How long does it take to empty a 55 gallon drum?

Answer 1

That depends on:

-- how full the drum is before the emptying begins

-- whether the contents of the drum are comprised of water, oil, or molasses

-- the temperature of the contents

-- whether the drum is emptied by a pump or by being tipped

-- if by being tipped, then the angle of tippage

-- the size of the egress port

-- whether a make-up air hole is also provided.

The question includes none of this information.