Thermal desorption is an ex-situ treatment technology that utilizes heat to increase the volatility of contaminants such that they can be removed from a solid matrix: typically, soil, sludge, filter cake, or drill cuttings. Desorbers are designed as a separation technology to remove organic compounds from such matrices without thermally destroying them. The volatilized contaminants are then either collected or thermally destroyed in secondary treatment units. A thermal desorption system therefore has two major components; the desorber itself and the off-gas treatment system.
Thermal desorption is a thermal soil remediation technique that has been utilized at several hundred environmental remediation projects world wide. As a mature technology, thermal soil remediation performance can be predicted with a high degree of confidence.
Two Basic Designs
Thermal desorption systems can be stationary facilities or mobile units and are comprised of two general categories: Direct-Fired, and Indirect-Fired. There are significant differences between direct and indirect fired units, and many variations of each type. Determining the best suited unit for a particular application requires an understanding the characteristics of the material to be treated and the applicable regulatory requirements.