Day 1 Tue, August 11, 2020最新文献

{"title":"Modelling Minimum Flow Rate Required for Unloading Liquid in Gas Wells","authors":"A. Fadairo, G. Adeyemi, T. Ogunkunle, O. Lawal, Olugbenga Oredeko","doi":"10.2118/203683-ms","DOIUrl":"https://doi.org/10.2118/203683-ms","url":null,"abstract":"\u0000 Liquid loading in gas well has been an interest in the Oil and Gas sector due to the reduction of ultimate recovery and also the reduction of production from such wells. Several authors have presented various models for predicting the beginning of liquid loading in a gas well, yet there are regular errors in the model outcomes. Turner et al. based his critical model on a presumption that liquid droplet is spherical and stays that way throughout the wellbore. Li’s model developed later on based on his postulation that droplets are flat in shape and stays that way throughout the wellbore. In reality, when producing in a gas well, under pressure variation, the liquid droplets alternate between sphere-shape and flat shape. Hence there is a need to incorporate the liquid droplet deformation coefficient in the liquid loading governing equation. The newly presented model considered deformation coefficient to justify irregular changes in liquid droplet due to pressure variation during the simultaneous flow of gas and liquid droplet in gas wells, therefore, predict the critical flowrate correctly as the droplet fluctuates between spherical and flat shape. The results from the newly developed model of the critical flowrate using test data provided by Coleman et al. show that the modified critical flowrate is closer to the test flow rate than the other existing models as the error obtained is -9.12688%.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133930771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Chemical Modification of Calophyllum Inophyllum Plant Oil for Potential Base Oil in Drilling Mud Operation","authors":"C. Onuh, Dosunmu Adewale, Anawe A. L. Paul, Rotimi Oluwatosin","doi":"10.2118/203768-ms","DOIUrl":"https://doi.org/10.2118/203768-ms","url":null,"abstract":"\u0000 Research on the use of plant oil or ester oil in drilling mud operation is on the increase. The is due to the less toxic and low cost advantage over the commercial synthetic base oil. Despite the attractive physicochemical properties of vegetable oil samples, it deteriorates and becomes unstable under downhole temperature and aging conditions when used directly in mud formulation. Hence, plant oil needs improvement in order to be compared to the conventional base oil. Calophyllum inophyllum oil was extracted and reacted with methano in the presence of catalyst to form biodiesel. The physicochemical properties of the commercial synthetic base oil, extracted Calophyllum inophyllum oil, and biodiesel Calophyllum inophyllum oil were measured and compared to the EN14214 and the ASTM D6751 standards. The commercial synthetic oil, Calophyllum inophyllum oil, and biodiesel Calophyllum inophyllum oil had a flash point of 101 ± 0.1, 164 ± 0.1, and 146 ± 0.1 °C respectively; density of 108, 172, and 152 (kgm3) respectively; viscosity index of 192, 163, and 282 respectively; acid value of 0.953, 24.24, and 1.0 respectively, and oil yield of NA, 71, and 62 respectively. The result showed that the biodiesel can also serve as alternative to commercial synthetic base oil due to their comparable property to the commercial base oil. The biodiesel Calophullum inophyllum oil is a potential base oil for drilling mud formulation.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123945193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Case of Achieving Sustainable Annular Sealing in a Deepwater Marginal Nigerian Field","authors":"Mobolaji Musah, Benjamin Asokhia, Joseph Bagal, Dapo Adeniyi, Wai Hoe Chum","doi":"10.2118/203766-ms","DOIUrl":"https://doi.org/10.2118/203766-ms","url":null,"abstract":"The industry has been relying on cement as primary method for annular sealing. The initial evaluation considers a formation integrity test and a cement bond log. This shows good results in 85% of the cases and cement squeeze is the main remediation method. The ultimate measure of the sealing performance is production: more than 50% of the wells have sustained casing pressure in the B-annulus or are producing in degraded mode. Additional solutions are required to improve the sustainability of the industry.The present paper discusses a case history in a marginal well in Nigerian deepwater. Primary cement evaluation was successful, in line with the industry statistic of 85% successful cases. However, production started with 60% Basic Sediments and Water (BS&W) and after six months of production, the well was shut-in due to excessive gas production. The investigation identified that the target Turonian oil sand was separated by thin shales from bottom water and gas cap.In the sidetrack, two Well Annular Barrier (WAB) were used to augment the cement. The WAB is a metal-expandable packer that sets in open hole to assure sealing. One WAB was installed between the oil zone and the gas cap, and another one between the oil zone and the bottom water. The operation was successfully executed and the WABs expanded in wet cement after bumping the plug. Three years later, the well is still producing with 0.2% BS&W.This paper discusses the well conditions that contributed to insufficient cement sealing, the WAB application in the field, and the field results.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121708013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated Underreamer Technology with Real-Time Communication Helped Eliminate Rathole in Exploratory Operation Offshore Nigeria","authors":"Raphael Ozioko, Humphrey Osita, Udochukwu Ohia, E. Okafor","doi":"10.2118/203767-ms","DOIUrl":"https://doi.org/10.2118/203767-ms","url":null,"abstract":"\u0000 This paper describes the successful deployment of integrated underreamer technology with real-time communication through mud-pulse telemetry system, to drill and eliminate rathole in 17 1/2-in × 20-in successfully in one run and helped set casing as close as possible to the depth of suspected pressure ramp on an exploratory well offshore Nigeria. This technology uses the same communication system (actuator bypass) as Measurement While Drilling tools (MWD),Logging While Drilling tools (LWD) and Rotary Steerable System (RSS).\u0000 Integrated underreamers broadly used in the drilling operations support optimized casing and completion programs and helps reduce operational risks such as wellbore instability. The ball drop and hydraulically activated reamer technologies available today comes with limitations and HSE risks. The distinctive functionalities of the integrated underreamer technology described here, such as unlimited and fast activation and deactivation via downlinking and real time downhole feedback,reduce uncertainties and operational costs in the complex and challenging deep offshore drilling operations.\u0000 The real-time communication through mud-pulse telemetry system enabled the placement of integrated underreamer 6 meters from the bit thereby reducing rathole length to approximately 9 meters compared to 80 meters for conventional underreamer application. The integrated underreamer is compatible with existing RSS and provide unlimited activation cycles. The integrated underreamer offers flexibility in placement in the bottom hole assembly (BHA) and it can be used as a near bit reamer, or as main reamer or as both.In this case,the integrated near bit underreamer eliminated the need for a dedicated rathole removal run.It also offered a feedback confirmation of the cutter blades activation status and provided hole opening log thereby reducing the operational uncertainties for the under reaming, saving rig time up to 16 hours for shoulder test.\u0000 The underreamer was successfully deployed to drill and ream the challenging 14 ¾’’ × 17 ½’’ and ream 17 ½’’ × 20’’ section offshore Nigeria. Both sections were drilled and reamed to section Total Depth (TD) in one run with all directional requirements and Measurement While Drilling (MWD)/Logging While Drilling (LWD) met,saving client approximately 4 days of rig spread cost. The reamer appeared to provide an in-gauge borehole allowing for successful running and cementing of liners without any issues, demonstrating superior borehole quality.The new Technology proved to be a reliable and flexible hole enlargement while drilling solution that help to improve drilling performance, reduce operational risks and save cost.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131910455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Model for Predicting Elemental Sulphur Induced Permeability Damage in a Fractured Sour Gas Reservoir","authors":"G. Adeyemi, A. Fadairo, T. Ogunkunle, A. Oladepo, Amachree Alozie, R. Vamegh, Ling Kegang, Olugbenga Oredeko","doi":"10.2118/203750-ms","DOIUrl":"https://doi.org/10.2118/203750-ms","url":null,"abstract":"\u0000 The complexity and damages that result from the precipitation and deposition of hydrogen sulfide (H2S) in the sour gas reservoirs constitute challenges during modeling of gas production and transportation from such reservoirs. During production from a fractured gas reservoir with high H2S saturation, a continuous drop in the pressure is experienced within the formation. The change in pressure generally leads to a decline in the sulphur solubility and precipitation when it reaches its critical saturation state. Sulphur deposition in the pore spaces and throats of the formation rock eventually leads to porosity and permeability damage. It becomes paramount to have a model that depicts what happens in the formation throughout the life of the reservoir and to show the damage trend of the formation as the production time increases. In this current study, Robert's Sulphur deposition model was modified to account for non-darcy flow and fracture properties in the near-wellbore region. The results show that a decrease in fracture aperture lead to a decrease in the formation permeability. It also shows that higher production rate leads to increase in rate of sulphur deposition, and conclusively fracture aperture has a severe influence on the permeability of the formation as damage done in such reservoirs due to sulphur precipitation are more severe. It is advisable to maintain pressure above the critical pressure at which sulphur precipitation is activated, in order to maximize production and not to induce additional pressure drop caused by sulphur plugging on flow conduits.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116318779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing NAG Well Surveillance by Realtime Measurement of Condensate-Gas Ratio CGR Using Coriolis Meter","authors":"Chimdike Ihe, Uchenna Udobata, Ekine Ogbokuma, R. Maheshwari, Aref Arash, Uchenna Aja-Onu","doi":"10.2118/203674-ms","DOIUrl":"https://doi.org/10.2118/203674-ms","url":null,"abstract":"\u0000 Reliable gas well tests provide valuable data for production optimization and maximizing ultimate recovery of gas reserves. Poor data quality, heightened process safety risks and elevated OPEX are inherent limitations in the methods undertaken by operators to measure Condensate Gas Ratio (CGR) during Multi-Rate Tests (MRT) and routine production.\u0000 This paper describes the steps undertaken by the team in BERA to overcome this challenge by utilizing the density-measuring capability of the Coriolis meter. A density-based algorithm was setup using a designed decantation procedure and encoded in the control system for real-time measurements and made available in the office domain.\u0000 This technique provides improved data quality, ease of well surveillance and a long-term cost avoiding option while simultaneously increasing the flexibility and ease of executing MRTs. It eliminates the need for manual sampling with its associated process safety concerns.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124183957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Based Optimization for Natural Gas Dehydration and Glycol Regeneration","authors":"E. Okoro, S. Sanni, D. I. Olatunji, Paul Igbinedion, B. Oni, O. Orodu","doi":"10.2118/203751-ms","DOIUrl":"https://doi.org/10.2118/203751-ms","url":null,"abstract":"\u0000 Exergy is a simultaneous measure of the quantity and quality of energy. This helps to identify the inefficiency of the process and allows engineers to determine the cause and magnitude of the loss for each operating unit. Natural gas dehydration via absorption using glycol is the most economically attractive approach, and this advantage can only stand if lower energy consuption relative to adsorption process can be obtained; thus, timely prediction and identification of energy consumption is vital. In this study, an energy utilization predictive model for natural gas dehydration unit energy consumption was developed. This numeric approach will increase accuracy and reduce the high simulation time often encountered in using other simulation software. To achieve this novel idea, a multilayer perceptron approach which is a deep learning neural network model built on python using Tensorflow was adopted. The model used for this study is implemented to further increase the accuracy of the output set variables which are matched with simulation result. Since we are dealing with a non-linear function, rectified linear unit (ReLU) function was used to activate the neurons in hidden layers so as to strengthen the model to be more flexible in finding relationships which are arbitrary in the input parameter. These input parameters are fed into the steady state model and sent to various branches of fully connected neural network models using a linear activation function. Each branch produces a result for each output parameter thereby fitting the model by reducing the mean squared error loss. The training data were not normalized but left in their original form. Results showed that the adopted double hidden layer with 5 branches are uniquely branched in such a way that it predicts values for a single output variable, which is an upgrade to the former work done with a single hidden layer in literature. The accuracy analysis showed that the proposed double hidden layer approach in this study out-performed the single hidden layer.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"28 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116700104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crude Oil Price Risk Management: Should Nigeria Hedge Its Crude Oil Production?","authors":"Adedamola Adegun, O. Abiola","doi":"10.2118/203753-ms","DOIUrl":"https://doi.org/10.2118/203753-ms","url":null,"abstract":"\u0000 The volatility of the crude oil market and the uncertainties imposed on oil companies and oil producing nations is well documented. For National Oil Companies (NOCs) vested with the responsibility of managing their country's oil and gas resources and providing revenue needed for much investments, the unpredictability of the crude oil market poses more challenges. In Nigeria, oil price fluctuations constraint national and sub-national budgets as oil benchmarks are typically optimistic. From 2015 – 2019, actual revenue accretion from crude oil sales compared to benchmark price and production have been as low as fifty percent (50%) of target.\u0000 To address the uncertainties and guarantee stable revenue, it's imperative for Nigeria to implement best practice in crude oil price risk management by considering the merits and demerits of available tools such as hedging. A pertinent question is if hedging (similar to Mexico) a credible, beneficial option for Nigeria? Would hedging have improved Nigeria's revenue if adopted in the last five (5) years? This paper attempts to provide answers by analysing various hedging options and studying the success and downsides of major sovereign hedging programs.\u0000 We further explored the empirical and normative dynamics that will accelerate or impede the adoption of hedging and suggested mitigating options. We find that considering the empirical factors alone, crude oil price risk management is a potentially viable option for Nigeria as benefits extend beyond direct revenue increase. Hedging will instil discipline, confidence and ultimately attract investments into the Nigerian oil sector. Our conclusions nonetheless recognise that the soft, qualitative factors around hedging if not well managed could be a drawback, impacting revenues.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128174363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the Nexus Between Nigerian Rig Rates and Crude Oil Prices","authors":"K. Ojukwu, J. Ajienka, A. Dosunmu, O. Iledare, Chidi M. Ibe","doi":"10.14445/23939125/ijems-v7i2p111","DOIUrl":"https://doi.org/10.14445/23939125/ijems-v7i2p111","url":null,"abstract":"\u0000 This study set out to investigate how Nigerian oil rig rates respond to oil price fluctuations, and the lag between them aimed at developing models for forecasting land, swamp and offshore rigs rates in Nigeria.\u0000 The research methodology involves application of Ordinary Least Squares regression to develop models that can predict land, swamp and offshore rig rates, which can be used in the Nigerian market. Firstly, Brent crude oil prices are exogenous to Nigeria, whilst land, swamp or offshore rig rates are endogenous. Furthermore, these exogenous variables are regressed with and without lag to test the response time between the cause and its effect.\u0000 A striking relationship is observed between these independent variables similar to global trends. Like other countries, the Nigeria oilrigs count trends along with Brent crude oil price. However, a 3-4 months lag exists between Nigerian rig rates and oil prices. Furthermore, the model estimation using one-year lag seems to show more accuracy in matching the historical rig rates and the more expensive the rig, the wider the margin caused by oil price changes. This confirms the possibility to predict Nigeria rig rates and perhaps, well costs from oil price forecast.","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"17 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133106683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient Formation Testing and Data Interpretation Using Advanced Probes and In-Situ Fluid Property Evaluation","authors":"C. Khong, A. Robinson, G. Ostroff, S. Frank, James Dunlap, S. Roche, R. Jackson","doi":"10.2118/190800-MS","DOIUrl":"https://doi.org/10.2118/190800-MS","url":null,"abstract":"\u0000 Deepwater environments pose significant challenges in design and execution of comprehensive yet cost effective formation testing programs. For a recent deepwater appraisal well, pre-job modeling, advanced formation testing technologies, and in-situ fluid analysis were utilized to design and execute a formation testing program which provided significant improvement in the quality of data and fluid samples acquired, as well as significantly reduced time required for testing.\u0000 Multiple PVT and bulk samples were collected with an advanced focused sampling probe, providing an average pumping time of 3.5 hours per sampling depth with sample contamination as low as 1%. This compared favorably to nearly 9 hours per sample depth, double the volume of fluid pumped, and fluid contaminations of 8-14% observed in the previous appraisal well using an unfocused probe.\u0000 The low contamination improved the accuracy of real time Downhole Fluid Analysis (DFA) measurements such as density and viscosity, hydrocarbon composition and GOR performed with an advanced in-situ fluid analyzer. Fluorescence and reflectance detectors within the same tool were used to evaluate fluid phase state.\u0000 Another important component of the acquisition were several Interval Pressure Transient Tests (IPTT) performed to evaluate horizontal and vertical permeability. An advanced 3D radial probe was selected over a conventional Dual Packer to perform these tests. The 3D radial probe was more time-efficient, provided better quality buildup data including vertical interference data (VIT), and presented lower operational risk. Real time measurement of fluid viscosity enabled the immediate estimation of permeability. Zonal permeability and permeability anisotropy (kv/kh) for the tested intervals were interpreted from the pressure transient responses of the radial probe and observation probe","PeriodicalId":325291,"journal":{"name":"Day 1 Tue, August 11, 2020","volume":"18 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131487200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}