摘要根据我国2008年发布的标准,生活垃圾焚烧飞灰可经处理后进入生活垃圾填埋场,飞灰进入填埋场后将受到渗滤液的影响。论文采用SEM、XRD、XRF、消解法及TCLP浸出毒性实验对飞灰的组成及其重金属浸出进行了研究;考虑渗滤液pH、温度、飞灰与渗滤液的固液比以及螯合剂投加量等因素,对飞灰中的As、Cd、Cr、Cu、Pb、Zn等重金属浸出的影响。主要结论为:研究结果表明:飞灰中含有大量的Ca、Na、Cl,约占总量的67%;TCLP浸出实验中扬州飞灰和南京飞灰Pb的浸出浓度均大于在2mg/L;采用EDTA、DTPA固化飞灰,促进了As、Cd、Cr、Cu、Pb、Zn的浸出,扬州已固化飞灰所添加的固化剂能有效降低Zn、Pb的浸出;渗滤液pH在1-11的范围内变化时,Pb在pH=1时的浸出浓度最低,其余重金属浸出浓度变化不大;当混合液即环境pH在1-11范围内变化时,As、Cd、Cu、Cr、Zn浸出浓度随pH增大而减小;探究了25℃和60℃条件下飞灰中重金属的浸出,随着温度的升高,飞灰中大部分重金属的浸出浓度均上升;水洗飞灰可以洗去飞灰中大量含氯盐类,使得飞灰中部分重金属的存在形态改变,溶解性降低,水洗后飞灰中As、Cd、Cu、Cr、Pb的浸出浓度降低。研究为预测飞灰中的重金属在填埋场中的浸出提供指导。76964
毕业论文关键词 飞灰 渗滤液 重金属 填埋场 浸出
毕业设计论文外文摘要
Title The behaviors of MSWI fly ash under landfill conditions
Abstract According to the China’s article which published in 2008, we can find out that municipal solid waste incineration fly ash can be processed into landfill, when the disposal of fly ash satisfies the requirements。 Leachate of landfill is the primarily factor that affect the leaching of heavy metals。 Choosing pH、temperature、solid-liquid ratio and chelating agents as the variables to simulate different environment of Landfill over the experiments of fly ash-landfill leachate system。 On the basis of data, there are several conclusions: Fly ash contains large amounts of Ca, Na, Cl, accounting for about 67% of the total。 Yangzhou Nanjing fly ash and fly ash leaching concentration of Pb were greater than 2mg/L in the TCLP leaching experiments。 The effects of chelating agents that we used in this paper to stabilize heavy metals of fly ash are not good as expecting。 The chelating agent that was used in stabilization of Yangzhou fly ash can effectively reduce leaching of Zn, Pb。 With the increasing of temperature, the concentration of heavy metals leaching is generally on the rise。 The research found that under acidic conditions is more conducive for the leaching of heavy metals than alkaline conditions。 Water can wash away a large amount of soluble salts in the fly ash, in which a large number of chlorine removal help to change some heavy metals in fly ash presence status, and change the solubility and volatility of heavy metals in fly ash。 Research provide a guidance for forecasting heavy metals leached fly ash in landfills。
Keywords fly ash leachate heavy metal landfill leaching
目 录
1 绪论1
1。1 我国城市生活垃圾组成成分及处置方法 1
1。2 飞灰的产生及理化性质 2
1。3 生活垃圾填埋场环境分析 5
1。4 论文研究目标和思路 7
2 生活垃圾焚烧飞灰理化性质的探究 8
2。1 实验材料及设备 8
2。2 实验方法 9
2。3 结果与讨论 9
2。4 小结 14
3 生活垃圾焚烧飞灰在填埋场中的环境行为 15
3。1 实验材料及设备 15
3。2 实验方法 15