bluuebunny/crossref_metadata_2025_split huggingface dataset:
Overcoming Limitations of Empirical Steady State Models using Multi Rate Testing, MRT
Authors: Ifechukwu Michaels , Adebowale Oladepo David 
Published: July 2015

Abstract
Gaslifted wells in mature fields have their peculiar characteristics that make them unique, like high water-cut, high GLR, and multiphase flow through the system. Such wells exist and it has being the tradition to model those using empirical steady state models. The objective of this work has been to determine if these empirical models are modeling the wells efficiently or not. Measured data, Multi-Rate Testing, MRT in form of gaslift injection rates and their corresponding liquid rates has been obtained and used as a basis for this research. If they do not model these wells satisfactorily, the project proceeds to determine the reasons and then recommend ways of overcoming these limitations.
The flow through the tubing is part of a system that starts with inflow from the reservoir. Empirical models developed under unique experimental conditions model multiphase flow from the bottom hole to the surface. These models, which include Beggs and Brill, Hagedorn and Brown, take into consideration several flow variables, which include liquid holdup, gas void, and flow regime to determine contributions of hydrostatic head, friction, and acceleration to pressure loss in the tubing. It was discovered that appreciable differences can exist in liquid rates calculated from these models and the measured liquid rates. This means the models are not efficient and the wells are not optimized.
Significant findings of this project are: the reasons for these deviations are centered on inherent flaws in these models. These models cannot capture the dynamic conditions of a gaslift well which produces liquid in slugs and some do not capture the effect of deviation on pressure gradient. Other reasons for deviation include the L-factor, productivity index, tubing inner diameter changes due to scale, roughness or oversized tubing, correlation model in use, and a combination of these factors. It is recommended that MRT be carried out more frequently.
A P/Z Plot For Estimating Original Gas in Place in a Geo-pressured Gas Reservoir By The Use of A Modified Material Balance Equation
Authors: Obielum I. O. , Giegbefumwen P. U. , Ogbeide P. O. 
Published: July 2015

Abstract
Geo-pressured gas reservoirs are reservoirs with high pressure gradient of about (0.5 – 1.0) psi/ft. The increase in pressures has been proposed by some authors to be caused by inability of excess fluids to leak-off after major tectonic events of compressional folding or rapid deposition of thick sediments in young sedimentary rocks.
The limitation of the conventional method in estimating original gas in place (OGIP) in a geo-pressured gas reservoir is that the solution gas in connate water is habitually neglected in estimating the OGIP. As a result, its contribution of the total gas production is omitted in the MBE. This leads to an inaccurate estimation of OGIP and gas reserve.
To eliminate this error, a new form of MBE is presented by this study. It includes the contribution of solution gas in connate water to the total gas production. A comprehensive compressibility term that includes the rock compressibility (Cf), water compressibility (Cw) and the gas solubility in water (Rsw) are introduced into the material balance equation and P/Z plots are formulated.
The result of the formulation indicates a 5 – 12% increase in the estimation of the OGIP as compared to some existing methods.
This tells the importance of the solubility of gas in brine in the estimation of the OGIP and the importance of its inclusion in the Material Balance Equation.
Benefit of Data Integration (Biostratigraphic Data) in Field Development –B4 Gas Reservoir Case Study
Authors: Ogbuli Andrew , Kakayor Omagbemi , Bahry Alia , Adepoju Yaqub , Awa Chukwunweike , Balogun Olalekan 
Published: July 2015

Abstract
The management of uncertainties associated with ‘green fields' remains a challenge due to data paucity. In the context of rising development costs for oil and gas projects, integration of data from all available sources becomes imperative. This integration has been demonstrated to reduce identified subsurface uncertainties and risks.
Biostratigraphic data which comprises use of forams and fauna from ditch cuttings picked in several reservoirs in the field has been evaluated and is used to delineate the sequence stratigraphic boundaries which have been shown to be useful for building the framework for field correlation, thus the building of realistic static models.
The CAMOY Gas field located onshore Niger Delta basin was discovered in 1961 by CAMO-1 well. To date, a total of six wells have been drilled in the field. The field is split into two fault blocks by CAMO fault (an East-west trending fault) in the south. The minor block is penetrated by just one well, with the remaining five wells in the main block. A total of nine hydrocarbon-bearing reservoirs have been penetrated occurring between the depths of 6500 ftss and 11000 ftss.
Key subsurface uncertainties that impact on the development plan of the B4 gas reservoir have been identified, and they are associated with structure and stratigraphy. A range of static volumes were computed initially based on the original understanding of the underlying structural and stratigraphic uncertainties. However, by integrating biostratigraphic data in the reservoir correlation, the uncertainty associated with stratigraphy is reduced, leading to a more realistic range of volumes.
Following the building of a realistic 3D model and volume ranges, two wells have been proposed to be drilled to develop the reservoir. The placement of one of the wells closer to the CAMO fault has been optimized post application of biostratigraphic data in B4 gas reservoir correlation.
The Analysis of String Stability Affected by Earthquake in the Shallow of Deep-water Drilling
Authors: Zhou Y. , Fan H. , Deng S. , Shen W. , Li W 
Published: July 2015

Abstract
The analysis of string stability affected by earthquake in the shallow of deepwater drilling
In deepwater drilling, wellhead, catheter, surface casing system and riser are linked together, they show the characteristic of instability under the influence of wave force. Some scholars have already done some research on this topic, however, the shallow sea is an area with frequent earthquake. Especially in some active seismic zone, oil and gas are often accompanied by earthquake, so it is crucially important to study the seismic forces on deep-water shallow wellhead, catheter and surface casing.
On account of the dynamic pile soil, the paper firstly studies the classification of the shallow soil properties. The paper carries on an overall study as landing depth of surface casing is about establishes the neural network model, considering the length, diameter, vertical pressure, casing pipe weight, soil properties, pore pressure, shallow properties of drilling fluid and especially the seismic characters of surface casing string. The influence of earthquake on the casing string stability will be gotten from these data collected after neural network analysis and calculation.
Based on the geological characteristics of Yingqiong basin, this paper establishes the neural network input and output bridge, obtains the earthquake effect on shallow casing string, and get the following conclusions: 1. Natural environment and other factors have certain effects on the casing string stability; 2. Traverse force on casing string increases by the earthquake action; 3. The earthquake has greater influence on the wellhead stability; 4. Shallow casing string vibration frequency can be obtained during earthquake action.
Study of Vibration of casing string in deep-water has been the difficulty of research. As many accidents happened due to multiple factors, shortages in current study, it is particularly important to research on how to build a deep shallow casing string vibration model, especially considering the uncertainty of seismic force. Importance of this paper is the further study of the influence of the seismic force.
Displacement Calculation of Dynamic Killing Drilling In Deepwater
Authors: Ren W. , Fan H. , Deng S. , Cui C. , Peng Q , Liu X. , Dou X. 
Published: July 2015

Abstract
The dynamic kill process is divided into two stages: “dynamic pressure stability” and “static pressure stability” stage in this paper. In dynamic pressure stability stage, sea water fluid was pumped into the well the initial killing fluid; Then in “static pressure stability” stage, pump into the weight liquid by quantified displacement based on “dynamic pressure stability” that can achieve complete killing effect, and control well kick effectively to drill efficiency.
In this paper, the multiphase multicomponent staged pressure control equation is established by considering the effect of shallow flow gas influx, meanwhile, it adopts the auxiliary equations such as velocity equation, density equation, and Herschel-Bulkley fluid rheological equation with yield value. The dynamical drilling tools flow pressure loss method is considered to improve the calculation accuracy of displacement. This paper solves the equation by the finite difference iterative method which should get the solution conditions firstly, then the initial and weight displacement are got.
This paper takes a deepwater well as an example by comparing and analyzing calculation results and the actual data which shows that it has a greater degree anastomosis with the actual construction site. The following conclusions are obtained: (1) Calculation accuracy is more precise and practical when using the Herschel-Bulkley rheological model and considering the dynamical drilling tools pressure loss calculation (2) The emphasis of finite difference iterative method are grid division and the boundary conditions determination. (3) The prevention of shallow geological disaster is more effective and the process is more delicate by dividing the progress into two stages.
With oil and gas area trend diverting from land to sea, from the superficial to deep, the drilling and mining condition is becoming more and more complex. The method proposed in this paper can not only solve the complex well kick in deepwater which can't be solved before, but also the multicomponent multiphase equation established make the control of shallow flow gas more subtly, and the calculation equations of high accuracy displacement built by stages make the kill process more systemic.
Alkaline-Surfactant-Polymer Flooding for Heavy Oil Recovery from Strongly Water Wet Cores Using Sodium Hydroxide, Lauryl Sulphate, Shell Enordet 0242, Gum Arabic and Xanthan Gum
Authors: Solomon Ujuanbi , Oluwaseun Taiwo , Olalekan Olafuyi 
Published: July 2015

Abstract
Among the world's natural sources of energy, petroleum stands out as the largest contributing mineral. This makes it the most sought-after mineral. Methods for oil recovery are constantly studied, and innovations are being made to improve the recovery of oil. Chemical Enhanced oil recovery (EOR) process is therefore at the fore-front of these studies and innovations.
The research work presents a comparative study of the core flooding carried out with different Alkali/Surfactant/Polymer (ASP) slugs formulated using sodium hydroxide (NaOH) an alkaline, surfactant being Lauryl Sulphate and Shell Enordet and polymer- gum Arabic and Xanthan gum.
The result shows that the ASP slug of Xanthan gum with Shell Enordet 0242 and Lauryl Sulphate had the highest displacement efficiency of 71.23% and 49.51% respectively. The others ASP slug formulated with gum Arabic and Shell Enordet or Lauryl Sulphate gave an efficiency of 31.36% and 32.20% respectively.
For heavy Oil recovery, the use of Shell Enordet 0242 or Lauryl Sulphate and Xanthan gum or gum Arabic will improve recovery. However, Xanthan gum gave a more stable displacement front than gum Arabic. Therefore, a higher concentration of gum Arabic is recommended for better recovery.
Utilizing Early Time Boundary-Dominated Flow Data to Make an Initial Estimate of Gas-in-Place: An Aid to Computing Material Balance Pseudotime
Authors: Damoah L. O. , Mohammed S. , Enty G. S. 
Published: July 2015

Abstract
We investigate, through a graphical representation of dimensionless pseudocumulative function, the possibility of using only the early time boundary-dominated flow (BDF) data to make an initial estimate of gas-in-place. In particular, we demonstrate that when viscosity-compressibility product ratio is plotted against fractional recovery on linear coordinates, an early straight line is observed during BDF regime. This phenomenon permits the dimensionless pseudocumulative function to be expressed as a quadratic function which, upon approximation, yields a linear function in terms of fractional recovery. This work thus demonstrates that the utilization of actual cumulative in gas flowing material balance yields two negative slopes − early time and late time BDF lines. As opposed to the late time BDF line, the early time BDF line yields a reasonable initial gas-in-place, and thus considerably reduces the number of time-consuming iterations associated with computing material balance pseudotime function. Perhaps, the significant finding of this work is that it establishes that the approximate gas flowing material balance equation is strictly applicable to the early time BDF data. Simulated and field data for both single- and multi-well systems are presented to demonstrate the applicability of the proposed approach.
Emulsion Treatment in the Oil Industry: A Case Study of Oredo Field Crude Oil Emulsion
Authors: Augustina Ovuema , Sylvester Okotie 
Published: July 2015

Abstract
The formation of emulsion is one of the challenges facing the oil and gas industry today. This is normally encountered when water is dispersed as fine droplets in the bulk of oil. This study presents the treatment techniques used by Nigeria Petroleum Development Company in Oredo field in breaking crude oil emulsion. Wells 2L and 4L were used for the analysis. Crude samples were obtained at the upstream of chemical injection points to ensure the samples were true representatives of the crude from the wells in the field. Chemical demulsifiers (DM1, DM3, DM4, and DM5) were formulated in the laboratory which was used in the treatment of 100ml of emulsion. Results show that DM3 and DM5 were the most effective chemical demulsifiers formulated in the laboratory for Oredo wells 2L and 4L respectively and also, temperature is an indispensable determining factor in the treatment of emulsion.
Hydrocarbon Resource Development Decision for Gas Reservoir with 10ft Oil Rim: Niger Delta Case Study
Authors: Balogun Olalekan , Adepoju Yaqub , Ogbuli Andrew , Chukwunweike Awa 
Published: July 2015

Abstract
The presence of oil rim in gas reservoirs could potentially have an impact on the timing and philosophy of gas development in the field. Sound reservoir management strategy requires investigation of the development feasibility of the oil rim as part of the field development planning study. This is also a prerequisite to securing regulatory approval for the resulting field development plan.
Eleju C1000 reservoir contains a proven 10ft oil rim with a huge gascap supported by clearly logged fluid contacts. The field is located onshore Niger Delta, with six well penetrations, leading to the discovery of nine hydrocarbon-bearing sands. The field development concept is based on the gas resource in C1000 reservoir, which holds over 80% of the estimated field gas in-place volume.
Based on the available geoscience and engineering data, analytical and simulation methods were employed to evaluate the feasibility of developing the 10ft oil rim in C1000 reservoir. The operator's Oil Rim Development Guidelines and Wyne et al Matrix (for evaluating oil reservoir feasible concept) were employed in selecting an optimum development concept for the C1000 reservoir.
Analytical and simulation methods resulted in C1000 estimated EUR per well range of 0.3 – 0.4 MMstb with a unit development cost (UDC) of about $100/bbl excluding flowlines and facility. This is not economically favourable to the project which has a UDC of $3.4 per boe for gas development only. Therefore, the optimum development option for reservoir C1000 is gas development only.
Design of a Coordinates Aware Remote Module for Effective Oil and Gas Pipeline Monitoring Using GPRS, GPS and Google Maps on Android Devices
Authors: Ileanwa Ocheja Patrick , Ngozi Ezeanyagu Obianuju , Chigozie Udeh Paschal , Eyo Abu Abu 
Published: July 2015

Abstract
The incessant and malicious damage of oil and gas pipeline has continued to impose more challenges on production, transportation and utilization of oil and gas resources. This menace has led to loss of lives and properties, environmental pollution and degradation as well as adversely affected the economy of some countries negatively. With industry professionals rising to the occasion, electronic systems remain one of the potential technologies to be considered. This paper aims at addressing security challenges faced by oil and gas industries with greater emphasis on oil and gas pipeline security. It also unveils a design of an intelligent security system capable of detecting and tracking intruders within a specified perimeter and also real time transfer of data from such locations of security breach to remote devices. Data collation on location is achieved using GPS and Google Maps API enhanced to accurately locate the routes of pipelines. Security breach is detected through the use of sensor networks and consequent real-time communication to a mobile application is realized through a GPRS module and Android operating system. This work presents an opportunity for existing and emerging economies to combat oil and gas theft which maximizes profit.
Optimality Test of Marginal Field Development Financing Arrangements in Nigeria
Authors: Ekeh Chibueze , Asekomeh Ayodele 
Published: July 2015

Abstract
Marginal oil fields in Nigeria, some of which the International Oil Companies (IOCs) have abandoned for over 10 years previously, are now being awarded to indigenous oil companies. Due to difficulty with raising development finance domestically, some of the indigenous Marginal Field Operators (MFOs) have resorted to allowing foreign-listed Financial Partners (FP) to ‘carry’ their share of development costs. We test the optimality of such ‘carried’ cost arrangements by using the discounted cash flow method to analyse the economic viability of two model marginal fields (one onshore and the other offshore) in the Niger Delta/Gulf of Guinea region. Four different scenarios (sole risk [MFO], sole risk [FP], joint venture without carry, and joint venture with carry) for each model are compared. The empirical results appear to imply that marginal field operators are better off if they can contribute their share of development costs, by equally sourced debt and equity financing domestically, than when they are carried by a foreign financial partner. The computed net present value (NPV), NPV per barrel, modified internal rate of return (MIRR) and payback period all show that carrying of interest favours the FP over the MFO in a joint venture arrangement. Additionally, oil price and Petroleum Profit Tax (PPT) have the greatest impact on NPV in both models.
Development of Cost Effective Surfactants from Local Materials for Enhanced Oil Recovery
Authors: Adeniyi A. T , Onyekonwu M. O , Olafuyi O. A , Sonibare L.O. O 
Published: July 2015

Abstract
Surfactants are used to lower surface/interfacial tension in crude oil reservoir, and hence increase oil mobility. Niger Delta Oilfields are matured and may be said to be characterized with heavy hydrocarbons. The heaviness is a result of years of associated gas flaring; leaving behind only oil. It is imperative to inject surfactants to mobilize oil column through flooding. Unique local raw materials have been identified and developed to form Ibile Surfacs. Ibile Surfacs is biodegradable, easy to formulate and readily available as oilfield chemicals. Three branded market samples of surfactants were collected for comparative studies, with the Ibile Surfacs. Branded market samples obtained are Tween 80, Lauryl Sulphate, and Teepol. Some of the test conducted for the samples are stability under similar temperature values, environmental biodegradability, ability to foam and sustain foaminess with saline water and hard water respectively. The result obtained for biodegradability shows that, the Ibile Surfac maintain reasonable leads ahead of Lauryl Sulphate and Teepol and similar characteristics with Tween 80. Results obtained for stability under the same temperature values, reflected equal trends for Tween 80, Lauryl Sulphate, and Teepol with Ibile Surfacs showing a lead. Similarly, a table of results tabulated for foamability and foaminess sustainability gave strong indications that Ibile Surfacs foamed continuously in hard water. Whereas, Tween 80, Lauryl Sulphate, and Teepol broke down at moderates water hardness. It can be safely stated that, Ibile Surfacs is better than trio of sampled market brands, and can be use to replace either Tween 80 or Lauryl Sulphate, and/or Teepol.
An Application of an Expert Method for M-28 Aircraft Maintenance Support / Zastosowanie Metody Ekspertowej Do Wspomagania Eksploatacji Samolotu M-28
Authors: Golański Piotr 
Published: July 2015

Abstract
A concept of an expert system that can be used for supporting aircraft diagnostic and maintenance processes is presented in the paper. The paper discusses general principles of an expert system creation as well as main tools used for implementation of such a system. A method of application of one of those tools - CLIPS expert system shell, for solving M-28 aircraft maintenance problems is presented in the paper.
Jet Fuels Degradation under Severe Thermal Loads / Degradacja Paliw Lotniczych W Warunkach Wysokich Temperatur
Authors: Sarnecki Jarosław 
Published: July 2015

Abstract
Paper presents research results of jet fuels thermal degradation exposed to different thermal loads. This problem is especially important as it influences safety of aircraft operation. Jet fuel in modern engines is used in heat transfer and cooling of different construction elements. Together with new engines’ construction and materials used thermal loads affecting jet fuel become more severe, and thus in aircraft fuel system not well understood phenomena occur, resulting with plugging injectors, valves and affecting elastomers. They affect engine operation and should be well and carefully described and understood to prevent them. Research results presented here are the first data in Poland dealing with jet fuels’ thermal degradation problem. Article is aimed to present the mechanism of jet fuel thermal degradation under different temperatures. The project has been funded by National Science Centre granted with decision no. DEC-2011/01/D/ST8/06567.
Possibilities Concerning Diagnosis of the SSP-FK Aircraft Fire Suppression System in Terms of Determination of Reasons for False Fire Alarms / Możliwości Diagnozowania Lotniczego Systemu Przeciwpożarowego Ssp-Fk W Aspekcie Określania Przyczyn Fałszywego Sygnalizowania Pożaru
Authors: Szelmanowski Andrzej , Borowski Jerzy , Głyda Krzysztof 
Published: July 2015

Abstract
The paper presents selected results of work at the Air Force Institute of Technology (AFIT) in the scope of testing of the SSP-FK fire suppression system used on many types of military aircraft operating in the Polish Armed Forces. For the purpose of determining conditions for false fire alarms, SSP-FK simulation models have been developed. The study was carried out on simulation models in Matlab-Simulink and Circuit-Maker packages. Results of this work have been used for diagnosis of the SSP-FK system during a test of real cases of false activation of these devices.