Patent Application
20100006680
The present invention relates a process and apparatus for drying and powderizing material.
Animal byproduct meals, fecal material, agricultural fertilizer, corn byproducts, wheat byproducts, wood chips, saw dust, blood, bio-solids, milk powder, lime, coal, seaweed, and the like are high moisture content materials that may provide a rich source of energy when effectively dehydrated and powdered.
Therefore, there is a need for a process and system for drying and powderizing these materials.
An embodiment of the present invention provides an apparatus for drying and powderizing organic material. The apparatus includes at least one chamber including: an intake adapted to receive warm air and the material into the at least one chamber, and an outlet adapted to transport warm air and powder out of the at least one chamber; at least one rotatable drive shaft in the at least one chamber adapted to be rotatable; and at least one blade assembly on the at least one rotatable drive shaft. The blade assembly includes a blade hub about the at least one rotatable drive shaft and at least one blade coupled to the blade hub, wherein the at least one blade is adapted to powderize the material to expose a surface of the material to the warm air so that moisture in the material evaporates into the warm air.
The apparatus may further include at least one flat blade assembly on the at least one rotatable drive shaft, the flat blade assembly including a flat blade hub about the at least one rotatable drive shaft and at least one flat blade coupled to the flat blade hub, wherein the at least one flat blade is adapted to pre-break the material to expose a surface of the material to the warm air so that moisture in the material evaporates into the warm air. The apparatus may further include at least one fixed blade assembly on an interior wall of the at least one chamber and adjacent to the at least one flat blade, wherein the fixed blade assembly includes at least one fixed blade and is adapted to pre-break the material between the at least one flat blade and the at least one fixed blade. The apparatus may further include at least one angled blade assembly on the at least one rotatable drive shaft, the angled blade assembly including an angled blade hub about the at at least one rotatable drive shaft and at least one angled blade coupled to the angled blade hub, wherein the at least one angled blade is adapted to transport the material through the at least one chamber and powderize the material. The apparatus may further include at least one paddle assembly on the at least one rotatable drive shaft, the paddle assembly comprising a paddle hub about the at least one rotatable drive shaft and at least one paddle coupled to the paddle hub, wherein the at least one paddle is adapted to accelerate the powder and transport the powder through the outlet.
The flat blade assembly may include twelve flat blades on the flat blade hub, wherein an angle between each of the flat blades is 30 degrees. The angled blade assembly may include twelve angled blades on the angled blade hub at an angle of seven degrees to the longitudinal axis of the at least one rotatable drive shaft, wherein an angle between each of the angled blades is 30 degrees. The paddle assembly may include 8 paddles on the paddle hub, wherein an angle between each of the blades is 45 degrees.
The apparatus may further include: three flat blade assemblies on the at least one rotating drive shaft; four angled blade assemblies on the at least one rotating drive shaft; and one paddle assembly on the at least one rotating drive shaft.
The apparatus may further include a first chamber and a second chamber. The first and second chambers may be coupled so that a portion of the material passing through the intake passes into the first chamber and another portion of the material passing through the intake passes into the second chamber. The apparatus may further include a first rotatable drive shaft in the first chamber, a second rotatable drive shaft in the second chamber, at least one first blade assembly rotating in a first direction and comprising a first blade hub on the first rotatable drive shaft and at least one first blade, and at least one second blade assembly rotating in a second direction and comprising a second blade hub on the second rotatable drive shaft and at least one second blade. A portion of the at least one first blade may be adjacent a portion of the at least one second blade. A portion of the material may be transported from the first chamber to the second chamber and another portion of the material may be transported from the second chamber to the first chamber as the first and second blade assemblies rotate. The at least one first blade and at least one second blade may be adapted to pre-break the material between the at least one first blade and at least one second blade.
An outer end of the at least one blade may rotate at a velocity in a range from about 6000 feet per minute to about 11000 feet per minute.
The velocity of the warm air in the intake may be in a range from about 4000 feet per minute to about 6000 feet per minute. The velocity of the warm air at the angled blade assembly may be in a range from about 400 feet per minute to about 600 feet per minute. The velocity of the warm air at the paddle assembly may be in a range from about 4000 feet per minute to 6000 feet per minute.
The at least one chamber further comprises grinding bars on an interior wall of the chamber adapted to disrupt rotational air flow and material flow, and transport the material into a path of the at least one blade and powderize the fuel.
The grinding bars may be about ¾ inch by about ¾ inch and are spaced about one inch apart on the interior wall. The grinding bars may be at a seven degree angle to the longitudinal axis of the at least one rotatable drive shaft.
Another embodiment of the present invention provides a method for drying and powderizing material. The method includes: feeding warm air and material through an intake to at least one chamber; pre-breaking the material in the warm air by rotating at least one blade assembly on at least one rotatable drive shaft adapted to be rotated through the material, the blade assembly comprising a blade hub and at least one blade, wherein the at least one blade is adapted to pre-break the material to expose a surface of the material to the warm air so that the moisture in the material evaporates into the warm air; and transporting warm air and powder out of the at least one chamber through an outlet.
The powderizing of the material may further include: pre-breaking the material between at least one flat blade assembly and at least one fixed blade on an interior wall of the at least one chamber, wherein the flat blade assembly comprises a flat blade hub about the at least one rotatable drive shaft, and at least one flat blade adjacent to the at least one fixed blade and adapted to pre-break the material. The powderizing of the material may further include: powderizing the material and transporting the material through the at least one chamber by rotating at least one angled blade assembly through the material, wherein the at least one blade assembly comprises an angled blade hub about the at least one rotatable drive shaft and at least one rotating angled blade. The powderizing of the material may further include accelerating the material and transporting the material through the outlet by rotating at least one paddle assembly through the powder, wherein the paddle assembly comprises a paddle hub about the at least one rotatable drive shaft and at least one paddle adapted to accelerate and transport the powder.
The flat blade assembly may include twelve flat blades on the flat blade hub, wherein an angle between the blades is 30 degrees. The angled blade assembly may include twelve blades on the angled blade hub and at an angle of seven degrees to the longitudinal axis of the at least one rotatable drive shaft, wherein an angle between the blades is 30 degrees. The paddle assembly may include 8 paddles on the paddle hub, wherein an angle between the blades is 45 degrees.
Three flat blade assemblies may be on the at least one rotatable drive shaft. Four angled blade assemblies may be on the at least one rotatable drive shaft. One paddle assembly may be on the at least one rotatable drive shaft.
The at least one chamber may include a first chamber and a second chamber, wherein the first and second chambers are coupled so that a portion of the material passing through the intake passes into the first chamber and another portion of the material passing through the intake passes into the second chamber, a first rotatable drive shaft in the first chamber; a second rotatable drive shaft in the second chamber; at least one first blade assembly rotating in a first direction and comprising a first blade hub on the first rotatable drive shaft and at least one first blade; at least one second blade assembly rotating in a second direction and comprising a second blade hub on the second rotatable drive shaft and at least one second blade, wherein a portion of the at least one first blade is adjacent a portion of the at least one second blade, wherein a portion of the material is transported from the first chamber to the second chamber and another portion of the material is transported from the second chamber to the first chamber as the first and second rotating blade assemblies rotate, and wherein the at least one first and second blades are adapted to pre-break the material between the at least one first and second blades.
The detailed description set forth below in connection with the drawings is intended as a description of embodiments of a process and apparatus for drying and powderizing material in accordance with the present invention and is not intended to represent the only forms in which the invention may be constructed or utilized. It is to be understood that the same or equivalent functions and structures may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention. As denoted elsewhere herein, like element numbers indicate like elements or features.
Some biological or organic waste materials, such as animal byproduct meals, fecal material, agricultural fertilizer, corn byproducts, wheat byproducts, wood chips, saw dust, blood, bio-solids, milk powder, lime, coal, seaweed, are a rich source of energy when they are in a dry state. However, animal meal contains a high level of moisture. Further, sewage is transported in water and this water must be removed by pressing the sewage, and the solids that remain after the pressing still contain about 70% to about 80% moisture and about 20% solids by weight. Corn byproducts, wheat byproducts, and wood pulp are other examples of materials that are a good source of energy but generally contain too much moisture to be useable as fuel in their raw state. These materials (or raw fuel) must be dried to about 5% moisture to be a high grade fuel. A large quantity of high temperature air is required to evaporate the moisture from the material.
A process for converting the moisture-laden material into dry powder according to an embodiment of the present invention includes breaking the material into powder in the presence of warm fresh air so that moisture in the material quickly evaporates into the warm fresh air.
According to an embodiment of the present invention as shown in
In an embodiment of the present invention, the material is fed into the apparatus with a center-less auger at a rate of about 9 cubic feet per minute to about 12 cubic feet per minute.
In an embodiment of the present invention, warm fresh air is fed into the apparatus at a rate of about 9,000 cubic feet per minute. However, one of ordinary skill in the art will appreciate that the apparatus may be optimized for different desired rates of processing material, and that the flow rate of the warm fresh air may be adjusted accordingly.
Inside the chamber 10, at least one rotating blade assembly (22 or 28) breaks the material into a powder (e.g., pre-break and/or powderize the material). For example, the material may be broken into a powder with a consistency resembling talcum powder.
The blade assembly (22 or 28) includes at least one blade (26 or 32) and a blade hub (24 or 30), where the blade hub (24 or 30) is mounted on a drive shaft 16, which may be hollow or solid stock mild steel or any other suitable material, rotated by a motor 18.
In an embodiment of the present invention, the drive shaft 16 has a diameter of about 2 inches to about 6 inches.
In an embodiment of the present invention, the chamber 10 is sealed about the drive shaft 16 so that material and air do not escape from the chamber.
In an embodiment of the present invention, the apparatus includes at least one flat blade assembly 22 and at least one angled blade assembly 28. As shown in
In an embodiment of the present invention shown in
In an embodiment of the present invention, the outer tips of the blades 26, 32 are moving at about 6000 feet per minute to about 11000 feet per minute.
In an embodiment of the present invention, the air passing through the angled blades 32 has a velocity of about 400 feet per minute to about 600 feet per minute.
In an embodiment of the present invention as shown in
In an embodiment of the present invention, the air passing through the paddles 38 has a velocity of about 4000 feet per minute to about 6000 feet per minute.
In an embodiment of the present invention shown in
In an embodiment of the present invention, the fixed blade 42 includes two sections that are attached to each other at a 57 degree angle. In an embodiment of the present invention, the fixed blades, forming two sides of the triangular formation, are about 40 mm wide and 25 mm thick.
In an embodiment of the present invention shown in
In an embodiment of the present invention, the grinding bars 112 are positioned along the interior wall of the chamber 10 at an angle of about seven degrees to the longitudinal axis of the drive shaft 16.
In an embodiment of the present invention, the distance between the grinding bars 112 and the tips of the blades 26, 32 is about 30 mm.
In an embodiment of the present invention, the grinding bars 112 promote warm air movement in an axial direction and discourage rotational circulation through the chamber 10. Here, because both the grinding bars 112 and the angled blades 32 are set at the same angle of seven degrees, the discharge from the tip of each of the angled blades 32 will follow the taper of the grinding bars, which will prevent or reduce build up of material on the interior walls of the chamber 10.
In an embodiment of the present invention, there are two chambers 10 that are in communication with each other. Each chamber has a drive shaft with rotating blade assemblies 22, 28 and/or a paddle assembly 34. Here, the inlet 12 allows material to be fed into both chambers 10 at the same time, so that some of the material falls into one chamber and some of the material falls into the other chamber. Further, as the rotating blades 26, 32 shear and move the material, portions of the material move from one chamber to the other.
In an embodiment of the present invention, the first rotating blade assemblies 22, 28 on a drive shaft 16 in a first chamber 10 rotate in one direction, e.g., clockwise, and second rotating blade assemblies 22, 28 on a drive shaft 16 in the other second chamber 10 rotate in a second direction, e.g., counterclockwise, opposite the first direction.
In an embodiment of the present invention, the material is exposed to a double axial and radial motion within the turbulence created between the communicating chambers 10.
In an embodiment of the present invention, portions of the first and second rotating blade assemblies 22, 28 rotate past each other so that the material is sheared and powderized between the first and second rotating blade assemblies 22, 28 and material moves between the first and second chambers 10.
In an embodiment of the present invention, the surface area of the powder is about 3000 times the surface area of the material as it enters the apparatus. The increase in surface area varies with the type of material being processed, thus air flow and temperatures are adjusted accordingly.
In an embodiment of the present invention, the warm air in the apparatus may contain contaminants from the material, such as pathogens and the like, and should be contained to prevent escape to the atmosphere. Here, the apparatus is sealed so that the contaminated warm air does not escape to atmosphere. Warm fresh air is blown into the inlet 12, which prevents or reduces contaminated air from traveling to the atmosphere through the inlet 12. Further, the outlet 11 may be sealed to a conduit that either contains the contaminated air or transports the contaminated air to another apparatus so that the contaminated air may be treated.
In an embodiment of the present invention, the material moves through the apparatus in about 15 seconds.
In an embodiment of the present invention where the material is sewage, the powder from the apparatus combusts at about 1100 degrees C. Once the powder is combusted, the ash left behind is basically sand, which may be utilized for landscaping or making glass or bricks.
For example, the composition of the sand was experimentally found to be as follows:
In an embodiment of the present invention where the material is sewage, the volume of the sewage is reduced to about 3% to 7% of the original volume.
In an embodiment of the present invention, the powder and warm air passes from the apparatus to a filter so that the powder is filtered from the warm air.
In an embodiment of the present invention, a heat dissipater (or heat slinger) is attached to the drive shaft 16 so that excess heat from the drive shaft 16 is discharged to the atmosphere.
In an embodiment of the present invention, the acceleration of the warm air and the powder through the apparatus reduces the pressure loss across the apparatus by 60%.
In the apparatus, the material is broken into a powder that resembles talcum powder. For example, the particles of the powder may be a size where about 80% of the particles will be smaller than 76 microns (or 200 mesh). This breaking of the material takes place in the presence of the warm fresh air so that the moisture in the material evaporates into the warm fresh air as the material is broken into powder. In an embodiment of the present invention, powder leaving the apparatus has about 3% to 7% moisture.
Although the present invention has been described through the use of exemplary embodiments, it will be appreciated by those of skill in the art that various modifications may be made to the described embodiments that fall within the scope and spirit of the invention as defined by the claims and their equivalents appended hereto. For example, aspects shown above with particular embodiments may be combined with or incorporated into other embodiments.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 61/080,466, filed on Jul. 14, 2008, in the United States Patent and Trademark Office, the entire content of which is incorporated herein by reference. The entire content of U.S. patent applications ENERGY RECOVERY AND TRANSFER SYSTEM AND PROCESS (Attorney Docket No: T643-63990; application Ser. No. ______), HEAT RECOVERY AND PRESSURE CONTROL UNIT (Attorney Docket No: T643-64004; application Ser. No. ______), and METHOD AND APPARATUS FOR STERILIZING AND DEODORIZING AIR (Attorney Docket No: T643-64005; application Ser. No. ______) filed on Jul. 14, 2009 in the United States Patent and Trademark Office is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61080466 | Jul 2008 | US |
