Assessing petroleum reservoir production and potential for increasing production rate

• US 8,145,427 B1
• Filed: 09/25/2009
• Issued: 03/27/2012
• Est. Priority Date: 09/29/2008
• Status: Active Grant

• Current Assignee: QRI Group, LLC
• Original Assignee: QRI Group, LLC
• Inventors: Saleri, Nansen G., Toronyi, Robert M.
• Primary Examiner(s): Bui, Bryan
• Application Number:
  US12/567,404
• Time in Patent Office: 914 Days
• Field of Search: 702/6, 166/252.1, 166/268, 703/9, 703/10
• US Class Current: 702/6
• CPC Class Codes: E21B 43/12 Methods or apparatus for controlling the flow of the obtained fluid to or in wells E21B43/25 takes precedence; valve arrangements E21B34/00

Abstract

Determining a production gain index (PGI) for a petroleum reservoir provides a novel leading indicator and metric that is designed to quickly assess the potential for increases in production of petroleum from an operating petroleum reservoir when implementing a recovery plan. The PGI can be determined according to the following equation:

$PGI=\frac{\mathrm{\Sigma \Delta }{q}_A}{\Sigma q_{\mathrm{Old}}}$
where, ΣΔq_A=net actual production gain of the reservoir; and ΣqOld=sum of current oil rates for existing producers. The PGI can also be determined according to the following equation:
PGI=PR×(GPI−1)
where, GPI=the global productivity index of the petroleum reservoir; and PR=the interference factor, which accounts for any losses in aggregate production gain due to well interference.

Claims

1. In a computing system having a processor and system memory and which is configured to receive and analyze data relating to net actual production gain and a sum of current oil rates for existing producers of a petroleum reservoir, a method for determining the production gain index (PGI) for a producing petroleum reservoir, comprising:

inputting into the computing system data relating to the net actual production gain of the petroleum reservoir (Σ

Δ

q_A) post project development;

inputting into the computing system data relating to the sum of current oil rates for existing producers (Σ

q_Old) of the petroleum reservoir prior to project development; and

the computing system determining, by relating the net actual production gain (Σ

Δ

q_A) of the petroleum reservoir post project development with the sum of current oil rates (Σ

q_Old) of the petroleum reservoir prior to project development, the production gain index (PGI) for the petroleum reservoir.

2. The method as in claim 1, wherein the production gain index (PGI) is determined according to the following equation:

3. The method as in claim 1, further comprising using the production gain index (PGI) as part of a method for increasing current production of petroleum from the petroleum reservoir.

4. In a computing system having a processor and system memory and which is configured to receive and analyze data relating to a global productivity index and an interference factor for a petroleum reservoir, a method for determining the production gain index (PGI) for a producing petroleum reservoir, comprising:

inputting into the computing system data relating to a global productivity index (GPI) of the petroleum reservoir;

inputting into the computing system data relating to an interference factor (PR) of the petroleum reservoir; and

the computing system determining, by relating the global productivity index (GPI) with the interference factor (PR), the production gain index (PGI) for the petroleum reservoir.

5. The method as in claim 4, wherein the production gain index (PGI) is determined according to the following equation:

PGI=PR×

(GPI−

1)

where,

GPI=the global productivity index of the petroleum reservoir; and

PR=the interference factor, which accounts for any loss in aggregate production gain due to well interference.

6. The method as in claim 4, wherein inputting into the computing system data relating to the global productivity index (GPI) of the petroleum reservoir further comprises:

inputting into the computing system data relating to a sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New);

inputting into the computing system data relating to a sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old); and

the computing system determining, by relating the sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New) with the sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old), the global productivity index (GPI) of the petroleum reservoir.

7. The method as in claim 6, wherein the global productivity index (GPI) of the petroleum reservoir is determined according to the following equation:

8. The method as in claim 4, wherein inputting into the computing system data relating to the interference factor (PR) of the petroleum reservoir further comprises:

inputting into the computing system data relating to a sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New);

inputting into the computing system data relating to a sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old);

inputting into the computing system data relating to distances (d) between adjacent producers; and

the computing system determining, by relating together the sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New), the sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old), and the distances (d) between adjacent producers, the interference factor (PR) of the petroleum reservoir.

9. The method as in claim 8, wherein the interference factor (PR) of the petroleum reservoir is determined according to the following equation:

PR=Σ

J_New/Σ

J_Old

where,

Σ

J_New=sum of productivity indices of all producers post project development, stbpd/psi (standard barrels produced per day divided by pressure in pounds per square inch) and is based in part on data relating to the distances (d) between adjacent producers; and

Σ

J_Old=sum of productivity indices of all producers prior to project development, stbpd/psi.

10. The method as in claim 4, wherein the global productivity index (GPI) and interference factor (PR) are determined based on productivity indices of producing wells, wherein the productivity index (J) of each producing well is determined by:

inputting in the computing system data relating to a stabilized flow rate of the producing well at surface conditions;

inputting in the computing system data relating to a drawdown of the producing well; and

the computer system determining the productivity index of the producing well by dividing the stabilized flow rate of the producing well at surface conditions by the drawdown of the producing well.

11. The method as in claim 10, wherein the drawdown of the producing well is determined by placing a pressure gauge in the producing well, measuring flowing bottom-hole pressure (p_w) after the well has flowed at a stabilized rate, measuring a static pressure (p_e) after a shut-in period, and determining the difference in static bottom-hole pressure and stabilized flowing bottom-hole pressure (p_e−

p_w) for the well.

12. The method as in claim 10, wherein the stabilized flow rate of the producing well is measured at the surface by tank gauging or with a metered test separator.

13. The method as in claim 4, further comprising using the production gain index (PGI) as part of a method for increasing current production of petroleum from the petroleum reservoir.

14. In a computing system having a processor and system memory and which is configured to receive and analyze data relating to a global productivity index and an interference factor for a petroleum reservoir, a method for determining the production gain index (PGI) for a producing petroleum reservoir, comprising:

inputting into the computing system data relating to a sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New);

inputting into the computing system data relating to a sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old);

inputting into the computing system data relating to distances (d) between adjacent producers;

the computing system determining, by relating the sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New) with the sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old), a global productivity index (GPI) of the petroleum reservoir;

the computing system determining, by relating together the sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New), the sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old), and the distances (d) between adjacent producers, the interference factor (PR) of the petroleum reservoir; and

the computing system determining, by relating the global productivity index (GPI) with the interference factor (PR), the production gain index (PGI) for the petroleum reservoir.

15. The method as in claim 14, wherein the computing system determines the production gain index (PGI) according to the following equation:

PGI=PR×

(GPI−

1).

16. A computer program product comprising one or more physical storage media having stored thereon executable instructions which, when implemented by a computing system, will cause the computing system to carry out the method of claim 14.

17. A method for determining the production gain index (PGI) for a producing petroleum reservoir, comprising:

determining a sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New);

determining a sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old);

determining distances (d) between adjacent producers;

determining, by relating the sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New) with the sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old), a global productivity index (GPI) of the petroleum reservoir;

determining, by relating together the sum of productivity indices of all producers of the petroleum reservoir post project development (Σ

J_New), the sum of productivity indices of all producers of the petroleum reservoir prior to project development (Σ

J_Old), and the distances (d) between adjacent producers, the interference factor (PR) of the petroleum reservoir; and

determining, by relating the global productivity index (GPI) with the interference factor (PR), the production gain index (PGI) for the petroleum reservoir.

18. The method as in claim 17, wherein the global productivity index (GPI) is determined according to the following equation:

19. The method as in claim 17, wherein the productivity index (J) of each producing well is determined by:

measuring a stabilized flow rate of the producing well at surface conditions;

measuring a drawdown of the producing well; and

dividing the stabilized flow rate of the producer at surface conditions by the drawdown of the producer.

20. The method as in claim 19, wherein the drawdown of the producing well is determined by placing a pressure gauge in the producing well, measuring flowing bottom-hole pressure (p_w) after the well has flowed at a stabilized rate, measuring a static pressure (p_e) after a shut-in period, and determining the difference in static bottom-hole pressure and stabilized flowing bottom-hole pressure (p_e−

p_w) for the well.

21. The method as in claim 19, wherein the stabilized flow rate of the producing well is measured at the surface by tank gauging or with a metered test separator.

22. The method as in claim 17, further comprising using the production gain index (PGI) as part of a method for increasing current production of petroleum from the petroleum reservoir.