Soot accumulation has a great impact on exhaust gas economizer operational efficiency and safety. Soot deposits reduce economizer tubes thermal conductivity thus significantly reducing thermal efficiency. Accumulated soot deposits may ignite under certain conditions and damage the exhaust gas economizer. To reduce the risk of soot fire and keep economizer at maximum capacity following guidelines to be followed:
1) Keep the main engine combustion in good condition to reduce as much as possible any production of soot, while observing the following:
- Avoid any sudden change in the main engine load as far as possible.
- Keep the atomizer of the fuel injection valve in good order.
- During slow steaming, pay full attention to the condition of the main engine combustion.
2) Apply correct Fuel Treatment depending on the specification of the fuel oil:
- Carry out sufficient settling and draining of the settling tanks.
- Increase the frequency of cleaning the fuel filters
- Adjust the feed rate of the purifiers
- Select a suitable gravity disc for the purifier
When the use of fuel additives is recommended following fuel oil sample analysis, the fuel additives must be properly used according to the instructions of the ship manager.
3) Reduce accumulation of soot:
- To produce satisfactory results from the soot blower, always use the most powerful available pressure when steam or air soot blow is carried out.
- Monitor the draft loss value of the exhaust gas economizer, and carry out soot blow more often if any increase from the initial “draft loss value under non-fouled condition” is observed.
- During slow steaming, to produce satisfactory results from the soot blow, if possible, increase the main engine load to normal during the soot blow. Also, soot blow must be carried out more
- Regularly inspect the inside of the exhaust gas economizer in port, even when water washing has not been carried out, to monitor the accumulation of soot.
