This patent is directed to methods and systems for solid waste processing, and, in particular, to methods and systems for solid waste processing utilizing vibratory equipment with mixed solid waste material.
According to an aspect of the present disclosure, a vibratory system for processing solid waste material includes a storage conveyor including a trough with a deck and opposing side walls disposed to either side of the deck, a plurality of resilient members supporting the trough above a surface, and a vibration generator coupled to the trough to move solid waste material disposed in the trough along the deck to an outlet. The system also includes a heating unit including a container with an opening to receive solid waste material from the outlet of the storage conveyor, the opening being in communication with an interior chamber, a closure moveable relative to the opening to limit passage of solid waste material through the opening, and a source of steam coupled to the interior chamber to provide steam to the interior chamber to heat solid waste material disposed therein.
According to another aspect of the present disclosure, a method of processing solid waste material includes storing solid waste material in a storage conveyor, the conveyor including a trough with a deck and opposing side walls disposed to either side of the deck, a plurality of resilient members supporting the trough above a surface, and a vibration generator coupled to the trough to move solid waste material stored in the trough along the deck to an outlet. The method also includes activating the vibration generator to move the solid waste material along the deck to the outlet, receiving the solid waste material in a container, and supplying steam to the container to heat the solid waste material received therein to generate treated solid waste material.
Although the following text sets forth a detailed description of different embodiments of the invention, it should be understood that the legal scope of the invention is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment of the invention since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims defining the invention.
It should also be understood that, unless a term is expressly defined in this patent using the sentence “As used herein, the term ‘______’ is hereby defined to mean . . . ” or a similar sentence, there is no intent to limit the meaning of that term, either expressly or by implication, beyond its plain or ordinary meaning, and such term should not be interpreted to be limited in scope based on any statement made in any section of this patent (other than the language of the claims). To the extent that any term recited in the claims at the end of this patent is referred to in this patent in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term be limited, by implication or otherwise, to that single meaning. Finally, unless a claim element is defined by reciting the word “means” and a function without the recital of any structure, it is not intended that the scope of any claim element be interpreted based on the application of 35 U.S.C. §112, sixth paragraph.
Referring first to
Starting then at the left-hand side of
A transport device (not shown) may be disposed in the space 102 to load the solid waste materials of the piles 104, 106, 108 into the system 100. Such a transport device may take the form of a vehicle, such as a front loader, for example. Alternatively, the transport device may be in the form of an overhead crane fitted with a claw, a bucket or the like. Still further, the transport device may include a conveyor on which workers manually dispose the solid waste material for its transit along the conveyor into the system 100.
The system 100 includes at least one storage conveyor 120. Four storage conveyors 120 are illustrated in
Referring now to
According to the illustrated embodiment, the frame 152 is required to provide a certain elevation for the solid waste material relative to other elements of the system 100, such as the heating unit 130. The size of the frame 152 is also dictated, in part, by the relative elevations of the surfaces on which the different elements of the system 100 are supported. It will be recognized that variations in elevation of the elements and surfaces will influence the construction of the system 100 in general, and of the frame 152 in particular.
It will also be recognized that considerable variation may occur relative to the suspension of the trough 140 relative to the surface on which it is supported, and in regard to the vibration generator 154. That is, the resilient members 146 are typically paired with rigid linkages to support the trough 140, as illustrated. The vibration generator 154 may be a two-mass system or may be a one-mass (or brute force) system. The vibration generator 154 may be coupled to the trough 140, or may be mounted on a counterpoise which may be attached to the trough 140. All of these elements may vary according the demands placed on the system 100.
Importantly, the storage conveyor 120 provides the afore-mentioned trough 140 with continuous deck 142 flanked by opposing side walls 144. The trough 140 may even include an end wall 160 at the end of the deck 142 opposite the outlet 156. The deck 142, side walls 144 and end wall 160 thus define a space 162 (see
This is to be contrasted with a belt conveyor, wherein clearance typically exists between the belt and any side walls that may be provided to guide the solid waste material along the conveyor. Solid waste materials may pass through the clearance between the belt and the side walls, if any, and become disposed in a space that may be extremely difficult to clean regularly and/or completely. Where the solid waste material includes food and other biomaterials, the material trapped in this space may provide encourage an increase in the number of insects, rodents and the like. This may result in an extremely unhealthy environment in which to work.
Thus, it will be recognized that by providing a vibratory conveyor 120, wherein the solid waste material is contained in the enclosed space 162 from which passage is restricted, the problems presented through the use of a belt or similar type of conveyor may be reduced or eliminated. Solid waste material does not end up being lost into the working gear of the conveyor 120, as the deck 142 and side walls 144 are joined together to prevent materials from passing therebetween. Consequently, the solid waste material is contained in spaces, such as space 162, that are relatively simple to clean regularly and completely. As a further consequence, insect and rodent contact with the solid waste material prior to heating may be limited.
As noted above, the system 100 also includes at least one heating unit 130. In fact, as noted above, the system 100 includes four heating units 130. It will be recognized that the number of heating units 130 illustrated is non-limiting; a greater number or a lesser number of heating units 130 may be included.
As seen in
As seen in
The steam is released into the interior chamber 174 after first evacuating the air from the chamber 174. Pressures within the container 170 may exceed 50 psi during the heat treatment in the chamber 174. Furthermore, temperatures within the container 170 may exceed 500° Fahrenheit during this time. Consequently, the container 170 must be able to withstand such pressures and temperatures.
The container 170, or a portion thereof, may rotate about an axis. For example, a drum may be disposed within the chamber 174 for rotation about its longitudinal axis, which axis may be aligned with the longitudinal axis of the container 170. The interior surface of this drum may have angular or helical surfaces to provide proper agitation of the solid waste material in the chamber 174 during processing. For that matter, the rotation of the inner drum may facilitate movement of the solid waste materials into and out of the container 170 before and after processing. In this regard, the container 170 may have a structure and operation similar to the ROTOCLAVE® rotating autoclave system available from Tempico Inc. of Hammond, La.
To move the material from the storage conveyor 120 to the heating unit 130, a feed conveyor 190 may be provided. The feed conveyor 190 may be disposed between the outlet 156 of the storage conveyor 120 and the opening 172 of the container 170 to bridge a space 192 between the outlet 156 and opening 172. The space 192 may be provided, for example, to permit clearance for the door 174 to close over the opening 172. The space 192 may also permit clearance for treated solid waste materials to be ejected from the container 170 on to a different conveyor or transport system for transport away from the heating units 130.
The feed conveyor 190 may be similar in structure and operation to the storage conveyor 120, with certain differences to provide mobility. The feed conveyor 190 may include a trough 194 with a deck 196 and opposing side walls 198 disposed to either side of the deck 196. A moveable frame 200 is provided, the frame 200 having a first position (
In operation, the feed conveyor 190 would be maintained in the position illustrated in
The discharge conveyor 220 is the first in a series of conveyors that may define one or more transfer systems. In this regard, a transfer system may include a single conveyor, or a plurality of conveyors. A transfer system may couple various processing devices of the system 100 together through these conveyors alone, or in combination with other elements of the system 100. In fact, the processing devices may themselves define, in whole or in part, a transfer system. For that matter, the conveyors 120, 190 and the heating unit 130 may define one or more transfer systems depending on the perspective of the element of the system 100 under discussion.
As illustrated in
The inclined belt conveyor 230 transports the treated solid waste material to the inlet end 240 of a first of a pair of screening conveyors 242, 244 (see
Each of the screening conveyors 242, 244 has a similar structure and operation. For example, referring to the screening conveyor 242, the conveyor 242 includes a screening conveyor trough 246 with a foraminous deck 248 and opposing side walls 250 disposed to either side of the deck 248. In fact, the sides 250 are coupled to the bottom 252 of the trough 246 so that material that passes through the deck 248 collects on the bottom 252 of the trough 242. The deck 248 may be defined by one or more conventional finger screens 254. A plurality of resilient members 256 supporting the trough 246 above a surface.
A vibration generator 258 is coupled to the trough 246 to move materials along the deck 248 and the bottom 252 of the trough 246. In particular, larger treated solid waste materials move along the deck 248 to an outlet 260. On the other hand, smaller treated solid waste materials pass through the deck 248, along the bottom 252 and to an outlet 262. In this fashion, the treated solid waste material is sorted according to physical size.
The materials passing through the outlet 260 are directed onto a deck 270 of the screening conveyor 244, which deck may be defined by one or more finger screens 272. Similar to the structure and operation of the conveyor 244, the larger treated solid waste materials move along the deck 270 while the smaller treated solid waste materials pass through the deck 270 and are collected on a bottom 274 of a trough 276. The materials moving along the deck 270 are directed to an outlet 278, while the materials moving along the bottom 272 are directed to an outlet 280.
It will be recognized that by selecting the size of the finger screens 254, 272 that define the foraminous decks 248, 270, three differently sized streams of treated solid waste material may be generated at outlets 262, 278, 280. Each of these streams is carried by a separate transfer system to a different part of the system 100 for further processing. Each of the transfer systems includes at least one belt conveyor 282, 284, 286, which conveyors are shown in part in
The treated solid waste stream with the smallest relative physical size passes through outlet 262 and along conveyor 282 to a press 300; as illustrated, the treated solid waste material may pass to one of two presses 300 that are arranged to processes the material in parallel. The press 300 is the first of two different processing devices in the system 100 that may be used to remove moisture from the treated solid waste material to generate dried, treated solid waste material. As seen in
The press 300 may be a screw press, such as is illustrated in
The inner structure of the screw press is shown in greater detail in
Coupled to the outlet 308 of the press 300 is a further transfer system, in this case including a belt conveyor 340 as shown in
The dryer 352 may be a conventional fluid bed dryer. The dryer 352 illustrated has the advantage of drying the treated solid waste material entering via the inlet 350 and moving the solid waste material from the inlet 350 to the outlet 354. In this regard, the dryer 352 may have a structure similar to the screening conveyors 342, 344, in that the dryer 352 may include a trough 360 with a deck 362 and opposing side walls 364 disposed on either side of the deck 362. An air plenum 366 is defined beneath the deck 362 to receive heated air therein from a source of heated air 368. The deck 362 has a plurality of openings therein to permit heated air from the plenum 366 to pass through the deck 362 and the material disposed above the deck 362. A plurality of resilient members 370 supports the trough 360 above a surface. A vibration generator 372 is coupled to the trough 360 to move materials along the deck 362.
The dried, treated solid waste material exiting dryers 352 via the respective outlets 354 is carried by a transfer system to a densifying and pelletizing apparatus 380. The transfer system may include several different devices for further sorting the dried treated solid waste material prior to its delivery to the densifying and pelletizing apparatus 380. The input of the transfer system is coupled to the outlet of the dryer 352 and the outlet of the transfer system is coupled to the inlet of the densifying and pelletizing apparatus 380.
The transfer system includes a first belt conveyor 390 is coupled to the outlets 354 of the dryers 352. An overhead belt magnet 392 is disposed at the output end of the belt conveyor 390 to attract and remove any metallic solid waste materials that may have been conveyed to this section of the system 100. The materials not removed by the belt magnet 392 are passed from the output end of the belt conveyor 390 to an input end of a second belt conveyor 394 with its output end coupled to the input end of a high-stroke feeder 396. The output end of the high-stroke feeder 396 may be coupled to the input end of a separation apparatus 398, such as a gear sorter. The output end of the separation apparatus 398 may be coupled in turn to further belt conveyor 400, which passes the dried, treated solid waste materials to dryer and cyclone separator 402, the output of which is coupled to the densifier and pelletizing apparatus 380. The pelletized, dried, treated solid waste material may then be transported to be used as fuel, for example.
Referring next to
As illustrated in
As illustrated in
It is believed that the present disclosure may have several benefits, one or more of which may be present in a particular embodiment according to the present disclosure.
This application claims the benefit of U.S. Application No. 61/034,337, filed Mar. 6, 2008, which is hereby incorporated by reference in its entirety in the present application.
Number | Date | Country | |
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61034337 | Mar 2008 | US |