Keywords: thermal plasma pyrolysis, used tyres, old tyres, waste recycling, carbon black, nitrogen plasma reactor, environmental technology, water steam injection, sulphur, waste management, waste disposal
Pyrolysis processing of used old tyres by thermal plasma technology
Thermal plasma pyrolysis of used old tyres was studied in a nitrogen plasma reactor in order to evaluate the material and energy recycling potential. The main gaseous products from thermal plasma pyrolysis of used old tyres were identified by chromatography as H2, CO, CH4, C2H2, C2H4. In the presence of water steam injection into the plasma reactor, the yield of H2 and CO can reach up to 38.3% of the gaseous product, which are valuable syngas components. The solid residue contained 82–85 wt.% elemental carbon, had surface area about 70 m²/g, and could be used as a replacement for semi-reinforcing carbon black. The distribution of sulphur in the pyrolytic products was also investigated. It was found that more than 80% of total sulphur was deposited in the solid residue. Our study indicated that thermal plasma pyrolysis might be a useful way for disposal of tyres waste.