DOCSLIB.ORG

A Techno-Economic, Sustainability and Experimental Assessment of the Direct Methanation of Biodiesel Waste Glycerol

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A Techno-Economic, Sustainability and Experimental Assessment of the Direct Methanation of Biodiesel Waste Glycerol i A techno-economic, sustainability and experimental assessment of the direct methanation of biodiesel waste glycerol Robert White Submitted in accordance with the requirements for the degree of Doctor of Philosophy as part of the integrated PhD with MSc in Bioenergy Doctoral Training Centre in Bioenergy, Energy Research Institute, School of Chemical and Process Engineering, The University of Leeds October 2018 The candidate confirms that the work submitted is his/her own and that appropriate credit has been given where reference has been made to the work of others. ii This copy has been supplied on the understanding that it is copyright material and that no quotation from the thesis may be published without proper acknowledgement. © 2018 The University of Leeds and Robert William White iii Acknowledgements Whilst this PhD has been submitted in my name, it takes a great deal more than one individual to complete a body of work such as this. Firstly I would like to thank my supervisors, Dr Valerie Dupont and Prof. Timothy Cockerill for their support, guidance and patience throughout the last four years. I would also like to thank the following from my research group: Oliver Grasham for listening to my ideas and always having the time to have a discussion, Robert Bloom for our chats in the laboratory and Sergio for his help calibrating the micro GC. My colleagues from the first year and second year of the bioenergy CDT are deserving of my thanks and gratitude and include, in no particular order: Diarmaid Clergy, Andrew Dyer, Gillian Finnerty, Luke Conibear, Hana Mandova, Lee Roberts, Charlotte Stead and Kiran Palmer as well as Jeni Spragg, Charlotte Weaver, Nicola Wood, Daisy Thomas, Iram Razaq, and Ric Birley. Several members of staff made this work possible and I would like to thank the energy building engineering technicians; Kevin Dyer, Scott Prichard, Gurdev Bogall as well as the lab 1.10 technicians Adrian Cunliffe and Karine Alves Thorne I would also like to thank the Engineering and Physical Science research council (ESPRC) for my studentship and Freddy from the University of Yucatan, Mexico, for his guidance with life cycle analysis and collaboration. Someone who should not go unmentioned is my long suffering partner, Emma Johnson. My gratitude for her patience, kindness and love knows no bounds and has been pivotal in the completion of this work, and retention of my sanity. Finally I would like to thank my family, my mother Ricamor, my father Duncan, and my brother Edward who have made me what I am today. iv Abstract Crude glycerol from biodiesel production is a potential feedstock for energy in many parts of the world. A concept that is yet to be explored is the conversion of glycerol to a methane rich gas known, in this case, as bio-SNG, by taking advantage of steam reforming and methanation reactions in a single reactor. This process is known as direct methanation. Direct methanation is a type of low temperature steam reforming and is performed at temperatures lower than those commonly used for hydrogen production from organic feedstock. When applied to glycerol, it is termed ‘GLT-SR’ in this thesis. GLT-SR allows glycerol to be transformed into a gaseous energy vector that can be converted to energy on- site at the biodiesel refinery to offset fossil natural gas usage, for instance, in the energy intensive bean or seed crushing stage. The present work identifies the feasibility of a GLT-SR process using a design process framework and included process modelling in Aspen Plus, technoeconomic and environmental energy life cycle impacts analysis and laboratory scale experiments using pure glycerol to avoid any unknown impacts of contaminants contained in crude glycerol. Based on the thermodynamic analysis and process model, the optimum conditions favouring methane production and energy efficiency were 8 atm, with a feed molar steam to carbon ratio of 2.56 and an inlet temperature of 474 K. When compared to natural gas, bio-SNG from soybean based glycerol had the potential to decrease global warming potential with a trade-off of increased eutrophication, terrestrial ecotoxicity and freshwater aquatic ecotoxicity potential. The economic analysis based on biodiesel plants located in the USA, determined that a gas price of USD$6-7 per million BTU was necessary to achieve acceptable rates of return and coincided with the states of Missouri and Arkansas. A gasification rig was constructed and laboratory experiments confirmed that reducing the temperature were essential to maximising methane production. At steady state roughly 90% of the glycerol was converted to carbon gases with the most effective conditions achieving 66% of the CH4 conversion at equilibrium at 673 K (400 °C), steam to carbon ratio 2.5, pressure 1 atm and weight hourly space velocity of 0.54 hr-1. Thus current process conditions showed the process was operating away from the desired equilibrium for maximum CH4. Based on economics and environmental analysis, the process is feasible but would rely on an optimised process to maximise CH4 production and further trials to determine the impact of glycerol contaminants. v Table of Contents Acknowledgements ................................................................................................................ iii Abstract ................................................................................................................................... iv Table of Contents ..................................................................................................................... v List of Tables ........................................................................................................................... xi List of Figures ........................................................................................................................ xiii Abbreviations ...................................................................................................................... xviii Nomenclature ....................................................................................................................... xxi Achievements ..................................................................................................................... xxiii i. Journal Papers ................................................................................... xxiii ii. Magazine Articles ............................................................................. xxiii iii. Conference Proceedings ................................................................. xxiii iv. Conference Oral Presentations ....................................................... xxiii v. Conference Poster Presentations .................................................... xxiii vi. Prizes ............................................................................................... xxiv 1 Introduction ................................................................................................................... 1 1.1 Research Motivation ............................................................................................. 1 1.1.1 Decarbonising Transport ................................................................................... 2 Replacing fossil diesel with biodiesel ........................................................................ 2 1.1.2 Decarbonising heat ........................................................................................... 5 1.1.2.1 Renewable and synthetic natural gas ..................................................... 7 1.1.2.2 Synthetic natural gas from fossil fuels .................................................... 8 1.1.2.3 Biomass gasification for synthetic natural gas ..................................... 11 1.1.2.4 State of biomass to synthetic natural gas technologies ....................... 12 1.1.2.5 Biodiesel glycerol as a feedstock for decarbonising heat ..................... 14 1.1.2.6 Crude vs Pure Glycerol .......................................................................... 16 1.1.2.7 Steam reforming and methanation ...................................................... 20 1.2 Research Justification .......................................................................................... 22 1.2.1 Direct methanation of glycerol for Bio-SNG ................................................... 23 vi 1.2.2 Process Integration in a Soybean Biodiesel Refinery ....................................... 24 1.3 Research Objectives ............................................................................................. 26 1.4 Research Challenges and Novelty ........................................................................ 27 1.5 Applying the design process to assess the feasibility of the direct methanation of glycerol 29 1.6 System Boundaries ............................................................................................... 30 2 Process Simulation ........................................................................................................ 32 2.1 Introduction ......................................................................................................... 32 Steady state and dynamic equilibrium ......................................................................... 33 2.2 Literature Review ................................................................................................. 35 2.3 Design Needs .......................................................................................................
Load more

Recommended publications
  • The Mond Gas-Producer Plant and Its Application.”
    190 HUNPHREP OX THE MOND GAS-PRODUCER PLANT. [Minutesof 16 March, 189;. JOHN WOLFE BARRY, C.E., F.R.S., President, in the Chair. (Paper No. 2956.) ’‘ The Mond Gas-Producer Plant and its Application.” By HERBERTALFRED HUMPHREI’, ASSOC.M. Inst. C.E. GASEOUSfuel possesses certain well-recognised advantages over solid fuel ; it is easily handled, and its combustion is completely under control, and causes no smoke or dirt. It is also applicable to many cases where solid fuel could not be used, and it is the fuel of internal-combustion engines. For these and other reasons the demand for it is rapidly increasing ; and it is the function of the gas-producers to convertsolid fuel intothe gaseous state. In a Paper read before the Institution in 1886, Mr. F. J. Rowan gave an account of the Wilson, Dowson, Grobe,Sutherland, Siemens, and other gas-producers which had been employed up to that time ; and Papers on the application of the Dowson producer to the generation of gas for motive power hare since been com- municated to the Institution by Mr. J. E. Dowson.2 The Author proposes to deal with recentadvances inthis department of industry. Producer gas was used for furnace work many years before its adoption for use in gas-engines ; and its applicationto generating power, which only commenced about 18 years ago, has through- out beenclosely connected with the name of Mr. Dowson. His success, and the great possibilities in this field of work,led to the construction of many other producersfor power gas; those of Wilson, Taylor,Thwaites and Lencauchez having achieved excellentresults.
    [Show full text]
  • Producer Gas Plants. a Profile of the Sites, the Processes Undertaken and Type of Contaminants Present
    Producer Gas Plants. A profile of the sites, the processes undertaken and type of contaminants present. Prepared by Dr Russell Thomas, Parsons Brinckerhoff, Queen Victoria House, Redland Hill, Bristol BS6 6US, UK, 0117-933-9262, [email protected]. The author is grateful to members of the IGEM, Gas History Panel for their technical assistance. Introduction William Murdock used coal gas to light his house and office in Redruth in 1792; this was the first commercial application C of gas in the world. Gas has been used ever since for commercial, industrial and domestic applications. Gas was first produced from coal and later on from oil until its replacement by natural gas in the mid 1970s. The conventional production of gas from coal is well documented; however, there was also another method of gas production D which is less well known, this was called “producer gas”. Producer gas plants started to become popular in the early 1880 and were in extensive use by 1910. As producer gas plants evolved from the first plant built by Bischof (figure 1) through to their demise in competition in the mid 20th century, many varied types evolved. Following Bischof’s early development of the gas producer the next major development was that of Fredrick Siemens who developed a combined gas producer and regenerative furnace in 1857. This system was gradually improved and introduced to the B UK through William Siemens. Producer gas plants provided a A great benefit to those industries requiring high and uniform temperatures. This greatly aided those industrial processes Fig. 1. Bischof Gas Producer.
    [Show full text]
  • Library of Congress Classification
    T TECHNOLOGY (GENERAL) T Technology (General) Periodicals and societies. By language of publication 1 English 2 French 3 German 4 Other languages (not A-Z) (5) Yearbooks see T1+ 6 Congresses Industrial museums, etc. see T179+ International exhibitions see T391+ 7 Collected works (nonserial) 8 Symbols and abbreviations Dictionaries and encyclopedias 9 General works 10 Bilingual and polyglot Communication of technical information 10.5 General works Information centers 10.6 General works Special countries United States 10.63.A1 General works 10.63.A2-Z By region or state, A-Z 10.65.A-Z Other countries, A-Z 10.68 Risk communication 10.7 Technical literature 10.8 Abstracting and indexing Language. Technical writing Cf. QA42 Mathematical language. Mathematical authorship 11 General works 11.3 Technical correspondence 11.4 Technical editing 11.5 Translating 11.8 Technical illustration Cf. Q222 Scientific illustration Cf. T351+ Mechanical drawing 11.9 Technical archives Industrial directories 11.95 General works By region or country United States 12 General works 12.3.A-Z By region or state, A-Z Subarrange each country by Table T4a 12.5.A-Z Other regions or countries, A-Z Subarrange each country by Table T4a 13 General catalogs. Miscellaneous supplies 14 Philosophy. Theory. Classification. Methodology Cf. CB478 Technology and civilization 14.5 Social aspects Class here works that discuss the impact of technology on modern society For works on the role of technology in the history and development of civilization see CB478 Cf. HM846+ Technology as a cause of social change History Including the history of inventions 14.7 Periodicals, societies, serials, etc.
    [Show full text]
  • THE RELATION BETWEEN HEATING VALUE of GAS and ITS USEFULNESS to the CONSUMER a CRITICAL REVIEW of the PUBLISHED DATA Bye
    T290 THE RELATION BETWEEN HEATING VALUE OF GAS AND ITS USEFULNESS TO THE CONSUMER A CRITICAL REVIEW OF THE PUBLISHED DATA ByE. R. Weaver ABSTRACT The introduction, Section I, contains a description of the sources and a dis- cussion of the character of the available information which has an important bearing upon the subject treated. The data are divided into two classes, (1) direct observations of the useful effects obtained from the utilization of gases of different qualities in the appliances in common use, and (2) statistical data showing changes in the quantity of gas used which accompanied changes in heating value. Section II contains a summary and some discussion of the data of the first class. Because of the large amount of such material only the briefest summary of such information consistent with clearness has been given. In some cases in which data are not available to the public in published form, and in others in which the reviewer does not agree with the authors upon the interpretation of the data, detailed figures are presented. Section III contains a summary and discussion of the general significance of the information presented in Section II. There is very general agreement that in all kinds of commercial appliances the potential heat of the gas is used with substantially equal efficiency, whatever the other properties of the gas may be. An explanation is offered for the general applicability of this relation to the results observed with appliances of the most varied character when using gases of any composition within the ordinary limits of commercial supply.
    [Show full text]
  • Guião De Relatório De Projecto / Estágio
    Integrated Masters in Chemical Engineering Packed Bed Membrane Reactor for the Water- Gas Shift Reaction: Experimental and Modeling Work Masters Thesis of Joel Alexandre Moreira da Silva Developed in the framework of the course of dissertation performed at Multiphase Reactors Group, Department of Chemical Engineering & Chemistry, Eindhoven University of Technology Supervisor at TU/e: Eng. Arash Helmi, Dr. Fausto Gallucci and Dr. Martin Van Sint Annaland Chemical Engineering Department July of 2013 Packed Bed Membrane Reactor for the Water-Gas Shift Reaction: Experimental and Modeling Work Acknowledgements I would like to deeply thank Engineer Arash Helmi for all the advice, patiente, support, encouragement and dedication to this project. His help was fundamental to this project. I would also like to thank Doctor Fausto Gallucci for all the good advices given and all the help provided during this project. I would also like to thank Doctor Martin Van Sint Annaland for all the suggestions made regarding the scope of my project and for making this project possible to happen. Also a special thanks to Masters student Rogelio González for all the help while using the phenomenological models that he was developing. Also a very special thanks to Joris for the technical support provided to the set-up I used and for all the technical advices. I would like to thank all SMR group members for making this group such a good one, with such a good environment. Finally I would like to thank my family and friends for their encouragement and support. They played undoubtedly a very important role during this dissertation project.
    [Show full text]
  • Techno-Economic Modelling of Tidal Energy Converter Arrays in the Tacoma Narrows
    Journal of Marine Science and Engineering Article Techno-Economic Modelling of Tidal Energy Converter Arrays in the Tacoma Narrows Mathew B. R. Topper 1,* , Sterling S. Olson 2 and Jesse D. Roberts 2 1 Data Only Greater, Maynooth W23 E8C6, Ireland 2 Sandia National Laboratories, Albuquerque, NM 87185, USA; [email protected] (S.S.O.); [email protected] (J.D.R.) * Correspondence: [email protected] Received: 27 July 2020; Accepted: 17 August 2020; Published: 22 August 2020 Abstract: Hydrokinetic tidal energy converter (TEC) technology is yet to become cost competitive with other renewable energy sources. Understanding the interaction between energy production and the costs incurred harvesting that energy may unlock the economic potential of this technology. Although hydrodynamic simulation of TEC arrays has matured over time, including demonstration of how small and large arrays affect the resource, integration of cost modelling is often limited. The advanced ocean energy array techno-economic modelling tool ‘DTOcean’ enables designers to calculate and improve the levelised cost of energy (LCOE) of an array through parametric simulation of the energy extraction, design of the electrical network, moorings and foundations, and simulation of the installation and lifetime operations and maintenance of the array. This work presents a verification of DTOcean’s ability to simulate the techno-economic performance of TEC arrays by reproducing the hypothetical RM1 reference model, a semi-analytical model of a TEC array based in the Tacoma Narrows of Washington state, U.S.A. It is demonstrated that DTOcean can produce a reasonable estimate to the LCOE predicted by the reference model, giving (in Euro cents per kiloWatt hour) 36.69 ¢/kWh against the reference model’s 34.612 ¢/kWh for 10 TECs, while for 50 TECs, DTOcean calculated 20.34 ¢/kWh compared to 17.34 ¢/kWh for the reference model.
    [Show full text]
  • Hydrocarbon Torch Gas Kohlenwasserstoffgas Für Schweissbrenner Gaz D’Hydrocarbures Pour Chalumeau
    Europäisches Patentamt *EP000734430B1* (19) European Patent Office Office européen des brevets (11) EP 0 734 430 B1 (12) EUROPEAN PATENT SPECIFICATION (45) Date of publication and mention (51) Int Cl.7: C10L 3/00, C10L 1/18 of the grant of the patent: 23.06.2004 Bulletin 2004/26 (86) International application number: PCT/US1994/011619 (21) Application number: 95904049.4 (87) International publication number: (22) Date of filing: 14.10.1994 WO 1996/011998 (25.04.1996 Gazette 1996/18) (54) Hydrocarbon torch gas Kohlenwasserstoffgas für Schweissbrenner Gaz d’hydrocarbures pour chalumeau (84) Designated Contracting States: (74) Representative: Crump, Julian Richard John et al AT BE CH DE DK ES FR GB GR IT LI NL PT FJ Cleveland, 40-43 Chancery Lane (43) Date of publication of application: London WC2A 1JQ (GB) 02.10.1996 Bulletin 1996/40 (56) References cited: (73) Proprietor: EXCELLENE LIMITED WO-A-94/01515 DE-A- 2 455 727 Port Vila (VU) GB-A- 569 108 US-A- 3 869 262 US-A- 5 232 464 US-A- 5 236 467 (72) Inventor: FRITZ, James, Edward Port Townsend, WA 98368 (US) • DATABASE WPI Section Ch, Week 9540 Derwent Publications Ltd., London, GB; Class H06, AN 95-311792 XP002085604 & ZA 9 408 012 A (EXCELLENE LTD) , 26 July 1995 Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement.
    [Show full text]
  • Download This PDF File
    THE SUCTION GAS PRODUCER. 117 lations as .441 of a penny, and with steam installations .418 of a penny. The whole position was summed up clearly when he s;howed that the gas engine was only working at economical conditions at full load, and that the consumption of gas was increased by nearly 40 per cent, at half load. Oonsequently a gas engine which did not run continually at full load could never show tbJe guaranteed minimum fuel consumption: whereas the steam engine suffered much less in economy through such a r eduction in load. Of COlli'se if gas producer plants replaced old-fashioned and out-of-date steam plants an economy could be shown, but it could be clearly demonstrated that, by using an up-to-date water-tube boiler, superhea ted steam and a compound engine-not necessarily condensing- and taking into consideration the advantages of sarety, reliability. and flexibility, let alone economy, the steam plant still held the day. The "Ellectrical Times," which published every week the works costs of the 300 Electric Light Stations at H ome in accordance with the returns required by Act of Parlia~nt, furnished a strLking example of the success of steam plants as against gas plants in economy. There were only four gas engine instal­ lations, and these showed a marked increase in the \vOl'king costs as compared with most of the steam plants, a nd cost three times more for maintenance than Mr. Forkels lestimate_ So that the theoretical estimate of .41 of a penny for suction gas plants per H.P_ could not be relied upon, unless undle r exceptional conditions favorable t o a gas plant, :md considering t he cost of labor and repairs in the Colonies.
    [Show full text]
  • Phosphate-Based Catalysts for the WGS Reaction: Synthesis, Reactivity and Mechanistic Considerations
    PhD Thesis Doctoral Program Science and Technology of New Materials Phosphate-based catalysts for the WGS reaction: Synthesis, reactivity and mechanistic considerations Sara Mª Navarro Jaén Supervisors Oscar Hernando Laguna Espitia José Antonio Odriozola Gordon Chapter I General Introduction Chapter I: General Introduction 1.1. History and background of the Water-Gas Shift reaction The production of water gas (Eq. 1.1), consisting in an equimolar mixture of CO and H2, was first discovered in 1780 by the Italian researcher Felice Fontana, when he quenched incandescent coke with water under a glass bell jar. The composition of the mixture was later determined by Lavoisier [1-3]. C + H2O ↔ CO + H2 Eq. 1.1 Nevertheless, the reaction was first patented in 1888 by Ludwig Mond and Carl Langer [4], whose work was focused on the ammonia synthesis from coal and coke. Mond developed the producing process of the so-called Mond gas, which is the reaction product obtained from the reaction of air and steam passed through coal/coke (CO2, CO, H2, N2, …) [2, 5], which became the basis for future coal gasification processes. Mond and Langer were also the pioneers using fuel cells, feed with coal-derived Mond gas [6]. However, feeding pure hydrogen to the fuel cell was a hard task, since large amounts of CO were present in the Mond gas, thus poisoning the Pt electrode. Therefore, Mond solved this problem by passing a mixture of the Mond gas and steam through finely divided nickel at 400 °C, producing CO2 and more H2. After CO2 elimination by alkaline wash, the H2-rich stream could be feed to the fuel cell [2, 5, 7].
    [Show full text]
  • Water Gas Plants
    Gasworks Profile C: Water Gas Plants Gasworks Profiles Gasworks Profile A: The History and Operation of Gasworks (Manufactured Gas Plants) Contents in Britain Gasworks Profile B: Gasholders and their Tanks Gasworks Profile C: Water Gas Plants 1. Introduction................................................................................... C1 Gasworks Profile D: Producer Gas Plants 2. The Early Development of Water Gas..........................................C1 3. Different Systems Used for the Manufacture of Water Gas......... C3 ISBN 978-1-905046-26-3 © CL:AIRE 2014 4. The Development of Intermittent Water Gas Plants..................... C3 5. The ‘Run’ and ‘Blow’..................................................................... C5 Published by Contaminated Land: Applications in Real Environments (CL:AIRE), 6. Types of Intermittent Water Gas Plant......................................... C7 32 Bloomsbury Street, London WC1B 3QJ. 7. Blue-Water Gas Plants................................................................. C8 8. The Operation of an Intermittent Carburetted Water-Gas Plant... C9 All rights reserved. No part of this publication may be reproduced, stored in a retrieval 9. Types of Fuel used....................................................................... C16 system, or transmitted in any form or by any other means, electronic, mechanical, photocopying, recording or otherwise, without the written permission of the copyright 10. Oil Feedstocks used to enrich Water Gas.................................... C17 holder. All
    [Show full text]
  • Fuel Is Defined As a Substance Composed Mainly of Carbon and Hydrogen Because These Elements Will Combine with Oxygen Under Suit
    6 FUELS 6.1 Introduction <s Fuel is defined as a substance composed mainly of carbon and hydrogen because these elements will combine with oxygen under suitable conditions and give out appreciable quantities of heat. Fuels are used in industry for production of heat and in turn this heat produced is converted into mechanical work. Before the invention of nuclear energy and nuclear fuels, chemical energy of fuels, which may be in solid, liquid or gaseous forms was only the natural source of energy mainly. Coal, crude oil and natural gas are fossil fuels. Even today, major portion of . energy demand is met by fossil fuels. At present, the major share of energy demand is met by crude oil which supplies nearly 42% of the total energy demand. Coal supplies nearly 32% and natural gas about 21% of the energy demand. Remaining 5% of energy demand is supplied by nuclear power and hydraulic power. All human, industrial, and agricultural wastes constitute potential significant source of energy. Normally a large portion of such waste is combustible matter e.g. wood, paper, tar, textile, plastic, plant, leaves etc. Bio-gas is obtained by fermentation in the sewage disposal system, or by the fermentation of cattle waste, farm waste, etc. If the fermentation is carried out in the absense of air, the gas produced may have the concentration of methane as high as 75%. The remaining part is mostly carbon dioxide and hydrogen. With the increasing gap between the demand and supply of crude oil, and with the fast reducing fossil fuel reserves, it has new become essential to find out alternatives to gasoline for nutomobiles, heavy vehicles, and aircrafts.
    [Show full text]
  • Gas Producers for Internal Combustion Engines: Ancient and Modern
    The Piston Engine Revolution Gas Producers for Internal Combustion Engines: Ancient and Modern D. Andrews and F. Starr Gas producers have been used as a source of energy for large stationary gas engines from the earliest days of the IC piston engine. The paper reviews the history of the gas producer, but also comments on automotive vehicles fitted with gasifiers. Some examples of running costs for stationary engines are given. The paper describes a recent wood based gasifier project that fuelled a modified 250 kW natural gas engine. The problems encountered give an insight into the operation of gas producers of the past. KEYWORDS: gasification, producers, fuels, automotive, modern types. Gasification Processes The terms pyrolysis and gasification are used here in the following way: Pyrolysis is the heating of coal or wood in the absence of air, thereby driving off volatile combustible gases, leaving coke as a residue, as in the original town gas process (or charcoal if wood is employed). The gaseous products contain methane, hydrogen, carbon monoxide with some carbon dioxide and nitrogen. In addition the gaseous pyrolysis products contain tars, liquid hydrocarbons, phenols and ammonia liquors, which condense out at ambient temperatures. Pyrolysis occurs between about 400-1000°C1 Gasification is today referred to as the partial combustion of coal, coke or wood, in which as much as possible of the fuel is turned into a gas. The main “gasification” reactions, which occur between about 700-1400°C are: C+O2 = CO2 (1) CO2+C = 2CO (2) H2O + C = CO + H2 (3) It will be apparent that the volume of gas produced by pyrolysis, as in town gas manufacture, where much of the coal remains as coke, is significantly less than that produced from the same tonnage of coal in a gas producer.
    [Show full text]