Dosing system and method thereof

Abstract

The present invention discloses a drug dosing system and method thereof, wherein the drug dosing system comprises a container, a pump inlet pipe, a high-pressure pump, a pump outlet tee, a reflux pipe fitting, a reflux regulating valve, a reflux pipe, a drug delivery pipe, a drug distribution tee, a first drug dosing pipe, a first regulating valve, a first metering pipe fitting, a first high-pressure micro-flowmeter, a first drug distribution pipe, a second drug dosing pipe, a second regulating valve, a second metering pipe fitting, and a second high-pressure micro-flowmeter; the lower part of the container is connected to one end of the pump inlet pipe, and the other end of the pump inlet pipe is connected to the inlet of the high-pressure pump; the high-pressure pump outlet is connected to one end of the pump outlet tee; the side interface of the pump outlet tee is connected to the inlet of the reflux regulating valve by a reflux pipe fitting, and the other end of the pump outlet tee is connected to one end of the drug delivery pipe; the present invention can effectively solve the metering, adjustment, and control problems of drug dosing in oil and gas wells and pipelines, can save energy and reduce consumption, and meet production requirements; and has the advantages of easy implementation, safety and reliability, wide application, and easy promotion.

Description

Technical Field

[0001] The present invention relates to the field of drug addition in oil wells, gas wells and pipelines, and in particular to a drug addition system and method thereof, which can be applied to oil wells, gas wells and gas pipelines that require the addition of drugs. Background Art

[0002] In order to reduce floor space or facilitate construction management, domestic oil and gas wells often adopt a cluster well layout, that is, two or more oil and gas wells are drilled in the same well site, and the distance between adjacent oil and gas trees is generally no more than 50 meters.

[0003] In order to ensure the normal production operation of such oil and gas wells, it is usually necessary to add functional chemicals (collectively referred to as agents) that are liquid at normal temperature and pressure into multiple oil and gas wells at the same time.

[0004] Take the shale gas wells in Weiyuan, Sichuan as an example.

[0005] The gas field is located in a mountainous and hilly area where land is scarce and the construction costs of roads and well sites are high. Therefore, 6 to 10 gas wells are usually drilled in the same well site, and the distance between the gas trees of two adjacent gas wells is generally no more than 20 meters.

[0006] Each gas well in the gas field needs to continuously add foaming agent into the oil casing annulus to drain water and produce gas, and generally it is necessary to continuously add defoaming agent into the surface pipeline (also known as gas production pipeline, gas gathering pipeline) at the outlet of each gas well to remove foam and separate gas and liquid (referred to as liquid separation).

[0007] See attached Figure 1 As shown, at present, each well in the gas field uses a separate metering pump to inject foaming agent, and the process can be summarized as follows: the foaming agent in the foaming agent tank 100 passes through the pump inlet pipe 101, the metering pump 102, the valve 103, and the pump outlet pipeline 104, continuously enters the oil and casing annulus of the gas well 105, and then flows to the bottom of the gas well 105; the foaming agent in the foaming agent tank 100 passes through the pump inlet pipe 106, the metering pump 107, the valve 108, and the pump outlet pipeline 109, and continuously enters the oil and casing annulus of the gas well 110 and then flows to the bottom of the gas well 110; the foaming agent in the foaming agent tank 100 passes through the pump inlet pipe 111, the metering pump 112, the valve 113, and the pump outlet pipeline 114, and continuously enters the oil and casing annulus of the gas well 115 and then flows to the bottom of the gas well 115.

[0008] See attached Figure 2As shown, similarly, at present, the surface pipeline of each well in the gas field uses a separate metering pump to add defoaming agent. The process can be summarized as follows: the defoaming agent in the defoaming agent tank 200 passes through the pump inlet pipe 201, the metering pump 202, the valve 203, and the pump outlet pipeline 204, and continuously enters the surface pipeline 205 at the outlet of the gas well 105; the defoaming agent in the defoaming agent tank 200 passes through the pump inlet pipe 206, the metering pump 207, the valve 208, and the pump outlet pipeline 209, and continuously enters the surface pipeline 210 at the outlet of the gas well 110; the defoaming agent in the defoaming agent tank 200 passes through the pump inlet pipe 211, the metering pump 212, the valve 213, and the pump outlet pipeline 214, and continuously enters the surface pipeline 215 at the outlet of the gas well 115.

[0009] This method has the following defects:

[0010] 1. This method cannot accurately measure, control or adjust the dosing flow rate, which often leads to insufficient or uneven dosing flow rate, thereby affecting gas well production.

[0011] Common knowledge in the art indicates that insufficient or uneven flow of defoaming agents added to gas wells can lead to unstable water and gas production, seriously impacting stable production. Insufficient or uneven flow of defoaming agents added to the surface pipeline at the gas well outlet can cause difficulty separating liquids in the gas-liquid separator, and in severe cases, can cause water hammer failures and damage to the natural gas compressor behind the separator. The amount of defoaming agents added to gas wells is generally 2 to 10 liters / day of stock solution or 10 to 50 liters / day of diluted solution (i.e., the stock solution is diluted 5 times and added). Based on 10 to 50 liters / day of diluted solution, the equivalent dosing flow rate of the diluted solution is 0.42 to 2.08 liters / hour. Therefore, gas well production requires precise metering, control, or adjustment of the dosing flow rate.

[0012] Common knowledge in the field indicates that there is currently no publicly available information or successful precedent for using flow meters to measure dosing flow when using metering pumps in China. A metering pump utilizes a cam mechanism to control the stroke of the plunger (or diaphragm) to control the percentage of the metering pump's rated displacement (or theoretical displacement), thereby achieving control over the metering pump's displacement. For example, if a metering pump has a rated displacement of 60 liters per hour, controlling the plunger's stroke at 50% of its maximum stroke using the cam mechanism would adjust the pump's displacement to 50% of the rated displacement, thereby adjusting the pump's displacement to 30 liters per hour.

[0013] It is common knowledge in the field that the valve of the metering pump (such as the ball valve seat of the outlet valve) will inevitably suffer severe wear due to continuous reciprocating motion. Under high-pressure conditions, the leakage of the valve will become increasingly larger. In severe cases, the leakage can reach more than 80% of the rated displacement of the metering pump. Therefore, after the metering pump has been running continuously for a period of time (generally not more than 15 days), it is difficult to accurately measure and control the dosing flow rate, and thus it is difficult to meet the production needs of the gas well.

[0014] 2. It is extremely difficult to manufacture and purchase high-pressure, small-displacement metering pumps.

[0015] It is common knowledge in this field that the pressure of injecting foaming agents into gas wells is generally as high as 5 to 40 MPa; currently, it is difficult to purchase metering pumps with a rated pressure of 5 to 40 MPa and a rated displacement of less than 1 liter / hour in the domestic and foreign markets; there is no public information on metering pumps with a displacement of less than 1 liter / hour.

[0016] 3. This method has low pump efficiency and high energy consumption.

[0017] It is known from common knowledge in the field that: taking a dosing flow rate of 0.5 liters / hour as an example, due to the difficulty in purchasing high-pressure, small-displacement metering pumps, a metering pump with a rated displacement of 5 liters / hour is generally selected, and then its cam mechanism is used to control the plunger (or diaphragm) stroke to be reduced to 10%, so that its displacement is reduced to 10% of the rated displacement of 5 liters / hour, thereby adjusting the dosing flow rate to 0.5 liters / hour; therefore, its pump efficiency is very low and energy consumption is greatly wasted.

[0018] 4. When this method is applied to cluster wells, it is necessary to run multiple metering pumps, which is not only complicated in process but also requires a lot of management work.

[0019] It is common knowledge in the art that the Sichuan Weiyuan shale cluster wells are generally arranged and drilled with 6 to 10 gas wells, which requires the installation and operation of 12 to 20 metering pumps, that is, 2 metering pumps are required for each gas well; among them, 6 to 10 metering pumps are required to inject foaming agents into 6 to 10 gas wells respectively, and another 6 to 10 metering pumps are required to inject defoaming agents into 6 to 10 gas wells respectively.

[0020] In summary, the above-mentioned dosing system and method have many defects when dosing chemicals in oil and gas wells and pipelines and cannot meet production requirements. Summary of the Invention

[0021] The "agent" in the present invention is also called a functional chemical agent, a gas (or oil) recovery auxiliary agent, sometimes referred to as a medicine or auxiliary agent, and is liquid at room temperature and pressure.

[0022] In the present invention, "dosing" is a general term for adding functional chemicals, and sometimes specifically refers to the process of adding liquid chemicals into oil and gas wells and oil and gas pipelines.

[0023] The "dosage" in the present invention is referred to as dosage for short; it refers to the volume or weight of the added functional chemical agent, and sometimes also refers to the dosing flow rate.

[0024] The "dosing flow rate" in the present invention is sometimes referred to as the dosing amount or the dosage, which is an abbreviation for the flow rate of the functional chemical agent, and generally refers to the volume flow rate of the functional chemical agent.

[0025] The "Christmas tree" in the present invention is generally called a gas tree when used in a gas well.

[0026] The "plunger stroke control dial" in the present invention refers to a system or device for controlling the stroke of the plunger (or diaphragm) of a plunger pump (or diaphragm pump) so as to further control the displacement of the plunger pump (or diaphragm pump); it is referred to as a turntable, wheel, or handwheel.

[0027] The first technical problem to be solved by the present invention is to provide a dosing system; this dosing system overcomes the defects of existing dosing systems, can effectively solve the metering, adjustment and control problems of dosing in oil and gas wells and pipelines, can save energy and reduce consumption, and meet production requirements; it has the advantages of easy implementation, safety and reliability, wide application, and easy promotion.

[0028] The second technical problem to be solved by the present invention is to provide a dosing method; this method overcomes the defects of existing dosing methods, can effectively solve the metering, adjustment and control problems existing in the dosing of oil and gas wells and pipelines, can save energy and reduce consumption, and meet production requirements; it has the advantages of easy implementation, safety and reliability, wide application, and easy promotion.

[0029] In order to solve the above-mentioned first technical problem, the first technical solution adopted by the present invention is:

[0030] The present invention provides a dosing system, comprising a container, a pump inlet pipe, a high-pressure pump, a pump outlet tee, a reflux pipe, a reflux regulating valve, a reflux pipe, a drug delivery pipe, a drug distribution tee, a first dosing pipe, a first regulating valve, a first metering pipe, a first high-pressure micro flowmeter, a first drug distribution pipe, a second dosing pipe, a second regulating valve, a second metering pipe, and a second high-pressure micro flowmeter;

[0031] The lower portion of the container is connected to one end of a pump inlet pipe, and the other end of the pump inlet pipe is connected to an inlet of a high-pressure pump;

[0032] The high-pressure pump outlet is connected to one end of the pump outlet tee;

[0033] The side interface of the pump outlet tee is connected to the inlet of the reflux regulating valve through a reflux pipe fitting, and the other end of the pump outlet tee is connected to one end of the drug delivery tube;

[0034] The outlet of the reflux regulating valve is connected to the bottom or / and lower part of the container via a reflux pipe;

[0035] The other end of the drug delivery tube is connected to one end of the drug dispensing tee;

[0036] The side interface of the medicine distributing tee is connected to one end of the first medicine distributing pipe, and the other end is connected to one end of the first medicine adding pipe;

[0037] The other end of the first dosing tube is connected to the first high-pressure micro flow meter through the first regulating valve and the first metering pipe in sequence;

[0038] The other end of the first medicine distributing pipe is connected to the second high-pressure micro flow meter through the second medicine adding pipe, the second regulating valve and the second metering pipe fitting in sequence.

[0039] Furthermore, the container is any one of a normal pressure container, a pressure container, a cube container, a rectangular parallelepiped container, and a cylindrical container;

[0040] The high-pressure pump is any one of a centrifugal pump, a positive displacement pump, a rotor pump, a reciprocating pump, an electromagnetic pump, a magnetic pump, a gear pump, a metering pump, a membrane pump, and a diaphragm pump;

[0041] The high-pressure micro flowmeter is any one of a high-pressure gear flowmeter, an ultrasonic flowmeter, a high-pressure turbine flowmeter, a high-pressure metal tube float flowmeter, and a rotor flowmeter, and its measuring range is 5 to 60,000 ml / h;

[0042] The regulating valves are any one of needle valves, stop valves, gate valves, electric valves, solenoid valves, and electric regulating valves;

[0043] The reflux regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve;

[0044] The pipe fittings are any kind of metal pipe fittings;

[0045] All tees are any type of metal tees;

[0046] The drug delivery tube is any one of a metal tube, an aluminum-plastic tube, a steel-plastic tube, a high-pressure hose, a composite tube, and a pipe fitting;

[0047] The dosing pipe is any one of a metal pipe, an aluminum-plastic pipe, a steel-plastic pipe, a high-pressure hose, a composite pipe, and a pipe fitting;

[0048] The medicine dispensing pipe is any one of a metal pipe, an aluminum-plastic pipe, a steel-plastic pipe, a high-pressure hose, a composite pipe, and a pipe fitting;

[0049] The pump inlet pipe is a pipeline and / or pipe fitting made of any material;

[0050] The return pipe is a pipeline and / or pipe fitting made of any material.

[0051] Furthermore, in order to prevent high-pressure natural gas and / or liquid in the gas well or pipeline from impacting and damaging the high-pressure micro flowmeter, a first check valve is arranged behind the first high-pressure micro flowmeter near one end of the gas well, and the outlet of the first high-pressure micro flowmeter is connected to the first check valve through a first check pipe fitting; a second check valve is arranged behind the second high-pressure micro flowmeter near one end of the gas well, and the outlet of the second high-pressure micro flowmeter is connected to the second check valve through a second check pipe fitting.

[0052] Furthermore, in order to solve the problem of no industrial power supply in gas wells, the power supply of the high-voltage micro flowmeter is any one of dry cells, storage batteries, solar power generation, wind power generation or any combination of any two or more thereof.

[0053] Furthermore, in order to solve the problem of unattended gas wells, the flow signal of the high-pressure micro flow meter is remotely transmitted to a remote location and / or management area, and the power source required for remote transmission of the flow signal is any one of dry cells, storage batteries, solar power generation, wind power generation, or any combination of any two or more thereof.

[0054] Furthermore, in order to solve the problem of no industrial power supply in the gas well, the high-pressure pump is powered by any one of solar power generation, wind power generation, battery power supply, generator power generation, or any combination of any two or more of them.

[0055] Furthermore, in order to solve the problem of unattended gas wells, the high-pressure pump is started and stopped regularly using a time relay.

[0056] Furthermore, in order to solve the problem of unattended gas wells, the high-pressure pump is started and stopped remotely by a remote computer.

[0057] In order to solve the above-mentioned first technical problem, the second technical solution adopted by the present invention is:

[0058] The present invention provides a dosing system, comprising a container, a pump inlet pipe, a high-pressure pump, a pump outlet tee, a reflux pipe fitting, a reflux regulating valve, a reflux pipe, a drug delivery pipe, a drug distribution tee fitting, a first dosing pipe, a first regulating valve, a first metering pipe fitting, a first high-pressure micro-flowmeter, a first drug distribution pipe, a second drug distribution tee fitting, a second dosing pipe, a second regulating valve, a second metering pipe fitting, a second high-pressure micro-flowmeter, a second drug distribution pipe, a third dosing pipe, a third regulating valve, a third metering pipe fitting, and a third high-pressure micro-flowmeter;

[0059] The lower portion of the container is connected to one end of a pump inlet pipe, and the other end of the pump inlet pipe is connected to an inlet of a high-pressure pump;

[0060] The high-pressure pump outlet is connected to one end of the pump outlet tee;

[0061] The side interface of the pump outlet tee is connected to the inlet of the reflux regulating valve through a reflux pipe fitting, and the other end of the pump outlet tee is connected to one end of the drug delivery tube;

[0062] The outlet of the reflux regulating valve is connected to the bottom or / and lower part of the container via a reflux pipe;

[0063] The other end of the drug delivery tube is connected to one end of the drug dispensing tee;

[0064] The side interface of the medicine distributing tee is connected to one end of the first medicine distributing pipe, and the other end is connected to one end of the first medicine adding pipe;

[0065] The other end of the first dosing tube is connected to the first high-pressure micro flow meter through the first regulating valve and the first metering pipe in sequence;

[0066] The other end of the first medicine distributing pipe is connected to one end of the second medicine distributing tee;

[0067] The side interface of the second medicine distributing tee is connected to one end of the second medicine dosing pipe, and the other end is connected to one end of the second medicine distributing pipe;

[0068] The other end of the second dosing pipe is connected to the second high-pressure micro flow meter through the second regulating valve and the second metering pipe in sequence;

[0069] The other end of the second drug distributing pipe is connected to the third high-pressure micro flow meter through the third drug adding pipe, the third regulating valve and the third metering pipe fitting in sequence.

[0070] Furthermore, the container is any one of a normal pressure container, a pressure container, a cube container, a rectangular parallelepiped container, and a cylindrical container;

[0071] The high-pressure pump is any one of a centrifugal pump, a positive displacement pump, a rotor pump, a reciprocating pump, an electromagnetic pump, a magnetic pump, a gear pump, a metering pump, a membrane pump, and a diaphragm pump;

[0072] The high-pressure micro flowmeter is any one of a high-pressure gear flowmeter, an ultrasonic flowmeter, a high-pressure turbine flowmeter, a high-pressure metal tube float flowmeter, and a rotor flowmeter, and its measuring range is 5 to 60,000 ml / h;

[0073] The regulating valves are any one of needle valves, stop valves, gate valves, electric valves, solenoid valves, and electric regulating valves;

[0074] The reflux regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve;

[0075] The pipe fittings are any kind of metal pipe fittings;

[0076] All tees are any type of metal tees;

[0077] The drug delivery tube is any one of a metal tube, an aluminum-plastic tube, a steel-plastic tube, a high-pressure hose, a composite tube, and a pipe fitting;

[0078] The dosing pipe is any one of a metal pipe, an aluminum-plastic pipe, a steel-plastic pipe, a high-pressure hose, a composite pipe, and a pipe fitting;

[0079] The medicine dispensing pipe is any one of a metal pipe, an aluminum-plastic pipe, a steel-plastic pipe, a high-pressure hose, a composite pipe, and a pipe fitting;

[0080] The pump inlet pipe is a pipeline and / or pipe fitting made of any material;

[0081] The return pipe is a pipeline and / or pipe fitting made of any material.

[0082] Furthermore, in order to prevent the backflow of high-pressure natural gas or / and liquid from impacting and damaging the high-pressure micro flowmeter, a first check valve is arranged behind the first high-pressure micro flowmeter near one end of the gas well, and the outlet of the first high-pressure micro flowmeter is connected to the first check valve through a first check pipe fitting; a second check valve is arranged behind the second high-pressure micro flowmeter near one end of the gas well, and the outlet of the second high-pressure micro flowmeter is connected to the second check valve through a second check pipe fitting; a third check valve is arranged behind the third high-pressure micro flowmeter near one end of the gas well, and the outlet of the third high-pressure micro flowmeter is connected to the third check valve through a third check pipe fitting.

[0083] Furthermore, in order to solve the problem of no industrial power supply in gas wells, the power supply of the high-voltage micro flowmeter is any one of dry cells, storage batteries, solar power generation, wind power generation or any combination of any two or more thereof.

[0084] Furthermore, in order to solve the problem of unattended gas wells, the flow signal of the high-pressure micro flow meter is remotely transmitted to a remote location and / or management area, and the power source required for remote transmission of the flow signal is any one of dry cells, storage batteries, solar power generation, wind power generation, or any combination of any two or more thereof.

[0085] Furthermore, in order to solve the problem of no industrial power supply in the gas well, the high-pressure pump is powered by any one of solar power generation, wind power generation, battery power supply, generator power generation, or any combination of any two or more of them.

[0086] Furthermore, in order to solve the problem of unattended gas wells, the high-pressure pump is started and stopped regularly using a time relay.

[0087] Furthermore, in order to solve the problem of unattended gas wells, the high-pressure pump is started and stopped remotely by a remote computer.

[0088] In order to solve the above-mentioned first technical problem, the third technical solution adopted by the present invention is:

[0089] The present invention provides a drug dosing system, comprising a container, a pump inlet pipe, a high-pressure pump, a tee, pipe fittings, a reflux regulating valve, a reflux pipe, a drug delivery pipe, a regulating valve, pipe fittings, and a high-pressure micro flow meter;

[0090] The lower portion of the container is connected to one end of a pump inlet pipe, and the other end of the pump inlet pipe is connected to an inlet of a high-pressure pump;

[0091] The high-pressure pump outlet is connected to one end of a tee;

[0092] The side interface of the three-way is connected to the inlet of the reflux regulating valve through a pipe fitting, and the other end of the three-way is connected to one end of the drug delivery tube;

[0093] The outlet of the reflux regulating valve is connected to the bottom or / and lower part of the container via a reflux pipe;

[0094] The other end of the medicine delivery tube is connected to a high-pressure micro flow meter through a regulating valve and a pipe fitting in sequence.

[0095] Furthermore, the container is any one of a normal pressure container, a pressure container, a cube container, a rectangular parallelepiped container, and a cylindrical container;

[0096] The high-pressure pump is any one of a centrifugal pump, a positive displacement pump, a rotor pump, a reciprocating pump, an electromagnetic pump, a magnetic pump, a gear pump, a metering pump, a membrane pump, and a diaphragm pump;

[0097] The high-pressure micro flowmeter is any one of a high-pressure gear flowmeter, an ultrasonic flowmeter, a high-pressure turbine flowmeter, a high-pressure metal tube float flowmeter, and a rotor flowmeter, and its measuring range is 5 to 60,000 ml / h;

[0098] The regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve;

[0099] The reflux regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve;

[0100] The pipe fitting is any type of metal pipe fitting;

[0101] The tee is any type of metal tee;

[0102] The drug delivery tube is any one of a metal tube, an aluminum-plastic tube, a steel-plastic tube, a high-pressure hose, a composite tube, and a pipe fitting;

[0103] The pump inlet pipe is a pipeline and / or pipe fitting made of any material;

[0104] The return pipe is a pipeline and / or pipe fitting made of any material.

[0105] Furthermore, in order to prevent the high-pressure natural gas and / or liquid from flowing back and impacting and damaging the high-pressure micro flowmeter, a check valve is set behind the high-pressure micro flowmeter near one end of the gas well, and the outlet of the high-pressure micro flowmeter is connected to the check valve through a pipe.

[0106] Furthermore, in order to solve the problem of no industrial power supply in gas wells, the power supply of the high-voltage micro flowmeter is any one of dry cells, storage batteries, solar power generation, wind power generation or any combination of any two or more thereof.

[0107] Furthermore, in order to solve the problem of unattended gas wells, the flow signal of the high-pressure micro flow meter is remotely transmitted to a remote location and / or management area, and the power source required for remote transmission of the flow signal is any one of dry cells, storage batteries, solar power generation, wind power generation, or any combination of any two or more thereof.

[0108] Furthermore, in order to solve the problem of no industrial power supply in the gas well, the high-pressure pump is powered by any one of solar power generation, wind power generation, battery power supply, generator power generation, or any combination of any two or more of them.

[0109] Furthermore, in order to solve the problem of unattended gas wells, the high-pressure pump is started and stopped regularly using a time relay.

[0110] Furthermore, in order to solve the problem of unattended gas wells, the high-pressure pump is started and stopped remotely by a remote computer.

[0111] To solve the second technical problem, the dosing method of the dosing system of the present invention adopts a first technical solution: the dosing method of injecting a foaming agent into two gas wells by the dosing system comprises the following steps:

[0112] 1) Connecting the outlet of the first check valve to the first casing valve of the first gas well using a first connecting pipe fitting, and connecting the outlet of the second check valve to the second casing valve of the second gas well using a second connecting pipe fitting;

[0113] 2) First open the first regulating valve and the second regulating valve, and then open the first casing valve and the second casing valve;

[0114] 3) Open the reflux regulating valve;

[0115] 4) Start the high-pressure pump;

[0116] 5) gradually reducing the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well;

[0117] 6) adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well;

[0118] 7) According to the instantaneous flow reading of the second high-pressure micro flow meter, adjust the opening of the second regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the second high-pressure micro flow meter meets the dosing flow requirement of the second gas well.

[0119] Furthermore, in order to solve the problem of injecting the foaming agent into 4 to 50 gas wells, the dosing system is used to inject the foaming agent into any number of the 4 to 50 gas wells.

[0120] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 gas wells, the dosing system is used to inject corrosion inhibitors, bactericides, scale inhibitors, any one of corrosion inhibitors and scale inhibitors, or a mixture of any two or more in any proportion into any number of gas wells among 1 to 50 gas wells.

[0121] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 oil wells and / or water injection wells, the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of the 1 to 50 oil wells and / or water injection wells.

[0122] To solve the second technical problem, the second technical solution adopted by the dosing method of the dosing system of the present invention is: the dosing method of injecting foaming agent into three gas wells by the dosing system includes the following steps:

[0123] 1) Connecting the outlet of the first check valve to the first casing valve of the first gas well using a first connecting pipe fitting, connecting the outlet of the second check valve to the second casing valve of the second gas well using a second connecting pipe fitting, and connecting the outlet of the third check valve to the third casing valve of the third gas well using a third connecting pipe fitting;

[0124] 2) First open the first regulating valve, the second regulating valve, and the third regulating valve, and then open the first casing valve, the second casing valve, and the third casing valve;

[0125] 3) Open the reflux regulating valve;

[0126] 4) Start the high-pressure pump;

[0127] 5) gradually reducing the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter or / and the third high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well or / and the third gas well;

[0128] 6) adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well;

[0129] 7) adjusting the opening of the second regulating valve and / or the reflux regulating valve according to the instantaneous flow reading of the second high-pressure micro-flow meter until the instantaneous flow reading of the second high-pressure micro-flow meter meets the dosing flow requirement of the second gas well;

[0130] 8) According to the instantaneous flow reading of the third high-pressure micro flow meter, adjust the opening of the third regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the third high-pressure micro flow meter meets the dosing flow requirement of the third gas well.

[0131] Furthermore, in order to solve the problem of injecting the foaming agent into 4 to 50 gas wells, the dosing system is used to inject the foaming agent into any number of the 4 to 50 gas wells.

[0132] Furthermore, in order to solve the problem of injecting corrosion inhibitors, bactericides, scale inhibitors, corrosion inhibitors and other functional chemicals into 1 to 50 gas wells, the dosing system is used to inject any one of corrosion inhibitors, bactericides, scale inhibitors, corrosion inhibitors and any mixture of any two or more in any proportion into any number of gas wells among 1 to 50 gas wells.

[0133] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 oil wells and / or water injection wells, the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of the 1 to 50 oil wells and / or water injection wells.

[0134] To solve the second technical problem, the third technical solution adopted by the dosing method of the dosing system of the present invention is: the dosing method of injecting a foaming agent into a gas well by the dosing system includes the following steps:

[0135] 1) Use connecting pipe fittings to connect the check valve outlet to the casing valve of the gas well;

[0136] 2) Open the regulating valve first, then open the casing valve;

[0137] 3) Open the reflux regulating valve;

[0138] 4) Start the high-pressure pump;

[0139] 5) Adjust the opening of the regulating valve and / or the reflux regulating valve until the instantaneous dosing flow reading of the high-pressure micro flow meter meets the dosing flow requirement of the gas well.

[0140] Furthermore, in order to solve the problem of injecting the foaming agent into 4 to 50 gas wells, the dosing system is used to inject the foaming agent into any number of the 4 to 50 gas wells.

[0141] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 gas wells, the dosing system is used to inject corrosion inhibitors, bactericides, scale inhibitors, any one of corrosion inhibitors and scale inhibitors, or a mixture of any two or more in any proportion into any number of gas wells among 1 to 50 gas wells.

[0142] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 oil wells and / or water injection wells, the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of the 1 to 50 oil wells and / or water injection wells.

[0143] To solve the second technical problem, the fourth technical solution adopted by the dosing method of the dosing system of the present invention is: the dosing method of injecting defoaming agent into the surface pipelines of two gas wells by the dosing system comprises the following steps:

[0144] 1) Installing a first valve on a first surface pipeline of a first gas well, and installing a second valve on a second surface pipeline of a second gas well;

[0145] 2) Connecting the outlet of the first check valve to the first valve with a first connecting pipe, and connecting the outlet of the second check valve to the second valve with a second connecting pipe;

[0146] 3) First open the first regulating valve and the second regulating valve, and then open the first valve and the second valve;

[0147] 4) Open the reflux regulating valve;

[0148] 5) Start the high-pressure pump;

[0149] 6) gradually reducing the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well;

[0150] 7) adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well;

[0151] 8) According to the instantaneous flow reading of the second high-pressure micro flow meter, adjust the opening of the second regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the second high-pressure micro flow meter meets the dosing flow requirement of the second gas well.

[0152] Furthermore, in order to solve the problem of adding defoaming agent to 4 to 50 gas production pipelines, the dosing system is used to add defoaming agent to any number of the 4 to 50 gas production pipelines.

[0153] Furthermore, in order to solve the problem of adding functional chemicals to 1 to 50 gas production pipelines, the dosing system is used to add corrosion inhibitors, bactericides, scale inhibitors, any one of corrosion inhibitors and scale inhibitors, or a mixture of any two or more in any proportion to any number of the 1 to 50 gas production pipelines.

[0154] Furthermore, in order to solve the problem of adding functional chemicals to 1 to 50 gas injection pipelines, the dosing system is used to add any one of antifreeze, deblocking agents, prevention and control agents, hydrate inhibitors, antifreeze and deblocking agents, corrosion inhibitors, scale inhibitors, cleaning agents, and functional chemicals, or a mixture of any two or more in any proportion, to any number of the 1 to 50 gas injection pipelines.

[0155] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 oil production pipelines or / and water injection pipelines, the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of the 1 to 50 oil production pipelines or / and water injection pipelines.

[0156] To solve the second technical problem, the fifth technical solution adopted by the dosing method of the dosing system of the present invention is: the dosing method of injecting defoaming agent into the surface pipelines of three gas wells by the dosing system comprises the following steps:

[0157] 1) Installing a first valve on a first surface pipeline of a first gas well, installing a second valve on a second surface pipeline of a second gas well, and installing a third valve on a third surface pipeline of a third gas well;

[0158] 2) Connecting the outlet of the first check valve to the first valve with a first connecting pipe, connecting the outlet of the second check valve to the second valve with a second connecting pipe, and connecting the outlet of the third check valve to the third valve with a third connecting pipe;

[0159] 3) First open the first regulating valve, the second regulating valve, and the third regulating valve, and then open the first valve, the second valve, and the third valve;

[0160] 4) Open the reflux regulating valve;

[0161] 5) Start the high-pressure pump;

[0162] 6) gradually reducing the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter or / and the third high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well or / and the third gas well;

[0163] 7) adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well;

[0164] 8) adjusting the opening of the second regulating valve and / or the reflux regulating valve according to the instantaneous flow reading of the second high-pressure micro-flow meter until the instantaneous flow reading of the second high-pressure micro-flow meter meets the dosing flow requirement of the second gas well;

[0165] 9) According to the instantaneous flow reading of the third high-pressure micro flow meter, adjust the opening of the third regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the third high-pressure micro flow meter meets the dosing flow requirement of the third gas well.

[0166] Furthermore, in order to solve the problem of adding defoaming agent to 4 to 50 gas production pipelines, the dosing system is used to add defoaming agent to any number of the 4 to 50 gas production pipelines.

[0167] Furthermore, in order to solve the problem of adding functional chemicals to 1 to 50 gas production pipelines, the dosing system is used to add corrosion inhibitors, bactericides, scale inhibitors, any one of corrosion inhibitors and scale inhibitors, or a mixture of any two or more in any proportion to any number of the 1 to 50 gas production pipelines.

[0168] Furthermore, in order to solve the problem of adding functional chemicals to 1 to 50 gas injection pipelines, the dosing system is used to add any one of antifreeze, deblocking agents, prevention and control agents, hydrate inhibitors, antifreeze and deblocking agents, corrosion inhibitors, scale inhibitors, cleaning agents, and functional chemicals, or a mixture of any two or more in any proportion, to any number of the 1 to 50 gas injection pipelines.

[0169] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 oil production pipelines or / and water injection pipelines, the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of the 1 to 50 oil production pipelines or / and water injection pipelines.

[0170] To solve the second technical problem, the sixth technical solution adopted by the dosing method of the dosing system of the present invention is: the dosing method of injecting a defoaming agent into a surface pipeline of a gas well by the dosing system comprises the following steps:

[0171] 1) Install valves on the surface pipeline of the gas well;

[0172] 2) Use the connecting pipe to connect the check valve outlet to the valve;

[0173] 3) Open the regulating valve first, then open the valve;

[0174] 4) Open the reflux regulating valve;

[0175] 5) Start the high-pressure pump;

[0176] 6) Adjust the opening of the regulating valve and / or the reflux regulating valve until the instantaneous dosing flow reading of the high-pressure micro flow meter meets the dosing flow requirement required by the gas well surface pipeline.

[0177] Furthermore, in order to solve the problem of adding defoaming agent to 4 to 50 gas production pipelines, the dosing system is used to add defoaming agent to any number of the 4 to 50 gas production pipelines.

[0178] Furthermore, in order to solve the problem of adding functional chemicals to 1 to 50 gas production pipelines, the dosing system is used to add corrosion inhibitors, bactericides, scale inhibitors, any one of corrosion inhibitors and scale inhibitors, or a mixture of any two or more in any proportion to any number of the 1 to 50 gas production pipelines.

[0179] Furthermore, in order to solve the problem of adding functional chemicals to 1 to 50 gas injection pipelines, the dosing system is used to add any one of antifreeze, deblocking agents, prevention and control agents, hydrate inhibitors, antifreeze and deblocking agents, corrosion inhibitors, scale inhibitors, cleaning agents, and functional chemicals, or a mixture of any two or more in any proportion, to any number of the 1 to 50 gas injection pipelines.

[0180] Furthermore, in order to solve the problem of injecting functional chemicals into 1 to 50 oil production pipelines or / and water injection pipelines, the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of the 1 to 50 oil production pipelines or / and water injection pipelines.

[0181] The beneficial effects of the present invention are as follows: the present invention overcomes the defects of the existing dosing system, can effectively solve the metering, adjustment and control problems existing in the dosing of oil and gas wells and pipelines, can save energy and reduce consumption, and meet production requirements; it has the advantages of easy implementation, safety and reliability, wide application, and easy promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0182] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0183] Figure 1 Schematic diagram of the system for injecting foaming agent into existing gas wells;

[0184] Figure 2 Schematic diagram of the defoamer injection system for existing gas wells;

[0185] Figure 3 Schematic diagram of the dosing system in Example 1;

[0186] Figure 4 This is a schematic diagram of the dosing system for the comparative example of the production test in Example 1;

[0187] Figure 5 This is a schematic diagram of the dosing system in Example 2;

[0188] Figure 6 This is a schematic diagram of the dosing system in Example 4;

[0189] Figure 7 This is a schematic diagram of the dosing system in Example 6;

[0190] Figure 8 This is a schematic diagram of the dosing system for the comparative example of the production test in Example 6;

[0191] Figure 9 This is a schematic diagram of the dosing system in Example 7;

[0192] Figure 10 This is a schematic diagram of the dosing system in Example 8;

[0193] Figure 11 This is a schematic diagram of a dosing method for injecting a foaming agent into two gas wells using the dosing system in Example 14;

[0194] Figure 12 This is a schematic diagram of a dosing method for injecting foaming agent into three gas wells using the dosing system in Example 15;

[0195] Figure 13 This is a schematic diagram of a dosing method for injecting a foaming agent into a gas well using the dosing system in Example 16;

[0196] Figure 14 This is a schematic diagram of a dosing method for injecting defoaming agent into the surface pipelines of two gas wells using the dosing system in Example 17;

[0197] Figure 15 This is a schematic diagram of a dosing method for injecting defoaming agent into the surface pipelines of three gas wells using the dosing system in Example 18;

[0198] Figure 16 This is a schematic diagram of the dosing method for injecting defoaming agent into the surface pipeline of a gas well using the dosing system in Example 19. DETAILED DESCRIPTION

[0199] Example 1

[0200] See also Figure 3 As shown, a dosing system includes a container 300, a pump inlet pipe 301, a high-pressure pump 302, a pump outlet tee 303, a reflux pipe 304, a reflux regulating valve 305, a reflux pipe 306, a drug delivery pipe 307, a drug distribution tee 308, a first dosing pipe 309, a first regulating valve 310, a first metering pipe 311, a first high-pressure micro flowmeter 312, a first drug distribution pipe 313, a second dosing pipe 314, a second regulating valve 315, a second metering pipe 316, and a second high-pressure micro flowmeter 317;

[0201] The lower portion of the container 300 is connected to one end of a pump inlet pipe 301, and the other end of the pump inlet pipe 301 is connected to the inlet of a high-pressure pump 302.

[0202] The outlet of the high-pressure pump 302 is connected to one end of the pump outlet tee 303;

[0203] The side interface of the pump outlet tee 303 is connected to the inlet of the reflux regulating valve 305 through a reflux pipe 304, and the other end of the pump outlet tee 303 is connected to one end of the drug delivery tube 307;

[0204] The outlet of the reflux regulating valve 305 is connected to the bottom or / and lower part of the container 300 via a reflux pipe 306;

[0205] The other end of the drug delivery tube 307 is connected to one end of the drug dispensing tee 308;

[0206] The side interface of the medicine distributing tee 308 is connected to one end of the first medicine distributing pipe 313, and the other end is connected to one end of the first medicine adding pipe 309;

[0207] The other end of the first dosing tube 309 is connected to the first high-pressure micro flow meter 312 through the first regulating valve 310 and the first metering pipe 311 in sequence;

[0208] The other end of the first drug dispensing pipe 313 is connected to the second high-pressure micro flow meter 317 through the second drug adding pipe 314 , the second regulating valve 315 , and the second metering pipe 316 in sequence.

[0209] Production test example of this embodiment:

[0210] Take the Wei 202H82 shale gas platform in Weiyuan, Sichuan as an example.

[0211] The platform is equipped with 6 gas wells, with the maximum casing pressure of a single well reaching 15 MPa. The dosage of foaming agent and defoaming agent for a single well is 5-8 liters / day of original liquid or 20-32 liters / day of diluted liquid (i.e., the original liquid is diluted 4 times and injected), which is equivalent to a dosing flow rate of 0.8-1.3 liters / hour of diluted liquid. If one gas well uses one metering pump to inject foaming agent and another metering pump to inject defoaming agent, the platform needs to install and operate 12 metering pumps, which will inevitably lead to complicated equipment, complex processes and heavy management workload.

[0212] According to the common knowledge in this field, the metering pump with a rated pressure of 20 MPa that can be purchased on the domestic market currently has an adjustable rated displacement range of 0.5 to 5 liters / hour (corresponding to a plunger stroke of 10 to 100%) and a rated power of 0.37KW.

[0213] It can be seen from this that if two metering pumps are used to inject foam removal agent and defoaming agent respectively in one well of this platform, the plunger stroke of the metering pump needs to be controlled at 16%, which is not only difficult to control but also has low pump efficiency and large waste of electricity.

[0214] According to the common knowledge in this field, the metering pump is provided with a "plunger stroke control dial" engraved with the percentage of the plunger stroke, and its lowest scale value is 1%. Rotating the dial can control the plunger stroke percentage corresponding to the scale value. Since the valve loss at the outlet of the metering pump is not linearly related to the plunger stroke length, the plunger stroke percentage and the displacement percentage of the metering pump are not in a one-to-one correspondence, nor are they in a linear or proportional relationship. That is, after adjusting the scale value of the dial to 16%, the plunger stroke of the metering pump is only adjusted to 16% of the full theoretical stroke, and The displacement of the metering pump has not been adjusted to 16% of the rated displacement (at this time, the actual displacement of the metering pump may be greater than 16% of the rated displacement, or it may be less than 16% of the rated displacement, and the error may exceed 30%, and the smaller the plunger stroke percentage, the greater the error); therefore, adjusting the plunger stroke percentage of the turntable cannot accurately adjust the displacement of the metering pump; especially for a metering pump that has been running for a period of time, its valve loss is very different from its factory calibration value. The method of adjusting the plunger stroke control turntable cannot effectively measure and adjust the displacement of the metering pump.

[0215] To solve the above problems, the platform began to apply the present invention for production testing on June 1, 2021. The technical solution adopted is:

[0216] (1) When injecting the foaming agent, first use a metering pump with a rated displacement of 15 liters / hour and a rated pressure of 20 MPa to increase the pressure of the foaming agent to a level exceeding the highest casing pressure of the six wells; then allow the foaming agent to enter the dosing manifold; and then allow the foaming agent to enter the six dosing pipelines connected to the oil casing annuli of the six gas wells. When it is necessary to adjust the dosing flow of the foaming agent, the operator adjusts the flow reading (digital display) displayed by the high-pressure micro flow meter (flow range 0.06 to 24 liters / hour) on the dosing pipeline; adjusts the needle valve or metering pump plunger stroke control mechanism (such as the plunger stroke control dial) installed on the dosing pipeline, and the reflux regulating valve installed at the metering pump outlet; and the foaming agent dosing flow of each well can be adjusted to the required flow.

[0217] (2) Similarly, when adding defoaming agent, first use a metering pump with a rated displacement of 15 liters / hour and a rated pressure of 20 MPa to increase the defoaming agent pressure to a level exceeding the maximum pressure (also known as back pressure or oil pressure) of the surface gas production pipeline of the six wells; then allow the defoaming agent to enter the dosing manifold; and then allow the defoaming agent to enter the six dosing pipelines connected to the surface gas production pipelines of the six gas wells. When it is necessary to adjust the dosing flow of the defoaming agent, the operator adjusts the needle valve or metering pump plunger stroke control mechanism set on the dosing pipeline and the reflux regulating valve set at the metering pump outlet according to the flow reading (digital display) displayed on the high-pressure micro flow meter on the dosing pipeline; and can adjust the defoaming agent dosing flow of each well to the required flow.

[0218] The production and operation results of the platform after applying the above technical solutions are as follows:

[0219] (1) The two metering pumps used can fully meet the production needs of injecting foaming agents and defoaming agents into 6 wells at the same time: using 1 metering pump and 6 dosing pipelines, 6 high-pressure micro flow meters, and 1 metering pump outlet return flow regulating valve, 6 gas wells can be injected with foaming agents at the same time; similarly, using 1 metering pump and 6 dosing pipelines, 6 high-pressure micro flow meters, and 1 metering pump outlet return flow regulating valve, 6 gas wells can be injected with defoaming agents at the same time.

[0220] (2) The high-pressure micro flowmeter used has a pressure resistance of 40 MPa and a flow range of 0.06 to 24 liters / hour, which fully meets the production needs of the platform's foam removal agent and defoamer dilution dosing flow rate of 0.8 to 1.3 liters / hour; it can accurately display, remotely transmit and read the instantaneous dosing flow rate and cumulative dosing flow rate of each gas well in the form of a digital display, and can effectively correct the error in the estimated displacement value of the metering pump obtained by relying on the metering pump plunger stroke control dial (the error can be as high as 30% or more).

[0221] It is known from the common knowledge in this field that there is currently no public information or successful precedent for using a flow meter at the outlet of a metering pump and / or a gas well dosing pipeline, nor is there any public information or successful precedent for using a high-pressure micro flow meter with a pressure resistance of 40 MPa and a flow range of 0.06 to 24 liters / hour.

[0222] (3) When injecting foaming agent or defoaming agent, the metering pump reflux regulating valve used has a very prominent beneficial regulating effect: when the number of gas wells is 2 or more, the dosing flow rates between the dosing lines seriously affect each other, and the more gas wells there are, the more serious the influence is; that is, when the dosing flow rate of one dosing line is adjusted, the dosing flow rates of other dosing lines will automatically change, resulting in the dosing amount of other dosing lines not being able to meet the production needs of the gas wells; therefore, when the number of gas wells is 2 or more, it is impossible to adjust the dosing amount of each well to the required dosing flow rate by relying solely on the needle valve, the plunger stroke control dial of the metering pump and the high-pressure micro flow meter; however, after properly adjusting the opening of the reflux regulating valve (or needle valve) at the outlet of the metering pump, the needle valve and the plunger stroke control dial of the metering pump can be used to accurately adjust the dosing amount of each well to the required dosing flow rate according to the reading of the high-pressure micro flow meter.

[0223] (4) The metering pump reflux regulating valve used has another very prominent beneficial regulating effect: since the amount of dosing required for gas wells is only 0.8 to 1.3 liters per hour, it is difficult to purchase suitable high-pressure, small-displacement metering pumps on the domestic market. If this reflux regulating valve is used, not only can a metering pump with a larger displacement be used (purchased) to add drugs to one gas well, but it can also meet the actual needs of gradually putting multiple gas wells into production in a cluster well field.

[0224] Taking the Wei 202H82 shale gas platform as an example, the six wells of the platform were put into production gradually over several days, rather than simultaneously. The platform initially added drugs to one well, and then gradually increased the number of wells to six. Therefore, if a reflux regulating valve is not provided at the pump outlet, the technical solution of the present invention of using a metering pump with a rated displacement of 15 liters / hour (the minimum displacement must not be less than 1.5 liters / hour, which has far exceeded the maximum drug addition flow rate of a single well) and a rated pressure of 20 MPa to inject foaming agents into six wells will not be implemented in the actual production of the platform or will result in a large amount of drug waste.

[0225] (5) The rated power of one metering pump with a rated displacement of 15 liters / hour and a rated pressure of 20 MPa is 0.75 kW, and the total rated power of two metering pumps is 1.5 kW. Compared with the technical solution of using 12 metering pumps with a rated displacement of 5 liters / hour and a rated pressure of 20 MPa (with a single metering pump with a rated power of 0.37 kW and a total rated power of 4.44 kW), 2.94 kW of electricity can be saved, that is, the power saving efficiency of the platform gas well dosing system is as high as more than 66%. Therefore, the power saving effect of the technical solution of the present invention is extremely significant.

[0226] The production test comparative example of this embodiment:

[0227] like Figure 4 As shown, in order to solve the freezing and blocking problem of 2 to 50 natural gas high-pressure injection pipelines belonging to the gas distribution valve group of Sebei Gas Field, the applicant of the present invention conducted a production test in which one metering pump was used to simultaneously inject a control agent into 2 to 10 gas injection pipelines in the gas distribution valve group of Sebei Gas Field from December 2019 to April 2020; taking the production test of one metering pump injecting a control agent into two gas injection pipes at the same time as an example, the technical solution of the production test can be briefly described as follows:

[0228] (1) In order to prevent the formation of hydrate blockage in the gas injection pipeline 406 and the gas injection pipeline 409, a metering pump 402 with a rated displacement of 60 liters / hour and a rated pressure of 20 MPa is used to inject a control agent into the gas injection pipeline 406 and the gas injection pipeline 409 to prevent freezing and unblocking. The instantaneous flow rate of the control agent is adjusted according to the constantly changing gas injection volume of the gas injection pipeline 406 and the gas injection pipeline 409 and the different anti-freezing and unblocking requirements.

[0229] (2) The process flow of adding the control agent can be further summarized as follows: the control agent in the control agent storage tank 400 enters the metering pump 402 at an instantaneous flow rate of 30 to 60 liters / day (or 1.25 to 2.5 liters / hour) through the pump inlet pipeline 401, and then the 30 to 60 liters / day (or 1.25 to 2.5 liters / hour) of control agent is distributed to the dosing pipe 405 and the dosing pipe 408 through the manifold 403; and according to the freezing and blockage (or back pressure increase or fluctuation) of the gas injection pipeline 406 and the gas injection pipeline 409, the needle valve 404 is used to control and adjust the control agent filling flow rate of the dosing pipe 405, and the valve 407 is used to control and adjust the control agent filling flow rate of the dosing pipe 408.

[0230] The results of the production test show that the technical solution has the following major defects:

[0231] (1) The instantaneous displacement of the metering pump 402 (i.e., the instantaneous total flow rate of the control agent in the manifold 403) estimated by adjusting the plunger stroke control dial of the metering pump 402 has an error of up to 15-30% compared with the actual instantaneous dosing flow rate obtained by measuring the liquid level of the control agent storage tank 400.

[0232] (2) Since the control agent storage tank 400 used is a square tank with an effective volume of 1 cubic meter and a cross-sectional area of ​​1 square meter, the tank level drop value corresponding to the dosing flow rate of 30 to 60 liters / day is only 3 to 6 centimeters per hour; therefore, it takes at least more than ten hours to accurately adjust the instantaneous displacement of the metering pump 402.

[0233] (3) Although the instantaneous displacement of the instantaneous metering pump 402 can be accurately confirmed, the operator is still unable to determine the instantaneous flow rate of the control agent in each of the dosing pipes 405 and 408 in actual operation. Therefore, the needle valve 404 cannot be used to control and adjust the control agent injection flow rate of the dosing pipe 405, nor can the valve 407 be used to control and adjust the control agent injection flow rate of the dosing pipe 408; furthermore, the instantaneous flow rate of the control agent required for antifreeze and unblocking of the gas injection pipeline 406 and the gas injection pipeline 409 cannot be controlled.

[0234] (4) The operator can only rely on personal subjective assumptions or visual inspection of the valve stem stroke of valve 404 and valve 407, and rely on personal experience and lessons to estimate the instantaneous flow rate of the control agent entering the gas injection pipeline 406 and gas injection pipeline 409. It is impossible to determine the actual instantaneous flow rate of the control agent in the gas injection pipeline 406 and gas injection pipeline 409 and the degree of flow deviation, and it is impossible to solve the serious flow deviation problem of the control agent. That is, due to the instantaneous displacement of the metering pump 402 (i.e., the manifold 403 The instantaneous total flow rate of the control agent is fixed. When the operator opens the valve 404 and increases the control agent injection flow rate of the dosing pipe 405, the control agent injection flow rate of the dosing pipe 408 will inevitably decrease accordingly. Similarly, when the operator increases the control agent injection flow rate of the dosing pipe 408, the control agent injection flow rate of the dosing pipe 405 will inevitably decrease accordingly. As a result, one of the gas injection pipelines 406 and 409 is frequently frozen and blocked, seriously affecting the production of the gas well.

[0235] As is known in the art, a metering pump is a positive displacement pump, and its displacement does not change with pressure; when its plunger (or diaphragm) stroke is set, its displacement no longer changes.

[0236] (5) In order to reduce the number of freezing and blockage of the gas injection pipeline, the operator generally increases the displacement of the metering pump 402 and significantly increases the dosage of the control agent, so as to increase the actual dosage in the gas injection pipeline 406 and the gas injection pipeline 409; this will inevitably lead to a large amount of control agent not being effectively utilized and wasted, thereby significantly increasing the gas production cost.

[0237] Therefore, the technical solution described in this production test comparative example cannot meet the production requirements of the Sebei gas field.

[0238] It is known from the common knowledge in this field that the gas wells in the Sebei gas field adopt the gas lift production process, and the freezing and blockage of the gas injection pipeline will inevitably seriously affect the production of the gas wells.

[0239] Example 2

[0240] See also Figure 5 As shown, a dosing system includes a container 300, a pump inlet pipe 301, a high-pressure pump 302, a pump outlet tee 303, a reflux pipe 304, a reflux regulating valve 305, a reflux pipe 306, a drug delivery pipe 307, a drug dispensing tee 308, a first dosing pipe 309, a first regulating valve 310, a first metering pipe 311, a first high-pressure micro flowmeter 312, a first drug dispensing pipe 313, a second drug dispensing tee 500, a second dosing pipe 314, a second regulating valve 315, a second metering pipe 316, a second high-pressure micro flowmeter 317, a second drug dispensing pipe 501, a third dosing pipe 502, a third regulating valve 503, a third metering pipe 504, and a third high-pressure micro flowmeter 505;

[0241] The lower portion of the container 300 is connected to one end of a pump inlet pipe 301, and the other end of the pump inlet pipe 301 is connected to the inlet of a high-pressure pump 302.

[0242] The outlet of the high-pressure pump 302 is connected to one end of the pump outlet tee 303;

[0243] The side interface of the pump outlet tee 303 is connected to the inlet of the reflux regulating valve 305 through a reflux pipe 304, and the other end of the pump outlet tee 303 is connected to one end of the drug delivery tube 307;

[0244] The outlet of the reflux regulating valve 305 is connected to the bottom or / and lower part of the container 300 via a reflux pipe 306;

[0245] The other end of the drug delivery tube 307 is connected to one end of the drug dispensing tee 308;

[0246] The side interface of the medicine distributing tee 308 is connected to one end of the first medicine distributing pipe 313, and the other end is connected to one end of the first medicine adding pipe 309;

[0247] The other end of the first dosing tube 309 is connected to the first high-pressure micro flow meter 312 through the first regulating valve 310 and the first metering pipe 311 in sequence;

[0248] The other end of the first medicine distributing pipe 313 is connected to one end of the second medicine distributing tee 500;

[0249] The side interface of the second medicine distributing tee 500 is connected to one end of the second medicine dosing pipe 314, and the other end is connected to one end of the second medicine distributing pipe 501;

[0250] The other end of the second dosing pipe 314 is connected to the second high-pressure micro flow meter 317 through the second regulating valve 315 and the second metering pipe 316 in sequence;

[0251] The other end of the second drug distribution pipe 501 is connected to the third high-pressure micro flow meter 505 through the third drug addition pipe 502, the third regulating valve 503, and the third metering pipe 504 in sequence.

[0252] Example 3

[0253] Repeat Examples 1 and 2, except that:

[0254] The container is any one of a normal pressure container, a pressure container, a cube container, a rectangular parallelepiped container, and a cylindrical container;

[0255] The high-pressure pump is any one of a centrifugal pump, a positive displacement pump, a rotor pump, a reciprocating pump, an electromagnetic pump, a magnetic pump, a gear pump, a metering pump, a membrane pump, and a diaphragm pump;

[0256] The high-pressure micro flowmeter is any one of a high-pressure gear flowmeter, an ultrasonic flowmeter, a high-pressure turbine flowmeter, and a high-pressure metal tube float flowmeter (or a rotor flowmeter), and its measuring range is 5 to 60,000 ml / h;

[0257] The regulating valves are any one of needle valves, stop valves, gate valves, electric valves, solenoid valves, and electric regulating valves;

[0258] The reflux regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve;

[0259] The pipe fittings are any kind of metal pipe fittings;

[0260] All tees are any type of metal tees;

[0261] The drug delivery tube is any one of a metal tube, an aluminum-plastic tube, a steel-plastic tube, a high-pressure hose, a composite tube, and a pipe fitting;

[0262] The dosing pipe is any one of a metal pipe, an aluminum-plastic pipe, a steel-plastic pipe, a high-pressure hose, a composite pipe, and a pipe fitting;

[0263] The medicine dispensing pipe is any one of a metal pipe, an aluminum-plastic pipe, a steel-plastic pipe, a high-pressure hose, a composite pipe, and a pipe fitting;

[0264] The pump inlet pipe is a pipeline and / or pipe fitting made of any material;

[0265] The return pipe is a pipeline and / or pipe fitting made of any material.

[0266] Example 4

[0267] See also Figure 6 As shown, a dosing system includes a container 300, a pump inlet pipe 301, a high-pressure pump 302, a tee 303, a pipe 304, a reflux regulating valve 305, a reflux pipe 306, a drug delivery pipe 600, a regulating valve 310, a pipe 311, and a high-pressure micro flow meter 312;

[0268] The lower portion of the container 300 is connected to one end of a pump inlet pipe 301, and the other end of the pump inlet pipe 301 is connected to the inlet of a high-pressure pump 302.

[0269] The outlet of the high-pressure pump 302 is connected to one end of the tee 303;

[0270] The side interface of the tee 303 is connected to the inlet of the reflux regulating valve 305 through a pipe 304, and the other end of the tee 303 is connected to one end of the drug delivery tube 600;

[0271] The outlet of the reflux regulating valve 305 is connected to the bottom or / and lower part of the container 300 via a reflux pipe 306;

[0272] The other end of the drug delivery tube 600 is connected to the high-pressure micro flow meter 312 through the regulating valve 310 and the pipe 311 in sequence.

[0273] Production test example of this embodiment: Take the Wei 202H82 shale gas platform in Weiyuan, Sichuan as an example. The platform began to apply the technical solution of the present invention to conduct production tests on June 1, 2021. The results showed that since the 6 wells of the platform were gradually put into production over many days, they were not put into production at the same time (that is, the platform initially added drugs to 1 well, and then gradually increased the number of wells to 6); the technical solution of setting a reflux regulating valve at the outlet of the metering pump used in the platform has a very prominent beneficial regulating effect: since the amount of foaming agent (or defoaming agent) required for a single well of the platform is only 0.8 to 1.3 liters / hour; the technical solution of the present invention not only solves the problem of difficulty in purchasing suitable high-pressure, small-displacement metering pumps in the current domestic market, but can use (purchase) a metering pump with a larger displacement to add drugs to 1 gas well; and can meet the actual needs of the platform's 6 gas wells being gradually put into production.

[0274] Example 5

[0275] Example 4 was repeated, except that:

[0276] The container is any one of a normal pressure container, a pressure container, a cube container, a rectangular parallelepiped container, and a cylindrical container;

[0277] The high-pressure pump is any one of a centrifugal pump, a positive displacement pump, a rotor pump, a reciprocating pump, an electromagnetic pump, a magnetic pump, a gear pump, a metering pump, a membrane pump, and a diaphragm pump;

[0278] The high-pressure micro flowmeter is any one of a high-pressure gear flowmeter, an ultrasonic flowmeter, a high-pressure turbine flowmeter, and a high-pressure metal tube float flowmeter (or a rotor flowmeter), and its measuring range is 5 to 60,000 ml / h;

[0279] The regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve;

[0280] The reflux regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve;

[0281] The pipe fitting is any type of metal pipe fitting;

[0282] The tee is any type of metal tee;

[0283] The drug delivery tube is any one of a metal tube, an aluminum-plastic tube, a steel-plastic tube, a high-pressure hose, a composite tube, and a pipe fitting;

[0284] The pump inlet pipe is a pipeline and / or pipe fitting made of any material;

[0285] The return pipe is a pipeline and / or pipe fitting made of any material.

[0286] Example 6

[0287] See also Figure 7 As shown, Example 1 is repeated, with the difference being that: in order to prevent the high-pressure natural gas and / or liquid in the gas well or pipeline from impacting and damaging the high-pressure micro flow meter, a first check valve 700 is provided behind the first high-pressure micro flow meter 312 near one end of the gas well, and the outlet of the first high-pressure micro flow meter 312 is connected to the first check valve 700 through a first check pipe 701; a second check valve 702 is provided behind the second high-pressure micro flow meter 317 near one end of the gas well, and the outlet of the second high-pressure micro flow meter 317 is connected to the second check valve 702 through a second check pipe 703.

[0288] It is known from the common knowledge in this field that a check valve, also known as a one-way valve or a non-return valve, can ensure the one-way flow of a medium (or fluid) and prevent the medium (or fluid) from flowing back; it can be installed horizontally or vertically.

[0289] It is known from the common knowledge in this field that there is currently no public information or successful precedent for using a check valve at the outlet of a metering pump and / or a gas well dosing pipeline; nor is there any public information or successful precedent for using a one-way valve to prevent the backflow of natural gas from a gas well or pipeline from damaging a high-pressure micro flow meter.

[0290] The production test example of this embodiment is to take the Wei 202H82 shale gas platform in Weiyuan, Sichuan as an example.

[0291] The platform has 6 gas wells and began to conduct production tests using the technical solution of the present invention on June 1, 2021. The results show that 12 check valves are set behind the 12 high-pressure micro flow meters on the platform (near one end of the gas well), which can ensure that the high-pressure natural gas and liquid in the annulus of the gas well and the ground pipeline will not flow back and will not impact and damage the high-pressure micro flow meters; during the 15-day continuous injection of foaming agents and defoaming agents in the 6 wells of the platform, the 12 high-pressure micro flow meters equipped with check valves all operated normally and were not damaged.

[0292] Comparative example of the production test of this embodiment: taking the Sulige gas field as an example.

[0293] See also Figure 8As shown, in order to solve the problem of metering and regulating the dosing flow rate of the foaming agent in the gas wells of the Sulige gas field, the applicant of the present invention once conducted a production test of 22 high-pressure micro flow meters in 22 gas wells in the Sulige gas field in May 2021. The technical solution adopted in the production test can be briefly described as follows:

[0294] (1) The foaming agent in the foaming agent tank 800 enters the metering pump 802 through the pump inlet pipe 801, and then passes through the dosing pipeline 803, the regulating valve 310, the pipe fitting 311, the high-pressure micro flow meter 312, the connecting pipe 804, and the casing valve 805 to enter the oil casing annulus of the gas well 806.

[0295] (2) Using a high-pressure micro flow meter 312 with a flow range of 0.06 to 24 liters per hour, the flow rate of the foaming agent entering the gas well 806 (i.e., the displacement of the metering pump 802) is measured.

[0296] (3) Use the plunger stroke control dial of the metering pump 802 to adjust the dosing flow rate of the foaming agent (i.e. the displacement of the metering pump 802).

[0297] The results of this production trial showed that:

[0298] (1) Before the metering pump 802 is started for the first time, the high-pressure micro-flowmeter 312, the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803 must be at normal pressure; after the regulating valve 310 is opened, the high-pressure micro-flowmeter 312, the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803 are still at normal pressure; at the moment the casing valve 805 is opened, the high-pressure natural gas (pressure 3 to 15 MPa) in the oil casing annulus of the gas well 806 must quickly enter the high-pressure micro-flowmeter 312 through the casing valve 805 and the connecting pipe 804, and then quickly enter the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803.

[0299] It is known from the common knowledge in this field that the valve at the outlet of the metering pump 802 can effectively prevent the high-pressure fluid from flowing back into the pump, and the metering pump 802 is a volumetric pump with adjustable displacement, and currently no reflux adjustment is set; therefore, the mature operating procedures of the metering pump 802 clearly stipulate that all valves after the outlet of the metering pump 802 (including but not limited to the regulating valve 310 and the sleeve valve 805) should be opened before the metering pump 802 can be started (otherwise it will cause the metering pump to be blocked).

[0300] (2) The flow range of the high-pressure micro-flowmeter 312 is only 0.06 to 24 liters per hour. The natural gas pressure in the oil casing annulus of gas well 806 is as high as 3 to 15 MPa, and the flow rate and impact force when entering the normal pressure system are extremely high. When the high-pressure natural gas in the oil casing annulus of gas well 806 quickly enters the high-pressure micro-flowmeter 312 in the normal pressure state, its flow rate far exceeds 100 cubic meters per second, which is tens of millions times higher than the maximum flow range of the high-pressure micro-flowmeter 312. Therefore, the high-pressure micro-flowmeter 312 will inevitably be damaged instantly.

[0301] (3) After replacing the damaged high-pressure micro flow meter 312, the production test showed that even if the technical solution of not opening the regulating valve 310 and opening the casing valve 805 very slowly was adopted, the high-pressure natural gas in the oil casing annulus of the gas well 806 would still instantly damage the high-pressure micro flow meter 312.

[0302] (4) After repeated improvements to the operation plan, the technical solution was tested more than ten times in total, and more than 40 high-pressure micro flow meters 312 were damaged. However, the problem of the high-pressure natural gas in the annulus of the oil casing of gas well 806 instantly damaging the high-pressure micro flow meter 312 could not be solved. The production requirements could not be met, and the test had to be terminated and the technical solution was abandoned.

[0303] Example 7

[0304] See also Figure 9 As shown, Examples 1-2 and 6 are repeated, with the difference being that: in order to prevent the backflow of high-pressure natural gas or / and liquid from impacting and damaging the high-pressure micro flowmeter, a first check valve 700 is arranged behind the first high-pressure micro flowmeter 312 near one end of the gas well, and the outlet of the first high-pressure micro flowmeter 312 is connected to the first check valve 700 through a first check pipe fitting 701; a second check valve 702 is arranged behind the second high-pressure micro flowmeter 317 near one end of the gas well, and the outlet of the second high-pressure micro flowmeter 317 is connected to the second check valve 702 through a second check pipe fitting 703; a third check valve 900 is arranged behind the third high-pressure micro flowmeter 505 near one end of the gas well, and the outlet of the third high-pressure micro flowmeter 505 is connected to the third check valve 900 through a third check pipe fitting 901.

[0305] Example 8

[0306] See also Figure 10 As shown, Example 4 is repeated, with the difference being that in order to prevent the backflow of high-pressure natural gas and / or liquid from impacting and damaging the high-pressure micro flow meter, a check valve 1000 is provided behind the high-pressure micro flow meter 312 near one end of the gas well, and the outlet of the high-pressure micro flow meter 312 is connected to the check valve 1000 through a pipe 1001.

[0307] Example 9

[0308] Repeat Examples 1-8, with the difference that: in order to solve the problem of no industrial power supply in gas wells, the power supply of the high-voltage micro flowmeter is any one of dry cells, storage batteries, solar power generation, wind power generation, or any combination of any two or more thereof.

[0309] Example 10

[0310] Repeat Examples 1-8, with the difference being that: in order to solve the problem of unattended gas wells, the flow signal of the high-pressure micro flowmeter is remotely transmitted to a remote location and / or management area, and the power source required for remote transmission of the flow signal is any one of dry cells, storage batteries, solar power generation, and wind power generation, or any combination of any two or more thereof.

[0311] Example 11

[0312] Repeat Examples 1-5, with the difference that: in order to solve the problem of no industrial power supply in the gas well, the high-pressure pump is powered by any one of solar power generation, wind power generation, battery power supply, generator power generation, or any combination of any two or more of them.

[0313] Example 12

[0314] Examples 1-5 and 11 are repeated, with the difference being that, in order to solve the problem of unattended gas wells, the high-pressure pump is started and stopped regularly using a time relay.

[0315] Example 13

[0316] Examples 1-5 were repeated, with the difference being that, in order to solve the problem of unattended gas wells, the high-pressure pump was started and stopped remotely by a remote computer.

[0317] Example 14

[0318] See also Figure 11 As shown, the method for injecting a foaming agent into two gas wells using the dosing system described in Example 1 or 6 includes the following steps:

[0319] 1) Connect the outlet of the first check valve 700 to the first casing valve 1101 of the first gas well 1100 using the first connecting pipe 1102, and connect the outlet of the second check valve 702 to the second casing valve 1105 of the second gas well 1103 using the second connecting pipe 1104;

[0320] 2) First open the first regulating valve 310 and the second regulating valve 315, and then open the first casing valve 1101 and the second casing valve 1105;

[0321] 3) Open the reflux regulating valve 305;

[0322] 4) Start the high pressure pump 302;

[0323] 5) Gradually reduce the opening of the reflux regulating valve 305 so that the instantaneous dosing flow rate of the first high-pressure micro flow meter 312 and / or the second high-pressure micro flow meter 317 is greater than or equal to the dosing flow rate required by the first gas well 1100 and / or the second gas well 1103;

[0324] 6) Adjusting the opening of the first regulating valve 310 according to the instantaneous flow reading of the first high-pressure micro-flowmeter 312 until the instantaneous flow reading of the first high-pressure micro-flowmeter 312 meets the dosing flow requirement of the first gas well 1100;

[0325] 7) According to the instantaneous flow reading of the second high-pressure micro flow meter 317, adjust the opening of the second regulating valve 315 and / or the reflux regulating valve 305 until the instantaneous flow reading of the second high-pressure micro flow meter 317 meets the dosing flow requirement required by the second gas well 1103.

[0326] The production test example of this embodiment is to take the Wei 202H82 shale gas platform in Weiyuan, Sichuan as an example.

[0327] The platform uses a metering pump, a high-pressure micro flow meter, and a check valve. The invention was applied to conduct production tests on June 1, 2021. The results show that:

[0328] (1) Using one metering pump, six high-pressure micro flow meters, and six check valves, it is possible to inject foaming agents into six gas wells at the same time.

[0329] (2) The high-pressure micro flowmeter used has a pressure resistance of 40 MPa and a flow range of 0.06 to 24 liters / hour, which fully meets the production needs of the platform's foaming agent dilution dosing flow rate of 0.8 to 1.3 liters / hour; it can accurately display the instantaneous dosing flow rate and cumulative dosing flow rate of each gas well in the form of a digital display, and can effectively correct the error in the estimated displacement value of the metering pump obtained by relying on the metering pump plunger stroke control dial.

[0330] (3) The adopted reflux regulating valve and high-pressure micro-flowmeter setting scheme has a very prominent beneficial regulating effect: the operator can quickly adjust the dosing flow rate of the foaming agent in each gas well to the dosing flow rate required for the production of each gas well by adjusting the opening of the reflux regulating valve, the first regulating valve, and the second regulating valve a limited number of times according to the instantaneous flow reading of the high-pressure micro-flowmeter.

[0331] (4) The adopted reflux regulating valve setting scheme has another very prominent beneficial regulating effect: it can meet the actual production needs of the platform's six gas wells that are gradually put into production.

[0332] (5) The check valve setting scheme adopted has an extremely outstanding beneficial effect: during the 15-day continuous injection of foaming agent into the six wells of the platform, the six high-pressure micro flow meters used for injecting foaming agent all operated normally and were not damaged.

[0333] (6) The rated power of the metering pump used is 0.75KW. Compared with the technical solution of using six metering pumps with a rated displacement of 5 liters / hour and a rated pressure of 20 MPa (with a single metering pump rated power of 0.37KW and a total rated power of 2.22KW) to add the foaming agent, it can save 1.47KW of electricity. That is, the energy-saving efficiency of the technical solution of the present invention is as high as more than 66%, and the energy-saving effect is extremely significant.

[0334] Example 15

[0335] See also Figure 12 As shown, the method for injecting a foaming agent into three gas wells using the dosing system described in Example 2 or 7 includes the following steps:

[0336] 1) Connect the outlet of the first check valve 700 to the first casing valve 1101 of the first gas well 1100 using a first connecting pipe 1102, connect the outlet of the second check valve 702 to the second casing valve 1105 of the second gas well 1103 using a second connecting pipe 1104, and connect the outlet of the third check valve 900 to the third casing valve 1202 of the third gas well 1200 using a third connecting pipe 1201;

[0337] 2) First open the first regulating valve 310, the second regulating valve 315, and the third regulating valve 503, and then open the first casing valve 1101, the second casing valve 1105, and the third casing valve 1202;

[0338] 3) Open the reflux regulating valve 305;

[0339] 4) Start the high pressure pump 302;

[0340] 5) Gradually reduce the opening of the reflux regulating valve 305 so that the instantaneous dosing flow rate of the first high-pressure micro flowmeter 312 or / and the second high-pressure micro flowmeter 317 or / and the third high-pressure micro flowmeter 505 is greater than or equal to the dosing flow rate required by the first gas well 1100 or / and the second gas well 1103 or / and the third gas well 1200;

[0341] 6) Adjusting the opening of the first regulating valve 310 according to the instantaneous flow reading of the first high-pressure micro-flowmeter 312 until the instantaneous flow reading of the first high-pressure micro-flowmeter 312 meets the dosing flow requirement of the first gas well 1100;

[0342] 7) According to the instantaneous flow reading of the second high-pressure micro flow meter 317, adjust the opening of the second regulating valve 315 and / or the reflux regulating valve 305 until the instantaneous flow reading of the second high-pressure micro flow meter 317 meets the dosing flow requirement of the second gas well 1103;

[0343] 8) According to the instantaneous flow reading of the third high-pressure micro flow meter 505, adjust the opening of the third regulating valve 503 and / or the reflux regulating valve 305 until the instantaneous flow reading of the third high-pressure micro flow meter 505 meets the dosing flow requirement required by the third gas well 1200.

[0344] Example 16

[0345] See also Figure 13 As shown, a method for injecting a foaming agent into a gas well using the dosing system described in Example 4 or 8 includes the following steps:

[0346] 1) Use the connecting pipe 1301 to connect the outlet of the check valve 1000 to the casing valve 1302 of the gas well 1300;

[0347] 2) First open the regulating valve 310, then open the casing valve 1302;

[0348] 3) Open the reflux regulating valve 305;

[0349] 4) Start the high pressure pump 302;

[0350] 5) Adjust the opening of the regulating valve 310 and / or the reflux regulating valve 305 until the instantaneous dosing flow reading of the high-pressure micro flow meter 312 meets the dosing flow requirement of the gas well 1300.

[0351] The production test example of this embodiment is to take the Wei 202H82 shale gas platform in Weiyuan, Sichuan as an example.

[0352] The platform has 6 gas wells and started production tests using the technical solution of the present invention on June 1, 2021. The results show that 12 check valves are installed behind the 12 high-pressure micro flow meters on the platform, which can ensure that the high-pressure natural gas and liquid in the annulus of the gas wells and the ground pipelines will not flow back and will not impact and damage the high-pressure micro flow meters; during the 15-day continuous injection of foaming agents and defoaming agents in the 6 wells of the platform, the 12 high-pressure micro flow meters equipped with check valves all operated normally and were not damaged.

[0353] Comparative example of the production test of this embodiment: taking the Sulige gas field as an example.

[0354] See also Figure 8 As shown, in order to solve the problem of metering and regulating the dosing flow rate of the foaming agent in the gas wells of the Sulige gas field, the applicant of the present invention once conducted a production test of 22 high-pressure micro flow meters in 22 gas wells in the Sulige gas field in May 2021. The technical solution adopted in the production test can be briefly described as follows:

[0355] (1) The foaming agent in the foaming agent tank 800 enters the metering pump 802 through the pump inlet pipe 801, and then passes through the dosing pipeline 803, the regulating valve 310, the pipe fitting 311, the high-pressure micro flow meter 312, the connecting pipe 804, and the casing valve 805 to enter the oil casing annulus of the gas well 806.

[0356] (2) Using a high-pressure micro flow meter 312 with a flow range of 0.06 to 24 liters per hour, the flow rate of the foaming agent entering the gas well 806 (i.e., the displacement of the metering pump 802) is measured.

[0357] (3) Use the plunger stroke control dial of the metering pump 802 to adjust the dosing flow rate of the foaming agent (i.e. the displacement of the metering pump 802).

[0358] The results of this production trial showed that:

[0359] (1) Before the metering pump 802 is started for the first time, the high-pressure micro-flowmeter 312, the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803 must be at normal pressure; after the regulating valve 310 is opened, the high-pressure micro-flowmeter 312, the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803 are still at normal pressure; at the moment the casing valve 805 is opened, the high-pressure natural gas (pressure 3 to 15 MPa) in the oil casing annulus of the gas well 806 must quickly enter the high-pressure micro-flowmeter 312 through the casing valve 805 and the connecting pipe 804, and then quickly enter the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803.

[0360] It is known from the common knowledge in this field that the valve at the outlet of the metering pump 802 can effectively prevent the high-pressure fluid from flowing back into the pump, and the metering pump 802 is a volumetric pump with adjustable displacement, and currently no reflux adjustment is set; therefore, the mature operating procedures of the metering pump 802 clearly stipulate that all valves after the outlet of the metering pump 802 (including but not limited to the regulating valve 310 and the sleeve valve 805) should be opened before the metering pump 802 can be started (otherwise it will cause the metering pump to be blocked).

[0361] (2) The flow range of the high-pressure micro-flowmeter 312 is only 0.06 to 24 liters per hour. The natural gas pressure in the oil casing annulus of gas well 806 is as high as 3 to 15 MPa, and the flow rate and impact force when entering the normal pressure system are extremely high. When the high-pressure natural gas in the oil casing annulus of gas well 806 quickly enters the high-pressure micro-flowmeter 312 in the normal pressure state, its flow rate far exceeds 100 cubic meters per second, which is tens of millions times higher than the maximum flow range of the high-pressure micro-flowmeter 312. Therefore, the high-pressure micro-flowmeter 312 will inevitably be damaged instantly.

[0362] (3) After replacing the damaged high-pressure micro flow meter 312, the production test showed that even if the technical solution of not opening the regulating valve 310 and opening the casing valve 805 very slowly was adopted, the high-pressure natural gas in the oil casing annulus of the gas well 806 would still instantly damage the high-pressure micro flow meter 312.

[0363] (4) After repeated improvements to the operation plan, the technical solution was tested more than ten times in total, and more than 40 high-pressure micro flow meters 312 were damaged. However, the problem of the high-pressure natural gas in the annulus of the oil casing of gas well 806 instantly damaging the high-pressure micro flow meter 312 could not be solved. The production requirements could not be met, and the test had to be terminated and the technical solution was abandoned.

[0364] Example 17

[0365] See also Figure 14 As shown, a method for injecting defoaming agent into the surface pipelines of two gas wells using the dosing system described in Example 1 or 6 includes the following steps:

[0366] 1) A first valve 1402 is installed on the first surface pipeline 1401 of the first gas well 1400, and a second valve 1407 is installed on the second surface pipeline 1405 of the second gas well 1404;

[0367] 2) Connect the outlet of the first check valve 700 to the first valve 1402 using the first connecting pipe 1403, and connect the outlet of the second check valve 702 to the second valve 1407 using the second connecting pipe 1406;

[0368] 3) First open the first regulating valve 310 and the second regulating valve 315, and then open the first valve 1402 and the second valve 1407;

[0369] 4) Open the reflux regulating valve 305;

[0370] 5) Start the high pressure pump 302;

[0371] 6) Gradually reduce the opening of the reflux regulating valve 305 so that the instantaneous dosing flow rate of the first high-pressure micro flow meter 312 and / or the second high-pressure micro flow meter 317 is greater than or equal to the dosing flow rate required by the first gas well 1400 and / or the second gas well 1404;

[0372] 7) Adjusting the opening of the first regulating valve 310 according to the instantaneous flow reading of the first high-pressure micro-flowmeter 312 until the instantaneous flow reading of the first high-pressure micro-flowmeter 312 meets the dosing flow requirement of the first gas well 1400;

[0373] 8) According to the instantaneous flow reading of the second high-pressure micro flow meter 317, adjust the opening of the second regulating valve 315 and / or the reflux regulating valve 305 until the instantaneous flow reading of the second high-pressure micro flow meter 317 meets the dosing flow requirement required by the second gas well 1404.

[0374] The production test example of this embodiment is to take the Wei 202H82 shale gas platform in Weiyuan, Sichuan as an example.

[0375] The platform uses a metering pump, a high-pressure micro flow meter, and a check valve. The invention was applied to conduct production tests on June 1, 2021. The results show that:

[0376] (1) Using one metering pump, six high-pressure micro flow meters, and six check valves, defoaming agent can be injected into six gas wells at the same time.

[0377] (2) The high-pressure micro flowmeter used has a pressure resistance of 40 MPa and a flow range of 0.06 to 24 liters / hour, which fully meets the production needs of the platform for the defoaming agent dilution liquid dosing flow of 0.8 to 1.3 liters / hour for each gas well; it can accurately display the instantaneous dosing flow and cumulative dosing flow of each gas well's surface pipeline in the form of a digital display, and can effectively correct the error in the estimated displacement value of the metering pump obtained by relying on the metering pump plunger stroke control dial.

[0378] (3) The reflux regulating valve and high-pressure micro-flowmeter setting scheme adopted has a very prominent beneficial regulating effect: the operator can quickly adjust the defoaming agent dosing flow rate to the dosing flow rate required for the surface pipeline production of each gas well by adjusting the opening of the reflux regulating valve, the first regulating valve, and the second regulating valve a limited number of times based on the instantaneous flow reading of the high-pressure micro-flowmeter.

[0379] (4) The adopted reflux regulating valve setting scheme has another very prominent beneficial regulating effect: it can meet the actual production needs of the platform's six gas wells that are gradually put into production.

[0380] (5) The adopted check valve setting scheme has an extremely outstanding beneficial effect: during the 15-day continuous injection of defoaming agent into the six wells of the platform, the six high-pressure micro flow meters used for injecting defoaming agent all operated normally and were not damaged.

[0381] (6) The rated power of the metering pump used is 0.75KW. Compared with the technical solution of adding defoaming agent by using 6 metering pumps with a rated displacement of 5 liters / hour and a rated pressure of 20MPa (the rated power of each pump is 0.37KW, and the total rated power is 2.22KW), 1.47KW of electricity can be saved. That is, the energy saving efficiency of the technical solution of the present invention is as high as more than 66%, and the energy saving effect is extremely significant.

[0382] Example 18

[0383] See also Figure 15 As shown, a method for injecting defoaming agent into the surface pipelines of three gas wells using the dosing system described in Example 2 or 7 includes the following steps:

[0384] 1) A first valve 1402 is installed on the first surface pipeline 1401 of the first gas well 1400, a second valve 1407 is installed on the second surface pipeline 1405 of the second gas well 1404, and a third valve 1502 is installed on the third surface pipeline 1501 of the third gas well 1500;

[0385] 2) Connect the outlet of the first check valve 700 to the first valve 1402 using the first connecting pipe 1403, connect the outlet of the second check valve 702 to the second valve 1407 using the second connecting pipe 1406, and connect the outlet of the third check valve 900 to the third valve 1502 using the third connecting pipe 1503;

[0386] 3) First open the first regulating valve 310, the second regulating valve 315, and the third regulating valve 503, and then open the first valve 1402, the second valve 1407, and the third valve 1502;

[0387] 4) Open the reflux regulating valve 305;

[0388] 5) Start the high pressure pump 302;

[0389] 6) Gradually reduce the opening of the reflux regulating valve 305 so that the instantaneous dosing flow rate of the first high-pressure micro flowmeter 312 or / and the second high-pressure micro flowmeter 317 or / and the third high-pressure micro flowmeter 505 is greater than or equal to the dosing flow rate required by the first gas well 1400 or / and the second gas well 1404 or / and the third gas well 1500;

[0390] 7) Adjusting the opening of the first regulating valve 310 according to the instantaneous flow reading of the first high-pressure micro-flowmeter 312 until the instantaneous flow reading of the first high-pressure micro-flowmeter 312 meets the dosing flow requirement of the first gas well 1400;

[0391] 8) Adjust the opening of the second regulating valve 315 and / or the reflux regulating valve 305 according to the instantaneous flow reading of the second high-pressure micro flow meter 317 until the instantaneous flow reading of the second high-pressure micro flow meter 317 meets the dosing flow requirement of the second gas well 1404;

[0392] 9) According to the instantaneous flow reading of the third high-pressure micro flow meter 505, adjust the opening of the third regulating valve 503 and / or the reflux regulating valve 305 until the instantaneous flow reading of the third high-pressure micro flow meter 505 meets the dosing flow requirement required by the third gas well 1500.

[0393] Example 19

[0394] See also Figure 16 As shown, a method for injecting a defoaming agent into a surface pipeline of a gas well using the dosing system described in Example 4 or 8 includes the following steps:

[0395] 1) Installing a valve 1602 on the surface pipeline 1601 of the gas well 1600;

[0396] 2) Connect the outlet of check valve 1000 to valve 1602 using connecting pipe 1603;

[0397] 3) Open regulating valve 310 first, then open valve 1602;

[0398] 4) Open the reflux regulating valve 305;

[0399] 5) Start the high pressure pump 302;

[0400] 6) Adjust the opening of the regulating valve 310 and / or the reflux regulating valve 305 until the instantaneous dosing flow reading of the high-pressure micro flow meter 312 meets the dosing flow requirement of the surface pipeline 1601 of the gas well 1600.

[0401] The production test example of this embodiment is to take the Wei 202H82 shale gas platform in Weiyuan, Sichuan as an example.

[0402] The platform was built on June 1, 2021 and production tests were carried out using the technical solution of the present invention. The results showed that 12 check valves were installed behind the 12 high-pressure micro flow meters on the platform, which can ensure that the high-pressure natural gas and liquid in the annulus of the gas well casing and the ground pipeline will not flow back and will not impact and damage the high-pressure micro flow meters; during the continuous injection of defoaming agents into the 6 wells on the platform for 15 days, the 12 high-pressure micro flow meters equipped with check valves all operated normally and were not damaged.

[0403] Comparative example of the production test of this embodiment: taking the Sulige gas field as an example.

[0404] See also Figure 8 As shown, in order to solve the problem of metering and regulating the dosing flow of foaming agents in gas wells in the Sulige gas field, the applicant of the present invention conducted a production test of 22 high-pressure micro flow meters in 22 gas wells in the Sulige gas field in May 2021. The results of the production test showed that:

[0405] (1) Before the metering pump 802 is started for the first time, the high-pressure micro-flowmeter 312, the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803 must be at normal pressure; after the regulating valve 310 is opened, the high-pressure micro-flowmeter 312, the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803 are still at normal pressure; at the moment the casing valve 805 is opened, the high-pressure natural gas (pressure 3 to 15 MPa) in the oil casing annulus of the gas well 806 must quickly enter the high-pressure micro-flowmeter 312 through the casing valve 805 and the connecting pipe 804, and then quickly enter the pipe fitting 311, the regulating valve 310, and the dosing pipeline 803.

[0406] (2) The flow range of the high-pressure micro-flowmeter 312 is only 0.06 to 24 liters per hour. The natural gas pressure in the oil casing annulus of gas well 806 is as high as 3 to 15 MPa, and the flow rate and impact force when entering the normal pressure system are extremely high. When the high-pressure natural gas in the oil casing annulus of gas well 806 quickly enters the high-pressure micro-flowmeter 312 in the normal pressure state, its flow rate far exceeds 100 cubic meters per second, which is tens of millions times higher than the maximum flow range of the high-pressure micro-flowmeter 312. Therefore, the high-pressure micro-flowmeter 312 will inevitably be damaged instantly.

[0407] (3) After replacing the damaged high-pressure micro flow meter 312, the production test showed that even if the technical solution of not opening the regulating valve 310 and opening the casing valve 805 very slowly was adopted, the high-pressure natural gas in the oil casing annulus of the gas well 806 would still instantly damage the high-pressure micro flow meter 312.

[0408] (4) After repeated improvements to the operation plan, the technical solution was tested more than ten times in total, and more than 40 high-pressure micro flow meters 312 were damaged. However, the problem of the high-pressure natural gas in the annulus of the oil casing of gas well 806 instantly damaging the high-pressure micro flow meter 312 could not be solved. The production requirements could not be met, and the test had to be terminated and the technical solution was abandoned.

[0409] Example 20

[0410] Repeat Examples 14-16, except that the dosing system is used to inject any one of foaming agent, corrosion inhibitor, bactericide, scale inhibitor, corrosion inhibitor and scale inhibitor, or a mixture of any two or more in any proportion, into any number of gas wells among 4 to 50 gas wells.

[0411] Example 21

[0412] Repeat Examples 17-19, except that the dosing system is used to inject any one of defoaming agents, corrosion inhibitors, bactericides, scale inhibitors, or any mixture of any two or more of them in any proportion into any number of 4 to 50 gas pipelines.

[0413] Example 22

[0414] Repeat Examples 17-19, with the difference that: the dosing system is used to inject any one of antifreeze, deblocking agents, prevention and control agents, hydrate inhibitors, antifreeze and deblocking agents, corrosion inhibitors, scale inhibitors, cleaning agents, and functional chemicals, or a mixture of any two or more in any proportion, into any number of 1 to 50 gas injection pipelines.

[0415] Example 23

[0416] Examples 14-16 are repeated, except that the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressant, emulsifier, foaming agent, oil displacement agent, and drag reducer, or a mixture of any two or more in any proportion, into any number of 1 to 50 oil wells.

[0417] Example 24

[0418] Repeat Examples 14-16, except that: the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressant, emulsifier, foaming agent, oil displacing agent, drag reducer, or a mixture of any two or more in any proportion into any number of 1 to 50 injection wells.

[0419] Example 25

[0420] Repeat Examples 17-19, except that: the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressant, emulsifier, foaming agent, oil displacement agent, drag reducer, or a mixture of any two or more in any proportion into any number of 1 to 50 oil production pipelines.

[0421] Example 25

[0422] Repeat Examples 17-19, with the difference that: the dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventive agents, pour point depressants, emulsifiers, foaming agents, oil displacing agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of the 1 to 50 water injection lines.

[0423] The words "up", "down", "left", "right", etc. used in this article to describe the directions are for the convenience of explanation based on the directions shown in the drawings. In the actual system, these directions may be different due to the placement of the system.

[0424] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications based on the above description are possible. It is not possible to enumerate all embodiments here. Any obvious variations or modifications arising from the technical solution of the present invention remain within the scope of protection of the present invention.

Claims

1. A dosing system, characterized in that: It includes a container, a pump inlet pipe, a high-pressure pump, a pump outlet tee, a reflux pipe, a reflux regulating valve, a reflux pipe, a drug delivery pipe, a drug distribution tee, a first drug dosing pipe, a first regulating valve, a first metering pipe, a first high-pressure micro flowmeter, a first drug distribution pipe, a second drug dosing pipe, a second regulating valve, a second metering pipe, and a second high-pressure micro flowmeter; The lower portion of the container is connected to one end of a pump inlet pipe, and the other end of the pump inlet pipe is connected to an inlet of a high-pressure pump; The high-pressure pump outlet is connected to one end of the pump outlet tee; The side interface of the pump outlet tee is connected to the inlet of the reflux regulating valve through a reflux pipe fitting, and the other end of the pump outlet tee is connected to one end of the drug delivery tube; The outlet of the reflux regulating valve is connected to the bottom or / and lower part of the container via a reflux pipe; The other end of the drug delivery tube is connected to one end of the drug dispensing tee; The side interface of the medicine distributing tee is connected to one end of the first medicine distributing pipe, and the other end is connected to one end of the first medicine adding pipe; The other end of the first dosing tube is connected to the first high-pressure micro flow meter through the first regulating valve and the first metering pipe in sequence; The other end of the first medicine distributing pipe is connected to the second high-pressure micro flow meter through the second medicine adding pipe, the second regulating valve and the second metering pipe fitting in sequence.

2. A dosing system according to claim 1, characterized in that: A first check valve is arranged behind the first high-pressure micro flowmeter near one end of the gas well, and the outlet of the first high-pressure micro flowmeter is connected to the first check valve through a first check pipe fitting; a second check valve is arranged behind the second high-pressure micro flowmeter near one end of the gas well, and the outlet of the second high-pressure micro flowmeter is connected to the second check valve through a second check pipe fitting.

3. A dosing system, characterized in that: It includes a container, a pump inlet pipe, a high-pressure pump, a pump outlet tee, a reflux pipe fitting, a reflux regulating valve, a reflux pipe, a drug delivery pipe, a drug distribution tee, a first drug dosing pipe, a first regulating valve, a first metering pipe fitting, a first high-pressure micro flowmeter, a first drug distribution pipe, a second drug distribution tee fitting, a second drug dosing pipe, a second regulating valve, a second metering pipe fitting, a second high-pressure micro flowmeter, a second drug distribution pipe, a third drug dosing pipe, a third regulating valve, a third metering pipe fitting, and a third high-pressure micro flowmeter; The lower portion of the container is connected to one end of a pump inlet pipe, and the other end of the pump inlet pipe is connected to an inlet of a high-pressure pump; The high-pressure pump outlet is connected to one end of the pump outlet tee; The side interface of the pump outlet tee is connected to the inlet of the reflux regulating valve through a reflux pipe fitting, and the other end of the pump outlet tee is connected to one end of the drug delivery tube; The outlet of the reflux regulating valve is connected to the bottom or / and lower part of the container via a reflux pipe; The other end of the drug delivery tube is connected to one end of the drug dispensing tee; The side interface of the medicine distributing tee is connected to one end of the first medicine distributing pipe, and the other end is connected to one end of the first medicine adding pipe; The other end of the first dosing tube is connected to the first high-pressure micro flow meter through the first regulating valve and the first metering pipe in sequence; The other end of the first medicine distributing pipe is connected to one end of the second medicine distributing tee; The side interface of the second medicine distributing tee is connected to one end of the second medicine dosing pipe, and the other end is connected to one end of the second medicine distributing pipe; The other end of the second dosing pipe is connected to the second high-pressure micro flow meter through the second regulating valve and the second metering pipe in sequence; The other end of the second drug distributing pipe is connected to the third high-pressure micro flow meter through the third drug adding pipe, the third regulating valve and the third metering pipe fitting in sequence.

4. A dosing system according to claim 3, characterized in that: A first check valve is arranged behind the first high-pressure miniature flowmeter near one end of the gas well, and the outlet of the first high-pressure miniature flowmeter is connected to the first check valve through a first check pipe fitting; a second check valve is arranged behind the second high-pressure miniature flowmeter near one end of the gas well, and the outlet of the second high-pressure miniature flowmeter is connected to the second check valve through a second check pipe fitting; a third check valve is arranged behind the third high-pressure miniature flowmeter near one end of the gas well, and the outlet of the third high-pressure miniature flowmeter is connected to the third check valve through a third check pipe fitting.

5. A dosing system, characterized in that: Including container, pump inlet pipe, high-pressure pump, tee, pipe fittings, reflux regulating valve, reflux pipe, drug delivery pipe, regulating valve, high-pressure micro flow meter; The lower portion of the container is connected to one end of a pump inlet pipe, and the other end of the pump inlet pipe is connected to an inlet of a high-pressure pump; The high-pressure pump outlet is connected to one end of a tee; The side interface of the three-way is connected to the inlet of the reflux regulating valve through a pipe fitting, and the other end of the three-way is connected to one end of the drug delivery tube; The outlet of the reflux regulating valve is connected to the bottom or / and lower part of the container via a reflux pipe; The other end of the medicine delivery tube is connected to a high-pressure micro flow meter through a regulating valve and a pipe fitting in sequence.

6. A dosing system according to claim 5, characterized in that: A check valve is arranged behind the high-pressure micro flow meter close to one end of the gas well, and the outlet of the high-pressure micro flow meter is connected to the check valve through a pipe fitting.

7. The dosing system according to any one of claims 1, 3, and 5, characterized in that: The container is any one of a normal pressure container, a pressure container, a cube container, a rectangular parallelepiped container, and a cylindrical container; The high-pressure pump is any one of a centrifugal pump, a positive displacement pump, a rotor pump, a reciprocating pump, an electromagnetic pump, a magnetic pump, a gear pump, a metering pump, a membrane pump, and a diaphragm pump; The regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve; The reflux regulating valve is any one of a needle valve, a stop valve, a gate valve, an electric valve, a solenoid valve, and an electric regulating valve; The pipe fitting is any type of metal pipe fitting; The tee is any type of metal tee; The drug delivery tube is any one of a metal tube, an aluminum-plastic tube, a steel-plastic tube, a high-pressure hose, a composite tube, and a pipe fitting; The pump inlet pipe is a pipeline and / or pipe fitting made of any material; The return pipe is a pipeline and / or pipe fitting made of any material.

8. The dosing system according to any one of claims 1 to 6, characterized in that: The high-pressure micro flowmeter is any one of a high-pressure gear flowmeter, an ultrasonic flowmeter, a high-pressure turbine flowmeter, a high-pressure metal tube float flowmeter, and a rotor flowmeter, and its measuring range is 5 to 60,000 ml / h.

9. The dosing system according to any one of claims 1 to 6, characterized in that: The power source of the high-voltage micro flowmeter is any one of dry cell, storage battery, solar power generation, wind power generation or any combination of any two or more thereof.

10. The dosing system according to any one of claims 1 to 6, characterized in that: The flow signal of the high-pressure micro flow meter is remotely transmitted to a remote location and / or management area, and the power source required for remote transmission of the flow signal is any one of dry cells, storage batteries, solar power generation, wind power generation, or any combination of any two or more thereof.

11. The dosing system according to any one of claims 1, 3, and 5, characterized in that: The high-pressure pump is powered by any one of solar power generation, wind power generation, battery power generation, and generator power generation, or any combination of any two or more of them.

12. The dosing system according to any one of claims 1, 3, and 5, characterized in that: The high-pressure pump is started and stopped regularly by a time relay.

13. The dosing system according to any one of claims 1, 3, and 5, characterized in that: The high-pressure pump is started and stopped by remote control of a remote computer.

14. A dosing method according to the dosing system of claim 1, characterized in that: The steps include: 1) Connecting the outlet of the first check valve to the first casing valve of the first gas well using a first connecting pipe fitting, and connecting the outlet of the second check valve to the second casing valve of the second gas well using a second connecting pipe fitting; 2) First open the first regulating valve and the second regulating valve, and then open the first casing valve and the second casing valve; 3) Open the reflux regulating valve; 4) Start the high-pressure pump; 5) Gradually reduce the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well; 6) Adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well; 7) According to the instantaneous flow reading of the second high-pressure micro flow meter, adjust the opening of the second regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the second high-pressure micro flow meter meets the dosing flow requirement of the second gas well.

15. A dosing method according to the dosing system of claim 3, characterized in that: The steps include: 1) Connect the outlet of the first check valve to the first casing valve of the first gas well using a first connecting pipe fitting, connect the outlet of the second check valve to the second casing valve of the second gas well using a second connecting pipe fitting, and connect the outlet of the third check valve to the third casing valve of the third gas well using a third connecting pipe fitting; 2) First open the first regulating valve, the second regulating valve, and the third regulating valve, and then open the first casing valve, the second casing valve, and the third casing valve; 3) Open the reflux regulating valve; 4) Start the high-pressure pump; 5) Gradually reduce the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter or / and the third high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well or / and the third gas well; 6) Adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well; 7) Adjust the opening of the second regulating valve and / or the reflux regulating valve according to the instantaneous flow reading of the second high-pressure micro-flow meter until the instantaneous flow reading of the second high-pressure micro-flow meter meets the dosing flow requirement of the second gas well; 8) According to the instantaneous flow reading of the third high-pressure micro flow meter, adjust the opening of the third regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the third high-pressure micro flow meter meets the dosing flow requirement of the third gas well.

16. A dosing method according to the dosing system of claim 5, characterized in that: The steps include: 1) Use connecting pipe fittings to connect the check valve outlet to the casing valve of the gas well; 2) Open the regulating valve first, then open the casing valve; 3) Open the reflux regulating valve; 4) Start the high-pressure pump; 5) Adjust the opening of the regulating valve and / or the reflux regulating valve until the instantaneous dosing flow reading of the high-pressure micro flow meter meets the dosing flow requirement of the gas well.

17. A dosing method according to the dosing system of claim 1, characterized in that: The steps include: 1) Installing a first valve on a first surface pipeline of a first gas well, and installing a second valve on a second surface pipeline of a second gas well; 2) Connecting the outlet of the first check valve to the first valve with a first connecting pipe, and connecting the outlet of the second check valve to the second valve with a second connecting pipe; 3) First open the first regulating valve and the second regulating valve, and then open the first valve and the second valve; 4) Open the reflux regulating valve; 5) Start the high-pressure pump; 6) Gradually reduce the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well; 7) Adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well; 8) According to the instantaneous flow reading of the second high-pressure micro flow meter, adjust the opening of the second regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the second high-pressure micro flow meter meets the dosing flow requirement of the second gas well.

18. A dosing method according to the dosing system of claim 3, characterized in that: The steps include: 1) Installing a first valve on a first surface pipeline of a first gas well, installing a second valve on a second surface pipeline of a second gas well, and installing a third valve on a third surface pipeline of a third gas well; 2) Connect the outlet of the first check valve to the first valve using a first connecting pipe, connect the outlet of the second check valve to the second valve using a second connecting pipe, and connect the outlet of the third check valve to the third valve using a third connecting pipe; 3) First open the first regulating valve, the second regulating valve, and the third regulating valve, and then open the first valve, the second valve, and the third valve; 4) Open the reflux regulating valve; 5) Start the high-pressure pump; 6) Gradually reduce the opening of the reflux regulating valve so that the instantaneous dosing flow rate of the first high-pressure micro flow meter or / and the second high-pressure micro flow meter or / and the third high-pressure micro flow meter is greater than or equal to the dosing flow rate required by the first gas well or / and the second gas well or / and the third gas well; 7) Adjusting the opening of the first regulating valve according to the instantaneous flow reading of the first high-pressure micro-flow meter until the instantaneous flow reading of the first high-pressure micro-flow meter meets the dosing flow requirement of the first gas well; 8) Adjust the opening of the second regulating valve and / or the reflux regulating valve according to the instantaneous flow reading of the second high-pressure micro-flow meter until the instantaneous flow reading of the second high-pressure micro-flow meter meets the dosing flow requirement of the second gas well; 9) According to the instantaneous flow reading of the third high-pressure micro flow meter, adjust the opening of the third regulating valve and / or the reflux regulating valve until the instantaneous flow reading of the third high-pressure micro flow meter meets the dosing flow requirement of the third gas well.

19. A dosing method according to the dosing system of claim 5, characterized in that: The steps include: 1) Install valves on the surface pipeline of the gas well; 2) Use the connecting pipe to connect the check valve outlet to the valve; 3) Open the regulating valve first, then open the valve; 4) Open the reflux regulating valve; 5) Start the high-pressure pump; 6) Adjust the opening of the regulating valve and / or the reflux regulating valve until the instantaneous dosing flow reading of the high-pressure micro flow meter meets the dosing flow requirement of the gas well surface pipeline.

20. The dosing method of any one of claims 14-16, characterized in that: The dosing system is used for injecting foaming agent into any number of gas wells among 4 to 50 gas wells.

21. The dosing method of any one of claims 14-16, characterized in that: The dosing system is used to inject any one of corrosion inhibitors, bactericides, scale inhibitors, or a mixture of any two or more of the corrosion inhibitors and scale inhibitors in any proportion into any number of gas wells among 1 to 50 gas wells.

22. The dosing method of any one of claims 14-16, characterized in that: The dosing system is used to inject any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, into any number of 1 to 50 oil wells or / and water injection wells.

23. The dosing method of any one of claims 17 to 19, characterized in that: The dosing system is used to inject defoaming agent into any number of 4 to 50 gas production pipelines.

24. The dosing method of any one of claims 17 to 19, characterized in that: The dosing system is used to inject any one of corrosion inhibitors, bactericides, scale inhibitors, or a mixture of any two or more of the corrosion inhibitors and scale inhibitors in any proportion into any number of 1 to 50 gas pipelines.

25. The dosing method of any one of claims 17-19, characterized in that: The dosing system is used to inject any one of antifreeze, deblocking agents, prevention and control agents, hydrate inhibitors, antifreeze and deblocking agents, corrosion inhibitors, scale inhibitors, cleaning agents, and functional chemicals, or a mixture of any two or more in any proportion, into any number of 1 to 50 gas injection pipelines.

26. The dosing method of any one of claims 17-19, characterized in that: The dosing system is used to add any one of corrosion inhibitors, scale inhibitors, bactericides, viscosity reducers, paraffin removers, paraffin remover and preventer, pour point depressants, emulsifiers, foaming agents, oil displacement agents, and drag reducers, or a mixture of any two or more in any proportion, to any number of 1 to 50 oil production pipelines or / and water injection pipelines.

Images