WO1999035916A2

WO1999035916A2 - An anti-microbial treatment system for and method of disinfecting animal carcasses

Info

Publication number: WO1999035916A2
Application number: PCT/US1999/001108
Authority: WO
Inventors: Kevin M. Mowery; Steven J. Mueller; Philip H. Allen; Robert L. Hormell; Robert J. Killian; Khalid M. Aly; Walter C. Maag; Joseph J. Farina
Original assignee: Novus International, Inc.
Priority date: 1998-01-20
Filing date: 1999-01-19
Publication date: 1999-07-22
Also published as: WO1999035916A3; AU2327299A

Abstract

This disclosure relates to an anti-microbial treatment system for disinfecting animal carcasses. The system includes a system for mixing two components of an anti-microbial liquid chemical and delivering a homogeneous mixture of such chemical to an application system for applying the chemical to animal carcasses to disinfect them. One such application system disclosed is a spray cabinet system comprising one or more spray cabinets (171), each of which is equipped with low-volume spray nozzles for spraying liquid chemical on carcasses (C) transported through the cabinet. The entire system operates under the control of a programmable logic controller for controlling and monitoring the system and for recording and reporting data regarding the status of the system and components thereof.

Description

AN ANTI-MICROBIAL TREATMENT SYSTEM FOR AND METHOD OF DISINFECTING ANIMAL CARCASSES

Background of the Invention

This invention relates generally a system for treating food with an anti-microbial liquid chemical to sanitize and disinfect the food and, more particularly, to a system (apparatus and method) for mixing and delivering such a liquid chemical to an applicator such as a spray cabinet for spraying the liquid chemical on animal carcasses.

This invention has particular application to fresh meat products, including but not limited to poultry, which are susceptible to contamination by microorganisms immediately after the animal has been slaughtered and eviscerated. USDA and FDA regulations require that steps be taken to eliminate or at least minimize this contamination. These steps typically include washing the animal carcasses with water and a disinfecting agent, such as chlorine, and then dipping them in one or more chill tanks containing a disinfectant solution. More recently, it has been discovered that applying an aqueous solution of acid and metal chlorite to the carcasses prior to the chilling stage of the process is particularly effective. This methodology is described in detail in several patents owned by Alcide Corporation, including U.S. Patent No. 5,389,390, incorporated herein by reference.

The aforementioned patent discloses that acid and metal chlorite solutions can be mixed together to form a disinfectant solution which is directed into and through a spray head which mixes appropriate volumes of each liquid to produce an effluent spray containing the appropriate ingredients. Alternately, the patent discloses that the two solutions can be premixed in a reservoir, stored for a limited period of time and thereafter a single liquid stream can be directed through a sprayer. However, the patent does not disclose a specific commercially viable system for mixing the components to form a disinfectant solution, and for then delivering this solution to a mechanism for applying it to animal carcasses. Furthermore, while the patent discloses the general concept of spraying disinfectant solution on animal carcasses, there is no specific disclosure of how an effective spray system should be designed or how it could be incorporated in a high-volume production line of a processing plant.

Summary of the Invention

Among the several objects of this invention may be noted the provision of a system for and method of mixing and delivering a multi-component anti-microbial liquid chemical to a system for applying the liquid chemical to animal carcasses; the provision of such a mixing and delivery system and method which deliver a homogeneous mix of chemical solution to the applicator system at a uniform rate; the provision of such a mixing and delivery system and method which utilize standard pieces of equipment to minimize costs; the provision of such a mixing and delivery system which is easy to operate and maintain; the provision of an improved applicator system which includes one or more spray cabinets capable of applying a desired amount of disinfectant solution to animal carcasses over a desired period of time, thereby maximizing the effectiveness of the solution to kill bacteria on the surfaces of the carcasses; the provision of such a spray cabinet which sprays solution at very low volumes to reduce cost; the provision of such a spray cabinet which is effective for contacting all exterior surfaces of the carcasses; the provision of such a spray cabinet which effectively contains spray within the cabinet and inhibits the escape of spray from the cabinet; the provision of such a spray cabinet in which air and contaminated liquid exit the cabinet at two separate locations to facilitate disposal; the provision of such a spray cabinet which is modular in form so that multiple cabinets can be joined end to end and/or side by side for greater flexibility in matching existing production line speeds and/or configurations; the provision of such a spray cabinet which is easy to clean and maintain; the provision of such a cabinet which is simple in construction for efficient production; the provision of such a spray cabinet that installs directly onto and may be suspended from the overhead rail system of an animal slaughtering facility; and the provision of an improved method of applying anti-microbial liquid chemical to animal carcasses to disinfect them as they are transported through spray cabinets of the type mentioned above.

Among the additional objects of this invention may be noted the provision of a system for controlling and monitoring a carcass processing line and for recording and reporting data corresponding to various conditions and/or parameters of the carcass processing line; the provision of such a system including a controlled treatment station at which the carcasses are treated such as by washing and/or by chilling with a treatment liquid; the provision of such a system for monitoring a condition (or parameter) of the treatment liquid used at the treatment station or of the line itself; the provision of such a system for indicating an alarm when the treatment is outside an acceptable range; and the provision of such a system includes various control loops to maintain water flow and other system parameters within acceptable limits. In general, the present invention involves a system for mixing and delivering an anti-microbial liquid chemical to an application system for applying the liquid chemical to animal carcasses. The mixing and delivery system comprises a first tank for holding a first component of said liquid chemical in concentrated form, a second tank for holding a second component of said liquid chemical in concentrated form, and a water supply system. The system also includes a first pump for pumping said first component from the first tank to the water supply system to provide a diluted first component, and a second pump for pumping said second component from the second tank to the water supply system to provide a diluted second component. The system further comprises at least one static mixer having an inlet for receiving said diluted first and second components, and an outlet. The mixer is operable to thoroughly mix the diluted first and second components to provide a substantially homogeneous mixture of anti-microbial liquid chemical. A chemical delivery line delivers the homogeneous mixture from the outlet of the mixer to the aforesaid application system.

The present invention also involves a method of mixing and delivering an anti-microbial liquid chemical to an application system for applying_, the liquid chemical to animal carcasses. The method comprises holding in a first tank a first component of said liquid chemical in concentrated form, holding in a second tank a second component of said liquid chemical in concentrated form, pumping the first component from the first tank and diluting it to provide a diluted first component, and pumping the second component from the second tank and diluting it to provide a diluted second component. The diluted first and second components are delivered to the inlet of a static mixer. The method further comprises mixing the diluted first and second diluted components in the static mixer to provide a substantially homogeneous mixture of said anti-microbial liquid chemical, and delivering the homogeneous mixture from an outlet of the mixer to the aforesaid application system for applying the mixture to said animal carcasses.

Another aspect of this invention is directed to a spray cabinet system for spraying animal carcasses with an anti-microbial liquid chemical. This spray cabinet system comprises a cabinet having opposite sides, a top and a bottom defining a spray chamber, an entryway at an entry end of the cabinet for entry of animal carcasses into the spray chamber, and an exitway at an exit end of the cabinet for exit of animal carcasses from the spray chamber. A spray system is provided inside the spray chamber for spraying liquid chemical onto animal carcasses as they are transported through the cabinet. The entryway and exitway are sized not substantially larger than necessary to accommodate said animal carcasses so as to inhibit the escape of spray from the spray chamber. A drain is provided in the bottom of the cabinet for draining liquid from the cabinet. An exhaust system is connected to the top of the cabinet and communicates with the spray chamber for drawing air out of the spray chamber and reducing the pressure in the spray chamber thereby further inhibiting the escape of spray from the spray chamber via said entryway and exitway.

In another aspect of this invention, the spray cabinet system comprises a cabinet having opposite sides, a top and a bottom defining a spray chamber, an entryway at an entry end of the cabinet for entry of animal carcasses into the spray chamber, and an exitway at an exit end of the cabinet for exit of animal carcasses from the spray chamber. The spray cabinet also includes a spray system inside the spray chamber for spraying liquid chemical onto animal carcasses as they are transported through the cabinet. The spray system comprises a plurality of low-volume spray nozzles, each configured for spraying said liquid chemical at a rate of about 0.05-0.3 gpm, said spray nozzles being located to generate a chemical fog throughout the spray chamber for continuously exposing each animal carcass to said liquid chemical as it is transported from the entry opening to the exit opening. Another aspect of this invention involves a method of applying an anti-microbial liquid chemical to animal carcasses. The method comprises providing a spray cabinet having an enclosed spray chamber and a plurality of spray nozzles oriented for spraying said liquid chemical into the spray chamber, spraying liquid chemical through the spray nozzles at a rate of about 0.05-0.3 gpm per nozzle to generate a chemical fog throughout the spray chamber, and transporting animal carcasses through the spray chamber while said chemical fog is being generated thereby to continuously expose each animal carcass to the liquid chemical as it is transported through the spray chamber.

Still another aspect of this invention involves a modular spray cabinet system for spraying an anti- microbial liquid chemical on animal carcasses. The system comprises a plurality of cabinet modules. Each cabinet module comprises a frame and a plurality of panels mounted on the frame defining a spray chamber for passage of animal carcasses therethrough. The cabinet module has an entry end configured for entry of animal carcasses into the spray chamber and an exit end configured for exit of carcasses from the spray chamber. An annular connector is provided for sealingly connecting first and second cabinet modules end to end. The connector has a first end face sealingly engageable with the exit end of the first cabinet module and a second end face sealingly engageable with the entry end of the second cabinet module whereby animal carcasses exiting the first cabinet module pass through the connector before entering the second cabinet module.

Still another aspect of this invention involves a system for treating animal carcasses being transported along a processing line. A sensor positioned along the processing line monitors the movement of animal carcasses being transported along the processing line and generates a carcass movement signal representative thereof. An applicator applies an anti-microbial liquid chemical to each of the animal carcasses as they are transported along the processing line. A controller receiving the carcass movement signal controls the applicator in response to the carcass movement signal to thereby apply the anti-microbial liquid chemical to each of the transported animal carcasses as a function of the animal carcass movement signal generated by the sensor. The invention further comprises a system for treating animal carcasses being transported along a processing line including a treatment station at which the birds are treated such as by washing or chilling. An applicator applies an anti-microbial liquid chemical to each of the animal carcasses as they are transported along the processing line. A controller controls the applicator to apply the anti-microbial liquid chemical to each of the transported animal carcasses. A treatment sensor monitors a condition of a treatment liquid used at the treatment station. The treatment sensor provides a treatment signal to the controller indicating the condition of the treatment liquid. An alarm is activated by the controller when the treatment signal indicates that the condition of the treatment liquid is outside an acceptable range. The invention also encompasses a method for treating animal carcasses being transported along a processing line comprising the steps of: monitoring the movement of animal carcasses being transported along the processing line; applying an anti-microbial liquid chemical to each of the animal carcasses as they are transported along the processing line; and controlling the amount of the anti-microbial liquid chemical applied during the applying step in response to the monitoring step to thereby apply the anti-microbial liquid chemical to each of the transported animal carcasses as a function of the monitored animal carcass movement . Other objects and features will be in part apparent and in part pointed out hereinafter.

Brief Description of the Drawings

Figs. 1A-1C are schematic views of a mixing and delivery system of the present invention; Fig. 2 is a view of a building for housing various components of the system of Fig. 1;

Fig. 3 is a view showing an arrangement for mounting various mechanical components (in phantom) of the system inside the building of Fig. 2; Fig. 4 is a side elevation of a spray cabinet of the present invention suspended from an overhead rail conveyor;

Fig. 5 is an end elevation of the cabinet of Fig. 4;

Fig. 6 is an exploded perspective view of a frame assembly of the spray cabinet;

Fig. 7 is a partial perspective of an end of the spray cabinet with parts broken away to show details;

Fig. 8 is a vertical section taken on line 8--8 of Fig. 4 ; Fig. 9 is an enlarged vertical section taken on line 9--9 of Fig. 4;

Fig. 10 is an enlarged fragmentary view showing a hinge connection between the frame and a bottom panel of the spray cabinet;

Fig. 11 is a schematic view showing a spray configuration of the present invention;

Fig. 12 is a side elevation illustrating two cabinet modules connected end to end; Fig. 13 is a view showing a connector for connecting two cabinet modules end to end;

Fig. 14 is a view showing two pairs of cabinet modules connected side-by-side;

Figure 15 is a schematic diagram mostly in block form of one preferred embodiment of a system architecture according to the invention for controlling, monitoring, recording and reporting data relating to a chicken carcass processing line.

Figure 16 is a simplified flow diagram illustrating operation of the system of Figures 1A-1C with respect to monitoring of chlorine dioxide levels, pH levels, pressure ranges, temperature ranges and flow loops and ranges .

Figure 17 is a diagram illustrating the process control definition for the system of Figures lA-lC.

Figures 18A and 18B are logic diagrams illustrating a start-up sequence for programming a programmable logic controller (PLC) used as a control of the system of Figures lA-lC. Figure 19 is a logic diagram illustrating a sequence when all lines are idle for programming a programmable logic controller (PLC) used as a control of the system of Figures 1A-1C.

Figure 20 is a logic diagram illustrating a sequence when line one (#1) is idle for programming a programmable logic controller (PLC) used as a control of the system of Figures 1A-1C.

Figure 21 is a logic diagram illustrating a shutdown sequence for all conveyor lines for programming a programmable logic controller (PLC) used as a control of the system of Figures lA-lC.

Figure 22 is a logic diagram illustrating a shutdown sequence for conveyor line one (#1) for programming a programmable logic controller (PLC) used as a control of the system of Figures 1A-1C.

Corresponding parts are designated by corresponding reference numerals throughout the several views of the drawings .

Detailed Description of the Preferred Embodiment Referring now to the drawings, and first to Figs. 1A-1C, a system for mixing and delivering an antimicrobial liquid chemical to an applicator system for applying the chemical to animal carcasses is indicated in its entirety by the reference numeral 1. The mixing and delivery system is particularly adapted for handling a multi-component liquid chemical, preferably but not necessarily of the type described in the aforementioned U.S. Patent No. 5,389,390 owned by Alcide Corporation, where one of the components is a metal chlorite and the other a generally recommended as safe (GRAS) acid (e.g., citric acid) . When mixed, these components form an acidified metal chlorite solution which is applied to animal carcasses to kill bacteria residing on the surfaces of the carcasses. A suitable application system of the invention is generally designated by the reference numeral 3 in Fig. IC. As illustrated, this system 3 is a spray cabinet system for spraying solution on the carcasses as they pass through the system, as will be described later in this disclosure. As shown in Fig. 1A, the mixing and delivery system comprises a first tank 7 for holding a first component (e.g., a suitable acid solution) of the liquid chemical in concentrated form. This tank may be an insulated and, if necessary heated, storage tank having an inlet line 9 with a quick-connect fitting 11 for rapid connection to a suitable source 13 (e.g., a tank truck) to allow filling of the tank, and an outlet line 17 for exit of the liquid from the tank. Flow through the inlet line 9 is preferably controlled by an automated valve 19 (e.g., Plast-O-Matic model No. MBV200-VS-CP with EBV-104 activator) under operator control or responsive to a controller (such as PLC 702 noted below) . Liquid is drawn from the tank via the tank outlet line 17 by means of a first metering pump 21 having an intake connected to the outlet line 17 of the tank, and a discharge. The pump may be, for example, a Milton Roy Mroy L diaphragm pump model No. RA12-1015SR having a variable speed drive 25 under the control of an electronic controller 27 connected to a suitable programmable logic controller (see PLC 702 in Fig. 15) which controls the overall system. The discharge rate of the pump 21 is set according to various factors which will be described below. A calibration device 31 is provided immediately upstream from the metering pump 21 for calibration purposes. If necessary, flow from the tank can be shut off by means of a solenoid-operated valve 33 in the tank outlet line 17 upstream from the pump.

The mixing and delivery system also includes a second tank 41 similar to the first for holding a second component (e.g., a suitable metal chlorite solution) of the liquid chemical in concentrated form. Like the first tank 7, the second tank 41 has an inlet line 43 with a quick-connect fitting 45 for connection to a suitable source 49 (e.g., a tank truck) to allow filling of the tank, and an outlet line 51 for exit of liquid from the tank. Flow through the inlet line 43 is preferably controlled by an automated valve 53 similar to valve 19. Solution is drawn from the tank 41 by means of a second metering pump 57 having an intake connected to the outlet line 51 of the second tank, and a discharge. The pump 57 may be the same as the first pump 21 described above, having a variable speed drive 59 under the control of an electronic controller 61 connected to the PLC. A calibration device 63 is provided immediately upstream from the pump 57 for calibration purposes. If necessary, flow from the tank 41 can be shut off by means of a solenoid-operated valve 67 in the tank outlet line 51 upstream from the pump. Each of the first and second tanks 7, 41 is equipped with a suitable level indicator 71 for visually indicating the level of liquid in the tank, and a level transmitter 73 for transmitting a signal to a remote location indicating the level of liquid in the tank. The level transmitter 73 enables the tank to more conveniently and more efficiently refilled, as described in more detail in co-assigned, co-pending U.S. application Serial No. 08/636,289, filed April 23, 1996 for INTEGRATED SYSTEM MONITORING USE OF MATERIALS, CONTROLLING AND MONITORING DELIVERY OF MATERIALS AND PROVIDING AUTOMATED BILLING OF DELIVERED MATERIALS, incorporated herein by reference. In addition, the level transmitter 73 provides tank level information to the system controller (PLC 702) so that the tanks are not overfilled and are protected from excessive pressure while being filled from the trucks. When one of the tank transmitters 73 indicates that its tank is full, the controller closes its valve 19, 53 to prevent further filling. The temperature of liquid flowing through each of the tank outlet lines 17, 51 to a respective pump 21, 57 is monitored by a temperature monitoring device 75 capable of transmitting a temperature-indicating signal to the PLC. A suitable device is SSI model No. EHA-NUN- 6-SSDO equipped with transmitter Wilkinson model No. SC5010.

The mixing and delivery system 1 of the present invention further comprises a water supply system, generally designated 81, and one or more in-line static mixers 83 (only one is shown in Fig. IB) having an inlet 85 connected to the water supply system. The water supply system includes a potable water supply 87 and a main water line 89 connecting the water supply and the static mixer (s) 83. Water is delivered from the water supply to the mixer by means of a pump 91, which may be a multi-stage centrifugal pump. A suitable water filter system comprising a pair of water filters 93 is provided in the main water line upstream from the pump 91, as indicated in Fig. 1A. The flow of water through these two water filters 93 is controlled by three-way valves, each indicated at 97. A pressure monitoring device 101 is provided for sensing the pressure of the water in the main water line 89 immediately upstream from the pump 91, and for transmitting a pressure signal corresponding to the pressure to the aforementioned PLC. (A low pressure indicates a dirty or plugged water filter 93) . The flow rate through the main water line 91 downstream from the pump 91 is monitored by means of a magnetic flow meter 103 capable of transmitting a flow signal to the PLC. The pressure in the water line downstream from the pump is controlled by a pressure regulator indicated at 107. Pressure gages 109, 111 connected to the water line upstream and downstream from the pressure regulator 107 provide a visual pressure reading. A pair of mixing filters are installed in the main water line 81 downstream from the water pump 91 and pressure regulator 107 and upstream from the static mixer 83, the first of these mixing filters being designated 115 and the second 119 (Fig. IB.) An acid supply line 121 connects the discharge of the first pump 21 with an inlet port 123 of the first filter 115 for delivery of acid solution to this filter. Similarly, a metal chlorite supply line 127 connects the discharge of the second pump 57 with an inlet port 129 of the second filter 119 downstream from the first filter 115 for delivery of metal chlorite solution to the second filter. The two filters function to at least roughly mix respective concentrated solutions with water in the main water line 89 to provide diluted solutions which are then delivered to the static mixer (s) 83. The two filters 115, 119 may be of any suitable type so long as they are capable of performing this function. Filters commercially available from Pall (filter housing model No. SCY1RFG16H13; filter model No. PFY1UY100J) have been found to be suitable for this purpose. Each of these filters preferably has a sample line 131 with a sampling valve 133 connected thereto for sampling solution from the filter. Flow through the acid and metal chlorite supply lines 121, 127 is monitored by flow meters 141 (Fig. IB) capable of sending signals to the PLC indicative of the flow rates through respective lines. A flow switch 145 is also provided downstream from each flow monitor 141 for monitoring the flow through either line.

As shown in Fig. IB, the static mixer 83 installed in the main water line 89 and located downstream from the two filters 115, 199 receives the diluted acid and metal chlorite solutions and thoroughly mixes them to provide a substantially homogeneous mixture of anti-microbial liquid chemical to be delivered to the spray cabinet system 3. For the most efficient results, it is important that this mixture be substantially homogeneous. A static in-line mixer of the type sold by TAH, Model No. 050-122 has been found to provide satisfactory results without the need for a downstream surge tank or the like. As previously noted, the acid and metal chlorite pumps 21, 57 are preferably standard diaphragm pumps. (These pumps could also be gear pumps, piston pumps, or other types.) As will be understood by those skilled in this field, diaphragm pumps typically deliver a pulsing flow of liquid. To ensure a more homogeneous mixture, it is desirable that solution be supplied to the static mixer 83 at a uniform and consistent rate, and not in a pulsing or intermittent manner. Accordingly, when using diaphragm pumps, pulse dampeners 151 are provided in the acid and metal chlorite supply lines 121, 127 downstream from the pumps 21, 57. The dampener 151 in the acid line may be Blacoh model No. CTPIOOOV, and the dampener in the metal chlorite line may be a Blacoh model No. CTK1000V. Spring-loaded back pressure valves 155 are provided downstream from the dampeners in respective supply lines 121, 127. These valves are set to close at predetermined pressures to protect the upstream system components against downstream pressure pulses.

Optionally, a second in-line static mixer can be placed in the main water line 89 between the two filters 115, 119. Alternatively, the two filters 115, 119 can be replaced with a second static mixer in line 89 at a location in the line between the acid and metal chlorite supply lines 121, 127.

Thoroughly mixed anti-microbial liquid chemical is delivered from the outlet 161 of the static mixer 83 to the spray cabinet system 3 by means of a main chemical delivery line 163 having a series of branch delivery lines 165A-165D, one for each spray cabinet 171 of the system. (Four such spray cabinets are shown in Fig. IC.) A pH measuring unit 175 (Fig. IB) comprising a probe, pH meter and transmitter is installed in a branch line 179 off the main delivery line 163 for measuring the pH of the solution delivered from the mixer 83 and transmitting this measurement to a remote location and/or the PLC. The unit 175 may include, for example, GLI probe model No. 6058POLCP, and transmitter model No. P63A1N1A1A1N. A relief valve 181 or back pressure device is provided in a line 183 off the main chemical delivery line 163 immediately downstream from the static mixer 83. A sampling line 187 and associated valve 189 are provided off the main delivery line 163 downstream from the pH unit 175 for sampling solution taken from the delivery line.

Flow through each of the branch delivery lines 165A- 165D is controlled by a solenoid operated shut-off valve 201 and a control valve downstream 203 from the shut-off valve (Fig. IC.) A suitable flow monitor 207 is provided immediately upstream from the control valve 203 for sensing the flow rate through the respective line 165A- 165D and transmitting a flow signal to the PLC. The flow monitor 207 may be, for example, a Endress & Hauser model No. 30A-T-15AD1ED11D11D11B device. The flow position of the control valve 203 is set by the PLC via a valve controller 208 to deliver chemical solution to its associated spray cabinet 171 at a predetermined rate. A pressure monitor 209 (and associated pressure gage 211) is provided downstream from the control valve for monitoring pressure in the line and transmitting a suitable pressure signal to the PLC. An additional pressure gage 213 is provided in the branch delivery line immediately adjacent to each spray cabinet. It is important that the main chemical delivery line 163 and associated branch lines 165A-165D be free of any substantial interruptions which would tend to interrupt the uniform flow of homogeneous chemical mixture from the static mixer 83 to the spray cabinets 171. This will ensure that the chemical sprayed on the animal carcasses is most effective in killing bacteria on the carcasses. The system 1 of the present invention is equipped for flushing the chemical delivery line 163, associated branch lines 165A-165D and spray cabinets 171 with a suitable cleaning solution. This capability is provided by a main flush line 215 connected to the main water line 89 upstream of the filters 115, 119 and a series of branch flush lines 217A-217D connected to respective branch chemical delivery lines 165A-165D downstream from the shut-off valve 201 and upstream from the control valve 203. A manually operated valve 221 (Fig. 1A) is installed in the main flush line, and a solenoid-operated shut-off valve 225 is installed in each branch flush line 217A-217D. Thus, by closing the shut-off valves 201 in one or more branch delivery lines 165A-165D and opening the manual valve 221 and shut-off valves 225 in the main flush line 215 and appropriate branch flush lines 217A- 217D, respectively, water can be diverted from the main water line 89 to any one or more of the branch delivery lines 165A-165D for flushing the line(s) and the downstream spray cabinet (s) 171 and associated components. A pressure regulator 227 is installed in the flush line 215 to regulate flush water pressure. Suitable flow control shutoff valves 231, check valves 235 and strainers 237 are installed at appropriate locations in the mixing and delivery system described above, as will be understood by those skilled in this field. The various components of the system shown within the dashed lines 241 in Figs. 1A-1C are preferably housed within an enclosed building 243 (Fig. 2) having suitable heating and/or cooling systems (not shown) for controlling the air temperature inside the building. In this manner the temperature of the water and chemical solutions can be maintained within desired limits as they are pumped from their respective sources and mixed for delivery to the spray cabinets 171. Water and solution lines leading to and from the enclosure are insulated and/or heated, as needed. The building also has doors 245 which can be locked to provide additional security for the system.

As illustrated in Figs. IB and 3, the mechanical components of the mixing and delivery system 1 are mounted above a series of drip pans on the floor inside the building 243. These pans preferably include a drip pan 301 below the water line components of the system and separate drip pans 303, 305 below the mechanical components for pumping the two liquid chemicals. (It may be desirable to keep any water and chemicals dripping or leaking from the pumps, etc. separate from one another to the extent possible to avoid the formation of undesirable gases.) Level sensors 307 are installed in the pans 301, 303, 305 for detecting the level of liquid in the pans and providing an alarm signal if the liquid rises above a predetermined level.

A venting system is used for removing gases emanating from liquids in the drip pans 301, 303, 305. The system comprises a horizontal vent line 311 (Fig. IB) running above the pans and having a series of spaced intake opening therealong, and a fan 315 drawing gases into the vent line 311 and discharging them to atmosphere. For safety reasons, one or more monitors 321 (Fig. 1A) are installed inside the building 243 at locations above the vent line 311 for sensing the presence of toxic gas (e.g., chlorine dioxide) in the building. A display 323 associated with each monitor 321 is mounted on the outside of the building for alerting persons to the presence of any such gas before they enter the building (see Fig. 2.) The monitor may also be connected to an alarm for alerting persons in the area and/or to a transmitter capable of sending information concerning the environment inside the building to a remote location.

The building 243 contains suitable enclosures for housing various electronic components of the system, such as the PLC of the system.

For ease of fabrication and maintenance, the mechanical components of the mixing and delivery system 1 can be mounted by means of hangers, shelves and the like on a single frame 331 removably secured to the floor of the building 243 above the drip pans 301, 303, 305, as shown in Fig. 3. Also, the building itself can be mounted on beams 333 or other structure so that it can be moved readily by forklift or other vehicles from one location to another. The distance between the building 243 and the spray cabinets 171 may vary from several feet to several thousand feet. However, as noted above, the lines 163, 165A-165D delivering the mixed chemicals to the spray cabinets 171 should be free of any substantial interruptions which would tend to interrupt the uniform flow of homogeneous mixture to the spray cabinets .

As best illustrated in Figs. 4-6, each spray cabinet 171 comprises a frame assembly, generally designated 401, a series of panels mounted on the frame assembly forming opposite sides 403, a top 405 and a bottom 407 which combine to define a spray chamber 411 inside the cabinet, an entryway 415 at the entry end of the cabinet and an exitway 419 at the exit end of the cabinet. The cabinet is formed from a material which can be sterilized, such as stainless steel.

Specifically, the frame assembly 401 comprises an upper frame, generally designated 421, engageable with an overhead rail conveyor 425 system typically found in animal processing plants, and a lower frame, generally designated 427, removably attached to the upper frame 421 and supporting the panels defining the spray chamber 411 at a location spaced below the rail conveyor 425. It will be understood by those skilled in this industry that the aforementioned rail conveyor system conveys animal carcasses C held on shackles S along a processing line so that various processing steps (e.g., washing, disinfecting, chilling, etc.) can be carried out on the carcasses at high speed for high-volume production. The spray cabinet 171 of the present invention is designed so that it can be readily installed in a typical production line of this type. Of course, the cabinet may also be used in other environments. It is further contemplated that the spray cabinet 171 could be suspended from other structures in a plant, or that it could be a freestanding cabinet not mounted on any structure.

As shown in Figs. 6 and 7, the upper frame 421 has a rectangular top 431 and four legs 433 extending down from the corners of the top. The frame is preferably fabricated from tubular metal bar stock as a single weldment, except for a side part comprising one top side frame member 435 and two legs secured thereto which are removable to facilitate installation of the upper frame on the conveyor system (or other structure) as shown in Figs. 4 and 5. The side frame member 435 and two legs 433 associated therewith are removably attached to the frame by suitable connecting pieces 437 and fasteners 441. Alternatively, the removable side part could be simply the two legs 433 at one side of the upper frame. The lower frame 427 which supports the panels of the cabinet has a rectangular bottom framework 447 and four legs 449 extending up from the corners of the framework. These frame members 447, 449 are also preferably formed from tubular metal bar stock and fabricated as a single weldment. The legs 433, 449 of the upper and lower frames have a telescoping fit and are secured together by fasteners 451 inserted through mating holes 453 in the legs. Each of the legs 449 on the lower frame 427 has a series of vertically spaced holes 453 therein so that the elevation of the spray chamber 411 can be adjusted as needed. Alternatively, the adjustment holes can be in the legs of the upper frame. The lower frame 427 has a top framework 457 spaced above the bottom framework 447 for supporting the top 405 of the cabinet. The top framework 457 comprises a pair of spaced apart parallel guide rails 461 which define a slot 463 running the entire length of the lower frame to allow passage of shackles S carried by the overhead rail conveyor 425 through the cabinet from one end to the other. The guide rails 461 extend beyond the entry end of the lower frame 427 and diverge outwardly to form a funnel for guiding shackles and carcasses carried thereby into the slot 463 defined by the guide rails 461, as will be described. The diverging ends of the guide rails are reinforced and protected by loops 467 at their outer ends. The guide rails 461 also extend a short distance beyond the exit end of the frame.

The lower frame 427 defines a pair of side openings 471 at opposite sides of the frame. A channel 473 is secured to the frame around the periphery of each of these openings 471. As shown best in Fig. 9, this channel has, in transverse cross section, a pair of generally parallel legs 475 connected by a web 477 which seats against a side of the frame 427 so that one leg 475 is on the outside of the frame (the underside as shown in Fig. 9) and the second leg 475 is spaced from the frame in the frame opening 471. The second leg terminates in a knife edge 481 which extends around the entire perimeter of the frame opening 471.

Each of the two sides 403 of the cabinet comprises a single panel 485 formed of sheet metal bent to have a shallow peripheral rim 487 (Fig. 9) . These panels 485 are mounted on the lower frame 427 by quick-operating fasteners, each generally designated 489, so that the panels can be rapidly removed to provide immediate access to the inside of the cabinet for cleaning and maintenance purposes and then rapidly reinstalled. The fasteners may be quick-release latches, for example, each having a rotatable handle 491 on the outside of the panel and a camming latch 493 on the inside of the panel engageable with the lower frame 427 when the handle is turned in one direction to cam (pull) the panel tight against the lower frame, and disengageable from the lower frame when the handle is turned in an opposite direction to permit removal of the panel. Other types of quick-operating fasteners may be used. A rectangular gasket 497 is provided around the periphery of each side panel 485 on the inside of the panel. The gasket is disposed between a gasket retainer 501 secured to the panel and the peripheral rim of the panel 487 (Fig. 9.) The gasket 497 is preferably glued or cemented in place. When the latches 489 are turned to latch the panel closed, the gasket 497 seats against the knife edge 481 on the frame to provide a liquid and air-tight seal.

The bottom 407 of the spray chamber 411 comprises a panel 505 of sheet metal bent to have an upstanding rim 507 (Fig. 5) which extends up above the bottom of the frame on the outside of the bottom lower framework 447 to prevent leakage. The bottom surface of the panel 505 has side portions which slope down toward one or more drain holes 513 at the center of the panel connected via a line 515 to a drainage system 519 (Fig. IC.) The bottom panel 505 is hingedly connected to opposite sides of the bottom framework 447 so that the panel may be swung down from a closed position to an open position from either side of the frame or removed entirely to facilitate cleaning of the cabinet. Each hinge connection (four total, one adjacent to "each corner of the bottom of the frame) comprises a lug 525 secured, as by welding, to the lower frame 427, an L-shaped bracket 527 secured to the bottom panel 505 adjacent a respective corner thereof, and a pin 531 removably inserted through aligned holes in the bracket and lug (see Fig. 10.) The bottom panel has handles 535 at opposite sides thereof to facilitate opening and closing the panel .

The lower frame 427 also defines a pair of end openings 541 at opposite ends of the frame (Fig. 6.) The entryway 415 and exitway 419 are mounted in these openings and extend outwardly therefrom at opposite ends of the cabinet 171. As shown best in Figs. 4 and 7, the entryway and exitway each comprises first (inner) and second (outer) upright baffle plates designated 545 and 547, respectively, and a rectangular cabinet extension 549 which mounts the baffle plates in spaced apart relation to define the aforementioned entryway/exitway. These components may also be fabricated from sheet metal . The cabinet extension 549 has lips 551 along its lower and side edges which extend into a respective end opening 541 of the lower frame, the lip 551 at the lower edge of the extension being somewhat longer to ensure proper drainage of liquid back into the spray chamber 411. The cabinet extension 549 is secured to the lower frame 427 by suitable fasteners. The bottom of the extension is sloped for draining liquid into the spray chamber 441. As shown in Fig. 7, the top of the cabinet extension 549 is formed with upturned fastening flaps 555 which mate with the top framework 457 of the lower frame and with the guide rails 461 defining the aforementioned slot 463 for passage of shackles S.

The inner baffle plate 545 is secured to a pair of vertical flanges 561 on the inside of the cabinet extension 549. The outer baffle plate 547 is fastened to a peripheral flange 563 projecting laterally outwardly from the extension at its outer end. Each baffle plate 545, 547 has an opening 565, 567, respectively, for passage of animal carcasses therethrough. These openings are sized to be not substantially larger than necessary to accommodate the animal carcasses C passing into the cabinet so as to inhibit the escape of spray from the spray chamber 411. The two baffle plates 545, 547 are reversible for accommodating carcasses hanging in different orientations on the shackles. A drip shield 573 (Fig. 7) is attached to the exterior wall of the outer baffle plate 547. The entryway 415 and exitway 419 have slots therein (defined by flaps 555) aligned with the slot 463 defined by the guide rails 461 to permit unimpeded passage of shackles moving through the guide rails. The top 405 of the cabinet 171 comprises a pair of top cover panels 581 of sheet metal or the like having peripheral rims 583 which fit down into top openings 585 bounded by the top framework 457 of the lower frame 427 (Figs. 5, 6 and 8.) The top cover panels 581 are fastened to the top framework 457 in positions wherein they extend side by side the length of the cabinet. Adjacent sides of the two panels are spaced apart above the slot 463 defined by the guide rails 461. As illustrated in Fig. 8, the tops of the cover panels 581 slope toward the sides of the cabinet for efficient draining during operation of the spray system and when the cabinet is being cleaned.

Each spray cabinet 171 also includes a spray system or manifold generally indicated at 601 inside the cabinet for spraying liquid chemical, supplied by the mixing and delivery system 1 of the present invention, onto animal carcasses C as they are transported through the cabinet. In general, the spray system comprises a plurality of nozzles 605 (Figs. 8 and 11), each configured for spraying liquid chemical at a rate of about 0.05-0.3 gpm (gallons per minute) at a pressure preferably greater than 40 psig. These nozzles are suitably located to generate a chemical fog throughout the spray chamber 411 for continuously exposing substantially the entire surface of each animal carcass to liquid chemical as it is transported through the chamber from the entryway 415 to the exitway 419. It is important to note in this regard that for most efficient results, animal carcasses passing through the cabinet should be continuously exposed to fresh chemical spray to counteract the natural capacity of the carcasses to neutralize the chemical and render it less efficient.

Fig. 11 illustrates one possible sprayer configuration of the present invention. In this configuration, the spray nozzles 605 are mounted on a series of spray rings 611 and parallel connecting or header pipes 613 which form a cage structure. This system is designed to be installed in the spray chamber 411 so that the rings lie in upright planes extending side-to-side with respect to the chamber at intervals spaced along the chamber. (Three such rings are illustrated, but this number can vary.) The upper portion of each ring is split to have spaced apart ends which are connected to the header pipes 613. The header pipes are supported by suitable pipe hangers or the like engageable with the top framework 457 of the lower frame 427. The spray system formed by the rings 611 and header pipes 613 is connected to one of the branch delivery lines 165A-165D from the mixing and delivery system 1 described above. The spray rings 611 are sized and located for the passage of animal carcasses sequentially through the rings as the carcasses are transported through the cabinet from one end to the other. Each spray ring 611 is preferably formed from a single length of metal (e.g., stainless steel) conduit bent into a generally rectangular shape, although other shapes are possible. The ring can also be formed from several lengths of straight pipe connected by fittings.

Each spray ring 611 may have at least one spray nozzle 605 located on a lower portion of the ring for spraying in an upward direction to wet the bottom surfaces and interior surfaces (via the neck opening) of an animal carcass passing through the ring, and at least two (preferably four) spray nozzles 605 located on opposite side portions of the ring for spraying in generally lateral directions to wet opposite side surfaces of the animal carcass. A series of nozzles are located on the two header pipes 605 and/or the upper portions of the spray rings for spraying in a generally downward direction to wet the upper surfaces and interior surfaces (via the rectal opening) of the animal carcass. This arrangement ensures that chemical is sprayed on all surfaces of the carcass, both interior and exterior. The nozzles 605 can be fixed or mounted on ball joints to permit adjustment. Alternatively, suitable means may be provided for oscillating the nozzles. Regardless of how they are mounted, the nozzles 605 should be capable of spraying at the aforementioned low volumes to minimize the amount of chemical sprayed while still providing a sufficient quantity to effectively control bacteria. Suitable commercially available nozzles include Bete Fog model Nos. PJ20 and PJ15. These nozzles are capable of spraying low volumes of chemical to create the necessary "fog" or heavy mist in the spray cabinet to achieve desired results. The downwardly-directed nozzles 605 on the header pipes 613 are preferably, but not necessarily, fan spray nozzles such as a Spraying Systems model No. 2501. It will be understood by those skilled in this field that the type of nozzle 605 selected will depend on such factors as the flow rate to the cabinet 171 (e.g., up to about 6 gpm, and preferably about 2 gpm) , the number of nozzles (e.g., 21 per cabinet), the type of spray pattern desired (e.g., fan and/or cone), and the fluid pressure (e.g., preferably at least about 40-50 psi so conventional nozzles can be used) . Accordingly, the specific type or types of nozzle used will vary according to conditions. The important point to note is that the nozzles 605 should generate a spray which provides sufficient spray and fog in the cabinet to substantially continuously wet the interior and exterior surfaces of the carcasses passing through the spray chamber 411.

As noted above, nozzles 605 could be oscillating nozzles capable of oscillating in horizontal and/or vertical planes to achieve maximum coverage. The nozzles 605 could also be self-cleaning nozzles of the type which use air to mix with the liquid stream to reduce the risk of the nozzles becoming plugged.

An exhaust system, generally designated 631 in Fig. 4, is connected to the top cover panels 581 of the spray cabinet 171 for drawing air from the spray chamber 411 (thus reducing the pressure in the chamber) to further inhibit the escape of spray via the ends of the cabinet. The exhaust system comprises a plurality of air ducts 635 which are secured to the cover panels 581 of the cabinet and which communicate with the spray chamber through holes in the cover panels. These air ducts are connected to a high-pressure exhaust fan 641 (Fig. IC) which is operable to create a partial vacuum in the spray chamber (e.g., a vacuum of 2-4 in. of H₂0) . If desired, a single air duct system can be used for more than one cabinet 171, in which case a single exhaust fan 631 may be used to handle two or more spray cabinets, as illustrated in Fig. IC. Dampers 651 are provided in the air ducting 635 to control the flow of air from the cabinets (see Fig. IC) . Pressure switches 655 are provided in the ducting 635 to verify proper operation of the exhaust system.

The construction of the spray cabinet 171 described above is such that there is virtually no escape of spray or leakage from the cabinet. Liquid drains to the bottom 407 of the cabinet to the drainage system 519. Air is withdrawn through the top 405 of the cabinet. As a result, there is no need to separate air and liquid, making waste disposal easier and more economical. Also, the cabinet 171 is easy to clean by removing one or both side panels 485, and by swinging the bottom panel 505 down from either side of the cabinet, or by removing it entirely.

The length of the cabinet will vary, depending on the preferred length of time freshly applied chemical should reside on each carcass and the speed of the production line. However, to make fabrication as simple as possible, the cabinets of the present invention are modular in form. That is, they are constructed to have a standard length (e.g., five feet) and to be connected end to end as needed to provide the desired length of cabinet. For example, two modules may be connected end to end to handle a line speed of 70 carcasses per minute; three modules to handle a line speed of 91 carcasses per minute; and four modules to handle a line speed of 140 carcasses per minute. The preferred length of time freshly applied chemical should reside on each carcass is at least about 3 seconds, and preferably about 10 seconds .

Figs. 12 and 13 illustrates how first and second cabinet modules 171A, 171B can be sealingly connected end to end by using an annular connector such as a sheet metal rectangular connecting frame 675 of the type depicted in the drawing. This connecting frame has end faces defined by peripheral flanges 677 projecting laterally outwardly from the frame 675 at opposite ends of the frame. The first of these flanges 677 is sealingly engageable with the exit end of the first cabinet module 171A, and specifically with the lower frame 427 of the first cabinet module around the exit end opening 541 in the frame. The second flange 677 is sealingly engageable with the entry end of the second cabinet module 171B, and specifically with the lower frame 427 of the module around the entry end opening 541 in the frame. (The entryway and exitway at respective connected ends of the two modules are eliminated when connecting the modules 171A, 171B.) The arrangement is such that animal carcasses exiting the first cabinet module 171A pass through the connecting frame 675 before entering the second cabinet module 171B. Gaskets or other suitable seals 681 are provided between the end flanges 677 of the connecting frame and respective cabinet modules to seal against the escape of air and liquid. The connecting frame is fastened to the modules by suitable fasteners . In much the same fashion as the top of entryway 415 is shown split in Fig. 7, the top of the frame 675 is split and secured (e.g., welded) to the guide rails 461 on the outside of the slot 463 defined by the rails.

In accordance with another feature of this invention, the cabinet modules 171 described above are configured to be attached side-by-side with adjacent side panels 485 of the cabinets removed to provide a double- wide spray chamber capable of handling two production lines at one time. Such a configuration is illustrated in Fig. 14 which shows a first pair of cabinet modules 171A, 171B connected side-by-side to a second pair of cabinet modules 171C, 171D. In this configuration, a single double-wide bottom panel is used for two side-by- side cabinets (instead of two separate bottom panels 505) , thereby eliminating what would otherwise be a seam with a potential for leakage. The frames of the cabinets are sealingly connected side-by-side, as shown, by suitable fasteners and gaskets.

To operate the system of the present invention, a suitable number of modular spray cabinets 171 of the present invention are provided and, if necessary, connected to provide a spray chamber 411 of sufficient size to handle the required number of production lines and speeds. Each spray cabinet 171 is connected to a branch delivery line 165 of the mixing and delivery system 1 for delivery of chemical to the spray system of the cabinet.

Figure 15 is a schematic diagram of the system architecture of the system 1 of the invention. As noted above, the system is controlled by a programmable logic controller (PLC) 702, although it is contemplated that any computer, processor or other controller may be used to control the system 1. The PLC 702 has a plurality of analog inputs (Al) with alarms which are connected to the following: water pump flowmeter 103, water supply pressure monitoring device 101, blended stream pH measuring unit 175, base pump flowmeter 141, base supply temperature monitoring device 75, base tank level transmitter 73, acid pump flowmeter 141, acid supply temperature monitoring device 75, acid tank level transmitter 73, inlet pressure monitor 209 for spray cabinets #1-4 and chlorine dioxide monitors 321. These analog inputs have both high and low alarms so that the software or ladder diagram (described in Figs. 16-22) for running the PLC is programmed with minimums and maximums for the values for each of these analog inputs. In general, alarms may be indicated for high or low pH (e.g., a pH above 2.9 or below 2.5), loss of additives or water, low levels detected for the additive tanks, low flow detected for the blended stream of the additives and water, failure of the cabinet exhaust fans, failure of the shelter ventilation fan, clogging of the spray nozzles which would result in reduced flow rates, or unacceptable chlorine dioxide levels. The PLC does not include any analog inputs without any alarms, although it is not beyond the scope of this invention to include such.

The PLC monitors system operation via discrete or digital inputs (DI) with alarms as follows: flow switches 145 to verify base flow and to verify acid flow, exhaust fan inlet pressure switches 655 to verify exhaust system operation, and collection pan high level sensors 307 to indicate leaks being collected in the pan. The PLC 702 also monitors a plurality of discrete digital inputs with no alarms as follows: bird sensors 685 for monitoring the status of the four conveyors which are feeding the four spray cabinets, the spray cabinets liquid supply solenoid valves 201 (one for each line) , the acid tank solenoid-operated supply valve 33, and the base tank solenoid-operated supply valve 67.

Preferably, each bird sensor 685 may be any photoelectric sensor or other sensor, such as sensor model #42GOU-900A-OD. with reflector model #92-39 manufactured by Photoswitch (owned by Allen-Bradley) . The sensors 685 are located upstream of the cabinets 171 but are shown in Figures IC as adjacent the cabinets for convenience. The upstream location allows the sensors to detect carcasses and/or their movement as the processing line carries the carcasses to the cabinets 171 to be treated.

The PLC 702 also monitors the operation of several loop control modules via its analog inputs (Al) and controls these modules via analog outputs (AO) . As well as controlling these modules, alarms are indicated when the modules operate outside preset ranges . Water flow rate is the primary controlled variable. The flow control loop (203, 207, 208) maintains a substantially constant water flow rate to each of the spray cabinets. Flow controller 208 opens or closes valve 203 to maintain constant flow as indicated by flow monitor 207. The addition of chemicals will be proportional to the total water flow rate, base concentration, activator concentration, the speed of the processing line, i.e., the number of birds per minute being fed, and dosage per bird. The line speed is fixed for each processing line and programmed into the PLC 702 at the time of installation of the invention. The PLC is preprogrammed to calculate the required water to chemical ratio. The base pump speed controller 61 is controlled by the PLC 702 and operates at a rate equal to the water flow rate times a fixed ratio. The acid pump speed controller 27 is also controlled by the PLC 702 according to the water flow rate times a fixed ratio. The flow controller 208 for the four spray cabinets have a preset, fixed set point which is programmed into the PLC 702 prior to or at installation. It is contemplated that this set point could be changed remotely or by a field modification. The PLC 702 also controls several motor control modules via its digital inputs and digital outputs. In particular, the water pump 91 and exhaust fan 315 are directly controlled by the PLC and the base metering pump 57 and acid metering pump 21 are controlled by variable frequency drives 720 via a remote input/output link to the PLC. Part of the system architecture includes a plurality of local control push buttons and alarms 704. In particular, start/stop push buttons (not shown) are located at the production facility. The start/stop push buttons, for each line, control the blending (applicator) system. These buttons initiate and shut down chemical spray to each cabinet. The blending system will shut down if all lines are stopped. A common stop push button will also be located at the production facility and may be used to stop all lines in case of abnormal operation. The common stop push button will also shut down the blending process.

Several lights will be part of the alarms 704. A green indicating light at the production facility and at the building 243 will be used for system ON indication, and a yellow beacon light at the production facility will be used for alarm indications, process and chlorine dioxide high levels. A yellow beacon light at the shelter will be used for low chlorine dioxide thresholds (0.1 ppm) alarm indications. A red beacon light at the shelter will be used for high chlorine dioxide thresholds (0.3 ppm) alarm indications and for shut down indications. In addition, a horn may be used at the building 243 to provide an audible alarm warning to indicate low chlorine dioxide thresholds (0.1 ppm). Other control buttons which may be used include an emergency stop push button. In particular, two emergency stop push buttons may be used to kill power and shut down the blending system. One emergency stop button may be located at the shelter and the other at a remote location from the shelter. In addition, reset push buttons may be located at the shelter to reset the power shut down after high chlorine dioxide indications, emergency stops or ventilation fan failure. An alarm acknowledge push button may be located at the shelter to silence audible alarms. Finally, an on/off selector switch (not shown) may be used at the shelter to separately control the ventilation fan.

The PLC 702 is linked to a central station 706 as follows. The PLC 702 interfaces with a modem 708 which either selectively or constantly communicates with a modem 710 located at the central station 706. Transmitted data is handled by a data acquisition computer 712 which manipulates and stores the data in a database 714. It is also possible to control the system 1 from the central station 706 by a supervisory control computer 716 which interfaces with the PLC 702 via the modems 710 and 708. It is contemplated that the database may be accessed by a system for automatically refilling the tanks, such as the system described in the above noted co-owned, copending U.S. patent application Serial No. 08/636,289, filed April 23, 1996 for INTEGRATED SYSTEM MONITORING USE OF MATERIALS, CONTROLLING AND MONITORING DELIVERY OF MATERIALS AND PROVIDING AUTOMATED BILLING OF DELIVERED MATERIALS, incorporated herein by reference. The database 714 would provide information to the refilling system which information corresponds to the past and/or present level or usage level of the tanks 7 and 41 as indicated by the level signals provided by transmitters 73. In addition, the PLC includes 702 a human-machine interface (HMD 718 for permitting operators at the site to monitor and/or modify system operation.

Figure 16 is a simplified flow diagram illustrating operation of the system 1 with respect to monitoring of chlorine dioxide levels in the building 243 via monitors 321, treatment liquid pH levels via measuring unit 175, pressure ranges via pressure monitoring device 101 and monitors 209, temperature ranges via monitoring devices 75, and flow loops and ranges via meters 103 and 141. In addition, the levels of the tanks 7, 41 as indicated by level transmitters 73 and other parameters may also be monitored and could be a part of the flow diagram. For simplicity, monitoring of the tank levels and other parameters is not illustrated in Fig. 16. After initializing and start-up at step 802, the PLC 702 proceeds through five steps 804, 806, 808, 810 and 812 in order to determine the chlorine dioxide level, the pH level, the pressures, the temperatures and the flows of the system, as noted above. If any of these determinations indicate a parameter outside a preset range, the system proceeds to step 814 to indicate either an audible and/or visual alarm. In addition, insufficient acid or base flow at step 812 will initiate alarm 814 and a pump shutdown 815 and high chlorine dioxide levels at step 804 will initiate alarm 814 and a process shutdown 817. It is noted that some of these parameters (chlorine dioxide levels via monitors 321, pH levels via measuring unit 175, water pressure ranges via device 101, acid and base temperature ranges via monitoring devices 75, water, acid and base flow loops and ranges via meters 103 and 141, and acid and base tank levels via level transmitters 73) are system parameters whereas other parameters (cabinet inlet pressure via monitors 209 and carcass detection via sensors 685) are line parameters. For convenience, Figure 16 illustrates the parameters in sequential order. One of ordinary skill will readily recognize that separate subroutines for cabinet pressure and carcass detection could be implemented for each of several lines. It is noted that one important aspect of the invention is the ability to monitor and control flow in order to provide a constant flow rate to one or more operating cabinets 171, independent of each other. This is accomplished because the water, acid and base flow loops provide proportional amounts of water, acid and base to meet the demand of one to four cabinets, depending on how many are operating. In other words, the system design maintains constant, proportional flow of water, acid and base independent of the number of operating cabinets and independent of which cabinets are operating.

In addition, the PLC 702 executes a feed forward flow control loop 818, 820 (including an alarm 814) to maintain constant water flow. In fact, three flow control loops are employed for water, acid and base. For simplicity, only the water flow loop is illustrated. Also, it is contemplated that a feedback flow loop for water, acid and/or base may be used instead of or in addition to the feed forward loop illustrated for water. After all five parameters have been evaluated and the flow loop has been executed, the system proceeds to step 822 to determine whether any carcasses are detected on the processing line by infrared bird sensor 685. If no carcasses are detected, the system (or line) is inactivated at step 824. If carcasses are detected, the system proceeds to step 826 to determine whether the detected carcasses are moving. If no movement is detected, the system (or line) is inactivated at step 824. Otherwise, the detection of carcasses which are moving allows the system to proceed to step 828 where the system (or line) is either activated or continues to be activated. This process of Figure 16 is then repeated. Figure 17 is a diagram illustrating an overview of the process control definition for the system 1. The process is a single process cell with one continuous process unit. Normal operation is continuous. At step 852, the conveyor line for each spray cabinet must be running before starting the blending process system. The particular starting procedure for each conveyor is defined at the production facility and may vary from line to line. In general, it is preferable that the system be configured to assure that each and every carcass is treated with the anti-bacterial liquid. For example, the sensor 685 may be located upstream of the applicator such that initialization cycle of the system is less than the time it takes a carcass to travel from the sensor 685 to the cabinet 171. With this arrangement, as soon as a new carcass is detected, initialization is begun. Since the initialization cycle is less that the time it takes the new carcass to reach the cabinet 171, all new carcasses are treated. The system may also be configured to shut down if no carcass movement is detected for a preset period of time (e.g., 3 minutes). In this case, the sensor 685 may be located upstream such that the preset period of time is greater that the time it takes a carcass to travel from the sensor to the cabinet 171. When no carcass or no carcass movement is detected, the system continues to operate to allow all carcasses between the sensor and the cabinet to pass by the sensor and be treated in the cabinet by the antimicrobial liquid. Depending on PLC programming and other control factors, there may be some scenarios wherein untreated carcasses could pass through the applicator so that manual supervision and sorting of the system may also be desirable.

Referring again to Figure 17, when the conveyor is detected as being (ON) at step 852, the system enables the blending of the components and the process of treatment to start. Step 852 is followed by an initialization step at 854. Once the conveyor line is running, the blending system can be initialized by a local "start" push button or from the HMI 718. This will start the spray cabinets, exhaust fan 315 and water pump 91. After flushing of the lines, the blending system is ready to receive and treat birds.

The process control definition then proceeds to an active run step at 856 at which point carcasses such as birds are detected and the acid pump 21 and base pump 57 are started. After the birds are detected, the pumps start and the blended solution is then conveyed to the spray cabinets. It could take up to three minutes to convey the ^'blended solution to the spray cabinets. Therefore, as noted above, the bird sensor 685 for each line is located upstream a sufficient distance to allow the system to flush and convey the blended solution to the spray cabinets. For example, for a 70 bird per minute line, the sensor 685 would be located about 210 birds upstream of the cabinet. During operation, pH is monitored by unit 175. The system 1 continues in an active run mode according to step 856 unless no birds are detected for three minutes or no bird movement is detected for three minutes, in which case the system proceeds to idle step 858. If no birds are detected or moving for three minutes on all lines, then the system is placed in an idle mode and the base pump 57 and acid pump 21 are stopped. On a line-byline basis, if birds are not detected or not moving for three minutes (this amount may vary from plant to plant or line to line) , then the line will go to an idle mode and the feed of mixed liquid to the cabinet is discontinued by closing the solenoid controlled unit valve 201. This three minute interval should be of sufficient length to allow all birds between the sensor 685 and the cabinet 171 to be treated with liquid. For example, for a 70 bird per minute line, it the sensor is located about 210 birds upstream of the cabinet, three (3) minutes would be needed to permit all 210 birds between the sensor and the cabinet to be transported to the cabinet and treated before the line is shut down. At any time after a line is shut down, the system may initiate a water flush of the cabinet in the line until the bird sensor of the line again detects birds or birds' movement and return to the active run mode at step 856.

Each individual line can be stopped from local "stop" push buttons or from the HMI 718 so that the process control definition would proceed to shut down at step 860. In this step, the solenoid controlled inlet valve 201 for the particular line will be deactivated so that further flow of the antimicrobial liquid is inhibited and the solenoid controlled flush valve 225 will be opened to flush the cabinet with water. If all lines are stopped, then the blending system will stop after flushing the all the spray lines.

Figures 18A and 18B are logic diagrams illustrating a start-up sequence for programming the PLC used to control the system 1. The start-up sequence begins at step 902 for all four cabinets 171 in response to activation of the push buttons at the production facility or in response to a start-up signal from the HMI 718. At step 904, the PLC determines whether the conveyors of the line or lines which have been turned ON are moving. This can be determined by reading bird sensor 685 or by a separate input from the line to the PLC. If the line is not running, an alarm is indicated. Otherwise, the PLC proceeds to step 906 to start the shed exhaust fan(s) 315 and/or cabinet exhaust fan 641. Step 908 confirms that the exhaust fan(s) are operating and indicates an alarm if they are not. Step 910 confirms that the cabinet exhaust fan(s) inlet pressure as indicated by pressure switch 655 is above a minimum or indicates an alarm. The PLC then proceeds to step 912 to confirm that the upstream water pressure of the pump 91 as detected by device 101 is within the preprogrammed acceptable range or an alarm is indicated.

Assuming sufficient fan inlet and upstream water pressure, the PLC proceeds to step 914 to open the solenoid valves 201 which feed the mixed antimicrobial liquid to cabinets 1-4 and then proceeds to step 916 to enable the individual flow controllers 208 of each cabinet. At step 918, the water pump 91 is started and step 920 confirms that it is operating via flow sensor 103; otherwise, an alarm is indicated. Now that pump 91 is operating, step 922 again confirms sufficient upstream water pressure via pressure device 101 or indicates an alarm and step 924 confirms sufficient downstream water flow within the preset range as detected by flow sensor 103 or an alarm is indicated which stops the water pump at step 926.

If step 928 confirms that the water flow to each cabinet as detected by flow monitors 207 is within an acceptable range, a five minute delay is initiated at step 930 to flush the system. Thereafter, when birds are detected at step 932 by detector 685, the PLC proceeds to step 934 to calculate the acid ratio according to the water flow rate as detected by flowmeter 103. Next, the PLC proceeds to step 936 to set the speed of the acid pump 21 and then to step 938 to set the acid pump stroke via electronic controller 27 based on the calculated acid ratio. At step 940 (Fig. 18B) , the solenoid controlled acid supply valve 33 is opened and at step 942 the PLC energizes the acid pump 21. Step 944 confirms that the acid pump is working by checking flow switch 145. If it is not, the PLC proceeds to step 946 to deenergize the pump 21, close the supply valve 33 and indicate an alarm. Otherwise, the PLC proceeds to step 948 to confirm that the acid liquid is flowing within the proper range by reading acid flow monitor 141 or the pump 21 is stopped, the valve 33 is closed and an alarm is indicated at step 950. If the acid liquid is flowing and after a ten second delay at step 952, the base ratio is calculated at step 954 according to the water flow rate as detected by water flowmeter 103. Next, the speed of the base pump 57 is set at step 956 and the base pump stroke is set at step 958 via electronic controller 61 based on the calculated base ratio.

The PLC then proceeds to step 960 to open the base liquid solenoid controlled supply valve 67 and to step 962 to start the base pump 57. Step 964 confirms that the base pump is working by checking flow switch 145 or the PLC proceeds to step 966 to stop the pump 57, close the valve 67 and indicate an alarm. Otherwise, the base flow is confirmed to be within range at step 968 by reading base flow monitor 141. If the flow is outside the acceptable range, the PLC proceeds to step 970 to stop the pump 57, close the valve 67 and indicate an alarm. Otherwise, the PLC initiates a delay (e.g., 10 seconds) at step 972 and proceeds to step 974 to read the pH measuring unit 175 and confirm that the pH of the blended liquid is within an acceptable range. If it is not, an alarm is indicated; otherwise, the PLC proceeds to continuously monitor the blending process at step 976 as generally illustrated in Figure 16 and the start-up sequence is complete.

Figure 19 illustrates the idle sequence for the system when all lines are will be idled because of empty shackles on all lines. Assuming that the system has not received a manual "stop" indication at step 1002 (to implement the shutdown sequence) and that all four conveyors are operating at step 1004, the PLC confirms that the shackles are empty at step 1006 by reading bird detector 685 and then executes a sixty second delay at step 1008. If any birds are detected after the sixty second delay at step 1010, the PLC proceeds to step 918 of Figure 18A to start the water pump 91. Otherwise, the PLC proceeds to step 1012 to execute a two minute delay confirming that a preset period has passed without detecting birds. The preset period may equal the effective shelf life of the mixed liquid components. Thereafter, steps 1014, 1016, 1018 and 1020 execute a purge cycle to stop the base pump 57, close the base supply valve 67, stop the acid pump 21, and close the acid supply valve 33, respectively. After a ten minute delay at step 1022 to flush the system, the water pump 91 is stopped at step 1024 ending the idle cycle for the system. This ten minute delay approximately equals the period during which the mixed liquids in the filters are purged. If only a particular line is to be idled because of empty shackles on the particular line, PLC follows the sequence of Figure 20. Assuming the system is not manually stopped at step 1102 (to implement the shutdown sequence) and the particular conveyor is operating at step 1104, the PLC looks at the bird detector 685 to confirm empty shackles at step 1106. After a sixty second time delay at step 1108, the PLC confirms that no birds have been detected at step 1110. If birds are detected, the PLC proceeds to step 1112 to enable the controller 208 of the particular cabinet, then to step 1114 to close the flush valve 225 and then to step 1116 to open the microbial liquid flow valve 201. If no birds have been detected at step 1110, the PLC executes a two minute delay at step 1118, and then opens to 100% the valves 203 at step 1120, closes the cabinet microbial liquid supply valve 201 at step 1122 and opens the flush valve 225 at step 1124. This completes the idle sequence for a particular line.

Figure 21 illustrates the shutdown sequence for all conveyor lines. After receiving a manual signal to idle all cabinets at step 1202, the PLC executes steps 1204, 1206, 1208 and 1210 to stop the base pump 57, close the base supply valve 67, stop the acid pump 21, and close the acid supply valve 33, respectively. After a ten minute delay at step 1212 to flush the system with water, the PLC stops the water pump 91 at step 1214, disables all cabinet controllers 208 at step 1216, closes all flow valves at step 1218 and closes all cabinet valves at step 1220. The exhaust fan 631 is stopped at step 1222 to complete the shutdown sequence for the entire system.

If only a single line (e.g., cabinet 1) is being shut down, the PLC executes the steps of Figure 22 in response to the signal at step 1252 from a push button indicating that cabinet 1 should be stopped. The PLC opens to 100% the cabinet flow valve 203 for cabinet 1 at step 1254, closes the liquid supply valve 201 for cabinet 1 at step 1256, and opens the flush valve 225 for cabinet 1 at step 1258. Thereafter, the cabinet lights are turned off at step 1260. In general, the invention comprises a system for controlling and monitoring carcass processing line and for recording and reporting data corresponding to various conditions and/or parameters (as noted above) of the carcass processing line. The carcass processing line includes a treatment station (such as cabinet 171) at which the carcasses are treated such as by washing or by chilling with a treatment liquid. A treatment sensor for monitoring a condition (or parameter) of the treatment liquid used at the treatment station or of the line itself. The treatment sensor provides a treatment signal to the PLC 702 indicating the condition of the treatment liquid, and the controller indicates an alarm when the treatment signal indicates that the condition of the treatment liquid is outside an acceptable range. In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Claims

ClaimsWHAT IS CLAIMED IS

1. A spray cabinet system for spraying animal carcasses with an anti-microbial liquid chemical, said system comprising: a cabinet having opposite sides, a top and a bottom defining a spray chamber; an entryway at an entry end of the cabinet for entry of animal carcasses into the spray chamber; an exitway at an exit end of the cabinet for exit of animal carcasses from the spray chamber; a spray system inside the spray chamber for spraying said liquid chemical onto animal carcasses as they are transported through the cabinet; said entryway and exitway being sized not substantially larger than necessary to accommodate said animal carcasses so as to inhibit the escape of spray from the spray chamber; a drain in the bottom of the cabinet for draining liquid from the cabinet; and an exhaust system connected to the top of the cabinet and communicating with the spray chamber for drawing air out of the spray chamber and reducing the pressure in the spray chamber thereby further to inhibit the escape of spray from the spray chamber via said entryway and exitway.

2. A spray cabinet system as set forth in claim 1 wherein said cabinet comprises a frame assembly, a pair of side panels at opposite sides of the cabinet, a bottom panel at the bottom of the cabinet, and a plurality of quick-operating fasteners for removably attaching the side panels to the frame assembly.

3. A spray cabinet system as set forth in claim 2 wherein said frame assembly defines a pair of side frame openings at opposite sides of the frame, and a knife edge attached to the frame assembly around an inner periphery of each side frame opening, each side panel having a gasket thereon engageable with said knife edge for sealing around said frame opening.

4. A spray cabinet system as set forth in claim 2 further comprising a plurality of connections connecting the bottom panel of the cabinet to the frame assembly so that the bottom panel may be swung from a closed position down to an open position or removed from the cabinet entirely.

5. A spray cabinet system as set forth in claim 1 wherein said frame assembly comprises an upper frame projecting above the top wall of the cabinet configured for engaging an overhead rail system or other structure so that the cabinet can be suspended therefrom.

6. A spray cabinet system as set forth in claim 5 wherein a side part of the upper frame is removable to facilitate installation of the upper frame on said rail system or other structure.

7. A spray cabinet system as set forth in claim 5 wherein said frame assembly further comprises a lower frame supporting the cabinet, the lower frame being vertically adjustable relative to the upper frame to vary the elevation of the cabinet.

8. A spray cabinet system as set forth in claim 1 wherein said entryway comprises first and second upright spaced apart baffle plates, each baffle plate having an opening therein sized not substantially larger than necessary to accommodate said animal carcasses so as to inhibit the escape of spray from the spray chamber while allowing for the passage of animal carcasses into the spray chamber.

9. A spray cabinet system as set forth in claim 8 wherein said exitway comprises first and second upright spaced apart baffle plates, each baffle plate having an opening therein sized not substantially larger than necessary to accommodate said animal carcasses so as to inhibit the escape of spray from the spray chamber while allowing for the passage of animal carcasses into the spray chamber.

10. A spray cabinet system for spraying animal carcasses with an anti-microbial liquid chemical, said system comprising: a cabinet having opposite sides, a top and a bottom defining a spray chamber; an entryway at an entry end of the cabinet for entry of animal carcasses into the spray chamber; an exitway at an exit end of the cabinet for exit of animal carcasses from the spray chamber; and a spray system inside the spray chamber for spraying said liquid chemical onto animal carcasses as they are transported through the cabinet; said spray system comprising a plurality of low- volume spray nozzles, each configured for spraying said liquid chemical at a rate of about 0.05-0.3 gpm, said spray nozzles being configured and operable to generate a chemical fog throughout the spray chamber for continuously exposing each animal carcass to said liquid chemical as it is transported from said entry opening to said exit opening.

11. A spray cabinet system as set forth in claim 10 wherein said spray nozzles are mounted on a series of spaced apart spray rings connected by connecting pipes, said spray rings lying in upright planes in the spray chamber and being sized and located for the passage of animal carcasses sequentially through the rings as the carcasses are transported through the cabinet, each spray ring having at least two spray nozzles located on opposite side portions of the ring for spraying in generally lateral directions to wet opposite side surfaces of said animal carcasses, and a series of spray nozzles located along the connecting pipes and/or on upper portions of the spray rings for spraying in a generally downward direction to wet upper and interior surfaces of the animal carcasses.

12. A method of applying an anti-microbial liquid chemical to animal carcasses, said method comprising: providing a spray cabinet having an enclosed spray chamber and a plurality of spray nozzles oriented for spraying said liquid chemical into the spray chamber; spraying liquid chemical through said spray nozzles at a rate of about 0.05-0.3 gpm per nozzle to generate a chemical fog throughout the spray chamber; and transporting animal carcasses through the spray chamber while said chemical fog is being generated thereby to continuously expose each animal carcass to said liquid chemical as it is transported through the spray chamber.

13. A method as set forth in claim 12 wherein said liquid chemical is delivered to said spray nozzles at pressure of more than about 40 psig.

14. A method as set forth in claim 12 wherein each animal carcass is exposed to said chemical fog for at least about 3 seconds.

15. A method as set forth in claim 12 wherein said chemical fog is of substantially uniform density throughout the entire spray chamber.

16. A modular spray cabinet system for spraying an anti-microbial liquid chemical on animal carcasses, said system comprising: a plurality of cabinet modules; each cabinet module comprising a frame and a plurality of panels mounted on the frame defining a spray chamber for passage of animal carcasses therethrough, the cabinet module having an entry end configured for entry of animal carcasses into the spray chamber and an exit end configured for exit of said carcasses from the spray chamber; and an annular connector for sealingly connecting first and second cabinet modules end to end, said connector having a first end face sealingly engageable with the exit end of the first cabinet module and a second end face sealingly engageable with the entry end of the second cabinet module whereby animal carcasses exiting the first cabinet module pass through said connector before entering the second cabinet module.

17. A modular spray cabinet system as set forth in claim 16 wherein each cabinet module comprises a bottom panel mounted on the frame for movement from a closed position to an open position to allow cleaning of the cabinet modules.

18. A modular spray cabinet system as set forth in claim 16 wherein each cabinet module comprises a pair of opposite side panels removably mounted on the frame by quick-operating fasteners.

19. A modular spray cabinet system as set forth in claim 18 wherein said cabinet modules are configured to be attached side-by-side with adjacent side panels of the cabinets removed to provide a double-wide spray chamber.

ΓÇó20. A system for mixing and delivering an antimicrobial liquid chemical tc an application system for applying the liquid chemical to animal carcasses, said mixing and delivery system comprising: a first tank for holding a first component of said liquid chemical in concentrated form; a second tank for holding a second component of said liquid chemical in concentrated form; a water supply system; a first pump for pumping said first component from the first tank to the water supply system to provide a diluted first component; a second pump for pumping said second component from the second tank to the water supply system to provide a diluted second component; at least one static mixer having an inlet for receiving said diluted first and second components, and an outlet, said mixer being operable to thoroughly mix the diluted first and second components to provide a substantially homogeneous mixture of said anti-microbial liquid chemical; and a chemical delivery line for delivering said homogeneous mixture from the outlet of the mixer to said application system.

21. A mixing and delivery system as set forth in claim 20 wherein said chemical delivery line is free of any substantial interruptions in the line which would tend to interrupt the uniform flow of said homogeneous mixture .

22. A mixing and delivery system as set forth in claim 20 further comprising dampeners downstream from said first and second pumps and upstream from the mixer to dampen any pulsing of liquid pumped by the pumps.

23. A mixing and delivery system as set forth in claim 20 wherein said water supply system comprises a water line connecting a water source to the inlet of the mixer, said mixing and delivery system further comprising a first supply line connecting said first pump to the water line upstream from the mixer and a second supply line connecting said second pump to the water line at a location upstream from the mixer and downstream from the first supply line.

24. A method of mixing and delivering an antimicrobial liquid chemical to an application system for applying the liquid chemical to animal carcasses, said method comprising: holding in a first tank a first component of said liquid chemical in concentrated form; holding in a second tank a second component of said liquid chemical in concentrated form; pumping said first component from the first tank and diluting it to provide a diluted first component; pumping said second component from the second tank and diluting it to provide a diluted second component, delivering said diluted first and second components to the inlet of a static mixer; mixing said diluted first and second components in said static mixer to provide a substantially homogeneous mixture of said anti-microbial liquid chemical; and delivering said homogeneous mixture from an outlet of the mixer to said application system for applying the mixture to said animal carcasses.

25. A method as set forth in claim 24 further comprising dampening the flow of said diluted first and second components upstream of the mixer to diminish any pulsing of the flow.

26. A system for treating animal carcasses being transported along a processing line comprising: a sensor positioned along the processing line for monitoring the movement of animal carcasses being transported along the processing line and generating a carcass movement signal representative thereof; an applicator for applying an anti-microbial liquid chemical to each of the animal carcasses as they are transported along the processing line; and a controller receiving the carcass movement signal and controlling the applicator in response to the carcass movement signal to thereby apply the anti-microbial liquid chemical to each of the transported animal carcasses as a function of the animal carcass movement signal generated by the sensor.

27. The system of claim 26 wherein the applicator includes a cabinet comprising: a cabinet enclosing a portion of the processing line defining a substantially enclosed spray chamber and enclosing the animal carcasses as they are transported through the spray chamber; and a spray system inside the spray chamber for spraying the liquid chemical onto animal carcasses as they are transported through the cabinet, said spray system responsive to the controller to spray the liquid chemical onto each of the enclosed animal carcasses as they are transported through the spray chamber.

28. The system of claim 27 wherein the controller deactivates the spray system when the carcass movement signal indicates no carcasses have passed the sensor for a first preset period of time or when the carcass movement signal indicates no movement of carcasses for a second preset period of time.

29. The system of claim 26 further comprising a mixing system for mixing first and second chemicals to form the anti-microbial liquid chemical and wherein the controller controls operation of the mixing system.

30. The system of claim 29 wherein the mixing system includes a mixer within which the first and second chemicals are mixed before application, wherein the mixed anti-microbial liquid chemical has a predetermined period of effectiveness, and wherein the controller controls the mixing system to purge the mixer of mixed liquid chemical when the mixed liquid chemical in the mixer is older than the predetermined period.

31. The system of claim 29 wherein the sensor is located upstream of the applicator such that an initialization cycle of the system is less than the time it takes a carcass to travel from the sensor to the applicator and wherein a preset period of time to shutdown or flush the system is greater that the time it takes a carcass to travel from the sensor to the applicator.

32. The system of claim 29 wherein the first and second chemicals are stored in first and second tanks, respectively, further comprising a first level sensor providing to the controller a first level signal indicating a level of the first tank and a second level sensor for providing to the controller a second level signal indicating a level of the second tank, and wherein the controller provides an alarm signal in the event that the level of the first tank as indicated by the first level signal is below a first minimum or in the event that the level of the second tank as indicated by the second level signal is below a second minimum.

33. The system of claim 29 wherein the first and second chemicals are stored in first and second tanks, respectively, further comprising a first level sensor providing to the controller a first level signal indicating a level of the first tank and a second level sensor for providing to the controller a second level signal indicating a level of the second tank, and wherein the controller provides to a system for refilling the tanks information corresponding to the level of the first tank as indicated by the first level signal and corresponding to the level of the second tank as indicated by the second level signal.

34. The system of claim 26 wherein the processing line includes a treatment station at which the birds are treated with a treatment liquid and further comprising a treatment sensor for monitoring a condition of the treatment liquid used at the treatment station or a component of the liquid, said treatment sensor providing a treatment signal to the controller indicating the condition of the treatment liquid, and wherein the controller indicates an alarm when the treatment signal indicates that the condition of the treatment liquid or its component is outside an acceptable range.

35. The system of claim 34 wherein the treatment sensor comprises a pH sensor, a flow sensor, a temperature sensor or a pressure sensor for monitoring the pH, flow rate, temperature or pressure, respectively, relating to the treatment liquid or its component.

36. The system of claim 26 further comprising a flow sensor for sensing the flow rate of the liquid or a component thereof and a pump controlled by the controller in response to the flow sensor for pumping the liquid or its component within an acceptable range.

37. The system of claim 26 further comprising a pump for pumping a first component of the liquid, a water supply for supplying water to be mixed with the first liquid to supply the anti-microbial liquid, a water flow sensor for sensing the flow rate of the water, and wherein the controller controls the first pump to pump the first liquid at a rate which is a function of the sensed water flow rate.

38. The system of claim 37 further comprising a first component flow sensor for sensing the flow rate of the first component and the first component pump is controlled by the controller in response to the first component flow sensor for pumping the first component within an acceptable range.

39. The system of claim 26 further comprising a sensor for sensing an environmental condition of the system, such as C10₂ levels, and indicating an alarm when the sensor indicates an unacceptable level.

40. A system for treating animal carcasses being transported along a processing line including a treatment station at which the carcasses are treated, said system comprising: an applicator for applying a liquid to each of the animal carcasses as they are transported along the processing line; a controller; a treatment sensor for monitoring a condition of a treatment liquid used at the treatment station or a component of the liquid, said treatment sensor providing a treatment signal to the controller indicating the condition of the treatment liquid or its component; and an alarm responsive to and activated by the controller when the treatment signal indicates that the condition of the treatment liquid or its component is outside an acceptable range.

41. The system of claim 40 wherein the treatment sensor comprises a pH sensor, a flow sensor, a temperature sensor or a pressure sensor for monitoring the pH, flow rate, temperature or pressure, respectively, relating to the treatment liquid or its component.

42. A method for treating animal carcasses being transported along a processing line comprising the steps of: monitoring the movement of animal carcasses being transported along the processing line; applying an anti-microbial liquid chemical to each of the animal carcasses as they are transported along the processing line; and controlling the amount of the anti-microbial liquid chemical applied during the applying step in response to the monitoring step to thereby apply the anti-microbial liquid chemical to each of the transported animal carcasses as a function of the monitored animal carcass movement .

43. A system for treating animal carcasses being transported along a processing line including a treatment station at which the carcasses are treated, said system comprising: an applicator for applying a liquid to each of the animal carcasses as they are transported along the processing line; a controller; and a flow controller responsive to the controller for controlling a flow rate of a treatment liquid used at the treatment station or for controlling a flow rate of a component of a treatment liquid used at the treatment station.

44. The system of claim 43 wherein the flow controller comprises a flow loop including a flow sensor providing a signal indicative of flow to the controller and a variable pump controlled by the controller in response to the signal provided by the flow sensor, said loop maintaining a substantially constant flow rate, and further comprising an alarm responsive to and activated by the controller when the flow sensor indicates that the flow rate of the treatment liquid or its component is outside an acceptable range.

45. The system of claim 43 further comprising a water supply for supplying water, a base supply for supplying a base and an acid supply for supplying an acid, wherein the applicator comprises a plurality of spray systems receiving a mixture of the acid, the base and the water for treating the carcasses and wherein each of the supplies includes a flow loop for maintaining the flow rate of the water, the base and the acid to the spray systems proportional to each other and independent of the number of spray systems and independent of the number of operating spray systems .