SPE Production & Operations最新文献

{"title":"Unified Modeling of Pseudo-Slug and Churn Flows for Liquid Holdup and Pressure Gradient Predictions in Pipelines and Wellbores","authors":"Y. Fan, M. Aljasser","doi":"10.2118/212863-pa","DOIUrl":"https://doi.org/10.2118/212863-pa","url":null,"abstract":"\u0000 Pseudo-slug flow is a coherent flow pattern that occurs in horizontal or inclined pipes surrounded by segregated and conventional slug flows. Recent studies have demonstrated that this flow pattern can occupy a large area in the flow pattern map and cannot be simply ignored. Churn flow commonly occurs in upward vertical or slightly deviated wellbores characterized by a chaotic intermittent flow behavior. Pseudo-slug and churn flows are generally considered as two different flow patterns mainly because of their visual differences. However, some recent studies have shown that they share many similarities. There are several hydraulic models for churn flow, and the models for pseudo-slug flow have also emerged in recent years. However, these models only work for a certain inclination angle range, and none work for both flow patterns. This paper proposes a new unified hydraulic model that is applicable for both flow patterns. The liquid holdup prediction is based on the drift-flux model, while the pressure gradient is predicted using a two-fluid model that considers wall frictions from both gas and liquid phases. The new model better captures the effects of gas and liquid flow rates, gas density, liquid viscosity, inclination angle, and pipe diameter on the liquid holdup and pressure gradient compared with other models. Model evaluations show that the new model gives the best predictions compared with other available pseudo-slug or churn models. The new model reduces the total average absolute relative error to 14.0% for the liquid holdup prediction and 19.1% for the pressure gradient prediction.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121088918","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 Complete Model for Mesh Pad Mist Eliminators in Oil and Gas Processing by Analogy with Distillation Packing","authors":"Charles Logan Grim, Ahmed Al-Zubail","doi":"10.2118/212862-pa","DOIUrl":"https://doi.org/10.2118/212862-pa","url":null,"abstract":"\u0000 Current models for pressure drop in mesh pads are not adequate for pressure drop critical applications and do not cover the flooding regime commonly encountered when mesh pads are used as a coalescer. In addition, these models do not predict the flooding capacity of mesh pads. Pressure drop and capacity models for mesh pads are presented and compared with literature experimental data for fluid systems ranging from atmospheric pressure to 85-bar natural gas. The experimental data were successfully correlated from the region of countercurrent flow through to flooding of the mesh pads. The model captures, quantitatively, the pressure drop and liquid holdup in mesh pads as well as predicting the flood point of the mesh. When combined with a separation performance method, flooding in layered mesh pads can also be predicted. The model covers both conventional and co-knit mesh pads and can be adapted to other packing geometries, requiring only dry pressure drop data.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116221621","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":"An Integrated Review on Asphaltene: Definition, Chemical Composition, Properties, and Methods for Determining Onset Precipitation","authors":"M. A. Ahmed, G. Abdul-Majeed, Ali K. Alhuraishawy","doi":"10.2118/212310-pa","DOIUrl":"https://doi.org/10.2118/212310-pa","url":null,"abstract":"\u0000 Asphaltene is a solid oil component with a wide range of molecular compositions and structures, making it one of oil’s most complicated components. The deposition and precipitation of asphaltene in several places along the oil production line, such as the wellbore, reservoir, flow lines, tubing, and the separation unit at the surface, of the most prevalent flow assurance challenges. Changes in pressure, composition, and temperature cause asphaltene to precipitate out of the oil continuum. Variations in operation condition are caused by various recovery processes (gas injection, natural depletion, and chemical injection) in addition to the creation and blending of various oils during transportation. This paper presents a complete review of asphaltene precipitation (AP) and deposition (AD), which in turn helps in understanding the governing mechanisms and thermodynamic behaviors in this field. This study consists of several stages: analyzing the current state of asphaltene research (asphaltene characteristics, chemical nature, molecular structure, asphaltene crude oil phase behavior, solubility factors, and other factors); describing the phases of asphaltene (from its stability through its deposition in the reservoir pores, facilities, wellbore path in addition to the reasons for their occurrence); clarifying the rheology and asphaltene flow behavior in the reservoir; and finally examining the advantages and disadvantages of most widely used strategies for determining onset AP. In addition, some measured Iraqi asphaltene data are demonstrated and analyzed. This work will contribute to better knowledge of asphaltene and will serve as a reference for future studies on how to properly investigate and simulate asphaltene.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132246258","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":"An Insight into the Prediction of Scale Precipitation in Harsh Conditions Using Different Machine Learning Algorithms","authors":"Reza Yousefzadeh, A. Bemani, A. Kazemi, Mohammad Ahmadi","doi":"10.2118/212846-pa","DOIUrl":"https://doi.org/10.2118/212846-pa","url":null,"abstract":"\u0000 Scale precipitation in petroleum equipment is known as an important problem that causes damages in injection and production wells. Scale precipitation causes equipment corrosion and flow restriction and consequently a reduction in oil production. Due to this fact, the prediction of scale precipitation has vital importance among petroleum engineers. In the current work, different intelligent models, including the decision tree, random forest (RF), artificial neural network (ANN), K-nearest neighbors (KNN), convolutional neural network (CNN), support vector machine (SVM), ensemble learning, logistic regression, Naïve Bayes, and adaptive boosting (AdaBoost), are used to estimate scale formation as a function of pH and ionic compositions. Also, a sensitivity analysis is done to determine the most influential parameters on scale formation. The novelty of this work is to compare the performance of 10 different machine learning algorithms at modeling an extremely non-linear relationship between the inputs and the outputs in scale precipitation prediction. After determining the best models, they can be used to determine scale formation by manipulating the concentration of a variable in accordance with the result of the sensitivity analysis. Different classification metrics, including the accuracy, precision, F1-score, and recall, were used to compare the performance of the mentioned models. Results in the testing phase showed that the KNN and ensemble learning were the most accurate tools based on all performance metrics of solving the classification of scale/no-scale problem. As the output had an extremely non-linear behavior in terms of the inputs, an instance-based learning algorithm such as the KNN best suited the classification task in this study. This argumentation was backed by the classification results. Furthermore, the SVM, Naïve Bayes, and logistic regression performance metrics were not satisfactory in the prediction of scale formation. Note that the hyperparameters of the models were found by grid search and random search approaches. Finally, the sensitivity analysis showed that the variations in the concentration of Ca had the highest impact on scale precipitation.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"2012 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127402525","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 Mechanistic Model for the Two-Phase Slug Flow of the Purely Viscous Non-Newtonian Liquids through Pipes","authors":"M. G. Ramirez, D. Cruz, F. Nikfarjam, H. Anbarlooei","doi":"10.2118/212838-pa","DOIUrl":"https://doi.org/10.2118/212838-pa","url":null,"abstract":"\u0000 Mechanistic slug models generally depend on several empirical correlations. This work presents an extended model, which incorporates a recently theoretically developed family of friction equations for purely viscous non-Newtonian fluids to reduce this dependency. In contrast to other models where a fixed transition Reynolds number is used, a proper rheology-dependent laminar-to-turbulent transition criteria has been adopted. Finally, to fully specify the characteristics of the slug flow, a new model is introduced for the slug frequency, by balancing the pressure forces and the drag over the gas bubble. The resulting model requires just one empirical coefficient, drag coefficient of the bubble, which depends on the rheology of the fluids and diameter of the pipe. The developed models have been extensively verified with the experimental data, for the two-phase flows with Newtonian and non-Newtonian (power law and Bingham) liquid phase. Our mechanistic model predicts the pressure drop of the experimental data within ±20% error range, while it does not introduce any new empirical coefficient for the non-Newtonian case. This model, besides its simplicity and accuracy, successfully captures the physical trends in experimental data where other available models fail. The frequency model with calibrated drag coefficient reproduces the experiments with less than 30% error, while one can find a universal drag coefficient which can reproduce most of the experimental observations within the same error range. To summarize, the proposed models can fully characterize two-phase slug flows in presence of a non-Newtonian purely viscous fluid phase.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"15 12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127634229","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":"Analysis of Perforation Erosion Through Computational Fluid Dynamic Modeling","authors":"Yiming Zhang, J. Wang","doi":"10.2118/212845-pa","DOIUrl":"https://doi.org/10.2118/212845-pa","url":null,"abstract":"\u0000 Field and experimental data have shown that perforation erosion during shale gas stimulation invalidates the assumption of a constant coefficient of discharge. However, perforation erosion is not fully understood yet. In this work, a perforation erosion model was built using computational fluid dynamics (CFD) and validated against laboratory data. We then conducted parametric studies to investigate the impact of treatment rate, proppant concentration, proppant size, and fluid viscosity on perforation erosion. Our results demonstrated that a higher treatment rate and larger proppant lead to higher erosion to the perforation diameter. Perforation erosion decreased when fluid viscosities increased from 10 to 100 cp, and then increased when the fluid viscosity was increased to 1,000 cp. Our new understandings could be applied to improve perforation design in shale wells.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"141 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127299035","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":"Propagating Hydraulic Fractures from Wellbores: Effects of In-Situ Stress and Near-Wellbore Stress Redistribution","authors":"Q. Gao, De-sheng Zhou, A. Ghassemi, Xiong Liu, Yafei Liu, Min Guo","doi":"10.2118/212850-pa","DOIUrl":"https://doi.org/10.2118/212850-pa","url":null,"abstract":"\u0000 As a mature technology to enhance the permeability of geological formations, hydraulic fracturing has widely been used in geothermal energy development and in the petroleum industry. Due to its effectiveness in practical applications, it attracts many research efforts. Because of the complexity of hydraulic fracturing itself and the complex distribution of stresses around wellbores, accurately describing the behaviors of hydraulic fractures is still a challenging task. In this study, a numerical model is developed to simulate curved propagation of hydraulic fractures from a wellbore, and emphases are placed on influence of in-situ stress and near wellbore stress redistribution.\u0000 In the developed hydromechanical model, special considerations are given to its ability to simulate curved propagation of hydraulic fractures. The propagation of fractures is modeled through the phase-field method. Several cases on hydraulic fracture initiation and propagation from horizontal wellbores are studied through the proposed model. The model has been successfully verified through analytical solutions. The influence of stress redistribution caused by wellbore pressurization on hydraulic fracture initiation from wellbores is analyzed. Under different in-situ stress configurations and initial fracture orientations (perforation or flaws around wellbores are represented by the initial fractures), several patterns of hydraulic fracture propagation around the wellbores are recognized. It is found that the stress redistribution in the close vicinity of wellbores has great influences on the fracture initiation and propagation, and it makes hydraulic fractures propagate in nonplanar, complex manners. As hydraulic fractures propagate away from the stress redistribution regions around the wellbores, in-situ stress then determines the directions of fracture propagation; the curvature of fracture growth paths is mainly determined by the difference in in-situ stress, for example, σv − σhmin in this study. It has also been demonstrated that, when analyzing fracture propagation from wellbores, the wellbore stability or nonlinear deformation of a wellbore should be considered together with the fracture propagation conditions.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130033035","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":"Unlocking the Potential of Acid Stimulation in Volcanic Rocks: A Successful Case with Integrated Analysis in Minami-Nagaoka Gas Field, Japan","authors":"N. Yoshida, Keisuke Shimoda, Keisuke Yamamura, K. Fuse, Haruki Kaminoyama, Y. Ishigami, A. Mhiri, Li Niu, P. Ramondenc, Yin Luo, Wei Liu","doi":"10.2118/212307-pa","DOIUrl":"https://doi.org/10.2118/212307-pa","url":null,"abstract":"\u0000 Acid stimulation of volcanic formations is rarely documented in the literature. A recent study however suggested its potential effectiveness through a comprehensive laboratory/modeling analysis and documented substantial permeability enhancement by dissolution of carbonate-cemented fractures in the near-wellbore area to create wormhole-like high-permeability channels. The study also presented a brief description of successful field execution, although operational details and analysis of results were not presented.\u0000 This work presents in detail the field case of a multistage acidizing treatment in the Minami-Nagaoka gas field, a volcanic reservoir, and demonstrates the effectiveness of acid stimulation with 10% formic acid for productivity enhancement. The selection of a target well relies on the abundance of cemented fractures along a well. The operational design considers multiple field/well characteristics, such as low permeability; long, perforated intervals; and high-temperature conditions. Effectiveness of acid stimulation is evaluated comprehensively and justified by the integration of real-time stimulation diagnostics using distributed temperature sensing (DTS), real-time surveillance of bottomhole key parameters obtained thanks to coiled-tubing (CT) fiber-optic downhole telemetry, pre-/post-acidizing pressure buildup (PBU) tests, and production logging tool (PLT) surveys.\u0000 A multistage acidizing operation was executed, after completion of a step-rate test during which a pre-acidizing DTS survey was acquired. Eight stages of 10% formic acid injection and seven stages of degradable particulate diverter placement were pumped, followed by brine displacement and a post-acidizing DTS acquisition. In all the stages, acid injection decreased the bottomhole pressure while the use of diverter increased it (by hundreds of psi), thus indicating success in acid stimulation and diversion, respectively. The stimulation almost doubled the gas flow rate just after the operation, and 10 months after the operation, the gas rate is still 1.5 times higher than before intervening. Pre-/post-acidizing PBU tests suggested a substantial reduction of the skin from 1.50 to −1.91. DTS surveying identified one major and three minor fluid-intake intervals through stimulation/diversion, and integrated analysis with PLTs revealed that the substantial improvement in gas rate was primarily coming from a narrow zone located within the major intake interval, where resistive fractures are abundant. The current case demonstrates the effectiveness of 10% formic acid for the stimulation of rocks with carbonate-cemented fractures, which was also proposed by the former study. It also shows that there is still room for further optimization in the operational design.\u0000 This paper provides insights on acid stimulation in volcanic rocks and highlights its effectiveness through the analysis of a series of data sets. Readers may obtain knowledge on acidizing design, the evaluation of ","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"180 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124513178","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":"Study on Synergistic Demulsification Mechanism of Microwaves and Ionic Liquids on Heavy Oil Emulsions","authors":"Huayi Jiang, Ding Wang, N. Sun, Ruiyu Su, Jianbo Hu","doi":"10.2118/212312-pa","DOIUrl":"https://doi.org/10.2118/212312-pa","url":null,"abstract":"\u0000 Heavy oil-in-water (O/W) emulsions must be treated before refinement and transportation, and microwave and ionic liquid (IL) synergistic effects are stable, efficient, and environmentally friendly methods of demulsification. In this study, the synergistic effects of various IL anion and cation types and concentrations upon microwave emulsion demulsification were investigated. The interfacial tension (IFT) and zeta potential of the ILs and the distribution of oil droplets were measured before and after microwave radiation using a spinning drop tensiometer, zeta potential analyzer, and biological microscope to elucidate the synergistic mechanism of microwave and IL demulsification. The results indicate that microwave radiation parameters that are set too high or low can have an inhibitory effect on demulsification. When [C16MIM]Br with a concentration of 1 mmol/L was used as the IL, and the microwave radiation parameters were set to 300 W for 30 seconds, the demulsification efficiency reached 89.29%, which was 3.23 times and 2.08 times higher than the individual demulsification efficiency of microwave radiation and IL, respectively. This study provides a novel approach for examining high-performance demulsification, and it extends the applicability of microwave-IL synergy.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"196 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132719058","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 Comparative Study of the Cubic-Plus-Association Equation of State and a Peng-Robinson Equation of State–Based Solid Model for Asphaltene Simulation in the Wellbore","authors":"F. Coelho, R. Okuno, K. Sepehrnoori, O. Ezekoye","doi":"10.2118/212293-pa","DOIUrl":"https://doi.org/10.2118/212293-pa","url":null,"abstract":"\u0000 Asphaltene is one of the main flow-assurance concerns in oil production. Its precipitation and further deposition along the flow path (wellbore or reservoir) can cause reduced hydrocarbon flow rates and even a total blockage. These potential damages have caused a growing interest in computationally efficient methods to predict asphaltene precipitation, depending on flow conditions.\u0000 This paper presents two different approaches: (i) a model from Li and Firoozabadi (2010), using a simplified version of the cubic-plus-association equation of state (CPA EOS), and (ii) a version of a solid model based on the Peng-Robinson (PR) EOS, with no association term. The two approaches are compared in isolated flash calculations and wellbore flow simulations with asphaltene deposition. The comparisons are made using the same fluid parameters for both approaches as much as possible.\u0000 Results show that, if provided with adequate input data, the solid model can consistently match results from the more complex CPA model quite successfully for several fluid compositions. An attempt is made to explain the “success” of the solid model in reproducing CPA model results. The solid model cannot adjust to fluid-composition changes in a manner similar to that of CPA. Therefore, the solid model seems more suitable for wellbore than reservoir simulation, which tends to involve a higher level of fluid mixing. However, the efficiency of the solid model can reduce the computational time by a factor of 2 in comparison with CPA.","PeriodicalId":153181,"journal":{"name":"SPE Production & Operations","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115209264","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}