Method for impregnating biomass and device for impregnating biomass

Patent metadata

Field	Value
Publication number	US-11186949-B2
Application number	US-201716348794-A
Country	US
Kind code	B2
Filing date	Dec 7, 2017
Priority date	Dec 8, 2016
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

The invention relates to a method for impregnating biomass (10). In a step (S100) of the method, a reactor unit (11) is fed with biomass (10) by means of a plug screw (12). In another step (S200), the reactor unit (11) is at least partially filled up to a predetermined fill level (13) with a reactant (18), such that a reaction between the fed biomass (10) and the reactant (18) takes place in order to obtain an impregnated biomass. In another step (S300), the impregnated biomass (10) is discharged from the reactor unit (11) for further processing (S300). The invention further relates to a device (1) for impregnating biomass (10).

First claim

The invention claimed is:

1. A method for impregnating biomass ( 10 ), the method comprising:
feeding a reactor unit ( 11 ) with biomass ( 10 ) by means of a plug screw ( 12 , S 100 );
conveying the biomass ( 10 ) by means of at least one conveyer screw ( 15 ) within the reactor unit ( 11 ) during impregnation of the biomass ( 10 , S 210 );
at least partially filling the reactor unit ( 11 ) up to a predetermined fill level ( 13 ) with a reactant ( 18 ), such that a reaction between the fed biomass ( 10 ) and the reactant ( 18 ) takes place in order to obtain an impregnated biomass (S 200 );
controlling the fill level ( 13 ) such that it is constant over a predetermined time by regulating inflow of the reactant ( 18 ) into the reactor unit ( 11 );
determining the fill level ( 13 ) depending on the velocity with which the biomass ( 10 ) is conveyed through the reactor unit ( 11 ), wherein the velocity is regulated by rotational velocity of the conveyor screw ( 15 ); and
discharging the impregnated biomass ( 10 ) from the reactor unit ( 11 ) for further processing (S 300 ).

2. The method for impregnating biomass ( 10 ) of claim 1 further comprising compressing the biomass ( 10 ) by means of the plug screw ( 12 ) before feeding the biomass ( 10 ) into the reactor unit ( 11 , S 20 ).

3. The method for impregnating biomass ( 10 ) of claim 2 further comprising pre-compressing the biomass ( 10 ) by means of a force feed screw ( 14 ) before feeding the biomass ( 10 ) into the reactor unit ( 11 , S 10 ).

4. The method for impregnating biomass ( 10 ) of claim 2 , wherein the volumetric compression ratio during compression with the plug screw ( 12 ) is between 1.5 and 6.

5. The method for impregnating biomass ( 10 ) of claim 4 , wherein the volumetric compression ratio during compression with the plug screw ( 12 ) is between 1.7 and 3.

6. The method for impregnating biomass ( 10 ) of claim 4 , wherein the volumetric compression ratio during compression with the plug screw ( 12 ) is about 1.9.

7. The method for impregnating biomass ( 10 ) according to claim 1 further comprising removing residual reactant ( 18 ) from the impregnated biomass ( 10 ) in a further processing step (S 400 ) following the discharge (S 300 ) of the impregnated biomass ( 10 ) out of the reactor unit ( 11 ); supplying the residual reactant ( 18 ) into a recirculation circuit ( 17 ); and providing the reactant ( 18 ) to be filled into the reactor unit ( 11 ) from the recirculation circuit ( 17 ) and/or from a reservoir ( 16 ).

8. The method for impregnating biomass ( 10 ) according to claim 1 further comprising controlling a constant fill level ( 13 ) of the reactant ( 18 ) within the reactor unit ( 11 ) such that the biomass ( 10 ) can be homogeneously impregnated during a specified impregnation time.

9. The method for impregnating biomass ( 10 ) according to claim 1 further comprising controlling an amount of reactant ( 18 ) filled into the reactor unit ( 11 ) in dependence on a pH-value of the impregnated biomass ( 10 ) discharged from the reactor unit ( 11 ) and/or on a pH-value of the reactant ( 18 ) filled into the reactor unit ( 11 ).

10. The method for impregnating biomass ( 10 ) according to claim 1 further comprising controlling a temperature and/or a pressure to be provided within the reactor unit ( 11 ) during impregnation (S 230 ).

11. The method for impregnating biomass ( 10 ) according to claim 1 further comprising feeding the reactor unit ( 11 ) by means of a plug screw ( 12 ) in a first direction before conveying the biomass ( 10 ) along a longitudinal axis of the reactor unit ( 11 ) during impregnation, the longitudinal axis ( 22 ) being substantially perpendicular to the first direction, wherein a ratio between an extension of the reactor unit ( 11 ) along the longitudinal axis ( 22 ) and a width of the reactor unit ( 11 ) is at least 2.

12. The method for impregnating biomass ( 10 ) according to claim 1 further comprising interrupting the feed of biomass ( 10 ) into the reactor unit ( 11 ) by means of a retaining member ( 23 ) that is arranged upstream of the reactor unit ( 11 , S 110 ).

13. The method for impregnating biomass ( 10 ) according to claim 1 , wherein the reactant is a liquid comprising chemicals selected from the group consisting of an acid, a catalyst or mixtures thereof.

14. A device ( 1 ) for impregnating biomass ( 10 ), the device comprising:
a compression unit ( 40 ) having an outlet; and
a reactor unit ( 11 ) having an inlet;
wherein:
the outlet of the compression unit ( 40 ) is connected to the inlet of the reactor unit ( 11 );
the compression unit ( 40 ) comprises a plug screw ( 12 ) which is configured for feeding the biomass ( 10 ) into the reactor unit ( 11 );
the reactor unit ( 11 ) is configured for being at least partially filled with a reactant ( 18 ) up to a predetermined fill level ( 13 ) such that a homogeneous impregnation of the fed biomass ( 10 ) takes place when the biomass ( 10 ) is conveyed within the reactor unit ( 11 ) by means of conveyor screw ( 15 );
the reactor unit ( 11 ) is configured for controlling the fill level ( 13 ) such that it is constant over a predetermined time by regulating inflow of a reactant ( 18 ) into the reactor unit ( 11 ); and
the reactor unit ( 11 ) is configured for determining the fill level ( 13 ) depending on the velocity with which the biomass ( 10 ) is conveyed through the reactor unit ( 11 )), wherein the velocity is regulated by rotational velocity of the conveyor screw ( 15 ).

15. The device ( 1 ) for impregnating biomass ( 10 ) of claim 14 , wherein the reactor unit ( 11 ) is at least partially manufactured of a material that is resistant to corrosion.

16. The device ( 1 ) for impregnating biomass ( 10 ) of claim 14 , wherein the plug screw ( 12 ) of the compression unit ( 40 ) is configured for feeding the biomass ( 10 ) into the reactor unit ( 11 ) in a first direction ( 30 ); and wherein the conveyor means ( 15 ) of the reactor unit ( 11 ) is configured for conveying the biomass ( 10 ) within the reactor unit ( 11 ) along a longitudinal axis ( 22 ) of the reactor unit ( 11 ), the longitudinal axis ( 22 ) being substantially perpendicular to the first direction ( 30 ).

Assignees

• Valmet Oy

Inventors

• Averheim Andreas
• Grundström Per
• Löfström Anders

Classifications

• D21C7/12

  Devices for regulating or controlling · CPC title

• D21C7/00

  Digesters · CPC title

• D21C1/00 Primary

  Pretreatment of the finely-divided materials before digesting (of waste paper D21C5/02) · CPC title

• D21C1/10

  Physical methods for facilitating impregnation · CPC title

• D21C7/06

  Feeding devices · CPC title