The effect of the secondary reactions on volatile composition during the pyrolysis treatment of scrap tires

ABSTRACT

The phenomenon of the secondary reactions of volatiles prevails during the pyrolysis process of scrap tires, but less is known about the influence of volatiles’ residence time and temperature on the pyrolytic oil compositions. Experiments on the secondary reactions caused by residence time and temperature of volatiles were carried out on a lab-scale fixed bed reactor. The regularity of the secondary reactions was presented in detail according to the distribution of liquid and gaseous pyrolytic products. Considering the inadequacy of lab-to-industry research, experiments were further carried out on a pilot-scale auger reactor. The results of the pilot-scale system were corresponding well to the regularity obtained in lab-scale experiment, demonstrating the universality of the regularity in this work. At in situ pyrolysis condition without any secondary reactions, limonene content reached up to 46.24% while a high yield of BTEX (50.55%) was obtained at 700℃/60 s. A remarkable increase of methane and ethane was observed at 700℃/60 s, reaching 0.058 and 0.040 g·(g scrap tire)⁻¹, respectively. This paper provided a novel strategy to selectively produce target products in a simple and economical method. The results were of great significance for guiding the optimisation of pyrolysis parameters in industrial equipment to obtain desired valuable products.

GRAPHICAL ABSTRACT

KEYWORDS:

• Scrap tire
• volatiles’ residence time
• secondary reactions
• products valorisation
• industrial application

Acknowledgments

This work was supported by the Key Research and Development Programme of Zhejiang province (2020C03084) and Key Research and Development Programme of Shandong province (2019JZZY020806).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article [and/or] its supplementary material.

Additional information

Funding

This work was supported by Key Research and Development Programme of Zhejiang province: [grant number 2020C03084]; Key Research and Development Programme of Shandong province: [2019JZZY020806].