RU2348804C2 - Borehole hydro-stream power meter - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: proposed invention pertains to borehole drilling, meant for determining the hydraulic capacity of a water course in it and can be used for solving problems related to design and operation of energy source equipment, fitted in wells, the principle of operation of which involves conversion of energy of a borehole water courses into heat energy. The hydro-stream power meter comprises a borehole caliper, connected through a borehole cable, to a ground converter-display unit, and a depth gauge, connected to a counterweight. The borehole calliper has a flow transducer through a non-packer type borehole calliper Q, a pressure transducer, and a borehole diameter transducer, connected to the borehole cable. The borehole calliper has a simulator of hydro resistance of a hydro power plant, either connected to the borehole caliper in its bottom part, or fitted in the borehole in the subsequent place of its operation. The converter-display unit determines the compensation factor of the diameter of the borehole K_d, in at the measuring point, executes a function in accordance with a mathematical expression. Use of the device increases accuracy of measuring power of a borehole hydro-stream, and consequently, using the measuring results, the best decisions on designing and operating borehole hydro energy sources can be taken.

EFFECT: increased accuracy of measuring borehole hydro-stream.

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Description

The claimed invention relates to drilling, is intended to determine the hydraulic power of the watercourse in it and can be used to solve the design and operation of equipment of energy sources installed in the wells, the principles of which provide for the conversion of energy of borehole watercourses into electrical or thermal energy.

Known borehole hydroelectric power station (Generation of electricity during the injection of a denste fluid into a subterranean formation. Patent US 4132269 A, CL E21 B 43/20, F03G 7/04, published 02.01.1979 [1]), which includes a water source connected to the feed tank, a conduit in communication with it, the lower end of which is connected to a drainage zone located below the point of communication of the conduit with the feed tank, a hydraulic machine installed in the lower part of the conduit, for example, a hydraulic turbine kinematically connected to an electric generator. In it, the water conduit is formed by a mine working - a borehole drilled to the drainage zone, the surface water reservoir in the zone of which the well is drilled, or the underground aquifer zone or zones, or the surface water reservoir with an underground zone or zones, the water conduits are equipped with water flow control devices , for example, by control valves, and the electric generator is communicated with a cable installed in the borehole with a day surface at the wellhead.

In it, the hydraulic energy of the borehole water stream is converted by the borehole hydropower unit into electrical energy, which is transmitted by cable to the surface, is converted to the required quality, distributed and released to the consumers.

Known heat supply well (Heat supply well. RF patent No. 2291255. M. CL EV03/00; F24H 4/02. Auth. Eliseev AD Publ. 20.01.2007, bull. No. 1, [2]) containing a water source connected to a nutrient tank, a conduit in communication with it, a lower end of which is connected to a drainage zone, a heat generator and a heat consumer installed in the conduit. In a mountainous area with a mountain slope or with a lower adit, a directional or deviated well is drilled, which serves as a water conduit, so that its slope crosses the mountain slope and is associated with the day surface, or the roof of the adit below. In this case, the surface water reservoir in the zone of which the well is drilled, or the underground aquifer zone or zones, or the surface water reservoir with the underground zone or zones are taken as the source of water, the intersection of the well with the mountain slope — the day surface or the intersection of the well with the downhole adit, is taken as a heat generator, a vortex heat generator is adopted, which is installed at a dynamic level and a water pressure sufficient for its operation, and the heat consumer is connected in the well flow zone through its piping .

In it, the hydraulic energy of the borehole water stream is converted by the borehole hydropower unit into thermal energy in hot water, which is transmitted through a pipeline (laid in the downstream adit) to the output collector, distributed and released to heat consumers.

The power of the water flow (hydraulic power) in the channel, including the borehole, is determined according to the following expression (Karelin V.Ya. et al. Hydropower stations. Edited by Prof. V.Ya. Karelin and G.N. Krivchenko. M ., Energy Publishing House, 1987 [3]):

N _g - hydraulic power of the water flow, W;

P is the water pressure in the channel at the installation site of the hydropower unit, Pa;

Q - water flow in the channel, at the installation site of the hydroelectric power unit, m ³ / s.

Similarly to expression (1), the hydraulic power of the water flow at any point in the well can be determined.

A review of patent and technical information found that there are no instruments for measuring the hydraulic power of water flows in the well (at various points in depth). This does not allow to quickly and efficiently resolve issues related to the design and operation of downhole hydraulic energy sources.

For the study of hydrodynamic processes in wells, it is known to use instruments for measuring individual parameters of water (or oil) flows in wells, including flow rate - a borehole flow meter or flow meter, pressure - a borehole pressure gauge (Petrov A.I. Depth instruments for researching wells. M ., Nedra, 1988 [4]). In principle, their application allows you to determine the power of the hydraulic water flow in the well by measuring flow and pressure at points of interest in the well and subsequent calculations according to expression (1).

To reduce the measurement errors of indicators determined using the parameters measured by measuring instruments of individual parameters (due to errors in the binding of the obtained results in depth; due to a possible change in time of the hydrodynamic flow regime, etc.) obtained by separate descent and ascent of the downhole sensor , and to reduce research time, aggregated, complex devices are known. With one descent of the downhole sensor of such an instrument into the well at each point in the well, several parameters are measured simultaneously ([4], pp. 77-106), including the flow rate and pressure of the water - the Potok-5 device ([4], p. 80-82). In the downhole sensor of the Potok-5 device, the flow transducer is made in the form of a braked turbine, and the pressure transducer is made in the form of a helix spring. Electrical signals from the transducers of water flow and its pressure are fed through a logging cable to the surface - to the surface measuring and recording unit, in which the values of individual parameters (flow and pressure) are continuously displayed on the scale of the device and recorded. Measured parameters (flow rate and pressure) in the complex control device by eliminating errors of deep mismatch of measurements (which is typical for separate measurement of parameters) and by observing the same hydrodynamic regime (since measurements are not synchronized, which is typical for separate measurement and descent of the sensor of each of the parameters) have greater accuracy (less likely to distort the measurement result). The use of a comprehensive monitoring device reduces the time required to perform measurements.

The Potok-5 integrated control device for measuring water flow in well sections with different diameters (in caverns) is equipped with an umbrella type packer. Its use in the device allows the entire flow of water, regardless of its diameter, to be directed into the calibrated measuring channel of the downhole tool and thereby eliminate the effect of the diameter of the well on the result of the flow measurement. However, the use of a packer in a downhole tool introduces distortion into the hydrodynamic regime of the water flow in the well - it increases the hydraulic resistance in the flow path and can affect the position of the water level in the well. The change in the hydrodynamic regime of the water flow is also reflected in the value of the power of its flow, i.e. distorts its real (actual) meaning. Based on the foregoing, to increase the accuracy of flow measurement in a comprehensive control device, a tubeless well flow meter should be used.

It is known to use tubeless flow meters (Gershanovich IM Hydrogeological studies in wells by flow metering method. M., Nedra, 1981 [5]), the use of which practically does not distort the hydrodynamic mode of the borehole flow during measurements and this does not increase the corresponding component of the measurement error downhole flow rate.

Closest to the proposed power meter of a borehole hydraulic flow is a borehole flowmeter (Borehole flowmeter. RF Patent No. 1657635. M. CL E21V 47/10. Auth. Eliseev A.D., Pakulov V.G. Publ. 02.22.91, Bulletin No. 6 [6]), adopted as a prototype. It includes a downhole sensor, a ground transducer showing block connected to it via a downhole cable, a depth gauge connected to a block balance, the downhole sensor includes a flow rate transducer through a downhole type downhole sensor, a pressure transducer, a borehole diameter transducer connected to the downhole cable. With one descent, ascent of the downhole sensor, the device allows you to simultaneously determine the values of: the diameter of the well; pressure at the measuring point; flow rate through the downhole sensor at various depth points of the well. Knowing the value of the measured flow rate through the downhole sensor (determined by the rotational speed of the impeller Q = n / С _t , where n is the rotational speed of the impeller when measuring flow, r / s; С _t - calibration coefficient of the device, l / s · rev) Q, the diameter of the well at the measuring point d and having the value of the calibration coefficient of the downhole sensor C _t determine the value of the correction coefficient K _d from the diameter of the well (Ivachev L.M. Fighting the absorption of flushing fluid when drilling exploration wells. M., Nedra, 1982, p. 45-54 [7]). The value of the measured water flow through the entire cross section of the well at the measuring point is determined from the following ratio:

The disadvantage of the prototype is as follows:

- when using it, the conditions for the presence of a downhole hydropower converter (downhole hydraulic unit or downhole thermal vortex generator) in the well are not simulated. In this case, additional hydroresistances are formed that affect the hydrodynamic conditions for the existence of a water flow in the well, and, as a result, are reflected in its (measured) power, and this neglect leads to an increase in the error of its measurements;

- the existing procedure for determining the correction coefficient from the well diameter K _d , which provides for the graphic processing of the obtained measurement results, is associated with the appearance of an additional error of indirectly obtaining the result of measuring the flow rate in the well, the value of which is subjective and depends on the individual qualities and state of the observer. It can be a significant amount.

The technical solution to which the claimed invention is directed is the creation of a borehole hydraulic flow power meter with greater accuracy in comparison with the prototype.

The technical solution is achieved by the fact that in a downhole power meter including a downhole sensor connected to it via a downhole cable, a ground-based transducer-showing unit, a depth gauge connected to a balance-sheet, the downhole sensor contains a flow rate transducer through the downhole type Q sensor, a transducer pressure transducer, diameter of the borehole connected to the borehole cable, the borehole sensor is equipped with a simulator of hydraulic rotation of the borehole hydropower unit, or Integrated with the downhole sensor in its lower part, or installed in the well in the place of its subsequent operation, the conversion-indicating unit determines the correction factor from the well diameter K _d and implements a function at the measured point according to the following expression:

N _g = P · Q · K _d , where

N _g - measured hydraulic power flow in the well, W;

P is the water pressure at the measurement point, Pa;

Q is the flow rate through the measuring channel of the sensor at the measuring point, m ³ / s;

K _d - correction factor from the diameter of the well.

The drawing shows a diagram of a power meter of a borehole hydroflow in a well of hydropower designation, where the following designations are introduced: 1 - borehole; 2 - the first aquifer; 3 - second aquifer; 4 - pipeline connecting the well with a surface water source; 5 - absorbing zone; 6 - water flow in the well; 7 - dynamic water level in the well N _d1 ; 8 - installation site in the well of a hydroelectric power unit (GEA); 9 - simulator GEA; 10 - downhole tool - measuring power downhole flow; 11 - impeller of the flow transducer; 11.1 - impeller shaft; 11.2 - mechanoelectric flow transducer; 12 - centering springs - diameter sensor; 12.1 - mechanical connection of the diameter sensor with the core of the diameter transducer of the well; 12.2 - core diameter transducer of the well; 12.3 - mechanoelectric transducer of borehole diameter; 13.1 - pressure sensor - helicoidal tube; 13.2 - the core of the pressure transducer; 13.3 - pressure transducer; 14 - socket suspension of cargo; 15 - downhole cable; 16 - casing string; 17 - valve; 18 - block balance, combined with a depth gauge; 19 - ground conversion display unit; N _d1 - dynamic level, N _d2 - pressure level.

A well 1 of hydropower designation was drilled, the drilling diameter was 190 mm. The well was drilled to the absorption zone 5. During the drilling process, the first 2 and second 3 water-bearing intervals were drilled. Downhole flow measurement of drilled aquifers determined the position of their boundaries and flow rates. Their total flow rate was Q ₁ = 0.01 m ³ / s. To generate the required (determined by a preliminary estimate) hydraulic power of the flow at the installation site of the downhole hydropower unit, water was supplied from the surface source to the wellhead 4 (with valve 17). The flow rate of water from a surface source is Q ₁ = 0.01 m ^{3 /} s. Thus, it is tentatively estimated that the flow rate (total) of the water of the hydropower flow in the well is Q ₁ = 0.02 m ³ / s. To ensure the necessary operating conditions for the water supply well, its aquifers are equipped with casing 16 and filters, i.e. the well was developed as a water supply.

Before performing measurements of the power of the borehole hydraulic flow into the well in the form of a perforated pipe section, a simulator of hydroresistance is introduced to the bottom of the well, which is introduced by the hydroelectric power unit into the hydrodynamic mode in the well during its operation (hereinafter GEA simulator), at the point of its subsequent operation. The GEA simulator is a segment of the annular section profile with a certain hydroresistance created by the GEA at its rated power.

Water flows from water supply pipe 4 and from water-bearing intervals 2 and 3 enter the well and move to its drainage zone — absorption zone 5. At the same time, at a depth of N _d1 = 320 m from the wellhead, a dynamic level is established below which a continuous flow is formed in the well - hydropower flow. He created the flow head N _d2 = 450 m.

Downhole (logging) cable 15, passed through the block balance with the depth gauge 18, the downhole sensor of the power meter of the borehole hydraulic flow 10, then IMSG-P, is lowered.

The inventive IMSG-P works as follows.

Measuring the power of a borehole hydroflow with a simulator of a borehole hydroflow of a downhole GEA installed in the borehole.

With a simulator of downhole GEA 9 installed in well 1 in the place of its subsequent operation and stabilized dynamic level in well 7, its value is determined from the pressure measured by the IMSG-P device by moving the downhole sensor up and down along the position of the presence-absence pressure boundary depth. He was N _d1 = 320 m.

The downhole sensor 10 of the IMSG-P device lowers to the installation point of the GEA simulator and is maintained in this position with a "working" well for 10-15 minutes (time sufficient to stabilize the hydrodynamic flow regime in the well). To the downhole cable 15 connect the ground conversion-indicating unit 19 and measure the power of the downhole hydraulic flow.

Pressure measurement channel. The water pressure of the stream, which is the sum of the pressure of the water column located above the downhole sensor, and the pressure loss when the stream moves in the well into the absorption zone, is perceived by a helicoidal tube 13.1, one end of which is rigidly fixed to the body of the downhole sensor 10.

Under the influence of the measured pressure, the helicoidal tube tries to straighten and unwind, while the other end of the tube, to which the core of the pressure transducer 13.2 is attached, is more susceptible to movement. With the movement of this end of the tube, the core of the pressure transducer 13.2 moves, interacting with the pressure transducer 13.3, which causes a change in the signal (voltage) acting on it. A signal proportional to the measured pressure And _p through the downhole cable 15 is transmitted to the ground conversion display unit (hereinafter NPPB) 19. The value of the measured pressure is displayed on a digital pressure indicator, it is 4.41 MPa. The signal And _p , in addition, in NPPP goes to the circuit for calculating the measured power of the borehole hydraulic flow.

Diameter measurement channel. At the installation site of the downhole sensor 10, the centering springs - diameter sensor 12 take a state corresponding to the diameter of the well at the measurement point. The springs are rigidly connected to the core 12.1 of the diameter transducer, which interacts with a mechoelectric transducer of diameter 12.3. The measured diameter of the well corresponds to a specific position of the core 12.1 in the mechanoelectric transducer 12.3. A voltage proportional to the measured diameter of the borehole And _d acts on the mechanoelectric transducer of diameter 12.3. The signal corresponding to the measured diameter And _d , through the downhole cable 15 is transmitted to NPPB 19. The value of the measured diameter is displayed on a digital indicator of the diameter of the block. The diameter is 191 mm.

In addition, in NPPB, the signal And _d enters the circuit for calculating the measured power of the borehole hydraulic flow - to the first input of its node for forming a correction for the diameter of the borehole. (A signal proportional to the diameter of the downhole sensor is inputted at the other input of the node for forming a correction for the diameter of the well).

Flow measurement channel. A continuous hydraulic flow established in a well below a dynamic level of 7 has hydraulic power, which hydropower unit, in potential, can be converted into electric or thermal energy. Along with the pressure of the medium, an important factor determining the hydraulic power of a borehole hydraulic flow is its flow rate (see formula 1).

The sensor 10 of the IMSG-P device senses the speed and flow rate of only a fraction of the flow that passes through the cross-section of the downhole sensor 10. The impeller of the downhole flow sensor is an impeller 11, the shaft of which 11.1 creates a sign of its rotation speed. When the impeller 11 rotates, its rotating shaft 11.1 interacts with the flow transducer 11.2, on which a signal with voltage AND _Q is proportional to the rotational speed of the impeller and the measured flow rate through the sensor Q.

A signal proportional to the flow rate of the water through the sensor of the device And _Q is transmitted through the downhole cable 15 to the NPPB 19. The value of the measured flow rate through the downhole sensor Q is displayed on the digital flow indicator through the downhole sensor. The measured flow rate is Q = 3.85 · 10 ^-3 m / s.

In addition, the signal And _Q , proportional to the flow rate through the downhole sensor, enters the circuit for calculating the power of the downhole hydraulic flow.

Two signals are received at the node for correcting the diameter of the well: one from the transducer of the diameter of the downhole sensor And _d , the other is entered by the switch and its value is proportional to the diameter of the downhole sensor. The node automatically calculates the value of K _d (the dependences of K _d on the borehole diameter for a particular borehole sensor — its diameter, according to the dependence in Fig. 6 [7], p. 50) are automatically processed, and a signal proportional to it is fed to the power calculation circuit downhole hydroflow.

For the example in question:

P ₁ = 4.41 MPa; D ₁ = 191 mm; Q ₁ = 3.85 · 10 ^-3 m ³ / s; K _d = 5.2.

On the digital indicator of the device IMSG-P, the measured value of the indicated power of the borehole hydraulic flow is displayed. Power is equal to N _g1 = 88.2 kW.

Measuring the power of a borehole hydroflow without a simulator of a borehole hydropower unit. Raise from the well using an emergency tool (tap) simulator downhole GEA.

The downhole sensor 10 is lowered into the well 1 on the downhole cable 15 and installed in the place of the subsequent (supposed) operation of the GEA. Save the previously established (similar to the previous measurement, with a simulator GEA) water flow from pipeline 4 and from aquifers 2 and 3.

After 10-15 minutes, in the same sequence as the previous version, the power of the borehole hydraulic flow and the parameters characterizing it were measured. They amounted to:

P ₂ = 4.35MPa; D ₂ = 191 mm; 02 = 4.2 · 10 ^-3 m ³ / s; K _d = 5.2; N _g2 = 95.2 kW.

Based on the results of the measurements N _g1 = 88.2 kW, and N _g2 = 95.2 kW. From the comparison it follows that N _r1, measured downhole hydraulic resistance simulator HEV less measurement result performed without N _z2 ceteris paribus 7.3%.

The inventive IMSG-P allows you to more accurately determine the power of the borehole hydraulic flow, and the use of the results of more accurate measurements creates the prerequisites (information) to make more correct decisions at the subsequent stages of the design and operation of borehole hydropower sources of energy.

In addition, the exclusion of the observer from the procedure for determining the correction coefficient from the borehole diameter K _d , which provides for the graphic processing of the obtained measurement results, associated with the appearance of an additional error of indirectly obtaining the result of measuring the watercourse power in the borehole, the magnitude of which is subjective and depends on the individual qualities and state of the observer, also allows you to reduce this component of the error, which can be a significant amount.

INFORMATION SOURCES

1. Generation of electricity during the injection of a denste fluid into a subterranean formation. US Pat. No. 4,132,269 A, Cl. ЕВВ 43/20, F03G 7/04, publ. 01/02/1979

2. Heat supply well. RF patent No. 2291255. M. cl. EV03 3/00; F24H 4/02. Auth. Eliseev A.D. Publ. 01/20/2007, bull. No. 1.

3. Karelin V.Ya. and other hydropower stations. Edited by prof. V.Ya. Karelina and G.N. Krivchenko. M., Energy Publishing House, 1987

4. Petrov A.I. Depth instruments for well research. M., Nedra, 1988

5. Gershanovich I.M. Hydrogeological studies in wells by flow metering. M., Nedra, 1981

6. Downhole flowmeter. RF patent No. 1657635. M. cl. ЕВВ 47/10. Aut.Eliseev A.D., Pakulov V.G. Publ. 02/22/91, bull. No. 6 is a prototype.

7. Ivachev L.M. The fight against the absorption of flushing fluid while drilling exploration wells. M., Nedra, 1982

Claims (1)

A downhole hydraulic flow power meter including a downhole sensor, a ground-based transducer-block connected to it via a downhole cable, a depth gauge connected to a block balance, and a downhole sensor includes a flow rate transmitter through a downhole type Q sensor, a pressure transducer, a borehole diameter transducer connected with a downhole cable, characterized in that the downhole sensor is equipped with a simulator of hydraulic resistance of a downhole hydropower unit or a connection nym with a downhole sensor in its lower part, or set in the well in place subsequent operation, converting-indicating unit determines a correction factor of hole diameter K _d and the measured point implements the function according to the following expression: N _g = P · Q · K _d where
N _g - measured hydraulic power of the hydraulic flow in the well, W;
P is the water pressure at the measurement point, Pa;
Q is the flow rate through the measuring channel of the sensor at the measuring point, m ³ / s;
K _d - correction factor from the diameter of the well.