| 摘要 |
<p>Method and apparatus for enhanced recovery of subterranean deposits. A heating fluid (32) circulates in a concentric tubing assembly (19) which attaches to a downhole heat exchanger (25). A convertible fluid (35) descends to the downhole heat exchanger (25) in the concentric tubing assembly (19) where it converts to vapor (30) by transfer of heat from the heating fluid (32). The vapor can then be used to liquefy viscous subterranean deposits (10). A feed control valve (30) controls the rate at which convertible fluid enters the downhole heat exchanger (25). Scale produced by the vaporization of the convertible fluid is purged by a purging valve (85) into the well sump.</p> |
