Process for pyrolysis of substantially plastics material of inconstant composition

Abstract

This invention relates to the processing of plastics materials for re-use and valorisation in chemical recycling processes for the re-use of substantially plastics materials otherwise destined for disposal. In particular the invention relates to a process for the pyrolysis of substantially plastics material to obtain at least liquid hydrocarbons that are in the liquid state at 25°C comprising the following steps: a) feeding the substantially plastics material optionally already in the molten and / or preheated state to a pyrolysis reactor; b) bringing said material in said pyrolysis reactor to a temperature of between 330°C and 580°C in the substantial absence of oxygen and at a pressure of between atmospheric pressure and 13 bar(a); c) holding said material in said pyrolysis reactor at a temperature of between 330°C and 580°C for a time sufficient to produce at least one effluent in the gaseous state in said pyrolysis reactor; d) adjusting the pressure in said pyrolysis reactor in relation to characteristic parameters defined by the composition of said substantially plastics material and / or characteristic parameters defined by the products of said pyrolysis process, while maintaining said pressure at a value of between atmospheric pressure and 13 bar(a); e) partly or totally condensing said effluent in the gaseous state so as to form at least one fluid comprising liquid hydrocarbons that are in the liquid state at 25°C which quantitatively is at least 10% by mass with respect to the mass of substantially plastics material fed; f) the process being characterized by the fact that the pressure adjustment of step d) has low latency.