bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Wax Precipitation Tendency Using Sara Analysis
Authors: Mmata Bella , Ajienka Joseph , Onyekonwu Mike , Chukwu Godwin 
Published: July 2017

Abstract
Separation of crude oil into hydrocarbon fractions such as saturate, aromatic, resin and asphaltene (SARA) fractions is needed in order to obtain the concentration of each group. This chemical analysis of crude oil is necessary for upstream, midstream and downstream operations; as it yields information such as crude oil stability (asphaltenic stability), fouling propensity and the blending compatibility of the crude oil. Since SARA analysis can give information on asphaltenic stability, there is need to investigate the use of this analysis for wax precipitation tendency or wax instability.
In this work, thirteen samples collected from three different fields in the Niger Delta region were studied. The modified ASTM D2549–02 was employed to separate the crude oil samples into their various chemical species. Wax Appearance Temperature (WAT), pour point and wax content were measured on the samples as well to determine whether they were waxy crude oils or non-waxy crude oils.
Out of the thirteen samples studied, seven were confirmed waxy samples while six were non-waxy from the WAT, pour point and wax content measurements. The SARA analysis carried out on twelve of the samples on the other hand, showed the samples had a high percentage of saturates ranging from 40.97 wt% to 67.60 wt%. Samples C11 and C12 which were non-waxy crude oils even had saturates of 62.56% and 55.56% respectively. Thus, SARA analysis data on its own might not be a tool to distinguish waxy crude oils from non-waxy crude oils.
Investigating the Application of Radial Drilling Technique for Improved Recovery in Mature Niger Delta Oil Fields
Authors: Ibeh Stanley , Obah Boniface , Chibueze Samuel 
Published: July 2017

Abstract
Radial drilling (RD) technique utilizes hydraulic energy to create several lateral holes in different directions and levels with several lengths. These lateral holes are made by milling the casing with small bit then extending these holes laterally using high pressure hydraulic jetting. Successful case histories of radial drilling technique in some part of the world were discussed. The candidate recognition for proper well selection which is the key for successful application of this technology was carefully examined. Some Niger Delta reservoir geological and mechanical parameters were collected and thoroughly screened to identify the possibility of increasing the well potentials of mature/brown fields using radial drilling technique.
In this paper emphasis has been given to study the process of radial drilling technology, its advantages, overcoming its limitation, its usage in the recovery of left out crude oil from existing reservoirs especially those from brown fields. The paper also provides ways to implement RD to such oil fields before implementing the expensive IOR-EOR methods and also an analysis of its economic feasibility is discussed. The Nigerian prospects of Radial Drilling technique has also been analysed and recommendations has been given based upon the possibility of implementing in the brown/ depleted fields of Nigeria.
Pressure Transient Analysis of Data from Permanent Downhole Gauge PDG: Case Studies from Offshore Nigeria
Authors: Zubarev Denis , Nagaraj Guru Prasad , Okoli Fanyama , Deshpande Vaibhav 
Published: July 2017

Abstract
Historically the pioneers in Permanent Downhole Gauge (PDG) deployment were large operators targeting real time reservoir surveillance on a few high profile wells or field development projects. With time, utilization of PDG became an industry standard, unit prices went down and reliability has significantly increased, making application of PDGs a wide spread phenomenon.
The interest in PDG data goes beyond simply recording pressure and temperature at any given time for reservoir surveillance and monitoring. The combination of the well production and PDG acquired pressure data proves to be an ideal dataset for reservoir characterization and improved production optimization.
This paper presents a dynamic real-time well testing workflow used in analyzing PDG data for Pressure Transient Analysis on a complex reservoir geometry offshore Nigeria. It discusses the extent and applicability of Pressure Transient Analysis (PTA) using Permanent Downhole Gauge data for complex reservoir and well performance characterization.
In analyzing such PDG data, it was important to correctly identify anomalies which could hamper the interpretation of the complex dataset, such as tidal effects. The presence of these anomalies can significantly impact data analysis, resulting in wrong flow regimes identification and erroneous well and reservoir parameters estimation. Therefore, tidal signal and other noises had to be identified and removed from the pressure data before the interpretation.
Commercially available software was used for de-noising and managing the real-time measurements, as well as modeling and analysis of the test data. Actual real-time pressure from PDG and production data from surface well test measurements were used in the analysis to determine reservoir parameters and evaluate well performance. This paper elaborates on the proper techniques for data handling of offshore acquired PDG measurements for Pressure Transient Analysis. The workflow resulted in significant cost savings due to a reduction in the number of shut-ins planned consequently.
Debottlenecking XYZ Flowstation to Increase Capacity and Optimize Performance
Authors: Nwosu Dixon , Bamisebi Adetiloye , Eleazu Goodluck 
Published: July 2017

Abstract
The XYZ field has a single-train two-stage separation facility consisting of a 3-phase test separator, a 3-phase HP separator, and a 3-phase LP separator. The reservoirs are of volatile-oil/condensate type, producing with comparatively high GOR and high FTHP. Its current production potential is 6,200bopd and a 35MMscfd, increasing steadily to a peak of 26,000bopd and 98MMscfd by 2022. Thus, in view of this anticipated increase in field production, it is expedient to assess the capacity and performance of the station, identifying bottlenecks that need to be addressed as well as defining requirements for the field's further development programme. Process simulation models, based on the facility's existing configuration and the proposed configuration, were developed with Aspen Hysys v7 using the Peng-Robinson fluid package. API 12J and API 14E criterion were then employed to determine the fluid handling capacity of the vessels and the sizing adequacy of the process lines respectively.
Results showed that the flow-station, which can handle the current field production albeit a minor restriction by the HP Flare KO Vessel outlet line and flare line, cannot handle the forecast production beyond 2016 owing mainly to limitations in the HP separator gas handling, under-sized process lines and an ultimate restriction from the LP separator oil outlet line. With peak production of 26,000 bopd, the station needs to be upgraded and debottlenecked by installing an XHP separator, as well as replacing identified under-sized lines, to resolve the identified constraints. The XHP separator, which constitutes an additional separation stage, will enhance liquid recovery amounting to 500bopd starting from 2019, decrease waste associated gas production and conserve off-separator gas pressure.
Obtaining BHP Data Via CITHP Extrapolation in an Economically and Security Challenging Environment
Authors: Korubo Waazor , Olugbenga Daodu , Nnadi Magnus , Tunji Bakare , Emelle Chima , Nwankwo Cosmas 
Published: July 2017

Abstract
Acquisition of bottom hole pressure is a statutory requirement in Nigeria. In addition, pressure data provide a better understanding of reservoir responses to production for effective wells, reservoirs and facilities management. The data is used to calibrate dynamic and well models in order to improve the quality and reliability of predictions that feed into Annual Review of Petroleum Resources (ARPR) cycle. Despite its importance in the oil and gas industry, there are often delays in mobilizing for Bottom Hole Pressure Data acquisition due to deferment concerns, budget constraints and security challenges. This was the case with some gas wells in Aowa field in the Niger Delta region of Nigeria where the bottom hole data could not be acquired on scheduled to support the technical evaluation of resources within the given timeframe of the annual volumes reporting cycle. This paper is a case study on the determination of closed in bottom hole pressure (CIBHP) from Closed in Tubing Head pressure (CITHP) during well shut in periods using the Cullender & Smith methodology. The proposed approach involves derivation of bottom hole pressure data from measured closed in tubing head pressure and known gas gradient.
The scope of implementation covered three gas wells in the Aowa field (AOWA 3, 4 & 5) that supply gas to NLNG and processed through a Central Processing Facility (CPF). The three gas wells are produced from three different reservoirs in the field with total expected gas rate of about 350 MMscf/d. These wells are significant to achieving the export nomination expected from the CPF. These wells came onstream in July 2013 and have produced as expected.
The novelty of this approach is the elimination of HSSE risks associated with undue staff exposure in the field, obtaining fit for purpose quality data without production deferment and costing down OPEX as ca. US$22,500 per well can be saved due to non-contractor engagement. The work flow established by this method can be applied across other operating units for gas wells having similar operation challenges.
The results obtained from this methodology compared favorably with actual measurement carried out later in the wells with the highest deviation of &lt; 5%. The study revealed that the accuracy of the result using this approach is highly dependent on gas gradient.
A Realistic Kick Simulator for Casing Design-Part 1
Authors: Michael Ohaegbulam Chukwudi , Ugochukwu Ibeh Stanley , Boniface Obah , Chibunma Amaefule , Stephen Nnakaihe 
Published: July 2017

Abstract
Casing design an integral part of the well planning is divided into two phases: determination of the optimum casing depth and selection of appropriate casing grade. Conventionally, casing depth is determined using pore-fracture pressure data and an arbitrary kick margin (0.5ppg). This method maybe uneconomical or pose a well control risk since the kick margin may not reflect the actual well condition during fluid influx and subsequent circulation. A gas kick simulator is proposed in this work to aid the drilling engineer to make a good engineering decision during the well planning stage and rig-site well control operation. The kick simulator is derived using the using continuity equation, equation of state, and kick tolerance concept. The effects of temperature, fluid compressibility, annular friction pressure loss, choke line friction pressure loss, gas migration, variable fluid density and two-phase flow are incorporated in the the model. Beggs and Brill correlation is used to describe flow in the two-pase region; while frictional effects in the single-phase region and gas compressibility are modeled using Power Law Model and Peng-Robinson equation of state respectively. The effect of gas migration is modeled using Harmathy, Taylors and Zuber et al bubble rise velocity models. To account for liquid hold up, three types of flow regimes are adopted in the model: single gas bubble, mist and intermittent/transition flow. The results from the simulation study show that determining casing depth using pore-fracture data and an arbitrary kick margin may result to well control incident. Neglecting the effects of temperature, fluid compressibility and use of single gas bubble model is unrealistic and will require deeper casing depth. In offshore wells, choke line friction loss is an important factor that should be considered during the well planning stage.
Managing Reservoir and Operational Decline without a Rig: An Okan Case Study
Authors: Ogbuagu Frank , Afolayan Femi , Esan Femi , Obot Nsitie 
Published: July 2017

Abstract
The objective of this paper is to share learnings from the Okan field, highlighting successful strategies adopted to mitigate reservoir and operational decline almost 8 years without producer drilling or major rig workovers. Value gained is quantified to show that over a third of the current Okan production is tied to strategies adopted during the period of interest.
Details of the different wellwork methodologies are provided to communicate how value was maximized using minimal cost. Key strategies adopted that have created the Okan success story over the period of interest include the jacket-centric rigless wellwork approach which has resulted in a drop in overall wellwork costs as multiple wells on the same jacket are worked over in one mobilization. The use of interwell gas lift systems for isolated jackets unlocked reserves that would otherwise be uneconomic because of costly pipelay. In addition to enhancing production from wells requiring gas lift, the conversion of idle oil line conversions to gas supply lines for gas lift ensured available facility assets are utilized, bringing pipelay savings as well as production gain. Also, taking full advantage of the Okan Gas Gathering and Compression Platform, production from reservoirs with high GOR has been optimized, resulting in oil and gas gain without routine gas flaring. Challenges encountered and lessons learned are also shared in this paper.
As a result of the strategies shared in this paper, the current Okan production is over 30% higher than what it would have been without the deployment of these strategies highlighted. The same strategies can be transferred to other assets to obtain optimum value in these times of low commodity prices.
Displacement Efficiency in a Deep Water Turbidite Field in Gulf of Guinea
Authors: Itua Osazua J. 
Published: July 2017

Abstract
In Deep Water (DW) turbidite reservoirs in the Gulf of Guinea (GoG), waterflooding is deployed to maintain reservoir pressure and improve hydrocarbon recovery. The overall recovery from a reservoir under waterflooding is the product of displacement efficiency (DE), which is a function of remaining oil saturation (ROS) of the swept region, the vertical efficiency, and the pattern efficiency.
Analysis of open hole logs from recent infill wells in the Eko field that penetrated swept intervals provided useful insight into in-situ ROS values. The found ROS of between 0.05 to 0.11 were significantly lower than the 0.2 observed from core. The resulting DE of 87% estimated on the basis of the ROS data across these swept intervals has the potential to significantly improve economic robustness of some DW projects if proven correct.
AskWells - A Way to Improve Well Delivery Performance Via Knowledge Archiving and Transfer
Authors: Majekodunmi Ayodeji A. , Ibeku Charles , Nnadozie Eze 
Published: July 2017

Abstract
Efficient knowledge utilization is crucial for organizations to remain competitive. Recent changes and challenges facing the global oil and gas industry require companies to improve operational efficiency by effectively capturing and transmitting knowledge across their organizations. This is currently done using various knowledge management tools and processes. Challenges such as poor data repository platform integration, database queriability and Graphic User Interphase ineffectiveness reduce knowledge management efficiency.
In line with on-going continuous improvement initiatives, the Wells Performance Team initiated a project to optimize its knowledge management process. The impact of recent changes including portfolio divestments, experienced personnel turnover and job role changes on knowledge archiving and transfer were identified. The limitations of existing platforms were also analysed and target solutions were designed.
These resulted in the creation of a tool – AskWells. AskWells is a search tool that queries existing knowledge databases to generate information required to respond to operational challenges based on learnings from historical experiences and recommendations from best practices. It is also a tool for documenting and cascading Learnings from Incidents, Investigations, After Action Reviews and Best Practices. The deployment of AskWells coupled with a review of the people process around data management led to an improvement in the business’ ability to document operational learnings for effective retrieval and cascade. The ability to identify historical challenges to similar well delivery operations and narrow down search results to similar case conditions have taken an upward notch, thus improving well delivery performance remarkably. Learnings from other work units and teams within the organization are also effectively accessible with AskWells.
Overall, AskWells has contributed to an improvement in well delivery performance while deepening integration and collaboration with stakeholders. This paper discusses the AskWells tool in detail, bringing to light various aspects considered during tool development, and the success stories post deployment.
Production of Biolubricant From Castor Oil
Authors: Dibal Ibrahim N. , Okonkwo Paul C. , Haruna Ibrahim 
Published: July 2017

Abstract
In this research, bio-lubricant was produced from castor oil in two stage processes where methyl ester of the oil was produced by esterification and then transesterified using homogenous catalyst (NaOH). It was then blended with 15w/w% of Sodium Lauryl Sulphate (SLS) to produce bio-lubricant. By varying the amount of homogenous catalyst (1.0-1.2 w/w %), three (3) different grades of bio-lubricant samples were produced and subjected to physical and chemical test to determine their characteristics. The three grades of the bio-lubricant samples weighs 88.76g, 125.23g and 162.61g respectively with varying degrees of kinematic viscosity of 89.68, 67.24 and 58.01cst respectively at 40°C, and 8.14, 7.92 and 7.59cst respectively at 100°C. The viscosity indexes of the three samples are; 32, 78 and 91, pour points are −21, −18 and −18°C, and the flash points are 215, 211 and 223°C respectively for each of the samples. The properties of the biolubricant samples indicates that they can be used under wide range temperatures. Our results are comparable with mineral based lubricant standards of Motorlube (SAE 20W40).
Maximizing Opportunities in The Gas Sector by Using Existing Wells and a Fast-Track Development Approach: The Zeta Field Case Study
Authors: Azubike Obi , Wood Mark , Benyeogor Ogochukwu , Usman Ismail 
Published: July 2017

Abstract
The maturation and development of gas resources has of recent been on the front burner for many Oil & Gas producing countries and companies, mainly due to the drive for more environment friendly fuel and increasing demand for natural gas as a key driver for industrialization and growth. In Nigeria, the situation is not different, with proven reserves of 180 Tcf, but very low figures in production and utilisation of its gas resources, there has been an increased focus and push towards increased development in the natural gas sector.
From the inception of oil and gas exploration in the late 1950’s to late 1990’s, most of the focus in the Nigerian Oil and Gas industry has been towards oil development, with little or no focus on gas, which led to the suspension of many exploratory/appraisal gas discoveries in several fields, with no plans of further development.
The Zeta field is located in the Niger Delta region of Nigeria, with predominantly gas bearing reservoirs. Together with other nearby fields, it has about 9 Tcf of discovered GIIP. There is no existing infrastructure to process or evacuate the gas. Zeta field currently has four exploration and appraisal wells drilled between 1973 and 1987 and encountered 13 stacked reservoirs with a total expectation GIIP of about 2 Tcf and CIIP of about 100 MMstb.
This paper highlights how opportunities in the gas sector has been maximized by deploying an innovative commercial and technical solution to unlock gas resources from a cluster of fields with large gas resource but not close to any evacuation facility. It shows how the existing exploration/appraisal wells has been planned for re-entry and side-track, to ensure a fast-tracked development of five Ready-To-Go (with no technically exploitable oil rim) reservoirs in the field. It also highlights how scalable reservoir models have been used in the development of the five reservoirs ensuring that the target onstream date is met.
La competencia para aprender en programas de Educación de cuatro universidades colombianas
Authors: Jerónimo-Arango Lida Cruz , Yaniz Concepción 
Published: July 2017

La competencia para aprender se constituye en una de las bases más importantes de la educación del siglo XXI. Objetivo: comparar el nivel de competencia para aprender en estudiantes que inician y finalizan programas de grado y posgrado en Educación en cuatro universidades colombianas. Método: investigación con alcance descriptivo de corte cuantitativo. Se utilizó un muestreo no probabilístico de oportunidad en el que participaron 581 estudiantes matriculados en primer y último semestre de grado y posgrado en Educación a quienes se aplicó la Escala de Competencia de Aprendizaje (LCS). Los datos fueron analizados con el paquete estadístico SPSS versión 23. Resultados: muestran diferencias significativas entre los estudiantes de primer semestre de pregrado y los estudiantes de último semestre de posgrado, y no así en los estudiantes que finalizan su formación de pregrado. Conclusión: la escala de competencia para aprender es un instrumento válido para medir el desarrollo de dicha competencia en la población estudiada. El desarrollo limitado de la competencia para aprender puede deberse a que es posible que en los primeros años de formación, los estudiantes participantes en este estudio desconocen la existencia de esta competencia y antes no experimentaron qué significa obtenerla, por consecuencia, la asumen como adquirida. © Revista Colombiana de Ciencias Sociales.
La imagen de Gustavo Rojas Pinilla en la propaganda política durante la dictadura militar, Colombia 1953-1957
Authors: García-Villamarín Ana Lucía 
Published: July 2017

Objetivo: analizar el uso que tuvo la imagen de Gustavo Rojas Pinilla como propaganda de su régimen durante el periodo que duró su dictadura: 13 de junio de 1953 a 10 de mayo de 1957. Método: cualitativo desde la estrategia documental (archivo, prensa y publicaciones oficiales). Se seleccionaron imágenes de Gustavo Rojas Pinilla, que hubiesen sido producidas o divulgadas en el periodo estudiado, las cuales fueron descritas, analizadas e interpretadas. Resultados: desde el inicio de la dictadura, Gustavo Rojas Pinilla utilizó su imagen como propaganda del régimen para crear un consenso popular por medio de alusiones de paz y progreso, constituyendo una iconografía populista que empleó intencionalmente referencias a Simón Bolívar y Cristo. La estrategia fue encaminada desde la Oficina de Información y Propaganda del Estado (ODIPE) en Colombia, y apoyada de cierta manera por la Hamilton Wright Organization en el ámbito internacional. Conclusiones: si bien la circulación de su imagen se dio de manera impuesta, su uso como propaganda política en la dictadura funcionó acertadamente en ese momento, pues fue diseñada para impactar a varios sectores de la sociedad que en su mayoría eran analfabetas. © Revista Colombiana de Ciencias Sociales.