WO2011075129A1

WO2011075129A1 - Treatment of healthcare facility waste

Info

Publication number: WO2011075129A1
Application number: PCT/US2009/068450
Authority: WO
Inventors: David Lee Geschwendt; William E. Jones; Jerry M. Kulas; Matthew Scott Selby
Original assignee: Peerless Waste Solutions, Llc
Priority date: 2009-12-17
Filing date: 2009-12-17
Publication date: 2011-06-23

Abstract

An apparatus (10) and method to sterilize regulated medical waste and/or mutilate confidential patient documents. An apparatus (10) to process medical waste comprising a feed hopper (14) adapted to receive waste material therein, an integral shredder (36) adapted to shred waste material received from the feed hopper (14), a heated auger (42) adapted to sterilize waste material received from the shredder (36), a discharge chamber (558) comprising an inlet (564) and an outlet (478) adapted to receive sterilized waste material received from the heated auger (42), a first retractable seal (438) located between the feed hopper (14) and the heated auger (42), a second retractable seal (566) between the heated auger (42) and the inlet (564) of the discharge chamber (558); and a third retractable seal (591) between the outlet of the discharge chamber (558) and an atmosphere external to the apparatus (10).

Description

TREATMENT OF HEALTHCARE FACILITY WASTE

BACKGROUND

[0001] The present invention relates to an apparatus and method of treating medical waste and, more specifically, to an apparatus and method that allows the simultaneous treatment of multiple batches of medical waste by compartmentalizing the steps of loading, shredding/sterilizing, and unloading.

[0002] Healthcare facilities generate waste. Blood, body fluids, and other potentially infectious materials contaminate some of the waste that a healthcare facility generates. Such contaminated waste poses a risk of transmitting infection and disease, which endanger human health.

[0003] Several decades ago, governments began to regulate the contaminated waste that healthcare facilities generate. Thus, people began to refer to the contaminated waste as "regulated medical waste." Regulated medical waste is sometimes referred to as "bio- hazardous waste" or "infectious medical waste." The regulations greatly increased the costs to healthcare facilities to dispose of the regulated medical waste; estimates are that the cost to dispose of regulated medical waste is eight to ten times the cost to dispose of non-regulated solid waste.

[0004] Some specific examples of regulated medical waste include: liquid medical waste, such as blood, blood products (including plasma), body fluids (including semen, spinal fluid, and saliva); isolation waste, such as samples taken from humans or animals infected with a communicable disease; microbiological waste, such as research cultures and culture dishes; pathological and anatomical waste, such as human tissue, organs, and body parts removed via trauma, surgery, or a biopsy; sharps, such as needles, syringes, pipettes, broken glass from the laboratory, blades, and capillary tubes; and animal waste, such as animal carcasses, body parts, and bedding. This description of regulated medical waste is not exclusive.

[0005] Not all waste that a healthcare facility generates is regulated medical waste. For example, a healthcare facility may desire to retain and reuse an instrument used to provide healthcare rather than dispose of it. The healthcare facility may desire to sterilize the instrument before using the instrument again. In addition, a healthcare facility handles and processes many documents, some of which constitute confidential health information about a patient. The government has regulated the handling and disposal of such confidential health information. Moreover, a healthcare facility generates general waste such as food waste, laundry, construction items, and typical household-like trash, which can be treated separately and not necessarily by the apparatus and methods described herein.

SUMMARY OF THE INVENTION

[0006] Described herein are several embodiments of an apparatus that can sterilize regulated medical waste in a cost-effective manner and can dispose of confidential health information. A method to sterilize regulated medical waste with steam is additionally described herein.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0007] FIG. 1 depicts a perspective view of a first embodiment of a waste treatment apparatus 10;

[0008] FIG. 2 depicts a side perspective view of a feed hopper 14 of the first embodiment of waste treatment apparatus 10, with an interlocked door 16 closed;

[0009] FIG. 3 depicts a front view of the feed hopper 14 of the first embodiment, with the interlocked door 16 opened;

[0010] FIG. 4 depicts a rear perspective view of the feed hopper 14 of the first embodiment;

[0011] FIG. 5 depicts a front exploded view of the interlocked door 16 of the first embodiment showing an interlock assembly 190;

[0012] FIG. 6 depicts a perspective view of the cross-section VI— VI, FIG. 5;

[0013] FIG. 7 depicts a rear view of the interlocked door 16 of the first embodiment;

[0014] FIG. 8 depicts a perspective view of a cross 218 of the interlock assembly 190 of the interlocked door 16 of the first embodiment;

[0015] FIGS. 9A-9C are schematic depictions of apparatus 10 of the first embodiment and a second embodiment, showing process flows and controls;

[0016] FIG. 10 depicts a perspective view of condenser piping assembly 642 of the first and second embodiments;

[0017] FIG. 11 depicts a side view of an integral shredder 36 of the first embodiment, in relationship to the feed hopper 14;

[0018] FIG. 12 depicts a perspective view of the integral shredder 36 of the first embodiment;

[0019] FIG. 13 depicts a perspective view of the integral shredder 36 of the first embodiment, at cross-section XII-XII, FIG. 12;

[0020] FIG. 14 depicts a perspective view of the integral shredder 36 of the first embodiment, at cross-section XIV-XIV, FIG. 12;

[0021] FIG. 15 depicts a front view of the integral shredder 36 of the first embodiment; [0022] FIG. 16 depicts a side view of the integral shredder 36 of the first embodiment, highlighting an actuator assembly 408 and associated parts;

[0023] FIG. 17 depicts a perspective view of the bomb bay door assembly 438 of the first embodiment;

[0024] FIG. 18 depicts a perspective view of an actuator assembly 684 of the first embodiment;

[0025] FIG. 19 depicts a perspective view of a spacer 460 of the first embodiment;

[0026] FIG. 20 depicts a perspective view of a heated auger 42 of the first embodiment;

[0027] FIG. 21 depicts a perspective view at cross section XXI -XXI, FIG. 20, of the heated auger 42 of the first embodiment;

[0028] FIG. 22 depicts a perspective view of a discharge chamber 558 of the first embodiment;

[0029] FIG. 23 depicts a perspective view of a horizontal slide gate unit 720 of the second embodiment in relation to the feed hopper 14 and the integral shredder 36;

[0030] FIG. 24 depicts a perspective view of a horizontal slide gate unit 720 of the second embodiment;

[0031] FIG. 25 depicts a perspective view of a horizontal slide gate unit 720 of the second embodiment at cross section XXV-XXV, FIG. 23;

[0032] FIG. 25 A depicts an enlarged perspective view of segment XXVA, FIG. 25;

[0033] FIG. 25B depicts an enlarged perspective view of segment XXVB, FIG. 25;

[0034] FIG. 26 depicts an overhead view of a back side 794 of a seal plate 738 of the second embodiment;

[0035] FIG. 26A depicts an enlarged perspective view of section XXVIA, FIG. 26, to highlight a slot 790 of the seal plate 738 of the second embodiment;

[0036] FIG. 26B depicts an enlarged perspective view of section XXVIB, FIG. 26, showing extensions 802 of seal 792 placed through slots 790 of seal plate 738 of the second embodiment;

[0037] FIG. 27 depicts a perspective view of seal 792 of the second embodiment;

[0038] FIG. 28 depicts a perspective view of a motor mount 806 of the second embodiment;

[0039] FIG. 29 depicts a perspective view of an outlet 722 of the heated auger 42 of the second embodiment; and

[0040] FIG. 30 depicts a perspective view of a cart dumper 78 in a loading position, shown next to the apparatus 10; and [0041] FIG. 31 depicts a perspective view of the cart dumper 78 in an unloading position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] For purposes of description herein, the terms "upper," "lower," "right," "left," "rear,"

"front," "vertical," "horizontal," and derivatives thereof shall relate to the invention as oriented in FIG. 1. However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that het specific devices and processes illustrated in the attached drawings, and described in the following specification are exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.

[0043] 1. A First Embodiment.

[0044] As shown in FIG. 1, in a first embodiment, apparatus 10 can comprise frame 606, feed hopper 14, integral shredder 36, heated auger 42, bomb bay door assembly 438, programmable logic controller 68, and discharge chamber 558. The bomb bay door assembly 438 acts as a first retractable seal between the feed hopper 14 and the heated auger 42. The discharge chamber 558 comprises shield 566, which acts as a second retractable seal between the heated auger 42 and the inlet of the discharge chamber 558, and shield 591, which acts as a third retractable seal between the outlet of the discharge chamber and the atmosphere external to the apparatus 10. This compartmentalization of the apparatus, allows sterilization of one batch of medical waste in the heated auger42, while one batch is being unloaded from the discharge chamber 558 and/or another batch is being loaded into the feed hopper 14.

[0045] A. The Frame.

[0046] Frame 606 can provide structural support for the other elements of apparatus 10.

Frame 606 can comprise front vertical supports 608, mid-vertical supports 610, back vertical supports 612, bottom length supports 614, top length supports 616, bottom width supports 618, top width supports 620, and other supports 622 placed as needed to support the other elements of apparatus 10. The frame 606 can be molded metal segments welded together. The frame 606 can further comprise feet 624. [0047] B. The Feed Hopper.

[0048] Feed hopper 14 (FIG. 2) can comprise an interlocked door 16. The interlocked door

16 can comprise back cover 168, seal 170, limit switch activator 172, flange 178, flange 182, front side 186, and interlock assembly 190. Back cover 168 covers the inner components of the interlock assembly 190. Seal 170 prevents liquid and gas from escaping feed hopper 14 through the sides of the interlocked door 16, when the inside of the feed hopper 14 is pressurized. Limit switch activator 172 comprises flange 174 and projection 176. Limit switch activator 172 can be connected to the front side 186 of the interlocked door 16 via the use of bolts 188. Flange 178 comprises aperture 180. Flange 182 comprises aperture 184.

[0049] Interlock assembly 190 (FIGS. 2, 5 and 6) can comprise a handle 28, disc 192, pivot

194, cross 218, arms 256, and lock rods 266. Handle 28 can be connected to disc 192. For example, disc 192 can have aperture 200, which can be threaded to receive handle 28. Disc 192 can have aperture 196 to receive first end 198 of pivot 194. Wider area 202 of pivot 194 allows disc 192 to retain pivot 194. Disc 192 can have recess surface 204 that is flush with first end surface 206 of pivot 194. Pivot 194 can have recess 208, which can be threaded, to receive bolt 210. One side of washer 212 lies flush against recess surface 204 of disc 192 and first end surface 206 of pivot 194. The other side of washer 212 lies flush against the head of bolt 210. Pivot 194 has recess 213, which can receive an O-ring. The O-ring helps prevent fluid (gas or liquid) from escaping from the inside of the feed hopper 14 to the atmosphere when pressurized. Pivot 194 can comprise recess 626 and disc 192 can comprise recess 628. Recess 626 and recess 628 can be lined up and a piece of material (a "key") shaped to match the recess 626 and recess 628 can be placed within the volume formed by recess 626 and recess 628. The key ensures that rotation of disc 192 causes pivot 194 to rotate as well.

[0050] Pivot 194 (FIG. 6) can further comprise second end 214 and wider area 216. Cross

218 comprises aperture 220. Aperture 220 of cross 218 receives second end 214 of pivot 194. Second end 214 of pivot 194 comprises recess 222, and aperture 220 of cross 218 has recess 224. Recess 222 of pivot 194 is lined up with recess 224 of cross 218 and a key (not shown) fills recess 222 and recess 224. The key can be a piece of metal. When the key is inserted into the recesses 222 and 224, rotation of pivot 194 causes rotation of cross 218. Second end 214 of pivot 194 comprises recess 226, which can be threaded to receive bolt 228. Pivot 194 further comprises second end surface 230. Cross 218 further comprises surface 232. One side of washer 234 abuts both surface 232 of cross 218 and second end surface 230 of pivot 194, while the other side of washer 234 abuts head of bolt 228. Interlocked door 16 further comprises spacer 242. Spacer 242 provides additional space for placement of bushing 244. Bushing 244 reduces friction when pivot 194 rotates.

[0051] Cross 218 (FIG. 8) further comprises recess 246, which provides room for cross 218 to rotate around spacer 242. Cross 218 further comprises four inner flanges 248 equally spaced around the aperture 220 of cross 218. Cross 218 further comprises four outer flanges 250. The four outer flanges 250 are spaced to correspond to the four inner flanges 248. Each of the four inner flanges 248 comprise an aperture 252. Each of the corresponding outer flanges 250 comprise an aperture 254 to match the corresponding aperture 252 of the corresponding inner flange 248.

[0052] Each of the arms 256 (FIG. 5) can comprise an inner end 258 and an outer end 260.

The inner end 258 comprises an aperture to match the aperture 254 of the outer flange 250 of the cross 218 and aperture 252 of the inner flange 248 of the cross 218. These matching apertures receive a member around which to rotate, such as bolt 263. Thus, rotation of cross 218 causes each of the arms 256 to move. Outer end 260 of arms 256 comprise an aperture (not shown), as discussed below.

[0053] Each of the lock rods 266 comprises a lock end 268 and receiving end 270. The lock end 268 is designed to enter a matching recess (described below) in the door well 288 of the feed hopper 14. The receiving end 270 of the lock rod 266 comprises a recess 272 placed between fingers 274. Each finger 274 comprises an aperture (not shown) to match the aforementioned aperture of outer end 260 of arm 256, and a member, such as bolt 278, is placed through these apertures. The outer end 260 of arm 256 and receiving end 270 of the lock rod 266 thus can rotate around bolt 278. Therefore, when cross 218 rotates, arm 256 moves, causing lock rod 266 to either proceed into the matching recess in the door well 288 of the feed hopper 14, thereby locking the interlocked door 16, or out from the recess in the door well 288, thereby unlocking the interlocked door 16.

[0054] The feed hopper 14 (FIG. 2) further comprises flanges 282. Each of the flanges 282 comprises an aperture 284. Member, such as bolt 286, is placed through aperture 180 of flange 178 of the interlocked door 16 and into aperture 284 of flange 282 of feed hopper 14. Member, such as bolt 286, is placed through aperture 184 of flange 182 of interlocked door 16 and into aperture 284 of the other flange 282 of the feed hopper 14. Interlocked door 16 can thus open and close, rotating around bolts 286.

[0055] The feed hopper 14 (FIG. 3) further comprises door well 288. Door well 288 comprises four recesses 289; one recess 289 at the midway point of each of the four sides of the door well 288. The recesses 289 receive lock plates 290, such as via the use of bolts 292. Each of the lock plates 290 comprise an aperture 294. The aperture 294 is sized to receive lock end 268 of lock rod 266.

[0056] The feed hopper 14 (FIG. 4) further comprises switch box 21. Switch box 21 comprises limit switch 20. Switch box 21 is situated so that projection 176 of limit switch activator 172 pushes against switch 20 when the interlocked door 16 is closed. The switch 20 thus recognizes that interlocked door 16 is closed and communicates such to the programmable logic controller 68.

[0057] The feed hopper 14 further comprises inner chamber 296. Inner chamber 296 comprises back wall 298 and aperture 674. Back wall 298 comprises aperture 300, aperture 302, aperture 304, aperture 306, and grate 308. Aperture 300 can be a port to receive a pressure transducer 634. Aperture 302 can be a port to receive a thermocouple 636. Aperture 306 can be an exit port for piping leading to a heat exchanger and vacuum pump (also described below). Grate 308 can be placed over exit port apertures 304 and 306, to prevent debris from entering into the plumbing system on the other side of feed hopper 14 via apertures 304 and 306.

[0058] Inner chamber 296 further comprises top wall 310. Top wall 310 comprises apertures

312 and 314. Aperture 314 can be an inlet port for cooling water. The cooling water can travel through cooling coil 316. Aperture 312 can be an outlet port for the cooling water. Brace 317 helps retain the cooling coil 316 near the top wall 310. The cooling coil 316 helps to cool and condense steam that may have developed in the inner chamber 296 during use before the user opens the interlocked door 16 to add another load of regulated medical waste. Inner chamber 296 further comprises an open bottom 318.

[0059] Feed hopper 14 (FIG. 4) further comprises bottom plate 320. The bottom plate 320

(FIG. 11) allows the feed hopper 14 to be attached to integral shredder 36, separated by a gasket 322.

[0060] Feed hopper 14 can further comprise external locking mechanism 900. External locking mechanism 900 can comprise loop 902, loop 904, pin 906, and air cylinder 908. The programmable logic controller 68 controls air cylinder 908, which in turn causes pin 906 to extend or retract from air cylinder 908. Loop 902 can be fixedly attached to disc 192. Loop 904 can be fixedly attached to the front side 186 of interlocked door 16. The apertures that loops 902 and 904 make roughly match in size, so that when the loops 902 and 904 are aligned, pin 906 can proceed through both loops 902 and 904. When the programmable logic controller 68 causes pin 906 to extend through both loop 902 and loop 904, the user is unable to open the door, because the user cannot cause disc 192 to rotate. In practice, when the user presses the start button 30, the programmable logic controller 68 causes pin 906 to extend from air cylinder 908 and thus locks the interlocked door 16. At the end of the operation and when the pressure within inner chamber 296 of feed hopper 14 has reduced to the appropriate level (described below), the programmable logic controller 68 causes the pin 906 to retract back into air cylinder 908 and, thus, allows the user to open the interlocked door 16.

[0061] Valve 630 (FIG. 9) can control flow of cold water into cooling coil 316 via inlet aperture 314. The water flows through the cooling coil 316 and then out of the cooling coil 316 via outlet aperture 312. The water exiting the cooling coil 316 can be expelled to a waste (sewer) drain 632. Valve 631 can control the main cold water inlet into the system from water supply 638 and valve 630 can control the flow of water into cooling coil 316. Programmable logic controller 68 can control the opening and closing of valves 630 and 631.

[0062] Pressure transducer 634 communicates with inner chamber 296 of feed hopper 14 through aperture 300, measures the pressure, and communicates the pressure to the programmable logic controller 68. Connected in parallel to the pressure transducer 634 is relief valve 656, which then vents to drain 632 if a predetermined pressure within inner chamber 296 is reached, and vent valve 658, which programmable logic controller 68 controls and leads to drain 632.

[0063] Thermocouple 636 extends into inner chamber 296 of feed hopper 14 through aperture 302, measures the temperature, and communicates the temperature to the programmable logic controller 68.

[0064] Aperture 304 leads from the inner chamber 296 of feed hopper 14 through piping, flow through which is controlled by valve 640, then through condenser piping assembly 642, then through piping to HEPA filter 650. Blower 652 drives the fluid flow from the inner chamber 296 to the HEPA filter 650, by creating a vacuum force. The creation of this vacuum force evacuates air and other gases and allows the injected steam (discussed below) to more effectively penetrate the inserted controlled medical waste. Gaseous contents are then expelled from the HEPA filter 650, through blower 652, and out to the atmosphere through exhaust 654. Liquid contents are diverted to drain 632 before reaching HEPA filter 650. A vacuum break (such as a valve to atmosphere pressure) can be included in the piping, to help the liquid contents reach the drain through gravity force. Programmable logic controller 68 can control the blower 652. [0065] Condenser piping assembly 642 (FIG. 10) comprises piping 648, spray nozzles 644 protruding into the interior of piping 648, and valve 646. Spray nozzles 644 provide a spray of cold water over the gaseous contents (mostly steam) traveling through piping 648 from the inner chamber 296 of feed hopper 14, in order to reduce the temperature of the gaseous contents before the gaseous contents are exhausted from the apparatus 10. The supply of cold water to spray nozzles 644 comes from water supply 638 and through valve 646. Programmable logic controller 68 controls the opening and closing of valve 646.

[0066] Aperture 306 provides access from the inner chamber 296 of feed hopper 14 to piping. The piping leads to valve 660. Programmable logic controller 68 controls the opening and closing of valve 660. Piping leads from valve 660 to HEP A filter 662. Piping leads from HEPA filter 662 to heat exchanger 664, then to vacuum pump 668, then to gas/liquid separator 672 (gas is subsequently vented to atmosphere and the liquid discharged to drain 632). Cold water from water supply 638 can be the heat exchange medium for heat exchanger 664. Valve 666 controls the opening and closing of the piping for the cold water entering the heat exchanger 664 from water supply 638. Programmable logic controller 68 controls the opening and closing of valve 666. The water exiting heat exchanger 664 is then discharged to drain 632. Vacuum pump 668 can be a venturi type vacuum pump, with the vacuum force created by water incoming from water supply 638 (valve 670 controlling incoming water flow)— valve 671 controls water flow exiting vacuum pump 668 and the exiting water is discharged to drain 632. Programmable logic controller 68 controls valves 670 and 671. Vacuum pump 668 can alternatively be one of various designs, such as a water ring, dry, or reciprocating type pump.

[0067] Aperture 674 provides access from the inner chamber 296 of feed hopper 14 to piping. The piping leads to valve 676. Programmable logic controller 68 controls valve 676. Piping from valve 676 leads to a steam supply, such as boiler 678 (or any other steam supply in the facility). Alternatively, the steam supply may already have a valve, rendering valve 676 superfluous. Boiler 678 can be a Reimers® Model RH-30 (by Electra Steam, Inc., Clear Brook, Virginia). Thus, valve 676 (Fig 9A) controls the admission of steam into the inner chamber 296 of feed hopper 14 through aperture 674.

[0068] C. The Integral Shredder.

[0069] As depicted in FIGS. 11 through 16, integral shredder 36 can comprise an open top

323, a top surface 324, first side surface 328, and second side surface 330. Top surface 324 comprises apertures 326. The apertures 326 can receive members, such as bolts, to attach the bottom plate 320 of the feed hopper 14 to the top surface 324 of the integral shredder 36, separated by a gasket 322. Second side surface 330 (FIG. 13) comprises aperture 332. First side surface 328 comprises aperture 356.

[0070] Shredder assembly 334 (FIG. 13) can comprise motors 336 and 338. Motors 336 and

338 can be identical. Motors 336 and 338 can be helical worm gear motors, such as type SAF87DT100L4 (SEW-Eurodrive, Inc. USA (Lyman, South Carolina). Programmable logic controller 68 controls the activation and deactivation of motors 336 and 338 and the motors relay the amperage to programmable logic controller 68. Motor 336 drives shaft 340. Shaft 340 in turn causes cutter blades 342 and spacers 344 to rotate. Inner seal 346 and pre-oil impregnated bronze bearing 348 surround the motor end of shaft 340 at aperture 332 of the second side surface 330 of the integral shredder 36. The motor 336 is mounted to the second side surface 330 with the assistance of bearing housing/motor mount 350, which additionally houses the bronze bearing 348 and inner seal 346. Inner seal 352 and pre-oil impregnated bronze bearing 354 surround the opposite end of shaft 340 at aperture 356 of first side surface 328. Bearing housing/motor mount 358 covers the inner seal 352 and bronze bearing 354, provides support for the non-motor end of shaft 340, and allows motor 338 to mount to first side surface 328 (in the same way as bearing housing/motor mount 350 allows motor 336 to mount to second side surface 330).

[0071] Motor 338 likewise drives a shaft (not shown), which in turn causes cutter blades 360 and spacers 362 to rotate. Blades 360 and spacers 362 rotate in the opposite direction of cutter blades 342 and spacers 344. The opposite rotation enables shredding of objects placed between the cutter blades 360 and 342. The rotation of blades 360 may be at a different speed then the rotation of blades 342. The shaft driven by motor 338 is likewise surrounded by pre-oil impregnated bronze bearings and inner seals in the same manner as shaft 340 of motor 336 described above.

[0072] Integral shredder 34 (FIG. 14) further comprises pusher 364 and pusher 366. Pushers

364 and 366 can be curved pieces of material. Pushers 364 and 366 serve to push material to be shredded down towards and between the cutter blades 342 and 360. Pusher 364 is fixedly attached to shaft 368. Pusher 366 is fixedly attached to shaft 370. The width of pushers 364 and 366 should be sufficient to cover most or approximately all of the distance between first side surface 328 and second side surface 330. A flexible cover 710 is attached to the side of pusher 364 opposite of shaft 368. The opposite side of flexible cover 710 is attached to the nearest parallel top surface 324. A similar flexible cover 712 is attached to pusher 366 and the nearest parallel top surface 324 in the same way. The flexible covers 710 and 712 prevent material from falling between the pushers 364 and 366 and the side walls of the integral shredder 34. The flexible covers 710 and 712 can be, for example, chain link.

[0073] Mounting assembly 372 (FIG. 15) comprises L-bracket 374. L-bracket 374 is attached to second side surface 330, using, for example, apertures and bolts 376. Flange 378 is attached to L-bracket 374. Flange 378 has an aperture to receive bolt (as described below).

[0074] Actuator assembly 380 comprises an electrical linear actuator 382, such as EC090-

020MM1B0-000 by SKF Actuation System (Liestal) AG (Liestal, Switzerland). The electrical linear actuator 382 manipulates shaft 384. The end of shaft 384 away from the linear actuator 382 comprises fingers 386. Fingers 386 comprise apertures (not shown) to receive connector 396.

[0075] Arm 390 (FIG. 15) comprises first end 391 and second end 393. First end 391 has an aperture (not shown) and is placed between fingers 386 of shaft 384 so that the aperture of first end 391 and fingers 386 line up and connector 396, such as a bolt and nut, is placed within the apertures to connect shaft 384 to arm 390. Shaft 384 and arm 390 can thus rotate around connector 396. Shaft 368 is placed between fingers 395 of second end 393 of arm 390 and fixedly attached, so that movement of arm 390 turns shaft 368 (and thereby manipulates pusher 364).

[0076] Pusher 366 (FIG. 16) is connected to shaft 370. The end of shaft 370 that extends out of the interior of integral shredder 36 is fixedly attached to second end 398 of arm 402 between fingers 400. Arm 402 further comprises first end 404 with aperture (not shown). Actuator assembly 408 manipulates shaft 410. Programmable logic controller 68 controls actuator assembly 408. Shaft 410 comprises fingers 412, each of which comprise an aperture (not shown). First end 404 of arm 402 is placed between fingers 412 of shaft 410 so that the respective apertures line up. Connector 418, such as a bolt with nut, is placed within the apertures and fixedly attached, so that arm 402 and shaft 410 can rotate around connector 418.

[0077] Integral shredder 36 (FIG. 14) further comprises base 420, screen 422, and open bottom 423. Base 420 comprises a pair of recesses 430, one recess 430 on each side of the base 420 and a pair of apertures 434, one aperture 434 on each side. Screen 422 comprises a pair of curved meshes 424, the curvature of which approximately matches the curvature of cutter blades 342 and spacers 344. Screen 422 further comprises a flange 428 on both sides of the screen 422. The flange 428 is placed within the appropriate recess 430 of base 420. The curved meshes 422 comprise holes 426. Each flange 428 comprises an aperture with a female thread to receive the male thread of rotatable connector 436, which is additionally placed through aperture 434 of recess. Thus, rotation of connector 436 can either raise or lower the curved mesh 424 of screen 422 relative to cutter blades 342 and spacers 344. In use, the fineness of the shredded material is a function of (i) the distance between curved mesh 424 and the cutter blades 342/spacers 344 and (ii) the diameter of holes 426. Alternatively, the distance between curved mesh 424 and the cutter blades 342/spacers 344 could be fixed and non-adjustable. Increasing the number of holes 426 in the curved mesh 424 increases the flow rate of shredded material through the integral shredder 36. Material that falls through holes 426 can then fall through open bottom 423 of the integral shredder 36.

[0078] D. The Bomb Bay Door Assembly.

[0079] The apparatus 10 further comprises bomb bay door assembly 438 (FIG. 17). The bomb bay door assembly 438 comprises top platform 440, bottom platform 442, first side 444, second side 446, and interior chamber 448. Top platform 440 comprises apertures 450. Top platform 440 allows the bomb bay door assembly 438 to attach to base 420 of integral shredder 36, with a gasket placed in between, via the use of connectors placed through apertures 450 and matching apertures in the base 420 of the integral shredder 36. First side 444 comprises apertures 451 and apertures 452. Apertures 452 are connected to piping to valve 680, then to boiler 678. See FIG. 9C. Programmable logic controller 68 controls the opening and closing of valve 680. Thus, steam can be supplied to the interior chamber 448 of the bomb bay door assembly through apertures 452. Apertures 451 allow shafts 454 to extend from the interior chamber 448 to the exterior of the bomb bay door assembly 438. Each shaft 454 is fixedly attached to a door 456. When both doors 456 are closed, a seal is formed. Rotation of shaft 454 causes rotation of the attached door 456. Second side 446 can comprises apertures 458, such as to allow for additional steam supply to interior chamber 448, but apertures 458 can be capped. Bottom platform 442 comprises apertures 459. Material that falls through the open bottom 423 of the integral shredder 36 falls into the interior chamber 448 of the bomb bay door assembly 438 and onto the doors 456, if the doors 456 are in closed position.

[0080] Each shaft 454 (FIG. 18) is connected to an actuator assembly 684, which controls the rotation of shaft 454 and thus the opening and closing of door 456. The end of shaft 454 extending to the exterior of bomb bay door assembly 438 is connected to one end of lever 682. The other end of lever 682 comprises an aperture. Shaft 686 comprises fingers 690. Each finger 690 comprises an aperture (not shown) to match the aperture of lever 682, and the apertures receive member 694 (such as a bolt) around which to rotate. Thus, movement of shaft 686 causes movement of lever 682, and thus shaft 454. Actuator 696 manipulates shaft 686. Programmable logic controller 68 controls actuator 696. Actuator 696 can be fixedly attached to frame 606.

[0081] E. Spacer.

[0082] The apparatus 10 (FIG. 19) further comprises spacer 460. Spacer 460 provides additional space between the bomb bay door assembly 438 and the heated auger 42, to allow room for the doors 456 to fully extend downward (so that the door is approximately vertical relative to the ground). Spacer 460 comprises top platform 462, bottom platform 464, walls 465, and interior chamber 466. Top platform 462 comprises apertures 468, which match apertures 459 of bottom platform 442 of bomb bay door assembly 438, to accept connectors to attach spacer 460 to bomb bay door assembly 438, with a gasket placed in between. Bottom platform 464 comprises apertures 470, to allow for attachment to the heated auger 42. The doors 456 of the bomb bay door assembly 438 can proceed downward into the interior chamber 466 of the spacer 460, without interfering with the heated auger 42. Thus, material that falls through the interior chamber 448 of the bomb bay door assembly 438 can fall through the internal chamber 466 of the spacer 460 and into the heated auger 42.

[0083] F. Heated Auger.

[0084] The apparatus 10 (FIG. 20) further comprises heated auger 42. Heated auger 42 comprises inlet 472, jacket 474, base plate 476, outlet 478, motor 479, and end cap 548. Inlet 472 comprises top flange 480 and side walls 482. Top flange 480 comprises apertures 484. Apertures 484 match apertures 470 of the bottom platform 464 of the bomb bay door assembly 438, to allow the heated auger 42 to fixedly connect to the bomb bay door assembly 438. The shredded material can thus travel through spacer 460 into the inlet 472 of the heated auger 42. One side wall 482 comprises an aperture 486 and the other comprises an aperture 486'. Inlet 472 has an open bottom to allow the material to enter into chamber 500. One aperture 486 can be connected to piping leading to thermocouple 698, then to pressure transducer 700, and then to relief valve 702, which can discharge to atmosphere. Thermocouple 698 and pressure transducer 700 provide temperature data to the programmable logic controller 68. The other aperture 486' can be connected to piping leading to valve 950, which programmable logic controller 68 controls, and piping from valve 950 leads to boiler 678. Thus, valve 950 controls the introduction of steam from boiler 678 into heated auger 42 via aperture 486.

[0085] Jacket 474 (FIGS. 20 and 21) comprises inlet opening 488, internal surface 490, external surface 492, shaft 494, screw blade 496, aperture 498, chamber 500, chamber 502, drain 504, and attachment plate 508. In use, shredded material falls from the bomb bay door assembly 438, through the inlet opening 488 and into chamber 500. The volume between internal surface 490 and external surface 492 is chamber 502. Aperture 498 allows steam to access into chamber 502. Aperture 498 is connected to piping in communication with valve 704, relief valve 952, pressure reducing valve 954, and then boiler 678. Programmable logic controller 68 controls valve 704. In use, boiler 678 generates steam, pressure reducing valve 954 reduces the pressure of the steam, and valve 704 controls the introduction of steam into aperture 498 then chamber 502. Chamber 502 is thus heated and, via conduction, chamber 500 and the contents (shredded material) of chamber 500 are heated as well. Heating the internal surface 490 prevents the formation of cold spots, which could prevent sterilization of material touching internal surface 490. Steam that condenses into liquid can leave chamber 502 via drain 504 (through gravity force). Drain 504 communicates by piping with drain 632. A steam trap (not shown) could be placed between drain 504 and drain 632 to prevent steam from existing chamber 502 via drain 504. Relief valve 952 is set to relieve pressure within chamber 502 to maintain a maximum pressure within chamber 502 of 14.8 psig. Attachment plate 508 comprises apertures 510.

[0086] Outlet 478 comprises base plate 512, stepped attachment plate 522, attachment flange

526, bottom base flange 534, and open bottom 538. Stepped attachment plate 522 comprises an aperture (not shown) to allow drive shaft 532 to access shaft 494, and apertures (not shown) to allow connection to base plate 506. Base plate 512 comprises apertures (not shown) to match apertures 510 and allow connection to attachment plate 508. Attachment flange 526 comprises apertures 528, to allow attachment of attachment flange 526 to stepped attachment plate 522, via apertures (not shown). Bottom base flange 534 comprises apertures 536. Apertures 536 allow for the attachment of outlet 478 to the discharge chamber 558 (described below).

[0087] Motor 479 comprises base plate 506 and drive shaft 532. Base plate 506 comprises a stepped base 516 with apertures that match apertures of attachment plate 522, to allow for attachment thereto. Motor 479 turns drive shaft 532. Drive shaft 532 is placed through an aperture of stepped attachment plate 522. The other end of drive shaft 532 is connected to shaft 494. Thus, rotation of drive shaft 532 by the motor 479 causes rotation of shaft 494. A mechanical shaft seal can surround the shaft 494 between the base plate 506 and the stepped attachment plate 522. Rotation of shaft 494 causes rotation of screw blade 496, which acts as an Archimedes screw, causing the shredded material to travel from the inlet opening 488, through the chamber 500, and out the open bottom 538 of the outlet 478. Programmable logic controller 68 controls the operation of motor 479.

[0088] Base plate 476 comprises outer recess 539, inner recess 540, apertures 542, and aperture 544. Outer recess 539 accepts external surface 492. Inner recess 540 accepts internal surface 490. Apertures 542 allow the heated auger 42 to attach to the frame 606. End cap 548 comprises apertures 550. Apertures 550 allow for the connection of end cap 548 to base plate 476. End cap 548 further comprises slot 552, into which an O-ring can be placed. End cap 548 supports Teflon pads 554. Teflon pads 554 act as a bearing for support shaft 556. Support shaft 556 is attached to shaft 494.

[0089] G. Discharge chamber.

[0090] Discharge chamber 558 (FIG. 22) comprises top attachment plate 560, shield 566, and actuator 576. Top attachment plate 560 comprises apertures 562 and inlet 564. Apertures 562 match apertures 536 of the bottom base flange 534 of the outlet 478, to allow attachment of the outlet 478 to the discharge chamber 558. Actuator 576 is attached to arm 570. Thus, the actuator 576 manipulates the arm 570, causing to the arm 570 to extend away from or back towards the actuator 576. Arm 570 comprises fingers 572, which comprise apertures 574. Shield 566 comprises an aperture to match apertures 574 of the fingers 572 and thus allows for the attachment of the shield 566 to the arm 570, such as with a bolt. Thus, the actuator 576 manipulates the arm 570 and thereby manipulates the shield 566 causing the shield 566 to close inlet 564 or open inlet 564. Shield 566 moves within track 586 within each guide 584. Actuator 576 further comprises flange 578 with aperture 580, which allows the attachment of actuator 576 to frame 582.

[0091] Discharge chamber 558 further comprises spacer 590, which forms chamber 588, and outlet 602. The outlet 602 can be opened or closed via manipulation of shield 591. Shield 591 is attached to arm 592. Arm 592 is attached to actuator 594. Actuator 594 is attached to frame 596. The movement of shield 591 is guided by track 600 of each guide 598. Spacer 590 comprises aperture 604 and aperture 708. Aperture 604 communicates via piping with valve 706 and then to the drain 632. See FIG. 9C. Programmable logic controller 68 controls valve 706, actuator 576, and actuator 594. Aperture 708 allows access for a temperature gauge and pressure transducer 718, which communicates with programmable logic controller 68.

[0092] H. Control Center 714.

[0093] The apparatus 10 (FIG. 1) further comprises control center 714. The control center

714 houses the programmable logic controller 68, start button 30, and touch-screen display 716. The touch-screen display 716 can display real-time operating parameters (such as pressures, temperatures, and components activated). The programmable logic controller 68 can send operational data to a recording source, such as a disc, and can communicate with other process control equipment. A cover (not shown) can cover the apparatus, allowing access at the material inlet and outlet points and for the control center 714.

[0094] Within the control center 714, there can be an alarm screen for malfunctions. The alarm screen can tell the user what to do to fix the malfunction. The control center 714 can comprise a password system that permits the user to override the programmable logic controller 68 and thereby allow the user to test individual components of the apparatus 10 and steps of the methods described below. The control center 714 can comprise memory to record data, such as the various temperatures and pressures that are relayed to the programmable logic controller. For example, the memory can record the temperatures and pressures in increments of between thirty seconds and two minutes. The control center 714 can comprise a modem to allow a user to access and manipulate the programmable logic controller 68 remotely. The control center 714 can comprise a printer to print the data that the memory acquired.

[0095] 2. Method of Using First Embodiment.

[0096] A. Loading of Feed Hopper.

[0097] A method of using the first embodiment is herein described. A user obtains regulated medical waste and/or confidential documents to dispose. The user opens interlocked door 16 of the feed hopper 14. The opening of the interlocked door 16 causes projection 176 of limit switch activator 172 to release switch 20. Switch 20 signals the programmable logic controller 68 that the interlocked door 16 is opening. The programmable logic controller 68 ensures that shield 591 of discharge chamber 558 is closed (so as to close outlet 602) and shield 566 is open, by manipulating actuators 576 and 594; and that doors 456 of the bomb bay door assembly 438 are in the closed position to form a seal, by manipulating actuators 696. The programmable logic controller 68 then causes valve 640 (FIGS. 9A-9C) to open and blower 652 to activate. The activation of blower 652 creates a negative pressure within the inner chamber 296 of feed hopper 14 and thereby draws air from the atmosphere into the inner chamber 296 of feed hopper 14, the air then proceeding through aperture 304 of feed hopper 14, through piping (opened by valve 640), through HEPA filter 650, and out to the atmosphere.

[0098] The user then places the regulated medical waste into the inner chamber 296 of the feed hopper 14. The regulated medical waste can rest upon the surface of flexible covers 710 and 712, above the integral shredder 36 or directly on the cutter blades 342 and 360. The user then closes the interlocked door 16. The user rotates handle 28 and, thus, causes the lock end 268 of the lock rods 266 to enter into aperture 294 of lock plates 290 around the door well 288 of the feed hopper 14. The interlocked door 16 cannot then open without user involvement. The interlocked door 16 being in the closed position causes projection 176 of limit switch activator 172 to push against switch 20. Switch 20 then sends a signal to the programmable logic controller 68 that the interlocked door 16 is in the closed position.

[0099] B. Start Button, Locking Door, and Creation of Negative Pressure.

[00100] The user then can press the start button 30. Pressing the start button 30 informs the programmable logic controller 68 to begin processing the regulated medical waste. The programmable logic controller 68 causes pin 906 to extend from air cylinder 908 and thus externally locks interlocked door 16 to prevent a user from inadvertently opening door 16 while the apparatus 10 was active. The programmable logic controller 68 causes valve 640 to close and blower 652 to deactivate. Programmable logic controller 68 activates vacuum pump 668, by causing valves 670 and 671 to open. Opening of valves 670 and 671 allows water to flow from water supply 638, through valve 670, through the vacuum pump 668 (creating a vacuum leading to aperture 306, as discussed more below), through valve 671 and out to drain 632. Simultaneously with the opening of valves 670 and 671, programmable logic controller 68 causes valve 666 to open. Opening of valve 666 allows water to travel from water supply 638, through valve 666, through heat exchanger 664, and out to drain 632. Simultaneously with the opening of valves 670, 671, and 666, programmable logic controller 68 causes valve 660 to open. The creation of vacuum in vacuum pump 668 thus draws the gaseous contents of inner chamber 296 of feed hopper 14, through aperture 306, through HEPA filter 662, through heat exchanger 664, through vacuum pump 668, through gas/liquid separator 672, and then gas is vented to the atmosphere, while liquid is discharged to drain 632. Separator 672 can have two drain levels, one of which is in series with the outlet to vent and the other of which near the bottom to allow draining via gravity. The creation of this vacuum in inner chamber 296 evacuates air and other gases and allows injected steam (discussed below) to more effectively penetrate the inserted controlled medical waste. Drawing the gaseous contents of inner chamber 296 of feed hopper through heat exchanger 664 allows gaseous contents to condense into liquid form, if possible, at the particular temperature and pressure of the heat exchanger 664. For example, the heat exchanger 664 could condense water vapor present in the regulated medical waste into liquid water. The programmable logic controller 68 continues to allow such until pressure transducer 634 informs the programmable logic controller 68 that the pressure within the inner chamber 296 of the feed hopper 14 is negative 5 psig (or some other negative preset pressure). (Again, the doors 456 of the bomb bay door assembly 438 are in the closed position, to form a seal and allow the negative pressure to occur.) At that pressure, the programmable logic controller 68 causes valves 670, 671, 666, and 660 to close and thus no more gaseous contents from the inner chamber 296 of feed hopper 14 is drawn out.

[00101] C. Heating of Material and Pressurization of Feed Hopper and Heated

Auger.

[00102] Programmable logic controller 68 then causes valve 676 (FIG. 9C) to open and valve

680 to open. Boiler 678, which (like most steam sources) is typically always already activated, transforms water from water supply 638 into steam and pushes the steam through valve 676, through aperture 674, and into the inner chamber 296 of feed hopper 14. In addition, boiler 678 pushes steam through valve 680, and through aperture 452 of bomb bay door assembly 438. The introduction of steam into the inner chamber 296 of feed hopper 14 via apertures 674 and 452 has the effect of raising the pressure within the inner chamber 296 of feed hopper 14. The steam heats the regulated waste material and/or confidential documents, from both above and below. Boiler 678 will keep supplying steam into the inner chamber 296 of the feed hopper 14 and into the bomb bay door assembly 438 until (a) thermocouple 636 informs the programmable logic controller that the temperature within the inner chamber 296 has reached 248 degrees Fahrenheit, or (b) pressure transducer 634 or pressure transducer 700 reaches 14.8 psig. When either of those thresholds is met, the programmable logic controller 68 causes valves 676 and 680 to close. Relief valve 656 is set to release pressure at 14.8 psig and greater, to prevent the pressure within internal chamber 296 of feed hopper 14 from exceeding 14.8 psig.

[00103] Simultaneously, after the user presses the start button 30, programmable logic controller 68 opens valve 950 to allow steam from boiler 678 to enter into chamber 500 of heated auger 42 via aperture 486'. Programmable logic controller 68 turns off valve 950, when (a) thermocouple 698 informs the programmable logic controller that the temperature within the chamber 500 has reached 248 degrees Fahrenheit, or (b) pressure transducer 700 reaches 14.8 psig. At this point, the pressure and temperature on both sides of the bomb bay doors are equalized.

[00104] D. Opening of Bomb Bay Doors and Shredding of Material.

[00105] Now that pressure and temperature on both sides of bomb bay doors 456 are equal, programmable logic controller 68 causes the bomb bay doors 456 to open, motors 336 and 338 of the integral shredder 36 to activate, and actuators 382 and 408 to activate. Actuators 382 and 408 operate in a cyclical manner to continuously push and pull respective shafts 384 and 410, which in turn causes pushers 364 and 366 to flap continuously and cyclically towards and away from cutter blades 342 and 360. The initial movement of pushers 364 and 366 away from cutter blades 342 and 360 causes the regulated medical waste to drop towards the cutter blades 342 and 360 (if the material has been initially placed on flexible covers 710 and 712 rather than cutter blades 342 and 360). The successive movements of pushers 364 and 366 push the regulated medical waste towards the cutter blades 342 and 360. The cutter blades 342 and 360 shred the regulated medical waste. The cutter blades 342 and 360 continue to shred the regulated medical waste until the regulated medical waste is shredded into pieces sufficiently small to fall through the holes 426 of screen 422 and through the interior chamber 448 of bomb bay door assembly 439 and into heated auger 42 (as described below). The motors 336 and 338 continue to operate until the motors 336 and 338 signal to the programmable logic controller 68 that motors 336 and 338 are drawing a relatively low amperage (because the motors 336 and 338 are easily rotating cutter blades 342 and 360, because there is no more regulated medical waste and/or documents to be shredded). At that relatively low amperage, programmable logic controller 68 causes motors 336 and 338 to deactivate and actuators 382 and 408 to deactivate. Had the motors 336 and 338 communicated a relatively high amperage to the programmable logic controller 68 (thus signifying that regulated medical waste had clogged and prevented the rotation of cutter blades 342 and 360), then the programmable logic controller 68 causes motors 336 and 338 to operate in reverse direction for a set period of time (to clear the stuck regulated medical waste from the cutter blades 342 and 360) then, after that, resume operation of motors 336 and 338 in the normal, shredding direction. [00106] The regulated medical waste and/or documents, now shredded, have fallen through the internal chamber 466 of spacer 460, through inlet 472 of the heated auger 42, and around shaft 494 and rotating screw blade 496 within chamber 500. Programmable logic controller then causes the pair of actuators 696 to close doors 456 of bomb bay door assembly 438 so as to form a seal.

[00107] E. Cooling Feed Hopper and Progression of Material Through Heated

Auger.

[00108] Two series of events then simultaneously occur— one occurring relative to the feed hopper 14 and one occurring relative to the heated auger 42 and discharge chamber 558.

[00109] i. Cooling and Depressurization of Feed Hopper for Reloading.

[00110] As for the events occurring relative to the feed hopper 14, the programmable logic controller 68 causes valves 631 and 630 (FIG. 9A) to open, to allow cool water from the water supply 638 to proceed through cooling coil 316 in the inner chamber 296 of feed hopper 14. The cool water traveling through the cooling coil 316 helps cool the inner chamber 296 of the feed hopper 14 and condense vapor therein. The water from the cooling coil exits to drain 632. When pressure transducer 634 informs programmable logic controller 68 that the pressure within inner chamber 296 of feed hopper 14 has dropped to approximately 6 psig, the programmable logic controller 68 closes valves 631 and 630 and, thus, stops the flow of cooling water through cooling coil 316. In addition, when the pressure transducer 634 informs programmable logic controller 68 that the pressure within inner chamber 296 has dropped to approximately 6 psig, the programmable logic controller 68 opens valves 670 and 671 to allow water from water supply 638 to flow through valve 670, through vacuum pump 668, through valve 671, and out to drain 632. Simultaneously, programmable logic controller 68 opens valve 660. The flow of water through vacuum pump 668 causes the gaseous contents of inner chamber 296 of feed hopper 14 to flow through aperture 306, through valve 660, through HEPA filter 662, through heat exchanger 664, through vacuum pump 668, through separator 672, and to vent (for separated gas) or drain 632 (for separated liquid). Simultaneously, programmable logic controller 68 opens valve 666, causing cooling water from water supply 638 to travel through valve 666 and into heat exchanger 664 (to cool the gaseous contents described in the preceding sentence) and out to drain 632. When pressure transducer 634 informs programmable logic controller 68 that the pressure within inner chamber 296 has dropped to approximately 1 psig (atmospheric pressure), then programmable logic controller 68 closes valves 670, 671, 660, and 666. Thereafter, programmable logic controller opens valve 640, initiates vacuum blower 652, and opens valve 646. The blower 652 causes the gaseous contents of inner chamber 296 to proceed through aperture 304, through valve 640, and into condenser piping assembly 642. Cooling water from water supply 638 travels through valves 631 and 646 and through spray nozzles 644 to cool the gaseous contents (thereby condensing any remaining steam) within the condenser piping assembly 642. The liquid from the condenser piping assembly travels to drain 632, while the blower 652 causes the gaseous contents to travel through the HEPA filter 650, through the blower 652 and to exhaust 654. The feed hopper 14 is thus cooled and gaseous contents are evacuated. The blower 652 remains active until the user presses the start button 30 for the next cycle or turns off the apparatus 10.

[00111] ii. Heating Jacket and Incremental Progression of Material.

[00112] As for the events concerning the heated auger 42 and discharge chamber 558, programmable logic controller 68 then opens valve 704. Boiler 678 thus causes steam to travel from boiler 678, through reducing valve 954 (to reduce the steam pressure to approximately 14.8 psig), through valve 704, through aperture 498 of the heated auger 42, and into chamber 502 of jacket 474 of heated auger 42. The steam heats the internal surface 490 of jacket 474 to 248 degrees Fahrenheit to prevent cold spots. The chamber 500 of the heated auger 42 has already been heated to 248 degrees Fahrenheit (as described above). The chamber 500 is still sealed at this point via the closed doors 956 of the bomb bay door assembly 438 and the closed shield 591 of discharge chamber 558. Programmable logic controller 68 will turn on valve 950 again when (a) thermocouple 698 informs the programmable logic controller that the temperature within the chamber 500 has reached 246 degrees Fahrenheit, or (b) pressure transducer 700 reaches 14.4 psig. In addition, to the extent that the pressure within the chamber 500 is greater than 14.8 psig, then the gaseous contents within chamber 500 flow through relief valve 702, which allows venting to the atmosphere, until the pressure drops to 14.8 psig. The point is that the programmable logic controller 68 opens/closes the valve 950 accordingly to keep the temperature within the chamber 500 at 248 degrees Fahrenheit.

[00113] The programmable logic controller 68 then causes motor 479 to turn shaft 494. The screw blade 496 acts as Archimedes screw, pushing the shredded regulated medical waste through the heated auger 42 towards outlet 478. The programmable logic controller 68 does not initially cause the heated waste proceed all the way to outlet 478 but only partially— a length sufficient to make room for new waste falling from shredder 36. In other words, the user can add additional loads of regulated medical waste into feed hopper 14 while the heated auger 14 is still sterilizing previous loads of waste.

[00114] F. Depressurization of Chamber and Dumping of Material.

[00115] The programmable logic controller 68 then causes shield 566 to close via actuator 576 and valve 706 to open, which allows the chamber 588 of discharge chamber 558 (and the shredded contents therein, if any) to vent to drain 632 via aperture 604. Pressure transducer 718 informs the programmable logic controller 68 of the pressure within chamber 588. When the pressure transducer 718 informs the programmable logic controller 68 that the pressure within chamber 588 is approximately equal to atmospheric pressure, then the programmable logic controller 68 causes actuator 594 to open shield 591 (by retracting arm 592). The shredded regulated medical waste, if any, thus falls into a discharge device (such as a cart or compactor) and can be disposed of like regular waste; that is, the apparatus 10 has fully sterilized and shredded the regulated medical waste and/or documents into unidentifiable and clean pieces. After a set time, the programmable logic controller 68 causes actuator 594 to close shield 591, actuator 576 to open shield 566, and to close valve 706.

[00116] G. Continuation of Material Through Heated Auger and Discharging.

[00117] If the user does not add additional regulated medical waste into the feed hopper 14 and press the start button 30 within a set period of time (e.g., thirty minutes), then the programmable logic controller 68 causes motor 479 to rotate shaft 494 for a short period of time, so that any material remaining in the heated auger 42 does not adhere permanently to the inner surface 490 and the material is incrementally advanced toward outlet 478 of heated auger 42. Step F, above, the closing of shield 566, depressurization of discharge chamber 558, opening of shield 591, closing of shield 591, and opening of shield 566, occurs after each rotation event of shaft 494, to dump any material that may have fallen into discharge chamber 558. The programmable logic controller 68 will repeat the activation of motor 479 periodically. The motor 479 rotates sufficiently slowly to allow the preheated shredded regulated medical waste to maintain heat for a period of time and thereby becoming sterilized. Eventually, the screw blade 496 pushes the shredded (and now sterilized) regulated medical waste and/or documents out the open bottom 538 of outlet 478. A batch of medical waste should reside within the heated auger for between thirty and ninety minutes, depending on the volume of the batch, in order to become sufficiently sterilized. The shredded regulated medical waste thus falls onto shield 591 and into chamber 588 surrounded by spacer 590 of discharge chamber 558, as explained above. [00118] 3. A Second Embodiment.

[00119] In a second embodiment, apparatus 10 of the first embodiment is altered in several ways. First, as discussed in greater detail below, a gated device such as horizontal slide gate unit 720 is placed between the feed hopper 14 and the integral shredder 36 and acts as the first retractable seal. Second, the doors 456 and shafts 454 of the bomb bay door assembly 438 are removed and the apertures 450 are capped. Third, the outlet 478 of the heated auger 42 is replaced with outlet 722. Fourth, the discharge chamber 558 is replaced with discharge chamber 724, with inflatable butterfly valve 836 and inflatable butterfly valve 840 acting as the second and third retractable seals respectively. Apparatus 10 of the second embodiment is otherwise the same as the apparatus 10 of the first embodiment.

[00120] a. Horizontal Slide Gate Unit 720.

[00121] The horizontal slide gate unit 720 (FIG. 23) is placed between the feed hopper 14 and the integral shredder 36, both of which are described above in connection with the first embodiment. The horizontal slide gate unit 720 comprises lower enclosure 726 (FIGS. 24 and 25), cover 728, gate 730, open bottom 732, seal box 734, wiper mount 736, seal plate 738, motor 740, silicone wiper 742, and motor mount 806. The lower enclosure 726 comprises lip 746 (FIG. 25), back wall 750, bottom 752, side wall 754, side wall 756, lip 758, spacer 760, lip 762, lip 764, and apertures 766. Lip 746 comprises apertures that line up with apertures 748 of cover 728, to allow cover 728 to attach to lower enclosure 726. Back wall 750, bottom 752, side wall 756, and side wall 754, along with cover 728, provide housing for gate 730 and associated parts (discussed below). Lip 762 comprises apertures 766. Lip 758 is contiguous with lip 762 and allows for connection of the lower enclosure 726 to the top surface 324 of the integral shredder 36, such as by placing bolts through apertures 766 of the lower enclosure 726 and then through matching apertures 326 of top surface 324 of the integral shredder 36. Spacer 760 provides room for the gate 730 maneuver. Lip 764 comprises apertures to allow the lower enclosure 726 to attach to seal plate 738 via apertures 768 of the seal plate 738. Lower enclosure 726 has an opening bounded by the continuous surface of lip 762 and lip 758, to allow material to fall through that opening and into the integral shredder 36. Side wall 754 has an aperture to allow shaft 780 to enter into the interior of the lower enclosure 726. Side wall 756 has a matching aperture to allow shaft 780 to exit the interior of the lower enclosure 726. [00122] Cover 728 comprises seal lip 770 and apertures 771. Apertures 771 line up with apertures (not shown) in the seal plate 738 and allow connection of the cover 728 to the seal plate 738.

[00123] Gate 730 is a wedge-shaped piece of material that is sufficiently wide and long to completely block open bottom 732 of the horizontal slide gate unit 720, when gate 730 is in closed position. The bottom of gate 730 is attached to rack 772. Rack 772 comprises teeth 774. Teeth 774 are spaced and sized to mate with teeth 776 of pinion 778. Thus, rotation of pinion 778 causes rack 772 to move and thus gate 730 to move. Pinion 778 is attached to shaft 780 and rotation of shaft 780 causes pinion 778 to rotate. The other end of shaft 780 is attached to motor 740 and motor causes shaft 780 to rotate. Programmable logic controller 68 controls the operation of motor 740. The non-motor end of shaft 780 protrudes through side wall 756 of the lower enclosure 726 and is surrounded by bearings housed in a bearing cap (not shown). The bearing cap is affixed to the side wall 756 of the lower enclosure 726. A pair of spaced-apart Teflon-covered guide rails 784 are attached to side wall 736 and another matching pair are attached to side wall 754 in the same manner and on the same plane as guide rails 784. Teflon-covered guide rails 784 are spaced sufficiently apart to form a slot 786. Gate 730 comprises a slot lip (not shown) that runs along the bottom of the gate 730. The slot lip is positioned within slot 786, so that gate 730 rides along the Teflon- covered guide rails 784 as motor 740 rotates the pinion 778.

[00124] Seal box 734 is attached to side wall 754. Seal box 734 covers a shaft seal. The shaft seal acts to eliminate any lack of seal caused by placing shaft 780 through the aperture in side wall 754.

[00125] Wiper mount 736 is attached to the inside of the feed hopper 14 near the open bottom

318 of the feed hopper 14, along all four sides of the feed hopper 14. Silicone wipers 742 are mounted onto the wiper mount 736 and extend downward towards open bottom 732.

[00126] Seal plate 738 comprises apertures 768 (FIGS. 24 and 26), apertures 788, slots 790, back side 794, groove 796, and opening 798. As explained above, apertures 768 allow the seal plate 738 to attach to the lip 764 of the lower enclosure 726. Apertures 788 match apertures within bottom plate 320 of the feed hopper 14, to allow attachment of the feed hopper 14 to the seal plate 738. Slots 790 provide a means to attach seal 792 to seal plate 738 (as explained below). A groove 796 is placed into the back side 794 around the opening 798 of the seal plate 738. The groove 796 provides a seat for seal 792. [00127] Seal 792 comprises a main body 800 (FIG. 27) and extensions 802. Main body 800 is sized to sit partially within groove 796 (FIG. 26A) of seal plate 738. The middle of each extension 802 forms an arrowhead 804, which is wider than the rest of the extension and resembles an arrowhead. The extensions 802 (FIG. 26B) are placed through slots 790 of the seal plate 738 and the arrowhead 804 of each extension 802 expands on the other side of the seal plate 738, to keep the main body 800 of the seal 792 secure within the groove 796 of the seal plate 738.

[00128] Motor mount 806 (FIG. 28) comprises motor attachment zone 810, feed hopper attachment zone 816, and shredder attachment zone 818. Motor attachment zone 810 provide apertures (not shown) to allow the motor casing (with matching apertures) to attach to the motor mount. In addition, motor attachment zone provides an aperture (not shown) through which shaft 780 can extend. Feed hopper attachment zone 816 comprises apertures 828 that are located to match apertures through the bottom plate 320 of the feed hopper 14, to allow attachment of the motor mount 806 to the feed hopper 14. Shredder attachment zone 818 comprises apertures (not shown) to allow the attachment of motor mount 806 to the integral shredder 36.

[00129] First sensor flange 812 is attached to spacer 760 and comprises an aperture (not shown) in which proximity sensor 820 can mount. Casing 956 extends from spacer 760, between the proximity sensor 820 and spacer 760. Casing 956 houses plunger 958 and an aperture through which plunger 958 can extend or retract. Plunger 958 comprises head 960, which resides on the outside of casing 956. The other end of plunger 958 is seated in seat 962. A spring 964 is placed within casing 956 between the plunger 958 end of the seat 962 and the end of casing 958 nearest head 960. A rod 966 is seated in the other end of seat 962. The non-seated end of rod 966 protrudes through an aperture in spacer 760. A lip 968 extends down from the edge of the gate 730 nearest most spacer 760. As motor 740 rotates shaft 780 in one direction, gate 730 moves towards spacer 760. Eventually, lip 968 of gate 730 will run into rod 966 and push rod 966 further into casing 956 and, thus, cause plunger 958 to push head 960 towards proximity sensor 820. When head 960 is close enough to proximity sensor 820, proximity sensor 820 recognizes head 960 and signals such to programmable logic controller 68. Programmable logic controller 68 can then signal motor 740 to stop.

[00130] Second sensor flange 814 is attached to back wall 750 of lower enclosure 726 and comprises aperture (not shown) in which proximity sensor 744 can mount. Casing 970 extends from back wall 750, between the proximity sensor 744 and back wall 750. Casing 970 houses plunger 972 and an aperture through which plunger 972 can extend or retract. Plunger 972 comprises head 974, which resides on the outside of casing 970. The other end of plunger 972 is seated in seat 976. A spring 978 is placed within casing 970 between the plunger 972 end of the seat 976 and the end of casing 970 nearest head 974. A rod 980 is seated in the other end of seat 976. The non-seated end of rod 980 protrudes through an aperture in back wall 750. Gate 730 comprises back edge 982. As motor 740 rotates shaft 780 in the opposite direction described in the preceding paragraph, gate 730 moves towards back wall 750. Eventually, back edge 982 of gate 730 will run into rod 980 and push rod 980 further into casing 970 and, thus, cause plunger 972 to push head 974 towards proximity sensor 744. When head 974 is close enough to proximity sensor 744, proximity sensor 744 recognizes head 974 and signals such to programmable logic controller 68. Programmable logic controller 68 can then signal motor 740 to stop.

[00131] In use, when gate 730 is in closed position, the pressure within integral shredder 36 will at times be higher than the pressure within feed hopper 14, thus causing gate 730 to push up towards feed hopper 14. The upward pressure force forces gate 730 to compress main body 800 of seal 729, forming a seal so that pressure is not released into feed hopper 14. The horizontal slide gate unit 720 can take a variety of other forms, so long as the horizontal slide gate unit 720 is capable of forming a seal between feed hopper 14 and integral shredder 36 when closed yet capable of allowing material to drop from feed hopper 14 into integral shredder 36 when open.

[00132] b. Bomb Bay Door Assembly Without Bomb Bay Doors.

[00133] In the second embodiment, door assembly 438 remains positioned between the integral shredder 36 and spacer 460, as in the first embodiment discussed above. However, in this second embodiment, shafts 454, doors 456, and actuator assemblies 684 are not utilized and are removed. Apertures 451 are therefore capped and sealed. (Alternatively, the space occupied by the bomb bay door assembly 438 and spacer 460 can be eliminated entirely, so that the base 420 of integral shredder 36 attaches directly to top flange 480 heated auger 42. In such a design, however, aperture 452 must remain to allow for the introduction of steam between the curved mesh 424 of the integral shredder 36 and the inlet 472 of the heated auger 42.) [00134] c. Outlet of Heated Auger.

[00135] In this second embodiment, outlet 722 (FIG. 29) replaces outlet 478 for connection to the heated auger 42. Base plate 512, stepped attachment plate 522, and attachment flange 526 of outlet 722 remain the same as those components for outlet 478. However, in the second embodiment, bottom base flange 830 replaces bottom base flange 534 of the first embodiment. Bottom base flange 830 is circular and chute 832 is cylindrical (as opposed to rectangular in the first embodiment). Bottom base flange 830 comprises apertures 834, to allow attachment to first inflatable butterfly valve 836 of discharge chamber 724 (discussed below).

[00136] d. Discharge Chamber.

[00137] In this second embodiment, discharge chamber 724 replaces discharge chamber 558 of the first embodiment. Discharge chamber 724 comprises first inflatable butterfiy valve 836, spacer 838, and second inflatable butterfly valve 840. First inflatable butterfly valve 836 and second inflatable butterfly valve 840 need not be inflatable butterfly valves but, rather, can be any kind of valve, damper, or other structure that can open and close and form a seal in the closed position. In this embodiment, first inflatable butterfly valve 836 comprises motor 842 and housing 844. Motor 842 is controlled by programmable logic controller 68. Housing 844 comprises apertures (not shown) that match apertures 834 of the bottom base flange 830 of the outlet 722 of heated auger 42. Housing 844 houses an inflatable balloon (not shown). Motor 842 manipulates butterfly valve (not shown), either closing access to spacer 838 or allowing access to spacer 838. When butterfly valve is in closed position, the inflatable balloon inflates and forms a seal around butterfly valve. Spacer 838 comprises a hollow interior, first base 846, and second base 848. First base 846 comprises apertures (not shown) to allow attachment to housing 844 of the first inflatable butterfly valve 836. Second base 848 comprises apertures 850. Apertures 850 allow attachment of spacer 838 to housing 852 of second inflatable butterfly valve 840. Second inflatable butterfly valve 840 additionally comprises motor 854, inflatable balloon (not shown) and butterfly valve (not shown). Programmable logic controller 68 manipulates motor 854 and thus manipulates the movement of butterfiy valve and inflatable balloon. [00138] 4. Method of Using Second Embodiment.

[00139] A. Loading of Feed Hopper.

[00140] A method of using the second embodiment is herein described. A user obtains regulated medical waste and/or confidential documents to sterilize and dispose. The user opens interlocked door 16 of the feed hopper 14. The opening of the interlocked door 16 causes projection 176 of limit switch activator 172 to release switch 20. Switch 20 signals the programmable logic controller 68 that the interlocked door 16 is opening. The programmable logic controller 68 manipulates motor 740 to ensure that gate 730 of horizontal slide gate unit 720 is in the closed position so as to block open bottom 732 and form a seal between the feed hopper 14 and the integral shredder 36. The programmable logic controller 68 depowers motor 740 when proximity sensor 820 senses the proximity of head 960 and informs programmable logic controller 68 of such. The programmable logic controller 68 additionally ensures that the valve of the second inflatable butterfly valve 840 (FIGS. 9A-9C) is closed so as to close the outlet) by manipulating motor 854 and, further, that the valve of the first inflatable butterfly valve 836 is open by manipulating motor 842. The programmable logic controller 68 then causes valve 640 to open and blower 652 to activate. The activation of blower 652 creates a negative pressure within the inner chamber 296 of feed hopper 14 and draws air from the atmosphere, into the inner chamber 296 of feed hopper 14, the air then proceeding through aperture 304 of feed hopper 14, through piping (opened by valve 640), through HEPA filter 650, and out to the atmosphere.

[00141] The user places the regulated medical waste into the inner chamber 296 of the feed hopper 14. The regulated medical waste can rest upon the surface of gate 730 of horizontal slide gate unit 720. The user then closes the interlocked door 16. The user rotates handle 28 and, thus, causes the lock end 268 of the lock rods 266 to enter into aperture 294 of lock plates 290 around the door well 288 of the feed hopper 14. The interlocked door 16 cannot then open without user involvement. The interlocked door 16 being in the closed position causes projection 176 of limit switch activator 172 to push against switch 20. Switch 20 then sends a signal to the programmable logic controller 68 that the interlocked door 16 is in the closed position.

[00142] B. Start Button, Locking Door, and Creation of Negative Pressure.

[00143] The user then can press the start button 30. Pressing the start button 30 informs the programmable logic controller 68 to begin processing the regulated medical waste. The programmable logic controller 68 causes pin 906 to extend from air cylinder 908 and thus externally locks interlocked door 16 to prevent a user from inadvertently opening door 16 while the apparatus 10 was active. The programmable logic controller 68 causes valve 640 to close and blower 652 to deactivate. Programmable logic controller 68 activates vacuum pump 668, by causing valves 670 and 671 to open. Opening of valves 670 and 671 allows water to flow from water supply 638, through valve 670, through the vacuum pump 668 (creating a vacuum force leading to aperture 306, as discussed more below), through valve 671 and out to drain 632. Simultaneously with the opening of valves 670 and 671, programmable logic controller 68 causes valve 666 to open. Opening of valve 666 allows water to travel from water supply 638, through valve 666, through heat exchanger 664, and out to drain 632. Simultaneously with the opening of valves 670, 671, and 666, programmable logic controller 68 causes valve 660 to open. The creation of vacuum in vacuum pump 668 thus draws the gaseous contents of inner chamber 296 of feed hopper 14, through aperture 306, through HEPA filter 662, through heat exchanger 664, through vacuum pump 668, through gas/liquid separator 672, and then gas is vented to the atmosphere, while liquid is discharged to drain 632. Separator 672 can have two drain levels, one of which is in series with the outlet to vent and the other of which near the bottom to allow draining via gravity. The creation of this vacuum in inner chamber 296 evacuates air and other gases and allows injected steam (discussed below) to more effectively penetrate the inserted controlled medical waste. Drawing the gaseous contents of inner chamber 296 of feed hopper through heat exchanger 664 allows gaseous contents to condense into liquid form, if possible, at the particular temperature and pressure of the heat exchanger 664. For example, the heat exchanger 664 could condense water vapor present in the regulated medical waste into liquid water. The programmable logic controller 68 continues to allow such until pressure transducer 634 informs the programmable logic controller 68 that the pressure with the inner chamber 296 of the feed hopper 14 is negative 5 psig (or some other negative preset pressure). (Again, gate 730 of the horizontal slide gate unit 720 is in the closed position to form a seal and allow the negative pressure to occur.) At that pressure, the programmable logic controller 68 causes valves 670, 671, 666, and 660 to close and thus no more gaseous contents from the inner chamber 296 of feed hopper 14 is drawn out.

[00144] C. Heating of Material and Pressurization of Feed Hopper and Auger.

[00145] Programmable logic controller 68 then causes valve 676 to open. Boiler 678, which

(like most steam sources) is typically always already activated, transforms water from water supply 638 into steam and pushes the steam through valve 676, through aperture 674, and into the inner chamber 296 of feed hopper 14. The introduction of steam into the inner chamber 296 of feed hopper 14 via aperture 674 has the effect of raising the pressure within the inner chamber 296 of feed hopper 14. Boiler 678 will keep supplying steam into the inner chamber 296 of the feed hopper 14 until (a) thermocouple 636 informs the programmable logic controller that the temperature within the inner chamber 296 has reached 248 degrees Fahrenheit, or (b) pressure transducer 634 reaches 14.8 psig. When either of those thresholds is met, the programmable logic controller 68 causes valve 676 to close. Relief valve 656 is set to release pressure at 14.8 psig and greater, to prevent the pressure within internal chamber 296 of feed hopper 14 from exceeding 14.8 psig.

[00146] Simultaneously, after the user presses the start button 30, programmable logic controller 68 opens valves 680 and 950 to allow steam from boiler 678 to enter into chamber 500 of heated auger 42 via aperture 486' of the heated auger 42 and aperture 452 of bomb bay door assembly 438 (or, if the bomb bay door assembly 438 has been totally removed, through aperture 452 placed somewhere between the curved mesh 424 of the integral shredder 36 and the inlet 472 of the heated auger 42). Programmable logic controller 68 turns off valve 704, when (a) thermocouple 698 informs the programmable logic controller that the temperature within the chamber 500 has reached 248 degrees Fahrenheit, or (b) pressure transducer 700 reaches 14.8 psig. At this point, the pressure and temperature on both sides of gate 730 of the horizontal slide gate unit 720 are equalized.

[00147] D. Opening of Gate 730 and Shredding of Material.

[00148] Now that pressure and temperature on both sides of gate 730 are equal, programmable logic controller 68 causes the gate 730 to open, motors 336 and 338 of the integral shredder 36 to activate, and actuators 382 and 408 to activate. Thus, the inserted medical waste and/or documents to fall into integral shredder 36. The programmable logic controller 68 opens gate 730 by activating motor 740 and causing it to rotate shaft 780 in the opposite direction as before. When proximity sensor 744 senses head 974, proximity sensor 744 communicates such to programmable logic controller 68, which in turn depowers motor 740. The gate 730 is then in the open position. Actuators 382 and 408 operate in a cyclical manner to continuously push and pull respective shafts 384 and 410, which in turn causes pushers 364 and 366 to flap continuously and cyclically towards and away from cutter blades 342 and 360. The successive movements of pushers 364 and 366 push the regulated medical waste towards the cutter blades 342 and 360. The cutter blades 342 and 360 shred the regulated medical waste. The cutter blades 342 and 360 continue to shred the regulated medical waste until the regulated medical waste is shredded into pieces sufficiently small to fall through the holes 426 of screen 422 and through the interior chamber 448 of bomb bay door assembly 439 and into heated auger 42 (as described below). The motors 336 and 338 continue to operate until the motors 336 and 338 signal to the programmable logic controller 68 that motors 336 and 338 are drawing a relatively low amperage (because the motors 336 and 338 are easily rotating cutter blades 342 and 360, because there is no more regulated medical waste and/or documents to be shredded). At that relatively low amperage, programmable logic controller 68 causes motors 336 and 338 to deactivate and actuators 382 and 408 to deactivate. Had the motors 336 and 338 communicated a relatively high amperage to the programmable logic controller 68 (thus signifying that regulated medical waste had clogged and prevented the rotation of cutter blades 342 and 360), then the programmable logic controller 68 causes motors 336 and 338 to operate in reverse direction for a set period of time (to clear the stuck regulated medical waste from the cutter blades 342 and 360) then, after that, resume operation of motors 336 and 338 in the normal, shredding direction.

[00149] The regulated medical waste and/or documents, now shredded, have fallen through the internal chamber 466 of spacer 460, through inlet 472 of the heated auger 42, and around shaft 494 and rotating screw blade 496 within chamber 500. Programmable logic controller then causes motor 740 to close gate 730 of horizontal slide gate unit 720 so as to form a seal.

[00150] E. Cooling Feed Hopper and Progression of Material Through Auger.

[00151] Two series of events then simultaneously occur— one occurring relative to the feed hopper 14 and one occurring relative to the heated auger 42 and discharge chamber 724.

[00152] i. Cooling and Depressurization of Feed Hopper for Reloading.

[00153] As for the events occurring relative to the feed hopper 14, the programmable logic controller 68 causes valves 631 and 630 (FIG. 9A) to open, to allow cool water from the water supply 638 to proceed through cooling coil 316 in the inner chamber 296 of feed hopper 14. The cool water traveling through the cooling coil 316 helps cool the inner chamber 296 of the feed hopper 14 and condense vapor therein. The water from the cooling coil exits to drain 632. When pressure transducer 634 informs programmable logic controller 68 that the pressure within inner chamber 296 of feed hopper 14 has dropped to approximately 6 psig, the programmable logic controller 68 closes valves 631 and 630 and, thus, stops the flow of cooling water through cooling coil 316. In addition, when the pressure transducer 634 informs programmable logic controller 68 that the pressure within inner chamber 296 has dropped to approximately 6 psig, the programmable logic controller 68 opens valves 670 and 671 to allow water from water supply 638 to flow through valve 670, through vacuum pump 668, through valve 671, and out to drain 632. Simultaneously, programmable logic controller 68 opens valve 660. The flow of water through vacuum pump 668 causes the gaseous contents of inner chamber 296 of feed hopper 14 to flow through aperture 306, through valve 660, through HEPA filter 662, through heat exchanger 664, through vacuum pump 668, through separator 672, and to vent (for separated gas) or drain 632 (for separated liquid). Simultaneously, programmable logic controller 68 opens valve 666, causing cooling water from water supply 638 to travel through valve 666 and into heat exchanger 664 (to cool the gaseous contents described in the preceding sentence) and out to drain 632. When pressure transducer 634 informs programmable logic controller 68 that the pressure within inner chamber 296 has dropped to approximately 1 psig (atmospheric pressure), then programmable logic controller 68 closes valves 670, 671, 660, and 666. Thereafter, programmable logic controller opens valve 640, initiates vacuum blower 652, and opens valve 646. The blower 652 causes the gaseous contents of inner chamber 296 to proceed through aperture 304, through valve 640, and into condenser piping assembly 642. Cooling water from water supply 638 travels through valves 631 and 646 and through spray nozzles 644 to cool the gaseous contents (thereby condensing any remaining steam) within the condenser piping assembly 642. The liquid from the condenser piping assembly travels to drain 632, while the blower 652 causes the gaseous contents to travel through the HEPA filter 650, through the blower 652 and to exhaust 654. The feed hopper 14 is thus cooled and gaseous contents are evacuated. The blower 652 remains active until the user presses the start button 30 for the next cycle or turns off the apparatus 10.

[00154] ii. Heating Jacket and Incremental Progression of Material.

[00155] As for the events concerning the heated auger 42 and discharge chamber 724, programmable logic controller 68 then opens valve 704. Boiler 678 thus causes steam to travel from boiler 678, through reducing valve 954 (to reduce the steam pressure to approximately 14.8 psig), through valve 704, through aperture 498 of the heated auger 42, and into chamber 502 of jacket 474 of heated auger 42. The steam heats the internal surface 490 of jacket 474 to 248 degrees Fahrenheit to prevent cold spots. The chamber 500 of the heated auger 42 has already been heated to 248 degrees Fahrenheit (as described above). The chamber 500 is still sealed at this point via the closed gate 730 of the horizontal slide gate unit 720 and the valve of the second inflatable butterfly valve 840 is closed of discharge chamber 724. Programmable logic controller 68 will turn on valve 950 again when (a) thermocouple 698 informs the programmable logic controller that the temperature within the chamber 500 has reached 246 degrees Fahrenheit, or (b) pressure transducer 700 reaches 14.4 psig. In addition, to the extent that the pressure within the chamber 500 is greater than 14.8 psig, then the gaseous contents within chamber 500 flow through relief valve 702, which allows venting to the atmosphere, until the pressure drops to 14.8 psig. The point is that the programmable logic controller 68 opens/closes the valve 950 accordingly to keep the temperature within the chamber 500 at 248 degrees Fahrenheit.

[00156] The programmable logic controller 68 then causes motor 479 to turn shaft 494. The screw blade 496 (FIGS. 20 and 29) acts as Archimedes screw, pushing the shredded regulated medical waste through the heated auger 42 towards outlet 722. The programmable logic controller 68 does not initially cause the heated waste proceed all the way to outlet 722 but only partially— a length sufficient to make room for new waste falling from shredder 36. In other words, the user can add additional loads of regulated medical waste into feed hopper 14 while the heated auger 14 is still sterilizing previous loads of waste.

[00157] F. Depressurization of Chamber and Dumping of Material.

[00158] The programmable logic controller 68 then causes valve of first inflatable butterfly valve 836 to close via motor 842 and valve 706 to open, which allows the chamber of discharge chamber 724 (and the shredded contents therein, if any) to vent to drain 632 via aperture 604. Pressure transducer 718 informs the programmable logic controller 68 of the pressure within chamber of discharge chamber 724. When the pressure transducer 718 informs the programmable logic controller 68 that the pressure within chamber of discharge chamber 724 is approximately equal to atmospheric pressure, then the programmable logic controller 68 causes motor 854 to open valve of second inflatable butterfly valve 840. The shredded regulated medical waste, if any, thus falls into a discharge device (such as a cart or compactor) and can be disposed of like regular waste; that is, the apparatus 10 has fully sterilized and shredded the regulated medical waste and/or documents into unidentifiable and clean pieces. After a set time, the programmable logic controller 68 causes motor 854 to close valve of second inflatable butterfly valve 840, motor 842to open valve of first butterfly valve 836, and to close valve 706.

[00159] G. Continuation of Material Through Auger and Discharging.

[00160] If the user does not add additional regulated medical waste into the feed hopper 14 and press the start button 30 within a set period of time (e.g., thirty minutes), then the programmable logic controller 68 causes motor 479 to rotate shaft 494 for a short period of time, so that any material remaining in the heated auger 42 does not adhere permanently to the inner surface 490 and the material is incrementally advanced toward outlet 722 of heated auger 42. Step F, above, the closing of valve of first inflatable butterfly valve 837, depressurization of discharge chamber 724, opening of valve of second inflatable butterfly valve 840, closing of valve of second inflatable butterfly valve 840, and opening of valve of first inflatable butterfly valve 837, occurs after each rotation event of shaft 494, to dump any material that may have fallen into discharge chamber 558. The programmable logic controller 68 will repeat the activation of motor 479 periodically. The motor 479 rotates sufficiently slowly to allow the preheated shredded regulated medical waste to maintain heat for a period of time and thereby becoming sterilized. Eventually, the screw blade 496 pushes the shredded (and now sterilized) regulated medical waste and/or documents out the open bottom 732 of outlet 722. The shredded regulated medical waste thus falls onto valve of second inflatable butterfly valve 840 and into chamber surrounded by spacer 838 of discharge chamber 724, as explained above.

[00161] 5. Accessory - cart dumper.

[00162] An accessory to both embodiments of apparatus 10 can be cart dumper 78 (FIGS. 30).

The user of apparatus 10 can use cart dumper 78 to help the user load regulated medical waste and/or confidential documents into the feed hopper 14. When a cart dumper 78 is used, it would be helpful to have the interlocked door 16 and door well 288 angled relative to the horizon rather than vertical as shown in FIG. 1.

[00163] Cart dumper 78 can comprise frame 80 and basket 102. Frame 80 comprises first vertical beam 856, second vertical beam 858, actuator 872, and horizontal beam 874. First vertical beam 856 and second vertical beam 858 form a track 860 in which carriage 862 can ride. Carriage 862 comprises vertical members 864, guide wheels 866, rotating shaft 868, and actuator 870. Guide wheels 866 are affixed to both vertical members 864. The guide wheels 866 fit into track 860 of each the first vertical beam 856 and second vertical beam 858. A ring 884 is attached to the top of each vertical member 864. The rings 884 surround rotating shaft 868 and allow rotating shaft 868 to rotate within rings 884. The base of actuator 870 is affixed to the nearest vertical member 864. The piston end of actuator 870 is rotatably attached to one end of member 886. The other end of member 886 is affixed to rotating shaft 868, so that when member 886 is moved, rotating shaft 868 moves. Thus, when piston extends from actuator 870, member 886 rotates and thereby rotates rotating shaft 868. [00164] Basket 102 comprises base 878, lip 880, and clamp 882. The user can roll a cart containing regulated medical waste and/or confidential documents onto base 878 of cart dumper 78. Lip 880 provides a lip around the top of basket 102 and is sized to both fit into the inner chamber 296 of feed hopper 14 and retain the cart (containing medical waste/documents) within basket 102 when raised and rotated so that the contents of the cart fall into the feed hopper 14 but not the cart. Clamp 882 allows basket 102 to be affixed to rotating shaft 868, so that when rotating shaft 868 rotates, so does basket 102.

[00165] The base of actuator 872 is affixed to horizontal beam 874. The end piston of actuator 872 is attached to ring 876. Ring 876 surrounds rotating shaft 868. The user can manipulate actuator 876 to extend and retract the piston and therefore raise or lower rotating shaft 868 of carriage 862. The guide wheels 856 of carriage 862 rotate within the tracks 860.

[00166] When the actuator 872 raises carriage 862, basket 102 (containing a cart full of regulated medical waste/documents) is raised as well. When the user has fully raised the carriage 862, the user can manipulate actuator 870, cause the piston to extend from actuator 870 and thus cause rotating shaft 868 to rotate and thereby cause basket 102 to rotate. The lip 880 extends into inner chamber 296 of feed hopper 14 and gravity pushes the contents of the cart into the feed hopper 14 while the lip 800 retains the cart. When the contents of the cart are emptied into the feed hopper 14, the user can manipulate actuator 870 to rotate basket 102 to its beginning upright position and, then, manipulate actuator 872 to lower basket 102 to its beginning position.

[00167] In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts as disclosed herein. Such modifications are to be considered as included in the following claims, unless those claims by their language expressly state otherwise.

Claims

CLAIMS What is claimed is:

1. An apparatus to process medical waste comprising:

a feed hopper adapted to receive waste material therein;

an integral shredder adapted to shred waste material received from the feed hopper;

a heated auger adapted to sterilize waste material received from the shredder; a discharge chamber comprising an inlet and an outlet adapted to receive sterilized waste material received from the heated auger;

a first retractable seal located between the feed hopper and the heated auger; a second retractable seal between the heated auger and the inlet of the discharge chamber; and

a third retractable seal between the outlet of the discharge chamber and an atmosphere external to the apparatus.

2. The apparatus of claim 1, wherein the first retractable seal includes a first door and a second door that form a seal when closed.

3. The apparatus of claim 1, wherein the first retractable seal includes a movable gate.

4. The apparatus of claim 3, wherein the feed hopper includes a door, the integral shredder includes a shredder assembly, an open bottom, and a screen between the shredder assembly and the open bottom, and the heated auger includes an inlet, a screw blade, an outlet, a chamber at least partially surrounding the screw blade, and a jacket at least partially surrounding the chamber.

5. The apparatus of claim 4, wherein the door of the feed hopper includes a front side, a flange fixedly attached to the front side of the door, a projection extending from the flange, and a lock rod comprising a lock end,

and wherein the feed hopper includes a switch positioned to contact the projection, when the door of the feed hopper is in a closed position, and a door well including a recess capable of receiving the lock end of the lock rod when the door is in a closed position.

6. The apparatus of claim 5, wherein the feed hopper includes an inner chamber, a first aperture, a second aperture, and a cooling coil,

wherein the first aperture provides a f uidic connection between the inner chamber and a vacuum blower; and

wherein the second aperture provides a fluidic connection between the inner chamber a source of steam.

7. The apparatus of claim 4, wherein the shredder assembly includes a set of cutter blades and the integral shredder includes a top surface, a pusher, and a cover fixedly attached to the first pusher and the top surface, and means to adjust the distance between the set of cutter blades and the screen.

8. The apparatus of claim 4, the jacket of the heated auger including an internal surface, an external surface, the external surface at least partially surrounding the internal surface, the volume between the internal surface and the external surface forming a jacket chamber, and the external surface including an aperture that is in fluidic communication with a source of steam to provide steam to the jacket chamber.

9. The apparatus of claim 8, the heated auger including a motor capable of moving the screw blade and a third aperture in fluidic communication with a source of steam.

10. The apparatus of claim 4, the discharge chamber including a fourth aperture in fluidic communication with the atmosphere external to the apparatus.

11. The apparatus of claim 4, the second retractable seal including butterfly valve.

12. The apparatus of claim 11, the third retractable seal including a butterfly valve.

13. The apparatus of claim 4, the second retractable seal including a sliding shield.

14. A method of treating medical waste comprising the steps of:

providing an apparatus comprising:

a feed hopper adapted to receive a waste material therein, and including a door and an inner chamber in fluid communication with a vacuum source and a steam source;

a heated auger adapted to sterilize waste material received from the shredder and including an outlet;

a discharge chamber comprising an inlet and an outlet adapted to receive sterilized waste material received from the heated auger; a first retractable seal between the feed hopper and the heated auger;

a second retractable seal between the heated auger and the inlet of the discharge chamber; and

a third retractable seal between the outlet of the discharge chamber and an atmosphere external to the apparatus; opening the door of the feed hopper;

ensuring that the first retractable seal is closed, the second retractable seal is opened, and the third retractable seal is closed;

drawing air from the atmosphere into the inner chamber via the vacuum source;

placing a first batch of medical waste into the inner chamber of the feed hopper;

closing the door of the feed hopper;

reducing the pressure within the apparatus between the feed hopper and the first retractable seal to a first negative pressure;

increasing the temperature and pressure within the apparatus between the feed hopper and the first retractable seal to a second temperature and pressure and increasing the temperature and pressure within the apparatus between the first retractable seal and the third retractable seal to a third temperature and pressure; opening the first retractable seal;

shredding a first batch of medical waste; allowing a first batch of medical waste to proceed to the heated auger;

closing the first retractable seal;

reducing the temperature within the apparatus between the feed hopper and the first retractable seal and the pressure to approximately atmospheric pressure, to allow the placement of a second batch of medical waste into the feed hopper, if desired, while a first batch of medical waste is still within the heated auger;

advancing a first batch of medical waste through the outlet of the heated auger and through the inlet of the discharge chamber;

closing the second retractable seal;

reducing the pressure within the discharge chamber to approximately a pressure of an atmosphere external to the apparatus;

opening the third retractable seal; and

removing a first batch of medical waste from the apparatus.

15. The method of claim 15, the second temperature and pressure being approximately equal to the third temperature and pressure, and being about 248°F and 14.8 psig, and the first negative pressure being less than or equal to about negative 5 psig.

16. The method of claim 15, the heated auger including a screw blade and a chamber at least partially surrounding the screw blade, wherein the step of advancing a first batch of medical waste through the outlet of the heated auger and through the inlet of the discharge chamber is achieved via the rotation of the screw blade.

17. The method of claim 16, the heated auger of the apparatus including a jacket at least partially surrounding the chamber, and

including the step of increasing the temperature between the jacket and the chamber of the heated auger to approximately 248 degrees Fahrenheit.

18. The method of claim 17, wherein step of placing a first batch of medical waste into the inner chamber of the feed hopper is achieved using a cart dumper.

19. A method of treating medical waste comprising the steps of:

providing an apparatus comprising: a feed hopper adapted to receive a waste material therein, and including a door and an inner chamber in fluid communication with a vacuum source and a steam source;

a heated auger adapted to sterilize waste material received from the shredder, and including an outlet;

a second retractable seal between the heated auger the inlet of the discharge chamber; and

a third retractable seal between the outlet of the discharge chamber and an atmosphere external to the apparatus;

opening the door of the feed hopper;

drawing air from the atmosphere into the inner chamber via the vacuum source;

closing the door of the feed hopper;

shredding a first batch of medical waste;

allowing a first batch of medical waste to proceed to the heated auger;

closing the first retractable seal; reducing the temperature within the apparatus between the feed hopper and the first retractable seal and the pressure to approximately atmospheric pressure; opening the door of the feed hopper;

drawing air from the atmosphere into the inner chamber via the vacuum source;

placing a second batch of medical waste into the feed hopper;

closing the door of the feed hopper;

reducing the pressure within the apparatus between the feed hopper and the first retractable seal to less than or equal to the first negative pressure;

increasing the temperature and pressure within the apparatus between the feed hopper and the first retractable seal to approximately the second temperature and pressure and increasing the temperature and pressure within the apparatus between the first retractable seal and the third retractable seal to approximately the third temperature and pressure;

opening the first retractable seal;

advancing a first batch of medical waste closer to the outlet of the heated auger

shredding a second batch of medical waste;

allowing a second batch of medical waste to proceed to the heated auger; closing the first retractable seal; and

reducing the temperature within the apparatus between the feed hopper and the first retractable seal and the pressure to approximately atmospheric pressure, to allow the placement of a third batch of medical waste into the feed hopper, if desired, while a first batch of medical waste and a second batch of medical waste are still within the heated auger.

20. The method of claim 19, the second temperature and pressure being approximately equal to the third temperature and pressure, and being about 248°F and 14.8 psig, and the first negative pressure being less than or equal to about negative 5 psig and further including the steps of: advancing a first batch of medical waste through the outlet of the heated auger and through the inlet of the discharge chamber;

closing the second retractable seal;

reducing the pressure within discharge chamber to approximately the pressure of the atmosphere external to the apparatus;

opening the third retractable seal; and

removing a first batch of medical waste from the apparatus.