Furnaces explosions are not uncommon in the marine industry. It is important that boilers be operated in strict compliance with the manufacturers’ recommendations and regulatory and code requirements.
A furnace explosion is usually the result of ignition and instantaneous combustion of highly flammable gas, vapor, or dust that has accumulated in a boiler. The effect of the force from the explosion is often much greater than the boiler combustion chamber can withstand.
Minor explosions, commonly known as deflagration, puffs, flarebacks, or blowbacks, may suddenly blow flames from firing doors and observation ports. Anyone in the path of a flame, which might extend many feet, may be seriously burned. An increase in the intensity of the explosion would naturally increase the probability of a serious accident.
Furnace explosions may be avoided by taking reasonable precautions:
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Ensure that fuel inlet valves on non-operating burners and ignitors are tightly closed and do not leak.
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Ensure that Forced Draft and/or Induced Draft fans and burners are in good operating order and condition.
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Purge the furnace in accordance with the manufacturer’s specifications each time before the first burner is ignited.
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Ensure that the ignitors, fuel regulating controls, and flame safeguards operate as required.
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Ensure that there are no contaminants in the boiler’s fuel system.
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Ensure that the fuel/air ratio is in accordance with the manufacturer’s specifications.
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Remove oil guns from idle burners after closing the oil and air or steam supply valves when shutting down oil burners. Drain and clean residual oil from the guns before storage.
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Never use the boiler’s soot blowers to blow soot in a cold boiler.
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Ensure that limit and operating controls are in good working condition and are not "by-passed" or "jumped-out".
Proper operation, proper maintenance, and timely inspections are key elements in ensuring safe boiler operation.
