In a boiler test 1250 kg of coal is consumed in 24 hours. The mass of water evaporated is 13,000 kg and the mean effective pressure is 7 bar. The feed water temperature is 40°C, the heating value of coal is 30000 kJ/kg. The enthalpy of 1 kg of steam at 7 bar is 2570.7 kJ. Equivalent evaporation per kg of coal is_____.