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19 METAL RECOVERY WITH A NOVEL ELECTROCHANGE™ PROCESS C.-D. Zhou, Manager of Research E. C. Stortz, Laboratory Manager E. J. Taylor, President R. P. Renz, Manager of Engineering Faraday Technology, Inc. Dayton, Ohio 45420 INTRODUCTION Metals are widely used in various industrial processes. Due to the toxicity of heavy metals, metal containing wastewater must be adequately treated. Currently, a precipitation method is used to treat metal containing wastewater. Even though metals are removed from the water, undesirable sludges are generated as a by-product, which creates new waste disposal problems. Therefore, recovery technologies are needed to recover and reuse metals, eliminating metal sludges. There are several commercially available recovery technologies. They are: (1) elec- trowinning, (2) ion-exchange, (3) reverse osmosis, (4) electrodialysis, and (5) evaporation. Electrowinning and ion-exchange are widely used recovery technologies for treating wastewater contaminated with metals. The advantages of electrowinning include: (1) recovered pure metal, (2) low capital cost, and (3) no chemical addition. However, due to the hydrogen evolution reaction, the current efficiency for electrowinning is low, resulting in high effluent concentration and high power consumption. The approach to improving the electrowinning process is to increase the mass transfer rate and electrode surface area. Ion-exchange can effectively treat low concentration wastewater and no chemicals are needed during the treatment. However, the cost is extremely high when large volumes of wastewater with high initial concentrations are treated. Another metal recovery approach couples electrowinning for high concentration metal removal with an ion-exchange unit for "polishing" of the low concentration metal. A drawback of this approach is the high capital cost associated with the two metal recovery units. In this study, we conducted experiments to recover copper from an ELECTROCHANGE™ system.1 The ELECTROCHANGE™ system integrates the electrowinning and ion-exchange processes into a single unit. The system concentrates copper on ion-exchange resin followed by plating onto electrode materials. Consequently, the advantages of the ELECTROCHANGE™ system include: (1) ion-exchange resin concentrates metal for efficient electrowinning onto electrode material, (2) ion-exchange resin is continuously regenerated in situ, (3) effective treatment of wastewater from high concentration to low concentration, (4) low capital cost, and (5) no chemical addition. Pulse current (PC) is used to enhance mass transfer rate during the ELECTROCHANGE™ metal recovery process. Cost evaluations were conducted for the ELECTROCHANGE™ system and compared to the other commercial metal recovery technologies. A technoeconomic map was obtained to show how this technology is positioned to existing technologies over the treatment rate from 480 to 50,000 gpd and initial copper concentrations from 100 ppm to 1000 ppm. 'ELECTROCHANGE™ is a trademark of Faraday Technology. Inc. 51st Purdue Industrial Waste Conference Proceedings, 1996. Ann Arbor Press. Inc., Chelsea, Michigan 48118. Printed in U.S.A. 167
Object Description
Purdue Identification Number | ETRIWC199619 |
Title | Metal recovery with a novel electrochange process |
Author |
Zhou, C.-D. Stortz, E. C. Taylor, E. J. Renz, R. P. |
Date of Original | 1996 |
Conference Title | Proceedings of the 51st Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://e-archives.lib.purdue.edu/u?/engext,46351 |
Extent of Original | p. 167-174 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Date Digitized | 2009-10-27 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page 167 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Transcript | 19 METAL RECOVERY WITH A NOVEL ELECTROCHANGE™ PROCESS C.-D. Zhou, Manager of Research E. C. Stortz, Laboratory Manager E. J. Taylor, President R. P. Renz, Manager of Engineering Faraday Technology, Inc. Dayton, Ohio 45420 INTRODUCTION Metals are widely used in various industrial processes. Due to the toxicity of heavy metals, metal containing wastewater must be adequately treated. Currently, a precipitation method is used to treat metal containing wastewater. Even though metals are removed from the water, undesirable sludges are generated as a by-product, which creates new waste disposal problems. Therefore, recovery technologies are needed to recover and reuse metals, eliminating metal sludges. There are several commercially available recovery technologies. They are: (1) elec- trowinning, (2) ion-exchange, (3) reverse osmosis, (4) electrodialysis, and (5) evaporation. Electrowinning and ion-exchange are widely used recovery technologies for treating wastewater contaminated with metals. The advantages of electrowinning include: (1) recovered pure metal, (2) low capital cost, and (3) no chemical addition. However, due to the hydrogen evolution reaction, the current efficiency for electrowinning is low, resulting in high effluent concentration and high power consumption. The approach to improving the electrowinning process is to increase the mass transfer rate and electrode surface area. Ion-exchange can effectively treat low concentration wastewater and no chemicals are needed during the treatment. However, the cost is extremely high when large volumes of wastewater with high initial concentrations are treated. Another metal recovery approach couples electrowinning for high concentration metal removal with an ion-exchange unit for "polishing" of the low concentration metal. A drawback of this approach is the high capital cost associated with the two metal recovery units. In this study, we conducted experiments to recover copper from an ELECTROCHANGE™ system.1 The ELECTROCHANGE™ system integrates the electrowinning and ion-exchange processes into a single unit. The system concentrates copper on ion-exchange resin followed by plating onto electrode materials. Consequently, the advantages of the ELECTROCHANGE™ system include: (1) ion-exchange resin concentrates metal for efficient electrowinning onto electrode material, (2) ion-exchange resin is continuously regenerated in situ, (3) effective treatment of wastewater from high concentration to low concentration, (4) low capital cost, and (5) no chemical addition. Pulse current (PC) is used to enhance mass transfer rate during the ELECTROCHANGE™ metal recovery process. Cost evaluations were conducted for the ELECTROCHANGE™ system and compared to the other commercial metal recovery technologies. A technoeconomic map was obtained to show how this technology is positioned to existing technologies over the treatment rate from 480 to 50,000 gpd and initial copper concentrations from 100 ppm to 1000 ppm. 'ELECTROCHANGE™ is a trademark of Faraday Technology. Inc. 51st Purdue Industrial Waste Conference Proceedings, 1996. Ann Arbor Press. Inc., Chelsea, Michigan 48118. Printed in U.S.A. 167 |
Resolution | 300 ppi |
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