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991.
在成矿作用地球化学与勘查地球化学分析的基础上,选取W、Sn、Mo、B i、Cu、Pb、Zn、Au、Ag、As、Sb、Hg共十二种元素作为南岭地区钨矿勘查的重要指示元素。对这十二种指标元素采用等权平均归一化,相关系数加权累加归一化和异常能归一化三种方法进行处理,都可较好地反映该区钨元素的矿化信息,且均比钨元素单指标异常信息效果显著。相关系数加权累加归一化指标主要反映钨元素信息,而等权平均归一化指标和异常能归一化指标主要反映成矿元素的共同矿化信息,这二者在南岭地区对钨矿成矿信息都具有较好的指示作用。 相似文献
992.
分析了有机污染物在土壤中的迁移转化机理,建立了非平衡吸附作用下渗滤液中有机污染物在土壤中迁移转化的动力学模型,给出了模型的数值解法,模拟出渗滤液在非平衡吸附作用下的污染过程;同时还探讨了模型参数降雨量p,垃圾土土层的厚度h,含水率θ等对有机污染物运移的影响。结果表明:在总的污染源一定的情况下,降雨量的增大和污染土层厚度的增大会使得下层土壤中有机物的浓度降低,为定量研究有机污染物在土壤-水环境系统中分配与归宿提供理论依据,同时也可为监测、治理和恢复地下水污染提供一定的科学根据。 相似文献
993.
采用经活化处理的凹凸棒石粘土,用静态法研究了凹凸棒石粘土吸附铅的吸附酸度、吸附速率、吸附温度和吸附反应热焓以及吸附容量等性能。通过大量实验确定了凹凸棒石粘土吸附铅的最佳条件,并用静态法和交换柱法处理了不同浓度的模拟含铅废水。结果表明,两种不同方法处理效果基本一致,铅的去除率在99%以上,排放液中铅的残余浓度均小于1 mg/L,达到了国家排放标准。选用凹凸棒石粘土对铅、铬、镉等重金属离子的吸附选择性实验,以期为环境污染的控制和治理,提供实验依据。 相似文献
994.
为了使垃圾焚烧发电后的二次垃圾得到合理利用,从而彻底消灭垃圾,利用长春市鑫祥垃圾焚烧发电厂的二次垃圾与适量的高岭土和石英相配比,采用干法压制成型和低温快烧工艺,制备出了性能优异的陶瓷制品。力学性能测试结果显示制品的抗弯强度为41~99.25MPa,吸水率为0.13%~6.95%。XRD、FTIR等测试分析其主晶相是石英。并在正交实验的基础上优选出了再生陶瓷的最佳配方为:二次垃圾∶高岭土∶石英=34∶39∶27,最佳烧成温度是1120℃左右。与相关标准对照可知,制品的主要研发方向为无釉陶瓷地砖、无釉瓷质砖和釉面内墙砖。 相似文献
995.
1 IntroductionSolid wastes (SW) refer to all the wastes derivedfrom human and animal activities, which are normallysolid and are discarded as useless or unwanted (Juha-Heikki Tanskanen, 2000 ). Generally, the organicfraction accounts for more than 50% -60… 相似文献
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998.
Anaerobic digestion is a good method, which possesses the optimal combination of volume reduction, probability of success and potential for resource and energy recovery. However, relatively little research has been done on the anaerobic digestion of organic solid wastes ( OSW ), especially in China.However, different substrates, start-up conditions, micro-organisms, processing technologies, pre-treatment methods could influence the result of anaerobic digestion. Anaerobic treatment of municipal OSW is less than that of wastewaters because some problems and obstructions need to be solved. Meanwhile, the application of anaerobic digestion of OSW is also discussed in the present paper. 相似文献
999.
Effects of local site conditions on the seismic response of municipal solid waste landfills 总被引:3,自引:0,他引:3
P.N. Psarropoulos Y. Tsompanakis Y. Karabatsos 《Soil Dynamics and Earthquake Engineering》2007,27(6):553-563
Over the last decade, the seismic response of landfills made of municipal solid waste has drawn attention mainly due to the environmental and public-health issues that could be raised in the event of a failure. Nevertheless, there are several associated technical issues that have not been adequately investigated. One of these is the impact of local site conditions on the earthquake-induced accelerations and, thereby, on the seismic design of a landfill. This study presents the results of a parametric numerical simulation that has been performed in order to examine the effects of local site conditions on the dynamic response of a typical landfill. Emphasis is given on the special characteristics of ground motion, while the material nonlinearity of both soil and waste is taken into account by an equivalent-linear procedure. Results indicate that local site conditions may play a significant role in the seismic response of a landfill. However, this role cannot be judged a priori as beneficial or detrimental, as it depends not only on soil conditions and seismic excitation, but also on the material and geometric characteristics of the landfill. 相似文献
1000.
The effect of anaerobic co‐digestion of vegetable market waste and sewage sludge was studied extensively. The effects of co‐digestion were compared with the separate digestion of vegetable market waste and sewage sludge. The batch studies were carried out using three bench scale reactors having 1.5 L working volume. The cumulative biogas production shows that the organic waste available from the vegetable waste contains easily biodegradable organic matter compared with the sewage sludge. First order reaction kinetics is maintained throughout the methanation fermentation. The reductions in volatile solids (VS) in the three reactors were in the range of 63–65 %. The specific gas production for vegetable waste was higher (0.75 L biogas/g VSin and 1.17 L biogas/g VSdes) than for the sewage sludge (0.43 L biogas/g VSin and 0.68 L biogas/g VSdes). Consequently, the specific gas production for the co‐digestion of the mixture of vegetable waste and sewage sludge (0.68 L biogas/g VSin and 1.04 L biogas/g VSdes) was considerably higher than for the sewage sludge only. Batch kinetics of anaerobic digestion is useful in predicting the performance of digesters and for the design of appropriate digesters. 相似文献