Coal-fired boilers are applied in various industries for the industrial and civil uses to generate steam and hot water. The steam is mainly used for production and the hot water is mainly used for heating and daily use.
The gas-fired hot water boiler heats up quickly and has the high thermal efficiency. It is widely used in the heating industry and production. What are the maintenance methods of the gas-fired hot water boiler?
There are many applications of hot water boilers. With the environmental protection requirements become stricter, the hot water boilers are mostly gas-fired. Therefore, it is important to know how to use the gas-fired hot water boilers safely and what are the maintenance methods.
1) Set up the air preheater. One of the most effective measures to improve the thermal efficiency of thermal oil heater is to use an air preheater for heat recovery. 2) Use waste heat boiler for heat recovery. The waste heat boiler uses the waste heat in the flue gas exhausted from the thermal oil heater to heat water or generate steam.
A water level sensor fail on a steam boiler is extremely dangerous. The low water cut of should be tested daily. If the sensor fails the boiler could turn all the water into steam, leaving the boiler dry. Without water in the boiler the flame from the burner would heat up the heating surface to extreme temperatures and would crack and damage the inside of the boiler. But that’s not the dangerous part. If water added to boiler while it is extremely hot. Once water touches the extremely hot heating service, water would immediately start to evaporate into steam. When water evaporates it expands 18x it’s original size. The boiler would explode from the sudden increase in pressure from the inside. Some in some cases, boilers that have exploded out of a building and have landed 100s of feet away.
There are many opinions on the best way to clean a steam boiler. One of the oldest ways is to dissolve a pound of tri-sodium phosphate (TSP) and a pound of caustic soda (lye) in water and pour it into the boiler. Let it cook for a few hours and then drain the boiler. If you can't buy TSP in your town, try a commercial soap called MEX. It works well and will not damage the rubber gaskets found in some boilers. However, before you clean any boiler, check the manufacturer's instructions for their recommendations.
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℃.
If the final temperature of feed water doesn’t reach the saturated temperature after being heated by an economizer, (that is, the feed water has not reached the boiling state), we call the economizer as a nonsteaming economizer. Generally, the final temperature is 30-50℃ lower than the saturated temperature.
