GB2246866A - Borehole water content logging system and method - Google Patents
Borehole water content logging system and method Download PDFInfo
- Publication number
- GB2246866A GB2246866A GB9114000A GB9114000A GB2246866A GB 2246866 A GB2246866 A GB 2246866A GB 9114000 A GB9114000 A GB 9114000A GB 9114000 A GB9114000 A GB 9114000A GB 2246866 A GB2246866 A GB 2246866A
- Authority
- GB
- United Kingdom
- Prior art keywords
- fluid
- borehole
- impedance
- water
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 44
- 238000000034 method Methods 0.000 title claims description 9
- 239000012530 fluid Substances 0.000 claims abstract description 33
- 238000005070 sampling Methods 0.000 claims abstract description 9
- 239000012223 aqueous fraction Substances 0.000 claims description 12
- 239000004020 conductor Substances 0.000 claims 2
- 230000005540 biological transmission Effects 0.000 claims 1
- 239000000203 mixture Substances 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 238000001739 density measurement Methods 0.000 description 1
- 230000005251 gamma ray Effects 0.000 description 1
- 238000002847 impedance measurement Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—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
- E21B49/08—Obtaining fluid samples or testing fluids, in boreholes or wells
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/22—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance
- G01N27/223—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance for determining moisture content, e.g. humidity
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/10—Locating fluid leaks, intrusions or movements
- E21B47/113—Locating fluid leaks, intrusions or movements using electrical indications; using light radiations
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Geology (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Environmental & Geological Engineering (AREA)
- Geochemistry & Mineralogy (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- General Physics & Mathematics (AREA)
- Pathology (AREA)
- Geophysics (AREA)
- Health & Medical Sciences (AREA)
- Immunology (AREA)
- Analytical Chemistry (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Health & Medical Sciences (AREA)
- Biochemistry (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
A logging sonde 17 has a sampling cell 22 to sample fluid flowing in the borehole. The cell has spaced electrodes 40, 47 to sense the impedance of the fluid flowing between the electrodes. The impedance signal is passed to the surface where electronics apparatus 35 determines the fractional water content of the fluid in accordance with the impedance signal and in accordance with one or other stated equations depending on whether the fluid has a water continuous or an oil continuous phase. <IMAGE>
Description
BOREHOLE WATER CONTENT LOGGING SYSTEM AND METHOD
The present invention relates to well logging systems and methods, and particularly to well logging systems and methods for measuring the water content of a fluid containing oil and water in the borehole.
The present invention is a water fraction well logging system and method which logs a fluid in a borehole traversing an earth formation. A well logging sonde includes a sample cell which samples the fluid flowing in the borehole and a device which cooperates with the sample cell that determines the impedance of the sample fluid. A network connected to the device provides an impedance signal corresponding to the impedance of the sample fluid. A well logging cable connected to the circuit carries the impedance signal from the circuit to the surface. Surface electronics include circuitry for deriving the information about the water content of the fluid in accordance with the impedance signal.
The objects and advantages of the invention will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings wherein one embodiment of the invention is illustrated by way of example. It is to be expressly understood, however, that the drawings are for illustration purposes only and are not to be construed as defining the limits of the invention.
Figure 1 is a graphical representation of a well logging system constructed in accordance with the present invention.
Figure 2 is a drawing of the outer electrode used in the well logging system shown in Figure 1.
Figure 3 is a cutaway diagram showing the inner electrode and outer electrode of the well logging system shown in Figure 1.
Figure 4 is a simplified block diagram of the well logging system shown in Figure 1.
One of the primary applications of production logging is to determine the oil and water flow rates at various depths in a producing well. A continuous spinner flow meter can measure the total flow rate, but to determine the individual rates of the oil and water, a measurement of the percent water content or water fraction is also required.
Currently the most accepted means of determining water content uses a density measurement which is obtained from either a pressure differential or a gamma ray attenuation tool.
In a well producing gas and liquid, the water content calculation is very accurate since there is a large density difference between the gas and liquid. However, in an oil/water well the accuracy of the water content calculation suffers due to the smaller density contrast between oil and water.
The present invention offers a new and improved method of determining water content in an oil/water producing (.11 which is based upon the measured electrical impedance of a fluid mixture in a sampling chamber.
From the measured impedance and the known dimensions of the cell, two properties of the fluid mixture, the resistivity and the dielectric constant, can be determined.
The impedance, Z, is a complex quantity which can be expressed as:
(1) Z = R - j f (62 C) where R = the resistance (ohms) between the. electrodes, 62 = 2r times the frequency (hertz), C = the capacitance (farads) between the electrodes and
j = the imaginary operator ( < R and C will change as the fluid composition changes between the electrodes. The cell geometry, the electrode spacing and length, will also influence the measured R and C but this influence will remain constant for a particular cell.The more basic quantities or properties of the fluid, the resistivity and the dielectric constant k, can be obtained from the measured values of R and C through the following equations:
(2) p = R/g1 and
(3) k = Cig2 where g1 and g2 are constants for a fix cell geometry.The cell constants for a coaxial cylindrical configuration can be theoretical derived and expressed by the following equations:
(4) g1 = (6.266*log(d1/d2)/d3) m-1
(5) g2 = t1.413*d3/log(d1/d2)]*10~12F Q are referring to Fig. 3, dl = inner diameter of electrode 40 (inches), d2.= outer diameter of electrode 47 (inches) and d3 = length of electrode 47 (inches) Thus from the measured Z and the known dimensions of the cell, the two properties of the fluid mixture, and k, can be determined.
An oil and water mixture exists in either a water continuous phase, oil in water, or in an oil continuous phase, water in oil. In a water continuous phase, the resistance R is the dominating term of the impedance~measurement and in-the oil continuous phase the imaginary term (1/Co C) is dominating. In both cases, the remaining term is so small that it can be neglected. The only exception would bye an application where the water is significantly fresher than formation or produced water.
For the water continuous case, the resistance R or the resistivity is used to determine the water content. The resistivity of the oil is infinite and the resistivity of the water is a known function of salinity and temperature. The mixing relationship between the measured resistivity and the water fractions given .by the equation:
(6) Y = (W/ p )m where Y = water fraction, p = measured resistivity,p w = water resistivity and m = a constant exponent of approximately (2/3).
Equation (6) is a modified form of the general Hanai-Bruggeman
Equation which is well known in the field. Application of equation (6) requires knowledge of the water resistivity which can be obtained in production logging by measuring the impedance of the 100% water in the bottom of the borehole or by shutting in the well so the water and oil can separate.
( For the oil continuous. case, the imaginary term,
1/ ) c, of the impedance measurement is used to determine the
water. fraction. Since the frequency of the electronics will be
known, the capacitance C and the dielectric constant k can be
calculated from the imaginary term. The dielectric constant of
oil is approximately 2.3 and the dielectric constant of water
is 80 at room temperature. The dielectric constant of water is
a known function of temperature and can be considered constant
over a typical logging interval.The relationship between the
measured dielectric constant and the water fraction can be
obtained from the following equation:
(7) l-Y = t(k - kw)/(ko - kW)](ko/k)n where Y = water fraction = the measured dielectric constant, k0 = the dielectric constant of oil, kw = the dielectric
constant of water, and n = a constant exponent of approximately
(1/3).
Equation (7) is. also a modification of Hanai's and Bruggeman's more general equation.
With reference to Figure 1 there is shown a borehole
5 traversing an earth formation 8. Borehole 5 has liquid 12
flowing in it in..an upward direction. Production.iogging tool
17 is inserted into fluid 12 in borehole 5 and may be
stationary or moving. Only a portion of logging tool 17 is
dedicated to the present invention and that includes a test
cell 22 with an electronic section 26. Electrical information
developed in logging tool 17 is sent to the surface by way of a
well logging cable 30 to surface. electronics. 35. A wheel 36
provides a signal, represented by a dashed line 38, to surface
electronics .35 corresponding to . the depth of tool 17 in
borehole 5.
Referring now to Figure 2, test cell 22 has an outer electrode 40 having slots or openings 43.' Electrode 40 provides part of the outer shell for well logging tool 17.
In Figure 3 another electrode or inner electrode 47 is shown which is affixed to outer electrode 40 by insulator support member 53. Electrical wires 57 and. 58 electrically connect outer electrode 40 and inner electrode 47 to electronic section 26 as hereinafter explained.
With reference to Figure 4, electrodes 40, 47 are connected by wires 57 and 58, respectively, to a pick-off circuit 65. In essence, pick-off circuit 65 provides a signal corresponding to the impedance of the fluid between electrodes 40 and 47. Thus electrodes 40, 47 and fluid 12 form a capacitor whose impedance is related to the dielectric constant and resistivity of fluid as hereinbefore explained. The signal provided by pick-off circuit 65 corresponds to the impedance having a real or resistive portion and an imaginary or reactive portion as shown in equation 1. The signal from pick-off circuit 65 is converted : to digital signals by an analog-to-digital converter 67 and provided to microprocessor means 70. Microprocessor means prepares the digital signals so that they may be transmitted wuphole by cable means 30. The signal from cable means 30 is provided to computer means 75. The computer means determines the water fraction Y and may supply signals representing the water fraction to a tape and to a recorder.
Claims (9)
1. A borehole logging system for measuring the water content of a fluid containing oil and water in the borehole, said system comprising:
a logging sonde connected by a cable to surface electronics apparatus;
said sonde comprises a sampling cell for sampling fluid flowing in the borehole and including impedance means for sensing the impedance of the sampled fluid, and signal means for providing a signal representative of the sensed impedance and passing the signal to said cable for transmission to said surface electronics apparatus; and
said surface electronics apparatus includes means for providing a signal representative of the fractional water content of the borehole fluid in accordance with said sensed impedance signal.
2. A system according to claim 1 wherein said sampling cell includes a shell of electrically conductive material and having openings permitting the borehole fluid to flow into and out of the shell.
3. A system according to claim 2 wherein said sampling cell further includes a member of electrically conductive material disposed within and spaced apart from said shell, said shell and said member forming a pair of electrodes to serve as said impedance means.
4. A system according to claim 3 wherein said signal means is adapted to provide a signal representative of the impedance of borehole fluid flowing in use between said electrodes.
5. A system according to any one of claims 1 to 4 wherein said surface electronics apparatus includes means for utilizing the impedance signal and the following equation:
Y = (p /p )m to provide said signal representative of the water fraction in the case where the fluid has a water continuous phase, wherein:
Y is the water fraction,
p is the fluid resistivity derived from the impedance signal, is the resistivity of the water, and
m is a constant exponent of approximately 2/3.
6. A system according to any one of claims 1 to 5 wherein said surface electronics apparatus includes means for utilizing the impedance signal and the following equation:
l-Y = ((k - kW)/(ko - kw)](ko/k) to provide said signal representative of the water fraction in the case where the fluid has an oil continuous phase, wherein:
Y is the water fraction,
k is the fluid dielectric constant derived from the impedance signal, k0 is the dielectric constant of the oil, kw is the dielectric constant of the water, and
n is a constant exponent of approximately 1/3.
7. A method of logging a borehole to measure the water content of a fluid containing oil and water in the borehole, said method comprising:
sampling the fluid flowing in the borehole by means of a sampling cell in a logging sonde suspended by a cable in the borehole;
sensing the impedance of the sampled fluid in the sampling cell;
providing a signal representative of the sensed impedance and passing the signal by the cable to the surface; and
providing, at the surface, a signal representative of the fractional water content of the borehole fluid in accordance with said sensed impedance signal.
8. A borehole logging system substantially as described herein with reference to the accompanying drawings.
9. A method according to claim 7 and substantially as claimed herein with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US56302090A | 1990-08-06 | 1990-08-06 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9114000D0 GB9114000D0 (en) | 1991-08-14 |
| GB2246866A true GB2246866A (en) | 1992-02-12 |
Family
ID=24248765
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9114000A Withdrawn GB2246866A (en) | 1990-08-06 | 1991-06-28 | Borehole water content logging system and method |
Country Status (3)
| Country | Link |
|---|---|
| BR (1) | BR9103383A (en) |
| GB (1) | GB2246866A (en) |
| NO (1) | NO912802L (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5453693A (en) * | 1993-10-01 | 1995-09-26 | Halliburton Company | Logging system for measuring dielectric properties of fluids in a cased well using multiple mini-wave guides |
| GB2313196A (en) * | 1996-05-15 | 1997-11-19 | Western Atlas Int Inc | Downhole multiphase flow sensor |
| GB2471108A (en) * | 2009-06-17 | 2010-12-22 | Vetco Gray Controls Ltd | Monitoring of undesirable fluid ingress into subsea control modules |
| EP2574722A1 (en) * | 2011-09-28 | 2013-04-03 | Welltec A/S | A downhole sampling tool |
| GB2495132A (en) * | 2011-09-30 | 2013-04-03 | Zenith Oilfield Technology Ltd | Fluid mixture determination |
| WO2015055767A1 (en) | 2013-10-16 | 2015-04-23 | Roxar Flow Measurement As | Scale monitoring and inhibitor quantification technique in multiphase meters |
| US9541436B2 (en) | 2011-11-22 | 2017-01-10 | Lufkin Industries, Llc | Distributed two dimensional fluid sensor |
| CN108442920A (en) * | 2018-02-08 | 2018-08-24 | 天津大学 | The water phase conductivity measuring apparatus of aqueous phase multiphase flow in upward vertical tube |
| US10107789B2 (en) | 2013-03-11 | 2018-10-23 | Zenith Oilfield Technology Limited | Multi-component fluid determination in a well bore |
| US10329898B2 (en) | 2010-11-19 | 2019-06-25 | Zenith Oilfield Technology Limited | High temperature downhole gauge system |
| WO2020225274A2 (en) | 2019-05-07 | 2020-11-12 | Roxar Flow Measurement As | System and method for providing measurements in a pipe |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1135570A (en) * | 1964-12-17 | 1968-12-04 | Schlumberger Prospection | Improvements in apparatus adapted for use in measuring the dielectric constant of a fluid |
| GB1466768A (en) * | 1974-05-13 | 1977-03-09 | Cmelik R | Apparatus for measuring the water content of oil |
| GB2118723A (en) * | 1982-04-19 | 1983-11-02 | Dresser Ind | Method and apparatus for determining characteristics of a multi-phase flow regime |
| EP0372598A2 (en) * | 1988-12-03 | 1990-06-13 | Schlumberger Limited | Impedance cross correlation logging tool |
-
1991
- 1991-06-28 GB GB9114000A patent/GB2246866A/en not_active Withdrawn
- 1991-07-17 NO NO91912802A patent/NO912802L/en unknown
- 1991-08-06 BR BR919103383A patent/BR9103383A/en not_active Application Discontinuation
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1135570A (en) * | 1964-12-17 | 1968-12-04 | Schlumberger Prospection | Improvements in apparatus adapted for use in measuring the dielectric constant of a fluid |
| GB1466768A (en) * | 1974-05-13 | 1977-03-09 | Cmelik R | Apparatus for measuring the water content of oil |
| GB2118723A (en) * | 1982-04-19 | 1983-11-02 | Dresser Ind | Method and apparatus for determining characteristics of a multi-phase flow regime |
| EP0372598A2 (en) * | 1988-12-03 | 1990-06-13 | Schlumberger Limited | Impedance cross correlation logging tool |
Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5453693A (en) * | 1993-10-01 | 1995-09-26 | Halliburton Company | Logging system for measuring dielectric properties of fluids in a cased well using multiple mini-wave guides |
| GB2313196A (en) * | 1996-05-15 | 1997-11-19 | Western Atlas Int Inc | Downhole multiphase flow sensor |
| GB2313196B (en) * | 1996-05-15 | 2000-11-22 | Western Atlas Int Inc | Downhole multiphase flow sensor |
| GB2471108B (en) * | 2009-06-17 | 2013-08-07 | Vetco Gray Controls Ltd | Monitoring of undesirable fluid ingress into subsea control modules |
| GB2478232A (en) * | 2009-06-17 | 2011-08-31 | Vetco Gray Controls Ltd | Monitoring of undesirable fluid ingress into subsea control modules |
| GB2478232B (en) * | 2009-06-17 | 2011-12-07 | Vetco Gray Controls Ltd | Monitoring of undesirable fluid ingress into subsea control modules |
| GB2471108A (en) * | 2009-06-17 | 2010-12-22 | Vetco Gray Controls Ltd | Monitoring of undesirable fluid ingress into subsea control modules |
| EP2278121A3 (en) * | 2009-06-17 | 2016-11-09 | GE Oil & Gas UK Limited | Monitoring of undesirable fluid ingress into subsea control modules |
| US10329898B2 (en) | 2010-11-19 | 2019-06-25 | Zenith Oilfield Technology Limited | High temperature downhole gauge system |
| EP2574722A1 (en) * | 2011-09-28 | 2013-04-03 | Welltec A/S | A downhole sampling tool |
| GB2495132A (en) * | 2011-09-30 | 2013-04-03 | Zenith Oilfield Technology Ltd | Fluid mixture determination |
| WO2013045913A3 (en) * | 2011-09-30 | 2013-09-26 | Zenith Oilfield Technology Limited | Fluid determination in a well bore |
| GB2495132B (en) * | 2011-09-30 | 2016-06-15 | Zenith Oilfield Tech Ltd | Fluid determination in a well bore |
| US9541665B2 (en) | 2011-09-30 | 2017-01-10 | Zenith Oilfield Technology Limited | Fluid determination in a well bore |
| US9541436B2 (en) | 2011-11-22 | 2017-01-10 | Lufkin Industries, Llc | Distributed two dimensional fluid sensor |
| US10107789B2 (en) | 2013-03-11 | 2018-10-23 | Zenith Oilfield Technology Limited | Multi-component fluid determination in a well bore |
| WO2015055767A1 (en) | 2013-10-16 | 2015-04-23 | Roxar Flow Measurement As | Scale monitoring and inhibitor quantification technique in multiphase meters |
| US9759646B2 (en) | 2013-10-16 | 2017-09-12 | Roxar Flow Measurement As | Scale monitoring and inhibitor quantification technique in multiphase meters |
| CN108442920A (en) * | 2018-02-08 | 2018-08-24 | 天津大学 | The water phase conductivity measuring apparatus of aqueous phase multiphase flow in upward vertical tube |
| CN108442920B (en) * | 2018-02-08 | 2021-07-06 | 天津大学 | Water phase conductivity measuring device for water-containing phase multi-phase flow in vertical riser |
| WO2020225274A2 (en) | 2019-05-07 | 2020-11-12 | Roxar Flow Measurement As | System and method for providing measurements in a pipe |
| EP4030148A2 (en) | 2019-05-07 | 2022-07-20 | Roxar Flow Measurement AS | System and method for providing measurements in a pipe |
| US11959785B2 (en) | 2019-05-07 | 2024-04-16 | Roxar Flow Measurement As | System and method for measuring a multiphase flow by measuring density and electrical impedance for correcting the measurement due to effect of deposits on inner surface of pipe walls |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9114000D0 (en) | 1991-08-14 |
| NO912802L (en) | 1992-02-07 |
| BR9103383A (en) | 1992-05-12 |
| NO912802D0 (en) | 1991-07-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |