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131.
从源项调查的目的、意义、基本内容和主要方法等方面进行了研究,分析了国内该方面研究工作的主要动态,指出了目前源项调查工作存在的主要问题,并对退役治理工作提出了合理的建议。 相似文献
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134.
介绍了晶安高科污染源的来源、采取的措施及综合治理、利用方法.使废水指标由PH11~12;SS<1000mg/l;CODcr≤200mg/l;氨氮≤200mg/l降到PH6~9;SS<70mg/l;CODcr≤100mg/l;氨氮≤15mg/l;酸雾指标由HCl500~800mg/m3达到小于25~40mg/m3;炉窑烟气由林格曼黑度5,烟尘浓度2700~5191mg/Nm3降到林格曼黑度1,烟尘浓度小于200mg/Nm3;硅渣可生产复合絮凝剂和白炭黑,不仅可改善环境影响,而且可回收盐酸和利用废资源,可给企业带来经济效益. 相似文献
135.
利用非金属材料处理重金属废水 总被引:2,自引:0,他引:2
本文简述了重金属废水的来源及其危害,介绍了几种常用非金属材料在处理重金属废话水方面的应用状况。 相似文献
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137.
某冶炼厂附近农田镉污染调查与对策 总被引:5,自引:2,他引:3
对遭受某铜矿冶炼厂镉污染的湖北省某镇约30km^2的农田土壤进行了调查,对土壤耕作层与亚耕层以及污染源(废气、废水和炉渣)中全量Cd和有效态Cd含量的系统测定结果表明:未受Cd污染、受轻度污染及受中度污染的土壤面积分别占3.6%,82.1%,14.3%;土壤中全量Cd及有效态Cd含量的分布规律均表现为西灌区>东灌区>灌间区;土壤耕作层与亚耕层中全量Cd含量的差异不大,而有效态Cd则主要富集于土壤耕作层中;受土壤pH值的影响,Cd在污染区土壤中的活化率低于远离冶炼厂未受污染的农田对照区。该镇农田的Cd污染主要来源于某铜矿冶炼厂的废气和废水,而炉渣的污染相对较小。运用生态方法治理该镇农田的Cd污染具有一定的可行性和适用性,值得研究利用。 相似文献
138.
Shehong LI Baoshan ZHENG Jianming ZHU Xiaoying YU 《中国地球化学学报》2006,25(B08):43-44
Uranium and Th are important radioactive elements. Most studies were focused on their environmental impact from uranium deposits and mining sites. But other sorts of mines such as rare metals mines are associated highly with uranium and thorium, too. In China, the Irtysh River is the only river that runs into the Arctic Ocean. The famous Koktokay rare metal pegmatite deposit is located in the headwater region of this river and has been exploited for several decades. The waste ore piled along the riverside as long as several kilometers. The wastewater flom the concentrating plant is discharged into the river directly. In addition, uranium and thorium can be leached from the waste ore into the river in the weathering process. So it is necessary to study the uranium and thorium distribution in the branch and trunk streams of the Irtysh River and the wastewater from the mining site impact on it. In this study, the contents of uranium and thorium in water samples from the Irtysh River and rare metal mine wastewater have been detected directly with ICP-MS. Uranium and thorium distribution and geochemical behaviors in the Irtysh River basin have been studied. The environmental uranium and thorium pollution status in the Irtysh River and wastewater from a rare metal mine impact on it have also been evaluated. The study shows that uranium and thorium contents in wastewater from a rare metal mine are as high as 78.311 μg/L and 0.627 μg/L, respectively, so we should also pay attention to the radioactive pollution from the rare metal mine. The average contents of U and Th in the branch streams of the Irtysh River are 0.572 μg/L and 0.015 μg/L, respectively. At the mean time, in the trunk of the Irtysh River, average thorium content is 0.019 μg/L while U is up to 2.234 μg/L, much higher than the average content (0.0309 μg/L) of the world rivers. From upstream to downstream in the trunk of the Irtysh River, thorium content declines gradually due to dilution by other branches and deposition itself. 相似文献
139.
Hamid Reza Rahmani 《中国地球化学学报》2006,25(B08):110-110
Even though, application of industrial effluent water may alleviate the irrigation water shortage in dry regions such as Iran, but uncontrolled discharge into environment and agricultural land may cause unirreversible harmful damage to environments. Therefore, application of industrial effluent water should consider the environmental consequences such as soil, ground water and food contamination. In this study the effect application of Zob-Ahan effluent water for irrigation water and seepage from evaporation ponds on the chemical composition of surrounding well-water were seasonally investigated from April to March in 2003. The water from the selected well was sampled and analyzed for pH, EC, nitrate, hardness, TSS, TDS, and cations including Na^+, Ca^2+, Mg^2+, anions including SO4^2-, CO3^2-, HCO3^-, Cl^-, and heavy metals including Pb, Cd, Cu, Fe, Cr, Mn, Co, and Zn . The results were compared with standard levels for ground water resources, irrigation water, and direct human consumption. The result shows that the ground water in the vicinity of effluent water application fields and evaporation ponds is contaminated and the concentrations of NO3, Cl and Fe are higher than standard permissible levels for ground water resources. For irrigation or discharge into absorption well the heavy metal concentrations of Cu, Cr, Co, and Fe are limiting. 相似文献
140.
铀水冶尾矿库地下水流特征与模拟分析:以某矿为例 总被引:4,自引:1,他引:3
张金辉 《水文地质工程地质》1998,25(2):38-41
铀水冶尾矿库中地下水流动特征控制了核素向周围环境扩散与迁移。本文以某矿山谷型尾矿库为例,运用二维有限元模拟了库内地下水分布及流动,结合水文地质条件进行了分析与讨论。 相似文献