燃气蒸汽联合循环余热锅炉能效分析的矩阵模型

燃气蒸汽联合循环机组作为一种环保性好、效率高、调峰性好的机组已成为我国发电机组中不可或缺的组成部分,在未来仍有很大的发展潜力。但是,目前针对于燃气——蒸汽联合循环电站的热经济性分析一般只使用常规热平衡法和火用分析方法两种方法。而本文中使用了矩阵分析法,导出了三压再热型的燃气——蒸汽联合循环机组热力系统分析计算方法。此方法物理意义明确且通用性为强,数据易处理,结果易分析。为进一步用矩阵理论研究燃气——蒸汽联合循环机组的节能降耗奠定了基础。     

考虑环境因素的燃气-蒸汽联合循环能耗特性分析

燃气-蒸汽联合循环机组具有较高的效率和环保特性,是发电领域的热点之一。联合循环的能耗特性会随环境条件和负荷条件变化而变化。考虑环境条件变化的燃气-蒸汽联合循环的机组变工况特性研究具有一定的理论意义和实用价值。分析研究燃气-蒸汽联合循环主要设备特性,采用差分进化法,结合某燃气-蒸汽联合循环6F发电机组的运行数据和设计数据对联合循环进行建模,挖掘出燃气-蒸汽联合循环中各参数之间的关系,进而得到燃气-蒸汽联合循环能耗随环境温度变化的规律,这对优化燃气-蒸汽联合循环性能具有重要意义。     

基于灯用分析的燃气-蒸汽联合循环机组变工况研究

以华东地区某200 MW燃气-蒸汽联合循环机组为例,建立了燃气-蒸汽联合循环机组的用分析数学模型,通过APROS仿真模型获得机组改变工况参数,分析了燃机负荷、环境温度及供热抽汽量对系统各部件及全厂用损失和用效率的影响。研究表明:燃烧室的用损失远大于其他部件,而凝结水泵的用损失则为最小;燃机负荷对联合循环用损失和用效率的影响较大,并随着燃机负荷的上升,燃烧室用效率明显增大,使得全厂用效率也有所提高。当环境温度上升,燃气透平的用损失也明显上升,但其所占全厂用损失的比例不高,其余部件的用损失均变化不大,因此,全厂用效率随着环境温度的上升稍有降低;燃气机组用效率的变化决定了全厂用效率的变化趋势,而联合循环机组热电联产可有效提高企业机组的运行经济性。     

燃汽-蒸汽联合循环灵活性分析

新能源的快速发展冲击了电网的稳定性,也对火力发电机组的调峰调频能力提出了更高的要求。考虑到燃气-蒸汽联合循环机组具有热效率高、启停快、易于调峰等特性,使用燃气-蒸汽联合循环进行调峰调频是理想的选择。介绍燃气-蒸汽联合循环的工作方式和结构特性,比较不同的联合循环的优缺点,讨论联合循环机组在变工况运行时影响其效率的因素,并对某燃气热力电厂的不同运行工况进行了热力性质计算,对循环机组的变工况特性进行直观分析。分析得出,低负荷运行工况下,燃气-蒸汽联合循环的热效率随着负荷下降而呈现加快升高趋势,经济性很低,不宜长期运行。     

保证燃气-蒸汽联合循环余热锅炉性能的措施

从燃气-蒸汽联合循环余热锅炉的设计出发,根据影响余热锅炉性能的各种因素,简要分析说明了保证余热锅炉性能的一系列措施;余热锅炉的性能优劣直接影响到燃气-蒸汽联合循环机组的整体运行,是燃气-蒸汽联合循环机组高参数、大型化发展的重要因素。     

9E燃气-蒸汽联合循环发电机组节能运行

目前,上海奉贤燃气轮机发电厂建有4套9E燃气-蒸汽联合循环发电机组,总装机容量为720 MW,是国内较为先进的燃气-蒸汽联合循环发电机机组.介绍了4套联合循环发电机组投产以来,结合机组和上海电网的运行特点,通过技术改进,采取有效措施在节能降耗、减本增效、优化运行方面做了积极探索,取得了明显的成效.     

燃气轮机联合循环机组一次调频能力分析与优化方法研究

为实现燃气-蒸汽联合循环机组一次调频能力的分析与优化,构建了能够考虑燃气轮机、余热锅炉、汽轮发电机组等主设备出力调节速率限制因素,并且可以兼顾机组运行状态分析的通用燃气-蒸汽联合循环机组一次调频能力分析模型。对不同发电负荷下联合循环机组一次调频能力及其影响因素进行了分析,并提出了通过机组一次调频响应滞后时间补偿、实际转速不等率补偿两种方法来实现机组一次调频能力的优化。     

生物质整体气化联合循环中燃烧室的(火用)分析

基于联合循环和能量梯级利用的概念，用[火用]分析和燃气变比热热力计算法研究生物质整体气化联合循环（BIGCC）中燃烧室的能量利用与损失情况。计算结果表明：燃用生物质燃料气，随燃气轮机初温提高，燃气轮机热效率提高，燃烧室的[火用]效率提高，但随燃烧室出口燃气温度的升高，燃烧室的[火用]效率提高幅度变缓；燃烧室的[火用]效率不仅与燃烧室燃气出口温度、空气入口温度和压力密切有关，还与燃料的组分的相对含量和发热量有关；对生物质燃料气、两种不同热值煤气在燃烧室出口燃气温度为1147℃时的燃烧室的[火用]效率进行了比较，两种不同热值煤气的[火用]效率较低，生物质燃料气[火用]效率最大。图2表2参1l     

蒸-燃联合循环与燃-燃联合循环的模拟和对比

蒸汽-燃气联合循环装置由于其较高的发电效率而被广泛应用于各大、中型电厂。然而,在微小型燃气-蒸汽发电装置中,蒸汽轮机的应用无疑使得装置体积和成本费用大增。因此,本文提出在小型分布式发电装置中,采用环境压力吸热燃气轮机循环（APGC）装置来替代蒸汽轮机装置吸收燃气轮机排出的废气能量,组成燃-燃联合循环,增加系统本身的做功能力和效率,达到节能、减少燃料消耗的目的。本文从热力学第一定律和第二定律出发,基于ASPENPLUS软件分别建立了燃-燃联合循环、蒸-燃联合循环模型,比较分析了两种循环装置在能量质量和数量上的利用程度。结果表明：燃-燃联合循环装置的效率较高,这在要求能源高效利用的今天具有一定的理论意义。     

燃气-蒸汽联合循环机组给水泵驱动改造及节能分析

本文提出了一种燃气-蒸汽联合循环机组给水泵改造方案,并建立了热效率计算模型。以某典型燃气-蒸汽联合循环机组在不同负荷下(60%～100%负荷)的运行参数为例,经计算分析得出:采用小汽轮机驱动给水泵的方式较电动机驱动每年可节约运行成本21. 4～36. 2万元,全厂热效率也有所提高,具有显著的经济效益。     

Parametric analysis and optimization for a combined power and refrigeration cycle

A combined power and refrigeration cycle is proposed, which combines the Rankine cycle and the absorption refrigeration cycle. This combined cycle uses a binary ammonia–water mixture as the working fluid and produces both power output and refrigeration output simultaneously with only one heat source. A parametric analysis is conducted to evaluate the effects of thermodynamic parameters on the performance of the combined cycle. It is shown that heat source temperature, environment temperature, refrigeration temperature, turbine inlet pressure, turbine inlet temperature, and basic solution ammonia concentration have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. A parameter optimization is achieved by means of genetic algorithm to reach the maximum exergy efficiency. The optimized exergy efficiency is 43.06% under the given condition.     

中冷技术对涡轮增压柴油机性能影响的研究

对废气涡轮增压中冷柴油机理论循环热效率进行了辨析.应用Matlab语言和Avl Boost软件,对EQ6102D柴油机工作循环进行了建模、编程和模拟计算,并对发动机进行了水冷和空冷2种模式的试验,计算与试验结果均表明中冷技术在提高发动机功率、降低排气温度和抑制NO_x生成方面效果显著,在提高热效率方面效果不明显,深度中冷加上适当增大空燃比,可提高热效率约5%.     

Parametric analysis for a new combined power and ejector–absorption refrigeration cycle

A new combined power and ejector–absorption refrigeration cycle is proposed, which combines the Rankine cycle and the ejector–absorption refrigeration cycle, and could produce both power output and refrigeration output simultaneously. This combined cycle, which originates from the cycle proposed by authors previously, introduces an ejector between the rectifier and the condenser, and provides a performance improvement without greatly increasing the complexity of the system. A parametric analysis is conducted to evaluate the effects of the key thermodynamic parameters on the cycle performance. It is shown that heat source temperature, condenser temperature, evaporator temperature, turbine inlet pressure, turbine inlet temperature, and basic solution ammonia concentration have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. It is evident that the ejector can improve the performance of the combined cycle proposed by authors previously.     

应用多工质朗肯循环提高火电厂效率

由于水蒸汽的热力性质所限制,常规火力发电厂应用的水蒸汽朗肯循环效率大大地低于同温差下的卡诺循环效率.在现代技术条件下;其效率一般在42%以下,而采用钾-联苯-水蒸汽三工质朗肯循环,或采用钾-水蒸汽二工质朗肯循环可使火电厂热效率提高到50%以上,能节约燃料35%左右,同时也大大地减轻了火力发电厂对环境的各种污染.在多工质朗肯循环中,必须根据各工质的热力学性质优化选择各工质的参数,充分发挥循环特性接近卡诺循环的作用,同时应解决好泄漏问题和选用合适的耐高温材料.在燃料价格及年运行小时较高时,多工质朗肯循环还是有较好的经济性.图3表1参9     

600MW机组加热器增加疏水冷却段热经济分析

热力发电厂回热加热器增加疏水冷却段时可以降低该加热器放流到下一级加热器的疏水温度,从而减小了该疏水在下一级加热器的热交换温差,减小了不可逆性,达到了降低全厂热耗和节能的目的.文中采用循环函数法,通过对不同形式的加热器进行计算和比较,表明600MW机组回热系统在采用加热器增加疏水冷却段时会提高全厂的循环效率.     

Energy and exergy analyses of a CFB‐based indirectly fired combined cycle power generation system

Combined cycle configuration has the ability to use the waste heat from the gas turbine exhaust gas using the heat recovery steam generator for the bottoming steam cycle. In the current study, a natural gas‐fired combined cycle with indirectly fired heating for additional work output is investigated for configurations with and without reheat combustor (RHC) in the gas turbine. The mass flow rate of coal for the indirect‐firing mode in circulating fluidized bed (CFB) combustor is estimated based on fixed natural gas input for the gas turbine combustion chamber (GTCC). The effects of pressure ratio, gas turbine inlet temperature, inlet temperatures to the air compressor and to the GTCC on the overall cycle performance of the combined cycle configuration are analysed. The combined cycle efficiency increases with pressure ratio up to the optimum value. Both efficiency and net work output for the combined cycle increase with gas turbine inlet temperature. The efficiency decreases with increase in the air compressor inlet temperature. The indirect firing of coal shows reduced use with increase in the turbine inlet temperature due to increase in the use of natural gas. There is little variation in the efficiency with increase in GTCC inlet temperature resulting in increased use of coal. The combined cycle having the two‐stage gas turbine with RHC has significantly higher efficiency and net work output compared with the cycle without RHC. The exergetic efficiency also increases with increase in the gas turbine inlet temperature. The exergy destruction is highest for the CFB combustor followed by the GTCC. The analyses show that the indirectly fired mode of the combined cycle offers better performance and opportunities for additional net work output by using solid fuels (coal in this case). Copyright © 2009 John Wiley & Sons, Ltd.     

Performance improvement of combined cycle power plant based on the optimization of the bottom cycle and heat recuperation

Many F class gas turbine combined cycle(GTCC)power plants are built in China at present because of less emis-sion and high efficiency.It is of great interest to investigate the efficiency improvement of GTCC plant.A com-bined cycle with three-pressure reheat heat recovery steam generator(HRSG)is selected for study in this paper.In order to maximize the GTCC efficiency,the optimization of the HRSG operating parameters is performed.Theoperating parameters are determined by means of a thermodynamic analysis,i.e.the minimization of exergylosses.The influence of HRSG inlet gas temperature on the steam bottoming cycle efficiency is discussed.Theresult shows that increasing the HRSG inlet temperature has less improvement to steam cycle efficiency when itis over 590℃.Partial gas to gas recuperation in the topping cycle is studied.Joining HRSG optimization with theuse of gas to gas heat recuperation,the combined plant efficiency can rise up to 59.05% at base load.In addition,the part load performance of the GTCC power plant gets much better.The efficiency is increased by 2.11% at75% load and by 4.17% at 50% load.     

具有空气冷却的简单循环燃气轮机热力学建模和性能优化:(I)建模

研究了考虑空气冷却和实际气体性质的简单循环三轴燃气轮机热力学性能,给出了循环功率和效率的计算流程,并利用UGT25000型工业燃气轮机的设计性能数据对模型进行了验证计算。结果表明,所建模型是准确的,能有效地反映燃气轮机循环的设计性能。     

基于超临界CO2循环的地热与太阳能混合系统研究

超临界CO₂循环可以耦合较低温度的地热和较高温度的太阳能热组成混合热源发电系统。相比能量分析方法,火用分析方法更便于分析混合系统对提高能量利用率的作用,以及识别造成可用能损失的设备和过程。115℃地热和200℃地热分别与采用槽式聚光集热技术的太阳能热组成混合热源,构成简单回热超临界CO₂循环。分析结果表明：混合系统的火用效率比单纯太阳能热的循环系统提高了5% ~ 10%;太阳能聚光集热器的?损失最大,占80%以上,其次是除预冷器以外的各类换热器以及透平;相比之下,压缩机和预冷器的火用损失较小。减少?损失的关键是提高太阳能聚光集热器和换热器的性能,包括提高集热管运行温度,以及提高换热器效能。     

Exergy and Energy Analysis of Combined Cycle systems with Different Bottoming Cycle Configurations

The paper deals with thermodynamic analysis of cooled gas turbine‐based gas‐steam combined cycle with single, dual, or triple pressure bottoming cycle configuration. The cooled gas turbine analyzed here uses air as blade coolant. Component‐wise non‐dimensionalized exergy destruction of the bottoming cycle has been quantified with the objective to identify the major sources of exergy destruction. The mass of steam generated in different configurations of heat recovery steam generator (HRSG) depends upon the number of steam pressure drums, desired pressure level, and steam temperature. For the selected set of operating parameters, maximum steam has been observed to be generated in the case of triple pressure HRSG = 19 kg/kg and minimum in single pressure HRSG = 17.25 kg/kg. Plant‐efficiency and plant‐specific works are both highest for triple‐pressure bottoming cycle combined cycle. Non‐dimensionalized exergy destruction in HRSG is least at 0.9% for B3P, whereas 1.23% for B2P, and highest at 3.2% for B1P illustrating that process irreversibility is least in the case of B3P and highest in B1P. Copyright © 2012 John Wiley & Sons, Ltd.