Stationary Gas Engine Exhaust System Design

[catserveng]

I'm looking for industry guidelines or standards, not manufacturer specific, for stationary industrial gas engine exhaust systems. Specifically, I need information regarding installation of back pressure or explosion relief valves on systems used in indoor applications.

I had a set of guidelines from the UK when doing some landfill gas engine projects a few years ago, but they are incomplete and nearly unreadable and a web search hasn't led me to anything like them. I also have seen information from some jobs in Denmark. In the US I haven't been able to find much of anything outside of one of CAT's Installation Guides and some older Selkirk info.

Any leads would be appreciated, thanks!

 

[Lou Scannon]

I don't know that universal or regional guidelines, not to say requirements]/i] exist. I can think of more than one industrial engine OEM that suffered an exhaust system "thermal event" in their development facility, in the past 5 years, which they were unprepared for, countermeasure-wise, that in one case resulted in many weeks of downtime for repairs; that in another, resulted curtailment of latitude for "development" activity during normal working hours, in a facility that was shared with production. Fortunately, in neither case, were any personnel injured or seriously jeopardized, but the respective affairs were taken very seriously indeed.
Other than what you already have to hand, you may be on your own formulating a design rulebook for system level explosion protection. I think the hardware is familiar enough - explosion panels, appropriately sized and placed. Ah, there's the rub...

 

[berkshire]

Catserve,
I am attaching a set of recomendations for the flour milling industry, for dealing with explosive atmospheres in blowing pipelines, conveyors etc.,whilst not directly related to engine exhaust pipes, it has a lot of information on back pressure relief and explosion relief systems. Hopefully it will give you some ideas.
B.E.

http://www.hse.gov.uk/food/dustexplosion.htm

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

 

[Hoxton]

For the UK, The closest you will come is IGE/UP/3 "Gas fuelled spark ignition and dual fuel engines" - UP = Utilisation Procedure
Published by the UK Institute of Gas Engineers.

http://www.igem.org.uk/

It is £101 = $US150!

Section 12 on exhaust systems suggests consideration of exhaust purge systems and / or relief panels.

The Environmental Services Association also has some useful guidance which is free.

http://www.esauk.org/reports_press_releases/esa_reports/ICoP2_-_Landfill_Gas.pdf

Basically, there is no "to do" book, a Competent Designer has to perform a Risk Assessment.

Some UK consultants specify NFPA, as there is no European equivalent to this (NFPA68, I think, but I do not have access to my server tonight.)

I have heard some incidents on older engines, but recent ones have better ignition fail detection etc. We also keep the ignition on until the engine has stopped (even with an emergency stop) to ensure that all gas in the inlet has been burnt up.. We also now inhibit the auto restart function after a failed start, as this could result in unburnt gas in the exhaust. We just leave it for a few minutes to allow any unburnt gas to dissiapate, before enabling a restart.


Bernard

 

[catserveng]

Thanks for the replies, the NFPA 68 was the one I was looking for, I just couldn't remember to title. The links to teh UK info was helpful too.

In general I've found that newer gas engines are much more reliable and less likely to have massive backfires. However, in the landfill and digester plants, especially during intial start, we struggle since getting the tuning and adjustments all working together sometime results is a noisy event.

Thanks again, Mike L.