A device and method for measuring water content in oil wells

Abstract

The present invention discloses a device for measuring the water content of an oil well, comprising a storage cylinder, the storage cylinder can input and discharge crude oil in a wellhead oil storage tank, an ultrasonic probe b is arranged on the inner bottom surface of the storage cylinder, a top cover is arranged on the top of the storage cylinder, an ultrasonic probe a is arranged on the inner top surface of the top cover, and both the ultrasonic probe b and the ultrasonic probe a are connected to a host computer, and the device has the characteristics of small sampling result error and accurate water content measurement result. The present invention also discloses a measuring method for the device for measuring the water content of an oil well, and the measuring result is accurate, which improves the working efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of oil field testing, relates to an oil well water content measuring device, and also relates to a measuring method of the oil well water content measuring device. Background Art

[0002] The water content of oil wells is a necessary production parameter and technical indicator in oilfield development. A large number of oil wells in oil fields use oil storage tanks placed at the wellheads and vehicles to transport produced fluids, with a daily output of only a few hundred kilograms. In addition, the water content varies greatly when the fluid is added. Testing the water content depends entirely on manual sampling, and physical or chemical methods such as distillation and electro-desorption are used to separate oil and water and calculate the water content of crude oil. There are various problems such as inaccurate sampling, cumbersome testing procedures, and low work efficiency. As a result, the water content data of oil wells is completely distorted, which brings great inconvenience to the decision-making of measures adjustment in oilfield development. In addition, the work of unmanned operation and automated management of oil wells cannot be promoted. At the same time, due to the limitation of input-output ratio, there is currently no relevant technology that can meet the promotion conditions of all-round requirements such as automatic testing, reliable data, and appropriate prices. Summary of the invention

[0003] The first object of the present invention is to provide an oil well water content measuring device, which has the characteristics of small sampling result error and accurate water content measurement result.

[0004] The second object of the present invention is to provide a measuring method of an oil well water content measuring device.

[0005] The technical solution adopted by the present invention is a device for measuring the water content of an oil well, including a storage cylinder, which can input and discharge crude oil in a wellhead oil storage tank, an ultrasonic probe b is arranged on the inner bottom surface of the storage cylinder, a top cover is arranged on the top of the storage cylinder, an ultrasonic probe a is arranged on the inner top surface of the top cover, and both the ultrasonic probe b and the ultrasonic probe a are connected to a host computer.

[0006] The present invention is also characterized in that:

[0007] The storage cylinder comprises an inner cylinder and an outer cylinder, a heating layer is arranged on the outer side wall of the inner cylinder, and insulating sealant is filled between the outer cylinder and the heating layer.

[0008] The heating layer is a silicone rubber heating sheet, and the silicone rubber heating sheet is connected to the host computer.

[0009] A temperature detector is arranged on the inner bottom surface of the inner cylinder, and the temperature detector is connected to the upper computer. The connection lines between the temperature detector, ultrasonic probe b, ultrasonic probe a, silicone rubber heating sheet and the upper computer are all located in the insulating sealant.

[0010] A liquid inlet groove is opened on the side wall of the storage cylinder, the liquid inlet groove runs through the side wall of the storage cylinder horizontally, and the liquid inlet groove runs from the opening of the storage cylinder to the bottom of the storage cylinder vertically. A sealing airbag is provided on any side wall of the liquid inlet groove, the sealing airbag is connected to an air inlet and exhaust pipe, the air inlet and exhaust pipe is connected to an air pump, and the air pump is connected to a host computer.

[0011] A measuring method of an oil well water content measuring device is specifically implemented according to the following steps:

[0012] Step 1: Cover the storage cylinder with a top cover and install it in the wellhead oil storage tank. The height direction of the storage cylinder is consistent with the height direction of the wellhead oil storage tank. The crude oil in the wellhead oil storage tank enters the storage cylinder through the liquid inlet groove on the side wall of the storage cylinder;

[0013] Step 2: The host computer controls the ultrasonic probe a to measure the liquid level of the storage tube. When the liquid level of the storage tube is not less than 20 cm, the host computer controls the air pump to inflate the sealing airbag. When the airbag is opened and the liquid inlet gap is completely closed, the inflation is stopped.

[0014] Step 3, the upper computer controls the heating layer to heat. When the heating time reaches 1 to 1.5 hours and the temperature detected by the temperature detector is higher than 80°C, the distance h2 from the top of the ultrasonic probe b to the oil-water interface is measured by the ultrasonic probe b. The height of the ultrasonic probe b is H2. The distance h between the top of the ultrasonic probe b and the bottom of the storage tube and the distance h1 between the top of the ultrasonic probe b and the oil surface are measured by the ultrasonic probe a.

[0015] Step 4: Calculate the water content of crude oil based on the distance h2 from the top of ultrasonic probe b to the oil-water interface obtained in step 3, the height of ultrasonic probe b is H2, the distance h between the top of ultrasonic probe b and the bottom of the storage cylinder, and the distance h1 from the top of ultrasonic probe b to the oil surface:

[0016] Liquid level in tank = h-h1

[0017] Oil-water interface height = h2 + H2

[0018]

[0019] The beneficial effects of the present invention are as follows: an oil well water content measuring device of the present invention has the characteristics of small sampling result error, accurate water content measurement result, safe and reliable equipment operation, and low investment, and provides a hardware foundation for realizing unmanned on-site oil well operation and perfecting oil well automation management, and has a simple structure and low cost; a measuring method of an oil well water content measuring device of the present invention has accurate measurement results and improves work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a storage cylinder in an oil well water content measuring device of the present invention;

[0021] Figure 2 This is a bottom view of a top cover in an oil well water content measuring device of the present invention;

[0022] Figure 3 It is a top view of a storage cylinder in an oil well water content measuring device of the present invention;

[0023] Figure 4 It is a principle diagram of an oil well water content measuring device of the present invention;

[0024] Figure 5 It is a schematic diagram of an inlet and outlet pipe in an oil well water content measuring device of the present invention;

[0025] Figure 6 It is a schematic diagram of the relationship between the emulsified water content and the water content of the Chang 6 crude oil in an oil well water content measuring device of the present invention;

[0026] Figure 7 The present invention is a schematic diagram of the relationship between the emulsified water content and the water content of the Zhongchang 2 crude oil in an oil well water content measuring device.

[0027] In the figure, 1. storage cylinder, 2. heating layer, 3. sealing airbag, 4. air inlet and exhaust pipes, 5. ultrasonic probe a, 6. top cover, 7. ultrasonic probe b, 8. temperature detector. DETAILED DESCRIPTION

[0028] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] The present invention provides an oil well water content measuring device, characterized in that it comprises a storage cylinder 1, the storage cylinder 1 can input and discharge crude oil in a wellhead oil storage tank, an ultrasonic probe b7 is arranged on the inner bottom surface of the storage cylinder 1, and a top cover 6 is arranged on the top of the storage cylinder 1. Figure 2 As shown, the inner top surface of the top cover 6 is provided with an ultrasonic probe a5, and the ultrasonic probe b7 and the ultrasonic probe a5 are both connected to a host computer. Figure 3 As shown, a liquid inlet groove is provided on the side wall of the storage tube 1, and the liquid inlet groove runs through the side wall of the storage tube 1 horizontally, and the liquid inlet groove is longitudinally from the opening of the storage tube 1 to the bottom of the storage tube 1. A sealing airbag 3 is provided on any side wall of the liquid inlet groove, and the sealing airbag 3 is connected to an air inlet and exhaust pipe 4, and the air inlet and exhaust pipe 4 is connected to an air pump, and the air pump is connected to a host computer. The storage tube 1 includes an inner tube and an outer tube, and a heating layer 2 is provided on the outer wall of the inner tube, and an insulating sealant is filled between the outer tube and the heating layer 2. The heating layer 2 is a silicone rubber heating sheet, and the silicone rubber heating sheet is connected to the host computer. A temperature detector 8 is provided on the inner bottom surface of the inner tube, and the temperature detector 8 is connected to the host, and the connection lines between the temperature detector 8, the ultrasonic probe b7, the ultrasonic probe a5, the silicone rubber heating sheet and the host computer are all located in the insulating sealant.

[0030] The present invention provides a method for measuring the water content of an oil well, which is specifically implemented according to the following steps:

[0031] Step 1, cover the storage cylinder 1 with a top cover 6 and install it in the wellhead oil storage tank. The height direction of the storage cylinder 1 is consistent with the height direction of the wellhead oil storage tank. The crude oil in the wellhead oil storage tank enters the storage cylinder 1 through the liquid inlet groove on the side wall of the storage cylinder 1;

[0032] Step 2: The host computer controls the ultrasonic probe a5 to measure the liquid level of the storage tube 1. When the liquid level of the storage tube 1 is not less than 20 cm, the host computer controls the air pump to inflate the sealing airbag 3. When the airbag is opened and the liquid inlet gap is completely closed, the inflation is stopped.

[0033] Step 3, the upper computer controls the heating layer 2 to heat. When the heating time reaches 1 to 1.5 hours and the temperature detected by the temperature detector 8 is higher than 80°C, the distance h2 from the top of the ultrasonic probe b7 to the oil-water interface is measured by the ultrasonic probe b7. The height of the ultrasonic probe b7 is H2. The distance h between the top of the ultrasonic probe b7 and the bottom of the storage tube 1 and the distance h1 between the top of the ultrasonic probe b7 and the oil surface are measured by the ultrasonic probe a5.

[0034] Step 4: Calculate the water content of crude oil based on the distance h2 from the top of ultrasonic probe b7 to the oil-water interface obtained in step 3, the height of ultrasonic probe b7 is H2, the distance h between the top of ultrasonic probe b7 and the bottom of storage cylinder 1, and the distance h1 from the top of ultrasonic probe b7 to the oil surface:

[0035] Liquid level in tank = h-h1

[0036] Oil-water interface height = h2 + H2

[0037]

[0038] The present invention provides an oil well water content measuring device, such as Figure 4 As shown, Figure 4 The test terminals are the storage cylinder 1 and the top cover 6, and the server is the host computer. The staff can monitor and control various data of the storage cylinder 1 through the host computer, thereby increasing work efficiency.

[0039] The present invention provides an oil well water content measuring device, such as Figure 5 As shown, Figure 5In the figure, A represents the air pump suction port, B represents air, D represents the sealed airbag 3, and C represents the air pump exhaust port. When inflating, the electromagnetic valve between the air pump suction port and the air, and the electromagnetic valve between the air pump exhaust port and the sealed airbag 3 are opened by the host computer, and the electromagnetic valve between the air pump suction port and the sealed airbag 3, and the electromagnetic valve between the air pump exhaust port and the air are closed. At this time, the air pump extracts air and inputs it into the sealed airbag 3 to inflate the sealed airbag 3. When exhausting, the electromagnetic valve between the air pump exhaust port and the air, and the electromagnetic valve between the air pump suction port and the sealed airbag 3 are opened by the host computer, and the electromagnetic valve between the air pump suction port and the air, and the electromagnetic valve between the air pump exhaust port and the sealed airbag 3 are closed. At this time, the air pump extracts gas from the sealed airbag 3 and outputs it to the air to complete the exhaust. The sealed airbag is the same length as the liquid inlet tank and is made of a long strip of oil-resistant material. When it is necessary to measure the moisture content, start the air pump to inflate the sealed airbag, and the airbag opens to completely close the liquid inlet. After the measurement is completed, start the air pump to evacuate the airbag and open the liquid inlet slot.

[0040] The invention discloses an oil well water content measuring device, which performs longitudinal full-section sampling in an oil storage tank at the wellhead of the oil well, and the sampling result is accurate; the oil sample is heated to above 80°C, the emulsified water content is lower than 1.5%, and then the height of the oil-water interface is measured, so as to obtain the comprehensive water content of the crude oil of the well.

[0041] After the crude oil is heated, some emulsified water remains in it. Figure 6 and Figure 7 It is the change curve of emulsified water content after heating the oil samples from two oil fields. It can be seen that when the oil sample is heated to above 80℃, the emulsified water content is lower than 1.5%, and no longer decreases significantly with the increase of temperature. This value is a constant a at the same temperature in the oil samples of the same oil field; therefore, it is determined that the measurement can be carried out when the heating temperature of the oil sample reaches above 80℃; after adding a correction to the measurement result, it can be determined as the final water content of the well.

[0042] The present invention discloses an oil well water content measuring device, which adopts a silicone rubber heating sheet. The heating method is that the silicone rubber heating sheet is closely attached to the outer wall of a stainless steel inner cylinder, so that heat can be quickly transferred to a sample. A temperature controller is installed on the heating sheet to ensure that the working temperature of the heating sheet is not higher than 85°C. The flameproof insulating sealant also has a heat conduction function. When the temperature of the inner cylinder is too high, the heat conduction function of the insulating sealant can transfer the heat to the outer cylinder, so as to ensure that the temperature of the inner cylinder will not be too high, thereby playing a secondary protection role. The silicone rubber heating sheet is mainly composed of alloy heating wire and silicone rubber high-temperature insulating cloth. It has fast heating, uniform temperature, high thermal efficiency, good toughness, pressure resistance, and friction resistance. It is easy to use, safe, and waterproof. The insulation material has a maximum temperature resistance of 250°C and a maximum use temperature of 200°C, which can fully meet the use conditions. To further ensure safety, after the silicone rubber heating sheet is pasted on the outer wall of the inner tube, insulating sealant is poured between the inner and outer tubes to prevent leakage after aging of the insulating cloth. The temperature detector 8 uses the TP100 probe, the ultrasonic probe a5 is model HM-UL1.5M41A, and the ultrasonic probe b7 is model HM-UL03M41A.

[0043] The present invention provides an oil well water content measuring device. A liquid inlet groove is opened on the side wall of a storage cylinder 1. The output liquid in the oil storage tank enters the inner cylinder in the same proportion, ensuring that the oil sample in the cylinder and the output liquid in the oil storage tank are completely consistent.

[0044] The present invention discloses an oil well water content measuring device, which has the characteristics of small sampling result error, accurate water content measurement result, safe and reliable equipment operation and low investment, and provides a hardware foundation for realizing unattended oil well site and perfecting oil well automation management, and has a simple structure and low cost. The present invention discloses a measuring method for an oil well water content measuring device, which has accurate measurement results and improves work efficiency.

Claims

1. An oil well water content measuring device, characterized in that , comprising a storage cylinder (1), the storage cylinder (1) being capable of inputting and discharging crude oil in a wellhead oil storage tank, the inner bottom surface of the storage cylinder (1) being provided with an ultrasonic probe b (7), the top of the storage cylinder (1) being provided with a top cover (6), the inner top surface of the top cover (6) being provided with an ultrasonic probe a (5), the ultrasonic probe b (7) and the ultrasonic probe a (5) being both connected to a host computer; The storage cylinder (1) comprises an inner cylinder and an outer cylinder, a heating layer (2) is provided on the outer side wall of the inner cylinder, and an insulating sealant is filled between the outer cylinder and the heating layer (2); The heating layer (2) is a silicone rubber heating sheet, and the silicone rubber heating sheet is connected to a host computer; The inner bottom surface of the inner cylinder is provided with a temperature detector (8), the temperature detector (8) is connected to a host computer, and the connection wires between the temperature detector (8), the ultrasonic probe b (7), the ultrasonic probe a (5), the silicone rubber heating sheet and the host computer are all located in the insulating sealant; A liquid inlet groove is provided on the side wall of the storage cylinder (1), the liquid inlet groove runs through the side wall of the storage cylinder (1) in the transverse direction, and the liquid inlet groove extends longitudinally from the opening of the storage cylinder (1) to the bottom of the storage cylinder (1), and a sealing airbag (3) is provided on any side wall of the liquid inlet groove, the sealing airbag (3) is connected to an air inlet and exhaust pipe (4), the air inlet and exhaust pipe (4) is connected to an air pump, and the air pump is connected to a host computer.

2. The measuring method of the oil well water content measuring device according to claim 1 is characterized in that: Follow the steps below to implement: Step 1: Cover the storage cylinder (1) with a top cover (6) and install it in a wellhead oil storage tank. The height direction of the storage cylinder (1) is consistent with the height direction of the wellhead oil storage tank. The crude oil in the wellhead oil storage tank enters the storage cylinder (1) through the liquid inlet groove on the side wall of the storage cylinder (1); Step 2: The host computer controls the ultrasonic probe a (5) to measure the liquid level of the storage tube (1). When the liquid level of the storage tube (1) is not less than 20 cm, the host computer controls the air pump to inflate the sealing airbag (3). When the airbag is opened and the liquid inlet gap is completely closed, the inflation is stopped. Step 3, the upper computer controls the heating layer (2) to heat. When the heating time reaches 1 to 1.5 hours and the temperature detected by the temperature detector (8) is higher than 80° C., the distance h2 from the top of the ultrasonic probe b (7) to the oil-water interface is measured by the ultrasonic probe b (7), where the height of the ultrasonic probe b (7) is H2. The distance h between the top of the ultrasonic probe a (5) and the bottom of the storage tube (1) and the distance h1 between the top of the ultrasonic probe a (5) and the oil surface are measured by the ultrasonic probe a (5). Step 4: Calculate the water content of crude oil based on the distance h2 from the top of ultrasonic probe b (7) to the oil-water interface obtained in step 3, the height of ultrasonic probe b (7) H2, the distance h between the top of ultrasonic probe a (5) and the bottom of storage cylinder (1), and the distance h1 between the top of ultrasonic probe a (5) and the oil surface: Liquid level in tank = h-h1 Oil-water interface height = h2 + H2 Moisture content = (h2+H2) / (h-h1).

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