bluuebunny/crossref_metadata_2025 huggingface dataset:
Dampak Krisis Finansial Global dan Kebijakan Antisipatif Pengembangan Industri Kelapa Sawit
Authors: Dradjat Bambang
Published: July 2017

Krisis finansial global (KFG) yang terjadi pada tahun 2008 ternyata menimbulkan resiko dan ketidakpastian bagi pengembangan industri kelapa sawit. Dalam jangka yang sangat pendek, harga minyak sawit terpukul. Importir dari AS, negara-negara Eropa Barat, Cina, India dan Pakistan - yang mengalami dan terkena dampak KFG – menunda bahkan membatalkan kontrak sehingga ekspor minyak sawit Indonesia terganggu. Pengkajian kebijakan ini bertujuan untuk : (i) mengidentifikasi dampak KFG terhadap industri kelapa sawit, dan (ii) mengevaluasi pengaruh berbagai kebijakan antisipatif pemerintah dan faktor eksternal pada industri kelapa sawit. Dampak yang ditimbulkan dari KFG pada industri kelapa sawit Indonesia berupa tekanan harga, ekspor dan produksi. Antara bulan Oktober 2008 hingga Maret 2009, harga CPO dan TBS terendah dan sempat menyentuh US$ 483 per ton dan Rp. 584 per kg. Tekanan harga selama KFG membawa dampak pada penurunan volume ekspor bulanan minyak sawit jatuh hingga hanya 937.000 ton. Sedangkan produksi bulanan minyak sawit sempat hanya mencapai 815.000 ton. Kebijakan lobi internasional kombinasi Government (G) dan Business (B), penyesuaian kebijakan BK, kebijakan perluasan formula harga TBS, peningkatan akses informasi harga, dan peremajaan merupakan kebijakan antisipatif utama yang direkomendasikan dari kajian ini. Kebijakan ini diperlukan supaya jika krisis berulang atau terjadi lagi, industri kelapa sawit mampu bertahan dari tempaan krisis. Jika pemerintah tidak menerapkan kebijakan ini, resiko yang ditanggung akan lebih parah sehubungan dengan makin berkembangnya perkebunan kelapa sawit rakyat swadaya/mandiri. Dampak negatifnya adalah kontribusi industri kelapa sawit dalam perekonomian nasional dapat terganggu.
Dampak Kebijakan Fiskal dalam Upaya Stabilisasi Harga Komoditas Pertanian
Authors: Sujai Mahpud
Published: July 2017

Fluktuasi harga komoditas pertanian saat ini sudah mencapai kondisi serius sebagai akibat peningkatan permintaan tidak diimbangi dengan penawaran yang cukup. Selain itu kondisi iklim yang tidak menentu dan instabilitas politik global mengakibatkan pula peningkatan harga komoditas pangan internasional. Salah satu cara Pemerintah guna meredam fluktuasi harga komoditas pertanian adalah dengan implementasi kebijakan fiskal yang tepat berupa pemberian subsidi, insentif fiskal termasuk keringanan perpajakan dan bea serta optimalisasi anggaran. Temuan pokok kajian ini adalah (a) fluktuasi harga komoditas pertanian berdampak signifikan terhadap inflasi dan menciptakan instabilitas harga dan pasokan pangan; (b) pemerintah telah menggunakan berbagai instrument kebijakan fiskal dalam upaya stabilisasi harga dan ketersediaan pasokan pangan; (c) kebijakan fiskal Pemerintah telah membuahkan hasil terbukti dengan terus turunnya inflasi di triwulan I tahun 2011 hingga mencapai 6,16 persen year on year pada bulan April 2011; (d) kebijakan fiskal berupa insentif perpajakan dan bea hanya berlaku sementara dibarengi dengan upaya peningkatan produktifitas produksi pertanian. Antisipasi kebijakan fiskal ke depan akan penuh tantangan seiring dengan semakin meningkatnya tekanan perubahan iklim dan kondisi geopolitik internasional. Karena itu kedepan rekomendasi kebijakan yang bisa diimplementasikan antara lain (a) kebijakan fiskal yang diambil jangan sampai merugikan petani dan menjadi disinsentif terhadap pengembangan sektor pertanian dalam negeri (b) penurunan tarif bea masuk terhadap komoditas pertanian harus bersifat temporer karena akan merugikan petani dalam negeri jika diberlakukan dalam waktu yang lama (c) pemerintah harus tetap memproteksi sektor pertanian dalam negeri untuk menciptakan ketahanan pangan dan kesejahteraan masyarakat.
Keragaman dan Kekerabatan Genetik Koleksi Plasma Nutfah Teh Berdasarkan Karakter Morfologi Daun dan Komponen Hasil
Authors: Rahadi Vitria Puspitasari , Khomaeni Heri Syahrian , Chaidir Liberty , Martono Budi
Published: July 2017

Tea (Camellia sinensis (L.) O. Kuntze) is a cross-pollinated plant that has self-incompatible character. Assembly of superior clones through artificial pollination requires information of genetic relationships between accessions as a reference for parental lines selection. The study was aimed to determine the genetic diversity and relationships of 49 tea clones based on leaf morphology and yield components. The research was conducted at Pasir Sarongge experimental garden, Cianjur, West Java, from April to November 2015. The observed morphological characters were leaf length and width, leaf area, leaf angle, number of vein leaf, and internode between first and second leaves. Meanwhile, yield components were pecco number, pecco weight (p+3), banji bud number, banji bud weigth (b+1), and yield. The data were then used for descriptive analysis and grouping using UPGMA method based on dissimilarity matrix by XL-STAT software version 2009. The research showed that 49 clones observed here have variability on yield, leaf area, number of banji bud, and pecco number with coefficient of diversity 27.77%–51.83%. On the other hand, result of cluster analysis divided tea clones into four groups. The first group consisted of 34 clones with morphological characteristics similar to sinensis type (narrow leaves and low productivity). Group II comprised 12 clones with morphological characteristics (wide leaf) and productivity (high) similar to assamica type. Group III and IV, each contained one clone, and have similarity to assamica. The most far genetic relationships was found between group I and II (55.59%), while the closest one observed between group III and IV (5.76%).
Mutu Fisik Biji dan Citarasa Kopi Arabika Hasil Fermentasi Mikrob Probiotik Asal Pencernaan Luwak
Authors: Towaha Juniaty , Rubiyo Rubiyo
Published: July 2017

Civet coffee is produced through microbial digestion inside the civet’s tenue intestinal and caecum. Therefore, fermented coffee using probiotic microbes isolated from the civet digestive organs presumably will produce coffee with a distinctive flavor and aroma, which is similar to civet coffee. The research aimed to determine the effect of the fermentation period on physical quality of beans and flavor profile of probiotics Arabica coffee. The research was conducted at Belanga and Belantih Village, Kintamani District, Bangli Regency, laboratory of Assessment Institute for Agricultural Technology (AIAT) Bali, laboratory of Indonesian Coffee and Cocoa Research Institute Jember, and laboratory of Indonesian Center for Agricultural Postharvest Research and Development Bogor, from June to December 2013. Fermentation was carried out in 2 phases: (1) fermentation using probiotic microbes isolated from civet’s intestum tenue, (II) fermentation using probiotic microbes isolated from civet’s caecum. The treatments were arranged as follows: P1 = fermentation at phases I and II, each for 4 days, P2 = fermentation at phases I and II, each for 5 days, P3 = fermentation at phases I and II, each for 6 days, P4 = fermentation at phases I and II, each for 7 days. The result showed that probiotics Arabica coffee has a reasonably good physical quality and met the requirements of SNI 01-2907-2008. The best flavor was obtained in 2 fermentation phases, each for 6 and 7 days with a total score of 81.44 and 80.91, respectively, which then classified as specialty coffee. The qualities shown are better compared to original Arabica civet coffee.
La fragilidad no se asocia con una baja frecuencia de vacunación en adultos mayores
Authors: Delgado-Arce Julio César , García-Lara Juan Miguel Antonio , Pérez-Zepeda Mario Ulises , Avila-Funes José Alberto
Published: July 2017

Señor editor: Los adultos mayores son particularmente susceptibles a infecciones respiratorias, por lo que la prevención de éstas es fundamental para disminuir complicaciones. Por otra parte, en geriatría, “fragilidad”describe un estado de gran vulnerabilidad y pobre resiliencia, el cual no debería excluir a las personas frágiles del beneficio de intervenciones tales como la vacunación, bajo el argumento infundado de que ésta es inútil.
Sordedad, una nueva forma de pensar y vivir la sordera
Authors: Muñoz-Vilugrón Karina , Osses-Bustingory Sonia
Published: July 2017

Señor editor: Tradicionalmente, en la construcción social en torno a la sordera, prevalece la concepción médica, vinculada con la idea de normalidad, basada en un diagnóstico médico, legitimada por un discurso que promueve un saber y en la cual la sordera requiere una rehabilitación...
Niños en cuerpos de adultos
Authors: Ramírez-Bermúdez Jesús , Corona Teresa
Published: July 2017

Niños en cuerpos de adultos es un libro breve que puede leerse en una sesión de lectura, pero cuyo contenido es lo suficientemente extenso como para explorar los puntos críticos más relevantes para el entendimiento de la discapacidad intelectual. Los autores, Eduardo Lazcano y Gregorio Katz, tienen una amplia trayectoria en este campo del conocimiento: han realizado una gran labor científica, epidemiológica y de difusión al respecto. La edición a cargo de Carlos Oropeza, el Instituto Nacional de Salud Pública y SPM Ediciones ha sido cuidadosa en aspectos de diseño y formato.
Leaving no child with disability behind
Authors: Skoog Christian
Published: July 2017

In Latin America and the Caribbean there are over eight million children with disabilities under the age of 14, representing one of the most excluded, discriminated and vulnerable population groups in the region. Among them, girls with disabilities and indigenous children with disabilities are subject to multiple forms of discrimination. It is estimated that seven out of ten children with disabilities do not attend school, and that at least 50 000 children and adolescents with disabilities are deprived of their family environment and live in residential institutions, representing 20% of all children living in residential care in our region.
Gas Identification in Thin Beds using LWD Measurements-West Africa Offshore Example
Authors: Oifoghe Stanley , Daniel Ono , Okowi Victor , Thompson Charlie
Published: July 2017

Gas identification and determination of Gas-Oil Contact (GOC) in reservoirs containing gas and oil can be a major challenge in laminated sand-shale sequences, where the presence of shales drastically affects the response of gamma ray, resistivity, density and neutron logs. Due to the resolution of these measurements, it becomes increasingly difficult to identify and quantify the gas reservoirs.

In a West Africa offshore well in a Cretaceous formation, using a Penta-Combo Bore Hole Assembly (BHA) with basic Formation Evaluation (FE) measurements, the use of additional services such as Nuclear Magnetic Resonance (NMR) and Formation Pressure Tester Logging While Drilling (LWD) services, significantly improved the confidence in interpretation of the reservoir fluids.

In the example well, though the size of the density-neutron crossover showed a reduction in the oil zone as compared to the gas zone to a certain degree, the actual position of the Gas/Oil contact and the reservoir fluid saturation were not certain. Using the traditional NMR porosity undercall in gas zones as well as the dual wait time (DTW) tranverse relaxation time (T2) distribution analysis, the gas zone was confirmed and the saturation of each of the fluids in the reservoir was accurately determined.

The NMR tool was programmed to acquire data in dual wait time (DTW) mode to calculate hydrocarbon saturation. The Magnetic Resonance Dual Wait Time (DTW) approach takes advantage of Longitudinal Relaxation Time (T1) contrast to solve for hydrocarbon saturation. "In light hydrocarbons, in a water-wetting reservoir, the hydrogen atoms in the hydrocarbon fluid relax slower than the nonmovable and movable water. By using two polarization or wait times (Tw), it is possible to calculate hydrocarbon saturation using magnetic resonance tools" (Thorsen et al., 2008,). Due to the long T1 of gas, the short wait time will only polarize a fraction of the porosity in the gas zone while achieving a near full polarization in the liquid (oil or water) zone.

Also, the gas hydrogen index effect was evident in the total porosity computation from NMR measurement. Significantly lower porosity was observed in the gas zone as compared to the oil zone. This was the first indication of Gas-Oil contact (GOC). Further analysis of the dual wait time T2 distribution gave a proper estimate of the saturation of the fluids in the reservoir.
Constraints in Sustainable Development of Marginal Oil Field in Niger Delta Region
Authors: Otombosoba Oruwari Humphrey , Dosunmu Adewale
Published: July 2017

Economic, environmental, natural, socio political, technological and other man made circumstances aggregate into sources of risk which result in the main constraints to sustainable development of marginal oil fields in Niger Delta region. For marginal oil fields, the constraints may further reduce the economic viability as well as result in devastating consequences to the environment. The paper examines the causes of the main constraints to marginal oil field development and the associated consequences in Niger Delta region. The identification of the main constraints to marginal oil field development presents opportunities for continuous improvement and possible reduction in the cost of operations of the marginal fields in Niger Delta region. The study provides new information that is not publicly available for Niger Delta region and serves as a useful guide for investors wishing to participate in the sustainable development of marginal oil fields in Niger Delta region. Adopting an innovative methodology, involving literature and document analysis the study identifies economic condition, know-how and institutional capacity as the key constraints in sustainable development of marginal oil fields in Niger Delta region. Although security concerns are significant with outlying step influences, however, we also established that other non-technical factors result in the main constraints to marginal field development among which are funding, technical expertise, government policy and marginality of the field. The solution lies in addressing these burning issues. The paper provides a strategic management model for sustainable development of marginal oil fields in Niger Delta. The proposed model can be applied as input into a wider risk assessment framework for investment decision.
Nigerian Content Development in the Oil and Gas Sector: The Role of the Nigerian Academia
Authors: Idachaba Francis Enejo
Published: July 2017

The oil and gas production process is driven by technology. The impact technology plays in the process is such that the oil and gas industry ranks as one of the largest employers of PhDs and also one of the largest investors in Research and Development activities. These have resulted in the industry being also one of the industries with the largest number of expatriates. Countries with large oil and gas deposits have oftentimes relied on International Oil and Gas companies for the exploration of their deposits with the hope that the knowledge and technology will be transferred over time. This has not been the experience in a number of these countries and has caused them to develop deliberate programs and local content development policies to encourage and engage the local populace in the oil and gas production process. For the local content policies to be maximized, local companies must invest in research and development efforts to create value and develop relevant technology as this is the only way they can maximize the oil and gas related contracts. Investment in Research and development is a highly capital intensive and time consuming process and as such it is out of the reach of the local companies. This paper discusses the role of the academia in the development of technology and the local content. It also presents some strategies that can be deployed to engage the Nigerian Academia in the development of the local content in the oil and gas sector in Nigeria.
Use of Standard PVT Measurements to Enhance the Understanding of Reservoir Behavior
Authors: Fabbri C. , Poirier Y. , Odeniyi Odeniyi , Mayembo-Kehoua D. , Imeokparia D. , O. Udoh D. , Umoh E. , Lanisa A. , Fashanu M. , Tremaudant C.
Published: July 2017

In the Amenam-Kpono field, three main reservoirs are currently being produced: R11, R10 and R4. During the first phase of its development, the production strategy was to re-inject the associated gas from all reservoirs into the R4 reservoir in order to maintain the initial reservoir pressure above the saturation pressure, close to initial pressure. The deeper reservoirs R10 and R11 were first produced under natural depletion as their initial pressures were far from saturation pressure. Water injection was progressively deployed on R4, R10 and R11 in order to ensure voidage replacement.

In order to monitor the efficiency of gas injection, a gas tracing campaign has been carried out in 2005, improving the understanding of R4 flow barriers and showing that some of the gas injected had broken-through. However, ideally, such a campaign should be repeated regularly so as to take into account the change in pressure regimes that will affect the dynamics of the field. In practice, implementing it regularly is challenging, due to the cost associated to the chemicals and logistics. This paper aims to describe a "low cost" monitoring method based on produced gas composition follow-up and its evolution through the life of the field. It shows how the composition of the gas produced has been recently used as a natural tracer. This approach has improved the understanding of the reservoir dynamics, in terms of compartmentalization and flow distribution across different perforations.
Overpressure Analysis in HPHT Environments: Lessons Learned from the Central North Sea
Authors: Nwozor Kingsley
Published: July 2017

The uncertainties of overpressure estimation are among the major challenges to the development of deep and hot reservoirs in many sedimentary basins especially with regards to drilling safety and well economics. However, because of the anticipated huge economic benefits of HPHT geological environments, stakeholders in the oil and gas industry consistently seek to have a good understanding of subsurface pressure systems in order to promote safe and sustainable investments therein. Accordingly, information is required to improve the regional knowledge of geopressures and for the calibration of functions aimed at optimising pre-drill pore pressure estimates for future wells. The Central North Sea, with its vast number of HPHT wells, pressure data, drilling information and documented operational experiences in exploration, drilling, development and production activities stands in a good stead as a "geopressure laboratory" for the fine-tuning of pore pressure prediction concepts, improvement of current geopressure practices and ultimately guide investment and operational decisions in the unexplored areas of the basin itself and elsewhere as geological realities could permit. For this reason, this study utilised downhole pressure-related data and wireline logs to evaluate the pressure regimes in the Central North Sea. The approach involved the quantification of overpressures using standard pore pressure prediction methods that make use of the density and velocity logs of mudstones. The results show that the estimated pore pressure profiles are consistent with measured pressure data in the Cenozoic formations, which makes it reasonable to assume that disequilibrium compaction is the cause of overpressure in this shallow section of the wells. Going deeper into the wells, within the sub-Chalk section, typical calibration parameters from log data could not be used to achieve reliable estimates of overpressures as was the case in the Cenozoic section. Remarkably, while it is possible to adjust the Eaton exponents in order to match estimates with measured data, a wide range of exponent values of between 4.0 and 7.0 is however required. The implication is that there is no systematic variation of the Eaton exponents with the amount of overpressure or depth of burial of the sub-Chalk strata.
Experimental Study of the Possible use of Locally Derived Plantain Peelings and Rice Husk as Additives for Oil Based Mud at High Temperature - High Pressure Conditions
Authors: Seteyeobot Ifeanyi , Uma Joshua A. , Enaworu Efeoghene
Published: July 2017

Drilling in HT/HP wells has adverse effects on drilling fluids. At high temperatures and pressures, the chemical additives used in drilling fluid formulations experience thermal degradation above 107°C (225°F) leading to strong variations (reduction) in rheological and filtration characteristics. Locally derived Rice-Husk and grounded Plantain peels were used to improve the rheology and filtration properties of back-loaded oil based mud at HT/HP behavior, and the results were compared to industrial additives like Sodium Carbooxymethylcellulosics (CMC), Polyanionic Cellulosics (PAC), and Sodium Polyacrylates (SPA). This research was centered on the use of three oil-based mud samples from a particular field in the Niger Delta basin. The samples included; a reconditioned mud, a freshly prepared mud (both with standard industry additives), and a back-loaded mud respectively. Seven [7] different mud property tests were carried out on the samples to determine their current state. After that, the back-loaded mud was upgraded with the locally derived additives and it's rheological and filtration properties were observed and compared to the results of the first two samples. The effects of high temperature and high pressure on the stability of the locally-derived additives were also observed. This was paramount because the chemical additives underwent thermal degradation at these conditions. The most significant finding is that the locally derived additives worked at the same level or probably better than the industrial additives.

The novelty of this research was to evaluate the potential of locally derived additives for improvement of mud rheology and filtration in comparison with industrial additives. Also, a reduction in the cost of purchasing foreign viscosifiers and filtration control additives by patronizing locally derived additives hence reducing the overall cost of a mud program. Lastly to make sure that wastes like rice husks and plantain peelings are recycled by usage in drilling mud formulations so as to prevent environmental problems such as heaping of refuse on the streets.
A Fit for Purpose Probabilistic Forecasting Tool PFT for Business Planning
Authors: Olayomi A. J. , Jaja A. J. , Adegboye P. S
Published: July 2017

The need for reliable and efficient production forecasts for business planning cannot be overemphasized. Production Forecasts are the underlining basis on which many business decisions are made. They also serve as main input into economics and decision analysis and are used for project selection. Until recently many organizations tend to rely on deterministic forecasting methods with inherent pitfalls since they don't include uncertainties in the estimates. While there are existing methods such as reservoir simulation for generating probabilistic forecasts for oil and gas, those methods are either expensive or take too long to deliver or a combination of both. The substantial investment in time and capital make these tools less available for making day to day decisions and preparing annual business plans to identify targets for the upcoming year.

The Probabilistic Forecasting Tool (PFT) was developed as a cost effective and user-friendly tool for generating reliable probabilistic production forecasts for oil, gas and water. It enables oil and gas companies to estimate a range of production forecasts using several input parameters and to evaluate the impact of each of the input parameters on the forecasted production. This tool has also found wide application in preparing monthly production outlook which might be too granular and resource-inefficient for full-blown simulation modelling.

The PFT was developed in Microsoft Excel with a built-in decline engine and incorporates a wide variety of inputs such as peak production rate, decline rate, workovers, planned/unplanned downtime, new drills, rig schedule etc. on which sensitivity analysis could be conducted. Probabilistically combining the low, middle, and high estimates of the input parameters, the PFT uses monte-Carlo simulations and Excel macro automations to generate uncertainty ranges around the input parameters. The tool then generates a cumulative probability density function of the profiles from which the forecasts at different percentiles could be evaluated

This paper will describe the probabilistic Production Forecasting Tool (PFT), its application for short term oil, gas and water forecast using decline curve analysis engine (DCA) as its foundation. It will describe the workflow for the integration of different assumptions on projects, planned downtime and unplanned downtime and show a few case histories. The application of this tool has helped in reducing man-hours required to use complex reservoir engineering forecasting tool for the same purpose. This tool has shown reliability in the production forecast numbers compared to actual production data in over eight years of its application.
Estimation of Oil-Rim Thickness with Analogue Data in the Absence of Definite Fluid Contacts: A Case study from Onshore Niger Delta
Authors: Fouzdar Amit , Kilic Cem , Das Anindya
Published: July 2017

One of the major challenges in field development is to estimate the possible oil-rim thickness, when only known contact is Gas-Down-To (GDT) or Oil-Down-To (ODT), and where seismic analysis cannot resolve the uncertainty. A reliable, repeatable, and practical technique to estimate the ranges of possible oil-rim thickness with the regional analogue would allow for making development decisions, as well as meeting the local regulatory requirements. An analog database with numerous proven hydrocarbon (gas and oil) column heights provides a trend for "gas-to-oil column ratio" by depth, which can be used for predicting possible oil-rim thickness at specific reservoirs with the contact uncertainty. For all the analog reservoirs, fluid thicknesses have been tabulated and a "gas-to-oil column ratio" has been calculated. A simple plot between the "gas- to-oil column ratio" and reservoir depth reveals a certain trend of increasing "gas- to-oil column ratio" by depth. In addition, database also provides a cumulative distribution of regional column heights, which could be used to constrain the maximum estimated hydrocarbon column thicknesses. The trend of increasing "gas-to-oil column ratio" by depth indicates that gas-columns gets much bigger compare to oil-columns as the reservoir depth increasing. With given depth information and estimated "gas-to-oil column ratio" from the database, it is possible to estimate possible range of oil-rim thickness. By investigating the scatter in the trend, it is also possible to estimate a range of "gas- to-oil column ratios". With the help of this methodology, in absence of any definite fluid contact, it is possible to estimate a range of oil-rim thicknesses, which has an impact on field development scenarios; i.e. "gas-only", "oil-then-gas", or "concurrent oil-and-gas" development options. In addition, it could also help field development plan to meet the regulatory requirements; i.e. providing a strong case not to develop or appraise the oil rim.
Localized Pitting Corrosion of Super Duplex Stainless Steel in a Sea Water Application: Practical Case of When Chlorination was Not to Blame
Authors: Alum Moses A.
Published: July 2017

The Fire Water Pump (FWP) Columns were being dismantled and removed on August 3rd 2015 for the installation of anodes originally not installed barely one year after plant start-up in December 2014, in a re-developed Brown Field offshore Nigeria.

Given that the material used in the manufacture of the columns were made of A890 Grade 6A (Super Duplex Stainless steel) materials, the unexpected was observed, "Severe localized pitting corrosion" from the internal on one of the seawater submerged section of the columns (column 9), and on further examination of the pitting, two (2) pin holes were found. This discovery led to stoppage of the activity, and to dismantle and remove already coupled columns 11 and 10 (which had the anode already clamped on it) for additional inspection.

Visual Inspection and thickness measurements were carried out on all the eleven (11) columns of the FWP on the 4th August, 2015, and similar observations were made. It is well known and demonstrated that the performance of Super Duplex stainless Steel in Seawater conditions has generally been excellent with few problems, so why did we have these pitting corrosions less than one year after the Pumps were put in service? The usual culprit, Chlorine, known to initiate Chromium-oxide breaks at the passive film of stainless steel material thereby increasing their susceptibility to localized pitting and crevice attack was initially suspected. However, practical examples and applications show that Super Duplex Stainless steel can still be resistant to both pitting and crevice corrosion even in extreme corrosive conditions of excess chlorine dosing. So what went wrong? Further investigations were carried out to answer the posers.

This paper will tell us what went wrong and why. It is a practical case study of where even though sea water chlorination was present, yet it wasn't the dominant factor that led to severe localized pitting corrosion and holes in Super Duplex stainless steel materials.
Multi-Tank Material Balance Analysis in Heterogeneous Oil Reservoirs
Authors: Molokwu V. C. , Onyekonwu M. O.
Published: July 2017

This paper presents detailed theories and method of determining fault transmissibility and production history matching using the multi-tank material balance. This approach uses a two-step optimization process whose algorithm can be written as macros in spreadsheets. The upper-level (outer) stage optimizes the transmissibility and hydrocarbon initially-in-place while the lower-level (inner stage) optimizes the pressure of the support tank at each time step. This approach is validated using numerical simulation. This approach will be highly beneficial in effective reservoir management where little or no 3D seismic exists and for cases of sparse production data.
Optimizing Reservoir Ultimate Recovery and Reserves Replacement via Efficient Opportunity Generation
Authors: Dennar Linda , Emelle Chima , Essien Uwem , Suleiman Ahmed
Published: July 2017

Having a long-term plan to maximize economic recovery of hydrocarbons whilst delivering reserves today is at the core of sustainable development in EP Business Plan Priorities (especially reserves replacement ratio and growing the resource base).A typical hydrocarbon maturation funnel, which is a graphical representation of existing projects underpinning the maturation of volumes gives insight into the maturity of the projects, sustainability of production, reserves replacement over time and availability of maturation options. At reservoir or field level they provide information on the ultimate recovery that is currently expected and highlight which recoverable volumes are not yet underpinned by projects.

Continuous refreshing of the maturation funnel can never be overemphasized and the success of this refresh is determined by the quality and number of opportunities generated over time that gives an accurate perspective of the full life cycle recovery expected from the reservoir, rolled up to the field level. The objective of an effective opportunity generation process is to clearly identify new projects and provide answers to certain pertinent questions like; a) are all the volumes in this funnel supported by projects? b) what reserves replacement does the funnel yield in the next 5 years? c) what ultimate recovery does the funnel yield? d) What type of recovery processes will be employed now and in the future?

Field A was used as a case study to test the efficiency and impact of this process with special reference to production sustenance and life cycle recovery optimization. A Portfolio Review of fields in the asset was held and this prioritized Field A among the top opportunities for further development. Seventy percent of oil volumes in the asset reside in 11 top fields and field A was a part of this category. The field has an expectation STOIIP of 1602.2 MMstb with ultimate recovery of 520.9 MMstb (RF 33%). The cumulative production from the field as estimated was 300 MMstb and expectation reserves was 89.5 MMstb, meaning an opportunity gap of 131 MMstb remains for which projects could be identified.

The field was selected for a Technical Review exercise due to its large STOIIP, low UR, depletion rate and decline in production. The review outcome identified gaps in data availability and volumes. A total of 40 opportunities were generated to mature70.1 MMbbl and as such optimising the life cycle ultimate recovery. This paper will highlight the process of efficient opportunity generation, its gains and effect on life cycle recovery using field A as a case study.
A Model for the Prediction of Hydrate Growth Initiation Point by Determining Quasi Liquid Layer Temperature
Authors: Oluwatoyin Akinsete O. , Obode Elizabeth I. , Ibadan Ibadan , Isehunwa Sunday O.
Published: July 2017

Hydrates constitute a major flow assurance challenge in the transportation of unprocessed gas through flowlines. Its undesirability stems from the fact that these solids reduce pipe diameter open to gas flow, challenge pipeline integrity, possibly leading to burst pipe – and increasing costs. Hydrates undergo four stages of maturation – entrainment, growth, agglomeration and plugging – and do not usually constitute a flow assurance challenge until agglomeration. These challenges are even more pronounced in the presence of gas-condensate in the flowline.

This paper proposes a model to predict the point in the flowline where hydrates start to form in the presence of gas-condensate. This is done by predicting the temperature at which quasi liquid layer starts to form on the hydrate seed. Quasi liquid layer refers to a film of pure water that forms around the hydrate seeds at a particular temperature drop within the system. When two seeds with this layer come together, they become joined together via capillary bridging – and the resulting crystal is bigger than the component seeds – thus leading to growth.

The developed analytical model relates mass of hydrate, length of the flowline, time taken for fluid flow in the system, the percentage of hydrate in the fluid composition, density of the hydrate, change in enthalpy and the velocity at which hydrate is flowing in the system to the temperature at which hydrates would start growing – that is the quasi liquid layer temperature.

The developed model was validated with field data, and the model was in agreement with field observations.
Harnessing Upstream Gas Resources for Power Generation in Nigeria: Issues, Strategies & Economics
Authors: Green Ovunda , Adeogun Oyebimpe , iledare Omowumi
Published: July 2017

Nigerian gas industry is gradually developing into an important sector of the nation's energy economy. Proved natural gas reserves is known to be substantially larger than oil potential in energy terms and it is estimated to be about 180Tcf.

Globally, natural gas has continued to displace other forms of fossil fuels for power generation due to its abundance, low carbon content and efficient technology. Gas, therefore presents the most viable option to bridge the existing gap between power generation capacity and demand in Nigeria. Despite Nigerian's huge potential in terms of gas resources and market, the gas sector is still plagued with perennial underdevelopment, principally caused by lack of clear fiscal regulatory framework and non market based gas pricing.

This paper, analyzes the economics of harnessing upstream natural gas for power generation using discounted cash flow model. Inputs for the model include a proposed PSC fiscal regime for offshore gas development; benchmark gas price for the power sector; cost estimates, production profile; discount and inflation rates. The estimated result in terms of the profitability indicator (NPV & IRR) and the discounted host government take (DHGT) shows the impact of the fiscal regime and gas price on profitability of upstream gas investment. IRR and NPV shows investment to be profitable at a base case gas price of $2.5/mcf. Further analysis carried out with respect to low, medium and high cost gas fields for associated and non-associated gas reveals that low and medium costs associated gas field and low cost non associated gas fields are profitable at a gas price of $2.5/mcf. Sensitivity analysis showed that high cost associated and non-associated gas fields are profitable at a gas price of $4.5/mcf. Stochastic analysis was also carried out to capture uncertainties associated with some variables used as input in the initial cash flow.
Prediction of Sand Production from Oil and Gas Reservoirs in the Niger Delta Using Support Vector Machines SVMs: A Binary Classification Approach
Authors: Olatunji Oladipo O. , Micheal Obolo
Published: July 2017

Sand production is one of the critical research subjects in the petroleum industry. In the oil and gas industry, the production of sand particles associated with the reservoir hydrocarbons has become one of the most common problems a well may experience during reservoir lifetime.

Sand production occurs in many fields across the world. This is easily seen in wells in the Niger Delta, Gulf of Mexico, Oman, Canada, Venezuela, Indonesia, Egypt, Trinidad and myriads of other places prolific to sanding. Managing sand production and ultimately its control in the oil and gas industry has been more or less a recurring problem. To fully understand the nature of sanding in an ingenuous way for sand control strategy, it is necessary to predict the conditions at which sanding occurs. Because so much have not been done in the implementation of the support vector machines for the prediction of the sanding onset in petroleum reservoirs, we are, for the first time, applying a robust approach, a binary classification problem approach for the prediction of sanding onset in petroleum reservoirs in the Niger Delta Region. By and Large, for the first time, the support vector machines (SVMs) classification approach, is used to identify whether sand will be produced or not in a hydrocarbon reservoir. The model presented in this paper takes into account different parameters (rock, fluid, geotechnical and other data) that may play a role in sanding. The performance of the proposed SVM model is verified using field data.

It is shown that the developed model can accurately predict the sand production in actual field conditions. The results of this study indicate that the implementation of SVM methodology can effectively help engineers to make a proactive sand control plan with insignificant impairment to hydrocarbon production from subsurface reservoirs.
Optimization Study on Inflow Control Devices for Horizontal Wells in Thin Oil Column Reservoirs: A Case Study of a Well in Niger Delta
Authors: Archibong Charles , Erhiaganoma Ese , Ikehi Emmanuel
Published: July 2017

Horizontal wells have been used to maximize recovery from thin pay reservoirs but this does not eliminate early water/gas breakthrough problem due to the presence of a non-uniform inflow along the completion. This uneven inflow is as a result of non-uniform pressure losses along the completion and instance reservoir heterogeneities. The non-uniform pressure losses causes higher flow rate and early break through from the heel sections than from the toe and the occasional presence of permeability variations creates zonal variations in water and/or gas encroachment.

Recent research efforts have led to the successful application of smart completions (Inflow Control Devices [ICDs] / Inflow Control Valves [ICVs]) to suppress the non-uniform inflow. The selection of optimal ICD configurations for such smart wells is normally obtained from a trial and error simulation with different configurations. A more recent study proposed a model for calculating optimal ICD strengths without flow simulations. The earlier solution with trial and error simulation is time consuming and the later solution with no flow simulation will not capture the influence of reservoir heterogeneities.

This paper presents the application of a new approach to ICD optimization in a horizontal well located offshore Niger Delta. The approach involves the development of a diagnostic algorithm which utilize results from a basecase simulation with an openhole horizontal well in order to determine the optimal ICD configuration for the well. The configuration parameters specified as optimization control variables in the algorithm include ICD strengths, the total number of ICDs in the wellbore and the valves density per ICD's compartment. A comparison of recoveries is made between an open-hole completion case, identical ICDs’ configurations case and the optimized ICDs case.

The case study is carried out with autonomous inflow control devices (AICDs) but the optimization's control variables are independent of the choice of ICD.
Determination of Wax Precipitation Tendency Using Sara Analysis
Authors: Mmata Bella , Ajienka Joseph , Onyekonwu Mike , Chukwu Godwin
Published: July 2017

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

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

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.