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Showing posts with the label energy conservation & thumb rules in power plant

Thumb rules for power plant

BOILER: Boiler heating surface (M2) = Boiler capacity in kg/hr/(17–18)..Ex: 115 TPH boiler will have heating surface = (115 X 1000/17 or 18) = 6390 to 6750 M2 (Appx.)...... Boiler flue gas ducting size (M2) = Boiler capacity in TPH/15. No. of open tubes in steam drum for water recirculation = 30–31% of total no. of tubes present. Deaerator steam venting capacity = Deaeration capacity X 0.1%. Super heater safety valve relieving capacity at full open condition in TPH = Boiler MCR X 36–38%.......Ex: 125 TPH Boiler has SH safety valve of relieving capacity = (125 X 36/100) = 45 TPH. Drum safety valve (1 no.) relieving capacity at full open condition in TPH = Boiler MCR X 46–48%. All boiler safety valves (super heater and drum safety valves) relieving capacity at full open condition= Boiler MCR X 125–130%. Safety valves pop up pressure = Operating pressure X 106–107%.Ex: A boiler operating pressure of 110 kg/cm2 has safety valve set at 110 X 106/100 =116.6 kg/cm

Opportunities for energy conservation in power plants

    Energy conservation in Boilers: Control excess air in combustion which can lead to huge dry flue gas loss. Install online O2 analyzer for better controlling of excess air. Control Air pre-heater (APH) out let flue gas temperature, it is said that on every 22 °C rise in boiler outlet flue gas temperature leads to decrease in boiler efficiency by 1%. Optimize fuel moisture, which can lead to loss due to moisture. Installation of fuel (bagasse) driers for recovering potential heat from chimney inlet flue gas. Control unburnt in bed ash and fly ash, which can lead heat and fuel loss. Maintain maximum possible feed water inlet temperature at economizer inlet. On 6–7 °C rise in temperature of feed water at economizer inlet leads to 1% fuel saving. And 15 °C rise can lead to increase in overall thermal efficiency by 3%. Utilize unburnt from Economiser, bank zones by incorporating Cinder r