Method and device for predicting elemental sulfur deposition in a gathering pipeline

Abstract

The application provides a prediction method and device for elemental sulfur deposition in a gathering pipeline. The prediction method for elemental sulfur deposition in the gathering pipeline comprises the following steps: determining the pipeline position where elemental sulfur deposition occurs according to the elemental sulfur content and the flow rate of natural gas in the pipeline; dividing the pipeline where elemental sulfur deposition occurs into multiple sub-pipelines according to flow parameters and working condition operation parameters; and respectively predicting the elemental sulfur deposition conditions of the multiple sub-pipelines according to the carrying coefficients and distribution coefficients of the multiple sub-pipelines. The application can accurately determine and predict the position where elemental sulfur deposition occurs in the ground gathering system pipeline under certain working conditions and the corresponding deposition amount. Moreover, the method is simple to calculate and closely combined with engineering practice, thereby providing strong technical support for safe, economic and efficient development of sulfur-containing gas wells.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field development technology, particularly to the field of sulfur-containing oil and gas field development technology, and specifically to a method and apparatus for predicting elemental sulfur deposition in a surface gathering and transportation system for sulfur-containing gas fields. Background Technology

[0002] Sulfur-bearing gas reservoirs are widely distributed worldwide. For example, the Puguang, Luojiazhai, and Dukouhe gas fields in the Sichuan Basin are all ultra-high sulfur-bearing gas fields. The presence of hydrogen sulfide in sulfur-bearing gas reservoirs causes significant differences in the physical properties of the extracted natural gas compared to conventional natural gas. Under original geological conditions, elemental sulfur usually exists as hydrogen sulfide or combines with hydrogen sulfide to form polysulfides. Polysulfides and elemental sulfur, as well as hydrogen sulfide, can interconvert, as shown in the following equation:

[0003]

[0004] As gas wells are extracted, the radial pressure at the bottom of the well decreases. During the flow of natural gas from the formation to the bottom of the well, carrying hydrogen polysulfides, as it passes through the decreasing pressure and temperature gradient profile of the formation, the equilibrium in the above equation shifts to the left. The hydrogen polysulfides carried by the natural gas decompose, releasing elemental sulfur. After the gas reservoir is put into development, the formation pressure and temperature continuously decrease radially over time. With these changes in temperature and pressure, the produced gas undergoes a phase transition. When the sulfur saturation level is reached or exceeded, elemental sulfur is released from the gas. If the elemental sulfur cannot be carried away by the gas flow, sulfur deposition occurs.

[0005] Elemental sulfur deposits in pipelines or equipment of ground gathering and transportation systems can have serious impacts on production. Specifically: deposits on valves or flow devices affect the accuracy of metering instruments; deposits at flanges, tees, or elbows may cause pipeline blockages and gas supply interruptions; deposits can cause pressure gauges to rise to warning values, thereby triggering a chain shutdown; and elemental sulfur deposits on the inner walls of pipelines and equipment can accelerate material corrosion.

[0006] In summary, elemental sulfur deposition in gathering and transportation pipelines poses a significant safety hazard, severely impacting the safe and efficient production of gas fields. Therefore, there is an urgent need for a method to predict elemental sulfur deposition in surface gathering and transportation systems for sulfur-containing gas wells. This method should be able to predict the likelihood of elemental sulfur deposition within the system, as well as its distribution location and deposition volume. This is crucial for the safe and efficient development of high-sulfur gas wells. Summary of the Invention

[0007] To address the problems in existing technologies, the present invention provides a method and apparatus for predicting elemental sulfur deposition in gathering and transportation pipelines. This method can accurately determine and predict the location and corresponding amount of elemental sulfur deposition within the pipelines of a surface gathering and transportation system under certain operating conditions. Furthermore, the method is computationally simple and closely integrated with practical engineering applications, thus providing strong technical support for the safe, economical, and efficient development of sulfur-containing gas wells.

[0008] In a first aspect, the present invention provides a method for predicting elemental sulfur deposition in gathering and transportation pipelines, comprising:

[0009] The location of elemental sulfur deposition in the pipeline is determined based on the elemental sulfur content and flow rate of the natural gas in the pipeline.

[0010] Based on flow parameters and operating conditions, the pipelines where elemental sulfur deposition occurs are divided into multiple sub-pipelines.

[0011] The elemental sulfur deposition in the multiple sub-channels is predicted based on their carrying capacity and distribution coefficient.

[0012] In one embodiment, determining the location of elemental sulfur deposition in the pipeline based on the elemental sulfur content and flow rate of the natural gas in the pipeline includes:

[0013] Measure the current temperature and pressure in the pipeline;

[0014] The elemental sulfur solubility in the pipeline is calculated based on the temperature and pressure.

[0015] The location of the pipeline where elemental sulfur deposition occurs is determined based on the elemental sulfur content, the elemental sulfur solubility, and the natural gas flow rate.

[0016] In one embodiment, the pipeline where elemental sulfur deposition occurs is divided into multiple sub-pipelines based on flow parameters and operating parameters, including:

[0017] The locations where the flow parameters and operating parameters change are set as the boundaries of the multiple sub-pipelines.

[0018] In one embodiment, the method for predicting elemental sulfur deposition in gathering and transportation pipelines further includes:

[0019] The carrying coefficient is determined based on the natural gas flow velocity in the sub-pipeline and the critical flow velocity.

[0020] The distribution coefficient is determined based on the carrying coefficient.

[0021] In one embodiment, predicting the elemental sulfur deposition in the plurality of sub-channels based on their carrying capacity and distribution coefficients includes:

[0022] The amount of elemental sulfur deposited in the sub-pipeline is determined based on the elemental sulfur content and solubility of the natural gas in the sub-pipeline, the carrying coefficient, and the distribution coefficient.

[0023] Secondly, the present invention provides a device for predicting elemental sulfur deposition in gathering and transportation pipelines, the device comprising:

[0024] The pipeline location determination module is used to determine the location of pipelines where elemental sulfur deposition occurs based on the elemental sulfur content of natural gas in the pipeline and the natural gas flow rate.

[0025] The pipeline segmentation module is used to divide pipelines where elemental sulfur deposition occurs into multiple sub-pipelines based on flow parameters and operating conditions.

[0026] The elemental sulfur deposition prediction module is used to predict the elemental sulfur deposition in the multiple sub-pipes based on their carrying coefficients and distribution coefficients.

[0027] In one embodiment, the pipeline location determination module includes:

[0028] Temperature and pressure measurement unit, used to measure the current temperature and pressure in the pipeline;

[0029] A solubility calculation unit is used to calculate the elemental sulfur solubility in the pipeline based on the temperature and pressure.

[0030] The pipeline location determination unit is used to determine the pipeline location where elemental sulfur deposition occurs based on the elemental sulfur content, the elemental sulfur solubility, and the natural gas flow rate.

[0031] In one embodiment, the pipeline segmentation module includes:

[0032] The boundary line determination unit is used to set the locations where the flow parameters and operating parameters change as the boundary lines of the multiple sub-pipelines.

[0033] In one embodiment, the device for predicting elemental sulfur deposition in the gathering and transportation pipeline further includes:

[0034] The carrying capacity determination module is used to determine the carrying coefficient based on the natural gas flow rate and critical flow rate of the sub-pipeline.

[0035] The distribution coefficient determination module is used to determine the distribution coefficient based on the carrying coefficient.

[0036] In one embodiment, the elemental sulfur deposition prediction module includes:

[0037] The elemental sulfur deposition determination unit is used to determine the elemental sulfur deposition in the sub-pipeline based on the elemental sulfur content and solubility of the natural gas in the sub-pipeline, the carrying coefficient, and the distribution coefficient.

[0038] Thirdly, the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of a method for predicting elemental sulfur deposition in a gathering and transportation pipeline.

[0039] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of a method for predicting elemental sulfur deposition in a gathering and transportation pipeline.

[0040] As can be seen from the above description, the method and apparatus for predicting elemental sulfur deposition in gathering and transportation pipelines provided in this embodiment of the invention first determines the pipeline location where elemental sulfur deposition occurs based on the elemental sulfur content and natural gas flow rate in the pipeline; then, the pipeline where elemental sulfur deposition occurs is divided into multiple sub-pipelines based on flow parameters and operating parameters; finally, the elemental sulfur deposition situation of the multiple sub-pipelines is predicted based on the carrying coefficient and distribution coefficient of the multiple sub-pipelines respectively.

[0041] This invention collects basic data such as the process flow and equipment operating parameters of the surface gathering and transportation system. First, it predicts the occurrence of elemental sulfur deposition by comparing the content and solubility of elemental sulfur in the produced natural gas, as well as the gas flow rate and the critical flow rate capable of carrying away precipitated elemental sulfur. If deposition is predicted, a carrying coefficient is further introduced to calculate the deposition distribution of elemental sulfur in different sections. This invention can accurately determine and predict the location and amount of elemental sulfur deposition within the pipeline of a surface gathering and transportation system under certain operating conditions. Furthermore, the method is simple to calculate and closely integrated with engineering practice, thus providing strong technical support for the safe, economical, and efficient development of sulfur-containing gas wells. Attached Figure Description

[0042] 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.

[0043] Figure 1 This is a schematic diagram of the structure of the prediction system for elemental sulfur deposition in the gathering and transportation pipeline in an embodiment of the present invention. Figure 1 ;

[0044] Figure 2 This is a schematic diagram of the structure of the prediction system for elemental sulfur deposition in the gathering and transportation pipeline in an embodiment of the present invention. Figure 2 ;

[0045] Figure 3This is a flowchart illustrating the method for predicting elemental sulfur deposition in gathering and transportation pipelines according to an embodiment of the present invention. Figure 1 ;

[0046] Figure 4 This is a flowchart illustrating step 100 in an embodiment of the present invention;

[0047] Figure 5 This is a flowchart illustrating step 200 in an embodiment of the present invention;

[0048] Figure 6 This is a flowchart illustrating the method for predicting elemental sulfur deposition in gathering and transportation pipelines according to an embodiment of the present invention. Figure 2 ;

[0049] Figure 7 This is a flowchart illustrating the method for predicting elemental sulfur deposition in gathering and transportation pipelines according to an embodiment of the present invention. Figure 3 ;

[0050] Figure 8 This is a flowchart illustrating step 300 in an embodiment of the present invention;

[0051] Figure 9 This is a flowchart illustrating the method for predicting elemental sulfur deposition in a gathering and transportation pipeline in a specific application example of the present invention.

[0052] Figure 10 This is a schematic diagram of the gathering and transportation pipeline in a specific application example of the present invention;

[0053] Figure 11 This is a schematic diagram of the structure of the prediction device for elemental sulfur deposition in the gathering and transportation pipeline in an embodiment of the present invention. Figure 1 ;

[0054] Figure 12 This is a schematic diagram of the pipeline location determination module 10 in the prediction device for elemental sulfur deposition in the gathering and transportation pipeline in an embodiment of the present invention;

[0055] Figure 13 This is a schematic diagram of the structure of the pipeline division module 20 in the prediction device for elemental sulfur deposition in the gathering and transportation pipeline in an embodiment of the present invention;

[0056] Figure 14 This is a schematic diagram of the structure of the prediction device for elemental sulfur deposition in the gathering and transportation pipeline in an embodiment of the present invention. Figure 2 ;

[0057] Figure 15 This is a schematic diagram of the elemental sulfur deposition prediction module 30 in the elemental sulfur deposition prediction device in the gathering and transportation pipeline in an embodiment of the present invention;

[0058] Figure 16 This is a schematic diagram of the structure of an electronic device in an embodiment of the present invention.

[0059] Icon labels:

[0060] 1: Wellhead;

[0061] 2: Water-jacketed heating furnace;

[0062] 3: First single well;

[0063] 4: Second single well;

[0064] 5: Check valve;

[0065] 6: Ball valve;

[0066] 7: Gas-liquid separator;

[0067] 8: Filter separator. Detailed Implementation

[0068] 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.

[0069] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0070] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product or device.

[0071] This application also provides a prediction system for elemental sulfur deposition in gathering and transportation pipelines, see [link to relevant documentation]. Figure 1 The system can be a server A1, which can communicate with multiple elemental sulfur content measuring components and natural gas flow rate measuring component B1. Server A1 can also communicate with multiple databases, or as... Figure 2 As shown, these databases can also be set up directly on server A1. The elemental sulfur content measuring component and the natural gas flow rate measuring component B1 are used to measure the elemental sulfur content and natural gas flow rate of the natural gas in the gathering and transportation pipeline, and send the measurement results to server A1. After receiving the elemental sulfur content and natural gas flow rate, server A1 predicts the elemental sulfur deposition situation in each sub-pipeline of the gathering and transportation pipeline.

[0072] It is understandable that client C1 can include smartphones, tablets, set-top boxes, laptops, desktops, personal digital assistants (PDAs), in-vehicle devices, and smart wearable devices. Among these, smart wearable devices can include smart glasses, smartwatches, and smart bracelets.

[0073] In practical applications, the part predicting elemental sulfur deposition in the sub-pipeline can be executed on server A1 as described above, i.e., as... Figure 1 or Figure 2 The architecture shown can also be implemented entirely within the client C1 device. The choice can be made based on the processing power of the client device and the limitations of the user's usage scenario. This application does not impose any limitations on this. If all operations are performed on the client device, the client device may also include a processor for operations such as predicting the elemental sulfur deposition status of the sub-pipelines.

[0074] The aforementioned client C1 device may have a communication module (i.e., a communication unit) that can communicate with a remote server to achieve data transmission. The server may include a server on one side that predicts the elemental sulfur deposition in the sub-pipeline; in other implementation scenarios, it may also include a server on an intermediate platform, such as a server on a third-party server platform that has a communication link with the server predicting the elemental sulfur deposition in the sub-pipeline. The server may include a single computer device, a server cluster consisting of multiple servers, or a distributed server structure.

[0075] The server and client devices can communicate using any suitable network protocol, including those not yet developed as of the date of this application. Network protocols may include, for example, TCP / IP, UDP / IP, HTTP, HTTPS, etc. Of course, network protocols may also include, for example, RPC (Remote Procedure Call Protocol) and REST (Representational State Transfer) protocols used on top of the aforementioned protocols.

[0076] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0077] See Figure 3 The present invention provides a specific implementation of a method for predicting elemental sulfur deposition in gathering and transportation pipelines, the method specifically including the following:

[0078] Step 100: Determine the location of the pipeline where elemental sulfur deposits occur based on the elemental sulfur content of the natural gas in the pipeline and the natural gas flow rate.

[0079] In the existing production environment of gathering and transportation pipelines, the process flow and equipment involved along the gathering and transportation system are not entirely the same. The operating pressure, temperature, and flow state at different locations are quite complex, and it involves gas-solid phase equilibrium, sulfur particle nucleation, production kinetics, and gas-solid multiphase flow problems accompanying changes in the gas-solid phase of elemental sulfur. Therefore, there is no clear and unified prediction method for the prediction and deposition of elemental sulfur within the gathering and transportation system. On the other hand, the equipment, specifications, and operating conditions of different process sub-sections of the surface gathering and transportation system are not entirely the same. When predicting and calculating the deposition of elemental sulfur, it is necessary to make some assumptions or idealizations of some operating condition parameters that closely fit the actual engineering production. Therefore, the existing prediction methods and results have certain deviations from actual production and have limitations in their application in actual engineering fields for the development of sulfur-containing gas fields.

[0080] Specifically, in step 100, when determining the location of the pipe where elemental sulfur deposition occurs, the following two conditions need to be considered (and satisfied simultaneously):

[0081] 1. The elemental sulfur content in the extracted natural gas is greater than the elemental sulfur solubility under the same temperature and pressure conditions;

[0082] 2. The gas velocity at this location is less than the critical velocity required to carry away the precipitated elemental sulfur particles under the same temperature and pressure conditions.

[0083] Step 200: Based on the flow parameters and operating parameters, the pipeline where elemental sulfur deposition occurs is divided into multiple sub-pipelines.

[0084] The principle of division is to classify two nodes whose flow parameters and operating parameters do not fluctuate significantly as a sub-pipeline. For example, the state of the fluid transported in equipment such as gas-liquid separators and filter separators changes significantly from the inlet to the outlet, and it is necessary to divide it into a separate sub-pipeline.

[0085] Step 300: Predict the elemental sulfur deposition in the multiple sub-pipes based on their carrying coefficients and distribution coefficients.

[0086] Based on step 100, if it is determined that elemental sulfur will be deposited in the gathering and transportation system pipeline, the amount of deposit in each sub-pipeline is further calculated.

[0087] As can be seen from the above description, the method for predicting elemental sulfur deposition in gathering and transportation pipelines provided in this embodiment of the invention first determines the location of the pipeline where elemental sulfur deposition occurs based on the elemental sulfur content and flow velocity of the natural gas in the pipeline; then, the pipeline where elemental sulfur deposition occurs is divided into multiple sub-pipelines based on flow parameters and operating parameters; finally, the elemental sulfur deposition situation of the multiple sub-pipelines is predicted based on the carrying coefficient and distribution coefficient of the multiple sub-pipelines respectively.

[0088] To address the potential precipitation and deposition of elemental sulfur in the surface gathering and transportation systems of sulfur-bearing gas fields, this invention, after predicting the occurrence of deposition through calculation, can further calculate the location and magnitude of the deposition. The method provided by this invention is simple to calculate, and the results are closely integrated with engineering practice. It can effectively calculate locations in the gathering and transportation system where deposition is highly likely. Operators can adjust process parameters accordingly based on the calculations to avoid cascading shutdowns of certain surface process sections or equipment due to exceeding warning values, thus preventing unnecessary unblocking operations or even well shutdowns. This provides strong technical support for the safe, economical, and efficient development of sulfur-bearing gas fields.

[0089] In one embodiment, see Figure 4 Step 100 includes:

[0090] Step 101: Measure the current temperature and pressure in the pipeline;

[0091] Step 102: Calculate the elemental sulfur solubility in the pipeline based on the temperature and pressure;

[0092] It is understandable that the solubility of elemental sulfur varies under different temperatures and pressures, so it is necessary to measure the current temperature and pressure of the pipeline and calculate the current solubility of elemental sulfur in the pipeline.

[0093] Step 103: Determine the location of the pipeline where elemental sulfur deposition occurs based on the elemental sulfur content, the elemental sulfur solubility, and the natural gas flow rate.

[0094] When the elemental sulfur content in natural gas is greater than the elemental sulfur solubility under the current conditions (same temperature and pressure), it is considered that elemental sulfur deposition may occur at this pipeline location. Then, the relationship between the gas flow rate and the critical flow rate at which natural gas can carry away the precipitated elemental sulfur particles under the same temperature and pressure conditions is determined. If the gas flow rate is less than the critical flow rate at the corresponding location, elemental sulfur deposition will occur at that location.

[0095] In addition, the method for calculating the natural gas flow rate Qn corresponding to the operating temperature Tn and pressure Pn of the sub-section is as follows:

[0096]

[0097] Where Qn is the natural gas flow rate under the operating conditions of the sub-section, m 3 / d; Q0 is the natural gas flow rate under standard conditions, in m³. 3 / d (Natural gas metering standard conditions: 20℃, 0.101325MPa), m 3 / d; Tn is the operating temperature of the sub-section, °C; Pn is the operating pressure of the sub-section, MPa; Pa is the local atmospheric pressure, MPa; Z is the natural gas compressibility factor, dimensionless.

[0098] The method for calculating the natural gas flow velocity Vn in the sub-section is as follows:

[0099]

[0100] Where Vn is the natural gas flow velocity of the sub-section, m / s; Qn is the natural gas flow rate under the operating conditions of the sub-section, m³ / s. 3 / d; A is the cross-sectional area of ​​the pipe section, in meters. 2 Compare the flow velocity Vn in the sub-section with the critical flow velocity Vc that can carry away the precipitated sulfur particles in the sub-section. Vc is the critical flow velocity, a practical empirical value from engineering practice, ranging from 3 to 8 m / s.

[0101] In one embodiment, see Figure 5 Step 200 includes:

[0102] Step 201: The locations where the flow parameters and operating parameters change are set as the boundary lines of the multiple sub-pipelines.

[0103] Specifically, firstly, based on actual conditions such as on-site production and regular overhauls, the starting and ending points of the gathering and transportation system section where elemental sulfur deposition occurs are determined. Basic parameters such as the specific process flow and equipment conditions of the section between the starting and ending points, the gas composition of the produced natural gas, flow rate, and pipeline specifications are collected. Next, the entire section is divided into several sub-pipelines. The principle for this division is to group two nodes with no significant fluctuations in flow parameters and operating parameters into one sub-pipeline. The state of the fluid transported within equipment such as gas-liquid separators and filter separators changes significantly from inlet to outlet, requiring them to be classified as separate sub-pipelines.

[0104] In one embodiment, see Figure 6 The prediction of elemental sulfur deposition in gathering and transportation pipelines also includes:

[0105] Step 400: Determine the carrying coefficient based on the natural gas flow rate and critical flow rate in the sub-pipeline;

[0106] Specifically, when the natural gas flow velocity Vn in the sub-pipe is less than the critical flow velocity Vc, it means that some of the elemental sulfur precipitated in the corresponding sub-pipe will be deposited, while the rest will be carried away by the gas flow to the next sub-pipe. The formula for calculating the carryover coefficient F at this time is:

[0107]

[0108] Where F is the carry-over coefficient, with a value range of F = 0 to 1, dimensionless; Vn is the natural gas flow velocity in the sub-pipeline, m / s; Vc is the critical flow velocity, which is an actual empirical value in engineering, with a value range of Vc = 3 to 8 m / s; a is an undetermined coefficient, dimensionless, with a value range of a = 0.1 to 5.

[0109] When the natural gas flow rate Vn in the sub-section is greater than the critical flow rate Vc, the elemental sulfur precipitated in the sub-section will be washed away by the gas flow and will not be deposited in this sub-section. At this time, F = 1.

[0110] In one embodiment, see Figure 7 The prediction of elemental sulfur deposition in gathering and transportation pipelines also includes:

[0111] Step 500: Determine the distribution coefficient based on the carrying coefficient.

[0112] Specifically, the expression for calculating the distribution coefficient G is as follows:

[0113] G = 1 - F

[0114] Wherein, G is the distribution coefficient, with a value range of G = 0 to 1, and is dimensionless; F is the carry coefficient, with a value range of F = 0 to 1, and is dimensionless.

[0115] In one embodiment, see Figure 8 Step 300 includes:

[0116] Step 301: Determine the amount of elemental sulfur deposited in the sub-pipeline based on the elemental sulfur content and solubility of the natural gas in the sub-pipeline, the carrying coefficient, and the distribution coefficient.

[0117] The amount of elemental sulfur deposited, M, is calculated using the following formula:

[0118] M = (C n -C s )×Q n ×(1-F)

[0119] Where M represents the deposition amount of elemental sulfur in the sub-pipeline, in g / d; Cn represents the elemental sulfur content in natural gas sampled and measured upstream of the deposition starting point, obtained through on-site natural gas sampling and laboratory analysis, in g / m³. 3Cs represents the elemental sulfur solubility under the corresponding operating conditions of the sub-pipeline, obtained through laboratory measurements or calculations using empirical formulas, in g / m³. 3 Q0 represents the natural gas flow rate under standard metering conditions, in meters (m). 3 / d (Natural gas metering standard conditions: 20℃, 0.101325MPa), m 3 / d; F is the carryover coefficient, which is dimensionless.

[0120] To further illustrate this solution, the present invention also provides specific application examples of the method for predicting elemental sulfur deposition in gathering and transportation pipelines. These specific application examples include the following: [See details]. Figure 9 .

[0121] S1: Determine the starting and ending points of the sections where sedimentation occurs in the production site's gathering and transportation system.

[0122] Define the specific process flow and equipment details at the beginning and end of the sedimentation zone; divide the sedimentation zone into several sub-pipelines according to operating conditions, flow states, and other principles; collect the corresponding operating temperature / pressure, natural gas flow rate, pipeline specifications, etc. for each sub-pipeline.

[0123] The ground-based gathering and transportation process in the study area is as follows: Figure 10 As shown: There are three production wells (Well #1, Well #2, and Well #3) at the well site. After natural gas is extracted from the wellhead, it passes through a primary throttling valve and enters a water-jacketed furnace for heating. After heating in the water-jacketed furnace, it enters a secondary throttling valve. Following the secondary throttling valve are a pressure gauge, a target flow meter, a corrosion monitoring device, and a check valve. After passing through the check valve, the gas enters the manifold via a three-way valve. The gas from the three wells is then combined and transported to the gas gathering station via a gas gathering branch line, where gas-liquid separation is performed. Basic production data is collected from the site, including the gas volume Q of each of the three production wells. 01 Q 02 Q 03 .exist Figure 10 In the middle: 1: wellhead, 2: water jacket heating furnace, 3: first single well, 4: second single well, 5: one-way valve, 6: ball valve, 7: gas-liquid separator and 8: filter separator.

[0124] Based on the actual situation of the on-site shutdown and overhaul, it can be determined that elemental sulfur deposition occurred in the gathering and transportation system of one of the production wells. The specific deposition area is the section from the secondary throttle valve to the filter separator in the downstream gas gathering station. Starting from the secondary throttle valve, along the natural gas flow direction, elemental sulfur deposition of varying degrees and morphologies was observed at the secondary throttle valve, the target flow meter after the secondary throttle valve, the corrosion-resistant pad device, the check valve, the gas-liquid separator, and the filter separator.

[0125] Basic data and operating condition data of the elemental sulfur deposition zone were collected on site, as shown in Table 1:

[0126] Table 1. Parameters corresponding to different sub-pipeline nodes

[0127]

[0128] Based on the differences in operating conditions and flow states within the interval, it is divided into the following 4 sub-pipelines:

[0129] Sub-pipeline 1: Single-well pipeline segment

[0130] Sub-pipeline 2: Well site to gas gathering station section

[0131] Sub-pipeline 3: Gas-liquid separator section of gas gathering station

[0132] Sub-pipeline 4: Gas gathering station filter separator section

[0133] Single well production Q0 = 10 6 m 3

[0134] S2: Determine whether elemental sulfur deposition will occur in a certain sub-pipe of the gathering and transportation system.

[0135] If the following two conditions are met simultaneously: ① the elemental sulfur content Cn in the extracted natural gas is greater than the elemental sulfur solubility Cs under the same temperature and pressure conditions, and ② the gas flow velocity Vn at this location is less than the critical flow velocity Vc that can carry away the precipitated elemental sulfur particles under the same temperature and pressure conditions, then elemental sulfur deposition will occur in this sub-pipeline.

[0136] The elemental sulfur content (Cn) in the natural gas produced from a single well is 0.0141 g / m³. 3 (20℃, 0.101325MPa)

[0137] Elemental sulfur solubility Cs = 0.0001 g / m 3 (20℃, 0.101325MPa)

[0138] At this point, the elemental sulfur content Cn in the extracted natural gas is greater than the elemental sulfur solubility Cs in the process section.

[0139] The gas flow velocity corresponding to the sub-pipe was calculated, and the results are shown in Table 2.

[0140] Flow velocity V1 in sub-pipe 1:

[0141]

[0142] Flow velocity V2 in sub-pipe 2:

[0143]

[0144] Sub-pipe 3 flow velocity V3:

[0145]

[0146] Sub-pipe 4 flow velocity V4:

[0147]

[0148] In the above formula, the gas volume Q of each of the three production wells is... 01 Q 02 Q 03 10 4 m 3 Q0 = Q 01 +Q 02 +Q 03 Q0 is the port flow, 10 4 m 3 .

[0149] Table 2 Gas Flow Velocities Corresponding to Different Sub-pipes

[0150] 1 Single-well pipeline deposition section <![CDATA[V1<Vc]]> yes 2 Well site to gas gathering station pipeline <![CDATA[V2>Vc]]> no 3 Gas-liquid separator at gas gathering station <![CDATA[V3<Vc]]> yes 4 Gas gathering station filter separator <![CDATA[V4<Vc]]> yes

[0151] As shown in Table 2, some of the elemental sulfur precipitated in sub-pipe 1 will be deposited, while the rest will be carried downstream by the airflow; no elemental sulfur will be deposited in sub-pipe 2, as it will all be carried downstream by the airflow; some of the elemental sulfur precipitated in sub-pipe 3 will be deposited, while the rest will be carried downstream by the airflow; and some of the elemental sulfur precipitated in sub-pipe 4 will be deposited, while the rest will be carried downstream by the airflow.

[0152] S3: Calculate the amount of elemental sulfur deposited in the corresponding sub-pipe.

[0153] If step S2 predicts that elemental sulfur deposition will occur in the sub-pipe, then the amount of elemental sulfur deposition in this sub-pipe is further calculated. The calculation results are shown in Table 3.

[0154] Table 3. Carrying coefficient and distribution coefficient for each sub-pipeline

[0155] 1 Single-well pipeline deposition section yes <![CDATA[(V1 / Vc) a ]]> <![CDATA[1-(V1 / Vc) a ]]> 2 Well site to gas gathering station pipeline no <![CDATA[(V1 / Vc) a ]]> 0 3 Gas-liquid separator at gas gathering station yes <![CDATA[(V1 / Vc) a (V3 / Vc) a ]]> <![CDATA[(V1 / Vc) a [1-(V3 / Vc) a ]]]> 4 Gas gathering station filter separator yes 0 <![CDATA[(V1 / Vc) a (V3 / Vc) a ]]>

[0156] The amount of elemental sulfur deposited in the sub-pipeline, M, is calculated using the following formula, and the calculation results are shown in Table 4:

[0157] M = (C n -C s )×Q0×(1-F)

[0158] Where M represents the deposition amount of elemental sulfur in the sub-pipeline, in g / d; Cn represents the elemental sulfur content in natural gas sampled and measured upstream of the deposition starting point, obtained through on-site natural gas sampling and laboratory analysis, in g / m³. 3 Cs represents the elemental sulfur solubility under the corresponding operating conditions of the sub-pipeline, obtained through laboratory measurements or formula calculations, in g / m³. 3Q0 represents the natural gas flow rate under standard metering conditions, in meters (m). 3 / d (Natural gas metering standard conditions: 20℃, 0.101325MPa), m 3 / d; F is the carryover coefficient, which is dimensionless.

[0159] Table 4 Deposition Amount of Each Sub-Pipeline

[0160] 1 Single-well pipeline deposition section yes 1.4 2 Well site to gas gathering station pipeline no 0 3 Gas-liquid separator at gas gathering station yes 11.3 4 Gas gathering station filter separator yes 1.3

[0161] As can be seen from the above description, the method for predicting elemental sulfur deposition in gathering and transportation pipelines provided in this embodiment of the invention first determines the location of the pipeline where elemental sulfur deposition occurs based on the elemental sulfur content and flow velocity of the natural gas in the pipeline; then, the pipeline where elemental sulfur deposition occurs is divided into multiple sub-pipelines based on flow parameters and operating parameters; finally, the elemental sulfur deposition situation of the multiple sub-pipelines is predicted based on the carrying coefficient and distribution coefficient of the multiple sub-pipelines respectively.

[0162] To address the potential precipitation and deposition of elemental sulfur in the surface gathering and transportation systems of sulfur-bearing gas fields, this invention, after predicting the occurrence of deposition through calculation, can further calculate the location and magnitude of the deposition. The method provided by this invention is simple to calculate, and the results are closely integrated with engineering practice. It can effectively calculate locations in the gathering and transportation system where deposition is highly likely. Operators can adjust process parameters accordingly based on the calculations to avoid cascading shutdowns of certain surface process sections or equipment due to exceeding warning values, thus preventing unnecessary unblocking operations or even well shutdowns. This provides strong technical support for the safe, economical, and efficient development of sulfur-bearing gas fields.

[0163] Based on the same inventive concept, this application also provides a device for predicting elemental sulfur deposition in gathering and transportation pipelines, which can be used to implement the method described in the above embodiments, as described in the following embodiments. Since the principle of the device for predicting elemental sulfur deposition in gathering and transportation pipelines is similar to that of the method for predicting elemental sulfur deposition in gathering and transportation pipelines, the implementation of the device can refer to the implementation of the method for predicting elemental sulfur deposition in gathering and transportation pipelines, and will not be repeated. As used below, the terms "unit" or "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the system described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0164] Embodiments of the present invention provide a specific implementation of a predictive device for elemental sulfur deposition in gathering and transportation pipelines, capable of implementing a method for predicting elemental sulfur deposition in gathering and transportation pipelines. See [link to specific implementation details]. Figure 11 The device for predicting elemental sulfur deposition in gathering and transportation pipelines specifically includes the following components:

[0165] The pipeline location determination module 10 is used to determine the pipeline location where elemental sulfur deposition occurs based on the elemental sulfur content of natural gas in the pipeline and the natural gas flow rate.

[0166] Pipeline segmentation module 20 is used to divide pipelines where elemental sulfur deposition occurs into multiple sub-pipelines based on flow parameters and operating parameters.

[0167] The elemental sulfur deposition prediction module 30 is used to predict the elemental sulfur deposition in the multiple sub-pipes based on their carrying coefficients and distribution coefficients.

[0168] In one embodiment, see Figure 12 The pipeline location determination module 10 includes:

[0169] Temperature and pressure measuring unit 101 is used to measure the current temperature and pressure in the pipeline;

[0170] The solubility calculation unit 102 is used to calculate the elemental sulfur solubility in the pipeline based on the temperature and pressure.

[0171] The pipeline location determination unit 103 is used to determine the pipeline location where elemental sulfur deposition occurs based on the elemental sulfur content, the elemental sulfur solubility, and the natural gas flow rate.

[0172] In one embodiment, see Figure 13 The pipeline division module 20 includes:

[0173] Boundary line determination unit 201 is used to set the locations where the flow parameters and operating parameters change as the boundary lines of the multiple sub-pipelines.

[0174] In one embodiment, see Figure 14 The prediction device for elemental sulfur deposition in gathering and transportation pipelines also includes:

[0175] The carrying coefficient is determined by the carrying module 40 based on the natural gas flow rate and critical flow rate of the sub-pipeline.

[0176] The distribution coefficient determination module 50 is used to determine the distribution coefficient based on the carrying coefficient.

[0177] In one embodiment, see Figure 15 The elemental sulfur deposition prediction module 30 includes:

[0178] The elemental sulfur deposition determination unit 301 is used to determine the elemental sulfur deposition in the sub-pipeline based on the elemental sulfur content and elemental sulfur solubility of the natural gas in the sub-pipeline, the carrying coefficient, and the distribution coefficient.

[0179] As can be seen from the above description, the elemental sulfur deposition prediction device in the gathering and transportation pipeline provided in this embodiment of the invention first determines the pipeline location where elemental sulfur deposition occurs based on the elemental sulfur content of natural gas in the pipeline and the natural gas flow rate; then, it divides the pipeline where elemental sulfur deposition occurs into multiple sub-pipelines based on flow parameters and operating parameters; finally, it predicts the elemental sulfur deposition situation of multiple sub-pipelines based on the carrying coefficient and distribution coefficient of each sub-pipeline.

[0180] To address the potential precipitation and deposition of elemental sulfur in the surface gathering and transportation systems of sulfur-bearing gas fields, this invention, after predicting the occurrence of deposition through calculation, can further calculate the location and magnitude of the deposition. The method provided by this invention is simple to calculate, and the results are closely integrated with engineering practice. It can effectively calculate locations in the gathering and transportation system where deposition is highly likely. Operators can adjust process parameters accordingly based on the calculations to avoid cascading shutdowns of certain surface process sections or equipment due to exceeding warning values, thus preventing unnecessary unblocking operations or even well shutdowns. This provides strong technical support for the safe, economical, and efficient development of sulfur-bearing gas fields.

[0181] This application also provides a specific implementation of an electronic device capable of implementing all steps in the prediction method for elemental sulfur deposition in gathering and transportation pipelines described in the above embodiments. See [link to implementation details]. Figure 16 The electronic devices specifically include the following:

[0182] Processor 1201, memory 1202, communications interface 1203, and bus 1204;

[0183] The processor 1201, memory 1202, and communication interface 1203 communicate with each other via bus 1204; the communication interface 1203 is used to realize information transmission between server-side devices, measuring devices, and user-side devices and other related devices.

[0184] The processor 1201 is used to call the computer program in the memory 1202. When the processor executes the computer program, it implements all the steps in the prediction method for elemental sulfur deposition in the gathering and transportation pipeline in the above embodiment. For example, when the processor executes the computer program, it implements the following steps:

[0185] Step 100: Determine the location of elemental sulfur deposition in the pipeline based on the elemental sulfur content and flow rate of the natural gas in the pipeline;

[0186] Step 200: Divide the pipeline where elemental sulfur deposition occurs into multiple sub-pipelines based on flow parameters and operating conditions;

[0187] Step 300: Predict the elemental sulfur deposition in the multiple sub-pipes based on their carrying coefficients and distribution coefficients.

[0188] Embodiments of this application also provide a computer-readable storage medium capable of implementing all steps of the prediction method for elemental sulfur deposition in gathering and transportation pipelines in the above embodiments. The computer-readable storage medium stores a computer program that, when executed by a processor, implements all steps of the prediction method for elemental sulfur deposition in gathering and transportation pipelines in the above embodiments. For example, when the processor executes the computer program, it implements the following steps:

[0189] Step 100: Determine the location of elemental sulfur deposition in the pipeline based on the elemental sulfur content and flow rate of the natural gas in the pipeline;

[0190] Step 200: Divide the pipeline where elemental sulfur deposition occurs into multiple sub-pipelines based on flow parameters and operating conditions;

[0191] Step 300: Predict the elemental sulfur deposition in the multiple sub-pipes based on their carrying coefficients and distribution coefficients.

[0192] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. In particular, hardware + program embodiments are relatively simple in description because they are fundamentally similar to method embodiments; relevant parts can be referred to the descriptions in the method embodiments.

[0193] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0194] While this specification provides method operation steps as described in the embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-inventive means. The order of steps listed in the embodiments is merely one possible execution order among many and does not represent the only execution order. In actual device or end product execution, the methods shown in the embodiments or drawings may be executed sequentially or in parallel (e.g., in a parallel processor or multi-threaded processing environment, or even a distributed data processing environment). The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, product, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, product, or apparatus. Without further limitations, the presence of other identical or equivalent elements in the process, method, product, or apparatus that includes said elements is not excluded.

[0195] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for predicting elemental sulfur deposition in gathering and transportation pipelines, characterized in that, include: The location of elemental sulfur deposition in the pipeline is determined based on the elemental sulfur content and flow rate of the natural gas in the pipeline. Based on flow parameters and operating conditions, the pipelines where elemental sulfur deposition occurs are divided into multiple sub-pipelines. The elemental sulfur deposition in the multiple sub-channels is predicted based on their carrying capacity and distribution coefficient. The carrying coefficient is determined based on the natural gas flow velocity in the sub-pipeline and the critical flow velocity. The distribution coefficient is determined based on the carrying coefficient; The method of determining the pipeline location where elemental sulfur deposition occurs based on the elemental sulfur content and flow rate of natural gas in the pipeline includes: Measure the current temperature and pressure in the pipeline; The elemental sulfur solubility in the pipeline is calculated based on the temperature and pressure. The location of the pipeline where elemental sulfur deposition occurs is determined based on the elemental sulfur content, the elemental sulfur solubility, and the natural gas flow rate. The method of predicting the elemental sulfur deposition in multiple sub-channels based on their carrying capacity and distribution coefficients includes: The amount of elemental sulfur deposited in the sub-pipeline is determined based on the elemental sulfur content and solubility of natural gas in the sub-pipeline, the carrying coefficient, and the distribution coefficient. When the natural gas flow velocity Vn in the sub-pipeline is less than the critical flow velocity Vc, the formula for calculating the carryover coefficient F is: Where F is the carry-over coefficient, with a value range of F=0~1, dimensionless; Vn is the natural gas flow velocity in the sub-pipeline, m / s; Vc is the critical flow velocity, which is an actual empirical value in engineering, with a value range of Vc=3~8m / s; a is an undetermined coefficient, dimensionless, with a value range of a=0.1~5; When the natural gas flow velocity Vn in the sub-section is greater than the critical flow velocity Vc, F=1; The expression for calculating the distribution coefficient G is: Wherein, G is the distribution coefficient, which ranges from G=0 to 1 and is dimensionless; The formula for calculating the elemental sulfur deposition M in the sub-pipeline is: Where M represents the deposition amount of elemental sulfur in the sub-pipeline, in g / d; Cn represents the elemental sulfur content in natural gas sampled and measured upstream of the deposition starting point, obtained through on-site natural gas sampling and laboratory analysis, in g / m³. 3 Cs represents the elemental sulfur solubility under the corresponding operating conditions of the sub-pipeline, obtained through laboratory measurements or formula calculations, in g / m³. 3 Q0 represents the natural gas flow rate under standard metering conditions, in meters (m). 3 / d; F is the carryover coefficient, which is dimensionless.

2. The method for predicting elemental sulfur deposition in gathering and transportation pipelines according to claim 1, characterized in that, The pipeline where elemental sulfur deposition occurs is divided into multiple sub-pipelines based on flow parameters and operating conditions, including: The locations where the flow parameters and operating parameters change are set as the boundaries of the multiple sub-pipelines.

3. A device for predicting elemental sulfur deposition in gathering and transportation pipelines, characterized in that, include: The pipeline location determination module is used to determine the location of pipelines where elemental sulfur deposition occurs based on the elemental sulfur content of natural gas in the pipeline and the natural gas flow rate. The pipeline segmentation module is used to divide pipelines where elemental sulfur deposition occurs into multiple sub-pipelines based on flow parameters and operating conditions. The elemental sulfur deposition prediction module is used to predict the elemental sulfur deposition in the multiple sub-pipes based on their carrying coefficients and distribution coefficients. The carrying capacity determination module is used to determine the carrying coefficient based on the natural gas flow rate and critical flow rate of the sub-pipeline. A distribution coefficient determination module is used to determine the distribution coefficient based on the carrying coefficient; The pipeline location determination module includes: Temperature and pressure measurement unit, used to measure the current temperature and pressure in the pipeline; A solubility calculation unit is used to calculate the elemental sulfur solubility in the pipeline based on the temperature and pressure. The pipeline location determination unit is used to determine the location of the pipeline where elemental sulfur deposition occurs based on the elemental sulfur content, the elemental sulfur solubility, and the natural gas flow rate. The elemental sulfur deposition prediction module includes: The elemental sulfur deposition determination unit is used to determine the elemental sulfur deposition in the sub-pipeline based on the elemental sulfur content and elemental sulfur solubility of the natural gas in the sub-pipeline, the carrying coefficient, and the distribution coefficient. When the natural gas flow velocity Vn in the sub-pipeline is less than the critical flow velocity Vc, the formula for calculating the carryover coefficient F is: Where F is the carry-over coefficient, with a value range of F=0~1, dimensionless; Vn is the natural gas flow velocity in the sub-pipeline, m / s; Vc is the critical flow velocity, which is an actual empirical value in engineering, with a value range of Vc=3~8m / s; a is an undetermined coefficient, dimensionless, with a value range of a=0.1~5; When the natural gas flow velocity Vn in the sub-section is greater than the critical flow velocity Vc, F=1; The expression for calculating the distribution coefficient G is: Wherein, G is the distribution coefficient, which ranges from G=0 to 1 and is dimensionless; The formula for calculating the elemental sulfur deposition M in the sub-pipeline is: Where M represents the deposition amount of elemental sulfur in the sub-pipeline, in g / d; Cn represents the elemental sulfur content in natural gas sampled and measured upstream of the deposition starting point, obtained through on-site natural gas sampling and laboratory analysis, in g / m³. 3 Cs represents the elemental sulfur solubility under the corresponding operating conditions of the sub-pipeline, obtained through laboratory measurements or formula calculations, in g / m³. 3 Q0 represents the natural gas flow rate under standard metering conditions, in meters (m). 3 / d; F is the carryover coefficient, which is dimensionless.

4. The device for predicting elemental sulfur deposition in gathering and transportation pipelines according to claim 3, characterized in that, The pipeline segmentation module includes: The boundary line determination unit is used to set the locations where the flow parameters and operating parameters change as the boundary lines of the multiple sub-pipelines.

5. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the method for predicting elemental sulfur deposition in a gathering and transportation pipeline as described in any one of claims 1 to 2.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the steps of the method for predicting elemental sulfur deposition in a gathering and transportation pipeline as described in any one of claims 1 to 2.

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