Switchroom in Fertilizer Industries

Use explosion proof motors and switchgear. Fans should also have explosion proof motors for venting enclosures. DO NOT USE ELECTROSTATIC FILTERS. There are many wrong ways, but only one right way. Additionally, all tools used should be spark proof; flooring should be static resistant; even the clothes you wear. There are standards that must be followed for environments that may be potentially explosive.

What, in a switchroom?

The site has a serious process materials containment problem. Solve that problem first.

Next, have a potentially explosive atmospheres zoning drawing created by a Chemical Engineer that is practised in these things.

If the switchroom is inside any hazardous area zone after that step, do not energise it. Rebuild it outside the zone instead.

Ok friends

Thanks a lot for your comments, before close this case I would like to let you know as follow: I'm pesuaded it is a very delicated issue to be solve in a forum, but my intention was just share ideas about this matter.

The actually in fact is that I have to define a proporsal project from bidder that are considering switchrooms building placed in hazardous areas as common practice in all fertilizer plant (IEC-60079-13) just to find the load center as all of your know.

The whole hazardous zones are full evaluated as per correspond to different gases that could be present in each zone in particular (zones 1 & 2).

Referent to cable trench, my proporsal was sand filled and cable trays with ROXTEC at all cables trays entries.

The point is that bidder proposed the switchrooms only provide with pressurized, rejecting the installation of air conditionig too. I think they are making a mistake ignoring the air conditionig because this action could leads to equipment damage due to lack of humidity control therefore the condentation will damage the internal installed electrical equipment.

Bye

http://cr4.globalspec.com/thread/84390/Texas-Fertiliser-Plant-Blast

Which plant...??

NH3

As a minimum bring in an air supply line/duct from outside the HAZ (hazardous air zone) and make sure the building is accessed via an airlock to maintain positive pressure in the building. I would assume it's a totally enclosed concrete block building with no windows as a starter. You can heat or cool the air as it comes in and vent it as needed through a vent stack well above roof level.

Should I can use pressurized, air conditioning or both method to prevent switchroom gas penetration into this local.

It depends on what the switchboard room is zoned as. Get someone qualified to zone the areas of the plant first before you proceed any further. Air conditioning is not a form of hazardous area protection and neither is pressurizing an entire switchboard room to make it into a safe area.

In fact your main switchboard room should be in the safe area, with distribution switchboard(s) located in the hazardous areas being Ex ed (or similar).

Also, how to avoid gas penetration into sitchtroom though cable trench and cable trays entries

You need to seal the holes and cables to prevent gas passing from one zone to another, especially from a hazardous area zone to a safe zone. This can be done with cable glands, barrier glands, special sealing compound, etc. It depends on the cables, the zone, the application, etc.

More information can be found in the applicable IEC 60079 (or similar) standards for cable installations.

Try talking to a hazardous area equipment supplier directly like Stahl.