Method for producing methane from biomass

摘要

A multi-stage method and apparatus for producing methane from biomass in which the biomass is hydropyrolyzed in a reactor vessel containing molecular hydrogen and a deoxygenating catalyst, the output of which is hydrogenated using a hydroconversion catalyst. The output from the hydroconversion step is provided to a water-gas-shift process providing a mixture of H2O and product gases including CO2, H2, and methane. The mixture components are separated, resulting in a product stream comprising substantially only methane.

主权项

1. A method for producing methane from biomass comprising the steps of:
a) hydropyrolyzing biomass in a hydropyrolysis reactor vessel containing molecular hydrogen and a deoxygenating catalyst, producing a hydropyrolysis product comprising char and vapors; b) separating said char from said hydropyrolysis product, producing a reduced char hydropyrolysis product; c) hydroconverting said reduced char hydropyrolysis product in a hydroconversion reactor vessel using a hydroconversion catalyst, producing a hydroconversion product; d) separating from said hydroconversion product condensed liquid water and a gaseous mixture comprising CO2, H2, and methane, wherein said gaseous mixture is free from char; and e) introducing at least a first portion of said gaseous mixture as a feed to a steam reformer, producing reformer CO2 and reformer H2, and f) introducing at least a second portion of said gaseous mixture to a methanation reactor, forming additional methane,
wherein both hydropyrolyzing step a) and hydroconverting step c) are exothermic.