bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D Simulation of Low Salinity, Polymer, Conventional, Water-flooding & Combination IOR Methods – Heterogeneous & Varying Wetting Conditions
Authors: Aladasani Ahmad , Bai Baojun , Wu Yu-Shu , Okasha Qutaiba 
Published: October 2015

Abstract
In this paper a five spot well patterns is used to study Low Salinity, Polymer, Conventional, Water-flooding and the combination of Polymer flooding and LSWF. The aforementioned cases are applied under different wetting conditions. Oil recovery is a function of reservoir forces. Effective IOR implementation requires the proactive identification and contribution of the dominating reservoir forces, over the course of the field development. The work in this paper uses a validated, compositional simulator in addition to validated relative permeability and capillary formulations to simulate LSWF, PF, Conventional, Water-flooding and combination of PF + LSWF in a multi-dimensional, anisotropic and aerially heterogeneous model, under various wetting conditions. Wettability modification is also simulated using start and end relative permeability, captured and validated from literature.
The initial wetting state is an important criterion for LSWF. The incremental recovery in oil-wet systems, or "typical carbonate reservoirs," is more rapid and thus requires less dilution of the injected brine salinity. In addition, simulation results indicate substantial un-swept quantities of available oil saturation. Therefore, the role of polymer flooding is examined along with conventional water-flooding in wetting conditions where LSWF may not achieve significant incremental recovery. LSWF is not effective in intermediate wetting conditions and Polymer flooding yields higher recovery factors in all water wet conditions.
The impact of reservoir damage has an adverse effect on the development's recovery factor and polymer flooding yields the highest incremental recovery in case of low permeability formations. In oil wet conditions the performance of PF and LSWF is similar especially in weak oil wet systems due to the equal contribution of their respective displacement efficiencies. In strong oil-wet conditions the combination of PF + LSWF yields the highest recovery factor. The wetting conditions, formation heterogeneity and permeability magnitude all impact IOR selection and suggest that each oil reservoir has a unique ionic environment that changes naturally and by human intervention, therefore it is important to study different IOR methods at different stages of the field development.
Prediction Method of In-situ Stress in Non-isopachous Ultra-deep Composite Salt-gypsum Formation
Authors: Hou Bing , Chen Mian , Jin Yan , Diao Ce , Lin Botao , Lu Yunhu 
Published: October 2015

Abstract
Soft rocks, such as rock salt, claystone-gypsum, and gypsum, can cause tremendous dangers to wellbore wall surrounding rock deformation and damage. These rocks are the key to predict in-situ stress more accurately in ultra-deep composite salt-gypsum formation and ensure the safety of casing design after drilling or well completion. Therefore, a new method to predict in-situ stress in ultra-deep composite salt-gypsum formation needs to be established.
To date, existing in-situ stress experimental methods are unsuitable for salt-gypsum formation; these methods need in-situ stress data to design drilling and completion casing strength to ensure casing safety in salt-gypsum formation. To solve such problem, this study measured the in-situ stress of rock salt-gypsum for the first time by deformation rate analysis (DRA)–Kaiser method. Results showed that combining DRA and Kaiser methods can increase the credibility of the test data. When the stress–strain difference curve displays the inflection point and the stress–acoustic emission intensity curve has significantly increased point, the stress corresponding to the axial compression is the stress that the rock suffered. This stress avoids displaying several Kaiser points in previous Kaiser effect experiments.
Based on in-situ stress and actual tectonic evolution, a 3D multi-layer complex geological model was established. This model solves the problem wherein the previous model was oversimplified and could not truly reflect the actual geological structure during the simulation process. A numerical method of in-situ stress field for the entire regional composite salt-gypsum formation was developed based on the finite difference method and nonlinear prediction theory. This method solves the problem wherein laboratory experiments and theoretical calculations have difficulty in obtaining the in-situ stress of ultra-deep composite salt-gypsum formation.
According to the study results in this thesis, in-situ stress and casing integrity are evaluated in ultra-deep, high temperature, and high pressure composite salt-gypsum formation in Kuqa piedmont, Tarim Oilfield. Combined with actual situation, the rationality of in-situ stress predicting methods is verified in ultra-deep composite salt-gypsum formation.
Integrated Drilling Database Enables Automated Drilling Engineering Design
Authors: Shi Xiaoyan , Zhou Yingcao , Song Peng , Zhao Qing , Jiang Hongwei , Huo Zongqiang , Yang Guang , Zhai Xiaoqiang 
Published: October 2015

Abstract
As the rapid development of drilling techniques and data acquiring techniques, more and more drilling data are available. Storing, managing and effective using of these massive data are crucial to optimized drilling engineering design and strategic decision. This article is to research and design an integrated drilling database, and then further explore the innovative usage of the available drilling data. Based on the detail analysis of drilling database requirement, this article researched and designed drilling database by three phases: conceptual design, logical design and physical design. In the conceptual stage, the requirements of drilling design data, real-time drilling data and drilling construction data are extracted and analyzed, then E-R model is constructed. In the logical design stage, data tables and table relationship are designed and refined based on the E-R model. In the physical design stage, physical structure is selected for the logical data model to satisfy the application requirement. The designed drilling database is targeted data storage and management basis for drilling engineering design and craft software, real-time drilling software and drilling history management software; it conforms to drilling business process, contains comprehensive and detailed content and has high performance and refined data table structure. The construction of unified drilling database enables the efficient storage of mass drilling data and further data mining and analysis of drilling information. This work further researched the algorithms of automatic drilling engineering design, especially for automatic wellbore geometry design, based on the available data in the database. This article introduced a systematic method to design an integrated drilling database, which supports design data, real-time data and drilling management data. It also proposed an innovative way of drilling engineering design: automated drilling engineering design based on the data in the integrated drilling database and pre-installed rules.
Behaviour Intention Analysis Among Workers at Oil and Gas Company
Authors: Musa R. Abdullah , Fadhli Achmad , Kusminanti Yuni , Erwandi Dadan , Lestari Fatma 
Published: October 2015

Abstract
The study is purposed to obtain the intention of behaviour and contributing factors such as attitude, subjective norm (SN) and perceived behavioural control (PBC) as adopted from belief, attitude, intention and behaviour theory. Data collected through distribute the questionnaires among 436 workers from all levels, top management, middle managers and workers. The safe behaviour intention is 4,37 (index 5) and short cut behaviour (SCB) is 2,59 (index 5). The highest values from index would indicate the positive behaviour. Means beta are attitude 9.22 (index 25); SN 18.95 (index 25) and PBC 4.30 (index 5). It may be seen that the most contributing factor is PBC. The study concludes that the implementation of safe behaviour in the company is already good and influenced by external factors (PBC) rather than internal or individual factors (safety attitude). Safety behaviour intention may be improved by increasing the awareness, responsibility and HSE competency among workers. It should be supported by effective supervising and effective safety leadership in every level of management.
Synthesis and Evaluation of Gas-Wetting Alternation Agent for Liquid-Blocking Effect in Condensate Gas Reservoirs
Authors: Jin Jiafeng , Wang Yanling , Zuo Jiaqiang , Dai Caili , Wang Kun , Jiang Ling , Ren Jinheng , Ma Hanqing 
Published: October 2015

Abstract
Liquid condensation near wellbore region may kill gas production in gas-condensate reservoirs when pressure drops to lower than its dew point. One potential way to overcome this problem is to alter reservoir wettability to gas-wetting to reduce condensate accumulation in the near wellbore and maintain high productivity. It was believed that condensate accumulation can be removed by altering the wettability of reservoir from liquid-wetting to gas-wetting. The aim of this study was to investigate the effect of wettability alternation on condensate gas recovery efficiency in porous media.
Different molar ratios between fluorine-containing copolymer monomer and acrylic monomers were used to synthesize a gas-wetting alternation agent. Then Contact angle measurement and Owens two-liquid method were conducted in the laboratory, meanwhile, the effects of alternation agent concentration, salt concentration, pH and temperature on the gas-wetting core were evaluated.
Results showed that when the molar ratio of fluoropolymer monomer: acrylic acid was 1:2, the synthetic product could alter the wettability of core from liquid-wet to preferential gas-wetting. The contact angles of brine and oil can be altered from 23° and 0° to 137° and 90° by 1wt% FP-2 treatment, respectively, the surface free energy of core was improved from 67.52 to 1.66mN/m, the wettability of core was altered into in neutral gas wetting. And the treated cores can keep neutral gas-wetting within a condition of 100000mg/L, 120°C, pH=5~7. This novel gas-wetting alternation agent can be used to solve the problem of liquid blocking effect in gas condensate reservoirs and thus improve gas recovery.
Indonesia's Top 7 Energy Issues: Focusing on What Really Matters
Authors: Saputra Edi 
Published: October 2015

Abstract
The Indonesian government faces numerous challenges. Given the government's resources are limited, it is important to focus on the essential ones, prioritising the crucial issues over the incidental ones, the urgent initiatives over the trivial matters.
Identifying the key issues will enable the government to put the right focus in the right places, to mobilise the people, resources and finances in the right direction. In the light of this, this paper identifies seven key energy issues which should be given the highest priority by the government and other relevant stakeholders.
An Integrated Method for Remaining Oil Prediction Based On Time Lapse Seismic Inversion and its Application
Authors: Linggao Li , Lideng Gan , Zhangxin Zhangxin , Wenhui Du 
Published: October 2015

Abstract
An integrated solution is presented to take good advantage of time lapse seismic data and reservoir simulation results to delineate the potential area of remaining oil. First, a coupled time-lapse AVO inversion method is presented and applied to a test area of time-lapse seismic project in DQ oilfield and resulted in two vintages of elastic properties for each survey. Second, volumes of a direct hydrocarbon indicator (DHI) are calculated from each vintage of elastic properties. An empirical equation of relative DHI variation with remaining oil reserves is obtained. Such empirical equation is then used to predict the change of remaining oil between two acquisitions. At last, the predicted remaining oil change and remaining oil of base survey from numerical simulation is used to circle the potential area of residual oil.
New Nano-Geopolymer Cement System Improves Wellbore Integrity Upon Acidizing Job: Experimental Findings
Authors: Ridha Syahrir , Yerikania Utami 
Published: October 2015

Abstract
Acid stimulation job is one of alternative technique used to improve well productivity. However, improper usage and design of this method may pose problems to the cements surrounding the perforation area of the well and it may lead to well integrity problems. Therefore a good the cement system must exhibit the physical and chemical properties that are not reactive to most types of acids used in acidizing job. This paper developed a new nano-geopolymer cement containing portions of nano-scales of silica, flyash and alkaline liquid under geopolimerization process.
The experimental work is simulated under downhole conditions at pressure up to 4000 psi and temperature up to 120°C. Strength buildup profile was analyzed using Ultrasonic Cement Analyzer. This research also exposed cement samples into acidic environment of mixed HCL and HF with the ratio of 12% and 3% up to 24 hours. Curing times conditioned to be varied along the test to better describe the chemical and mechanical changing due to acid. Advanced Scanning Electron Microscopy (SEM) is used to describe microstructure deformartions of cement samples.
Compared to class G cement, pure geopolymer and nano-SiO2 geopolymer cement have better acid resistance as they experienced less strength loss. It is found that nano-SiO2 possessed the tendency on enhancing pure geopolymer cement property through the strength test. Although the strength degraded, the strength loss is not as much as class G and high initial strength value of nano-SiO2 geopolymer cement gives benefit in maintaining high strength value after acidizing. Sample NG1 with 1% nano-SiO2 obtained the highest strength value and minor crack after 24 hours acid exposure.
The result shows that the new cement system can improve the wellbore integrity by resistingacid alteration and penetration upon acidizing job. At the same time the CO2 emissions from producing conventional API cement can be eliminated by the new nano-geopolymer cement.
Indonesia Wellwork Performance Management and Evaluation
Authors: Prasetya Afriandi Eka , Herputra Shanni Ardhana 
Published: October 2015

Abstract
There are 63 work areas in Indonesia producing 800,000 barrels of oil per day. Workover and well service or wellwork activities are carried out by PSC Contractors as one of backbone activities which compensates production decline. As a state institution for upstream petroleum activities in Indonesia, SKK Migas is responsible to manage and evaluate the performance of wellwork activities to serve the purpose of maintaining national production.
More than 31,000 wellwork activities are performed annually and contribute to the production of more than 40,000 bopd. 2015 program is at 36,000 activities to contribute production target of 50,000 bopd. All wellwork activities are reported to SKK Migas by the PSC contractors in the form of a spreadsheet. SKK Migas evaluates the wellwork performance to be used as consideration in wellwok program approval for the following year. The evaluation includes numbers and types of activities, time and cost, and the contribution to production.
During 2013 and 2014, SKK Migas managed to collect reports from PSC Contractors which consists of more than 60,000 wellwork activities. Based on the evaluation, SKK Migas also give appreciation to the PSC contractor who has the best performance on wellwork activities.
This paper will illustrate how SKK Migas manages large scale wellwork activities in Indonesia using spreadsheet. This paper also illustrate how historical performance is compared, evaluated and analyzed for forward planning of wellwork activities.
Successful Application of Unique High-Density Water-Based Drilling Fluid Used in Zhaotong Shale Gas Horizontal Wells
Authors: Yan Lili , Li Congjun , Zhang Zhilei , Wang Jianhua , Xu Xianguang , Sun Jinsheng , Su Yinao 
Published: October 2015

Abstract
Shale-gas plays have gained significant importance in China. Sichuan Basin, industry's primary focus for shale gas, has finished hundreds of wells. The employed drilling fluids for drilling shale horizontal wells here are mostly oil-based muds (OBMs), due to its well-known excellent performance and the considerable geologic structural complexity. With the implementation of new national environmental law, the application of OBMs will be limited. A pressing goal is to develop a high-performance and environmental-friendly water-based mud.
This paper discussed the research and application of a novel high-performance water-based mud for shale gas horizontal wells in Zhaotong area of Sichuan Basin. The morphology, mineralogical composition, Porosity and cation exchange capacity of the shale samples, and the key technical problems in the target formation were first analyzed. Then, a novel hybrid silicon shale inhibitor, rigid nano-polymer plugging agent, liquid filtrate loss control agent and liquid lubricator were prepared, respectively. Incorporated with other selected agents, an innovative water-based drilling fluid (HPWBD) with a density of 2.2 g/cm3 was formulated and applied.
Extensive lab work was carried out to compare the properties of HPWBD with field oil-based drilling fluid. The results show that HPWBD had excellent inhibitive and lubricant properties, closing to the oil-based drilling fluid. Besides, HPWBD was highly plugging and rheology stable after rolling at 100 oC under high density conditions. Then, the HPWBD was applied successfully in Huangjinba YS108H4 well. The drilled horizontal well interval reached a length of about 1500 m. During drilling, no downhole troubles were observed, no bit balling was found, the borehole diameter was regular, and the electrical logging operation was successful just at the first time. Meanwhile, it reduced cost and environmental concerns associated with cuttings transportation and disposal.
In a word, the developed high-density water-based drilling fluid showed outstanding performances, closed to oil-based muds. Moreover, it was beneficial to the environment and could reduce the cost significantly. It will provide an alternative to oil-based mud for safe and environmental development of shale gas in China.
Shifting the Paradigm: ESP with Induction and Permanent Magnet Motor Application in Low Productivity and High GLR Wells
Authors: Dwitiya Dipta , Hamzah Kamal , Prakoso Noke Fajar 
Published: October 2015

Abstract
With the imminent decline in gas availability for continuous gas lift operations, Kaji Field, Rimau Block, south Sumatra, Indonesia needed a new lifting method to replace gas lift utilized in marginal wells which produce from Telisa formation (sandstone). This project aimed to evaluate the applicability of electrical submersible pumps (ESP) in wells that are not commonly produced with ESP, and was divided into two phases. The first saw the implementation of an existing ESP with several completion modifications, and the second involved a trial of ESP with the permanent magnet motor system (ESP PMM), which at the time of implementation was a newly applied technology in Indonesia.
The alternative artificial lift (AL) configuration had to be operable in wells with low productivity (Productivity Index less than 1 bbl/psi) and have excellent gas handling capabilities (GLR above 3,000 scf/bbl). This presented a stern challenge for the application of submersible pumps due to their basic nature of operating in high liquid rates. Therefore change management also became a crucial agenda in the project. Furthermore, the technology had to be more energy efficient because power generation was also an issue related to the decline in the availability of gas for fueling Kaji's power plants.
The first phase saw the installation of the first ESP unit equipped with an induction motor. The low influx and gassy condition of the well was mitigated by setting the pump below perforation to improve pump submergence. A shroud was also utilized to support natural separation of gas before entering the pump intake, and it also helped in creating fluid velocity to provide the motor with sufficient cooling effect. This configuration resulted in excellent productivity within its first one hundred days of production, providing a cumulative oil production equal to twice the amount when produced using gas lift, i.e. from 3,983 to 7,999 barrels of oil within the same time duration. The second phase of the project saw a similar completion strategy in a further two wells, this time with ESP PMM. The result was continuous and safe production, providing a production gain of almost 100 BOPD from the two wells, and with a 100% increase in energy efficiency.
This effort has proven ESP's applicability in low influx and high GLR wells, and most importantly has prevented production loss caused by forced shutins from gas lift insufficiency. This provided valuable information for further decisions regarding installations and configurations of artificial lift in Kaji Field and other similar fields, and has allowed us to make the decision to progress further with the transition from gas lift to ESP as the main artificial lift of the field, ultimately supporting the effort to sustain production.
Geomechanics Improves Drilling Operations and Reduces Non-Productive Times (NPT) in Kilo Field, Offshore Northwest Java
Authors: Ong See Hong , Power William L. , Sitio Aprianto , Tanjung Erwindo 
Published: October 2015

Abstract
Recent drilling of moderately to highly deviated development wells in the Kilo Field has proven to be extremely challenging. Numerous lost-time incidents including stuck pipe, pack-off, and difficulties in running casing were experienced, particularly when drilling through the Main-Massive Formation. Earlier analyses pointed to mud material quality issues, but drilling performance benchmarking with other nearby fields ruled out this explanation. Faced with continually high NPTs, a geomechanical study was initiated to mitigate the wellbore instability problems. The recommendations arising from the comprehensive geomechanical and drilling experience analyses have been implemented to improve performance during subsequent development drilling.
The field-wide geomechanical model indicates the Kilo Field is characterized by a state of stress that is transitional between a normal and strike-slip faulting regimes. The combination of relatively large differential stress and relatively weak rocks means the field is potentially subject to stress-induced wellbore instability problems. However, observations of numerous time-dependent failures imply secondary influences must also be considered to arrive at possible remediation strategies. A systematic ranking process has been developed to delineate the primary causal mechanism of wellbore instability. This process suggests that the major contributor to the time-dependent deterioration process is rising pore pressure caused by the invasion of drilling fluid into micro-fractured formations, and then exacerbated by less-than-optimal drilling practices. This finding, together with the improved geomechanical understanding of the Kilo Field, provides the basis for optimizing mud weights and wellbore trajectories as well as formulating appropriate drilling strategies to maintain the mud hydrostatic support (overbalance) in future drilling. The finding also highlights the importance of integrating geomechanics with drilling practices when developing strategies to mitigate unstable hole problems.
This paper presents a comprehensive, ordered workflow that integrates the disparate data available in a mature field to identify the most likely causative mechanisms of the time-delayed wellbore instabilities. This knowledge was then used to develop strategies for optimizing future drilling operations in the Kilo Field.