Method and a system for separating and transporting gas and liquid

• US 5,009,680 A
• Filed: 06/11/1990
• Issued: 04/23/1991
• Est. Priority Date: 11/28/1988
• Status: Expired due to Fees

• Current Assignee: AKER Engineering As
• Original Assignee: AKER Engineering As
• Inventors: Brekke, Kristian
• Primary Examiner(s): Hart, Charles
• Application Number:
  US07/488,061
• Time in Patent Office: 316 Days
• Field of Search: 55/40, 55/43, 55/46, 55/55, 55/189
• US Class Current: 95/247
• CPC Class Codes: B01D 45/02 by utilising gravity
• CPC Class Codes: F17D 1/005 for a two-phase gas-liquid flow

Abstract

A method and a system are disclosed for the transportation and separation of gas from liquid and solid media in one or several stages in a manner so that the pressure in the gaseous phase from an early separator stage (1) or from another gas deposit is utilized for the transportation of the fluids produced in subsequent separator stages (2, 3, 4). Gas which is separated at high pressure in an early separator stage (1) or gas from another gas deposit is fed into a separator (3) which has effected separation at a lower pressure and the high pressure gas forces out the separated fluid which is present in the separator receiving the high pressure gas. The separator stage at which high pressure gas is received from a preceding stage or another gas source, is made up of several identical separators (2, 3, 4) which alternate in carrying out the separation phase (2), output (3) and decompression (4) so that there is at all times one separator carrying out functions within one phase.

Claims

1. A process for the transportation of gas and liquid or solid media and the separation of gas from liquid or solid media in a manner so that the pressure in the gas separated off in one separator stage is used for the transportation of separated fluids from a subsequent separator stage, comprises the steps of:

(a) separating gas off at high pressure in one separator stage or adding it from another gas source and

(b) directing said separated or added gas into a separator containing fluid from which gas has been separated at a lower pressure;

(c) said high pressure gas forcing out already separated fluid present in the separator receiving said high pressure gas.

2. A process as claimed in claim 1, wherein the lower pressure separator comprises a plurality of substantially identical separators, each of said separators operating in a work cycle and alternating in carrying out in the sequence indicated, the function phases of said process, said process being such as to ensure that one separator carries out its functions within one phase.

3. A process as claimed in claim 1 or 2, wherein

(a) phase 1 of the process is the separation of gas from liquid at a pressure necessary to maintain export of gas from the process;

(b) phase 2 is the output of liquid from the separator to an output line by gas from a preceding separator stage or from another gas deposit being fed into the separator; and

(c) phase 3 is decompressing the separator by directing gas from it to a gas output line.

4. A process as claimed in claim 1, wherein separators in the separator stage which receives said higher pressure gas are decompressed at constant mass flow of gas through a decompression valve to a gas output line after completion of the phase for transportation of oil, the separators being decompressed sequentially.

5. A system for the separation and transportation of gas and liquid, comprising first separator means (1) for separation of gas from the liquid at a first pressure, and second separator means (2, 3, 4) for separation at a lower pressure than said first pressure and for separation of further gas from the liquid to be separated out in said first separator means (1), said second separator means including at least one separator vessel (2), the upper part of said vessel (2) being connected to said separator means (1) through gas and liquid supply lines (6, resp. 7) and being further connected to a gas transportation line (9), the lower part of said vessel (2) being connected to a liquid transportation line (8).

6. A system according to claim 5, wherein said second separator means includes at least three separator vessels (2, 3, 4) connected in parallel.