| 摘要 |
<p>A METHOD OF RECOVERING VISCOUS PETROLEUM FROM A SUBTERRANEAN, PETROLEUM-CONTAINING FORMATION A method is described for recovering viscous petroleum from subterranean petroleum-containing formations penetrated by at least one injection well and by at least one production well, both wells being in fluid communication with the petroleum-containing formation. The method comprises the steps of drilling and completing at least to the top of the petroleum-containing formation at least one intermediate well between the injection and production wells and in fluid communication with the petroleum-containing formation. While the intermediate well is closed in, a hydrocarbon solvent having a specific gravity less than that of the formation petroleum is injected via the injection well into the lower part of the formation and, after the solvent is in place at the bottom of the petroleum-containing formation, pressure is applied to the injection and/or production wells and the intermediate well is opened thus enhancing the flow of the solvent from the bottom of the formation to the top. Petroleum and solvent is then produced from the or each production well.</p> |
