bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimizing Oil Recovery through Microbial Injection to Support the Increasing Demand for Oil in Indonesia
Authors: Budiharjo Harry , Suhascaryo Nur , Nugroho Handika Agung , Saputra Benny Ariandy 
Published: October 2017

Abstract
The method that uses microorganisms to increase oil recovery from reservoir rocks is called Microbial enhanced oil recovery (MEOR). Using this method, the microorganisms are injected to the reservoir and produce the metabolic product which is used in MEOR. There are 6 main metabolic products (bio-products) that can be effected to the reservoir fluid and rock. The 6 main bio-products are bio-surfactant, bio-polymer, bio-mass, bio-solvent, bio-gases and bio-acid. Every bio-product has a different effect on the reservoir and is produced by different microbes, with its purpose being to decrease the residual oil saturation that is left behind in the reservoir rock.
Bio-surfactant can reduce the interfacial tension between oil and the formation water and bio-polymers control the mobility of water that is used in waterflooding. Biomass can plug the reservoir pores and then change the flow direction of fluid flow in the rock. Bio-gas increases reservoir pressure and then forces the oil out of the rocks. Bio-acid can dissolve rock particles and open pore mouths, thus increasing rock porosity and permeability and allowing more fluid to flow, especially in Limestone.
A MEOR field trial was successfully applied at ‘X’ Field X in Indonesia, involves 10 wells. It can decrease oil viscosity, increase in Oil API Gravity and decrease of the oil pour point. Oil production rate increased from 8 to 66%. Scale is observed as a disadvantage of successful MEOR. The results from this field trial demonstrate that MEOR is potential and offers some benefit to increase oil production.
Planning and Execution of ERD Development Wells Project in Myanmar
Authors: Atemin Azizul , Ramasamy Kesavan , Jainuddin Mohamad Nor , Ong Chongyew 
Published: October 2017

Abstract
This paper highlights the top quartile performance well delivery of Yetagun In-fill Phase 6 drilling campaign in Yetagun gas field, offshore Myanmar. Drag, Torque, Hook load and Stand Pipe Pressure that occur in an ERD well is typically higher than conventional well due to long horizontal displacement and high lateral inclination angle. Hence, the importance of planning process, execution, drilling practices and lesson learnt which essentially resulting in a successful drilling operation were discussed in the paper.
PETRONAS Carigali Myanmar Limited (PCML) successfully drilled three in-fill wells: YA-01, YA-05, and YA-12ST1 which were classified as ERD based on extended reach industry experience plot with the objective to maintain the gas production rate. Excellent planning process and good teamwork among the project team members were required to tackle all the technical issues as well the environmental and logistical challenges. The unique and challenging design for YA-05 as compared to others where it has the longest tangent length which fall within 70-80° sail angle. YA-01 and YA-12ST1 were classified as ERD medium reach class design, thus require specific ERD drilling, hole cleaning, ECD monitoring, tripping and backreaming practices to ensure success of the well. The challenges in designing ERD wells were multiple such as high torque and drag, loss circulation, well collision, differential sticking, borehole instability, hole cleaning, longer open hole interval, high stand pipe pressure and high temperature. YA-12ST1 well was planned with sidetracking design utilizing whipstock and hence, tortuous wellpath which leads to high dogleg at the sidetrack point need to be considered. Losses of circulation were observed from historical development campaign of the field. Thus it was essential that extra precautions have been prepared for efficient hole cleaning and consistent penetration control. Other challenges attached with the recommended practices to overcome them including wellbore instability, differential sticking, drag and friction factors were analyzed further in this paper.
In conclusion, this paper serves as a reference for future ERD well planning and execution as the overall drilling campaign achieved excellent well delivery performance in term of cost and time. This campaign has been successfully completed with remarkable achievements such as the first semi-submersible tender-assisted drilling rig used by PETRONAS group, huge total cost saving, zero lost-time injury, and successfully secured the reservoir target and meet the gas volume target.
The novelty of the successful Yetagun Phase VI development wells project yielded good practices, technology used and excellent project planning that can be applied in future projects. This paper also can be a reference for future ERD well drilling in Myanmar.
Experimental Investigation on a Novel Organic-Inorganic Crosslinked Polymer Gel for Water Control in Ultra-High Temperature Reservoirs
Authors: Liu Yifei , Dai Caili , You Qing , Zou Chenwei , Gao Mingwei , Zhao Mingwei 
Published: October 2017

Abstract
This article presents a novel organic-inorganic crosslinked polymer gel, which uses resin-silicate as the organic-inorganic crosslinker, to extend the temperature limitations of currently used polymer gels for water control in mature oilfields. The gelation performances, including gelation time, gel strength and thermal stability, were studied, and the optimum composition was selected by study of gelation performances. Results show that with increase of the concentrations of components, gelation time became shorter and gel strength was improved. And the gel system was stable after 90 days at 140 °C. The optimum composition of the gel system was selected as: 4~7 wt% resin and 2~5 wt% silicate with 0.1~0.3 wt% polymer. Meanwhile, differential scanning calorimetry (DSC) measurement was used to investigate the maximum tolerated temperature of the gel. The results showed that the chemical bonds of the gel began to break at 156 °C, which indicated that the gel can resist high temperature up to 156 °C. At last, environmental scanning electron microscopy (ESEM) microstructure and fourier transform infrared spectroscopy (FTIR) spectrum of the gel were studied to analyze the gelation process and investigate the mechanism for temperature resistance. The three-dimensional network microstructure of the resin-silicate crosslinked polymer gel was more compact and more uniform than the gel prepared without silicate. The formation of silicon-oxygen bonds (Si-O) increased the crosslinking density and temperature tolerance of the gel system.
Subsea Technology - Multiphase Pumping
Authors: Anwar Zeeshan 
Published: October 2017

Abstract
Subsea gas compression and pumping technologies have been identified as a solution for accessing gas reservoirs that may be otherwise either inaccessible or economically unfeasible to drill. Subsea stations offer a fast-track development solution with flexible, multi-phase deployment, and other inherent advantages whilst filling this application. Pumping stations require a significant amount of process equipment improvements and integration solutions; however, we will focus here on the rotating machinery, process pumps in specific. In the present research, all available operator or manufacturer's reports and published papers are reviewed and a criterion is developed for subsea pump selection base on:
The conventional subsea separation system is compared to a multi-phase pumping one. All applicable types of subsea pumps including Helico-Axial (HAP), Twin Screw Pump (TSP) and Electrical Submersible Pump (ESP) are compared. All parameters in pump type selection such as Gas Volume Fraction (GVF), water cut, differential pressure, head, flow rate, fluid viscosity, RPM, sand content, water depth, Opex, Capex, reliability and asset life is discussed. Material selection as a critical part of the pump selection is studied thoroughly.
Cutting Edge Completion Design for KNUUD: Pioneering HPHT Field Development in Malaysia
Authors: Bakar Mohd Farris , Miguel Rosato , Fadzliana Azmi , Sofian Anas M. 
Published: October 2017

Abstract
KNUUD was the first High Pressure and High Temperature (HPHT) field development well embarked by PETRONAS and first in Malaysia. Learning from experience of HPHT operators in the North Sea,a detailed focus on life cycle well integrity aspect has been thoroughly emphasized throughout the well delivery phase. Initial requirement for heavy brine (16.5 ppg), which led to heavy wall production casing and high probability of tubing leak where the worst case scenarios studied in deep detail.
An extreme underbalance completion philosophy was implemented for the first time in PETRONAS. Complex processes of identifying cost effective solutions for HPHT safety critical equipment, covering the initial scoping, completing, perforating and well testing, sourcing, preparation, quality assurance and installation was systematically followed. An in-depth investigation and philosophy of managing annulus pressure build-up were also performed as part of the lifecycle integrity assurance process.
Various validation works were successfully carried out to assure the identified solutions such as V1validation (API 14L/ISO 16070) for Flow Control Equipment (4.75" Tubing Hanger Plugand 4.313", 4.188" & 4.000" Top No Go Landing Nipple's Plug), ISO 13679 CAL-IV teston completion tubing connection, API validation (API RP 19B Section IV Perforation Testing) for 2-7/8" HMX charges with maximum 6,000 psi underbalanced approach.
The well was successfully installed while recording the following significant implementation milestones for operations in Malaysia; Underbalance completion approach with freshwater instead of heavy brine (6,000 psi UB).Implementation of Vam 21 connection for 5 ½" production tubing according to ISO 13679, Connection Application Level: IV (CAL-IV).Implementation of V1 rated 15,000 psi Flow Control Equipment according to API 14L/ ISO 16070.Implementation of 15,000 psi Coiled Tubing Conveyed Perforation with deployment system& wireless depth correlation system.Implementation of annulus pressure builds up (APB) passive management with nitrogen cushion.
The comprehensive thought process and extensive efforts put in the planning stage have opened doors for significant value creation for the well delivery process. Early engagement with service providers and unique contracting approach have enabled sufficient due diligence for competitive technical solutions as well as to bring in necessary expertise to the region.
The well was successfully delivered to meet all of its objectives, producing from layers close to 16,000ft beneath the seabed. The complex process, obstacles and experiences in overcoming the challenges have indeed pioneered a confident path for future application of its kind within Malaysia and Asia Pacific region.
Imaging of Oil/Water Migration in Tightsand with Nuclear Magnetic Resonance and Microscope during Dynamic Surfactant Imbibition
Authors: Sun Yongpeng , Dai Caili , Fang Yanchao , Sun Xin , You Qing , Wu Yining , Zhao Mingwei , Zhao Guang 
Published: October 2017

Abstract
Tightoil poses huge reservoir in many countries. Due to the poor reservoir properties, such as nanometer to micrometer pores, low permeability, energy deficiency, the oil recovery in tightoil reservoir is very low, even with horizontal drilling and hydraulic fracturing. The small pores are featuring large capillary pressure thus spontaneous imbibition. Surfactant would accelerate this process. However, due to the small amount of oil in core, the accurate recording of oil recovery is challenging, especially during dynamic imbibition within fracture matrix system. Nuclear Magnetic Resonance (NMR) T2 spectra was used to characterized the migration of oil and water in pores and throats during dynamic imbibition. Various phenomenons are revealed and proved by T2 spectra figure, such as: water imbibed into small pores, oil expelled from large pores, and oil film formed on fracture face. The oil recovery during dynamic imbibition was examined online during experiment from the peak area generated by T2 spectra. Before and after the dynamic imbibition, Magnetic Resonance Imaging (MRI) was used to compare the saturation and distribution of oil in the core sample. When the oil drop migrates out of the pores, it will emerge from the surface of rock sample. Its shape on top, lateral, and bottom of the sample was observed with a long distance microscope. Their growth in width and height was compared carefully. The growth rate was categorized into different stages, and quantitatively compared.
Geomechanical Study at An Onshore Central Sumatra Field: The Investigation of Casing Restriction and Deformation in Shallow Sand Formation
Authors: Tjengdrawira Marius Agustuhong , Khaksar Abbas , Ong See Hong , Sjari'at Raihan Intan , Suhadi Annur 
Published: October 2017

Abstract
Casing restriction was encountered during workovers in 10 wells in a field onshore Central Sumatra, Indonesia. The field is operated by BOB PT Bumi Siak Pusako – Pertamina Hulu. The problem was encountered in a shallow thin sand in the depleted mature field.
A geomechanical study was conducted to determine whether the casing restriction/deformation was from excessive loading, which may have been caused by reservoir deformation and/or shearing because of fault slippages. Geomechanical factors that can contribute to casing loading and shearing include sand failure leading to cavity formation and the loss of casing support in the production interval, reservoir deformation/compaction, faulting from pore pressure changes (depletion or injection) and the corresponding stress changes.
A field-specific geomechanical model was constructed using data acquired in four offset wells drilled in the field to quantify the stresses on the reservoir rock and the existing fault(s) under depletion and subsequent water injection. The model was used in failure analyses to determine whether the stresses were sufficient to cause rock failures and fault slippage that could potentially have deformed the casings.
The study highlights the value of geomechanics as a tool in the petroleum industry for solving production issues in mature fields. Understanding the risk of rock failure because of pore pressure and stress changes enables optimization of well placement, completion design, production parameters and reservoir management to maximize recovery of mature fields.
Design of Experimental Test Method to Investigate the Effect of OBM Contamination on PVT Samples from Gas Condensate Reservoirs
Authors: Bon J. , Bon P. J. , Ortega A. J. , Nalepa W. , Koo R. 
Published: October 2017

Abstract
PVT samples captured by openhole formation testers in wells drilled with Oil Based Mud (OBM) will often suffer some degree of measurable contamination1-5. The contamination is even further pronounced for gas condensate reservoir fluid systems. Often many years will pass before production or the opportunity to re-sample the reservoir fluid and these contaminated samples are all there is to work with until that time. Improved understanding of the effect that OBM will have on these fluids will lead to improved characterization of the native reservoir fluid.
The primary objective of this work was to design a new experimental laboratory method to contaminate a clean reservoir fluid PVT sample with OBM and capture the live single-phase fluid again under dynamic conditions.
This experimental set-up will enable a laboratory to prepare samples representing PVT samples captured by Wireline Formation Testers (WFT) from an OBM drilled well, as well as the clean reservoir fluid to work with for comparison. It is envisaged that such an experimental setup will be able to be used to generate data to then study the effect of OBM contamination of PVT samples and ultimately improve the ability to correct PVT data on contaminated samples to obtain representative PVT properties.
In order to test the experimental test method, base oil from an OBM was used to contaminate a gas condensate PVT sample with Condensate Gas Ratio (CGR) of 25 stb/MMscf. The data obtained from results from both contaminated and uncontaminated sub-samples were then used to investigate the effect of OBM on PVT properties.
Sufficient sample was obtained in order to measure dew point, Z-factor, CGR and composition of the resulting contaminated samples to compare to the same properties from the original uncontaminated reservoir fluid sample.
In this paper we present the following: A new experimental set-up was designed to create contaminated PVT samples from a clean sample under dynamic conditions – flowing within a porous media at reservoir conditions.With the experimental set-up we were able to obtain samples and data for comparison of a clean and OBM contaminated sampleResults indicate that under the right conditions, a condensing-vaporising partial miscibility dynamic is established between the gas condensate reservoir fluid and base oil.
Unique & Practical Approach in Selection and Classification of Hydrocyclone Desander Technology: Utilizing a Decade of Experience
Authors: Gupta A. , Kamat D. , Shahrum Z. , Firmansyah A. , Salleh N. I. , Tan B. C. , Madon B. 
Published: October 2017

Abstract
With the advent of advancement in hydrocyclones in oil industry, there has been various types of hydrocyclone based desanding system developed each with its own pros and cons. Main challenges being the handling of multiphase fluid resulting in four phases of feed and challenges in designing. Operators had been facing various challenges in sand management since a decade which has resulted in installation of various hydrocyclone based desanders. Many of the hydrocyclone based desanders did not perform as per expectation and mixed results were observed. With more sand handling issues expected in future, a study was conducted to ascertain lessons learnt and challenges in past installations and way forward for future.
A focussed team which includes production technologists and process specialists was established. The team compiled the installation histories of earlier installations and challenges. These included design, operational and logistic details for any installation. Approximately 15 different desander technologies currently prevalent in market and within the region were evaluated to understand the mechanism and variety of each type.
The cyclone system was categorized into fixed, changeable with insert and dynamic cyclonic desander for ease of evaluation. The learnings from the earlier installations indicated significance of category which needs to be considered for an installation. Parameters like pressure drop across the cyclone, inlet pressure at the cyclone system, particle size separation, gas volume fraction at the feed volume of sand being produced, sand handling capability of the facility etc. turned out as significant contributors for selection of desanders. Operator's conditions of high gas volumes, relatively finer particles being produced and low pressure environment turned out to be biggest technical challenges in selection of a proper desander. Other challenges included importance of a multi-disciplinary team, contracting strategy and type of desander to be deployed. It was apparent from the study that any future installation would require more systematic approach rather than "pick up from shelf" approach on the desanders.
A unique selection flowchart was established as a guideline for selection of hydrocyclone desanders on the basis of major parameters to decide not only on the type of desander required but also the location of desander in a facility. The new by defined category eased out this entire process. To avoid any failure for future selection and installation, a well-defined contracting strategy was established to encompass various types of desanders easing the selection process and utilizing the study results. This entire effort resulted in huge potential value creation and promised a significant saving in man hours.
Solids Production Prediction and Management in a High Porosity Carbonate Reservoir - A Case Study from Offshore Vietnam
Authors: Asadi M. S. , Khaksar A. , Nguyen H. Q. , Manapov T. F. 
Published: October 2017

Abstract
Carbonate reservoirs hold 50 to 60% of the world's conventional hydrocarbons and are therefore of major economic significance. Solids production from poorly consolidated carbonate reservoir rocks is a common factor in many wells during production stages and especially in the later life of a reservoir under depletion conditions. While there are several well-estblished technuues to predict sand production in sandstone reservoirs, there are not many field-proven case studies on the applicability of these techniques for solids production assessment in carbonate rocks. In this study, we present a case study on the application of a widely-used sanding evaluation technique in a carbonate gas reservoir, offshore Vietnam.
We show production, core and well data from several production and appraisal wells in three nearby gas fields to investigate the cause of well productivity reduction in one well through a systematic geomechanical assessment of solids production. The findings are used to optimize gas production in existing wells, determine maximum solids-free drawdown for a planned infill well, and completion decisions for two new development wells to be drilled and completed in 2018 in a field with no production to date.
Rock mechanics tests conducted on several carbonate samples confirmed the low strength and high heterogeneity nature of the reservoir carbonates. Core-log calibration of rock mechanics paramters revealed reasonably strong correlations between rock strength and porosity logs which were used to generate continuous log-derrived rock strength profiles. Applicability of a well-established poro-elastic sanding predction model for carbonate reservoirs was investigated by a logical solids production analysis in a cased and perforated explorationwell and two open hole production wells. Production, well testsand fluid sampling data were used to calibrate and verify the solids production model.
Analysis showed no risks of solids production for the weakest reservoirs at initial and current reservoir pressures with the current applied drawdowns, and the drawdown can indeed increase in exsiting wells by another ~200 psi without the risk of solids production. The results however indicated that as the reservoir pressure reduces the solids-free drawdowndecreases rapidly and will approache zero when the reservoir pressure dropsby another600-800 psi. Therefore, solids control measures are essential to prevent solids production at later life of the field.
The results of the study and historical knowledge of the field reservoir and production were used for completion design of two vertical infill wells with the aim of increasing production from one of the major gas-producing blocks for Vietnam's domestic gas supply. The infill vertical wells will be completed open hole with external gravel pack and screen as the solids control measures.