bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of the Jet Pump to the Slim Hole Production Wells at Onshore Thailand
Authors: Ishihara Ryujiro , Higuchi Naohide , Mikami Yohei 
Published: March 2021

Abstract
This is a case study to establish the positive result of an artificial lift application of the jet pump (JP) system using the coiled tubing (CT) and the macaroni tubing (MT). It is applied to the monobore completions for the slim-hole production wells on BURAPA-A oil field, onshore Thailand, implemented by Siam Moeco Ltd. (SML, Affliated Company of Mitsui Oil Exploration Co., Ltd.). As a result of the JP introduction, the resulting production decline rate was lower and the recovery factor more than doubled, which extended field life longer than expected. SML succeeded in discovering the method to minimize the capital cost while maximizing the oil recovery with the JP system. This method has given us the chance to conduct a smaller-scale well intervention operation with only minor modification of the wellhead. We believe that it is an adequate artificial lift application for the small-size oil field.
Some important lessons for the small pipe size operations were learned in this process. A pin-hole leak was detected in the CT for the main production well due to erosion and corrosion by continuous high-pressure pumping for around two years after the installation of the JP completion. After reviewing the new completion design, the type of deployment pipe was converted to the MT, which is thicker and has higher integrity than the CT. Consequently, there have been no integrity issues for the deployment pipes since the production was resumed with the new completion. In addition, using the multi finger caliper tool, it was detected that the thickness of the production tubing at the jetting area was significantly eroded, showing that the JP system has the possibility to risk the integrity for the outer string.
The JP completion is a validated technology to apply for the slim-hole monobore completions to increase the recovery factor and minimize the implementation cost. In addition, the well integrity risk by the JP application to the slim-hole monobore completions was revealed, and new insights were gained, resulting in some pros and cons comparing the two types of the deployment pipes (CT & MT).
The Color of Energy: The Competition to be the Energy of the Future
Authors: Lau Hon Chung 
Published: March 2021

Abstract
Energies may be described as brown, blue or green. Brown energies are CO2-emitting fossil fuels. Blue energies employ carbon capture and storage (CCS) technologies to remove the emitted CO2 from brown energies. Green energies are zero or low CO2-emitting renewable energies. Likewise, energy carriers such as electricity and hydrogen may be described as brown, blue or green if they are produced from brown, blue or green energy, respectively. The transition from a high carbon intensity to a low carbon intensity economy will require the decarbonization of three major sectors: power, transport and industry. By analyzing the CO2 intensity and levelized cost of energy (LCOE) of energy and energy carriers of different colors, we show that renewable energies are best used in replacing fossil fuels in the power sector where it has the most impact in reducing CO2 emission. This will consume the majority of new additions to renewable energies in the near to medium future. Consequently, the decarbonation of the transport and industry sectors must begin with the use of blue electricity, blue fossil fuels and blue hydrogen. To achieve this, implementation of large-scale CCS projects will be necessary, especially outside of USA and northern Europe. However, this will not happen until significant financial incentives in the form of carbon tax or carbon credit becomes available from national governments. Furthermore, private-public partnership and intergovernmental cooperation will be needed to implement these CCS projects.
Fines Migration Behavior During Cyclic Injection and Production of Underground Gas Storage Wells
Authors: Chen Mingjun , Shao Jiaxin , You Lijun , Kang Yili , Meng Seng , Yang Guang 
Published: March 2021

Abstract
Different injection and production pressure modes for underground gas storage have great differences on the permeability of formation rocks. In this paper, core flow experiments are designed and carried out to simulate the real pressure gradient of the injection and production in underground gas storage, and these experiments are carried out under in-situ stress conditions. The permeability and turbidity of core outlet were monitored during the experiment. The experimental results show that under different injection-production pressure modes, the permeability changes and the turbidity at the core outlet changes. It was observed by scanning electron microscope that there were fines on the fracture wall after the experiment. Analysis shows that fine migration is the main reason for the change of permeability under different injection-production pressure modes.
Small Scale Skid-Mounted Natural Gas to Hydrogen Production System Provides Competitive Hydrogen for China
Authors: Song Pengfei , Wang Rui , Sui Yiyan , Shan Tongwen , Hou Jianguo , Wang Xiulin 
Published: March 2021

Abstract
Because of its convenience, high efficiency and low cost, small-scale skid-mounted hydrogen generator has become a hydrogen-production object of intense research efforts worldwide and has broad prospects in application. We analyze the technical points and difficulties in detail of this kind of on-site compact hydrogen generators from natural gas, by each section in the production process. It is suitable for integrated hydrogen refueling stations due to easy transportation and installation. Related applications are introduced by comparing the technical parameters of recent typical products in the world. Meanwhile, we calculate that the full life cycle cost of hydrogen from skid-mounted hydrogen generator from natrual gas can achieve less than 40CNY / kgH2, which is more economic than other possible hydrogen sources and transportation modes of a hydrogen refueling station. Although the advantages mentioned above, we point out that technology innovation is still desirable, especially in the process of reforming, automatic control, system integration and catalysis, to realize the minimization of skid-mounted hydrogen generators base on natural gas, for its further and wider application in the future.
Robust Dynamic Toolface Calculation for Automatic Steering Control with Rotary Steerable Systems Under Extreme Conditions
Authors: Ramakrishnan Ganesh , Demirer Nazli , Tilley Jim 
Published: March 2021

Abstract
Reliable toolface calculation is essential for achieving robust automatic steering control with rotary steerable systems (RSS). For RSS with fully rotating sensor packages, this task becomes particularly challenging under extreme conditions, where signal-to-noise ratio (SNR) of measurements from one or more sensors reduce significantly (e.g., while drilling near-vertical wells, along dip, towards magnetic north, in the vicinity of casing and/or under severe vibration and stick-slip). To ensure robust toolface control for fully rotating RSS under these conditions, this paper proposes a novel dynamic toolface calculation method.
The proposed dynamic toolface calculation method of the new-generation fully rotating RSS overcomes the challenge of achieving robust toolface control despite extreme drilling conditions, by bringing together real-time health monitoring, online sensor calibration and novel sensor fusion techniques. Considering that robust toolface control is the heart of any drilling automation architecture with RSS, this technology is key to enable advanced drilling control strategies in the future.
A New Method of Pressure Analysis of Well-Test Data from a Well in a Multi-well Reservoir with no Flow Boundary Condition & New Diagnostic Plots to Differentiate Between the Boundary and Interference Effects
Authors: Cobanoglu Mustafa 
Published: March 2021

Abstract
If the interference effect is not considered for well test interpretation, it could lead to wrong analyses especially in boundary identification. In addition, there are some case where interference effects might be hidden where it may not be obvious due to data uncertainty. Therefore, special diagnostics of the multi well interference models will be required to differentiate between the boundary and interference effects. In addition, there is no analytical method for a well in a multi-well reservoir with no flow boundary condition.
In this paper a new method was developed to model Pressure Analysis of Well-Test Data from a Well in a Multi-well reservoir with no flow boundary condition. It covers;
Derivation of the analytical model, based on the superposition principle, with and without "no flow" boundary condition; Modeling of various combination of testing & interfering well cases (i.e. testing well is on production or shut-in while interfering well is on production or shut-in) Modeling of various combinations of testing & interfering well rate cases (i.e. production or injection, rate variations) Modeling of various number of interfering well cases (i.e. location and well count) Investigation deeply on how to differentiate between the boundary and interference effects (or vice versa) and developing the special diagnostics to able to detect interference effect directly.
Results are shown that 1) the multi-well interference effect with and without no flow boundary condition has huge impact on the well test interpretation and this effect might be interpreted as a boundary effect if interference is not considered. 2) Build-up (BU) behavior of testing well is depending on whether interfering well is shut-in or producing. If interfering well is producing, pressure derivative of BU curve is concave down and If the interfering wells are shutting in, pressure derivative of BU curve is concave up 3) the interfering well rate is affecting magnitude of impact on pressure derivative and the higher the rates, the bigger the response 4) the interfering well distance is affecting the timing of deviation on pressure derivative and the closer the distance, the quicker the response
Study also concluded that there are 3 special characteristics, which only exists in interference cases, and which does not exist in boundary cases. Therefore, those characteristics can be used to differentiate between the interference and boundary effects. Those are 1) Pressure decrease or rise at the beginning of well testing 2) the drawn-down (DD) and BU pressure derivatives in Log-Log plot are different (i.e. when BU is concave up, DD is concave down or vice versa) in case of interfering well is on continuous production 3) The consecutive BU's (or DD's) pressure derivatives on Log-Log plot are different and changing over time
Feasibility Study on Optimisation of Material Selection for High Temperature Sour Gas Producer
Authors: Nordin M. Helmi , Moh Wahi M. Wahidullah , Sashidharan Amresh , A. Karim Nurfuzaini , Ramli Alif Syahrizad 
Published: March 2021

Abstract
K field is a green field in East Malaysia with prolific gas reserves that is being developed with six high rate gas producing wells from high temperature (190 °C) carbonate reservoir. Tubular material feasibility study is one of the key subjects of scrutiny when it comes to completing wells in high temperature environment coupled with existence of significant level of H2S and CO2 contents. Material testing was conducted at the specified test environments (102 bar CO2 + 120ppm H2S) and load cases to assess susceptibility of Martensitic Stainless Steel to Stress Corrosion Cracking (SCC), corrosion rate and compatibility with completion brine. The aim was to optimize the material selection that is fit for purpose (lower completion and flow-wetted area of production casing) and reduce well cost up to USD 2.5 million.
The base case of material selection for flow-wetted section is 17CR110 ksi, which meets the design requirements of these wells based on fit for purpose test conducted in the data base. Flow-wetted section in this case is production liner and flow-wetted section of production casing below production packer. Super 13CR -110 ksi and 15CR125 ksi material grades were considered for design optimization for this section of interest. Four Point Bend Method was used for SCC test sets while weight loss method for corrosion rate measurement. For brine compatibility test, calcium bromide (without additive) was used as test solution for 17CR 110 ksi, 15CR 125 ksi and Super 13CR -110 ksi with elevated temperature of 190 °C.
Post-test assessment was conducted by visual examination by stereomicroscope to check for surface indication and dye-penetrant examination to determine any indication of cracks. It was observed that the Super 13CR -110 ksi and 15CR 125 ksi test specimens survived the test with no pitting observed. Meanwhile, test specimens were weighed to determine corrosion rates, resulted to Super 13CR -110 ksi sample having an average corrosion rate of 0.2195 mm/year. This translates to less than 30% weight loss throughout well production life and therefore accepted for open-hole production liner and production casing flow-wetted section.
Key enabler in this design optimization effort is the understanding of the Stress Corrosion Cracking for martensitic stainless steel in high temperature sour environment where commonly, martensitic stainless steel (Super 13Cr / Modified Super 13Cr) working temperature is 165 °C. The test manages to extend the working temperature up to 190 °C.
Successful Application of Rigless Fully Retrievable ESP System in Bohai Offshore Oilfield, China
Authors: Shang Baobing , Li Junfei , Fang Tao , Yu Fahao , Han Xiaodong 
Published: March 2021

Abstract
In bohai offshore oilfield, about 98% oil wells produce with electric submersible pump (ESP). For the common ESP system, workover is needed to replace the failed pump about every 4 years, resulting in significant operation cost and production lost. To solve this problem, a new type of rigless fully retrievable electric submersible pump (RFR-ESP) is developed and applied in bohai oilfield.
This paper mainly introduces the technical details of the used RFR-ESP system, and the real application effects in typical wells. This new system consists of downhole permanent part and retrievable part, with the power cable clamed externally along with the tubing. The core of the system is a specially designed wet connector system. Through this connector, any ESP manufacture's equipment can be used. For this technology, the retrieval of ESP can be finished by standard oilfield wireline operation, and no rig workover is required any more. Till now, two different systems suitable for 7″ tubing and 5-1/2″ tubing have been developed in order to meet the yield of different wells.
Bohai oilfield installed the first RFR-ESP in 2013. Up to now, 6 wells have applied this technology, including one water source well and five oil wells. The longest running time of the ESP is about 2000 days, and it is still in service now. The maximum liquid production is about 2800m3/d. For this new system, the workover time of ESP replacement reduces from 10 days to about 2 days comparing to the traditional rig workover process, and the number of the workover operators reduces from 30 to about 10. All of these are helpful to reduce the workover cost and the production lost. Besides, several problems encountered in the wells, such as power cable failure provides valuable field experience for the promoted application in bohai offshore oilfield.
The successful application of this technology indicates that it has the potential to lower ESP operating costs, and even improve the artificial lift status of offshore oilfield. What's more, this new system is expected to be used in unmanned platform, thus no workover boat is needed any more, which will drastically cut down the development cost.
Combining Sparse Data with Reaction Kinetics Using Fuzzy Logic to Predict Reservoir Souring
Authors: Kathrada Muhammad 
Published: March 2021

Abstract
Hydrogen Sulphide (H2S) is a colourless, flammable and highly toxic gas with a strong odour of rotten eggs that is found in many reservoir fluids and aquifers in the world. This gas is commonly a result of "reservoir souring" – a process which increases the H2S concentration. Increasing amounts of this gas pose serious health, safety and environmental concerns. This can result in significant costs associated with replacement of downhole and surface equipment and increased processing costs, but more lethally a potential loss of life.
Many reservoirs particularly those undergoing waterflooding face increasing levels of hydrogen sulphide (H2S) production with time. H2S is a highly toxic gas that can be fatal even at low concentrations. Being able to predict the risk potential of a particular reservoir to increasing H2S production with time would be highly valuable. The objective is to determine apriori whether a reservoir would likely see dangerously high levels of H2S being produced during the lifetime of the reservoir, and if so, be a catalyst in supporting further investigation and mitigation of H2S early in the reservoir development.
There is very little published field data with regards to reservoir souring, hence a purely data driven model would not be possible to create. However, we do have a good understanding of the reaction kinetics that goes into the biological process that generates H2S. To this end the best modelling paradigm that can assimilate sparse data with first principles dynamics is fuzzy logic. A fuzzy logic model has been built around the reaction kinetics and then conditioned to the published field data. The model created matches the published field data fairly well. It is now a ready tool that can be used by engineers to make a quick assessment of their reservoirs before going into full blown expensive sampling and laboratory analysis.
The novel aspect of this paper is being able to use fuzzy logic to combine the first principles chemistry together with sparse data to produce a model that can be used practically. Fuzzy Logic has been out of the news of late as machine learning and neural networks are the current hot potatoes, however it is often overlooked that fuzzy logic can still be used in low dimensional cases where only sparse data is available.
Effect of Nano Carbon Spheres on the Properties of Oil-Based Drilling Fluids under High Temperature Conditions
Authors: Zhong Hanyi , Kong Xiangzheng , Qiu Zhengsong , Huang Weian , Zhang Xianbin , Zhao Chong 
Published: March 2021

Abstract
Owing to superior temperature stability in comparison with water-based drilling fluids, oil or synthetic-based drilling fluids are generally preferred for high temperature and high pressure (HTHP) formations. However, the thermal degradation of emulsifiers and polymeric components under HTHP conditions that results in loss of rheological and filtration control, barite sag or even fluid phase separation also occurs. It is a challenge to sustain these properties stable under such harsh condition.
Since nanoparticles have potential to provide better thermal stability, improved filtration loss as well as emulsion stability, the aim of this study is to investigate the effect of nano carbon spheres on the properties of oil-based drilling fluids under high temperature conditions. The nano carbon spheres were synthesized with the hydrothermal reaction of glucose. The influence of nano carbon spheres on the rheological, filtration, emulsion stability, settlement stability, as well as lubricity of a typical mineral oil-based drilling fluid with oil to water ratio of 80:20 was investigated before and after thermal aging at 180 and 200°C, respectively.
The structure characterization showed that the uniform hard nano carbon spheres exhibited intermediate wettability. Laboratory performance test indicated that, for the oil-based drilling fluid, the addition of nano carbon spheres improved the rheological properties in terms of yield point and the ratio of yield point to plastic viscosity, which is beneficial for transporting of drilling cuttings. After thermal aging at 200 °C, the filtration loss volume was reduced as high as 70%, and desirable filter cake quality was obtained by incorporation of 1.0 wt% spheres, meanwhile the electrical stability was improved both before and after thermal aging. Furthermore, the fluid formulated with the nano carbon spheres generated better barite sag control. The polarizing microscope observation showed that the nano carbon spheres accumulated at the water-oil interface and formed a steric barrier which probably explained the reason of the above enhanced performance.
The green synthetic routes and environmental friendly characteristics of the nano carbon spheres, in combination with the excellent properties suggested that the nano carbon spheres hold potential as multi-functional additives for formulating oil-based drilling fluids for HTHP drilling operations.
A Story of Material Selection For Completion Tubing in HPHT Gas Fields in the Past 20 Years, Western China
Authors: He Xinxing , Wang Kelin , Fan Wei , Liu Hongtao , Long Yan , Xie Junfeng , Fu Anqing , Deng Peng , Jiang Tianhong 
Published: March 2021

AbstractKuqa foreland basin, which is located in the western of China, has the characteristics of HPHT with high CO2 partial pressure, and covered Yaha, Kela, Dina, Dabei, and Keshen gas fields. This story dated back to 2000 year that Yaha gas field was put into production, and the reservoir temperature 140°C, pressure 56 MPa, depth 4900-5300 m, and CO2 concentration 0.7-1.3 %. Carbon steel was selected for tubing material in the early stage of field development. After about 3 years, tubing perforation was caused by serious corrosion. Then carbon steel wasupgrade to 13Cr. However, it was found that there was serious corrosion in the connection part of tubing, and the corrosion was caused by the CO2 and condensate water.Based on the experience in Yaha gas field, the modified 13Cr tubing was used in the Dina2 gas fields, and the reservoir temperature 140C, pressure 110 MPa, depth 5200 m, and CO2 concentration 0.26-1.02 %. Although the well condition is less harsh, serious corrosion still occurred concentratedly on tubing pin end. Considering premium tubing leak in Dina field happened during acidification operations, and the results of series simulation tests conducted, the understandings were achieved that acid will cause serious corrosion to the inner wall of tubing, aslocal corrosion is dominant factor of stainless steel.The super 13Cr material was used in Keshen gas field which has reservoir temperature 150-188C, pressure 105-136 MPa, depth 6000-8038 m, and CO2 concentration 0.1-1.1 %. However, tubing fracture happened one by one, which originate from stress corrosion cracking caused by mixture of phosphate packer fluid and killing mud. Therefore, material selection needs to considerthe compatibility of different fluids, and formate was chosen as packer fluid. By December 2020,it has been used in 103 wells of Kuqa foreland basin, abnormal annular pressure is presented in 6 Wells, and the longest service time is six years.As the rapid exploration and development of Kuqa foreland basin, the proper material selection become more difficult for gas reservoir temperature more than 190C and its pressure greater than 140 MPa, the past practices about material selection may provide the reference, and the story about material selection will be continued.