Disposal methods for used passenger car tires: One of the fastest growing solid wastes in China

With the rapid growth in the number of passenger cars (PCs) in China over the past decades, more than ten million tons of used tires have already become solid wastes and subsequently caused serious environmental issues. Due to the presence of synthetic rubber in PC tires, waste PC tires cannot be disposed through rubber reclaiming technology. Thus, waste PC tires have become one of fastest growing solid wastes in China. First, the current disposal capacity of the pyrolysis method, regarded as a promising technology for the disposal of waste PC tires, is surveyed and compared with other disposal methods mentioned in previous papers. Second, this work establishes a model to predict the total number of waste PC tires in the next five years depending on the rate of PC growth and current waste tire disposal capacity. Moreover, pyrolysis is evaluated on 15 collected waste PC tires selected from the most representative tire brands in the Chinese market. The corresponding results imply that similar to 68.5% of S was into oil and similar to 44.3% N and large amount of heavy metals resided in solid carbon which severely limit further applications. Finally, a new pyrolysis technology is introduced that may represent a solution to the limits in the application of tire disposal methods and relief for the coming waste tire crisis. (c) 2021 Institute of Process Engineering, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.

Automated summary

With the rapid growth of passenger cars in China, waste passenger car tires have become one of the fastest growing solid wastes. This study investigates the current disposal capacity of the pyrolysis method for waste passenger car tires and predicts the future total number of waste tires based on car growth rate and disposal capacity. Additionally, an evaluation of pyrolysis on 15 collected waste tires was conducted, revealing the limitations and the potential of a new pyrolysis technology.