Pyrolysis of locally sourced scrap tyres for the production of char

Abstract

With respect to the environmental problems and health hazards caused by countless scrap tyre piles around Nigerian cities, pyrolysis of scrap tyre was carried out to examine its potential as a viable source of energy. A thermo chemical reactor furnace of 17.4 litres capacity was designed with temperature specification of 1,200^oC at a pressure of 2.3 MN/m². Scrap tyres from light duty vehicles were processed by washing them in water to remove dirt, cut into sample sizes of 20 mm x 30 mm and then weighed in various portions of 1 kg each. 1 kg mass of the processed scrap tyres was pyrolysed in each batch of pyrolysis experiment to obtain char at different pyrolysis temperatures of 250^oC, 350^oC, 450^oC, and 600^oC. Proximate and ultimate analyses of the char resulting from the pyrolysis were carried out. The pyrolysis process produced char with average composition of 83.30% carbon, 5.45% hydrogen, 0.52% nitrogen, 1.17% sulphur and 1.90% oxygen. The analysis of percentage composition of the raw scrap tyre samples gave 79.86% for carbon, 7.35% hydrogen, 0.39% nitrogen, 1.57% for sulphur and 6.50% for oxygen. The 79.86% carbon which is primarily made of char indicated that the adoption of pyrolysis for processing of scrap tires can contribute immensely to the production of char which can further be processed into activated carbon, compressed into charcoal briquettes, used as soil amendment etc.