industrial ecology approach to management of fly ash from fluidized bed combustion production of slow-release fertilizer and soil conditioner

INDUSTRIAL ECOLOGY APPROACH TO MANAGEMENT OF FLY ASH FROM FLUIDIZED BED COMBUSTION: PRODUCTION OF SLOW-RELEASE FERTILIZER AND SOIL CONDITIONER by Mario Castañeda Muñoz A thesis submitted in partial fulfillment of the requirements for the degree of DOCTOR IN PHILOSOPHY in CIVIL ENGINEERING UNIVERSITY OF PUERTO RICO MAYAGÜEZ CAMPUS 2006 Approved by: Gustavo Martínez Rodríguez, Ph.D Member, Graduate Committee Date Ismael Pagán Trinidad, M.S Member, Graduate Committee Date Jorge Rivera Santos, Ph.D Member, Graduate Committee Date Jaime Benítez, Ph.D President, Graduate Committee Date Eric Harmsen, PhD Representative of Graduate Studies Date Ismael Pagán Trinidad, M.S Chairperson of the Department Date José Mari Mutt, PhD Director of Graduate Studies Date UMI Number: 3220601 UMI Microform 3220601 Copyright 2007 by ProQuest Information and Learning Company All rights reserved This microform edition is protected against unauthorized copying under Title 17, United States Code ProQuest Information and Learning Company 300 North Zeeb Road P.O Box 1346 Ann Arbor, MI 48106-1346 ABSTRACT Coal has been a major energy source since the Industrial Revolution Despite its environmental problems, coal consumption is still growing because of the lack of alternatives such as natural gas and petroleum resources As a result, more than 50 million metric tons of fly ash are generated by the electric utilities in the United States yearly, almost one-third of which is used in a number of applications Alternatives for the reuse of fly ash in the United States and Puerto Rico previously considered are mostly for low-technology uses and they have had limited success Thus, many attempts to utilize the fly ash are currently underway, focusing on the high-technology and high-value areas An alternative for management and final disposal of the fly ash generated at a fluidized bed (FBC) coal-fired power plant which is in harmony with the principles of industrial ecology was thoroughly studied It was demonstrated that the ash can be pelletized by reacting it with a proper binder (KOH or KCl solutions) and sintering the pellets at temperatures between 400 and 600ºC for periods of time ranging from 30 to 120 min, producing in the process a potassium fertilizer and soil conditioner The product, containing about 10% by weight slow-release K2O, was found to be of great potential value for agricultural purposes, especially for, but not limited to, tropical areas The product was also found to be safe from the points of view of health and the environment The transport of certain trace elements leached from the pellets through the soil was simulated using the software package Hydrus-1D ii RESUMEN El carbón mineral sido una fuente mayor de energía desde los comienzos de la Revolución Industrial A pesar de los problemas ambientales que acarrea su uso, el consumo de carbón continúa en aumento debido a la falta de recursos de gas natural y petróleo Como resultado, más de 50 millones de toneladas métricas de cenizas volantes son generadas anualmente por las plantas termoeléctricas de los Estados Unidos, de las cuales aproximadamente una tercera parte es utilizada en varios tipos de aplicaciones Las alternativas para el reuso de las cenizas volantes consideradas previamente en Estados Unidos y Puerto Rico han sido mayormente para aplicaciones de bajo nivel tecnológico y han tenido un éxito limitado Actualmente están bajo estudio diferentes usos para las cenizas, enfocándose estos esfuerzos en áreas de alta tecnología y valor económico Se estudió intensivamente y se optimizó una alternativa para el manejo y disposición final de la ceniza generada en plantas de potencia que queman carbón en lecho fluido (FBC, por sus siglas en inglés) la cual armoniza los principios de la ecología industrial Se demostró que la ceniza puede convertirse en perdigones reaccionándola un agente aglomerador apropiado (soluciones de KOH o KCl) y sinterizando los perdigones a temperaturas entre 400 y 600ºC por periodos de tiempo entre 30 y 120 min, generando en el proceso un fertilizante de potasio y acondicionador de suelos El producto, conteniendo cerca de 10% por peso de K2O de liberación lenta, tiene un gran valor potencial para propósitos agrícolas especialmente en áreas tropicales El producto es seguro desde los puntos de vista de salud y ambiente Se usó el programa Hydrus-1D para estudiar el transporte de los lixiviados a través del suelo iii “No hay mayor virtud en un hombre, que el de aquel que sabe entender y comprender al que no sabe expresar y decir lo que siente” “Cuídate de la libertad, pues te puede dejar sumido(a) en la soledad” “No hay un ser mas peligroso que un justo convencido” Autoría Mario Casteda Moz This thesis is dedicated to my “I’m God your Lord….” To my Mother Rosaura Muñoz for her entirety, My brothers Miguel Antonio, Francisco, Leonardo, and Diego Ferney, My sisters Rosaura, Rubiela, Nubia and Marina, All my nephews and nieces, And, my friend Amira Padilla for her unconditional support iv ACKNOWLEDGEMENTS I wish to dedicate this section to recognize the support of several persons and institutions who collaborated directly and indirectly with my research, during the development of my doctoral studies at the University of Puerto Rico for the period of five years 2002 – 2006 Without their support it would have been impossible for me to finish my work Also I want to express a sincere acknowledgement to my advisor, Dr Jaime Benítez, for counseling and orientation before, during, and after thesis work; and because he gave me the opportunity to conduct research under his supervision I also want to thank the support, advice, and comments that I received from Dr Gustavo Martínez For the assistance obtained from these two persons, I am most grateful Special thanks to Dr Roque Román, Prof Ismael Pagán, and Dr Jorge Rivera Santos for serving on my graduate committee, and reviewing this manuscript Special thanks also to Dr Raúl Zapata for reviewing the manuscript I am grateful to the Civil Engineering Department of the University of Puerto Rico, Mayagüez Campus for their support of me as a Teaching Assistant, and to all professors that contributed to my academic formation v I greatly appreciate the AES Corporation for providing the funding and the resources for the development of this research Thanks are also extended to Carlos Reyes, Millie Maria Torres, and Neil Watlington for their valuable and authorizing the use of the fly ash from AES Also, I wish to address my special thanks to Dr Hans Schellekens, Director of the Geology Department, for sponsoring running the samples on the X-ray diffractometer instrument Most importantly, I specially wish to thank my mother for giving me most valuable advice and each member of my family Indeed, while in the distance they have provided their great love, prayers, and support for me including all the things that I have made in my life My warm thanks to Professor Amira Padilla, for her unconditional friendship and unlimited support during all the phases of this work, helping me to tolerate the difficulties that appear in daily life, and to write this manuscript vi TABLE OF CONTENTS LIST OF TABLES IX LIST OF FIGURES XI INTRODUCTION 1.1 Objectives of the present study .6 1.2 Strategy 1.3 Overview of the Thesis 2.1 THEORETICAL BACKGROUND Introduction .9 2.2 Characteristics of Coal Combustion By-Products 2.2.1 Fly and Bottom Ashes 2.2.2 Fluidized Bed Combustion Wastes 11 2.2.3 Types of Coal Combustion Products .18 2.3 Agricultural Use of Coal Combustion By-Products 19 2.4 Environmental Effects of Coal Combustion By-Products 21 2.5 Ion Movement with the Amendment of Soils .23 2.5.1 Lime and gypsum application to correct soil acidity 26 2.5.2 Solute transport in the unsaturated zone (Simunek, et al., 2005) 35 2.6 Powder Metallurgy (German, 1994) 47 2.7 Slow-Release Fertilizers (Bennett, 1992) 49 2.7.1 Pelletized 49 2.7.2 Chemically Altered 50 2.7.3 Coated 50 2.8 Leaching of Solids in a Cross-Flow Cascade of Stages 52 2.9 Industrial Ecology 55 METHODS AND MATERIALS 58 vii 3.1 Introduction 58 3.2 Experiments 58 3.2.1 Materials 58 3.2.2 Equipment 60 3.2.3 Procedure .64 3.3 Analyses 71 RESULTS AND DISCUSSION 74 4.1 X-Ray Diffraction and X-Ray Fluorescence 74 4.2 pH and Leaching Behavior of the Pellets .80 4.3 Statistical Analysis of Slow-Release Behavior 98 4.4 Compressive Strength: Rupture Modulus Results 101 4.5 Statistical Analysis of Rupture Modulus Results 106 4.6 Trace Elements in Pellets and Leachates .108 4.7 Potential Environmental Impact of the Pellets .116 4.7.1 Potassium fertilizer requirement of plantains 116 4.7.2 Water requirement of plantains .117 4.7.3 Slow-release behavior of aluminum under field conditions 117 4.7.4 Simulation of the fate of the aluminum released on the field 118 4.7.5 Simulation of the fate of boron .123 CONCLUSIONS, RECOMMENDATIONS AND LIMITATIONS 128 REFERENCES 132 APPENDIX A ANALYSIS OF PH VERSUS WASH NUMBER DATA 145 viii List of Tables Tables Page TABLE 2.1 Typical composition of Class F and C ashes as defined by ASTM (Ziemkiewicz and Skousen, 2000) 19 TABLE 3.1 Chemical composition of fly ashes (wt%) 59 TABLE 3.2 Amounts needed for the preparation of solutions of KOH and KCl 66 TABLE 3.3 Experimental design for KOH 4.0N 70 TABLE 3.4 Experimental design for KOH 6.0N 70 TABLE 3.5 Experimental design for KCl 4.0N 70 TABLE 3.6 Experimental design for KCl 5.0N 71 TABLE 3.7 Minimum detection limits (MDL) for analyses 72 TABLE 4.1 Crystalline structures in fly ash and pellets 80 TABLE 4.2 pH of fly ash plus binder solutions 81 TABLE 4.3 pH of binder solutions 81 TABLE 4.4 Summary of leaching behavior of pellets produced using KCl, 4N 83 TABLE 4.5 Summary of leaching behavior of pellets produced using KCl, 5N 84 TABLE 4.6 Summary of leaching behavior of pellets produced using KOH, 4N 85 TABLE 4.7 Summary of leaching behavior of pellets produced using KOH, 6N 86 TABLE 4.8 Fertilizer value of best treatments from the point of view of leaching behavior 87 TABLE 4.11 Hydroxyl ion leaching parameters in cross-flow cascade 92 ix 180 pH Eq pH Non Eq KOH 4.0N.60-600-30-1 12 y = 11,775 - 0,13462x R= 0,92979 y = 10,632 - 0,027926x R= 0,88954 11,5 SRI = 5,110106833 11 q E H p 10,5 10 9,5 10 20 30 40 50 60 n, Wash number Figure A-67 SRI for Treatment KOH 4.0N.60-600-30-1 pH Eq pH Non Eq KOH 4.0N.60-600-30-2 12 y = 11,978 - 0,17654x R= 0,95429 y = 10,583 - 0,021766x R= 0,95181 11,5 SRI = 3,525264395 11 q E H p 10,5 10 9,5 10 20 30 40 50 60 n, Wash number Figure A-68 SRI for Treatment KOH 4.0N.60-600-30-2 181 pH Eq pH Non Eq KOH 4.0N.60-600-60-1 12 y = 11,768 - 0,096538x R= 0,51848 y = 10,616 - 0,022972x R= 0,94664 11,5 SRI = 8,821978233 11 q E H p 10,5 10 9,5 10 20 30 40 50 60 n, Wash number Figure A-69 SRI for Treatment KOH 4.0N.60-600-60-1 pH Eq pH Non Eq KOH 4.0N.60-600-60-2 12 y = 12,109 - 0,16577x R= 0,83343 y = 10,588 - 0,022081x R= 0,95743 11,5 SRI = 11,34558113 11 q E H p 10,5 10 9,5 10 20 30 40 50 60 n, Wash number Figure A-70 SRI for Treatment KOH 4.0N.60-600-60-2 182 pH Eq pH Non Eq KOH 4.0N.60-600-120-1 12 y = 11,788 - 0,11654x R= 0,90347 y = 10,587 - 0,02155x R= 0,97769 11,5 SRI = 9,596775483 11 q E H p 10,5 10 9,5 10 20 30 40 50 60 n, Wash number Figure A-71 SRI for Treatment KOH 4.0N.60-600-120-1 pH Eq pH Non Eq KOH 4.0N.60-600-120-2 12 y = 11,935 - 0,12962x R= 0,85309 y = 10,455 - 0,018578x R= 0,92875 11,5 SRI = 3,263034142 11 q E H p 10,5 10 9,5 10 20 30 40 50 60 n, Wash number Figure A-72 SRI for Treatment KOH 4.0N.60-600-120-2 183 KOH N Treatment pH Eq pH Non Eq KOH 6.0N 30-400-30-1 12,5 y = 12,029 - 0,14206x R= 0,9014 y = 10,299 - 0,018442x R= 0,93732 12 SRI =22,67207771 11,5 q E H p 11 10,5 10 9,5 10 15 20 25 30 35 40 n, Wash Number Figure A-73 SRI for Treatment KOH 6.0N.30-400-30-1 pH Eq pH Non Eq KOH 6.0N.30-400-30-2 12,5 y = 12,309 - 0,14421x R= 0,92012 12 y = 10,474 - 0,025303x R= 0,95214 SRI = 6,987360393 11,5 q E 11 H p 10,5 10 9,5 10 20 30 40 50 n, Wash number Figure A-74 SRI for Treatment KOH 6.0N.30-400-30-2 184 pH Non Eq pH Eq KOH 6.0N.30-400-60-1 12 y = 9,5607 - 0,0052258x R= 0,33072 y = 11,665 - 0,13095x R= 0,89364 11,5 SRI = 5,119754252 q E 11 n o N 10,5 H p 10 9,5 10 20 30 40 50 n, Wash number Figure A-75 SRI for Treatment KOH 6.0N.30-400-60-1 pH Eq pH Non Eq KOH 6.0N.30-400-60-2 12,5 y = 12,29 - 0,14246x R= 0,92625 12 y = 10,029 - 0,0095258x R= 0,63319 SRI = 9,849302474 11,5 q E 11 H p 10,5 10 9,5 10 20 30 40 50 60 70 n, Wash number Figure A-76 SRI for Treatment KOH 6.0N.30-400-60-2 185 pH Eq pH Non eq KOH 6.0N.30-400-120-1 12,5 y = 11,781 - 0,13952x R= 0,86769 12 y = 9,6385 - 0,0069374x R= 0,59403 SRI = 8,567109021 11,5 q E 11 H p 10,5 10 9,5 10 20 30 40 50 60 n, Wash number Figure A-77 SRI for Treatment KOH 6.0N.30-400-120-1 pH Eq pH Non Eq KOH 6.0N.30-400-120-2 12,5 y = 12,174 - 0,13365x R= 0,91966 12 y = 9,8892 - 0,0058129x R= 0,47691 SRI = 13,39603477 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-78 SRI for Treatment KOH 6.0N.30-400-120-2 186 pH Eq pH Non Eq KOH 6.0N.30-600-30-1 13 y = 11,909 - 0,11325x R= 0,92148 y = 9,8853 - 0,0055224x R= 0,389 12 SRI = 44,35139088 q E 11 H p 10 20 40 60 80 100 120 140 n, Wash number Figure A-79 SRI for Treatment KOH 6.0N.30-600-30-1 pH Eq pH Non Eq KOH 6.0N.30-600-30-2 13 y = 12,27 - 0,13032x R= 0,92526 y = 10,173 - 0,0060711x R= 0,46543 12 q E SRI = 25,0773672 11 H p 10 20 40 60 80 100 120 140 n, Wash number Figure A-80 SRI for Treatment KOH 6.0N.30-600-30-2 187 pH Eq pH Non Eq KOH 6.0N.30-600-60-1 13 y = 11,909 - 0,11325x R= 0,92148 y = 9,8849 - 0,0055136x R= 0,433 12 q E SRI = 50,77831283 11 H p 10 20 40 60 80 100 120 140 n, Wash number Figure A-81 SRI for Treatment KOH 6.0N.30-600-60-1 pH Eq pH Non Eq KOH 6.0N.30-600-60-2 13 y = 12,27 - 0,13032x R= 0,92526 y = 10,173 - 0,0060711x R= 0,46543 12 q E SRI = 30,41314921 11 H p 10 20 40 60 80 100 120 140 n, Wash number Figure A-82 SRI for Treatment KOH 6.0N.30-600-60-2 188 pH Eq pH Non Eq KOH 6.0N.30-600-120-1 12,5 y = 12,166 - 0,13175x R= 0,95346 12 y = 10,118 - 0,0065455x R= 0,51239 SRI = 84,90264412 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-83 SRI for Treatment KOH 6.0N.30-600-120-1 pH Eq pH Non Eq KOH 6.0N.30-600-120-2 12,5 y = 12,24 - 0,12341x R= 0,98602 12 y = 10,425 - 0,0075422x R= 0,62584 SRI = 71,18763289 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-84 SRI for Treatment KOH 6.0N.30-600-120-2 189 pH Eq pH Non Eq KOH 6.0N.60-400-30-1 12,5 y = 12,158 - 0,1404x R= 0,91187 12 y = 9,8966 - 0,0070346x R= 0,59383 SRI = 32,50461214 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-85 SRI for Treatment KOH 6.0N.60-400-30-1 pH Eq pH Non Eq KOH 6.0N.60-400-30-2 12,5 y = 12,201 - 0,13635x R= 0,93258 12 y = 9,8982 - 0,0055972x R= 0,61235 SRI = 9,641961304 11,5 q E 11 H p 10,5 10 9,5 20 40 60 80 100 120 140 n, Wash number Figure A-86 SRI for Treatment KOH 6.0N.60-400-30-2 190 pH Eq pH Non Eq KOH 6.0N.60-400-60-1 12 y = 11,922 - 0,12556x R= 0,90946 11,5 y = 9,7264 - 0,0065132x R= 0,45525 SRI = 22,10019822 11 q E 10,5 H p 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-87 SRI for Treatment KOH 6.0N.60-400-60-1 pH Eq pH Non Eq KOH 6.0N.60-400-60-2 12,5 y = 12,204 - 0,14111x R= 0,94255 12 y = 9,9635 - 0,0061196x R= 0,52833 SRI = 10,6043521 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-88 SRI for Treatment KOH 6.0N.60-400-60-2 191 pH Non Eq pH Eq KOH 6.0N.60-400-120-1 12 y = 9,4675 - 0,0014465x R= 0,18073 y = 11,769 - 0,12717x R= 0,9195 11,5 SRI = 3,262590561 q E 11 n o N 10,5 H p 10 9,5 20 40 60 80 100 n, Wash number Figure A-89 SRI for Treatment KOH 6.0N.60-400-120-1 pH Eq pH Non Eq KOH 6.0N.60-400-120-2 12,5 y = 12,199 - 0,14111x R= 0,92107 12 y = 9,8831 - 0,0051678x R= 0,48284 SRI = 9,588953526 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-90 SRI for Treatment KOH 6.0N.60-400-120-2 192 pH Eq pH Non Eq KOH 6.0N.60-600-30-1 12 y = 11,637 - 0,081508x R= 0,89488 11,5 y = 10,108 - 0,0054473x R= 0,54729 SRI = 57,05348665 11 q E 10,5 H p 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-91 SRI for Treatment KOH 6.0N.60-600-30-1 pH Eq pH Non Eq KOH 6.0N.60-600-30-2 12,5 y = 12,015 - 0,10841x R= 0,92896 12 y = 10,434 - 0,006965x R= 0,48104 SRI = 11,43506005 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-92 SRI for Treatment KOH 6.0N.60-600-30-2 193 pH Eq pH Non Eq KOH 6.0N.60-600-60-1 12,5 y = 12,075 - 0,11817x R= 0,92025 12 y = 10,208 - 0,0028846x R= 0,37174 SRI = 178,2017568 11,5 q E 11 H p 10,5 10 9,5 20 40 60 80 100 120 140 n, Wash number Figure A-93 SRI for Treatment KOH 6.0N.60-600-60-1 pH Eq pH Non Eq KOH 6.0N.60-600-60-2 12,5 y = 11,995 - 0,095952x R= 0,92159 12 y = 10,516 - 0,0059649x R= 0,49934 SRI = 31,26649288 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-94 SRI for Treatment KOH 6.0N.60-600-60-2 194 pH Eq pH Non Eq KOH 6.0N.60-600-120-1 12,5 y = 12,251 - 0,12294x R= 0,92657 12 y = 10,483 - 0,0047037x R= 0,46091 SRI = 38,44554281 11,5 q E 11 H p 10,5 10 9,5 20 40 60 80 100 120 140 n, Wash number Figure A-95 SRI for Treatment KOH 6.0N.60-600-120-1 pH Eq pH Non Eq KOH 6.0N.60-600-120-2 12,5 y = 11,975 - 0,096905x R= 0,92017 12 y = 10,586 - 0,0083328x R= 0,6219 ARI = 36,08766545 11,5 q E 11 H p 10,5 10 9,5 8,5 20 40 60 80 100 120 140 n, Wash number Figure A-96 SRI for Treatment KOH 6.0N.60-600-120-2 ... Cascade of Stages, and Industrial Ecology 2.2 Characteristics of Coal Combustion By-Products 2.2.1 Fly and Bottom Ashes The physical, chemical, and mineralogical characteristics of bottom and fly ashes... rates of application (≥ 400 ton ash/ ha), salt injury and B toxicity can occur in plants growing on soils amended with fresh ash (ACAA, 2001) Addition of fly ash to soil can also affect soil and. .. Amendment of Soils In southeastern US and Puerto Rico, many soils are acid and the subsoil is acid and infertile For example, there are 209,894 of soil belonging to the Ultisols order and 64,801 of