Enhanced Recovery of Bitumen by Steam with Chemical Additives

Abstract

ABSTRACT Enhanced recovery of bitumen by a combination of steam and caustic chemicals with and without alcohol has been investigated using both static and dynamic techniques. Static experiments were conducted on the basis of information derived from a previous investigation to define the alcoholic caustic formulations potentially effective for bitumen mobilization. The aliphatic alcohol that gave increased bitumen emulsification with a further indication of a more favorable condition for bitumen microemulsion displacement was then selected for the dynamic tests, in which a caustic concentration level up to 0.4 wt% was propagated by a saturated steam at 400 kPa through oil-bearing sand packs. Data obtained from these tests revealed a better bitumen displacement and greater sweep efficiency in steamfloods with caustic and 50% octanolic-caustic additives than in steam drive. In addition, bitumen production began earliest in the alcohol system and was accompanied by increased production rate, leading to more than 10 and 30% increases in the overall bitumen recovery compared with the nonalcoholic alkaline steam and pure steam injection processes, respectively. These results also served to reinforce the findings of the static experiments. Keywords: bitumen microemulsionbitumen recoverysteam drivesteam-caustic processsteam-caustic-octanolic process