This article is all about How soot blowing in Boiler is done ?
What is soot blowing ?
A soot blowing is a procedure of removing the soot built up on the surface of pipe when hot exhaust gas pass through it. or, we can simply define it as – the process of removal of soot deposits exhaust gas passing tubes with the help of steam or air. It is done by a device name called soot blower.
Note : – On ship soot blowing of boiler is done two times a day.
What is the purpose of soot blowing ?
If we do not do regularly soot blowing then with times soot deposits on the surface of tubes. It made very hard surface and not good conductor of heat. So. heat will not transfer to water for conversion into steam. This soot has flash point 1000 degree celcius but If any how it get wet , its flash point decrease and cause fire. There are so many disadvantages like – Heat transfer will decrease, boiler efficiency decrease, EGB fire.
On ship Soot blowing is done on middle of ship through steam. On middle of ship , we mainly use EGB.
On port, main engine not run so , we do soot blowing of boiler through air. Modern ship, it is done by some chemicals with air.
Soot Blowing procedure of Economizer through steam
For Soot Blowing, You have to inform Bridge first and check the directions of wind.
Check the steam pressure of boiler and also check the temperature of Exhaust Gas Boiler ( EGB ).
If pressure steam of boiler is less then increase the boiler pressure. To increase Boiler pressure Increase the firing or best option is close the steam line of Tanks Like waste oil tanks etc.
If your Boiler pressure is around 10 bar the start doing soot blowing ad do it up to to when your boiler pressure reach to 6 -7 bar.
After Completion of soot blowing, make ensure that steam pressure of boiler slowly increase ( efficiecy of boiler ) and temperature of EGB should decrease.
Note : _After soot blowing pressure decrease means your feed pump left taking suctions from cascade tank. And temperature of egb increase means there is EGB fire.
Soot Blowing Procedre
- First open the Drain valve and everything is clear then close the drain valve.
- Open main steam line valve which go to steam pipe in egb for soot blowing.
- Open drain valve nearby of main steam valve and after few second close it.
- After that open Valve one by one open soot blow valve and close after 20-30 seconds. Open Soot blow Valve Diagonally ( Valve ).
- Finally close the main valve.
When we open the soot blow valve it passes through Soot blow pipe which is in exhaust pipe of egb. There is so many holes on pipe and steam come through it and clean the soot on exhaust pipe. In old ship EGB, pipe is rotated manually.
Soot Blowing through Air
Same procedure you have to inform the bridge and take the directions of wind ( Fire hazards ).
Raise the boiler pressure ( How to raise the boiler pressure already mention above ).
Open the drain valve until soot blow pipe drain clear.
Now, open the soot blower valve and increase the air to the boiler is 50 % more.
Now open the steam valve and do it by turning the wheel ( open or close ) to 20-30 seconds.
Then close the steam valve and the main soot blower valve.
finally open the drain valve and close it.
Note :- some of point must be noted during blowing of soot.
- Must check the directions of wind . It causes fire hazard.
- Do not do it for long time.
This is all about blowing procedure of soot blowing. If you like my content, Do not forget to share it.