Methods for energy-efficient high solids liquefaction of biomass

Patent metadata

Field	Value
Publication number	US-2016289780-A1
Application number	US-201615090898-A
Country	US
Kind code	A1
Filing date	Apr 5, 2016
Priority date	Oct 9, 2013
Publication date	Oct 6, 2016
Grant date	—

Abstract

The present disclosure is generally related a method for the liquefaction of high-solids biomass substrates. Particularly, biomass can be added to a reactor until a pressure drop, measured inline, reaches the maximum system limitations. A commercial enzyme mixture (specific for the particular type of biomass to be processed) may then be added to the biomass, forming a slurry. The pressure may be continuously monitored and when the pressure drop reaches a steady state (which can be determined by little or no change in pressure drop for several minutes), more biomass may then be added until the high pressure limit of the pump system is reached again. The method can be repeated until the desired quantity of biomass is processed.

First claim

What is claimed is:

1 . A method of processing biomass, the method comprising:
mixing a first batch of biomass and an enzyme to form a first slurry with a first viscosity; adding a second batch of biomass to the first slurry to form a second slurry with a second viscosity; and adding enzyme to the second slurry to form a third slurry with about the first viscosity.

2 . A method of processing biomass, the method comprising:
(a) providing a reactor with components configured in a flow loop, the components comprising:
a tank with a mixer;
(ii) a pump to move material through the flow loop; and
(iii) a pressure transducer to measure a pressure drop within a pipe that connects the components to form the flow loop, wherein the flowing material flows within the pipe;
(b) loading a first batch of biomass into the tank, monitoring a measured pressure drop within the pipe between a first point along the pipe and a second point along the pipe as the biomass is loaded into the tank, and ceasing the loading when the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe is at a maximum based on the flow loop's limitations; (c) adding an enzyme to the tank and using the mixing the enzyme with the biomass to form a first slurry; (d) monitoring the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe as the slurry is formed; (e) when the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe reaches a quasi steady state after a decrease in the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe, adding an additional batch of biomass into the tank until the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe is at the maximum based on the flow loop's limitations; (f) adding additional enzyme to the tank and mixing the enzyme with the biomass to form a second slurry; (g) wherein pH of each slurry is maintained at an approximately constant value by adding a buffer or by adding at least one of an acid and a base to each slurry; and (h) repeating steps (e) through (g) until a desired quantity of biomass is processed.

3 . The method of claim 2 , wherein the reactor further comprises:
an MRI rheometer configured within the flow loop for obtaining velocity profiles of the slurries; wherein the method further comprises:
obtaining velocity profiles of the slurries while in the pipe using the MRI rheometer;
constructing a rheogram from the velocity profiles and from the pressure drop measured within the pipe between the first point along the pipe and the second point along the pipe as the slurries are formed;
calculating a yield stress value from the rheogram; and
using the calculated yield stress value to determine when to add additional enzyme to the tank.

4 . The method of claim 3 , wherein the velocity profiles of the slurries are obtained every 1 to 2 minutes.

5 . The method of claim 2 , wherein the first and second slurries have a solids concentration of at least 15% w/w.

6 . The method of claim 2 :
wherein the reactor further comprises a heat exchanger configured within the flow loop for heating the slurries; and wherein the method further comprises heating the slurries to a temperature of between about 45° C. and 65° C.

7 . The method of claim 2 , wherein the biomass comprises cellulosic material and wherein the enzyme comprises endo-cellulase.

8 . A method of processing biomass, the method comprising:
(a) providing a reactor with components configured in a flow loop, the components comprising:
a tank with a mixer;
(ii) a pump to move material through the flow loop; and
(iii) a pressure transducer to measure a pressure drop within a pipe that connects the components to form the flow loop and wherein the material flows within the pipe;
(iv) a MRI rheometer;
(b) loading a first batch of biomass and buffer into the tank, monitoring a measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe as the biomass is loaded into the tank, and ceasing the loading when the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe is at a maximum based on the flow loop's limitations; (c) adding an enzyme to the tank and mixing the enzyme with the biomass to form a first slurry; (d) monitoring the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe as the slurry is formed; (e) when the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe reaches a quasi steady state after a decrease in the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe, adding an additional batch of biomass into the tank until the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe is at the maximum based on the flow system's limitations; (f) obtaining velocity profiles of the slurries while in the pipe using the MRI rheometer; (g) constructing a rheogram from the velocity profiles and from the pressure drop measured within the pipe between the first point along the pipe and the second point along the pipe as the slurries are formed; (h) calculating a yield stress value from the rheogram; using the calculated yield stress value to determine when to add additional enzyme to the tank; (j) adding additional enzyme to the tank and mixing the enzyme with the biomass to form a second slurry; (k) wherein pH of each slurry is maintained at a constant value by adding a buffer or by adding at least one of a base and an acid to each slurry; and (I) repeating steps (d) through (k) until a desired quantity of biomass is processed.

9 . The method of claim 8 , wherein the velocity profiles of the slurries are obtained every 1 to 2 minutes.

10 . The method of claim 8 , wherein the first and second slurries have a solids concentration of at least 15% w/w.

11 . The method of claim 8 :
wherein the reactor further comprises a heat exchanger configured within the flow loop for heating the slurries; and wherein the method further comprises heating the slurries to a temperature of between about 45° C. and 65° C.

12 . The method of claim 8 , wherein the biomass comprises cellulosic material and wherein the enzyme comprises endo-cellulase.

13 . A method of processing biomass in a reactor with components configured in a flow loop, the components comprising: a tank with a mixer, a pump to move material through the flow loop and a pressure transducer to measure a pressure drop within a pipe between a first point along the pipe and a second point along the pipe, the pipe connecting the components to form the flow loop, wherein the material flows within the pipe, the method comprising:
(a) loading a first batch of biomass into the tank, monitoring a measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe as the biomass is loaded into the tank, and ceasing the loading when the measured pressure drop within the pipe between the first point along the pipe and the second point along the pipe is at a maximum based on the flow loop's limitations; (b) adding an enzyme to the tank and mixing the enzyme with the biomass to form a first slurry; (c) monitoring the measu

Assignees

• Univ California
• Aspect Ai Ltd

Inventors

• Cardona Maria
• Powell Iii Robert Louis
• Mccarthy Michael John
• Zicari Tina Jeoh
• Tozzi Emilio Javier

Classifications

• G01N11/04

  through a restricted passage, e.g. tube, aperture · CPC title

• G01N24/088

  Assessment or manipulation of a chemical or biochemical reaction, e.g. verification whether a chemical reaction occurred or whether a ligand binds to a receptor in drug screening or assessing reaction kinetics · CPC title

• C12Q3/00 Primary

  Condition responsive control processes (apparatus therefor C12M1/36; controlling or regulating in general G05) · CPC title

• C12P2201/00

  Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis · CPC title

• G01N24/085 Primary

  Analysis of materials for the purpose of controlling industrial production systems · CPC title