REACTOR PUMP FOR CATALYZED HYDROLYTIC SPLITTING OF CELLULOSE

• US 20090143573A1
• Filed: 01/25/2008
• Published: 06/04/2009
• Est. Priority Date: 11/03/2006
• Status: Active Grant

• Current Assignee: David A. Olson
• Original Assignee: David A. Olson
• Inventors: Olson, David A.
• Granted Patent: US 7,815,741 B2
• Time in Patent Office: Days
• US Class Current: 536/128
• CPC Class Codes: C08H 8/00 Macromolecular compounds derived from lignocellulosic materials pretreatment thereof B27N
• CPC Class Codes: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: D21C 3/22 Other features of pulping processes
• CPC Class Codes: D21C 5/00 Other processes for obtaining cellulose, e.g. cooking cotton linters obtaining fibres for spinning D01C; Processes characterised by the choice of cellulose-containing starting materials
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

A reactor for hydrolytic splitting of cellulose under high pressure and heat has an inlet and outlet each with a cross-sectional area smaller than the cross-sectional area of the reactor. The pressure and heat in the reactor forms a cellulose plug within the inlet and the outlet. The inlet plug stops cellulose from escaping out the inlet. Cellulose begins to breakdown under heat, pressure, and if required an acid or a lubricant. The outlet plug slows downstream movement of cooking cellulose. Cellulose may be pre-treated by the addition of water, a weak acid, a lubricant, or a combination of the foregoing. The outer surface of the plug cooks faster than the inner core of the plug, becomes a liquefied slurry, and slides faster towards the outlet than the inner core.

Claims

1. A catalyzed hydrolytic process for splitting cellulose, comprising the steps of:

(a) selecting the type of cellulose for use as feedstock from the group of cellulose consisting of wood, logs, wood chips, lumber, newspaper, cardboard, corn fiber, corn cob without the corn, corn cob with the corn, sugar cane, straw, switch grass, other grasses, or any combination of the foregoing;

(b) pumping feedstock against compressed feedstock in a reaction chamber to form a feedstock plug, the feedstock plug moving downstream from an inlet to a discharge outlet of the reactor;

(c) subjecting the feedstock plug in the reaction chamber to a constellation of physical things selected from the group consisting of pressure, heat, steam, water, acid, a lubricant, or any combination the foregoing;

(d) cooking the feedstock plug within the reaction chamber;

(e) opening a discharge outlet of the reaction chamber to rapidly reduce the pressure in the reaction chamber upon the occurrence of an event, the event selected from the group consisting of reaching a pre-set pressure level in the reaction chamber, expiration of a pre-set period of time, or a combination of the foregoing; and

(f) whereby the selected cellulose is broken down into a liquefied slurry.

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

(a) selecting corn cob as the type of cellulose;

(b) grinding the corn cob;

(c) soaking the ground corn cob in water until the water content of the ground corn cob is in the range of about 40% to about 60%;

(d) selecting a lubricant as the type of physical thing;

(iv) mixing the lubricant with the soaked corn cob until the mixture of the soaked corn cob and the lubricant is about 25% by weight of lubricant and about 75% by weight of soaked corn cob.

3. The process of claim 2, comprising the steps of (a) selecting pressure and heat as types of physical things;

(b) subjecting the feedstock in the reaction chamber to a pressure in the range of about 100 psi to about 500 psi; and

(c) heating the feedstock in the reaction chamber to a temperature in the range of about 300°

F. to about 400°

F.

4. The process of claim 2, comprising selecting the point at which the lubricant is mixed with the soaked corn cob from the group consisting of the hopper-charging chamber, pumping chamber, reaction chamber, or a combination of the foregoing.

6. The process of claim 4, wherein the lubricant is mixed with the soaked corn cob through injector ports in the hopper-charging chamber, pumping chamber, reaction chamber, or any combination of the foregoing.

5. The process of claim 11, wherein the lubricant is selected from the group consisting of vegetable oil, corn oil, soy oil, saffron oil, sunflower oil, flax oil, olive oil, other oils non-miscible with water, grease, motor oil, air, water, or a combination of the foregoing.

7. The process of claim 11, comprising the steps of (i) comparing the downstream pressure on the upstream end of the feedstock plug and the back pressure in the reaction chamber and (ii) equalizing them if they are not equal.

8. The process of claim 11, wherein forming a plug of compressed feedstock, comprises the steps of:

(i) using high pressure to ram the feedstock into the reactor, the reactor having an inlet and a discharge outlet that are small relative to the interior of the reactor and (ii) holding the compressed feedstock in the reactor for a pre-set period of cook time to allow conversion of the feedstock to a liquefied slurry.

9. The process of claim 11, wherein cooking the feedstock plug comprises the steps of heating the cooking feed stock plug by the means selected from the group consisting of injecting steam directly into the reactor, heating the outer surface of the reactor to indirectly heat the cooking feedstock plug, flowing a heated substrate through a jacket surrounding the outer surface of the reactor, or any combination of the foregoing.

10. The process of claim 11, comprising the steps of (i) extending a cylinder against feedstock in a pumping chamber to compress the feedstock against a closed gate;

(ii) opening the gate upon the occurrence of an event selected from the group consisting of expiration of a pre-set time period, reaching a pre-set level of pressure on the upstream face of the gate, and extension of the cylinder to a pre-set position;

(iii) retracting the cylinder after the occurrence of a selected event; and

(iv) continuing the cycle of extension and retraction of the cylinder.