Analysis of comprehensive utilization of waste tire pyrolysis char by combustion method

A technical route for large-scale utilization of waste tire pyrolytic char (TPC) by combustion method was proposed. The physical and chemical characteristics and combustion characteristics of TPC were studied and compared with anthracite, semi-coke, bituminous coal, coal char, coal gasification fly ash which have similar chemical compositions. And the material composition of TPC ash was analyzed. The results show that the overall particle size of TPC particles is larger (average particle size is 193.8 μm), and they are formed by bonding fine carbon black particles. The microstructure of TPC particles is different from that of coal and coal char. TPC has a well-developed pore structure, and its specific surface area and pore volume are close to coal char. TPC is composed of a large amount of amorphous carbon, which has a low degree of graphitization and large spacing of aromatic lamellae. TPC carbon has a highly disordered structure, low cross-linked structure strength, and a looser overall carbon structure. The surface functional groups in TPC mainly exist in the form of aromatic carbon and aliphatic carbon, and only a small amount of O = C-O and Π-Π*. The volatiles content of TPC is only 4.36%, but the ignition temperature of TPC is similar to that of lean coal, and the activation energy of TPC is lower than that of anthracite and lean coal, which is caused by the developed pore structure and loose carbon structure. TPC is a high-quality high-calorific value fuel, replacing coal coke and semi-coke as fuel, thereby reducing fossil energy consumption. The ash of TPC can be processed to obtain Zn and white carbon black (SiO₂) raw material, which has high utilization value. The combustion method of TPC can realize its resource utilization and large-scale application.