一、设计任务书:(一)、课程设计的任务热力发电厂课程设计的主要任务是按照给定的设计条件,完成300MW凝汽式汽轮发电机组原则性热力系统计算;完成300MW机组全面性热力系统图、300MW机组原则性热力系统图的绘制。通过以上设计计算工作,要求掌握300MW汽轮发电机组全厂热力系统计算方法,确定全厂的热经济性。掌握300MW机组全面性热力系统图的绘制方法。(二)、课程设计的内容及主要要求热力发电厂课程设计包括发电厂原则性热力系统计算。热力系统设计的主要内容和设计过程包括(详细计算方法参考文献1):1.整理原始资料根据给定的已知条件(全厂电功率、全厂原则性热力系统图、计算用汽水参数等),求得计算点各处的汽水焓值(查h-s图),并确定某些辅助设备的汽水流量和效率。2.进行全厂物质平衡。3.进行回热系统计算。4.汽轮机组及全厂热经济指标计算。5.计算结果汇总表。6.完成300MW机组原则性热力系统图(3号图纸)、全面性热力系统图绘制(1号图纸),将计算出的数据标在原则性热力系统图上。7.最终提交课程设计纸质文本的纸型:A4纸质文本组成:封面、任务书、目录、正文。(三)、原始资料1.热力系统结构及参数见附图。机组型号N300-16.17/535/535额定工况Nd=300MW2.锅炉参数Pb=16.66MPa;tb=540℃汽包压力Pbq=19.67MPa3.其他参数主汽门压损2%再热器系统压损12%中低压联通管压损2%小汽机抽汽管道及阀门压损8%各加热器抽汽管道及阀门压损6%锅炉排污量:Dbl=0.01Db全厂汽水损失Dl=0.01Db锅炉效率ηb=0.92机械、电机效率ηmηg=0.98加热器及除氧器效率ηh=0.99排污扩容器效率ηf=0.98补充水温度tma=20℃排污扩容蒸汽压损△Pbl=0.06MPa4.各加热器上、下端差如下:项目JG1JG2JG3CYJD1JD2JD3JD4上端差-10-100233下端差5.65.65.6-----(四)、参考文献1.严俊杰等,发电厂热力系统及设备,西安交通大学出版社,20032.冯慧雯,汽轮机课程设计参考资料,水利电力出版社,19913.沈士一等,汽轮机原理,水利电力出版社,19924.叶涛,热力发电厂,中国电力出版社,2009二、原始资料整理1、已知全部参数(1)汽轮机机组形式N300-16.17/535/535新蒸汽参数P0=16.17Mpa,t0=535℃,h0=3394.601318kJ/kg再热蒸汽参数高压缸排汽t2=324.66℃,Prh=3.59Mpa,h2=3041.232178kJ/kg中压缸进汽trh=535℃,p'rh=3.1592Mpa,hrh=3532.881592kJ/kg排气压力Pc=0.0051Mpa,hc=136.110840kJ/kg(2)锅炉型式和参数主蒸汽参数Pb=16.66MPa;tb=540℃,hb=3402.948486kJ/kg汽包压力Pbq=19.67MPa再热蒸汽出口温度trh=535℃锅炉效率ηb=0.92(3)回热抽气八级回热抽气给水温度给水泵焓升=30.584kj/kg计算中的选用数据锅炉排污量Dbl=0.01Db全厂汽水损失Dl=0.01Db加热器及除氧器效率ηh=0.99排污扩容器效率ηf=0.98补充水温度tma=20℃,hm=84.141739kJ/kg连续排污扩容压力0.75Mpa(扩容蒸汽进入除氧器),见表1计算工况下机械电机效率ηmηg=0.98小汽机抽汽管道及阀门压损8%各加热器抽汽管道及阀门压损6%表1排污扩容器计算点汽水参数汽水参数单位锅炉汽包排污水连续排污扩容器压力Mpa19.670.75温度℃364167.757629汽焓kJ/kg2764.834229水焓kJ/kg1804.061890709.3009642、全部计算结果(1)整理原始资料,按照简捷计算焓值如下再热焓升qrh=491.649414kJ/kg各加热器出口焓值见表2表2各加热器进出口焓值加热器序号抽汽焓进口疏水焓出口疏水焓进口水焓出口水焓iiqi12482.763671221.488403139.24736208.94358869.6962282261.27526822688.982666531.954285208.943588363.459869154.5162812480.039078323.01069732901.481934618.108643531.954285363.459869523.444824159.9849552369.52764986.15435843017.977783618.108643523.444824618.10864394.6638192399.8691453122.179932750.717041618.108643694.28448576.1758422504.071289132.60839863300.3396855.891357750.717041724.284485832.050476107.7659912549.622559105.17431673047.0266111066.688599855.891357832.0504761039.765015207.7145392191.135254210.79724283128.090821066.6885991039.7650151153.940474114.1754592061.402221.(2)全厂物质平衡计算全厂汽水损失Dl=0.01Db=0.01*1.0101D0=0.010101D0锅炉蒸发量Db=D0+D1=D0+0.010101D0=1.010101D0锅炉连续排污量Dbl=0.01Db=0.010101D0给水量Dfw=Db+Dbl=1.010101D0+0.010101D0=1.020202D0轴封漏气量1Dsg1=0.00608D0轴封漏气量2Dsg2=0.000263D0轴封漏气量3Dsg3=0.00233D0轴封漏气量4Dsg4=0.0012D0轴封漏气参数见表3表3轴封漏气参数序号sgi1/kgkJqsgi1/kgkJhsgi流向10.006082276.4114013343.11号高加20.0002632721.9029593472.623号高加30.002332423.0513573041.16除氧器40.00122467.51159726894号低加由排污扩容器热平衡计算Df,D'bl0blffffblfD0101.0300964.709834229.2764300964.70998.0233032.1806Dt-ht-tD0.00521234805D0未回收的排污水量000fblbl1946D0.00488765805D0.00521234-0.0101DD-DD'补充水量000bllmD0.014988651946D0.004887650.010101DD'DD(3)回热加热器抽汽系数计算①高压加热器GJ1计算0h8sg1sg18fw8D050295004.0qqD-DD②高压加热器GJ2计算0h77sg187fw7D0922.0q)D(D-DD③高压加热器GJ3计算No7的疏水量0sg1877D148586367.0DDD再热蒸汽量0sg4sg3sg1780rhD847883633.0D-D-D-D-D-DD高压加热器GJ3抽汽量0h6sg2sg2676fw6D037082038.0qqD--DD高压加热器No6的疏水量0sg2676D185931405.0DD④除氧器CY计算进入除氧器的抽汽量0h533565fw5D014611956.0qDD'ffsgsgqDqD小汽轮机的抽汽量0stst5bfwD067413925.0)h-(hDDst除氧器的抽汽量0st55D082.0DD'DDJ1级回热加热器的出口水量06sg3f5fwfw4D812184583.0-D--DD'-DD⑤低压加热器DJ1计算0h44c44D032357837.0qDD⑥低压加热器DJ2计算低压加热器DJ2抽汽量0h3343fw43D054202315.0qDDD低压加热器N03的疏水量04332D0.08656015DD⑦低压加热器DJ3计算低压加热器DJ3抽汽量02222fw42D0397.0-DDhqDJ4级回热加热器的出口水量032fw4fw1D685898808.0-D-DD⑧低压加热器DJ4计算0h1sg4sg41fw11D020031401.0qqD-DD⑨凝气流量计算正平衡计算:0000000000000041sgi81ii0cD58226.0D0012.0D00233.0D000263.0D00608.0D020031401.0D0397.0D054202315.0D032357837.0D082.0D037082038.0D0922.0D050295004.0DDD-DDi反平衡计算:000000st4sgm1fw1cD58226.0D067413925.0D0012.0D01498865.0D020031401.0D685898808.0D-D-D-D-DD(四)计算D0由汽轮机功率方程:可得:各加热器抽汽及轴封漏气份额和焓值如表4表4D和h数据-1hD/t1kgh/kJD013394.601318Dzr0.8478836333532.881592D10.0200314012482.763671D20.03972688.982666D30.0542023152901.481934D40.0323578373017.977783D50.0823122.179932D60.0370820383300.3396D70.09223047.026611D80.0502950043128.09082Dsg10.006083343.1Dsg20.0002633472.62Dsg30.002333041.16Dsg40.00122689Dc0.582262380.51将上表数据代入公式得:D0=945.3397632t/h回热系统的各项汽水流量见表5表5各项汽水流量项目比例数值/(t/h)汽轮机汽秏D01945.29282543锅炉蒸发量Db1.010101954.84122826给水量Dfw1.020202964.38963109锅炉排污量Db10.0101019.5484028297扩容蒸汽量Df0.005212348054.9271952153未扩容蒸汽量D'bl0.0048876519464.6202623177全厂汽水损失D10.0101019.5484028297化学补水量Dm0.0149886514.168663308再热蒸汽量Drh0.847883633801.56677034第一级抽汽D10.02003140118.935472533第二级抽汽D20.039737.552020282第三级抽汽D30.05420231551.236964962第四级抽汽D40.03235783730.590203304第五级抽汽D50.08277.54237047第六级抽汽D60.03708203835.053634031第七级抽汽D70.092287.174108424第八级抽汽D80.05029500447.467682608汽轮机排气量Dc0.58226550.40620053小汽轮机耗汽量Dst0.06741392563.725899636①正平衡计算单位新蒸汽的循环内功为代入数据解得:0iDN1166kJ/h单位新蒸汽的循环吸热量为代入数据解得:0DQ2695.2kJ/h则循环内效率为QN