High-sulfur natural gas metering and pressure guiding device, method and system

Abstract

The invention provides a high-sulfur natural gas metering and pressure guiding device, method and system, and the device is characterized in that pressure measurement equipment is communicated with a natural gas pipe wall through a first pipeline, the pressure measurement equipment is communicated with differential pressure measurement equipment through a second pipeline, and the differential pressure measurement equipment is connected with the natural gas pipe wall through a third pipeline; the differential pressure type flowmeter is installed in the natural gas pipeline, the second pipeline and the third pipeline are communicated with the pressure liquid accumulation tank through branch pipes respectively, and the liquid inlet ends of the differential pressure liquid accumulation tank, the pressure liquid accumulation tank and the differential pressure liquid accumulation tank are all provided with switch valves electrically connected with the pressure measuring device and the differential pressure measuring device. According to the invention, the state of the gas flow of the natural gas pipeline is firstly judged by the differential pressure type flowmeter, and then pressure and differential pressure detection is carried out on the natural gas in a steady state by the pressure measurement equipment and the differential pressure measurement equipment, so that the accuracy of the detection data is guaranteed, and the corresponding switch valves are opened in time; therefore, the maintenance workload of high-sulfur-content field equipment is reduced.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas measurement technology, and specifically relates to a high-sulfur natural gas metering and pressure guiding device, method and system. Background Technology

[0002] Differential pressure flow meters are currently the most widely used metering equipment in the field of high-sulfur natural gas trade and transfer. They rely on the differential pressure transmitter inside the flow meter to measure the pressure difference before and after the fluid, and convert the differential pressure signal into an electrical signal for processing. However, the conventional method of use is to install the differential pressure flow meter inside the high-sulfur natural gas pipeline and connect it to the high-sulfur natural gas in the pipeline. However, the high-sulfur natural gas being extracted itself contains impurities such as hydrogen sulfide, carbon dioxide, and water vapor. This causes the pressure chambers inside the differential pressure transmitter to be blocked by impurities, forming a leakage channel. This makes it impossible to effectively isolate the pressure between the high-pressure end and the low-pressure end, directly affecting the accuracy of the differential pressure flow meter's detection data.

[0003] Furthermore, for the production of high-sulfur natural gas, if cleaning is carried out regularly as required, normally once a week, it will directly increase the safety risks and workload at the production site. At the same time, if an internal leak occurs, it will be impossible to deal with it in time due to production needs and safety risks, which will bring great difficulties to the operation and management of high-sulfur natural gas.

[0004] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0005] To address the above problems, this invention proposes a high-sulfur natural gas metering and pressure guiding device, comprising: a pressure measuring device, a differential pressure measuring device, a pressure accumulator, a differential pressure accumulator, and a differential pressure flow meter;

[0006] The input end of the pressure measuring device is connected to the first port of the natural gas pipe wall through the first pipeline, the output end of the pressure measuring device is connected to the inlet end of the differential pressure measuring device through the second pipeline, and the output end of the differential pressure measuring device is connected to the second port located downstream of the first port of the natural gas pipe wall through the third pipeline.

[0007] The differential pressure flow meter is installed inside the natural gas pipeline and is positioned adjacent to the first and second ports;

[0008] The second and third pipelines are respectively connected to the pressure accumulator tank and the differential pressure accumulator tank via branch pipes;

[0009] The pressure measuring device, differential pressure measuring device, pressure accumulator, and differential pressure accumulator are all equipped with switch valves at their inlet ends. The switch valves of the pressure measuring device and pressure accumulator are electrically connected to the pressure measuring device, and the switch valves of the differential pressure measuring device and differential pressure accumulator are electrically connected to the differential pressure measuring device.

[0010] Furthermore, the pressure guiding device also includes: a temperature measuring device and a first heating device and a second heating device electrically connected to the temperature measuring device;

[0011] The temperature measuring device is connected to the third port located downstream of the second port on the natural gas pipeline wall;

[0012] The first heating device and the second heating device are installed on the first pipeline and the third pipeline, respectively.

[0013] Furthermore, the pressure guiding device also includes: a first control valve and a second control valve electrically connected to the differential pressure flow meter;

[0014] The first control valve is installed on the first pipeline located between the first heating device and the first port;

[0015] The second control valve is installed on the third pipeline located between the second heating device and the natural gas pipeline wall.

[0016] The present invention also proposes a pressure guiding method based on the above-mentioned high-sulfur natural gas metering and pressure guiding device, the pressure guiding method comprising the following steps:

[0017] Start the differential pressure flow meter to determine whether the gas flow in the natural gas pipeline is in a steady state;

[0018] When the gas flow is in a steady state, the pressure measuring device and differential pressure measuring device are activated to measure the gas flow in the natural gas pipeline. The first value obtained is the initial value. The pressure measuring device and differential pressure measuring device continue to measure the gas flow in the natural gas pipeline to obtain the actual measurement value.

[0019] The closing state of the switch valve is determined based on the actual measured value and the initial measured value.

[0020] Furthermore, the initial measurement values ​​include: initial pressure measurement value and initial differential pressure measurement value; the actual measurement values ​​include: actual pressure measurement value and actual differential pressure measurement value.

[0021] When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is equal to the actual differential pressure measurement value, open the switch valve of the pressure accumulator and close the switch valve of the pressure measuring device, and continue for the set time.

[0022] When the actual pressure measurement value is equal to the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator and the differential pressure accumulator, close the switch valves of the pressure measuring device and the differential pressure measuring device, and continue for the set time.

[0023] When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator and differential pressure accumulator, and close the switch valves of the pressure measuring device and differential pressure measuring device for a set time.

[0024] Furthermore, pressure-conducting methods also include:

[0025] Obtain the freezing point temperature of natural gas in the pipeline, and compare the temperature value of natural gas with the freezing point temperature by using temperature measuring equipment.

[0026] When the temperature is less than or equal to the freezing point temperature, start the first heating device and the second heating device.

[0027] When the temperature is higher than the freezing point, turn off the first heating device and the second heating device.

[0028] Furthermore, the criterion for determining whether the gas flow in the natural gas pipeline is in a steady state when starting a differential pressure flow meter is as follows:

[0029] The pressure difference of natural gas between the front and rear ends of the differential pressure flow meter is less than or equal to 0.5% of the natural gas pressure at the front end of the differential pressure flow meter, and the temperature difference of natural gas is less than or equal to 0.2 degrees.

[0030] The present invention also proposes a high-sulfur natural gas metering and pressure guiding system, including the above-mentioned high-sulfur natural gas metering and pressure guiding device, the pressure guiding system comprising:

[0031] The metering module is used to activate the differential pressure flow meter to determine whether the gas flow in the natural gas pipeline is in a steady state.

[0032] The pressure guiding module is used to start the pressure measuring device and differential pressure measuring device to measure the gas flow in the natural gas pipeline when the gas flow is in a steady state. The first value obtained by the measurement is the initial value. The pressure measuring device and differential pressure measuring device continuously measure the gas flow in the natural gas pipeline to obtain the actual measurement value.

[0033] Sewage discharge module: Used to determine the closed state of the switch valve based on the actual measured value and the initial measured value.

[0034] Furthermore, the initial measurement values ​​include: initial pressure measurement value and initial differential pressure measurement value; the actual measurement values ​​include: actual pressure measurement value and actual differential pressure measurement value.

[0035] The sewage discharge module is used to open the switch valve of the pressure accumulator and close the switch valve of the pressure measuring device when the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is equal to the actual differential pressure measurement value, for a set time.

[0036] When the actual pressure measurement value is equal to the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator and the differential pressure accumulator, close the switch valves of the pressure measuring device and the differential pressure measuring device, and continue for the set time.

[0037] When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator and differential pressure accumulator, and close the switch valves of the pressure measuring device and differential pressure measuring device for a set time.

[0038] Furthermore, it also includes: a heating module, used to obtain the freezing point temperature of natural gas in the natural gas pipeline, and to obtain the temperature value of natural gas through a temperature measuring device and compare it with the freezing point temperature;

[0039] When the temperature is less than or equal to the freezing point temperature, start the first heating device and the second heating device.

[0040] When the temperature is higher than the freezing point, turn off the first heating device and the second heating device.

[0041] Compared with the prior art, the embodiments of the present invention have at least the following advantages:

[0042] 1. This invention proposes a metering and pressure guiding device, method and system for high sulfur content natural gas. According to the actual process conditions on site, during the gas flow process in the natural gas pipeline, the state of the natural gas flow is judged by a differential pressure flow meter. Then, the natural gas is guided to the pressure measuring device and differential pressure measuring device through the first pipeline and the second pipeline to perform pressure and differential pressure detection on the natural gas in steady state, ensuring the accuracy of the detection data.

[0043] 2. Simultaneously, based on the fluctuations in pressure and differential pressure, the condition of impurities in the natural gas pipeline is determined. By electrically connecting the switching valves to the pressure and differential pressure measuring devices, the corresponding switching valves are promptly opened when changes in the detected values ​​are detected. This allows natural gas to flow into the pressure accumulator tank and / or differential pressure accumulator tank, separating and removing water and other impurities from the natural gas. This reduces the impact of impurities in the natural gas pipeline on the pressure and differential pressure measuring devices, preventing blockages. Furthermore, the pressure and differential pressure accumulator tanks can be used for temporary storage of impurities, reducing the maintenance workload of high-sulfur field equipment and extending the maintenance cycle of the unit.

[0044] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description and the drawings. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 A schematic diagram of a high-sulfur natural gas metering and pressure guiding device in an embodiment of the present invention is shown;

[0047] Figure 2 A schematic flowchart of the high-sulfur natural gas metering and pressure guiding method in an embodiment of the present invention is shown;

[0048] Figure 3 A block diagram of a high-sulfur natural gas metering and pressure guiding system according to an embodiment of the present invention is shown.

[0049] In the diagram, 1-pressure measuring device, 2-differential pressure measuring device, 3-pressure accumulator, 4-differential pressure accumulator, 5-temperature measuring device, 6-first heating device, 7-second heating device, 8-differential pressure flow meter, 9-first control valve, 10-second control valve, 11-first switching valve, 12-second switching valve, 13-third switching valve, 14-fourth switching valve. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] This invention provides a metering and pressure guiding device, method, and system for high-sulfur natural gas. It should be noted that the H2S volume fraction is 2%–10% or the mass content is 30 g / m³. 3 ~150g / m 3 Natural gas with high sulfur content is called high-sulfur natural gas; among which, Figure 1 A schematic diagram of a high-sulfur natural gas metering and pressure guiding device according to an embodiment of the present invention is shown. Figure 1The high-sulfur natural gas metering and pressure guiding device includes: pressure measuring device 1, differential pressure measuring device 2, pressure accumulator 3, differential pressure accumulator 4;

[0052] The input end of pressure measuring device 1 is connected to the first port of the natural gas pipe wall through the first pipeline;

[0053] The output end of pressure measuring device 1 is connected to the inlet end of differential pressure measuring device 2 via a second pipeline;

[0054] The output of differential pressure measuring device 2 is connected to a second port located downstream of the first port on the natural gas pipe wall via a third pipeline;

[0055] The differential pressure flow meter 8 is installed inside the natural gas pipeline and is arranged adjacent to the first port and the second port;

[0056] The second and third pipelines are respectively connected to the pressure accumulator tank 3 and the differential pressure accumulator tank 4 via branch pipes;

[0057] The pressure measuring device 1, differential pressure measuring device 2, pressure accumulator 3, and differential pressure accumulator 4 are all equipped with switch valves at their inlet ends. The switch valves of pressure measuring device 1 and pressure accumulator 3 are electrically connected to pressure measuring device 1, and the switch valves of differential pressure measuring device 2 and differential pressure accumulator 4 are electrically connected to differential pressure measuring device 2.

[0058] Based on the direction of natural gas flow within the natural gas pipeline, pressure measuring device 1, pressure accumulator 3, differential pressure measuring device 2, and differential pressure accumulator 4 are sequentially connected outside the natural gas pipeline. Considering the corrosiveness and toxicity of high-sulfur natural gas, directly measuring the pressure inside the pipeline poses certain risks. Therefore, this application guides the natural gas to pressure measuring device 1 and differential pressure measuring device 2 in a safe area through the first and third pipelines for reading and monitoring, thereby protecting the device.

[0059] Based on the actual on-site process conditions, during the gas flow process in the natural gas pipeline, differential pressure flow meters 8 are installed adjacent to the first and second ports in the natural gas pipeline. The differential pressure flow meters 8 determine the state of the gas flow in the natural gas pipeline. Then, the natural gas is diverted to the pressure measuring device 1 and differential pressure measuring device 2 through the first and second pipelines to detect the pressure and differential pressure of the natural gas in a steady state, ensuring the accuracy of the detection data.

[0060] Simultaneously, based on the fluctuations in pressure and differential pressure, the condition of impurities in the natural gas pipeline is determined. With the pressure measuring device 1 and pressure accumulator 3 electrically connected to the pressure measuring device 1, and the differential pressure measuring device 2 and differential pressure accumulator 4 electrically connected to the differential pressure measuring device 2, the pressure measuring device 1 and differential pressure measuring device 2 promptly open their corresponding valves when they detect changes in values. This allows natural gas to flow into pressure accumulator 3 and / or differential pressure accumulator 4, separating and removing water and other impurities from the natural gas until the data detected by pressure measuring device 1 and differential pressure measuring device 2 returns to normal. This reduces the impact of impurities in the natural gas pipeline on pressure measuring device 1 and differential pressure measuring device 2, preventing impurity blockage within them. Furthermore, pressure accumulator 3 and differential pressure accumulator 4 can be used for temporary storage of impurities, reducing the maintenance workload of high-sulfur field equipment and extending the maintenance cycle of the device.

[0061] Specifically, the pressure guiding device also includes: a temperature measuring device 5 and a first heating device 6 and a second heating device 7 electrically connected to the temperature measuring device 5;

[0062] Temperature measuring device 5 is connected to the third port located downstream of the second port on the natural gas pipeline wall;

[0063] The first heating device 6 and the second heating device 7 are installed on the first pipeline and the third pipeline, respectively.

[0064] By adding temperature measuring device 5, the temperature of natural gas in the natural gas pipeline can be detected. By linking with the first heating device 6 and the second heating device 7, the temperature of natural gas in the first and third pipelines can be controlled to prevent the natural gas in the first and third pipelines from solidifying due to low temperature. This would avoid affecting the accuracy of the detection data of pressure measuring device 1 and differential pressure measuring device 2, and also prevent the solidified natural gas from flowing into subsequent natural gas pipelines, thus maintaining the temperature stability in the first and third pipelines.

[0065] Specifically, the pressure guiding device also includes: a first control valve 9 and a second control valve 10 that are electrically connected to the differential pressure flow meter 8;

[0066] The first control valve 9 is installed on the first pipeline located between the first heating device 6 and the first port;

[0067] The second control valve 10 is installed on the third pipeline located between the second heating device 7 and the natural gas pipeline wall.

[0068] By establishing a connection between the first control valve 9, the second control valve 10 and the differential pressure flow meter 8, and based on the assumption that the gas flow in the natural gas pipeline is in a steady state after the differential pressure flow meter 8 is activated, the first control valve 9 and the second control valve 10 are adjusted to connect the first pipeline and the third pipeline with the natural gas pipeline. Since the natural gas in the first pipeline and the third pipeline is in an unsteady state, the natural gas contains more impurities and the proportion of impurities fluctuates greatly, which will directly affect the accuracy of the detection data of the pressure measuring device 1 and the differential pressure measuring device 2. The first control valve 9 and the second control valve 10 can directly prevent the unsteady natural gas from entering the first pipeline and the third pipeline, thereby further improving the protection of the pressure measuring device 1 and the differential pressure measuring device 2.

[0069] refer to Figure 2 The present invention also proposes a pressure guiding method based on the above-mentioned high-sulfur natural gas metering and pressure guiding device, the pressure guiding method comprising the following steps:

[0070] Start the differential pressure flow meter 8 to determine whether the gas flow in the natural gas pipeline is in a steady state;

[0071] When the gas flow is in a steady state, pressure measuring device 1 and differential pressure measuring device 2 are started to measure the gas flow in the natural gas pipeline. The first value obtained is the initial value of the measurement. Pressure measuring device 1 and differential pressure measuring device 2 continue to measure the gas flow in the natural gas pipeline to obtain the actual measurement value.

[0072] The closing state of the switch valve is determined based on the actual measured value and the initial measured value.

[0073] The pressure guiding method proposed in this application first determines the state of the gas flow in the natural gas pipeline to ensure that the composition of the natural gas to be detected by the pressure measuring device 1 and the differential pressure measuring device 2 is stable and the proportion of impurities is stable, so as to ensure the accuracy of the data when the pressure and differential pressure of the natural gas are subsequently detected. Finally, the actual measured value is compared with the initial measured value to determine whether the sewage discharge operation should be carried out.

[0074] The initial measurement values ​​include: initial pressure measurement values ​​and initial differential pressure measurement values; the actual measurement values ​​include: actual pressure measurement values ​​and actual differential pressure measurement values.

[0075] Based on pressure and differential pressure, the amount of impurities in the natural gas pipeline is determined, and then the opening and closing of the valves of pressure measuring device 1, differential pressure measuring device 2, pressure accumulator 3, and differential pressure accumulator 4 are controlled.

[0076] For ease of explanation, the pressure measuring device 1, differential pressure measuring device 2, pressure accumulator 3, and differential pressure accumulator 4 are respectively equipped with switch valves at their inlet ends, namely the first switch valve 11, the second switch valve 12, the third switch valve 13, and the fourth switch valve 14. In the initial stage of the device, the first switch valve 11 and the second switch valve 12 are kept in the open state, and the third switch valve 13 and the fourth switch valve 14 are kept in the closed state.

[0077] When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is equal to the actual differential pressure measurement value, open the third switch valve 13 of the pressure accumulator 3 and close the first switch valve 11 of the pressure measuring device 1, and continue for a set time.

[0078] The natural gas in the pipeline flows into the pressure accumulator 3 for gas and impurity separation. After a set time, the third switch valve 13 of the pressure accumulator 3 is closed, the first switch valve 11 of the pressure measuring device 1 is opened, and the pressure measuring device 1 and differential pressure measuring device 2 are restarted to continuously measure the gas flow in the natural gas pipeline and obtain the actual measurement value until the data detected by the pressure measuring device 1 returns to the same as the initial pressure measurement value.

[0079] When the actual pressure measurement value is equal to the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the third switch valve 13 of the pressure accumulator 3 and the fourth switch valve 14 of the differential pressure accumulator 4, and close the first switch valve 11 of the pressure measuring device 1 and the second switch valve 12 of the differential pressure measuring device 2, and continue for a set time.

[0080] The natural gas from the first and second pipelines flows to the pressure accumulator 3 for gas and impurity separation, while the natural gas in the differential pressure measuring device 2 flows to the differential pressure accumulator 4 for gas and impurity separation. After a set time, the third switch valve 13 and the fourth switch valve 14 are closed, and the first switch valve 11 and the second switch valve 12 are opened. The pressure measuring device 1 and the differential pressure measuring device 2 are restarted to continuously measure the gas flow in the natural gas pipeline and obtain the actual measurement value until the data detected by the differential pressure measuring device 2 returns to the same as the initial value of the differential pressure measurement.

[0081] When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the third switch valve 13 of the pressure accumulator 3 and the fourth switch valve 14 of the differential pressure accumulator 4, and close the first switch valve 11 of the pressure measuring device 1 and the second switch valve 12 of the differential pressure measuring device 2, and continue for a set time. The set time needs to be adjusted according to the specific situation on site. For example, the set time is 30-60 seconds.

[0082] Similarly, the natural gas from the first and second pipelines flows to the pressure accumulator 3 for gas and impurity separation, and the natural gas in the differential pressure measuring device 2 flows to the differential pressure accumulator 4 for gas and impurity separation. After waiting for a set time, the third switch valve 13 and the fourth switch valve 14 are closed, and the first switch valve 11 and the second switch valve 12 are opened. The pressure measuring device 1 and the differential pressure measuring device 2 are restarted to continuously measure the gas flow in the natural gas pipeline and obtain the actual measurement value until the actual measurement value returns to the same as the initial measurement value.

[0083] The method of this application takes the first measured value as the initial value. Based on the initial value as a reference value, the actual measured value is obtained and compared with the initial value in real time. With the pressure measuring device 1 and the pressure accumulator 3 electrically connected to the pressure measuring device 1, and the differential pressure measuring device 2 and the differential pressure accumulator 4 electrically connected to the differential pressure measuring device 2, the corresponding valve can be directly driven to open or close as soon as the comparison result between the actual measured value and the initial measured value is obtained. This greatly ensures the timeliness of sewage discharge operations and the accuracy of the detection data.

[0084] Correspondingly, pressure guiding methods also include:

[0085] The freezing point temperature of natural gas in the pipeline is obtained, and the temperature value of natural gas is obtained by temperature measuring device 5 and compared with the freezing point temperature.

[0086] When the temperature is less than or equal to the freezing point temperature, start the first heating device 6 and the second heating device 7.

[0087] When the temperature is higher than the freezing point, shut down the first heating device 6 and the second heating device 7.

[0088] By controlling the minimum temperature limit of natural gas, the temperature of natural gas in the first and third pipelines is always above the freezing point, preventing water vapor in the natural gas in the pipeline from freezing and reducing the accuracy of all data. At the same time, the first heating device 6 and the second heating device 7 can also ensure that the medium in the first and third pipelines remains in a gaseous state, reducing liquid precipitation.

[0089] Specifically, in the process of starting the differential pressure flow meter 8 to determine whether the gas flow in the natural gas pipeline is in a steady state, the corresponding judgment condition is as follows:

[0090] The pressure difference between the natural gas before and after the differential pressure flow meter 8 is less than or equal to 0.5% of the natural gas pressure before the differential pressure flow meter 8, and the temperature difference of the natural gas is less than or equal to 0.2 degrees, so as to ensure the variation of natural gas composition.

[0091] To further illustrate the metering and pressure guiding method for high-sulfur natural gas proposed in this invention, the following supplementary explanations are provided;

[0092] High-sulfur natural gas should be selected with a hydrogen sulfide (H2S) volume fraction of 2%–10% or a mass content of 30 g / m³. 3 ~150g / m 3 Natural gas;

[0093] The temperature value T0 in the natural gas pipeline is obtained by temperature measuring device 5, and the freezing point temperature T1 of the natural gas is obtained to determine the status of the first heating device 6 and the second heating device 7.

[0094] That is, when the temperature value T0 is less than or equal to the freezing point temperature T1, the first heating device 6 and the second heating device 7 are started;

[0095] When the temperature T0 is greater than the freezing point temperature T1, turn off the first heating device 6 and the second heating device 7.

[0096] When the natural gas pressure fluctuation detected by the differential pressure flow meter 8 in the natural gas pipeline is less than or equal to 0.5% of the natural gas pressure at the front end of the differential pressure flow meter 8 and the natural gas temperature fluctuation is less than or equal to 0.2 degrees, the first control valve 9 and the second control valve 10 are opened.

[0097] The initial pressure measurement value P1 and the initial differential pressure measurement value ΔP1 are obtained through pressure measuring device 1 and differential pressure measuring device 2.

[0098] During the normal flow of natural gas in the natural gas pipeline, the natural gas is detected in real time by pressure measuring device 1 and differential pressure measuring device 2, and the actual pressure measurement value P2 and the actual differential pressure measurement value ΔP2 are obtained.

[0099] When the actual pressure measurement value P2 is greater than or less than the initial pressure measurement value P1, and the initial differential pressure measurement value ΔP1 is equal to the actual differential pressure measurement value ΔP2, the third switch valve 13 of the pressure accumulator 3 is opened and the first switch valve 11 of the pressure measuring device 1 is closed, and this continues for a set time.

[0100] When the actual pressure measurement value P2 is equal to the initial pressure measurement value P1, and the initial differential pressure measurement value ΔP1 is greater than or less than the actual differential pressure measurement value ΔP2, the third switch valve 13 of the pressure accumulator 3 and the fourth switch valve 14 of the differential pressure accumulator 4 are opened, and the first switch valve 11 of the pressure measuring device 1 and the second switch valve 12 of the differential pressure measuring device 2 are closed, for a set time.

[0101] When the actual pressure measurement value P2 is greater than or less than the initial pressure measurement value P1, and the initial differential pressure measurement value ΔP1 is greater than or less than the actual differential pressure measurement value ΔP2, the third switch valve 13 of the pressure accumulator 3 and the fourth switch valve 14 of the differential pressure accumulator 4 are opened, and the first switch valve 11 of the pressure measuring device 1 and the second switch valve 12 of the differential pressure measuring device 2 are closed, for a set time.

[0102] Based on the above principles, refer to Figure 3 The present invention also proposes a high-sulfur natural gas metering and pressure guiding system, including a high-sulfur natural gas metering and pressure guiding device as described above, the pressure guiding system comprising:

[0103] The metering module is used to activate the differential pressure flow meter 8 to determine whether the gas flow in the natural gas pipeline is in a steady state.

[0104] The pressure guiding module is used to start the pressure measuring device 1 and the differential pressure measuring device 2 to measure the airflow in the natural gas pipeline when the airflow is in a steady state. The first value obtained by the measurement is the initial value. The pressure measuring device 1 and the differential pressure measuring device 2 continue to measure the airflow in the natural gas pipeline to obtain the actual measurement value.

[0105] Sewage discharge module: Used to determine the closed state of the switch valve based on the actual measured value and the initial measured value.

[0106] Initial measurement values ​​include: initial pressure measurement value and initial differential pressure measurement value; actual measurement values ​​include: actual pressure measurement value and actual differential pressure measurement value.

[0107] The sewage discharge module is used to open the third switch valve 13 of the pressure accumulator 3 and close the first switch valve 11 of the pressure measuring device 1 when the actual pressure measurement value is greater than or less than the initial pressure measurement value and the actual differential pressure measurement value is equal to the actual differential pressure measurement value, and to continue for a set time.

[0108] When the actual pressure measurement value is equal to the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the third switch valve 13 of the pressure accumulator 3 and the fourth switch valve 14 of the differential pressure accumulator 4, and close the first switch valve 11 of the pressure measuring device 1 and the second switch valve 12 of the differential pressure measuring device 2, and continue for a set time.

[0109] When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, the third switch valve 13 of the pressure accumulator 3 and the fourth switch valve 14 of the differential pressure accumulator 4 are opened, and the first switch valve 11 of the pressure measuring device 1 and the second switch valve 12 of the differential pressure measuring device 2 are closed, for a set time.

[0110] The pressure guiding system also includes a heating module, which is used to obtain the freezing point temperature of the natural gas in the natural gas pipeline, and to obtain the temperature value of the natural gas through the temperature measuring device 5 and compare it with the freezing point temperature;

[0111] When the temperature is less than or equal to the freezing point temperature, start the first heating device 6 and the second heating device 7.

[0112] When the temperature is higher than the freezing point, shut down the first heating device 6 and the second heating device 7.

[0113] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of multiple components or the interaction between multiple components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0114] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-sulfur natural gas metering and pressure guiding device, used for metering natural gas on a natural gas pipeline, characterized in that, include: Pressure measuring device (1), differential pressure measuring device (2), pressure accumulator (3), differential pressure accumulator (4), differential pressure flow meter (8); The input end of the pressure measuring device (1) is connected to the first port of the natural gas pipe wall through the first pipeline, the output end of the pressure measuring device (1) is connected to the inlet end of the differential pressure measuring device (2) through the second pipeline, and the output end of the differential pressure measuring device (2) is connected to the second port located downstream of the first port of the natural gas pipe wall through the third pipeline. The differential pressure flow meter (8) is installed in the natural gas pipeline and is arranged adjacent to the first port and the second port. The second pipeline and the third pipeline are respectively connected to the pressure accumulator (3) and the differential pressure accumulator (4) through branch pipes. The pressure measuring device (1), differential pressure measuring device (2), pressure accumulator (3), and differential pressure accumulator (4) are all equipped with switching valves at their inlet ends. The switching valves of the pressure measuring device (1) and pressure accumulator (3) are electrically connected to the pressure measuring device (1), and the switching valves of the differential pressure measuring device (2) and differential pressure accumulator (4) are electrically connected to the differential pressure measuring device (2).

2. The high-sulfur natural gas metering and pressure guiding device according to claim 1, characterized in that, The pressure guiding device further includes: a temperature measuring device (5) and a first heating device (6) and a second heating device (7) electrically connected to the temperature measuring device (5); The temperature measuring device (5) is connected to a third port located downstream of the second port of the natural gas pipeline wall; The first heating device (6) and the second heating device (7) are respectively installed on the first pipeline and the third pipeline.

3. The high-sulfur natural gas metering and pressure guiding device according to claim 2, characterized in that, The pressure guiding device further includes: a first control valve (9) and a second control valve (10) electrically connected to the differential pressure flow meter (8); The first control valve (9) is installed on the first pipeline located between the first heating device (6) and the first port; The second control valve (10) is installed on the third pipeline located between the second heating device (7) and the natural gas pipeline wall.

4. A method for metering and guiding pressure of high-sulfur natural gas, characterized in that, The high-sulfur natural gas metering and pressure guiding device according to any one of claims 1-3, wherein the pressure guiding method comprises the following steps: Start the differential pressure flow meter (8) to determine whether the gas flow in the natural gas pipeline is in a steady state; When the gas flow is in a steady state, the pressure measuring device (1) and the differential pressure measuring device (2) are started to measure the gas flow in the natural gas pipeline. The first value obtained by the measurement is the initial value of the measurement. The pressure measuring device (1) and the differential pressure measuring device (2) continue to measure the gas flow in the natural gas pipeline to obtain the actual measurement value. The closing state of the switch valve is determined based on the actual measured value and the initial measured value.

5. The method for metering and guiding pressure of high-sulfur natural gas according to claim 4, characterized in that, The initial measurement values ​​include: initial pressure measurement value and initial differential pressure measurement value; the actual measurement values ​​include: actual pressure measurement value and actual differential pressure measurement value. When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is equal to the actual differential pressure measurement value, open the switch valve of the pressure accumulator (3) and close the switch valve of the pressure measuring device (1) for a set time. When the actual pressure measurement value is equal to the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator (3) and the differential pressure accumulator (4), close the switch valves of the pressure measuring device (1) and the differential pressure measuring device (2), and continue for a set time. When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator (3) and the differential pressure accumulator (4), close the switch valves of the pressure measuring device (1) and the differential pressure measuring device (2), and continue for a set time.

6. The method for metering and guiding pressure of high-sulfur natural gas according to claim 4, characterized in that, The pressure guiding method further includes: Obtain the freezing point temperature of natural gas in the natural gas pipeline, and obtain the temperature value of natural gas through temperature measuring device (5) and compare it with the freezing point temperature; When the temperature value is less than or equal to the freezing point temperature, start the first heating device (6) and the second heating device (7); When the temperature value is higher than the freezing point temperature, turn off the first heating device (6) and the second heating device (7).

7. The method for metering and guiding pressure of high-sulfur natural gas according to claim 4, characterized in that, The condition for the differential pressure flow meter (8) to determine whether the gas flow in the natural gas pipeline is in a steady state is as follows: The pressure difference between the front and rear ends of the differential pressure flow meter (8) is less than or equal to 0.5% of the pressure of the natural gas at the front end of the differential pressure flow meter (8), and the temperature difference of the natural gas is less than or equal to 0.2 degrees.

8. A metering and pressure guiding system for high-sulfur natural gas, characterized in that, A high-sulfur natural gas metering and pressure guiding device according to any one of claims 1-3, wherein the pressure guiding system comprises: The metering module is used to start the differential pressure flow meter (8) to determine whether the gas flow in the natural gas pipeline is in a steady state; Pressure guiding module; used to start the pressure measuring device (1) and differential pressure measuring device (2) to measure the airflow in the natural gas pipeline when the airflow is in a steady state. The first value obtained by the measurement is the initial value of the measurement. The pressure measuring device (1) and differential pressure measuring device (2) continuously measure the airflow in the natural gas pipeline to obtain the actual measurement value. Sewage discharge module: Used to determine the closed state of the switch valve based on the actual measured value and the initial measured value.

9. The high-sulfur natural gas metering and pressure guiding system according to claim 8, characterized in that, The initial measurement values ​​include: initial pressure measurement value and initial differential pressure measurement value; the actual measurement values ​​include: actual pressure measurement value and actual differential pressure measurement value. The sewage discharge module is used to open the switch valve of the pressure accumulator (3) and close the switch valve of the pressure measuring device (1) when the actual pressure measurement value is greater than or less than the initial pressure measurement value and the actual differential pressure measurement value is equal to the actual differential pressure measurement value, and to continue for a set time. When the actual pressure measurement value is equal to the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator (3) and the differential pressure accumulator (4), close the switch valves of the pressure measuring device (1) and the differential pressure measuring device (2), and continue for a set time. When the actual pressure measurement value is greater than or less than the initial pressure measurement value, and the actual differential pressure measurement value is greater than or less than the actual differential pressure measurement value, open the switch valves of the pressure accumulator (3) and the differential pressure accumulator (4), close the switch valves of the pressure measuring device (1) and the differential pressure measuring device (2), and continue for a set time.

10. The high-sulfur natural gas metering and pressure guiding system according to claim 8, characterized in that, Also includes: The heating module is used to obtain the freezing point temperature of natural gas in the natural gas pipeline. The temperature value of natural gas is obtained by the temperature measuring device (5) and compared with the freezing point temperature. When the temperature value is less than or equal to the freezing point temperature, start the first heating device (6) and the second heating device (7); When the temperature value is higher than the freezing point temperature, turn off the first heating device (6) and the second heating device (7).

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