Method and installation for thermochemical conversion of raw material containing organic compounds

Abstract

The invention relates to the field of organic substance processing, in particular to the method for processing the shredded wood waste, plant industry products, food industry waste, livestock and poultry waste. Products obtained during the thermal processing of organo-containing raw materials can be used as a fuel. The method comprises drying, hermetic supply of raw materials to the pyrolysis reactor, thermal decomposition of raw materials without air access in the pyrolysis reactor to produce solid products and vapour-gas mixture, the subsequent separation of it by condensation into liquid products and gaseous products. After drying, the organo-containing raw material before supply into the pyrolysis reactor is preheated to a temperature close to, but not exceeding the initiation temperature of thermal decomposition of the least thermally stable component of organo-containing materials Surfaces of the chamber are heated to a temperature which excludes the condensation of pyrolysis vapour-gas products, and raw material heating temperature is controlled by duration of stay in the preheating zone; Thermal decomposition is implemented in the form of the following successive stages occurring in corresponding zones of the pyrolysis reactor, having the possibility of independent temperature control: primary pyrolysis zone, vapour-gas mixture purification zone, secondary pyrolysis zone The installation for thermochemical conversion of organo-containing raw materials comprises a drying chamber, a hermetic raw material supply chamber, a pyrolysis reactor, a device for independent and elastic setting of the inclination angle of blades, a condensation unit. The pyrolysis reactor have a surface rotating with at least one blade and a rotation axis coinciding with the longitudinal axis of the pyrolysis reactor, and at least one ablation surface of circular or elliptical section, perpendicular to the rotation axis of the rotating surface. The hermetic raw material supply chamber is equipped with raw material heating means. The pyrolysis reactor workspace is divided along the path of raw materials into the following successive zones equipped with independent heating devices—a primary pyrolysis zone, a vapour-gas cleaning zone, equipped with a device for separation and return of incomplete destruction products, and a secondary pyrolysis zone. The use of the claimed group of inventions allows increasing the efficiency of the process of thermochemical conversion of organo-containing raw materials.

1 . A method for thermochemical conversion of an organo-containing raw material, comprising: drying of said raw material, hermetic supply of said raw material into a pyrolysis reactor, thermal decomposition of said raw material without air access in the pyrolysis reactor to produce solid products and a vapour-gas mixture, subsequent separation of said vapour-gas mixture by condensation into liquid products (a condensed part of the vapour-gas mixture) and gaseous products (an uncondensed part of the vapour-gas mixture), wherein
 (i) after drying and before supply into the pyrolysis reactor, the organo-containing raw material is preheated to a temperature close to, but not exceeding a thermal decomposition initiation temperature of the least thermally stable component of said organo-containing raw material;   (ii) surfaces of a chamber of the pyrolysis reactor are heated to a temperature which excludes condensation of the vapour-gas mixture, and a heating temperature of the raw material is controlled by duration of stay in a preheating zone;   (iii) the thermal decomposition is implemented in a form of the following successive stages occurring in corresponding zones of the pyrolysis reactor, said zones are configured to have an independent temperature control:   a primary pyrolysis, where the raw material is converted into solid products and the vapour-gas mixture;   a purification of the vapour-gas mixture, wherein after the primary pyrolysis the vapour-gas mixture is cooled to a temperature, under which a condensate is formed from a part of the vapour-gas mixture, the formed condensate is returned and mixed with the solid products and unreacted parts of the raw material;   and a secondary pyrolysis, wherein the formed gaseous products together with the primary pyrolysis vapour-gas mixture are returned to the purification stage, and solid products are withdrawn from the secondary pyrolysis zone, preventing their contact with the primary pyrolysis vapour-gas mixture.   
     
     
         2 . The method according to  claim 1 , wherein the condensation is implemented in three successive stages: primary cooling of the vapour-gas mixture in the vapour-gas mixture purification zone of the pyrolysis reactor; condensation of a vapour phase in a condenser; separation of an uncondensed part of the vapour-gas mixture from a dripping liquid with recirculation of a part of the gaseous product through a pyrolysis reactor cleaning zone. 
     
     
         3 . The method according to  claim 1 , wherein the primary pyrolysis is implemented in the mode of a mechanical ablation. 
     
     
         4 . The method according to  claim 1 , wherein zones of primary and secondary pyrolysis are configured to provide an independent purging of the raw material with an inert gas or a gas having reducing or oxidizing properties, said gases are heated to a required temperature. 
     
     
         5 . An installation for thermochemical conversion of organo-containing raw materials, comprising a drying chamber, a hermetic raw material supply chamber, a pyrolysis reactor having a surface rotating with at least one blade and a rotation axis coinciding with the longitudinal axis of the pyrolysis reactor, and at least one ablation surface of circular or elliptical section, perpendicular to the rotation axis of the rotating surface, a device of independent and elastic setting of the inclination angle of blades, a condensation unit consisting of a mass transfer apparatus and a separator, wherein the hermetic raw material supply chamber is equipped with raw material heating means, and the pyrolysis reactor workspace is divided along the path of raw materials into the following successive zones equipped with independent heating devices—a primary pyrolysis zone, a vapour-gas cleaning zone, equipped with a device for separation and return of incomplete destruction products, and a secondary pyrolysis zone. 
     
     
         6 . The installation according to  claim 5 , wherein blades are hinged on the rotating surface of the pyrolysis reactor and have at least one degree of freedom. 
     
     
         7 . The installation according to  claim 5 , wherein the device for independent and elastic setting of the inclination angle of blades has a kinematic connection with them, is removed from the high temperature zone, is isolated from the impact of the vapour-gas mixture being formed and is capable of providing elastic pressure with required periodicity and force in the direction towards both the ablation surface and the rotating surface. 
     
     
         8 . The installation according to  claim 5 , wherein the elasticity in the device for independent and elastic setting of the inclination angle of blades is achieved by pneumatic, mechanical, electromagnetic and other methods. 
     
     
         9 . The installation according to  claim 5 , wherein blades are placed on the rotating surface of the pyrolysis reactor with offset from each other along the length and radius of the rotating surface, in particular, along the helical line. 
     
     
         10 . The installation according to  claim 5 , wherein geometry of the ablation surface of the pyrolysis reactor is made in the form of a helical surface with variable or constant pitch, wherein the helical surface can be made without gaps or by individual sections. 
     
     
         11 . The installation according to  claim 5 , wherein heating devices of each of the three zones of the pyrolysis reactor have the possibility of independent temperature control. 
     
     
         12 . The installation according to  claim 5 , wherein the condensation unit separator is connected by pipeline to the reactor cleaning zone.