BRINE SOLUTION CLEANING SYSTEMS, APPARATUSES, AND METHODS

Abstract

Systems, apparatuses, and methods for cleaning brine solution are provided. In particular, one or more embodiments comprise a brine cleaning system that includes a brine cooker, a brine filter, and a brine storage unit. The brine cooker heats a dirty brine solution to separate the dirty brine solution into a liquid portion and a solids portion. The brine filter is coupled to the brine cooker to receive the liquid portion and the solids portion from the brine cooker and then substantially remove the solids portion. The brine storage unit is coupled to the brine filter to accumulate the liquid portion once the solids portion have been substantially removed by the brine filter. This allows for more efficient and environmentally friendly use of brine solution in the curing of animal.

Claims

1. A brine cleaning system comprising: a brine cooker that heats a dirty brine solution; a brine filter that cleans the dirty brine solution to create a cleaned brine solution; and a brine storage unit that accumulates the cleaned brine solution.

2. The system as recited in claim 1, further comprising an incline that provides at least a portion of the dirty brine solution from the brine cooker to the brine filter down the incline.

3. The system as recited in claim 1, further comprising a brine curing hide vat that creates the dirty brine solution provided to the brine cooker.

4. The system as recited in claim 3, further comprising one or more pipes that couple the brine curing hide vat to the brine cooker.

5. The system as recited in claim 1, further comprising an evaporator and salt concentrator that recycles the cleaned brine solution.

6. The system as recited in claim 5, further comprising one or more pipes that couple the brine storage unit to the evaporator and salt concentrator.

7. The system as recited in claim 1, further comprising: a first pipe that couples the brine cooker to the brine filter to provide at least a first portion of the dirty brine solution from the brine cooker to the brine filter; and a second pipe that couples the brine cooker to the brine filter to provide at least a second portion of the dirty brine solution from the brine cooker to the brine filter.

8. A brine cleaning system comprising: a brine cooker that heats a dirty brine solution, the brine cooker comprising: a brine container; and a heating element; a brine filter that cleans the dirty brine solution to create a cleaned brine solution, the brine filter comprising: a first filter; a second filter after the first filter; and a third filter after the second filter; and a brine storage unit that accumulates the cleaned brine solution.

9. The system as recited in claim 8, wherein the brine container comprises a cavity formed by an inner wall of the brine container and an outer wall of the brine container.

10. The system as recited in claim 8, wherein the heating element comprises a sparging tube.

11. The system as recited in claim 8, wherein the heating element comprises one of a cable heater, a cartridge heater, a ceramic fiber heater, a flexible heater, a strip heater, a tubular heater, or an immersion heater.

12. The system as recited in claim 8, further comprising a pump that provides the dirty brine solution from the second filter to the third filter.

13. The system as recited in claim 8, further comprising: a solids outlet coupled to the brine filter; and a liquid outlet coupled to the brine filter.

14. The system as recited in claim 8, wherein the first filter has a first fineness, the second filter has a second fineness, and the third filter has a third fineness, such that the first fineness is less than or equal to the second fineness and the second fineness is less than or equal to the third fineness.

15. A method of cleaning brine, the method comprising: separating solids within a dirty brine solution by heating the dirty brine solution to cause the solids to coagulate; removing additional solids from the dirty brine solution to create a cleaned brine solution; and accumulating the cleaned brine solution.

16. The method as recited in claim 15, wherein separating solids within a dirty brine solution by heating the dirty brine solution to cause the solids to coagulate further comprises capturing coagulated solids within the dirty brine solution.

17. The method as recited in claim 15, wherein separating solids within a dirty brine solution by heating the dirty brine solution to cause the solids to coagulate comprises heating the dirty brine solution at 212 degrees Fahrenheit for 10 minutes.

18. The method as recited in claim 15, wherein removing additional solids from the dirty brine solution to create a cleaned brine solution further comprises filtering the additional solids from the dirty brine solution.

19. The method as recited in claim 18, wherein filtering the additional solids from the dirty brine solution comprises: applying a first filter having a first fineness to the dirty brine solution; applying a second filter having a second fineness to the dirty brine solution; and applying a third filter having a third fineness to the dirty brine solution to output the cleaned brine solution from the third filter.

20. The method as recited in claim 19: wherein applying a first filter having a first fineness to the dirty brine solution further comprises extracting solids larger than the first fineness from the dirty brine solution; wherein applying a second filter having a second fineness to the dirty brine solution further comprises extracting solids larger than the second fineness from the dirty brine solution; and wherein applying a third filter having a third fineness to the dirty brine solution to output the cleaned brine solution from the third filter further comprises extracting solids larger than the third fineness from the dirty brine solution.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to describe the manner in which at least some aspects of this disclosure can be obtained, a more particular description will be rendered by reference to specific embodiments thereof which are illustrated in the accompanying drawings. Understanding that these drawings depict only example embodiments of the invention and are not therefore to be considered to be limiting of its scope, embodiments of the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, which include:

[0024] FIG. 1A is a schematic diagram of a prior art meat processing system;

[0025] FIG. 1B is a detailed schematic diagram of a prior art evaporator and salt concentrator of the prior art meat processing system of FIG. 1A;

[0026] FIG. 1C is an additional detailed schematic diagram of additional aspects of the prior art evaporator and salt concentrator of FIG. 1B;

[0027] FIG. 2A is a schematic diagram of a meat processing system having a brine curing system in accordance with one or more embodiments of the invention;

[0028] FIG. 2B is an overhead blueprint diagram of a brine curing system having a brine cleaning system in accordance with one or more embodiments of the invention;

[0029] FIG. 2C is a detailed schematic diagram of a brine cleaning system having a brine cooker, brine filter, and brine storage in accordance with one or more embodiments of the invention;

[0030] FIG. 3A is a detailed schematic diagram of a brine cooker in accordance with one or more embodiments of the invention;

[0031] FIG. 3B is an additional detailed schematic diagram of additional aspects of the brine cooker of FIG. 3A in accordance with one or more embodiments of the invention;

[0032] FIG. 4 is a detailed schematic diagram of a brine filter in accordance with one or more embodiments of the invention;

[0033] FIG. 5 is a detailed schematic diagram of a brine storage in accordance with one or more embodiments of the invention; and

[0034] FIG. 6 is a flowchart of a series of acts in a method of brine cleaning in accordance with one or more embodiments of the invention.

DETAILED DESCRIPTION

[0035] Embodiments of the present invention generally concern one or more aspects of cleaning brine solution. More particularly, at least some embodiments of the invention relate to a brine solution cleaning system that includes a brine cooker, a brine filter, and a brine storage unit. The brine cooker heats a dirty brine solution to separate the dirty brine solution into a liquid portion and a solids portion. The brine filter removes the solids portion from the dirty brine solution and is coupled to the brine cooker to receive the liquid portion and the solids portion of the dirty brine solution from the brine cooker. The brine storage unit accumulates the liquid portion of the dirty brine solution and is coupled to the brine filter to receive the liquid portion of the dirty brine solution from the brine filter.

[0036] Similarly, at least some embodiments of the invention relate to a brine cooker that includes a brine container, a heating element, and a solids outlet. The brine container holds a dirty brine solution. The heating element heats the dirty brine solution within the brine container to separate the dirty brine solution into a liquid portion and a solids portion. The solids outlet removes a portion of the solids portion of the dirty brine solution from the brine container.

[0037] Moreover, at least some embodiments of the invention relate to a brine filter that includes a first filter, a second filter, a liquid outlet, and a third filter. The first filter cleans a dirty brine solution. The second filter then cleans the dirty brine solution after the first filter. The liquid outlet then provides a flow of a liquid portion of the dirty brine solution after the second filter. The third filter cleans the flow of the liquid portion of the dirty brine solution and receives the flow of the liquid portion of the dirty brine solution from the liquid outlet.

[0038] Furthermore, at least some embodiments of the invention relate to a brine storage unit that includes a brine storage container, a liquid inlet, and a liquid outlet. The brine storage container holds a dirty brine solution. The liquid inlet is coupled to the brine storage container to receive the dirty brine solution into the brine storage container. The liquid outlet is coupled to the brine storage container to provide the dirty brine solution out of the brine storage container.

[0039] Additionally, at least some embodiments of the invention relate to a method of cleaning brine that includes separating solids within a dirty brine solution. Then, removing the solids from the dirty brine solution to create a clean brine solution. Following the removal of the solids to create the clean brine solution, the method includes accumulating the clean brine solution. Solids within a dirty brine solution, such as proteins and other coagulants, can be separated from a liquid portion of the dirty brine solution by heating the dirty brine solution to 212 degrees Fahrenheit for about 10 minutes. Additionally, solids can be removed from the dirty brine solution by employing a filter, such as a screen filter.

[0040] In general, FIGS. 2A-2C show an example embodiment of a brine cleaning system that includes a brine cooker, a brine filter, and a brine storage. More specifically, FIG. 2A illustrates a schematic diagram of a meat processing system 200 that includes a meat processing facility 210 (e.g., a slaughterhouse or meat packing plant). Within meat processing facility 210, a hide processing system 220 is used to process the hides removed from the animals. Hide processing system 220 further includes brine curing system 230, which is used to preserve the hides and prevent them from decaying or decomposing.

[0041] Brine curing system 230 includes brine curing hide vats 240 in which fresh hides are immersed in brine solution. The dirty brine solution 250 created from the brine curing hide vats 240 is then sent to a brine cooker 280 of brine cleaning system 270 (e.g., using a pipe and a pump). Brine cooker 280 then heats the dirty brine solution 250 so that the dirty brine solution 250 separates into solid portions and liquid portions as a result of coagulation of the proteins and other organic material typically found in dirty brine solution 250. Once the dirty brine solution 250 has been heated sufficiently to separate into liquid and solid portions, the dirty brine solution 250 is sent (e.g., using an incline and/or a pipe and a pump) through to brine filter 290 to remove the solid portions from the dirty brine solution 250, leaving only a liquid portion of the dirty brine solution 250. The remaining liquid portion of the dirty brine solution 250 is then sent (e.g., using a pipe and a pump) to brine storage 298 where it is accumulated and can at that point be considered clean brine solution because the coagulated proteins and other organic material have been substantially removed such that the liquid portion of the dirty brine solution 250 is primarily only water and salt. Thus, the clean brine solution can then be sent (e.g., using a pipe and a pump) to evaporator and salt concentrator 260 for further cleaning, recycling, and disposal of the clean brine solution.

[0042] FIG. 2B illustrates an overhead blueprint diagram of a brine curing system 230 having brine curing hide vats 240 which create a dirty brine solution 250 that is pumped by pump 242 through a pipe 243 to brine cooker 280. Brine cooker 280 then heats the dirty brine solution 250 until it separates into liquid and solid portions. Then the liquid and solid portions of dirty brine solution 250 are moved from brine cooker 280 to brine filter 290 (e.g., using an incline and/or a pipe and a pump). Once brine filter 290 filters out the solid portion of dirty brine solution 250, then the liquid portion of dirty brine solution that made it through brine filter 290 is pumped by pump 292 through a pipe 293 to brine storage 298. Pump 299 then pumps the brine solution from brine storage 298 to evaporator and salt concentrator 260 over a pipe 294. Evaporator and salt concentrator 260 recycles the water and salt components of the brine solution by, in part, using pump 262 to pump a slurry of the brine solution through a pipe 263 to salt settler 264, which removes reusable salt crystals from the slurry and uses auger 266 to feed reusable salt crystals back into brine curing hide vats 240. Any slurry of the brine solution that is not reusable is then pumped by pump 268 through pipe 269 back to evaporator and salt concentrator 260.

[0043] FIG. 2C is a detailed schematic diagram of a brine cleaning system 230 having a brine cooker 280, brine filter 290, and brine storage 298. More specifically, brine cooker 280 receives dirty brine solution 250 from pipe 243 and heats the dirty brine solution 250 until it separates into liquid and solids portions. Then the liquid and solids portions of dirty brine solution 250 are passed to brine filter 290 which removes the solids portion from the dirty brine solution 250 and uses pump 292 to pass the liquid portion of dirty brine solution 250 to brine storage 298 through pipe 293. Brine storage 298 then accumulates the liquid portion of the dirty brine solution 250 that passed through the brine filter 290. Brine storage 298 also uses pump 299 to pass the liquid portion of the dirty brine solution 250 to evaporator and salt concentrator 260 through pipe 294, which further cleans, recycles, and disposes of the liquid portion of dirty brine solution 250. In particular, evaporator and salt concentrator 260 uses pump 262 to send a slurry of the dirty brine solution 250 through pipe 263 to a salt settler 264 which reuses salt crystals in the dirty brine solution 250 and feeds such reusable salt crystals back into brine curing hide vats 240 using auger 266. The salt settler 264 also pumps back any unused slurry through pipe 269 to the flash separator of evaporator and salt concentrator 260 using pump 268.

[0044] In general, FIGS. 3A-3B show an example embodiment of a brine cooker 300. Turning to FIG. 3A, a detailed schematic diagram of a brine cooker 300 is illustrated. More specifically, brine cooker 300 includes a brine container 310 that holds a dirty brine solution received into the brine container 310 through inlet 320, which may further include a gate 320a and a control valve 320b. Brine container 310 also includes a top portion having an inner wall 312 and an outer wall 314. Thus, as illustrated, a cavity 316 is formed by the inner wall 312 and the outer wall 314, wherein the cavity 316 receives a portion of the solids portion of the dirty brine solution that flows over the inner wall 312.

[0045] The brine cooker 300 also includes a heating element 330 that heats the dirty brine solution within the brine container 310 to separate the dirty brine solution into a liquid portion and a solids portion. The heating element 330 includes upper sparging tubes 332a and lower sparging tubes 332b which sparge steam into the dirty brine solution. The steam enters into brine container 310 to activate heating element 330 through a heating inlet 334, which may include a pressure control valve 334a and a globe valve 334b. The steam exits brine container 310 through heating outlet 336, which may further include a globe valve 336a, a gate 336b, and a steam trap 336c positioned therebetween. In one or more other embodiments, the heating element 330 may include a sparging ring or coil. Additionally, in one or more embodiments, other heating elements may be used to heat the dirty brine solution within the brine container 310, such as a cable heater, a cartridge heater, a ceramic fiber heater, a flexible heater, a strip heater, a tubular heater, or an immersion heater.

[0046] The brine cooker 300 also includes a liquid outlet 340 coupled to the brine container 310 to remove a portion of the liquid portion of the dirty brine solution from the brine container 310. Liquid outlet 340 may further include a first gate 340a, a second gate 340b, a control valve 340c positioned between the first gate 340a and the second gate 340b, and a pump 342 positioned between the control valve 340c and the second gate 340b to provide a flow of a portion of the liquid portion of the dirty brine solution from the brine container 310 to a brine filter. In one or more embodiments, liquid outlet 340 is a pipe.

[0047] The brine cooker 300 additionally includes solids outlet 350 coupled to the brine container 310 to remove a portion of the solids portion of the dirty brine solution that flows over the inner wall 312 from brine container 310 to a brine filter. In one or more embodiments, solids outlet 350 may be an incline or a pipe.

[0048] The brine cooker 300 further includes another liquid outlet 360 coupled to the brine container 310 to remove a portion of the liquid portion of the dirty brine solution from the brine container 310 to a brine filter. Moreover, liquid outlet 360 may further include a gate 360a and a control valve 360b. In one or more embodiments, liquid outlet 360 is a pipe. The outlets of the brine cooker 310, namely liquid outlet 340, liquid outlet 360, and solids outlet 350, may be used to move the solid and liquid portions of the dirty brine solution from the brine cooker 300 to a brine filter. Furthermore, liquid outlet 340 and liquid outlet 360 primarily transport liquid portions of the dirty brine solution, but such liquid portions may still include some solids. In contrast, solids outlet 350 primarily transports solids portions of the dirty brine solution, but such solids portions may still include some liquids. Nevertheless, the solids and liquids that are outlet from brine container 310 by liquid outlet 340, liquid outlet 360, and solids outlet 350 are ultimately filtered by a brine filter as discussed in greater detail below.

[0049] Turning to FIG. 3B, an additional detailed schematic diagram of additional aspects of the brine cooker 300 of FIG. 3A is illustrated. As previously described, brine cooker 300 includes a brine container 310 that holds a dirty brine solution received through inlet 320. Brine container 310 also includes a top portion having an inner wall 312 and an outer wall 314. Thus, as illustrated, a cavity 316 is formed by the inner wall 312 and the outer wall 314. Brine cooker 300 also includes a heating element 330 that receives steam through heating inlet 334 and includes upper sparging tubes 332a and lower sparging tubes 332b. The steam then exits at heating outlet 336. Additionally, brine cooker 300 includes liquid outlet 340, liquid outlet 360, and solids outlet 350.

[0050] FIG. 3B also illustrates a top plan view 300a of brine cooker 300. Top plan view 300a shows that brine cooker 300 includes brine container 310 having inner wall 312 and outer wall 314 which form cavity 316. Within brine container 310 heating element 330 is disposed. Heating element 330 includes upper sparging tubes 332a which are arranged in a ladder or cross-bar like arrangement, with heating inlet 334 feeding hot steam into upper sparging tubes 332a of the heating element 330 and then the heating outlet 336 returning any unused steam out of the brine container 310. Upper sparging tubes 332a and lower sparging tubes 332b can be arranged in this ladder or cross-bar like arrangement, thereby each providing an array of sparging tubes to more evenly heat the dirty brine solution within brine container 310 of brine cooker 300.

[0051] FIG. 3B also illustrates a bottom plan view 300b of brine cooker 300. Bottom plan view 300b shows that the bottom of brine container 310 may be tapered, like an upside-down pyramid shape, terminating in the center with liquid outlet 340. Brine container 310 further includes outer wall 314.

[0052] FIG. 3B further illustrates a perspective view 300c of brine cooker 300, which illustrates brine container 310 includes, as already described, a top portion having an inner wall 312 and an outer wall 314. Thus, as illustrated, a cavity 316 is formed by the inner wall 312 and the outer wall 314, wherein the cavity 316 receives a portion of the solids portion of the dirty brine solution that flows over the inner wall 312 and into cavity 316. Additionally, perspective view 300c shows that liquid outlet 360 may be coupled to a solids outlet 350 in the form of an incline or ramp located at the bottom of the cavity 316 formed between inner wall 312 and outer wall 314, such that solids that overflow the inner wall 312 may slide out of the brine cooker 300 to be passed to a brine filter. Alternatively, solids outlet 350 may also be a pipe as shown in in FIG. 3A. Also, perspective view 300c shows that liquid outlet 340 and liquid outlet 360 may be used to remove liquid portions of the dirty brine solution from the brine container 310.

[0053] Turning to FIG. 4, a detailed schematic diagram of a brine filter 400 is illustrated. More specifically, brine filter 400 includes a first filter 410, a second filter 420, and a third filter 440. Additionally, brine filter 400 includes a solids outlet 412, a liquid outlet 414, and a pump 430. Brine filter may receive the dirty brine solution from one or more inlets, such as inlets 402 and 404 (e.g., coming from liquid outlet 340, liquid outlet 360, and solids outlet 350 as shown in FIGS. 3A and 3B). Inlets 402 and 404 may provide to brine filter 400 a liquid portion of the dirty brine solution, a solids portion of the dirty brine solution, or a combination of both. The first filter 410 cleans a dirty brine solution and then second filter 420 cleans the dirty brine solution after the first filter. Liquid outlet 414 provides a flow of a liquid portion of the dirty brine solution after the second filter 420 and sends the liquid portion to pump 430 through pipe 416. Pump 430 them provides the liquid portion to third filter 440 through pipe 417. Third filter 440 then cleans the flow of the liquid portion of the dirty brine solution. After passing through third filter 440, the cleaned liquid portion of the dirty brine solution travels through pipe 418 to a brine storage, such as brine storage 298 of FIGS. 2A-2C. Additionally, pipe 418 may include gate 419 to control the flow of cleaned brine solution into brine storage. In one or more embodiments, first filter 410 may have a first fineness, such as a SWECO® 50 mesh filter, second filter 420 may have a second fineness greater than the first fineness, such as a SWECO® 200 mesh filter, and third filter may have a third fineness, such as 400 microns. Additionally, the filters of brine filter 400 can be any suitable filter that further removes solids from the dirty brine solution, such as screen filters and bag filters.

[0054] Turning to FIG. 5, a detailed schematic diagram of a brine storage 500 is illustrated. In particular, brine storage 500 includes a brine storage container 510, a liquid inlet 512, and a liquid outlet 514. Additionally, brine storage 500 includes an additional liquid outlet 516, as well as a pump 520. Liquid inlet 512 and liquid outlets 514 and 516 may all respectively be coupled to corresponding pipes 502, 504, and 506, with pump 520 providing a flow of liquid from the brine storage container 510 out of liquid outlet 514 and through pipe 504 (e.g., back into brine cooker 280 as shown in FIG. 2C or back into brine cooker 300 through inlet 320 as shown in FIGS. 3A-3B). Liquid inlet 512 may receive a flow of cleaned brine solution into brine storage container 510 through pipe 502 (e.g., from brine filter 400 of FIG. 4, such as after cleaned brine solution passes through third filter 440). Liquid inlet 516 may receive a flow of brine solution into brine storage container 510 through pipe 506 (e.g., from evaporator and salt concentrator 260 of FIGS. 2A-2C).

[0055] Turning to FIG. 6, a flowchart of a series of acts in a method of brine cleaning is shown. More specifically, FIG. 6 illustrates a method 600 that includes steps 610-630. In particular, the method 610 includes a first step of separating solids within dirty brine solution 610. This first step 610 can further include heating the dirty brine solution (e.g., in brine cooker 300 of FIGS. 3A-3B). More specifically, heating the dirty brine solution can further include heating the dirty brine solution at 212 degrees Fahrenheit for 10 minutes in order to cause solids within the dirty brine solution to coagulate. For example, typically when solids in a dirty brine solution coagulate from heating, the solids rise to the surface and the liquids settle to the bottom. This first step 610 can also include capturing coagulated solids within the dirty brine solution and removing the captured coagulated solids from a liquid portion of the dirty brine solution. More specifically, capturing coagulated solids within the dirty brine solution can further include causing coagulated solids to overflow a top of a brine cooker, thereby falling into a cavity of the brine cooker that is separate from an interior of the brine cooker used to heat the dirty brine solution (e.g., cavity 316 of brine cooker 300 of FIGS. 3A-3B). Additionally, removing the captured coagulated solids from a liquid portion of the dirty brine solution can include using an incline to cause the coagulated solids to be separated from the liquid portion of the dirty brine solution (e.g., by sliding the coagulated solids down solids outlet 350 of brine cooker 300 as shown in FIG. 3B). Alternatively or additionally, removing the captured coagulated solids from a liquid portion of the dirty brine solution can include using a pipe (with or without the assistance of a pump) to cause the coagulated solids to be separated from the liquid portion of the dirty brine solution (e.g., by transporting the coagulated solids through a pipe connected to solids outlet 350 of brine cooker 300 as shown in FIG. 3A).

[0056] The method 600 also includes a second step of removing solids from the dirty brine solution to create a clean brine solution 620. This second step 620 can further include filtering the solids from the dirty brine solution. More specifically, filtering the solids from the dirty brine solution can further include applying a first filter having a first fineness to the solids of the dirty brine solution, applying a second filter having a second fineness to the solids of the dirty brine solution, and applying a third filter having a third fineness to the solids of the dirty brine solution to output the clean brine solution from the third filter (e.g., first filter 410, second filter 420, and third filter 440 of brine filter 400 as shown in FIG. 4). Applying a first filter having a first fineness to the solids of the dirty brine solution can include extracting solids larger than the first fineness from the dirty brine solution through a first outlet (e.g. the top of brine filter 400 as shown in FIG. 4). Along similar lines, applying a second filter having a second fineness to the solids of the dirty brine solution can include extracting solids larger than the second fineness from the dirty brine solution through a second outlet (e.g. solids outlet 412 of brine filter 400 as shown in FIG. 4). Similarly, applying a third filter having a third fineness to the solids of the dirty brine solution to output the clean brine solution from the third filter can include extracting solids larger than the third fineness from the dirty brine solution (e.g., third filter 440 as shown in FIG. 4).

[0057] The method 600 further includes a third step of accumulating the clean brine solution 630. This third step 630 can further include storing the clean brine solution in a brine storage unit (e.g., brine storage 298 as shown in FIGS. 2A-2C). This step can further include outputting clean brine solution back a brine cooker for further cleaning (e.g., brine cooker 300 of FIGS. 3A-3B). Also, this step can include providing clean brine to a wastewater disposal site, such as a brine pond or similar.

[0058] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.