op9
Industrial
- Aug 18, 1999
- 111
Hi All,
I have to investigate a fault next week on board a ship where they have an Aarlborg oil fired boiler (Danish). The burner is steam atomised operating at approx. 15MW (50 MM Btu/hr)max. The problem they are having is that they are emitting small carbon/ash balls out of the stack when the burner is on HFO. (see attached photo). They are soft, light and hollow. The stack appears clear from a distance so no visual smoke. When they operate on light oil with air atomising, no problem. I have not worked on this burner before. The ships engineers report that they have tried all sort of adjustments which sometimes appear to fix the problem, but it soon returns. Obviously atomising fuel temp/pressures, steam pressures etc need to be correct, but I am assuming that they have made sure that is as per the manual.
I am "guessing" from the shape of the carbon that there may be a problem that the atomising steam is wet and that the "balls" are due to water droplets in the flame attaching to burning fuel which cools and stops the combustion process producing carbon, the water evaporating, hence the hollow structure.
Would appreciate any comments, especially if this phenomenon has been experienced before.
Thanks in advance,
Rod
Rod Nissen.
Combustion & Engineering Diagnostics
I have to investigate a fault next week on board a ship where they have an Aarlborg oil fired boiler (Danish). The burner is steam atomised operating at approx. 15MW (50 MM Btu/hr)max. The problem they are having is that they are emitting small carbon/ash balls out of the stack when the burner is on HFO. (see attached photo). They are soft, light and hollow. The stack appears clear from a distance so no visual smoke. When they operate on light oil with air atomising, no problem. I have not worked on this burner before. The ships engineers report that they have tried all sort of adjustments which sometimes appear to fix the problem, but it soon returns. Obviously atomising fuel temp/pressures, steam pressures etc need to be correct, but I am assuming that they have made sure that is as per the manual.
I am "guessing" from the shape of the carbon that there may be a problem that the atomising steam is wet and that the "balls" are due to water droplets in the flame attaching to burning fuel which cools and stops the combustion process producing carbon, the water evaporating, hence the hollow structure.
Would appreciate any comments, especially if this phenomenon has been experienced before.
Thanks in advance,
Rod
Rod Nissen.
Combustion & Engineering Diagnostics