Offshore oil and gas field in-service facility capacity expansion, lifting and transportation evaluation method and system

Abstract

The invention relates to an offshore oil and gas field in-service facility capacity expansion, lifting and transportation evaluation method and system, and the method comprises the steps: receiving a capacity expansion, lifting and transportation task, and providing a basic principle which needs to be accorded with the capacity expansion, lifting and transportation of in-service production facilities through combining the characteristics of an offshore oil and gas field; according to a basic principle, determining an evaluation work range and evaluation work content of capacity expansion, lifting and transportation of offshore in-service facilities and a check calculation method of each facility, and generating a plurality of capacity expansion, lifting and transportation schemes for different systems; performing collaborative analysis on different systems, evaluating, feeding back and adjusting a plurality of capacity expansion lifting and transporting schemes based on a collaborative analysis result, eliminating infeasible capacity expansion lifting and transporting schemes, and generating a better capacity expansion lifting and transporting scheme; and reviewing the better capacity expansion and transportation lifting scheme, further optimizing the capacity expansion and transportation lifting scheme according to a reviewing result, and generating an optimal capacity expansion and transportation lifting scheme. According to the method, the condition of the in-service facility can be evaluated more scientifically and reasonably, and the research quality and efficiency of the capacity expansion, lifting and transportation scheme of the in-service facility of the offshore oil and gas field are effectively improved.

Description

Technical Field

[0001] The invention relates to a method and system for evaluating the capacity expansion and transportation of in-service facilities in offshore oil and gas fields, belonging to the technical field of offshore oil and gas field development engineering. Background Art

[0002] The exploitation and production of marine oil and gas fields is carried out at sea, and mid- and late-stage production increase measures are also carried out on offshore production facilities in service. Offshore production facilities have the characteristics of limited space and high cost. Not only will the implementation of production increase measures be affected, but the increase in production capacity will also be affected by the capacity expansion limit of production facilities.

[0003] For the increase in production in the middle and late stages of oil and gas field development, whether it is onshore or offshore, the relevant research starts from the aspects of reservoirs, drilling and completion, and conducts research on technical measures, capital investment and economic evaluation analysis methods. However, for the evaluation of ground or platform engineering facilities, there is only a summary and analysis of the implementation plans of specific engineering projects, which is scattered, random and inefficient, and there is no systematic method research. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a method and system for evaluating the capacity expansion and transportation of in-service facilities in offshore oil and gas fields. For the capacity expansion and transportation evaluation of in-service facilities in offshore oil and gas fields, the conditions of in-service facilities can be evaluated more scientifically and reasonably, and capacity expansion and transportation plans that meet technical specifications, are technically feasible, and economically reasonable can be proposed, thereby effectively improving the quality and efficiency of research on capacity expansion and transportation plans for in-service facilities in offshore oil and gas fields.

[0005] To achieve the above-mentioned purpose, the present invention proposes the following technical solutions: a method for evaluating the expansion of in-service facilities of offshore oil and gas fields, comprising the following steps: receiving a capacity expansion and transportation task, and proposing basic principles that the capacity expansion and transportation of in-service production facilities must comply with in combination with the characteristics of offshore oil and gas fields; determining the scope of evaluation work, evaluation work content and verification calculation method of each facility for the expansion of in-service offshore facilities based on the basic principles, and generating multiple capacity expansion and transportation plans for different systems; performing collaborative analysis on different systems, and based on the results of the collaborative analysis, evaluating, feeding back and adjusting the multiple capacity expansion and transportation plans, eliminating unfeasible capacity expansion and transportation plans, and generating a better capacity expansion and transportation plan; reviewing the better capacity expansion and transportation plan, and further optimizing the capacity expansion and transportation plan based on the review results to generate the best capacity expansion and transportation plan.

[0006] Furthermore, the basic principles are based on clear reservoir and drilling and production plans, the production status of existing production facilities, and in accordance with relevant laws, regulations, standards and specifications, taking into account the coordinated application of existing technologies and facilities with new technologies and new facilities, as well as the comprehensive generation of technical, economic, safety and environmental protection and energy-saving factors.

[0007] Furthermore, the scope of the evaluation work includes: evaluation of crude oil processing system, natural gas processing system, produced water treatment system, subsea pipeline transmission system, power supply and distribution system, platform space, platform structure and public support system; the capacity expansion and transmission plan includes technical solution analysis and economic analysis, and the technical solution analysis includes the expansion and transformation plan of the original equipment and the analysis of the new process or equipment plan; the economic analysis includes investment estimate and economic evaluation.

[0008] Furthermore, the evaluation work content and the verification calculation method of each facility are: oil, gas and water treatment capacity verification, submarine pipeline transportation capacity verification, key mechanical equipment capacity verification, power supply capacity verification, platform structure verification and public support system verification; the oil, gas and water treatment capacity verification includes: oil and gas treatment facility capacity evaluation; water treatment facility capacity evaluation and new oil, gas and water treatment facility plan analysis; the submarine pipeline transportation capacity verification includes: submarine pipeline process capacity evaluation, sea pipe and riser stress analysis, corrosion pit pipeline status evaluation and residual strength analysis and submarine pipeline corrosion evaluation; the key mechanical equipment capacity verification includes: reciprocating compressor capacity verification, centrifugal compressor capacity verification and centrifugal pump capacity verification; the power supply capacity verification includes: platform main power station analysis, regional power grid analysis and platform emergency power station analysis; the platform structure verification includes: design level evaluation, ultimate strength evaluation and platform structure corrosion analysis; the public support system verification includes: fuel system, cooling system, instrumentation and control system, power distribution system, public system, fire and gas system, fire protection system and piping system capacity evaluation.

[0009] Furthermore, the oil and gas processing facility capacity assessment and water treatment facility capacity assessment methods include: collecting original design data, construction completion data, platform previous modification data and current equipment and facility data; through the acquisition of the data and information, understanding the in-service oil and gas or water treatment process and comparing it with the data after the expansion and transmission is completed, confirming whether there are differences with the designed equipment and process, and the reasons for the differences; obtaining the operating parameters of the oil and gas processing process or the water treatment process during actual operation, and judging whether the operating parameters meet the design conditions and the designed treatment effect; if the treatment flow rate does not reach the design value and the actual treatment effect is good, it is considered that the equipment and treatment system are in good condition; if the treatment flow rate reaches the design value and the actual treatment effect is good, it is considered that the treatment process is suitable for the current design parameters; if the treatment flow rate does not reach the design value and the actual treatment effect fluctuates during operation, but the overall treatment effect can still meet the design requirements, consider coordinating on-site to adjust the injection point and concentration of chemical agents, test whether the treatment effect of the oil and gas or water treatment system is improved, and find out the restrictive factors in combination with the on-site operation situation, and carry out targeted transformation or add corresponding equipment.

[0010] Furthermore, the method for analyzing the plan for adding new oil, gas and water treatment facilities is as follows: after technical and economic analysis, if the design of the in-service treatment system is reasonable and the treatment process with good treatment effect is directly used; if after technical and economic analysis, there is a more suitable treatment process that meets the access requirements, the new facilities should adopt the new process in parallel with the original process; for the in-service production process with unstable treatment effect, analyze the reasons for its poor treatment effect, avoid this problem in the new treatment process, and check the treatment scale of the in-service treatment system according to its maximum treatment capacity that can ensure the treatment effect.

[0011] Furthermore, the method for evaluating the corrosion of submarine pipelines is as follows: basic data is collected, and when the CO2 / H2S partial pressure changes significantly compared with the design value, the uniform corrosion amount before expansion is calculated using actual production test data; when the CO2 / H2S partial pressure does not change significantly compared with the design value, the data before expansion is taken based on the original design report; based on the basic data and the intelligent internal detection results, the local corrosion rate before expansion is analyzed to evaluate the local corrosion risk of submarine pipelines; when more than two internal detection results are obtained, the historical local corrosion rate of typical defect points is quantitatively calculated; based on the detection and prediction of CO2 / H2S components and partial pressure values ​​in the gas phase, the change in the H2S corrosion cracking risk of in-service submarine pipelines is evaluated; based on the basic data, the current status of external corrosion of submarine pipelines and subsequent operation risks are qualitatively evaluated; based on the above corrosion prediction results and combined with the verification conclusions of the submarine pipeline structure, corrosion prevention and control measures such as process flow optimization, reagent adjustment, pigging strategy improvement, pipeline replacement and monitoring and detection schemes are proposed.

[0012] Furthermore, the method for verifying the capacity of key mechanical equipment includes: when the offshore facilities in service are expanded and transported, the process booster compressors and pumps are verified and evaluated, and attention is paid to the actual delivery capacity of reciprocating compressors, centrifugal compressors and centrifugal pumps; for reciprocating compressors with capacity impairment, if the actual delivery capacity cannot meet the expansion and transportation needs, the reason for the capacity impairment of the reciprocating compressor should be understood, and the actual processing capacity of the compressor should be determined; for working conditions where the capacity of the reciprocating compressor cannot meet the requirements, compressor modification or replacement, series connection, and parallel connection of new compressors should be considered; for centrifugal compressors, the compressor operating points are verified year by year according to the compressor performance curve in the completion document, and for working conditions where the centrifugal compressor capacity cannot meet the requirements, compressor core replacement, head replacement, replacement, series connection, and parallel connection of new compressors should be considered; for centrifugal pumps, attention is paid to whether the viscosity of the boosting medium changes, and the pump operating points are verified year by year according to the pump performance curve in the completion document; for working conditions where the capacity of the centrifugal pump cannot meet the requirements, replacement, series connection, and parallel connection of new pumps should be considered.

[0013] Furthermore, the method for verifying the power supply capacity includes: when the capacity of the offshore in-service facilities is expanded and the transmission is increased, the capacity of the existing main power station of the offshore oil and gas field is verified and evaluated, and during the verification, the power load demand of the oil field after the expansion and transmission is calculated based on the actual production load of the oil and gas field and the predicted increase in load; when the oil and gas field adopts gas turbine units for power supply, the regional gas balance is verified to ensure that there is sufficient fuel gas for power supply; the fuel oil / gas consumption required for the expansion and transmission of the in-service facilities is calculated, and this part of the impact is taken into account in the economic evaluation; if the existing power supply capacity of the oil and gas field is insufficient, it is necessary to consider adding a main power station based on the existing conditions of the platform, and at the same time verify the corresponding public system.

[0014] The present invention also discloses an offshore oil and gas field in-service facility expansion and transportation assessment system, comprising: a basic principle establishment module, used for receiving capacity expansion and transportation tasks, and combining the characteristics of offshore oil and gas fields to propose basic principles that the capacity expansion and transportation of in-service production facilities must comply with; a verification calculation module, used for determining the assessment work scope, assessment work content and verification calculation method of each facility for the capacity expansion and transportation of offshore in-service facilities according to the basic principles, and generating multiple capacity expansion and transportation schemes for different systems; a capacity expansion and transportation scheme optimization module, used for collaborative analysis of different systems, and based on the results of the collaborative analysis, evaluating, feeding back and adjusting the multiple capacity expansion and transportation schemes, eliminating unfeasible capacity expansion and transportation schemes, and generating a better capacity expansion and transportation scheme; a scheme review module, used for reviewing the better capacity expansion and transportation scheme, further optimizing the capacity expansion and transportation scheme according to the review results, and generating the best capacity expansion and transportation scheme. The technical solution of the present invention has at least the following technical effects or advantages: the solution of the present invention can achieve a more scientific and reasonable assessment of the status of in-service facilities, and propose a capacity expansion and transportation plan that meets technical specifications, is technically feasible, and economically reasonable, effectively improving the quality and efficiency of research on capacity expansion and transportation plans for in-service facilities in offshore oil and gas fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a flow chart of a method for evaluating the capacity expansion and transmission of in-service facilities in an offshore oil and gas field in one embodiment of the present invention; Figure 2 It is a flow chart of the capacity expansion and transmission assessment work of in-service facilities in offshore oil and gas fields in one embodiment of the present invention. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is described in detail through specific embodiments. However, it should be understood that the provision of specific embodiments is only for a better understanding of the present invention, and they should not be understood as limitations of the present invention. In the description of the present invention, it should be understood that the terms used are only for the purpose of description and cannot be understood as indicating or implying relative importance.

[0017] When offshore oil and gas fields increase production by drilling new wells, increasing the lifting capacity of lift pumps, etc., the existing engineering facilities in service need to expand their processing capacity and related support system capacity accordingly to the increased production, or understand it as the expansion of the facility's receiving capacity and the improvement of the ability to transport the treated crude oil outward. This process is referred to as "capacity expansion and transportation". In the present invention, in-service facilities should be understood as facilities in service, that is, facilities in use.

[0018] Aiming at the lack of a system in the existing technology for evaluating the expansion and transportation of in-service facilities of offshore oil and gas fields, the present invention provides an evaluation method for the expansion and transportation of in-service facilities of offshore oil and gas fields, obtains the demand for oilfield production increase and expansion and transportation, the status of the in-service facilities to be evaluated, and the corresponding technical specifications; combines the demand, status, and technical specifications to determine the scope of evaluation, evaluation principles, and systems involved in the evaluation; according to the evaluation principles, the systems involved are calculated, verified, and analyzed respectively, firstly a single system analysis is performed, and then a collaborative analysis is performed between different systems, and when necessary, a special study is carried out to eliminate technically unfeasible solutions and propose technically feasible solutions; investment estimation and economic analysis are carried out for technically feasible solutions to achieve investment and economic benchmark indicators, and finally a technically feasible and economically reasonable expansion and transportation solution is selected. The present invention can evaluate the status of in-service facilities more scientifically and reasonably with a complete process, rigorous principles, comprehensive and detailed calculation verification, and a comprehensive analysis combined with key factors, and then a capacity expansion and transportation solution that meets technical specifications, is technically feasible, and is economically reasonable can be proposed, which can effectively improve the quality and efficiency of the research on the capacity expansion and transportation solution of in-service facilities of offshore oil and gas fields. The present invention will be described in detail below through embodiments in conjunction with the accompanying drawings.

[0019] Embodiment 1 This embodiment discloses a method for evaluating the expansion of in-service facilities in offshore oil and gas fields. Figure 1 and Figure 2 As shown, the following steps are included: S1 receives the task of increasing oil field production and expanding capacity and transportation. Based on the characteristics of offshore oil and gas fields, it proposes the basic principles that must be followed in expanding the capacity and transportation of in-service production facilities.

[0020] The characteristics of offshore oil and gas fields include but are not limited to offshore oil and gas field production enhancement technology, production methods, marine environment, and various requirements and objectives.

[0021] The basic principles are based on clear reservoir and drilling and production plans, the production status of existing production facilities, and relevant laws, regulations, standards and specifications, with special attention to relevant new requirements; taking into account the coordinated application of existing technologies and facilities with new technologies and new facilities, and taking into account comprehensive factors such as technicality, economy, safety, environmental protection and energy conservation.

[0022] S2 determines the scope of assessment work on the expansion and improvement of capacity of in-service offshore facilities, the assessment work content and the verification and calculation methods for each facility based on basic principles, and generates multiple expansion and improvement plans for different systems.

[0023] The scope of the assessment work is the assessment work involved in the capacity expansion and transmission assessment of offshore facilities in service.

[0024] The assessment work includes the work content and specific verification and calculation methods of each system involved in the capacity expansion and transportation assessment of offshore in-service facilities. The scope of the assessment work includes: crude oil processing system, natural gas processing system, produced water treatment system, sea pipeline transmission system, power supply and distribution system, platform space, platform structure and public support system assessment; the capacity expansion and transportation plan includes technical solution analysis and economic analysis, and the technical solution analysis includes the expansion and transformation plan of the original equipment, the analysis of the new process or equipment plan (including the application of new technology); the economic analysis includes investment budget and economic evaluation.

[0025] The assessment work content and the verification calculation methods of each facility are as follows: verification of oil, gas and water treatment capacity, verification of submarine pipeline transportation capacity, verification of key mechanical equipment capacity, verification of power supply capacity, verification of platform structure and verification of public support system; The oil, gas and water treatment capacity verification includes: oil and gas treatment facility capacity assessment; water treatment facility capacity assessment and analysis of new oil, gas and water treatment facility plans; Submarine pipeline transportation capacity verification includes: submarine pipeline process capacity assessment, sea pipe and riser stress analysis, corrosion pit pipeline status evaluation and residual strength analysis, and submarine pipeline corrosion assessment; The capacity check of key mechanical equipment includes: capacity check of reciprocating compressor, capacity check of centrifugal compressor and capacity check of centrifugal pump; Power supply capacity verification includes: analysis of the platform main power station, regional power grid and platform emergency power station; Platform structure verification includes: design level assessment, ultimate strength assessment and platform structure anti-corrosion analysis; The verification of utility support systems includes: fuel system, cooling system, instrumentation and control system, power distribution system, utility system, fire and gas system, fire protection system and piping system capability assessment.

[0026] S3 conducts collaborative analysis of different systems, and based on the results of the collaborative analysis, evaluates, provides feedback and adjusts multiple capacity expansion and transmission plans, eliminates unfeasible capacity expansion and transmission plans, and generates a better capacity expansion and transmission plan.

[0027] In view of the reservoir plan and drilling and production plan for increasing oil field production, combined with an objective assessment of the current status of in-service facilities, we study and formulate technical plans for capacity expansion and transportation of engineering professionals, and conduct investment estimates and economic evaluations of the overall plan including reservoir plans, drilling and production plans, and engineering plans.

[0028] S4 reviews the better capacity expansion and transmission plans, further optimizes the capacity expansion and transmission plans based on the review results, and generates the best capacity expansion and transmission plan.

[0029] In this embodiment, the oil and gas processing facility capacity assessment method is: Collect original design data, construction completion data, platform previous modification data and current equipment and facility data; original design data include: design basis, relevant design drawings, design reports and equipment design parameters in the detailed design stage; construction completion data include: construction completion drawings, completion reports and platform equipment and facility operation manuals; platform previous modification data include: modification reasons, design drawings and reports after modification, parameters of new or replaced equipment, etc.; current equipment and facility data include: current oil, gas and water treatment facility operating parameters, operating conditions, equipment and facility status, on-site production demand collection, etc.

[0030] Through the acquisition of information and data, we can understand the in-service oil and gas processing process and facility selection principles and compare them with the data after the expansion and transportation is completed to confirm whether there are differences with the designed equipment and process, and determine the reasons for the differences; obtain the operating parameters of the oil and gas processing process during actual operation, such as on-site oil and gas separation, pressurization, heating parameters, daily production reports, etc. Determine whether the operating parameters meet the design conditions and design treatment effects.

[0031] According to the oil and gas processing flow and the corresponding equipment design processing capacity, the equipment with the smallest processing scale in the processing system is identified, and this is used as the theoretical processing scale of the oil and gas processing system for evaluation.

[0032] If the processing flow rate does not reach the design value, but the actual processing effect is good, and the equipment outlet oil content, gas liquid content, temperature, pressure and other indicators all meet the design requirements of the processing flow, then it is considered that the equipment and the processing system are in good condition, and the equipment processing capacity can be based on the design conditions. If conditions permit on site, it is better to increase the processing capacity to test the equipment operation effect.

[0033] For a treatment process where the treatment flow reaches the design value, the actual treatment effect is good, and the oil content at the equipment outlet, gas liquid content, temperature, and pressure all meet the design requirements, the treatment process is considered to be applicable to the current design parameters, and similar design foundations can be set as a reference.

[0034] If the processing flow rate does not reach the design value and the actual processing effect fluctuates during operation, but the overall processing effect can still meet the design requirements, consider coordinating on-site to adjust the chemical injection point and concentration, test whether the treatment effect of the oil and gas processing system is improved, and if possible increase the processing capacity to test the operating effect of the equipment. Combined with the on-site operation situation, find out the restrictive factors and make targeted modifications or add corresponding equipment.

[0035] For oil and gas treatment processes that have passed production verification and cannot reach the designed treatment indicators if a certain treatment volume is exceeded, the maximum liquid oil and gas treatment volume that ensures the treatment effect is used as the actual water treatment scale.

[0036] The water treatment facility capacity assessment method is: By acquiring information and data, we can understand the water treatment process in service and the selection principles of facilities, and compare them with the data after the expansion and transmission is completed to confirm whether there are differences with the designed equipment and processes, and determine the reasons for the differences; obtain the operating parameters of the water treatment process during actual operation, such as on-site oily wastewater testing data and other information, understand the operating parameters of the water treatment process during actual operation, and judge whether the operating parameters meet the design conditions and design treatment effects.

[0037] According to the water treatment process and the corresponding equipment design processing capacity, the equipment with the smallest processing scale in the treatment system is identified, and this is used as the theoretical processing scale of the water treatment system for evaluation.

[0038] For treatment processes where the treatment flow rate does not reach the design value but the actual treatment effect is good, and the oil content and suspended solids at the equipment outlet meet the design requirements, it is considered that the equipment and treatment system are in good condition, and the equipment processing capacity can be based on the design conditions. If conditions permit on site, it is better to increase the processing capacity to test the equipment operation effect.

[0039] For treatment processes where the treatment flow reaches the design value, the actual treatment effect is good, and the oil content and suspended solids at the equipment outlet meet the design requirements, the treatment process is considered to be applicable to the current design parameters, and similar design foundations can be set as a reference.

[0040] If the treatment flow rate does not reach the design value and the actual treatment effect fluctuates during operation, but the overall treatment effect can still meet the design requirements, consider coordinating on-site to adjust the chemical injection point and concentration, test whether the treatment effect of the water treatment system is improved, and if conditions permit, increase the treatment capacity to test the operation effect of the equipment. Combined with the on-site operation situation, find out the restrictive factors and make targeted modifications or add corresponding equipment.

[0041] For water treatment processes that have passed production verification and cannot reach the designed treatment indicators if the treatment volume exceeds a certain level, the maximum water treatment volume that can ensure the treatment effect is taken as the actual water treatment scale.

[0042] The logistics with similar oil products and design conditions rely on the in-service production water treatment process. The new water treatment facility plan can be designed according to the actual treatment effect of the in-service process and the platform conditions. The method for analyzing the new oil and gas water treatment facility plan is as follows: After technical and economic analysis, the treatment process with reasonable design and good treatment effect in the in-service treatment system will be directly used; The existing treatment system uses unique treatment equipment with good treatment effect, which conforms to the on-site operation habits. The water treatment process that meets the access requirements of the supporting project after technical and economic analysis can be considered to be used. If there is a more suitable treatment process that meets the access requirements after technical and economic analysis, the new facilities should adopt the new process in parallel with the original process; For existing production processes with unstable treatment effects, analyze the reasons leading to poor treatment effects, avoid this problem in new treatment processes, and calibrate the treatment scale of existing treatment systems according to their maximum treatment capacity that can ensure treatment effects.

[0043] When designing the treatment scale of new water treatment facilities, the annual water treatment needs of existing and new oil fields should be taken into consideration. The production allocation data of in-service oil fields have been verified by actual production, and the water volume fluctuation coefficient can be ignored when verifying the supporting capacity. For the production allocation of new oil fields, a certain water volume fluctuation coefficient should be considered according to the principles of each design stage to improve the adaptability of water treatment facilities to changes in production allocation; When verifying an in-service water treatment system with a backwash process, the actual processing capacity of the in-service water treatment facilities should include the processing capacity for backwash water.

[0044] The specific method for verifying the transmission capacity of submarine pipelines is as follows: Collect submarine pipeline data, including: original design data, such as the design basis, relevant design reports, design parameters, etc. in the detailed design stage; construction completion data, such as construction completion drawings, completion reports, platform equipment and facilities sea pipeline operation manuals, etc.; actual production oil properties; current sea pipeline transportation capacity, such as current operating conditions (temperature / pressure / flow rate, etc.), pipeline cleaning conditions, on-site production demand collection, etc.

[0045] The method for evaluating the process capability of submarine pipelines is: Through submarine pipeline data, we can understand the transportation principles of in-service oil pipelines, compare them with completion data, confirm whether there are differences between on-site transportation and design, understand the reasons for the differences, obtain on-site production daily reports and other information, understand the operating parameters during the actual transportation process, and whether the design conditions and design transportation capacity are met.

[0046] Based on the transportation capacity, the minimum output and scale of the pipeline are determined and used to carry out the assessment.

[0047] If the oil, gas and water delivery volume does not reach the delivery scale and the actual operating temperature and pressure do not exceed the design value, the designed delivery volume can be considered. If there are conditions on site to increase the maximum delivery capacity of the delivery test pipeline, the maximum delivery volume can be set accordingly. For pipeline expansion assessments that have exceeded their maximum transport capacity, the following assessment methods are used: first, consider the impact of viscosity / components on transport capacity to assess whether the pipeline capacity has been improved; second, consider adding chemical agents, such as drag reducers / viscosity reducers / condensate depressants, etc., to reduce pipeline pressure and water content and improve transport capacity; finally, for pipelines that exceed design values, the subsea pipeline structure needs to be checked for strength and other factors to see if the pipeline capacity can be improved.

[0048] The method for stress analysis of subsea pipeline and riser is: The following data shall be collected: pipeline design data, including design conditions, design pressure, design temperature, design life, commissioning time, etc.; pipeline structure data, including pipe material, structure type, outer diameter, wall thickness, length, etc.; pipeline operation process data, conveying medium data; pipeline cleaning and internal inspection data; external inspection data or comprehensive inspection report, including route survey, external inspection, etc.; pipeline external environmental parameters, such as water depth, waves, current parameters, etc.; overall in-situ strength analysis and riser flexibility analysis for submarine pipelines and risers. For submarine pipelines and risers with corrosion pits, local strength analysis shall be carried out according to the requirements of the specifications, and the analysis results shall meet the requirements of the specifications.

[0049] The method of submarine pipeline corrosion assessment is: collect basic data, including but not limited to the following: basic parameters of submarine pipelines, such as pipe length, structural form, pipe diameter, wall thickness, design corrosion margin, design life, commissioning year, transmission medium, completion design documents, etc. Submarine pipeline corrosion assessment and material selection report, submarine pipeline operation parameters: typical operating conditions inlet and outlet temperatures, inlet and outlet pressures, oil, gas and water transmission volume, outlet liquid phase flow rate. Chemical composition analysis of submarine pipeline inlet and outlet water. Submarine pipeline operation related parameters: CO2 / H2S content and partial pressure at the inlet of the submarine pipeline (the oil and gas mixed transmission submarine pipeline requires bubble point pressure and CO2 / H2S content and partial pressure in the gas phase under bubble point pressure conditions). Microbiological detection data. Corrosion inhibitors, bactericides, deoxidizers and other agents injection status and effect evaluation report. Internal inspection report (including baseline internal inspection). Submarine pipeline potential, sacrificial anode and coating investigation. When the CO2 / H2S partial pressure changes significantly from the design value, the actual production test data is used to calculate the uniform corrosion amount before expansion; when the CO2 / H2S partial pressure does not change significantly from the design value, the data before expansion is based on the original design report; based on the basic data and the results of intelligent internal inspection, the local corrosion rate before expansion is analyzed to evaluate the local corrosion risk of the submarine pipeline; when more than two internal inspection results are obtained, a quantitative calculation of the historical local corrosion rate of typical defect points is carried out; based on the detection and prediction of CO2 / H2S components and partial pressure values ​​in the gas phase, the change in the H2S corrosion cracking risk of in-service submarine pipelines is evaluated; based on the basic data, the current status of external corrosion of submarine pipelines and subsequent operation risks are qualitatively evaluated; based on the above corrosion prediction results and combined with the verification conclusions of the submarine pipeline structure, corrosion prevention and control measures such as process optimization, reagent adjustment, improvement of pipe cleaning strategy, pipeline replacement and monitoring and inspection schemes are proposed.

[0050] The methods for capacity verification of key mechanical equipment include: reciprocating compressor capacity verification method, centrifugal compressor capacity verification method and centrifugal pump capacity verification method.

[0051] The method for checking the capacity of reciprocating compressors is as follows: when expanding the capacity of in-service offshore facilities, the process booster compressors are checked and evaluated, and attention is paid to the actual transmission capacity of the reciprocating compressors; according to feedback from previous project operators, reciprocating compressors often have capacity impairment. For reciprocating compressors with capacity impairment, if the actual transmission capacity cannot meet the needs of capacity expansion and transmission, the reasons for the capacity impairment of the reciprocating compressors should be understood, and the actual processing capacity of the compressors should be determined; for working conditions where the capacity of the reciprocating compressors cannot meet the requirements, compressor modification or replacement, series connection, or parallel connection of new compressors should be considered.

[0052] The method for checking the capacity of centrifugal compressors is as follows: when expanding the capacity of offshore facilities, the process booster compressors should be checked and evaluated, and the actual delivery capacity of the centrifugal compressors should be paid attention to; when checking the centrifugal compressors, the compressor performance curve in the completion document should be used to check the compressor operating points year by year. For operating conditions that cannot be met by the compressor capacity, the compressor core replacement, head replacement, replacement, series connection, parallel connection of new compressors, etc. should be considered for transformation.

[0053] The method for verifying the capacity of centrifugal pumps is as follows: when the capacity of offshore facilities is expanded and increased, the process booster compressor is verified and evaluated, and attention is paid to the actual delivery capacity of the centrifugal pump; when verifying the centrifugal pump, attention is paid to whether the viscosity of the boosting medium has changed, and the pump operating points are verified year by year according to the pump performance curve in the completion document; for operating conditions that cannot be met by the centrifugal pump capacity, replacement, series connection and parallel connection of new pumps should be considered.

[0054] The method for verifying the power supply capacity is as follows: when the capacity of the in-service offshore facilities is expanded and increased, the capacity of the existing main power station of the offshore oil and gas field is verified and evaluated. During the verification, the existing main power station is fully utilized, and the power load demand of the oil field after the expansion and increase of capacity is calculated according to the actual production load of the oil and gas field and the predicted increase in load. The load rate of a single power station should not exceed 90%. When the oil and gas field adopts gas turbine units for power supply, the regional gas balance is verified to ensure that there is enough fuel gas for power supply; the fuel oil / gas consumption required for the expansion of the in-service facilities is calculated, and this part of the impact is considered in the economic evaluation; if the existing power supply capacity of the oil and gas field is insufficient, it is necessary to consider adding a main power station according to the existing conditions of the platform, such as gas production, oil field processing flow, etc., and verify the design capacity of the corresponding public system and auxiliary equipment. The public system includes public instrument air, fresh water, diesel, fuel oil / gas processing capacity, etc.

[0055] The analysis method for platform emergency power stations is as follows: when expanding the capacity and increasing the transmission of offshore facilities in service, attention should be paid to whether the transformation of the facilities will bring about an increase in emergency loads such as emergency replacement, fire protection, and emergency electric heating. If the emergency load changes, the power supply capacity of the emergency machine needs to be verified, and the load rate of the emergency machine should not exceed 90%.

[0056] If the emergency machine capacity is insufficient, the platform emergency load should be optimized as much as possible: investigate the actual emergency load of the platform, sort out the emergency load of the built platform according to the working conditions, and optimize the new load. If it still exceeds the power supply capacity of the emergency machine, the original emergency machine should be replaced with a larger specification.

[0057] The method for design level assessment is: collect relevant technical information, mainly including the following contents: construction completion information, such as construction completion drawings and completion reports; platform transformation information, such as design drawings and reports after transformation; collection of on-site production needs; communication with the site to ensure the consistency between the design drawings and on-site production facilities, etc.

[0058] According to the completed construction drawings and the modified design drawings, find out whether there is any free space and reserved space on the platform; communicate with the mechanical professionals and the site to see if there is any removable equipment; communicate with the structural professionals and the site to see if the deck can be expanded.

[0059] Factors to be considered in platform layout modification include: complying with on-site operating practices as much as possible; focusing on the impact of the modification on the division of dangerous areas, helicopter takeoffs and landings, supply ship berthing, crane use and smoke diffusion; and minimizing the amount of offshore construction and downtime.

[0060] Collect basic assessment data, including but not limited to the following: original design data, such as design basis; design specifications; design drawings; calculation reports, etc. Construction and installation completion data, such as construction completion drawings; construction, welding and inspection specifications; welding process qualification reports (WPS and PQR reports); steel material certificates; installation completion data, etc. Platform use history data, such as environmental load records - typhoons, storms; operational load records - collisions and accidental loads; modification records - drawings, calculation reports; platform inspection and maintenance records, etc.; current condition data, such as the actual size, location, and elevation of all structures; all deck equipment layouts and operational loads; structural inspection and monitoring data; environmental data accumulated in the sea area where the platform is located, etc.

[0061] Basic evaluation data is important information for the platform to conduct evaluation. When basic data is missing or insufficient and affects the normal evaluation, a safe assumption should be made.

[0062] The structural assessment of in-service platforms includes overall structural assessment and local assessment. Local assessment generally requires extracting boundary conditions and loads from the overall assessment for analysis. The overall assessment method is the basis of the structural assessment of in-service platforms.

[0063] The overall assessment method includes the design level analysis method and the ultimate strength analysis method. The overall assessment first conducts the design level analysis assessment. If the assessment passes, the platform structure is safe; if it fails, it should enter the ultimate strength analysis assessment. The design level analysis is similar to the design analysis of a new platform, which includes a certain safety factor and is biased towards safety. The design level analysis includes static analysis, dynamic analysis, fatigue analysis, and seismic analysis. The ultimate strength analysis is used to prove that the platform has sufficient strength and stability to withstand the ultimate strength load without collapsing. The ultimate strength analysis assessment can adopt the local overload analysis method or the overall inelastic overall analysis method (platform collapse analysis method).

[0064] Local assessment methods include local structural dents, corrosion and crack assessments. Dents, corrosion and cracks are common detectable structural damages in in-service platform structures. Analyzing their impact on local structural strength or overall platform strength can provide a scientific basis for operators to formulate reasonable and economical inspection / repair plans. Before conducting local damage assessments, the importance of structural damage structures can be analyzed to provide a reference for assessments or subsequent repair plan decisions.

[0065] The methods of ultimate strength assessment and platform structure anti-corrosion analysis include: data collection basic data collection, including but not limited to the following: platform jacket structure diagram, sacrificial anode structure diagram, layout diagram, cathodic protection specification, material list and other completed design documents. Platform annual inspection, jacket structure protection potential, anode consumption statistics, anode photos, wall thickness monitoring data and other platform structure external corrosion status survey and inspection reports; cathodic protection monitoring system data.

[0066] The platform structure corrosion assessment includes: Focus on assessing the corrosion of the jacket structure. Combine the jacket structure protection potential and sacrificial anode consumption to determine whether the jacket potential is within the protection range specified by the standard. Based on the typical sacrificial anode consumption, qualitatively assess whether the sacrificial anode consumption is reasonable. Based on the corrosion assessment before and after the expansion, propose the risk of supporting after the expansion and transformation. If the risk after the expansion is assessed to be high, propose suggestions for repairing the cathodic protection system.

[0067] For each of the above main devices and systems, the corresponding fuel system, cooling system, instrumentation and control system, power distribution system, public air system, public water system, fire and gas system, fire protection system, piping system, etc., must be comprehensively analyzed and evaluated.

[0068] Based on the reservoir plan and drilling and production plan for increasing oil field production, combined with an objective assessment of the current status of in-service facilities, we formulate a technical plan for capacity expansion and transportation for the engineering profession, and conduct investment estimation and economic evaluation of the overall plan including the reservoir plan, drilling and production plan, and engineering plan.

[0069] Embodiment 2 Based on the same inventive concept, this embodiment discloses a capacity expansion and transportation assessment system for in-service facilities in offshore oil and gas fields, comprising: The basic principle establishment module is used to receive capacity expansion and transportation tasks, and propose the basic principles that the capacity expansion and transportation of in-service production facilities should comply with based on the characteristics of offshore oil and gas fields; The verification and calculation module is used to determine the scope of assessment work, the content of assessment work and the verification and calculation method of each facility for the expansion and improvement of the capacity of offshore facilities based on basic principles, and to generate multiple expansion and improvement plans for different systems; The capacity expansion and transmission optimization module is used to conduct collaborative analysis of different systems. Based on the results of collaborative analysis, multiple capacity expansion and transmission plans are evaluated, fed back and adjusted, unfeasible capacity expansion and transmission plans are eliminated, and a better capacity expansion and transmission plan is generated; The solution review module is used to review the better expansion and transmission solutions, further optimize the expansion and transmission solutions based on the review results, and generate the best expansion and transmission solutions. It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented 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] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0071] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0072] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation of the present invention can still be modified or replaced by equivalents, and any modification or equivalent replacement that does not deviate from the spirit and scope of the present invention should be included in the protection scope of the claims of the present invention. The above content is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for evaluating the expansion of in-service facilities in offshore oil and gas fields, characterized in that: The following steps are involved: Accept the task of capacity expansion and transportation, and propose the basic principles that the capacity expansion and transportation of in-service production facilities should comply with based on the characteristics of offshore oil and gas fields; Based on the basic principles, determine the scope of assessment work for capacity expansion and transmission improvement of offshore facilities in service, the assessment work content and the verification calculation method of each facility, and generate multiple capacity expansion and transmission improvement plans for different systems; Conduct collaborative analysis on different systems, and based on the results of the collaborative analysis, evaluate, provide feedback and adjust the multiple capacity expansion and transmission solutions, eliminate unfeasible capacity expansion and transmission solutions, and generate a better capacity expansion and transmission solution; The preferred capacity expansion and transmission plan is reviewed, and the capacity expansion and transmission plan is further optimized according to the review result to generate the optimal capacity expansion and transmission plan.

2. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 1, characterized in that: The basic principles are based on clear reservoirs and drilling and production plans, the production status of existing production facilities, and in accordance with relevant laws, regulations, standards and specifications. They take into account the coordinated application of existing technologies and facilities with new technologies and new facilities, as well as the comprehensive generation of technical, economic, safety, environmental protection and energy-saving factors.

3. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 1, characterized in that: The scope of the assessment work includes: assessment of crude oil processing system, natural gas processing system, produced water treatment system, subsea pipeline transmission system, power supply and distribution system, platform space, platform structure and public support system; the capacity expansion and transmission plan includes technical solution analysis and economic analysis. The technical solution analysis includes the expansion and transformation plan of the original equipment and the analysis of the new process or equipment plan; the economic analysis includes investment estimate and economic evaluation.

4. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 3, characterized in that: The assessment work content and the verification calculation method of each facility are as follows: verification of oil, gas and water treatment capacity, verification of submarine pipeline transportation capacity, verification of key mechanical equipment capacity, verification of power supply capacity, verification of platform structure and verification of public support system; The oil, gas and water treatment capacity verification includes: oil and gas treatment facility capacity assessment; water treatment facility capacity assessment and analysis of new oil, gas and water treatment facility plans; The submarine pipeline transportation capacity verification includes: submarine pipeline process capacity assessment, sea pipe and riser stress analysis, corrosion pit pipeline status evaluation and residual strength analysis and submarine pipeline corrosion assessment; The key mechanical equipment capacity verification includes: reciprocating compressor capacity verification, centrifugal compressor capacity verification and centrifugal pump capacity verification; The power supply capacity verification includes: platform main power station analysis, regional power grid analysis and platform emergency power station analysis; The platform structure verification includes: design level assessment, ultimate strength assessment and platform structure anti-corrosion analysis; The verification of utility support systems includes: fuel system, cooling system, instrumentation and control system, power distribution system, utility system, fire and gas system, fire protection system and piping system capability assessment.

5. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 4, characterized in that: The oil and gas processing facility capacity assessment method and the water treatment facility capacity assessment method include: Collect original design data, construction completion data, platform modification data and current equipment and facility data; By obtaining the above information and data, we can understand the in-service oil and gas or water treatment process and compare it with the data after the expansion and transportation is completed to confirm whether there are differences with the designed equipment and process, and the reasons for the differences; Obtaining the operating parameters of the oil and gas treatment process or the water treatment process during actual operation, and determining whether the operating parameters meet the design conditions and the design treatment effects; If the treatment flow rate does not reach the design value but the actual treatment effect is good, the equipment and treatment system are considered to be in good condition; if the treatment flow rate reaches the design value and the actual treatment effect is good, the treatment process is considered to be suitable for the current design parameters; if the treatment flow rate does not reach the design value and the actual treatment effect fluctuates during operation, but the overall treatment effect can still meet the design requirements, consider coordinating on-site to adjust the chemical injection point and concentration, test whether the treatment effect of the oil, gas or water treatment system is improved, and combine the on-site operation conditions to find out the restrictive factors and carry out targeted modifications or add corresponding equipment.

6. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 5, characterized in that: The method for analyzing the scheme of adding oil, gas and water treatment facilities is as follows: After technical and economic analysis, the treatment process with reasonable design and good treatment effect in the in-service treatment system will be directly used; If a more suitable treatment process that meets access requirements is found after technical and economic analysis, the new facility should adopt the new process in parallel with the original process; For existing production processes with unstable treatment effects, analyze the reasons leading to poor treatment effects, avoid this problem in new treatment processes, and calibrate the treatment scale of existing treatment systems according to their maximum treatment capacity that can ensure treatment effects.

7. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 4, characterized in that: The method for evaluating the corrosion of submarine pipelines is: Collect basic data. When the CO2 / H2S partial pressure changes significantly from the design value, use the actual production test data to calculate the uniform corrosion amount before expansion. When the CO2 / H2S partial pressure does not change significantly from the design value, the data before expansion is based on the original design report. According to the basic data, based on the intelligent internal inspection results, analyze the local corrosion rate before expansion and evaluate the local corrosion risk of submarine pipelines; when more than two internal inspection results are obtained, carry out quantitative calculation of the historical local corrosion rate of typical defect points; Based on the detection and prediction of CO2 / H2S components and partial pressure values ​​in the gas phase, the risk of H2S corrosion cracking in in-service submarine pipelines is assessed; Based on basic data, qualitatively evaluate the current status of submarine pipeline external corrosion and subsequent operation risks; Based on the above corrosion prediction results and combined with the verification conclusions of the offshore pipeline structure, corrosion prevention and control measures such as process optimization, reagent adjustment, pigging strategy improvement, pipeline replacement and monitoring and detection scheme are proposed.

8. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 4, characterized in that: The method for checking the capability of key mechanical equipment includes: When expanding the capacity and increasing the transmission of offshore facilities, the process booster compressors and pumps shall be calibrated and evaluated, and attention shall be paid to the actual transmission capacity of reciprocating compressors, centrifugal compressors and centrifugal pumps; for reciprocating compressors with capacity impairment, if the actual transmission capacity cannot meet the expansion and transmission needs, the reasons for the capacity impairment of the reciprocating compressors shall be understood, and the actual processing capacity of the compressor shall be determined; for working conditions where the capacity of the reciprocating compressors cannot meet the requirements, compressor modification or replacement, series connection or parallel connection of new compressors shall be considered; for centrifugal compressors, the compressor operating points shall be calibrated year by year according to the compressor performance curve in the completion document, and for working conditions where the capacity of the centrifugal compressors cannot meet the requirements, compressor core replacement, head replacement, replacement, series connection or parallel connection of new compressors shall be considered; for centrifugal pumps, attention shall be paid to whether the viscosity of the boosting medium has changed, and the pump operating points shall be calibrated year by year according to the pump performance curve in the completion document; for working conditions where the capacity of the centrifugal pumps cannot meet the requirements, replacement, series connection or parallel connection of new pumps shall be considered.

9. The method for evaluating the expansion of in-service facilities in offshore oil and gas fields according to claim 4, characterized in that: The method for checking the power supply capability comprises: When the capacity of in-service offshore facilities is expanded and the transmission is increased, the capacity of the existing main power station of the offshore oil and gas field is verified and evaluated. During the verification, the electrical load demand of the oil field after the expansion and transmission is calculated based on the actual production load of the oil and gas field and the predicted increase in load; when the oil and gas field adopts gas turbine units for power supply, the regional gas balance is verified to ensure that there is sufficient fuel gas for power supply; the fuel oil / gas consumption required for the expansion and transmission of in-service facilities is calculated, and this part of the impact is taken into account in the economic evaluation; if the existing power supply capacity of the oil and gas field is insufficient, it is necessary to consider adding a main power station based on the existing conditions of the platform, and at the same time verify the corresponding public systems.

10. An offshore oil and gas field in-service facility expansion and transportation assessment system, characterized in that: include: The basic principle establishment module is used to receive capacity expansion and transportation tasks, and propose the basic principles that the capacity expansion and transportation of in-service production facilities should comply with based on the characteristics of offshore oil and gas fields; A verification and calculation module is used to determine the scope of assessment work for the expansion and improvement of the capacity of offshore facilities in service, the content of assessment work and the verification and calculation method of each facility according to the basic principles, and generate multiple expansion and improvement plans for different systems; The capacity expansion and transmission optimization module is used to perform collaborative analysis on different systems, and based on the results of the collaborative analysis, evaluate, feedback and adjust multiple capacity expansion and transmission plans, eliminate unfeasible capacity expansion and transmission plans, and generate a better capacity expansion and transmission plan; The scheme review module is used to review the better capacity expansion and transmission scheme, further optimize the capacity expansion and transmission scheme according to the review result, and generate the best capacity expansion and transmission scheme.

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