Methods and systems for optimizing carbon dioxide sequestration operations

• US 8,874,382 B2
• Filed: 04/30/2010
• Issued: 10/28/2014
• Est. Priority Date: 05/01/2009
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Verma, Sandeep, Oakes, Charles S., Ramakrishnan, Terizhandur S.
• Primary Examiner(s): Teixeira Moffat, Jonathan C
• Assistant Examiner(s): BETSCH, REGIS J
• Application Number:
  US12/771,751
• Publication Number:
  US 20100287123A1
• Time in Patent Office: 1,642 Days
• Field of Search: 62/507, 623/89, 137/7, 702/25
• US Class Current: 702/25
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: F17D 1/005 for a two-phase gas-liquid flow
• CPC Class Codes: F17D 1/04 for distribution of gas
• CPC Class Codes: F17D 3/01 for controlling, signalling, or supervising the conveyance of a product
• CPC Class Codes: G06F 30/00 Computer-aided design [CAD]
• CPC Class Codes: G06Q 99/00 Subject matter not provided for in other groups of this subclass
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 90/70 Combining sequestration of CO2 and exploitation of hydrocarbons by injecting CO2 or carbonated water in oil wells
• CPC Class Codes: Y10T 137/0396 Involving pressure control

Abstract

Methods and systems are provided for controlling operational parameters of a CO₂ compression surface facility or pipeline in order to maintain a CO₂ stream having impurities flowing in the pipeline in a liquid or supercritical phase. Sensors may be provided to sense whether the flow is single-phase or two-phase flow, and feedback provided to adjust the pressure and/or temperature at the pipeline inlet. The system is preferably optimized to limit power consumption and/or cost.

Claims

1. A method of controlling a mostly-CO2 effluent stream in a pipeline, comprising:

using at least at sensor to sense a state of said mostly-CO2 effluent stream along or at an outlet of said pipeline, and feeding an indication of said state back to a controller; and

using the controller to control at least one of operating pressure and temperature of the mostly-CO2 effluent stream in order to (i) maintain said effluent stream as a single-phase liquid or a supercritical fluid stream in the pipeline using said indication of said state of said mostly-CO2 effluent stream and (ii) cause said mostly-CO2 effluent stream to move closer to a bubble-point line, while maintaining said mostly-CO2 effluent stream as the single-phase liquid or the supercritical fluid stream, when said indication of said state of said mostly-CO2 effluent stream indicates single-phase flow.

2. A method according to claim 1, wherein:

said controlling comprises generating a phase analysis of the mostly-CO2 effluent stream, and running a simulation of the pipeline using known characteristics of the pipeline and the phase analysis in order to set operating inlet pressure and temperature criteria for said mostly-CO2 effluent stream.

3. A method according to claim 2, wherein.

said phase analysis is a pressure-temperature phase diagram computation.

4. A method according to claim 2, wherein:

said generating a phase analysis comprises obtaining a sample of said mostly-CO2 effluent stream and analyzing said sample in a laboratory.

5. A method according to claim 2, wherein:

said generating, a phase analysis comprises conducting a compositional analysis of said mostly-CO2 effluent stream utilizing at least one gas analyzer and generating said phase analysis based on aid compositional analysis.

6. A method according to claim 5, wherein:

said generating a phase analysis comprises generating a phase diagram based on said compositional analysis by utilizing equations of state.

7. A method according to claim 6, wherein

said equations of state are based on one of Helmholtz free energy, cubic equations of state, and virial equations of state.

8. A method according to claim 2, wherein:

said known characteristics of said pipeline comprise at least a diameter of said pipeline, a roughness rating for said pipeline, a length of said pipeline, and ambient conditions associated with said pipeline.

9. A method according to claim 1, wherein:

if said indication of said state of said mostly-CO2 effluent stream indicates two-phase flow, adjusting at least one of said operating press and temperature to cause said mostly-CO2 effluent stream to return o single-phase flow.

10. A method according to claim 9, wherein:

said adjusting comprises increasing said operating pressure at an inlet to said pipeline.

11. A method according to claim 9, wherein:

said adjusting comprises decreasing said operating temperature at an inlet to said pipeline.

12. A method according to claim 9, wherein:

said adjusting comprises at least one of increasing said operating pressure and decreasing said operating temperature at a location along the pipeline other than at an inlet of said pipeline.

13. A method according to claim 1, wherein:

said at least one sensor comprises at least one sensor at said pipeline outlet.

14. A method according, to claim 1, wherein:

said at least one sensor comprises a plurality of sensors at a plurality of ocations along said pipeline.

15. A method according to claim 1, wherein:

depending upon said indication of said state of said mostly-CO2 effluent stream, adjusting a compositional make-up of said mostly-CO2 effluent stream.