Venting sumps

[hardworking]

A friend of mine that is still in the business told me a customer is installing a 4" FG line into and out of each sump, running them (feed in to the 1st sump and feed out of the last sump) to the top of the canopy and installing a blower on one line. The idea is to vent the acidic by-product of having Ethanol in the gas.

Anyone else running into this? Does it help?

Sounded like an interesting topic.

[ZMiller]

I'm puzzled as to why vapors are in the sump(s) in the first place. If the tanks are pressure decay tested using ARB protocol (2-inch WC) they pass. If the same tested to San Diego (10-inch WC) they might very well fail. A fail generally means something somewhere in the system is leaking. Ethanol being the suspected problem constitute one would think corrosion issues would have been seen in sumps when ethanol as an oxygenate was blended (California) into gasoline in the early 1990's.

The problem may be more an EVR issue where tanks are becoming at one time or another over pressurized. 5, 6 and higher psi during an out of compliance bulk delivery is common. If one pressurizes a UL58 rated tank, fittings and associated sump fueling component ullage connections will leak.

The low PH condition issues in sumps has become an integrity and catastrophic release issue. One might think problem symptoms would be better and more economically addressed identifing and resolving the actual problem of why vapors are migrating from the tank into the sump.

[CherokeeUST]

It sounds feasible. But would this then have to be regulated by the local Air regulators, much as a stage II vapor recovery system is?

[hardworking]

It sounds feasible. But would this then have to be regulated by the local Air regulators, much as a stage II vapor recovery system is?

That is an excellent question (one I did not think to ask that project manager).

[ZMiller]

Venting sumps to the canopy. This is not an April fools joke or question is it?

[hardworking]

Venting sumps to the canopy. This is not an April fools joke or question is it?

No, but I can understand this question,

I heard about this about a month ago. Your comment about vapor leaks on the tank is a good one (early post).

[rides426]

I work for a company that has 100 stations. I would love to install a ventilation configuration on my stations. We have tons of problems with residual moisture and vapor in the sumps.

[rides426]

A friend of mine that is still in the business told me a customer is installing a 4" FG line into and out of each sump, running them (feed in to the 1st sump and feed out of the last sump) to the top of the canopy and installing a blower on one line. The idea is to vent the acidic by-product of having Ethanol in the gas.

Anyone else running into this? Does it help?

Sounded like an interesting topic.

Where Can I go see the installation?

[justinforman]

In vaulted tank sites they have blowers keeping constant air flow in all the vaults, I don't see why this couldn't work with a standard UST setup.

[ZMiller]

Will some bright person tell me why there are vapors in the sumps in the first place?