Thermogravimetric analysis of co-pyrolysis of coal and waste and used tires

Waste tires can be used as a substitute for coal due to the high calorific value. In this study, the co-pyrolysis characteristics of the waste tires (truck tires, liners and nylon tires), pulverized coal and their blends are studied using thermogravimetric analyzer. The pyrolysis of truck tires, liners and coal is characterized by a three stages reaction while the pyrolysis of nylon tires and their blends are four stages. The pyrolysis characteristics of the blends can be expressed by the superposition of the pyrolysis characteristics of the one-component material, indicating the slight interaction of the co-pyrolysis between the waste tire and the coal. The co-pyrolysis kinetics of waste tires, coal and their blends are also investigated. For the blends of coal with truck tires and liners, the increased content of coal reduces the activation energy in the 2nd stage and leads to an increase and then a decrease in the 3rd stage. Different from the former, the activation energy increases with the increase of tire powder in both the 2nd and 3rd stages in the blends of coal and nylon tires. This is attributed to the fact that the nylon tires contain more synthetic rubber than truck tires and liners.