Several treatment methods could be found to deal with waste oil, and can be in turns of direct or indirect re-use at the final stage.

As to direct re-use, waste oil usually is treated as RFO (Recovered Fuel Oil), and blending with virgin fuel oil as fuel for the Power Plants and Road Stone Industry, or to spray on low caloric coal at Coal-fired Cement Kiln or industrial furnaces.

As to indirect re-use, 2 main stream processes are available. One of them is using thermal cracking or solvent extraction technology to covert waste oil to diesel-like- fuel oil, and the other one is recycling waste oil to base oil.