bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reservoir Sensitivity Evaluation by Monitoring Displacement Experiment with X-ray CT Imaging
Authors: Weifeng Lv , Zhenpeng Leng , Qingjie Liu , Ninghong Jia , Manli Luo , Tong Li , Xu Jin , Jianhua Qin , Zhibin Jiang 
Published: October 2015

Abstract
When designing an oilfield development plan, reservoir sensitivity is a non-negligible consideration due to its direct relation to the formation damage and its influence on the consequence of field output. Traditionally, reservoir sensitivity is evaluated in laboratory by conducting different types of flow experiments from which the variation of core permeability is analyzed. However, due to the lack of sufficient insight vision, this traditional method only reflects the macroscopic phenomena but fails to reveal some important microscopic behaviors inside the core during the process of flooding, such as the fingering of the flooding front, the effective sweeping area or the position of the formation damage, etc. In this paper, a new method, which combined the displacement experiment and the X-ray CT imaging technology, was introduced to effectively observe and characterize the water sensitivity to various flooding scenarios. Formation core samples drilled from the same reservoir layer were used for the displacement experiments while simultaneously being monitored by X-ray CT imaging. The water sensitivity was analyzed by investigating the visualized flooding process from X-ray CT images and quantitatively characterizing the displacement behaviors under differing scenarios. Two new variables, virtual porosity and relative porosity, were proposed in terms of CT numbers in the X-ray CT images to investigate the water sensitivity. It could be shown from the experimental results that the formation damage occurred only near the inlet end where the average porosity decreased by 10% to 15%. Porosity reduction of large pore area was relatively higher than that of small pore area by comparing initial porosity histogram with final virtual porosity histogram. Physical explanation of this water sensitivity phenomenon was deduced that the porosity was reduced by the swelling of chemical reaction product between brine and clay minerals, which resulted in the reduction of CT numbers.
The Impact on Drilling Programme Design of Shallow Gas Detection Using Passive Ultrasound Integrity Survey
Authors: Nussbaum Chris V. , Khlustikov A. , Sarigih J. M. , Reza R. A. , Anuraga E. , Mamesah J. D. 
Published: October 2015

Abstract
This paper is a case study of field data, assessing the impact of a well integrity survey on an on-going development drilling programme, enabling critical management of an unexpected shallow gas risk.
The results and conclusions presented are applicable to the diagnosis and risk management of shallow gas zones and their impact on well construction, design and integrity.
The well Operator experienced a severe loss of well control during drilling operations in the Western Block of Talang Jimar field in Sumatra. The field is mature and the well was considered routine in a series of more than 200 drilled over the past 50 years. A kick occurring at a relatively shallow depth around 300m was completely unanticipated.
It was judged critical to further drilling to investigate the location and extent of the charged interval. This would identify HS&E and operational risks to be mitigated by modification of both the on-going drilling plan and the well design. The clearest and most precise information was required.
When active surface gas venting was discovered at an adjacent well, an ultrasonic annular integrity survey was commissioned to determine the subsurface source of the gas. This ultrasonic survey deploys a number of sensors on wireline in the well, the most important being a passive ultrasound detector.
The paper describes the survey technique in brief, the results of the successful survey and the modifications made to the well and mud-weight design to manage the shallow gas risk and the benefits for the drilling programme.
The new results presented reveal annular flow outside surface casing with clarity, and the paper explores the underlying reasons for this clarity and its potential benefits for shallow-gas applications.
Field data is presented to support the conclusions reached.
The methods and technology described in the paper will be of interest, as they should be widely applicable to shallow gas integrity diagnosis, whether a surface gas vent or sub-surface cross flow, in both onshore and offshore applications. Such diagnosis may enhance drilling and production HS&E performance, reducing the risk of well-control incidents.
The Application of Face Direction Perforating in Unconventional Reservoirs
Authors: Gao Yang , He Liu , Liangang Wang , Yucai Wang , Qinyou Ye 
Published: October 2015

Abstract
The types of reservoirs are more and more complex with the deepening of the exploration and development, and it comes up with a new challenge for perforation completion technology. A new perforating technology is urgent to match up with the reservoirs to improve oil and gas well productivity or create channel conditions for well stimulation, and it is a new requirement to the emergence of unconventional reservoirs. As the middle part of this kind of reservoir development, perforation must be to create a better channel condition for well stimulation, to reduce the rock fracture pressure, induce fracture extension direction, and perfect reservoirs fracture network system. Face direction perforating adopt extra large perforation diameter bullet and special hole arrangement, multi-holes are formed in the same cross section which is perpendicular to the axial of the casing, it can form stress concentration along the wellbore's cross direction, and can effectively control the trend of the fracture, reduce formation fracture pressure, avoid cross collusion of fractures between different segments, and improve the perfect degree of fracture network system. The casing damage research and parameter matching optimizing between casing and face direction perforating are completed by establishing casing damage mathematical model of face direction perforating under different working conditions, the initiation and extend direction of hydraulic fracture after face direction perforating was studied as well, and then it is implemented in the field. Test showed that face direction perforating can reduce formation fracture pressure by 15% or more, oil production increased more than 20% after hydraulic fracture compare with conventional perforating and fracture.
Facile Synthesis of Polyimide Aerogel Usable under Harsh Conditions for the Separation of Oil and Water
Authors: Jin Xu , Xi Tongdi , Liu Xiaodan , Wang Xiaoqi , Sun Liang , Yang Qinghai , Zhang Li , Wu Juntao 
Published: October 2015

Abstract
With increasing environmental awareness, novel strategies to effectively separate oil from industrial wastewaters and polluted oceanic water are highly desired. Using special wettability to design new materials for oil/water separation is an effective and facile way. Herein, polyimide (PI) aerogel is designed and prepared by freeze-drying PI precursor poly(amic acid) ammonium salt (PAS) water solution followed by imidization. With high hydrophobicity, the PI aerogel can be used for the absorption and separation of oil and water. 30–195 times weight of organic pollutants and oils can be absorbed by PI aerogel. To demonstrate the cyclic distillation test, cyclohexane was absorbed by the PI aerogel. As the size and the porosity structures of PI aerogel stayed the same during the separation/distillation cycles, no obvious change in absorption capacity was found after five cycles, indicating the highly stable recycling performance. During separation, water quickly permeated through the PI aerogel and dropped into the beaker below, while oil was retained above it and no external force was employed. Additionally, PI aerogel is also usable under harsh conditions. This research paved the way for fabricating high efficient and recyclable oil/water separation PI aerogel which can be used in the petroleum industry in the future.
Automated Optimization of Interdependent Artificial Lifting Fields Using Integrated Response Surface Model and Hybrid Heuristic-Gradient Algorithm: A Field Case Study
Authors: Ekkawong Peerapong , Kritsadativud Pannayod , Lerlertpakdee Pongsathorn 
Published: October 2015

Abstract
The generic characteristic of producing fields in Gulf of Thailand (GOT) is that oil wells are also developed on the same facilities as gas wells when possible. Different efforts are taken to optimize both oil and gas wells together. Gas-lift is one of the examples of artificial lift that is installed in oil wells. For gas wells, booster compressor (BC) is common facility on platforms to reduce back pressure to each producer routed to the unit. The situation can get even more complex when gas from the BC is used as a source for lifting gas in an oil well.
This paper extends the novel automated optimization workflow of gas field optimization (Ekkawong P. et.al. SPE-173450) and oil field with gas-lift optimization (Kritsadativud P. et.al.SPE-174039) to maximize production from more complicated gas/oil fields with various combined artificial lifting systems. Firstly, to improve calculation efficiency, the production performance estimated by NODAL analysis is transformed into a multi-dimensional response surface model (RSM) as a relationship between flowing pressure, gas injection rate and oil production. This transformation significantly eases the computation burden. The RSM is then used as the well performance prediction tool to be used in a production optimization workflow using hybrid optimization algorithm, the combination of heuristic and gradient based optimization. Genetic Algorithm is roughly searching for the global optimum solution, and then the gradient based method is used to further refine the solution. The process is run repeatedly with different initial guesses to ensure the optimality of the obtained solution.
The benefit of this method is demonstrated in a synthetic field that illustrates the complex offshore field in GOT. This field features oil and gas wells with interdependent artificial lift equipment: gas-lift and BC. The objective is to maximize field oil/condensate production under other field operating constraints. The controllable parameters are: amount of gas to be injected into each oil well, well to be routed to BC, and wellhead flowing pressure from each well. The result of this proposed workflow shows increase in oil production honoring all practical constraints. Additionally, the computation time is also significantly reduced from the conventional approach using manual fine-tuning and the integrated NODAL analysis modeling.
This automated workflow simplifies the more complex process to be a much more computationally efficient and easy to understand. Hence, it can be used as the tool to optimize day-to-day production operations in the complex fields that the conventional tool is obstructed by the computational burden.
Preformed Particle Gel Propagation Through Super-K Permeability Sand and Its Resistance to Water Flow During Conformance Control
Authors: Imqam Abdulmohsin , Bai Baojun , Delshad Mojdeh 
Published: October 2015

Abstract
Excess water production has long been considered a major problem leading to the life-shortening of oil and gas wells and operational problems. High-permeability streaks, fractures, conduits, and fracture-like features can expedite an undesirable water channeling and early water breakthrough during water flooding. Preformed particle gel (PPG) is one of the commercial gels invented exclusively to plug such features to reduce excess water production, improve sweep efficiency, and increase oil production. This paper reports the results of laboratory experiments that studied the PPG's injection and placement mechanism through Super-K permeability cores to reduce unwanted water production and increase oil recovery. Extensive experiments were conducted to examine the effect of the sand permeability, PPG size, concentration, and water salinity on the PPG injection process, passing criteria, and plugging efficiency to water flow. A two foot sand pack model with four pressure taps was designed to monitor PPG transport and plugging performance. The results showed that the PPG propagated deep into the sand pack. PPG's in-depth permeability reduction to the core was dependent on the PPG size, strength, concentration, and sand permeability. Fully swollen gel particles had better injectivity than partially swollen particles with a larger diameter size; particle strength was more dominant in influencing particle movement than was particle size. The injection pressure increased as the PPG concentration, water salinity, and gel particle size increased. A large injection pore volume was required for the PPGs to be produced at effluent when both the water salinity and particle size were increased and when the PPGs concentration decreased. PPG transport through Super-K permeability sand exhibited three patterns of injection processes based on both the threshold pressure and the injection pressure measurements across the sand pack cores: low gel particle retention and pass; high gel particle retention and pass; and high gel particle retention, breaking, and pass. After the PPG injection process was completed, cycles of saline water were injected into the sand pack to test the PPG's resistance to water flow. The PPG's blocking efficiency to water flow increased as the PPG strength, size, and concentration increased. The PPG placement mechanism, such as washout, was also found to considerably affect the water injection flow processes. The results of this laboratory experiment will aid in the selection of future conformance control candidates and also optimize the particle gel treatment design for large-scale field projects.
Novel EOR Strategy-Decision System Based on Delphi-AHP-TOPSIS Methodology
Authors: Liang Bin , Jiang Hanqiao , Li Junjian , Gong Changcheng , Ding Shuaiwei , Mi Lidong 
Published: October 2015

Abstract
EOR strategy decision has been considered as a thorny process, which depend on proper evaluation, rational understanding of the complex relationships, and quantitative assessment of the multiple relevant factors, including economy considerations, dynamic field production, reservoir numerical simulation and other related factors. A decision making system based on Delphi-AHP-TOPSIS methodology is developed to meet this challenging problem, and the technological process is divided into three phases. The first phase is Delphi method, where analysis of undisturbed, identification according to professional theories and quantitative evaluation of key performance factors and sub-factors are implemented and an effective measurement scale is carried out. The second phase is Analytic Hierarchy Process (AHP) based on EOR performance of several selected strategies, so as to investigate EOR performance of correlative factors and sub-factors, along with synthesis influence of the factors. What's more, the third phase is Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) depending on evaluation of candidate solutions whose utility function show monotone decreasing or increasing characteristics. A typical EOR strategy case is presented for better understanding, which is known as polymer flooding strategy. The proposed strategy-decision methodology has proved useful for decision making, helping engineer acquire more comprehensive understanding of the relevant factors in existing scheme and choose the better alternatives. The approach can not only minimize decision makers' bias, combining influence of financial and technical factors, but also facilitate the decision makers to make the best response to the oil market and the reservoir dynamic performance rationally. The proposed system is successful application of the Delphi-AHP-TOPSIS methodology for EOR scheme decision, through the Delphi, the quantitative evaluation of the influencing factors can be obtained without inappropriate analysis and the AHP and TOPSIS procedures can identify better practices from the analysis of the comprehensive influence of individual factors and sub-factors. Thus the optimal EOR strategy can rise to the surface.
Decision Support System on Pipeline Replacement of 200 kilometers Main Oil Transport Pipeline in a Very Mature Oil Block
Authors: Azwar Noezran , Migas SKK , Agus Pramudyana 
Published: October 2015

Abstract

Objectives/Scope
The objectives of the research are to establish decision support system for pipeline replacement. The scope of the research is 2005 – 2014 inspection data on 200 kilometers main oil transport pipeline in one of mature oil block under Production Sharing Contract. The incident varies from small leak, rupture, congeal, and to the most: hit by trucks incidents.

Methods, Procedures, Process
Research starts in 2005 – 2014 after first leak in 2005. The research performed with many investigation methods, from visual inspection, in line inspection, long-range ultra-sonic method, to magnetic tomographic method. Results from those investigation used for short-term action and used for risk analysis. Risk analysis conducted from process hazard identification and analysis, to risk based inspection analysis. SWOT analysis also performed to make conceptual decision for the replacement. Front End Engineering Design (FEED) was conducted to replace the pipeline. Quantitative Risk Analysis for new pipeline is included in FEED.

Results, Observations, Conclusions
Pipeline inspection performed since 2005 shows there were significant wall thickness loss at the pipeline. Short-term action has performed by installing pipe metal sleeve. This procedure significantly reduces numbers of leak incident. The predictive and preventive maintenance is performed every year to assure safe pipeline operation. Inspection on right of way shows significant population growth along the pipeline route. Inspection shows rapid growth in land encroachment, illegal crossing, and illegal tapping activities along right of way. Police records shows "pipeline hit by truck" occurred every year. Short-term action has already performed to protect the right of way including access limitation, hazard signs, and fencing. Unfortunately, these actions do not reduce the numbers of incident significantly. All inspection data and records become inputs for process hazards analysis and risk based analysis. Risk based analysis shows most of 200 kilometers pipeline sections are exposed to high risk. Pipe metal sleeve do not reduce overall risk significantly yet. Pipeline is highly exposed to third party risk. SWOT analyses shows pipeline replacement with new route are required to significantly reduce the calculated risk.

Novel/Additive Information
This paper shows a structured decision support system is required in the very first step of project to make conceptual decision massive pipeline replacement in a very mature oil block.
Reservoir Characteristics for Unconventional Shale Play of Huai Hin Lat Formation in Northeastern Thailand
Authors: Chumkratoke C. , Dunn-Norman S. 
Published: October 2015

Abstract
Recent trends in petroleum production have focused on developing unconventional gas reservoirs such as tight gas and shale gas. Considering worldwide shale gas resource potential, the largest reserves exist in the former USSR and in North America, while for China, Central and Southeast Asia the estimated shale gas reserve is 1115 TCF. Despite the smaller reserve projection, this unconventional resource is of great interest for future development. In Thailand, the primary energy source is oil and natural gas, with 77% of electricity generated from natural gas (EIA, 2011). Yet current production is not enough to support the growing energy demand in Thailand, and there is increasing emphasis in exploring potential unconventional resources to meet this demand.
A study has been conducted to improve reservoir knowledge of the Huai Hin Lat formation, believed to be an important source rock for the gas fields in northeast Thailand. The Huai Hin Lat formation consists of fluvio-lacustrine sediments of Late Triassic. The formation is exposed along the margin of the Khorat Plateau. Petroleum exploration in Khorat Plateau has been ongoing since 1962 and two gas fields have been discovered and commercially produced in the Khorat Plateau since 1988.
Seven shale samples were taken from the Huai Hin Lat formation. All samples are the organic rich fine-grained rocks. The MicroCT technique was measured for porosity paramter. The average porosity of the samples was approximately 4.9%, and a pore size distribution was found. In addition, geochemical analysis was performed to determine total organic content (TOC) of the shale samples. The average TOC was found to be approximately 4.9%.
Permeability was measured for the seven samples using transient pressure pulse decay. The permeability range of the samples was found to be 90 nD to 280 nD and the average permeability of sample was approximately 180 nD. Permeability varies significantly because of the shale is somewhat heterogeneous.
This paper provides details regarding the analysis of the Huai Hin Lat samples and the shale's rock properties as they relate to other commercial unconventional gas resources. The work is significant because there are few existing petrophysical evaluations of this formation. Results from this study will identify and highlight key reservoir parameters necessary to further assess the commercial potential of the Huai Hin Lat shale as a shale gas reservoir.
Jointly-Developed Novel Torque Transducer Ensures Jack-up Rig Integrity
Authors: Wang J. K. , Delves C. , Li D. W. , Cooper M. , WU J. W. , Van Millingen J. , Qiu T. S. , Sleath C. , Wang J. M. 
Published: October 2015

Abstract
To ensure the integrity of offshore jack-up rigs, a novel torque transducer has been developed through 18-month-long joint collaborations cross industries globally.
A medium size offshore jack-up rig uses a set of fifty-four units of AC-driven jacking systems to jack the platform up and down. Due to inevitable manufacturing tolerances and poor correlation between motor current and its torque at standstill and near-zero speed, the synchronization and even load distribution among the fifty-four climbing pinions of these jacking systems has been a challenge. Uneven load sharing among these fifty-four climbing pinions can overload and then break some of them prematurely. Broken climbing pinions can result in catastrophic rig accident and human casualties.
This novel torque transducer measures the climbing pinion resistant torque directly through reading the torsional deflection of the pinion precisely. A series of design verification through finite element analysis and design validations through factory acceptance tests have been conducted successfully.
With this new torque transducer installed, the load on each climbing pinion can be read simultaneously and then controlled either manually or with a variable frequency drive.
Different from any existing standard torque transducer mounted between electric motor and the input shaft of jacking system, this new novel torque transducer is designed to be mounted inside the climbing pinion and then reads the torque load on the pinion directly. The accuracy of this direct torque reading is regardless of the gear transmission efficiency, which, in fact, governs the reading accuracy of the current existing standard torque transducers available in the market.