Thermal Treatment

Abstract

The invention provides methods and apparatus for thermal treatment, e.g. for pyrolysis of lignin. The lignin is provided to a reaction chamber as a paste, which can reduce or avoid process difficulties encountered when heating lignin.

1 . A process for the pyrolysis of lignin comprising the steps:
 (a) feeding a paste comprising lignin into a reaction chamber; and   (b) performing pyrolysis on the paste in the reaction chamber.   
     
     
         2 . A process according to  claim 1  wherein the paste is a mixture of lignin with one or more further components. 
     
     
         3 . A process according to  claim 2  wherein the paste is a suspension of lignin in a further component. 
     
     
         4 . A process according to  claim 3  wherein a portion of the lignin is dissolved in the at least one further component and a portion of the lignin is suspended in the further component. 
     
     
         5 . A process according to  claim 2  wherein the mass ratio of lignin to the further component is from 1:5 to 10:1. 
     
     
         6 . A process according to  claim 2  wherein the further component is a polar solvent. 
     
     
         7 . A process according to  claim 6  wherein the further component is an alcohol. 
     
     
         8 . A process according to  claim 7  wherein the further component is methanol. 
     
     
         9 . A process according to  claim 2  wherein the further component is a non-polar compound. 
     
     
         10 . A process according to  claim 2  wherein the process further comprises the step of mixing together lignin and the one or more further components to form the paste. 
     
     
         11 . A process according to  claim 1  wherein the temperature inside the reaction chamber is at least 300° C. when the paste is fed into the chamber. 
     
     
         12 . A process according to  claim 1  wherein the reaction chamber is a fluidised bed reaction chamber, a fixed bed reaction chamber or a heated vessel. 
     
     
         13 . A process according to  claim 1  wherein the paste is fed into the reaction chamber via a feeding assembly, the feeding assembly being provided with a cooling system. 
     
     
         14 . A process according to  claim 13  comprising feeding the paste into the reaction chamber at a position toward or at the base of the reaction chamber. 
     
     
         15 . A process according to  claim 1  wherein agitation is provided to the interior of the reaction chamber during feeding and/or pyrolysis. 
     
     
         16 . Apparatus for the pyrolysis of lignin, comprising:
 a pyrolysis reaction chamber; and   a feeding assembly adapted to supply paste comprising lignin into the reaction chamber.   
     
     
         17 . Apparatus according to  claim 16  further comprising a paste supply. 
     
     
         18 . Apparatus according to  claim 16  wherein the feeding assembly is provided with a cooling system. 
     
     
         19 . Apparatus according to  claim 16  wherein the feeding assembly is arranged to deliver paste to the reaction chamber at a position toward or at the base of the reaction chamber. 
     
     
         20 . Apparatus according to  claim 19  further comprising an agitator arranged to provide agitation in the reaction chamber.