Waste rubber is disposed of using vertical distillation pyrolysis column. Rubber with a particle size of less than 1 inch and inert aggregate material with a particle size of 3/4-1 inch is charqed into the column and passed downwardly into a preheating zone at 200-400 deg.C to form a preheated charge heated by the sensible heats of the aggregate and volatile matter leaving the column. The charge is moved downwardly into a heating and distillation zone at 400-500 deg.C where it is heated sufficiently by the upwardly moving gases to cause distillation of volatiles and thermal decomposition of the rubber. Further downward movement into a precombustion zone at 500-900 deg.C occurs where the residual rubber is pyrolysed to a carbonaceous residue before entering a combustion zone at 800-1100 where auxiliary gaseous fuel and air is introduced at a rate sufficient to fluidise the mixt. and generate by causing partial combustion of the carbonaceous residue and gases entering the zone from below. Still moving downwardly, the charge enters a post-combustion zone at 900-1100 deg.C, air being introduced to sustain combustion and maintain temp. so that on entering the penultimate zone, a reduction zone contg. steam, any zinc oxide present is reduced to zinc metal. The final zone is a cooling zone where aqueous cooling medium is introduced to lower temp. to 350-500 deg.C, the steam generated passing into the reduction zone. The hot aggregate is discharged, the inert material segregated from carbonaceous material and recycled through the column.    USE/ADVANTAGE -   Process is used to recover pyrolysis oils, gases, carbon black, zinc, and other filler materials from waste rubber, partic. scrap car tyres. Process can be operated continuously and is energy efficient, the energy needs being met by combustion of the rubber constituents to a large extent. Thus, the process provides an economical and acceptable environmental means for disposing of scrap tyres yielding valuable by-products