The Dehumidification Handbook

1 The Dehumidification Handbook Third Edition ISBN 0-9717887-0-7 Copyright 1989, 2002 and 2019 Munters CorporationThe Dehumidification HandbookThird EditionCopyright 1989, 2002 and 2019 Munters CorporationReuse Of This MaterialFor book reviews and personal educational and professional use, readers are encouraged to excerpt or photocopy and distribute any useful portion of this Handbook , provided that the source of the material is appropriately referenced and the Munters copyright is acknowledged. For electronic distribution or if the material will be included in any printed publication, Munters Corporation must provide written authorization in advance of publication.

2 For those uses, please contact Munters Corporation Marketing Department by mail at 79 Monroe Street, Amesbury, MA 01913, or by email at great care has been taken in the compilation and publication of this book, no warranties either expressed or implied are given in connection with the material. Neither the contributors nor the publisher take any responsibility whatsoever for any claims arising from its use. The entire risk of the use of this information is assumed by the user. However, to improve future editions, the publisher welcomes any and all comments, corrections or suggestions from would like to express our gratitude to Lew G.

3 Harriman III as editor of the first two editions of this book and for guiding this work with interest. Also, we would like to thank the following original contributors and 1989 Editorial Advisory Board members for their work; Enno Abel, Nick Baranov, Bruce Bonner, Steven Brickley, Luiz Felipe de Carvalho, Douglas Kosar, Hansi Kruger, Ralph Lahmon, Milton Meckler, Mohamed Moledina, Terry Penny, Ing. Eugenio E. Sanchez, Daniel Schroeder, James Staunton, Steven Toth, Kenneth Welter, Sumner Weisman, Roland Wimmerstedt, and Jose addition, we d like to acknowledge and give special thanks to Steve Brickley, Jim Judge and Lindsay Judge for their content work and contributions to this (Third) edition of the book.

4 We also extend special thanks to Doug Des Champs for the cover design and book layout of this (Third) edition and Inc. for the printing and CorporationTABLE OF CONTENTS1. INTRODUCTION .. 102. PSYCHROMETRICS .. 12 Dry Bulb Temperature Degrees Fahrenheit .. 15 Relative humidity - Percent of saturation .. 15 Humidity Ratio - Grains of water vapor .. 16 Vapor pressure - Inches of mercury .. 17 Dew point temperature - Degrees Fahrenheit .. 18 Enthalpy - Btu s per pound of air .. 18 Wet-bulb temperature - Degrees Fahrenheit .. 193.

5 METHODS OF DEHUMIDIFICATION .. 22 Cooling-based 24 Desiccant Dehumidifiers .. 29 Liquid spray-tower .. 32 Solid packed tower .. 34 Rotating horizontal bed .. 36 Multiple vertical bed .. 38 Rotating Honeycombe .. 39 Comparing desiccant dehumidifiers .. 40 Choosing between desiccant and cooling 444. APPLICATIONS .. 46 Corrosion Prevention .. 48 Military storage .. 49 Electronics protection .. 49 Power plant 49 Lithium battery production .. 49 Condensation Prevention .. 50 Ice rinks .. 51 Water treatment plants .. 51 Surface preparation & coating.

6 51 Injection molding .. 514. APPLICATIONS (CONTINUED) .. 46 Mold/Fungus Prevention .. 52 Archival storage .. 53 Seed storage .. 53 Cargo protection .. 53 Breweries .. 53 Moisture Regain Prevention .. 54 Candy packaging .. 55 Semiconductor and pharmaceutical clean rooms .. 55 Safety glass laminating .. 55 Composite manufacturing .. 55 Product Drying .. 56 Investment castings .. 57 Plastic resin drying .. 57 Candy coating .. 57 Fish drying .. 57 Dry Cooling .. 58 Supermarkets .. 59 Hotels and motels .. 59 Sick buildings .. 59 Advanced HVAC systems.

7 595. MOISTURE LOAD 60 Selecting Design Conditions .. 62 Moisture Load Sources .. 64 Periodic vs. continuous loads .. 78 Fresh air moisture load .. 78 Sample moisture load calculations .. 81 Warehouse dehumidification .. 82 Glass lamination room .. 866. DESICCANT DEHUMIDIFIER PERFORMANCE .. 92 Operating Variables .. 941. Process inlet moisture .. 962. Process inlet temperature .. 963. Air velocity through the process side .. 974. Air temperature entering reactivation .. 985. Moisture of air entering reactivation .. 996. Velocity of air through reactivation.

8 1007. Amount of desiccant presented to the airstream .. 1028. Desiccant sorption and desorption characteristics .. 1037. SYSTEM DESIGN .. 106 Passive storage - Museum Example .. 109 Step One Define the purpose of the project .. 109 Step Two Establishing control levels and tolerances .. 110 Step Three Calculate heat and moisture loads .. 110 Step Four Size the components to remove the loads .. 111 Step Five Select the control system .. 112 Passive Storage - Military Example .. 114 Active Storage - Refrigerated Warehouse Example.

9 119 Commercial HVAC - Supermarket 129 Industrial HVAC - Pharmaceutical Tableting .. 139 Product Drying - Candy Coating Example .. 1508. OPTIMIZING MIXED SYSTEMS .. 162 Example Case Description .. 164 System 1 Dry the make-up air only .. 164 System 2 Pre-cool the make-up air and dry the blend with a desiccant unit .. 166 System 3 Pre-cool the blended air before it enters the desiccant unit .. 167 System 4 - Eliminate all pre-cooling and remove all moisture with desiccants .. 168 Comparing 1709. HUMIDITY & MOISTURE INSTRUMENTATION.

10 174 Duty Cycle & Operating Environment .. 177 Instrument Functions .. 178 Repeatability vs. Accuracy .. 180 Relative Humidity Sensors .. 180 Mechanical expansion hygrometer .. 180 Electronic expansion hygrometer .. 181 Electronic capacitance 182 Electronic resistive sensor .. 182 Psychrometric instruments .. 183 Absolute Humidity Sensors .. 185 Gravimetric train .. 185 Condensation hygrometers .. 185 Aluminum oxide sensors .. 186 Salt equilibrium sensors .. 187 Electrolytic hygrometers .. 188 Material Moisture Content Sensors.