Nitrogen Purging of Walking Hearth Furnace

Hi Iris,

I'm thinking is it still require nitrogen purging if the furnace using Natural Gas instead of fuel oil?

Thanks!

Any of the following, depending on what was happening before and after the planned purge event did not take place:

• Smoke
• Failure to ignite
• Detonation without damage
• Detonation with rupture of pipework with the associated risk of injury/death
• Normal ignition and operation

Another question are the emissions to air readings through the smokestack, talking about environmental issues. Maybe, if not purged, a little excess of NOx content from normal readings can be identified, in adition to safety measures against explosion risks.

Using a Nitrogen (N2) purge instead of just air allows better control of the fuel-to-air ratio that is critical for safe and consistent, reliable burner operation.

I would think that the burner control would also require a N2 purge when the burner(s) are shut down/stopped so that live fuel could not get trapped in the piping and valves.

As stated by other posts; the purpose is to prevent uncontrolled ignition and/or explosions during the burner lighting and operation process.

I would highly recommend that you:

1. Thorughly review the burner control operation and philosophy documents.

2. Ensure all protective equipment and circuirty is operating as per QEM design.

3. Ensure that all correct startup and shutdown procedures are followed exactly by the operations and technicians at all times.

If you cannot get your management to support these recomendations and the other responses you have received to this issue, I would make sure that you and anyone that will listen stay as far away from the furnace area as possible at all times.

In fact it would be appropriate to make the call to OSHA and report the risk before you have to attend a funeral or funerals.

I have witnessed the aftermath of a boiler explosion in a power plant in the past and it is not something I would want anyone to ever be exposed to or to witness.