PURPOSE: To recover the oil component from an oily sludge, safely, rapidly and economically, without using an extraction solvent, by heating and melting the sludge to separate the coarse contaminant, and circulating the fluid free of the contaminant.

CONSTITUTION: The oily sludge stock is supplied to a disintegration means 3 composed of steam pipes through the inlet 2. The sludge S brought into contact with the wall of the steam pipe 3' is immediately molten and disintegrated (broken). The coarse contaminants existing in the sludge S is left on the disintegration means 3. The molten sludge S' free of the coarse contaminants falls to the agitation and extraction zone 4, and is forcibly circulated with the oil circulation pump 11 through the chamber 9, the connecting pipe 10, the oil vecovery zone 5 and the extraction zone 4. A part of the recovered oil in the oil recovery zone 5 is extracted and discharged with the pump 14. The coarse contaminants left on the disintegration means 3 and the tray 6 are transferred intermittently to the basket 15 in the chamber 9.