳滤(NF)和反渗透(RO)工艺处理垃圾渗滤液会产生污染物浓度极高的膜浓缩液。膜浓缩液是一种有毒有害的高浓度有机废水,可生化性差、极难处理,需要选择一种经济有效的浓缩液处理技术。采用低温真空蒸发方法,对膜浓缩液进行蒸发处理。在膜浓缩液水质特征分析的基础上,通过改变膜浓缩液的pH、蒸发温度和蒸发率,分析冷凝液中的COD、NH_3-N、TDS和pH的变化规律。结果表明:1)膜浓缩液初始pH对冷凝液中COD和NH_3-N有较大影响。酸性条件下,冷凝液中COD的浓度相对较高,而NH_3-N的含量很低;碱性条件下,冷凝液中COD的浓度很低,而NH_3-N的含量较高;2)随着蒸发温度的升高,冷凝液的pH、TDS和NH_3-N增加,在70℃达到最大值,继而下降。冷凝液中UV254随着蒸发温度的升高而增加,COD随着蒸发温度的升高而减少;3)在蒸发初期,冷凝液中TDS与NH_3-N含量较高,进一步提高蒸发率,TDS与NH_3-N含量有所降低,至蒸发后期,两者含量略有上升;4)冷凝液中TDS主要来自蒸发进入冷凝液的NH_3-N,冷凝液的TDS浓度与NH_3-N浓度密切相关。本研究有利于拓宽浓缩液处理的途径,为实际应用蒸发处理技术提供有益指导。Landfill leachate treatment by nanofiltration or reverse osmosis produces membrane filtration concentrate which contains high concentration of pollutants.An effective and economic concentrate treatment process is necessary because landfill leachate concentrate is a toxic pollutant with high concentration of organic matter and poor biochemical degradation,which is very difficult to deal with.In this paper,low temperature vacuum evaporation process was used to investigate the treatment of membrane filtration concentrate.Based on the analysis of the characteristics of the landfill leachate concentrate,the effect of some parameters such as pH,temperature,and evaporation rate on the change of condensate was investigated.Experimental results show that,1） the initial pH of membrane filtration concentrate had a significant effect on the COD and NH_3-N of condensate liquid.In acidic conditions,COD concentration of the condensate is very high,but the content of NH_3-N is very low.In alkaline conditions,COD concentration is very low,but NH_3-N content is higher.2） pH,TDS,and ammonia nitrogen of the condensate increased with the increase of operating temperature and reached the highest level at 70℃ and reduced when further increased the evaporation temperature.UV254 of condensate increased with the increment of temperature.However,COD of the condensate decreased with the increase of temperature.3） TDS and NH_3-N of the condensate were high in the early evaporation stage and significantly reduced in the middle evaporation stage with increasing evaporate rate.When further increased the evaporation rate,TDS and NH_3-N were slightly raised in the last stage.4） TDS of the condensate mainly came from ammonia by evaporating intothe condensate and then TDS concentration is closely related to the concentration of NH_3-N.This study can broaden the handling method of membrane filtration concentrate,and provide a useful guidance for practical application of low temperature vacuum evaporation method.

关 键 词：垃圾渗滤液 膜浓缩液 蒸发 冷凝液 

分 类 号：X703.1[环境科学与工程—环境工程]