bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Moved Oil Volume and Viscosity with NMR and Dielectric Dispersion Logs in a Heavy Oil Sandstone Reservoir Under Steam Injection
Authors: Claverie Michel , Yaliz Ayk , Bris Elsa Le 
Published: March 2016

Abstract
We examine the vertical profiles of moved oil volume and oil viscosity in the monitoring well of a steam injection pilot project. The oil volume and viscosity were assessed with petrophysical logs during the drilling of a monitoring well located near the centre producer of the producers-injectors pattern.
Prior to drilling the monitoring well, steam was injected for several months at the bottom of the sandstone heavy oil reservoir to increase the oil temperature and decrease its viscosity. As the monitoring well was drilled, water filtrate from the drilling fluid displaced a fraction of the reservoir oil proportional to the effectiveness of the steam flood; within the zones of elevated reservoir temperature, the oil viscosity was reduced and the mud filtrate invasion deeper.
As the reservoir oil is viscous, the displacement induced by the water filtrate is small – the filtrate invasion is shallow. Monitoring this displacement therefore requires log measurements with a small depth of investigation, even smaller than the flushed zone resistivity Rxo from a micro-laterolog. In this work, we evaluate the moved oil volume and the viscosity of the reservoir oil from the combination of magnetic resonance porosity, T2 relaxation time and D diffusion constant, and of water-filled dielectric porosity at 2 depths of investigation.
The water volume deep into the reservoir is compared to the NMR free fluid volume and to the deep and shallow dielectric water-filled porosities to identify the zones and calculate the volumes of oil displaced by filtrate. The NMR station measurements of T2 relaxation time and D diffusion constant provide a direct evaluation of reservoir oil and water volumes as well as an estimate of the in-situ oil viscosity after steam flood.
The profiles of fluids volumes after filtrate invasion confirm the effective vertical extent of the steam flood at the monitoring well and also provide a proxy to the residual oil volume under dynamic reservoir conditions. These volumes, controlled by the heavy oil shallow displacement by filtrate are only observable and measureable from the NMR and dielectric dispersion logs.
This method, applied for the first time in an offshore steam injection pilot, is applicable in the open hole conditions of drilling the monitoring well. However, derivatives of this method can be applied in cased hole – NMR logs have been recently acquired in radio-transparent glass-reinforced epoxy casing with suitable temperature rating for steam injection.
Miscible Gas EOR Pilot Design Decisions Driven by Linking EOR Performance Parameters to Uncertainties - A Kuwait Field Example
Authors: Sharma Shashank , Kamal Dawood , Al-Maraghi Eisa , AlMahrooqi Sultan , Winkler Mario 
Published: March 2016

Abstract
Many decisions in enhanced oil recovery (EOR) pilot design are required to plan an EOR pilot that, if executed successfully, gives a reliable data set and sufficient information to make full field EOR development decisions in the future. A miscible gas EOR pilot was designed for the formation "X" in the field "Y" of Kuwait using an uncertainty driven approach.
The method presented in this is paper is a qualitative way of linking key miscible gas EOR performance parameters of the formation to the intrinsic uncertainties of the properties impacting them. An assessment of the impact of the uncertainty itself, likelihood of impact and the acceptance, or required uncertainty reduction, provided the direct link to the selection of the pilot concept, the pilot type, the pilot location and the operational sequence of executing the pilot.
The key miscible EOR performance drivers for the formation in, with unacceptable high uncertainty, are vertical sweep efficiency (Ev) and remaining oil saturation (ROS). Hence it was decided a non-producing pilot with a single injection well and with observation well(s), is the EOR pilot concept and type enabling data gathering to address the above key uncertainties. The pilot area and pilot location was assessed via a semi-quantitative assessment of more than 10 parameters impacting miscible gas injection EOR, for example remaining oil, recovery factor, and pilot location distance to producers. While the final goal of the miscible gas EOR development for the formation is a miscible CO2 flood, it was decided to use produced hydrocarbon (HC) gas as a pilot injectant. This addresses the key objectives of the pilot with sufficient accuracy, while avoiding costly and timeline infrastructure changes at this early stage of understanding the chances of a successful EOR development.
The additive information to the audience is the consistent approach of using an uncertainty based assessment of key EOR performance drivers throughout the entire pilot planning steps and defining pilot objectives, pilot concept and type as well as pilot location.
Key Learnings from First 2 Years of a Full Field CSS Development in Oman
Authors: Bettembourg Solenn , Holyoak Steve , Alwazeer Abdullah , Manhali Mohammed , Rawahi Mohammed , Habsi Amur 
Published: March 2016

Abstract
The "A" East Haradh formation contains a 200 m thick oil column of highly viscous oil, with viscosity ranging from 200 to 400,000 cp. Due to the high viscosity, first production was considered only possible using thermal EOR techniques, starting with Cyclic Steam Stimulation (CSS). The field has now been in operation for more than two years, with a number of wells already into a third CSS cycle.
This paper will focus on the key learnings derived during this initial operations phase of CSS in "A" East Field including, amongst others, key trial results on different well completions and artificial lift systems combined with new insight into the reservoir architecture. In addition, reservoir performance management is being streamlined through the development of a structured approach to the CSS planning and using dedicated visualisation. Automated Exception Based Surveillance "triggers" are currently being developed to efficiently address any deviation from the operating envelopes and further optimise the recovery from this 81 well CSS development.
Based on the very encouraging performance to date, the company has already sanctioned a further 34 well CSS expansion of the current development with drilling scheduled to commence in 2016.
Mechanistic Simulation of Residual Oil Saturation in Viscoelastic Polymer Floods
Authors: Lotfollahi Mohammad , Koh Heesong , Li Zhitao , Delshad Mojdeh , Pope Gary A. 
Published: March 2016

Abstract
Polymer flooding is one of the most widely used enhanced oil recovery methods due to its good performance in numerous large commercial field projects and its relative simplicity and low cost compared to most other enhance oil recovery methods. The main mechanism is considered to be improved sweep efficiency, but numerous studies have also reported lower residual oil saturation to polymer than to water. Because the results depend on many variables such as the initial oil saturation, rock characteristics and polymer characteristics, such experiments must be performed at reservoir conditions and at controlled capillary numbers and so forth to measure the reduction that applies to field polymer floods. Furthermore, a mechanistic model is needed to scale up the laboratory coreflood results to the field.
We implemented and tested the new model for the residual oil saturation in a mechanistic numerical reservoir simulator. The simulation model was used to match the oil recovery and pressure drop of both secondary and tertiary polymer flood experiments. The results showed a strong correlation between the remaining oil saturation and the Deborah number.
Partition Coefficient Relations in Surfactant-Oil-Brine Systems for Improved Description of Microemulsion Phase Behavior
Authors: Torrealba V. A. , Johns R. T. 
Published: March 2016

Abstract
Surfactant mediated enhanced oil recovery techniques such as surfactant-polymer (SP), and alkaline-surfactant-polymer (ASP) flooding, have received increased attention in the past decade due to their ability to reduce capillary forces at the pore-scale to ultra-low values and mobilize oil. In order to improve the economics of such processes, a better understanding of the interaction of surfactant-oil-brine systems is needed. Recently, an equation-of-state (EoS) has been developed that significantly improves microemulsion phase behavior prediction based on coupling of the HLD-NAC equations with a new correlation of optimum conditions, and an updated hydrophilic-lipophilic difference (HLD) model that includes pressure (Ghosh and Johns 2014, 2016). The new EoS accounts for gradients in key formulation properties relevant for reservoir-scale processes in a robust and noniterative framework. One common assumption of all existing microemulsion phase behavior models is the assumption of pure excess phases, which says that the surfactant component can only be present in the microemulsion phase. The focus of this paper is to allow for surfactant partitioning into both the water and oil excess phases, and then relate the relevant surfactant partitioning coefficients to the HLD state function so that K-values, and potentially phase behavior, can be predicted.
This paper derives important relations of the surfactant partition coefficient between relevant phases based on a chemical potential description of the HLD, which measures the deviation from optimum conditions. In particular, we calculate the surfactant partition coefficients from numerous experiments in the literature and show that the surfactant partitioning coefficient has a linear scaling with HLD for a wide variety of formulation variables. Surfactant K-values between excess phases from all experiments examined collapse onto the same linear relationship so that once HLD is known (based on formulation variables such as salinity) the K-values are explicitly determined. The estimation of surfactant partition coefficients can be used to aid the design of surfactant formulations for EOR processes.
Experimental Investigation of Dimethyl Ether/Polymer Hybrid as an Enhanced Oil Recovery Method
Authors: Chahardowli Mohammad , Farajzadeh Rouhi , Bruining Hans 
Published: March 2016

Abstract
Injection of Dimethyl Ether (DME) dissolved in water can enhance the recovery efficiency with respect to water flooding. In this Shell Proprietary Technology, DME partitions from water into the oil; decreases oil viscosity and increases its volume, and mobilizes the trapped oil again. In this work DME-enhanced water flooding is combined with polymer and considered for cases in which a favorable mobility control between water and oil does not exist.
In order to reduce the remaining oil, slugs of the mixed solution of DME and polymer was injected into the cores containing oil and then followed by injection of a chase fluid. This recovery method benefits both (a) from the presence of polymer, and the oil viscosity reduction caused by DME dissolution and (b) from oil swelling due to DME dissolution.
It appears from experimental data the injectivity of a DME/polymer (DMEP) solution is higher than the injectivity of a polymer solution without DME indicating that presence of DME can reduce the viscosifying effect of the polymer. The main experimental observations are: (1) a higher oil recovery is obtained from continuous DMEP flooding than from continuous DME-brine Flooding, (2) the presence of polymer in the DME slug and in the chase phase reduced the remaining oil after a finite slug injection, (3) a larger DME slug and mobility control of the chase phase can improve the oil recovery after a finite slug injection. In summary, the experiments show that combining polymer and DME improves the ultimate recovery significantly and shortens the duration of oil production.
North Sabah EOR ADP – Examining the Challenges of Offshore ASP Development
Authors: Kovalev K. , Agarwal B. , Harris R. , Jaspers H. 
Published: March 2016

Abstract
Three producing fields, located offshore Sabah in northern Borneo are currently being jointly considered Enhanced Oil Recovery (EOR). An initial screening study conducted in 2009/2010, indicated that a successful implementation of Alkali Surfactant Polymer (ASP) flooding might result in significant improvement in the ultimate recovery from the field.
Due to a limited experience with ASP flooding in offshore environment, a joint Shell and PETRONAS Carigali team was tasked to explore the entire solution space for this opportunity. This led to a development of 4 anchor cases, which span the expected key development decisions of injection strategy, injection rates, composition of the chemical cocktail, type of the host structure and location (onshore/offshore). The intent was to develop an understanding the trade offs between the project decisions with an ultimate objective to defining a series of building blocks and staircase to demonstrate technical feasibility and economical viability. The anchor cases are organized around the injection rate as the injection rate was assumed to be the key cost driver for the topside facilities at the outset of the study.
In the course of development and analysis of four anchor cases, a number of technical challenges emerged related to the choice of the water treatment scheme, power generation strategy and mechanical handling of chemicals in powder form. The technical challenges identified will require innovative solutions in the technology domain to enable a viable solution to the ASP flooding in the offshore environment.
This article presents an overview of the Area Development Plan study and shares a list of improvement opportunities.
Smoking, Not Human Papilloma Virus Infection, is a Risk Factor for Recurrence of Sinonasal Inverted Papilloma
Authors: Roh Hwan-Jung , Mun Sue Jean , Cho Kyu-Sup , Hong Sung-Lyong 
Published: March 2016

Background The recurrence rate of sinonasal inverted papillomas (SNIP) is 15–20%. However, few studies have investigated patient-dependent factors related to recurrence of SNIPs. Objective To analyze risk factors, including human papilloma virus (HPV) infection and smoking, as well as other factors, for recurrence of SNIPs. Methods Fifty-four patients who were diagnosed with SNIP and underwent surgery were enrolled: 39 men and 15 women, with the mean age of 54.0 years. Their mean follow-up was 40.6 months. Demographics and information about the history of smoking, previous surgery, tumor extent, follow-up, and recurrence were reviewed retrospectively. Those patients whose tumors were associated with malignant transformation were excluded in this study. HPV detection and genotyping in the tumor specimens were performed with the HPV DNA chip, a polymerase chain reaction-based DNA microarray system. Results Seven patients (13.0%) had recurrence, with a mean time to recurrence of 39.8 months. Recurrence rates in T1, T2, T3, and T4 of the Krouse staging system were 0% (0/4), 8.3% (2/24), 17.4% (4/23), and 33.3% (1/3), respectively (p > 0.5). Eight patients (14.8%) were positive for HPV DNA. All of these patients belonged to the group without recurrence (p > 0.5). However, recurrence rates according to HPV DNA positivity were not statistically different (0% versus 15.2%). Three (42.9%) in the group with recurrence and four (8.5%) in the group without recurrence were smokers (p < 0.5). Conclusion Smoking was associated with recurrence of SNIP. However, HPV infection is not a recurrence of SNIP risk factor.
Chronic Rhinosinusitis and Extraesophageal Reflux: Who is the Candidate for Antireflux Treatment?
Authors: Zeleník Karol , Formánek Martin , Matoušek Petr , Komínek Pavel 
Published: March 2016

Background During the past decade, extraesophageal reflux (EER) has been hypothesized to be one of the possible factors that contribute to the worsening of chronic rhinosinusitis (CRS). However, the relationship remains indeterminate due to its complexity, and it is not clear whether antireflux treatment is indicated for patients with recurrent CRS and who would benefit from it. Objective The aim of the study was to determine the severity of EER in patients with variable durations of CRS and different numbers of previous endoscopic endonasal surgeries (EES). Methods Ninety patients with CRS were recruited for the prospective case series. The age, sex, body mass index, reflux symptom index, duration of treatment of CRS with corticosteroids, and the number of ESS within the previous 5 years were ascertained. The severity of EER was evaluated by oropharyngeal pH monitoring by using the Restech system (the presence of EER, value of the RYAN score) and compared among the groups with varying durations of treatment of CRS (≤10 years, 11–20 years, >20 years) and different numbers of ESS within the previous 5 years (no ESS, 1–2 ESS, >2 ESS). Results Pathologic EER was present significantly more often in patients with CRS treated for >10 years (p = 0.0054) and in patients who underwent >2 ESS within the previous 5 years (p = 0.0001). Conclusion Patients with CRS treated for >10 years and those who had undergone >2 ESS within the previous 5 years had significant EER. Antireflux therapy (e.g., proton pump inhibitors) can be recommended for these patients. However, its effect has to be confirmed in further studies.
Mesoscopic Simulations on the Aggregate Behavior of Oligomeric Adamantane Surfactants in Aqueous Solutions
Authors: Chen Jingrui , Yang Chufen , Guo Jianwei , Zhu Dongyu , Fu Shuqin , Yang Zhe , Zhong Xing 
Published: March 2016

AbstractOligomeric adamantane surfactants are novel surfactants using rigid adamantane as spacer group, which can form a variety of scales and shapes of micelles and aggregates in aqueous solution. In this paper, the self-assembling aggregate behavior of N,N-dimethyl dodecyl ammonium bromide adamantine [Ad-(NC12Br)], 1,3-di(N,N-dimethyl dodecyl ammonium bromide) adamantine [Ad-(NC12Br)2] and 1,3,5-tri-(N,N-dimethyl dodecyl ammonium bromide) adamantine [Ad-(NC12Br)3] in aqueous solution is studied by mesoscopic simulations of dissipative particle dynamics (DPD). The simulation results show that the critical micelle concentrations of the three adamantane oligomeric surfactants is in the order of [Ad-(NC12Br)3] < [Ad-(NC12Br)2] < [Ad-(NC12Br)]. The three oligomeric adamantane surfactants are able to form aggregates with a variety of spatial structures, such as spherical micelles, vesicles, lamellas, reticular lamellas, column lamellas or steric reticules in response to different surfactant concentrations in the aqueous solution.
Synthesis and Evaluation of Some Phenol-Based Anionic Gemini Amphiphiles: Studying Their Influence in the Preparation of Cu2O nanoparticles
Authors: El-dib Fawzia I. , Mohamed Ammona S. , El-Sawy Abdallah A. , Mohamed Dalia E. , Abdelhalim Nermeen M. 
Published: March 2016

AbstractA series of phenol-based anionic gemini amphiphiles called α,ω-bis (m-dodecanoyl benzene sulfonate) with different spacers (C12-En-C12) where n = 1, 2, 3 has been synthesized via three steps of reaction: (1) acylation of phenol by dodecanoic acid using trifluromethane sulfonic acid as a catalyst, (2) tosylation of mono, di and triethylene glycol, then (3) coupling of tosylated ethylene glycols with acylated phenol, followed by sulphonation of the prepared compounds. The chemical structures of the prepared surfactants were confirmed using elementary analysis and different spectroscopic techniques including FTIR and 1H-NMR spectra. Also an evaluation of surface activity for the synthesized compounds has been determined including: surface and interfacial tension, foaming height, emulsification power, critical micelle concentration (CMC), effectiveness and efficiency. The prepared surfactants were used in the synthesis of cuprous oxide nanoparticles. The crystal structure, average particle size and morphology were investigated by X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM).
Experimental and numerical investigation on natural convection heat transfer in nanofluids
Authors: Nayak A. K. , Kulkarni P. P. , Chinchole A. S. , Mulye S. M. 
Published: March 2016

Abstract
An experimental study has been undertaken concerning natural convection heat transfer of nanofluids over a cylindrical heater with a constant wall heat flux condition. The cylindrical heater having 7.1 mm O. D. and 0.5 mm thickness with 100 mm heated length was used as heater surface. The heat flux was varied from 0 to 50 000 W/m2 and the corresponding Rayleigh number range is varied from 3 × 104 to 1.65 × 105. Different Nanofluids were used i. e. Aluminium oxide, Titanium dioxide, Silicon dioxide and Copper oxide with concentration varying from 0.0005 % to 0.05 % by weight. Results show that there was a reduction in natural convection heat transfer coefficient of nanofluids as compared to water. Experimental results were compared with existing models for similar geometry. However, the available correlation was found to be unable to predict experimental data as it does not take into account the effect of particle concentration. A new empirical model was developed based on the experimental data including the effect of nanoparticles concentration which predicts the experimental data satisfactorily.
Role of cerium, lanthanum, and strontium additions in an Al – Si – Mg (A356) alloy
Authors: Nabawy Ahmed M. , Samuel Agnes M. , Alkahtani Saleh A. , Abuhasel Khaled A. , Samuel Fawzy H. 
Published: March 2016

Abstract
The effects of individual and combined additions of cerium (Ce), lanthanum (La), and strontium (Sr) on the eutectic modification and solidification characteristics of an Al – Si – Mg (A356) aluminum alloy were investigated using optical microscopy and thermal analysis techniques. Addition of Ce, La, and Sr resulted in different depression levels of the eutectic nucleation temperature and eutectic growth undercooling, generating modified eutectic structures exhibiting different levels of modification. Microstructural results showed that the best modification levels using individual additions were achieved by Sr which produced a fine fibrous eutectic structure, followed by La, which produced a refined lamellar structure, with Ce providing the lowest level of modification. On the other hand, a combined addition of Ce and Sr provided the highest modification level, with the production of a very fine fibrous eutectic silicon structure. In general, the addition of Sr helped to further increase the refinement obtained in the alloys containing La or Ce + La additions. In the latter alloy, the main intermetallic phases observed were La(Al,Si)2 and Al20(La,Ce)Ti2Si. The improved modification levels were found to be proportional to the depression in the eutectic nucleation temperature and the eutectic growth undercooling. A high cooling rate also improved the modification level by at least one level.
Creep behaviour characterisation of a ferritic steel alloy based on the modified theta-projection data at an elevated temperature
Authors: Alipour Roozbeh , Nejad Ali Farokhi 
Published: March 2016

Abstract
This paper establishes and examines the constitutive model of the modified theta-projection concept for predicting the creep-rupture behaviour of a 2.25Cr-1Mo ferritic steel alloy foil at the loading conditions of practical interest. For this purpose, a series of creep-rupture tests are conducted on 0.15 mm thick foil specimens at an elevated temperature of 1 027 K and applied stresses in the range of 90 – 210 MPa. The creep-rupture behaviour of the foil is well represented using the model of the modified three-parameter theta-projection concept. Each model parameter is well represented as a function of the applied stress. Moreover, the creep failure mechanism was analysed by means of field emission scanning electron microscopy. The results showed that chromium atoms diffuse to the grain boundary and form carbide precipitates at the elevated temperature, leading to inter-granular fracture in the material.