FOR MAKING THE SAME

[0001] The present application is claiming priority to U.S. Application Serial No. 14/756,904 filed on October 28, 2015, which is herein incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure generally relates to a fuel products that are problematic to burn. Such fuels include fuels made from grain, hop residues and solid animal waste (e.g., human waste). Fuels made from grain (e.g., spent grain) and hop residues are a byproduct of a brewing process. In addition, the present disclosure relates to a novel and improved process for making a fuel product from grain, hop residues and solid animal waste. The present disclosure also relates to the novel use of such a fuel product of grain, hop residue and solid animal waste as a primary fuel for a steam boiler in a brewing process or other applications.

BACKGROUND

[0003] Certain materials have traditionally been known as problematic sources of fuel.

These materials, however, often present great potential for reducing operating costs of fuel operated systems, conserving use of other fuel sources and for disposing unwanted materials. Examples of materials which have been traditionally problematic as alternative fuel sources include but are not limited to grains such as spent grain and distillers grains, hop residues and solid waste material from animals.

[0004] 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.

[0005] Similar problems have been shown to exist with respect to the use of hop residues and solid waste materials as a primary fuel source. One feature that is common to hop residues and solid waste materials is that each of these materials contain a relatively large amount of protein. Therefore, what is needed is a process which can reduce or break up the protein contained within these materials to render them suitable for use as an alternative fuel source.

[0006] Accordingly, the present disclosure provides a novel fuel product made from spent grain, distillers grains, hops residue, bio-solid waste material, or combinations thereof 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 and other applications.

[0007] The present disclosure further provides a novel and improved process for making a fuel product from spent grain and distillers grain using machines or devices that are

commercially available in industry.

[0008] The present disclosure further provides heat for a brewing process or other applications using a steam boiler fueled by a novel fuel product made from the spent grain, distillers grains and a hops residue byproduct of the brewing process.

[0009] The present disclosure also provides for fuel operated systems of various applications which incorporate the use of a novel fuel product made from bio-solid waste materials.

SUMMARY

[0010] In one form of the present disclosure, 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 .25 mm to .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. [0011] Provided is a process for making a combustible fuel product from hops residue comprising the following steps in any order: pulverizing the hops residue to reduce the particles to median particle size generally within the range of .25 mm to .6 mm with less than one percent (1%) of the hops residue particles greater than 2 mm; pressing the hops residue to mechanically remove moisture and other soluble components from the spent grain, drying the hops residue to reduce its moisture content to ten percent (10%) or less by weight and agitating the hops residue fuel product during a combustion phase to separate particles of the fuel product to inhibit their cohesion into an integrated mass.

[0012] In certain embodiments, the process includes the step of pressing the hops residue on a filter cloth to remove moisture and other soluble compounds from the hops residue through apertures in the cloth. In further embodiments, the process includes the step of subjecting the hops residue to a hammer mill to pulverize the hops residue. In further embodiments, the process includes the step of drying the hops residue in a heated rotating drum. In further embodiments, the process includes the step of applying said process to malt. In further embodiments, the process includes the step of directing pulses of air on the hops residue while on the filter cloth after they have been pressed to facilitate removal of the hops residue from the filter cloth.

[0013] Provided is a process for making a combustible fuel product from a biological waste material comprising the following steps in any order: removal of water, moisture and other soluble components from the biological waste material; drying the biological waste material to reduce the moisture content to 10% or less by weight; pulverizing the biological waste material to reduce the particle size to be within the range of 0.25 to 0.6 mm in size with less than 1% of the biological waste material particles being greater than 2 mm; and agitating the biological waste material during the combustion phase to separate particles of the biological waste material to inhibit their cohesion into an integrated mass. In certain embodiments, the biological waste material originates from waste water treatment activated sludge waste or from Animal Excreta. In further embodiments, the process includes the step of removal of water, moisture and other soluble components from the biological waste material comprises application of heat. In further embodiments, the process includes the step of subjecting the biological waste material to a hammer mill to pulverize the biological waste material. In further embodiments, the process includes the step of drying the biological waste material in a heated rotating drum. In further embodiments, the process includes the step of directing pulses of air on the biological waste material while on a filter cloth facilitate removal of the water, moisture and other soluble components from the filter cloth.

[0014] Provided is a process of making a combustible fuel product from oil seed pulp waste comprising the steps of: removing a high protein residue the oils seed pulp waste through an extraction process to obtain a moisture content of the grain to a value of ten percent (10%) or less and a particle size within range of .25 mm to .6 mm with less than 1% of the oil seed pulp waste being greater than 2 mm; optionally drying and pulverizing the oil seed pulp waste material to obtain a moisture content of the grain to a value of ten percent (10%) or less and a particle size within range of .25 mm to .6 mm with less than 1% of the oil seed pulp waste being greater than 2 mm, and agitating the oil seed pulp waste material during the combustion phase to separate particles of the oil seed pulp waste material to inhibit their cohesion into an integrated mass.

[0015] In certain embodiments, the step of separating any of the processed fuel products referred to above herein is effected by spraying the processed fuel product in a combustion chamber. In further embodiments, the spraying is accomplished through the use of a pneumatic stoker.

SUMMARY OF THE DRAWINGS

[0016] Other objects and advantages of the present disclosure 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 disclosure.

DETAILED DESCRIPTION

[0017] The present disclosure 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.

[0018] In one preferred form of the present disclosure, 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 .25 mm to .6 mm with less than 1% of the grain greater than 2 mm. The preferred, median, particle size between .25 mm to .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 form of the present disclosure, 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.

[0019] 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. This step removes water mechanically from the grain or fuel material which increases the overall thermal efficiency of the process and allowing excess heat to be available for other uses within the process. For example, heat vaporization of excess water wastes the application of heat energy which might be redirected for other beneficial uses such as steam generation.

[0020] The latter process steps reduce the moisture content to 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 disclosure, 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.

[0021] 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.

[0022] 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 disclosure 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 process of the present disclosure, a King Coal combustion chamber may be used. The process of the present disclosure 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.

[0023] In another preferred process of the present disclosure, 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 pneumatic stoker 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.

[0024] The above-described process can be described in the following four steps: 1) pulverizing the fuel material to reduce the particle size to be generally in the range of 0.25 to 0.6 mm with less than 1% of the fuel product being greater than 2 mm; 2) pressing the fuel material to mechanically remove moisture and other soluble components; 3) drying the fuel material to reduce the moisture content to 10% or less by weight; and 4) agitating the fuel product during the combustion phase to separate particles of the fuel product to inhibit their cohesion into an integrated mass. The above-described process steps reflect the order of steps for processing a spent grain fuel product for combustion as disclosed herein. However, in the case of other fuels, the order of steps for processing the fuel for combustion may differ and in some cases may eliminate the step of mechanically removing moisture and other soluble components from the fuel material as described in step 2). [0025] As previously mentioned, the steps described above may generally be applied to other fuel types in addition to spent grains. These other fuel types include distillers grains, hop residues, and bio-solid waste material. As is the case for spent grain, these fuel types present combustion challenges which are difficult to overcome due to their respective high protein content. For example, hop restudies from the processing or concentrating of hop alpha/beta acids and hop oils has a protein content of about 25%. Municipal waste water treatment activated sludge has a protein content of about 10%. Oil seed pulp wastes (e.g., sunflower or rape seed pulp) has a protein content of about 35%. Distillers grains, similar to brewers dried grains but from a distillery have a protein content of about 30%. All of these materials are characterized as high protein waste materials which can be used as fuel products. In each of these alternative fuel types, the degree of hydration and the degree of pulverizing to achieve the appropriate particle size distribution for combustion is dependent upon the respective particles adhesion

characteristics and the nitrogen bond (Protein) which results in cross-linking at the molecular level. For example, during thermal degradation, the nitrogen bonds in proteins cross link in a macro mechanical way which results in clumping, crusting or clinking of the fuel product. This restricts oxygen transmission into the burning fuel. The low moisture content obtained by the process step 3) and the small particle size obtained by process step 1) affects how quickly the temperature of the particle is raised to degrade the proteins. This arrests the particles tendency to adhere to each other via a nitrogen bond cross linkage. The small particle size obtained from step 1) and the agitation applied during step 4) keep the surface to oxygen exposure ratio appropriate for oxygen diffusion enabling complete appropriate combustion to be accomplished. Steps 1) and 4) work in conjunction to produce a combustible fuel product. For instance, if the small particles were allowed to easily touch during protein thermal degradation, they would form larger clumps. On the other hand, if the particles were too large to begin with, this would reduce the oxygen availability or diffusion necessary for complete combustion to occur.

[0026] As mentioned above, in the case of other fuels, the order of steps for processing the fuel for combustion may differ and in some cases, the step of mechanically removing moisture and other soluble components from the fuel material as described in step 2) may be eliminated. For example, in one embodiment, the pulverizing step (i.e., step 1) above) and the drying step (i.e., step 3) above) may need occur in a different order to ensure that fine particles do not re- adhere together as they are fed into the combustion chamber.

[0027] To make a fuel product from hops residue, the hops must be processed to extract out essential oils. The processing of hops to extract the essential oils leaves a high protein residue. In order to process the hops, a hop processor first dries the hops, next grinds the dry hops cones and then uses a CO2 critical (triple) point extraction to remove the essential oils. The waste or hops residue is then dried and pre-ground. In some embodiments, the hops residue is dried and pre-ground in a pressed board like form and is then reground to a power. As described above, the process steps for making a fuel product from hops residue may occur in any order.

[0028] To make a fuel product from biological waste material, one can process Municipal Waste Water Treatment Activated Sludge Waste, which is a human bio-hazard. This biological waste material starts off very wet (90% ater). This fi st step is therefore to de water the biological waste material as much as possible using flocking agents, centrifuges and dewatering separators. The biological waste material will then be dried typically on a belt or drum filter. This results in dry flakes which are large and which will need to be pulverized. Thus, the processing of biological waste material into a fuel product requires the following steps: 1) removal of water, moisture and other soluble components from the biological waste material; 2) drying the biological waste material to reduce the moisture content to 10% or less by weight, 3) pulverizing the biological waste material to reduce the panicle size to be within the range of 0.25 to 0.6 mm in size with less than 1% of the biological waste material particles being greater than 2 mm; and 4) agitating the biological waste material during the combustion phase to separate particles of the biological waste material to inhibit their cohesion into an integrated mass. It is noted that step 2) uses any means within the purview of an individual of suitable skill in the art to remove free water. Also, the high water content of the biological waste material requires the application of additional heat to the waste material in the drying step. In general, Municipalities have an interest in applying the disclosed process not only for heat generation but more importantly, in order to dispose of bio-hazardous material via combustion . The combustion process may occur within either a steam boiler or an incinerator.

[0029] H To make a fuel product from Animal Excreta, one can process the Animal Excreta in a manner similar to the process steps described above with respect to biological waste material. Animal Excreta, is a bio-hazard which also starts off very w ^? et. This fecal material is first dewatered using centrifuges and dewatering separators to separate out the settable solids. Next, the settable solids are dried on a belt or drum filter. The resulting dry flakes are then pulverized. Thus, the processing of Animal Excreta into a fuel product requires the following steps: 1) removal of water, moisture and other soluble components from the Animal Excreta; 2) drying the Animal Excreta to reduce the moisture content to 10% or less by weight; 3) pulverizing the Animal Excreta to reduce the particle size to be within the range of 0.25 to 0.6 mm in size with less than 1% of the Animal Excreta particles being greater than 2 mm; and 4) agitating the Animal Excreta during the combustion phase to separate particles of the Animal Excreta to inhibit their cohesion into an integrated mass. It is noted that step 2) uses any means within the purview of an individual of suitable skill in the art to remove free water. Also, the high water content of the biological waste material requires the application of additional heat to the waste material in the drying step. This process may be applied by Farms to not only generate some form of heat recovery but more importantly, to dispose of a bio-hazardous material rather than holding it until growing season (farms hold this material for up to a full year) for land application as fertili er, to reduces smells and to reduce the liability of having these exposed standing waste ponds which EPA regulates stringently.

[0030] To make a fuel product from oil seed pulp waste, the oil seed pulp waste undergoes a grain oil extraction. In the extraction process, high protein residue is removed from the oil seed pulp waste material (which is already dry (shelf stable)) and ground ready for animal feed processing. Additional drying and pulverizing steps may be applied to the oil seed pulp waste material as described above as deemed necessary. For example, in certain embodiments, the oil seed pulp waste material may be dried to reduce the moisture content to 10% or less by weight and then pulverized the or vice versa to reduce the particle size to be within the range of 0.25 to 0.6 mm in size with less than 1 % of the oil seed pulp waste material particles being greater than 2 mm. The oil seed pulp waste material is then agitated during the combustion phase to separate particles of the oil seed pulp waste material to inhibit their cohesion into an integrated mass. The agitation step may occur immediately after the extraction step or may occur after a drying and pulverizing as described above. Oil seed pulp waste streams have a fairly high heating value. [0031] To make a fuel product from distillers grains one would follow the process described above with respect to the processing of brewery spent grains. In this regard, distillers dried grains are regarded by those of skill in the art to be similar to those of brewers dried spent grains. In addition, the process described above may also be applied to other types of high protein waste from grains as well as grain wastes not associated with the manufacture of alcoholic beverages (e.g., rape seed).

[0032] In each of the processes described above with respect to hops residues, biological waste materials, oil seed pulp waste and brewers dried spent grains, one the agitation step may be applied by a pneumatic stoker or by an auger which drops the grain onto an included bed and transfers the fuel product to the combustion chamber through an incline. However, the pneumatic stoker, by blowing the particles into the combustion chamber, keeps the particles separated in the combustion chamber long enough so that the heat transfer quickly degrades the proteins preventing their nitrogen cross linking that would have the particles sticking to each other. This feature for degrading proteins is not provided for by traditional feeding mechanisms into the combustion chamber.

[0033] With respect to the combustion of these high protein fuel products (hops residue, biological waste materials, oils seed pulp waste and distillers grains) one would assume that these fuel products would have abnormally high NOX emissions due to the high protein and organic nitrogen content of these fuels. However, the present process does not result in elevated nitrous oxide formation. Rather, the present process results in emissions which are within the normal regulatory compliant range of NOX production for typical fuels. This is due to the relatively weak binding of nitrogen to the carbon based proteins. In essence, the chemical path of protein thermal decomposition allows the nitrogen to take an intermediate step to form ammonia in the present process. It is noted that ammonia is sometimes injected into combustion furnaces for boilers to lower NOX production. NH ₃ (ammonia) + NOX (nitros oxides) = N2 (nitrogen) + H2O (water). The present process does not necessarily require the injection of ammonia into the combustion chamber due to the protein thermal decomposition which occurs during the process. In any event, the presence of ammonia formed from the present process within the combustion chamber allows higher temperatures in the combustion chamber which typically produces higher NOX production and which keeps NOX in check. [0034] Although certain specific steps and devices for performing the steps of the process of the present disclosure 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 disclosure indicated in the appended claims. It will also be apparent that the present disclosure may be applied to grains other than malt which is disclosed for illustrative purposes only. It will also be apparent that the present disclosure 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 disclosure may be applied to Distillers Spent Grain (DDG).