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Ggas in turbina potenza design 20 kg/s Dati cp gas 1.10 kJ/kgK Assunzioni Tgas in turbina potenza design 700.0 °C pgas in turbina potenza design 4.00 bar xO2 0.14 xCO2 0.04 xN2 0.74 xH2O 0.08 Dh°f C3H8 -104.60 kJ/mole Dh°f CO2 -393.51 kJ/mole Dh°f H2Ovap -241.82 kJ/mole Dh°f H2Oliq -285.80 kJ/mole MMC 12 kg/kmole MMH 1 kg/kmole MMO 16 kg/kmole MMN 14 kg/kmole Tamb = 25.0 °C Tacqua surr,in = 90.0 °C Tacqua surr,out = 120.0 °C Efficacia scambiatore = 0.85 eta_ref,el = 0.55 eta_ref,th = 0.90 Qcomb_TG = 15000 kWLHV Ggas off design = 15 kg/s T_Gas post-comb = 800 °C a) MMgas = 28.4 kg/kmole R = 8.314 kJ/kmol/K R = 0.293 kJ/kg/K cv = 0.807 kJ/kg/K gamma = 1.363 TOT_is/Tin_TurbPot = 1.45 Tin_TurbPot = 973.15 K TOT_is = 672.90 K eta_is = 0.85 TOT = 717.94 K TOT = 444.79 °C eta_mec-el = 0.97 Pel = 5446 kW b) Ds = cp*ln(T2/T1) - R*ln(p2/p1) = 0.071 kJ/kgK Tamb = 298.2 K DEx = 21.25 kJ/kg DEx = 424.95 kW c) Tmin fumi camino = 90.00 °C DTmax fumi = 354.79 °C DTfumi = 301.57 °C Tfumi camino = 143.22 °C Qutile = 6634.6 kW eta_th = 0.442 eta_el = 0.363 PES = 0.132 d) G_rid=G*(RT)^1/2/p = cost T=cost ---> p_offdes = p_des*G_offdes/G_des = 3 bar TOT_is/Tin_TurbPot = 1.34 TOT_is = 726.4 K TOT = 763.4 K ~ TOT = 490.3 °C Pel = 3356 kW e) C3H8 + 5O2 -> 3CO2 + 4H2O Dh°comb = -2043.21 kJ/mole MM C3H8 = 44 kg/kmole PCI C3H8 = 46.44 MJ/kg f) Gcomb*PCI + GgasTG*cp_gas*(TOT-Tref) = GgasPC*cp_gas*(Tfiamma -Tref) Ggas_PC = GgasTG + Gcomb --> Gcomb = 0.171 kg/s g) Mcomb = 0.00390 kmol/s Mgas_TG = 0.704 kmol/s MCO2_PC = 0.0399 kmol/s MH2O_PC = 0.0719 kmol/s MN2_PC = 0.5211 kmol/s MO2_PC = 0.0791 kmol/s Mgas_PC = 0.7120 kmol/s xO2_PC = 0.111