Patent Application
20080134572
The present invention relates generally to combustible fuels, in particular to a method for making a combustible fuel briquette.
Many efforts have been made to produce fuels for barbecuing that are clean-burning, easy to handle, and easily ignitable. Charcoal, usually made from a wood base, is the most common component of fuels for barbecuing. Charcoals having vegetable and coal bases have also been used. Such fuels are usually difficult to ignite and often require the use of an ancillary flammable material, such as lighter fluid or newspaper, to create a flame of sufficient intensity and duration to ignite the charcoal.
Previous efforts to make charcoal fuel easier to ignite have involved the impregnation of charcoal with a more flammable “starting” compound, such as lighter fluid (or other volatile fluids, such as higher alkanes), waxes, or other oxidants that burn faster and more readily than charcoal. However, these materials penetrate only the outer surface of the charcoal. In addition, accelerants such as wax are typically distilled from a petroleum base and thus are not considered environmentally friendly. Furthermore, starting compounds typically include volatile components that are easily oxidized or are susceptible to dissipation over time, reducing the effectiveness of those fuels. Other efforts to make charcoal easier to ignite involve a mixture of charcoal and an ignitable material, ultimately forming a homogeneous material that, overall, should be easier to burn. The goal, however, of utilizing an easily ignitable material is to achieve the initial burning of the charcoal so that, once the charcoal reaches a certain level of combustion, it burns without further aid. Accordingly, mixing the ignitable component throughout the fuel adds little overall benefit because the benefits of ancillary ignitable components are superfluous once the combustion of the charcoal is underway. In addition, the use of volatile or easily combustible components throughout such fuels produces fumes during combustion, which may impart undesirable odors and flavors to food cooked using such an article. Such fumes are typically given off during the entire burning time, which is a considerable drawback.
Another consideration for combustible fuel is efficient burning. Some fuels release a large amount of heat during the initial stages of combustion, then taper off to a much lower release rate during the time appropriate for cooking. It would be more efficient, and perhaps safer, to have a fuel having a heat release rate during ignition that is intense and which then tapers off quickly upon complete ignition of the briquette. In this way, less heat generated by a fuel would be wasted in the startup process and could be utilized in the form of longer cooking times.
The present inventor has addressed many of the foregoing issues in his U.S. Pat. No. 7,022,147, the entire contents of which are hereby incorporated by reference thereto. However, there are additional areas of concern in the art that need to be addressed. In particular, so-called “instant-lighting” charcoal briquette fuels typically comprise various combinations of barium nitrate, sodium nitrate (nitrate-sort), wood charcoal, anthracite coal and a binder which act as an ignition or “accelerant” layer. These materials can produce noxious fumes during combustion that contain heavy metals, which are known to be harmful to humans and the environment. A particular hazard is the potential for transfer of heavy metals from the fumes to foods cooked over the briquettes. Similarly, after the accelerant layer has combusted, the resulting ashes of the charcoal and anthracite on the surface of the briquette are very incompact and are thus easily rendered airborne by air moving across the briquettes. The ashes may come into contact with and contaminate foods cooked over the briquettes. Airborne ashes are also a source of environmental pollution.
Heavy metals may also be present in the ashes remaining after combustion of the briquettes. Improper disposal of the ashes, such as in a landfill or by dispersion on the ground, can result in soil contamination.
Another drawback of current combustible fuels is that the accelerant layer intended to ignite the charcoal often burns violently and intensely, potentially harming persons in proximity to the briquettes when they are combusting. Yet another shortcoming of current combustible fuels is that the accelerant layer has a relatively short shelf life once exposed to air, making the briquettes expensive to package such that unused portions of an opened package can be stored for a period of time prior to use without significant degradation.
As can be seen, there is a need for a cost-effective method of producing a combustible fuel that is more compatible with food cooked thereover, is environmentally-friendly, has a relatively low fire hazard and has an extended shelf life.
A method for making a combustible fuel briquette is disclosed according to an embodiment of the present invention. A core portion of the briquette is comprised of compounded organic components and is compacted to a predetermined shaped such as, for example, a generally planar plum blossom round shape having a plurality of vents extending therethrough. The core portion is at least partially immersed in a liquefied accelerant which is also comprised of a compound of organic materials, thereby forming an accelerant portion of the briquette. The organic briquette is compatible with food cooked thereover, is environmentally-friendly, has a reduced fire hazard and has an extended shelf life.
One aspect of the present invention is a method for making a combustible fuel composition. At least one core component is granulated to a predetermined range of granule sizes. A metered portion of the granulated core component is formed into a generally planar core portion having a predetermined size and shape. A liquefied accelerant component is provided, and the core portion is at least partially immersed into the accelerant component such that the accelerant component at least one of coats the core portion and is absorbed by the core portion, thereby forming a briquette.
Another aspect of the invention is method for making a combustible fuel composition that comprises the steps of granulating a plurality of solid core components to respective predetermined ranges of granule sizes, combining the granulated solid core components together, and stirring the combined solid core components. A liquefied core component is combined together with the combined solid core components. The combined solid and liquid core components are stirred. A metered portion of the combined solid and liquid core components is formed into a generally planar core portion having a predetermined size and shape. The core portion is then dried after forming. A liquefied accelerant component is provided in an immersion tank. The core portion is transported into the immersion tank by means of a conveyor belt, at least partially immersing the core portion in the accelerant component at a predetermined depth for a predetermined soaking time such that the accelerant component at least one of coats the core portion and is absorbed by the core portion, thereby forming a briquette. The briquette is transported out of the immersion tank by means of the conveyor belt and cooled.
Further features of the inventive embodiments will become apparent to those skilled in the art to which the embodiments relate from reading the specification and claims with reference to the accompanying drawings, in which:
In the discussion that follows, like reference numerals are used to refer to like elements in the various figures.
With reference to
Briquette 10 may further include a generally centrally-located, cruciform-shaped vent 14, as well as a plurality of cylindrically-shaped vents 16 and rectangularly-shaped vents 18. Vents 14-18 extend between a top surface 20 and a bottom surface 22 of briquette 10. Vents 14-18 encourage air flow ventilation through and around briquette 10 for rapid, even burning and complete combustion, thus providing a clean, low-ash heat source. Vents 14-18 also provide for fast and generally uniform drying of briquette 10 during fabrication of the briquette, as further detailed below.
With reference to
Briquette 10 comprises a core portion 24 and an accelerant-impregnated portion 26, as shown in
Core portion 24 of briquette 10 may be formed using any conventional process including, without limitation, molding, stamping and machining. A non-limiting example molding process is shown in
To produce a briquette, molding device 40 is loaded as shown in
With reference to
The method of
With reference to
Conveyor belt 52 may be made from any material suitable for use with core portion 24 and accelerant 26. In one embodiment conveyor belt 52 is made from steel mesh material. Conveyor belt 52 is preferably a continuous or “endless loop” belt.
Immersion tank 54 may be made from any material suitable for use with accelerant 26. Immersion tank 54 is configured to heat and maintain accelerant 26 at a predetermined temperature. Immersion tank 54 may be directly heated with heating elements, or may be heated indirectly by a water hot water tank in proximity thereto. Both heating methods are well-known in the art and thus will not be detailed further.
A flow diagram showing an example process for producing briquette 10 is shown in
At steps s104a-s104c solid components 58a, 58b, 58c of core portion 24 are separately granulated, such as by crushing, using any conventional process such that the components are reduced to a granular form having a predetermined granule range of granule sizes. For wood charcoal and anthracite coal a granule size of about 100 mesh is desirable. Example processes include crushing and/or sifting the components to achieve the desired granule size. Air flow across a crushing and/or sifting process may also be utilized to aid in gathering crushed materials having small granularity.
At step s106 one or more core portion 24 liquid components, shown generally as 58d in
At steps s108a-s108c the granulated core portion components 58a, 58b, 58c of steps s104a-s104c are separately conveyed for combination in a common container or vessel, as at s110. Example conveyances include, without limitation, conveyor belts, material augers, pipes, funnels or any combination thereof. The conveyances of s108a-s108c may include pressurization, mechanical agitators and/or timed- or phased-operation of high-pressure gas jets within the conveyances to resist clumping or jamming of core portion components, thereby aiding accurate and repeatable dispensing of the core portion components in the desired amounts and proportions at step s110, below.
At step s110 core portion components 58a, 58b, 58c are metered into a common container in predetermined proportions suitable for a given application. The core portion components may be metered manually by measuring out components in the desired proportions to produce a batch of a predetermined quantity of briquettes 10. Alternatively, the core portion components may be automatically dispensed, measured and metered using conventional computer-controlled material-handling equipment and devices.
At step s112 the combined core portion 24 components 58a, 58b, 58c are stirred as needed to achieve a generally uniform or homogenous dry combination. The core portion components may be stirred together in a container by any conventional process including, without limitation, conventional agitators, beaters and paddles. In some embodiments of the present invention helix-screw augers may be used to transport the combined core portion components while simultaneously stirring them. In still other embodiments the combined core portion components may be subjected to plural parallel and/or serially staged stirring processes utilizing containers and/or augers during step s112 to ensure uniformity.
At step s114 heated and liquefied core portion component 58d is conveyed for combination with the previously-combined dry mixture of core portion components 58a, 58b, 58c to form a wet mixture 50 (
Mixture 50 may formed at s116 by any conventional process such as combining the solid combination of core portion components 58a, 58b, 58c and heated liquid core component 58d in a common container or vessel and stirring with conventional stirrers, beaters, paddles or agitators. Alternatively, core portion components 58a, 58b, 58c and heated core portion component 58d may be both combined and stirred together while being transported, such as through the use of helix-screw augers. When formed, mixture 50 (
At step s118 a core portion 24 is formed using the process of
At step s120 core portion 24 is dried by any conventional process including, without limitation, kilns or ovens incorporating any combination of heat, infra-red energy, blowing air and vacuum. Humidity controls may also utilized to control the drying of core portion 24. In one embodiment of the present invention the core portions 24 are loaded into drying trays, which are put into a kiln for drying. The kiln is preferably tunnel-shaped and typically extends approximately 40 to 50 meters. The entrance temperature of this kiln is approximately 150 degrees Centigrade, and heated air in the kiln should be provided with relatively low humidity. These conditions are maintained for about 6.5 to 7 hours, at which time the core portions 24 are removed. The exit temperature of the kiln is about 50 to 60 degrees Centigrade at a relatively high humidity.
At step s122 the components of accelerant 26 are compounded together, then heated to a predetermined temperature to achieve and sustain a liquefied state as at s124. Accelerant portion 26 has a predetermined viscosity corresponding to the desired extent to which the accelerant portion is to penetrate core portion 24 when combined therewith. A kettle (not shown) may be used to stir and heat the components of accelerant 26 to a liquid state. In one embodiment the kettle has three layers. The interior layer is made of a porcelain enamel material. The middle layer at least partially includes an oil to aid in heat conduction, and the outer layer is made of steel. The kettle may include conventional stirring paddles, beaters, agitators or similar devices to aid in mixing the components of accelerant 26.
At step s126 the dried core portion 24, which may be cool, warm or hot according to particular application, is at least partially immersed, i.e., submerged, in the liquefied accelerant 26, as depicted in
The finished briquette 10 may then packaged for storage and/or shipment. For example, one or more briquettes 10 may be encased separately or together in a protective layer, such as a plastic shrink wrap or vacuum sealing. Furthermore, a quantity of briquettes 10 may be packaged together in a container, such as a paperboard container.
In use, a group of briquettes 10 may be placed adjacent each other such that the sidewalls 12 of each briquette are proximate the sidewalls of adjacent briquettes. In one embodiment the sidewalls 12, when extrapolated, form an included angle of approximately 30 degrees. This angle permits orientation of six briquettes to define a circle about a center portion which is free of the cooking medium. The center portion of the circle formed by a group of six briquettes 10 is the optimal area for cooking. Cooking directly over the briquettes 10 subjects the barbecued item to greater heat overall, which leads to greater cooking control when using briquette of the present invention.
Accelerant portion 26 serves to ignite the core portion 24 of each briquette 10. When the accelerant portion 26 is applied in accordance with
In some embodiments of the present invention a fuse (not shown) may be joined with accelerant portion 26 to further facilitate lighting of briquette 10. One example is a fuse formed as a substantially circular disc of fibrous material and attached to accelerant portion 26, as described in applicant's U.S. Pat. No. 7,022,147 and incorporated herein by reference. Other example fuses include wicks, tabs and pads joined with accelerant portion 26 and made of a material suitable for sustaining a flame sufficient to ignite the accelerant portion.
With reference to
Briquette 90 may further include a generally centrally-located cylindrical vent 92, as well as a plurality of peripherally-located, cylindrically-shaped vents 16 and rectangularly-shaped vents 18. Vents 16, 18, 92 extend between a top surface 20 and a bottom surface 22 of briquette 90. Vents 16, 18, 92 encourage air flow ventilation through and around briquette 90 for rapid, even burning and complete combustion, thus providing a clean, low-ash heat source. Vents 16, 18, 92 also provide for fast and generally uniform drying of briquette 90 during fabrication of the briquette, as further detailed below.
With continued reference to
In some embodiments of the present invention seasoning materials may be added to briquette 10, such as a core component 58, to produce a desired aroma and/or impart flavoring to food cooked over the briquette. For example, seasoning materials may be added to briquette 10 to add a smokehouse, hickory, fruitwoods or mesquite flavoring and/or aroma. Non-limiting example seasoning materials include wood shavings or chips, resins, oils and extracts.
In still other embodiments of the present invention the proportions of the components of core portion 24 and accelerant portion 26, may be varied in order to tailor the burning characteristics of the accelerant portion in a desired manner, such as achieving a relatively fast combustion rate and/or intensity. Likewise, the proportions of the components of core portion 24 and accelerant portion 26 may be varied within the ranges specified (or even beyond the specified ranges) in order to achieve a greater or lesser amount of smoke generated by the core portion and/or the accelerant portion while combusting.
While this invention has been shown and described with respect to a detailed embodiment thereof, it will be understood by those skilled in the art that changes in form and detail thereof may be made without departing from the scope of the claims of the invention.
This application claims priority to U.S. provisional patent application No. 60/868,796, filed Dec. 6, 2006, the entire contents of which are hereby incorporated by reference thereto.
| Number | Date | Country | |
|---|---|---|---|
| 60868796 | Dec 2006 | US |
