System and Process for the Desulphurization of Tyre Pyrolysis Feedstocks

The process consists of two continuous stages carried out under inert, vacuum conditions.

In the first stage, cold feedstock is fed into a preheating vacuum oven for ex-situ desulphurization. It is heated to a controlled temperature for a set time to break sulphur–sulphur and sulphur–carbon bonds without significantly affecting carbon–carbon bonds. This releases sulphur as hydrogen sulphide (H₂S), which is removed before the next stage to prevent unwanted reactions.

In the second stage, the desulphurised feedstock is transferred to a second vacuum oven for pyrolysis at a higher temperature. Solid char is removed, while pyrolysis vapours pass through a multi-stage fractional condensation system. Vapours are cooled stepwise to separate oil fractions based on boiling points, with condensed oils draining by gravity and cooling under ambient conditions to limit cracking. Adjusting condenser temperatures or stages allows control over the fuel properties of the resulting pyrolysis oils.