Automatic control method and device for filling corrosion inhibitor

Abstract

The invention discloses an automatic control method and device for corrosion inhibitor filling, and relates to the technical field of corrosion protection of petroleum and natural gas development. According to the technical scheme, a gas production pipeline is sequentially connected with a corrosion inhibitor injection pipeline, a natural gas flowmeter, a pressure transmitter and a gas component analyzer in the gas outlet direction, and a corrosion inhibitor injection metering pump is arranged on the corrosion inhibitor injection pipeline; and the corrosion inhibitor injection pipeline, the natural gas flowmeter, the pressure transmitter, the gas component analyzer and the corrosion inhibitor injection metering pump are respectively connected with the PLC calculation and control device. The automatic control method and device for corrosion inhibitor filling have the beneficial effects that timely, accurate and automatic control over corrosion inhibitor filling is achieved, the requirement for corrosion control is met, economical efficiency and reasonability are improved, and powerful technical guarantee is provided for gas production of a natural gas field or a gas storage.

Description

Technical Field

[0001] The present invention relates to the technical field of corrosion protection in the development of petroleum and natural gas, and more specifically to an automatic control method and device for adding corrosion inhibitor. Background Art

[0002] The wet natural gas produced from natural gas fields or gas storages may contain CO2 acidic gas. When CO2 reaches a certain partial pressure, it will cause a certain degree of internal corrosion to gas production pipelines and equipment, which not only poses a safety hazard, but may also threaten gas production and natural gas supply. According to the requirements for corrosion and its control in Chapter 7 of the "Design Code for Natural Gas Dehydration" SY / T 0076-2023: "7.0.2 For wet natural gas with a carbon dioxide partial pressure greater than or equal to 0.021MPa, and when it causes electrochemical corrosion, anti-corrosion measures should be taken for equipment." "7.0.32 When the carbon dioxide partial pressure is between 0.021MPa and 0.21MPa, corrosion control measures should be taken. 3 When the carbon dioxide partial pressure is greater than 0.21MPa, corrosion control measures should be adopted. 4 Corrosion control measures should be taken to control the pH value of the glycol-rich solution, inject corrosion inhibitors, increase the corrosion margin, or use corrosion-resistant materials." For the built gas production and processing system, injecting corrosion inhibitors is the most economical and feasible corrosion control measure. For example, a Chinese patent with publication number CN103194758B discloses a corrosion inhibitor slug pre-filming device for a gas production pipeline. By controlling the pressure difference at both ends of the corrosion inhibitor slug and then controlling the gas running speed, the corrosion inhibitor forms a slug flow in the pipeline, thereby pre-filming the pipeline with the corrosion inhibitor.

[0003] In actual gas production, the volume molar content of CO2 is measured by obtaining a natural gas sample and calculating its partial pressure. After the corrosion inhibitor filling conditions are met, the corrosion inhibitor injection pump is started to add corrosion inhibitor to the gas production system. Therefore, the corrosion inhibitor filling is prone to lag, and the filling amount cannot be adjusted in time with the change of gas production, making it difficult to achieve accurate filling. Either the amount of corrosion inhibitor added is insufficient to meet the corrosion protection needs; or the amount added is too large, resulting in a waste of corrosion inhibitor and uneconomical. Summary of the invention

[0004] In order to solve the technical problems existing in the above-mentioned prior art, the present invention provides an automatic control method and device for corrosion inhibitor filling, which can make the corrosion inhibitor filling in the gas production process of natural gas fields or gas storage reservoirs more timely, accurate and automatically controlled, which can not only meet the corrosion control needs, but also make the corrosion inhibitor filling more economical and reasonable.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] An automatic control device for adding corrosion inhibitors, wherein a corrosion inhibitor injection pipeline, a natural gas flow meter, a pressure transmitter, and a gas-gas component analyzer are sequentially connected to a gas production pipeline along a gas outlet direction; a corrosion inhibitor injection pipeline is provided with a corrosion inhibitor filling metering pump; and the corrosion inhibitor injection pipeline, the natural gas flow meter, the pressure transmitter, the gas-gas component analyzer, and the corrosion inhibitor filling metering pump are respectively connected to a PLC calculation and control device.

[0007] Furthermore, a corrosion inhibitor filling port is provided on the gas production pipeline, and the corrosion inhibitor injection pipeline is connected to the corrosion inhibitor filling port.

[0008] Furthermore, the corrosion inhibitor filling metering pump, the natural gas flow meter, the pressure transmitter, and the gas composition analyzer are connected to the PLC calculation and control device through communication cables respectively.

[0009] Furthermore, a stop valve is provided on the corrosion inhibitor injection pipeline.

[0010] Furthermore, the pipelines of the pressure transmitter and the gas composition analyzer are respectively provided with stop valves.

[0011] The present invention also includes an automatic control method for adding corrosion inhibitor, the steps are as follows:

[0012] S1. The gas quality component analyzer performs online gas quality component analysis on the produced gas, the pressure transmitter collects the pressure of the produced gas, and the natural gas flow meter collects the instantaneous flow of the produced gas;

[0013] S2, input the gas quality component analysis results, produced gas pressure and instantaneous flow rate into the PLC calculation and control device;

[0014] S3. The PLC calculation and control device obtains the CO2 partial pressure by multiplying the CO2 volume molar percentage content and the produced gas pressure in the gas composition analysis results; and determines whether it is necessary to add corrosion inhibitor to the gas production system based on the CO2 partial pressure value.

[0015] Furthermore, in step S3, if the CO2 partial pressure value is less than 0.021MPa, the gas production system does not need to be filled with corrosion inhibitor; if the CO2 partial pressure value is greater than or equal to 0.021MPa, the PLC calculation and control device sends a pump start command to the corrosion inhibitor filling metering pump to add corrosion inhibitor to the gas production system.

[0016] Further, in step S3, when the calculated CO2 partial pressure value is between 0.021MPa and 0.21MPa, the PLC calculation and control device determines it as mild corrosion, and the corrosion inhibitor is added at 0.3L / 10 4 m 3 -0.4L / 10 4 m 3Combined with the recorded instantaneous flow value of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow of produced gas, and sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump based on the calculation result.

[0017] Furthermore, in step S3, when the calculated CO2 partial pressure value is greater than 0.21 MPa, the PLC calculation and control device determines it as moderate to severe corrosion, and the corrosion inhibitor is added at 0.6 L / 10 4 m 3 -0.7L / 10 4 m 3 Combined with the recorded instantaneous flow rate of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow rate of produced gas, and sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump based on the calculation result.

[0018] Furthermore, the PLC calculation and control device sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump through the communication cable according to the calculation result.

[0019] Beneficial effects of the present invention:

[0020] Compared with the prior art, the automatic control method and device for adding corrosion inhibitor of the present invention has the following technical characteristics or beneficial effects:

[0021] (1) Improved timeliness and accuracy: Through online gas quality component analysis, pressure monitoring and flow measurement, the present invention can obtain the CO2 partial pressure information in natural gas in real time, and judge whether corrosion inhibitor needs to be added and the amount of addition based on this. This real-time feedback mechanism significantly improves the timeliness and accuracy of corrosion inhibitor addition, ensuring that corrosion control measures can quickly respond to changes in natural gas composition and effectively prevent the occurrence of corrosion problems.

[0022] (2) Economic and rational optimization: According to different intervals of CO2 partial pressure, the present invention automatically adjusts the injection amount of corrosion inhibitor, avoiding the problem of insufficient or excessive injection due to hysteresis in traditional methods. This on-demand injection strategy not only meets the needs of corrosion control, but also minimizes the waste of corrosion inhibitor, improves resource utilization efficiency, and reduces operating costs.

[0023] (3) High degree of automation: The present invention realizes automatic control of corrosion inhibitor filling through PLC calculation and control device, and can complete the whole process from data collection, analysis and judgment to filling instruction issuance without human intervention. This not only improves work efficiency, but also reduces errors and safety hazards caused by human operation.

[0024] (4) Strong adaptability: The device and method of the present invention are applicable to natural gas fields or gas storages of different sizes, and can flexibly cope with various complex geological and climatic conditions. At the same time, by adjusting the parameter settings in the PLC program, it can also easily adapt to different corrosion control standards and requirements.

[0025] (5) Easy maintenance and management: Due to the modular design and standardized interface, the device of the present invention is easy to install, debug and maintain. In addition, the PLC calculation and control device also has data storage and remote monitoring functions, which is convenient for management personnel to monitor and analyze the corrosion inhibitor filling process in real time, providing strong support for optimizing corrosion control measures.

[0026] In summary, the present invention provides an automatic control method and device for corrosion inhibitor filling, thereby achieving timely, accurate and automatic control of corrosion inhibitor filling, which not only meets the needs of corrosion control, but also improves economy and rationality, and provides a strong technical guarantee for gas production in natural gas fields or gas storages. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below in combination with the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0028] Figure 1 It is a connection schematic diagram of the automatic control device for adding corrosion inhibitor of the present invention;

[0029] The reference numerals in the figure are: 1-extracted wet gas, 2-gas production pipeline, 3-corrosion inhibitor injection pipeline, 4-communication cable, 5-corrosion inhibitor filling port, 6-natural gas flow meter, 7-pressure transmitter, 8-gas composition analyzer, 9-PLC calculation and control device, 10-corrosion inhibitor filling metering pump. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Figure 1 The automatic control method and device for adding corrosion inhibitors are further explained, and the technical solutions in the embodiments of the present application are clearly and completely described; obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments, and all other embodiments obtained by ordinary technicians in this field without making creative work based on the embodiments in the present application are within the scope of protection of the present application.

[0031] Example 1

[0032] An automatic control device for adding corrosion inhibitor, wherein a corrosion inhibitor injection pipeline 3, a natural gas flow meter 6, a pressure transmitter 7, and a gas quality component analyzer 8 are sequentially connected to a gas production pipeline 2 along a gas outlet direction, wherein the corrosion inhibitor injection pipeline 3 is provided with a corrosion inhibitor injection metering pump 10, and the corrosion inhibitor injection pipeline 3, the natural gas flow meter 6, the pressure transmitter 7, the gas quality component analyzer 8, and the corrosion inhibitor injection metering pump 10 are respectively connected to a PLC calculation and control device 9. A corrosion inhibitor filling port 5 is provided on the gas production pipeline 2, and the corrosion inhibitor injection pipeline 3 is connected to the corrosion inhibitor filling port 5. The corrosion inhibitor filling metering pump 10, the natural gas flow meter 6, the pressure transmitter 7, and the gas quality component analyzer 8 are respectively connected to the PLC calculation and control device 9 through a communication cable 4.

[0033] Preferably, a stop valve is provided on the corrosion inhibitor injection pipeline 3, and stop valves are respectively provided on the pipelines of the pressure transmitter 7 and the gas composition analyzer 8.

[0034] In the gas production process of a natural gas field or a gas storage, a gas quality component analyzer 8, a pressure transmitter 7, a natural gas flow meter 6, a PLC calculation and control device 9 and a corrosion inhibitor filling metering pump 10 are sequentially arranged.

[0035] During the gas production process, the gas quality component analyzer 8 performs online gas quality component analysis on the produced gas, the pressure transmitter 7 collects the pressure (MPa) of the produced gas, and the natural gas flow meter 6 collects the instantaneous flow rate (10 4 m 3 / second), and automatically input the gas quality component analysis results, produced gas pressure and instantaneous flow rate into the PLC calculation and control device 9 through the communication cable. The PLC calculation and control device 9 obtains the CO2 partial pressure by multiplying the CO2 volume molar percentage content and the produced gas pressure in the gas quality component analysis results. If the CO2 partial pressure value is less than 0.021MPa, the gas production system does not need to be filled with corrosion inhibitor; if the CO2 partial pressure value is greater than or equal to 0.021MPa, the PLC calculation and control device sends a pump start command to the corrosion inhibitor filling metering pump through the communication cable 4 to fill the gas production system with corrosion inhibitor.

[0036] According to the calculated CO2 partial pressure value, the instantaneous amount of corrosion inhibitor added is divided into two levels: (1) When the calculated CO2 partial pressure value is between 0.021MPa (inclusive) and 0.21MPa (inclusive), the PLC calculation and control device determines it as mild corrosion, and the amount of corrosion inhibitor added is the recommended empirical value of 0.38L / 10 4 m 3, combined with the recorded instantaneous flow rate of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow rate of produced gas, and sends an instantaneous amount of corrosion inhibitor added instruction to the corrosion inhibitor filling metering pump through the communication cable according to the calculation result; (2) When the calculated CO2 partial pressure value is greater than 0.21MPa, the PLC calculation and control device judges it as moderate to severe corrosion, and the amount of corrosion inhibitor added is the recommended empirical value of 0.66L / 10 4 m 3 Combined with the recorded instantaneous flow rate of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow rate of produced gas, and sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump through the communication cable based on the calculation result.

[0037] During gas production operations, the PLC calculation and control device executes the above-mentioned data collection, process calculation, and logical judgment at any time, and issues control adjustment instructions, thereby realizing the automatic and precise control function of corrosion inhibitor filling.

[0038] Example 2

[0039] This embodiment combines the attached Figure 1 Describing an embodiment:

[0040] Combination Figure 1 In the gas production process of the natural gas field or gas storage, a gas quality component analyzer 8, a pressure transmitter 7, a natural gas flow meter 6, a PLC calculation and control device 9 and a corrosion inhibitor filling metering pump 10 are sequentially arranged.

[0041] During the gas production process, the gas quality component analyzer 8 performs online gas quality component analysis on the produced gas, the pressure transmitter 7 collects the pressure (MPa) of the produced gas, and the natural gas flow meter 6 collects the instantaneous flow rate (10 4 m 3 / second), and the gas quality component analysis results, produced gas pressure and instantaneous flow rate are automatically input into the PLC calculation and control device 9 through the communication cable. The PLC calculation and control device 9 multiplies the CO2 volume molar percentage and the produced gas pressure in the collected gas quality component analysis results to obtain the CO2 partial pressure value. If the CO2 partial pressure value is less than 0.021MPa, according to the specification requirements, the gas production system does not need to be filled with corrosion inhibitor; if the CO2 partial pressure value is greater than or equal to 0.021MPa, the PLC calculation and control device 9 will send a pump start command to the corrosion inhibitor filling metering pump to fill the gas production system with corrosion inhibitor.

[0042] According to the calculated CO2 partial pressure value, the instantaneous amount of corrosion inhibitor added is divided into two levels: (1) When the calculated CO2 partial pressure value is between 0.021MPa (inclusive) and 0.21MPa (inclusive), the PLC calculation and control device 9 determines it as mild corrosion, and the amount of corrosion inhibitor added is the recommended empirical value of 0.38L / 10 4 m 3 , combined with the recorded instantaneous flow value of produced gas, the PLC calculation and control device 9 automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow value of produced gas, and sends an instantaneous amount of corrosion inhibitor added instruction to the corrosion inhibitor filling metering pump through the communication cable according to the calculation result; (2) When the calculated CO2 partial pressure value is greater than 0.21MPa, the PLC calculation and control device judges it as moderate to severe corrosion, and the amount of corrosion inhibitor added takes the recommended empirical value of 0.66L / 10 4 m 3 Combined with the recorded instantaneous flow value of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow value of produced gas, and sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump through the communication cable according to the calculation result.

[0043] During gas production operations, the PLC calculation and control device will execute the above-mentioned data collection, process calculation, and logical judgment at any time, and issue control adjustment instructions, thereby realizing the automatic and precise control function of corrosion inhibitor filling.

[0044] The present invention has the functions of data collection, process calculation, logical judgment and control adjustment, and can automatically collect real-time data such as gas quality components, gas pressure and instantaneous flow rate of produced gas. The PLC calculation and control device can automatically calculate the CO2 partial pressure and judge the degree of CO2 corrosion according to the CO2 partial pressure. Then, the instantaneous injection amount of corrosion inhibitor corresponding to mild corrosion and moderate and severe corrosion is calculated respectively from the instantaneous amount of produced gas, and the PLC calculation and control device sends a control instruction to the corrosion inhibitor injection metering pump, thereby realizing automatic and accurate injection control of corrosion inhibitor in the gas production system.

[0045] Example 3

[0046] This embodiment provides an automatic control method for adding corrosion inhibitors. During the gas production process, the gas quality component analyzer automatically performs online gas quality component analysis on the produced gas, the pressure transmitter collects the pressure (MPa) of the produced gas, and the natural gas flow meter collects the instantaneous flow rate (10 4 m 3 / Second).

[0047] The gas composition analysis results, produced gas pressure value and instantaneous flow value are automatically input into the PLC calculation and control device through the communication cable. The PLC calculation and control device multiplies the CO2 volume molar percentage content and the produced gas pressure value in the gas composition analysis results to obtain the CO2 partial pressure value.

[0048] If the CO2 partial pressure value is less than 0.021MPa, the PLC calculation and control device will determine that the gas production system does not need to be filled with corrosion inhibitor; if the CO2 partial pressure value is greater than or equal to 0.021MPa, the PLC calculation and control device will determine that the gas production system needs to be filled with corrosion inhibitor. The PLC calculation and control device sends a pump start command to the corrosion inhibitor filling metering pump through the communication cable to add corrosion inhibitor to the gas production system.

[0049] According to the calculated CO2 partial pressure value, the PLC calculation and control device will automatically divide the instantaneous amount of corrosion inhibitor into two levels:

[0050] (1) When the calculated CO2 partial pressure value is between 0.021MPa (inclusive) and 0.21MPa (inclusive), the PLC calculation and control device will judge it as mild corrosion, and the amount of corrosion inhibitor added will be the recommended empirical value of 0.38L / 10 4 m 3 Combined with the recorded instantaneous flow value of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow of produced gas, and sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump through the communication cable based on the calculation result.

[0051] (2) When the calculated CO2 partial pressure value is greater than 0.21MPa, the PLC calculation and control device will judge it as moderate to severe corrosion, and the amount of corrosion inhibitor added will be the recommended empirical value of 0.66L / 10 4 m 3 Combined with the recorded instantaneous flow rate of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow rate of produced gas, and based on this calculation result, sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump through the communication cable.

[0052] During gas production operations, the PLC calculation and control device executes the above-mentioned data collection, process calculation, and logical judgment at any time, and issues control adjustment instructions, thereby realizing the automatic and precise filling function of the corrosion inhibitor.

[0053] The present invention is applicable to both automatic injection control of corrosion inhibitor at the rear end of the gas wellhead and automatic and precise injection control of corrosion inhibitor in a certain area of ​​the gas production system. Through real-time monitoring, data processing, logical judgment and automatic control, precise injection of corrosion inhibitor is achieved, which not only meets the demand for corrosion control, but also improves economy and rationality.

[0054] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An automatic control device for adding corrosion inhibitor, characterized in that: A corrosion inhibitor injection pipeline (3), a natural gas flow meter (6), a pressure transmitter (7), and a gas quality component analyzer (8) are sequentially connected to the gas production pipeline (2) along the gas outlet direction; the corrosion inhibitor injection pipeline (3) is provided with a corrosion inhibitor injection metering pump (10); and the corrosion inhibitor injection pipeline (3), the natural gas flow meter (6), the pressure transmitter (7), the gas quality component analyzer (8), and the corrosion inhibitor injection metering pump (10) are respectively connected to a PLC calculation and control device (9).

2. The automatic control device for adding corrosion inhibitor according to claim 1, characterized in that: The gas production pipeline (2) is provided with a corrosion inhibitor filling port (5), and the corrosion inhibitor injection pipeline (3) is connected to the corrosion inhibitor filling port (5).

3. The automatic control device for adding corrosion inhibitor according to claim 1, characterized in that: The corrosion inhibitor filling metering pump (10), the natural gas flow meter (6), the pressure transmitter (7), and the gas quality component analyzer (8) are respectively connected to the PLC calculation and control device (9) via communication cables (4).

4. The automatic control device for adding corrosion inhibitor according to claim 1, characterized in that: The corrosion inhibitor injection pipeline (3) is provided with a stop valve.

5. The automatic control device for adding corrosion inhibitor according to claim 1, characterized in that: Stop valves are respectively provided on the pipelines of the pressure transmitter (7) and the gas composition analyzer (8).

6. An automatic control method for adding corrosion inhibitor, characterized in that: Here are the steps: S1. The gas quality component analyzer performs online gas quality component analysis on the produced gas, the pressure transmitter collects the pressure of the produced gas, and the natural gas flow meter collects the instantaneous flow of the produced gas; S2, input the gas quality component analysis results, produced gas pressure and instantaneous flow rate into the PLC calculation and control device; S3. The PLC calculation and control device obtains the CO2 partial pressure by multiplying the CO2 volume molar percentage content and the produced gas pressure in the gas composition analysis results; and determines whether it is necessary to add corrosion inhibitor to the gas production system based on the CO2 partial pressure value.

7. The automatic control method for adding corrosion inhibitor according to claim 6, characterized in that: In step S3, if the CO2 partial pressure value is less than 0.021MPa, the gas production system does not need to be filled with corrosion inhibitor; if the CO2 partial pressure value is greater than or equal to 0.021MPa, the PLC calculation and control device sends a pump start command to the corrosion inhibitor filling metering pump to add corrosion inhibitor to the gas production system.

8. The automatic control method for adding corrosion inhibitor according to claim 6, characterized in that: In step S3, when the calculated CO2 partial pressure value is between 0.021MPa and 0.21MPa, the PLC calculation and control device determines it as mild corrosion, and the corrosion inhibitor is added at 0.3L / 10 4 m 3 -0.4L / 10 4 m 3 Combined with the recorded instantaneous flow value of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow of produced gas, and sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump based on the calculation result.

9. The automatic control method for adding corrosion inhibitor according to claim 6, characterized in that: In step S3, when the calculated CO2 partial pressure value is greater than 0.21MPa, the PLC calculation and control device determines it as moderate to severe corrosion, and the corrosion inhibitor is added at 0.6L / 10 4 m 3 -0.7L / 10 4 m 3 Combined with the recorded instantaneous flow rate of produced gas, the PLC calculation and control device automatically calculates the instantaneous amount of corrosion inhibitor added = 1.1 × 0.38 × instantaneous flow rate of produced gas, and sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump based on the calculation result.

10. The automatic control method for adding corrosion inhibitor according to any one of claims 6 to 9, characterized in that: The PLC calculation and control device sends an instantaneous corrosion inhibitor filling amount instruction to the corrosion inhibitor filling metering pump through the communication cable according to the calculation result.

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