Treatment that melts contaminated soil at 1,400 to 2,000 degrees Celsius into a glass or glass-ceramic monolith, destroying organics by pyrolysis and oxidation and immobilizing metals and radionuclides in a leach-resistant matrix. Available in in-situ (electrode-based) and ex-situ (plasma-arc) forms.
Vitrification is the highest-temperature, most permanent immobilization remedy available. In-situ vitrification (ISV), developed by Battelle in the 1980s, advances electrodes downward through the formation while passing current that melts the soil to 1,600 degrees Celsius. Ex-situ plasma-arc vitrification systems achieve similar temperatures in a melt chamber and are used for asbestos, radioactive waste, and concentrated metal residues.
The product is a glass or glass-ceramic monolith with leaching performance an order of magnitude or more better than cement-based S/S. Energy demand is high (roughly 700 to 1,000 kWh per tonne treated), and applicability is constrained to sites that can justify the cost: high-hazard radioactive or mixed waste, source zones with high metal loading, and decommissioning of nuclear facilities.
Also known as: vitrification, in-situ vitrification, ISV, plasma vitrification.
Dioxins and Furans (PCDD/PCDF): treatment approach
A family of 210 chlorinated tricyclic aromatic congeners — including 2,3,7,8-TCDD — formed as unintended byproducts of combustion, chlorine chemistry, and legacy herbicide manufacture; persistent, bioaccumulative, and destroyed only by high-temperature thermal treatment.
An ex-situ soil treatment process that heats contaminated soil to volatilize and separate organic contaminants from the soil matrix, after which the liberated vapors are captured and treated, usually in a high-temperature oxidizer.
A thermal desorption configuration where the heat source contacts the soil directly inside the rotary unit, delivering high heat-transfer efficiency and supporting higher treatment temperatures.
A thermal desorption configuration where heat is conducted through the wall of the treatment vessel without combustion gases contacting the soil, producing a concentrated, lower-volume vapor stream suitable for condensation and recovery.
Treatment that heats contaminated soil and groundwater in place, typically with electrical resistance, thermal conduction, or steam injection, to volatilize and recover contaminants without excavation. Used where excavation is impractical or where the contaminant zone sits beneath active infrastructure.