Method for Pretreatment of Cellulosic and Lignocellulosic Materials for Conversion into Bioenergy

• US 20110117619A1
• Filed: 07/06/2010
• Published: 05/19/2011
• Est. Priority Date: 07/06/2009
• Status: Active Grant

• Current Assignee: Brigham Young University (The Church of Jesus Christ of Latter-Day Saints)
• Original Assignee: Brigham Young University (The Church of Jesus Christ of Latter-Day Saints)
• Inventors: Hansen, Jaron C., Hansen, Lee D.
• Granted Patent: US 8,449,773 B2
• Time in Patent Office: Days
• US Class Current: 435/167
• CPC Class Codes: C10G 1/00 Production of liquid hydrocarbon mixtures from oil-shale, oil-sand, or non-melting solid carbonaceous or similar materials, e.g. wood, coal mechanical winning of oil from oil-shales, oil-sand, or the like B03B
• CPC Class Codes: C10G 1/047 Hot water or cold water extraction processes
• CPC Class Codes: C12P 2201/00 Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis
• CPC Class Codes: C12P 3/00 Preparation of elements or inorganic compounds except carbon dioxide recovery of carbon dioxides as by-products C12F3/02
• CPC Class Codes: C12P 5/023 Methane
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel
• CPC Class Codes: Y02W 10/37 using solar energy

Abstract

A process for converting organic waste materials into usable products and products thereof is disclosed. According to the process, organic waste materials are contacted with an oxidant to form a product and then an amount of the oxidant is removed from the product to form a reactor-ready feedstock. The oxidant is removed by various means, including washing, photolysis, catalytic means, oxidation of the oxidant, reduction of the oxidant, and heat. The reactor-ready feedstock may then be introduced into a reactor, such as a digester or incubator, and the reactor-ready feedstock is converted by microorganisms into biofuel or other products.

Claims

1. A process for treating organic materials comprising the steps of

a) providing an aqueous slurry comprising organic materials;

b) contacting said aqueous slurry with a solution comprising an amount of peroxide;

c) forming a mixture comprising said aqueous slurry and said solution, wherein the concentration of peroxide in said mixture is at least 1 ppm, said amount of peroxide being sufficient to oxidize at least a portion of said organic materials into an oxidized product; and

,

d) removing a portion of said amount of any peroxide from said mixture.

2. The process of claim 1, further comprising the steps of

contacting said oxidized product with at least one microorganism in a reactor;

converting said oxidized product into a metabolic product, said metabolic product comprising a hydrocarbon gas; and

collecting said product.

3. The process of claim 1, further comprising the steps of

contacting said oxidized product with at least one microorganism;

converting said oxidized product into a metabolic product, said metabolic product comprising hydrogen gas; and

collecting said product.

4. The process of claim 1, wherein the step of removing a portion of said amount of any peroxide from said mixture is actuated by converting

a portion of said amount of any peroxide from said mixture into nonperoxide compounds.

5. The process of claim 2, wherein the concentration of said any peroxide in said mixture is sufficiently decreased to a level so that an amount of foam formed in said reactor is decreased;

wherein the step of removing a portion of said amount of any peroxide from said mixture forms an oxidized product, said oxidized product consisting of a remaining amount of peroxide and an amount of organic waste, and wherein said remaining amount of peroxide is sufficiently low in concentration so that said at least one microorganism forms some metabolic product.

6. The process of claim 4, further comprising the step of

photolyzing at least a portion of said amount of said at least one oxidant, thereby deactivating at least 5% of said amount of said at least one oxidant.

7. The process of claim 1, further comprising the steps of

photolyzing at least a portion of said amount of said at least one oxidant for a first period of time;

photolyzing said organic materials for said first period of time, wherein the steps of photolyzing said at least a portion of said amount of said at least one oxidant and photolyzing said organic materials accelerates the rate at which said organic material is converted into oxidized product;

photolyzing at least a portion of said amount of said at least one oxidant for a second period of time; and

,

photolyzing at least a portion of said organic materials, wherein the steps of

1) photolyzing said at least a portion of said amount of said at least one oxidant and

2) photolyzing at least a portion of said organic materials decelerates the rate at which organic material is converted into oxidized product.

8. The process of claim 3, wherein said gas is at least one of the following selected from the

group consisting of methane and hydrogen.

9. The process of claim 1, wherein said at least one oxidant is a peroxide, and wherein said at least one microorganism comprises a

methanogenic bacteria and wherein said hydrocarbon gas comprises methane.

10. The process of claim 1, wherein said oxidized product is washed with at least one solution, wherein said at least one solution is selected from the group comprising consisting of water, distilled water, deionized-distilled water, polar substances, catalysts, oxidizing agents, reducing agents, and combinations thereof.

11. The process of claim 8, wherein the step of removing said peroxide is actuated by a method selected from the group consisting of:

decanting, filtering, chemical methods, photolysis, irradiation, and combinations thereof.

12. The process of claim 1, wherein a ratio of moles of said at least one oxidant to moles of said organic materials is at least greater than 1 mole of oxidant to 100 moles of organic material.

13. The process of claim 1, wherein the ratio of moles of oxidant to moles of lignocellulosic material in said organic material is greater than 1 mole of oxidant to 100 moles of lignocellulosic material.

14. The process of claim 13, further comprising the step of exposing said at least one oxidant to wavelengths of electromagnetic light, wherein said wavelengths are greater than 189 nm and less than 401 nm.

15. The process of claim 13, wherein said organic materials comprises at least one of the following:

materials selected from the group consisting of food industry waste, animal waste, paper industry waste, municipal solid waste, tire waste, petroleum refining waste, and biomass.

16. The process of claim 11, wherein the step of removing a portion of said amount of said

oxidant is actuated by performing at least one of the methods that is selected from the group consisting of:

washing the first product with a solution;

washing the first product with a solution comprising oxygen;

decanting the solution;

filtering the solution;

exposing the first product to ultraviolet light, wherein the wavelengths of the ultraviolet light are inclusively between 190 nm and 350 nm in length;

photolyzing said oxidized product;

photolyzing at least a portion of said amount of said oxidant;

irradiating said first product; and

combinations thereof.

17. The process of claim 1, wherein said at least one oxidant is selected from the group

consisting of hydrogen peroxide, peroxide, sodium percarbonate, sodium peroxycarbonate, sodium peroxide, calcium peroxide, organic peroxides, barium peroxide, superoxides, oxygen, and any compound capable of producing a peroxide in water.

20. The process of claim 1, wherein said oxidized product is washed with at least one

solution, wherein said at least one solution is selected from the group comprising consisting of water, distilled water, deionized-distilled water, polar substances, catalysts, oxidizing agents, reducing agents and combinations thereof.

18. A method of producing methane from organic materials comprising

a) providing an amount of organic material;

b) forming a slurry from the amount of organic material;

c) mixing the amount of organic material with an amount of peroxide solution;

wherein a product is formed;

d) combining the product with a chemical solution, wherein a pretreated substance is formed;

e) removing a portion of the peroxide contained in the pretreated substance;

f) incubating the pretreated substance in a reactor for an amount of time sufficient to convert a portion of the product into an amount of methane.

19. The method of claim 18, wherein the product that has been substantially freed from peroxide contains a sufficiently low concentration of said peroxide, wherein said oxidized product is substantially free from foam when introduced into the reactor, wherein said reactor is selected from the group consisting of anaerobic reactors and partially-anaerobic reactors.