Production of pyrolytic carbon from waste of rubber-containing products for use in foundry

Abstract

The paper deals with the processing of rubber‑containing products by pyrolysis in order to obtain pyrolytic carbon, which is of practical interest for the needs of the foundry. It has been established that the process of gas phase evolution during rubber pyrolysis proceeds in the temperature range of 50–550 °C, the maximum release peaks for all detected substances are in the range of 375–500 °C, the total release is over 140 mg per kg of feedstock. It was found that the concentration and temperature of the exhaust gases make it possible to neutralize them in an autocatalytic mode using the principle of filtration combustion. It is shown that the optimal temperature for obtaining a solid carbonaceous residue (target product) is 320–380 °C, an increase in temperature above 500 °C leads to a decrease in the mass fraction of pyrolytic carbon from 64.8 to 31.9 %, respectively, the proportion of exhaust gases increases from 5 to 8 %, and heating oil yield from 30.2 to 60.1 %.