The microwave assisted pyrolysis process is carried out inside a reactor consisting of two chambers: tyres to be treated are placed in the loading and safety chamber, followed by the pyrolysis chamber in which the process takes place. Hydrocarbon vapours that develop during the process are condensed and collected by a condensing system, while uncondensable gases can be fired or used for cogeneration. After the process, the solid materials, carbon black and steel, are transferred from the pyrolysis chamber to the cooling chamber and through a post-treatment it is possible to obtain the separation of the different materials.
Technology
The application of microwaves to pyrolysis allows to overcome the critical issues typical of classic pyrolytic processes such as transients of switching on and off that cause unsustainable stoppage of machine. Acting directly on the material to be treated, microwaves allow a uniform heat transfer which ensures a homogeneous distribution of temperatures inside the reactor. This results in a different heating rate and a different vapours residence time in the reactor compared to classical pyrolysis, allowing a better profile of the chemical composition of the pyrolysis products.
This technology consequently ensures an easier management both in terms of process and machine structure.
Outline
Inlet chamber | Pyrolysis chamber | 1st Cooling chamber | 2nd Cooling chamber
Inlet chamber
The material, once introduced, is preheated with the aid of thermal resistances in order to reach an optimal temperature for entering the pyrolysis chamber.
Pyrolisis chamber
Using microwaves the thermochemical decomposition of the polymer matrix is induced. In this way the solid, liquid and gaseous fractions are produced from a tyre.
1st Cooling chamber
The material is subjected to a first cooling cycle in the shade of the pyrolysis process in order to radically lower the temperature of the material.
2nd Cooling chamber
The material is subjected to a second cooling cycle in the shade of the pyrolysis process up to the extraction temperature.