煤层气产出水处理与资源化技术研究进展

煤层气田的大规模开发会带来一系列的环境问题,其中,煤层气产出水的污染控制及资源化问题最为突出。综述了国内外煤层气产出水的主要处理工艺和技术,结合我国的主要煤层气田的具体情况,提出了相应的建议。     

深圳市坪山河水污染现状分析及评价

坪山河是深圳的主要河流之一。通过对坪山河在深圳河段的水源现状分析及未来预测,初步探讨坪山河的治理措施。     

基于GIS的太原市街道机动车污染物空间分布特征分析

在研究太原市机动车污染现状的基础上,结合太原市机动车排放因子模型Mob ile6和污染物扩散模型OSPM的计算结果,在G IS平台上绘制了太原市冬夏两季道路机动车污染物排放强度分布图和道路交通污染物浓度分布图,并对可视化结果作了科学的分析,研究结果表明：（1）太原市冬季街道污染总体上要高于夏季,这种趋势以CO的表现尤为明显;（2）街道NOX小时浓度超标率比CO小时浓度超标率更高,在研究的56条路段中,CO小时浓度都没有超过国家二级标准,NOX小时浓度超标率达38.9%（夏季）;（3）NOX污染主要集中在中心区,而建成区周边道路某些路段污染也较严重。     

烘箱法测定水和废水中总铬

针对标准法测定总铬存在的诸多不足,提出了烘箱法测定总铬的新方法。改进法制作的校准曲线相关系数γ0.999,相对标准偏差RSD0.88%,加标回收率为98.3%~101.7%,均优于标准法。     

Cu~(2+)/吡啶/H_2O_2对直接大红4BE的快速脱色研究

为了明确影响Cu2+/吡啶/H2O2对模拟染料(DR4BE)废水脱色的主要因素,采用动力学分析、正交和Box-Behnken实验设计研究了不同溶液pH、Cu2+、吡啶、H2O2浓度及Cu2+、吡啶和H2O2组合对初始脱色速率常数和最终脱色率的影响.同时,采用自由基抑制、H2O2催化分解实验探索了Cu2+/吡啶/H2O2对染料的脱色机理.结果发现,Cu2+/吡啶/H2O2能有效使DR4BE快速脱色,脱色效率远高于Cu2+/H2O2;pH是影响初始脱色速率最重要的因素,吡啶、Cu2+及pH是影响最终脱色率最重要的因素;溶液pH在7.0左右时有利于该脱色过程的快速进行.Cu2+与吡啶的交互作用相对较强,吡啶、Cu2+与H2O2的交互作用相对较弱.羟基自由基氧化是Cu2+/吡啶/H2O2对染料DR4BE初始快速脱色的主要机理.研究结果还表明,Cu2+/吡啶/H2O2体系可用于中性条件下染料废水的快速脱色处理.     

A comparative investigation of NdSrCu_(1-x) Co_x O_(4-δ) and Sm_(1.8) Ce_(0.2) Cu_(1-x) Co_x O_(4-δ) (x:0–0.4) for NO decomposition

A series of single-phase T-structured NdSrCu 1-x Co x O 4-δ with oxygen vacancies and T -structured Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ (x: 0–0.4) with oxygen excess were prepared using ultrasound-assisted citric acid complexing method, and characterized by means of techniques such as thermogravimetric analysis and NO temperature-programmed desorption (NO-TPD). The catalytic activities of these materials were evaluated for the decomposition of NO. It was found that the NdSrCu 1-x Co x O 4-δ catalysts were of oxygen vacancies whereas the Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ ones possessed excessive oxygen (i.e., over-stoichiometric oxygen); with a rise in Co doping level, the oxygen vacancy density of NdSrCu 1-x Co x O 4-δ decreased while the over-stoichiometric oxygen amount of Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ increased. The NO-TPD results revealed that NO could be activated much easier over the oxygen-deficient perovskite-like oxides than over the oxygen-excessive perovskite-like oxides, with the NdSrCuO 3.702 catalyst showing the best efficiency in activating NO molecules. Under the conditions of 1.0% NO/helium, 2800 hr -1 , and 600–900°C, the catalytic activity of NO decomposition followed the order of NdSrCuO 3.702 NdSrCu 0.8 Co 0.2 O 3.736 NdSrCu 0.6 Co 0.4 O 3.789 Sm 1.8 Ce 0.2 Cu 0.6 Co 0.4 O 4.187 Sm 1.8 Ce 0.2 Cu 0.8 Co 0.2 O 4.104 Sm 1.8 Ce 0.2 CuO 4.045 , in concord with the sequence of decreasing oxygen vacancy or oxygen excess density. Based on the results, we concluded that the higher oxygen vacancy density and the stronger Cu 3+ /Cu 2+ redox ability of NdSrCu 1-x Co x O 4-δ account for the easier activation of NO and consequently improve the catalytic activity of NO decomposition over the catalysts.     

Releases of phosphate fertilizer industry in the surrounding environment: Investigation on heavy metals and polonium-210 in soil

Distribution of Cu,Zn,Pb,Cr,Ni,Mn concentrations and the activity of polonium-210 in the surrounding area of a phosphate fertilizer industry located on the eastern coast of the Mediterranean Sea has been determined.Nineteen sampling sites were distributed around the industrial zone on a surface area of about 100,000 m2.Atomic absorption spectroscopy and Alpha spectroscopy were used to quantify the heavy elements and polonium-210,respectively.Investigation on a particle scale was conducted by TEM and SEM coupled to EDX and X-ray cartography to determine the nature of heavy elements carriers and their distribution.Heavy elements were mainly concentrated inside the particle size fraction 50 μm.Their levels decreased with distance increasing from the industry.According to the reference soil,enrichment factors were about 10,15,32 and 100 times for Zn,Pb,Cu,and Cr,respectively inside the particle size fraction 50 μm on the closest sites to the industry.The main contaminant sources were transport and storage of row materials and the free release of phosphogypsum waste.Heavy elements were entrapped inside agglomerates of sulfates,phosphates and iron oxihydroxides in a di used shape.Polonium-210 with an enrichment factor of about 56,showed the same behavior of the spatial distribution of the trace elements.     

Changes in functional structure of soil bacterial communities due to fungicide and insecticide applications in canola

The fungicide vinclozolin and insecticide λ-cyhalothrin are widely used to control canola (Brassica spp.) diseases and insect pests, respectively, in Canada. We investigated non-target effects of these pesticides, applied at recommended rates, on soil microbial biomass, functional bacterial diversity and functional community structure of soil bacteria (by evaluating patterns of C substrate utilization) in canola rhizosphere and bulk soil at three locations in Alberta from 2002 to 2004. Experimental treatments were (a) untreated control, (b) vinclozolin fungicide foliar application, (c) λ-cyhalothrin insecticide foliar application, and (d) vinclozolin and λ-cyhalothrin applications. No significant pesticide effects on soil microbial biomass or functional bacterial diversity were observed, but the functional structures of soil bacteria were altered. In 1 of 12 cases, the control treatment had a different soil bacterial community structure from the 3 pesticide treatments. The fungicide treatment had different bacterial community structures from the control or insecticide treatments in 3 of 12 cases, the insecticide treatment had different community structures from the control or fungicide treatments in 4 of 12 cases, and the combined fungicide and insecticide treatment had different community structures from the other treatments in 3 of 12 cases. Therefore, evaluating soil bacterial functional structures revealed pesticide effects that were not detected when bacterial diversity or microbial biomass were measured in canola rhizosphere or bulk soil.