This invention relates to a dross compression apparatus and more particularly to a cooling system and cooling method for more effectively cooling the compression head of a dross compression apparatus.
Dross compression apparatus are commonly used to recover non-ferrous metals, particularly aluminum, from dross which has been skimmed from a furnace. Aluminum dross is a combination of aluminum metal and aluminum oxides, as well as other possible components such as various oxides, nitrates and carbides. Aluminum dross is a by-product of an aluminum melting operation. Generally the dross floats on top of the molten aluminum metal in the furnace. Aluminum dross may contain anywhere from ten percent to ninety percent aluminum depending on the particular processing technique and the type of furnace. Therefore the dross in an aluminum melting operation includes a significant amount of aluminum metal which is considered a valuable resource to be recovered.
The recovery of aluminum from aluminum dross must also address the problem of the loss of aluminum metal in the dross due to thermiting or thermite reaction, i.e., exothermic oxidation of aluminum metal. It is generally known to provide the compression head of the dross compression apparatus with air or water cooling to reduce the thermiting action and thereby increase the amount of aluminum recovered from the aluminum dross. However, there is a continuing need to be able to remove heat more effectively from the dross compression head to increase the capacity of the dross compression apparatus in recovering aluminum from aluminum dross or other non-ferrous metals from other drosses without the use of water cooling.
The compression head of the dross compression apparatus is more effectively cooled in accordance with the present invention by blowing cooling air across the top of the compression head during the recovery of various non-ferrous metals including aluminum from various types of dross.
In accordance with one aspect of the invention, one or more air nozzles are provided for directing cooling air across the top of the compression head.
In accordance with another aspect of the invention, one or more air vents are provided in the dross compression apparatus for venting the air after being directed across the top of the compression head.
In accordance with another aspect of the invention, a plurality of ribs may extend across the top of the compression head in the direction of the air vents for directing the air out of the air vents after being directed across the top of the compression head.
In accordance with another aspect of the invention, the air nozzles may direct air along and between the ribs on the top of the compression head toward the air vents.
In accordance with another aspect of the invention, the air nozzles may be movable in synchronism with the compression head during vertical movement of the compression head toward and away from the dross collector.
These and other objects, advantages, features and aspects of the present invention will become apparent as the following description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which the principles of the invention may be employed.
In the annexed drawings:
Referring now in detail to the drawings wherein like reference numerals are used to indicate like parts, and initially to
Dross collector 4 may have a substantially hemispheric shaped receptacle 5 and compression head 2 may be similarly shaped to cooperate with the receptacle. The term substantially hemispheric shaped as used herein is broadly defined to mean any shape that is substantially similar in concept and function to the shapes shown in the drawings and includes shapes that deviate from the shapes shown such as flatter structures or more pointed structures as well as structures that may have additional curved surfaces.
The dross collector receptacle 5 is provided with one or more openings (not shown) at the bottom of the receptacle to allow molten aluminum (or other molten metal) to pass by gravity and under the pressure of compression head 2 out from the collector into a lower receptacle 6 which is referred to in the art as a sow mold. Dross collector 4 may be provided with tubular members 7 for receipt of the forks of a forklift truck for transporting the dross collector 4 from a furnace to the dross compression apparatus and removal therefrom.
The compression head 2 of the present invention may be made of any suitable solid metal such as cast alloy steel to provide sufficient mass for dissipating heat in the dross metal during the recovery of various non-ferrous metals from various types of dross, including particularly aluminum from dross which has been skimmed from a furnace. Multiple ribs 10-12 may be provided on the top 15, bottom 16 and sides 17 of the compression head as schematically shown in
The ribs 11 and 12 on the bottom 16 and sides 17 of compression head 2 extend into the dross in the dross collector or skim box 4 during the recovery process to help dissipate the heat in the dross metal. Also such ribs may help increase the compressive force on the dross metal as disclosed in the aforementioned U.S. Pat. Nos. 5,397,104 and 5,669,957.
The ribs 10 on the top 15 of compression head 2 also help to remove heat from the compression head. To remove heat more effectively from the compression head, cooling air may be blown across the top of the compression head during and between relative vertical movements of the compression head and dross collector toward and away from each other. These ribs 10 extend generally in the same direction, for example, from the front of the apparatus toward the back, to help channel cooling air that is blown across the top of compression head 2 out through air vent slots 18 (see
Cooling air may be directed along the peaks 20 and valleys 21 of ribs 10 by a plurality of vortex nozzles 22 supported by an air manifold 23. If the compression head is mounted for vertical movement, the air manifold 23 and associated air nozzles 22 may be raised and lowered in synchronism with the raising and lowering of the compression head 2 so that the air is always directed across the top of the compression head and not onto the dross metal which would cause the dross metal to oxidize.
Suitable slides or the like (not shown) may be provided on the air manifold 23 for engagement with vertical rails or the like on the frame of the dross compression apparatus for guiding the air manifold during its vertical movement. Also a suitable mechanism such as a piston/cylinder 25 that is used to move the air manifold 23 vertically may be controlled by the same controller 26 (see
Suitable hoses 30 may connect the air nozzles 22 to the plenum chamber 31 of the air manifold 23 as schematically shown in
The number, size and location of the air vent slots 18 in wall 19 of dross compression apparatus 1 should be such that substantially all of the cooling air passing over the top of the compression head is discharged through the slots to minimize oxidation of the dross metal. Air vent slots 18 may all be of about the same length and may match the peaks 20 and valleys 21 formed by the ribs 10 on the top of compression head 2 in number and location. If the wall 19 of dross compression apparatus 1 in which the slots are provided contains a small door 35 used to provide access for cleaning the compression head, the slots 18 may also extend through portions of the door as schematically shown in
In operation in accordance with the method of the present invention, dross is collected from an electric furnace or the like in the receptacle 5 of the dross collector 4 and then transported to the dross compression apparatus 1. With the lower receptacle or sow mold 6 in place, metal, particularly aluminum, is allowed to decant through an opening in the lower end of the dross collector 4 into the sow mold. Then, after the main door 36 (see
The cooling air that is directed by the vortex nozzles 22 across the top of the compression head 2 during compression of the dross will lower the temperature of the compression head and maximize the cooling effect of the air on the compression head. Removing the heat from the compression head while the compression head is compressing the dross material during the recovery process increases the capacity of the dross compression apparatus without the need for water cooling. The cooling capacity of the compression head of the present invention may be as much as four times that of a standard compression head. For example, a dross compression apparatus incorporating the compression head cooling system of the present invention that normally presses three to four containers of dross metal every three to four hours would be able to press three to four containers of the dross metal every hour.
With reference to
The cooling system 37 includes a cooling head 38. The cooling head 38 may be placed on a material container 39. The cooling head 38 and material container 39 have corresponding geometries to cooperate with one another in the manners described herein. Depending on the application, the material container 39 may be referred to as a dross collector (e.g., the dross collector 4 of
The material container 39 may have a receptacle 40 for the material to be cooled. In the embodiment of
In some configurations, the material container 39 may be provided with one or more openings 41 (best shown in
The material container 39 and/or the collector pan 42 may include passages 43 that accept forks of a forklift truck for transporting the material container 39 and/or collector pan 42. In one embodiment, the cooling head 38 may include tubular members 44 for receipt of the forks of a forklift truck for transporting the cooling head 38 and/or positioning the cooling head 38 on the material container 39. In another embodiment, the cooling head 38 may be wider than the material container 39 and the forks of the forklift truck may move and/or position the cooling head 38 by engaging portions of the cooling head 38 that overhand the material container 39. In yet other embodiments, the cooling head 38 may be moved and/or positioned with respect to the material container 39 using a hoist or crane. The cooling head 38 may include a hook(s), ring(s) or other member for facilitating coupling of the cooling head 38 to the hoist or crane by way of, for example, a rigid member, a cable, a chain, a hook, and so forth. In one embodiment, such as the embodiment shown in
The cooling head 38 may have a downwardly projecting protrusion 47. As illustrated, a plate-like member that forms an upper portion 48 of the cooling head 38 has a depression, or well, that forms the protrusion 47 by protruding downwardly for making thermal contact with the material. The upper surface of the upper portion 48 may be depressed so that the lower surface of the protrusion 47 is convexly curved and is disposed below the surrounding flange-like members formed by the upper portion 48. In some embodiments, the protrusion 47 may be substantially hemispheric shaped. When the cooling head 38 is positioned on the material container 39, the protrusion 47 may enter the receptacle 40 though an open top of the material container 39 and the protrusion 47 may contact the material contained in the material container 39. The cooling head 38 may include multiple protrusions 47, such as a protrusion 47 for each receptacle 40 of a multi-receptacle 40 material container 39 (e.g., the cooling head 38 and the material container 39 of
Heat from material contained in the material container 39 may be transferred to the protrusion 47. A substantial amount of the transferred heat may be conveyed to the upper portion 48 of the cooling head 38. In one embodiment, the upper portion 48 of the cooling head 38 may be a plate that surrounds the protrusion 47. In the illustrated embodiments, the upper portion 48 is open so that a recess formed by the protrusion 47 is open to the environment. This open recess, or well, creates surface area for efficient heat transfer and provides a lighter cooling head 38 relative to a cooling head 38 that has a solid protrusion 47 or a covered protrusion 47. The surface of the well (which is the upper surface of the protrusion 47) may be relatively smooth as shown or have structural elements (e.g., ribs).
The lower surface of the protrusion 47 may be relatively smooth as shown in
To assist in dissipating and/or radiating heat from the material to the environment, the cooling head 38 may include structural elements on the upper surface of the upper portion 48. For instance a series of ribs 50 may be present. The tubular member 44, if present, also may serve to assist in dissipating and/or radiating heat. In effect, the ribs 50 and/or other elements on the top of the cooling head 38 may help to remove heat from the cooling head 28. To enhance the removal of heat from the cooling head 38, cooling air may be directed across the top of the cooling head 38. For instance, as shown in
The ribs 50 on the cooling head 38 may extend generally in the same direction, such as from the front of the cooling head 38 toward the back of the cooling head 38 (e.g., as shown in
A lower surface of upper portion 48 may be configured to engage an upper edge of material container 39. The interface (or closure) between the cooling head 38 and material container 39 may reduce the flow of gasses into the receptacle and reduce oxidation of the material in the material container 39 during cooling. As indicated, edge portions of the upper portion 48 may overhang the material container 39. Overhanging portions 55 may be bent downward to enhance the sealing effect, to divert air flow and/or to provide a lip to assist in stabilizing the cooling head 38 in embodiments where a forklift is used to lift the underside of the cooling head 38. The downwardly bend overhanging portions 55 may be present on any combination of the front edge, the rear edge, the left side edge and the right side edge.
The well formed by the protrusion 47 may be filled with a material to assist in weighting the cooling head 38 and/or adjusting the cooling behavior of the cooling head 38. For instance, sand, metal shot, plates or a conforming metal insert may be placed in the well. Also, a cooling apparatus may be placed in the well. In other embodiments a coolant (in addition to or instead of the above-described air) may be directed across the surface of the recess and/or the ribs 50. For instance, water or oil may be circulated with respect to the cooling head 38.
In an exemplary industrial application to process aluminum dross, a compression apparatus (e.g., the compression apparatus 1) may be used to compress dross in a time period of about an hour or less. Then, the container in which the dross was compressed may be moved from the compression apparatus and a cooling head (e.g., the cooling head 38) may be placed on the moved dross and dross container to further cool the dross for a period of time, such as about one hour to about two hours. This allows for increased use of the compression apparatus for compression, which leads to increased throughput and process efficiencies.
Although the invention has been shown and described with respect to certain embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of the specification. In particular, with regard to the various functions performed by the above described components, the terms (including any reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed component which performs the function in the herein illustrated exemplary embodiments of the invention. Also, all of the disclosed functions may be computerized and automated as desired. In addition, while a particular feature of the invention may have been disclosed with respect to only one embodiment, such feature may be combined with one or more other features as may be desired and advantageous for any given or particular application.
This application is a continuation-in-part of U.S. patent application Ser. No. 10/778,456, filed Feb. 13, 2004, which claims the benefit of U.S. Provisional Application Ser. No. 60/518,547, filed Nov. 7, 2003, the disclosures of which are herein incorporated by reference in their entireties.
Number | Date | Country | |
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60518547 | Nov 2003 | US |
Number | Date | Country | |
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Parent | 10778456 | Feb 2004 | US |
Child | 11617052 | Dec 2006 | US |