Abstract:
A portable batch pasteurizer for pasteurization or other heat treatment of contained fluids for consumption by animals or humans provides a heat transfer coil through which hot or cold fluids are pumped to heat or cool the fluid in which it is immersed. An impeller circulates the fluid in which the fluid is contained to ensure even heating or cooling.

Description:
REFERENCE TO RELATED APPLICATION 
     This application claims priority from Applicant&#39;s provisional application, U.S. Ser. No. 60/161,041, for BATCH PASTEURIZER FOR FLUIDS NOT FOR HUMAN CONSUMPTION, filed Oct. 25, 1999, which application is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to apparatus for pasteurizing or heat treating fluid products for consumption by animals or humans. 
     2. Description of the Relevant Art 
     Since the dawn of history, various methods and apparatus have been devised for the heat treatment of foodstuffs for human and animal consumption, including cooking, pasteurization and sterilization. Both pasteurization and sterilization have been used with milk and related products. U.S. Pat. No. 4,310,476 provides in columns 1 to 5 an extensive discussion of pasteurization and sterilization of milk, which is incorporated herein by reference. Column 30 of the same patent identifies legal U.S. standards for milk pasteurization, which are also incorporated by reference. 
     Dairy farmers and other producers of foodstuffs such as milk are often required to transport their produce to central plants for processing including pasteurization or sterilization and packaging. In less advanced countries, modern processing plants may be unavailable or inaccessible, so that dairy products must be utilized locally, with whatever processing is available. Excess milk may be used on the farm for feeding calves or other livestock, but may spoil or transmit disease if not pasteurized. There is an apparent need for portable, economical apparatus for pasteurizing such milk on site to permit its safe use for feeding calves and the like. There is also a need for portable, simple and economical apparatus for processing milk at or near the source in less advanced countries for both human and animal consumption. 
     Numerous patents disclose methods and apparatus for sterilizing food enclosed in containers. For example, U.S. Pat. No. 5,424,087 discloses methods of sterilizing canned food in a sterilizing kettle, using hot water for preheating and steam for sterilization. 
     U.S. Pat. No. 4,739,699 discloses apparatus for pasteurizing or sterilizing edible foodstuffs in containers. 
     U.S. Pat. No. 2,082,460 discloses apparatus for sterilizing and subsequently cooling food in closed containers, using a form of pressure cooker. 
     U.S. Pat. No. 5,280,748 discloses apparatus for uniformly cooking packaged foods in a “cook/chill” tank in which hot water is circulated to cook the food, then cold water is circulated to provide rapid cooling. 
     U.S. Pat. No. 5,080,164 discloses a process and device for heat treatment in continuous flow of a product mixture containing solids in liquid (i.e., a slurry), using a combination of heat exchangers to heat and then cool the slurry. 
     U.S. Pat. No. 3,780,644 discloses a mobile milk processing system mounted upon a motor vehicle, providing for field pasteurization, homogenization and packaging of raw milk. Water is heated or cooled and circulated as a heating and cooling medium. This system is intended to overcome the disadvantages of central processing plants which process milk in continuous flow. 
     U.S. Pat. No. 5,209,157 discloses a plant for manufacturing dairy preparations based upon skim milk and vegetable oils. A heater provides for brief heating and cooling of the product prior to packaging. 
     U.S. Pat. No. 4,534,986 discloses a system for the indirect “ultra-high” heat treatment of liquids such as milk with minimal thermal damage. 
     U.S. Pat. No. 4,515,823 discloses a process and apparatus for separation of raw milk into cream and skim milk, the latter of which is pasteurized and cooled by regenerative heat exchange in heat exchangers. 
     U.S. Pat. No. 4,446,781 discloses a process and apparatus for mechanical/thermal treatment of fluids such as melted cocoa masses, which can include sterilization and pasteurization. 
     U.S. Pat. No. 5,360,055 discloses a method and apparatus for heat treating fluid products such as milk, including a counter current heat exchanger. 
     U.S. Pat. No. 5,443,857 discloses a method and apparatus for sterilizing milk based liquid products, including indirect preheating and final heating to sterilization temperature by direct steam injection, followed by flash-cooling. 
     U.S. Pat. No. 3,973,048 discloses a method and apparatus for sterilizing liquids by brief heating, involving compression and pressure reduction to transfer heat and attain sterilization temperatures. 
     U.S. Pat. No. 4,738,302 discloses apparatus for heat-treating liquid products including series-connected multi-tube heat exchangers for heating and cooling the products. 
     U.S. Pat. No. 4,432,276 discloses apparatus for heating, pasteurizing and sterilizing fluid foodstuffs in which the substance to be heated is brought in direct contact with a heating fluid. 
     U.S. Pat. No. 4,446,778 discloses a pasteurization system for dairy farming products, including several basins wherein the pasteurization cycle is effected in sequence, the heat taken from one basin during its cooling phase being used to heat at least one other basin. A refrigerating circuit, heat pump and heat exchanger are used to heat and cool the basins. 
     U.S. Pat. No. 4,310,476 discloses apparatus for treating fluids at sterilization temperatures in which the fluid is heated by direct contact with steam while it is in the form of a thin, free-falling film or stream. 
     Most of these patents disclose apparatus and methods for the continuous processing of milk or other foodstuffs, and most of these systems are complicated and expensive. There remains a need for a simple, economical portable apparatus for batch processing of milk on dairy farms and the like. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide portable apparatus for the batch pasteurizing or heat treatment of liquid products in various locations, especially food products for consumption by animals or humans. Another object of the invention is to provide such portable apparatus which can be used with typical hot and cold tap water and electrical current available in dairy barns and the like. Another object is to provide for convenient field pasteurization of excess dairy products, which can then be fed to calves or other young livestock with reduced chances for the spread of disease. Still another object of the invention is to provide apparatus that can be quickly and effectively cleaned between uses to minimize health hazards. Yet another object of the invention is to provide portable apparatus of various sizes to meet the needs of diverse dairy sites. A further object is to fabricate portable apparatus from various commercially available components to provide units having varied sizes and capabilities. Still another object is to provide programmable time-temperature profiles to accommodate various processing needs. A further object is to provide a system which will allow about a sixty minute heating/cooling cycle for typical volumes of milk. A final object is to simplify the design and assembly of the apparatus so that the average dairyman can operate and service the unit with minimum downtime. 
     These and other objects and advantages are attained by apparatus of the present invention, comprising apparatus for the batch heating and cooling of fluids in bulk containers, comprising: 
     at least one heating/cooling coil to be inserted into the fluid to be heated and cooled; 
     at least one impeller to circulate the fluid to be cooled around the heating/cooling coil; 
     connections for sources of pressurized heating and cooling fluids; 
     temperature sensing means for measuring the temperature of the fluid to be heated and cooled; 
     valve means and switching means for successively turning on and off the heating and cooling fluids; 
     thermostat and control means for shifting from heating to cooling fluids in the coil when the treated fluid has been at the preset temperature for a sufficient time, and for turning off the cooling fluid to terminate a cycle when the treated fluid has attained the desired cooled temperature. 
     In preferred embodiments, the apparatus comprises a dome top fastened to the heating/cooling coil and the impeller shaft, the dome top being so dimensioned so that it can be fastened to the top of the container holding the fluid to be treated and thus protect the fluid from the atmosphere. Heating and cooling means can be provided to adjust the temperature of the heating and cooling fluids. Preferably, at least one pump is provided to direct the heating and cooling fluids through the coil. The heating and cooling fluids can either be returned to their sources for reuse or directed to drains. Means can be provided to conveniently hoist the apparatus out of the container of fluid treated, and to lower it in for a treatment cycle. Means are provided for efficient cleaning of the coil and other components between cycles. 
     Further in accordance with the invention, methods are provided for carrying out heat treatment processes such as pasteurization of dairy products using the apparatus of the invention, comprising steps of: 
     inserting the heating/cooling coil into a container of fluid to be treated; 
     attaching the dome top to the container to separate the fluid from the atmosphere; 
     activating the impeller to circulate the fluid to be treated about the coil; 
     directing heating fluid through the coil for a period effective to raise the fluid to be treated to a predetermined treatment temperature and hold it there for a predetermined time; 
     shutting off the heating fluid and promptly directing cooling fluid through the coil to quickly reduce the temperature of the treated fluid to a stable lower temperature for use or storage; 
     shutting off the cooling fluid to complete the cycle; and 
     removing the apparatus from the container of treated fluid. 
     By “portable” it is meant that the apparatus can be moved from place to place with relative ease, using manpower or simple lifting/hauling devices, and can be employed wherever suitable sources of electrical power and heating/cooling fluids are available. Such apparatus can be used in various dairy barns or other facilities at a single site and moved from site to site as well. By “bulk” containers it is meant that the fluids to be treated are contained in open containers allowing access to the apparatus of the invention, in contrast to sealed containers such as tin cans. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the invention and many of the objects and advantages thereof will be readily obtained by perusing the following detailed description and appended claims in combination with the accompanying drawings, wherein: 
     FIG. 1 is an exploded perspective view of the apparatus of the invention and a fluid container; 
     FIG. 1A is a side perspective view of an adaptive collar for the apparatus. 
     FIG. 2 is a perspective view of the apparatus alone; 
     FIG. 3 is a schematic diagram of a control system for the apparatus; 
     FIG. 4 is a detailed view of the switch/indicator panel; 
     FIG. 5 is a perspective view of the underside of the dome top of the apparatus; 
     FIG. 6 is a rear perspective view of the dome top showing hose connections; 
     FIG. 7 is a top perspective view of the chassis plate showing the impeller motor and electrical connections; 
     FIG. 8 is a detailed perspective view of the controller components mounted on the chassis plate; 
     FIG. 9 is a perspective view of typical inline heater; 
     FIG. 10 is a side view of a cleaning system for the apparatus; and 
     FIG. 11 is a side view of a wall bracket and support system permitting the apparatus to be transferred from one container to another alongside. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Although a preferred embodiment of the present invention has been designed for pasteurizing milk on dairy farms and the like, and the invention will be discussed in that context, systems within the scope of the invention can be used for processing or heat treating all sorts of fluid materials. The fluids will normally be liquids of low to moderate viscosity such as milk, but can also be more viscous dairy products such as ice cream mix or cheeses. Naturally, the characteristics of the material to be treated must be studied and understood before effective heat treatment can begin. For example, it is necessary for each product to determine the appropriate temperature-time relationships for optimum treatment. It is well known that the pasteurization or sterilization of milk and milk products involves a delicate balance between providing enough heat (through specified combinations of time and temperature) to kill target microbes without adverse effects on the flavor and other characteristics of the product. Different products, and even milk from various species such as goats, will require different temperature-time profiles for optimum treatment. Generally, the best results with milk products are obtained by brief heating at relatively high temperatures, followed by prompt and fast cooling. The apparatus of the present invention can be adjusted and programmed to provide heat treatments, including cooking, pasteurization or sterilization treatments, for a variety of milks and milk products (e.g., cream, reconstituted milk, ice cream mixes, puddings, candies and condensed or evaporated milk), fruit juices, ciders, fermented beverages such as beer and wine, yeast and meat extracts, slurried materials such as soups and stews, vegetable oils and chemical preparations. Thus, while a preferred embodiment will be disclosed for the pasteurization of cow&#39;s milk, the broad capabilities of the apparatus and methods disclosed should be kept in mind. 
     Turning now to the drawings, FIG. 1 illustrates a batch pasteurizer  16  of the invention partially inserted into a container  40  which holds a fluid to be heat treated (not shown). In the dairy context, container  40  can be a 55 or 20 gallon drum; the pasteurizer  16  can be sized or adapted to fit various types and sizes of containers which may be encountered in the field, with volumes ranging from about 10 to 250 gallons. Such containers can be any standard product designed for dairy farm use, but are preferably made of stainless steel or durable plastics such as fiberglass, polypropylene, polyethylene, nylon or polytetrafluoroethylene (Teflon™), which are light and can be cleaned effectively. The containers preferably include a spigot or other liquid transfer means near the bottom to facilitate transfer of the treated liquid into buckets or other secondary containers. Hoisting ring  18  (an eye bolt) provides a connection for lifting and transporting the apparatus to a position where it can be lowered into an open container for use. Such a unit is portable in that it can be used at various stations within a dairy barn or other site, or moved from site to site. A typical dairy unit should weight about fifty pounds, but the weight will vary according to size and materials. 
     Dome top  19  is fabricated to contain connections for heating and cooling fluids (discussed below), a motor-driven impeller and control systems and to position the heating/cooling coil and the impeller on its shaft. The dome top  19  is dimensioned to fit the top of container  40  and separate the contents from the atmosphere, with the help of adapting collar  24  with rolled edge  25 . FIG. 1A illustrates a collar  24  with conforming edge  25  and a riser lip  23  to receive the pasteurizer unit. The collars can be produced in sizes to accommodate any combination of containers and pasteurizer units, using stainless steel. Although gravity alone produces a good seal, optionally a gasket of suitable elastomeric or resilient material (not shown) can be used between the collar and container. Dome top  19  is fabricated of fiberglass or durable plastics as described above for the container, so as to withstand constant scrubbing. 
     Impeller  38  is attached to shaft  36 , which is driven by driving means  17 , conventionally an electrical motor. Various types of propellers having at least two blades and other types of impellers can be used, provided they produce the desired thorough circulation of the treated fluid. Although the impeller is normally rotated to drive the fluid upward past the heating/cooling coil, the motor can be reversed. Multiple impellers and/or shafts can be used if required by the configuration of the product container. The motor should be an industrial grade electrical motor which is suitable for damp environments. Motor  17  is supported by chassis plate  28 , which is sealingly secured into dome top  19  in a watertight manner by screws  29 , washers  22  and nuts  20 , or other suitable fasteners. Chassis plate  28  can be fabricated of aluminum or suitable plastics. Control system  30 , also secured to chassis plate  28 , is discussed below. Water inlets  14  and outlets  15  are also discussed below. Thermocouple  26  preferably reaches to approximately the lower third of the fluid in the container when the unit is assembled, and senses the temperature of the circulating fluid when the system is operating. The positions of the coil, impeller and thermocouple permit operating with a partially full container of product. Coil mounts  32  and screws  34  are used to fasten the two ends of heat exchange coil  42  to chassis plate  28 . The ends of coil  42  provide male attachment sites for tubing to be clamped inside dome top  19 . The components attached to the dome top and chassis plate, including coil  42 , shaft  36  and thermocouple  26 , are attached securely and braced with suitable brackets or shields (not shown) to prevent damage while the unit is being handled. 
     Heating/cooling coil  42 , more easily seen in FIG. 2, extends downward from the dome top via inlet and outlet sections to concentrate the main heat exchange sections near the bottom of the container of fluid to be treated. The lower section of the coil has a helical conical form; that is, as shown in the figures, it describes circles of decreasing diameter from bottom to top, starting with a diameter which is nearly that of the container itself. While any suitable configuration can be used for the coil which optimizes heat transfer between the fluids inside and the fluid to be treated, this helical conical form is considered effective because the impeller drives the fluid to be treated from the bottom of the container past many sections of the coil, whence it circulates throughout the container to achieve rapid and uniform temperature change for the treated fluid. This configuration maximizes surface area exposure of the tubing for heat transfer and cleaning purposes. The impeller illustrated an rotate at about 45 to 60 RPM. Multiple coils can be used in certain configurations of the apparatus, at the expense of greater complexity For example, a faster transition between heating and cooling phases can be made if separate coils are used for heating and cooling fluids, with cooling fluid turned on as heating fluid is shut off. 
     FIG. 3 is a schematic diagram of a control system for the operation of the apparatus and method of an embodiment of the invention. It must be emphasized that a variety of control systems assembled from commercially available controllers, switches, valves and the like can be used for this purpose. The controller uses an off-on-start type switch similar to the ignition switch in a car. The controller monitors and displays the temperature of the circulating liquid and turns the various devices on and off as required. The controller illustrated is microprocessor-based, but analog controllers can also be used. In the most basic version, or perhaps an alternative version, the apparatus can be manually controlled, provided that a thermometer or other appropriate temperature sensor is available. Preferably, the controller comprises a programmable logic controller (PLC), which would allow many other desirable programming options including data logging and interfacing with personal computers Suitable controllers should have thermocouple inputs, plus at least two event-driven contacts which can be set or programmed to energize or deenergize based upon current temperature conditions. Suitable controller components are commercially available from the Barber-Colman Co. of Loves Park, Ill., Honeywell and other sources. 
     As shown in FIG. 3, control system  60  comprises a controller  30  which communicates with solenoid inlet valves relay  68 , heater  70 , display  50 , thermocouple probe  26 , motor  17 , main switch  44 , circulating pump  78 , optional cooler  77  and solenoid outlet valves relay  80 . In operating the system, after placing the dome top on the container (preferably securing same in place) and connecting water hoses and power, main switch  44  is turned on and hot water solenoid inlet valve  57  is opened to allow entry of hot water from source  64 . Heater  70  is normally turned on to heat the hot water to the proper pasteurizing or sterilizing temperature. Heater  70  should be adequate to produce water at pasteurizing or sterilizing temperatures from sources such as ordinary hot water heaters which may be used in dairy barns. Such hot water heaters produce water in the 175 to 200 deg. F. range. If such hot running water is not available, additional or more powerful inline heaters can be used. Alternatively, if a source of steam is available, steam may be injected into the hot water intake system to heat the water, as disclosed in U.S. Pat. No. 3,780,644, which is incorporated herein by reference. 
     Motor  17  is started to rotate the impeller  38  and circulate the fluid to be pasteurized, and pump  78  removes the hot water after it has circulated through coil  42 . Such a pump is preferably used to circulate water within the apparatus, and larger or additional pumps could be installed if normal water pressure is unavailable. However, with water pressure at least that of normal household water systems, it is possible to operate such a system on water pressure alone. Hot water flow continues until the temperature in the circulating fluid under treatment reaches the predetermined temperature (e.g., 161 deg. F. for bovine milk to be pasteurized) and a timer  52  is started to maintain the temperature for a predetermined time (e.g., 30 minutes for normal milk pasteurization at 145 deg. F., or 15 seconds at 161 F.). At this point, heater  70  is shut off, and after the elapsed time hot water solenoid valve  68  is closed. 
     Cold water solenoid valve  68  is then promptly opened, and a flow of cold water maintained until the temperature of the circulating fluid is reduced to the proper level for immediate use (i.e., about 100 deg. F.) or storage (about 38 deg. F.). Naturally, the colder the water the faster the treated liquid can be cooled and the longer the product will last without spoiling. Normal cold tap water is sufficient at moderate ambient temperatures, but for faster cooling and/or chilling to storage temperatures, chilling or refrigeration systems can be used in the cold water intake system, represented by cooler  77  in FIG.  3 . Such systems can be as simple as a chamber containing ice over which the intake water flows, or can incorporate conventional inline refrigeration systems such as used to produce chilled drinking water. U.S. Pat. No. 3,780,644 discloses such systems in columns 4 and 7. Once the liquid is cooled to the desired temperature, all solenoid valves are closed, pump  78  and motor  17  are shut off, and the pasteurized milk (or other heat-treated fluid) can be drawn for use such as feeding calves. 
     As suggested above, such control systems can be assembled and set up for operation on a manual basis, but are preferably capable of fully automatic operation and are programmed to execute the complete cycle as outlined above with a simple actuation by the operator. The objective is to permit the pasteurization or other heat treatment to proceed with a minimum of attention from the operator. Display panel  27  provides visual signals (using LED light-emitting diodes or the like) while the system is operating, identifying the heating and cooling stages, and preferably includes audible signals as well. The operator may be busy with other tasks, but will want to utilize the product promptly when the cycle is complete, and perhaps initiate another cycle with a fresh container of product. 
     FIG. 4 illustrates a typical switch/display panel  27  for the apparatus. Switch  44  is similar to an automotive ignition switch in that it has three positions—power off, power on, and “start,” to initiate a programmed heat treatment cycle. For more basic models or an alternative to the programmed cycle, switching can be provided to initiate the heating and cooling cycles separately (not shown). Digital display  49  displays the temperature measured by thermocouple  26  in the circulating liquid. Signal lights  51  light up for power on and the heating or cooling cycles, as discussed below. At least two buttons  41  are provided for programming heating and cooling temperatures and other functions used in setting up the apparatus for standard cycles. 
     FIG. 5 illustrates the underside of the dome top  19  with the chassis plate removed. Lifting eye  18  is attached by nut  12 , load support  10  and washers  11 . Thermometer module  50  is connected to thermocouple  26  (not shown here) and registers the temperature of the treated fluid on digital display  49 . The thermometer module  50  fits into recess  56  in the dome top. Signal lights  53 ,  54  and  55  are red, amber and yellow respectively, and light up to signal the heating, cooling and power stages of the heating/cooling cycle. These lights can be any suitable type, but are preferably light-emitting diodes (LEDs). Preferably, the light signals also actuate an audible signal (not shown here) to alert the operator to the progress of the cycle. Fastener/sealer  59  secures the back of thermostat  50 , and switch box  61  is attached to switch  44 . Fasteners/connections  63  provide power to signal lights  53 ,  54  and  55 . Double electric solenoid valves  57  and  58  control the inlet and outlet of hot and cold water, and are actuated as described above in the control system, using simple on-off control. The valves are connected to hose fittings (not shown here) on the outside of the dome top, to which ordinary utility hoses can be attached to connect the apparatus to sources of heating and cooling water as shown in FIG.  6 . Hoses  86  connect to the inlet and outlet fittings. An electrical in-line heater  70  is provided within the hot water circuit to bring the heating water to the proper predetermined temperature for the cycle. The heater is actuated as discussed above. Heater  70  and circulating pump  78  can be mounted on chassis plate  28 , as shown in FIG.  7 . FIG. 9 provides a detailed view of a typical inline heater, which is commercially available from Infinity Fluids. As shown, leads  73  provide power to heating element  74 , in response to signals from leads  75 . Other suitable heaters are available commercially from Electro-Pak, Inc. of Reading, Pa. Various types of commercially available gas-powered inline heaters can also be used. 
     FIG. 6, a perspective view of the dome top  19  from another side, reveals hose connections  64  and  66  for hot and cold water inlets, respectively, as well as hot and cold outlets  82  and  84 . Hoses  86  are attached to both inlets and outlets (not shown here). 
     FIG. 7 illustrates the mounting of the controller components  46 ,  52 ,  71 ,  13 ,  71 ,  79  and  47 , plus inline heater  70  and circulating pump  78  on chassis plate  28 , from which motor  17  has been detached. Motor  17  is normally held in place by motor mount bolts  21 . FIG. 8 illustrates these components in detail. Components of controller  30  include multiple relay switches  46 , timer  52  and separate relay switches for the heater ( 71 ), motor ( 13 ) and pump ( 79 ), all mounted on a standard DIN mounting strip  47 . All these components are electrically interconnected to function with the control system  60  described above and in FIG.  3 . Inline heater  70  and pump  78  are mechanically fixed to chassis plate  28  by conventional fasteners (not shown), and electrically connected and plumbed as described above. 
     FIG. 10 illustrates a detergent dispenser  60  for cleanup of the apparatus between cycles. Once the apparatus has finished a pasteurizing cycle, it is raised from the pasteurizing container  40  and returned to a suitable cleaning/storage drum (not shown) where cleaning takes place. The detergent dispenser  60  is plumbed into hot water line  72  so that detergent can be injected into the line. In use, the operator pushes button  67  to dispense a predetermined amount of detergent into vacuum straw  65 . Detergent bottle  62  is removably attached to the top of the dispenser and releases detergent through a valve (not shown) actuated by button  67 . The operator then turns spring timer valve  69  to the “on” position to initiate hot water flow for a set period of time, and hot water with detergent flows into the high pressure cleaning nozzles (not shown), which are mounted on or near the bottom of the cleaning/storage container. The timer is normally set for about ten minutes, five minutes of which the water will carry detergent, followed by a five minute rinse. The nozzle in the bottom of the cleaning/storage container can be a clean-in-place tank nozzle such as the ScrubMate™ by BETE, other clean-in-place sprayers such as those used in dairy bulk tanks, plastic high pressure spray nozzles strategically placed in the drum, or rotating spray arms such as those used in dishwasher manufacture. When the cleaning cycle is complete, the apparatus is allowed to drain and stay stored in the cleaning drum until its next use in pasteurization. The cleaning/storage drum includes at least one drain port in the bottom of the drum to allow cleaning water to escape to floor drains. 
     FIG. 11 illustrates a simple wall mounting bracket assembly  90 , fabricated from a single plate of sheet metal  92 , which allows the apparatus to be elevated and swung from one drum to another, provided they are located side by side. Wall bracket  92  is fastened to the wall securely with bolts or screws (not shown) through holes  94 . A one-piece solid shaft is bent at a right angle to form vertical ( 98 ) and horizontal ( 96 ) sections, and the vertical section hinges within simple tube hinges  100  and  102 . The unit is secured in place with cotter pin  104  or the like. The horizontal portion  96  of the shaft can then be fastened to the lifting eye  18  of the apparatus via eye bolt  108  and conventional hoisting apparatus (not shown). Once the apparatus is elevated and thus attached, it can be swung clear of the first container and placed over another alongside. 
     EXAMPLE 
     The operation and value of the apparatus and methods of the invention will be further illustrated by the following non-limiting example. A prototype pasteurizer of the invention was used in a dairy operation for about six months to pasteurize waste milk for consumption by a group of Holstein and Jersey calves. An average of about 45 calves were being fed the product at any given time over this period. Health problems in the calves, along with labor and medical expenses, were significantly reduced (by about 90 percent overall) during this period. New cases of scours (diarrhea) and related illnesses such as joint ill, septicemia, pneumonia, etc. were reduced about 90 percent, with concurrent reductions in labor and medical costs. Significant increases were noted in weight gain, and immediate savings were realized by the elimination of the need to supplement the calves&#39; feed with expensive milk replacer. It is anticipated that even greater improvements will be seen over the next two years as the results of the decrease in pathogens spread will become apparent when these calves grow into replacement cows and come into milk. The operators of the herd are very pleased with the initial results. 
     Clearly, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described herein.