air tank for vacuum

I need a way to vacuum hot oil without collapsing a vessel. We have been using

55 gallon drums for oil that has cooled down, but, they will collapse when enough hot oil is vacuumed into them. My thought was to use a 20 gallon, 200 psi, 650 degree F rated air tank. This would not be a true vacuum. There will be constant air flow. The hot oil that we need to vacuum is only about 1 to 1 1/2 inches deep, so, a standard hot oil pump will not work.