Propane deasphalting

The propane deasphalting process(PDA) is a petroleum process for processing heavy oils. The principle is that propane is used as a solvent to extract the heavier fractions from the reduced pressure residual oil (and sometimes from the atmospheric residual oil) obtained by distillation of crude oil to produce deasphalted oil as a raw material for heavy lubricants or as a raw material for cracking; the non-ideal components such as gums and asphaltenes are present in the deasphalted asphalt. The deasphalted oil is further refined by solvent refining, solvent dewaxing and hydrofinishing (or white clay refining) to produce high viscosity lubricant base oils. It can also be used as a feedstock for catalytic cracking and hydrocracking. De-oiled bitumen is used to produce road asphalt or construction asphalt, and also as a feedstock for viscosity reduction cracking to produce fuel oil.