Generating deoxygenated pyrolysis vapors

Abstract

The present disclosure relates generally to novel biomass pyrolysis processes and systems that decrease entrainment of char and other contaminants with the pyrolysis vapors. In certain embodiments, the present disclosure provides methods and systems to prevent entrainment of particles of char and heat carrier with pyrolysis vapors leaving a reactor, while allowing rapid upgrading of the vapors by catalyst(s) that are held in a an upgrading reactor and protected from contact with the char.

We claim: 
     
         1 . A process for the production and upgrading of a pyrolysis product, comprising the steps of:
 (a) pyrolyzing a biomass feedstock in a first reactor comprising at least one auger that conveys the feedstock through the reactor from a first end towards a second end, wherein said pyrolyzing forms primary pyrolysis products comprising a primary gaseous product and char;   (b) passing the primary gaseous product through a first outlet at or near the top of the first reactor and to a second reactor, wherein the primary gaseous product passing through the first outlet entrains less than 0.5 wt. % of the char produced by the pyrolyzing of step (a);   (c) contacting the primary gaseous product with an upgrading catalyst;   (d) removing the char from the first reactor via a second outlet located at or near the bottom of the first reactor.   
     
     
         2 . The process of  claim 1 , wherein the primary gaseous product passes upward through a disengagement zone prior to leaving the first reactor via the first outlet, wherein the terminal falling velocity of entrained char and heat carrier particles becomes greater than the upward local velocity of the primary gaseous product in the disengagement zone, thereby causing at least 99.5 wt. % of the char and heat carrier particles to be retained in the first reactor. 
     
     
         3 . The process of  claim 1 , wherein the first outlet is located closer to the second end of the first reactor relative to the second outlet, thereby decreasing entrainment of char in the primary gaseous product. 
     
     
         4 . The process of  claim 1 , wherein the first outlet is located closer to the first end of the first reactor relative to the second outlet, thereby decreasing entrainment of char in the primary gaseous product. 
     
     
         5 . A system for the production and upgrading of a pyrolysis product, comprising a pyrolysis reactor adapted for pyrolyzing a biomass feedstock to produce a primary gaseous product, wherein the pyrolysis reactor comprises at least one auger, an inlet for a biomass feedstock and an outlet, wherein the pyrolysis reactor contains a solid particulate heat carrier and char, wherein the reactor is adapted to provide a disengagement zone that is, in turn, adapted to allow the terminal falling velocity of entrained char and heat carrier particles to become greater than the upward local velocity of the primary gaseous product in the disengagement zone prior to leaving the first reactor via the outlet such that the reactor retains at least 99.5 wt. % of the solid particulate heat carrier and char in the pyrolysis reactor.