SOLVENT ASSISTED STARTUP TECHNIQUES FOR IN SITU BITUMEN RECOVERY WITH SAGD WELL PAIRS, INFILL WELLS OR STEP-OUT WELLS

摘要

An in situ bitumen recovery startup process can include injecting a solvent containing startup fluid into a first horizontal well, providing a pressure sink in a second horizontal well for pressure drive of the solvent toward the second well to mobilize the interwell region, and establishing fluid communication between the first horizontal well and the second horizontal well. Other startup processes can include selecting startup intervals along the wells and, for each interval, isolating the interval and injecting solvent at the interval location to enhance mobility. The processes may be applied to SAGD well pairs as well as infill wells, step-out wells and/or multilateral wells.