Dynamic pressure boosting method of gas field gathering and transportation processing system and gas field gathering and transportation processing system

Abstract

The present application relates to the technical field of gas field development, and provides a dynamic pressurization method of a gas field gathering and transportation treatment system and the gas field gathering and transportation treatment system.The method comprises the following steps: under the condition that the total treatment gas volume of the gathering and transportation treatment system gradually decreases, dynamically reducing the operation pressure of the treatment system, and ensuring that the operation pressure of the treatment system after being reduced is higher than and close to the minimum operation pressure of the treatment system; in the process of dynamically reducing the operation pressure of the treatment system, adjusting the pressurization scheme of the gathering and transportation system to reduce the total pressurization production cost of the gathering and transportation system.The dynamic pressurization method of "combining pressurized gathering and transportation with pressure reduction treatment" is adopted, the operation pressure of the treatment system is dynamically reduced, and the pressurization scheme of the gathering and transportation system is dynamically adjusted, so that the pressurized gathering and transportation production cost can be reduced to the maximum extent.

Description

Technical Field

[0001] This invention relates to the field of gas field development technology, and more specifically to a dynamic pressurization method for a gas field gathering and processing system, as well as a gas field gathering and processing system. Background Technology

[0002] Gas field development primarily relies on formation energy for gas well production. Natural gas flows from the well bottom to the surface using its own energy, and is then transported to gathering / processing stations via existing gathering and transmission pipelines. After dehydration, desulfurization / decarbonization, and meeting commercial gas quality standards, it is delivered to downstream users. In the later stages of gas field development, as the well production time increases, formation energy gradually diminishes, and the well pressure and production gradually decrease. When the wellhead pressure reaches or approaches the transmission pressure of the gathering and transmission pipeline, the wellhead gas cannot normally enter the gathering and transmission pipeline to flow to the processing terminal. Moreover, as the gas well is produced, the liquid production also gradually increases. However, as the well pressure and production decrease, the gas velocity in the wellbore decreases, and the gas energy is insufficient to carry the liquid from the well bottom to the surface. Therefore, the liquid accumulates at the bottom of the well, leading to sand production in the tubing, clay expansion, decreased production, and even well shutdown.

[0003] When gas well oil pressure falls below the gathering and transportation system pressure, preventing normal production (intermittent production / well shut-in), a pressurized gathering and transportation process is required. This process increases the pressure of low-pressure natural gas to above the operating pressure of the downstream gathering and processing system, effectively solving the problem of insufficient wellhead pressure in the later stages of gas field development, preventing normal production. However, this also leads to a problem: as the low-pressure of gas wells further decreases and the number of low-pressure wells gradually increases, the energy consumption and operating costs of gas field production increase significantly, hindering the development efficiency of the gas field. Summary of the Invention

[0004] The purpose of this invention is to provide a dynamic pressurization method for a gas field gathering and transportation system, so as to reduce the production cost of pressurized gathering and transportation.

[0005] To achieve the above objectives, the present invention provides a dynamic pressurization method for a gas field gathering and processing system, the gathering and processing system comprising a gathering and processing system and a processing system, the method comprising:

[0006] Under the condition that the total gas volume processed by the gathering and transmission system gradually decreases, the operating pressure of the processing system is dynamically reduced, and the reduced operating pressure of the processing system is ensured to be higher than and close to the minimum operating pressure of the processing system.

[0007] In the process of dynamically reducing the operating pressure of the processing system, the pressurization scheme of the gathering and transportation system is adjusted to reduce the total pressurization production cost of the gathering and transportation system.

[0008] In this embodiment of the invention, the method further includes: predicting the total gas volume processed by the gathering and processing system in each time period of gas field production; and determining the minimum operating pressure of the processing system in each time period based on the total gas volume processed by the gathering and processing system in each time period.

[0009] In this embodiment of the invention, the step of dynamically reducing the operating pressure of the processing system under the condition that the total processing volume of the gathering and transmission processing system gradually decreases includes: reducing the operating pressure of the processing system in each time period, so that the operating pressure in that time period is higher than and close to the minimum operating pressure of that time period, and keeping the operating pressure unchanged until the end of that time period.

[0010] In this embodiment of the invention, adjusting the pressurization scheme of the gathering and transportation system during the process of dynamically reducing the operating pressure of the processing system includes: adjusting the pressurization method and pressurization pressure of the pressurized gas wells of the gathering and transportation system in each time period after reducing the operating pressure of the processing system.

[0011] In this embodiment of the invention, after reducing the operating pressure of the processing system, the pressurization method and pressurization pressure of the pressurized gas wells in the gathering and transportation system are adjusted, including: after reducing the operating pressure of the processing system, reducing the centralized pressurization outlet pressure of the gathering and transportation system to be higher than and close to the operating pressure of the processing system, and correspondingly reducing the centralized pressurization inlet pressure; when the pressure of the pressurized gas well is greater than the operating pressure of the processing system after the pressure reduction, suspending the pressurization of the pressurized gas well; when the pressure of the pressurized gas well pressurized using the single-well pressurization method is greater than the adjusted operating pressure of the centralized pressurization inlet, switching the single-well pressurization method to the centralized pressurization method.

[0012] In this embodiment of the invention, after reducing the operating pressure of the processing system, the pressurization method and pressurization pressure of the pressurized gas wells in the gathering and transportation system are adjusted. The adjustment further includes: when the pressure of the pressurized gas wells pressurized by the single-well pressurization method is still lower than the operating pressure of the adjusted centralized pressurization inlet, the single-well pressurization outlet pressure is reduced to be higher than and close to the operating pressure of the processing system.

[0013] Another aspect of the present invention provides a gas field gathering and processing system, including a gathering and processing system and further comprising:

[0014] The pressure regulation system is used to dynamically reduce the operating pressure of the processing system as the total gas volume of the gathering and transmission system gradually decreases, and to ensure that the reduced operating pressure of the processing system is higher than and close to the minimum operating pressure of the processing system. In addition, the system adjusts the pressurization scheme of the gathering and transmission system during the process of dynamically reducing the operating pressure of the processing system, so as to reduce the total pressurization production cost of the gathering and transmission system.

[0015] In this embodiment of the invention, the pressure regulation system is also used to predict the total gas volume processed by the gathering and transportation system in each time period of gas field production, and to determine the minimum operating pressure of the processing system in each time period based on the total gas volume processed by the gathering and transportation system in each time period.

[0016] In this embodiment of the invention, after reducing the operating pressure of the processing system, the pressure regulating system adjusts the pressurization method and pressurization pressure of the pressurized gas well in the gathering and transportation system.

[0017] In this embodiment of the invention, the gathering and transportation system includes a single-well field booster compressor connected to the wellhead of a gas well and a centralized booster compressor connected to multiple wellheads. The outlet of the centralized booster compressor and the outlet of the single-well field booster compressor are connected to the processing system through a production gas collection pipeline.

[0018] For gas wells with single-well field pressurization, the pressure regulation system reduces the pressurization pressure on the gas well by lowering the outlet pressure of the single-well field pressurization compressor connected to the wellhead of the single gas well.

[0019] For gas wells with centralized pressurization, the pressure regulation system reduces the centralized pressurization pressure by lowering the outlet pressure of the centralized pressurization compressor connected to multiple gas wellheads.

[0020] This invention employs a dynamic pressurization method that combines pressurized collection and transportation with depressurization processing. Based on the traditional, relatively fixed static pressurized collection and transportation mode, it considers the collection and transportation system and the processing system as the main body for pressurization optimization. It dynamically reduces the operating pressure of the processing system while dynamically adjusting the pressurization pressure of the collection and transportation system to ensure that the pressurized pressure of the collection and transportation system is higher than and close to the minimum operating pressure of the processing system, thereby minimizing the production cost of pressurized collection and transportation.

[0021] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0023] Figure 1 A flowchart of the dynamic pressurization method for a gas field gathering and transportation system provided in an embodiment of the present invention;

[0024] Figure 2 This is a structural block diagram of a gas field gathering and processing system provided in a typical embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures

[0026] 1-Gas well, 2-Gas well site, 3-Single well site booster compressor, 4-Single well gas production pipeline

[0027] 5-Centralized booster gas pipeline, 6-Centralized booster compressor, 7-Production gas pipeline,

[0028] 8-Processing system, 9-Gathering and processing station. Detailed Implementation

[0029] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0030] A gas field gathering, transportation, and processing system comprises a front-end gathering and transportation system and a back-end processing system. The gathering and transportation system refers to the system where natural gas, after being extracted from gas wells, undergoes throttling and depressurization, liquid separation and removal, and metering before being transported via the gathering trunk line to a natural gas processing plant or the first station of a long-distance pipeline. The gathering and transportation system process includes key components such as the well site, gas production pipeline, gathering station, gathering pipeline, and the transmission pipeline to the processing station. The scheme of the gathering and transportation system is determined by comprehensively considering factors such as natural gas properties, gas well production, gas well pressure and temperature, gas field structure, drive type, well network layout, and natural conditions. The processing system treats the natural gas transported by the gathering and transportation system, performing processes such as desulfurization, dehydration, and carbon dioxide separation to bring it up to usable standards.

[0031] Figure 1 This is a flowchart illustrating the dynamic pressurization method for a gas field gathering and processing system provided in an embodiment of the present invention. Figure 1 As shown in the figure, this embodiment of the invention provides a dynamic pressurization method for a gas field gathering and processing system, comprising the following steps:

[0032] Step 102: Under the condition that the total gas volume of the gathering and transmission processing system gradually decreases, dynamically reduce the operating pressure of the processing system, and ensure that the reduced operating pressure of the processing system is higher than and close to the minimum operating pressure of the processing system.

[0033] Step 104: In the process of dynamically reducing the operating pressure of the processing system, the pressurization scheme of the gathering and transportation system is adjusted to reduce the total pressurization production cost of the gathering and transportation system.

[0034] Boosting production is a common method used in the mid-to-late stages of gas field development. In the traditional boosting mode, the operating pressure of the downstream processing system is constant. When the gas well pressure decreases below the operating pressure of the processing system, boosting production needs to be started. As the number of boosting wells increases, the boosting cost rises significantly. As the gas well pressure and production further decrease, the boosting cost per unit of gas volume further increases, resulting in high boosting and gathering costs, which to varying degrees restrict the development efficiency of the gas field.

[0035] It should be noted that the operating pressure of the processing system being higher than and close to the minimum operating pressure of the processing system means that the operating pressure of the processing system is slightly higher than or approximately equal to (infinitely close to) the minimum operating pressure. For example, if the minimum operating pressure of the processing system is 4.50 MPa, then the reduced operating pressure of the processing system should be between 4.51 MPa and 4.60 MPa, between 4.501 MPa and 4.550 MPa, or between 4.50 MPa and 4.90 MPa. The difference between the operating pressure of the processing system and the minimum operating pressure can be preset according to the actual situation. The smaller the preset difference, the lower the cost. The preset difference must be a positive number, not a negative number, and the minimum is zero.

[0036] This invention employs a dynamic pressurization method that combines pressurized collection and transportation with depressurization processing. Based on the traditional, relatively fixed static pressurized collection and transportation mode, it considers the collection and transportation system and the processing system as the main body for pressurization optimization. It dynamically reduces the operating pressure of the processing system while dynamically adjusting the pressurization pressure of the collection and transportation system to ensure that the pressurized pressure of the collection and transportation system is higher than and close to (slightly higher than) the operating pressure of the processing system, thereby minimizing the production cost of pressurized collection and transportation.

[0037] In the later stages of gas field development, as pressure decreases, so does production; that is, the pressure and production of gas wells gradually decrease throughout the entire production cycle of the gas field. The gas field's production cycle is divided into multiple smaller time periods. Within a small time period, the pressure and production of gas wells change only slightly, while in subsequent consecutive time periods, the pressure and production of gas wells gradually decrease. Before implementing dynamic pressurization, based on the current pressure and production of all gas wells in the gas field, and the future production and pressure of new and old gas wells, the production parameters of the gathering and processing system for each time period can be predicted. These parameters include the total pressurization volume of low-pressure gas wells in different pressure ranges, the total gas volume processed by the system, and the pressure distribution of gas wells. Based on the gas field's production decline and the gas field development professionals' predictions of gas well pressure and production, the minimum allowable operating pressure of the processing system, while still meeting the gas volume processing requirements, can be calculated. For example, based on the process principles of the treatment system (such as acid gas removal by alkanolamine method and dehydration by triethylene glycol), calculations are performed by combining theoretical calculations and simulation software to determine the minimum allowable operating pressure of the treatment system under different treatment volume conditions as the total treated gas volume decreases.

[0038] In one embodiment, before dynamic pressurization adjustments, the total gas volume processed by the gathering and processing system in each time period of gas field production is predicted. Based on the total gas volume processed by the gathering and processing system in each time period, the minimum operating pressure of the processing system in each time period is determined. The operating pressure of the processing system is reduced in each time period, making the operating pressure in that time period higher than and close to (slightly higher than) the minimum operating pressure of that time period, and then kept constant until the end of that time period. For example, in the current time period, the operating pressure of the processing system is reduced to an amount infinitely higher than and close to the minimum operating pressure of the current time period, and then kept constant until the end of the current time period; in the next time period, the operating pressure of the processing system is reduced to an amount infinitely higher than and close to the minimum operating pressure of the next time period, and then kept constant until the end of the next time period; in this way, the operating pressure of the processing system is gradually reduced in each time period. Reducing the operating pressure of the processing system can correspondingly reduce the production energy consumption of the processing system.

[0039] In each time period, after reducing the operating pressure of the processing system, the pressurization method and pressure of the booster wells in the gathering and transportation system are adjusted to ensure that the pressurized pressure of the gathering and transportation system is higher than and close to (slightly higher than) the operating pressure of the processing system, thereby minimizing the production cost of pressurized gathering and transportation. Specifically, after reducing the operating pressure of the processing system, the centralized booster outlet pressure of the gathering and transportation system is reduced to be higher than and close to the operating pressure of the processing system, and the centralized booster inlet pressure is reduced accordingly; when the pressure of a boosted well is higher than the operating pressure of the processing system after pressure reduction, pressurization of that boosted well is suspended; when the pressure of a boosted well using the single-well boosting method is higher than the adjusted operating pressure of the centralized booster inlet, the single-well boosting method is switched to the centralized boosting method; when the pressure of a boosted well using the single-well boosting method is still lower than the adjusted operating pressure of the centralized booster inlet, the single-well booster outlet pressure is reduced to be higher than and close to the operating pressure of the processing system. It should be noted that the difference between the pressure after the collection and transportation system is pressurized and the operating pressure of the processing system can be preset according to the actual situation. The smaller the preset difference, the lower the cost. The preset difference must be a positive number and cannot be a negative number.

[0040] In one embodiment, optimizing the pressurization scheme of the gathering and transportation system includes: reducing the pressurization pressure of the pressurized gas wells when the pressure of the pressurized gas wells exceeds the operating pressure of the processing system, or suspending pressurization of the pressurized gas wells, delaying the pressurization timing, and reducing the number of pressurized wells to reduce pressurization costs. For gas wells with centralized pressurization, the outlet pressure of the centralized pressurization compressor is reduced; for gas wells with single-wellfield pressurization, the outlet pressure of the single-wellfield pressurization compressor is reduced. The compressor outlet pressure is usually the operating pressure of the downstream processing system. Reducing the compressor outlet pressure can reduce the compressor pressure ratio, which can effectively reduce the compressor power and thus reduce the compressor's production energy consumption.

[0041] In this embodiment of the invention, the minimum operating pressure of the processing system is determined based on the requirement that the reduced operating pressure must ensure that the processing capacity of the processing device can meet the gas volume demand when operating at that pressure. During each pressure reduction operation phase of the processing system, i.e., after each adjustment of the processing system's operating pressure, the pressurization scheme of the gathering and transportation system needs to be adjusted accordingly. This adjustment includes determining whether pressurized wells need further pressurization. If further pressurization is not needed, it is cancelled. If further pressurization is needed, the pressurization method (single-well pressurization or centralized pressurization) and pressurization pressure are optimized (e.g., selecting pressurization equipment, replacing high-power compressors with low-power compressors). The goal of adjusting the pressurization scheme is to minimize the total pressurization production cost.

[0042] The dynamic increase method combining pressurized collection and depressurization provided in this embodiment of the invention dynamically and gradually reduces the operating pressure of the processing system as the output decreases, and optimizes the pressurized collection part accordingly. Compared with the existing pressurized collection method, it is more flexible and has greater potential for cost reduction.

[0043] The following provides an exemplary example to describe the application and effects of the technical solution of the present invention.

[0044] A gas gathering and processing station at a certain gas production plant was completed and put into operation in 2009, with a natural gas purification capacity of 300×10⁻⁶. 4 m 3 / d, construct 2 natural gas purification units (each unit is 150×10) 4 m 3 / d), using MDEA decarbonization technology, the decarbonization depth reaches the purification of natural gas with CO2 content ≤3%. After decarbonization, the natural gas is dehydrated using triethylene glycol technology, and the water dew point of the exported natural gas is ≤-5℃, meeting the quality requirements of the exported natural gas.

[0045] At the beginning of 2021, the gas field had 36 gas wells with a feedstock gas production of approximately 250 × 10⁻⁶. 4 m 3 / d, the extracted water volume is approximately 900m³ 3 / d. Due to the long development period and rapid depletion of formation energy, the oil pressure in gas wells has decreased. Many gas wells are unable to enter the surface gathering and transportation system due to low wellhead oil pressure, resulting in a significant increase in well production. The gas well pressure is no longer suitable for the existing gathering and transportation system, necessitating pressurization for production. Pressurization production began in 2019, with 25 wells undergoing single-well pressurization, 6 wells undergoing centralized pressurization, and only 5 wells producing flowing gas. The cost of pressurization has been increasing year by year, hindering the economic benefits of the gas field.

[0046] In 2021, to further reduce the production cost of boosted gathering and transportation, a dynamic combined boosting mode of "boosting and gathering combined with depressurization treatment" was adopted. Firstly, based on development data such as output and pressure, a theoretical calculation model of acid gas load and Aspen HYSYS simulation software were used to calculate the current total gas processing capacity (250 × 10⁻⁶). 4 m 3 / d) To meet the processing requirements, the minimum allowable operating pressure of the processing system is 5 MPa. Corresponding optimizations were made to the front-end booster and distribution system. A dynamic boosting scheme was implemented on-site in August 2021, achieving good results.

[0047] (1) Add one compressor to the centralized booster unit, and operate 3 compressors. Switch YP21, YP20, YP23 and YP25 into the overall booster. The compressor inlet pressure drops from 3.2MPa to 2.7-2.8MPa, the compressor discharge pressure drops to 5.7MPa, and the daily natural gas processing capacity increases from 880,000 cubic meters to 1,306,000 cubic meters.

[0048] (2) After the treatment device is reduced to 5MPa, the daily total power consumption of the single-well booster field is reduced by about 17,100 kWh by reducing the number of booster fields, adjusting the compressor selection, and reducing the compression exhaust pressure. The daily electricity cost is reduced by about 9,405 yuan, and the annual electricity cost is reduced by about 3,291,750 yuan.

[0049] (3) When the treatment device is running at 5MPa, the total daily power consumption of the lean liquid pump of the decarbonization device will be reduced by about 12,000 kWh, saving about RMB 0.055 million in electricity costs per day and RMB 192,500 per year.

[0050] In early 2022, the total gas processing volume of the gas field further decreased to 240 × 10⁻⁶. 4 m 3 / d, after process calculation of the processing system, the operating pressure of the processing system was further reduced to 4.5MPa, which can meet the processing requirements, and the front-end booster collection and transportation system was further optimized and adjusted accordingly.

[0051] This invention also provides a gas field gathering and processing system, including a gathering system, a processing system, and a pressure regulating system. The pressure regulating system is used to dynamically reduce the operating pressure of the processing system as the total gas volume processed by the gathering and processing system gradually decreases, ensuring that the reduced operating pressure of the processing system is higher than and close to (slightly higher than) the minimum operating pressure of the processing system. Furthermore, during the dynamic reduction of the processing system's operating pressure, the system adjusts the pressurization scheme of the gathering and processing system to ensure that the pressurized pressure of the gathering and processing system is higher than and close to (slightly higher than) the operating pressure of the processing system, thereby minimizing the total pressurization production cost of the gathering and processing system.

[0052] Before dynamic pressurization, based on the current pressure and production of all gas wells in the gas field, and the future production and pressure of new and old gas wells, the production parameters of the gathering and processing system can be predicted for each time period. These parameters include the total pressurized gas volume of low-pressure wells in different pressure ranges, the total gas volume processed by the system, and the pressure distribution of gas wells. Based on the gas field's production decline and the gas field development professionals' predictions of well pressure and production, the minimum allowable operating pressure of the processing system, while still meeting the gas volume requirements, can be calculated. The pressure regulation system is also used to predict the total gas volume processed by the gathering and processing system for each time period of gas field production. Based on the total gas volume processed by the gathering and processing system for each time period, the minimum operating pressure of the processing system in each time period is determined. The operating pressure of the processing system is reduced in each time period, making the operating pressure infinitely higher than and close to the minimum operating pressure of that time period, and then maintained unchanged until the end of the time period. Reducing the operating pressure of the processing system can correspondingly reduce the energy consumption of the processing system.

[0053] In one embodiment, after reducing the operating pressure of the processing system, the pressure regulating system adjusts the pressurization method and pressure of the booster wells in the gathering and transportation system to ensure that the pressurized pressure of the gathering and transportation system is higher than and close to the operating pressure of the processing system, thereby minimizing the production cost of pressurized gathering and transportation. Specifically, after reducing the operating pressure of the processing system, the centralized booster outlet pressure of the gathering and transportation system is reduced to be higher than and close to the operating pressure of the processing system, and the centralized booster inlet pressure is reduced accordingly; when the pressure of a boosted well is greater than the operating pressure of the processing system after pressure reduction, pressurization of that boosted well is suspended; when the pressure of a boosted well using the single-well boosting method is greater than the adjusted operating pressure of the centralized booster inlet, the single-well boosting method is switched to the centralized boosting method; when the pressure of a boosted well using the single-well boosting method is still lower than the adjusted operating pressure of the centralized booster inlet, the single-well booster outlet pressure is reduced to be higher than and close to the operating pressure of the processing system.

[0054] Figure 2This is a structural block diagram of a gas field gathering and processing system provided in a typical embodiment of the present invention. Figure 2 As shown, in a typical embodiment, the gas field gathering and processing system includes a gathering system, a processing system, and a pressure regulation system. Figure 2 (Not shown). The gathering and transportation system includes a single-well site booster compressor 3, a single-well gas production pipeline 4, a centralized booster compressor 6, and a centralized booster gas collection pipeline 5. For gas wells with single-well site boosting, the single-well site booster compressor 3 is located within the gas well site 2 and is directly connected to the gas wellhead 1. For gas wells with centralized boosting, the two gas wellheads 1 are connected to the centralized booster gas collection pipeline 5 via the single-well gas production pipeline 4, and are connected to the inlet of the centralized booster compressor 6 via the centralized booster gas collection pipeline 5. The outlets of the centralized booster compressor 6 and the single-well site booster compressor 3 are connected to the production gas collection pipeline 7 via a gas transmission pipeline, and are connected to the processing system 8 via the production gas collection pipeline 7. The centralized booster compressor 6 and the processing system 8 are located within the gathering and transportation processing station 9.

[0055] As gas well production decreases, the total amount of gas entering processing system 8 gradually decreases. The pressure regulating system dynamically reduces the operating pressure of the processing system and correspondingly reduces the boosting pressure of the gathering and transportation system. For gas wells with single-wellfield boosting, the pressure regulating system reduces the boosting pressure on that gas well by lowering the outlet pressure of the single-wellfield boosting compressor 3 connected to the wellhead of that single gas well. For gas wells with centralized boosting, the pressure regulating system reduces the centralized boosting pressure by lowering the outlet pressure of the centralized boosting compressor 6 connected to the wellheads of two gas wells.

[0056] The gas field gathering and processing system in this embodiment adopts a dynamic pressurization scheme that combines pressurization gathering and depressurization processing. This reduces the operating pressure of the processing system while simultaneously reducing the pressurization pressure of the gathering and transportation system. This ensures that the pressurized pressure of the gathering and transportation system is infinitely higher than and close to the operating pressure of the processing system, thereby reducing the production energy consumption of the processing system and minimizing the production cost of pressurization gathering and transportation.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A dynamic pressurization method for a gas field gathering and processing system, the gathering and processing system comprising a gathering system and a processing system, characterized in that, The method includes: Predict the total gas volume processed by the gathering and processing system in each time period of gas field production, and determine the minimum operating pressure of the processing system in each time period based on the total gas volume processed by the gathering and processing system in each time period. Under the condition that the total gas volume processed by the gathering and transmission system gradually decreases, the operating pressure of the processing system is dynamically reduced, and the reduced operating pressure of the processing system is ensured to be higher than and close to the minimum operating pressure of the processing system. During the dynamic reduction of the operating pressure of the processing system, the pressurization scheme of the gathering and transportation system is adjusted to reduce the total pressurization production cost of the gathering and transportation system. Specifically, this includes: in each time period, after reducing the operating pressure of the processing system, reducing the centralized pressurization outlet pressure of the gathering and transportation system to a level higher than and close to the operating pressure of the processing system, and correspondingly reducing the centralized pressurization inlet pressure; suspending pressurization of the pressurized gas well when the pressure of the pressurized gas well is greater than the operating pressure of the processing system after pressure reduction; and switching the single-well pressurization mode to the centralized pressurization mode when the pressure of the pressurized gas well pressurized using the single-well pressurization method is greater than the adjusted operating pressure of the centralized pressurization inlet.

2. The dynamic pressurization method for a gas field gathering and processing system according to claim 1, characterized in that, The method of dynamically reducing the operating pressure of the processing system under the condition that the total gas volume processed by the gathering and transmission system gradually decreases includes: The operating pressure of the processing system is reduced in each time period, so that the operating pressure in each time period is higher than and close to the lowest operating pressure in that time period, and the operating pressure is kept constant until the end of the time period.

3. The dynamic pressurization method for the gas field gathering and processing system according to claim 1, characterized in that, The adjustment of the pressurization scheme of the gathering and transportation system during the process of dynamically reducing the operating pressure of the processing system also includes: If the pressure of a pressurized gas well using the single-well pressurization method is still lower than the adjusted operating pressure of the centralized pressurization inlet, reduce the single-well pressurization outlet pressure to be higher than and close to the operating pressure of the processing system.

4. A gas field gathering, transportation, and processing system, comprising a gathering and transportation system and a processing system, characterized in that, Also includes: The pressure regulation system is used to predict the total gas volume processed by the gathering and transportation system in each time period of gas field production. Based on the total gas volume processed in each time period, it determines the minimum operating pressure of the processing system in each time period. Under the condition that the total gas volume processed by the gathering and transportation system gradually decreases, it dynamically reduces the operating pressure of the processing system, ensuring that the reduced operating pressure is higher than and close to the minimum operating pressure of the processing system. During the dynamic reduction of the processing system's operating pressure, it adjusts the pressurization scheme of the gathering and transportation system to reduce the total pressurization production cost of the gathering and transportation system. This includes: in each time period, after reducing the operating pressure of the processing system, reducing the centralized pressurization outlet pressure of the gathering and transportation system to a level higher than and close to the operating pressure of the processing system, and correspondingly reducing the centralized pressurization inlet pressure; suspending pressurization of the pressurized gas well when the pressure of the pressurized gas well is greater than the reduced operating pressure of the processing system; and switching the single-well pressurization mode to the centralized pressurization mode when the pressure of the pressurized gas well using the single-well pressurization method is greater than the adjusted operating pressure of the centralized pressurization inlet.

5. The gas field gathering and processing system according to claim 4, characterized in that, The gathering and transportation system includes a single-well field booster compressor connected to a single gas wellhead and a centralized booster compressor connected to multiple gas wellheads. The outlets of the centralized booster compressor and the single-well field booster compressor are connected to the processing system through production gas collection pipelines. For gas wells with single-well field pressurization, the pressure regulation system reduces the pressurization pressure on the gas well by lowering the outlet pressure of the single-well field pressurization compressor connected to the wellhead of the single gas well. For gas wells with centralized pressurization, the pressure regulation system reduces the centralized pressurization pressure by lowering the outlet pressure of the centralized pressurization compressor connected to multiple gas wellheads.

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