16 07 18sol

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PROBLEM 1: combustion power 5000 kW biomass composition weight basis, % C 40,0% H 8,0% O 15,0% N 0,3% S 0,1% Ash 1,0% moisture 35,6% LHV, MJ/kg 15,0 MJ/kg ambient air T 35,00 °C air excess 0,70 flue gas T 140,00 °C flue gas cp/cv 1,33 ashes T 140,00 °C air molar ratio N2 3,76 O2 1,00 air molecular weight 28,85 kg/kmol air cp/cv 1,40 flue gas molecular weight 28,17 kg/kmol combustion efficiency 0,99 heat capacity of ashes 2,00 kJ/kg-K equivalent macromolecule xC 1,000 xH 2,400 xO 0,281 xN 0,006 xS 0,001 xH2O 0,593 Beta-O2st 1,460 kmol_O2/kmol_C alfa_air 11,37 kg_air/kg_bio FLUE GAS COMPOSITION stoic coeff concentration CO2, a 1,000 0,076022379 H2O, b 1,793 0,136333467 SO2, c 0,001 7,1271E-05 N2, d 9,338 0,709861382 O2, e 1,022 0,077711501 O2 concentration in FG 7,77% mass flow rate of fuel 0,3333 kg/s mass flow rate of air 3,7895 kg/s SOLUTION CxCHxHOxONxNSxS CxCHxHOxONxNSxS+(1+excess)*Beta- O2st*(O2 + 3.76 N2)--> aCO2+bH2O + cSO2 + dN2 + eO2 a, b, c, d, e from the atomic balance equations Beta_O2st = xC + xS + xH/4 - xO/2 xO2_FG = e/(a+b+c+d+e) m_fuel= 5MW/LHV; m_air=alfa*m_fuel; m_ash = m_fuel*y_ash; mass flow rate of flue gas 4,1195 kg/s mass flow rate ashes 0,0033 kg/s cp flue gas 1,19 kJ/(kg K) cp air 1,01 kJ/(kg K) useful thermal power 4423,95 kW boiler efficiency 88,48% x_SO2 0,000071 mg_SO2 / Nm3 203,50 x_SO2_dry flue gas 0,00008 x_O2_dry flue gas 0,08998 x_SO2_@6% 0,00010 mg_SO2 /Nm3_@6%_O2 294,48 flame temperature 1314,76 K 1041,61 °C feedwater pressure 30 bar feedwater temperature 150,000 °C feedwater enthalpy 633,8 kJ/kg from calculation for subcooled water steam pressure 20,000 bar steam temperature 400,00 °C steam enthalpy 3248,2 kJ/kg from Mollier diagram steam mass flow rate 1,69215 kg/s m_steam = Quseful/(hout-hin) m_air=alfa*m_fuel; m_ash =…