Hazardous waste is treated by shredding and then passing the material through an enclosure by means of a conveyor through direct steam impingement. The enclosure is maintained at a pressure greater than or equal to atmospheric pressure in order to maintain steam temperature at or above 212°F. Pressure locks are positioned at an inlet and discharge of the enclosure. The pressure locks allow transport of waste material into and out of the enclosure while maintaining a pressure differential between the interior and exterior of the enclosure.
