bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the Effectiveness of Ergonomics Practices in Selected Workplaces in Port Harcourt, Nigeria
Authors: Okoye Esther Amaka , Ugbebor John , Adaramola Samson 
Published: October 2018

Abstract
The study was carried out to determine the level of ergonomics awareness and the level of implementation/practice of ergonomics is selected workplaces in Port Harcourt. Ergonomics should be major emphasis at the workplace in designing of task to fit to the workers capabilities. Problems associated with major activities include extreme temperatures, noise, slippery surfaces, manual handling, exposures of carrying, lifting, lowering, forceful pushing and heavy pulling of tasks leading to occupational diseases. Collections of primary data were by means of questionnaires administration to 150 persons, amongst the number distributed 120 questionnaires were retrieved. 42 from Exploration and Production, 38 from Oil and Gas Servicing, and 40 from manufacturing industry representing a response rate of 80%. 20 questions were designed as questionnaire parameters; the first 10 are to assess the level of ergonomics awareness amongst workers in 3 selected workplaces in Port Harcourt, while the second 10 are to evaluate the ergonomics implementation/practice in three selected workplaces in Port Harcourt. The responses are rated strongly agree (4), agree (3), disagree (2) and strongly disagree (1). The approach was necessary to facilitate the evaluation of Kendall's coefficient of concordance (W), that is, the degree of agreement amongst the respondents. The results revealed on the average, an appreciable level (75%) of awareness and (53%) level of ergonomics implementation/practice amongst the respondents, respectively. Lack of awareness on static loading as a risk factor in ergonomics, non-availability of good fitting thermal gloves to help with cold conditions, noisy machines not being isolated, non-availability of lumbar support chairs (adjustable task chairs), and finally, not conducting health examination surveillance on workers periodically are the gaps identified. Kendall's analysis revealed a high degree of agreement amongst the respondents on both ergonomics awareness (0.74) and ergonomics implementation/practice (0.99), respectively. Thus, the study recommends more ergonomics trainings on workers, provision of lumbar cushions, isolation of noisy machines, provision of good fitting thermal gloves and periodic health examinations on workers.
Optimum Well Type for Oil Rim Reservoirs with Large Gas-Cap and Strong Aquifer
Authors: Ogiriki Shadrach O. , Imonike George O. , Ogolo Naomi O. , Onyekonwu Mike O. 
Published: October 2018

Abstract
Oil rim reservoirs are often troublesome to produce commercially as a result of the adverse effect of coning and cusping/cresting. In this study, deviated and horizontal wells were employed to determine the optimal well type to be drilled in the "GISO" oil rim reservoir in order to attain optimum oil recovery while reducing uneccessary cost. The GISO oil rim reservoir considered in this study had a thickness of 8ft with grid dimensions of 91×74×20 in the i, j, and k coordinates respectively, and contained a dynamic reservoir oil volume of 9.37MMSTB. Results obtained from simulation revealed that there was not enough oil recovered from the subject oil rim reservoir, owing to the fact that that the reservoir had a very small oil column thickness and this led to the early encroachment of water into the oil column. Three horizontal wells and one deviated well were simulated in the oil rim in order to determine the preferred well type for optimum hydrocarbon recovery for a period of 20 years. The four cases were simulated with a constant production rate of 2000STB/D. Well H1, a horizontal well with lateral length of 272ft recovered 840MSTB, while well H4, a deviated well with a deviated well case with an inclination angle of 84.20° from the GOC and lateral length of 242ft recovered 830MSTB.
Results-Oriented Land Asset Management Using Numerical Model
Authors: Okpo Ekpenyong E. , Onyekonwu Mike 
Published: October 2018

Abstract
The Oil and Gas industry is a melting pot for assets and technology and thus requires an ingenious management of the duo to achieve sustained goal of reduced operational cost and maximized profits. Incidents on typical land assets like pipeline located on acquired or leased areas have been known to cause companies a lot, including huge litigation payments, downtime, damaged public image and even threat of business closure. Studies indicate that various tools are currently being used to manage land assets, including third party solutions, spreadsheets, homegrown software solutions and database software. A comparative study was carried out using the Crystal Ball and OptQuest excel add in to determine an effective solution that will maximize Total Economic Value Added (EVA).
The result shows that the choice made is a one-time decision; each solution will either be successful or not. If a project is not successful, the company runs the risk of incurring the loss of the initial investment and maybe even its faith in that project. Thus, the goal is to incorporate risk analysis within the context of the project selection, and to select the best projects that satisfy input constraints while optimizing the EVA
Benchmarking and Prediction of Ultimate Recovery Based on Performance Data of a Mature Brown Field: A Case Study From Deepwater Nigeria SPE- Paper Id 130
Authors: Oshomah Hakeem , Ghosh Ankush , Awasthi Amit , Njoku Chukwueke , Olatunji Idris , Hafiz-Ringim Mohammed 
Published: October 2018

Abstract
Eko is a prolific Deepwater brown field on production for 10+ years and cumulatively produced ~750MMSTB from 30+ producers and 25+ injectors (average cumulative production 25MMSTB/well). However, the actual ultimate recovery developed by producers vary from &lt;10MMSTB to &gt;90MMSTB which can be attributed to STOIIP distribution, reservoir complexity & development strategy. As the field has matured to production plateau and with sufficient static & dynamic data now available, a Deepwater Analogue study was kicked off to develop an Ultimate Recovery(UR) predictive model to benchmark the robustness of the simulation predictions for the next phase of in-fill development wells. This database will also support the quick evaluation of other Deepwater fields which are in advance stages of hydrocarbon maturation funnel. An integrated study was carried out to collate all static/dynamic data in each reservoir/well. Drainage area for each producer(s)-injector(s) well pair was defined (Figure 1) and associated average reservoir properties were estimated from latest history matched models. Several combinations of parameters were cross-plotted against the objective function (UR/Well) and a proxy function was established to predict UR for future wells. An error analysis was carried out on the reference case function to establish prediction uncertainty ranges. The simulation based P90/P50/P10 UR ranges for the future in-fill development wells were compared with this analogue database and where the forecasts from models were not in sync with actual observations in Eko field, modeling assumptions were revisited. As way forward, this analogue database will be updated with new well information, static re-modeling and/or history matching exercise. Also, the in-fill well results will be used as litmus test for the robustness of the analogue model.
Figure-1 Amplitude Map Showing Definition of Drainage Areas for Major Reservoir (Red wells = Oil Producers, Blue wells =Water Injectors)
Effect of Pipe Inclination on the Hydrodynamics of Slug Flow
Authors: Dafyak Longtong , Appah Dulu , Onuoha Sean , Mukhtar Abdulkadir 
Published: October 2018

Abstract
There is a general lack of studies addressing the optimization of hydrocarbon flow conditions in pipes passing through hilly terrains. Most of the studies carried out on two-phase flow are for fluids flowing through vertical and horizontal pipes. For studies carried out on inclined pipes, a large proportion are on air-water mixtures. To address the aforementioned challenge, there is a need to study the hydrodynamics of slug flow in various pipe inclinations with a focus on fluids with properties that replicate the behavior of effluents seen during crude oil production.
This study provides a foundational perspective into the physical phenomenon that governs the behaviour of slug flow and the variation of slug flow parameters as the pipe deviated from horizontal to vertical. To clarify the effect of pipe inclination on the hydrodynamics of slug flow, the characteristics of fully developed multiphase air-silicone oil mixture flowing in a 67 mm diameter pipe and inclined at 0, 30, 45 and 90 to the horizontal was investigated. Fluid flow properties over the range of superficial gas and liquid velocity were measured using Electrical Capacitance Tomography (ECT) and analyzed using Probability Density Function (PDF) and Power Spectral Density (PSD) plots to determine; mean void fraction, void fraction in the liquid slug and Taylor bubble, structure velocity, slug frequency and slug unit.
The mean void fraction decreased as the pipe inclination advanced from 0° to ~45°, it then increased between ~45° and 90° to the horizontal; the angle at which it begins to increase seems to be around 45°. The void fraction in the liquid slug increases as pipe inclination tends towards the vertical from the horizontal axis. In the case of the void fraction of the Taylor bubble, no unique trend was observed as the pipe inclination changed. The slug frequency increased with pipe inclination and liquid superficial velocity at a constant gas superficial velocity. In addition, the structure velocity increased as the pipe inclination advanced from 0° to 45°, it slightly decreased again between 45 and 90 to the horizontal. The slug unit in horizontal pipes is far greater than that obtainable in pipes inclined between 30° and 90°, at superficial velocities of 0.05 m/s and 0.157 m/s. However, at higher superficial velocities between 0.262 m/s and 0.514 m/s, the slug unit ranges from 0.6 to 1.8 m for all pipe inclinations. It was also confirmed that for upward inclined flow, the dominant flow pattern is intermittent flow.
Type-Curve Analysis Using Homotopy Analytical Technique for Evaluation of Reservoir Rock Properties
Authors: Ayuba Ibrahim , Adamu M. B. , Salahudeen Ibrahim , Faruk A. U. , Ismail H. 
Published: October 2018

Abstract
Homotopy analytical method (HAM) is a computational method that provides solution to highly non-linear partial differential equations (PDE's) in much similar way as other perturbation and asymptotic techniques. This research work illustrates the benefit of using (HAM) to obtain a type curve over conventional log approximation of dimensionless variables. From such type curves, average reservoir properties, porosity and permeability were obtained from dimensionless equations. This type curve was obtained by matching plots from HAM solution and well test data. The HAM is independent of small/large parameter and can be used to obtain analytical solutions to highly nonlinear partial differential equations unlike other analytical and asymptotic techniques applies to weakly nonlinear problems. The HAM solution gives values of reservoir pressure distribution as a continuous function of time and converges easily for large reservoirs (rD =380) typically. One advantage of HAM is that it provides a means to ensure convergence of series solution by introduction of convergent control parameter. Plots of reservoir pressure distribution as a function of time curves were also obtained and extrapolated for easy matching and were matched with the type curve. Dimensionless pressure and time were used to compute average porosity and permeability which were found to be 1.51md permeability and 1.81% porosity. Computer program was developed for computations using MATLAB and further analysis of data using EXCEL. From the match points obtained, reservoir properties were estimated.
Completing the Value Chain for Plastic Recyclers in Nigeria: An Integration of Renewable Solar and Conventional Gas Energy Sources for Fuel Production
Authors: Stephen Okocha , Okonkwo Ebenezer , Ogbonna Joel 
Published: October 2018

Abstract
It is of no new update that plastic recycling has taken another dimension in advanced countries all around the world. This is owing to the enormous plastic wastes being produced amounting to about 9 billion tonnes since the first production and the immerse technological advancements which can be seen in pelletizing plants, pyrolysis plants and 3D printers of today. However, here in Nigeria, the case of large plastic waste generation cannot be over emphasized, as efforts in recycling has being hampered consequently from low power generation of the National grid, high energy cost (fuel and electricity), polymer waste selectivity and even low capital resource from most parts of the country. Hence, this paper looks at the development of a solar-vacuumed actuated pyrolysis plant integrated with gas combustion energy supply which will employ the use of concentrated solar energy as the primary energy source for pyrolysis reaction for fuel production and use the flee gas from the reaction as an alternative energy source. A process flow configuration (PFD) involving the reactor, solar lenses, vacuum pump, solar panel, inline components and the condenser is set up to perform the thermal gasification and condensation of waste plastics in the reactor. Computationally, the finite element analysis (FEA) was done to see the thermodynamic effects inside and outside the reactor for effective fuel production. The idea is to ascertain that the inside temperature of the reactor which was initiated by solar thermal energy is enough to attain the boiling point of about 400°C of most plastic polymers but in vaccum conditions. When accomplished, this will complete the value chain of plastic recycling, eliminate plastic waste selectivity in terms of colour and type, sanitize the environment and create jobs for future entrepreneurs in Nigeria.
Alerting Excessive Choke Increase Impact on Water and or Gas Production Responses Vs. Oil Cumulative- PredOPT
Authors: Morais E. I. , Fernandes G. C. , Chitangueleca B. , Ibelegbu C. C. 
Published: October 2018

Abstract
Angola's O&G business environment has shifted from Exploration to Production, and from Drilling to Well Intervention for obvious reasons of current and projected state of the E&P industry where operations are squeezed by volatile oil prices and higher operating costs. Operators in quest to maintain production plateau resolve in excessive choke increase. Therefore, a focus on predicting resulting HWcut and or HGor over time becomes significant as 75% of fields are under fluid injection for a balance voidage replacement.
This study uses fields in Angola for conventional diagnostics decline curve analysis. Using plots of cumulative oil vs GOR, Pressure, Water cut and choke, to analyses the water and or gas production responses vs. oil cumulative to the excessive choke change. To have a complete sense of the impact, PI is included to consider oil production with respect to pressure drawdown. This study where mainly focused in clastic deposits.
This approach may help anticipate the production of water due to excessive increase in choke sizes. It is expected that depending on the provenance of the water, it is concluded that excessive choke variation can be problematic in the future. A possible warning or alert is generated for any future choke change and hence oil production is optimized. An excel macro coding- PredOPT (Prediction and Optimization) is developed for the analysis and plugged-in to commercial software for the ease of applicability.
A Look at History-Match Non-Uniqueness Through the Lens of Model Simplifications - Delta Reservoir Case Study
Authors: Jaja Adagogo J. , Ambastha Anil , Aina Soji , Eme Vincent , Bere Barienea 
Published: October 2018

Abstract
Reservoir simulation is one subject with different "schools of thought" for its ability to predict the future performance of a reservoir. An important topic in reservoir simulation workflow is the parameters used to achieve history-match. The non-uniqueness of history-match parameters creates an opportunity for reservoir simulation engineers and geologists to engage in collaborations that ensure geological and engineering interpretations are incorporated in history-match parameters.
Simple history-match parameters are often times preferred by practitioners to complex history-match parameters. This paper will discuss Delta reservoir history-match parameters used in a 2014 reservoir simulation study which was later updated in 2016 with simplified history-match parameters. The parameters that were simplified are permeability multipliers, oil/water relative permeability and the use of Land's constant. Also, vertical grid refinement was implemented to reduce it from 8ft to 2ft to enable the simulation model reproduce the reservoir fluid distributions in the two lobes of the reservoir. With all these modifications, there were no significant differences with the wells’ static reservoir pressure and fluid saturation matches between the 2014 simulation study and the 2016 simulation update. This paper demonstrates the non-uniqueness of reservoir simulation history match parameters and the value to consider simple grid and fluid parameters’ modification before considering complex approach.
With the simplified history-match parameters, the Asset Team had more confidence in the simulation result. The updated Delta reservoir simulation model was used to assess future development opportunities and identified two oil-well producers and one water injector well with EUR of 13.3 MMSTBO.
Development Strategies for Oil Reservoirs with Coning Problems: A Simulation Case Study
Authors: Stanley Okafor Ikechukwu , Ebenezer Ubani Chikwendu , Anyanwu Nnaemeka 
Published: October 2018

Abstract
Water coning in oil reservoirs is a complex phenomenon which poses a problem in the petroleum industry today. The upward movement of water into the production interval has an adverse effect on the production facilities and the total oil recovery of a particular field. In this paper, different strategies for analyzing and developing reservoirs with coning problems were developed and different implementation steps were suggested to properly optimize the recovery of these reservoirs. Our case study is an oil reservoir in the Niger delta region with strong aquifer drive. A numerical reservoir simulation study was carried out based on the structural top and base maps generated using 3-D seismic estimated reservoir rock and fluid properties, using actual reservoir/well data. Also, production performance analysis were carried out to ascertain the causes of non-conformance issues like high BSW, decline in production and reservoir pressure. Perforation panel plots were constructed for the Levels with respect to the initial fluid contacts to diagnose for high water cut, to investigate their impact on future performance scenarios and productivity of the currently producing wells. The recommended development scenarios were also compared with the nature and structure of the reservoirs (high dip and low dip) to show the best well patterns/placements that will improve recovery.
Profitability of Marginal Oilfields in a Low Oil Price Regime: A Stochastic Modelling Analysis
Authors: Adeogun Oyebimpe , Iledare Omowumi , Idowu Adekunle J. 
Published: October 2018

Abstract
Marginal fields are typically characterized by low reserves, high sensitivity to oil price, high subsurface uncertainties, and significant economic and technological constraints. Despite these challenges, they remain a viable tool for local content and sustainable economic growth. Recent reports showed that they accounted for about 10% of total crude oil production in Nigeria. This contribution is quite low but more might be expected in the coming years. The interplay of cost, oil price and fiscal regime has significant impact on the profitability of marginal field assets because of the small reserves size. With persistence low global oil price regime, it has become imperative to critically analyze the economics of marginal oil fields in Nigeria. It is usual for government to design stable and flexible fiscal regimes for marginal field operators in order to capture unforeseen uncertainties peculiar to the oil and gas industry. This paper seeks to examine the profitability of marginal field operators under the prevailing fiscal regime. In addition the paper intends to recommend measures that can be taken to ensure profitability of marginal field despite declining oil prices. An economic model and stochastic simulation using prevailing fiscal regime showed that marginal field operations will be profitable if and only if reserves were at least 10 MM bbl. However, for smaller field size than 10 MMbbl, marginal field development may only add value with economic and policy incentives and cost minimization strategies. Thus, it is recommended that tax holiday should be given when oil price drops below $35/bbl. in order for marginal field development to add value.
Analysis of Government and Contractor Take Statistics in the Proposed Petroleum Industry Fiscal Bill
Authors: Nwosi-Anele Adaobi Stephenie , Adeogun Oyebimpe , Iledare Omowunmi 
Published: October 2018

Abstract
Fiscal system is the basis for the estimation of take statistics ratio between Government and Contractor. This has been the case for the different versions of Nigeria's Royalty and Tax system and Production Sharing Contracts. Modifications in the currently proposed petroleum industry fiscal bill promise to ensure oil and gas availability, accessibility and affordability. Favorable upstream petroleum operations underlie the development and expansion of the midstream and downstream sectors. Fiscal incentives available to contractors make investment a worthwhile venture for both the government and contractor. The recently proposed petroleum industry fiscal bill (PIFB) 2017 is a favorable development because it is anticipated to reduce tax burden on investors, increase government take from royalty schemes and a dual tax system imposed on oil and gas projects. This paper applies a deterministic and stochastic cash flow model, analyzes the fiscal provisions of the existing royalty and tax system, production sharing contract and the proposed petroleum industry fiscal bill, 2017. Results from the model present a friendly royalty and tax deduction strategy in the proposed bill, which provides an incentive for investors to re-invest in the midstream and downstream sectors. However, the provision in the petroleum industry fiscal bill (PIFB) 2017 for royalty deduction during windfall is rather too fair at $50/bbl, considering a benchmark profitable oil price of $35/bbl during windfall. This paper suggests $35/bbl price for windfall threshold price for the additional $0.2 per dollar increase in oil price for royalty by value determination.