Abstract: The production of oil by retorting shale and other hydrocarbonaceous and lignocellulosic solid materials is facilitated by retorting in the presence of steam and acetic acid.

Abstract: A continuously operable retort-type processing system for the recovery of petroleum-like products from comminuted oil-bearing shale and other oil-yielding particulate solid materials. The retort portion of the system includes an insulated retort outer shell for a wall jacket-type heat exchanger. Disposed within the retort, all driven from a common axially disposed motor-driven shaft, are a plurality of stirring fingers, wall scrapers and discharge shovels, the latter for use in discharge of spent solid material from the retort. The system envisions burning gases from the process to provide a fluid heat exchange medium as a source of the heat required for the process. The system further includes means for the admixture of steam and acetic acid with the starting particulate materials prior to its introduction into the retort.