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151.
随着《环评法》的颁布实施,环评市场不断扩大,本文针对杭州市余杭区环评价格高低有错、环评质量良莠不齐的现象,分析了环评机构间的环评价格博弈关系、环评机构与环保管理部门间的环评质量博弈关系,并指出环保管理部门适当融入到环评市场中有利于突破"囚徒困境"及"小偷与守卫"博弈,引导环评市场健康、有序发展。  相似文献   
152.
本文以排污权交易的核心业务排放跟踪管理为出发点,选择电厂二氧化硫指标进行排放跟踪数据过程校核体系研究,探索进一步提高排污权交易体系中排放数据准确性的机制。  相似文献   
153.
2006年8月15日,由于操作人员安全意识淡薄,处理过程中严重违章,某石化分公司芳烃联合装置变压吸附制氢(PSA)装置发生一起高压氢气泄漏事件,险些造成恶性事故.  相似文献   
154.
对西南山地某铅锌矿区耕地土壤(旱地和水田)和主要谷物类产品(小麦、玉米和稻米)进行取样调查,分别测定并分析了土壤和谷物中Pb、Zn、Cu、Cr、Cd、As等重金属的含量.同时,通过Nemero综合污染指数评价了矿区耕地土壤的污染状况,并利用MMSOILS风险评价模型评价了食用当地谷物类产品对成人和儿童造成的重金属健康风...  相似文献   
155.
水蚯蚓对硝化细菌活性影响的试验研究   总被引:4,自引:2,他引:2  
采用SBR反应器富集培养富含硝化细菌的活性污泥,利用填料挂载的方法向SBR反应器投加水蚯蚓,考察了水蚯蚓对SBR反应器硝化效率及硝化细菌活性的影响.结果表明,SBR反应器挂载水蚯蚓后,SBR系统的硝化速率降低了16.65%,NO2--N氧化率减少量约为24%.通过对SBR系统单一周期各形态氮素浓度变化规律进行考察,发现...  相似文献   
156.
A systemic health risk assessment for the chromium cycle in Taiwan   总被引:4,自引:0,他引:4  
Health risk assessment (HRA) has been recognized as a useful tool for identifying health risks of human activities. In particular, this method has been well applied to spatially defined units, such as a production plant, a treatment facility, and a contaminated site. However, the management strategies based on the risk information will be more efficient if the comprehensive picture of total risks from all kinds of sources is depicted. In principle, the total risks can be obtained when all risk sources are assessed individually. Apparently, this approach demands huge amount of efforts. This study develops a methodology that combines substance flow and risk estimation to facilitate examination of risk in a systemic way and provide comprehensive understanding of risk generation and distribution corresponding to flows of substances in the anthroposphere and the environment. Substance flow analysis (SFA) and HRA method is integrated to produce a systemic risk assessment method, from which substance management schemes can be derived. In this study, the chromium cycle in Taiwan is used as an example to demonstrate the method, by which the associated substance flow in the economy and the risk caused by the substance in the environmental system is determined. The concentrations of pollutants in the environmental media, the resultant risks and hazard quotients are calculated with the widely-used CalTOX multimedia model.  相似文献   
157.
提出含油污泥的优化处置方案,并通过生命周期评价方法(LCA)对优化方案进行环境影响评价。结果表明,与原处置工艺相比优化后环境负荷降低了99.62%。  相似文献   
158.
针对焦化废水处理调试运行存在的问题,以实际运行中的焦化废水处理工程为例,介绍了其调试运行过程.指出焦化废水调试及稳定运行的控制要点,并提出调试运行过程中可能出现的问题及解决措施,为同类废水的调试和运行提供参考.  相似文献   
159.
UV-induced degradation of odorous dimethyl sulfide (DMS) was carried out in a static White cell chamber with UV irradiation. The combination of in situ Fourier transform infrared (FT-IR) spectrometer, gas chromatograph-mass spectrometer (GC-MS), wide-range particle spectrometer (WPS) technique, filter sampling and ion chromatographic (IC) analysis was used to monitor the gaseous and potential particulate products. During 240 min of UV irradiation, the degradation e ciency of DMS attained 20.9%, and partially oxidized sulfur-containing gaseous products, such as sulfur dioxide (SO2), carbonyl sulfide (OCS), dimethyl sulfoxide (DMSO), dimethyl sulfone (DMSO2) and dimethyl disulfide (DMDS) were identified by in situ FT-IR and GC-MS analysis, respectively. Accompanying with the oxidation of DMS, suspended particles were directly detected to be formed by WPS techniques. These particles were measured mainly in the size range of accumulation mode, and increased their count median diameter throughout the whole removal process. IC analysis of the filter samples revealed that methanesulfonic acid (MSA), sulfuric acid (H2SO4) and other unidentified chemicals accounted for the major non-refractory compositions of these particles. Based on products analysis and possible intermediates formed, the degradation pathways of DMS were proposed as the combination of the O(1D)- and the OH- initiated oxidation mechanisms. A plausible formation mechanism of the suspended particles was also analyzed. It is concluded that UV-induced degradation of odorous DMS is potentially a source of particulate pollutants in the atmosphere.  相似文献   
160.
The adsorption behaviors of heavy metals onto novel low-cost adsorbent, red loess, were investigated. Red loess was characterized by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectra. The results indicated that red loess mainly consisted of silicate, ferric and aluminum oxides. Solution pH, adsorbent dosage, initial metal concentration, contact time and temperature significantly influenced the efficiency of heavy metals removal. The adsorption reached equilibrium at 4 hr, and the experimental equilibrium data were fitted to Langmuir monolayer adsorption model. The adsorption of Cu(II) and Zn(II) onto red loess was endothermic, while the adsorption of Pb(II) was exothermic. The maximum adsorption capacities of red loess for Pb(II), Cu(II) and Zn(II) were estimated to be 113.6, 34.2 and 17.5 mg/g, respectively at 25°C and pH 6. The maximum removal efficiencies were 100% for Pb(II) at pH 7, 100% for Cu(II) at pH 8, and 80% for Zn(II) at pH 8. The used adsorbents were readily regenerated using dilute HC1 solution, indicating that red loess has a high reusability. All the above results demonstrated that red loess could be used as a possible alternative low-cost adsorbent for the removal of heavy metals from aqueous solution.  相似文献   
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