Granular bed heating method

Methods and apparatus for roasting a product with a heated granular bed are disclosed. A granular bedding, heat transfer material such as salt or the like contained within a rotatable heating chamber is directly exposed to a heat source which directs heat into the interior of the heating chamber. Heated granular material is then conveyed to a separate product roasting chamber and mixed with incoming particles of a product to be roasted. Internally disposed auger and flighting means facilitate movement of the commingled granular material and product through the roasting bin in response to rotation thereof. Separation means at the output of the roasting bin separates the processed product from the granular heating medium, and continuously returns the granular material to the heating bin for repetition of the process cycle. In one form of the invention the heating chamber is coaxially disposed internally of the rotatable roasting chamber to maximize thermal efficiency. In an alternative embodiment, commingled product and granular material are heated together in a rotatable chamber.