【作者】 刘会平；

【导师】 严家平；

【作者基本信息】 安徽理工大学 ， 环境工程， 2010， 硕士

【摘要】 煤矸石是我国最主要的工业固体废弃物,约占全国工业固体废弃物的20%以上。我国在煤炭开采过程中,产生了大量煤矸石。据不完全统计,全国历年煤矸石累计堆存量约30亿t,年平均排放煤矸石1.5亿t,煤矸石堆放占地近6000hm2。同时,伴随着煤炭资源的开发,全国煤矿地下开采形成的塌陷区已达40万hm2,每年形成塌陷土地区1.5-2万hm2,其中耕地占30%。利用煤矸石对塌陷区进行充填复垦,既能处理煤矸石固体废物,减少煤矸石堆存占地,又能恢复开采沉陷地的利用价值,这是矿区实现综合治理、恢复矿区生态环境的一条有效途径。本文以淮南新庄孜和大通复垦区为研究对象,对复垦土壤生产力、土壤养分、土壤环境质量以及农作物健康安全等方面进行分析评价,综合研究煤矸石复垦土地的复垦效应。结果表明：(1)从覆土40cm到75cm,随着覆土厚度的增加,土壤养分呈增长趋势,当覆土厚度超过75cm以后,养分接近对照土壤的水平,覆土75cm与90cm土壤相比,养分变化出现随机性,养分随覆土厚度无明显增长。覆土75cm、90cm地块的生产力较好,但稍低于对照地块；覆土40cm、60cm地块的生产力都比较差,其有机质、N、P、K等养分普遍偏低,土壤总体肥力太差。(2)采用内梅罗污染指数法对复垦土壤进行环境质量评价,结果表明：在全部30土壤个样品中,28个样品都处于Ⅰ类水平,土壤质量清洁；有1个样品处于Ⅱ类水平,土壤质量尚清洁；还有1个样品处于Ⅲ类水平,土壤受到轻度污染；复垦土壤中Cu、Cd存在超标样品,超标率都为3.33%。参考淮南土壤背景值,对复垦土壤的累积污染指数进行分析,结果显示：复垦土壤中Cu、Ni有显著的累积效应,而Pb、Zn、Cr的累积效应不明显。(3)采用内梅罗污染指数法对复垦区小麦样品进行环境质量评价,结果表明：有1个小麦样品受到轻度污染,其他样品质量都处于清洁或尚清洁的状态,小麦样品受到Pb的轻度污染；对复垦区小麦样品进行人体污染元素暴露健康风险评价,结果表明：复垦土壤中Cu、Cd、Pb、Zn暴露的风险指数都小于1,处于安全水平,而Cr暴露的风险指数为1.21,样品存在健康风险图[18]；表[18]；参[80]更多还原

【Abstract】 Gangue is the largest industrial solid waste, accounting for 20% industrial solid waste in our country. A large number of coal gangue is generated in the coal mining process. According to incomplete statistics, the impact of keeping a total gangue is about 3 billion tons over the years, the average annual emissions of the gangue is 150 million tons, and the area of heaping coal refuse s is near 6000hm2. At the same time, with the development of coal resources, the area of underground subsidence formed by coal mining has reached 400,000 hm2 in the country, the land area collapsed to is form 15,000 to 20,000 hm2 each year which accounted for 30 percent of arable land. The subsidence areas reclamation filling by coal gangue, it can handle solid waste and reduce coal waste storage area as well as restore exploitation of mining subsidence land, which is to achieve comprehensive management of the mining area and restore the ecological environment of a mining area.In this dissertation, reclamation lands of Xin Zhuangzi and Datong in Huainan are the study areas. Study on the reclamation effect of coal gangue reclamation land by analyzing and assessing the soil productivity, soil nutrient, soil environmental quality and food security of reclamation land. The results showed that:(1) The soil nutrient show a rising trend with the increase of the covering thickness from 40cm to 75cm, when higher than 75cm, the soil nutrient is close to the contrast soil. Comparing the 75cm with 90cm, the change of soil nutrient content appears randomly, with no significant increase.The productivity of 75cm,90cm plot is better,but slightly lower than the control plot, which is due to lack of nutrients such as organic matter and P, as well as original soil structure was destroyed in the the reclamation process of filling in the subsidence area, and reclaimed soil requires a maturation process.The productivity of the 40cm,60cm plot is less than the control plot. That is because its nutrients such as N, P, K and organic matte is generally low, and soil fertility is general poor.(2) Using nemerow pollution index method for reclamation soil environmental quality assessment, Results show that:In all 30 soil samples,28 samples are inⅠclass level, and the soil quality is clean; and The soil was slightly polluted; 1 sample is inⅡclass level, and the soil quality is slightly clean,1 sample is in III class level; the content of Cu and Cd in some samples is out-of-specification, all ratios are 3.33%. Reference soil background values of Huainan, the cumulative pollution index of soil reclamation were analyzed, shows that:the cumulative effect of Cu and Ni are significant, and cumulative effect of Pb, Zn, Cr are not obvious.(3) Using nemerow pollution index method for wheat sample environmental quality assessment, show that; 1 wheat sample is slightly polluted, other sample quality is clean or is slightly clean, slightly polluted by Pb; making exposure risk assessment for human body health elements polluted of soil reclamation, show that:all of the risk index of Cu、Cd、Pb、Zn are less than 1, in the safety level, but the risk index of Cr is 1.21, sample have health risk.Figure[18]; table[18]; reference[80]更多还原