【甲醇生產(chǎn)設計中的熱量衡算案例綜述2000字】

甲醇生產(chǎn)設計中的熱量衡算案例綜述1.1甲醇合成塔圖3甲醇合成塔熱量圖工藝條件：進塔的溫度：T1=95℃；出塔的溫度T2=190℃；塔壓力P1=9.4MPa；出塔壓力P2=9.0MPa。計算公式：ΣQ入塔氣+ΣQr=ΣQ出塔氣+ΣQ熱損失Q入塔氣—入塔各氣體組分熱量；KJ/hQr—合成反應和副反應的反應熱；KJ/hQ出塔氣—出塔各氣體組分分熱量；KJ/hQ熱損失—合成塔熱損失；KJ/h1.全塔入塔氣的計算：計算常壓下,368.2K理想氣體多項方程式:Ceq\o(\s\up12(id),\s\do4(pm))=a+bT+cT2+dT3查<<華工工藝過程計算>>及<<物理化學>>物性數(shù)據(jù)表,各組分的比熱容如下表所示表15入塔各組分比熱容組分項目CH3OHH2N2COCO2CH4合計比熱容KJ/kmol﹒kkJ/(kmol·K)52.176.9429.4529.2140.3839.45218.426入塔氣量409.0688403.88278255470.041856.501199.72124597.02kmol/hh18.263946.401242.19244.2082.88586.745526.16摩爾比率%（％）0.0470.9522.334.391.490.47100PC(MPa)7.951.33.43.57.384.64\TC(K)513.233.3126132.9304.2190.7\Ceq\o(\s\up6(o),\s\do2(pm))=52.17×0.0004+6.94×0.7095+29.45×0.2233+29.21×0.0439+40.38×0.0149+39.45×0.0047=13.59KJ/Kmol·KPcm=7.95×0.0004+1.3×0.7095+3.4×0.2233+3.5×0.0439+7.38×0.0149+4.64×0.0047=1.97MPaTcm=513.2×0.0004+33.3×0.7095+126×0.2233+132.9×0.0439+304.2×0.0149+190.7×0.0047=63.23K當P=9.4mPa,T=368.2K時Pr=P/Pcm=9.4/1.97=4.7Tr=T/Tcm=368.2/63.23=5.8查<<化工工藝過程計算>>圖4-2得ΔCpm=0.07J/Kmol·K混合氣體Cpm=Ceq\o(\s\up12(o),\s\do4(pm))+ΔCpm=13.59+0.07=13.66J/Kmol·KΣQ入塔氣=nCpmT入=5562.16×13.66×368.2=27975506.68KJ/h2.塔內反應熱表16甲醇合成塔內反應熱項目╲組分CH3OHCH4CO合計生成熱KJ/mol﹒k102.3749.62-42.92/反應熱KJ/h150893388931.6-509460.414588809.2生成熱量Nm3/h3301.74.0265.83571.5Kmol/h147.40.1811.87159.453.塔出口溫度的計算合成塔出塔各組分的比熱容(常壓下,463.2K)甲醇:Ceq\o(\s\up6(id),\s\do2(pm))=18.40+101.56×10-3×463.2-26.68×10-6×(463.2)2=59.72KJ/Kmol·K水:Ceq\o(\s\up6(id),\s\do2(pm))=29.16+14.49×10-3×463.2-2.022×10-6463.22=35.44KJ/Kmol·K甲烷:Ceq\o(\s\up6(id),\s\do2(pm))=14.32+74.66×10-3×463.2-17.43×10-6×463.22=41.16KJ/Kmol·K氮氣:Ceq\o(\s\up6(id),\s\do2(pm))=27.32+6.226×10-3×463.2-0.9502×10-6×463.22=30.0KJ/Kmol·K一氧化碳:Ceq\o(\s\up6(id),\s\do2(pm))=26.537+7.6831×10-3×463.2-1.172×10-6×463.22=29.85KJ/Kmol·K二氧化碳:Ceq\o(\s\up6(id),\s\do2(pm))=26.75+42.258×10-3×463.2-14.25×10-6×463.22=43.26KJ/Kmol·K氫氣:Ceq\o(\s\up6(id),\s\do2(pm))=6.953-0.046×10-3×463.2+0.096×10-6×463.22-0.21×10-9×463.23=6.93KJ/Kmol·K表17出塔氣比熱容表組分項目CH3OHH2N2COCO2CH4H2O合計比熱容kJ/(kmol·K)59.726.9330.029.8543.2641.1635.44\出塔氣量Nm3/h35522.5480952.7278252158.71590.7624.94351.9149026.48kmol/h332.493613.961242.296.471.027.915.715399.66摩爾比率（％）3.168.923.81.971.420.510.3100PC(MPa)5.271.33.43.57.384.6422.12\Tc(K)55033.3126132.9304.2190.7647.4\Pcm=0.031×5.27+0.689×1.3+0.238×3.4+0.0197×3.5+0.0142×7.38+0.0051×4.64+0.003×22.12=2.13MPaTcm=0.031×550+0.689×33.3+0.238×126+0.0197×132.9+0.0142×304.2+0.0051×190.7+0.003×647.4=79.83KCeq\o(\s\up6(o),\s\do2(pm))=0.031×59.72+0.689×6.93+0.238×30+0.0197×29.85+0.0142×43.26+0.0051×41.16+0.003×35.44=15.28KJ/Kmol·K當P=9.4mPa,T=463.2K時;Pr=P/Pcm=9.4/2.13=4.41;Tr=T/Tcm=463.2/79.83=5.80查<<化工工藝過程計算>>得:ΔCpm=0.062J/mol·K混合氣體Cpm=Ceq\o(\s\up6(o),\s\do2(pm))+ΔCpm=15.28+0.062=15.34KJ/Kmol·KΣQ出塔氣=nCpmT出=5399.66×15.34×463.2=38367219.33KJ/h44.合成塔熱損失計算按全塔熱平衡方程式:ΣQ入塔氣+ΣQr=ΣQ出塔氣+ΣQ熱損失27975506.68+14588809.2=38367219.33+ΣQ熱損失ΣQ熱損失=X%(ΣQ入塔氣+ΣQr)=X%(27975506.68+14588809.2)=4197096.55KJ/h∴X=9.8表18甲醇合成塔全塔熱平衡表熱量氣體熱反應熱熱損失合計入熱KJ/h27975506.6814588809.2\42564315.88出熱KJ/h38367219.33\4197096.5542564315.881.2廢熱鍋爐的熱量衡算Kg/h圖4廢熱鍋爐熱量圖工藝條件：1.入廢熱鍋爐的氣體溫度T1=190℃；出口溫度T2=163℃2.壓力P1=9.0MPa；P2=9.0MPa；氣流量3770.1Kmol/h3.廢熱鍋爐水的溫度t1=100℃；出口飽和水蒸汽的溫度t2=151.7℃1.計算公式∑Q放=∑Q吸熱損失忽略不計式中:Q吸——物質在廢熱鍋爐中所吸收的熱量，kJ/h；Q放——物質在廢熱鍋爐中所釋放的熱量，kJ/h;進廢熱鍋爐氣體熱量計算Q進廢熱鍋爐=Q出塔氣=38367219.33kJh3.出廢熱鍋爐氣體的熱量衡算經(jīng)氣體摩爾定壓熱容與溫度的關系式計算得P=0.1MPa，T1=110+273.15=383.15K時各組分的比熱容如下表所示表19常壓下出廢熱鍋爐氣體各組分比熱容表組分項目CH3OHH2N2COCO2CH4H2O合計比 熱 容kJ/(kmol·K)58.2728.7529.929.7242.7244.0734.42\出氣量Nm3/h3723.757262.919115.73066.6269.6623.4389.6784451.57kmol/h166.22556.4853.4136.912.027.817.403770.1摩爾比率（％）4.4269.3622.293.240.220.340.13100PC(MPa)7.951.33.43.57.384.6422.12\TC(K)513.233.3126133304.2190.7647.4\Pcm=0.0442×7.95+0.6936×1.3+0.2229×3.4+0.0324×3.5+0.0022×7.38+0.0034×4.64+0.0013×22.12=2.19MPaTcm=0.0442×513.2+0.6936×33.3+0.2229×126+0.0324×133+0.0022×304.2+0.0034×190.7+0.0013×647.4=80.33KCeq\o(\s\up6(o),\s\do2(pm))=58.27×0.0442+28.75×0.6936+29.9×0.2229+29.72×0.0324+42.72×0.0022+44.07×0.0034+34.42×0.0013=30.43kJ/Kmol·K當P=9.0+8.9/2＝8.9MPa，T=444.65K時Pr=P/PCM=9.0/2.19=4.11Tr=T/TCM=444.65/80.33＝5.54查《化工工藝過程計算》得△CPM=0.14KJ/Kmol·K混合氣體CPM＝CP0M+△CPM＝30.43+0.14＝30.57kJ/Kmol·KQ放＝∑n入CPM（t進-t出）=3770.1×30.57×（190-163）＝4264322.41KJ/h廢熱鍋爐的蒸汽量查水和水蒸氣表，在P＝0.5MPa下，100℃時的焓h1＝418.68KJ/Kg，在P＝0.5MPa下，151.7℃時飽和水蒸氣的焓h2＝2752.8KJ/Kg根據(jù)Q吸＝Q放G蒸汽（h2-h1）＝4264322.41KJ/hG蒸汽＝4264322.41/（2752.8-418.68）=1826.95Kg/h1.3預熱器的熱量衡算圖5預熱器熱量圖工藝條件：進預熱器氣體溫度T1=153℃；出預熱器的氣體溫度T2=79℃；壓力P1=8.9MPa；P2=8.8MPa；主線進預熱器溫度t1=30℃出預熱器溫度t2=140℃忽略熱損失。1.計算公式Q放=Q放式中：Q吸——物質在預熱器中所吸收的熱量，kJ/h；Q放——物質在預熱器中所釋放的熱量，kJ/h;1、常壓下389.15K時，出廢熱鍋爐的各組分的比熱容甲醇：CEQ\o(\s\up5(id),\s\do2(pm))=18.40+101.56×10-3×389.15-26.68×10-6×389.152=53.88kJ/Kmol·K水：CEQ\o(\s\up5(id),\s\do2(pm))=29.16+14.49×10-3×389.15-2.022×10-6×389.152=34.22kJ/Kmol·K甲烷：CEQ\o(\s\up5(id),\s\do2(pm))=14.15+75.496×10-3×389.15-17.99×10-6×389.152=40.74kJ/Kmol·K氮氣：CEQ\o(\s\up5(id),\s\do2(pm))=27.32+6.226×10-3×389.15-0.9502×10-6×389.152=29.60J/Kmol·K一氧化碳：CEQ\o(\s\up5(id),\s\do2(pm))=26.537+7.683×10-3×389.15-1.172×106×389.152=29.27kJ/Kmol·K二氧化碳：CEQ\o(\s\up5(id),\s\do2(pm))=26.75+42.258×10-3×389.15-14.25×10-6×389.152=41.04kJ/Kmol·K氫氣：CEQ\o(\s\up5(id),\s\do2(pm))=26.88+4.347×10-3×389.15-0.3265×10-6×389.152=28.52kJ/Kmol·K表20常壓下預熱器氣體各組分比熱容表組分項目CH3OHH2N2COCO2CH4合計比 熱 容kJ/(kmol·K)53.8828.5229.6029.2741.0440.74\氣體流量Nm3/h3723.757262.919115.73066.6269.6623.484061.9kmol/h166.22556.4853.4136.912.027.83752.7摩爾比率（％）4.4268.1322.753.650.330.72100PC(MPa)7.951.33.43.57.384.59\TC(K)513.233.2126133304.4190.6\Pcm=7.95×0.0442+1.3×0.6813+3.4×0.2275+3.5×0.0365+7.38×0.0033+4.59×0.0072=2.19MPaTcm=513.2×0.0442+33.2×0.6813+126×0.2275+133×0.0365+304.4×0.0033+190.6×0.0072=81.19kCeq\o(\s\up6(o),\s\do2(pm))=53.88×0.0442+28.52×0.6813+29.6×0.2275+29.27×0.0365+41.04×0.0033+40.74×0.0072=30.04kJ/Kmol·K當P=9.0+8.9/2＝8.85MPa，T=389.15K時Pr=P/PCM=8.85/2.19=4.04Tr=T/TCM=389.15/81.19＝4.79查《化工工藝過程計算》得△CPM=0.3KJ/Kmol·K混合氣體CPM＝CP0M+△CPM＝30.04+0.3＝30.34kJ/Kmol·KQ吸＝∑n入CPM（T進-T出）=3752.7×30.34×（153-79）＝8425411.93KJ/h預熱器主線的氣體流量經(jīng)氣體摩爾定壓熱容與溫度的關系式計算得P=0.1MPa，T1=（30+75）/2+273.15=325.65K時各組分的比熱容如下表所示表21常壓下預熱器主線氣體各組分比熱容表組分項目CH3OHH2N2COCO2CH4合計比 熱 容kJ/(kmol·K)51.3528.4429.4329.1440.0638.82\氣體流量Nm3/h72.739520.311639.04018.6284.5369.655904.7kmol/h3.21764.3519.6179.412.716.52495.7摩爾比率（％）4.4268.1322.753.650.330.72100PC(MPa)7.951.33.43.57.384.59\TC(K)513.233.2126133304.4190.6\Pcm=7.95×0.0442+1.3×0.6813+3.4×0.2275+3.5×0.0365+7.38×0.0033+4.59×0.0072=2.19MPaTcm=513.2×0.0442+33.2×0.6813+126×0.2275+133×0.0365+304.4×0.0033+190.6×0.0072=81.19kCeq\o(\s\up6(o),\s\do2(pm))=51.35×0.0442+28.44×0.6813+29.43×0.2275+29.14×0.0365+40.06×0.0033+38.82×0.0072=29.82kJ/Kmol·K當P=9.0+8.9/2＝8.85MPa，T=358.15K時Pr=P/PCM=8.85/2.19=4.04Tr=T/TCM=358.15/82.19＝4.79查《化工工藝過程計算》得△CPM=0.38KJ/Kmol·K混合氣體CPM＝CP0M+△CPM＝29.82+0.38＝30.2kJ/Kmol·KQ放＝∑n主CPM（t出-t進）=∑n主×3020×（140-30）又因為Q放＝Q吸,所以∑n主＝8425411.93/30.2×110＝2536.25Kmol/h主線氣量摩爾分率＝主線氣量/總進氣量＝2536.25/3752.7＝67.58％表22預熱器平衡表帶入熱量KJ/h帶出熱量KJ/h8425411.938425411.931.4水冷汽的熱量衡算Kg/h圖6水冷器熱量圖工藝條件：1進水冷器氣體溫度T1=79℃；出水冷器的氣體溫度T2=38℃；2進出口壓力P1=8.8MpaP2=8.7Mpa3冷卻水進口溫度t1=30℃出口溫度t2=45℃4水冷器氣量168891.71Nm3/h計算公式∑Q入口量+∑Q冷凝器=∑Q出口氣+∑Q液體+∑Q冷卻水式中∑Q入口量—入口熱入熱量；KJ/h∑Q冷凝器—在出口溫度下氣體冷凝放熱；KJ/h∑Q出口氣—出