supply of excess, air

supply of excess coal

burning CO and unburnts in upper zone of furnace by supplying more air

fuel bed firing

inherent moisture and surface moisture are different things

in some coals moisture may be present upto 40%

some moisture in coal helps in better burning which is not possible with completely dry coal

it increases thermal efficiency

cavitation of .boiler feed pumps

corrosion caused by oxygen

heat transfer coefficient

pH value of water

100 kg/cm2 and 540°C

1 kg/cm2 and 100°C

218 kg/cm2 abs and 373°C

218 kg/cm2 abs and 540°C

increases

decreases

remains unaffected

first increases and then decreases