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1、毕业设计(论文)摘要除氧器的水箱是为保证锅炉有一定的给水储备而设置的,其容量一般不应小于锅炉额定负荷下连续运行15~20min所需的给水量。除氧器水位过低,储水量不足有可能危及锅炉的安全运行,此外还有可能造成给水泵入口汽化。除氧器水位过高,则妨碍除氧器除氧。因此,除氧器水位应维持在容许范围内。由于热力循环中不断有工质损失,因此要向热力系统不断补充水。补充水来自化学水处理装置。补充水可直接进入除氧器,也可以送凝汽器进行真空除氧后在送至除氧器。火力发电厂的热力除氧器利用汽轮机的抽气加热锅炉给水,使得锅炉的给水达到该压力下相应的饱和温度,以除去溶于水中的氧气等气体,防止锅炉、汽轮机和管道等热
2、力设备遭到腐蚀,另一方面除氧器是汽水直接接触式的加热器,它是给水加热系统中的一环,利用汽轮机的抽气加热锅炉给水,可以提高电厂效率,节省燃料。除氧器是电厂重要的辅助设备之一,是电厂热力系统中不可缺少的环节。所以说除氧器的水位控制对锅炉的安全稳定运行至关重要。关键字除氧器,水位调节,单冲量,串级三冲量III毕业设计(论文)AbstractDeaeratorwatertankistoensurethattheboilerhasawaterreserveandsettings,itscapacityshouldgenerallynotbelessthanratedboilerloadconti
3、nuousoperationfor15~20mintowater. Deaeratorwaterleveltoolow,insufficientstoragecapacitymayendangerthesafeoperationoftheboiler,inadditiontomayresultinginwaterpumpinletvaporization.Deaeratorwaterlevelistoohigh,obstructsthedeaerating.Therefore,thedeaeratorwaterlevelshouldbemaintainedwithin the allo
4、wablerange.The thermodynamiccycleof constantly refrigerantloss, thereforetothermalsystemcontinuouslyadd water.Thechemicalwatertreatmentfromwatersupplementdevice.Watercanbedirectlyadded tothedeaerator,alsocansendcondenservacuumdeaerator aftersenttothedeaerator.Thermalpowerplantdeaeratorusesteamt
5、urbinepumpinggasheatingboiler,theboilerfeedwaterthepressurecorrespondingsaturationtemperatureisreached,toremovedissolvedinthewaterofoxygenandothergases,topreventtheboiler,turbineandpipelinebythermalequipmentcorrosionandtheothersidesurfaceofthedeaeratorissteamwaterdirectcontactoftheheater,itiswat
6、erheatingsysteminaring,theuseofsteamturbinepumpinggasheatingboilerfeedwater,canimprovetheefficiencyofpowerplantsandfuelsaving. Thedeaerator isoneoftheimportantauxiliary equipmentofpowerplant, isanindispensable linkinthe powerplantthermalsystem. Sothedeaeratorwaterlevelcontrol iscrucialto thesafe
7、andstableoperationof theboiler.KeywordsDeaerator,Waterleveladjustment,Singleimpulse,CascadethreeimpulseIII毕业设计(论文)目录摘要IAbstractII1引言12除氧器的概况22.1除氧器介绍22.1.1概述22.1.2除氧器的除氧原理22.1.3除氧器的工作原理32.1.4除氧器控制任务32.2控制仪表知识简介42.2.1变送器42.2.