JP6036274B2 - Sterilizer - Google Patents

Description

  The present invention relates to a sterilizer used for heat sterilization and subsequent cooling of retort foods and the like.

  A sterilization apparatus is known in which an object to be processed is accommodated in a treatment tank, sterilized by heating with steam or hot water, and then cooled with cooling water. In this type of sterilizer, cooling water is supplied into the treatment tank filled with steam at the start of the cooling process after the sterilization process.

  However, when cooling water is supplied into the treatment tank filled with steam, the steam in the treatment tank is condensed, and the pressure in the treatment tank is rapidly reduced. Even if the pressurized air is introduced into the treatment tank so as to compensate for the pressure drop due to vapor condensation, the introduction of the pressurized air may not catch up, and the pressure in the treatment tank may drop rapidly. In that case, there is a possibility of causing damage to the object to be processed (for example, bag breakage of the retort pouch).

  Therefore, as disclosed in Patent Document 1 below, in a sterilizer that heats and sterilizes an object to be processed with 100% steam without pressurizing the inside of the processing tank with air, cooling water is stored in advance in the lower part of the processing tank. In addition, during the sterilization process, it is proposed that the object to be treated is heated by steam and the stored cooling water is also heated to the sterilization temperature. In this case, in the cooling step, the heated cooling water is sprinkled into the object to be treated, and the cooling water is gradually introduced into the treatment tank, and the temperature of the cooling water is gradually lowered, thereby Cooling is achieved.

  In addition, as disclosed in Patent Document 2 below, after sterilizing the object to be treated with steam, hot water is made by introducing cooling water into the treatment tank and heating it (hot water preparation step), In the cooling step of injecting hot water onto the object to be processed, it has been proposed to cool the object to be processed while repeating a short time injection of 1 second or less and an injection pause longer than that. In this case, the cooling water is not supplied into the treatment tank while the short-time injection of the cooling water and the injection pause are repeated (FIG. 2 of Patent Document 2). Then, when cooling of a to-be-processed object progresses, the temperature of cooling water is reduced by supplying cooling water in a processing tank, and further cooling of a to-be-processed object is achieved.

Japanese Patent Publication No. 7-95935 (Claim 1, page 2, right column, line 38-page 3, left column, line 1, FIG. 1) Japanese Patent Laying-Open No. 2010-94051 (Claim 1, paragraphs 0009-0013, FIGS. 1 to 3)

  However, in the case of the invention described in Patent Document 1, it is necessary to store cooling water in the treatment tank in advance in order to sterilize with 100% steam, and since the stored water is not circulated, temperature unevenness is likely to occur. In the subsequent cooling step, it is not preferable.

  In the case of the invention described in Patent Document 1, after sterilization is performed with 100% steam, the feed water flow rate into the treatment tank in the cooling process is constant. For this reason, immediately after the start of the cooling step, the condensation of the vapor in the treatment tank is large, and the pressure in the treatment tank may rapidly decrease. Alternatively, if the feed water flow rate is decreased in order to prevent this, the subsequent cooling process will take time.

  On the other hand, in the case of the invention described in Patent Document 2, there is no inconvenience since the cooling water is not newly supplied into the processing tank while repeating the short-time injection and the suspension of the cooling water. When the cooling water is started to be supplied to the water, the water supply flow rate is constant, so that the same inconvenience as the invention described in Patent Document 1 occurs. In the first place, in the case of the invention described in Patent Document 2, after sterilizing with steam without storing water in the treatment tank, the cooling water is suddenly supplied into the treatment tank in the warm water preparation step, and the water supply flow rate is constant. Therefore, a rapid decrease in pressure due to vapor condensation in the treatment tank is inevitable.

  In addition, in Patent Document 2, there is a description that the sterilization process can be performed with hot water, but until the sterilization with hot water, the warm water preparation process and the cooling process (short-time injection of cooling water and (Repetition with injection stop) is not performed in the same manner. In the first place, if there is hot water in the treatment tank in the sterilization process, it is unclear how to perform the subsequent warm water preparation process.

  Furthermore, in any invention described in any of the patent documents, in the cooling step after the sterilization step, the cooling water is supplied into the treatment tank to gradually lower the temperature of the cooling water, but only the cooling water is supplied into the treatment tank. Then, there is a possibility that the object to be processed flows in the cooling water in the course of time.

  The problem to be solved by the present invention is to provide a sterilizer capable of preventing a sudden decrease in pressure in a treatment tank in a cooling process and protecting a workpiece.

The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is a sterilization method in which hot water is jetted toward an object to be processed accommodated in a processing tank to heat the object to be processed. A sterilization apparatus that performs a cooling step of cooling the workpiece by introducing cooling water into the treatment tank after the process, and is capable of supplying water into the treatment tank in which the workpiece is accommodated. And the water supply means which can change the water supply flow rate, the drainage means from the inside of the processing tank, the pressurizing means for introducing pressurized air into the processing tank, the exhaust means from the inside of the processing tank, A circulation means for returning water stored in the treatment tank by the water supply means to a water level that does not submerge an object from the bottom of the treatment tank to an object to be treated in the treatment tank; and by the circulation means in a sterilization step Heating means for heating the circulating water, sterilization process and cooling In the process, the pressurizing means and the exhaust means are controlled so that the inside of the treatment tank is maintained at a pressure higher than the saturated vapor pressure corresponding to the temperature in the treatment tank. The flow rate can be adjusted in two stages with a large flow rate water supply with a lot of water, and in the cooling process, water is supplied by the water supply means to the upper limit water level in the treatment tank while circulating the water in the treatment tank by the circulation means. The draining means repeats draining for a predetermined time, and before the set time elapses after the start of the cooling process, the water supply means feeds water into the treatment tank by a small flow rate water supply, while the set time elapses. It is a sterilizer characterized by performing by water supply .

  According to the first aspect of the present invention, the amount of cooling water introduced into the treatment tank in the cooling step is suppressed before the set condition is satisfied than after the set condition is satisfied. Until the setting condition is satisfied, the amount of steam condensed immediately after the start of the cooling step can be suppressed by suppressing the amount of cooling water introduced into the treatment tank. Thereby, it is possible to prevent a sudden decrease in the pressure in the processing tank and prevent the object to be processed from being damaged.

According to the first aspect of the present invention, in the sterilization step, the water stored at the bottom in the treatment tank is circulated by returning the water to the object to be treated by the circulation means, and the circulating water is heated by the heating means. To do. Thereafter, the hot water is used as cooling water in the cooling step, and the workpiece is cooled by gradually replacing the water in the cooling step to lower the water temperature. By starting to use the hot water in the sterilization process as it is as the cooling water in the cooling process, it is possible to reduce the temperature difference during the process transition and to prevent rapid condensation of the steam in the treatment tank. Also, in the cooling process, instead of simply adding cooling water into the treatment tank, the water in the treatment tank is gradually drained and the water in the treatment tank is gradually replaced. Can be gradually reduced. Furthermore, the rapid condensation of the vapor | steam in a processing tank can be prevented by reducing the feed water flow rate in the processing tank immediately after a cooling process start. In this way, by reducing the pressure drop rate in the treatment tank, the introduction of pressurized air into the treatment tank is not delayed, the inside of the treatment tank can be maintained at a desired pressure, Damage to the object can be prevented.

According to invention of Claim 1 , the water in a processing tank can be replaced gradually easily by repeating the water supply to an upper limit water level, and the waste_water | drain for predetermined time . In addition, after starting the cooling process and before the set time has elapsed, water supply to the treatment tank is performed at a small flow rate to prevent rapid condensation of the steam in the treatment tank and prevent a rapid decrease in the pressure in the treatment tank. can do.

  ADVANTAGE OF THE INVENTION According to this invention, the sudden fall of the pressure in the processing tank in a cooling process can be prevented, and a to-be-processed object can be aimed at.

It is the schematic which shows one Example of the sterilizer of this invention.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view showing an embodiment of the sterilizing apparatus 1 of the present invention, and a part thereof is shown in cross section. The sterilization apparatus 1 of the present embodiment is an apparatus that cools the workpiece 2 after heat sterilization. The workpiece 2 is not particularly limited, but is typically a retort food.

  The sterilization apparatus 1 of the present embodiment includes a treatment tank 3 in which an object to be treated 2 is accommodated, a water supply means 4 into the treatment tank 3, a drainage means 5 from the treatment tank 3, and a treatment tank 3. Pressurizing means 6 for introducing pressurized air, exhaust means 7 from inside the processing tank 3, circulating means 8 for stored water in the processing tank 3, heating means 9 for heating the circulating water, and each of these means And control means (not shown) for controlling 4-9.

  The treatment tank 3 is a hollow container that accommodates the workpiece 2. The shape of the treatment tank 3 is not particularly limited. In the present embodiment, the treatment tank 3 includes a horizontally disposed cylindrical material, and this cylindrical material has one opening closed and the other opening opened and closed by a door. It is possible. Therefore, the workpiece 2 can be taken in and out of the processing tank 3 by opening the door, and the opening of the processing tank 3 can be airtightly closed by closing the door.

  The processing tank 3 is provided with a temperature sensor 10 that detects the temperature in the processing tank 3 and a water level detector (not shown) that detects the water level in the processing tank 3.

  In the case of the illustrated example, the objects to be processed 2 are arranged in a tray 11, and such trays 11 are stacked in the vertical direction and accommodated in the processing tank 3. The tray 11 is a shallow rectangular container that opens upward, and a large number of openings are formed at least on the bottom surface. The upper and lower trays 11 are stacked with gaps on the side surfaces. However, the to-be-processed object 2 may be accommodated in the processing tank 3 by mounting on the shelf in the processing tank 3, or mounting on a wagon.

  The water supply means 4 supplies water into the treatment tank 3 through the water supply path 12. The water supply means 4 is configured to be able to change the water supply flow rate into the treatment tank 3. In this embodiment, the water supply path 12 is bifurcated on the downstream side (processing tank 3 side) from the water supply pump 13, and then merges again and is connected to the processing tank 3. Thereby, a part of the water supply path 12 is configured by arranging the first water supply path 12a and the second water supply path 12b in parallel.

  A first water supply valve 14 is provided in the first water supply path 12a, and a second water supply valve 15 is provided in the second water supply path 12b. In a state where the water supply pump 13 is operated, one or both of the water supply valves 14 and 15 are opened to supply water from the water supply source into the treatment tank 3. At this time, the water supply flow rate into the treatment tank 3 can be adjusted in two stages by opening either the first water supply valve 14 or the second water supply valve 15, or by opening only one or both. It is said that.

  Specifically, the water supply means 4 of the present embodiment is capable of changing the water supply flow rate in two stages of a small flow rate water supply and a large flow rate water supply with a higher flow rate, and the second water supply valve 15 is closed. If only the first water supply valve 14 is opened, water can be supplied into the treatment tank 3 with a small flow rate water supply, and if only the second water supply valve 15 is opened with the first water supply valve 14 closed, the water can be supplied into the treatment tank 3 with a large flow rate water supply. However, the large flow rate water supply into the treatment tank 3 does not open only the second water supply valve 15 with the first water supply valve 14 closed, but both the first water supply valve 14 and the second water supply valve 15. It may be done by opening. On the other hand, if both the 1st water supply valve 14 and the 2nd water supply valve 15 are closed, the water supply to the processing tank 3 can be stopped.

  Although details will be described later, with the start of operation of the sterilizer 1, water is supplied into the treatment tank 3 by the water supply means 4, and water is stored up to the set water level. The set water level is a water level that does not submerge any object 2 in the treatment tank 3. Specifically, even if the set water level is determined below the workpiece 2 disposed at the lowermost part in the treatment tank 3 and water is stored up to the set water level, any of the treatment objects in the treatment tank 3 is stored. 2 is not immersed in the stored water.

  The drainage means 5 drains the water from the treatment tank 3 through the drainage channel 16. The drainage channel 16 is connected to the bottom of the treatment tank 3 and is provided with a drainage valve 17. By opening the drain valve 17, the water in the processing tank 3 can be discharged to the outside.

  The pressurizing means 6 supplies pressurized air (in other words, compressed air) into the processing tank 3 through the pressurizing passage 18. By opening the pressurizing valve 19 provided in the pressurizing passage 18, pressurized air from a pressurized air source can be supplied into the processing tank 3, and the inside of the processing tank 3 can be pressurized to a pressure exceeding the atmospheric pressure. .

  The exhaust means 7 exhausts the gas from the inside of the processing tank 3 under a pressure exceeding the atmospheric pressure through the exhaust path 20. The exhaust path 20 is connected to the upper part of the processing tank 3, and an exhaust valve 21 and a check valve 22 are provided in order from the processing tank 3 side. When the exhaust valve 21 is opened in a state where the inside of the processing tank 3 is at a pressure exceeding the atmospheric pressure, the gas in the processing tank 3 is discharged to the outside through the exhaust path 20, and the pressure in the processing tank 3 may be lowered. it can.

  The circulation means 8 draws out the stored water in the treatment tank 3 from the bottom of the treatment tank 3 and ejects the stored water in the treatment tank 3 through the circulation path 23 to return to the object 2 in the treatment tank 3. Circulate water. A circulation pump 24 is provided in the circulation path 23, and the water in the treatment tank 3 can be circulated by operating the circulation pump 24. When the water from the circulation path 23 is returned into the treatment tank 3, it is ejected and returned to the workpiece 2 by the nozzle 25. The nozzle 25 is provided on the side and / or upper part in the processing tank 3. In the case of the illustrated example, the water supply channel 12 and the circulation channel 23 are a common pipeline on the bottom side of the treatment tank 3.

  The heating means 9 heats the circulating water from the circulation means 8. The heating means 9 is not particularly limited in its configuration, but in this embodiment, it is a means for supplying steam to the circulating water. Specifically, in this embodiment, a steam supply path 26 is connected to the circulation path 23 downstream of the circulation pump 24, and the connection between the circulation path 23 and the steam supply path 26 is connected to the circulating water. A steam mixer 27 is provided. The steam supply passage 26 is provided with a steam supply valve 28. Therefore, by opening the steam supply valve 28, steam can be blown into the circulating water in the circulation path 23 to heat the circulating water. By adjusting the opening degree of the steam supply valve 28 based on the temperature detected by the temperature sensor 10 provided in the processing tank 3, the temperature in the processing tank 3 can be adjusted as desired.

  The control means is a controller (not shown) that controls each of the means 4 to 9 based on the detection signal of the temperature sensor 10 and the water level detector, the elapsed time, and the like. Specifically, in addition to the water supply pump 13, the first water supply valve 14, the second water supply valve 15, the drain valve 17, the pressurizing valve 19, the exhaust valve 21, the circulation pump 24, the steam supply valve 28, the temperature sensor 10 and the water level detection. The device is connected to the controller.

  As will be described below, the controller performs heat sterilization of the workpiece 2 in the processing tank 3 and subsequent cooling in accordance with a predetermined procedure (program). Typically, a water supply process, a transition process, a sterilization process, a cooling process, and a drainage process are sequentially performed. Hereinafter, each step will be described. Prior to the operation of the sterilizer 1, the workpiece 2 is accommodated in the treatment tank 3, and the door of the treatment tank 3 is closed. In this state, the exhaust valve 21 is opened, the other valves are closed, and each pump is stopped.

(1) Water supply step In the water supply step, water is supplied into the treatment tank 3 by the water supply means 4 to a set water level at which the workpiece 2 in the treatment tank 3 is not immersed, and the water is stored in the treatment tank 3. At this time, water can be supplied into the treatment tank 3 with a large flow rate of water supply. Specifically, when the water supply pump 13 is operated, only the second water supply valve 15 of the first water supply valve 14 and the second water supply valve 15 is opened, or both the water supply valves 14 and 15 are opened. Good. At this time, the drain valve 17 and the pressurizing valve 19 are closed, and the exhaust valve 21 is opened. When the water level detector detects that water has been stored in the treatment tank 3 up to the set water level, the water supply valve 15 (, 14) is closed and the water supply pump 13 is stopped to end the water supply process.

(2) Transition Step In the transition step, the circulating water is heated by the heating means 9 while circulating the water in the treatment tank 3 by the circulation means 8, and the temperature in the treatment tank 3 is set to the sterilization temperature (for example, 120 ° C.). Raise to. Specifically, the water in the processing tank 3 is circulated by returning the water from the inner bottom of the processing tank 3 into the processing tank 3 through the circulation path 23 by operating the circulation pump 24. Further, the steam supply valve 28 is opened, and steam is blown into the circulating water in the mixer 27 to heat the circulating water.

  Thus, although the temperature in the processing tank 3 is raised gradually, the to-be-processed object 2 expand | swells by heating, and there exists a possibility that packaging (a retort pouch etc.) may burst. Therefore, in order to prevent this, the inside of the processing tank 3 is gradually pressurized by the pressurizing means 6 to a pressure exceeding the atmospheric pressure (slightly higher than the saturated vapor pressure corresponding to the temperature in the processing tank). Specifically, the pressurization according to the temperature in the processing tank 3 is performed by controlling the pressurization valve 19 and the exhaust valve 21. Thereafter, the water circulation by the circulation means 8 and the pressurization in the treatment tank 3 by the pressure means 6 are continued until the end of the cooling step.

(3) Sterilization process In a sterilization process, the temperature in the processing tank 3 is hold | maintained at the sterilization temperature, and the to-be-processed object 2 is heated and sterilized. Specifically, the degree of opening of the steam supply valve 28 is adjusted so as to maintain the temperature detected by the temperature sensor 10 at the sterilization temperature while circulating the water in the treatment tank 3 by the circulation pump 24. When the inside of the treatment tank 3 is at or above the sterilization temperature and the sterilization time has elapsed, the steam supply valve 28 is closed, heating of the circulating water is stopped, and the sterilization process is terminated.

(4) Cooling step In the cooling step, the water in the treatment tank 3 is circulated by the circulation means 8 and the water in the treatment tank 3 is gradually replaced by the water supply means 4 and the drainage means 5 to thereby adjust the temperature of the circulating water. By gradually lowering the temperature, the object 2 in the treatment tank 3 is cooled. Specifically, the water in the treatment tank 3 is gradually replaced as follows in a state where the circulation pump 24 is operated to circulate the water in the treatment tank 3.

  That is, in the cooling step, water is supplied into the treatment tank 3 by the water supply means 4 up to the upper limit water level, while the water is discharged by the drainage means 5 to a lower limit water level lower than the upper limit water level. Thereby, the relatively high temperature water in the treatment tank 3 is gradually replaced with the relatively low temperature water newly supplied into the treatment tank 3 by the water supply means 4, and the water temperature in the treatment tank 3 is lowered. Figured. The upper limit water level and the lower limit water level are detected by a water level detector, and even at the upper limit water level, the lowermost workpiece 2 in the treatment tank 3 is not immersed in the stored water. Moreover, either an upper limit water level or a lower limit water level can be made to correspond with the said setting water level in the said water supply process.

  By the way, immediately after the start of the cooling process, the treatment tank 3 is filled with steam by the immediately preceding sterilization process. In this state, when relatively low-temperature (typically normal temperature) cooling water is supplied into the treatment tank 3 by the water supply means 4, the pressure in the treatment tank 3 rapidly decreases due to the condensation of steam, and the object to be treated. 2 damage (retort pouch bag breakage) may occur. Although control is performed to introduce pressurized air so as to compensate for a pressure drop, the steam is often condensed immediately after the start of the cooling process, and the supply of pressurized air into the treatment tank 3 cannot catch up. There is a fear.

  Therefore, in this embodiment, the water supply to the treatment tank 3 by the water supply means 4 is performed with a small flow rate water supply before the set time elapses after the start of the cooling process, and with a large flow rate water supply after the set time elapses. Specifically, when supplying water into the treatment tank 3, before the set time elapses after the start of the cooling process, only the first water supply valve 14 and the first water supply valve 14 are opened and compared. After the set time has elapsed, only the second water supply valve 15 is opened, or both water supply valves 14 and 15 are opened to supply water at a relatively large flow rate.

  Thereby, condensation of the vapor | steam in the processing tank 3 immediately after a cooling process start can be suppressed, and it can prevent that introduction of pressurized air into the processing tank 3 is delayed. Therefore, the inside of the processing tank 3 can be maintained at a desired pressure to prevent the workpiece 2 from being damaged. When the set time elapses after the start of the cooling process, the steam in the treatment tank 3 is replaced with air by the pressurizing means 6, and thereafter the pressure in the treatment tank 3 is maintained even if water is supplied by a large flow rate water supply. There is no reduction.

  When a predetermined time elapses from the start of the cooling process, or when a predetermined time elapses after the temperature in the treatment tank 3 (or the temperature of the cooling water) falls below the predetermined temperature, the circulation by the circulation means 8 and the water supply by the water supply means 4 are stopped. Then, the cooling process is completed.

(5) Drainage process In the drainage process, the drainage means 5 drains water from the treatment tank 3. Specifically, water is discharged to the outside by opening the drain valve 17. If the drainage means 5 drains while the inside of the treatment tank 3 is pressurized by the pressurizing means 6, drainage from the treatment tank 3 can be performed quickly. Thereafter, the pressurizing valve 19 is closed, the exhaust valve 21 is opened, the inside of the processing tank 3 is returned to atmospheric pressure, the door of the processing tank 3 is opened, and the workpiece 2 is taken out from the processing tank 3. it can.

  According to the sterilization apparatus 1 of the present embodiment, the hot water used in the sterilization process starts to be used as cooling water in the cooling process as it is. Thereby, the temperature difference at the time of a process transfer can be reduced, and the rapid condensation of the vapor | steam in the processing tank 3 can be prevented. Moreover, in the cooling process, the water in the treatment tank 3 is gradually replaced with new water by the water supply means 4, but the water supply flow rate into the treatment tank 3 is suppressed until a set time has elapsed after the start of the cooling process. Thus, it is possible to prevent the water temperature in the processing tank 3 from rapidly decreasing and to prevent the steam in the processing tank 3 from condensing rapidly. In this way, by reducing the pressure drop rate in the processing tank 3, the introduction of pressurized air into the processing tank 3 is not delayed, and the inside of the processing tank 3 can be maintained at a desired pressure. Further, it is possible to prevent the workpiece 2 from being damaged.

  The sterilization apparatus 1 of the present invention is not limited to the configuration of the above embodiment, and can be changed as appropriate. In particular, in the sterilization apparatus 1 that cools the workpiece 2 after heat sterilization, if the amount of cooling water introduced into the treatment tank 3 is suppressed after that until the set condition is satisfied after the start of the cooling process, Other configurations can be changed as appropriate. For example, in the said Example, although the to-be-processed object 2 was heat-sterilized with hot water, you may heat-sterilize the to-be-processed object 2 with a vapor | steam.

  Moreover, in the said Example, although the feed water flow rate into the processing tank 3 was changed before and after the set time passed from the start of a cooling process, the timing which changes a feed water flow rate can be changed suitably. For example, water may be supplied at a small flow rate until the temperature in the processing tank 3 or the temperature of the cooling water in the processing tank 3 falls to a set temperature.

  Moreover, in the said Example, although the feed water flow rate was switched in two steps, a small flow rate feed water and a large flow rate feed water, it may be switched in three steps or more, and it is continuously changed to gradually increase the feed water flow rate. May be. For example, the feed water flow rate into the treatment tank 3 may be gradually increased by inverter-controlling the feed water pump 13 or gradually opening the opening of the feed water valve 14 (15). In this case, it is not necessary to provide the first water supply path 12a and the second water supply path 12b in parallel, and only one of them is sufficient.

  Moreover, in the said Example, although the heating means 9 injected the vapor | steam into the circulating water in the circulation path 23, you may inject a vapor | steam into the stored water in the bottom part of the processing tank 3. FIG. Alternatively, a heat exchanger may be provided in the circulation path 23, and the circulating water may be indirectly heated with steam in the heat exchanger.

  Furthermore, in the said Example, in the cooling process, by repeating the water supply to the upper limit water level and the drainage to the lower limit water level, the water in the treatment tank 3 was gradually replaced to lower the water temperature. After the water supply up to, it may be repeatedly drained for a predetermined time. Or you may control so that the amount of drainage by the drainage means 5 may be adjusted so that a target water level may be maintained in the state which continued the water supply in the processing tank 3. FIG. At this time, not only the amount of drainage by the drainage means 5 but also the amount of water supply by the water supply means 4 may be controlled so as to maintain the target water level.

DESCRIPTION OF SYMBOLS 1 Sterilization apparatus 2 To-be-processed object 3 Processing tank 4 Water supply means 5 Drainage means 6 Pressurization means 7 Exhaust means 8 Circulation means 9 Heating means 10 Temperature sensor 11 Tray 12 Water supply path 12a First water supply path 12b Second water supply path 13 Water supply pump DESCRIPTION OF SYMBOLS 14 1st water supply valve 15 2nd water supply valve 16 Drainage path 17 Drainage valve 18 Pressurization path 19 Pressurization valve 20 Exhaust path 21 Exhaust valve 22 Check valve 23 Circulation path 24 Circulation pump 25 Nozzle 26 Steam supply path 27 Mixer 28 Supply Steam valve

Claims (1)

The sterilization which performs the cooling process which introduce | transduces cooling water into the said processing tank and cools a to-be-processed object after the sterilization process which spouts hot water toward the to-be-processed object accommodated in the processing tank, and heats a to-be-processed object A device ,
The treatment tank in which the object to be treated is accommodated;
Water supply means capable of supplying water into the treatment tank and capable of changing the water supply flow rate;
Means for draining from the treatment tank;
Pressurizing means for introducing pressurized air into the treatment tank;
Means for exhausting from the treatment tank;
Circulating means for returning the water stored in the treatment tank by the water supply means to a water level that does not submerge the treatment object from the bottom of the treatment tank and returning it to the treatment object in the treatment tank;
Heating means for heating the circulating water by the circulation means in the sterilization step,
In the sterilization step and the cooling step, the pressurizing means and the exhaust means are controlled so that the inside of the treatment tank is maintained at a pressure higher than a saturated vapor pressure corresponding to the temperature in the treatment tank ,
The water supply means is capable of adjusting the flow rate in two stages, a small flow rate water supply and a large flow rate water supply with a higher flow rate than this,
In the cooling step, while circulating the water in the processing bath by the circulating means, after the water supply by the water supply means to the upper limit water level in the processing bath, with repeated be drained predetermined time by the drainage means, starting the cooling process The sterilization apparatus according to claim 1, wherein water is supplied to the processing tank by the water supply means by a small flow rate water supply before the set time elapses, and is performed by a large flow rate water supply after the set time elapses.

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