Flameless Thermal Oxidation
Flameless Thermal Oxidation is a destructive technology for off-gas treatment of volatile organic compounds( VOCs) and semi-volatile organic compounds (SVOCs). The process converts aromatic and chlorinated VOCs to carbon dioxide, water, and hydrogen chloride without exposing the vapors to a flame. The technology achieves uniform thermal oxidation of VOCs using a heated packed-bed reactor filled with ceramic pieces. The vapors are oxidized when they come into contact with the heated bed of ceramic pieces. Temperatures are typically maintained at 1600¡-1850¡ Fahrenheit.
Limitations and Concerns
Products of incomplete combustion (PICs), which could be emitted to the atmosphere, are a major concern with this technology. Flames vary in temperature. The flameless oxidizer provides a controllable uniform heating zone to control this variable. However, temperature variation is only one culprit in the formation of PICs.
Dioxins and furans are unavoidably created in the oxidation process. Unless they are further captured, they are emitted to the environment. Some dioxins and furans are toxic in the parts per trillion range. There are no regulatory limits for dioxin and furan emissions, except for municipal and medical waste incinerators. These are technology-based, not health-based.
The Flameless Thermal Oxidizer is a high-energy user. It is more energy efficient when treating compounds that produce high temperatures during combustion (e.g., petroleum hydrocarbons) and the heat is re-circulated to enhance efficiency.
The Flameless Thermal Oxidizer destroys VOCs and SVOCs in off-gases from many sources including VOCs, petroleum hydrocarbons, and methylene chloride emissions generated during pesticide production. Recently, it was demonstrated in conjunction with the TerraTherm the Thermal Blanket process, which treats polychlorinated biphenyl (PCB) vapors.
Technology Development Status
The Flameless Oxidizer is a commercial technology offered by Thermatrix, Inc. A full-scale demonstration was conducted by the Department of Energy (DOE) at the Savannah River Site, South Carolina. The Navy demonstrated it in conjunction with the Thermal Blanket at Mare Island Naval Shipyard, California.
Other Resources and Demonstrations
See the description of the Thermal Blanket.
See http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=ADA382609&Location=U2&doc=GetTRDoc.pdf and http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A382616&Location=U2&doc=GetTRDoc.pdf for demonstrations at Lowry AFB (CO) and Air Force Plant 4 (TX), respectively.
See http://www.selasfluid.com/international/web/le/us/likelesfus.nsf/docbyalias/Flameless_Thermal for product information.