JP7447200B1 - sterilization system - Google Patents

Abstract

The present invention provides a sterilization system that can more quickly sterilize a liquid product after sterilizing various devices such as a heat exchanger. [Solution] A first heating section 11 that heat-sterilizes a liquid product, a second cooling section 21 that cools the liquid product heat-sterilized in the first heating section 11, and a heat exchanger with the liquid product in the first heating section 11. The first water hot water device 31 includes a first hot water device 31 that supplies hot water, a first circulation channel C1 that circulates a heat medium, and a water supply section 40 that supplies water to the first circulation channel C1. , the hot water is supplied to the first circulation channel C1 at a temperature for sterilizing the first heating section 11, and before heating and sterilizing the liquid product in the first heating section 11, the water is supplied from the water supply section 40 to the first circulation channel C1. Water is supplied to C1 and mixed with hot water, and the temperature of the first heating section 11 is lowered to a temperature necessary for heat sterilization of the liquid product by the hot water. [Selection diagram] Figure 3

Description

The present invention relates to a sterilization system for sterilizing liquid products.

Factories that manufacture liquid products such as carbonated drinks are equipped with sterilization systems that heat and sterilize liquid products. For example, in the sterilization system of Patent Document 1, prior to the product sterilization step of sterilizing liquid products, a device sterilization step is performed in which various devices such as a heat exchanger are heated to a temperature higher than the sterilization temperature to sterilize the various devices. .

Typically, the temperatures for sterilizing liquid products are lower than the temperatures applied to various devices during the device sterilization process. Therefore, after the device sterilization step and before the product sterilization step, a temperature stabilization step is performed to lower the various devices to the sterilization temperature of the liquid product.

It is desired that the temperature stabilization step be completed early in order to carry out the next product sterilization step. However, the sterilization system of Patent Document 1 does not specifically mention shortening the temperature stabilization process.

Japanese Unexamined Patent Publication No. 58-49149

In view of the above circumstances, an object of the present invention is to provide a sterilization system that can more quickly sterilize a liquid product after sterilizing various devices such as a heat exchanger.

One aspect of the present invention for achieving the above object includes: a first heating section that heat-sterilizes a liquid product; a second cooling section that cools the liquid product heat-sterilized in the first heating section; a first heat medium supply section that supplies a heat medium to be exchanged with the liquid product to the heating section; and a first heat medium supply section that supplies the heat medium to the first heat medium supply section, the first heating section, the second cooling section, and the first heat The first heating medium supplying section includes a first circulation channel that circulates water in the order of the medium supply section, and a water supply section that supplies water to the first circulation channel, and the first heating medium supply section circulates the heat medium through the first heating section. Water is supplied to the first circulation channel at a temperature for sterilization, and before the liquid product is heated and sterilized in the first heating section, water is supplied from the water supply section to the first circulation channel to heat the heat medium. and the temperature of the first heating section is lowered to a temperature necessary for heat sterilization of the liquid product by the heat medium , and the water supply section is configured to connect the first heating section and the first heating section in the first circulation flow path. The sterilization system is characterized by supplying water between two cooling sections .

According to the present invention, a sterilization system is provided that can more quickly sterilize a liquid product after sterilizing various devices such as a heat exchanger.

FIG. 1 is a diagram showing a schematic configuration of a sterilization system. It is a diagram showing an equipment sterilization process of the sterilization system. FIG. 3 is a diagram showing the temperature stabilization process of the sterilization system. It is a diagram showing a product sterilization process of the sterilization system.

Hereinafter, one embodiment of the sterilization system of the present invention will be described. Note that the description of the embodiments is merely an example, and the present invention is not limited to the following description.

FIG. 1 is a diagram showing a schematic configuration of a sterilization system according to this embodiment. The sterilization system 1 constitutes a part of a factory that manufactures liquid products such as drinks as liquids to be treated. For example, a group of devices (not shown) for preparing liquid products is installed upstream of the sterilization system 1, and a group of devices (not shown) for packaging the liquid products sterilized by the sterilization system 1 is installed downstream. (not shown) is installed. Of course, the upstream and downstream devices of the sterilization system 1 are not limited thereto.

The sterilization system 1 includes a first heating section 11 , a second heating section 12 , a second cooling section 21 , a first cooling section 22 , a third cooling section 23 , a first hot water device 31 , a second hot water device 32 , and a water supply section 40 It is equipped with The first heating section 11, the second heating section 12, the first cooling section 22, the second cooling section 21, and the third cooling section 23 are connected in series so that the liquid product flows in this order.

The first heating section 11 and the second heating section 12 are devices that sterilize liquid products by heating, and specifically, they are shell-and-tube type devices that indirectly exchange heat between the heat medium (for example, hot water) and the liquid product. It consists of a heat exchanger such as a plate type. The first heating section 11 and the second heating section 12 may be composed of one heat exchanger, or may be composed of a plurality of sterilizers connected together. The liquid product is first heated by the first heating section 11 and then further heated by the second heating section 12. After the liquid product is heated in the second heating section 12, it is supplied to the first cooling section 22. Although not particularly illustrated, a temperature holding tube may be provided after the second heating section 12.

Hot water is supplied to the first heating section 11 from the first water hot water device 31, and hot water is supplied to the second heating section 12 from the second hot water device 32. Although the figure illustrates a configuration in which hot water is supplied to the downstream side of the liquid product in both the first heating section 11 and the second heating section 12, there is no particular limitation on the position where the hot water is supplied.

The second cooling unit 21, the first cooling unit 22, and the third cooling unit 23 are devices that cool the liquid product, and specifically, they are shell-and-tube type devices that indirectly exchange heat between the heat medium and the liquid product. It consists of a heat exchanger such as a plate type. The second cooling unit 21, the first cooling unit 22, and the third cooling unit 23 may be configured from one heat exchanger, or may be configured by connecting a plurality of heat exchangers. The liquid product is first cooled by the first cooling section 22 , further cooled by the second cooling section 21 , and further cooled by the third cooling section 23 . After the liquid product is cooled in the third cooling section 23, it is supplied to a group of devices downstream of the sterilization system 1.

The first cooling section 22 is supplied with hot water from the second heating section 12 , and the second cooling section 21 is supplied with hot water from the first heating section 11 . Although the figure illustrates a configuration in which hot water is supplied to the downstream side of the liquid product in both the second cooling unit 21 and the first cooling unit 22, there is no particular limitation on the position where the hot water is supplied. Further, the hot water that has undergone heat exchange in the first cooling unit 22 returns to the second hot water device 32, and the hot water that has completed heat exchange in the second cooling unit 21 returns to the first water hot water device 31. The third cooling unit 23 is supplied with water (not shown) and cools the liquid product using the water as a refrigerant or medium.

The first hot water device 31 is composed of a hot water production section that produces hot water, a pump for supplying hot water, etc., and is a device that circulates hot water to the first heating section 11 and the second cooling section 21. It is an example of the 1st heat medium supply part described in a claim. Specifically, the first hot water device 31 produces hot water and supplies it to the first heating section 11 . The hot water is used to heat the liquid product in the first heating section 11. The hot water that has undergone heat exchange in the first heating section 11 is supplied to the second cooling section 21 and is used to cool the liquid product. The hot water (water) that has undergone heat exchange in the second cooling section 21 is recovered to the first water heating device 31. The first hot water device 31 produces hot water by heating recovered water or separately supplied water. In this way, the first hot water device 31, the first heating unit 11, the second cooling unit 21, and the first hot water device 31 are connected in an annular manner so that hot water circulates in this order. The hot water flow path that circulates through the first hot water device 31, the first heating section 11, and the second cooling section 21 is referred to as a first circulation flow path C1.

The second hot water device 32 is composed of a hot water production section that produces hot water, a pump for supplying hot water, etc., and is a device that circulates hot water to the second heating section 12 and the first cooling section 22. It is an example of the 2nd heat medium supply part described in a claim. Specifically, the second hot water device 32 produces hot water and supplies it to the second heating section 12 . The hot water is used to heat the liquid product in the second heating section 12. The hot water that has undergone heat exchange in the second heating section 12 is supplied to the first cooling section 22 and used to cool the liquid product. The hot water (water) that has undergone heat exchange in the first cooling unit 22 is recovered to the second water heating device 32. The second hot water device 32 produces hot water by heating recovered water or separately supplied water. In this way, these devices are connected in a ring so that hot water circulates in the order of the second hot water device 32, the second heating section 12, the first cooling section 22, and the second hot water device 32. The hot water flow path that circulates through the second hot water device 32, the second heating section 12, and the first cooling section 22 is referred to as a second circulation flow path C2.

Note that the hot water production units of the first hot water device 31 and the second hot water device 32 may be, for example, devices that produce hot water by mixing water with steam, but are not limited to such devices. The hot water production unit may be a device that heats water using an arbitrary heat source. Further, the heat medium supplied by the first hot water device 31 and the second hot water device 32 is not limited to hot water, but may be steam.

The water supply unit 40 supplies water (hereinafter referred to as cooling water) between the first heating unit 11 and the second cooling unit 21 (hereinafter referred to as water supply point P) in the flow path of hot water circulated by the first water heating device 31. It is a device that supplies The water supply unit 40 supplies cooling water to the water supply point P in a temperature stabilization process to be described later. The temperature of the cooling water is at least below the temperature (hereinafter referred to as target water temperature) set for each device in the product sterilization process described below. The water supply unit 40 stores cooling water in a container such as a tank and maintains the cooling water at a target temperature. If the target temperature is around room temperature, it is sufficient to simply store water, but if the target temperature is other than room temperature, a mechanism that adjusts the temperature of the cooling water in the tank to reach the target temperature may be used. Just set it up. Since such a temperature adjustment mechanism is well known, a detailed explanation thereof will be omitted.

The sterilization system 1 includes a control device (not shown). The control device is a programmable logic controller (PLC) or a device also called a sequencer. The control device sterilizes the liquid product by controlling the various devices described above that make up the sterilization system 1. Specifically, the control device executes an equipment sterilization process, a temperature stabilization process, and a product sterilization process.

FIG. 2 is a diagram showing the device sterilization process of the sterilization system. The solid line indicates that hot water is supplied from the first hot water device 31 and the second hot water device 32. The dotted line indicates that no liquid product is supplied from upstream and no water is supplied from the water supply section 40.

The equipment sterilization process is a process of sterilizing a liquid product and then sterilizing a group of devices for cooling it. Specifically, the control device causes the first water heating device 31 to heat water to 130° C. and circulately supply the hot water to the first heating section 11 and the second cooling section 21 . The same applies to the second hot water device 32. That is, the control device causes the second water heating device 32 to heat water to 130° C. and circulately supply the hot water to the second heating section 12 and the first cooling section 22.

The temperature of the hot water is not limited to 130°C, but may be any temperature necessary to sterilize each heating section and cooling section. Moreover, the time required for circulating and supplying hot water may be appropriately set to sterilize each heating section and cooling section. In such a device sterilization process, since liquid products are not distributed, each heating section and cooling section are heated and sterilized in the same manner as hot water.

FIG. 3 is a diagram showing the temperature stabilization process of the sterilization system. The solid line indicates that hot water is supplied from the first hot water device 31 and the second hot water device 32, and water is supplied from the water supply section 40. The dotted line indicates that no liquid product is supplied from upstream.

In the device sterilization process shown in FIG. 2, the temperature of the first heating section 11 was 130° C., but this temperature is far from the temperature required for sterilizing liquid products. For example, it is assumed that the first heating section 11 needs to be heated to 100° C. in the product sterilization process. In the temperature stabilization step, the temperature of the first heating section 11 is adjusted from 130°C to 100°C.

Specifically, the control device causes the water supply unit 40 to supply water to the water supply point P. The temperature of the water may be lower than the target of 100° C., and the amount of water may be set appropriately. Water supplied from the water supply section 40 circulates through the first circulation channel C1. Note that not only the water from the water supply section 40 but also the hot water supplied by the first water heating device 31 may be mixed in the first circulation flow path C1. In the temperature stabilization step, the temperature of the first heating section 11 is lowered, so the first circulation channel C1 only needs to supply water from the water supply section 40, and the first water heating device 31 uses a heat source such as steam to supply water. There is no need to heat it.

By supplying water from the water supply section 40 to the first circulation channel C1 and circulating it, the first heating section 11 is cooled to the target temperature of 100°C. Similarly, the temperature of the second cooling unit 21 is 100°C.

Temperature adjustment is also performed for the second circulation channel C2. In the device sterilization process shown in FIG. 2, the temperature of the second heating section 12 was 130° C., but this temperature is far from the temperature required for sterilizing liquid products. For example, it is assumed that the second heating section 12 needs to be heated to 140° C. in the product sterilization process. In the temperature stabilization step, the temperature of the second heating section 12 is adjusted from 130°C to 140°C.

Specifically, the control device causes the second hot water device 32 to circulately supply hot water of 140° C. or higher to the second circulation channel C2. The temperature of the water only needs to be higher than the target of 140° C., and the amount of water may also be set appropriately.

By circulating and supplying hot water to the second circulation channel C2, the second heating section 12 is heated to the target temperature of 140°C. Further, the temperature of the first cooling section 22 is also 140°C.

When the first heating section 11, second heating section 12, first cooling section 22, second cooling section 21, and third cooling section 23 reach the target temperatures, the control device ends the temperature stabilization step. That is, the control device allows water to circulate and stand by under the operating conditions of the manufacturing sterilization process.

FIG. 4 is a diagram showing the product sterilization process of the sterilization system. The solid line indicates that the liquid product is supplied from upstream, and hot water is supplied from the first hot water device 31 and the second hot water device 32. The dotted line indicates that water is not supplied from the water supply section 40. The underlined temperatures indicate the temperature of the liquid product, and the non-underlined temperatures indicate the temperature of the hot water.

In the product sterilization process, the liquid product is heated and sterilized in the first heating section 11 and the second heating section 12 using hot water that is circulated and supplied by the first water heating device 31 and the second water heating device 32, and the heat of the hot water is transferred to the second cooling section. 21 and the first cooling section 22, the liquid product is recovered (cooled).

Specifically, the control device causes the first hot water device 31 to circulately supply hot water to the first circulation channel C1. As for the temperature of the hot water, the inlet temperature of the first heating section 11 is 100°C. Similarly, the control device causes the second hot water device 32 to circulately supply hot water to the second circulation channel C2. The temperature of the hot water is set to 140° C. at the inlet of the second heating section 12. By circulating and supplying hot water in this way, liquid products are heat sterilized in two stages (80°C, 110°C), cooled in three stages (80°C, 50°C, 20°C), and then supplied to downstream processes. Ru.

As explained above, the sterilization system 1 performs the temperature stabilization process after the device sterilization process and before the product sterilization process. In the temperature stabilization step, water is supplied from the water supply section 40 to lower the temperature of the hot water circulating through the first circulation channel C1. As a result, the first heating section 11 and the second cooling section 21 connected to the first circulation flow path C1 are brought to a predetermined temperature (the temperature of the first heating section 11 required in the product sterilization process) by the hot water whose temperature has decreased. It can be cooled quickly. As a result, the time from the device sterilization process to the product sterilization process can be shortened, and productivity can be improved.

Note that in the past, water was not supplied by the water supply unit 40, so after the equipment sterilization process, for example, water cooled by natural heat radiation and the third cooling unit 23 is transferred from the first heating unit 11 to the third cooling unit 23. By circulating it through the three cooling sections 23, various parts of the first heating section 11, second heating section 12, first cooling section 22, and second cooling section 21 are indirectly cooled to the temperature required in the product sterilization process. Ta. Such indirect cooling and natural heat dissipation by the third cooling section 23 takes a considerable amount of time, which lengthens the time from the device sterilization process to the product sterilization process, which hinders productivity improvement. This was a contributing factor.

Further, in the temperature stabilization step, the hot water in the first circulation channel C1 is cooled from the liquid product side of the first heating section 11 and the second cooling section 21. If water is not supplied to the water supply point P, the pressure will decrease as the temperature of the hot water decreases, and the first circulation flow path C1 will become a negative pressure. Under negative pressure, there is a risk that devices such as a pump provided in the first circulation channel C1 may be damaged. In order to avoid negative pressure, it is also possible to supply steam to the first circulation flow path C1 to prevent the pressure from becoming negative pressure. However, if steam is supplied, the temperature of the first heating section 11 will not drop, and the time until the product sterilization process starts will be extended.

On the other hand, in the sterilization system 1 of the present invention, the water supply section 40 supplies water to the first circulation channel C1 in the temperature stabilization step. As a result, the drop in pressure caused by the drop in temperature of hot water mentioned above is compensated for by the supply of water, so it is possible to avoid negative pressure in the first circulation flow path C1, or to prevent it from becoming negative pressure even if it becomes negative pressure. The size can be kept small.

In this way, by supplying water, it is possible to avoid damage to devices such as the pump provided in the first circulation channel C1 due to negative pressure, and the time required for the temperature stabilization process is shortened compared to the case where steam is supplied. The product sterilization process can then be started immediately. Furthermore, since water is supplied to prevent negative pressure from occurring, energy is saved compared to the case where steam is supplied.

Furthermore, in the sterilization system 1 of the present invention, the water supply point P that supplies water to the first circulation channel C1 is downstream of the first heating section 11 and upstream of the second cooling section 21. This water supply point P is the furthest position in the first circulation channel C1 from the entrance of the first heating section 11 toward the upstream side (clockwise in the example shown in FIGS. 1-4). By arranging the water supply point P in such a manner, it is possible to avoid a sudden drop in temperature of the first heating section 11 due to water supply. Since the temperature of the first heating section 11 can be prevented from rapidly decreasing, it is possible to reduce the risk that the sterilization temperature of the first heating section 11 and the second heating section 12 will decrease in the product sterilization process.

The second heating section 12 included in the second circulation channel C2 is located at the final stage of heat sterilization from the perspective of the liquid product. In order to ensure heat sterilization of the liquid product, it is preferable to avoid lowering the temperature of the second heating section 12 below the temperature required for sterilization as much as possible. From this point of view, in the sterilization system 1 of the present invention, the water supply section 40 is not provided for the second circulation channel C2. In other words, water is not supplied to the second circulation channel C2 in the temperature stabilization step.

As shown in FIGS. 2 to 4, the temperature of the second heating section 12 in the product sterilization process must be higher than the temperature in the device sterilization process, so there is no need to supply water to the second circulation channel C2 in the first place. . However, even if the temperature in the product sterilization process needs to be lower than the temperature in the equipment sterilization process, water is not supplied. In this way, by adopting a configuration in which water is not supplied to the second circulation channel C2 in the temperature stabilization step, heat sterilization of the liquid product after the second heating section 12 can be more reliably ensured.

In addition, it is considered that time is required for the temperature stabilization step by not supplying water to the second circulation flow path C2. However, at least in comparison with the case where water is not supplied to both the first circulation flow path C1 and the second circulation flow path C2, the time required for the temperature stabilization step can be shortened.

Although the embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments.

Although the embodiment described above does not have a configuration in which water is supplied from the water supply unit 40 to the second circulation channel C2, the present invention is not limited to this, and water may be supplied to the second circulation channel C2. For example, in the case of an acidic product, since the sterilization temperature of the acidic product at the outlet of the second heating section 12 is about 95°C, it is necessary to lower the temperature from the equipment sterilization temperature (for example, 130°C). Therefore, if the temperature in the product sterilization step is lower than the temperature in the device sterilization of the second heating section 12, water may be supplied to the second circulation channel C2. Thereby, the time required for the temperature stabilization process can be shortened.

Furthermore, when water is supplied to the second circulation flow path C2, it is preferable to use the same water supply point P as the first circulation flow path C1. Thereby, similarly to the first circulation flow path C1, it is possible to avoid a sudden drop in temperature of the second heating section 12. By avoiding a rapid temperature drop in the second heating section 12, the risk of a drop in the sterilization temperature of the second heating section 12 in the product sterilization process can be reduced.

The sterilization system 1 includes a first circulation channel C1 and a second circulation channel C2, but is not limited to such a configuration. For example, the first heating section 11, the second cooling section 21, the first hot water device 31, and the first circulation channel C1 are provided, and the second heating section 12, the first cooling section 22, the second hot water device 32, and the second circulation It is also possible to adopt a configuration that does not include the flow path C2.

In the sterilization system 1, the water supply point P is arranged downstream of the first heating section 11 and upstream of the second cooling section 21, but the present invention is not limited thereto. For example, a water supply point may be provided between the first heating unit 11 and the first hot water device 31 or between the first hot water device 31 and the second cooling unit 21 in the first circulation flow path C1. As described above, there is a concern that the temperature of the first heating section 11 may decrease due to water supply, but heat sterilization can be ensured if the second heating section 12 is arranged on the downstream side. Furthermore, the water supply point P is not limited to one location, and may be provided at multiple locations.

The hot water supplied to the first heating section 11 and the second heating section 12 may be cocurrent or countercurrent with respect to the liquid product. Furthermore, the temperatures of hot water and liquid products are merely examples, and can be set as appropriate.

C1...first circulation flow path, C2...second circulation flow path, P...water supply point, 1...sterilization system, 11...first heating section, 12...second heating section, 21...second cooling section, 22...th 1 cooling section, 23... Third cooling section, 31... First hot water device (first heat medium supply section), 32... Second hot water device (second heat medium supply section), 40... Water supply section

Claims (2)

a first heating section that heat-sterilizes the liquid product;
a second cooling section that cools the liquid product heat sterilized in the first heating section;
a first heating medium supply unit that supplies a heating medium to be exchanged with the liquid product to the first heating unit;
a first circulation flow path that circulates the heat medium in the order of the first heat medium supply section, the first heating section, the second cooling section, and the first heat medium supply section;
a water supply unit that supplies water to the first circulation flow path,
The first heat medium supply section supplies the heat medium to the first circulation flow path at a temperature for sterilizing the first heating section,
Before heating and sterilizing the liquid product in the first heating section, water is supplied from the water supply section to the first circulation flow path and mixed with the heating medium, and the temperature of the first heating section is increased by the heating medium. Reduce the temperature to the temperature required for heat sterilization of the product ,
The water supply section supplies water between the first heating section and the second cooling section in the first circulation flow path.
A sterilization system characterized by: A sterilization system according to claim 1, comprising:
a second heating section that heat-sterilizes the liquid product heat-sterilized in the first heating section;
a first cooling unit that cools the liquid product heat sterilized in the second heating unit and supplies the liquid product to the second cooling unit;
a second heat medium supply unit that supplies a heat medium to the second heating unit to exchange heat with the liquid product;
a second circulation flow path that circulates the heat medium in the order of the second heat medium supply section, the second heating section, the first cooling section, and the second heat medium supply section;
A sterilization system comprising:

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