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Microbubble Treatment of Gas Supersaturated Water MICROBUBBLE TREATMENT OF GAS SUPERSATURATED WATER Contract No. GS-23F-0339K/01PE810319 Desalination and Water Purification R&D Program Report No. 70 December 2001 U.S. Department of Interior Bureau of Reclamation Denver Office Technical Service Center Environmental Resources Team Water Treatment Engineering and Research Group MICROBUBBLE TREATMENT OF GAS SUPERSATURATED WATER Mark A. Lichtwardt ARCADIS G&M, Inc. Highlands Ranch, Colorado Co-Author Andrew Murphy Bureau of Reclamation Denver, Colorado Contract No. GS-23F-0339K/01PE810319 Desalination and Water Purification R&D Program Report No. 70 December 2001 U.S. Department of Interior Bureau of Reclamation Denver Office Technical Service Center Environmental Resources Team Water Treatment Engineering and Research Group Mission Statements U.S. Department of the Interior The mission of the Department of the Interior is to protect and provide access to our Nation’s natural and cultural heritage and honor our trust responsibilities to tribes. Bureau of Reclamation The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. Disclaimer The information contained in this report regarding commercial products or firms may not be used for advertising or promotional purposes and is not to be construed as an endorsement of any product or firm by the Bureau of Reclamation. The information contained in this report was developed for the Bureau of Reclamation; no warranty as to the accuracy, usefulness, or completeness is expressed or implied. Acknowledgements This work was financially supported by the U.S. Department of Interior, Bureau of Reclamation under Contract No. GS-23F-0339K/01PE810319. The project team acknowledges the Bureau of Reclamations’ Desalination and Water Purification R&D Program, the Water Treatment Engineering and Research Group, the Denver Research Office, and the PN Region for their support of the project, and would like to especially thank Dan Gonzales, the staff at Grand Coulee Dam, and the Alamosa Field Office for their assistance with data collection and field-testing. Table of Contents List of Tables.....................................................................................................................iii List of Figures...................................................................................................................iv Glossary.............................................................................................................................. v EXECUTIVE SUMMARY............................................................................................... 1 1. INTRODUCTION..................................................................................................... 5 1.1. Gas Bubble Disease............................................................................................. 5 1.2. Regulatory Considerations .................................................................................. 6 1.3. Description of Proposed Treatment Method ....................................................... 6 1.4. Scope of Work..................................................................................................... 7 1.5. Report Organization ............................................................................................ 8 2. CONCLUSIONS AND RECOMMENDATIONS.................................................. 9 2.1 Treatment Process Development Phase .............................................................. 9 2.2 Test and Evaluation Phase................................................................................. 10 3. TREATMENT PROCESS DEVELOPMENT .....................................................12 3.1 Automated Generation of Gas-Supersaturated Water....................................... 12 3.2 Generation of Microbubbles.............................................................................. 13 3.2.1 Hollow-Fiber Membranes ......................................................................... 13 3.2.2 Cylindrical Diffusers................................................................................. 13 3.2.3 Flat-Plate Diffusers ................................................................................... 13 3.3 Optimum Microbubble Size..............................................................................14 3.4 Preliminary Laboratory Testing ........................................................................ 15 3.4.1 Diffuser Pore Size ..................................................................................... 15 3.4.2 Surface Tension......................................................................................... 15 3.4.3 Density of Gas........................................................................................... 16 3.5 Preliminary Field Testing.................................................................................. 16 3.5.1 Site Selection & Test Preparation ............................................................. 16 3.5.2 Testing Procedures .................................................................................... 17 3.5.3 Preliminary Demonstration ....................................................................... 17 3.5.4 Naturally Occurring Gases........................................................................ 18 3.5.5 Comparison of Diffusers ........................................................................... 18 3.5.6 Comparison of Treatment Gases............................................................... 18 3.6 Summary of Results ..........................................................................................19 4. TEST AND EVALUATION................................................................................... 20 4.1 Correlation Between Dissolved Gases .............................................................. 20 4.2 Investigation of GBD ........................................................................................ 20 4.3 Thermodynamic Analysis of the Treatment Process......................................... 23 4.4 Columbia River Data......................................................................................... 23 4.4.1 Historical and Real-Time TDG Measurements......................................... 23 4.4.2 DO Data..................................................................................................... 24 4.5 Variables of Interest .......................................................................................... 24 4.5.1 Dissolved Gas Concentrations .................................................................. 24 4.5.2 Ambient Conditions/Properties................................................................. 24 4.5.3 River Conditions....................................................................................... 26 i 4.5.4 Treatment Variables .................................................................................. 26 4.6 Laboratory Testing ............................................................................................ 27 4.6.1 Diffuser Modification................................................................................ 27 4.6.2 Additional Diffuser Testing ...................................................................... 27 4.7 Field Testing...................................................................................................... 27 4.7.1 Site Selection............................................................................................. 27 4.7.2 Environmental Documents/Job Hazard Analysis...................................... 28 4.7.3 Tests .......................................................................................................... 28 4.8 Oxygen Enriching Techniques.......................................................................... 29 4.8.1 Pressure Swing Adsorption ....................................................................... 30 4.8.2 Vacuum Swing Adsorption....................................................................... 30 4.8.3 Cryogenics................................................................................................. 31 4.8.4 Membrane Separation ............................................................................... 31 4.9 Columbia River Design Criteria........................................................................ 32 4.10 Computer Modeling.......................................................................................... 32 4.10.1 Performance Model................................................................................... 32 4.10.2 Cost Model................................................................................................ 33 5. REFERENCES........................................................................................................ 34 Appendices Appendix A: Dissolved Gas Equations Appendix B: Air Sample Record – Analysis of Gas Sample Collected Under Water at the Franklin Eddy Canal, Alamosa, Colorado Appendix C: Preliminary Laboratory and Field Test Data/Plots Appendix D: Test and Evaluation Data/Plots Appendix E: Preliminary Performance/Cost Models Appendix F: Unit Conversions ii List of Tables Table 1: Field-Testing Equipment and Measured Parameters . 18 Table 2: Relationship Between Variables of Interest . 25 Table C-1: Laboratory Comparison of Air and Oxygen as a Treatment Gas . App. C
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