Alternatives of Oil/Sand in Tank Ring Wall Foundations 1

[CUTIGER90]

I know that using a fuel oil-sand mixture is not an environmentally friendly solution anymore inside ring wall foundations. One viable option that I have seen is a liquid asphalt-sand mixture. However, in this case, a suggestion has been made to use a vegetable oil-sand mixture because where we are located, we have an ample supply of vegetable oil at our disposable. Has anyone ever heard of doing anything like this before? My concern is that the properties of the vegetable oil mixed in the sand will not produce the same slope stabilization affects as the liquid asphalt. Are there any suggestions or other concerns here?

 

[JedClampett]

I've heard of it. We'd do it more, but the vegetable oil was much more expensive than the other oils. If you have access to a supply and the cost is not prohibitive, I'd use it.
When you think about it, why is putting oiled sand under a tank environmentally evil, but using asphalt on roads is OK? They're basically the same.

 

[CUTIGER90]

Thank you JedClampett for your reply. One other item here though. I have some spec information that states that the dry sand mix ratio shall be about 120 Lbs. of SC-800 Liquid Asphalt to 1 ton of sand. It appears that the Specific Gravity of the liquid asphalt and the vegetable oil are very close. I would assume that I could use the same mix ratio with the vegetable oil as the liquid asphalt. Any thoughts here?

 

[JedClampett]

Sorry, CUTIGER90, that's a little more specific than I'm knowledgeable of. It makes sense to me. But I'm sure someone knows.

 

[JStephen]

With the vegetable oil, you'd need to consider if it actually does anything to prevent corrosion, and if it's actually okay to dump on the ground. I don't know that I've seen a definite answer to either question, which would make me hesitant to pay a premium to use it for that purpose.

NFPA-22 mentions using lime as an alternative, and a cathodic system can also be used. They also make tank pad products as a replacement for oil sand. I don't know that slope stabilization has anything to do with it if it's inside a ringwall.

 

[JedClampett]

I'm not sure the vegetable oil prevents corrosion. I think it replaces the moisture in the sand and makes it a little easier to work on.
We've put down aggregate base and had the bottoms of steel tanks corrode very quickly. I'd like to think the oil would of helped.