It could also say, how much heat is required to rais the water temperature from 60 ℃ to 90 ℃.
To calculate heat required follow below steps
Q= mCp dt
Where
m - water flow rate (kg/hr)
Cp- specific heat of water
dt- temperature differences ( 90–60)
You will get heat required in kcal/ hr.
dividing to Q by fuel GCV and system efficiency you will come to know how much fuel (either it is coal or oil) required to raise the temperature of water from 60 ℃ to 90℃.
For same energy output when energy input is lesser efficiency increase. When maximum heat energy is generated from coal or losses in heat transfer are reduced efficiency increase. Coal in boulder size is burnt combustion may not be complete. There will be more unburnt coal. As per coal chemistry and as per boiler flue gas velocity as designed best coal size for full combustion is designed. Maximum crushed coal is also not the best. Then there will be more coal dust. According to general design in various technologies pulverized coal give best combustion for fbc boilers. For cfbc boilers generally crushed coal size is 6 mm.
When you achieve best combustion mean this is main contributor for increase in efficiency. Boiler design, heat transfer, flue gas velocity, heat losses, are other factors for efficiency.
Boiler efficiency is mainly depended on the amount of losses in the system. In high capacity pulverized coal fired boilers the total losses account to about 12 to 14%. Roughly 50% of the losses are governed by fuel properties like hydrogen in fuel, moisture in fuel and ambient air conditions. The other 50% losses are carbon loss and dry gas loss. The best efficiency in the boiler can be achieved if the losses are kept to the minimum. Since 50% of the losses are dependent on the fuel and ambient condition, the best efficiency can be achieved by properly tuning the other 50%, i.e. mainly carbon loss and dry gas loss.
The following conditions will occur when a gas-fired boiler is leaking:
The working pressure of natural gas changes.
There is a strong airflow sound near the source of the leak.
The hand-held alarm makes an abnormal sound.
If the boiler has a serious leakage, the fixed alarm will issue an automatic alarm and the exhaust fan will be opened automatically.
In the work of transforming a coal-fired boiler into a gas-fired boiler, the principle of changing the original boiler should be reduced without changing the pressure component of the boiler body. The transformation process should focus on the choice of gas burners, the determination of the number of burners, the layout of the burners, the matching design of the furnace layout, and the selection of explosion-proof measures. Step by step, both economic benefits and practicality should be considered.
Biomass fuel can be applied to a biomass-fired boiler by treatment and compression molding. Commonly used are straw particles, rice husk particles, wood particles, sawdust particles, peanut rod particles, sugar aldehyde residue particles, palm shell particles and so on.
The coal-fired boiler refers to the boiler uses various types of coal as fuel and converts the heat of coal to steam or hot water.
There are generally two calculation methods of the circulating water volume of a coal-fired hot water boiler. One is to calculate the hourly water volume of one square meter and the other is to calculate the design parameter volume of every ton. As for the make-up water volume of this type of boiler, it is usually calculated as 1% to 3% of its total circulating water.
Four factors are related to the failure of the draft fan of the biomass-fired boiler. The factors are electric, electrical motors, dampers and induced draft fans. Therefore, if the draft fan breaks down, you can check the electric and electrical motor first, then you can check the damper and the induced fan.
