09 07 13 sol

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Esercizio 1: xO2= 3.5 % Combustione stechiometrica: CH4+2(O2+3.76N2) -> CO2+2H2O+7.52N2 Combustione con eccesso d'aria 'e': CH4+2*(1+e)*(O2+3.76N2) -> CO2+2H2O+2*eO2+7.52*(1+e)N2 xO2 =2*e/(10.52+2*e+7.52*e) = 0.035 e = 22.09 % fumi: zCO2 = 1 kmole/kmoleCH4 zH2O = 2 kmole/kmoleCH4 zO2 = 0.44 kmoli/kmoleCH4 zN2 = 9.18 kmoli/kmoleCH4 ztot = 12.62 kmoli_fumi/kmoleCH4 xCO2 = 0.0792 kmoli/kmole_fumi xH2O = 0.1584 kmoli/kmole_fumi xO2 = 0.0350 kmoli/kmole_fumi xN2 = 0.7273 kmoli/kmole_fumi cpCO2 = 39.2 kJ/kmole-K cpH2O = 34.3 kJ/kmole-K cpO2 = 30.0 kJ/kmole-K cpN2 = 29.5 kJ/kmole-K cp_fumi = 31.034 kJ/kmole-K Tcamino = 120 °C Tamb = 25 °C PCI_CH4 = 50 MJ/kg PCI_CH4 = 800 MJ/kmole Qcamino = 37215.9 kJ/kmoleCH4 Qcamino = 0.0465 kJ/kJPCI Qloss_irr = 0.01 eta caldaia = 94.3 % Esercizio 2: hBFW = 1134 kJ/kg hSH = 3467 kJ/kg hRH = 3632 kJ/kg Dhis AP = 433 kJ/kg etais AP = 85 % GSH = 1000 t/h GRH = 800 t/h LHV = 25 MJ/kg eta GV = 93 % DhAP = 368.05 kJ/kg hRHc = 3098.95 kJ/kg DhSH = 2333 kJ/kg DhRH = 533.05 kJ/kg Qin CV = 766.5 MW Gcarb = 33.0 kg/s eta CV = 42 % Ppale = 321.9 MW Qcond = 444.6 MW Tcond = 40 °C Sgen = 0.123 MW/K DW = 35.49 MW Qcomb = 824.2 MW Deta I = 53.94 % Deta II = 4.31 % cp, aria = 1.0 kJ/kg/K DTaria = 15 °C Ga = 29638.4 kg/s varia = 0.81953 m3/kg Dp,aria = 50 Pa eta,tot = 0.65 Pel = 1868.4 kW DT1 = 25 °C DT2 = 10 °C DTmln = 16.4 °C U = 500 W/m2/K A = 54315 m2