Off-Gas Treatment Technologies for Soil Vapor Extraction Systems: State of the Practice EPA-542-R-05-028 March 2006 Off-Gas Treatment Technologies for Soil Vapor Extraction Systems: State of the Practice March 2006 Prepared by: Office of Superfund Remediation and Technology Innovation Office Solid Waste and Emergency Response U.S. Environmental Protection Agency Off-Gas Treatment Technologies for Soil Vapor Extraction Systems: State of the Practice CONTENTS Section Page ACRONYMS AND ABBREVIATIONS.......................................................................................................vi NOTICE AND DISCLAIMER ....................................................................................................................viii ACKNOWLEDGMENT ...............................................................................................................................ix EXECUTIVE SUMMARY ...................................................................................................................... ES-1 1.0 INTRODUCTION ......................................................................................................................... 1-1 1.1 Purpose........................................................................................................................... 1-1 1.2 Document Structure........................................................................................................ 1-2 1.3 Sources of Information ................................................................................................... 1-2 1.4 Types of Environmental Remediation Systems ............................................................ 1-3 1.5 Summary of Off-Gas Treatment Technologies Evaluated............................................ 1-3 1.5.1 Thermal Treatment............................................................................................ 1-3 1.5.2 Adsorption.......................................................................................................... 1-4 1.5.3 Biofiltration ......................................................................................................... 1-4 1.5.4 Emerging Technologies..................................................................................... 1-4 1.5.4.1 Non-Thermal Plasma.......................................................................... 1-5 1.5.4.2 Photolytic and Photocatalytic Technologies ...................................... 1-5 1.5.4.3 Membrane Separation ........................................................................ 1-5 1.5.4.4 Other Technologies............................................................................. 1-5 1.6 Evaluation Criteria .......................................................................................................... 1-6 2.0 BACKGROUND .......................................................................................................................... 2-1 2.1 State of Practice for Off-Gas Treatment........................................................................ 2-1 2.2 History of Soil Vapor Extraction ..................................................................................... 2-1 2.3 Soil Vapor Extraction and Multi-Phase Extraction Treatment Systems ....................... 2-2 2.3.1 Treatment System Components....................................................................... 2-2 2.3.2 Treatment System Operations.......................................................................... 2-4 2.4 Contaminant Sources and Off-Gas Characteristics...................................................... 2-5 2.5 Regulatory Requirements .............................................................................................. 2-7 3.0 THERMAL TREATMENT TECHNOLOGIES ............................................................................ 3-1 3.1 Thermal Oxidation .......................................................................................................... 3-1 3.1.1 Technology Description..................................................................................... 3-2 3.1.1.1 Direct-Flame Thermal Oxidizers......................................................... 3-3 3.1.1.2 Flameless Thermal Oxidizers ............................................................. 3-3 3.1.1.3 Catalytic Oxidizers .............................................................................. 3-5 3.1.1.4 Hybrid Thermal/Catalytic Oxidizer Systems ...................................... 3-5 3.1.1.5 Heat Recovery..................................................................................... 3-6 3.1.2 Applicability ........................................................................................................ 3-8 3.1.3 Limitations........................................................................................................ 3-10 3.1.4 Performance .................................................................................................... 3-11 3.1.5 Engineering Considerations............................................................................ 3-14 3.1.5.1 Design Issues.................................................................................... 3-14 3.1.5.2 Operating Issues ............................................................................... 3-15 3.1.6 Residuals Management .................................................................................. 3-15 3.1.6.1 Products of Complete Combustion .................................................. 3-15 3.1.6.2 Products of Incomplete Combustion ................................................ 3-16 i March 2006 Off-Gas Treatment Technologies for Soil Vapor Extraction Systems: State of the Practice CONTENTS (Continued) Section Page 3.1.7 Cost and Economics ....................................................................................... 3-18 3.1.7.1 Capital Cost....................................................................................... 3-18 3.1.7.2 Operating Cost .................................................................................. 3-19 3.1.8 Developmental Status ..................................................................................... 3-21 3.2 Internal Combustion Engines....................................................................................... 3-21 3.2.1 Technology Description................................................................................... 3-22 3.2.2 Applicability ...................................................................................................... 3-22 3.2.3 Limitations........................................................................................................ 3-23 3.2.4 Performance .................................................................................................... 3-23 3.2.5 Engineering Considerations............................................................................ 3-24 3.2.6 Residuals Management .................................................................................. 3-24 3.2.7 Cost and Economics ....................................................................................... 3-25 3.2.8 Developmental Status ..................................................................................... 3-25 4.0 ADSORPTION TECHNOLOGIES.............................................................................................. 4-1 4.1 Activated Carbon Adsorption ......................................................................................... 4-1 4.1.1 Technology Description..................................................................................... 4-2 4.1.2 Applicability ........................................................................................................ 4-4 4.1.3 Limitations.......................................................................................................... 4-4 4.1.4 Performance ...................................................................................................... 4-6 4.1.5 Engineering Considerations.............................................................................. 4-6 4.1.6 Residuals Management .................................................................................... 4-8 4.1.7 Cost and Economics ......................................................................................... 4-8 4.1.8 Developmental Status ....................................................................................... 4-9 4.2 Zeolite Adsorption........................................................................................................... 4-9 4.2.1 Technology Description..................................................................................... 4-9 4.2.2 Applicability ...................................................................................................... 4-10 4.2.3 Limitations........................................................................................................ 4-12 4.2.4 Performance .................................................................................................... 4-12 4.2.5 Engineering Considerations............................................................................ 4-14 4.2.6 Residuals Management .................................................................................. 4-15 4.2.7 Cost and Economics ....................................................................................... 4-16 4.2.8 Developmental Status ....................................................................................