THE PROBLEM - 1) Aux Boiler windbox fire
Kindly be advised that aux boiler was in operation today for trying out discharge port pre-arrival checks on IGS and COPT plant.
For obtaining good oxygen content, aux boiler fuel oil pressure was increased to 3.5 bar which gave O2 of 9/%. After about two hour of operation, aux boiler windbox found becoming red hot.
Aux boiler was stopped immediately and fire fighting arrangement was kept stby.
After sufficient cooling down, boiler burner was opened up, found fuel accumulation in windbox had caught fire. Also as shown in attached photo, found large deposits of unburned fuel around burner assembly due to improper atomisation of fuel.
As informed earlier, burner rotary cup hub cover which forms the sealing between fuel and primary air side, has worn out considerably thereby allowing fuel to pass through to primary air side into windbox when fuel pressure is increased more than 2.5 bar. But at 2.5 bar fuel pressure, steam geneartion is about 3-4 bar pressure which is not good enough to run the cargo pumps.
Operating boiler burner in this condition may lead ontowed incident on the boiler and may also damage the newly installed water tubes due to localised heating.
THE SOLUTION - 1) Aux Boiler windbox fire
MUIRA BOILERS - AUTOMATION