Abstract: A method for thermally decomposing a carbonaceous waste material including: filling a reactor defined by a reactor wall with the waste material and an auxiliary material, resulting in a reactor content, the auxiliary material including abrasive particles; heating the reactor contents in the absence of oxygen, such that gaseous products are formed by pyrolysis of the waste material and the abrasive particles do not melt or thermally decompose; moving the reactor contents during the pyrolysis, the moving being adapted to mix the reactor contents and to cause the abrasive particles to scrape over at least parts of the reactor wall. The auxiliary material has a composition to include a component adapted to bind halogens present in the gaseous products and/or so that the brittleness of the auxiliary material is greater than the brittleness of the reactor wall.

Abstract: A method for pyrolysis of a mass of waste material, includes: providing a screw arrangement adapted to supply heat to the mass by mechanical shear; providing a reactor after the screw arrangement, adapted to supply heat to the mass in the absence of oxygen by heating the reactor wall; heating the mass to an exit temperature and increasing the pressure to an exit pressure in the screw arrangement; thermally degrading the mass in the reactor. The mass is brought into an extreme condition at the exit temperature and exit pressure by the screw arrangement, such that during the pressure drop pyrolysis occurs, thereby forming gaseous hydrocarbons within the connecting element.