A flame appear at economizer coil during running of main
engine and EGB is put into service with circulation of water is called economizer
fire. Various reasons for economizer fire are
- Due to soot deposits on economizer coils. Soot deposits are high while using high carbon content fuel
- At maneuvering time, incomplete combustion may occur and at that time flue gas velocity is low thus unburned fuel can adhering on economizer coils.
- Air carry through exhaust gas due to excess supply of scavenge air
- Flame is produced when air an fuel are proportionally mixed in the sufficient heating temperature
Indications of Economizer Fire
- Overheating And peeling of paint at economizer body
- Sparks emit from the funnel
- Sudden increase in uptake gas temperature
- Flame visible in the smoke indicator
Actions in Case of Economizer Fire
- Inform bridge and C/E, start stby A/E prepare for engine slow down
- Slow down main engine and stop the engine if possible.
- Cover the Turbo Charger
- Soot blow to be carried out to blow off the soot, always keep an eye on temperature
- Never soot blow while economizer on fire and temperature above 600 degree, it can cause hydrogen fire and melt down the coils stack.
- Continue running circulating pump. Keep an eye on pump pressure.
- If fire fighting equipment if fitted on economizer it should be put in operation
- Spray water on external casing of the uptake to cool the affected area
- Few times starting and stopping of main engine also helps to blow out collected soot at the uptake
After fire is out
·
After cooling down to ambient temperature open
the economizer cover
·
Clean the inside parts of economizer
·
Check the tubes for any damage if any repair it
When soot fire happens we will inform bridge that's right but first we will slow down the engine. The steam is allowed to dump to reduce the temperature of economiser. Soot blow is carried out to blow off the soot. But we have to keep an eye of uptake temperature. Soot blow should be stopped if temp rises beyond 600. Then if the soot fire stops then engine rpm can be increased slowly but if not better to stop the engine . Fire fighting equipment is provided should be used and outer surface should be a boundary cooled. After fire stops let the economiser cool down and then opened up for inspection.
ReplyDeletewell said..
DeleteCOZ IF THE TEMPERATURE GOES BEYOND 600 DEGREES nd reachs around 900 or 1000 degrees then the real problem comes that is the Hydrogen fire. coz at temperatures 1000 degrees the chemicl reaction takes place and water molecules break to form HYDROGEN and CARBONMONOXIDE. and these two gases are combustible. KABOOOOOOMMMMMMMMMMMM
DeleteIf 30% tube is damaged and there is no bypass system for the Economizer, what action to be taken to safely reach the next port.
ReplyDeleteAnyone, please guide me.