Springer Theses Recognizing Outstanding Ph.D. Research For furthervolumes: http://www.springer.com/series/8790 Aims and Scope The series ‘‘Springer Theses’’ brings together a selection of the very best Ph.D. theses from around the world and across the physical sciences. Nominated and endorsed by two recognized specialists, each published volume has been selected for its scientific excellence and the high impact of its contents for the pertinent fieldofresearch.Forgreateraccessibilitytonon-specialists,thepublishedversions includeanextendedintroduction,aswellasaforewordbythestudent’ssupervisor explaining the special relevance of the work for the field. As a whole, the series will provide a valuable resource both for newcomers to the research fields described, and for other scientists seeking detailed background information on specialquestions.Finally,itprovidesanaccrediteddocumentationofthevaluable contributions made by today’s younger generation of scientists. Theses are accepted into the series by invited nomination only and must fulfill all of the following criteria • They must be written in good English. • The topic should fall within the confines of Chemistry, Physics and related interdisciplinary fields such as Materials, Nanoscience, Chemical Engineering, Complex Systems and Biophysics. • The work reported in the thesis must represent a significant scientific advance. • Ifthethesisincludespreviouslypublishedmaterial,permissiontoreproducethis must be gained from the respective copyright holder. • They must have been examined and passed during the 12 months prior to nomination. • Each thesis should include a foreword by the supervisor outlining the signifi- cance of its content. • The theses should have a clearly defined structure including an introduction accessible to scientists not expert in that particular field. B. Ambedkar Ultrasonic Coal-Wash for De-Ashing and De-Sulfurization Experimental Investigation and Mechanistic Modeling Doctoral Thesis accepted by Indian Institute of Technology Madras, Chennai, India 123 Author Supervisor Dr. B.Ambedkar Dr. R.Nagarajan Department of Chemical Engineering Department of Chemical Engineering Indian Instituteof Technology-Madras Indian Instituteof Technology-Madras Chennai Chennai India India e-mail: [email protected] e-mail: [email protected] ISSN 2190-5053 e-ISSN 2190-5061 ISBN 978-3-642-25016-3 e-ISBN978-3-642-25017-0 DOI 10.1007/978-3-642-25017-0 SpringerHeidelbergDordrechtLondonNewYork LibraryofCongressControlNumber:2011941669 (cid:2)Springer-VerlagBerlinHeidelberg2012 Thisworkissubjecttocopyright.Allrightsarereserved,whetherthewholeorpartofthematerialis concerned,specificallytherightsoftranslation,reprinting,reuseofillustrations,recitation,broadcasting, reproductiononmicrofilmorinanyotherway,andstorageindatabanks.Duplicationofthispublication orpartsthereofispermittedonlyundertheprovisionsoftheGermanCopyrightLawofSeptember9, 1965,initscurrentversion,andpermissionforusemustalwaysbeobtainedfromSpringer.Violations areliabletoprosecutionundertheGermanCopyrightLaw. Theuseofgeneraldescriptivenames,registerednames,trademarks,etc.inthispublicationdoesnot imply, even in the absence of a specific statement, that such names are exempt from the relevant protectivelawsandregulationsandthereforefreeforgeneraluse. Printedonacid-freepaper SpringerispartofSpringerScience+BusinessMedia(www.springer.com) Dedicated to my Parents and Teachers Parts of this thesis have been published in the following journal articles: 1. R. Nagarajan, B. Ambedkar, S. Gowrisankar and S. Somasundaram, ‘‘Devel- opment of Predictive Model for Fly-ash Erosion Phenomena in Coal-Burning Boilers’’,Wear,267(2009),122–128. 2. B. Ambedkar, R. Nagarajan and S. Jayanti ‘‘Ultrasonic Coal-Wash for De-Sulfurization’’, ‘‘Ultrasonics Sonochemistry’’ 18, (2011), 718–726. 3. B.Ambedkar,T.N.Chintala,R.NagarajanandS.Jayanti,‘‘FeasibilityofUsing Ultrasound-AssistedProcessforSulfurandAshRemovalfromCoal’’,‘‘Chemical EngineeringandProcessing:ProcessIntensification’’50,(2011),236–246. 4. B. Ambedkar, R. Nagarajan and S. Jayanti ‘‘Investigation of High Frequency, High-IntensityUltrasonicsforSizeReductionandWashingofCoalinAqueous Medium’’,‘‘IndustrialEngineeringandChemistryResearch’’journal.(InPress) vii Supervisor’s Foreword Dr. Ambedkar’s thesis work has resulted in four papers, several conference pre- sentations, and an ‘‘Outstanding Thesis’’ award. This comes as no surprise to me. Bothintermsofthequantumofworkanditsquality,thisdissertationisamongthe best in its breed. While ‘‘clean coal technology’’ is on everyone’s wish-list, few have identified the relevant technologies. Removal of ash and sulfur from Indian coals prior to combustion using high-intensity acoustic fields is a novel concept with the promise of high throughput and cost efficiency. By means of well- designed experiments and sound analytical reasoning, Dr. Ambedkar has enun- ciated a path to follow. By focusing on Indian coals, this work becomes of immediate national relevance. While most Indian coals do have high ash content and low sulfur, there are exceptions; also, increasingly, foreign and Indian coals are being blended and used in power plants. Hence, simultaneous de-ashing and de-sulfurizationbecomeacriticalneed.CoalwasheriesbeingoperatedinIndiaare unabletocleancoalaggressively,beingdesignedprimarilytoremoveloosely-held dust, dirt and other debris. But more of these are being brought on-line regularly. This investigation paves the way for optimizing the design of coal washeries for maximum effectiveness with minimum cost and pollutant discharge. This is seminalwork with potential for significant impact to the practice of coal washing in India. Chennai, September 2011 R. Nagarajan ix