本科毕业设计火电机组加热器端差对经济性影响的分析.docx

火电机组加热器端差对经济性影响的分析摘要：讨论汽轮机组的经济性问题，人们往往把目光放在汽轮机的初终参数上，认为它们的变化对机组的经济性影响较大，这无疑是正确的。但分析整台机组的经济性仅限于此也是不全面的。还应关注汽轮机的回热系统，因为汽轮机的回热系统也有相当的节能潜力，认真分析其中存在的问题，也能找到节能的途径和办法，其中汽轮机热力系统中的加热器的运行情况,对机组经济性有较大的影响，主要表现在加热器的端差（包括运行中的加热不足）、抽汽管道压损、散热损失、切除加热器和给水部分旁路等因素对热经济性的影响。定量分析这些因素对热经济性的影响，对于机组节能和提高机组热经济性具有十分现实的意义。在这些因素中，传热端差的影响尤其大，本文运用等效热降理论，以600MW和350MW机组为例定量分析了加热器端差变化对机组热经济性的影响，结果表明加热器端差越小,机组的热经济性越高,加热器端差越大,机组的热经济性越低，这为电厂给水回热系统节能改造提供了依据，本文还总结了加热器端差增大的原因，并提出了相应的改进措施。关键词：加热器，端差，等效热降法，经济性TheAnalysisofThermalEconomiconTerminalTemperatureDifferenceofHeaterinPowerUnitAbstract：Disscussingtheeconomicissusesofturbine,peopletendtopayaattentiontotheinitialandfinalparametersoftheturbine,andthinktheirchangeswilleffectgreatlyonunit’seconomy,whichisundoubtedlycorrect.However,itiscomprehensivetosimplyanalyze.theeconomyoftheentireunit.Becausetheheatrecoverysystemofsteamturbinehasconsiderablepotentialforenergysaving,weshouldalsoconcernheatrecoverysystemofsteamturbine,andanalyzetheexistingproblemscarefullytofindthewaystoenergysaving.Heaterterminaltemperaturedifferenceofsteamturbinethermalsystemcancausegreatinfectionsonunit’seconomy,anditmainlyexpressestheimpactsaboutheaterterminaltemperaturedifference,thelossofpressurealongpipe,thelossofheat,theresectionofhighpressurefeedwaterheater,andthebypassofsupplyingwater,andsoon.Analyzingtheimpactonunit’shoteconomybythesefactorshasrealisticsignificancefortheunit’senergysavingandimprovingtheunit’shoteconomy.Theterminaltemperaturedifferenceinfluencegreatlyamongthesefactors.Thispapertookthe600MWand350MWunitsasanexample,equivalentheatdropmethodwasadoptedforanalyzingheaterterminaltemperaturedifferenceeffectonunit’seconomic.Theresultsindicated:thesmallerheaterterminaltemperaturedifference,thehigherunit’seconomic;thebiggerheaterterminaltemperaturedifference,thelowerunit’seconomic,anditprovidedtheevidenceforenergysaving.Thispapersummarisedthereasonsforincreasingdifference,andputforwardmeasuresforimprovement.Keywords:heater，terminaltemperaturedifference，equivalentheatdro