Gas Condensate Wells Research Articles

Метод определения содержания воды в продуктах добычи газоконденсатных и нефтегазоконденсатных скважин с помощью СВЧ-анализатора, работающего при отрицательных температурах

Метод определения содержания воды в продуктах добычи газоконденсатных и нефтегазоконденсатных скважин с помощью СВЧ-анализатора, работающего при отрицательных температурах

Modeling of the lifting of a heat transfer agent in a geothermal well of a gas condensate deposit

The authors are grateful to Ukrgazvydobuvannya PJSC for the opportunity to obtain both empiric materials and parametric data concerning gas condensate wells of Lanivske GCD.

Организация высокоточных измерений объемных долей газа, воды и конденсата в продуктах добычи газоконденсатных и нефтегазоконденсатных скважин

Организация высокоточных измерений объемных долей газа, воды и конденсата в продуктах добычи газоконденсатных и нефтегазоконденсатных скважин

A productivity prediction method for condensate gas reservoir

At present, multiphase flow productivity calculation requires many parameters, and most of them only consider oil and gas two-phase flow, which is complicated and limited. Therefore, a reasonable productivity formula of condensate gas reservoir with producing water is needed. The three-zone model of condensate gas reservoirs is generally applied to the physical model for inferring productivity. On this basis, an improved model is established, which includes that different seepage characteristics are considered for different zones. Moreover, the effects of inclined angle and water production on gas wells are regarded as pseudo-skin factors and additional-skin factors. In addition, Zone I considers the effects of high-speed nonDarcy effect(HSND), starting pressure gradient, stress sensitivity, inclined angle and water production; Zone II is the same way excepting starting pressure gradient and stress sensitivity ; Zone III only considers the effects of inclined angle and water production. As a result, a productivity equation with multiple factors for condensate gas wells is established. Through analysing cases and influences in H gas reservoir X1 well, the HSND, starting pressure gradient, stress sensitivity and water production have a negative impact on gas well productivity, but the inclined angle is opposite. Founded that the starting pressure gradient impacts on productivity is less than the HSND because of the limited radius of Zone I; the impact of the HSND on productivity increases with the decreasing of bottom hole pressure; the impact of water production on gas well productivity is much higher. When the angle is over 60°, the effect of gas

A new approach for predicting critical gas rate in condensate gas wells

A new approach for predicting critical gas rate in condensate gas wells

К решению проблемы регистрации примесей в многофазном потоке продукции газовых и газоконденсатных скважин

К решению проблемы регистрации примесей в многофазном потоке продукции газовых и газоконденсатных скважин

Использование моды H111 в СВЧ-плотномерах продуктов добычи газоконденсатных и нефтегазоконденсатных скважин при дисперсно-кольцевом режиме газожидкостного потока

Использование моды H111 в СВЧ-плотномерах продуктов добычи газоконденсатных и нефтегазоконденсатных скважин при дисперсно-кольцевом режиме газожидкостного потока

Pilot testing of development wells technology to restore performance

Issues in focus. The paper deals with a topical issues related to the development of depleted reservoir wells. To develop wells with low reservoir pressures, different technologies are used that involve the use of new equipment.Objective. Experimentally investigate the technology of wells exploration at the final stages of development. To obtain reservoir fluid at low reservoir pressures, it is important to choose the optimal well development technology.Methods of implementation. Specialists of the Ukrainian Scientific Research Institute of Natural Gases have developed a device for foam production and well development. By applying it, foam can be obtained to remove the fluid from the bottom and the well shaft, which will restore the wells performance. The design and operation principle of this device have been developed. Experimental and industrial tests of exploration of gas-condensate wells technology using foam were carried out.Research results. As a result of the exploration work, fluid was removed from the wells by injection of non-explosive gas mixture and foam. During the work, the pipe and annulus pressures were monitored as well as the output of the well at the flare barn. After injection of the foam formed from the solution of surfactants, the pumping unit was stopped, while the non-explosion gas mixture was continued to be pumped by mobile nitrogen compressor stations. The foam was injected at intervals, defined by individual plan of work. At the end of the of foam (liquid) flow on the flare barn, the development work was stopped. The pipe and annulus pressures and also their growth were monitored. The well was commissioned and the parameters of its operation were monitored. Based on the measured production capacity of the wells, an increase in gas flow was obtained.Conclusions. Thanks to the presented technology of wells development it is possible to achieve a positive result on the depleted gas condensate fields. The industrial application of the development technology in practice will allow to achieve the expected wells flow rate and to provide stable production of hydrocarbons.

СУЧАСНИЙ НАПРЯМОК ОПТИМІЗАЦІЇ ПРОЦЕСУ ДОСЛІДЖЕНЬ ГАЗОВИХ ТА ГАЗОКОНДЕНСАТНИХ СВЕРДЛОВИН

The purpose of wells research, as known, finding as possible of greater information content is about a productive layer and saturant him layer flyuid. Because these information is basis for productive descriptions of object determination and him potential extractive possibilities. For this reason exactness of determination of gas-hydrodynamic parameters is the mortgage of exactness of supplies count of products in a productive well. That, from one side the amount of the parameters of layers expected due to gas-hydrodynamic researches plays an important role. De autre part quality of these parameters is a no less valuable index for their next use. Coming from the analysis of the state of works from researches of gas and gas-condensate wells from point of complication, costs, duration, ecological aspect, it is discovered that it is possible positive to count implementation of works from wells research in the case of stationary filtration on traditional technology or on new technology - on one actually exhaust mode. In first case get parameters in a two-bit. Some of them determine laboratory or geophysical methods, as for example, coefficient of porosity or effective power of productive layer. In second case of parameters it is possible to get in once or twice anymore. Thus all of them settle accounts analytically. And exactly it talks in behalf of their exactness. In the case of research of high-permeability layers which are characterized non-stationary filtration, research is based on the receipt of curves of proceeding in pressure application of mathematical receptions for a receipt by findings interpretation of necessary information about the probed layers. Therefore the developed method of research and method of interpretation of got is actual here information. In a publication some important elements of calculation method of gas-hydrodynamic parameters of productive gas and gas-condensate wells are also resulted for the case of non-stationary products filtration to the well bottom. On the whole increase of amount of the expected gas-hydrodynamic parameters of the system hole-layer at wells research only on one actually exhaust mode and increase of their quality due to the removal of laboratory and geophysical methods is the elements of process optimization of wells research. Plays the not last role circumstance that information turns out due to interpretation self-containment of fact sheets only of one research mode. Other from 5-8 traditional modes become unnecessary in practical realization. And if a well works not in a gas pipeline, it is possible to present as far as it is a keeping factor for an ecological environment. And in the scales of all planet it no doubt will promote stabilizing of climatic terms, which presently are not in the best state. Key words: research of wells, non-stationary filtration mode, gas-hydrodynamic parameters References Akulshin O.O., N.N. Roy. 2008. The use of calculation and analytical methods is during gas and gas-condensate wells research. Oil and gas industry. №4. P. 40-41. (in Ukrainian). Akulshin O.O., Roy N.N. Increase of efficiency of gas and gas-condensate wells research. Problems of oil and gas industry. №9. P. 227-234. (in Ukrainian). Akulshin O.O., N.N. Roy. Monitoring of industrial information is at research of gas and gas-condensate wells at the non-stationary filtration mode: thesis of scientific-practical conference «Oil and Gas energy 2013». Ivano-Frankivsk. P. 507 - 512 (in Ukrainian). Sotov G.A. Tverkovkin C.M. 1970. Gas-hydrodynamic methods of gassers research. Nedra. 192 p. (in Russian). Instruction on research of gassers M. Gostoptechisdat. 110 p. (in Russian). Instruction on complex and gas-condensate wells research. 1971. Nedra. 208 p. (in Russian). Zotova G.A., Alieva Z.C. et al. 1980. Instruction on complex research of and gas-condensate layers and wells. M.Nedra. 301 p. (in Russian). Matus B.A., Roy N.N., Lastovka Y.V. and al. 2005. About possibility of wells research on one stationary mode. Collection of scientific works UkrS №2. P. 210-211. (in Ukrainian). Matus B.A., Kuriluk L.B., Slavin B.I., Gorlacheva L.F., Tokarev V.P., Klimenko U.O.; decl and hold. Matus B.A. 16.12.02. 51729 Ukraine, MPK Е21В 47/06. Method of gassers research. № U 200601237; decl. 01.04.99. publ. Buil. №12. (in Ukrainian). Roy N.N. decl and hold. Roy N.N. 02.17. Pat. 121860 Ukraine, MPK (2017.01) Е21 В 47/00 A method of highly productive gas and gas-condensate wells research is at the non-stationary filtration mode. decl. publ. 26.12.17. Biul. №24 (in Ukrainian). Gritsenko A.I., Aliev Z.C., Ermilov O.M. et al. 1995. Guidance on wells research. M. Nauka. 523 p. (in Russian). Tcekalyuk E.B. 1961. Bases piezometry of oil and gas beds K. State publishing house of technical literature USSR. 286 p. (in Russian).

ДО ПИТАННЯ ПРО ГІДРОДИНАМІЧНИЙ ОПІР ПРИ РУСІ БРИКЕТУ У СЕРЕДОВИЩІ РІДИНИ ТА ГАЗУ

The problem of stabilizing and increasing the production of hydrocarbons is a topical issue today for most of the countries involved in oil and gas production. In order to reduce energy consumption in work on increasing productivity of oil and gas wells, the issues of intensification of hydrocarbon production due to the use of compact technologies, which involve increasing the productivity of the wells due to the supply of active chemreagents in the form of briquettes or capsules, are considered. As fillers, depending on the chosen type of well treatment technology, powder acids, surfactants, corrosion inhibitors, hydrate formation, salt deposition can be used. In the pump-compressor pipes, briquettes or capsules are fed to the outlet of the well, where the reagents they contain are activated and their or those physico-chemical technological processes of the intensification of the operation of the well-reservoir system are carried outThe effectiveness of the technological processes of compact technology depends not only on the presence and activity of chemical reagents on the well hole, but also on the sequence of introduction of briquettes or capsules into the well, and, to a large extent, from the time of their movement to the face.The motion of briquettes or capsules in the wellbore is explored, the formula for calculating the time of briquettes movement and the optimal geometric form of briquettes are determined. For technological operations using compact technology, it is recommended to use briquettes or capsules in the form of a cone with an angle at the apex of its axial section α = 30 °. As an example, the practical experience of introducing compact technology for the stabilization and increase of natural gas extraction in the deposits of Ukraine and the Republic of Poland through the removal of liquid from the faces of gas and gas condensate wells is provided by the use of conic shaped briquettes containing the surfactant. Key words: performance of wells, compact technology, surfactant, powdery acids inactive, corrosion inhibitors and saline deposition References AS USSR #1760095. 1992. Foam for removal of liquid from the bottom of the well. Svetlitsky VM, Balakirov Yu.A., Yagodovsky SI, Abramov Yu.D., Bantush V. Bull. # 33. (In Russian). AS USSR #1623293. Svetlitsky V.М., Balakirov Yu.A., Yagodovsky S.I., Ryabov Yu.G. The method of development of oil and gas wells. Not published (restricted). EgerO., Rybchych I.Y. 2003. Influence of the state of the filtration characteristics of the hinterland zone of multilayer layers on the efficiency of the development of oil and gas fields. Lviv. Liga-Press. 116 p. (In Ukrainian). Idelchik I.E. 2012. Handbook for hydraulic resistance. M. Book on Demand. 466 p. (In Russian). Kachmar Yu.D., Svetlitsky V.М. 2004. Intensity of the inflow of hydrocarbons in the well. Lviv: Center of Europe. 352 p. (In Ukrainian). Patent of Ukraine for Utility Model No 2017. Zelensky V.Yu., Krivulya S.V., Zelensky M.V., Yaschenko O., Yagodovsky S.I. Method of treatment of wells by the method of supplying chemical components on bottom. 25.04.2017 Bull. # 8. (In Ukrainian). Rabinovich E.Z. 1980. Hydraulics. M. Nedra. 278 p. (In Russian). Svetlitsky V.M., Yagodovsky S.I., Galustyan G.R. 2001. Current and overhaul of wells. K. Logos. 344 p. (In Ukrainian). Svetlitsky V.M., Yagodovsky S.I. 1998. Stimulating the operation of wellbore at the Junyuan oil and gas production fields. Kyiv. Logos. 43 p. (In Russian). Yagodovsky S.I., Balakirov Yu.A., Svetlitsky V.М. 1989. Removal of liquid from the bottoms of gas and gas condensate wells. In the book: Thermo-gas-dynamic processes and their control systems in exploration, transportation and production of oil and gas. Kharkiv. 167-171. (In Russian). Yaremiychuk R.S, Yaremiychuk Ya.S. 2007. Wells completion. Lviv: Center of Europe. 368 p. (In Ukrainian).

ADAPTATION OF A GAS POOL MATERIAL BALANCE TO THE DYNAMICS OF GAS PRESSURE CHANGES

Based on the analysis of the main methodological uncertainties in the material balance method, their influence on errors in the estimation of the drained volume of a gas pool depending on the stage and actual information about its operation is determined. An important aspect of estimating reserves and predicting technological indicators of gas production is the correct adaptation of the material balance model to the actual history of extraction. Examples of typical cases of adaptation of the forecasting model of gas pools development indicators for the Dnieper-Donets Basin were given in accordance with the actual measurements of reservoir pressure in wells; they indicate the wide possibilities of the method especially at the later stages of pool’s development. Key words: field, development system, material balance, hydrodynamic modelling, engineering solutions, forecasting, formation pressure, well production rate, reserves, formation, approximation, algorithm References Akulschin А.I. 1988. Oil Field Forecasting. М. Nedra. 240 p. (In Russian) Fetkovich M.J. 1971. A simplified Approach to Water Influx Calculation-Finite Aquifer System. JPT. Р. 814-828.https://doi.org/10.2118/2603-PA Instructions for comprehensive research of gas and gas condensate wells. Part Joint Stock Company «Gazprom». 2011. М. 319 p. (In Russian) Kanevskaya R.D. 2003. Mathematical modeling of hydrodynamic processes of hydrocarbon field development. М. Institute for Computer Research. 140 p. (In Russian) Rules of development of oil and gas fields. Order No. 118 of the Ministry of Ecology of Ukraine issued 15.03.17. (In Ukrainian) Zarubin Yu.A.*, Gunda M.V., Nikolaychuk V.V., Lastovetska A.V. 2017. Risks of gas production forecasting, using material balance equations. Journal of Hydrocarbon Power Engineering. Vol. 4. Issue 1. P. 8-17. Zheltov Yu.P. 1986. Oil field development: university texbook. М. Nedra. 332 p. (In Russian)

Huff ‘n’ Puff EOR Proves Effective in Gas-Condensate Reservoirs

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper URTEC-2019-987-MS, “Gas-Injection EOR in Eagle Ford Shale Gas-Condensate Reservoirs,” by Reza Ganjdanesh, SPE, Wei Yu, and Mauricio Xavier Fiallos, SPE, The University of Texas at Austin; Erich Kerr, SPE, EP Energy; Kamy Sepehrnoori, SPE, The University of Texas at Austin; and Raymond Ambrose, SPE, EP Energy, prepared for the 2019 Unconventional Resources Technology Conference, Denver, 22–24 July. The paper has not been peer•reviewed. Copyright 2019 Unconventional Resources Technology Conference. Reproduced by permission. As the pressure drops below the dewpoint in an unconventional gas-condensate reservoir, the liquid drops out of the gas phase and forms an oil phase in the matrix and fracture. The volume of the oil phase formed in the matrix mostly stays below the residual oil saturation. The gas huff ‘n’ puff process has demonstrated potential in improving recovery from tight oil reservoirs. The objective of the study described in this paper was to investigate the feasibility of huff ‘n’ puff enhanced oil recovery (EOR) in a•gas-condensate reservoir. Introduction Compositional analyses of fluid samples, taken from early production of three wells located a few miles apart from each other in Eagle Ford, were used to build the black-oil, volatile-oil, and gas-condensate fluid models. The produced field gas was selected as the only viable option for injection. Phase-Behavior Models The phase-behavior models were built for black-oil, volatile-oil, and gas-condensate wells on the basis of pressure/volume/temperature reports from bottomhole samples. The reservoir fluids were built by combining mathematically the oil and gas fluids from separators. The pseudocomponents were characterized from the detailed compositional laboratory analysis. The Peng-Robinson equation of state with the temperature-independent volume correction was used for phase-behavior modeling. The Lohrenz-Bray-Clark viscosity model was applied in calculating the phase viscosities. The condensate/gas ratio for the gas condensate fluid is 147 STB/MMscf, which is a rich gas-condensate fluid. Comparative Study of Gas Injection To compare the performance of huff ‘n’ puff gas injection in different fluid types, single-well simulation models were built for each fluid type. Several well models of 4,500 ft in length with a fracture spacing of 50 ft were built using a compositional simulator. The reservoir thickness was 130 ft. The hydraulic fractures were set up using the embedded discrete fracture model (EDFM) preprocessor. Each single-well model was history matched using the production data. Because the history-matching solutions were nonunique, the rate and pressure transient analysis for each well were used to limit the results to the realistic solution spaces. The history-matched fracture half-length varied between 50 and 175 ft and the fracture height varied between 50 and 90 ft. The fracture conductivity ranged between 3–30 md-ft. The history-matched models were used to investigate the performance of gas-injection EOR for all fluid types. The field gas was injected for 10 cycles, and the cumulative produced oil using huff ‘n’ puff was compared to one without gas injection. The incremental oil recovery for the nine studied black-oil cases varied between 30 and 40%. The incremental oil recovery was less than 10% for three volatile-cases and 15 to 20% for 13 gas-condensate ones.

An Investigation into Sub-Critical Choke Flow Performance in High Rate Gas Condensate Wells

There have been some correlations in the literature to predict the gas and liquid flow rate through wellhead chokes under subcritical flow conditions. The majority of these empirical correlations have been developed based on limited production data sets that were collected from a small number of fields. Therefore, these correlations are valid within the parameter variation ranges of those fields. If such correlations are used elsewhere for the prediction of the subcritical choke flow performance of the other fields, significant errors will occur. Additionally, there are only a few empirical correlations for sub-critical choke flow performance in high rate gas condensate wells. These led the authors to develop a new empirical correlation based on a wider production data set from different gas condensate fields in the world; 234 production data points were collected from a large number of production wells in twenty different gas condensate fields with diverse reservoir conditions and different production histories. A non-linear regression analysis method was applied to their production. The new correlation was validated with a new set of data points from some other production wells to confirm the accuracy of the established correlation. The results show that the new correlation had minimal errors and predicted the gas flow rate more accurately than the other three existing models over a wider range of parameter variation ranges.

Choice of optimal technological operation mode of off-shore gas-condensate wells exploited in complicated conditions

The object of research is a new method for the approach to control the optimal technological regime of gas and gas condensate wells. It is noted that in order to optimize the technological regime of the well, by extracting liquid and solid particles, it is necessary to know the minimum value of gas production or gas flow rate, which, in turn, is provided by determining the corresponding value of the bottomhole pressure. To determine the bottomhole pressure at which the well reaches the optimal operating mode, an equation is obtained that has a complex structure with respect to the bottomhole pressure (pressure in the elevator shoe), for the solution of which the graphoanalytical method was used. The proposed method for optimizing the operation of gas and gas condensate wells was tested on the basis of actual data. And it is shown that it is possible to determine the optimal operating mode of gas and gas condensate wells by determining bottomhole pressure values at which liquid and solid particles are transported from the bottom of the wells to the earth's surface. In this case, the initial data for wells (No. 652 and 704) operated on the VII horizon of the Sangachal-Sea-Duvanny-Sea-Khara-Zira (Azerbaijan) field is used to determine their technological regimes. It is shown that it seems possible to increase the productivity of offshore gas and gas condensate wells by changing the design of their lifts and the proposed method allows to extract liquid and solid particles from the trunk to the earth's surface. For each case, the particle deposition rates in the gas medium and the gas flow rate in the elevator shoe were calculated. Judging by the value of the difference in the determined particle deposition rates and gas flow in the elevator shoe, the possibility of the formation of liquid plugs in the well is established. If a situation arises when the gas flow rate does not ensure the extraction of liquid particles on the earth's surface, it is proposed to change the diameters of the lifting pipes.

Development of inflow performance model in high temperature gas-condensate reservoirs

Inflow Performance Relationships (IPRs) are important element for reservoir engineers in the design of new wells and also for monitoring and optimizing existing wells. IPRs are used to determine optimum production of gas rate and condensate rate in a well for any specified value of average reservoir pressure and predict the performance.Jokhio and Tiab proposed a simple method of establishing IPR for gas condensate wells. The method uses transient pressure test data to estimate effective permeability as a function of pressure. Effective permeability data used to convert production bottomhole flow pressure into pseudopressure to establish well performance. Despite the effectiveness of the method, single phase correlations were used in PVT calculations of each phase, which over simplified the fluid flow in gas condensate wells. Single phase dry gas equations do not reflect the multiphase flow behaviour of gas condensate wells below the dew point. Due to this limitation Jokhio and Tiab method modified by this study and new analytical IPRs for gas condensate well proposed.The major improvement of the above method is incorporating new viscosity correlation developed by this study and using two-phase compressibility factor as key parameters for predicting gas condensate inflow performance. Therefore, the main contribution of this study is development of viscosity correlation which is a critical issue in predicting gas condensate inflow performance both above and below the dew point. Optimization techniques and nonlinear regression used to develop a new viscosity correlation for high temperature heavy gas condensate reservoirs under depletion.The application of the new model is illustrated with field example for current IPR curves. Compositional simulation study of the well performed in PIPSIM simulator. The proposal approach provides reasonable estimates of simulator input reservoir properties (e.g. IPRs). Accuracy of the new method compared with compositional simulation study. The proposed method presents average absolute relative deviation (AARD) of 5.8% for gas IPR and 7.5% for condensate IPR compare to compositional simulation results. New method provides a tool for quick estimation of gas condensate wells without need of relative permeability curves and expensive and time consuming compositional simulation.

RESULTS OF INFLOW INTENSIFICATION AT THE URENGOY FIELD

Background The article discusses the results of the intensification of the inflow at Urengoy oil and gas condensate field. It is shown that the most successful method of inflow intensification is hydraulic fracturing. During the further exploitation of the field, the hydraulic fracturing will be the main effective method of intensifying the gas condensate wells inflow. Aims and Objectives To assess the methods of inflow intensification used at Urengoy oil and gas condensate field. Results The analysis of the applied methods of inflow intensification at Urengoy field has been performed. The most frequently used methods of stimulation of inflow are considered. It was established that the main effective method of intensifying inflow of gas condensate wells at Urengoy field in the near future (within 2-3 years) will be hydraulic fracturing, including through delayed development technology use. Nevertheless, it is necessary to note that the situation largely depends on the effectiveness of the geophysical and hydrochemical control system and qualified geological and technical solutions.

Алгоритм определения объемных долей газа, воды и конденсата в продуктах добычи газоконденсатных и нефтегазоконденсатных скважин с высоким содержанием жидкой фазы

Алгоритм определения объемных долей газа, воды и конденсата в продуктах добычи газоконденсатных и нефтегазоконденсатных скважин с высоким содержанием жидкой фазы

Применение многофазной насосной установки для решения проблемы обводнения газовых и газоконденсатных скважин

Применение многофазной насосной установки для решения проблемы обводнения газовых и газоконденсатных скважин

UAE Case Study Highlights Challenges of a Mature Gas-Condensate Field

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 188422, “Well-Integrity Management: Challenges in Extending Life of a Mature Gas-Condensate Field—A Case Study,” by S. Jain, M.A. Al Hamadi, H. Saradva, SPE, and J. Asarpota, Sharjah National Oil Company, and S.J. Sparke, SPE, M. Volkov, and H. Abu Rahmoun, TGT Oilfield Services, prepared for the 2017 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, 13–16 November. The paper has not been peer reviewed. Three onshore fields in the Emirate of Sharjah, United Arab Emirates, have more than 30 years of production history from more than 50 gas-condensate wells. While existing resources could be recovered by drilling additional wells, the most economical solution would be to confirm that existing well stock has sufficient well integrity to allow the continued use of these wells safely. Introduction The Sajaa asset consists of three retrograde condensate onshore fields. All wells are naturally flowing, with support from wellhead compression to reduce the effect of liquid loading on these mature gas producers. The reservoir was blown down to produce gas associated with rich condensate, water, and liquefied petroleum gas. With the reservoir’s long production history, its pressure has been greatly reduced. Through use of a highly simplified upstream production technique, the wells continue to produce condensate-rich gas with the low-pressure regime. But, because of the reservoir-pressure decline, the production rate remains reduced. Therefore, surface gas compression is required to reduce backpressure and pump the gas to a nearby production facility for separation and, ultimately, custody transfer and sale. Mature Well Status The asset wells were completed with 5-in. tubing along with a nominal 7-, 9-, and 13-in. completion scheme. For production-optimization purposes, 10% of the wells produce directly up the production casing, while all the wells are completed packerless. The main purpose of the open annulus completion was to avoid the extensive problems and costs encountered previously with packer completions in the hostile environment and allow for chemical corrosion inhibition along the conduit of the A annulus (Fig. 1). The cement behind the casing is generally accepted as accomplishing vertical isolation, though not radial isolation, with the natural pore pressure being applied laterally through the cement as a worst case. Collapse is considered to be more critical as a parameter than burst during production, even more so in mature reservoirs with cemented barriers that support against burst conditions. Actual well-integrity failures in a well stock do not always imply a situation in which uncontrolled flow of fluids reaches the surface. Individual barrier failures in a specific well group depend on a variety of factors, such as geographical area, operator, drilling era, well type, and maintenance quality. Gas is expected to be the primary fluid lost when a multibarrier failure occurs. The Sajaa asset features comprehensive active and passive barrier systems. Cemented-to-surface annuli and heavy-duty wellheads account for the passive barriers; continuous remote monitoring of the annuli and weekly visits to the well location are effective active barriers.

Система автоматического регулирования режимов газовых и газоконденсатных скважин – элемент концепции интеллектуального промысла

Система автоматического регулирования режимов газовых и газоконденсатных скважин – элемент концепции интеллектуального промысла