垃圾渗滤液反渗透浓缩液的蒸发浓缩试验研究

发布时间：2018-01-10 13:04

  本文关键词：垃圾渗滤液反渗透浓缩液的蒸发浓缩试验研究　出处：《西南交通大学》2017年硕士论文　论文类型：学位论文

  更多相关文章： 渗滤液反渗透浓缩液 负压真空蒸发 方差分析 最佳操作条件

【摘要】：近年来,为了更好地满足生活垃圾填埋场污染物控制的要求,新型膜分离技术已被大量应用在我国垃圾渗滤液处理领域。反渗透(R0)作为膜分离技术的典型工艺之一,会在运行过程中产生膜滤浓缩液。浓缩液具有污染组分复杂、浓度较高、电导率高等特点,需进行进—步妥善处理。目前浓缩液的处理方法有多种,都存在各自的优势和不足,而组合工艺能发挥最大优势,弥补各方法的劣势。结合组合工艺处理浓缩液的需求,本论文对浓缩液进行蒸发再浓缩,将污染物与水分分离,以便于各自最终的无害化处理。本论文将重点研究浓缩液负压真空蒸发过程中水分和污染物分离特性,具体工作和结论如下:(1)以成都市长安垃圾填埋场的渗滤液反渗透浓缩液为研究对象,检测其水质指标和物理特性。结果表明浓缩液具有电导率高、有机污染浓度高、氨氮含量较低的特点,物理特性接近于水。(2)针对以上水质特征,选取并设计合适的蒸发设备。蒸发器类型选取单效强制外循环蒸发器,加热装置选取履带式电加热器,再以板式换热器为冷凝器,与各装置组装连接成蒸发系统。(3)研究冷凝液水质变化,确定适宜蒸发时间。以70℃C、0.07MPa真空度和7.58的pH值作为蒸发条件,发现蒸发前12min,冷凝液中COD值随时间增加略有升高,而氨氮、pH值、电导率值则逐渐下降;12min后冷凝液中各指标值趋稳。确定12min为适宜蒸发时间。(4)研究主要控制因素对污染物分离效果的影响,并确定最佳操作条件。试验表明,真空度(温度)和原液pH值是影响冷凝液水质的主要控制因素。设置交叉分组全试验,对试验结果做方差分析,用最小显著差数法进行多重比较,再权衡运行中的利弊因素,最终确定了负压真空蒸发的最佳操作条件:真空度选取0.085MPa,pH值为7.58。本论文通过负压真空蒸发试验研究,实现了反渗透浓缩液污染物和水分的有效分离,得出了最佳操作条件,为反渗透浓缩液的蒸发浓缩实际应用提供有力的参考和借鉴。
[Abstract]:In recent years, in order to better meet the requirements of municipal solid waste landfill pollutant control. New membrane separation technology has been widely used in the field of landfill leachate treatment in China. Reverse osmosis (R0) is one of the typical membrane separation technologies. Membrane filtrate concentrate will be produced in the process of operation. The concentrated liquid has the characteristics of complex pollution component, high concentration, high conductivity, and so on, which need to be properly treated by step by step. At present, there are a variety of treatment methods of concentrated liquid. Each has its own advantages and disadvantages, and the combined process can play the greatest advantage and make up for the disadvantages of each method. Combined with the combined process to deal with the needs of concentrated liquid, the concentrated liquid is evaporated and reconcentrated in this paper. In order to separate pollutants from water in order to facilitate their final harmless treatment, this paper will focus on the characteristics of separation of water and pollutants during vacuum evaporation of concentrated liquid under negative pressure. The specific work and conclusion are as follows: (1) taking the leachate reverse osmosis concentrate of Chengdu Changan landfill as the research object, the water quality index and physical characteristics of the concentrated leachate are tested. The results show that the concentrated liquor has high conductivity. The characteristics of high concentration of organic pollution and low content of ammonia nitrogen. The physical characteristics are close to that of water. (2) according to the above characteristics of water quality, the suitable evaporation equipment is selected and designed. The type of evaporator is single effect forced external circulation evaporator. The heating device selects the tracked electric heater, then takes the plate heat exchanger as the condenser, and assembles with each unit to form the evaporation system. (3) to study the change of condensate water quality and determine the suitable evaporation time. At 70 鈩，

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