Configurations and methods for gas condensate separation from high-pressure hydrocarbon mixtures

• US 8,840,707 B2
• Filed: 06/22/2005
• Issued: 09/23/2014
• Est. Priority Date: 07/06/2004
• Status: Active Grant

• Current Assignee: Fluor Technologies Corporation (Fluor Corporation)
• Original Assignee: Fluor Technologies Corporation (Fluor Corporation)
• Inventors: Mak, John
• Primary Examiner(s): Jules, Frantz
• Assistant Examiner(s): RAYMOND, KEITH MICHAEL
• Application Number:
  US11/571,591
• Publication Number:
  US 20080168797A1
• Time in Patent Office: 3,380 Days
• Field of Search: 626/32, 62618-620, 626/30, 626/31, 95159-161, 951/64, 951/65, 951/67, 951/91, 952/04, 952/06, 952/63
• US Class Current: 95/165
• CPC Class Codes: B01D 19/00 Degasification of liquids
• CPC Class Codes: B01D 3/00 Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping evaporation in general, e.g. of liquids for gas phase reactions B01B1/005; gas chromatography B01D15/08; destructive distillation C10B; preparation of alcoholic beverages by distillation C12H6/02
• CPC Class Codes: B01D 53/14 by absorption
• CPC Class Codes: C10L 3/12 Liquefied petroleum gas liquefying by pressure and cold treatment F25J

Abstract

A gas condensate production plant comprises a plurality of separation units in which C₂ and/or C₃ lighter components are stripped from the separator feeds using compressed heated stripping vapor produced from the feed in respective downstream separation units. Contemplated plants substantially reduce heating and cooling duties by using the waste heat from the compressor discharges in the separation process. Furthermore, the multi-stage fractionation according to the inventive subject matter provides improved gas condensate recovery at reduced energy costs.

Claims

1. A gas condensate production plant comprising:

a separation unit having a feed inlet that is configured to receive a two-phase mixture of (a) a hot and compressed recycle stream comprising C₂, C₃, and lighter components and (b) a hydrocarbon feed comprising C₂, C₃, and lighter components and C₄ and heavier components,

wherein the hot and compressed recycle stream comprising C₂, C₃, and lighter components is present in the two-phase mixture in an amount effective to increase a temperature of the hydrocarbon feed to allow the separation unit to operate under conditions that allow stripping of at least 50% of the C₂, C₃, and lighter components from the feed using the hot and compressed recycle stream to thereby form a separation unit vapor product comprising the at least 50% of the C₂, C₃, and lighter components, and

wherein the recycle stream has a temperature of between 200°

F. to 250°

F. and a pressure of between 1100 psig to 1400 psig, and wherein the recycle stream is generated in a second separation unit downstream of the separation unit, is in vapor form, and is compressed to a pressure at which the separation unit operates.

2. The plant of claim 1 wherein at least one of the separation unit and the second separation unit is a vapor-liquid separator.

3. The plant of claim 1 wherein the second separation unit is fluidly coupled to the separation unit such that the second separation unit receives a liquid product from the separation unit and wherein the second separation unit is further configured to produce the recycle stream.

4. The plant of claim 3 wherein the second separation unit is configured to form the recycle stream by stripping the liquid product with a compressed vapor enriched in C2 and lighter components.

5. A gas condensate production plant comprising a plurality of separation units coupled to each other such that a hot and compressed recycle stream produced from a downstream separation unit strips C₂, C₃, and lighter components from a hydrocarbon feed comprising C₂, C₃, and lighter components and C₄ and heavier components in an upstream separation unit to thereby form a liquid product comprising C₃, C₄, and heavier components, and wherein the upstream separation unit is configured to produce a vapor product comprising the C₂, C₃, and lighter components and to receive a two-phase mixture of (a) the hot and compressed recycle stream having a temperature of between 200°

F. to 250°

F. and comprising C₂, C₃, and lighter components and (b) the hydrocarbon feed wherein the hot and compressed recycle stream is present in the two-phase mixture in an amount effective to increase the temperature of the hydrocarbon feed within the two-phase mixture.

6. The plant of claim 5 wherein the liquid product formed in the upstream separation unit is fed to the downstream separation unit as a feed.

7. The plant of claim 5 wherein the upstream separation unit comprises a high-pressure vapor-liquid separator.

8. The plant of claim 5 further comprising a mixing unit configured to allow mixing of the hot and compressed recycle stream and the hydrocarbon feed prior to entry into the upstream separation unit.

9. The plant of claim 5 wherein the downstream separation unit comprises a vapor-liquid separator or a fractionator.

10. The plant of claim 5 wherein the downstream separation unit comprises a vapor-liquid separator and wherein the downstream separation unit is configured to receive a mixture of the liquid product and a compressed vapor enriched in C₂, C₃, and lighter components.

11. The plant of claim 5 wherein the downstream separation unit comprises a fractionator and wherein the downstream separation unit is configured to receive the liquid product as a feed.

12. A method of producing gas condensate comprising:

separating C₂, C₃, and lighter components from a second feed in a downstream separation unit to thereby form a liquid product comprising C₄ and heavier components;

compressing the separated C₂, C₃, and lighter components to thereby form a hot and compressed recycle stream having a temperature of between 200°

F. to 250°

F.; and

forming a two-phase mixture by combining the hot and compressed recycle stream with a first feed to strip C₂, C₃, and lighter components from the first feed in an upstream separation unit to thereby form the second feed wherein the hot and compressed recycle stream is present in the two-phase mixture in an amount effective to increase the temperature of the first feed to allow stripping of at least 50% of the C₂, C₃, and lighter components from the first feed using the hot and compressed recycle stream, and wherein the upstream separation unit produces a vapor product comprising the at least 50% of the C₂, C₃, and lighter components from the first feed.

13. The method of claim 12 wherein the step of separating the C₂, C₃, and lighter components from the second feed comprises use of a compressed vapor enriched in C₂, C₃, and lighter components as a stripping vapor in the downstream separation unit.

14. The method of claim 12 wherein the downstream separation unit comprises a vapor-liquid separator or a fractionator.

15. The method of claim 12 wherein a third separation unit provides a compressed vapor enriched in C₂, C₃, and lighter components as a stripping vapor to the downstream separation unit.

16. The method of claim 15 wherein the third separation unit produces a gas condensate sales product.