_STP_861-1984.pdf

THE CHEMISTRY AND TECHNOLOGY OF GYPSUM A symposium sponsored by ASTM Committee C-11 on Gypsum and Related Building Materials and Systems Atlanta,GA,14-15 April 1983 ASTM SPECIAL TECHNICAL PUBLICATION 861 Richard A.Kuntze,Ontario Research Foundation,editor ASTM Publication Code Number(PCN)04-861000-07 1916 Race Street,Philadelphia,PA 19103 T h i s One Q TJLL-8J0-NL7S rial Library of Congress Cataloging in Publication Data The Chemistry and technology of gypsum.(ASTM special technical publication;861)ASTM publication code number(PCN)04-861000-07.Includes bibliographies and index.1.GypsumCongresses.I.Kuntze.Richard A.II.ASTM Committee C-11 on Gypsum and Related Building Materials and Systems.III.Series.TA455.G9C48 1984 666.92 84-70880 ISBN 0-8031-0219-4 Copyright by AMERICAN SOCIETY FOR TESTING AND MATERIALS 1984 Library of Congress Catalog Card Number:84-70880 NOTE The Society is not responsible,as a body,for the statements and opinions advanced in this publication.Primed in Ann Artxx.Ml Scpttmker I9S4 Copyrighted material Foreword The symposium on The Chemistry and Technology of Gypsum and Gypsum Products was presented at Atlanta,GA,14-15 April 1983.The symposium was sponsored by ASTM Committee C-11 on Gypsum and Related Building Materials and Systems.Richard A.Kuntze.Ontario Research Foundation,presided as chairman of the symposium and is editor of the publication.Copyrighted material Related ASTM Publications Masonry:Materials,Properties,and Performance,STP 778(1982).04-778000-07 Extending Aggregate Resources,STP 774(1982),04-774000-08 Cement StandardsEvolution and Trends,STP 663(1979),04-663000-07 Significance of Tests and Properties of Concrete and Concrete-Making Materials,STP 169B(1978),04-169020-07 Copyrighted material A Note of Appreciation to Reviewers The quality of the papers that appear in this publication reflects not only the obvious efforts of the authors but also the unheralded,though essential,work of the reviewers.On behalf of ASTM we acknowledge with appreciation their dedication to high professional standards and their sacrifice of time and effort.ASTM Committee on Publications Copyrighted material ASTM Editorial Staff Janet R.Schroeder Kathleen A.Greene Rosemary Horstman Helen M.Hoersch Helen P.Many Allan S.Kleinberg Susan L.Gebremedhin Copyrighted material Contents Introduction Physical Testing of Gypsum Board Per ASTM C 473 ROBKRT F-.ACKKR Gypsum Analysis with the Polarizing Microscope OFOROF W.f.RF.FN 22 The Effect of Sorhed Water on the Determination of Phase Composition of CaSQ4 H;Q Systems by Various MethodsDANICA H.TIIRK AND I.ARBI BOUNINI 48 A Simple Apparatus for Measurement of the Hydration Ratio of Plasters and Plaster RocksETIESNK KARMA/SIN 52 Determination of Sulfur Trioxide in Gypsums,GOSWAMI AND 1),CHANDRA 62 Rapid Multielement Analysis of Gypsum and Gypsum Products by X-Ray Fluorescence SpectroscopyVLADIMIR KIX MAN 72 The Relationship Between Water Demand and Particle Size Distribution of StuccoI VDIA M mrKFVirH AMI RICHARD A.KinrrzE Retardation of Gypsum Plasters with Citric Acid:Mechanism and PropertiesTHOMAS KOSLOWSKI AND UDO LUDWIG Byproduct GypsumJEAN W.PRESSLER 84 97 105 Assessment of Environmental Impacts Associated with Phosphogypsum in FloridaALEXANDER MAY AND JOHN W.SWEENEY U 6 Copyri Evaluation of Radium and Toxic Element Leaching Characteristics of Florida Phosphogypsum StockpilesAU-XANDER MAY AND JOHN W.SWI-KNI-V 140 Drying and Agglomeration of Flue Gas GypsumKRANZ wiRSCHINfi UM)Summary 173 Index LZ7 Copyrighted material Introduction Recent advances in gypsum chemistry,analytical techniques,and manufac-turing technologies have raised a number of issues of concern to producers and users of gypsum products alike.For example,the analysis of gypsum and gypsum products as covered by ASTM standards is based almost entirely on wet chemical methods.However,modern instrumental methods are now used routinely in most laboratories and institutions.They are capable of determining constituents and impurities of gypsum and its dehydration products more accurately and reliably than conventional methods.In addition,by-product gypsums are increasingly considered as raw material in the manufacture of gypsum products as partial or complete replacement of natural gypsum.Present ASTM standards do not deal with these synthetic ma-terials,which provide a number of analytical problems because of the presence of unusual impurities not normally found in natural gypsums.For the same reason,the manufacture and application of building materials containing by-product gypsums is affected by serious difficulties.In order to address these questions and problems,this symposium was spon-sored by ASTM Committee C-l 1 on Gypsum and Related Building Materials and Systems.The symposium was intended to provide a forum for discussions of theories,test methods and analyses,and basic information on gypsum and its products.Richard A.Kuntze Ontario Research Foundation,Sheridan Park.Missis&auga.Ontario.Ca