Abstract: A finished oil product is recovered from crude or waste oil contaminated with water and the like by heating the waste oil in a tank with a heating flame which may be gas or oil fired. The waste oil is heated until vapors including light ends and the desired finished oil product are produced from the waste oil within the tank. The vapors are introduced into the heating flame so that additional heat is developed by such afterburning to heat the waste oil in the tank. The finished oil product as recovered from the waste oil is discharged from the tank by a suitable outlet pipe arrangement.