基于双流化床(DFBB)燃烧的锅炉烟气超低排放技术

现有燃煤电厂、燃煤锅炉超低排放技术主要是末端治理,本文介绍了依据煤炭在循环流化床锅炉燃烧过程中N、S的迁移机理,结合循环流化床和鼓泡流化床的技术特点,研发的双流化床锅炉及其高效洁净燃烧技术工艺,从源头控制、实现燃煤电厂及燃煤锅炉二氧化硫、氮氧化物"超低排放"的技术路线及其优势。     

应对超低排放上海火电环保设施协同改造的研究与实践

介绍了上海火电控制燃煤机组建设、节能降耗、"强馈入、弱开机"、控制燃煤质量等措施从源头上降低了污染排放,分析了采用先进的环保技术和治理设备所取得显著的环保效果,阐述了环保排放状况和各类机组污染排放特性,并列举了燃煤电厂对烟气污染控制设备进行协同改造的成功案例,可为其他机组的超低排放改造提供依据和借鉴。     

煤种变化对燃煤电厂综合经济性影响分析

随着电力体制改革的持续深化,燃煤电厂的经营模式已由计划经济转向市场经济,发电厂不得不面对"市场煤"与"计划电"的严峻挑战,燃料成本已成为影响电厂经济性的关键因素。以山西南部某发电厂为研究对象,通过多煤种、多工况试验,定量地分析了煤种变化对锅炉效率、排灰成本、环保成本、检修费用等指标的综合影响,提出用综合标煤单价来全面衡量燃煤的经济性,使燃煤由定性分析变为定量管理,实现燃煤管理的新突破。对燃煤电厂的经营决策、成本分析、燃料管理具有一定的借鉴作用,并能推动企业降低发电成本、提高经济效益。     

亚临界燃煤机组AGC控制策略优化分析

为提高燃煤机组自动发电控制(AGC)控制质量,满足华东电网对电厂的技术要求,主要分析了亚临界火电燃煤机组AGC负荷控制响应滞后问题,并结合华能太仓电厂2号机组300 MW亚临界火电机组的AGC控制逻辑情况,总结出改善机组AGC控制质量的变负荷前馈优化方案,并通过理论分析,设计了预加煤微分逻辑、限幅逻辑、煤量修正及速率限制逻辑、一次风压修正逻辑等手段进行控制优化,并对锅炉侧的滞后性、安全性进行了优化,提高了机组AGC控制品质。     

燃煤电厂氮氧化物控制技术探究

燃煤电厂是氮氧化物(NO_X)排放的主要污染源之一。文章阐述了NO_X的生成及脱除机制,详细介绍了当前燃煤电厂主要的NO_X控制技术,深入分析了多种NO_X控制技术的适用范围、技术可行性等各方面内容,提出了多种NO_X控制技术的优化组合方案,对燃煤电厂NO_X控制技术提供一定的指导参考。     

燃煤电厂入厂煤度电碳排放分析研究

为探究燃煤电厂采购煤之间的碳排放的差异性,合理制定相应的采购计划,以某燃煤电厂入厂煤为研究对象,通过定量分析得到各采购煤种的单位度电碳排放强度,并给出合理的采购建议,从源头上控制机组二氧化碳的排放,为电厂燃煤采购提供依据。     

基于CFB机组的超低排放及多污染物协同脱除装备应用

燃煤电厂烟气中所含的烟尘、二氧化硫和氮氧化物是我国污染防治攻坚战工作的重点。在实现超低排放后,燃煤烟气中所携带剧毒性物质汞以及三氧化硫在大气中形成亚微米级的硫酸盐颗粒,也必将成为燃煤电厂重点控制污染物。文中以某电厂CFB机组为例,在发挥循环流化床洁净燃烧的基础上,有机集成应用了"炉内脱硫脱硝+SNCR+干式超净工艺"的超低排放装备,实现了二氧化硫、氮氧化物、烟尘排放浓度优于超低排放标准,并高效协同脱除汞和三氧化硫等多污染物,无脱硫废水产生。     

国内外燃煤电厂二恶英排放及控制

原煤中二恶英含量极低,主要为煤燃烧过程中产生.对国内外燃煤电厂排放烟气和灰渣中二恶英排放情况进行调研,结果显示,火电行业二恶英大气和灰渣(飞灰、底灰、炉渣、烟尘和脱硫废物)排放状况相差较大,其大气排放质量浓度范围为0.365～1 400 pgI-TEQ/m~3,大气排放因子为0.002 04～6.2μgI-TEQ/t煤,灰渣中PCDD/Fs质量分数为0.02～52.6 ngI-TEQ/kg灰.通过火电企业大气和灰渣排放量,以及耗煤量,可得到大多数国家或地区燃煤电厂大气PCDD/Fs排放量为0～95 g I-TEQ/a范围,灰渣PCDD/Fs排放量也能达到相当的程度,燃煤电厂排放二恶英应引起关注.通过分析燃煤电厂PCDD/Fs生成条件,提出控制二恶英生成的策略.本研究对我国履行斯德哥尔摩公约(POPs公约),制定燃煤电厂二恶英排放标准和提高控制能力提供基础.     

生物质燃煤耦合发电技术应用现状及未来趋势

国务院"十三五"提出控制温室气体排放目标后,如何较大幅度地降低CO2排放成为燃煤电厂面临的巨大挑战之一。按照现有的煤电技术,仅通过提高煤电效率降低煤耗和CO2排放强度是非常困难的。燃煤电厂采用生物质与煤电耦合发电技术,是当前最可行的降低碳排放的措施。文章针对生物质替代煤炭发电应用的现状,介绍了现阶段燃煤耦合生物质发电的几种方式,及其在现有电厂中的应用情况,并简要分析其优缺点。结合耦合技术自身特性、经济成本及中国国情,提出生物质气化耦合发电是未来的发展趋势。     

SCR脱硝反应器入口导流板设计优化分析

随着我国对NOx排放标准的不断提高,单纯依靠燃烧过程控制已不能满足国家标准要求,因此国家也相应出台了一系列控制燃煤电厂NOx排放的法律、法规和政策,促使我国加快燃煤电厂烟气脱硝装置的建设。SCR脱硝技术具有脱硝效率高、运行可靠等优点,已得到了广泛应用。文中主要介绍燃煤电厂SCR脱硝反应器入口导流板对SCR脱硝反应器流场的优化作用及入口导流板设计优化分析,对SCR脱硝反应器入口导流板的设计原则及优化分析等进行了一定的阐述。     

Steam versus coking coal and the acid rain program

The Clean Air Act of 1990 initiated a tradable permit program for emissions of sulfur dioxide from coal-fired power plants. One effect of this policy was a large increase in the consumption of low-sulfur bituminous coal by coal-fired power plants. However, low-sulfur bituminous coal is also the ideal coking coal for steel production. The analysis presented here will attempt to determine how the market responded to the increased consumption of low-sulfur bituminous coal by the electricity generation sector. Was there a decrease in the quality and/or quantity of coking coal consumption or did extraction increase? Most evidence suggests that the market for coking coal was unaffected, even as the extraction and consumption of low-sulfur bituminous coal for electricity generation increased substantially.     

Unified efficiency measurement of coal-fired power plants in China considering group heterogeneity and technological gaps

China's coal-fired power generation has accounted for a large proportion of the power supply for a long time and the resulting environmental pollution and waste of resources have hindered the sustainable development of the power industry. To solve this problem, this study combines the concept of natural and managerial disposability with the non-concave meta-frontier method to determine the unified efficiency measurement of 251 coal-fired power plants in China from 2012 to 2014 and to investigate the sources of inefficiency in different areas. The results show that although the unified efficiency of China's coal-fired power plants improved significantly during 2012–2014, much room for improvement remains in terms of power generation and environmental performance. Due to the advanced technology of coal-fired power plants, the eastern area has the highest unified efficiency in terms of natural and managerial disposability. The western region has the lowest operational performance and the northeast region has the lowest environmental performance. The decomposition of the sources of inefficiency indicates that the inefficiency of coal-fired power plants in eastern China is mainly caused by management factors, whereas the inefficiency in northeastern China is due to a lag in technology. In the central and western areas, technical inefficiency and management inefficiency both account for a considerable proportion in their sources of inefficiency. Therefore, these regions need to improve both the management (e.g., reasonable allocation of utilization hours) and technology (e.g., clean coal technology) aspects to improve the unified performance of coal-fired power plants.     

煤质变化对CFB锅炉运行的影响

结合当前市场煤质特点,分析了电厂燃煤发热量、粒度、灰份、挥发份对CFB锅炉运行造成的影响,从提高运行操作水平,加强煤质管理方面提出建议,保障了CFB锅炉的正常运行。     

Prediction for the burnout of pulverized coal in a coal-fired power plant by combining proximate analysis,coal petrography,and pulverized-coal size distribution

Highly changeable coal quality, low combustion efficiency, and huge consumption of coal are the three common problems facing most of China’s coal-fired power plants. Proper prediction for the coal burnout in power boilers has important economic and environmental significance. By combining critical factors in proximate analysis, coal petrography, and the size distribution of pulverized coal, this article aims to propose a comprehensive method to predict the burnout of pulverized coal in power boilers. Results show that: (a) volatile content and calorific value are the two most important factors in proximate analysis, (b) the most important factors in coal petrography are the relative content of reactive and unreactive macerals and the mean and standard deviation of vitrinite reflectance, and (c) the 90–200-μm-size fraction is a particularly important factor in the size distribution of pulverized coal. Compared with any parameters or indices based on one of the three aspects in proximate analysis, coal petrography, and pulverized-coal size distribution, the synthetic index into which these critical factors are combined has a better significant correlation with coal burnout.     

我国防止雾霾污染的对策与建议

一般认为煤炭和石油对雾霾的贡献最大,尤其是燃煤电厂,因为煤炭占我国能源消费量的90％,燃煤电厂约占煤炭消费量的50％.我国防止雾霾污染的对策应基于:解决气候变化与环境保护问题,要靠发展非化石能源毕其功于一役是难以办到的,我们应像发达国家那样,先解决好化石能源利用中的环境问题,然后再解决化石能源利用中的气候变化问题.电力是最能清洁利用煤炭的部门,我国燃煤电厂的烟尘和二氧化硫控制已达到世界先进水平,已不是形成雾霾的主要原因.短期内应对雾霾气候的措施为:下决心解决好大气、水、土壤污染;控制大气污染要把控制PM2.5放在重要位置;天然气要优先用于替代分散的燃煤部门,并把替代下来的煤炭交给煤电厂应用;如果我国煤炭消费量中的80％～90％的煤炭供燃煤电厂用,就可控制燃煤污染.燃煤电厂对降低燃煤污染物排放负有重要责任.     

曲线落煤管及无动力除尘导料槽使用展望

针对燃煤电厂输煤系统传统转运站设计存在的粉尘大、落煤管堵煤等问题,介绍了一种曲线落煤管及无动力除尘导料槽组合的新型转运站设计。该落煤管设计通过对物料的汇集,实现了运输物料的可控化,从而降低落煤管堵煤现象的发生,减少对下游皮带的冲击。通过与无动力除尘导料槽组合达到控制诱导风,降低粉尘浓度。     

中国中长期碳减排战略目标初探(Ⅱ)——中国煤炭消费过程的碳排放及减排措施

中国能源领域排放的二氧化碳主要来自煤炭,因此煤炭消费过程中的碳减排措施尤为重要。煤炭的主要用户是发电部门,基于应对气候变化的需要,煤电行业的低碳途径不得不考虑采用CCS技术。不论是新建燃煤电厂,还是今后在传统电厂改建过程中增设CCS设施已是大势所趋,预计多数仍将采用MEA法脱除烟气中二氧化碳这一成熟技术。由于MEA法技术经济指标不够先进,估计10~20年内必将出现更先进的脱二氧化碳工艺技术。传统的燃煤锅炉增加CCS的经济效益已经逊于IGCC-CCS,预计2020年后IGCC电厂将成为新建煤电厂的首选方案。20年后采用临氢气化炉与燃料电池FC发电相结合、把高温的热能和甲烷的化学能直接转化为电力的IGFC高效燃煤电厂或将成功应用,IGFC综合能量转化效率比IGCC相对高出1/2~3/4,发展前景不可低估。钢铁、水泥和化工等高耗煤工业部门可通过节能和采用CCS技术降低碳排放,其余用煤的工业部门和分散用户则应考虑节能或用天然气等低碳燃料替代,间接起到减排效果。预计2050年燃煤发电和高耗煤工业总计将排放二氧化碳4.6Gt,如果二氧化碳捕集量是2.9Gt,则净排放量为1.7Gt。加上其他难以捕集二氧化碳的工业、部门及民用煤排放二氧化碳1.0Gt,合计二氧化碳净排放量为2.7Gt(情景A)。如果采用更先进的技术和严格的节能减排措施,可减少煤炭消耗0.31Gt标煤,减少二氧化碳排放0.5Gt,使煤源二氧化碳净排放量减少到2.2Gt(情景B)。无论哪种情景,实施CCS的任务都十分艰巨。     

Research and Development of Supercritical Carbon Dioxide Coal-Fired Power Systems

Using supercritical carbon dioxide(S-CO2)Brayton cycle instead of the traditional steam Rankine cycle is a promising technique to enhance the coal-fired power generation efficiency.Researchers from all over the world are actively designing and exploring efficient S-CO2 coal-fired power plants in recent years with great efforts made to overcome the significant technical challenges in the cycle layouts of S-CO2 and its specific thermal integration with coal-fired heat resources.This paper provides a detailed review of the research progress on the coal-fired power generation using S-CO2 Brayton cycles.The basic knowledge of S-CO2 properties,the promising S-CO2 power cycles and the conceptual designs for S-CO2 coal-fired power plants are comprehensively summarized,with some key issues in the constructing process and the corresponding engineering solutions being emphatically discussed.Based on the current achievements,the overall technical and economic evaluations on the S-CO2 coal-fired power system are figured out.Furthermore,the specific integration applications of S-CO2 cycles with different coal firing devices and modes including pulverized coal combustion,circulating fluidized bed combustion,oxy-coal combustion,pressurized fluidized bed combustion,chemical looping combustion are discussed.Finally,the main challenges requiring further studies are highlighted.     

Development of a new solar,gasification and fuel cell based integrated plant

Despite its shortcomings, fossil-based fuels are still utilized as the main energy source, accounting for about 80% of the world's total energy supply with about one-third of which comes from coal. However, conventional coal-fired power plants emit relatively higher amounts of greenhouse gases, and the derivatives of air pollutants, which necessitates the integration of environmentally benign technologies into the conventional power plants. In the current study, a H₂–CO synthesis gas fueled solid oxide fuel cell (SOFC) is integrated to the coal-fired combined cycle along with a concentrated solar energy system for the purpose of promoting the cleaner energy applications in the fossil fuel-based power plants. The underlying motivation of the present study is to propose a novel design for a conventional coal-fired combined cycle without altering its main infrastructure to make its environmentally hazardous nature more ecofriendly. The proposed SOFC integrated coal-fired combined cycle is modeled thermodynamically for different types of coals, namely pet coke, Powder River Basin (PRB) coal, lignite and anthracite using the Engineering Equation Solver (EES) and the Ebsilon software packages. The current results show that the designed hybrid energy system provide higher performance with higher energy and exergy efficiencies ranging from 70.6% to 72.7% energetically and from 35.5% to 43.8% exergetically. In addition, carbon dioxide emissions are reduced varying between 18.31 kg/s and 30.09 kg/s depending on the selected coal type, under the assumption of 10 kg per second fuel inlet.