I use a belt driven vacuum pump from a dairy barn to supply vacuum to an old anhydrous ammonia nurse tank (a residential propane tank on wheels). The pump will pull 24" of vacuum when completely deadheaded--I leave a valve cracked to allow some air to flow through to keep the vacuum pump cool. These tanks hold just over 1000 gallons.

I use this set-up to gather used oil for burning in our shop heaters. 18-20" of vacuum in a 2" hose will empty a 55 gallon barrel in about 3 minutes--I have a valve at the end of the suction hose because if the suction hose becomes empty (sucking air only) it will collapse the 55 gallon drum. The small bung will not allow enough air inside the barrel.

To empty the oil from the NH3 tank we put 20 psi of regulated air in the tank and fill the oil heater tanks. We try to bring the tank inside overnight so the oil will be warmed up when it is time to fill the heaters. This system works very good for us.

Remember 9-11-01--God Bless the USA
JUSTICE, not REVENGE, will prevail

1951 Chevy 1/2-ton Pickup truck