bluuebunny/crossref_metadata_2025 huggingface dataset:
Worm-Like Micelles as a Mobility Control Agent for Chemical Enhanced Oil Recovery
Authors: Kumar S. , Awang Mariyamni , Ahmed Shuaib , Dehraj Naeem Ul. , Saleem Yasir Sheikh
Published: October 2015

In this Paper, Wormlike Micellar (WLM) solutions were studied as an alternative to polymeric mobility control agent in chemical enhanced oil recovery. In which, two compositions of WLM solutions were chosen and prepared in laboratory – Hexadecyltrimethylammonium Bromide/Sodium Nitrate and Three-(N, N-Dimethyloctadecylammonio) Propane-Sulfonate/Sodium Dodecyl Sulfate (TDPS)/Sodium Chloride. Then following experiments were conducted – thermal stability test, rheological measurements to account the effects of concentration, shears rates, salinity (NaCl = 3.5% w/v, CaCl2 = 0.05% w/v and MgCl2 = 0.05% w/v), and temperature (30 to 70 0C) on viscosity of these WLM solutions. Another stability test was conducted to test the effect of crude oil on WLM solution.

The results showed that WLM solutions have excellent rheological resemblances with HPAM polymer solutions. On addition of salts, the WLM solutions were highly tolerant over entire range of shear rates. At 70 0C, the thermal degradability of WLM solutions was less than HPAM polymer. Despite of all these significances viscosity of WLM solutions was deemed to the viscosity of water (1 cP) on mixing crude oil. It was due to strong interfacial activity between surfactants present in WLM compositions and crude oil. Such as, the IFT between crude oil and WLM solution was observed very low (0.3 to 0.55 mN/m) as compared to the typical system of water-oil (20 to 50 mN/m). Besides, core flooding was performed by mixed surfactant WLM solution (TDPS = 1.09% w/v, R = 0.55) at 70 0C.

The WLM solution produced an additional oil recovery of 10.9% beyond secondary recovery. Thus the results supported WLM solution to be potential mobility control for chemical EOR.
Integrated management and Application of Horizontal Well Water Flooding Technology in a Large-scale Complicated Carbonate Oilfield Containing High permeability Streaks
Authors: Dandan Hu , Rui Guo , Songhao Hu , Yuanbing Wu , Zhaowu Zhang
Published: October 2015

AD oilfield in Iraq is a large-scale complicated carbonate oilfield with mid-high porosity and low permeability, of which OOIP is 3.5 billion barrel. The lithology and property for the oilfield is featured with strong heterogeneity, especially high permeability streaks and dissolution existed partially. In Middle East fewer examples are successful in application of horizontal well water flooding technology for the similar oilfields. Integrated management is the fundamental for the application of horizontal well water flooding technology.

The paper put forward an integrated management system of horizontal well water flooding technology for the complicated carbonate oilfield. Water breakthrough mechanism and injection timing for horizontal water injection are studied based on numerical simulation, pilots and laboratory experiments. Production management system has been established to evaluate productivity, analyze production law for ESP producers and the change for reservoir pressure, which also timely diagnosis abnormal condition for producers and injectors. Evaluation and optimisation system are put forward including multiple indexes evaluation model for horizontal well water flooding's development effect, classification charts for horizontal well with different changing law, cause analysis for abnormal water cut increasing, and optimization for pressure and production/injection parameters. The relevant optimization and adjustment measures have been recommended and implemented in time to maximize single well production through the integrated system.

The production capacity has been constructed up to 7 million ton per year and achieved stable yield of 3 years continuously in AD oilfield, of which 6% was increased by horizontal well water flooding. The ultimate recovery factor of horizontal well water flooding has been predicted about 40%, nearly 2% higher than that of the overall field development plan in 2011. The integrated management of horizontal well water flooding technology will provide significant technical support for longer stable production with 70 million ton per year in AD oilfield. The application result has significant reference for the development of complicated carbonate reservoirs containing high permeability streaks in Middle East.
A New Advance in Window Exit Milling Using Aluminum Casing
Authors: Butler Ben , Benson Cole , Steele David , Sherston Mitchell , Metz Stephen , Lehner Jeffry
Published: October 2015

Two methods are commonly used to produce window exits in multilateral wells. One implements premilled window technology, while the other involves steel casing milling. Steel casing milling generates steel cuttings that can be challenging to circulate to surface during wellbore cleanout and can hinder equipment in subsequent downhole operations. Premilled windows eliminate steel debris; however, they require that the main bore casing string be oriented. This paper describes an additional approach that does not create steel milling debris nor requires orientation of the casing string, which can result in significant time savings and risk reduction.

This approach involves an all-aluminum casing exit joint (hereon referred to as ACE joint) coupled to a lower coupling with a latch profile in which service tools can be landed to perform junction construction. This new technology, including design rationale, development, installation procedures, subsequent testing, and field trial results are discussed within this document. The ACE joint was designed, manufactured, and deployed in a multiwell, TAML 5 multilateral field development containing bilateral and trilateral wells. To create the window exit, the ACE joint and latch coupling are made up to the main bore production casing and cemented in hole. An orientation tool is then run in hole (RIH) and latched into the joint latch coupling, obtaining coupling orientation. The whipstock and mill assembly is then configured at surface to the desired millout orientation, RIH, and latched into the ACE joint for subsequent milling operations.

Lab testing has been performed to qualify the ACE joint for suitable milling performance, corrosion resistance, and drilling wear resistance; all with positive results. Field installations have also been successful, with bi and trilateral wells having laterals exceeding 2000 m in length being created without problem. The tests and field installations demonstrate the ACE joint is now a proven technology, confirming the window geometry post millout to be acceptable for lateral drilling and completion operations.

This new approach to window millout technology represents an improvement to existing steel casing milling technology, providing a more suitable solution for removal of milling debris and a more simple installation process.
Reducing Risk and Improving Efficiency of Extended Reach Drilling Through Use of Sampling While Drilling Technology
Authors: Lean Jonathan , Ying Tan Chi , Fey Scott , Pop Julian , Indo Kentaro , Varughese Jimmy , Megat Amanda , Liu Chun Lin
Published: October 2015

Extended reach wells are drilled to access large areas of reservoir from a relatively small surface footprint. As a secondary zone becomes a target, other zones in the openhole drilled section may have already been subject to pressure depletion. These two challenges significantly increase the risk of conducting comprehensive formation evaluation.

Logging-While-Drilling (LWD) technologies have evolved over the last 25 years to provide much of the required formation evaluation data. In situations where conveying wireline tools would be difficult, LWD tools are incorporated into the drillstring and provide formation evaluation data. They also have much higher ratings for tension and compression and, coupled with the ability to rotate, reduce the risk of differential sticking. A key LWD technology developed recently is formation sampling while drilling (FSWD). FSWD is an evolution of formation-pressure-while-drilling (FPWD) tools that, in addition to making formation pressure measurements, can also capture and analyze samples ofdownhole fluid in the same manner as current wireline formation testers.

This paper recounts an FSWD operation conducted offshore Malaysia. The primary sampling objective was to collect representative in-situ samples of gas and water, which were not previously captured in this reservoir. Of key importance was the quality of the water samples in order to accurately measure salinity, refine water saturation calculations, and provide assays for corrosion considerations related to completion design and production planning.

Previously, a time-consuming operation—using a wireline formation tester conveyed on drillpipe—would have been the only way to capture quality downhole samples, but a major concern was differential sticking, caused by a highly deviated wellbore, that would potentially intersect depleted zones. As an alternative, the FSWD tool was deployed to measure formation pressures (used to infer large-scale reservoir connectivity) and to collect gas and water samples, all in a single drilling run.

Results demonstrated that in high-risk wellbores, FSWD tools could capture high-quality downhole fluid samples. Also, the real-time data transmitted using mud pulse telemetry was sufficient to identify fluid type during the pumpout, and tool controllability enabled fluid sampling in single-phase condition. Using FWSD tools eliminated unproductive time associated with a dedicated drillpipe conveyed wireline run, along with the associated additional openhole exposure time that could have jeopardized the success of the completion. The samples acquired with the FSWD tool were of a quality high enough that the operator was able to cancel wireline sampling operations planned for two additional wells, further saving time and reducing risk.
Drill String Torque Reducing Technology Improves Drilling Efficiency in Horizontal Well
Authors: Yim M. , Healey S. , Leedham R. , Giuliano M. , Weber M. , Pitre D.
Published: October 2015

Horizontal wells have proven highly beneficial to the Oil and Gas Industry by enabling operators to tap into reservoirs previously deemed inaccessible by conventional drilling practices. This inaccessibility was particularly evident when drilling unconventional reservoirs; the efficient penetration and successful production of oil and gas from low permeability formations was economically impossible. While horizontal wells provide many benefits, there are several limiting factors challenging the industry as it pushes for longer ERD wells. Drill string torque capacity and top drive torque capabilities are two of the most common limiting factors.

In 2012, Beach Energy Limited encountered challenges drilling the 8 ½″ horizontal section of an Australian gas well (Well-A). The main challenge faced was the well profile's significant surface torque, as a result of side forces exceeding 2,000lbs. These factors led to damaged equipment, compromised wellbore quality and drilling inefficiency.

To improve drilling efficiency, Beach Energy Limited utilizes torque reducing subs in the horizontal section of the subsequent well (Well-B). The 8 ½″ horizontal section of Well-B was drilled over three times faster than offset Well-A by effectively reducing surface torque by an average of 23%. This section was successfully drilled utilizing torque reduction subs to protect the drill string from the high side forces in open hole; prevent drill pipe tool joints from contacting the wellbore, thus enhancing the drilling response and reducing surface torque; and improve BHA stability yielding better wellbore quality. The end result of the project was a longer horizontal wellbore placed in the payzone with significant rig time savings.
New Generation Cutters Boost Hybrid Bit Performance in Volcanic Basement in Northeast China
Authors: Wan Jun , Lan Zhongxiao , Guo Hongyan , Gao Chunliang , Sheng Simiao , Valbuena Franklin , Zeng Jun
Published: October 2015

Development blocks around Daqing, P.R. China are challenging directional drilling applications. Xushen comprises the largest volcanic gas reservoir in the Ying Cheng formation among 5 development blocks. The formations are hard and abrasive and include a volcanic basement of rhyolite, tuff and breccia with unconfined compressive strength (UCS) up to 30 kpsi.

Polycrystalline Diamond Compact (PDC) bits experience high vibrations and premature wear and bit ring-outs. Overall, PDC performance results in short footage and very low rates of penetration (ROP). For a decade, heavy-set roller cones, IADC 617 to 637, were believed to be the correct alternative to drill this hard, heterogeneous formation. However, roller-cone bits are slower than PDC bits and have a limited bearing life. A detailed engineering analysis was undertaken to increase both the penetration rate and distance drilled.

As a result of this study, a hybrid bit which combines the advantages of a fixed-cutter and roller-cone was employed to drill in this application. The PDC portion of the hybrid bit design also included a new cutter edge geometry to reduce spalling and impact damage observed on historical PDC runs. The first run in the Ying Cheng group increased ROP by a record 115%, with nearly two times the distance drilled compared to roller-cone bits in the same section. This revolutionary new bit and cutter technology improved reliability and increased drilling efficiency for the duration of the project. After the introduction of this new hybrid bit to the drilling campaign, the operator performed 16 bit runs and saved multiple runs per section.

This paper presents a case study of the hybrid bit runs in both the directional and horizontal sections on the wells in northeast China. The detailed analysis of the drilling data also presents the economic benefits of the project and the potential impact of the new technology for the industry.
An Efficient and Parallel Scalable Geomechanics Simulator for Reservoir Simulation
Authors: Luo Jia , Chen Zhangxin , Wang Kun , Deng Hui , Liu Hui
Published: October 2015

A tetrahedron-grid based parallel geomechanics simulator is developed and presented in this paper. Parallel computing is employed to handle large scale problems by benefiting from its features of distributed memory storage and efficient runtime reduction. This simulator aims to describe rock matrix deformation and its interactions with pore fluid. In the consideration of the feasibility in coupling with a variety of existing reservoir simulators, the modularized geomechanics simulator is designed to be a library. Through interfaces provided by the library, conventional reservoir simulators can get geomechanics effects involved.

In this paper, the framework of a parallel geomechanics simulator and the strategy for coupling with a reservoir simulator are presented. Iteratively coupling approach is employed to make geomechanics modeling more independent and flexible. The procedure for solving solid mechanism and calculating coupling parameters is general, which can be applied to more complicated constitutive laws and rock property descriptions. A parallel strategy is proposed to improve the computational efficiency of solving the coupled problem. To verify the utility and efficiency of the geomechanics simulator, simulations coupled with a three-phase black oil model are performed. Expected geomechanical phenomena are illustrated by numerical experiments. In addition, for testing the scalability behaviour, field scale problems with millions reservoir and geomechanics grid blocks are performed. We use an increasing number of processors to run the cases, respectively, and the results indicate an encouraging speedup.
Development of Discontinuous Galerkin Methods and a Parallel Simulator for Reservoir Simulation
Authors: Wang Kun , Zhang Linbo , Chen Zhangxin
Published: October 2015

The classical discontinuous Galerkin (DG) methods are designed for elliptic (parabolic) problems and hyperbolic problems. For reservoir simulations, the pressure equation from the black oil model is elliptic (parabolic), while the equations for saturations are hyperbolic. Due to this special property, it is difficult to directly apply the discontinuous Galerkin methods to the black oil model. In this paper, we extend the discontinuous Galerkin methods to reservoir simulations. In our schemes, the local discontinuous Galerkin (LDG) method is used to discretize the black oil model. The upwind concept is combined with the numerical flux term of the LDG method to simulate the direction of propagation of the multiphase flow in reservoirs to avoid the unphysical solutions. We also extend the Peaceman model to the discontinuous Galerkin methods on unstructured grids. Based on the extended discontinuous Galerkin methods, we employ the iterative implicit pressure-explicit saturation (iterative-IMPES) and fully implicit (FIM) methods to solve the coupled nonlinear black oil model. A parallel simulator is implemented using the parallel adaptive finite element package, Parallel Hierarchical Grid (PHG), and validated by testing the first and ninth SPE Comparative Solution Projects. The parallel scalability of our simulator is also tested by a large scale case.
Two Dimentional NMR Analysis and Evaluation of Oil or Gas Shale
Authors: Wang Zhizhan , Qin Liming , Lu Huangsheng , Li Xin , Du Huanfu , Gai Shanshan , Niu Qiang , Yang Peiqiang
Published: October 2015

Oil or gas shale is characterized by Nano-scale porosity, self-source-reservoir and complex lithology. Both Conventional NMR analysis method and petro-physical model are not suitable for this formation evaluation. So, based on increasing investigation resolution of the Nano-scale pores and signal to noise ratio, the field frequency is added from the 2~5MHz to 11MHz and TE is decreased from 0.6ms to 0.06ms. Therefore, the pore scale resolution in T2 spectrum is improved from 0.1ms to 0.01ms in order to satisfy for the oil shale exploration. In addition, the petro physical model of oil shale is established to distinguish the organic pore, inorganic pore and micro fracture. Through this method, the reservoir quality can be evaluated, such as physical property, hydrocarbon generation, and pore pressure to provide the effect support for the reservoir fracture, plan design and fracture assessment.
A New Mechanistic Model for Predicting Dynamic Corrosion-Erosion in Gas Production Pipeline under the Influence of FeS Scale
Authors: Santoso R. K. , Fauzi I. , Rahmawati S. D.
Published: October 2015

This paper presents a study about corrosion-erosion phenomenon in natural gas production pipeline when FeS scale is formed on the inner surface of the pipeline. FeS scale is chosen here because its reaction is faster and more reactive than the other scale such as FeCO3.

A literature study was firstly conducted to develop the idea of corrosion-erosion model. Several phenomena were considered to be the best to describe corrosion-erosion process. Then, the mathematical model to calculate corrosion-erosion rate was derived. The corrosion-erosion process was divided into two steps: fluid flow and heat transfer phenomena to establish corrosion-erosion environment and diffusion phenomena to make the corrosion-erosion happened. The first phenomena were modeled using Thermodynamics equation with considering Joule Thomson effect and gas flow equation (Katz for vertical-inclined tubing and Panhandle-B for horizontal pipeline). The second phenomena consisted of mass transfer equations including erosion process to evaluate scale growth. Finally, the model was applied to calculate an example case of gas well. The result was then compared with several simulators' result.

Pressure profile, temperature profile, liquid distribution, scale formation rate and erosion rate are generated as the first phenomena simulation and become the basis to evaluate the corrosion-erosion rate value. The simulation of second phenomena will provide the value of corrosion-erosion rate for each segment in production pipeline. Corrosion is mainly caused by the reaction of iron in pipe and corrosive agents in produced fluid such as CO2 and H2S. Supporting by erosion process, corrosion will badly damage the pipeline. Moreover, the simulation's result shows that at early time, corrosion and erosion simultaneously occurs because of the absence of FeS scale. However, at time t, when the FeS scale has been formed, the corrosion rate is reduced. If the erosion rate is larger than the scale formation rate, corrosion and erosion will conjunctly occur as at the early time. In addition, the difference in model and simulators' result is primarily caused by the effect of considering the scale growth process.

Corrosion and erosion are critical problems which need to be early prevented. An accurate prediction determines the effective prevention action. This paper gives a more accurate prediction by considering Joule Thompson effect and scale formation process. A segmented corrosion-erosion rate as the result of this paper can be considered to choose an effective action.
Tie Back Liner Mechanism Application at North Senoro Drilling Gas Field Development Project
Authors: Widyatmoko Antya Bagus , Rahmadona Desmawati
Published: October 2015

North Senoro Gas Field is located onshore, operated by JOB PERTAMINA – Medco E&P Tomori Sulawesi. The aim of North Senoro Development is to produce gas from limestone reservoir (Mentawa reef), member of Minahaki formation to fulfill gas supply commitment to Donggi Senoro LNG Plant. This field was discovered by Well A wildcat well in April 1999. Afterward, five successful delineation wells have been drilled and tested in year 2001, 2003, 2005, 2007, and 2009 named Well B, Well C, Well D, Well E, and Well F. Those wells used 7" liner carbon steel material.

Fluid analysis shows existence of H2S up to 0.06 Mol %, CO2 up to 2.16 Mol % in gas stream and Cl− content in produced water up to 15,531 mg/L. Reservoir pressure is 2900 psi and temperature is 2120 F.

Based on North Senoro reservoir fluid characteristic which have H2S and CO2 content, best recompletion method should be chosen to convert old exploration wells into production wells with good performance and cost effectiveness.

Well known recompletion methods are Monobore and Side Track. Recompletion methods using Tie Back Liner Mechanism was an alternative solution utilize in this project to convert 3 existing/exploration wells into production wells with good performance and cost effectiveness.

Recompletion method using tie back liner mechanism was successfully installed in 3 wells. Those wells had been produced since December 2014 to supply Donggi Senoro LNG Plant.
An Improved Numerical Simulator for Surfactant/Polymer Flooding
Authors: Yang Jing , Jin Baoguang , Jiang Liangliang , Liu Fang
Published: October 2015

Due to the high demand to increase oil production combined with the huge potential in enhancing oil recovery, surfactant/polymer (S/P) flooding is under increasing interest and importance in recent years. Numerous studies have shown that interactions between surfactant and polymer can be extremely important to the final displacement performance of S/P flooding, since the desired effect of polymer and surfactant may be enhanced or degraded as various slugs become mixed underground. Nevertheless, as far as we know none of the available commercial numerical simulators can account for the impact of these interactions.

The study focuses on constructing an improved S/P numerical simulator. A series of experiments were performed on S/P mixed system and flooding process. The results show significant influence of S/P interactions on viscosity, interfacial tension, and adsorption, and the interactions can be totally different when injected into different S/P systems. Quantitative relationships of the interactions were then provided based on the results. Then, an S/P flooding mathematical model was established on the basis of mass conservation, with the description of various important phenomena during flooding process being included, especially for the interactions between surfactant and polymer. Adaptive implicit method was applied to solve the equations and a simulator was developed. The simulator was finally used to perform the numerical study of different S/P mixed systems, in which synergistic promotion, non-interaction and competitive repulsion were respectively presented. The displacement performance was the best when synergistic promotion existed between surfactant and polymer, followed by non-interaction, and competitive repulsion. In summary, a new method for the treatment of interactions between surfactant and polymer in numerical simulation was derived in this work. The improved simulator could enhance the matching degree between mathematical model and field data.
Walker Rig and Batch Drilling System Contribution in Reducing Moving Time and Increase Drilling Operation Efficiency in North Senoro Drilling Gas Field Development Project
Authors: Panhar Muhammad Lutfi , Rahmadona Desmawati
Published: October 2015

In September 2013, North Senoro development drilling of JOB PERTAMINA – Medco E&P Tomori Sulawesi operated Senoro Field – Central Sulawesi, Indonesia commenced when the rig was rigged up over a rig base in Well B Cluster with 8 new well slots available. The well slots were the 20" conductors, piled when the project was still in site preparation phase. Drilling commenced with objectives of drilling, completing and testing 6 new directional wells and 1 re-entry wells.

The objective of the Field development was to have high gas production rates available when JOB PERTAMINA – Medco E&P Tomori central processing facility and Donggi Senoro LNG Plant was completed and started in first week of January 2015. Since all wells had to be drilled before first production, and require few weeks to connect the wells with central processing facility then all effort was addressed to optimized operation, shortening operation time and avoid any incident or accident. Walker Rig and Batch Drilling System were implemented to fulfill the entire objective and minimize costs.

The Batch Drilling System was applied based by the availability of designated well slots in Well B Cluster. These well slots position were placed based on planned operation which expected to complete 4 first wells (Batch Group 1) and do well testing while at the same time, the rig was moved to the other side of 3 remaining wells (Batch Group 2) and drill the wells. In planning this system, all risk had to be considered when performing simultaneous operation of drilling and well testing (SIMOP); including when there was well control situation since North Senoro Field is a gas field with total loss reservoir and 2,900 psi reservoir pressure.

By utilizing Walker Rig and Batch Drilling System, JOB Pertamina – Medco E&P Tomori Sulawesi has been able to save moving days from 56 days to actual 15.56 days, saving at least +/− USD 1.3M and achieve HSE performance 1,923,683 man hours without loss time.
A Semi-Analytical Model for Production Simulation of Complex Fracture Network in Unconventional Reservoirs
Authors: Jia Pin , Cheng Linsong , Huang Shijun , Cao Renyi , Xu Zhongyi
Published: October 2015

Unconventional reservoirs, such as tight oil and shale gas reservoirs have emerged as a significant source of energy supply in the world. The technologies of horizontal well drilling and hydraulic fracturing have made it possible for such reservoirs to be developed commercially. Interacting with the pre-existing natural fractures, multi-stage hydraulic fracturing along horizontal wells creates complex fracture networks. Compared with the traditional single or multiple planar fractures, the flow process in these fracture networks is significantly different due to the complex interplay of flow between the interconnected fractures. This paper presents a semi-analytical model for production simulation of complex fracture networks in which hydraulic and natural fractures can interconnect with arbitrarily angles. To model the flow behavior more rigorously, we represent fractures within the network explicitly rather than idealize them as a dual-porosity medium. In the model transient response is obtained from coupling a reservoir flow model and a fracture network flow model dynamically. Source functions in real domain and superposition principle are adopted to model the flow process in reservoir analytically; thus, the flow equation of network is solved by finite difference method numerically. Furthermore, Star-Delta transformation is introduced to solve flow redirection and flux redistribution among the interconnected fractures within network. The validation of the semi-analytical model is demonstrated in comparison to the solution of ECLIPSE simulator. Production simulation of orthogonal and un-orthogonal fracture networks are taken by use of the semi-analytical model. In addition, with a field example from the Barnett shale, we show the capacity and practical use of the model to evaluate well performance and stimulation effectiveness of complex fracture network in unconventional reservoirs.
Well-Plant Operation Model: Case Study of Tight-Gas Sands in Sulige Gas Field, NW China
Authors: Naizhen Liu , Ming Liu
Published: October 2015

Sulige gas field is a typical tight gas reservoir with the features of low-pressure, low-permeability and low-abundance. Its gas-bearing condition is bad so that the economic benefit is not good. To improve the well performance and economic benefit, an applicable well-plant operation model which includes the design optimization, the technology template, the streamline operation, the standardized regulation, the resources generalization and the integral management is established through continuous explorations and practices.

This paper describes the successful well-plant operation model conducted in block Su53 along with the pilot project in block Su11. The well-plant operation model increases the operation efficiency, shortens the drilling period and saves the cost. 8 vertical wells are drilled in the pilot project in Su11, which takes 6 days to be fractured and bring great economic benefit. In addition, the well performance is significantly improved compared with other vertical wells in the block Su11. The pilot project provides experiences for the well-plant operation model in block Su53. 13 wells which include 10 horizontal wells, 2 directional wells and 1 vertical well are drilled in a 200m×300m well pad, lining in two arrays. The target formations are H8 and S1, ranging from 3150m~3500m. The whole job including well pad construction, drilling, completion, fracturing, gas testing and production for all 13 wells is finished in only 210 days. Compared with the conventional single-well job, the well-plant operation model saves a lot of time and money. The environmental protection is enhanced. The development model of the block Su53 is very successful and the well-plant operation model receives much attention in China. The successful application of the model provides invaluable experience for the development of tight-gas sands and shales in China.
Building an In-House CMMS to Simplify Maintenance Management in an Oil and Gas Company
Authors: Handoko Bambang , Anwar Syaiful , Siswanto Hadi , Amir Mohamad Fauzan , Pribadi Rossupanji
Published: October 2015

In modern oil and gas industry, the use of a Computerized Maintenance Management System (abbr. CMMS) is an essential part to simplify maintenance management. Considering cost and time as crucial factors, there are two alternatives to obtain a CMMS: in-house development or by purchasing an off-the-shelf software package, where both choices have their own set of benefits and weaknesses. Commercially available software packages are usually offered at premium prices, but frequently, lack the ability to be customized to company requirements. Customizing software packages could cost the price of the program itself. Therefore, for companies with limited budget, such approach is a major concern. Moreover, if many of the features and functions left unused, the total waste of such investment would be greater.

This paper describes a CMMS implementation, called INTRAMAS (Integrated Asset Management) that has been developed in-house by some of the authors, empowering our own resources and assisted by internship students from a reputable university in Indonesia, i.e. the ITS. This software tool offers some major advantages, such as low-cost investment, increased high level of flexibility, higher potential for optimal training development and adaptability to current maintenance operations. However, to reach the desired objectives, some challenges must be dealt with, among others such as: paradigm shifting from manual to computer-based approach, personal reluctance due to lack of computer skills, asset register and document inputs, as well as management acceptance when the idea was arising initially.

Facilitated by standard features designed in a web-based environment, INTRAMAS offers a great extend of advantages. Reports and Key Performance Indicators (KPIs)/metrics can be generated automatically and useful for analysis, evaluation and decision-making in maintenance management. The software application run successfully and proven to meet its expectation. The success story encouraged SKK Migas (Special Task Force for Upstream Oil and Gas Business Activities Republic of Indonesia) to organize a workshop facilitating the knowledge sharing between Lapindo Brantas Inc. (as source reference) and other Production Sharing Contract (PSC) companies, particularly of which are yet to apply this technology. It is expected that the successful experience will endorse the companies to follow the similar approach in developing CMMS in-house, which will result in the saving of cost recovery made by the government.
High Expansion Technology Opens the Way for Enhanced Recovery
Authors: Robinson Larry Grant , Gray David , Bill Bjorn
Published: October 2015

The objective of this paper is to examine the recent improvements in packer and plug design, minimizing packer element extrusion. Based on these changes, operators now have more intervention options at reduced risk. While applicable to both new completions and interventions, this paper will focus on intervention technology.

For many years, extrusion gap has been controlled primarily by the use of a "Gauge Ring" as a packer back up. While successful, this approach dictates a large OD packer or plug to minimize extrusion gap. As our industry has developed more tortuous well bore geometry, large ODs have led to running and pulling problems. These designs have also prevented many operators from recovering failed zones. Water encroachment, gas migration and failed sand screens have often been dealt with by re-completion. Options were limited to inflatable systems, long elastomer or umbrella types of plugs. Horizontal completions further reduced that to only inflatable solutions, due to umbrella systems dependency on cement. Recent developments in high expansion products have opened up new opportunities to recover from these types of problems.

High expansion elastomers and new design packer back-up systems allow for actual V-Rated packer, plug and straddle systems. With this benefit, comes the added value of a retrievable system. Intervention work always carries with it the risk of failure. Recovery from a failed intervention can sometimes be a return to the original work-over plan. The most successful of the new systems incorporate expanding packer back-ups. High expansion types of systems are now being used for:

Horizontal sand control in failed screens Packer failure recovery Straddles, straddles with stand-alone screens Zonal isolations, (including straddles) P&A work

This type of equipment allows for the recovery of a failed intervention, as well as recovery from a change in wellbore dynamics. If the intervention team set the high expansion style system in the wrong place, they simply recover that and re-run at the correct depth. Should wellbore changes dictate a change, all or part of that system can be recovered and modified to accommodate the change in pressure/gas/water/sand.

In conclusion, the ability to reduce extrusion gap, while at the same time reducing OD of completion / re-completion components, brings operators new avenues of success with reduced risk. Exciting new applications include, high expansion style straddles with sliding sleeves, Smart valves, and chemical injection systems.
The Effectiveness of Development Methods in the Apprenticeship Program
Authors: Widodo Untung Hendy
Published: October 2015

This paper aimed to evaluate the effectiveness of Apprenticeship Program implemented by ConocoPhillips Indonesia. The scope of this study is fresh graduate hires in the selection year 2010-2012. This study used a qualitative research methodology by developing strategies based on the Three Gears of Development developed by the Corporate Leadership Council (CLC) and the method refers to the Kirkpatrick's evaluation model. From the analysis performed it was concluded that the Apprenticeship Program has brought business impact, the most useful method of development is experiencing in which there are on the job training and project assignments embedded in meaningful assignment, as well as the relationship and feedback through coaching and mentoring.
The Impact of Nanoparticles Adsorption and Transport on Wettability Alteration of Water Wet Berea Sandstone
Authors: Li Shidong , Torsæter Ole
Published: October 2015

Wettability alteration was proposed as one of the main Enhanced Oil Recovery (EOR) mechanisms for nanoparticle fluid (nanofluid). A series of wettability index measurement experiments were conducted for water wet core plugs, which were treated by nanofluids with varied nanoparticles concentrations and types of nanoparticles. Nanoparticles transport experiments with the same nanofluids also were performed to study nanoparticles adsorption behavior. Effluent nanoparticles concentration was measured to evaluate nanoparticles adsorption and desorption inside core. Pressure drop was recorded during nanoparticles transport process to show effect of adsorption on permeability. Wettability index measurements were also performed for hydrophobic nanoparticles to investigate its effect on wettability.

The results of wettability alteration experiments indicated that hydrophilic nanoparticles have ability to make the core more water wet but not significantly. Hydrophobic nanoparticles can delay spontaneous imbibition while cannot change original wettability. For nanoparticles transport experiments, the results showed that the nanoparticles undergo both adsorption and desorption during injection. Effluent nanoparticles concentration curves were plotted to find breakthrough time. Experiments with varying concentration and type of nanoparticles showed different adsorption and desorption ability for water wet core. Permeability impairment was observed during nanoparticles dispersion injection.

This experimental study combined the effect of adsorption and transport of nanoparticles inside Berea sandstone on wettability alteration and permeability impairment. The objective of this paper is to release the influence of nanoparticles adsorption and transport on EOR of nanofluid.
Acquisition Pressure and Temperature Data without Slickline Unit
Authors: Hadi Saeful , Orryandhi Caksananda
Published: October 2015

Limau Field is the part of PT Pertamina EP Asset 2 that having many well intervention jobs especially reopening & work over in each years. Lack of reservoir data has been found because since in generally these wells are old well. Reservoir data (Pressure & Temperature) needed for evaluating well productivity as well as basic information to choose type of artificial lift if the well have good oil reserve.

Acquisition data carried when swab job for updating the data reservoirs. It requires Electric Memory Recorder (EMR) and Slickline unit as conveyor. Lack of Slickline unit is a problem to get the data if two or more well intervention jobs done in the same time.

This tool has been modified since 2 years ago so when the job is done in the same time, then it will receive the data at the same time. The measurement EMR by using slickline tool or IBC tool at the same well and same time is the way to find out the accuracy of the data. The results are no differences data between slickline and IBC, so to IBC could replace data using slickline units.

This paper describes about the history of the IBC modifications, design tools, configuration tools, material data, the process of testing tools and data comparisons between slickline and IBC.
Pore Pressure and Fracture Gradient Prediction for the Challenging High Pressure and High Temperature Well, Hai Thach Field, Block 05-2, Nam Con Son Basin, Offshore Vietnam: A Case Study
Authors: Nguyen Son T. , Hoang Son K. , Khuc Giang H. , Tran Hung N.
Published: October 2015

This paper discusses a case study of pore pressure and fracture gradient (PPFG) prediction for a development well in the high pressure high temperature (HPHT) Hai Thach field. Drilling in this field presented considerable challenges as the overpressure could reach 17.0-17.8 ppg and temperature could be as high as 185°C at well TD. Therefore, an accurate and practical approach on PPFG prediction along the planned well path is critical to prevent drilling problems (losses, gains, wellbore breathing, wellbore collapse, reservoir damage, etc.) and determine optimum placement of casing/liner strings. Before drilling, Eaton's method was used to predict the PPFG from seismic interval velocities, with calibration against measured pore pressures, Leak-Off Tests (LOT), and Formation Integrity Tests (FIT) from offset wells. During drilling, real-time LWD data, mud logging data, and newly acquired LOT/FIT measurements were used to continuously monitor and update the PPFG profiles. Critical points having big impacts on well design and execution such as entry into the overpressured zone and reservoir tops were afforded extra attention to ensure well safety, drilling optimization, and achievement of all well objectives. A geological model database for PPFG prediction was also continuously updated and validated with new drilling experiences and data such as gas readings, static mud weight, ECD, etc. Thanks to the systematic and practical approach, the PPFG profiles matched closely with field observations and the well was drilled successfully and economically.
Zonal Test and Adjustment for Low Flowrate Waterflooding Wells
Authors: Fuchao Sun , Yaning Liang , Liqiang Lu , Xiaohan Pei , Guohua Xiao , Huili Hu
Published: October 2015

There are more and more layers with low water injection rate in waterflooding oilfields such as daqing periphery, jilin, jidong and etc. The typical layered flowrate is usually 3-20m3/d. Layered low flowrate was still obtained by stepwise decline method no matter what downhole regulator is used. Test tolerance may reach 30% under this method for low flowrate test which result in poor accuracy. To improve low flowrate test accuracy, the method of collection flowrate test based on electromagnetic flowmeter was adopted. This paper designed a dowhnole instrument based on electromagnetic flowmeter which is used to test flowrate of waterflooding wells in oilfieds. Equipped with two active balls, the low fowrate test accuracy was enhanced through collection and increasing flow velocity which was effective to increase test accuracy for electromagnetic flowmeter. Then we did a group of laboratory tests. The results demonstrated the instrument based on electromagnetic flowmeter can keep the accuracy below 5% within the flowrate 3-20m3/d. Finally, an application case was introduced in jidong oilfieds with minimum flowrate 5.98m3/d. The application increased the accuracy and reduced the influence of interlayer interference. This technique can not only be suitable for the low permeability oilfield, but also for the conventional water injection wells.
Redesign of a Single String Packerless ESP-Gas Lift Hybrid
Authors: Rohman A. F , Arseto Y. I , Hamzah K
Published: October 2015

The Kaji-Semoga fields in South Sumatra, Indonesia, are mature, waterflooded oil fields with ESP's in more than half the wells. To minimize oil deferment due to down-hole ESP problems, an ESP-gas lift hybrid was implemented in 2009. The idea was to install gas lift as a backup so the well could be kept on production, albeit at reduced rate, until the ESP could be serviced or replaced. During the period 2011-2012, 97 wells had the hybrid lift system installed and ESP problems occurred 23 times in these wells. The availability of the ESP-gas lift hybrid minimized oil deferment and allowed approximately 24,000 bbls of oil to be produced while waiting for the ESP to be serviced or replaced.

However, the previous hybrid design used just a single gas lift valve as an unloader and injection point. Performance analysis of the previous design showed that the gas lift performance could be optimized if the injection point was, on average, about 300 feet deeper. But that would be too deep for unloading, so the gas lift hybrid system was redesigned by incorporating two gas lift valves, one a shallower unloading valve and the other a deeper injection valve.

Between April 2013 and March 2014, twenty-four wells had the redesigned ESP-gas lift hybrid installed. Performance analysis of the design was conducted at KS-XXX well when it had an ESP down-hole problem. After the redesigned gas lift was activated, it increased drawdown by 121 psi compared to the previous design, kept the liquid lifting to 57% of ESP production rate (compared to 25% of ESP production rate with the previous gas lift hybrid design) and minimized oil deferment leading to 540 bbls of additional oil production in this one instance. Analysis of the overall performance of the redesigned ESP-gas lift hybrid is onging, but results are similarly good.
The Influence of Fracturing Fluid on CBM Desorption-Diffusion-Seepage Capacity of Coal
Authors: Li Xiangchen , Chen Defei , Zhou Yu , Kang Yili , Meng Xiangjuan , Zhang Xinxiu
Published: October 2015

The production process of coalbed methane (CBM) includes desorption, diffusion and seepage, and the production is controlled by these three processes together. The permeability of coal reservoir is generally low. To increase the coalbed methane production, well stimulation needs to be applied, in which the contact between fracturing fluid and coal seam is inevitable. Developed micro-fractures, large specific surface area and high capillary pressure of coal generate serious damage easily caused by fracturing fluid, which can affect the production of coalbed methane. Therefore, the multi-scale mass transfer ability damage evaluation method considering CBM desorption-diffusion-seepage capacity was put forward based on the coal reservoir microscopic pore structure and coalbed methane migration output mechanism. Taking the NO.9 coal from Ningwu basin and fracturing fluid in site as the research object, comprehensive damage evaluation experiment of fracturing fluid on CBM desorption-diffusion-seepage were conducted in order to optimizing the fracturing fluid in construction site. Combining the methods of infrared spectrum, wettability, scanning electron microscope and coal mechanical experiments, the impact mechanism of fracturing fluid on CBM desorption, diffusion and seepage were analyzed. Results show that both the coalbed methane desorption rate and the diffusion coefficient of samples treated by fracturing fluid decrease compared with that of treated by formation water; compared with formation water, fracturing fluid can decrease the mechanical strength of coal and strengthen its stress sensitivity, microcracks close further under the action of geostress which will make the flow channel more narrow, eventually the seepage capacity decreases. Through the results of infrared spectrum, wettability and scanning electron microscope we can get the conclusion that fracturing fluid can change the surface structure, wettability and pore connectivity of coal, and affect the migration ability of coalbed methane. The field test of optimized fracturing fluid were conducted, the results are consistent with that of indoor experiment. This study can provide theoretical guidance for fracturing fluid optimization in the operation of coalbed methane wells fracturing.