Condensate Recovery Saving
A plant returns 15,000 kg/h condensate at 90°C instead of using make-up water at 30°C. Calculate sensible heat saving using cp=4.187 kJ/kg·K.
Read lesson →Knowledge Library
Archives: Numericals
Air-Fuel Ratio
A furnace burns 1,000 kg/h fuel with 18,000 kg/h actual air. Calculate actual air-fuel ratio. If theoretical air is 14 kg/kg fuel, calculate excess air.
Read lesson →Chimney Draft
Calculate approximate theoretical draft in mm of water for a 40 m chimney when outside air density is 1.20 kg/m³ and average flue-gas density is…
Read lesson →Economiser Heat Recovery
Feedwater flow is 20,000 kg/h and temperature rises by 45°C. Take specific heat as 4.187 kJ/kg·K. Calculate heat recovered.
Read lesson →Blowdown Percentage
Feedwater flow is 52 t/h and steam generation is 50 t/h. Neglect other losses. Calculate blowdown as percentage of feedwater.
Read lesson →Fuel Required for Steam Generation
Find fuel required to generate 12,000 kg/h steam when enthalpy rise is 2,300 kJ/kg, fuel CV is 40,000 kJ/kg and boiler efficiency is 80%.
Read lesson →Equivalent Evaporation
A boiler evaporates 8,000 kg/h from feedwater enthalpy 420 kJ/kg to steam enthalpy 2,760 kJ/kg. Calculate equivalent evaporation from and at 100°C using latent heat…
Read lesson →Boiler Efficiency by Direct Method
A boiler generates 10,000 kg/h of steam. Enthalpy of steam is 2,780 kJ/kg, feedwater enthalpy is 420 kJ/kg, fuel consumption is 750 kg/h and calorific…
Read lesson →