DEUTSCHE FORSCHUNGS- UNO VERSUCHSANSTALT FOR LUFT- UNO RAUMFAHRT E.V. (DFVLR) SOLAR THERMAL ENERGY UTILIZATION German Studies on Technology and Application Editor: M. Becker Volume3: SolarThermal Energy for Chemical Processes EXIRA MATERIALS extras.springer.com Springer-Verlag Berlin Heidelberg GmbH 1987 Dr.-lng. Manfred Becker Hauptabteilung Energietechnik der Deutschen Forschungs-und Versuchsanstalt fi..ir Luft-und Raumfahrt e. V. (DFVLR), Kbln Additional material to this book can be downloaded from http://extras.springer.com ISBN 978-3-540-18032-6 ISBN 978-3-662-09933-9 (eBook) DOI 10.1007/978-3-662-09933-9 This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broad casting, reproduction on microfilms or in other ways, and storage in data banks. Duplication of this publication or parts thereof is only permitted under the provisions of the German Copyright Law of September 9, 1965, in its version of June 24, 1985, and a copyright fee must always be paid. Viola tions fall under the prosecution act of the German Copyright Law. © Springer-Verlag Berlin Heidelberg 1987 Originally published by Springer-Verlag Berlin Heidelberg New York in 1987 The use of registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regula tions and therefore free for general use. 2362/3020-543210 Preface The energy crisis in 1973 and 1979 initiated a great number of activities and programs for low and high temperature applica tion of solar energy. Synthetic fuels and chemicals produced by solar energy is one of them, where temperatures in the range of 600-1000°C or even higher are needed. In principle such high temperatures can be produced in solar towers. For electricity production, the feasibility and operation of solar tower plants has been examined during the SSPS - project (Small Solar Power System) in Almeria, Spain. The objective of Solar Thermal Energy Utilization is to extend the experience from the former SSPS - program in to the field of solar produced synthetic fuels. New materials and technolo gies have to be developed in order to research this goal. Metallic components now in use for solar receivers need to be improved with respect to transient operation or possibly replaced by ceramics. High temperature processes, like steam-methane reforming, coal conversion and hydrogen produc tion need to be developed or at least adapted for the unconven tional solar operation. Therefore Solar Thermal Energy Utiliza tion is a long term program, which needs time for its develop ment much more time than the intervals expected in between further energy crisis. The "Studies on Technology and Applica tion on Solar Energy Utilization" is a necessary step in the right direction in order to prepare for the energy problems in the future. Prof. Dr. H. F. Knoche Rheinisch-Westfalische Technische Hochschule Aachen, Federal Republic of Germany v SOLAR THERMAL ENERGY UTILIZATION German Studies on Technology and Application Volume 3: Solar Thermal Energy for Chemical Processes Contents Page Steam Reforming of Methane Utilizing Solar Heat 1 W.O. Muller, Lurgi, Frankfurt Solar Steam Reforming of Methane (SSRM) 179 Program Proposals A. Kalt, DFVLR, Koln Solar Steam Reforming of Methane - Program Proposals - 195 U. Leuchs, Interatom, Bergisch-Gladbach Comparative Investigations and Ratings of Different 251 Solar Systems Using Tubular Steam Reformers w. D. Muller, Lurgi, Frankfurt and H. Fuhrmann, MAN-Technologie GmbH, Munchen Process Synthesis of a Gasification Process 547 Modified for High Solar Energy Integration G. Birke, R. Reimert, Lurgi, Frankfurt Utilization of Solar Energy for Hydrogen Production 621 by High Temperature Electrolysis of Steam E. Erdle, J. Gro~, V. Meyringer, Dornier, Friedrichshafen. Index of Authors 763 VI Volume 1: General Investigations on Energy Availability Yearly Yield of Solar CRS-Process Heat and Temperature of Reaction, P. Koepke, H. Quenzel, R. Sizmann, Universitat-Munchen Literature Survey in the Field of Primary and Secondary Concentrating Solar Energy Systems Concerning the Choice and Manufacturing Process of Suitable Materials, A. Grychta, J. Kaufmann, P. Lippert, G. Lensch, NU-Tech, Neumunster Considerations and Proposals for Future Research and Development of High Temperature Solar Processes, F. Boese, P.E. Huber, H.W. Kappler, J. Lammers, Motor Columbus, Stuttgart Volume 2:. Technologies of Heat Exchangers (Receiver/Reformer) and Storage Volumetric Ceramic Receiver Cooled by Open Air Flow - Feasibility Study -, K. Freudenstein, B. Karnowsky Interatom, Bergisch-Gladbach A Multistage Steam Reformer Utilizing Solar Heat, W. Jager, U. Leuchs, W. Siebert, Interatom, Bergisch-Gladbach Layout of High Temperature Solid Heat Storages, H. Kalfa, Chr. Streuber, Didier, Wiesbaden Expert Opinion and Co-operation in the Development Program High Temperature Storage Tank, Th.J. Bohn, K. Werner, W. Bitterlich, F.J. Josfeld, Uni-Essen GHS VII PART I (LURGI) STEAM REFORMING OF METHANE UTILIZING SOLAR HEAT W,D, MULLER LURGI, FRANKFURT Contents Steam Reforming of Methan Utilizing Solar Heat (Part I) Purpose of Study and First Conclusions 4 2 Investigation of Overall Systems 7 3 Concepts of Solar Energy Coupling 10 4 Description of Various Reforming Systems 13 Including Tables I to IV 5 Conceptual Design of Reactors 30 6 Receiver Designs and Heat Carrier Systems 33 (MAN-Report) 7 Testing of a Concept at Almeria, Spain 63 8 Conclusions 64 - 3 - 1. PURPOSE OF STUDY AND FIRST CONCLUSIONS There is a worldwide interest to use solar energy to save or substitute fossil material, which is taken as fuel or chemical feedstock in present technologies. Among the possibilities, which are studied in detail for such substitution of fossil energy by solar energy, the reforming of methane with water vapour may have a good chance for application as this process pre dominantly is used for the production of several basic materials in chemistry, as ammonia, methanol and hydro gen. This process needs as endothermic reaction a high portion of energy for firing, which may be substituted by solar energy. Among the possibilities to introduce such solar radiation to the pDocess there are two basic modes: an integrated and a separated solution. In the integrated solution catalyst containing re forming tubes are direct·ly radiated by the (reflected) solar energy. Solar receiver and chemical reformer form an integrated unit. In the separated solution the (reflected) solar energy is heating up in tne solar receiver any heat carrying medium, which is recycled, and which on its part is heating the chemical reactor, which may be arranged separate from the receiver. It was the purpose of this study to generate data that would allow a preselection of a system, i.e. integrated or separated solution, which is being thought to be superior to the other and which should be further - 4 -