Dear friends,

We are in the initial stages of the FEED for a sour gas facility (3.5 % H2S, 1100 psia). Our company has a recommended practice for equipment spacing. It says that the safety distances provided are the optimum. But, our consultant is recommending a risk based approach to define the plant layout. They have done some initial toxic release studies, and based on that they recommend that we expand the current layout to a bigger footprint, to ensure that the toxic risk levels are ALARP.

Could you please tell me how the other operating companies are addressing this issue of defining a plant layout, at the first pass? Specifically, I want to know - if its a sour gas facility, is essential to adhere to a risk based layout from the first pass itself? are there any standards available setting up the requirements for this risk based layout method?? Any help would be much appreciated.
thanks, Roshan