Process for producing a refinery stream-compatible bio-oil from a lignocellulosic feedstock

Abstract

In one aspect, a method for rendering biomass-derived pyrolysis oil miscible with refinery hydrocarbons comprises mixing a high oxygen content bio-oil having an oxygen content of at least about 10 wt. % with a low oxygen content bio-oil having an oxygen content of less than about 8 wt. % to produce a blended oil. The blended oil may be hydrotreated to produce a deoxygenated hydrotreated mixture from which water is removed using a separator, resulting in a low oxygen content hybrid bio-oil intermediate miscible in refinery process streams. A portion of the low oxygen content hybrid bio-oil intermediate may be recycled with the high oxygen content bio-oil or removed for use in a refinery process stream for further hydroprocessing.

What is claimed is: 
     
         1 . A method for rendering biomass-derived pyrolysis oil miscible with refinery hydrocarbons, the method comprising the steps of:
 a) mixing (i) a high oxygen content bio-oil comprising an oxygen content of at least about 10 wt. % with (ii) a low oxygen content bio-oil an oxygen content of less than about 8 wt. % to yield a blended oil.   
     
     
         2 . The method of  claim 1 , further comprising:
 b) hydrotreating the blended oil to yield a hydrotreated mixture comprising (i) low oxygen-content hydrotreated bio-oil and (ii) water, wherein the low oxygen-content hydrotreated bio-oil has an oxygen content of 10 wt. % or less.   
     
     
         3 . The method of  claim 2 , further comprising:
 c) removing water from the hydrotreated mixture to yield a low oxygen content hybrid bio-oil intermediate, wherein water removal is effected via a phase separation between the low oxygen content hydrotreated bio-oil and the water.   
     
     
         4 . The method of  claim 3 , further comprising:
 d) combining at least a portion of the low oxygen content hybrid bio-oil intermediate with the high oxygen content bio-oil in step (a), and   e) repeating steps (a) through (d).   
     
     
         5 . The method of  claim 1 , wherein the high oxygen content bio-oil is produced in a conversion reactor by a conversion process selected from the group consisting of fast pyrolysis, slow pyrolysis, liquefaction, gasification, or enzymatic conversion. 
     
     
         6 . The method of  claim 1 , wherein the high oxygen content bio-oil comprises an oxygen content between about 25 wt. % and 50 wt. %. 
     
     
         7 . The method of  claim 1 , wherein the low oxygen content bio-oil comprises a biomass feedstock produced by pyrolysis or catalytic pyrolysis, hydroliquefaction via catalytic hydrogenation, or by hydrogen donor solvent liquefaction. 
     
     
         8 . The method of  claim 1 , wherein the low oxygen content bio-oil is produced from a hydrotreated lignocellulosic feedstock. 
     
     
         9 . The method of  claim 1 , wherein the low oxygen content bio-oil comprises an oxygen content up to about 8 wt. %. 
     
     
         10 . The method of  claim 1 , wherein the low oxygen content bio-oil has a total acid number less than about 10 mg KOH/g. 
     
     
         11 . The method of  claim 1 , wherein upon mixing in the first mixing unit, the ratio of the high oxygen content bio-oil to the low oxygen content bio-oil in the blended oil is between about 0.1 and about 0.3. 
     
     
         12 . The method of  claim 1 , wherein the high oxygen content bio-oil and the low oxygen content bio-oil are mixed so that the blended oil has a total acid number between about 50-100 mg KOH/g. 
     
     
         13 . The method of  claim 4 , wherein the wherein the low oxygen content hybrid bio-oil intermediate is substantially miscible in a non-polar solvent. 
     
     
         14 . The method of  claim 4 , wherein the low oxygen content hybrid bio-oil intermediate has a total acid number less than or equal to 20 mg KOH/g. 
     
     
         15 . The method of  claim 4 , wherein the low oxygen content hybrid bio-oil intermediate has an average molecular weight between about 200-300 g/mol and a boiling point range below 500° C. 
     
     
         16 . The method of  claim 4 , wherein the wherein the low oxygen content hybrid bio-oil intermediate is added to a second low oxygen content bio-oil in a second mixing unit to yield a second blended oil, wherein the second blended oil is added to the high oxygen content bio-oil in the first mixing unit. 
     
     
         17 . A system for producing a bio-oil comprising:
 a biomass conversion unit facilitating production of a high oxygen content bio-oil from a biomass feedstock;   a first mixing unit comprising a first inlet receiving the high oxygen content bio-oil from the conversion unit and a second inlet receiving a low oxygen content bio-oil from a bio-oil feedstock to form a blended oil;   a hydrotreater comprising an inlet receiving the blended oil from the first mixing unit to produce a hydrotreated bio-oil mixture;   a separator for separating water from the hydrotreated bio-oil mixture to produce a low oxygen content hybrid bio-oil intermediate, the separator comprising a first inlet receiving the hydrotreated bio-oil mixture from the hydrotreater, an outlet supplying the low oxygen content hybrid bio-oil intermediate to the first mixing unit, and optionally an outlet supplying the low oxygen content hybrid bio-oil intermediate to a source of refinery hydrocarbons.   
     
     
         18 . The system of  claim 17 , further comprising a second mixing unit, wherein the second mixing unit comprises a first inlet receiving the low oxygen content hybrid bio-oil intermediate from the separator, a second inlet receiving a low oxygen content bio-oil from a bio-oil feedstock to produce a low oxygen blended oil, and an outlet supplying the low oxygen blended oil formed in the second mixing unit to the first mixing unit; and wherein the separator further comprises an outlet supplying the low oxygen content hybrid bio-oil intermediate to the second mixing unit. 
     
     
         19 . The system of  claim 17 , wherein the biomass conversion unit comprises a pyrolyis unit for forming a high oxygen content pyrolyis oil. 
     
     
         20 . A blended oil composition, comprising a high oxygen content bio-oil with an oxygen content of at least about 10 wt. % bio-oil blended with a low oxygen content bio-oil with an oxygen content of less than about 8 wt. %.