JPH10165153A - Steam type stertlizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal sterilizer with steam capable of uniformizing the temperature distribution in a sterilizing chamber even in a cooling step and taking out the resultant product in a state of a dried surface thereof. SOLUTION: This steam type sterilizer is obtained by installing a partition plate 4 in a sterilizing vessel 1, dividing the sterilizing vessel 1 into a sterilizing chamber 2 and a circuit 3 and enabling the production of a circulating stream of a gas with a blower 5. The sterilizer is capable of spraying cooling water from spray nozzles 9 provided in jetting pipes 6 into the circuit 3, cooling the circulating gas therewith and cooling the resultant product with the low- temperature gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a retort pouch,
The present invention relates to a steam sterilizer for sterilizing packaged food such as cups, bottles, and cans with high-temperature and high-pressure steam.

[0002]

2. Description of the Related Art In a conventional steam sterilizer, a steam pipe, a compressed air pipe, and a cooling water pipe are connected to a sterilization tank, and a sterilization process is performed by circulating a mixed gas of steam and air with an ejector and a blower during a sterilization process. The temperature inside the tank is made uniform. However, during the cooling step, the gas cannot be circulated sufficiently due to limitations in the mechanism, causing temperature unevenness. Further, cooling water is directly sprayed onto the object to be treated, and the object (product) after the sterilization is taken out with the attached water remaining on the surface.

[0003]

As described above, in the conventional steam sterilizer, the temperature in the sterilization tank is uniform during heating, but there is a problem that a temperature difference occurs during cooling. . Further, since the product to be taken out after the sterilization is put on a label or packed in a box, it is necessary to remove adhered water remaining on the surface by a method such as drying or wiping. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a steam-type sterilizing apparatus in which the temperature distribution in the sterilizing chamber becomes uniform even during cooling, and the product surface can be taken out in a dry state. Things.

[0004]

Means for Solving the Problems In order to achieve the above object, according to the first invention, a horizontal sterilizing apparatus having an opening / closing lid, a partition plate for dividing a sterilizing tank into a sterilizing chamber and a gas circulation path, A steam sterilizer comprising: a blower installed at an upper opening to forcibly circulate gas; and an ejection pipe provided to cool the gas in the circulation path. Further, in the second invention, a variable speed device is attached to the rotation drive unit of the blower. According to a third aspect of the present invention, there is provided a steam sterilization apparatus in which a plurality of spray nozzles are provided in an ejection pipe provided in a circulation path, and in a cooling step, refrigerant is ejected from the spray nozzles to cool circulating gas. In the fourth invention, the partition plate is formed in a U-shape close to the uppermost surface and both side surfaces of the tray loaded in the sterilization chamber, and the upper surface is provided with an opening for suction of a blower, Steam sterilizer with gas-liquid separator installed at open position.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION

1. In order to equalize the temperature and air flow at all positions of the trays stacked and loaded in the sterilization chamber, a partition plate is provided near the tray to divide the sterilization tank into a sterilization chamber and a circulation path,
The gas in the sterilizing tank can be forcedly circulated between the sterilizing chamber and the circulation path via a blower. The mounting position of the blower is not limited to the upper part of the sterilizing tank shown in the drawing, but may be provided at the rear of the sterilizing tank (the position of the partition plate also changes). 2. The circulating gas passing through the sterilization chamber has a wind speed of 1-2 m / s
Thus, the temperature distribution in the tray becomes uniform, but at the time of the cooling step, the cooling capacity is improved by setting the air velocity to 3 m / s or more per second, thereby enabling cooling in a short time. Therefore, an inverter or a pole number converter is attached to the rotation drive unit of the blower so that the number of rotations of the fan can be changed so that the wind speed in the cooling step can be increased. 3. In order to cool the circulating gas, an ejection pipe equipped with a spray nozzle capable of spraying a refrigerant is installed in the circulation path. As the refrigerant, cold water, liquid nitrogen, carbon dioxide, or the like is used. 4. When cold water is used for cooling, mist-like water droplets may be generated in the gas. A gas separation device such as an eliminator is installed below the lowermost tray, and the gas from which the water droplets have been removed is circulated in the sterilization chamber. Let it.

[0006]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing the entirety of the apparatus of the present invention, and FIG. 2 is a vertical sectional view of the apparatus of the present invention. In this figure, a cylindrical horizontal type is used, but the shape is not limited and may be a square type. Reference numeral 2 denotes a sterilization chamber, in which the object to be processed is sterilized. A circulation path 3 is a gas passage which allows a mixed gas of steam and air or air to circulate in the sterilization tank in order to make the temperature in the sterilization chamber 2 uniform. 4
Is formed in a U-shape by a partition plate, is provided over substantially the entire length of the sterilization tank 1, and divides the inside of the sterilization tank 1 into a sterilization chamber 2 and a circulation path 3. Reference numeral 5 denotes a blower, which is installed above the sterilizing tank 1, and whose rotating shaft is sealed with a mechanical seal (not shown) so that the drive unit 27 can be shifted by an inverter or the like. Reference numeral 6 denotes an ejection pipe provided in the circulation path 3 on both sides and connected to pipes for steam, cooling water, and compressed air. Reference numeral 7 denotes a tray, which is provided with an object to be processed and loaded into the sterilization chamber 2. Reference numeral 8 denotes a gas-liquid separation device which is mainly composed of a perforated plate and a wire mesh, which removes water droplets contained in the gas and uniformly disperses the gas flow. Reference numeral 9 denotes a spray nozzle attached to the ejection pipe 6. Reference numeral 10 denotes a suction port of the blower 5 provided on the upper surface of the partition plate 4. The sterilization tank 1 is connected with a steam pipe 11, a cooling water pipe 12, a compressed air pipe 13, a drain pipe 14, and an exhaust pipe 15. The steam pipe 11 is provided with a steam valve 16, a temperature control valve 17, and a throttle control valve 18, and has one end connected to the ejection pipe 6 installed in the circulation path 3. Cooling water piping 12
Is provided with a cooling water valve 19, one end of which is connected to the ejection pipe 6. The compressed air pipe 13 is provided with an air valve 20, a pressure regulating valve 21, and a throttle regulating valve 18.
Connected to a bent pipe 22 provided therein. The bent pipe 22 is a heat exchange section provided so that it can be heated when the compressed air flows into the sterilization tank, and the other end is connected to the ejection pipe 6. The drain pipe 14 is provided with a drain valve 23, a trap valve 24, and a steam trap 25.
Connected to the bottom of One end of the exhaust pipe 15 is connected to the upper part of the sterilization tank 1 and the other end is connected to an exhaust valve 26. In this embodiment configured as described above,
The sterilization process of the retort pouch will be described in order. (1) Deaeration Step By opening the steam valve 16, the temperature control valve 17, the drain valve 23, the trap valve 24, and the exhaust valve 26 and closing the other valves, the steam circulates from the spray nozzle 9 through the ejection pipe 6. It is supplied into the road 3. At the same time, the air in the sterilization tank 1 is exhausted from the drain pipe 14 and the exhaust pipe 15 to the outside. At this time, by operating the blower 5, the air in the sterilization chamber 2 is promptly replaced with steam, and the object to be treated is preheated. (2) Temperature raising step The steam valve 16, the temperature control valve 17, the pressure control valve 21, and the trap valve 24 are opened, and the exhaust valve 26 is controlled based on a signal from a pressure sensor (not shown) provided in the sterilization tank 1. To open and close. By closing all other valves, the pressure inside the sterilization tank 1 becomes the set pressure of the pressure sensor, and by operating the blower 5, a mixed gas of steam and air generates a circulating flow as shown by an arrow in the figure. The temperature in the sterilization tank 1 becomes uniform. Further, the temperature is raised to a set temperature of a temperature sensor (not shown). (3) Sterilization Step The pressure regulating valve 21 and the trap 24 are opened. The temperature control valve 17 opens and closes based on a detection signal of a temperature sensor in the sterilization chamber 2. The exhaust valve 26 also opens and closes based on a signal from the pressure sensor, as in the temperature raising step. All other valves are closed. By operating the blower 5, the temperature in the sterilization tank 1 is made uniform, and the heat transfer of heating of the processing object is promoted. (4) Cooling Step At the start of the cooling step, the cooling water valve 19 opens and closes at intervals of several seconds by setting a timer, and then opens. The cooling water sprayed from the spray nozzle 9 directly cools the mixed gas, wets the wall surface in the circulation path 3, and cools the gas also from the heat transfer by the wall surface. When the gas thus cooled passes through the gas-liquid separation device 8, water droplets in the gas are removed, and the gas to be processed can be cooled without getting wet. In this process, the blower 5
Is operated at high speed to equalize the temperature in the sterilization chamber and increase the wind speed on the surface of the object to be treated to enhance the cooling effect. Although not shown, a pump and a heat exchanger can be provided in the cooling water line to circulate the cooling water.

[0007]

According to the present invention, the first configuration having the above configuration is provided.
In the present invention, by providing the partition plate and the blower in the sterilizing tank, the forced circulation of gas can be generated, and the temperature distribution in the sterilizing chamber can be made uniform. In the second aspect of the invention, by changing the rotation speed of the blower, the temperature distribution can be made more uniform and the cooling effect can be enhanced, particularly during the cooling step. In the third aspect of the present invention, the gas is cooled in the circulation path, and the object to be processed is cooled by the low-temperature gas, so that a dried product in which water droplets do not adhere to the surface of the object to be processed can be obtained. Further, since the refrigerant is not directly applied to the object to be treated, there is no abrupt change in the bag in which the product is packaged, and no stain due to water scale is generated. According to the fourth aspect of the present invention, in the sterilization chamber surrounded by the partition plate, the gas removed by the effect of the gas-liquid separator is rectified and flows in from below, so that an upward gas flow having a blower inlet is generated. Uniform sterilization without uneven temperature is obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view and a flowchart showing the entirety of the apparatus of the present invention.

FIG. 2 is a longitudinal sectional view of the device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sterilization tank 6 Spout pipe 2 Sterilization room 7 Tray 3 Circulation path 8 Gas-liquid separation device 4 Partition plate 9 Spray nozzle 5 Blower 10 Suction port

Claims (4)

[Claims] 1. A sterilizing tank having a horizontal opening / closing lid, a partition plate for dividing the sterilizing tank into a sterilizing chamber and a gas circulation path, a blower installed at an opening of the partition plate to forcibly circulate gas, and a circulation device. A steam-type sterilizing apparatus, comprising: a jet pipe provided to cool gas in a road. 2. The steam sterilizer according to claim 1, wherein a variable speed device is attached to the rotary drive of the blower. 3. A spray pipe provided in a circulation path is provided with a plurality of spray nozzles, and in a cooling step, refrigerant is blown from the spray nozzles to cool a circulating gas. Steam sterilizer. 4. A partition plate is formed in a U-shape adjacent to the uppermost surface and both side surfaces of the tray loaded in the sterilizing chamber, and an opening for suction of a blower is provided on the upper surface. The steam-type sterilizer according to claim 1, wherein a gas-liquid separator is installed at the open position.