bluuebunny/crossref_metadata_2025_split huggingface dataset:
Targeted Annular Hydraulic Fracturing Using CT-Enabled Frac Sleeves: A Case History from Montana's Bakken Formation
Authors: Castro Luis A. , Johnson C. Christopher , Thacker Christopher W. 
Published: September 2013

Abstract
Unconventional reservoirs require innovative completion techniques and technology to become more economical. Formations vary drastically in lithology, lateral lengths, completion methods, and financial drivers. Since reservoir conditions typically mandate the use of hydraulic fracturing for economical production results, a significant amount of resources are focused on making the fracturing process more efficient and lowering its environmental impact.
This case history includes an operational review focused on a novel technique to rapidly perform targeted annular hydraulic fractures by deploying an activation tool on coiled tubing (CT) to open frac sleeves in a horizontal well. The paper covers results and information gathered from the first operation of its kind in Montana's Bakken Formation – where a total of 19 stages were fractured in the shaley dolomite.
The new technology does not involve dropping balls or setting composite plugs to isolate stages. Rather, the technique utilizes frac sleeves that are activated using a CT bottomhole assembly to save time between stages. The sleeves can be cemented in place if desired and have a full-bore internal diameter that does not require post-treatment composite plug millouts, further reducing overall completion time and time to production. Additional capabilities of the system enable the use of memory gauges to monitor downhole pressure and temperature characteristics.
The operator preferred this method due to its targeted nature, efficiency, and fluid savings. As opposed to multicluster fracturing methods (such as ‘plug-n-perf"), a single entry point during the frac job promotes increased fluid velocity, enabling a more aggressive sand ramp and reduction in required hydraulic horsepower. Similarly, the single entry point ensures that a fracture is generated at each port, as opposed to the possibility that some clusters are not treated. In addition, no composite plugs or diverting devices are required to be pumped down the wellbore, so water usage is reduced considerably. The system, already used in thousands of fracturing stages in Canada, speeds up the completion process, uses less fluid, minimizes risks, and reduces overall downtime.
Fully Mechanical 3D Rotary Steering Technology Provides Economical Alternative To Conventional Rotary Steerable Tools
Authors: Herrington D. , Mercer S. 
Published: September 2013

Abstract
The demands of land-based drilling have evolved in recent years, requiring the drilling of complex, extended reach, horizontal wellbores to cross multiple production zones as well as to optimize the production of unconventional plays. Rotary Steerable System (RSS), technology is now being applied to enable drillers to meet today's directional challenges. The cost of operating these systems has limited their use to high profile land and offshore use in most cases leaving a technology gap to be addressed in markets with cost constraints.
Although RSS technology has proven its value in the field, adoption in low-cost applications has been limited. High lost in hole(LIH) rates, day rates that are double or triple that of mud motors, and harsh drilling environments that can lead to premature failure of RSS electronics are all barriers to the use of RSS in many land markets. The horizontal land market requires a technology capable of providing the performance of an RSS with a cost structure that doesn't place it out of reach for operators and regions on a limited budget.
Today a fully-mechanical rotary steerable tool has been developed that provides full 3D directional control during full rotation of the drill string without the high costs of conventional RSS tools and without the sensitive and costly electronics. This rugged and durable push the bit design withstands the most challenging of formations, and reduces the number of vibration related failures. Without the limitations of conventional electronics, this tool can also handle high temperature environments while improving ROP (rate of penetration) verse conventional RSS. A proven 3-point geometry and strategically placed stabilization are utilized to reduce tortuosity and drill a premium wellbore at a cost well below that of standard RSS.
This paper provides case studies from North American land operations proving the ability of this fully mechanical RSS to drill at ROP's up to 50% higher than a steerable motor. Reduction in operating cost of as much as 40% vs RSS and minimized financial risk associated with lost in holes charges (LIH) over conventional RSS are shown in the supporting study.
A Novel Mechanistic Approach for Modeling Low Salinity Water Injection
Authors: Kazemi Nia Korrani Aboulghasem , Sepehrnoori Kamy , Delshad Mojdeh 
Published: September 2013

Abstract
Waterflooding as a secondary oil recovery method is still the most commonly used technique for fluid injection since 1865. Recently researchers have discovered that the injected water quality is important and it should be monitored in addition to volume of water injected. This technique is known as low salinity water injection, LoSal®1, Smart Waterflood and Advanced Ion Management.
Evidence from laboratory studies, supported by several field tests, has distinctly shown that injecting low salinity water can have a significant impact on oil recovery. Although there are many LoSal® experimental results reported in the literature, publications on modeling this process are scarce. In this paper, we propose a mechanistic modeling approach for the low salinity water injection. We believe no matter the manner and details of mechanism, it ought to be all about ions. The key objective in this approach is to link the water-rock chemistry to changes in the state of a rock (e.g., wettability). Since geochemical reactions are the basis for this mechanistic modeling, we would need a geochemical engine to handle geochemical reactions in the reservoir for properly modeling LoSal®. Toward this goal, it was decided to couple IPhreeqc, an open source geochemical module available by United States Geological Survey (USGS), with UTCHEM, an in-house research chemical flooding reservoir simulator developed at The University of Texas at Austin. An algorithm is presented for modeling the geochemistry in an IMPEC (implicit in pressure and explicit in concentration) solution algorithm. Finally, we show how apply the integrated tool, UTCHEM-IPhreeqc, to model low salinity water injection.
Geochemical-based models can easily be implemented in this modeling approach and also compared against experimental results for validation. Implementation of several mechanisms can finally reveal the dominant mechanism for the low salinity water injection.
Sodium Free Processing of Oil Sands Ores: Toward Total Water Management in Mining Operations
Authors: Mahmoudkhani Amir , Fenderson Thomas , Watson Philip , Nair Mohan , Wu Yongfu 
Published: September 2013

Abstract
Current water management strategies require recycling and reuse of oil sand process water (OSPW) as much as 80%. Continuous recycling and reuse of OSPW results in a degradation of the quality of water namely increases of total dissolved solids (TDS) and dissolved organic materials (DOM). This results in a net increase in operating and maintenance costs and an impact on extraction process and bitumen recovery. Remaining water containing fines and suspended clays adds to the mature fine tailings and associated problems for tailing ponds treatment and management. Presence of residual bitumen and other organics is known to create difficulties in common practices for flocculation and dewatering of tailings. With problems stated above, one may consider a pre-treatment approach in place of the common post-treatment remedies.
The ore grade profoundly affects the efficiency of bitumen recovery in the hot water extraction of bitumen which is a principal step in the current commercial technology for bitumen extraction in mining operations. Sodium hydroxide is often added to the conditioning step of the process and is needed to obtain higher bitumen recovery from most oil sand feeds. Use of NaOH, however, results in accumulation of sodium ions in recycled water, causing higher clay dispersion and producing tailings with poor geotechnical properties that turn into mature fine tailings. This is especially true for low grade and oxidized ores, which present the greatest challenges in bitumen recovery and produce the major portion of tailings. With current trends for increasing production from mining operations to almost double by 2020, industry has to adopt new technologies to manage tradeoffs between water and energy.
We present a new approach toward total water management by introducing novel process aids for sodium-free processing of various oil sands ores. Lab experimental data were analyzed to evaluate the efficiency on the processability of low grade oil sands, water chemistry and tailing management. Our results demonstrate that the use of new process aids during the conditioning process leads to an improvement in bitumen recovery from low grade oil sands and can accelerate tailings settling resulting in better water management. The process aids were also used in combination of polymer flocculants to treat process tailings, resulting in better tailings dewatering and consolidation. This approach offers a potential chemical solution for total water management that can be incorporated into current ore processing facilities and delivers some operational and economic benefits.
Improved Reservoir Management Strategy via Limited Entry Multi-Stage Completion Boosts Production from Massive Carbonate Reservoirs in Saudi Arabia
Authors: Rahim Zillur , Al-Anazi Hamoud , Ahmed Mahbub , Al-Kanaan Adnan , El-Mofty Wael 
Published: September 2013

Abstract
Tight carbonate reservoirs have been successfully developed in various major plays around the world through the application of bespoke hydraulic fracturing and stimulation techniques performed in long horizontal sections drilled across these reservoirs. The main purpose of a typical stimulation program is to achieve the maximum and most efficient connectivity of the wellbore to the reservoir with the ultimate objective of long term productivity and recovery. Completion equipment design, efficient stimulation, and subsequent well performance have therefore gained attention starting from the early stages of design and planning.
Matrix acidizing of carbonate rock creates conductive flow channels also known as wormholes that possess much higher conductivity compared to the reservoir rock. These wormhole conductive channels transport reservoir fluids from within the formation matrix directly into the wellbore overcoming both low permeability and near wellbore damage. The treatment composition and more importantly the injection technique play significant roles in maximizing the number and depth-of-penetration of these wormholes and are among the most predominant design criteria for successful carbonate matrix acidizing, particularly in high pressure and high temperature environments.
One of the most successful technologies which has opened access to several major carbonate reservoirs and was recently tested is the limited entry matrix acidizing (LEMA) assembly. The assembly includes multiple jets in one selected interval flanked by isolation packers in an open-hole multi-stage completion designed to enhance controlled acid jetting (CAJ) into target sections. In principle, matrix stimulation is performed by placing acid treatments at the maximum possible rate, but at a pressure that is less than the formation fracture pressure. Diversion is achieved via limited entry placement of the acid treatment through multiple injection ports distributed along the stage length.
This paper presents an overview of the various methodologies used to stimulate moderate to high flow capacity carbonate reservoirs and the results obtained. An example of a purpose-built completion for more aggressive acid stimulation is presented and the results are discussed. The technique uses a system that is designed to run as part of the production liner to provide mechanical diversion at specified intervals, thereby allowing matrix acidizing treatments to be effectively placed in the target zones.
Case History: Sand Handling and Hydrocarbon Containment During a Coiled Tubing Cleanout of a Live Deepwater Well
Authors: Peruzzi Tave , Gagen Eric , Reynolds Randall , Cunningham L. E. 
Published: September 2013

Abstract
Procedures, photographs, diagrams, results and recommendations are shared from an operation to remove sand plugs from a high pressure deepwater well with a failed lower completion. Specific recommendations minimize risk and provide for the safe handling of sand on the surface as the oil passes below bubble point pressure and undergoes rapid expansion. This paper includes photos, diagrams and lessons learned from an operation conducted during the month of December 2011.
Removing sand plugs from a live well entails multiple risks. As the hydrocarbon is circulated to surface gas will evolve and expand rapidly, increase the velocity of the mixture and pose the risk of loss of containment due to erosion, especially if sand is entrained within the mixture. Any interruption to surface handling of wellbore fluids and sand creates the risk of stuck coiled tubing. Coiled tubing stuck inside production tubing in a live well would result in an unwelcome and probably difficult fishing job.

Literature Review
A number of papers on coiled tubing cleanouts are provided in the attached references. However none of the papers specifically address the safe handling of sand on surface.
Integrated Solution for Emulsion Diagnosis in Horizontal Production Logs
Authors: Ahmad Nawawi , Musharfi Nedhal , Zaouali Zouhir , Bawazir Mustafa , Al-Shabibi Hussain 
Published: September 2013

Abstract
Although various logging challenges in highly deviated and horizontal wells have been addressed in many previous studies, only a few investigations have focused on emulsion diagnosis and multiphase production log (MPL) solutions in such difficult conditions. The emulsion discussed in this paper is water-in-oil emulsion, in which water is present in the form of droplets dispersed in oil. This is generally expected to happen in a high velocity, turbulent flow regime, and in a low density contrast between oil and water. The impact of water emulsion is the inability to identify and quantify water entries using the standard holdup measurement arrays, because the water droplets have the same conductivity as oil and travel at the same velocity as oil, regardless of well deviation.
A novel workflow and methodology were established for successful diagnosis of this emulsion downhole to be able to perform inflow profiling for these problematic wells, using information from different sources of data: multiphase production logging tool (MPLT), pulsed neutron logging tool (PNLT), and surface fluid sampling. The workflow includes job preparation, real-time monitoring during logging operation, and post-job data interpretation.
The optimized workflow was applied to field examples for successful diagnosis of the emulsion and the integrated logging solution to overcome this challenge in horizontal wells. This led to the determination, with high confidence, of the downhole flow profile and to the accurate quantitative identification of the source of water production. The information can then be used to plan suitable well intervention, without which the reservoir and/or field development could not be optimized.
An atypical hydronephrosis revealing urinary tract involvement in antiphospholipid syndrome
Authors: De Moreuil Claire , Piette Anne-Marie , Hervé Jean-Marie , Camparo Philippe , Baglin Anne-Catherine , Blétry Olivier , Kahn Jean-Emmanuel 
Published: September 2013

Urinary tract involvement is rarely described in APS. We report the case of a 40 year-old man with primitive APS who was diagnosed an arterial and venous unilateral ureteral ischemia, revealed by a hydronephrosis. He had been on oral anticoagulation for six years because of two deep venous thromboses. He developed then a massive splenic infarct and an acute myocardial infarct, which required intensification of his anticoagulation, add of aspirin and high doses of corticosteroids. Three months later, he was explored for a latero-thoracic pain. Biology found an acute renal failure and microscopic haematuria. CT scan showed hypoperfusion of the left kidney, an ostial defect on renal artery and left hydronephrosis. Retrograde pyelography found a proximal ureteral stenosis. A dilatation with stenting failed, leading to a partial left ureteral resection. Histology confirmed ureteral segmental organized arterial thrombosis and venous thrombosis. Evolution was favourable with stabilization of creatinine level.Urinary tract involvement is rarely described in antiphospholipid syndrome (APS). We report the case of a 40 year-old man with primitive APS who developed an arterial and venous unilateral ureteral ischemia revealed by painful unilateral hydronephrosis. The patient was on oral anticoagulation for six years because of two deep venous thromboses. He developed then a massive splenic infarct and an acute myocardial infarct, which required the intensification of his anticoagulation and high doses of corticosteroids. Three months later, he was explored for a latero-thoracic pain. Biology found an acute renal failure and microscopic haematuria. CT scan showed a hypoperfusion of the left kidney, an ostial defect on renal artery and a left hydronephrosis. Retrograde pyelography found a stenosis of the proximal ureter. A dilatation with stenting failed, leading to a partial left ureteral resection. Histology confirmed ureteral segmental organized arterial thrombosis and venous thrombosis. Evolution was favourable with stabilization of creatinine. DOI: http://dx.doi.org/10.3126/jaim.v2i2.7659 Journal of Advances in Internal Medicine 2013;02(02):78-80
Liver Involvement Associated with Dengue Infection During A Major Outbreak in Central Nepal
Authors: Sedhain Arun , Bhattarai Gandhi R , Adhikari Shital , Shrestha Barun , Sapkota Abja 
Published: September 2013

Background and Aims - Dengue is a systemic viral infection, which is caused by any of the four strains of dengue virus and is transmitted between humans by the bite of Aides aegypti mosquito. Hepatic dysfunction is common in dengue infection with varying degree according to the severity of the disease. The aim of this study was to analyze the spectrum of liver involvement in dengue infection during a major outbreak that occurred in central Nepal between September and December 2010. Methods - A hospital based prospective study was conducted in the department of medicine at Chitwan Medical College. Patients who had fever in the ten preceding days (acute febrile illness) who had serologic evidence of Dengue and had no clinical evidence of bacterial infection anywhere in the body, were included in the study. Clinical, biochemical and radiological evaluation was done among 414 serologically confirmed Dengue cases to assess the spectrum of liver involvement. Statistical analysis of the data was done with SPSS version 16. Results - Dengue fever (DF) and dengue hemorrhagic fever (DHF) were present in 79.3% and 20.5% of the patients respectively. Only 2 out of 414 patients had dengue shock syndrome (DSS). The spectrum of hepatic manifestations included elevation of transaminases (raised ALT and AST in 81.9% and 57.7% respectively), abnormal abdominal ultrasound (49.3%), Hepatomegaly (39.1%), and Jaundice (4.1%). The intensity of hepatic involvement was significantly higher among patients with DHF than those with DF. Conclusion: Liver is one of the major organs to be involved in Dengue infection. Significant difference existed in the spectrum of liver involvement between DF and DHF. DOI: http://dx.doi.org/10.3126/jaim.v2i2.8775 Journal of Advances in Internal Medicine 2013;02(02):42-46
Prevalence of Helicobacter pylori infection, its correlation with gastroduodenal diseases and the incidence of gastric cancer in Nepal
Authors: Shrestha Umid Kumar , Ghosh Arnab , Alurkar Vijay M , Kohli Suresh C , Sapkota Subash 
Published: September 2013

Background and aims: The Helicobacter pylori (H. pylori) prevalence in Asian countries is highly variable, with higher seroprevalence shown in the previous studies of developing Asian countries. We aimed to determine the current H. pylori prevalence, correlate with gastroduodenal diseases and study gastric cancer incidence in Nepal. Methods: Among 3357 patients referred for endoscopy, 2820 eligible patients underwent upper gastrointestinal endoscopy with biopsy; H. pylori was considered positive when either of Rapid Urease Test (RUT) or histopathology showed positive result. Results: The H. pylori prevalence was 29.4% in overall distribution, 41.1% in gastritis and or duodenitis, 69.5% in gastric ulcer, 84.7% in duodenal ulcer, 20.8% in gastric polyp and 11.5% in gastric cancer. The H. pylori infection was significantly associated with gastritis and or duodenitis [P<0.001; Odds Ratio (OR) 1.53, 95% Confidence Interval (CI) 1.47-1.59], gastric ulcer (P<0.001; OR 18.62, 95% CI 12.40-27.81), duodenal ulcer (P<0.001; OR 48.89, 95% CI 25.23- 94.75), gastric polyp (P=0.001; OR 7.66, 95% CI 3.18-18.44) and gastric cancer (P=0.005; OR 3.78, 95% CI 1.82-7.86). The age-standardized (world) annual rate of gastric cancer in Kaski district of Nepal was 3.3 per 100,000. Conclusions: The H. pylori prevalence in Nepal was lower than that shown in the previous studies of developing Asian countries, but was significantly high in gastritis and or duodenitis, and peptic ulcers. Similarly, the gastric cancer incidence was also low in Nepal and was significantly associated with H. pylori. Further study is needed to establish the association of H. pylori with gastric cancer in Nepal. DOI: http://dx.doi.org/10.3126/jaim.v2i2.8777 Journal of Advances in Internal Medicine 2013;02(02):52-60
Study of lipoprotein (&alpha;) in patients of acute coronary syndrome and effect of low dose nicotinic acid on its serum level
Authors: Rajbhandari Rajib , Raut Roshan , Rajbhandari Sujeeb , Malla Rabi , Maskey Arun , KC Man Bahadur , Limbu Yubraj , Bhatta Yadab , Sharma Deewakar , Sharma Ranjit , Baidhya Sajan , Adhikari Chandra Mani , Prajapati Dipankar 
Published: September 2013

Background and aims - Lipoprotein(a) is not an established independent risk factor. This study aims to observe whether lipoproteina(Lpa) is significantly high in patients of acute coronary syndrome (ACS) in comparison to healthy control. The second part of the study is aimed to know whether oral nicotinic acid treatment lowers Lpa level significantly. Methods - This is a prospective case control study with quasi-experimental design done on acute coronary cases admitted in our centre. Total 200 cases of ACS were included as cases and 46 healthy volunteers were controls. In later part of the study those patients who had high Lpa and were eligible were treated with nicotinic acid for 3 months and Lpa was measured again. Results - Mean Lp(a) level was 39.7mg/dl (±17) among the 200 ACS cases admitted in CCU with the maximum of 83 and minimum of 14. Among controls mean Lpa was 22mg/dl (±3.04) with maximum of 44 and minimum of 17mg/dl. Difference was significant with p value of < 0.01. It was observed that nobody discontinued the drug because of side-effects. In these patients there was significant reduction in serum Lpa level from 74.1mg/dl (± SD22.2) to 43.2mg/ dl (± SD21.9) p<0.01. Conclusion - The serum level of Lpa was significantly high in patients with ACS patients in comparison to control. This difference however was not significant between STEMI and NSTEMI patients. Low dose Nicotinic acid reduces Lpa significantly and is well tolerated by the patients. DOI: http://dx.doi.org/10.3126/jaim.v2i2.8778 Journal of Advances in Internal Medicine 2013;02(02):61-64