bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbon Nanotube under High Pressure
Authors: Al-Awami Ali H. 
Published: October 2018

Abstract
Nanotechnology is considered as the next major industrial revolution. It deals with materials at a molecular and atomic scale and is predicted that it will affect all aspects of our lives. Nano-materials are a major branch of nanotechnology that is characterized by different behaviors. One of the promising nano-materials that are expected to play an important role in industry is the carbon nanotubes (CNTs). The CNTs improve the efficiency of many tools, e.g., energy storage, electrical cables, and ultra-capacitors.
CNTs exhibit very different features under extreme conditions, such as high pressure. In addition, doping carbon nanotubes with nitrogen might enhance their performance and allows them for more advanced applications. In this study, we examined nitrogen-doped CNTs (CNX-NTS) under high pressure. We used 1.5% and 5.4% CNX-NTS samples that were exposed to pressure range up to 15 GPa. For both samples, there was no phase transformation. The two sample’s results suggest that doping of nitrogen strengthens the mechanical property of CNTs.
As the results showed, that CNX-NTS can overcome high-pressure rates (more than 15 GPa), and they can be used in applications that encompass high pressure. For example, in oil and gas industry, CNTs can be used in protecting oil and gas operation equipment and structures to provide protection, increase the service life, and decrease the maintenance cost.
Wettability Alteration of Oil-Wet Calcite: A Mechanistic Study
Authors: Gmira A. , Hammami M. A. , Al Enezi S. M. , Yousef A. A. 
Published: October 2018

Abstract
Enhancing oil recovery in naturally fractured reservoirs by injecting chemistry-optimized water has been widely investigated recently and has demonstrated its efficiency at both laboratory and field trials. There is an extensive ongoing efforts in the industry to characterize and understand the responsible mechanisms at scales ranging from nano-scale to field scale. The ionic formulation of the injected brine affects dramatically the crude oil/brine/rock interfaces, altering rock wettability and improving oil recovery efficiency. In this experimental work, a mechanistic study is performed utilizing analytical methods to study the effect of the ionic composition and ionic strength on the rock sample wettability. The combination of Thermogravimetric Analysis (TGA) and Fourier Transform Infrared (FTIR) spectroscopy is a time saving experimental approach, suitable for wettability alteration quantification of rock samples. The results indicate that stearic acid stretching vibrational bands decrease with the decrease of brine ionic strength indicating a partial release of adsorbed organic material from calcite surface. Single ion brines impacted the calcite wettability and sulfate ions were found to be the most effective in stearic acid release followed by sodium, calcium and magnesium. Thermogravimetric analysis confirmed the observed trend and the calcite weight loss due to stearic acid decomposition decreased with decreasing brine ionic strength and confirmed the fact that sulfates ions are the most effective in partial release of adsorbed stearic acid from calcite surface.
Utilization of Advanced, 3D Numerical Models Built With Interference-Test Data for Understanding Regional Hydraulic Connectivity in a Carbonate Reservoir
Authors: Amin Rana S. , Wehaibi Bandar A. , Alghazal Mohammed A. , Rahman N. M. 
Published: October 2018

Abstract
Due process has been followed in launching this focused study, starting with integration and analysis of available static and dynamic data to characterize selected sectors of the subject reservoir. The objective of this initiative is to build 3D numerical models for characterization of the hydraulic connectivity within the sector models. These sectors have been originally taken out of the corresponding static geological models. Some of the wells in the sectors have data from prior transient tests, which have been utilized to condition the permeability around the corresponding wells. But this step has not been found enough to describe the dynamic behavior on a long term. Hence, data from a multi-well, interference test has been utilized to enhance the dynamic characteristics of fluid movement in the numerical models.
This paper presents an integrated approach to characterize the hydraulic communication and heterogeneity in the reservoir. The results of this study have helped improve reservoir characterization in the corresponding part of the reservoir simulation model, providing a more refined input of dynamic pressure and permeability data within the area of interest. Best of all, the reservoir engineers have acquired a wealth of knowledge of reservoir connectivity to be utilized for their reservoir management practices.
Rock Grain Size Prediction from NMR Measurement and Digital Rock Modeling- Experimental Validation
Authors: Ma Shouxiang , Jin Guodong , Sy Rex , Kesserwan Hasan 
Published: October 2018

Abstract
This paper presents an experimental study to test and validate a technique of predicting rock grain size distribution (GSD) from nuclear magnetic resonance (NMR) measurements and digital rock modeling. GSD is one of the basic parameters in geo-science and petroleum engineering. Such information is commonly obtained from sieve or laser particle size analysis in the laboratory on a limited number of core samples. The measured GSD is then approximated to be representative of the targeted reservoir rock. A technique that estimates a continuous GSD profile along a wellbore embodies a significant technical and economic advantage.
In this paper, GSD was predicted from NMR responses of fully water saturated rock samples using digital rock modeling techniques, which generates a rock model and simulates NMR responses by considering mineralogy, surface relaxivity and the surface roughness of rock grains. For validation, NMR measurement, GSD, mineralogy, and permeability measurements were performed on the rock samples used for digital rock modeling. Three outcrop Berea sandstone samples were used in this study; one for calibration to tune the modeling parameters and the other two for validation. The sieve analysis method was used to measure the GSD, in which petrographic observation was applied to confirm that grains were properly disaggregated.
Results from this study indicated that sample composition played a key role in the prediction of GSD from NMR measurements, because grain surfaces change with mineralogy and are affected by diagenetic processes. A parameter, surface roughness factor, was used to account for these effects. For Berea sandstone samples, if its composition is assumed to be pure quartz, the predicted GSD could not match with the measured one. Once the measured mineralogy was used in the modeling, it agreed well with the measured GSD. The same parameters were further used to predict GSD for all remaining Berea sandstone samples, with satisfactory results.
The presented methodology may be applied downhole to predict a continuous GSD profile of a reservoir interval, providing that mineralogical composition and an NMR log are available. Drill cuttings or prior knowledge based on cores can also provide such information. The predicted GSD provides useful information for geo-science and petroleum engineering applications such as permeability prediction.
Emulsifier Developed from Waste Vegetable Oil for Application in Invert-Emulsion Oil based Mud
Authors: Ramasamy Jothibasu , Amanullah Md , Alsaihati Mujtaba M 
Published: October 2018

Abstract
Emulsifiers are a class of chemicals derived from fatty acids or their derivatives and used in water-in-oil based mud (OBM) in other words invert emulsion oil based mud. The role of an emulsifier in invert emulsion OBM is to lower the interfacial tension between water and oil to allow the formation of stable emulsion which is an essential quality of oil based mud. These emulsifiers surround the water droplets like an encapsulation with the fatty acid components extend into the oil phase and acts like a small osmatic cell allowing only water to pass through but not salts. Most of the commercially available emulsifiers are derived from Tall oil fatty acid (TOFA) which shows excellent emulsion stability even at harsh conditions. Our objective in this study is to make use of the huge quantity of used cooking/vegetable oil available in the kingdom and convert to an emulsifier suitable for the application in invert-emulsion OBM as vegetable oil contains a wide range of different fatty acids in the form triglycerides. A comparative study has been carried out by formulating invert-emulsion OBM using commercially available emulsifier and the emulsifier derived from used cooking/vegetable oil. Emulsifier (Arc-Eco-Mul) from used or waste vegetable oil has been synthesized by an in-house developed process. A series of different invert-emulsion OBM have been formulated with varying density using in-house developed product Arc-Eco-Mul as primary emulsifier. For comparison, a mud is formulated using commercial primary emulsifier. Mud properties such as density, rheology, API and HPHT filtration control tests have been conducted for fresh mud and for muds hot-rolled at 300degF and 500psi for 16h. It is observed from the laboratory experiments that the mud samples formulated using 12-ppb of Arc-Eco-Mul have similar rheological properties and better filtration control properties compared to the mud samples formulated using 12-ppb of commercial emulsifier. Most importantly, there is no phase separation in the filtrate collected from HPHT filtration control experiment, which showed a very stable emulsion formed by in-house developed Arc-Eco-Mul. Concentration screening experiments showed that only 6-ppb loading of Arc-Eco-Mul is required to achieve a mud with very good rheological and filtration control properties with high emulsion stability. The in-house developed Arc-Eco-Mul from used cooking/vegetable oil has similar properties as commercial additives that are currently used in the industry. This will open an avenue for recycling used cooking oil for oil and gas industry applications.
Corrosion and Scaling Monitoring under Real Downhole Conditions in Sour Gas Wells
Authors: Chen Tao , Chang Frank , Liang Feng , Mukhles Amro 
Published: October 2018

Abstract
One of the major challenges of corrosion and scaling management in sour gas wells is to effectively monitor corrosion and scaling under real-flow regime conditions. It is very difficult to simulate the actual environment and flow conditions in laboratory experiments to study downhole corrosion and scale formation. Understanding the corrosion and scaling mechanism under downhole conditions is very important in order to develop effective prevention and mitigation strategies in a timely manner.
An advanced downhole corrosion and scale monitoring (DCSM) tool has been designed and developed to monitor corrosion and scale formation in sour gas wells. This monitoring system represents significant improvements over the current industrial technology by directly measuring corrosion and scale deposition in real downhole conditions using exchangeable coupons with identical metallurgy as the downhole completion tubing. A slick line with a retrievable high-expansion gauge hanger was used to deploy and anchor the DCSM downhole at the desired depth. The tool was retrieved after 3 months exposure to the reservoir conditions for post-laboratory analysis. Advanced analytical techniques were carried out to understand the corrosion and scaling mechanism, including SEM, EDS, XRD, and surface profile measurement besides quantifying the weight changes.
The results showed that a thin layer (~3-4 μm in thickness) of iron sulfide scale was deposited on the surface of coupon. It served as a protective layer to prevent and reduce further corrosion and scale buildup. To understand the mechanisms of scaling, the surface scale deposit was removed by corrosion inhibited acidic solution. The surface profile measurement showed localized pitting corrosion which appeared on the surface of coupon, which indicates that corrosion happened first followed by scale layer deposition on metal coupon surface.
The newly developed DCSM tool has an advanced design which allows direct corrosion and scaling monitoring under downhole conditions. Post-laboratory analysis on retrieved coupons can provide corrosion and scaling mechanism for specific metallurgy under real downhole conditions. Proper corrosion and scale management programs could be designed to minimize the effects of corrosive gases. The developed tool can be used to monitor the effectiveness of the corrosion treatment and can be deployed in sweet gas wells, oil wells and water supplier wells.
High Density Drilling Fluids for Managed Pressure Drilling
Authors: Wagle Vikrant , Al-Yami Abdullah S. , Aljubran Mohammad , Al-Bahrani Hussain 
Published: October 2018

Abstract
Drilling with high density water-based muds invariably increases the chances of a stuck pipe. Stuck pipe significantly increases the cost of drilling and decreases the chances of successfully drilling a well within the stipulated time. Drilling fluids formulated with a combination of manganese tetroxide and barite as weighting agents are expected to have the following advantages: a) Better sag resistance b) Lower equivalent circulating density (ECD) c) Lower fluid cost d) Stuck pipe mitigation due to acid solubility of manganese tetroxide. This paper describes the formulation of 100pcf, 120pcf and 150pcf drilling fluids formulated with a combination of barite and Mn3O4 as weighting materials and hot rolled at 270°F/250°F/300°F respectively. The experimental work involves measuring rheological properties, HTHP filtration and static sagging resistance of the fluid at the specified temperature. The paper also describes the data obtained from the field trial of 160pcf fluids formulated with barite and Mn3O4 for wells with a BHST of 300°F. Details are shed on the high-pressure, high-temperature (HPHT) operations across naturally fractured formations with 0.5 - 1.0 pcf mud window.
The paper discusses the advantage of using such drilling fluids in mitigating stuck pipe issues and showcases their benefits in terms of better barite sag resistance and lower equivalent circulating density as compared to conventional drilling fluids formulated with barite as weighting agent. The 100pcf, 120pcf and 150pcf fluids showed superior rheology, thin filter-cake and better sag resistance as compared to fluids formulated with only barite as the weighting agent. The drilling fluids formulated with a combination of barite and manganese tetroxide showed good rheology, barite-sag resistance and resulted in successful drilling of wells having a BHST of 300°F. 160pcf fluid formulated with a combination of barite and manganese tetroxide when field trialed showed good rheology, better sag-resistance thereby resulting in successful drilling of the well. In fact, managed pressure drilling (MPD) operations became more practical with such high mud weights as this novel formulation facilitates mud management and treatment when compared to the conventional recipes. MPD control algorithms are absolutely dependent on the mud system consistency and durability which is a feature provided by this innovative fluid formulation.
New Epoxy Chemistry to Generate Highly Conductive Channels Within the Fracture Geometry Pillar Fracture
Authors: Baqader Nour O. , Kalgaonkar Rajendra A. , Gomaa Ahmed M. , Al Moajil Abdullah M. 
Published: October 2018

Abstract
A conventional proppant pack may lose up to 99% of its conductivity due to gel damage, fines migration, multiphase flow, and non-Darcy flow. Therefore, the concept of pillar fracturing was developed to generate highly conductive paths for hydrocarbon to flow. The success of the pillar fracturing treatment depends on delivering the proppant as pillar stages with a good suspension. This suspension keeps the proppant within the stage, prevents the proppant from diffusing out of the stage, and improves the mechanical strength of the pillar during closure. Resin based chemistries were proposed in the literature for proppant pack consolidation. However, most of these resins are incompatible with the aqueous fracturing fluids. This warrants for special precautions to be undertaken during pumping of the treatment to avoid formation damage.
This paper discusses a new chemistry that has been developed to substitute the porous proppant pack in the fracture with an isolated structure of propped pillars containing a network of open channels. Also, this paper further discusses the experimental procedures to test compatibility of the newly developed chemistry with crosslinked fracturing fluids, optimization to use the minimum concentrations, and making hard plugs of proppants pillars under pressure and temperature (up to 350°F). Furthermore, proppant suspension tests with and without pulsing were conducted at temperatures up to 300°F to evaluate the ability of creating the conductive channels. Finally, the mechanical strength of the created pillars was evaluated using triaxle load frames to confirm that the created pillar will resist the closure stress and keep the fracture open.
Experimental results showed that embedded fluid after gelation can transport the proppant during the injection and closure time without settling, thus avoiding any issues with proppant screen outs. The compatibility test showed that different concentrations of the embedded gel fluid (from 20-50 vol %) was compatible with crosslinked fracturing fluid and fracturing fluid additives. Moreover, this new chemistry was able to suspend the proppants. Additionally, the consolidated proppant pack showed excellent mechanical strength enhancement with the developed fluid system where the proppant pillar can hold the fracture open at high closure stress. Also, it was interesting to notice that oxidizer breakers enhanced the mechanical strength of the developed proppant pillar. The created pillar was conductive and hydrocarbon flowed through it.
The data obtained from this study showcases the development of a new fluid chemistry that can replace conventionally used techniques to transport proppant inside the fracture.
A Novel approach for Mitigation of Shocks & Vibration and achieving drilling performance in carbonate reservoirs
Authors: Balka Muhammad Sarfraz , Ghazzawi Ayman , Melgares Hernan 
Published: October 2018

Abstract
Deep gas drilling in carbonate environment is very challenging due to elevated temperatures with pressures. Additionally, the presence of the shock and vibrations across the interbedded layers of limestone and dolomites. Over the years different drilling techniques are employed for improving the drilling performance. The analysis of the data showed that the wells where the shock and vibrations were lower the optimum performance was achieved and the section was drilled in one run compared to the wells where multiple runs were required because of shock and vibration. Further analysis showed that the Shocks are not only seen while drilling, but the level of shocks was high during non-drilling activity such as reaming during wiper trips, back reaming across tight spots and before reaming while connection. This paper will cover the techniques that were employed to minimize the S&V or at least reduce to the minimum acceptable level where the drilling performance can be achieved.
Understanding the shock and vibration across different formations and sub layers within formation. Comparison of shock and vibration for different BHA's while drilling. Application of the stat of the art drilling dynamic simulator. Comparison of BHA's with standalone and motor power Rotary steerable system. Identifying and developing the strategy while crossing the interbedded layers. Feedback to the reliability team for improvement.
Based on understanding the shock and Vibration, and lesson learned multiple wells are drilled where the number of BHA's used to drill the section are reduced and the ratio of drilling the section in one runs is increasing.
High-Performance Water-Based System Proved an Environmentally-Friendly Alternative for Time-Sensitive Shales in Saudi Arabia
Authors: Hegazy Mohamed , Sharma Sunil , Fares Khaled , ElBatran Ahmed 
Published: October 2018

Abstract
The Khafji and Ahmadi shales in Saudi Arabia are highly dispersive, tectonically stressed formations and tend to result in wellbore instability after prolonged exposure to conventional water-based drilling fluid systems. These time-sensitive formations can cause sloughing shale, packing off, extreme over pull, back reaming, stuck pipe, and in some instances bit and stabilizer accretion, resulting in non-productive time (NPT) to operators. Some off-set wells experienced lost time of up to 30 days, and after failing to continue with conventional water-based drilling fluid, the operator had to plug back and use oil-based drilling fluid to finish the wells.
Historically, a standard KCl/polymer/asphalt system was used to drill these shale sections, but due to related NPT and an extensive evaluation program planned for a candidate well, the need for a more robust fluid was identified. Oil- or synthetic-based drilling fluids were not desired due to logistical and environmental concerns. In this challenging well, the operator planned to cut five cores across a series of formations to complete the geological studies previously hindered due to shale-related wellbore problems. These demanding objectives and the notorious history of the field, required a novel solution that could control the formations while maintaining an excellent environmental and logistical footprint.
This paper presents details of the successful application of a new high-performance water-based drilling fluid (HPWDF) system using a unique triple inhibition approach to stabilize troublesome zones. In this new system, a proprietary polyamine-based shale hydration suppressant, a unique low-molecular-weight encapsulator, and a co-polymeric nano-sized pore-sealant additive worked in synergy to achieve oil-based fluid performance. In the field application, the system exceeded the operator's expectations, with no fluid-related downtime and successful execution of five coring runs. After coring and logging, casing was run and cemented smoothly, even after 42 days of wellbore exposure. With similar formations drilled across the Middle East, this solution has the potential to be used as an environmentally-friendly alternative to oil-based fluids in the Middle East.