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181.
As part of a comprehensive environmental management system, many countries establish emission control targets for mass emissions of a pollutant. Such targets are often the key objective of an environmental policy, such as an emission trading program. In China, however, it is more than just an objective of one particular policy; it has become a concept that has influenced many national environmental policies and activities. The objective of this article is to review the implementation of the total emission c...  相似文献   
182.
The paper is devoted to the phenomenon of methanogenic activity of woody debris, i.e., methane production in the course of wood decomposition by fungi, which are not directly involved in methane synthesis but form an initial link in the trophic chain leading to methanogenic archaea. Expert evaluation of probable amounts of methane emission is made. The results show that woody debris is an important global source of this greenhouse gas.  相似文献   
183.
苏里格气田试气队伍节能减排工作现状及改进建议   总被引:1,自引:1,他引:0  
苏里格气田试气队伍因涉及数家企业单位,节能减排工作有其特殊性和复杂性。通过调查试气过程中的排污状况,分析了其节能减排工作中出现的几个问题,如计量粗放、管理薄弱、措施简单等,提出了健全管理制度,完善计量系统,鼓励技术研究,加强自主创新,创建统一平台,依靠丙方监管等措施,以促进其节能减排工作健康有序地发展。  相似文献   
184.
曙光油田节能减排现状调查及对策研究   总被引:1,自引:1,他引:0  
曙光采油厂随着超稠油的不断开发,生产能耗也随之增加,通过开展节能减排及节能挖潜工作,全厂能耗增长状态得到了良好的控制,能耗总量由2005年的58.21×10~4t标煤下降到2008年的47.75×10~4t标煤;原油(气)液生产单位综合能耗为52.02 kg标煤/t,同期对比减少0.38 kg标煤/t;生产系统运行效率不断提高。文章详细介绍了曙光油田从机采系统、热注系统、集输系统等方面推广应用节能新技术、新产品,达到其投资和运行费用最少,经济性较好,对油田减排挖潜进行了探讨。  相似文献   
185.
The Singrauli region in the southeastern part of Uttar Pradesh, India is one of the most polluted industrial sites of Asia. It encompasses 11 open cast coalmines and six thermal power stations that generate about 7,500 MW (about 10% of India’s installed generation capacity) electricity. Thermal power plants represent the main source of pollution in this region, emitting six million tonnes of fly-ash per annum. Fly-ash is deposited on soils over a large area surrounding thermal power plants. Fly-ashes have high surface concentrations of several toxic elements (heavy metals) and high atmospheric mobility. Fly ash is produced through high-temperature combustion of fossil fuel rich in ferromagnetic minerals. These contaminants can be identified using rock-magnetic methods. Magnetic susceptibility is directly linked to the concentration of ferromagnetic minerals, primarily high values of magnetite. In this study, magnetic susceptibility of top soil samples collected from surrounding areas of a bituminous-coal-fired power plant were measured to identify areas of high emission levels and to chart the spatial distribution of airborne solid particles. Sites close to the power plant have shown higher values of susceptibility that decreases with increasing distance from the source. A significant correlation between magnetic susceptibility and heavy metal content in soils is found. A comparison of the spatial distribution of magnetic susceptibility with heavy-metal concentrations in soil samples suggests that magnetic measurements can be used as a rapid and inexpensive method for proxy mapping of air borne pollution due to industrial activity.  相似文献   
186.
为获得新疆矿区当前生产规模对应的瓦斯排放基量,调查了研究矿区生产矿井的瓦斯排放现状.根据各矿区2004-2006年生产矿井的开采煤层、生产水平、生产规模和瓦斯排放等参数,对不同矿区和煤田进行了统计分析,计算了新疆矿区当前生产规模对应的瓦斯排放总量,同时对重点瓦斯防治矿区和一般瓦斯防治矿区进行了分类.调查结果表明,新疆矿区煤矿平均吨煤相对瓦斯涌出量由2004年的2.82m3/t增加到2006年的3.09 m3/t,呈逐年递增趋势; 新疆矿区2004-2006年的年平均瓦斯(CH4)排放量为1.05×108 m3/a;准南煤田(I)和塔北煤田(VI)的平均绝对瓦斯涌出量分别占全疆绝对瓦斯涌出总量的64.82%和15.19%,为相对瓦斯富集区,也是当前瓦斯防治的重点区域.按照矿区3年平均绝对瓦斯涌出量(大于1.00m3/min)或平均相对瓦斯涌出量(大于5m3/t)将新疆矿区分为重点瓦斯防治矿区和一般瓦斯防治矿区,并提出了瓦斯分类治理的具体建议.应用灰色系统理论,结合调查数据分别求解了新疆矿区原煤产量与绝对瓦斯涌出量的GM[1,1]预测模型.本研究为新疆煤炭资源后续规模开发过程中的相关环境决策和节能减排政策的实施提供了依据.  相似文献   
187.
Sorbitol and glycerol were used to plasticize sugar beet pulp-poly(lactic acid) green composites. The plasticizer was incorporated into sugar beet pulp (SBP) at 0%, 10%, 20%, 30% and 40% w/w at low temperature and shear and then compounded with poly(lactic acid) (PLA) using twin-screw extrusion and injection molding. The SBP:PLA ratio was maintained at 30:70. As expected, tensile strength decreased by 25% and the elongation increased. Acoustic emission (AE) showed correlated debonding and fracture mechanisms for up to 20% w/w plasticizer and uncorrelated debonding and fracture for 30–40% sorbitol and 30% glycerol content in SBP–PLA composites. All samples had a well dispersed SBP phase with some aggregation in the PLA matrix. However, at 40% glycerol plasticized SBP–PLA composites exhibited unique AE behavior and confocal microscopy revealed the plasticized SBP and PLA formed a co-continuous two phase system.
V. L. FinkenstadtEmail:
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188.
There is a profound debate over how to assign greenhouse gas (GHG) responsibilities; therefore, we have decided to follow IPCC guidelines, as they offer the only standardized method. We have identified each type of greenhouse emission and its level of absorption. We have studied the province and its districts and municipalities. We have determined that the energy sector is that with the highest level of emissions, even if the per capita emissions of the Province of Siena are very low. This is caused by a very low level of industrialization and the presence of a local geothermal production of energy. In order to highlight this aspect, we have considered scenarios both with and without geothermal production. Our research was then focused on single districts (groups of homogenous municipalities) and municipalities, where we found great differences among the greenhouse emissions of the areas. We have constructed a map of the greenhouse emissions of the whole province. It has been interesting to note that there are 14 municipalities with net negative emissions, seven with low positive emissions, 12 with medium positive emissions and three with elevated positive emissions. These latter correspond to the main city and to two of the most industrialized municipalities.  相似文献   
189.
北方泥炭地是全球重要的碳汇,也是全球变暖最为敏感的区域之一.然而,由于泥炭地表层和亚表层泥炭土碳排放过程对全球变暖的响应过程及机制仍存在一定争议,目前对全球变暖背景下泥炭地碳排放的认识仍存在一定不足.本研究于2019年8月在大兴安岭满归泥炭地采集表层(0~10 cm)和亚表层(15~30 cm)泥炭土进行室内增温模拟有氧培养,测定其矿化速率、有机质性质和水解酶活性.结果表明,表层泥炭土矿化速率在5、15、25℃下培养时((142.8±66.9)~(545.3±30.6)、(575.0±62.1)~(1843.0±547.4)、(888.4±123.9)~(3646.7±167.9)μg·g-1·d-1)均高于亚表层((113.0±41.5)~(367.1±64.1)、(357.4±52.3)~(1122.1±218.8)、(697.1±38.1)~(2336.4±150.6)μg·g-1·d-1),但表层和亚表层矿化作用的温度敏感性不具有显著差异;培养过程中,表层与亚表层泥炭土β-1,4-N-乙酰葡...  相似文献   
190.
新能源汽车替代传统燃油车是减缓能源与环境压力并如期实现“双碳”目标的重要途径,但在重型车辆、工程车等领域推广较为缓慢.深圳市自2019年开始推广使用纯电动泥头车,并计划到2025年新能源环卫、泥头车数量达到8000辆.为深入探究纯电动泥头车替代柴油泥头车所产生的减污降碳协同效益,本研究基于一手调研数据,采用生命周期评价方法并结合GREET模型,对比分析了两类泥头车在燃料周期、车辆周期和配套设施周期3个周期内的能耗、主要空气污染物及碳排放情况.结果表明,纯电动泥头车全生命周期内能耗较柴油泥头车可减少36.2%,主要污染物如NOx、SO2、VOC和PM2.5降幅分别达81.3%、37.8%、29.0%和25.9%;温室气体(GHGs)排放强度减少14.4%,基准情境下2030年和2050年推广纯电动泥头车GHGs累计减排量分别为71.4万t和258.5万t.尽管节能减排效果显著,但其初始购置和售后维保成本过高是制约其推广的最主要因素,通过降低车辆及电池生产制造成本、提高充换电设施数量及售后维保能力等有望加快泥头车纯电动化.  相似文献   
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