Monitoring of downhole parameters and tools utilizing fiber optics

• US 6,268,911 B1
• Filed: 05/01/1998
• Issued: 07/31/2001
• Est. Priority Date: 05/02/1997
• Status: Expired due to Fees

• Current Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Original Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Inventors: Johnson, Michael, Harrell, John, Tubel, Paulo, Voll, Benn, Bidigare, Brian
• Primary Examiner(s): Evans, F. L.
• Application Number:
  US09/070,953
• Time in Patent Office: 1,187 Days
• Field of Search: 367/81, 252/53, 252/56, 356/326, 356/301
• US Class Current: 356/72
• CPC Class Codes: E21B 33/1275 inflated by down-hole pumping means operated by a down-hole drive
• CPC Class Codes: E21B 37/06 using chemical means for preventing or limiting , e.g. eliminating, the deposition of paraffins or like substances
• CPC Class Codes: E21B 41/0035 Apparatus or methods for multilateral well technology, e.g. for the completion of or workover on wells with one or more lateral branches
• CPC Class Codes: E21B 41/02 in situ inhibition of corrosion in boreholes or wells
• 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
• CPC Class Codes: E21B 43/16 Enhanced recovery methods for obtaining hydrocarbons
• CPC Class Codes: E21B 43/20 Displacing by water
• CPC Class Codes: E21B 43/25 Methods for stimulating production by vibrating earth formations E21B43/003
• CPC Class Codes: E21B 43/26 by forming crevices or fractures
• CPC Class Codes: E21B 47/00 Survey of boreholes or wells monitoring pressure or flow of drilling fluid E21B21/08
• CPC Class Codes: E21B 47/017 Protecting measuring instruments
• CPC Class Codes: E21B 47/06 Measuring temperature or pressure
• CPC Class Codes: E21B 47/07 Temperature
• CPC Class Codes: E21B 47/107 using acoustic means
• CPC Class Codes: E21B 47/11 using tracers; using radioactivity
• CPC Class Codes: E21B 47/113 using electrical indications; using light radiations
• CPC Class Codes: E21B 47/135 using light waves, e.g. infrared or ultraviolet waves
• CPC Class Codes: E21B 49/00 Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
• CPC Class Codes: E21B 49/006 Measuring wall stresses in the borehole
• CPC Class Codes: E21B 49/008 by injection test; by analysing pressure variations in an injection or production test, e.g. for estimating the skin factor measuring pressure E21B47/06
• CPC Class Codes: E21B 49/08 : Obtaining fluid samples or testing fluids, in boreholes or wells
• CPC Class Codes: G01D 5/268 : using optical fibres G01D5/28 - G01D5/38 take precedence
• CPC Class Codes: G01N 21/31 : Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry G01N21/72 takes precedence
• CPC Class Codes: G01V 1/40 : specially adapted for well-logging
• CPC Class Codes: G01V 1/42 : using generators in one well and receivers elsewhere or vice versa G01V1/52 takes precedence
• CPC Class Codes: G01V 1/46 : Data acquisition
• CPC Class Codes: G01V 1/52 : Structural details
• CPC Class Codes: G01V 11/00 : Prospecting or detecting by methods combining techniques covered by two or more of main groups G01V1/00 - G01V9/00
• CPC Class Codes: G01V 11/002 : Details, e.g. power supply systems for logging instruments, transmitting or recording data, specially adapted for well logging, also if the prospecting method is irrelevant means for transmitting well survey signals E21B47/12; signal transmission systems in general G08C; transmission in general H04B
• CPC Class Codes: G01V 2210/6163 : Electromagnetic
• CPC Class Codes: G01V 2210/6167 : Nuclear
• CPC Class Codes: G01V 7/08 : using balances
• CPC Class Codes: G01V 7/16 : specially adapted for use on moving platforms, e.g. ship, aircraft
• CPC Class Codes: G01V 8/02 : Prospecting

Abstract

The present invention provides systems utilizing fiber optics for monitoring downhole parameters and the operation and conditions of downhole tools. In one system fiber optics sensors are placed in the wellbore to make distributed measurements for determining the fluid parameters including temperature, pressure, fluid flow, fluid constituents and chemical properties. Optical spectrometric sensors are employed for monitoring chemical properties in the wellbore and at the surface for chemical injection systems. Fiber optic sensors are utilized to determine formation properties including resistivity and acoustic properties compensated for temperature effects. Fiber optic sensors are used to monitor the operation and condition of downhole devices including electrical submersible pumps and flow control devices. In one embodiment, a common fluid line is used to monitor downhole parameters and to operate hydraulically-operated devices. Fiber optic sensors are also deployed to monitor the physical condition of power lines supplying high electric power to downhole equipment. A light cell disposed downhole is used to generate electric power in the wellbore, which is used to charge batteries.

Claims

1. A system for monitoring a downhole parameter of interest within a production wellbore, comprising:

(a) an optical spectrometer installed in the production wellbore, said optical spectrometer making measurements of the downhole parameter in response to the supply of optical energy to the spectrometer;

(b) a source of optical energy providing the optical energy to the optical spectrometer and

(c) a sol gel optical probe in the wellbore for providing an indication the spectrometer of chemical composition of the produced fluid.

2. The system of claim 1 wherein the spectrometer provides signals responsive to a downhole parameter which is one of (i) presence of gas in a fluid, (ii) presence of water in a fluid, (iii) amount of solids in fluid, (iv) density of a fluid, (v) constituents of a downhole fluid, and (vi) chemical composition of a fluid.

3. The system of claim 1 wherein the source of optical energy is located in the wellbore.

4. The system of claim 1 further comprising a processor determining the downhole parameter utilizing the measurements from the optical spectrometer.

5. The system of claim 4 wherein the processor processes data at least in part downhole.

6. The system of claim 1 further comprising an optical probe installed in the wellbore for providing an indication to the spectrometer of at least one of (i) presence of gas in a fluid, (ii) presence of water in a fluid, (iii) amount of solids in fluid, (iv) density of a fluid, and (v) constituents of a downhole fluid.

7. A system for monitoring a downhole parameter of interest of a producing wellbore in a subterranean formation comprising:

(a) at least one fiber optic sensor installed in the wellbore for providing an indication of the parameter of interest;

(b) an optical spectrometer responsive to the indication of the parameter of interest from said at least one fiber optic sensor; and

(c) a source of optical energy providing optical energy to the at least one fiber optic sensor to enable said fiber optic sensor to provide the indication of the parameter of interest.

8. The system of claim 7 wherein the parameter of interest is selected from the group consisting of (i) a property of fluid produced from the formation, (ii) a property of the formation, and, (iii) a property of the wellbore.

9. The system of claim 7 wherein said spectrometer is located at a position selected from (i) surface of the earth, and, (ii) within the wellbore.

10. The system of claim 9 wherein the parameter of interest is a chemical property of the formation fluid, and wherein the at least one fiber optic sensor comprises a sol gel indicator.

11. The system of claim 7 further comprising an additional fiber optic sensor for measuring a physical property of the formation fluid.

12. The system of claim 7 further comprising an additional fiber optic sensor for making a measurement wherein the selected from the group consisting of (i) temperature, and, (ii) pressure.

13. The system of claim 7 further comprising an additional fiber optic sensor for making a measurement of stress of the formation, and wherein the at least one additional fiber optic sensor is responsive to a state of strain of a casing in the borehole.

14. The system of claim 7 wherein the borehole is a cased borehole.