Water for Energy and Fuel Production GREEN CHEMISTRY AND CHEMICAL ENGINEERING Series Editor: Sunggyu Lee Ohio University, Athens, Ohio, USA Proton Exchange Membrane Fuel Cells: Contamination and Mitigation Strategies Hui Li, Shanna Knights, Zheng Shi, John W. Van Zee, and Jiujun Zhang Proton Exchange Membrane Fuel Cells: Materials Properties and Performance David P. Wilkinson, Jiujun Zhang, Rob Hui, Jeffrey Fergus, and Xianguo Li Solid Oxide Fuel Cells: Materials Properties and Performance Jeffrey Fergus, Rob Hui, Xianguo Li, David P. Wilkinson, and Jiujun Zhang Efficiency and Sustainability in the Energy and Chemical Industries: Scientific Principles and Case Studies, Second Edition Krishnan Sankaranarayanan, Jakob de Swaan Arons, and Hedzer van der Kooi Nuclear Hydrogen Production Handbook Xing L. Yan and Ryutaro Hino Magneto Luminous Chemical Vapor Deposition Hirotsugu Yasuda Carbon-Neutral Fuels and Energy Carriers Nazim Z. Muradov and T. Nejat Veziro ˇ glu Oxide Semiconductors for Solar Energy Conversion: Titanium Dioxide Janusz Nowotny Lithium-Ion Batteries: Advanced Materials and Technologies Xianxia Yuan, Hansan Liu, and Jiujun Zhang Process Integration for Resource Conservation Dominic C. Y. Foo Chemicals from Biomass: Integrating Bioprocesses into Chemical Production Complexes for Sustainable Development Debalina Sengupta and Ralph W. Pike Hydrogen Safety Fotis Rigas and Paul Amyotte Biofuels and Bioenergy: Processes and Technologies Sunggyu Lee and Y. T. Shah Hydrogen Energy and Vehicle Systems Scott E. Grasman Integrated Biorefineries: Design, Analysis, and Optimization Paul R. Stuart and Mahmoud M. El-Halwagi Water for Energy and Fuel Production Yatish T. Shah Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business Water for Energy and Fuel Production Yatish T. Shah Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business Water for Energy and Fuel Production Yatish T. Shah CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2014 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed on acid-free paper Version Date: 20140319 International Standard Book Number-13: 978-1-4822-1618-9 (Hardback) This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, includ- ing photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging‑in‑Publication Data Shah, Yatish T. Water for energy and fuel production / author, Yatish T. Shah. pages cm. -- (Green chemistry and chemical engineering) Summary: “Water in all its forms may be the most important solvent in the development of the new “Energy Economy”. This book illustrates that as energy and fuel industries diversify, we are transitioning to an economy where water will play a more and more important role in the supply of energy and fuels. It discusses the role of water in the production of raw fuels such as oil, gas, coal, uranium, and biomass. It also describes methods for how supercritical water and steam are vital for the conversion of raw fuels to synthetic fuels. “-- Provided by publisher. Includes bibliographical references and index. ISBN 978-1-4822-1618-9 (hardback) 1. Water--Industrial applications. 2. Energy industries--Materials. 3. Hydraulic machinery. 4. Water as fuel. 5. Green chemistry. I. Title. TJ840.S435 2014 621.042--dc23 2014002521 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2014 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed on acid-free paper Version Date: 20140319 International Standard Book Number-13: 978-1-4822-1618-9 (Hardback) This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, includ- ing photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging‑in‑Publication Data Shah, Yatish T. Water for energy and fuel production / author, Yatish T. Shah. pages cm. -- (Green chemistry and chemical engineering) Summary: “Water in all its forms may be the most important solvent in the development of the new “Energy Economy”. This book illustrates that as energy and fuel industries diversify, we are transitioning to an economy where water will play a more and more important role in the supply of energy and fuels. It discusses the role of water in the production of raw fuels such as oil, gas, coal, uranium, and biomass. It also describes methods for how supercritical water and steam are vital for the conversion of raw fuels to synthetic fuels. “-- Provided by publisher. Includes bibliographical references and index. ISBN 978-1-4822-1618-9 (hardback) 1. Water--Industrial applications. 2. Energy industries--Materials. 3. Hydraulic machinery. 4. Water as fuel. 5. Green chemistry. I. Title. TJ840.S435 2014 621.042--dc23 2014002521 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com The Open Access version of this book, available at www.taylorfrancis.com, has been made available under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 license. v Contents Series Preface ........................................................................................................... xv Preface....................................................................................................................xvii Author .....................................................................................................................xxi Chapter 1 Introduction ..........................................................................................1 1.1 Global Energy Landscape: Past, Present, and Future ...............1 1.2 The Theme and Outline of the Book .........................................5 1.2.1 Chapter 2: Water for Raw Fuel Production ..................6 1.2.2 Chapter 3: Water as Energy Carrier .............................7 1.2.3 Chapter 4: Steam for Synthetic Gas Production...........8 1.2.4 Chapter 5: Synthetic Fuel Production by Water under Subcritical Conditions ........................................9 1.2.5 Chapter 6: Production of Synthetic Fuels by Aqueous-Phase Reforming ......................................... 11 1.2.6 Chapter 7: Production of Synthetic Fuels and Chemicals by Hydrolysis Followed by Selective Catalytic Conversions................................................. 11 1.2.7 Chapter 8: Production of Hydrogen and Methane by Anaerobic Digestion of Aqueous Waste ................ 12 1.2.8 Chapter 9: Production of Ethanol by Aqueous- Phase Fermentation..................................... 12 1.2.9 Chapter 10: Production of Synthetic Fuels by Supercritical Water ..................................................... 13 1.2.10 Chapter 11: Production of Hydrogen by Water Dissociation ................................................................ 13 1.2.11 Chapter 12: Production of Methane from Gas Hydrates...................................................................... 14 1.2.12 Chapter 13: Water as a Direct Source of Energy ....... 14 1.3 Water-Based Refinery and Water Management for the Future .... 15 References .......................................................................................... 16 Chapter 2 Role of Water in Recovery and Production of Raw Fuels .................. 17 2.1 Introduction ............................................................................. 17 2.2 Increased Water Usage for Recovery of Coal Bed Methane and Gas from Geopressurized Zones ....................... 19 2.3 Enhanced Oil Recovery (EOR) Process .................................. 22 2.3.1 Chemical Processes .................................................... 23 2.3.1.1 Surfactant–Polymer Solution (Microemulsion Flooding).......................... 23 2.3.1.2 Polymer Solution.........................................24 vi Contents 2.3.1.3 Caustic Alkaline Solution ...........................24 2.3.2 Thermal Processes .....................................................24 2.3.2.1 Steam Stimulation.......................................24 2.3.2.2 Hot Water Injection.....................................25 2.3.2.3 In Situ Combustion .....................................25 2.4 Role of Water in the Fracking Process ....................................25 2.5 Water Requirement for Mining, Preparation, and Extraction of Solid Fuels ......................................................... 27 2.5.1 Oil Shale Industry ...................................................... 27 2.5.2 Tar Sand and Heavy Oil Industries ............................ 27 2.5.3 Uranium Mining and Leaching ..................................28 2.5.4 Coal Mining and Preparation ..................................... 29 References .......................................................................................... 29 Chapter 3 Energy Recovery by Benign Hydrothermal Processes ...................... 33 3.1 Introduction ............................................................................. 33 3.2 Role of Water in Production of Nuclear Power ....................... 33 3.2.1 Light Water Reactor ................................................... 33 3.2.2 Boiling Water Reactor ................................................34 3.2.3 Pressurized Water Reactor ......................................... 35 3.2.4 Pressurized Heavy Water Reactor (CANDU) ............ 36 3.2.5 Graphite-Moderated, Direct Cycle (Boiling Water) Pressure Tube Reactor ...................... 37 3.2.6 Supercritical Water-Cooled Reactor........................... 37 3.3 Hydrothermal Processes for Recovery of Geothermal Energy...................................................................................... 37 3.3.1 Enhanced Geothermal Systems ................................. 41 3.3.2 Coproduction of Geothermal Electricity in Oil and Gas Wells ............................................................. 42 3.4 Role of Water in Storage of Solar Energy ............................... 43 3.5 Steam Turbine..........................................................................44 References .......................................................................................... 45 Chapter 4 Steam Gasification and Reforming Technologies .............................. 47 4.1 Introduction ............................................................................. 47 4.2 Mechanisms, Kinetics, and Catalysis of Steam Gasification and Reforming..................................................... 50 4.2.1 Mechanism of Steam Gasification ............................. 50 4.2.2 Mechanism of Steam Reforming ............................... 52 4.2.3 Catalysts for Steam Gasification ................................ 53 4.2.3.1 Dolomite, Olivine, and Alkali Metal-Based Catalysts ................................ 54 4.2.3.2 Nickel-Based Catalysts ............................... 55 vii Contents 4.2.4 Catalysts for Steam Reforming .................................. 55 4.3 Dry Reforming ........................................................................ 56 4.4 Tri-Reforming .......................................................................... 59 4.5 Effects of Feedstock and Operating Conditions on Product Distributions ...............................................................60 4.5.1 Steam Gasification......................................................60 4.5.1.1 Coal .............................................................60 4.5.1.2 Biomass ....................................................... 62 4.5.1.3 Mixed Feedstock......................................... 67 4.5.1.4 Tar ............................................................... 68 4.5.1.5 Black Liquor ............................................... 69 4.5.1.6 Lignin.......................................................... 70 4.5.2 Steam Reforming ....................................................... 70 4.5.2.1 Ethanol ........................................................ 70 4.5.2.2 Methanol ..................................................... 72 4.5.2.3 Liquid Hydrocarbons .................................. 75 4.5.2.4 Glycerol....................................................... 76 4.5.2.5 Biomass ....................................................... 77 4.5.2.6 Mixed Feedstock......................................... 78 4.5.2.7 Carbon and Carbon Monoxide ................... 79 4.5.2.8 Bio-Oil ........................................................80 4.6 Steam Gasification and Reforming Reactors........................... 81 4.6.1 Steam Gasification Reactors....................................... 81 4.6.1.1 Fixed-Bed Gasifiers .................................... 81 4.6.1.2 Suspended Bed Reactor .............................. 82 4.6.1.3 Plasma and Free Radical Gasifiers .............84 4.6.1.4 Molten Salt Steam Gasification Reactors ...84 4.6.2 Steam Reforming Reactors ........................................ 87 4.7 Novel Steam Gasification and Reforming Processes .............. 89 4.7.1 Solar Gasification Technology ................................... 89 4.7.2 Solar Gasification Reactors and Processes.................90 4.7.3 Solar Reforming .........................................................92 4.7.3.1 ASTERIx: Solar Steam Reforming of Methane ..................................................92 4.7.3.2 The Weizmann Institute Tubular Reformer/Receiver ...................................... 93 4.7.3.3 Soltox Process ............................................. 93 4.7.3.4 Open-Loop Solar Syngas Production .........94 4.7.3.5 Other Solar Reforming Processes...............94 4.7.4 Microwave-Assisted Reforming ................................. 95 4.7.5 Underground Coal Gasification .................................. 95 4.7.5.1 Underground Gasification Reactors ............96 4.7.6 Other Novel Processes................................................ 98 References ..........................................................................................99 viii Contents Chapter 5 Hydrothermal Processes in Subcritical Water ................................. 113 5.1 Introduction ........................................................................... 113 5.1.1 Properties of Water at High Temperature and Pressure .................................................................... 114 5.2 Hydrothermal Carbonization (Wet Pyrolysis) ....................... 117 5.2.1 Reaction Mechanisms .............................................. 119 5.2.2 Effects of Operating Conditions............................... 121 5.2.3 Comparison of HTC and Dry Pyrolysis Process ..... 122 5.2.4 Product Characteristics and Usages ......................... 123 5.2.5 Process Considerations............................................. 125 5.3 Hydrothermal Liquefaction ................................................... 125 5.3.1 Reaction Mechanisms .............................................. 126 5.3.2 Effects of Operating Conditions on HTL Process ... 128 5.3.2.1 Pressure, Temperature, and Residence Time .......................................................... 128 5.3.2.2 Biomass Particle Size, Heating Rate, and Concentration ..................................... 130 5.3.2.3 Gas and Liquid Properties ........................ 131 5.3.3 Role of Feedstock ..................................................... 132 5.3.3.1 Biowastes .................................................. 132 5.3.3.2 Lignocellulose........................................... 133 5.3.3.3 Algae ......................................................... 134 5.3.4 HTU Process ............................................................ 136 5.4 Hydrothermal Gasification .................................................... 136 5.4.1 Catalysts for HTG .................................................... 137 5.5 Coal–Water Chemistry .......................................................... 139 5.5.1 Effect of Water Pretreatment of Coal on Coal Liquefaction .............................................................. 139 5.5.2 Coal Liquefaction in High-Pressure and High-Temperature Water.......................................... 141 5.5.3 Coal–Water Mixture as Fuel .................................... 142 5.5.3.1 Production of CWF................................... 144 5.5.3.2 Fuel Preparation and Transportation ........ 146 5.5.3.3 Combustion of CWF ................................. 147 References ........................................................................................ 148 Chapter 6 Aqueous-Phase Reforming and BioForming Process ...................... 157 6.1 Introduction ........................................................................... 157 6.2 Aqueous-Phase Reforming .................................................... 158 6.3 APR versus Steam Reforming ............................................... 159 6.4 Thermodynamics of APR ...................................................... 160 ix Contents 6.5 Kinetics and Catalysis of APR Process ................................. 163 6.5.1 Effects of Temperature, Carbon Number, and Pressure ............................................................. 163 6.5.2 Effects of Catalysts and Supports ............................ 163 6.5.3 Effects of Promoters and Acidity of Liquid and Solids ................................................................. 165 6.5.4 Effects of Feedstock ................................................. 166 6.5.4.1 APR of Ethylene Glycol, Alcohols, and Glycerol (Primary Feedstock with High Vapor Pressure) ................................ 166 6.5.4.2 APR of Sugar and Glucose (Primary Feedstock with Low Vapor Pressure) ....... 167 6.5.4.3 APR of Biomass and Cellulose (Secondary Feedstock).............................. 168 6.5.5 Novel Reactor Designs ............................................. 170 6.5.6 Summary .................................................................. 171 6.6 Production of Syngas and Monofunctional Groups and Their Upgrading ............................................................. 172 6.6.1 Syngas ...................................................................... 172 6.6.2 Monofunctional Groups ........................................... 172 6.7 Virent’s Bioforming Process ................................................. 173 References ........................................................................................ 178 Chapter 7 Biofine Hydrolysis Process and Derivative Product Upgrading Technologies ..................................................................................... 183 7.1 Introduction ........................................................................... 183 7.2 The Hydrolysis Process ......................................................... 185 7.3 Upgrading of Intermediate Products from the Biofine Process ................................................................................... 191 7.3.1 Transformation of Levulinic Acid............................ 192 7.3.2 Gamma-Valerolectone .............................................. 195 7.3.3 Furfuryl and Hydroxymethyl Furfuryl ..................... 196 7.3.4 Formic Acid.............................................................. 197 7.3.5 Biofine Char ............................................................. 197 7.4 Comparison of Biofine Process with Other Technologies ..... 197 7.4.1 DIBANET Project .................................................... 197 7.4.2 Biofine Process versus Fermentation Process .......... 199 7.4.3 Biofine Process versus Bioforming Process ............. 199 7.5 Large-Scale Biofine Process..................................................200 References ........................................................................................200 x Contents Chapter 8 Anaerobic Digestion of Aqueous Waste for Methane and Hydrogen ..........................................................................................205 8.1 Introduction ...........................................................................205 8.2 Basic Principles of Anaerobic Digestion ...............................206 8.3 Microbes and the Effects of Operating Conditions ...............209 8.3.1 Effects of Temperature and Ammonia Inhibition ....209 8.3.2 pH Effect ..................................................................209 8.3.3 Nutrients Effect ........................................................ 210 8.4 Feedstock Effects .................................................................. 210 8.4.1 Coir Pith ................................................................... 212 8.4.2 Whey ........................................................................ 212 8.4.3 Distillery Spent Wash ............................................... 212 8.4.4 Swine Waste ............................................................. 214 8.4.5 Byproducts of Biodiesel Production ......................... 214 8.4.6 Palm Oil Mill Effluent ............................................. 215 8.4.7 LCFAs in Wastewater............................................... 215 8.4.8 Food and Kitchen Organic Waste ............................ 216 8.4.9 Wastewater Treatment .............................................. 217 8.4.10 Dairy Effluent ........................................................... 217 8.4.11 Tofu Wastewater ....................................................... 217 8.4.12 Fruit Waste ............................................................... 218 8.5 Co-Digestion .......................................................................... 218 8.6 Effects of Harvesting, Storage, and Pretreatment ................. 219 8.6.1 Effect of Harvesting ................................................. 219 8.6.2 Storage ...................................................................... 219 8.6.3 Pretreatment ............................................................. 220 8.7 Types of Fermentation and Associated Digester Configurations ....................................................................... 220 8.7.1 Wet Fermentation ..................................................... 220 8.7.2 Dry Fermentation ..................................................... 221 8.7.3 Batch Fermentation .................................................. 221 8.7.4 Two-Stage Fermentation .......................................... 221 8.7.5 Novel Digester Technology ...................................... 222 8.8 Simulation, Modeling, Scale-Up, and Control of Fermentation Process ........................................................ 222 8.9 Purification of Biogas ............................................................ 223 8.10 Utilization of Biogas and Digestate .......................................224 References ........................................................................................ 225 Chapter 9 Hydrolysis and Fermentation Technologies for Alcohols ................ 233 9.1 Introduction ........................................................................... 233 9.2 Grain (Corn) Ethanol ............................................................. 235 9.2.1 Starch Hydrolysis ..................................................... 236 9.2.2 Yeast Fermentation ................................................... 236 xi Contents 9.2.3 Ethanol Purification and Product Separation ........... 236 9.2.4 Byproducts and Coproducts ..................................... 237 9.2.5 Environmental Implications ..................................... 237 9.3 Corn to Ethanol Process Technologies .................................. 237 9.3.1 Wet Milling Technology for Conversion of Corn to Ethanol ........................................................ 237 9.3.2 Dry Milling Corn-to-Ethanol Process ..................... 239 9.4 Cellulosic Ethanol.................................................................. 241 9.4.1 Pretreatment .............................................................244 9.4.1.1 Rapid Steam Hydrolysis............................ 245 9.4.1.2 Dilute Acid Prehydrolysis ......................... 245 9.4.1.3 Organosolv Pretreatment .......................... 245 9.4.1.4 Combined RASH and Organosolv Pretreatment ..............................................246 9.4.1.5 Ionic Liquid Pretreatment ......................... 247 9.4.2 Hydrolysis ................................................................. 247 9.4.2.1 Acid or Chemical Hydrolysis .................... 247 9.4.2.2 Enzymatic Hydrolysis ...............................248 9.4.2.3 Mechanism of Cellulose Hydrolysis ......... 250 9.4.3 Fermentation............................................................. 251 9.4.3.1 Separate Hydrolysis and Fermentation ..... 251 9.4.3.2 Simultaneous Saccharification and Fermentation ............................................. 252 9.4.3.3 Comparison between SSF and SHF Processes................................................... 253 9.4.3.4 xylose Fermentation ................................. 253 9.4.4 Ethanol Extraction during Fermentation.................. 254 9.4.5 Lignin Conversion .................................................... 255 9.4.6 Coproducts of Cellulosic Ethanol Technology ......... 255 9.4.7 Future Directions for Cellulosic Ethanol ................. 256 9.5 Fermentation of Sugar to Isobutanol ..................................... 256 References ........................................................................................ 257 Chapter 10 Fuel Production by Supercritical Water ........................................... 261 10.1 Introduction ........................................................................... 261 10.2 Properties of SCW ................................................................. 262 10.3 Role of SCW in Chemical Synthesis ..................................... 265 10.4 Oxidation in SCW .................................................................266 10.4.1 Catalysts for SCWO ................................................. 268 10.5 Decomposition and Extraction of Materials by SCW ........... 268 10.6 Gasification in SCW .............................................................. 272 10.7 Reforming in SCW ................................................................ 277 10.7.1 Liquid Fuels .............................................................. 277 10.7.2 Biomass .................................................................... 279 xii Contents 10.7.3 Glycerol .................................................................. 279 10.7.4 Ethylene Glycol ......................................................280 10.7.5 Methanol.................................................................280 10.7.6 Ethanol ................................................................... 281 10.8 Tri-Reforming in SCW ....................................................... 283 References ........................................................................................ 285 Chapter 11 Water Dissociation Technologies for Hydrogen ............................... 295 11.1 Introduction ......................................................................... 295 11.2 Electrolysis and Its Derivative Technologies ...................... 297 11.2.1 Alkaline Electrolysis .............................................. 298 11.2.2 HTE Process........................................................... 298 11.2.3 HPE Process ........................................................... 299 11.2.4 Photoelectrolysis.....................................................300 11.2.5 Photo-Aided Electrolysis ........................................300 11.2.6 Photovoltaic Electrolysis ........................................ 301 11.2.7 Solar Electrolysis .................................................... 301 11.3 Photochemical and Its Derivative Technologies ................. 301 11.3.1 Water Splitting on Semiconductor Catalysts (Photocatalysis) ......................................................302 11.3.1.1 Titanium Oxide Photocatalysts .............302 11.3.1.2 Tantalates and Niobates ........................ 303 11.3.1.3 Transition-Metal Oxides, Nitrides, and Oxynitrides ..................................... 303 11.3.1.4 Metal Sulfides .......................................304 11.3.2 Photobiological Production of Hydrogen from Water ......................................................................304 11.3.3 Plasma-Induced Photolysis ..................................... 305 11.4 Thermal and Thermochemical Decomposition of Water ... 305 11.4.1 Thermochemical Decomposition of Water ............307 11.4.1.1 The UT-3 Cycle .....................................308 11.4.1.2 Zn/ZnO Cycle ....................................... 310 11.4.1.3 SnO/SnO 2 Cycle .................................... 311 11.4.1.4 Mixed Iron Oxide Cycle ....................... 311 11.4.1.5 Carbothermal Reduction of Metal Oxides ....................................... 312 11.4.1.6 Sulfur Family Thermochemical Water Splitting Cycles ........................... 312 11.4.1.7 S-I Cycle ................................................ 314 11.4.1.8 The Westinghouse Process.................... 315 11.4.1.9 Copper–Chlorine Cycle ........................ 315 11.4.1.10 Copper–Sulfate Cycle ........................... 316 11.5 Other Miscellaneous Technologies ..................................... 319 11.5.1 Chemical Methods ................................................. 319 11.5.2 Magmalysis ............................................................ 320 xiii Contents 11.5.3 Radiolysis ................................................................. 320 11.5.4 Shock Waves and Mechanical Pulses....................... 320 11.5.5 Catalytic Decomposition of Water ........................... 321 11.5.6 Plasmolysis ............................................................... 321 11.5.7 Magnetolysis............................................................. 321 References ........................................................................................ 322 Chapter 12 Methane from Gas Hydrates ............................................................ 329 12.1 Introduction: What Is Gas Hydrate and How Is It Formed? ..... 329 12.2 Sources, Sizes, and Importance of Gas Hydrate Deposits .... 330 12.3 Importance of Gas Hydrates on Offshore Oil and Gas Operations ............................................................................. 335 12.3.1 Drilling ..................................................................... 335 12.3.2 Production by Enhanced Oil and Gas Recovery Methods .................................................................... 336 12.3.3 Natural Gas Hydrates versus Liquefied Natural Gas in Transportation .............................................. 337 12.4 Environmental Impacts of Gas Hydrates ............................. 337 12.5 Production of Methane from Gas Hydrate Reservoirs .......... 339 12.5.1 Thermal Stimulation ................................................340 12.5.2 Depressurization.......................................................340 12.5.3 Inhibitor Injection..................................................... 341 12.5.4 Gas Exchange ........................................................... 342 12.5.5 EGHR Method ......................................................... 343 12.5.6 Computer Simulation ............................................... 345 12.5.7 Commercial Applications.........................................346 References ........................................................................................346 Chapter 13 Power and Energy Directly from Water ........................................... 361 13.1 Introduction ........................................................................... 361 13.2 Hydroelectric Power by Water Dams .................................... 361 13.2.1 Conventional Dams .................................................. 363 13.2.2 Pumped Storage ....................................................... 363 13.2.3 Other Methods..........................................................364 13.2.4 Advantages and Disadvantages of Hydroelectric Power ........................................................................364 13.2.4.1 Advantages................................................364 13.2.4.2 Disadvantages ........................................... 365 13.2.5 Environmental Issues ............................................... 365 13.2.6 Size and Capacities of Hydroelectric Power Facilities ................................................................... 366 13.2.6.1 Small Hydropower Plants ......................... 366 13.2.6.2 Microhydropower Plants ........................... 366 13.2.6.3 Picohydropower Plants ............................. 367 xiv Contents 13.3 Hydrokinetic Energy and Power Generation ......................... 367 13.3.1 Why Hydrokinetic Energy? ...................................... 367 13.3.2 Hydrokinetic versus Hydroelectric Energy: Potentials and Issues................................................. 369 13.3.3 Hydrokinetic Power Devices .................................... 371 13.3.3.1 Wave Energy Converters .......................... 372 13.3.3.2 Commercial Applications of WEC ........... 372 13.3.3.3 Rotating Hydrokinetic Devices................. 376 13.3.3.4 Devices to Harness Tidal Power ............... 379 13.3.3.5 Hydrokinetic Power Barges ...................... 380 13.3.3.6 Criteria for Choice of a Device and Its Location .................................................... 381 13.3.4 Recent Commercialization Examples in the United States ............................................................ 382 13.4 Ocean Thermal Energy Conversion (OTEC) ........................ 384 13.4.1 Operating Principles................................................. 385 13.4.2 Operating Sites ......................................................... 386 13.4.3 Other Usages of OTEC ............................................ 387 13.4.4 Barriers to Implementation ...................................... 387 13.5 Growth of Hydrokinetic Energy and OTEC Industries and Cost of Hydrokinetic and OTEC Power ......................... 389 References ........................................................................................ 390 Index ...................................................................................................................... 395 xv Series Preface Green Chemistry and ChemiCal enGineerinG A B ook S erieS By CrC P reSS /T Aylor & F rAnCiS The subject and discipline of chemistry and chemical engineering have encountered a new landmark in the way of thinking about, developing, and designing chemical products and processes. The revolutionary philosophy, termed “green chemistry and chemical engineering,” focuses on the design of products and processes that are con- ducive to reducing or eliminating the use and/or generation of hazardous substances. In dealing with hazardous or potentially hazardous substances, there may be some overlaps and interrelationships between environmental chemistry and green chem- istry. While environmental chemistry is the chemistry of the natural environment and the pollutant chemicals in nature, green chemistry proactively aims to reduce and prevent pollution at its very source. In essence, the philosophies of green chem- istry and chemical engineering tend to focus more on industrial applications and practice rather than academic principles and phenomenological science. However, similar to the chemistry and chemical engineering philosophy, the green chemistry and chemical engineering derives from and builds on organic chemistry, inorganic chemistry, polymer chemistry, fuel chemistry, biochemistry, analytical chemistry, physical chemistry, environmental chemistry, thermodynamics, chemical reaction engineering, transport phenomena, chemical process design, separation technology, automatic process control, and so on. In sum, green chemistry and chemical engi- neering is the rigorous use of chemistry and chemical engineering for pollution pre- vention and environmental protection. The Pollution Prevention Act of 1990 in the United States established a national policy to prevent or reduce pollution at its source whenever feasible. Adhering to the spirit of this policy, the Environmental Protection Agency (EPA) launched its Green Chemistry Program to promote innovative chemical technologies that reduce or eliminate the use or generation of hazardous substances in the design, manufacture, and use of chemical products. The gl