Numerical Simulations of Heterogeneous Chemical Reactions Coupled to Fluid Flow in Varying Thermal Fields

Numerical Simulations of Heterogeneous Chemical Reactions Coupled to Fluid Flow in Varying Thermal Fields PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 8

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Book Description
A numerical simulator of reactive chemical transport with coupling from precipitation-dissolution reactions to fluid flow, via changes of porosity and permeability, is applied to precipitation-dissolution of quartz and calcite in spatially and temporally variable fields of temperature. Significant effects on fluid flow are found in the quartz-silicic acid system in the presence of persistent, strong gradient of temperature. Transient heat flow in the quartz-silicic acid system and in a calcite-calcium ion-carbonato species system produces vanishingly small effects on fluid flow.

Numerical Simulations of Heterogeneous Chemical Reactions Coupled to Fluid Flow in Varying Thermal Fields

Numerical Simulations of Heterogeneous Chemical Reactions Coupled to Fluid Flow in Varying Thermal Fields PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 8

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Book Description
A numerical simulator of reactive chemical transport with coupling from precipitation-dissolution reactions to fluid flow, via changes of porosity and permeability, is applied to precipitation-dissolution of quartz and calcite in spatially and temporally variable fields of temperature. Significant effects on fluid flow are found in the quartz-silicic acid system in the presence of persistent, strong gradient of temperature. Transient heat flow in the quartz-silicic acid system and in a calcite-calcium ion-carbonato species system produces vanishingly small effects on fluid flow.

Energy Research Abstracts

Energy Research Abstracts PDF Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 438

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Book Description


Efficient Simulation of Thermal Enhanced Oil Recovery Processes

Efficient Simulation of Thermal Enhanced Oil Recovery Processes PDF Author: Zhouyuan Zhu
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 237

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Book Description
Simulating thermal processes is usually computationally expensive because of the complexity of the problem and strong nonlinearities encountered. In this work, we explore novel and efficient simulation techniques to solve thermal enhanced oil recovery problems. We focus on two major topics: the extension of streamline simulation for thermal enhanced oil recovery and the efficient simulation of chemical reaction kinetics as applied to the in-situ combustion process. For thermal streamline simulation, we first study the extension to hot water flood processes, in which we have temperature induced viscosity changes and thermal volume changes. We first compute the pressure field on an Eulerian grid. We then solve for the advective parts of the mass balance and energy equations along the individual streamlines, accounting for the compressibility effects. At the end of each global time step, we account for the nonadvective terms on the Eulerian grid along with gravity using operator splitting. We test our streamline simulator and compare the results with a commercial thermal simulator. Sensitivity studies for compressibility, gravity and thermal conduction effects are presented. We further extended our thermal streamline simulation to steam flooding. Steam flooding exhibits large volume changes and compressibility associated with the phase behavior of steam, strong gravity segregation and override, and highly coupled energy and mass transport. To overcome these challenges we implement a novel pressure update along the streamlines, a Glowinski scheme operator splitting and a preliminary streamline/finite volume hybrid approach. We tested our streamline simulator on a series of test cases. We compared our thermal streamline results with those computed by a commercial thermal simulator for both accuracy and efficiency. For the cases investigated, we are able to retain solution accuracy, while reducing computational cost and gaining connectivity information from the streamlines. These aspects are useful for reservoir engineering purposes. In traditional thermal reactive reservoir simulation, mass and energy balance equations are solved numerically on discretized reservoir grid blocks. The reaction terms are calculated through Arrhenius kinetics using cell-averaged properties, such as averaged temperature and reactant concentrations. For the in-situ combustion process, the chemical reaction front is physically very narrow, typically a few inches thick. To capture accurately this front, centimeter-sized grids are required that are orders of magnitude smaller than the affordable grid block sizes for full field reservoir models. To solve this grid size effect problem, we propose a new method based on a non-Arrhenius reaction upscaling approach. We do not resolve the combustion front on the grid, but instead use a subgrid-scale model that captures the overall effects of the combustion reactions on flow and transport, i.e. the amount of heat released, the amount of oil burned and the reaction products generated. The subgrid-scale model is calibrated using fine-scale highly accurate numerical simulation and laboratory experiments. This approach significantly improves the computational speed of in-situ combustion simulation as compared to traditional methods. We propose the detailed procedures to implement this methodology in a field-scale simulator. Test cases illustrate the solution consistency when scaling up the grid sizes in multidimensional heterogeneous problems. The methodology is also applicable to other subsurface reactive flow modeling problems with fast chemical reactions and sharp fronts. Displacement front stability is a major concern in the design of all the enhanced oil recovery processes. Historically, premature combustion front break through has been an issue for field operations of in-situ combustion. In this work, we perform detailed analysis based on both analytical methods and numerical simulation. We identify the different flow regimes and several driving fronts in a typical 1D ISC process. For the ISC process in a conventional mobile heavy oil reservoir, we identify the most critical front as the front of steam plateau driving the cold oil bank. We discuss the five main contributors for this front stability/instability: viscous force, condensation, heat conduction, coke plugging and gravity. Detailed numerical tests are performed to test and rank the relative importance of all these different effects.

Modeling and Simulation of Heterogeneous Catalytic Reactions

Modeling and Simulation of Heterogeneous Catalytic Reactions PDF Author: Olaf Deutschmann
Publisher: John Wiley & Sons
ISBN: 3527639888
Category : Science
Languages : en
Pages : 364

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Book Description
The Nobel Prize in Chemistry 2007 awarded to Gerhard Ertl for his groundbreaking studies in surface chemistry highlighted the importance of heterogeneous catalysis not only for modern chemical industry but also for environmental protection. Heterogeneous catalysis is seen as one of the key technologies which could solve the challenges associated with the increasing diversification of raw materials and energy sources. It is the decisive step in most chemical industry processes, a major method of reducing pollutant emissions from mobile sources and is present in fuel cells to produce electricity. The increasing power of computers over the last decades has led to modeling and numerical simulation becoming valuable tools in heterogeneous catalysis. This book covers many aspects, from the state-of-the-art in modeling and simulations of heterogeneous catalytic reactions on a molecular level to heterogeneous catalytic reactions from an engineering perspective. This first book on the topic conveys expert knowledge from surface science to both chemists and engineers interested in heterogeneous catalysis. The well-known and international authors comprehensively present many aspects of the wide bridge between surface science and catalytic technologies, including DFT calculations, reaction dynamics on surfaces, Monte Carlo simulations, heterogeneous reaction rates, reactions in porous media, electro-catalytic reactions, technical reactors, and perspectives of chemical and automobile industry on modeling heterogeneous catalysis. The result is a one-stop reference for theoretical and physical chemists, catalysis researchers, materials scientists, chemical engineers, and chemists in industry who would like to broaden their horizon and get a substantial overview on the different aspects of modeling and simulation of heterogeneous catalytic reactions.

Efficient Simulation of Thermal Enhanced Oil Recovery Processes

Efficient Simulation of Thermal Enhanced Oil Recovery Processes PDF Author: Zhouyuan Zhu
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Simulating thermal processes is usually computationally expensive because of the complexity of the problem and strong nonlinearities encountered. In this work, we explore novel and efficient simulation techniques to solve thermal enhanced oil recovery problems. We focus on two major topics: the extension of streamline simulation for thermal enhanced oil recovery and the efficient simulation of chemical reaction kinetics as applied to the in-situ combustion process. For thermal streamline simulation, we first study the extension to hot water flood processes, in which we have temperature induced viscosity changes and thermal volume changes. We first compute the pressure field on an Eulerian grid. We then solve for the advective parts of the mass balance and energy equations along the individual streamlines, accounting for the compressibility effects. At the end of each global time step, we account for the nonadvective terms on the Eulerian grid along with gravity using operator splitting. We test our streamline simulator and compare the results with a commercial thermal simulator. Sensitivity studies for compressibility, gravity and thermal conduction effects are presented. We further extended our thermal streamline simulation to steam flooding. Steam flooding exhibits large volume changes and compressibility associated with the phase behavior of steam, strong gravity segregation and override, and highly coupled energy and mass transport. To overcome these challenges we implement a novel pressure update along the streamlines, a Glowinski scheme operator splitting and a preliminary streamline/finite volume hybrid approach. We tested our streamline simulator on a series of test cases. We compared our thermal streamline results with those computed by a commercial thermal simulator for both accuracy and efficiency. For the cases investigated, we are able to retain solution accuracy, while reducing computational cost and gaining connectivity information from the streamlines. These aspects are useful for reservoir engineering purposes. In traditional thermal reactive reservoir simulation, mass and energy balance equations are solved numerically on discretized reservoir grid blocks. The reaction terms are calculated through Arrhenius kinetics using cell-averaged properties, such as averaged temperature and reactant concentrations. For the in-situ combustion process, the chemical reaction front is physically very narrow, typically a few inches thick. To capture accurately this front, centimeter-sized grids are required that are orders of magnitude smaller than the affordable grid block sizes for full field reservoir models. To solve this grid size effect problem, we propose a new method based on a non-Arrhenius reaction upscaling approach. We do not resolve the combustion front on the grid, but instead use a subgrid-scale model that captures the overall effects of the combustion reactions on flow and transport, i.e. the amount of heat released, the amount of oil burned and the reaction products generated. The subgrid-scale model is calibrated using fine-scale highly accurate numerical simulation and laboratory experiments. This approach significantly improves the computational speed of in-situ combustion simulation as compared to traditional methods. We propose the detailed procedures to implement this methodology in a field-scale simulator. Test cases illustrate the solution consistency when scaling up the grid sizes in multidimensional heterogeneous problems. The methodology is also applicable to other subsurface reactive flow modeling problems with fast chemical reactions and sharp fronts. Displacement front stability is a major concern in the design of all the enhanced oil recovery processes. Historically, premature combustion front break through has been an issue for field operations of in-situ combustion. In this work, we perform detailed analysis based on both analytical methods and numerical simulation. We identify the different flow regimes and several driving fronts in a typical 1D ISC process. For the ISC process in a conventional mobile heavy oil reservoir, we identify the most critical front as the front of steam plateau driving the cold oil bank. We discuss the five main contributors for this front stability/instability: viscous force, condensation, heat conduction, coke plugging and gravity. Detailed numerical tests are performed to test and rank the relative importance of all these different effects.

Catalytic Reactors

Catalytic Reactors PDF Author: Basudeb Saha
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110390124
Category : Technology & Engineering
Languages : en
Pages : 399

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Book Description
Catalytic Reactors presents several key aspects of reactor design in Chemical and Process Engineering. Starting with the fundamental science across a broad interdisciplinary field, this graduate level textbook offers a concise overview on reactor and process design for students, scientists and practitioners new to the field. This book aims to collate into a comprehensive and well-informed work of leading researchers from north America, western Europe and south-east Asia. The editor and international experts discuss state-of-the-art applications of multifunctional reactors, biocatalytic membrane reactors, micro-flow reactors, industrial catalytic reactors, micro trickle bed reactors and multiphase catalytic reactors. The use of catalytic reactor technology is essential for the economic viability of the chemical manufacturing industry. The importance of Chemical and Process Engineering and efficient design of reactors are another focus of the book. Especially the combination of advantages from both catalysis and chemical reaction technology for optimization and intensification as essential factors in the future development of reactors and processes are discussed. Furthermore, options that can drastically influence reaction processes, e.g. choice of catalysts, alternative reaction pathways, mass and heat transfer effects, flow regimes and inherent design of catalytic reactors are reviewed in detail. Focuses on the state-of-the-art applications of catalytic reactors and optimization in the design and operation of industrial catalytic reactors Insights into transfer of knowledge from laboratory science to industry For students and researchers in Chemical and Mechanical Engineering, Chemistry, Industrial Catalysis and practising Engineers

Scientific Basis for Nuclear Waste Management XV: Volume 257

Scientific Basis for Nuclear Waste Management XV: Volume 257 PDF Author: Claude G. Sombret
Publisher: Mrs Proceedings
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 784

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Book Description
The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.

Chemical Reactor Modeling

Chemical Reactor Modeling PDF Author: Hugo A. Jakobsen
Publisher: Springer Science & Business Media
ISBN: 3319050923
Category : Technology & Engineering
Languages : en
Pages : 1589

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Book Description
Chemical Reactor Modeling closes the gap between Chemical Reaction Engineering and Fluid Mechanics. The second edition consists of two volumes: Volume 1: Fundamentals. Volume 2: Chemical Engineering Applications In volume 1 most of the fundamental theory is presented. A few numerical model simulation application examples are given to elucidate the link between theory and applications. In volume 2 the chemical reactor equipment to be modeled are described. Several engineering models are introduced and discussed. A survey of the frequently used numerical methods, algorithms and schemes is provided. A few practical engineering applications of the modeling tools are presented and discussed. The working principles of several experimental techniques employed in order to get data for model validation are outlined. The monograph is based on lectures regularly taught in the fourth and fifth years graduate courses in transport phenomena and chemical reactor modeling and in a post graduate course in modern reactor modeling at the Norwegian University of Science and Technology, Department of Chemical Engineering, Trondheim, Norway. The objective of the book is to present the fundamentals of the single-fluid and multi-fluid models for the analysis of single and multiphase reactive flows in chemical reactors with a chemical reactor engineering rather than mathematical bias. Organized into 13 chapters, it combines theoretical aspects and practical applications and covers some of the recent research in several areas of chemical reactor engineering. This book contains a survey of the modern literature in the field of chemical reactor modeling.

NASA Tech Briefs

NASA Tech Briefs PDF Author:
Publisher:
ISBN:
Category : Technology
Languages : en
Pages : 106

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Book Description


Treatise on Process Metallurgy

Treatise on Process Metallurgy PDF Author: Alexander McLean
Publisher: Elsevier
ISBN: 0323854818
Category : Technology & Engineering
Languages : en
Pages : 858

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Book Description
Treatise on Process Metallurgy: Volume Four, Industrial Production provides academics with the fundamentals of the manufacturing of metallic materials, from raw materials into finished parts or products. In these fully updated volumes, coverage is expanded into four volumes, including Process Fundamentals, encompassing process fundamentals, structure and properties of matter; thermodynamic aspects of process metallurgy, and rate phenomena in process metallurgy; Processing Phenomena, encompassing interfacial phenomena in high temperature metallurgy, metallurgical process phenomena, and metallurgical process technology; Metallurgical Processes, encompassing mineral processing, aqueous processing, electrochemical material and energy processes, and iron and steel technology, non-ferrous process principles and production technologies, and more. The work distills the combined academic experience from the principal editor and the multidisciplinary four-member editorial board. Provides the entire breadth of process metallurgy in a single work Includes in-depth knowledge in all key areas of process metallurgy Approaches the topic from an interdisciplinary perspective, providing broad range coverage on topics