3-D Physical Model Studies of Downhole Catalytic Upgrading of Wolf Lake Heavy Oil Using THAI

摘要

THAI - 'Toe-to Heel Air Injection' is an integratedrnhorizontal wells- in situ process for the recovery andrnupgrading of heavy crude oil. In addition to thermalrnupgrading, further upgrading can be achieved byrnemplacing a catalyst layer around the horizontalrnproducer well, in effect creating a downhole reactor. Arnseries of six catalytic tests was performed in two 3Drncombustion cells to investigate the degree of upgradingrnachievable with 10.5 API gravity Wolf Lake oil. Thernmain factors investigated were: the type of HDS catalystrn(NiMo, CoMo), extrudate or crushed catalyst, andrncatalyst loading. Normally, the well configuration wasrnHIHP, I.e. a horizontal injector and a single horizontalrnproducer well in line drive, but one test used a dualrnproducer, HI2HP. The results of these tests show that thernbasic process is very stable over a 10 hour period,rnmaintaining average peak combustion temperatures ofrn500 to 600C. Thermal upgrading alone (THAI) achievedrna nearly 10 point increase in the API gravity of thernproduced oil. This was increased by a further 4 to 7 APIrnpoints using the catalytic process (CAPRI). This indicatesrnthat it may be possible to convert a heavy crude oil tornalmost a light oil product in a one-step in situ reservoirrnprocess. The oil recoveries were consistently very high,rnat around 85 %OOIP, with the produced oil having arnviscosity as low as 10 mPas at 20 oC. The processrndemonstrated robust stability when changes in airrninjection rate were made and there was also an oilrnproductivity gain when operating at low water air ratios,rnWAR< 1.0.