High-pressure small-flow gas distribution device and method

Abstract

The invention discloses a high-pressure small-flow gas distribution device and method, and belongs to the field of yield increasing and transforming processes and matched technologies. The high-pressure small-flow gas distribution device comprises a high-pressure gas distributor, a gas inlet pipeline is connected to the inlet end of the high-pressure gas distributor, and a plurality of gas injection branches are connected to the outlet end of the high-pressure gas distributor; a volumetric flowmeter, a single-well pressure control valve and a single-well high-pressure gate valve are sequentially arranged on the gas injection branch; the air inlet pipeline is connected with the compressor. The high-pressure gas distributor injects gas into a plurality of gas injection branches at the same time, a single-well high-pressure gate valve is arranged in a matched mode, it is guaranteed that the difference between the inlet pressure and the outlet pressure is constant, a volumetric flow meter is adopted for metering, constant output is achieved under a certain pressure difference, the injection amount of each well is also guaranteed, continuous metering per second is changed into continuous multi-second metering, and the metering efficiency is greatly improved. And in a period of time, continuous injection and metering accuracy are realized. The low-flow pressure of multiple wells under high pressure can be achieved, the flow is stable, accurate injection amount and continuous injection are guaranteed, and the gas injection requirements of natural gas drive, air drive and the like are met.

Description

Technical Field

[0001] The invention belongs to the field of production increase and transformation technology and supporting technology, and specifically relates to a high-pressure and small-flow gas distribution device and method. Background Art

[0002] At present, most water-driven oil reservoirs have entered the middle and late stages of development. The water content of the oil fields is high and the degree of water drive control is low. Tertiary oil recovery technology needs to be developed to improve the recovery rate of crude oil. Through practical experiments, gas drive has unique advantages that water drive does not have. Natural gas drive uses injected natural gas and crude oil to mix. Among them, the recovery rate of miscible drive is 20-60%, and the recovery rate of immiscible drive is 8-13%. Air drive can inject air into the reservoir to: ① increase or maintain the reservoir pressure and quickly replenish the reservoir energy; ② the air injected into the reservoir reacts with the crude oil at a low temperature to indirectly achieve CO 2 The CO generated 2 It dissolves in crude oil under reservoir pressure, reduces crude oil viscosity and improves crude oil recovery; ③ The thermal effect produced by low-temperature oxidation reaction can further reduce crude oil viscosity, increase crude oil fluidity, and improve oil recovery efficiency. At the same time, gas drive has the advantages of small injection pressure difference, relatively simple gas treatment process, no damage to oil layer, no corrosion to pipeline, recyclable, and low operating cost.

[0003] The method of gas drive injection is to compress natural gas / air through a compressor, form high-pressure gas and distribute it to each gas injection well through a gas distribution device, so that each well can meet the designed gas injection volume. The first technical problem is that the gas injection volume of a single well is small, 3000~5000Nm under standard conditions. 3 / d, calculated based on the injection pressure of 20 MPa per well, the gas injection flow rate is 2×10 -4 ~3×10 -4 m 3 / s, which requires the flow meter to be extremely accurate. Through research, it is found that there are no such high-pressure and high-precision flow meters at home and abroad. The second technical problem is that the injection pressure of each well is different during the gas injection process. The pressure difference between the gas supply pressure and the injection pressure is different for each well. When the gas distribution device distributes gas to each well, the gas injection volume of the injection well with a large pressure difference is difficult to be consistent with the gas injection volume of the injection well with a small pressure difference. Some gas injection wells have over-injection and some gas injection wells have under-injection. The injection pressure is difficult to adjust, and thus the gas injection volume and pressure of "even well distribution" cannot be met.

[0004] As an effective technology to improve oil recovery, gas drive has been used in many tests and has achieved good development results. At present, the most commonly used technical solution for gas drive to deal with the problems of high-pressure small flow metering and uneven "well distribution" is the "multi-well rotation injection" method, that is, the time cycle is calculated according to the displacement of the compressor, and the gas injection volume of the first well is satisfied before the next well is rotated, and the cycle continues in sequence. However, there is a problem that it is impossible to inject multiple wells at the same time. Summary of the invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a high-pressure, low-flow gas distribution device and method to solve the problems of high-pressure, low-flow metering and uneven "well distribution" in the prior art, and the technical problem of being unable to achieve simultaneous injection into multiple wells.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A high-pressure, low-flow gas distribution device comprises: a high-pressure gas distributor, wherein the inlet end of the high-pressure gas distributor is connected to a gas pipeline, and the outlet end is respectively connected to a plurality of gas injection branches, wherein the gas injection branches are sequentially provided with a volumetric flowmeter, a single-well pressure control valve and a single-well high-pressure gate valve; the gas pipeline is connected to a compressor.

[0008] Preferably, a high-pressure filter is provided before the volumetric flowmeter on the gas injection branch.

[0009] Preferably, the pressure at the high-pressure gate valve of a single well on the gas injection branch is 0.2-0.5 MPa higher than the maximum injection pressure of the single well.

[0010] Preferably, the incoming gas pipeline is also provided with a high-pressure gate valve for controlling the on and off of the incoming gas.

[0011] Preferably, the high-pressure gas distributor is also connected to an incoming gas pressure gauge and an incoming gas temperature gauge.

[0012] Preferably, the outlet end of the high-pressure gas distributor is connected to a plurality of gas injection branches, and a plurality of high-pressure ball valves for controlling the on-off of gas injection in the branches are respectively provided.

[0013] Preferably, a gas injection line vent valve is also provided between the volumetric flow meter and the single well pressure control valve.

[0014] Preferably, a single-well gas injection pressure gauge is further provided between the single-well pressure control valve and the single-well high-pressure gate valve, and the single-well pressure control valve and the single-well gas injection pressure gauge are also connected to a pressure monitor and a pressure transmitter.

[0015] The present invention also discloses a high-pressure and low-flow gas distribution method, comprising the following steps:

[0016] Determine the starting pressure of the single well pressure control valve according to the highest injection pressure of several steam injection wells managed by the gas distribution device;

[0017] High-pressure gas enters the high-pressure gas distributor from the gas pipeline, and then enters several gas injection branches through the high-pressure gas distributor;

[0018] The high-pressure gas in the gas injection branch reaches the wellhead of each gas injection well through the volumetric flow meter, the single-well pressure control valve and the single-well high-pressure gate valve;

[0019] Each gas injection well adjusts the high-pressure gas of the gas injection branch to the corresponding wellhead gas injection pressure for gas injection.

[0020] Preferably, the gas injection pressure of the high-pressure gas distributor entering the gas injection branch is greater than the start-up pressure of the single-well pressure control valve.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] A high-pressure, low-flow gas distribution device disclosed in the present invention adopts a high-pressure gas distributor to inject gas into several gas injection branches at the same time, and is equipped with a single-well high-pressure gate valve to ensure that the difference between the inlet pressure and the outlet pressure is a constant pressure. A volumetric flowmeter is used for measurement. Under a certain pressure difference, the constant output of the volumetric flow is guaranteed, and the injection amount of each well is also ensured. This method changes the continuous per-second measurement into continuous multi-second measurement, and also realizes continuous injection and metering accuracy within a day. Using the idea of ​​zero-to-integral and equal pressure difference, zero-to-integral is to use a volumetric flowmeter to change the original measurement in seconds to minutes, so as to achieve accumulation of small amounts, thereby ensuring the accuracy of gas volume under one measurement unit; equal pressure difference is to count the injection pressure of the gas injection wells under the jurisdiction of the compressor, and take the highest injection pressure as the injection pressure of the gas injection well. The equal pressure difference means that the pressure difference between the gas supply pressure and the highest injection pressure is constant, that is, the highest injection pressure is taken as the set pressure, and the injection pressure is greater than the highest injection pressure. A gas distribution device is designed, and the pressure at the outlet of the gas distribution device is the injection pressure of each well (taking the highest pressure in the gas injection wells under its jurisdiction), so as to ensure the consistency of the injection pressure. "One-to-many" is achieved, that is, one compressor can realize the injection of multiple wells, and at the same time, the pressure and flow of multiple wells at low flow under high pressure can be stable, ensuring accurate and continuous injection, and meeting the gas injection requirements of natural gas drive and air drive.

[0023] The present application firstly ensures the continuity of gas injection volume, solves the problem of rotation injection of multiple gas injection wells, and can use large-displacement compressors to meet the gas injection of multiple wells, thereby reducing the number of compressors; secondly, realizes accurate measurement of gas injection volume, and does not need to rely solely on the displacement of the compressor to calculate the gas volume of the rotation injection wells; thirdly, provides strong technical support for the large-scale development of gas drives such as natural gas drive, air foam drive, and carbon dioxide drive in tertiary oil recovery.

[0024] The invention improves the stability and accuracy of gas injection in gas drive, solves the problem of rotation injection in multiple wells, and reduces the labor intensity of personnel switching valves on site. According to the calculation of rotation injection of one compressor in four wells, there are 24 gas injection wells under its jurisdiction, so at least six compressors are needed. If a gas distribution valve group is used for gas injection, only one large-displacement compressor is needed, and then multi-well gas injection is carried out through one gas injection trunk line, which can reduce the cost by about 3 million yuan (one compressor is calculated at 500,000 yuan, and the gas injection pipeline is converted); with the increase in the scale of gas drive development, the number of gas injection wells gradually increases. According to the estimate of 240 wells, the cumulative direct cost in the next 3-5 years will be about 30 million yuan. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the device structure of an embodiment of the present invention.

[0026] Among them: 1-incoming gas pipeline; 2-high-pressure gate valve; 3-high-pressure gas distributor; 4-incoming gas pressure gauge; 5-incoming gas temperature gauge; 6-high-pressure ball valve; 7-high-pressure filter; 8-volumetric flowmeter; 9-single well pressure control valve; 10-single well gas injection pressure gauge; 11-single well high-pressure gate valve; 12-gas injection well; 13-gas injection pipeline vent valve. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0030] The present invention utilizes the ideas of rounding off and equal pressure difference. Rounding off means using a volumetric flow meter to change the original measurement in seconds into calculation in minutes, thereby accumulating small amounts into large amounts, thereby ensuring the accuracy of the gas volume under one measurement unit; equal pressure difference means statistically analyzing the injection pressures of the gas injection wells under the jurisdiction of the compressor, with the highest injection pressure being the injection pressure of the gas injection wells. Equal pressure difference means that the pressure difference between the gas supply pressure and the highest injection pressure is constant, that is, with the highest injection pressure as the set pressure, the gas injection pressure is greater than the highest injection pressure, and a gas distribution device is designed, the pressure at the outlet of the gas distribution device is the injection pressure of each well (taking the highest pressure in the gas injection wells under its jurisdiction), thereby ensuring consistent injection pressure.

[0031] The purpose of the present invention is to provide a high-pressure, low-flow gas distribution device to achieve "one-to-many", that is, one compressor can realize the injection of multiple wells, and at the same time, it can achieve the stability of pressure and flow of multiple wells at low flow under high pressure, ensure accurate and continuous injection, and meet the gas injection requirements of natural gas drive, air drive, etc. The present invention specifically achieves the above purpose through the following technical solutions:

[0032] A high-pressure, low-flow gas distribution device includes: a high-pressure gas distributor 3, the inlet end of the high-pressure gas distributor 3 is connected to a gas pipeline 1, and the outlet end is respectively connected to a plurality of gas injection branches, and the gas injection branches are sequentially provided with a volumetric flowmeter 8, a single-well pressure control valve 9 and a single-well high-pressure gate valve 11; the gas pipeline 1 is connected to a compressor. The high-pressure gas distributor 3 is used to inject gas into a plurality of gas injection branches at the same time, and the single-well high-pressure gate valve 11 is provided in cooperation to ensure that the difference between the inlet pressure and the outlet pressure is a constant pressure, and the volumetric flowmeter 8 is used for metering. Under a certain pressure difference, the constant output of the volumetric flow is ensured, and the injection amount of each well is also ensured. This method changes the continuous per-second metering to the continuous multi-second metering, and also achieves continuous injection and metering accuracy within a day.

[0033] In some embodiments, a high-pressure filter 7 is also provided in front of the volumetric flowmeter 8 on the gas injection branch; due to the small amount of injected gas, the valve control accuracy is very high, and a small amount of impurities in the gas injection pipeline and the injected gas seriously affect the control degree of the valve, resulting in inaccurate metering or even inability to measure. A set of filters is added in front of the flowmeter. The high-pressure filter 7 must first ensure the filtration of impurities, and secondly prevent the filtered impurities from rolling up under the influence of high-pressure gas, causing valve control failure and flowmeter blockage. Considering the timely cleaning of impurities, a back-purge control device is provided on the filter, and back-purge cleaning is performed in time after the filter pressure difference alarm.

[0034] In some embodiments, the pressure at the single-well high-pressure gate valve 11 on the gas injection branch is 0.2 to 0.5 MPa higher than the maximum injection pressure of the single well, which is conducive to achieving consistent pressure for each injection well by the gas distribution device and ensuring that the pressure meets the injection pressure of each well.

[0035] In some embodiments, the incoming gas pipeline 1 is also provided with a high-pressure gate valve 2 for controlling the on-off of the incoming gas.

[0036] In some embodiments, the high-pressure gas distributor 3 is also connected to an incoming gas pressure gauge 4 and an incoming gas temperature gauge 5 for displaying the incoming gas pressure and the incoming gas temperature respectively.

[0037] In some embodiments, the outlet end of the high-pressure gas distributor 3 is connected to a plurality of gas injection branches, and a plurality of high-pressure ball valves 6 for controlling the on-off of gas injection in the branches are respectively provided thereon.

[0038] In some embodiments, a gas injection pipeline vent valve 13 is further provided between the volumetric flow meter 8 and the single well pressure control valve 9 .

[0039] In some embodiments, a single-well gas injection pressure gauge 10 is also provided between the single-well pressure control valve 9 and the single-well high-pressure gate valve 11, and the single-well pressure control valve 9 and the single-well gas injection pressure gauge 10 are also connected to a pressure monitor and a pressure transmitter.

[0040] The utility model relates to a high-pressure and small-flow gas distribution device, which is mainly composed of a metering system, a pressure control and a filtering part.

[0041] (1) Metering part: The single well pressure control valve 9 first achieves the consistency of the outlet pressure and is set slightly higher than the maximum injection pressure; the pressure regulating valve mainly adjusts the pressure before and after the flow meter to maintain a constant pressure difference. When a set of metering is completed, the pressure control valve opens according to the set pressure to achieve normal gas injection.

[0042] (2) Pressure control part: The pressure before and after the volumetric flowmeter 8 is linked with the pressure regulating valve. The constant pressure of the volumetric flowmeter 8 is adjusted in real time according to the incoming gas pressure to ensure that the pressure is constant and the flow is constant; the pressure difference before and after the filter is monitored mainly for timely back-purge. Filter blockage can easily cause inaccurate metering. Adding a back-purge function is to ensure the smooth operation of the flowmeter; the incoming gas pressure of the compressor is linked with the outlet pressure of the device. The constant pressure difference between the incoming gas pressure and the outlet pressure is adjusted in real time to achieve stable injection of multiple wells by one compressor.

[0043] (3) Filtering part: Due to the small amount of injected gas, the valve control accuracy is very high. The small amount of impurities in the gas injection pipeline and the injected gas seriously affect the control degree of the valve, resulting in inaccurate metering or even inability to measure. A set of high-pressure filters 7 is added in front of the flow meter. The high-pressure filter 7 must first ensure the filtration of impurities, and secondly prevent the filtered impurities from rolling up under the influence of high-pressure gas, causing valve control failure and flow meter blockage. Considering the timely cleaning of impurities, a back-purge control device is set on the high-pressure filter 7. When the pressure difference alarm of the high-pressure filter 7 is triggered, the back-purge cleaning is carried out in time.

[0044] The present invention also discloses a high-pressure and low-flow gas distribution method, comprising the following steps:

[0045] S1: Determine the starting pressure of the single well pressure control valve 9 according to the highest injection pressure of several steam injection wells managed by the gas distribution device;

[0046] S2: High-pressure gas enters the high-pressure gas distributor 3 from the gas pipeline 1, and enters several gas injection branches through the high-pressure gas distributor 3;

[0047] S3: The high-pressure gas in the gas injection branch reaches the wellhead of each gas injection well through the volumetric flow meter 8, the single-well pressure control valve 9 and the single-well high-pressure gate valve 11;

[0048] S4: Each gas injection well adjusts the high-pressure gas of the gas injection branch to the corresponding wellhead gas injection pressure for gas injection.

[0049] In some embodiments, the gas injection pressure of the high-pressure gas distributor 3 entering the gas injection branch is greater than the start-up pressure of the single-well pressure control valve 9 .

[0050] The core technologies of this method mainly include three aspects:

[0051] (1) Adjust the injection pressure of multiple wells under the control of the gas distribution device to a uniform injection pressure, which is slightly higher than the injection pressure of the highest well (about 0.2-0.5MPa higher), so as to achieve the consistency of the pressure of each injection well by the gas distribution device and ensure that the pressure meets the injection pressure of each well. The main purpose of adjusting to a uniform pressure is to achieve a constant pressure difference between the inlet pressure and the outlet pressure, prevent pressure deviation, and provide a stable pressure difference for flow measurement.

[0052] (2) A volumetric flow meter 8 is used for measurement. Under a certain pressure difference, the constant output of the volumetric flow is guaranteed, and the injection volume of each well is also ensured. This method changes the continuous per-second measurement to continuous multi-second measurement, and also achieves continuous injection and measurement accuracy within a day.

[0053] (3) The injection pressure is linked to the compressor operating pressure. During the continuous gas injection process, the injection pressure will change. Through linkage, a certain pressure difference is maintained with the compressor operating pressure, thus forming a stable injection pressure and gas injection volume.

[0054] Application of gas distribution device

[0055] According to the number of gas injection wells, it is mainly divided into three-well type, four-well type and multi-well type gas distribution devices.

[0056] (1) Valves, filters, flow meters, pressure regulating valves, pressure control valves, and pressure control devices are integrated on a skid, making them easy to move and manage.

[0057] (2) The pressure setting of the pressure control valve is determined based on the maximum pressure of the injection well under its jurisdiction. The gas injection volume is determined according to geological requirements and then volumetric calculation is performed to set a reasonable volume.

[0058] (3) During field application, the injection wells should be classified in advance according to their pressures, and those with smaller pressure differences should be grouped together, which is beneficial for pressure adjustment and energy consumption reduction.

[0059] (4) A pressure control system is installed on each injection pipeline to adjust the pressure linkage and pressure difference to be constant.

[0060] [Example]

[0061] like Figure 1 As shown, the structure of the present invention mainly consists of a gas pipeline 1, a high-pressure gate valve 2, a high-pressure gas distributor 3, a gas pressure gauge 4, a gas temperature gauge 5, a high-pressure ball valve 6, a high-pressure filter 7, a positive displacement flowmeter 8, a single-well pressure control valve 9, a single-well gas injection pressure gauge 10, a single-well high-pressure gate valve 11, a gas injection well 12, a gas injection pipeline vent valve 13, etc.

[0062] Take the three-well type as an example: Assuming that the highest injection pressure of the three wells under the jurisdiction of the gas distribution device is A, the starting pressure of the single-well pressure control valve 9 is set to (A+0.2)MPa; that is: the gas injection pressure of the three wells is unified to (A+0.2)MPa; it has nothing to do with the pressure value of the actual gas injection well, and there is a possibility that the actual gas injection pressure is very different from the pressure controlled by the device. When the high-pressure gas of the compressor passes through the incoming gas pipeline 1 to the gas distribution device, the high-pressure gate valve 2 is opened to enter the high-pressure gas distributor 3 in the gas distribution device, and the high-pressure gas distributor 3 displays the incoming gas pressure and temperature through the incoming gas pressure gauge 4 and the incoming gas temperature gauge 5. Set the incoming gas pressure to B, which is higher than the starting pressure of the single-well pressure control valve 9 by 0.5MPa (this value can be adjusted), that is, B-(A+0.2)=0.5MPa; in this way, the pressure difference is constant at 0.5MPa. Under the condition of constant pressure difference, the metering accuracy of the flowmeter is greatly improved. By using a volumetric flow meter, the pressure difference is constant and the quantitative gas is easy to control, so that the amount of gas injected into the three wells can be equal, thereby ensuring that the "well distribution" is even. It also avoids the phenomenon that the low-pressure well is easy to take in gas while the high-pressure well cannot take in gas due to the different gas injection pressures of the three wells.

[0063] The present invention has the following characteristics due to the above design:

[0064] 1. When the injection pressure of each single well in the gas injection area is very different, uneven distribution of gas injection volume is likely to occur. The constant pressure difference principle is used to achieve uniform gas injection volume and stability of gas injection volume during gas drive oil production.

[0065] 2. This device uses the principle of accumulating small amounts to make a large amount, converting small units that cannot be measured into large units of actual measurement, and achieves the accuracy of gas injection volume within a large time range.

[0066] 3. The device has a simple structure and is easy to install. It can be used for oil recovery by other gas drives such as air foam drive, natural gas drive, and carbon dioxide drive. It is widely used and has good on-site applicability.

[0067] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A high-pressure and low-flow gas distribution device, It is characterized in that include: A high-pressure gas distributor (3), wherein the inlet end of the high-pressure gas distributor (3) is connected to a gas pipeline (1), and the outlet end is respectively connected to a plurality of gas injection branches, wherein the gas injection branches are sequentially provided with a volumetric flow meter (8), a single-well pressure control valve (9) and a single-well high-pressure gate valve (11); the gas pipeline (1) is connected to a compressor.

2. A high-pressure and low-flow gas distribution device according to claim 1, It is characterized in that A high-pressure filter (7) is also provided before the volumetric flow meter (8) on the gas injection branch line.

3. A high-pressure and low-flow gas distribution device according to claim 1, It is characterized in that The pressure at the single-well high-pressure gate valve (11) on the gas injection branch line is 0.2-0.5 MPa higher than the maximum injection pressure of the single well.

4. A high-pressure and low-flow gas distribution device according to claim 1, It is characterized in that The incoming gas pipeline (1) is also provided with a high-pressure gate valve (2) for controlling the on and off of the incoming gas.

5. A high-pressure and low-flow gas distribution device according to claim 1, It is characterized in that The high-pressure gas distributor (3) is also connected to an incoming gas pressure gauge (4) and an incoming gas temperature gauge (5).

6. A high-pressure and low-flow gas distribution device according to claim 1, It is characterized in that The outlet end of the high-pressure gas distributor (3) is connected to a plurality of gas injection branches, and a plurality of high-pressure ball valves (6) for controlling the on and off of gas injection in the branches are respectively provided.

7. A high-pressure and low-flow gas distribution device according to claim 1, It is characterized in that A gas injection pipeline vent valve (13) is also provided between the volumetric flow meter (8) and the single well pressure control valve (9).

8. A high-pressure and low-flow gas distribution device according to claim 1, It is characterized in that A single-well gas injection pressure gauge (10) is also provided between the single-well pressure control valve (9) and the single-well high-pressure gate valve (11), and the single-well pressure control valve (9) and the single-well gas injection pressure gauge (10) are also connected to a pressure monitor and a pressure transmitter.

9. A high-pressure and low-flow gas distribution method based on the high-pressure and low-flow gas distribution device according to any one of claims 1 to 8, It is characterized in that The following steps are involved: Determining the starting pressure of the single well pressure control valve (9) according to the highest injection pressure of a number of steam injection wells managed by the gas distribution device; High-pressure gas enters the high-pressure gas distributor (3) from the gas pipeline (1), and enters a plurality of gas injection branches through the high-pressure gas distributor (3); The high-pressure gas in the gas injection branch reaches the wellhead of each gas injection well through a volumetric flow meter (8), a single-well pressure control valve (9) and a single-well high-pressure gate valve (11); Each gas injection well adjusts the high-pressure gas of the gas injection branch to the corresponding wellhead gas injection pressure for gas injection.

10. A high-pressure and low-flow gas distribution method according to claim 9, It is characterized in that The gas injection pressure of the high-pressure gas distributor (3) entering the gas injection branch is greater than the starting pressure of the single well pressure control valve (9).

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