The calorific value of ‘LPG’ (50% propane + 50% butane) is about ______________ kcal/Nm3? / Fuels and Combustion / By admin The calorific value of ‘LPG’ (50% propane + 50% butane) is about ______________ kcal/Nm3? A. 5000B. 25,000 C. 10,000 D. 15,000