More than 1 mln. tons tyres are discharged annually in Russia. The largest part of them – 60 % is stored, 10-30 % is burned and only 10-30 % of the tyres are subject to utilization.

Worn tyres are known as an environmental contamination source. Firstly, they cannot be biologically decomposed, secondly, they are inflammable, whereas not easily, although once ignited, it is difficult to extinguish. Thirdly, while storing, the tyres accumulate water, which encourages breeding of blood-sucking insects, transmitters of infectious diseases. However, waste tyres can be viewed as a valuable source of secondary raw materials: rubber (caoutchouc), soot (in fact pure carbon) and metal cord since 90% of all rubber-containing waste is produced from tyres.

The present investigation was carried out to develop the process of auto tyres utilization. The choice of the process for utilization was based on summarizing the data on the existing technologies: pyrolisis, burning, crushing, thermal solvolysis, using the energy of high frequencies to process the worn tyres.

After studying the problem we focused on the technology based on thermal destruction of secondary rubber material (tyre-cover) in carbon background under higher pressure and using energetic effects, specifically, super-high-frequency (SHF) radiation.

Practically the process of devulcanisation in the conditions of super-high-frequency is of more interest compared to other utilization methods of polymer materials since it can be carried out in more comfortable conditions, which increases the output of liquid products, reduces the output of gases and minimizes toxic emissions. Besides, solution of polymer in dissolvents under the SHF conditions enables to process a large fraction of tyre rubber. Nevertheless despite of these advantages compared to other utilization technologies we could hardly find data on the use of SHF.

The objects of the investigation were: oil from a deposit in Yakutia, auto tyres and disposed motor oils of a transportation enterprise.

At original equipment using the source of SHF radiation the process of decomposition of worn truck tyre-covers in oil and motor oil was investigated. It resulted into output of the following products (Table).

Table

Distillation of the suspense of the soluted rubber enables to develop products for further processing.