Day 2 Wed, March 27, 2019最新文献

{"title":"Integrating Effective Services into MRC Technology to Rejuvenate Mature Reservoir with Low Permeability and Low Resistivity","authors":"Feng Li, Xiong Xie, Li Huang, Luyao Zhou, B. Chang, Chao Wang, Fei Wang, Chengwen He","doi":"10.2523/IPTC-19158-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19158-MS","url":null,"abstract":"\u0000 In China, the main sandstone reservoir M of the LF oilfield entered the mature development stage with high water cut (average 93%) and 66.1% recovery. Remaining oil exists vertically in the H layer at the top section of this massive bottomwater reservoir and laterally at margins of current development area with less well control. The H layer consists of several thin (0.5 to 2 m) sand sublayers interbedded with calcareous tight sublayers with low permeability; the effective oil drainage radius of single borehole is 100 to 150 m. Maximum reservoir contact (MRC) technology was employed to increase drainage area and volumetric sweep efficiency for optimal production and recovery to rejuvenate this mature reservoir.\u0000 In an original hole with 98 to 99.9% water cut targeted for a workover operation, two new laterals were sidetracked to comprise a three-lateral MRC configuration with openhole completion to develop the SL1 target sublayer of the H layer. The success of MRC wells depends on an efficient openhole sidetrack and azimuth turning. Moreover, multilaterals need to precisely chase the sweet zone in the reservoir. Drilling into overlying shale causes borehole collapse, and penetrating the underlying tight zone causes fast bottom water breakthrough. Low resistivity contrast increases the difficulty of distinguishing the target zone from the shoulders. Sparse well control and limited seismic resolution bring high structural and stratigraphic uncertainties. Accordingly, effective services were equipped to overcome these challenges to achieve the required engineering and reservoir objectives. The new-generation hybrid rotary steerable system (RSS) tool provides stable, rapid, and accurate steering control, even with high dogleg severity, to achieve engineering objectives. With a balance between resolution and depth of investigation (DOI), high-definition deep-looking resistivity inversion uses the Metropolis coupled Markov chain Monte Carlo method to clearly identify multiple layers (more than three) within an approximately 6 m DOI, formation resistivity distribution, anisotropy, and dip, even in this low-resistivity-contrast environment. Reservoir details could be clearly unveiled to help MRC lateral steering along the thin target. Furthermore, a wide-range-displacement electrical submersible pump (ESP) helps optimize openhole performance.\u0000 Six new laterals were drilled in three MRC wells. Hybrid RSS tools provided 100% openhole sidetrack success rate, and laterals were turned laterally with 15 to 70° azimuth change and 200- to 570-m displacement to maximize the drainage area. Deep-looking inversion revealed high-definition reservoir details by delineating three key boundaries and four adjacent layers' profiles simultaneously and identifying target zone's thickness and property variation. The target sand is 0.5 to 2 m thick with resistivity of 2 to 9 ohm-m, surrounded by interbeds with resistivity 8 to 10 ohm-m. Within the refined 3D reservoir model","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127279385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive Seismic Data Conditioning of the Bioclastic Limestone in the Middle East","authors":"Tengfei Lin, Xueling Wang, Junchang Dong","doi":"10.2523/IPTC-19228-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19228-MS","url":null,"abstract":"\u0000 The bioclastic limestone reservoirs of Cretaceous period occupy an important position in the petroleum industry of Middle East. It is the carbonate heterogeneity that is challenging the accuracy of the reservoir prediction, which brings forward higher requirements for the seismic data quality. Besides, some seismic data are processed more than 10 years ago, the signal to noise ratio (SNR) is relative low due to the random noise and coherent noise like acquisition footprint anomalies. The acquisition footprint artifacts caused by acquisition and processing seriously suppress the true stratigraphic features, which can result in pitfalls in seismic interpretation, seismic attribute analysis as well as seismic inversion. While the pre-stack seismic data is usually unavailable, which means that the noise can hardly be subtracted by conventional pre-stack seismic processing workflows, such as statics, high-resolution velocity analysis and ground roll attenuation. Consequently, a comprehensive post-stack seismic data conditioning workflow is necessary to solve the above problems.\u0000 In order to improve the post-stack seismic data quality, a comprehensive data conditioning workflow are applied for noise suppression. Firstly, structural-oriented filtering is utilized to attenuate random noise and partial acquisition footprint artifacts. Then 2D waveform transform of seismic amplitude and filtered seismic attribute in x-y domain are calculated, to separate acquisition footprint anomalies (large wave number in kx-ky domain) from true structural signal (small wave number in kx-ky domain) by interactive analysis. The application of Laplace-Gaussian (LoG) filter deserves an obvious improvement in acquisition footprint suppression workflow. The comprehensive noise attenuation workflow in this paper can effectively remove both periodic and non-periodic noise to obtain higher signal to noise ratio (SNR) for post-stack seismic volume. In this way, the stratigraphic features (tidal-channel, reef-beach complex) can be more clearly depicted and some artifacts caused by noise will disappear in seismic attribute calculation, seismic inversion and reservoir prediction.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122501429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective Annular Ledge Formation Sidetracking in Multilateral Wells in Vostochno-Messoyakhskoye Field","authors":"A. Voronin, N. Abaltusov, A. Vershinin, A. Dmitriev","doi":"10.2523/IPTC-19350-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19350-MS","url":null,"abstract":"\u0000 Multilateral drilling technology offers a highly effective method of enhanced oil recovery in fields characterized by complicated geological structure. This paper describes the analysis of sidetracks in an open hole by annular ledge formation with the use of a downhole motor in multilateral wells in Vostochno-Messoyakhskoye field.\u0000 Since May 2018, more than 130 sidetracks have been drilled in Vostochno-Messoyakhskoye field with the use of bottomhole assembly (BHA) with a downhole motor in open hole by annular ledge formation. The fundamental difference between this method and conventional sidetracking with a downhole motor is that during sidetracking the entire drill string constantly rotates, rather than just bit rotation produced by downhole motor operation. In the process of technology introduction a comparison was made on how different downhole and geological conditions influence the time and performance results.\u0000 The technology introduction resulted in the sidetracking time reduction from 9 hours to just 3 to 4 hours.\u0000 A number of additional advantages of sidetracking with annular ledge formation were confirmed in the process of operations:\u0000 The constant rotation of the drill string enables smooth weight transfer to the bit smooth, without failures. This contributes to effective and uniform ledge formation. Such sidetracking can be carried out at an extended length of open hole when it is difficult to ensure a free movement of the BHA which is necessary of conventional sidetracking. Constant rotation mitigates the risk of differential sticking. More favorable conditions are created for BHA movement in an interval of the holes diversion and subsequently for liner running in. It is possible to sidetrack with the use of a stiff BHA including a complete set of logging tools. In case of conventional sidetracking, it is preferable to use a short and flexible BHA.\u0000 The experience gained in Vostochno-Messoyakhskoye field can be extrapolate to other fields where multilateral wells are drilled with annular ledge formation.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121231308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Yanbei-Unlocking the Tight Gas Green Field Development Potential Through Integrated Technology Application","authors":"M. Z. Zaini, K. Du, M. Zhu, Li Feng, H. Yang, Lin Wei, Y. Liu","doi":"10.2523/IPTC-19265-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19265-MS","url":null,"abstract":"\u0000 Yanbei Project is a tight unconventional gas development that covers a vast area of 2,341 km2 in the Ordos basin – the largest gas producing basin in China. The paper outlines the innovative technologies applied, major achievements and the integrated approach used to successfully develop this large-scale gas greenfield of highly heterogeneous fluvial thin sands with very complicated surface terrains and resources overlaying issues (coal mines and water reservoirs). The project scope calls for drilling and fracturing 784 wells in the full field development in two phases. Phase 1 includes construction of 7 hubs, central processing facilities (CPF), and 360 km of pipelines on a complex hilly topography and aims to deliver production of 1.4 bcm/year. Phase 2 will ramp up to a higher rate. The horizontal well with multi-stage fracture development concept was introduced for the first time in the project and has significantly improved both single well productivity and project economics. More than 20 different technologies, ranging from subsurface, drilling, logging, completion, stimulation, production and facilities, have been applied each of which has been carefully assessed to ensure its value to the project. The advanced 2D seismic technologies have enabled the project to successfully reprocess and interpret a complicated 2D seismic dataset that is heavily distorted by the hilly terrains. The integration of the 2D seismic interpretation with a variety of subsurface and drilling datasets have enhanced the understanding of reservoir characterization and sandbody architectures hence significantly reduce geological risks in drilling horizontal wells in such a complex fluvial system. The drilling and surface engineering work have dealt with a variety of different challenges such as well pad acquisitions, conflicting with coal mines & surface water reservoir areas along with local community issues. One of the key success factors for the project is the integration of the industry's worldwide expertise of technologies, procedures and HSE standards coupled with the local experience, which has ensured an innovative and fit-for-purpose technology-driven solution in planning and execution of the project. The paper describes the main geological and engineering challenges and outlines an integrated approach in applying extensive but selected technologies to resolve those challenges.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126767344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Integrated Approach to Well Leak Diagnostics: Case Study of the Successful Application of the Latest Leak Detection Technology and Interpretation Offshore Timor Sea, South East Asia","authors":"A. Imrie, Brendon Negenman, Chung Yee Lee, M. Iyer, S. Parashar, Mohamed Raouf Shata, Sean Helton","doi":"10.2523/IPTC-19448-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19448-MS","url":null,"abstract":"\u0000 The identification of low-rate leaks along with low annular-pressure buildup rates in any type of completion presents challenges in the well-integrity domain. This paper emphasizes the importance of understanding the well-diagnostic problem to determine feasibility, isolate interest zones, enhance stimulation strategies, and ultimately optimize the acquisition of high-resolution acoustical data from the wellbore with a latest-generation advanced leak-detection tool.\u0000 This case study discusses the methodology that underlies the successful determination of the depths and the radial locations in the outer casing strings of multiple leaks in an offshore well. In the study presented, emphasis had been placed on the job planning to provide adequate or substantial leak stimulation for the accurate determination of the leak points in terms of radial distance away from the tool axis within the wellbore. Rather than a shut-in and flowing or venting acquisition, it was proposed that the optimal method for the successful determination of an outer casing string leak involved invoking a range of flow rates and, therefore, acoustic levels, across an extended period. The study also demonstrates the advantages of integrating acoustic-based tools with conventional production logging tools.\u0000 Two outer string casing leaks with annulus to formation communication areas were identified from high-resolution leak-detection logging coupled with conventional pressure and temperature measurements. The interpretation process included the computation of a 2D radial map of the flow activity across each zone of interest. This process resulted in less ambiguity and clearer results obtained in real time during the acquisition. The location of each leak point was triangulated using an error-minimization algorithm from the received acoustic waveforms at the tool receiver array. Further, the optimized stimulation strategy enabled leak-stimulation responses to be tracked in the computed power spectral density (PSD) at each leak. This process enabled the operator to promptly move on with the well abandonment strategy without waiting for further data analysis.\u0000 Attention to detail from the outset and a complete understanding of the well and its annular pressure and fluid behavior enabled an optimized and focused electric line diagnostic strategy to be used. The use of high-resolution acoustic data from an advanced leak-detection tool with an array of hydrophones ensured that the multiple leak locations were identified and characterized.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126483492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Analysis on Isochronal Facies-Controlled Pre-Stack Seismic Inversion Prediction of Tight Sandstone Reservoir- A Case of Fuyu Formation in Zhaoyuan Area in North Songliao Basin, China","authors":"Meiyi Chen, Qingsheng Ji, Shoutian Chen, L. Qin, P. Cong","doi":"10.2523/IPTC-19130-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19130-MS","url":null,"abstract":"\u0000 Based on the seismic prediction difficulties of the tight sandstone reservoir in Fuyu formation in Zhaoyuan area, single-well sequence division and connecting-well sub-layer correlation are carried out according to logging and lithologic data, and short-cycle interface position is calibrated precisely after a mutual calibration of logging and seismic data. Horizon tracing in the whole area is also carried out to build high-frequency isochronous stratigraphic framework. On this basis, the log facies modes and the sedimentary facies of the short-cycles under a high-frequency isochronous stratigraphic framework are analyzed in the target area, sand-body geometric scale parameters and their relations and sand-body development degree are calculated out, and a sand-body geological model is also built out. According to the seismic data and layer-by-layer geological model of sand bodies, a spatial distribution probability model of facies-controlled sand bodies is built out, which is used to constrain the pre-stack seismic data in facies-controlled inversion calculation. Based on the results of facies-controlled inversion, the tight sandstone prediction is carried out. Finally, a method of isochronal facies-controlled pre-stack seismic inversion prediction of tight sandstone reservoir is formed and it realizes the effective prediction of superimposed sand bodies in target area. Compared with actual drilling results, the sandstone of more than 2m has clear depiction and the sandstone of between 1-2m also has response, which indicates that this method is feasible and practicable.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127967307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Dilation-Recompaction Model in Fracturing Optimisation in Tight Oil Reservoir","authors":"Rui-Sen Gao, Xin Wang, Zhen Yang, Q. Zhan, Wei Zheng, Y. Liu, Li Yang, Zhe Liu, Zhen Wang","doi":"10.2523/IPTC-19431-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19431-MS","url":null,"abstract":"\u0000 Tight oil and gas reservoirs are characterized by strong heterogeneity, poor physical properties, low single well production, difficult development and others. The volumetric stimulation fracturing technology has become a key technology for the effective utilization of tight reservoirs. In the current fracturing optimization design, there are some limitations in simulating the true pattern of fracture propagations because the geological model is relatively simple and it is not necessary to consider the heterogeneity of reservoir plane. At the same time, the effect of large-scale and large-volume injection of fracturing fluid on formation permeability field cannot be neglected in the volume stimulation, and the coupling relationship between fracturing fluid loss and reservoir seepage is not considered in conventional productivity simulations so that the effective stimulated reservoir volume (SRV) cannot be calculated accurately. In this paper, a numerical simulation technology of fracturing based on rock deformation is introduced through theoretical analysis and field application. The effective SRV is analyzed quantitatively, and the optimization simulation method of volume stimulation parameters with the effective SRV as the evaluation objective is formed preliminarily, which guides the fracturing design of volume stimulation in tight oil blocks.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"12 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132610398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Separator Pressure Optimisation and Cost Evaluation of a Multistage Production Unit Using Genetic Algorithm","authors":"M. Motie, P. Moein, R. Moghadasi, A. Hadipour","doi":"10.2523/IPTC-19396-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19396-MS","url":null,"abstract":"\u0000 Once reservoir fluid is brought to the surface it is separated to discrete streams of oil and gas in production unit. This should be conducted with consideration of maximizing oil production and to decreasing total costs as well. The regulation of separators pressure is a key point to achieve the highest oil recovery in this process. In addition, estimating the optimum number of separation stages, would augment the design of production plant economically. Adjusting separator pressure is usually conducted by employing PVT data which are provided through flash or equilibrium separation tests. In case of experimental tests unavailability, an alternative method could be empirical correlations. However, such tentative methods contain inaccuracy and are also time consuming which may limit their utility. In this study the issue was addressed by applying genetic algorithm (GA) as well as flash calculation through a case study on one of Iranian oil field. It has been tried to optimize set point pressures of each stage and enhance liquid share of the fluid with respect to minimized gas oil ratio (GOR). Prior to this, four scenarios were considered for determining the number of separation stages. To determine the prime scenario, a cost evaluation was implemented which leaded to the selection of four-separator scenario as the most economical case.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132735558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated Geology Sweet Spot and Microseismic Monitor to Optimise Reservoir Stimulation - A Case for Shale Gas, China","authors":"Wei Liu, Z. He, Junxing Cao, Jianjun Zhang, Gang Xu, Xiaoping Wan, Gang Yu","doi":"10.2523/IPTC-19197-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19197-MS","url":null,"abstract":"\u0000 Shale play, as one kind of non-conventional natural gas resource, has become the focus of domestic and overseas research in recent years. shale is pertained to be a reservoir with an ultralow porosity and permeability, its occurrence mode, accumulation pattern of natural gas, as well as development model are remarkably different conventional oil gas reservoirs, its development must be implemented by some special technique, e.g. horizontal drilling, drilling geologic steering, hydraulic fracturing, microseismic monitor, etc. Research shows, shale gas production depends on two factors, one is geological sweet spot factor, e.g. Total organic carbon, brittleness, core fluid pressure, micro-fractures, high quality shale thickness etc., the other is engineer technique factors, e.g. horizontal drilling, drilling geologic steering, hydraulic fracturing, microseismic monitor, fracturing schemes, etc. Single factor, sweet spots or engineering technique factor often not guarantee shale gas highly production, only when the most optimal combination of both, can achieve shale gas production maximization. How to integrate sweet spots and engineering technique to guide shale gas exploration and development? This is a serious question. This question involves to many fields, including geology and engineer sweet spots, horizontal well location deployment, drilling geologic steering, pre-fracturing warning and design, hydraulic fracturing design real-time adjustment, microseismic monitoring, etc., sweet spots results runs through the entire shale exploration and development. In this article, we will pay more attention to demonstrate that how to adjust the fracturing scheme and optimize the reservoir stimulation in real time by integrated geological sweet Spot and microseismic monitor.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128110363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved Gas Recovery for Bottom-Water-Drive Gas Reservoir Using Downhole Water Drain Technique: A Success Story from Arthit Field, Thailand","authors":"Sutthipat Phummanee, A. Rittirong, W. Pongsripian, Natthaphat Phongchawalit","doi":"10.2523/IPTC-19488-MS","DOIUrl":"https://doi.org/10.2523/IPTC-19488-MS","url":null,"abstract":"\u0000 The objective of this paper is to demonstrate the implementation of downhole water drain (DHWD) technique to improve gas recovery factor for bottom-water-drive gas reservoir in the multi-thin reservoirs system in Arthit field. This technique was selected as an alternative method to defer water loading in the wellbore by preventing early water breakthrough meanwhile enhancing gas expansion. Project planning, operation, and performance evaluation are the gist of the discussion here.\u0000 Candidate selection was the critical first step to the success of DHWD technique. The suitable wells require a gas-water contact reservoir at the upper part of the well and totally depleted reservoirs below it. After identifying candidates, bottomhole pressure survey was performed to investigate the reservoir condition for reservoir simulation. Both gas and water layers above and below the gas-water contact were perforated as designed. A plug was set between the perforated gas and water layers to isolate the flow. This allows gas to be produced to surface while water flows downwards to the depleted reservoirs.\u0000 The key parameters used in evaluating the effectiveness of DHWD technique are incremental gas recovery and water breakthrough time. According to the production history of existing gas-water contact reservoirs in Arthit field, massive water production generally starts to intrude after 1.35 months of production at which water-gas ratio increases above 50 STB/MMscf. As a consequence, the gas production sharply declines and eventually ceases to flow. The water breakthrough time of the two trial wells in which DHWD technique was applied is significantly slower than the field average. One was observed water breakthrough after 2.05 months and the other was after 5.40 months of the production. Gas EUR gain is the difference between the EUR when applying DHWD technique by declined curve analysis and the expected EUR of conventional production by statistical method. The results from the two trial wells indicate that DHWD technique can significantly improve the EUR by 110% and 871%.\u0000 Downhole water drain is a groundbreaking technique that can be practically implemented to enhance gas recovery of bottom-water-drive gas reservoirs. This technique is recommended for gas field as an alternative strategy since it yields substantial additional reserves gain while required only a small additional cost from the additional perforation of water sand and permanent bridge plug.","PeriodicalId":105730,"journal":{"name":"Day 2 Wed, March 27, 2019","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123934791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}