Systems and methods for enhancing microbial conversion of biomass using mechanical augmentation

Patent metadata

Field	Value
Publication number	US-2016168596-A1
Application number	US-201514968765-A
Country	US
Kind code	A1
Filing date	Dec 14, 2015
Priority date	Jun 14, 2013
Publication date	Jun 16, 2016
Grant date	—

Abstract

A system and method for converting biomass with no chemical pretreatment is disclosed. Combination of a microbial system and the use of mechanical disruption during fermentation may help achieve high conversion rate without the extra cost and undesirable by-products typically associated with the pretreatment process.

First claim

What is claimed is:

1 . A system for converting biomass into ethanol or other desired products, said system comprising
a) biomass comprising lignocellulosic particles, wherein said biomass has not been pretreated with chemicals, b) a reactor for holding said biomass, c) a microorganism capable of fermenting said biomass to ethanol or desired products, and d) means for mechanically disrupting said lignocellulosic particles, wherein said system is configured such that said biomass is simultaneously subject to both mechanical disruption by said disrupting means and fermentation by said microorganism for a substantial period of time.

2 . The system of claim 1 , wherein said system is configured such that said biomass is subject to mechanical disruption after said biomass is at least partially solubilized.

3 . The system of claim 1 , wherein no reinoculation of said microorganism is required after said biomass is subject to mechanical disruption.

4 . The system of claim 1 , wherein said biomass is heat sterilized before being loaded into said reactor.

5 . The system of claim 1 , wherein said biomass is not heat sterilized before being loaded into said reactor.

6 . The system of claim 1 , wherein said system does not utilize yeast or purified cellulase.

7 . The system of claim 1 , wherein said means for mechanical disruption comprises means selected from the group consisting of metal balls, metal beads, glass balls, glass beads, knife mill, disc mill, roller mill, hammer mill, a device allowing said biomass to flow through an orifice, a cyclone containing milling media with disruption carried out in the fermentor, and combination thereof.

8 . The system of claim 1 , comprising a fermentor, a disrupting device external to the fermentor, and means for withdrawing particle-containing slurry from the fermentor, wherein the slurry is subject to mechanical disruption in said device and is returned either to the same fermentor from which said slurry is withdrawn or returned to a different fermentor.

9 . The system of claim 1 , further comprising means for using pressure developed in said reactor to power said means for mechanical disruption.

10 . The system of claim 1 , wherein said reactor is a closed reactor.

11 . The system of claim 1 , wherein said microorganism is at least one member selected from the group consisting of Clostridium thermocellum, Clostridium claraflavum, Clostridium cellulolyticum, Caldicellusiruptor bescii, Thermoanaerobacterium saccharolyticum, Thermoanaerobacterium thermosaccharolyticum and combination thereof.

12 . A method for converting biomass into ethanol or other desired products, said method comprising
a) adding said biomass comprising lignocellulosic particles and at least one microorganism to a reactor, said at least one microorganism being capable of fermenting said biomass, b) mechanically disrupting said lignocellulosic particles of said biomass after said biomass is partially solubilized, and c) fermenting said biomass with said microorganism to produce ethanol or other desired products.

13 . The method of claim 12 , where in no reinoculation of said at least one microorganism is performed.

14 . The method of claim 12 , wherein said steps (b) and (c) are performed simultaneously.

15 . The method of claim 12 , wherein said lignocellulosic particles of said biomass are disrupted by means selected from the group consisting of metal balls, metal beads, glass balls, glass beads, knife mill, disc mill, roller mill, hammer mill, a device allowing said biomass to flow through an orifice, a cyclone containing milling media with disruption carried out in the fermentor, and combination thereof.

16 . The method of claim 12 , wherein the reactor comprises a fermentor, and a disrupting device external to the fermentor, the method comprising a step of withdrawing lignocellulosic particle-containing slurry from the fermentor, wherein the slurry is subject to mechanical disruption in said device external to the fermentor and is returned either to the same fermentor from which said slurry is withdrawn or returned to a different fermentor.

17 . The method of claim 12 , wherein said mechanical disruption in step (b) is powered by energy harvested from said reactor.

18 . The method of claim 12 , wherein said reactor is a closed reactor.

19 . The method of claim 12 , wherein more than 60% of sugar in said biomass is solubilized after 5-day with incubation with intermittent mechanical disruption.

20 . The method of claim 12 , wherein said microorganism is at least one member selected from the group consisting of Clostridium thermocellum, Clostridium claraflavum, Clostridium cellulolyticum, Caldicellusiruptor bescii, Thermoanaerobacterium saccharolyticum, Thermoanaerobacterium thermosaccharolyticum and combination thereof.

21 . The method of claim 12 , wherein the method does not utilize yeast or purified cellulase.

Assignees

• Dartmouth College

Inventors

• Lynd Lee R
• Paye Julie M D
• Balch Michael

Classifications

• C12P7/10 Primary

  substrate containing cellulosic material · CPC title

• C12P2203/00

  Fermentation products obtained from optionally pretreated or hydrolyzed cellulosic or lignocellulosic material as the carbon source · CPC title

• C12M45/02

  by mechanical forces; Stirring; Trituration; Comminuting (crushing, pulverizing, disintegrating in general B02C) · CPC title

• C12M21/12 Primary

  for producing fuels or solvents (C12M21/04 takes precedence; liquid carbonaceous fuels C10L1/00, solid fuels C10L5/00) · CPC title

• C12P7/06

  Ethanol, i.e. non-beverage · CPC title