A number of technologies have been widely applied for removal of VOCs from off-gas streams. However, the application of these technologies to off-gases from site remediation may be quite limited. Biofiltration has been widely applied for VOC destruction in Europe and Japan, but it has only recently been used in the United States. Catalytic and thermal oxidation are widely used for the destruction of gas-phase VOCs in U.S. industry, yet have only limited applications to site remediation of off-gases. Vapor phase carbon adsorption has been the VOC removal technology most commonly used for site remediation off-gases. Carbon adsorption, however, does not destroy the VOCs, so that additional destruction or disposal is required. The following factors may affect the effectiveness and cost of the various technologies: VOC concentration, VOC species, presence of halogenated VOCs, presence of catalyst poisons, particulate loading, moisture content, gas flow rate, and ambient temperature.

Available air emissions/off-gas treatment technologies include biofiltration, high energy destruction, membrane separation, nonthermal plasma, oxidation, scrubbers, and vapor phase carbon adsorption. These processes are discussed in Section 4 . Completed air emissions/off-gas treatment projects are shown in Table 3-17.