Subsea well production flow system

• US 20050061515A1
• Filed: 09/14/2004
• Published: 03/24/2005
• Est. Priority Date: 09/24/2003
• Status: Active Grant

• Current Assignee: OneSubsea IP UK Limited (SLB)
• Original Assignee: Cooper Cameron Corporation (SLB)
• Inventors: Hopper, Hans Paul
• Granted Patent: US 7,363,982 B2
• Time in Patent Office: Days
• US Class Current: 166/367
• CPC Class Codes: B01D 17/00 Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion devices for separating or removing fatty or oily substances or similar floating material from water, waste water, or sewage C02F1/40; cleaning or keeping clear the surface of open water from oil or like materials E02B15/04; arrangements for separating lubricants from refrigerants F25B43/02
• CPC Class Codes: B01D 17/0217 by centrifugal force
• CPC Class Codes: B01D 17/12 Auxiliary equipment particularly adapted for use with liquid-separating apparatus, e.g. control circuits
• CPC Class Codes: B01D 19/0042 modifying the liquid flow B01D19/0021 takes precedence
• CPC Class Codes: B01D 19/0057 the centrifugal movement being caused by a vortex, e.g. using a cyclone, or by a tangential inlet
• CPC Class Codes: B01D 21/265 by using a vortex inducer or vortex guide, e.g. coil B01D21/0054 takes precedence
• CPC Class Codes: B01D 2221/04 Separation devices for treating liquids from earth drilling, mining
• CPC Class Codes: B01D 53/00 Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols, recovery of volatile solvents by condensation B01D5/00; sublimation B01D7/00; cold traps, cold baffles B01D8/00; working-up undefined gaseous mixtures obtained by cracking hydrocarbon oils C10G70/00; cleaning coal gas C10K; working-up of natural gas, or synthetic natural gas, C10L3/10; separation of difficult-to-condense gases or air by liquefaction F25J; for investigating materials G01N30/00
• CPC Class Codes: E21B 33/038 Connectors used on well heads, e.g. for connecting blow-out preventer and riser
• CPC Class Codes: E21B 34/04 in underwater well heads
• CPC Class Codes: E21B 43/36 Underwater separating arrangements E21B43/38 takes precedence

Abstract

Methods and apparatus for flowing a subsea well. The method comprises the steps of: supplying a multi-phase medium from a subsea tree 18 to a removable separator package 10; separating the multi-phase flow into one or more phases at the desired pressures, the pressures being controlled by one or more pressure control devices 51, 67, 71, 75, 76, 77, 78, 79 on one or more outlets from the separator package 10; and analysing each of the one or more phases to determine the amount and quality of products produced by the well.

Claims

1. A method of flowing a subsea well, the method comprising the steps of:

supplying a multi-phase medium from a subsea tree to a removable separator package;

separating the multi-phase flow into one or more phases at the desired pressures, the pressure being controlled by one or more pressure control devices on one or more outlets from the separator package; and

analysing each of the one or more phases to determine the amount and quality of products produced by the well.

2. A method according to claim 1, wherein the analysis is carried out subsea.

3. A method according to claim 1, wherein the analysis is carried out at the surface.

4. A method according to claim 1, wherein the pressure of one or more of the constituent phases is reduced to surface or atmospheric pressure.

5. A method according to claim 4, wherein the pressure to which one or more phases is/are reduced to is below the hydrostatic pressure in the bore at the seabed.

6. A method according to claim 1, further comprising the step of pumping one or more of the constituent phases to the analysis location.

7. A method according to claim 1, wherein the separation of the multi-phase flow is carried out by a toroidal separator.

8. A system for use in flowing a sea well, the system comprising:

a subsea tree for, in use, connection to a wellhead;

a separator package in fluid communication with a fluid take off from the subsea tree, such that, in use, a multi-phase medium can flow through the subsea tree into the separator package for separation into one or more phases;

a pressure control device on each of one or more outlets from the separator package for allowing the system to be operated at different wellhead pressures.

9. A system according to claim 8, wherein the separator package includes a toroidal separator.

10. A system according to claim 8, wherein the separator package is substantially vertically aligned with the subsea tree.

11. A system according to claim 8, wherein the separator package is placed adjacent to the subsea tree.

12. A system according to claim 8, further comprising a pressure containing device for containing the pressure of the fluid from within the tree, whilst permitting wire line, cable or coil tubing access through the tree.

13. A system according to any claim 8, wherein the pressure control device is either a choke or a pump.

14. A system according to claim 8, further comprising valves and a ram isolation package to facilitate a reduction in the pressure in the well bore when required.

15. A system according to claim 8, further comprising an emergency disconnect package.

16. A system according to claim 8, wherein the outlets from the separator package are connected to flow lines in pre-existing subsea infrastructure.

17. A system according to claim 8, wherein the outlets from the separator package are connected to individual flow lines to the surface.