Experimental investigation of in situ upgrading of heavy oil by using a hydrogen donor and catalyst during steam injection

摘要

Experiments were conducted to investigate the feasibility of in situ upgrading ofheavy oil by the use of an orgametallic catalyst and a hydrogen donor (tetralin). Theexperiments used a vertical injection cell into which a mixture of sand, water, and Jobooil was thoroughly mixed and packed. Two types of runs were conducted: a run wherethe tetralin and catalyst were mixed within the mixture before packing into the cell, andthe other was conducted by injecting a slug of the tetralin-catalyst solution beforecommencing with the steam injection. The Jobo oil used had an oil gravity of 12.4? APIand a viscosity of 7800 cp at 30?C. The injection cell was placed in a vacuum jacket andset to a reservoir temperature of 50?C. Superheated steam at 273?C was then injectedinto the injection cell at a rate of 5.5 cc/min (cold water equivalent). The cell outletpressure was maintained at 500 psig. Produced liquid samples were collectedperiodically through a series of separators. The produced oil was divided into two halvesand several measurements and analyses were carried out on them. These includedviscosity, density, elemental analysis and liquid composition. Experimental results indicated that tetralin alone was a worthy additive andincreased recovery by 15% compared to that of pure steam. The premixed tetralincatalystrun showed improved recovery to that of pure steam by 20%. Experiments alsoshowed that, when the tetralin-catalyst solution was injected rather than mixed, theresults were equivalent to tetralin injection runs. Oil production acceleration wasdisplayed by all the runs with tetralin and tetralin-catalyst but was more pronounced withthe availability of catalyst.