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961.
化学危险品储运项目环境风险评价实例 总被引:7,自引:0,他引:7
以某工厂的危险货物铁路专用线项目为例,对化学危险品储运项目环境风险评价的特点、内容、方法等进行探讨。 相似文献
962.
Tuhkanen Sami Lehtilä Antti Savolainen Ilkka 《Mitigation and Adaptation Strategies for Global Change》1999,4(2):91-112
The reduction of carbon dioxide (CO2) emissions may be quite expensive and it is necessary to consider reduction measures for other anthropogenic greenhouse gases, such as methane (CH4) and nitrous oxide (N2O) as well. Their contribution to the total GHG emission from Finland is about 15–20%. In Finland most of the CH4 emissions are due to waste management, agriculture and burning processes. N2O emissions originate from burning processes, agriculture, industry and atmospheric deposition of nitrogen. The cost-effective reduction of the Finnish GHG emissions has been studied with the EFOM-ENV model, which is a quasi-dynamic linear energy system optimisation model. The target function to be minimised is the total discounted cost for the modelled system. In this study the model has been expanded to cover all well-known anthropogenic CO2, CH4 and N2O sources and reduction measures. The results indicate it is economic to reduce the emissions of CO2, CH4 and N2O in Finland. It is profitable to exploit the economic reduction potential of CH4 and N2O, because then the abatement of CO2 emissions does not need to be as extensive as when the reduction is aimed only at CO2 emissions. The inclusion of CH4 and N2O decreases the annual reduction costs about 20% in the year 2010. 相似文献
963.
《环境科学学报(英文版)》2023,35(3):277-289
Black carbon (BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions () and open biomass burning () transported to Xishuangbanna in 2017. Haze months, between haze and clean months, and clean months in Xishuangbanna were defined according to daily PM2.5 concentrations of >75, 35–75, and <35 µg/m3, respectively. Results showed that the transport efficiency density (TED) of BC transported to Xishuangbanna was controlled by the prevailing winds in different seasons. The yearly contributions to the effective emission intensity of and transported to Xishuangbanna were 52% and 48%, respectively. However, when haze occurred in Xishuangbanna, the average and contributions were 23% and 77%, respectively. This suggests that open biomass burning (BB) becomes the dominant source in haze months. Myanmar, India, and Laos were the dominant source regions of BC transported to Xishuangbanna during haze months, accounting for 59%, 18%, and 13% of the total, respectively. Furthermore, India was identified as the most important source regions of transported to Xishuangbanna in haze months, accounting for 14%. The two countries making the greatest contributions to transported to Xishuangbanna were Myanmar and Laos in haze months, accounting for 55% and 13%, respectively. BC emissions from Xishuangbanna had minimal effects on the results of the present study. It is suggested that open BB in Myanmar and Laos, and anthropogenic emissions in India were responsible for poor air quality in Xishuangbanna. 相似文献
964.
机动车排放模式的比较 总被引:1,自引:0,他引:1
介绍了当前使用频率比较高的几种用于道路交通和机动车辆排放计算和评估的模式,并对其进行了分类比较。 相似文献
965.
966.
陕京二线是继陕京一线之后陕西天然气进京的又一条长输管道。管线横贯陕西、山西、河北三省,直到北京市,全长约851 km。该工程对调整沿线各省市的燃料结构与产业结构,进一步改善首都北京的大气环境质量,为 2008年北京成功举办“绿色、环保奥运”,具有深远的意义。陕京二线大部分线路区域地震地质构造十分复杂,地质灾害类型多样,对管道工程和人民生命财产安全潜在危害严重,查明线路的工程地质条件和各类地质灾害,并采取相应治理措施,对于管道顺利建设和安全营运十分重要。 相似文献
967.
968.
The depletion of fossil fuel reserves and increasing demands for diesel are considered to be important triggers for many of the initiatives that have been taken to search for possible sources for the production of biodiesel from materials available within the country. It is possible to produce biodiesel from waste/used cooking oils (WCO) that is comparable in quality to that of fresh vegetable oil. Not only does reuse of WCO, which can otherwise harm human health, reduce the burden on the government of treating oily wastewater, disposing of the waste, and maintaining public sewers, it also significantly lowers the production cost of biodiesel. In the process of frying, oil undergoes many reactions, leading to the formation of a number of undesirable compounds, such as polymers, free fatty acids, and many other chemicals. This poses challenges in the transesterification of WCO. This article covers different techniques in the production of biodiesel from WCO. It also compares combustion, emissions, and engine performance characteristics of biodiesel from WCO as well as factors affecting biodiesel production from WCO and its economic feasibility. 相似文献
969.
为探究畜禽粪污中雌激素的排放水平和分布特征,采用固相萃取-高效液相色谱串联质谱(SPE-HPLC-MS/MS)分析方法,对上海市典型畜禽养殖类型(猪、奶牛、鸡)排放粪污样品中雌激素含量进行测定.结果表明:猪场粪便、沼渣肥、还田土壤、尿液和沼液样品中5种雌激素(E1,雌酮;E2,雌二醇;E3,雌三醇;EE2,炔雌醇;DES,己烯雌酚)总量分别为94.5 ng/g、35.1 ng/g、0.1 ng/g和8 882.2 ng/L、4 388.6 ng/L,其中E1是排泄物中最主要的雌激素;奶牛场粪便、堆肥、还田土壤、尿液、污水进水及出水样品中雌激素总量分别为84.6 ng/g、16.2 ng/g、0.1 ng/g和2 636.7 ng/L、2 605.6 ng/L、615.7 ng/L,其中E1和E2含量最高;鸡场粪便和堆肥样品中雌激素总量分别为60.9和17.5 ng/g.研究显示,猪场、奶牛场和鸡场排泄物中均含有一定数量的天然和人工合成雌激素,雌激素含量水平总体表现为粪便高于有机肥、尿液高于污水;通过畜禽粪污向环境中排放的雌激素总量表现为猪场>奶牛场>鸡场;厌氧发酵对猪场污水中雌激素具有一定的去除效果,而污水厌氧-好氧净化处理和固体粪高温好氧堆肥对奶牛场排泄物中雌激素具有较高的去除效果. 相似文献
970.
当前海洋塑料和微塑料污染问题是全球研究热点,随着我国陆源垃圾减量化处置率和生活污水处理覆盖率的提高,重新核算我国海洋塑料垃圾和微塑料排放量尤为重要,基于文献已报道的关于海洋塑料垃圾和微塑料排放量估算的方法并结合相关统计数据对我国相应排放量进行了核算.结果表明:2016年我国向海洋中排放塑料垃圾124×104~331×104 t,略低于2010年的132×104~353×104 t;生活污水处理厂向环境中排放塑料微珠约109.95×1012粒(折合131.78 t),远低于2014年报道的209.7×1012粒(折合306.9 t).此外,2016年我国生活污水处理厂向环境中排放合成化学纤维类微塑料约1 296.95×1012个(折合648.48 t),轮胎与地面摩擦产生合成橡胶轮胎粉尘约78.85×104 t;合成化纤类微塑料和合成橡胶轮胎粉尘等已成为陆源微塑料的重要来源.通过与发达国家和地区在海洋垃圾和微塑料污染、陆源垃圾处置、海洋垃圾污染应对等方面进行比较,未来我国应通过完善"限塑令"和生活垃圾分类体系、尽早实施"塑料微珠"限令、明晰生活污水处理厂微塑料排放状况等手段从源头控制排放,此外需有效控制塑料垃圾和微塑料的输送途径,制定和完善相关法律法规和监测标准,提升我国应对海洋塑料垃圾和微塑料污染的能力和国际影响力. 相似文献