The Effect of Pressure on Oxidation Kinetics of Tar From a Tarmat Reservoir

Abstract

The oxidation kinetics of a tar with physical and chemical characteristics similar to those of a reservoir tar were studied employing a variable-temperature oxidation reactor. Mixed with clean, loose sand, the tar showed oxidation behavior typical of heavy crudes with LTO and HTO peaks in oxygen consumption. Higher pressures caused larger LTOoxygen consumption, lower HTO-oxygen consumption, lower HTO-peak temperatures, higher apparent H/C ratio of fuel, and lower HTO activation energy. All these effects are attributed to suppression of light-end evaporation at low temperatures. Compared with clean sand, natural crushedcore material promoted LTO of the tar but did not alter HTO parameters significantly. With HTO-peak temperatures and activation energies above 500 C and 100 kJ/mol, respectively, the tar is not expected to provide for sustained in-situ combustion in the reservoir. 113