Download or read book Kinetics of Gasification of Coal Chars at High Pressure written by Stuart Maxwell and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetics of Coal Gasification written by James L. Johnson and published by John Wiley & Sons. This book was released on 1979-12-20 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides the best description of coal gasification reactions available today, presenting a series of publications by the late James Lee Johnson that trace his work on the development of coal gasification kinetics. Puts gasification kinetics into perspective for reactor design by discussing gasification thermodynamics, fluidized beds, and the physical characteristics of coals and coal chars for estimating this gasification reactivity. An outstanding reference based on a chaper contributed by Dr. Johnson to CHEMISTRY OF COAL UTILIZATION SUPPLEMENTARY VOLUME 2 (edited by Martin A. Elliot).
Download or read book Evaluation of Coal Char Gasification Kinetics and Pore Development in High Pressure Steam and Carbon Dioxide written by and published by . This book was released on 2020 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: High pressure steam and CO2 gasification kinetics -- Intrinsic reaction rates -- Pore development -- Highveld coal char.
Download or read book Gasification Kinetics and Pore Development of a Highveld Coal Char at High Pressures written by S. F. Conradie and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Final year report -- Chemical and Minerals Engineering.
Download or read book Structural Characteristics and CO2 Reactivity of Partially Gasified Pittsburgh No 8 Coal Chars Generated in a High pressure High temperature Flow Reactor written by Vijayaragavan Krishnamoorthy and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrated gasification combined cycle (IGCC) is an advanced power generation technology based on gasification of coal or solid fuels. Despite many commercial operations, the knowledge of char gasification rates at high pressures and temperatures, crucial to the design and troubleshooting of the gasifiers, are relatively unknown. While many kinetic studies have been performed at atmospheric pressure and low heating rates, there are few studies that examined the reactivity of chars generated at high temperatures and elevated pressuresGasification rate of chars in entrained-flow gasifiers is dependent on both intrinsic reactivity and the gas diffusion rate of reactants into pores. Therefore, the knowledge of intrinsic reaction rate and the structural features of the char are necessary for developing a kinetic model. The aim of the thesis is to determine the intrinsic reactivity and the structural features of the chars generated at elevated pressures and temperatures pertinent to conditions of the entrained-flow gasifiers. A series of interrelated studies were conducted to characterize the gasification behavior of a widely used Pittsburgh No,8 coal. To generate chars under conditions similar to that of the gasifier, a 20 kW high-pressure, high-temperature flow reactor (HPHTFR) was designed to operate up to 1650C and 30 bar. The chars obtained at various temperatures, pressures, and pyrolysis atmospheres were characterized for physical and chemical structure using surface area analyzer, XRD, Raman, and morphological analysis. The CO2 kinetics on chars were obtained using a high pressure thermogravimetric analyzer (HPTGA). The structural properties and intrinsic kinetics of chars widely reported in the literature were generated in inert atmospheres. However, the pyrolysis of feedstock occurs in the presence of reaction gas. This difference can affect char structural properties and intrinsic reactivity. To determine the role of pyrolysis atmosphere, chars were generated in three different atomspheres-CO2/N2, Ar and N2- at 1100C and 6.2 bar. The chars generated in the CO2/N2 atmosphere showed higher conversion compared to that of chars generated in N2 and Ar atmospheres. The increased conversion in the CO2/N2 atmosphere was attributed to increased gasification of tar/soot. While the volatile yield showed some difference, char properties such as surface area, swelling ratio, defects to graphitic band ratio and crystallite sizes showed no difference. The kinetic parameters of the chars were obtained using the nth order model. The activation energy was found to be independent of pyrolysis atmospheres. The order of reaction was found to be significantly affected by the pyrolysis atmosphere. The order of reaction followed the trend: CO2/N2> N2 Ar. The order of the reaction was found to correlate with surface area evolution.Gasification of coal can be impacted by the organic and inorganic compositional heterogeneity, which further impact the char morphology, and the intrinsic reactivity. To account for the compositional heterogeneity, chars were generated from various size fractions (-106+75, -150+106, -212+150, -420+212 m at 1300C and 11.3 bar) and density fractions (1.3 g/cc, 1.3-1.6 g/cc, 1.6g/cc of -106+75 m at 1300C and 11.3 bar). Chars were also generated over a range of temperatures (1100, 1300, and 1400C at 11.3 bar for the -150+106 m fraction), pressures (3.4, 6.2, 11.3, 15.5, and 21.7 bar at 1300C for -150+106 m fraction) to study the effect of temperature and pressure on char structures and reactivity. Chars were characterized for morphology, pore structure (i.e. surface area and pore volume), reflectance, and reactivity using oil immersion microscopy, N2 adsorption technique, reflectance microscopy, and thermogravimetric analyzer, respectively. The swelling ratio, pore volume, and surface area increased up to certain pressure while these parameters decreased with particle size and density fraction. The intrinsic reactivity of chars increased with inorganic matter and feed particle size, while it decreased with increase in char generation temperature. The intrinsic gasification rate is an important parameter for designing a kinetic model. Chars were obtained by partially gasifying Pittsburgh No.8 coal in CO2 atmosphere at 1300C and over a range of pressures (3.4, 6.2, 11.3, 15.5, and 21.7 bar) in the HPHTFR. The intrinsic reaction rate of those chars with CO2 was obtained at the char generation pressure using the HPTGA. The kinetic parameters were obtained using the nth order model. The intrinsic reaction rate, and activation energy were found to be independent of the char generation pressure. The order of reaction was obtained by varying CO2 partial pressures. The order of reaction decreased with increase in char generation pressure. The comparison of initial char with the char obtained at ~20% conversion in the HPTGA for surface area and pore volume showed that the reaction primarily occurs in microporous regions. The order of reaction also closely followed the surface area during gasification in the HPTGA.Through this research, a comprehensive assessment of the entrained-flow gasification behavior of Pittsburgh No.8 coal has been performed using proven experimental techniques under conditions of industrial interest. The structural features and kinetics were obtained. The generated data provide optimum, and trends that can be used as direct inputs to kinetic modelling and gasifier design applications.
Download or read book Investigation of High temperature and High pressure Steam Gasification Kinetics of a Coal derived Char Surrogate written by Madison A. Kelley and published by . This book was released on 2017 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biomass Gasification and Pyrolysis written by Prabir Basu and published by Academic Press. This book was released on 2010-07-19 with total page 377 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers comprehensive coverage of the design, analysis, and operational aspects of biomass gasification, the key technology enabling the production of biofuels from all viable sources--some examples being sugar cane and switchgrass. This versatile resource not only explains the basic principles of energy conversion systems, but also provides valuable insight into the design of biomass gasifiers. The author provides many worked out design problems, step-by-step design procedures and real data on commercially operating systems. After fossil fuels, biomass is the most widely used fuel in the world. Biomass resources show a considerable potential in the long term if residues are properly handled and dedicated energy crops are grown. Includes step-by-step design procedures and case studies for Biomass GasificationProvides worked process flow diagrams for gasifier design. Covers integration with other technologies (e.g. gas turbine, engine, fuel cells)
Download or read book Kinetics of Coal Gasification at High Pressure written by Terence William Albert Rampling and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Kinetics of Combustion and Gasification of Some Coal Chars written by D. T. Trangmar and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gas Solid Reactions written by Julian Szekely and published by Elsevier. This book was released on 2012-12-02 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas-Solid Reactions describes gas-solid reaction systems, focusing on the four phenomena—external mass transfer, pore diffusion, adsorption/desorption, and chemical reaction. This book consists of eight chapters. After the introduction provided in Chapter 1, the basic components of gas-solid reactions are reviewed in Chapter 2. Chapter 3 describes the reactions of individual nonporous solid particles, while Chapter 4 elaborates the reaction of single porous particles. Solid-solid reactions proceeding through gaseous intermediates are considered in Chapter 5. Chapter 6 deals with the experimental approaches to the study of gas-solid reaction systems. How information on single-particle behavior may be used for the design of multiparticle, large-scale assemblies, and packed- and fluidized-bed reaction systems is deliberated in Chapter 7. The last chapter covers the specific gas-solid reaction systems, including some statistical indices indicating the economic importance of the systems and processes it's based on. This publication is recommended for practicing engineers engaged in process research, development, and design in the many fields where gas-solid reactions are important.
Download or read book The Science of Victorian Brown Coal written by R.A. Durie and published by Butterworth-Heinemann. This book was released on 2013-10-22 with total page 767 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Science of Victorian Brown Coal provides extensive information on Victorian brown coal, which is a major fossil fuel resource by any standard and constitutes about 97% of Victoria's recoverable energy reserves. Energy from brown coal has been the mainstay of the Victorian economy, providing low-cost electricity to the state grid, briquettes as a fuel for industry and town gas prior to the discovery of natural gas. Because of the unique properties of the coal, it has been necessary to develop an in-depth scientific knowledge of the coal and its behavior, as well as innovative technologies for its effective utilization. The economic benefit brown coal has provided to Victoria is demonstrated throughout the chapters. This book aims to provide the springboard for further research and lead to a new era in the development of value-added products and the more efficient utilization of this major resource. This text is a useful reference for students or individuals conducting research on fossil fuel energy, specifically on brown coals.
Download or read book Fundamental Issues in Control of Carbon Gasification Reactivity written by L. Lahaye and published by Springer Science & Business Media. This book was released on 1991-01-31 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last decade there has been a renewed interest in under standing from a fundamental point of view the gasification of carbon. Basi cally there are two major issues in controlling the reactivity of carbon: i) reduction of the gasification rate of carbon materials in hostile environment ii) increase of the gasification rate in order to utilize carbonaceous compounds more effectively. Although these two objectives look somewhat contradictory, they are part of the general topics of understanding gasification reactivity of carbon. Refractory applications of carbon in furnace linings, seals and vanes, as well as the use of carbon-carbon or carbon-ceramic composites in struc tures able to withstand corrosion at high temperature require a better understanding of the fundamentals involved in carbon-oxidizing gas (02' CO , H 0) reactions. Furthermore a great interest of aluminium producers 2 2 is 10 extending the lifetime of carbon electrodes in alumina electrolysis which primarily depends on reducing their consumption rates by air or carbon dioxide. Proper control of gasification reactions is also of prime importance in manufacturing carbonaceous adsorbents like granular activated carbon clothes of high adsorption characteristics. The balance between increase of porosity and decrease in mechanical strength during activation is critical for developing new porous types of carbon materials in particular for carbon clothes and this can only be achieved by a careful control of the gasification reaction.
Download or read book Kinetics of Char Gasification Reactions Under Conditions of Underground Coal Gasification written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This project is directed toward support studies for the national endeavor on in situ coal gasification. The objective is to determine reaction-controlling variables and reaction kinetics for gasification of chars resulting from pyrolysis of coal in underground gasification. The data obtained from these studies are used in the mathematical modeling of in situ gasification systems, in order to understand and interpret field experimental data and to design future field studies. The reactions being studied include steam-char, CO/sub 2/-char, and water gas shift reactions, as well as methane-producing reactions such as the methanation of CO or the hydrogen-char reaction. The kinetics studies are carried out in a packed bed differential reactor in which steam, H/sub 2/, CO/sub 2/, and/or other reactants are blended with N/sub 2/ to obtain the desired total pressure and partial pressures of reactants. The preparation of the char is carried out immediately prior to gasification in the reactor under conditions of pressure, heating rate, and sweeping gas composition similar to those encountered in underground gasification. The coals studied include Wyodak and Hanna subbituminous coals and Pittsburgh seam high volatile bituminous coal. Kinetic data are reported for the reaction of steam with chars prepared from the Wyodak and Hanna coals. The dependence of the reaction rate on the partial pressures of reactant steam and product hydrogen is described. The temperature dependence of the reaction rates indicates that diffusion of reactants and products through pore structure of Hanna char limits the reaction more severely than in the case of the Wyodak char. The rate of reaction of steam with Wyodak char is approximately 50% greater than the rate observed with the Hanna char. The reaction order with respect to steam at low partial pressures of steam varies from 0.5 to approximately 1. Preliminary information is also reported for reaction of steam with chars prepared from Pittsburgh seam coal.
Download or read book Gasification for Synthetic Fuel Production written by R Luque and published by Elsevier. This book was released on 2014-08-29 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gasification involves the conversion of carbon sources without combustion to syngas, which can be used as a fuel itself or further processed to synthetic fuels. The technology provides a potentially more efficient means of energy generation than direct combustion. This book provides an overview of gasification science and engineering and the production of synthetic fuels by gasification from a variety of feedstocks. Part one introduces gasification, reviewing the scientific basis of the process and gasification engineering. Part two then addresses gasification and synthentic fuel production processes. Finally, chapters in part three outline the different applications of gasification, with chapters on the conversion of different types of feedstock. - Examines the design of gasifiers, the preparation of feedstocks, and the economic, environmental and policy issues related to gasification - Reviews gasification processes for liquid fuel production - Outlines the different applications of gasification technology
Download or read book The Kinetics of the Carbon Dioxide coal Char Gasification Reaction written by John T. Malito and published by . This book was released on 1982 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Integrated Gasification Combined Cycle IGCC Technologies written by Ting Wang and published by Woodhead Publishing. This book was released on 2016-11-26 with total page 929 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrated Gasification Combined Cycle (IGCC) Technologies discusses this innovative power generation technology that combines modern coal gasification technology with both gas turbine and steam turbine power generation, an important emerging technology which has the potential to significantly improve the efficiencies and emissions of coal power plants. The advantages of this technology over conventional pulverized coal power plants include fuel flexibility, greater efficiencies, and very low pollutant emissions. The book reviews the current status and future developments of key technologies involved in IGCC plants and how they can be integrated to maximize efficiency and reduce the cost of electricity generation in a carbon-constrained world. The first part of this book introduces the principles of IGCC systems and the fuel types for use in IGCC systems. The second part covers syngas production within IGCC systems. The third part looks at syngas cleaning, the separation of CO2 and hydrogen enrichment, with final sections describing the gas turbine combined cycle and presenting several case studies of existing IGCC plants. - Provides an in-depth, multi-contributor overview of integrated gasification combined cycle technologies - Reviews the current status and future developments of key technologies involved in IGCC plants - Provides several case studies of existing IGCC plants around the world
Download or read book Fundamental Issues in Control of Carbon Gasification Reactivity written by L Lahaye and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last decade there has been a renewed interest in under standing from a fundamental point of view the gasification of carbon. Basi cally there are two major issues in controlling the reactivity of carbon: i) reduction of the gasification rate of carbon materials in hostile environment ii) increase of the gasification rate in order to utilize carbonaceous compounds more effectively. Although these two objectives look somewhat contradictory, they are part of the general topics of understanding gasification reactivity of carbon. Refractory applications of carbon in furnace linings, seals and vanes, as well as the use of carbon-carbon or carbon-ceramic composites in struc tures able to withstand corrosion at high temperature require a better understanding of the fundamentals involved in carbon-oxidizing gas (02' CO , H 0) reactions. Furthermore a great interest of aluminium producers 2 2 is 10 extending the lifetime of carbon electrodes in alumina electrolysis which primarily depends on reducing their consumption rates by air or carbon dioxide. Proper control of gasification reactions is also of prime importance in manufacturing carbonaceous adsorbents like granular activated carbon clothes of high adsorption characteristics. The balance between increase of porosity and decrease in mechanical strength during activation is critical for developing new porous types of carbon materials in particular for carbon clothes and this can only be achieved by a careful control of the gasification reaction.
