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41.
以许昌市污染源普查数据为基础,通过现状排放、环境质量控制目标与预测环境质量、污染物削减和浓度贡献分析,核定得到了准确可靠的许昌市二氧化硫环境容量;研究建立的从宏观理想容量到实际容量的多源模型体系,能较好地应用于二氧化硫环境容量研究;A—P值法、AERMOD模型均能较好地模拟污染源与环境空气质量的响应关系,且二者具有较好的一致性,可作为可靠的多源模型广泛应用于中小城市的二氧化硫环境容量核定研究及环境规划管理。  相似文献   
42.
孟超  郭欣 《环境科学与管理》2013,(5):104-108,185
文章主要通过对酸性水气体及硫磺回收工艺特点的介绍与比选,着重分析“无在线炉硫磺回收及尾气处理工艺”(SSR),其中硫回收为一段高温转化,二级催化转化的克劳斯工艺,尾气处理为加氢还原一吸收工艺,并介绍原辅材料成分及处理效率。该工艺能够有效解决石化企业的酸性气及酸水排放问题,具有良好的社会、环境效益显著。  相似文献   
43.
近年来,电力行业发展迅速,燃煤电厂大气污染物控制取得很大成就。在电力行业"十二五"规划中,对节能减排工作提出了更高的要求,其中二氧化硫的削减仍占主要地位。本文就高硫煤地区实施有机胺脱硫工艺进行探讨,论述其应用情况、工艺原理,与传统工艺相比的优势、特点及发展方向。  相似文献   
44.
对新乡市9个污水处理场污泥预处理后,用测硫仪分析污泥含硫量,并用经验公式根据年污水处理量,估算焚烧污泥方法年二氧化硫排放总量。结果显示:用测硫仪测定污泥含硫量,核算二氧化硫排放量,与现有方法相比,操作简便易行,结果不受采样条件、时间、环境、布点等因素影响,重现性好、完整、精密。同时发现部分污泥含硫量超过规定用煤中含硫量,建议用焚烧方法处置污泥,净化尾气。  相似文献   
45.
This paper presents the experimental investigations of the emissions of SO2, NO and N2O in a bench scale circulating fluidized bed combustor for coal combustion and co-firing coal and biomass. The thermal capacity of the combustor is 30 kW. The setup is electrically heated during startup. The influence of the excess air, the degree of the air staging, the biomass share and the feeding position of the fuels on the emissions of SO2, NO and N2O were studied. The results showed that an increase in the biomass shares resulted in an increase of the CO concentration in the flue gas, probably due to the high volatile content of the biomass. In co-firing, the emission of SO2 increased with increasing biomass share slightly, however, non-linear increase relationship between SO2 emission and fuel sulfur content was observed. Air staging significantly decreased the NO emission without raising the SO2 level. Although the change of the fuel feeding position from riser to downer resulted in a decrease in the NO emission level, no obvious change was observed for the SO2 level. Taking the coal feeding position R as a reference, the relative NO emission could significantly decrease during co-firing coal and biomass when feeding fuel at position D and keeping the first stage stoichiometry greater than 0.95. The possible mechanisms of the sulfur and nitrogen chemistry at these conditions were discussed and the ways of simultaneous reduction of SO2, NO and N2O were proposed.  相似文献   
46.
本文论述发展工业型煤产业的重要意义和技术质量保证,洁净煤技术是控制污染和节约能源,提高煤炭资源利用率的重要技术项目,将粉煤生产成型煤,为工业、民用提供洁净的燃料,既充分利用煤炭资源同时改善能源结构,又有显著的环保效益,国家把煤炭产业列入中国洁净煤技术有限发展项目,目前制约型煤产业的发展要造气型和燃烧型煤并举,同时有利于用户的节能效益。  相似文献   
47.
通过对葫芦岛市工业源二氧化硫普查结果全面系统分析,阐明了各区域、行业、企业的二氧化硫产生、排放及分布特点,指出了葫芦岛地区工业源二氧化硫存在的主要问题,提出了具体的对策措施。  相似文献   
48.
The responses of sulfur (S) uptake assimilation-related genes' expression in roots of two rice cultivars to cadmium (Cd), bensulfuron-methyl (BSM) and their co-contamination (Cd+BSM) were investigated by gene-chip microarray analysis and quantitative real-time PCR (QRT-PCR) technology. Treatments of Cd and Cd+BSM induced expression of sulfate transporter and permease genes, and promoted sulfate uptake in rice roots. Cd+BSM could alleviate Cd toxicity to cv. Fengmeizhan seedlings, probably due to Cd+BSM promoting greater S absorption by seedlings. Cd and Cd+BSM induced expression of sulfate assimilation-related genes, and thus activated the sulfur assimilation pathway. Cd and Cd+BSM induced expression of phytochelatin synthase and metallothionein genes, and induced expression of glutathione S-transferases (GSTs), glutathione synthase (GS) and S- containing antioxidation enzyme genes, which detoxified Cd2+. It is suggested that (to cope with the toxicity of Cd, BSM and their co-contamination) the S uptake and assimilation pathway was activated in rice roots by increased expression of related genes, thus enhancing the supply of organic S for synthesis of Cd or BSM resistance-related substances.  相似文献   
49.
Organic matter-induced black blooms(hypoxia and an offensive odor) are a serious ecosystem disasters that have occurred in some large eutrophic shallow lakes in China. In this study, we investigated two separate black blooms that were induced by Potamogeton crispus in Lake Taihu, China. The main physical and chemical characteristics, including color- and odor-related substances, of the black blooms were analyzed. The black blooms were characterized by low dissolved oxygen concentration(close to 0 mg/L), low oxidation-reduction potential, and relatively low pH of overlying water. Notably higher Fe2+and∑S2-were found in the black-bloom waters than in waters not affected by black blooms. The black color of the water may be attributable to the high concentration of these elements, as black FeS was considered to be the main substance causing the black color of blooms in freshwater lakes. Volatile organic sulfur compounds, including dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide, were very abundant in the black-bloom waters. The massive anoxic degradation of dead Potamogeton crispus plants released dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide, which were the main odor-causing compounds in the black blooms. The black blooms also induced an increase in ammonium nitrogen and soluble reactive phosphorus levels in the overlying waters. This extreme phenomenon not only heavily influenced the original lake ecosystem but also greatly changed the cycling of Fe, S, and nutrients in the water column.  相似文献   
50.
Understanding the efectiveness of national air pollution controls is important for control policy design to improve the future air quality in China. This study evaluated the efectiveness of major national control policies implemented recently in China through a modeling analysis. The sulfur dioxide(SO2) control policy during the 11th Five Year Plan period(2006–2010) had succeeded in reducing the national SO2emission in 2010 by 14% from its 2005 level, which correspondingly reduced ambient SO2and sulfate(SO4 2) concentrations by 13%–15% and 8%–10% respectively over east China. The nitrogen oxides(NOx) control policy during the 12th Five Year Plan period(2011–2015) targets the reduction of the national NOx emission in 2015 by 10% on the basis of 2010. The simulation results suggest that such a reduction in NOx emission will reduce the ambient nitrogen dioxide(NO2), nitrate(NO3), 1-hr maxima ozone(O3) concentrations and total nitrogen deposition by 8%, 3%–14%, 2% and 2%–4%, respectively over east China. The application of new emission standards for power plants will further reduce the NO2, NO3, 1-hr maxima O3concentrations and total nitrogen deposition by 2%–4%, 1%–6%, 0–2% and 1%–2%, respectively. Sensitivity analysis was conducted to evaluate the inter-provincial impacts of emission reduction in Beijing-Tianjin-Hebei and the Yangtze River Delta, which indicated the need to implement joint regional air pollution control.  相似文献   
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