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《动力工程学报》2017,(4):321-328
以某600MW超超临界燃烟煤机组为对比机组,对常规低温省煤器、低温省煤器前移和旁通烟道3种锅炉尾部烟气余热利用系统进行了热经济性与技术经济性比较.结果表明:回收锅炉排烟由122℃降温至90℃的余热,3种系统可使机组供电标准煤耗分别减小1.51g/(kW·h)、1.71g/(kW·h)和2.81g/(kW·h),需分别投资1 125万元、1 940万元和1 685万元,动态投资回收期分别为4.42a、8.66a和3.29a;低温省煤器前移对机组供电效率的提高不明显,但因应用水媒式空气预热器,受热面投资显著增大,因而技术经济性欠佳;由于节能效果显著,旁通烟道表现出最优的热经济性和技术经济性,建议对其进一步研究和推广应用. 相似文献
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《动力工程学报》2017,(9)
针对我国西北地区太阳能和低阶煤资源丰富的特点,提出一种利用太阳能预干燥低阶煤的发电系统.以某典型600 MW超临界机组为例,通过建立太阳能集热单元和低阶煤预干燥单元的热平衡模型,分析了太阳能预干燥低阶煤后煤的质量与能量的变化规律,从机组煤耗率和太阳能光电转换效率等角度评估了太阳能预干燥低阶煤发电系统的综合热力性能;并以静态投资回收期作为经济性评价指标,探讨了设备总投资和上网电价变化对机组经济性能的影响.结果表明:利用低品位太阳能预干燥低阶煤可有效降低机组煤耗率,当低阶煤水分由25.0%干燥至10.0%时,煤耗率降低8.9g/(kW·h),同时太阳能光电转换效率可达到25.3%,静态投资回收期仅为4.3a,系统经济效益显著. 相似文献
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《汽轮机技术》2021,63(3)
介绍了"低压光轴供热技术"的工作原理和改造方案,并对某电厂200MW机组采用"低压光轴供热技术"改造后的调峰能力及经济性进行了分析。结果表明:"低压光轴供热技术"改造后,机组带工业抽汽50t/h,额定工况下发电负荷为148.39MW,机组不带工业抽汽,额定工况下发电负荷为153.35MW;在相同的主蒸汽流量(659.7t/h)下,单机供热负荷增加了136.5MW,单机供热能力增加了64.35%,单机发电煤耗降低了90.9g/(kW·h);改造前全年机组平均发电煤耗约285.1g/(kW·h),改造后全年机组平均发电煤耗约263.22g/(kW·h),全年机组平均发电煤耗下降约21.88g/(kW·h)。可见,通过"低压光轴供热技术"改造后,可大幅提高机组的调峰能力和供热能力,经济效益显著,该技术具有广阔的推广应用前景。 相似文献
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本文通过对燃机配余热制冷机组的天然气热电冷三联产系统能量模型和经济模型的建立,分析了系统发电效率、热电综合效率、电价、天然气价格、单位千瓦燃机造价对系统年净收益和静态投资回收期的影响.得出当发电效率在24%~30%,热电综合效率在60%~77%,电价在0.6~0.87元/kWh之间,天然气价格小于2元/m3,单位千瓦燃机造价不大于800元/kW时,项目投资可在4.5年内回收,经济效益良好. 相似文献
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为了探讨0号高压加热器和外置蒸汽冷却器在不同布置方式、不同负荷和不同外置蒸汽冷却器给水质量流量下的节能效果,利用Ebsilon软件对某660 MW机组进行分析。结果表明:当系统增设0号高压加热器时,75%THA和50%THA负荷下,给水温度分别提高23.2 K和21 K,热耗分别降低约31.2 kJ/(kW·h)和35.8 kJ/(kW·h);当利用三抽蒸汽过热度加热给水时,进入省煤器的给水温度可提升约3.2 K,100%THA、75%THA和50%THA负荷下的热耗分别降低10.7 kJ/(kW·h)、10.8 kJ/(kW·h)和13.7 kJ/(kW·h);同时增设0号高压加热器和外置蒸汽冷却器时,在75%THA和50%THA负荷下,热耗分别降低约40.6 kJ/(kW·h)和48.2 kJ/(kW·h),机组在低负荷下经济性有所提高。 相似文献
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《汽轮机技术》2019,(6)
针对某200MW供热机组,通过分析两种低压通流改造方案的技术特征与改造内容,确定了最优改造方案,给出了汽轮机及热网系统的改造技术方案,并对改造前后机组采暖热负荷和性能指标进行对比分析。分析得出采用低压通流部分改造方案更有利于该机组供热节能升级改造,降低投资和运行维护成本。1号机组改造后,全厂的供热能力和发电出力均有提高,节能效果显著。改造后,1号机组供热能力由94MW增至281.6MW,增加了187.6MW;发电煤耗率由改造前的269.2g/(kW·h)降至138.9g/(kW·h),降低了130.3g/(kW·h),全厂年节约标煤量为70 920t。 相似文献
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采用APROS软件建立了PG9171E型燃气—蒸汽联合循环机组系统仿真模型,分析底循环系统高压蒸汽压力、高、低压蒸汽温度、凝汽器排汽压力对联合循环机组经济性的影响。研究表明:提高蒸汽参数,机组热耗率下降;高压蒸汽压力与机组热耗率近似呈二次函数关系;额定负荷工况下,高压蒸汽温度上升1℃,机组热耗率下降约2.57 kJ/(kW·h);而低压蒸汽温度上升1℃,机组热耗率下降约0.40 kJ/(kW·h);降低凝汽器排汽压力,有利于提高联合循环机组的经济性,但需协调考虑末级叶片运行的安全性和联合循环机组的经济性。 相似文献
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以某电厂650 MW超临界机组为研究对象,针对机组传统供热改造后"以热定电"调峰灵活性较差的运行问题,提出了"低压缸零出力技术"的工作原理和提高机组热电解耦能力的改造方案,并分析了"低压缸零出力技术"改造后的灵活性调峰能力及经济性。结果表明:额定工况发电负荷由改造前的458.6 MW降至353.3 MW;额定工况供热负荷由改造前的540.6 MW增加至821.95 MW;额定工况发电煤耗由改造前的238.2 g/(kW·h)降至201.7 g/(kW·h),可大幅提高机组的灵活性调峰能力和供热能力,经济效益显著。 相似文献
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The balance between the demand for electricity by consumers and businesses, and environmental protection, is one of the key challenges of our society.The PV industry in 2010 compared to 2009 registered a growth of 130%, consolidating the previous achievements. The reduction in costs of system and incentive policies have favored the development of solar energy.At the same time, the results achieved have led to a resulting reduction of Feed-in Tariff (FiT) by the central governments, generating concern from both the owners, investors and operators.This article belongs to a wider research and aims to analyze the determinants of investment risk in the PV industry through a sensitivity analysis, scenario analysis and risk analysis. To do this, alternative business plans have been developed that compared to the static situation, allow to quantify how Net Present Value varies according to different parameters. Strong attention is placed on the project's critical variables, the opportunity cost of capital, the time duration of the project, the plant size and geographical location of the system, analyzing the specific case of Italy. 相似文献
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《Energy Policy》2013
This paper presents an alternative decomposition method to explore the driving forces of change in carbon emissions by using distance functions estimated by data envelopment analysis. The proposed approach can isolate the effects of changes in GDP composition and energy supply composition on the change of carbon emissions. In addition, it is capable of identifying the effects of changes in different input ratios, which may be very important if there are substitution effects among different inputs. Moreover, the proposed model can measure the effects of changes in good and bad output technical efficiencies. Consequently, this decomposition technique allows a change of carbon emissions to be decomposed into contributions from ten factors, which provides more insights for policy makers. We apply this model to decompose carbon emissions in 25 OECD counties and China. For the sample countries as a whole, the empirical results indicate that the economic growth is the crucial driver to carbon emissions increase, while the changes in GDP composition and capital–energy ratio are two main drivers to carbon emissions reduction. In particular, we discuss in detail the driving forces of China's carbon emissions change in order to propose some valuable policy implications for China from an international perspective. 相似文献
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根据广西岩溶区澄碧河流域1963~2014年逐日降水资料,结合百分位计算法定义极端降水阈值,在此基础上,采用线性趋势、Mann-Kendall、Morlet小波分析及Pearson相关系数等方法分析了极端降水指数演变规律及其与年径流的关系。结果表明,极端降水量、极端降水日数和极端降水比率呈上升趋势,10年上升率分别为2.3mm、0.034d、0.7%,极端降水强度呈下降趋势,下降率为-0.02mm/(d·10a),经Mann-Kendall趋势检验,上升和下降趋势均不显著;经过多种突变检验法综合诊断,极端降水量和极端降水强度的突变年份为2009年,极端降水日数和极端降水比率的突变年份为1976年;各极端降水指数周期演变特征基本一致,第一、二主周期分别为28、15年,且丰枯交替明显;极端降水量与年径流的相关性最强,极端降水强度与年径流的相关性最弱。 相似文献
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Selçuk Bilgen 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(22):3324-3331
Coal as an energy source is vital for developing industries. Chemical analysis of coal becomes necessary to identify its properties and to minimize its negative environmental effects because these countries are obligated to use an environmentally friendly coal. This paper aims to supply information for a more universal coal evaluation and this information will surely support research on new coal technologies and help to solve the environmental problems yielded by coal consumption. Information in the current study is useful for an engineer to know and understand before attempting selection and design of an industrial process that use coal. 相似文献
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Valter Luiz Jantara Junior Mayorkinos Papaelias 《International Journal of Hydrogen Energy》2021,46(17):10468-10477
This paper explores the potential of hydrogen as an energy carrier for deep-sea applications. Finite element analysis of a type III pressurised cylinder to the intended working pressures of 300 bar internal and up to 600 bar external were carried out for different designs and safety factors. Design parameters such as helical angle, liner, helical, and hoop thicknesses were studied and optimised. A buckling analysis was carried out for the optimised designs and recommendations to increase the maximum allowable external pressure are given. 相似文献
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对"十一五"期间在我国核心期刊上发表的太阳能专业科技论文进行了统计与分析。从论文发表的年代、数量、发表机构、专业内容、技术主题和热点等方面,探讨了我国太阳能利用技术的研究现状、存在问题及发展趋势,对我国太阳能利用技术发展现状给予了客观评价,提出了关于我国太阳能利用技术发展的建议。 相似文献