| 摘要 |
<p>Extraction process comprising the following steps: (i) contacting a feed (e.g. a heavy hydrocarbon oil) with an extractant (e.g. propane and/or butane) in an extraction zone, (ii) removing a product (e.g. asphalt) from a lower part of the extraction zone, (iii) heating at least part of a fluid removed from an upper part of the extraction zone, (iv) separating heated fluid in a separation zone into fluids of different density, and (v) introducing at least part of a fluid of higher density into the upper part of the extraction zone. The invention further relates to an extraction apparatus comprising a housing (1) having feed- and extractant-inlet means (2, 19), first product outlet means (5) in its lower end part (e.g. comprising a settling section and mixing means for feed and extractant) and in its upper end part fluid outlet means (7) communicating via heat exchange means with a settling vessel (11) having in its upper section second product outlet means (13) and in its lower section reflux outlet means (15) communicating with the upper end part of the housing.</p> |
