System Analysis and Application of Combined System of ESP and Gas Lift

Abstract With the development of deep-buried reservoirs and offshore fields, many prominent problems have been encountered by the use of conventional single artificial lift technologies, which can not meet the requirements of production and may cause frequent workovers. The combination of electrical submersible pump (ESP) and gas lift system (GL), taking advantages of flexible pump rate, relative long workover intervals and simple composition of tubing strings, is considered to be a better solution. The design of ESP-GL combined system is more complicated, referring to the distribution of pressure, temperature and viscosity fields of multiphase flow in the tubing string. In this article, based on the performance curves of lift devices and oil well, the design approach of the ESP-GL combined system based on nodal analysis is established with an example calculation. An optimization design approach of the combined system is then developed by intelligent algorithms, considering some key operating parameters, e.g. pump drainage rate, ESP depth, ESP stages, valve depth and gas injection rate, to find the optimal operating condition of the system. At the same time, the combined lifting system has been successfully applied in some pilot tests in China and Vietnam reporting to have production increments, which suggests a good potential for the application of the ESP-GL combined system in deep fields.

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Gas lift optimization in the oil and gas production process: a review of production challenges and optimization strategies

International Journal of Industrial Optimization ◽

10.12928/ijio.v1i2.2470 ◽

2020 ◽

Vol 1 (2) ◽

pp. 61

Author(s):

Ikenna Tobechukwu Okorocha ◽

Chuka Emmanuel Chinwuko ◽

Chika Edith Mgbemena ◽

Chinedum Ogonna Mgbemena

Keyword(s):

Production Process ◽

Oil And Gas ◽

Gas Injection ◽

Injection Rate ◽

Gas Production ◽

Optimization Techniques ◽

Oil Well ◽

Oil And Gas Production ◽

Artificial Lift ◽

Gas Lift

Gas Lift operation involves the injection of compressed gas into a low producing or non-performing well to maximize oil production. The oil produced from a gas lift well is a function of the gas injection rate. The optimal gas injection rate is achieved by optimization. However, the gas lift, which is an artificial lift process, has some drawbacks such as the deterioration of the oil well, incorrect production metering, instability of the gas compressor, and over injection of gas. This paper discusses the various optimization techniques for the gas lift in the Oil and Gas production process. A systematic literature search was conducted on four databases, namely Google Scholar, Scopus, IEE Explore and DOAJ, to identify papers that focused on Gas lift optimizations. The materials for this review were collected primarily via database searches. The major challenges associated with gas lift were identified, and the different optimization strategies available in the literature reviewed. The strategies reviewed were found to be based on artificial intelligence (AI) and machine learning (ML). The implementation of any of the optimization strategies for the gas lift will enhance profitability, reduce operational cost, and extend the life of the wells.

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Numerical Simulation of Gas Lift Optimization Using Artificial Intelligence for a Middle Eastern Oil Field

10.2118/207341-ms ◽

2021 ◽

Author(s):

Mohammed Ahmed Al-Janabi ◽

Omar F. Al-Fatlawi ◽

Dhifaf J. Sadiq ◽

Haider Abdulmuhsin Mahmood ◽

Mustafa Alaulddin Al-Juboori

Keyword(s):

Genetic Algorithm ◽

Sensitivity Analysis ◽

Middle Eastern ◽

Optimization Technique ◽

Injection Rate ◽

Oil Field ◽

Oil Fields ◽

Reservoir Pressure ◽

Artificial Lift ◽

Gas Lift

Abstract Artificial lift techniques are a highly effective solution to aid the deterioration of the production especially for mature oil fields, gas lift is one of the oldest and most applied artificial lift methods especially for large oil fields, the gas that is required for injection is quite scarce and expensive resource, optimally allocating the injection rate in each well is a high importance task and not easily applicable. Conventional methods faced some major problems in solving this problem in a network with large number of wells, multi-constrains, multi-objectives, and limited amount of gas. This paper focuses on utilizing the Genetic Algorithm (GA) as a gas lift optimization algorithm to tackle the challenging task of optimally allocating the gas lift injection rate through numerical modeling and simulation studies to maximize the oil production of a Middle Eastern oil field with 20 production wells with limited amount of gas to be injected. The key objective of this study is to assess the performance of the wells of the field after applying gas lift as an artificial lift method and applying the genetic algorithm as an optimization algorithm while comparing the results of the network to the case of artificially lifted wells by utilizing ESP pumps to the network and to have a more accurate view on the practicability of applying the gas lift optimization technique. The comparison is based on different measures and sensitivity studies, reservoir pressure, and water cut sensitivity analysis are applied to allow the assessment of the performance of the wells in the network throughout the life of the field. To have a full and insight view an economic study and comparison was applied in this study to estimate the benefits of applying the gas lift method and the GA optimization technique while comparing the results to the case of the ESP pumps and the case of naturally flowing wells. The gas lift technique proved to have the ability to enhance the production of the oil field and the optimization process showed quite an enhancement in the task of maximizing the oil production rate while using the same amount of gas to be injected in the each well, the sensitivity analysis showed that the gas lift method is comparable to the other artificial lift method and it have an upper hand in handling the reservoir pressure reduction, and economically CAPEX of the gas lift were calculated to be able to assess the time to reach a profitable income by comparing the results of OPEX of gas lift the technique showed a profitable income higher than the cases of naturally flowing wells and the ESP pumps lifted wells. Additionally, the paper illustrated the genetic algorithm (GA) optimization model in a way that allowed it to be followed as a guide for the task of optimizing the gas injection rate for a network with a large number of wells and limited amount of gas to be injected.

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Global Optimization of Gas Allocation to a Group of Wells in Artificial Lift Using MATLAB

Part A: Combustion and Alternative Energy Technology; Computers in Engineering; Drilling Technology; Environmental Engineering Technology; Composite Materials Design and Analysis; Manufacturing and Services ◽

10.1115/etce2001-17135 ◽

2001 ◽

Author(s):

Gabriel A. Alarcón ◽

Carlos F. Torres-Monzón ◽

Nellyana Gonzalo ◽

Luis E. Gómez

Keyword(s):

Production Rate ◽

Optimization Technique ◽

Gas Injection ◽

Nonlinear Function ◽

Oil Production ◽

Oil Well ◽

Artificial Lift ◽

Total Oil ◽

Gas Lift ◽

Injection Rates

Abstract Continuous flow gas lift is one of the most common artificial lift method in the oil industry and is widely used in the world. A continuous volume of gas is injected at high pressure into the bottom of the tubing, to gasify the oil column and thus facilitate the extraction. If there is no restriction in the amount of injection gas available, sufficient gas can be injected into each oil well to reach maximum production. However, the injection gas available is generally insufficient. An inefficient gas allocation in a field with limited gas supply also reduces the revenues, since excessive gas injection is expensive due to the high gas prices and compressing costs. Therefore, it is necessary to assign the injection gas into each well in optimal form to obtain the field maximum oil production rate. The gas allocation optimization can be considered as a maximization of a nonlinear function, which models the total oil production rate for a group of wells. The variables or unknowns for this function are the gas injection rates for each well, which are subject to physical restrictions. In this work a MATLAB™ nonlinear optimization technique with constraints was implemented to find the optimal gas injection rates. A new mathematical fit to the “Gas-Lift Performance Curve” is presented and the numeric results of the optimization are given and compared with results of other methods published in the specialized literature. The optimization technique proved fast convergence and broad application.

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Now Is the Time for Gas Lift To Live Up to Its Potential

Journal of Petroleum Technology ◽

10.2118/0521-0021-jpt ◽

2021 ◽

Vol 73 (05) ◽

pp. 21-27

Author(s):

Stephen Rassenfoss

Keyword(s):

Gas Injection ◽

Oil Well ◽

Variable Speed Drives ◽

Well Production ◽

Artificial Lift ◽

New Thinking ◽

Base Management ◽

Pumping Units ◽

The Cost ◽

Gas Lift

Gas lift is one of the most popular ways to increase oil-well production, and it is no secret that it is an underperformer. Back in 2014, ExxonMobil reported that by creating a team of roving gas-lift experts it was able to add an average of 22% more output on several hundred wells where the gas injection had been optimized. Gains were expected because “wells do not remain the same over time; they change,” said Rodney Bane, global artificial-lift manager at ExxonMobil, in this JPT story covering the 2014 SPE Artificial Lift Conference and Exhibition (https://jpt.spe.org/paying-close-attention-gas-lift-system-can-be-rewarding). The problem with gas injection is that change is hard. Injection adjustment or repairs require either pulling the tubing to reach the injection mandrels or a wireline run. Those with good- producing wells, particularly offshore, need to weigh the possible gain against the cost and lost production during the job. Those managing more and more wells live with iffy data, injection systems prone to malfunction, horizontal wells prone to irregular flows, and a time-consuming process for calculating the proper injection rates. New approaches addressing those negatives have led a few big operators to try new systems designed to allow constant adjustments based on downhole data with electric control systems designed to be more reliable. Programmable digital controls raise an obvious question: How do you take advantage of that capability? Constantly updated injection data based on traditional evaluation methods is the first step. And new capabilities are inspiring new thinking about how injected gas lifts production and how to make it work more efficiently. Optimizing the process has not been a priority in gas lift. “It was a fairly imprecise thing. But the beauty of gas lift is it works even where it’s broken. It’s not a pump; it’s flow assurance,” said Brent Vangolen, surface and base management technology manager with Occidental. Occidental is among the early adopters of new gas-lift methods along with companies including Chevron, Shell, ExxonMobil, Petronas, and ADNOC. Vangolen expects the industry will follow. “Gas lift is going through the same transformation as rod pumps went through in the 60s and 70s,” he said. Back then, rod pump engineers began tracking changes in the load on the rod through each pump stroke by using dynamometer cards. That data was used to better program pump controls. “You went from egg timers on pumping units to full-blown optimization pumpoff controllers, variable speed drives … this huge infant technology that changed the rod pump space,” he said. Papers at last year’s SPE artificial lift conference covered the continuing digitization in rod lift and that gas lift was finally moving in that direction.

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Global Optimization of Gas Allocation to a Group of Wells in Artificial Lift Using Nonlinear Constrained Programming

Journal of Energy Resources Technology ◽

10.1115/1.1488172 ◽

2002 ◽

Vol 124 (4) ◽

pp. 262-268 ◽

Cited By ~ 61

Author(s):

Gabriel A. Alarco´n ◽

Carlos F. Torres ◽

Luis E. Go´mez

Keyword(s):

Production Rate ◽

Optimization Technique ◽

Gas Injection ◽

Nonlinear Function ◽

Oil Production ◽

Oil Well ◽

Artificial Lift ◽

Total Oil ◽

Gas Lift ◽

Injection Rates

Continuous flow gas lift is one of the most common artificial lift methods widely used in the oil industry. A continuous volume of high-pressure gas is injected as deep as possible into the tubing, to gasify the oil column, and thus facilitate the production. If there is no restriction in the amount of injection gas available, sufficient gas can be injected into each oil well to reach maximum production. However, the injection gas available is generally insufficient. An inefficient gas allocation in a field with limited gas supply reduces the revenues, since excessive gas injection is expensive due to the high gas prices and compressing costs. Therefore, it is necessary to assign the injection gas into each well in optimal form to obtain the field maximum oil production rate. The gas allocation optimization can be considered as a maximization of a nonlinear function, which models the total oil production rate for a group of wells. The variables or unknowns for this function are the gas injection rates for each well, which are subject to physical restrictions. In this work a nonlinear optimization technique, based on an objective function with constraints, was implemented to find the optimal gas injection rates. A new mathematical fit to the gas-lift performance curve (GLPC) is presented and the numeric results of the optimization are given and compared with those of other methods published in the specialized literature. The GLPC can be either measured in the field, or alternatively generated by computer simulations, by mean of nodal analysis. The optimization technique proved fast convergence and broad application.

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GAS LIFT OPTIMIZATION OF A MATURE WELL IN NIGER DELTA, NIGERIA USING INCOMPLETE DATASET: A CASE STUDY

Engineering Heritage Journal ◽

10.26480/gwk.01.2020.15.18 ◽

2020 ◽

Vol 4 (1) ◽

pp. 15-18

Author(s):

Oghenegare E. Eyankware ◽

Idaereesoari Harriet Ateke ◽

Okonta Nnamdi Joseph

Keyword(s):

Niger Delta ◽

Gas Injection ◽

Injection Rate ◽

Wellhead Pressure ◽

Well Production ◽

Artificial Lift ◽

Lift Mechanism ◽

Fluid Production ◽

Water Cut ◽

Gas Lift

Well DEF, a well located in Niger Delta region of Nigeria was shut down for 7 years. On gearing towards re-starting production, different options such as installation of gas lift mechanism, servicing and installation of packers and valves were evaluated for possibility of increasing well fluid productivity. Hence, this research was focused on optimizing well fluid productivity using PROSPER through installation of continuous gas lift mechanism on an existing well using incomplete dataset; in addition, the work evaluated effect of gas injection rates, wellhead pressure, water cut and gas gravity on efficiency of the artificial lift mechanism for improved well fluid production. Results of the study showed that optimum gas injection rate of 0.6122 MMscf/day produced well fluid production of 264.28 STB/day which is lower than pristine production rate (266 STB/day) of the well. Also, increment in wellhead pressure resulted in decrease in well production, increase in water cut facilitated reduction in well fluid productivity while gas gravity is inversely proportional to well fluid productivity. Based on results obtained, authors concluded that Well DEF does not require gaslift mechanism hence, valves and parkers need to be re-serviced and re-installed for sustained well fluid.

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Digital Intelligent Artificial Lift DIAL Gas Lift Production Optimization Deployments Across Assets

10.2118/206182-ms ◽

2021 ◽

Author(s):

Ahmed Alshmakhy ◽

Yann Bigno ◽

Talha Saqib ◽

Moazim Soomro ◽

Juan Faustinelli ◽

...

Keyword(s):

Injection Rate ◽

American Petroleum Institute ◽

Production Optimization ◽

Flow Area ◽

Well Production ◽

Surface Control ◽

Artificial Lift ◽

Technical Details ◽

Gas Lift

Abstract Abu Dhabi National Oil Company (ADNOC) is expanding the use of DIAL (Digital Intelligent Artificial Lift) technology, across its assets, through a range of different oil production applications. These include gas lifted single and dual completions, Extended Reach Drilling (ERD) wells and In-Situ gas lift. DIAL is a first-of-kind technology that enhances the efficiency of gas lift through downhole data, surface control and digital operations. This data driven approach enables production automation and minimizes well intervention requirements. This paper will present four different applications for the technology. These applications were selected by ADNOC assets, as they were deemed to bring the most value for DIAL implementation. The paper will describe technical details for each application, including gas lift designs, completion specificities, installation procedures and benefits observed or anticipated. A summary of the value add for each of the four applications are listed below. Gas lifted single completion is the most common application for the DIAL system. The benefits of the application have been described in previous papers and range from intervention savings to production optimization. This paper will highlight the additional benefit of automation, making full use of the system digital features. Gas lifted dual string completion, where the technology enables efficient lift of both strings, improving well production in the range of 40 to 100%. API (American Petroleum Institute) does not recommend pressure operated gas lift in dual wells. DIAL offers stability, simultaneous lifting of both strings through surface control and downhole data. ERD gas lifted well required flexibility for its gas lift operations. DIAL enables real time changes of injection depths based on reservoir response, and units can be installed deeper into the deviated section of the well without any deviation limits. In-Situ gas lift is a specific application where a gas zone is used to lift production from the oil zone in the same well. DIAL enables measurement of the gas injection rate at the point of injection, and adjustment of the flow area to optimize production. This is a world's first use of the technology for this type of application. A range of applications are described in this paper with many technical details, recommendations and lessons learnt to enable replication within the industry. Some of these applications are world first.

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Design and Economic Evaluation of the ESP and Gas Lift on the Dead Oil Well

International Journal of Current Engineering and Technology ◽

10.14741/ijcet/v.8.6.5 ◽

2018 ◽

Vol 8 (6) ◽

Author(s):

Imran A. Hullio ◽

Sarfraz A. Jokhio ◽

Khalil Rehman Memon ◽

Sohail Nawab ◽

Khair Jan Baloch

Keyword(s):

Capital Budgeting ◽

Production Performance ◽

Oil Well ◽

Production Rates ◽

Production Forecast ◽

Artificial Lift ◽

Operating Expenditures ◽

Water Cut ◽

Gas Lift ◽

Design And Production

Owing to the increasing water cut and decreasing in reservoir pressure of the well, the oil production of the well has seized and the well has become dead. This research study evaluates the implementation of the artificial lift methods ESP and Gas Lift- economically and technically on the well by using the production performance software (PROSPER) and economical yardsticks (NPV and ROI). The theory, design, production forecast, capital and operating expenditures of the electric submersible pump and gas lift are discussed for the appropriate selection of any of two options. The PROSPER software is used as the simulation tool for the design and production forecasting of the ESP and Gas Lift based. The ESP and Gas Lift methods have been simulated for the design and production forecast by entering the reservoir and completion inputs in the software. Subsequently, the software has been simulated to run on different sensitivities of the variables such as water cut, wellhead pressure setting depth, operating frequency and gas injection rates to check the production rates at different scenarios. Having performed the production performance simulation on the selected artificial lift methods, the methods have been investigated by capital budget-ing. In capital budgeting, the capital and operating expenditures of both lift methods were evaluated by determining their discounted value (NPV) and re-turn on investment (ROI). The prime objective of the research is to accomplish maximum production rates and profitability by selecting the most appropriate artificial lift method for the well; as a consequence it is concluded that the suitable artificial lift method for a well can be selected by applying the simulation and economical schemes.

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