Underground Sewer System in Refineries? 1

[frcreek]

A common practice in designing a refinery is to use underground sewer system?

Can a refinery be designed without it?
Any safety issue, if it's not considered?
Any alternative design to avoid it?

thank you,

 

[mbeychok]

.
(1) A common practice in designing a refinery is to use underground sewer system?

I have seen it done in many refineries

(2) Can a refinery be designed without it?

How would you deal with oil spills, leaks and drips, washdown of equipment, rainfall, etc., etc.?

(3) Any safety issue, if it's not considered?

I would think that oil spills, leaks and drips and any other oily substances on the ground surface would create a definite fire hazard


Milton Beychok
(Visit me at www.air-dispersion.com)
.

 

[ppmsb2008]

Hi,

In our 200KBPSD refinery we have few underground systems:-
1) Oily Surface Water
2) Oily Water Sewer
3) Sanitary Sewer
4) Fire Water System

ppm

 

[JJPellin]

When I came to work in our 300,000 BPD oil refinery, we had lots of underground piping. Specifically, we had oily water sewer, storm sewer and sanitary sewer. A few years ago we were required to eliminate the underground oily water sewer. We did this by building a trench system with the sewer pipes in the trench. That way we have secondary containment if the pipes were to leak and the pipes are accessible for inspection. The storm sewers are still buried, but they have to go to diversion boxes that capture any dry weather flows and divert them to our waste water treatment plant. We have extensive requirements to protect the storm sewers from any contaminated flows. If any water other than rain water, well water or demineralized water contacts the ground or flows to the storm sewer, it must be reported to the state environmental regulators. We have been granted the ability to back-flush cooling water exchangers to the storm sewers only under special circumstances. The main safety concern with any underground sewer system is to protect against the accumulation of combustible mixtures of hydrocarbon and oxygen. This is accomplished with water traps, primarily.

Johnny Pellin

 

[frcreek]

Thank you guys for the info,