CN1323223C - Water, sand, air measurement device and method for multiphase fluids in air drilling - Google Patents

Abstract

The invention discloses a measuring device and method for water, sand and air discharge in air drilling. The device includes a gas-liquid-solid separator and an inverted U-shaped pipe connected to the pipeline of water, sand and air discharge The ascending section of the inverted U-shaped pipe has a first differential pressure sensor, and the descending section is provided with a second differential pressure sensor; the inverted U-shaped pipe is connected to the outlet of the discharge pipeline through a Venturi tube and a mixer installed on the pipeline; -The liquid-solid separator is provided with a one-way valve, a pressure gauge and a Venturi nozzle in sequence, and communicates with the mixer through a pipeline; the pressure gauge, the Venturi tube nozzle, the Venturi tube, the first differential pressure sensor, the second pressure The difference sensors are also respectively connected with the computer. The Venturi tube nozzle is used to measure the gas flow rate, and the gas density is corrected by the pressure gauge. The Venturi tube measures the pressure difference on both sides of the inverted U-shaped tube to obtain the ratio of water and sand; the computer solves it simultaneously according to the multiphase fluid theory , the volume or weight flow of water and sand can be obtained.

Description

Water, sand, air measurement device and method for multiphase fluids in air drilling

technical field

The invention belongs to measuring instruments in the technical field of petroleum production, and relates to a flow measuring method and device, in particular to a water, sand and air measuring device and method for multiphase fluids in air drilling.

Background technique

Drilling with air-cooled drill bits is a new technology and method for natural gas extraction. Compared with mud-cooled drill bits, this new technology has the advantages of high drilling speed and low cost. A key technology for applying this new method is to measure and monitor the flow rate of the drilling discharge—gas, water, and sand, so as to monitor the geological state during the drilling process at any time. At present, there is no effective method to monitor the flow of gas, water and sand. It can only be estimated and qualitative calculation, and there is no accurate method that can be applied. So far, there is no gas-liquid-solid three-phase flow device that can measure gas-water-sand on-line at home and abroad. The method and device of gas/water/sand gas-liquid solid-state three-phase flow can be used to understand the instantaneous flow and cumulative flow of gas, water, and sand during drilling, which is of great significance for gas drilling.

Contents of the invention

The object of the present invention is to provide a measuring device for continuously measuring the flow of water, sand and air in a multiphase fluid on-line and provide a measuring method.

In order to achieve the above object, the technical solution adopted by the present invention is: a water, sand and air measuring device for multiphase fluid in air drilling, including a gas-liquid-solid separator, characterized in that the gas-liquid-solid separator One end is connected to the multi-phase fluid pipeline, and the other end is connected to an inverted U-shaped tube. The ascending section of the inverted U-shaped tube has a first differential pressure sensor, and the descending section is equipped with a second differential pressure sensor; the inverted U-shaped tube passes through A Venturi tube and a mixer arranged on the pipeline are connected to the outlet of the discharge pipeline;

The gas-liquid-solid separator is provided with a one-way valve, a pressure gauge and a Venturi nozzle in sequence, and communicates with the mixer through a pipeline;

The pressure gauge, the Venturi tube nozzle, the Venturi tube, the first differential pressure sensor and the second differential pressure sensor are respectively connected with the computer.

The measurement method of the above-mentioned measuring device is characterized in that, comprising the following steps:

1) The multiphase fluid enters the gas-liquid-solid separator first, and the gas is separated from water and sand in the gas-liquid-solid separator, and the gas flows upward through the gas one-way valve, pressure gauge and Venturi tube nozzle to measure the gas flow. Enter the mixer, and the gas density is corrected by the pressure gauge. The gas one-way valve only allows the gas to flow through, preventing the water and sand mixture from flowing out;

2) The mixture of water and sand passes through the inverted U-shaped pipe, and the pressure difference sensors set in the ascending section and descending section of the inverted U-shaped pipe, and the pressure difference on both sides of the inverted U-shaped pipe is measured by the Venturi tube to obtain water, Sand ratio;

3) The computer solves simultaneously according to the multiphase fluid theory, and the volume or weight flow of water and sand can be obtained.

The water, sand and air measuring device and method for multiphase fluids in air drilling of the present invention solve the difficult problem of measuring the flow rate of water, sand and air discharge in air drilling, with high measurement accuracy and reliable data, and the entire measurement process is controlled by a computer , can be measured online.

Description of drawings

Accompanying drawing 1 is the structural principle diagram of the present invention.

Below in conjunction with accompanying drawing, the present invention will be further described

Detailed ways

Referring to accompanying drawing, the measuring device of water, sand, air of multiphase fluid in the air drilling of the present invention comprises gas-liquid-solid separator 1, and one end of this gas-liquid-solid separator 1 is connected with the pipeline of multiphase fluid , the other end is connected with an inverted U-shaped pipe 4, the rising section of the inverted U-shaped pipe 4 has a first differential pressure sensor 9, and its descending section is provided with a second differential pressure sensor 10; A venturi 5 and a mixer 6 are connected to the outlet of the effluent line;

The gas-liquid-solid separator 1 is provided with a one-way valve 2, a pressure gauge 8 and a Venturi nozzle 3 in sequence, and communicates with the mixer 6 through a pipeline;

The pressure gauge 8 , the Venturi nozzle 3 , the Venturi tube 5 , the first differential pressure sensor 9 , and the second differential pressure sensor 10 are also connected to the computer 7 respectively.

The multi-phase fluid first enters a compact structure and high-efficiency gas-liquid-solid separator 1, which separates gas from water and sand. The gas flows upward through the gas one-way valve 2. The valve 2 only allows the gas to flow through and prevents the water-sand mixture from flowing out. The gas flow rate is measured with a Venturi nozzle 3 of a single-phase flowmeter. Pressure gauge 8 is used to correct gas density.

${\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\sqrt{\frac{\mathrm{<span\; class="notranslate">\; \&Delta;\&rho;</span>}}{{\mathrm{<span\; class="notranslate">\; \&rho;</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

In the formula, C is the flow coefficient, _Qt is the gas density under the working condition, which is corrected by the pressure p, and A is the throat area of the Venturi nozzle;

The inverted U-shaped pipe 4 is used to measure the density of the water-sand mixture. When the water and the sand mixture flow through the rising section of the inverted U-shaped pipe (4), the pressure is measured by the first differential pressure sensor 9 on the rising section of the two vertical pipes. ρ ₁ , the second differential pressure sensor 10 in the descending section measures the differential pressure ρ ₂ , which is the sum of the gravity differential pressure and the friction differential pressure of the mixture. Its formula is as follows:

Δρ ₁ =ρ _f +Δρ _m gh (2)

Δ ₂ = Δρ _f - Δρ _m gh (3)

In the formula, ρ is the density of water-sand mixture, h is the height of differential pressure measurement, ρ _is the pressure difference of frictional resistance, and _ρ is the density of water-sand mixture;

From formula (2), (3) can get:

Δρ _m = (Δρ ₁ −Δρ ₂ )/2gh (4)

Also, Δρ _m =k _w ×ρ _s +k _w ×ρ _w (5)

In the formula, Ks and Kw are the relative ratios of sand and water, and ρs _{, ρs} are the densities of sand and water.

because:

k _s +k _w ＝1 (6)

The relative ratios k _w and k _s of water and sand can be obtained from formulas (5) and (6).

The water-sand mixture measures the water-sand volume flow rate with Venturi tube 5:

${\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; S</span>}<span\; class="notranslate">\; \&times;</span>\sqrt{\frac{\mathrm{<span\; class="notranslate">\; \&Delta;\&rho;</span>}}{{\mathrm{<span\; class="notranslate">\; \&Delta;\&rho;</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span>$

In the formula: Δρ is the pressure difference between the differential pressure sensor 9 and the differential pressure sensor 10, C is the flow coefficient, and S is the throat area of the Venturi tube.

The volume or weight flow of water and sand can be obtained from the mixture density and the volume flow of water-sand mixture:

Q _w =k _w ×Q _t (8)

Q _w =k _s ×Q _t (9)

The entire measurement process is controlled and processed by the computer 7, and is fully automated.

Claims (2)

1. Water, sand, air measuring device of multiphase fluid in a kind of air drilling, comprise gas-liquid-solid separator (1), it is characterized in that, one end of this gas-liquid-solid separator (1) and water, sand , The pipeline connection of the air discharge, the other end is connected with an inverted U-shaped pipe (4), the ascending section of the inverted U-shaped pipe (4) has a first differential pressure sensor (9), and the descending section is provided with a second pressure sensor (9). The difference sensor (10); the inverted U-shaped pipe (4) is connected to the outlet of the discharge pipeline through the Venturi tube (5) and the mixer (6) arranged on the pipeline; The gas-liquid-solid separator (1) is sequentially provided with a one-way valve (2), a pressure gauge (8) and a Venturi nozzle (3), and communicates with the mixer (6) through a pipeline; The pressure gauge (8), the Venturi tube nozzle (3), the Venturi tube (5), the first differential pressure sensor (9), and the second differential pressure sensor (10) are also respectively connected with the computer (7). 2. a water, sand, air measuring method of multiphase fluid in air drilling, it is characterized in that, the method adopts the device described in claim 1, and its measuring method comprises the following steps: 1) The multiphase fluid enters the gas-liquid-solid separator first, and the gas is separated from water and sand in the gas-liquid-solid separator, and the gas flows upward through the gas one-way valve, pressure gauge and Venturi tube nozzle to measure the gas flow. Enter the mixer, and the gas density is corrected by the pressure gauge. The gas one-way valve only allows the gas to flow through, preventing the water and sand mixture from flowing out; 2) The mixture of water and sand passes through the inverted U-shaped pipe, and the pressure difference sensors set in the ascending section and descending section of the inverted U-shaped pipe, and the pressure difference on both sides of the inverted U-shaped pipe is measured by the Venturi tube to obtain water, Sand ratio; 3) The computer solves simultaneously according to the multiphase fluid theory, and the volume or weight flow of water and sand can be obtained.