Thermal remediation is the family of soil, sediment, and water cleanup technologies that use heat to mobilize, destroy, or recover contaminants. It includes thermal desorption, high-temperature oxidation, in-situ thermal treatment, and pyrolysis, and is the recognized permanent solution for PFAS, dioxins, PCBs, and persistent hydrocarbons.
Thermal remediation is an umbrella term covering every cleanup approach that uses controlled heat as the primary mechanism for removing or destroying contaminants. Unlike containment, soil washing, or land disposal, thermal methods change the contaminant itself: long carbon chains crack, chlorine-carbon bonds break, and fluorinated compounds finally mineralize. That is why regulators worldwide treat thermal remediation as the benchmark for permanent destruction of persistent organic pollutants.
The category spans four main process families. Thermal desorption heats excavated soil to volatilize organic contaminants without combusting the soil itself, then routes the vapor to a thermal oxidizer for destruction. In-situ thermal remediation uses electrodes, conductive heaters, or steam to heat the subsurface in place, recovering vapor through extraction wells. Pyrolysis converts feedstocks such as tires, plastics, or biosolids in an oxygen-free reactor, breaking them into char, oil, and gas. Direct high-temperature incineration is reserved for the most concentrated waste streams.
Choosing the right thermal remediation approach depends on contaminant type, soil matrix, depth, site access, and regulatory target. PFAS-impacted soils require the upper end of the temperature range (1,100 degrees Celsius and above) with proven destruction and removal efficiency. Hydrocarbons and most semi-volatile organics treat reliably at 320 to 600 degrees Celsius. Nelson operates one of the largest mobile thermal remediation fleets globally, deploying the appropriate process train to the site rather than long-hauling contaminated material to a central facility.
Also known as: thermal soil remediation, thermal treatment, thermal soil treatment, thermal remediation services, thermal remediation technology.
Thermal remediation is the use of controlled heat to destroy or recover contaminants in soil, sediment, and water. It covers thermal desorption, high-temperature oxidation, in-situ thermal treatment, and pyrolysis, and is the recognized permanent solution for PFAS, dioxins, PCBs, and persistent hydrocarbons.
Soil or vapor is heated to a target temperature long enough to volatilize contaminants out of the matrix or to break their chemical bonds entirely. The contaminant fraction is then either captured for recovery or destroyed in a secondary high-temperature oxidizer, leaving treated material that can be returned to the site.
Thermal remediation handles PFAS, dioxins, PCBs, polycyclic aromatic hydrocarbons, BTEX, chlorinated solvents, petroleum hydrocarbons across all fractions, and mixed industrial wastes that are unsuitable for biological or chemical treatment.
For persistent contaminants, yes. Landfilling moves the liability rather than resolving it. Thermal remediation destroys the contaminant itself, eliminates long-term monitoring obligations, and allows treated soil to be returned to productive use on the original site.
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.