Process and apparatus for thermally converting used or waste tires to materials usable as fuels

Claim 1

In a process for converting used or waste tires to liquid and gaseous products, wherein the tires are heated in contact with a hydrocarbon oil at a temperature of 300°-500° C., and the resultant liquid and gaseous products are separated from the undecomposed casings and recovered, the improvement comprising spraying a hydrocarbon oil heated to 350°-500° C. onto whole or coarsely cut tires, using spray means, in an amount of 1.5-4 parts by weight of oil per part by weight of tires, the tires being contained in a container whose walls permit passage of oil therethrough while retaining the tires; condensing volatile liquids produced by decomposition of the tires and recovering the resultant condensate; collecting the oil in a collecting tank after it has flowed over the tires and out of the container; and recirculating at least a portion of the collected oil to the spray means at an hourly rate of 5-100 cubic meters of oil per metric ton of tires, the recirculation being continued for a time sufficient to convert the tires to liquid and gaseous products, leaving the undecomposed casings in the container; whereby less oil and less heat are required than would be required to immerse the tires in a bath of the oil, a higher rate of gum decomposition is achieved, and foam accumulation is reduced.