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1.
This study investigates the utilization of landfill biogas as a fuel for electrical power generation. Landfills can be regarded as conversion biogas plants to electricity, not only covering internal consumptions of the facility but contributing in the power grid as well. A landfill gas plant consists of a recovery and a production system. The recovery of landfill gas is an area of vital interest since it combines both alternative energy production and reduction of environmental impact through reduction of methane and carbon dioxide, two of the main greenhouse gases emissions. This study follows two main objectives. First, to determine whether active extraction of landfill gas in the examined municipal solid waste sites would produce adequate electric power for utilisation and grid connection and second, to estimate the reduction of sequential greenhouse gases emissions. However, in order to optimize the designing of a plant fed by biogas, it is necessary to quantify biogas production over several years. The investigation results of energy efficiency and environmental impact of biogas utilization in landfills are considering satisfactory enough both in electric energy production and in contribution to greenhouse gases mitigation.  相似文献   

2.
Industrial development has lead to higher energy consumption, emission of greenhouse gases, as well as air pollutants. Cement factories play an important role in over all greenhouse emissions. This study aims to investigate the role of Iranian cement industries and their contribution of greenhouse gases contribution. The measured emission factors for oil and fuel gas shows that carbon dioxide contribution from fuel oil based cement industries is almost 2.7 times higher than gas based cement factories. The strength, weakness, opportunity and threat technique analysis showed that the best strategy to combat greenhouse gases from Iranian cement factory is to implement energy efficiency measures. Further, strategic position and action evaluation matrix analysis indicates that Iranian cement industries fall within invasive category. Therefore, exploitation of opportunities must carefully be used. One of these opportunities is the utilization of financial assistance provided by clean development mechanism. The results show that replacement of ball mills with vertical roller mill can reduce the electricity consumption from 44.6 to 28 kWh/ton. As a result of such substitution about 720 million kWh/y of electricity would be saved (almost a power plant of 125 MW capacities). Though implementation of new mills may not be economic for the cement industries’ owner, but the overall gain for the government of Iran will be about US$ 304 million. If the duration of such efficiency measure is considered as about 12 y, then the overall CO2 reduction/phase-out would be around 4.3 million tons.  相似文献   

3.
煤层气开采对环境的影响   总被引:3,自引:0,他引:3  
煤层气是一种廉价、洁净、高效的新型能源,其开发利用可以弥补常规天然气和燃油的不足,750m^3煤层气可顶替1t标准煤。煤层气开发对环境的影响主要是减少了煤矿甲烷气体的排放,降低温室效应。其负面影响是在钻探、压裂、回注水和提纯过程中会造成煤层和煤层气中杂质气体和有毒有害物质富集,对大气和地下水造成污染。  相似文献   

4.
The technology of anaerobic digestion allows the use of biodegradable waste for energy production by breaking down organic matter through a series of biochemical reactions. Such process generates biogas (productivity of 0.45 Nm3/KgSV), which can be used as energy source in industrial activities or as fuel for automotive vehicles. Anaerobic digestion is an economically viable and environmentally friendly process since it makes possible obtaining clean energy at a low cost and without generating greenhouse gases. Searching for clean energy sources has been the target of scientists worldwide, and this technology has excelled on the basis of efficiency in organic matter conversion into biogas (yield in the range of 0.7–2.0 kWh/m3), considered energy carriers for the future. This paper gives an overview of the technology of anaerobic digestion of food waste, describing the metabolism and microorganisms involved in this process, as well as the operational factors that affect it such as temperature, pH, organic loading, moisture, C/N ratio, and co-digestion. The types of reactors that can be used, the methane production, and the most recent developments in this area are also presented and discussed.  相似文献   

5.
Sasol has been operating the Sasol–Lurgi fixed bed coal gasification process for more than fifty years, and with ninety seven units in operation still remains the world's largest commercial application of this technology. The combined operational and engineering expertise vested in Sasol represents a formidable capability in the field of coal and gasification science. Coal is a crucial feedstock for South Africa's unique synfuels and petrochemicals industry, and is used by Sasol as a feedstock to produce synthesis gas (CO and H2) via the Sasol–Lurgi fixed bed dry bottom gasification process.South Africa, as well as many other countries in the world, will for many years to come rely on its abundant coal resources for energy and specifically for the production of petrochemical products. Synthesis gas production through gasification is growing at a rate of approximately 10% per annum [Office of Fossil Energy, National Energy Technology Laboratory and the Gasification Technologies Council, 2000. Gasification: Worldwide use and acceptance. Contract DE-AMO1-98FE65271], indicating that gasification is definitely not a dying technology. The Sasol plants located in Secunda and Sasolburg (South Africa) gasify > 30 million tons per annum of bituminous coal to synthesis gas, which is converted to fuels and chemicals via the Fischer–Tropsch process. The production of chemicals is currently the dominant application for synthesis gas, followed by power generation, Fischer–Tropsch synthesis and gaseous fuels.Sasol–Lurgi gasifiers are extremely robust devices, and coal from sources with widely varying properties (e.g. ash content < 10% to as high as 35% or “brown coal” with moisture content of approximately 30%) can be gasified provided that certain operational changes are implemented. Other properties, like high caking propensity for example, require blending to acceptable levels and /or mechanical modifications. Interpretation of coal characterization data gives an indication of expected gasifier performance and the suitability of a specific coal source for Sasol–Lurgi Fixed Bed Gasification process. It is therefore critically important to gain an accurate and fundamental understanding of the properties and expected behavior of the targeted coal feedstock in order to (1) prepare a suitable conceptual flow scheme and (2) to maximize the eventual probability of success in any proposed gasification venture and (3) to optimize the operation and profitability of existing plants and (4) effectively address the environmental aspects.It is the view of the authors that fixed bed gasification technology has a bright future in the areas mentioned above and that Sasol has a unique role in the future application and commercialization of gasification technology globally. The unique skills of Sasol could however be complementary to those of other parties who share our view on the future of gasification and related technologies.  相似文献   

6.
中国的温室气体排放、减排措施与对策*   总被引:38,自引:0,他引:38       下载免费PDF全文
黄耀 《第四纪研究》2006,26(5):722-732
根据《中华人民共和国气候变化初始国家信息通报》,1994年中国温室气体排放总量约为3650×106t的CO2当量,其中CO2,CH4和N2O分别占73.1 % ,19.7 % 和7.2 % 。CO2排放主要来自能源活动,CH4排放主要来自农业活动和能源活动,N2O排放主要来自农业活动。在过去的20余年里,中国为减缓全球温室气体排放的增长速度做出了重要的贡献。对文献资料和大量研究结果的分析表明,中国可通过采取相关措施和制订相应政策进一步减少温室气体的排放。减少CO2排放的主要措施和对策包括:调整能源结构(降低煤炭消费比例、适度提高天然气比例和发展核能);提高能源生产、转化、分配和使用过程中的效率;开发利用水能、风能、太阳能和生物能等可再生能源;通过植树造林,推广秸秆还田、平衡施肥和少(免)耕等增加陆地生态系统的碳吸收。减少CH4排放的主要措施和对策包括:回收利用煤层气;改造生活垃圾填埋场地和筛选环境适应性强的CH4氧化菌并接种于填埋场;改善反刍动物的营养成分;稻田合理灌溉、提高水稻的收获指数、选育和种植CH4排放低的水稻品种等。减少农田N2O排放的主要措施和对策包括:提高氮肥利用率;推广施用长效肥和控释肥;施用生物抑制剂和实施微生物工程等。  相似文献   

7.
煤中微量元素研究进展   总被引:30,自引:3,他引:30  
煤炭是我国的主要能源,在煤炭开采、运输、洗选、淋溶(滤)、燃烧等其它加工利用过程中,煤中的微量元素要发生迁移、析出,并入侵到大气、水、土壤和生态环境中,最终影响人类生存和生活环境。煤中微量元素十分重要,是因为它们与环境问题、动、植物及人类健康密切相关。在研究微量元素时必须考虑微量元素的性质及毒性,它们主要依靠其含量、种类、存在形式、pH值、氧化-还原条件及其它因素。在全面综合国内外研究文献的基础上,分析了煤中微量元素的发现、分布规律、赋存状态、成因机理及微量元素的应用等方面研究的历史、现状,并对今后研究的重点内容和发展方向进行了较为详细的论述和分析,并指出在进一步深入研究煤中微量元素地球化学的基础上,加强微量元素环境学方面的研究是今后煤中微量元素环境地球化学研究的重要内容。  相似文献   

8.
Gas drainage not only ensures safety in coal mine but also produces clean energy and reduces emission of greenhouse gases. However, a good method to evaluate the efficiency of gas drainage is still absent. In this study, we firstly propose a definition of gas drainage efficiency which is defined as the ratio of the real output–input efficiency to the ideal output–input efficiency. The definition combines both engineering parameters such as radius, length of borehole and economical parameters such as drilling cost to develop a comprehensive index for the assessment of the engineering–economical efficiency. Then, three important factors to determine gas drainage efficiency including the difficulty level, the input and output, namely investment and production, and the attenuation characteristic of gas drainage are discussed. Based on the relative standards, the index can reasonably evaluate gas drainage projects with different difficulty levels, thereby avoiding dependence on an absolute standard for the evaluation of overall difficulty levels. The indicator can also take both input and output into consideration and reflect the reduction of gas drainage flow with time. Besides, we investigate the relationship between gas drainage efficiency and several engineering parameters, including borehole radius, borehole length and the quality of borehole sealing. The results show the possibility of optimizing engineering parameters to maximize gas drainage efficiency. Finally, the evaluation method is proven efficient by performing case studies.  相似文献   

9.
Drying sewage sludge using flue gas from power plants in China   总被引:1,自引:0,他引:1  
A lot of energy is required for drying the sewage sludge produced during the wastewater treatment process in China; however, on the other hand, the thermal energy in flue gas from power plants is usually wasted as it discharges into the atmosphere. In this study, a new technique for sludge drying is introduced. The key component of the new technique is equipment of a two-stage drying and granulation that utilizes thermal energy contained in the flue gas from power plants and extends sludge contact time with flue gas during the constant-rate evaporation stage. The primary results of the implementation in the Kangshun sludge treatment plant (daily treatment capacity of 100 tons of wet sludge) show that the new drying technique is very effective economically and environmentally. The water content in the sludge was reduced from 78% to less than 30%. The resulted sludge could be used either to co-incinerate with coal in a circulating fluidized bed or to mix with clay to make better bricks. Besides the saving in the direct heating cost in the sludge drying processes by 80%, the saving in fossil fuel consumption due to reuse of the dried sludge is also significant. As a result of the implementation of the new technique in a sludge treatment plant at the scale of the Kangshun plant, about 16,440 tons of CO2 emission could also be reduced every year.  相似文献   

10.
Matching gasification technologies to coal properties   总被引:11,自引:0,他引:11  
The gasification of coal to produce hydrogen for use either in power generation or/and for synthesis applications and transport is attracting considerable interest worldwide. Three types of generic gasifiers (entrained flow, fluidised bed and fixed bed gasifiers) presently in use in commercial gasification plants or under development worldwide are described. Their suitability for processing all types of coals is discussed. This includes an assessment of the impact of some of the major properties of coal on the design, performance and maintenance of gasification processes.  相似文献   

11.
石智军  李泉新 《探矿工程》2016,43(10):150-153,169
我国煤层气资源非常丰富。在煤矿区,煤层气(瓦斯)开发具有增加洁净能源供给、提高煤矿安全生产保障能力、减少温室气体排放等多重效益。地面钻井开发与井下钻孔抽采是煤矿区煤层气(瓦斯)开发的基本途径,同时也是煤矿区应急救援的主要手段。本文介绍了煤矿区地面煤层气开发新技术装备,大直径钻孔施工技术与装备及井下中硬、松软煤层和岩层瓦斯抽采钻孔成孔技术与装备。在此基础上分析了在新形势下煤矿区煤层气(瓦斯)抽采钻孔成孔技术和装备发展需求,为我国煤矿区煤层气(瓦斯)钻孔成孔提供借鉴。  相似文献   

12.
油气地质学的若干问题   总被引:10,自引:0,他引:10  
:2 0世纪世界开采了 115 0亿t石油 ,64万亿m3 天然气 ,如此大量的油气开发是与油气地质的新理论出现并应用于勘探密切相关。 19世纪 70年代出现海相生油论 ,2 0世纪一直在发展和完善 ,其在油气勘探开发中起了重大作用。 2 0世纪 2 0年代开始形成的陆相生油理论 ,对中国石油工业的发展起了重大作用 ,1999年产油 1.60亿t,使中国从“贫油国”而成为世界第五产油大国。2 0世纪 4 0年代煤成气理论形成 ,使勘探天然气理论从仅与腐泥型源岩有关的“一元论” ,发展于既与腐殖型煤系源岩也与腐泥型源岩相关的“二元论” ,促进了天然气工业大发展。世界产气第一大国俄罗斯探明天然气储量 75 %是煤成气 ,中国近期天然气储量大幅度增长是以煤成气为支撑的 ,2 0 0 0年全国气层气储层的 64%是煤成气。天然气水合物是非常规气 ,较一致估计资源量在 2 .0×10 16 2 .1× 10 16 m3 ,相当于当前已探明的化石燃料总含碳量的 2倍 ,被认为可能是 2 1世纪的替代能源 ,潜力大。但由于地质的、成藏的、富集的、开发的和环境的诸多问题未深入研究或有待解决 ,目前未开发利用。  相似文献   

13.
煤基碳排放构成了中国碳排放总量中最重要的部分,做好煤基碳减排和煤炭高效洁净低碳化利用是实现“碳中和”国家目标的重要途径,碳中和背景下的煤地质学发展值得关注。系统评述与碳中和相关的煤地质学研究领域,分析煤地质学在碳中和研究与工程实践中的作用和应用前景,探讨碳中和背景下煤地质学的重要发展方向。取得以下认识:推进清洁煤地质研究、服务煤的高效洁净化燃烧,勘探开发煤系天然气低碳燃料、优化一次能源结构和化石能源结构,开展煤化工资源勘查与开发地质保障研究、推动煤炭的低碳能源转化和新型煤化工产业发展,深化瓦斯地质研究、提高煤矿瓦斯(井下)抽采率、控制煤矿瓦斯的大气排放和泄漏,研究煤层甲烷天然逸散和煤层自燃排放、控制煤层露头的天然排放,发展煤层CO2地质封存与煤层气强化开发(CO2-ECBM)技术、推动碳捕获、利用与封存(CCUS)技术发展及其在火力电厂烟气碳减排中的商业化应用,研究煤炭勘查企业的碳足迹、实现企业净零排放,是与煤地质学紧密相关的碳减排技术路径;其中煤层甲烷与煤系气高效勘探开发、深部煤层CO2-ECBM、煤层露头气体逸散与自燃发火控制、洁净煤地质与煤炭精细勘查是碳中和背景下煤地质学优先发展的重要领域。   相似文献   

14.
洁净煤技术应用现状综述   总被引:4,自引:1,他引:4  
我国是煤炭生产和消费大国 ,大力开发应用适合我国国情的煤炭地下气化技术、工业型煤技术、水煤浆气化技术、煤液化技术、洁净煤联合循环发电技术、煤系废弃物的综合利用技术等洁净煤技术 ,对提高煤炭利用率 ,改善环境状况 ,实现能源工业 (也包括化工及其它相关行业 )的可持续发展 ,有重要意义并具有广阔的发展前景。  相似文献   

15.
《Comptes Rendus Geoscience》2003,335(6-7):611-625
Increasing atmospheric level of greenhouse gases are causing global warming and putting at risk the global climate system. The main anthropogenic greenhouse gas is CO2. Technical solutions exist to reduce CO2 emission and stabilise atmospheric CO2 concentration, including energy saving and energy efficiency, switch to lower carbon content fuels like natural gas and to energy sources that operate with zero CO2 emissions such as renewable or nuclear energy, enhance the natural sinks for CO2 (forests, soils, etc.), and last but not least, sequester CO2 from fossil fuels combustion. The purpose of this paper is to provide an overview of the technology and cost for capture and storage of CO2. Some of the factors that will influence application, including environmental impact, cost and efficiency, are also discussed. Capturing CO2 and storing it in underground geological reservoirs appears as the best environmentally acceptable option. It can be done with existing technology; however, substantial R&D is needed to improve available technology and to lower the cost. Applicable to large CO2 emitting industrial facilities such as power plants, cement factories, steel industry, etc., which amount to more than 30% of the global anthropogenic CO2 emission, it represents a valuable tool in the battle against global warming. To cite this article: P. Jean-Baptiste, R. Ducroux, C. R. Geoscience 335 (2003).  相似文献   

16.
《Applied Geochemistry》2006,21(11):1821-1836
The proportion of Hg in coal feedstock that is emitted by stack gases of utility power stations is a complex function of coal chemistry and properties, combustion conditions, and the positioning and type of air pollution control devices employed. Mercury in bituminous coal is found primarily within Fe-sulfides, whereas lower rank coal tends to have a greater proportion of organic-bound Hg. Preparation of bituminous coal to reduce S generally reduces input Hg relative to in-ground concentrations, but the amount of this reduction varies according to the fraction of Hg in sulfides and the efficiency of sulfide removal. The mode of occurrence of Hg in coal does not directly affect the speciation of Hg in the combustion flue gas. However, other constituents in the coal, notably Cl and S, and the combustion characteristics of the coal, influence the species of Hg that are formed in the flue gas and enter air pollution control devices. The formation of gaseous oxidized Hg or particulate-bound Hg occurs post-combustion; these forms of Hg can be in part captured in the air pollution control devices that exist on coal-fired boilers, without modification. For a given coal type, the capture efficiency of Hg by pollution control systems varies according to type of device and the conditions of its deployment. For bituminous coal, on average, more than 60% of Hg in flue gas is captured by fabric filter (FF) and flue-gas desulfurization (FGD) systems. Key variables affecting performance for Hg control include Cl and S content of the coal, the positioning (hot side vs. cold side) of the system, and the amount of unburned C in coal ash. Knowledge of coal quality parameters and their effect on the performance of air pollution control devices allows optimization of Hg capture co-benefit.  相似文献   

17.
Resource scheduling for both cost and pollution minimization in the power system is so crucial. To reduce the greenhouse gas emission, employing renewable energy resources, especially solar and wind energy, and beside them plug-in hybrid electric vehicles are effective solutions. In industrial factories, using biomass resources for power generation is both economic and environmental approach. In sugarcane company, bagasse is plant fiber residue which is used as fuel. Electric lift trucks, capable of being connected to power grid, could decrease the pollution in industrial transportations. In this paper, scheduling problem for a large-scale sugarcane factory including solar resources, a thermal unit, and electric lift trucks is presented and solved by CPLEX solver in GAMS software. In order to consider uncertainties, different scenarios are noticed. To contribute better understanding of optimization problem, cost, pollution, and charging regime of electric lift trucks are carefully analyzed. The results show that implementation of the biomass electric power generation is effective for reducing cost and amount of emission.  相似文献   

18.
The importance of mitigation of climate change due to greenhouse gas (GHG) emissions from various developmental and infrastructure projects has generated interest at global level to reduce environmental impacts. Life cycle assessment may be used as a tool to assess GHG emissions and subsequent environmental impacts resulting from electricity generation from thermal power plants. This study uses life cycle approach for assessing GHG emissions and their impacts due to natural gas combined cycle (NGCC) and imported coal thermal power plants using the IPCC 2001 and Eco-Indicator 99(H) methods in India for the first time. The total GHG emission from the NGCC thermal power plant was 584 g CO2 eq/kWh electricity generation, whereas in case of imported coal, it was 1,127 g CO2 eq/kWh electricity generation. This shows that imported coal has nearly ~2 times more impacts when compared to natural gas in terms of global warming potential and human health as disability-adjusted life years from climate change due to GHG emissions such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O).  相似文献   

19.
热开采法、抑制剂刺激法等传统天然气水合物开采方法将破坏水合物地层,不能有效地解决海底地层破坏和开采使用化石燃料燃烧后所存在的碳储存和碳捕捉问题.介绍了低温固体氧化物燃料电池法开采天然气水合物的方法.该方法利用CO2置换天然气水合物地层中的甲烷,运送到低温固体氧化物燃料电池的阳极,在阴极通入空气,发生电化学反应,产生电能,并将产出的CO2通入到天然气水合物地层,置换出甲烷.该方法简单、实用,克服了传统开采方法所存在的问题,发电效率较传统发电方法大幅提高.  相似文献   

20.
天然气水合物是一种新型的清洁能源矿产资源,据估算其资源量是全球煤炭、石油、天然气资源总量的两倍。青藏高原北部祁连山木里煤田天然气水合物的发现,是我国天然气水合物研究的重大突破。基于煤炭地质勘查工作及其相关研究成果,采用煤炭总量理论产气量法、天然气水合物体积法、天然气水合物稳定带体积法等三种方法,首次估算了木里煤田天然气水合物的潜在资源量,这对于评价该区天然气水合物资源前景具有重要意义。  相似文献   

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