U.S. patent application number 14/756904 was filed with the patent office on 2017-08-31 for spent grain fuel product and process.
This patent application is currently assigned to AKBEV GROUP, LLC. The applicant listed for this patent is AKBEV GROUP, LLC. Invention is credited to Curtis Holmes, Geoffrey L. Larson, Brandon Michael Smith, David D. Wilson.
Application Number | 20170247623 14/756904 |
Document ID | / |
Family ID | 58631941 |
Filed Date | 2017-08-31 |
United States Patent
Application |
20170247623 |
Kind Code |
A9 |
Larson; Geoffrey L. ; et
al. |
August 31, 2017 |
Spent grain fuel product and process
Abstract
A process of making a fuel product from spent grain from a beer
brewing process. In the brewing process, the grain is pulverized to
a particle size whose mean particle size is approximately 0.25 mm
to 0.6 mm with less than 1% greater than 2 mm. After the brewing
sugars are extracted from the grain, the spent grain is pressed
against a filter to reduce moisture below sixty-five percent (65%),
and then the grain is dried to further reduce its moisture to less
than ten percent (10%). The dried spent grain, after the
aforementioned processing, is fed into a combustion chamber for a
steam boiler that is used for beer brewing, and the spent grain is
separated during combustion by agitation such as spraying of the
grain in the combustion chamber.
Inventors: |
Larson; Geoffrey L.;
(Juneau, AK) ; Smith; Brandon Michael; (Chico,
CA) ; Holmes; Curtis; (Juneau, AK) ; Wilson;
David D.; (Juneau, AK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AKBEV GROUP, LLC |
Juneau |
AK |
US |
|
|
Assignee: |
AKBEV GROUP, LLC
Juneau
AK
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20170121619 A1 |
May 4, 2017 |
|
|
Family ID: |
58631941 |
Appl. No.: |
14/756904 |
Filed: |
October 28, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13199505 |
Sep 1, 2011 |
9447354 |
|
|
14756904 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y02E 50/10 20130101;
C10L 2290/30 20130101; C10L 2290/544 20130101; Y02E 50/30 20130101;
C10L 2290/145 20130101; C10L 2290/06 20130101; C10L 2250/06
20130101; C10L 2290/547 20130101; C10L 2290/24 20130101; C10L
2290/08 20130101; C10L 2290/28 20130101; C10L 5/445 20130101; C10L
2200/0469 20130101; C10L 5/42 20130101; C10L 5/366 20130101; C10L
5/44 20130101; F23B 1/02 20130101; C10L 9/00 20130101; C10L 2290/18
20130101 |
International
Class: |
C10L 5/44 20060101
C10L005/44; C10L 9/00 20060101 C10L009/00; F23B 30/00 20060101
F23B030/00; C10L 5/36 20060101 C10L005/36 |
Claims
1. A process for making a fuel product from spent grain comprising
the following steps: in a brewing process pulverizing grain to
reduce the particles to median particle size generally within the
range of 0.25 mm to 0.6 mm with less than one percent (1%) of the
grain particles greater than 2 mm, after brewing, pressing the
spent grain to mechanically remove moisture and other soluble
components from the spent grain, and drying the spent grain to
reduce its moisture content to ten percent (10%) or less by
weight.
2-3. (canceled)
4. The process defined in claim 1 including the step of pressing
the spent brewing grains on a filter cloth to remove moisture and
other soluble compounds from the spent grain through apertures in
the cloth.
5. The process defined in claim 1 including the step of subjecting
the grain to a hammer mill to pulverize the grain.
6. The process defined in claim 1 including the step of drying the
spent grain in a heated rotating drum.
7. The process defined in claim 1 including the step of applying
said process to malt.
8. The process defined in claim 1 including the step of pressing
the spent grain on a filter to reduce the moisture in the grain
below sixty-five percent (65%).
9. The process defined in claim 4 including the step of directing
pulses of air on the spent grains while on the filter cloth after
they have been pressed to facilitate removal of the spent grain
from the filter cloth.
10. A fuel product made from spent grain in accordance with the
process defined in claim 1.
11. A combustible fuel product comprising spent grain whose
particles have a median size generally within the range of 0.25 mm
to 0.6 mm, and said particles having a moisture content of ten
percent (10%) or less by weight.
12. The fuel product defined in claim 11 wherein less than one
percent (1%) of said particles is greater than 2 mm in size.
13. A process of making a combustible fuel product from grain
comprising the steps of: removing the moisture content of the grain
to a value of ten percent (10%) or less, reducing the size of the
particles of the grain to a size generally within range of 0.25 mm
to 0.6 mm, and wherein the grain is spent grain from a brewing
process.
14. The process defined in claim 13 wherein less than one percent
(1%) of the grain particles is greater than 2.0 mm in size.
15. The process defined in claim 13 wherein the moisture content of
the grain is reduced to ten percent (10%) or less after the brewing
process when the grain is spent.
16. The process defined in claim 13 wherein the size of the grain
particles is reduced to generally within said range of 0.25 mm to
0.6 mm during the brewing process.
17. The process defined in claim 13 including the steps of
combusting the grain after it becomes spent and is reduced in size
and moisture as defined in claim 13 and the spent grain is sprayed
during combustion to separate particles of spent grain to inhibit
their cohesion into an integrated mass.
18. (canceled)
19. (canceled)
20. (canceled)
21. The process defined in claim 17 utilizing a pneumatic stoker to
spray the grain during combustion.
22. The process defined in claim 21 wherein the grain is sprayed
into a combustion chamber using a pneumatic stoker.
Description
[0001] The present application is a continuation in part of our
pending U.S. application, Ser. No. 13/199,505 filed Sep. 1,
2011.
[0002] The present invention generally relates to a fuel product
made from grain, preferably spent grain such as that which is a
byproduct of brewing. In addition, the present invention relates to
a novel and improved process for making a fuel product from spent
grain. The present invention also relates to the novel use of such
a fuel product of spent grain as a primary fuel for a steam boiler
in a brewing process.
BACKGROUND OF PRESENT INVENTION
[0003] Spent grain from the brewing of alcoholic products has been
used as a food product such as cattle feed. In some of the
processes used to make the food product it is known to reduce the
moisture content of the spent grain through press and/or drying
operations. Although there have been some attempts to use spent
grain as a major part of the fuel used for a steam boiler, such
attempts have been unsuccessful due to insufficient or failure of
combustion and excessive smoke produced thereby. Although there
have been successful attempts to use spent grain as a minor part of
the fuel for a steam boiler, attempts to use spent grain as the
sole or primary fuel have been unsuccessful due to insufficient or
failure of combustion and excessive smoke produced thereby.
OBJECTS OF THE PRESENT INVENTION
[0004] A primary object of the present invention is to provide a
novel fuel product made from spent grain and a novel and improved
process for making this fuel product. Included herein is such a
fuel product that can be used in a steam boiler or other fireboxes
in conformance with present day environmental and emission laws and
regulations. Further included herein is such a fuel product that
can be successfully used as the sole or primary fuel for a steam
boiler used such as in brewing.
[0005] A further object of the present invention is to provide a
novel and improved process for making a fuel product from spent
grain using machines or devices that are commercially available in
industry.
[0006] Another object of the present invention is to provide heat
for a brewing process using a steam boiler fueled by a novel fuel
product made from the spent grain byproduct of the brewing
process.
SUMMARY OF A PREFERRED FORM OF THE PRESENT INVENTION
[0007] In one preferred form of the present invention, a fuel
product is made from the spent grain byproduct of a process for
brewing beer from malt and other grains. During or after the
brewing process, the spent grain is processed to sufficiently
reduce its median particle size to preferably 0.25 mm to 0.6 mm
with less than 1% of the grain greater than 2 mm. The wet spent
grain is pressed on a mash filter press to reduce moisture below
sixty-five percent (65%) and reduce soluble sugars and proteins. No
longer needed for brewing, the spent grain is next dried to reduce
its moisture content to ten percent (10%) or less by weight. The
spent grain is then moved downward through a combustion chamber of
a steam boiler and is agitated or vibrated during its combustion to
further break up the structure of the burning spent grain thereby
preventing the formation of a solid mass of spent grain which will
prevent sufficient combustion.
DRAWING
[0008] Other objects and advantages of the present invention will
become apparent from the following detailed description taken in
conjunction with the attached drawing which is a schematic flow
diagram of a preferred process of the present invention.
DETAILED DESCRIPTION
[0009] The present invention provides a novel fuel product made
from spent grain that is processed to change its composition and
structure in order to sufficiently increase its combustibility to
allow it to be used as a fuel product in accordance with air
quality standards and other environmental regulations and law.
[0010] In one preferred form of the present invention, the spent
grain is primarily malt byproduct of a beer brewing process shown
for illustrative purposes only in the drawing. During brewing the
grain is first crushed or pulverized by a hammer mill 10 to reduce
it to a finely ground median particle size generally within the
range of 0.25 mm to 0.6 mm with less than 1% of the grain greater
than 2 mm. The preferred, median, particle size between 0.25 mm to
0.6 mm means that fifty percent (50%) of the grain particle mass is
greater than and fifty percent (50%) of grain particle mass is
smaller than the median size. Pulverizing of the grain reduces the
adhesion among the elements of the grain which normally serve to
solidify the grain into one cohesive and air-impermeable mass upon
combustion. It also increases the surface area of the particles to
facilitate the reduction of moisture and increase combustibility.
In one preferred form of the present invention, the mill used in
this instance is a Meura ClassicMill CLM3 model fine grinding
hammer mill with horizontal shaft. This grinding process to obtain
the desired particle size, for combustion, can be accomplished
before or after the brewing and drying process, prior to
combustion. Any other suitable device may be used to pulverize the
grain.
[0011] After pulverizing, the grain is moved such as by a drag
chain conveyor to a mash vessel 12 and hydrated from which it is
moved such as by a centrifugal pump to a mash filter press 14 where
it is pressed. The latter process reduces its moisture content
below 65% and removes soluble sugar and protein contents which act
as adhesive during subsequent drying of the spent grain. With these
compounds reduced, the tendency of the grain particles to establish
cohesion and structural integrity during subsequent drying and
burning as a fuel will be significantly reduced. The fact that the
spent grain has been pulverized, also enables the filter to be a
cloth through which the moisture passes when the spent grain is
pressed on the cloth. The latter also reduces the energy needed to
further dry the spent grains before its use as fuel. In one
preferred process of the present invention, a Meura 2001 mash
filter press available in the industry may be used. However other
methods and devices may also be used to press the moisture and
other soluble compounds from spent grain as described above. Due to
the compression of the spent grains to remove moisture, it is
preferred that air pulses be directed into the spent grain on the
filter cloth before opening the filter to help break up the spent
grain cake to facilitate release of the spent grain from binding to
the filter cloth when the filter is opened. The spent grain is then
moved to a hopper by a pneumatic pump from which it is moved to a
grain drying drum 18 by an auger and pulled through the drier drum
by a pneumatic fan, for example.
[0012] The next step in the process is that the present spent grain
is dried to further reduce the moisture content from sixty-five
percent (65%) to ten percent (10%) by weight or less. In the
preferred embodiment, a rotating dryer drum 18 is used to receive
the spent grain and is rotated while heated air in the drum
subjects the spent grain to the desired drying while the drum is
rotating. The reduced finely ground spent grain particles help
speed up the drying process to reach the desired moisture level
preferably ten percent (10%) or less by weight in order to increase
its combustibility. A suitable dryer drum that can be used is one
made by Baker Rullman which is readily available on the market.
Other methods of drying the spent grain to sufficiently reduce its
moisture content may of course be used. Also, grinding the dried
spent grain can be done after the drying process to achieve the
desired particle size distribution.
[0013] After having been processed as described above, the spent
grain can be stored in a hopper 20 for immediate or eventual use as
the sole fuel for example in the boiler 22 in a brewery used to
produce steam for heating the brew house vessels. In the shown
embodiment the dried spent grain is moved to the hopper 20 by a
cyclone. Auger 24 is used to convey the spent grain fuel into the
combustion chamber 28. For combustion within the boiler 28 the
spent grain is moved in any suitable manner preferably down an
inclined grate 26 through the combustion chamber 28 while the grate
26 is agitated or vibrated. In one preferred process, a motor 30
connected by linkage 32 to the grate 26 is employed to vibrate the
grate as the spent grain is moved through the combustion chamber
28. The timing frequency and intensity of the inclined grate
agitation can be controlled and adjusted as needed for best
combustion. The angle of the inclined grate being combined with the
agitation or vibration of the grate helps to keep the spent grain
moving through the combustion chamber while it burns to inhibit
cohesion and solidification of its particles. Under normal
circumstances, spent grain that has not been processed as described
above, when heated tends to form a sponge-like impermeable,
cohesive mass which inhibits the transfer of oxygen and heat to the
interior of the mass and thereby prevents sufficient combustion and
smoke while also causing an excessive buildup of material within
the combustion chamber. However the process of the present
invention not only sufficiently reduces the moisture and particle
size in the spent grain, soluble proteins and sugars which act as
binding agents during heating which can inhibit combustion. In
addition, the vibration and continual movement of the spent grain
through the combustion chamber further breaks up the spent grain
into smaller clumps thereby avoiding cohesion of the particles into
a non-porous, cohesive mass with insufficient heat transfer and
oxygen into the interior of the mass. In one preferred process of
the present invention a King Coal combustion chamber may be used.
The process of the present invention provides effective combustion
of the spent grain to allow it to be used as the sole source of
fuel, that is, without the need of combining it with wood, oil,
gas, coal or other combustibles.
[0014] In another preferred process of the present invention,
rather than separating the spent grain particles during combustion
by vibrating or agitating the particles through means of the grate
26, linkage 32 and motor 30 as described above, the spent grain
particles are separated and disbursed during combustion by being
introduced or fed into the combustion chamber by a pneumatic
stoker. The latter sprays the spent grain particles into the
combustion chamber thereby separating and disbursing the particles
and igniting and burning them while they are in suspension and
separated from each other and before they can land and adhere to
each other on the grate or other bed. This method also increases
the oxygen flow and combustion to allow the spent grain to be used
as the sole fuel source in brewery boilers.
[0015] Although certain specific steps and devices for performing
the steps of the process of the present invention have been
disclosed above, it will be apparent to one of ordinary skill in
the art that other steps and devices may be used without departing
from the scope of the present invention indicated in the appended
claims. It will also be apparent that the present invention may be
applied to grains other than malt which is disclosed for
illustrative purposes only. It will also be apparent that the
present invention may be applied to other processes other than
brewing which is disclosed for illustrative purposes only. For
example, in addition to Brewers Spent Grains (termed BDG in the
art) described above, the present invention may be applied to
Distillers Spent Grain (DDG).
* * * * *