石灰石-石膏湿法脱硫系统改造

某电厂300 MW机组由于燃用煤种与设计煤种差别很大,其实际燃煤的含硫量远远超过设计值,造成烟气中SO2排放量成倍增加,不能达标排放,需对其已有脱硫系统进行技术改造,主要是对吸收塔、氧化空气系统、石膏脱水、石灰石浆液供给系统、事故浆液排放系统进行了扩容改造。吸收塔浆液池增高壳体采用塔内立杆倒拉的方法进行顶升安装,上部1.8 m层喷淋层壳体采用吊装。改造后实际运行表明:脱硫率超过96%的设计值,其他指标均达到设计要求,工程改造后每年减排SO2 6.4万t,减排粉尘358 t,每年可节省排污费支出4 032万元,具有显著的社会和经济效益。     

基于RepastS平台的太湖水环境系统承载力研究

运用计算实验方法,以计算机为工具,构造太湖水环境系统承载力模型,通过研究水和人类的各主体行为得出太湖水环境系统的整体特征,并通过人口、TP、TN、CODMn承载度来反映。研究结果表明太湖目前点源污染得到了有效控制,但面源污染和城镇生活用水污染尚需要重点治理。实验显示:通过系统参数的调整,将大大改善太湖现有水环境系统。     

钢铁行业大气环境影响评价方法与建议

按钢铁行业大气环评报告书的结构和顺序,结合HJ 2.2-2008《环境影响评价技术导则大气环境》中的相关技术要求,从评价因子、源强、评价等级、大气监测、大气预测、防护距离等方面出发,分析了钢铁行业大气环评中的评价等级确定、大气监测、大气预测等工作中存在的问题,并提出解决方案和建议对策。     

钼冶炼工艺的循环经济探讨

钼是重要的稀有金属之一,主要通过氧化分解辉钼矿来提取。我国普遍使用反射炉、回转窑等焙烧设备生产氧化钼,造成了严重的SO2污染和资源浪费问题。为改变辉钼矿焙烧分解工艺的污染状况,硝酸高压分解、碱性高压氧分解、次氯酸钠分解和电氧化分解等辉钼矿湿法工艺相继被开发出来。但是这工艺往往只关注在如何获取金属钼等资源,而忽视了辉钼矿中占40%的硫资源。从循环经济角度分析了不同辉钼矿分解工艺的物质流向,探讨符合清洁生产和循环经济精神的工艺革新方向,提出了纯氧氧化焙烧和浓硫酸氧化两种新工艺。     

硫酸系统水平衡分析计算和生产实践

在硫酸系统中,通过水平衡分析计算烟气带入净化工序的SO2体积分数和含水量,确定净化工序的能力,控制干燥塔进口烟气温度,使干吸工序生产出合格产品;通过计算,烟气带入净化工序的水量小于产品带出的水量,制酸净化污水经过污水处理工序处理后返回到净化工序重复使用,实现净化污水零排放,消除对环境的污染.     

Potential of secondary aerosol formation from Chinese gasoline engine exhaust

Light-duty gasoline vehicles have drawn public attention in China due to their significant primary emissions of particulate matter and volatile organic compounds(VOCs). However,little information on secondary aerosol formation from exhaust for Chinese vehicles and fuel conditions is available. In this study, chamber experiments were conducted to quantify the potential of secondary aerosol formation from the exhaust of a port fuel injection gasoline engine. The engine and fuel used are common in the Chinese market, and the fuel satisfies the China V gasoline fuel standard. Substantial secondary aerosol formation was observed during a 4–5 hr simulation, which was estimated to represent more than 10 days of equivalent atmospheric photo-oxidation in Beijing. As a consequence, the extreme case secondary organic aerosol(SOA) production was 426 ± 85 mg/kg-fuel, with high levels of precursors and OH exposure. The low hygroscopicity of the aerosols formed inside the chamber suggests that SOA was the dominant chemical composition. Fourteen percent of SOA measured in the chamber experiments could be explained through the oxidation of speciated single-ring aromatics. Unspeciated precursors, such as intermediate-volatility organic compounds and semi-volatile organic compounds, might be significant for SOA formation from gasoline VOCs. We concluded that reductions of emissions of aerosol precursor gases from vehicles are essential to mediate pollution in China.     

采用零价铁-缓释碳修复氯代烃污染地下水的中试研究

针对受氯代烃污染的地下含水层,采用零价铁-缓释碳技术进行修复中试研究。中试期间,向地下9～18 m受氯代烃污染的含水层(体积900 m3)注入7 200 kg零价铁-缓释碳药剂。对地下水中污染物进行定期监测,结果显示:零价铁-缓释碳技术可以高效地将地下含水层中的氯代烃污染物脱氯降解。其中1,2-二氯乙烷的去除率达99.90%以上,1,1-二氯乙烷的去除率达86.00%以上,氯仿的去除率达98.00%以上。在零价铁-缓释碳还原体系存在的条件下,1,2-二氯乙烷、1,1-二氯乙烷和氯仿三种污染物的半衰期分别为46,115,70 d。研究证明:零价铁-缓释碳技术可以高效地修复被氯代烃污染的地下含水层,并且修复期较短,对氯代烃类污染场地地下水的修复有重要的实用价值。     

Multi-factors influencing the spatial distribution of polycyclic aromatic hydrocarbons in soils surrounding drinking water protection zone

We selected the Guanting Reservoir in Beijing, China as a case where an industrial area locates on the upwind corner to study the influence of human activities and natural processes on the distribution of polycyclic aromatic hydrocarbons (PAHs) in soils. Soil PAH concentrations in the study area follow a log-normal probability distribution function, suggesting that distribution of PAH in soils was affected by human activities. Distribution of PAHs in soils was significantly affected by the point source that high PAH concentrations were observed in near industrial area with an obvious declining trend from the northwest to the southeast which was the prevailing wind direction in this area. Away from the influence of point source, distribution of PAHs in soils was found to significantly correlate with total organic carbon content, while the influences of agricultural land uses and type of soil texture on the total soil PAHs contents and ring compositions were quite limited. The results can provide some evidences and data on the pollutant accumulation in drink water protection area influenced by natural processes and human activities.     

基于层次分析法（AHP）的环境绩效审计评价体系构建研究——以丽水市为例

文章构建了环境绩效审计综合评价指标体系,运用层次分析法确定指标体系的权重,对于提高环境绩效审计工作质量和效率具有重要意义。丽水市生态资金绩效审计的实证研究结果表明,指标体系评价结果能客观反映市县行政区实际,指明影响环境管理绩效的消极因素,能有效提高财政经费使用效益,充分发挥审计服务科学发展的作用。     

酞菁-二氧化钛光催化剂的制备及其光催化降解效果

采用溶胶-凝胶法制备酞菁-TiO2光催化剂,并分别掺杂铁、铜、钴、镍元素。酞菁作为光敏化剂,提高TiO2在可见光下对有机染料的降解效果。采用SEM对催化剂进行表征,研究在可见光下酞菁-TiO2光催化剂对5种有机染料(甲基橙、甲基红、甲酚紫、亚甲基蓝和孔雀石绿)的降解效果,结果表明,酞菁铁-TiO2,酞菁钴-TiO2,酞菁铜-TiO2,酞菁镍-TiO2均能有效降解这几种有机染料,光催化反应300 min后降解率达92%。比较4种催化剂对甲基橙的降解率,酞菁钴-TiO2催化剂降解效果最明显,以下是酞菁铁、酞菁镍和酞菁铜-TiO2催化剂。