Q & A > Question Details
Does any regulation / Code of practice calls for 300 lb rating Piping around AMMONIA storage tanks (liquid piping and Vapor piping)? Although the operating pressure in the vapor lines is around 500 mm WC , piping used is 300 pound rating
Is it mandatory to size the PSVs of ammonia storage tank for fire case? Ammonia shows little affinity towards fire due to very narrow range of LFL and UFL.
 
Answers
23/12/2013 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
I can't speak to the code or regulatory side of ammonia plants. I really just wanted to clarify one point. Fire cases for PSVs are not based on the flammability of the liquid being relieved. Rather they are sized based on the amount of vapor that can be generated by a fire external to the vessel. My background is petroleum refining where there is always the risk of fire, so there pretty much all PSVs have a fire sizing case. I don't know what the practice is in the ammonia industry.