Crude Oil Absorption (Patent No: 613199)

Inventor: Clark, Lincoln

Location: Calgary

Comments: N/A

Description: THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A process for the enrichment of crude oil with higher hydrocarbons and the simultaneous depletion of the crude oil in lighter hydrocarbons with a consequent reducement of its vapor pressure which comprises contacting, at a superatmospheric pressure not greater than about 1000 pounds per square inch absolute, crude oil with separator gas normally associated with oil production, separating the enriched crude and flash, the separated crude at two successively reduced pressures, the gases obtained from the first flash being recycled to the absorption zone and those obtained from the second flash being recycled to the first flash zone, and contacting the crude in said first flash zone with said recycled gases, all operations being carried out substantially without supplying heat to any step in the process.

2. A process as defined in claim 1 wherein said absorption is operated at a pressure of between 200 and 300 pounds per square inch absolute, said first flash being carried out at a pressure of between 40 and 50 pounds per square inch absolute and said second flash being operated at a pressure of between 7 and 15 pounds per square inch absolute.

3. A process as defined in claim 2 wherein said absorption is operated at about 215 pounds per square inch absolute and said first and second flashes at about 40 and 7.5 pounds per square inch absolute respectively.

4. A process as defined in claim 1, 2 or 3 wherein the separator gas is freed from any water and liquid hydrocarbons present in a scrubbing zone before being passed to the absorption zone.

5. A process as defined in claim 1, 2 or 3 wherein the crude oil is of high methane ethane content and is subjected to a preliminary flash under partial vacuum be~being passed to the absorption zone.

6. An apparatus for the enrichment of crude oil with higher hydrocarbons and the simultaneous depletion of the crude oil in lighter hydrocarbons with a consequent reduction of its vapor pressure, said apparatus being devoid of heating coils or heat exchangers, comprising an absorber containing means for intimately contacting liquid and a gas, means for introducing a liquid into the upper part of said absorber and means for introducing a gas into the lower part of said absorber, a first flash chamber, means for the introduction of liquid from the bottom of said absorber into said first flash chamber, means for maintaining said first flash chamber at a lower pressure than said absorber, means for recycling gases from said first flash chamber to said absorber, a second flash chamber, means for introducing liquid from said first flash chamber to said second flash chamber, means for maintaining said second flash chamber at a lower pressure than said first flash chamber, means for recycling gases from said second flash chamber to said first flash chamber and means for withdrawing liquid from said second flash chamber.

7. An apparatus as defined in claim 6 wherein the means for supplying gas to said absorber includes a scrubber tower for freeing said gas of undesired liquids.

8. An apparatus as defined in claim 6 wherein the means for supplying liquid to said absorber includes a preliminary flash tower for reducing the content by violatiles in said liquid.

9. An apparatus as defined in claim 6, 7 or 8 wherein the means for recycling gas from said second flash chamber to said first flash chamber includes a scrubber.