JP2024070227A - Liquid exchange method of liquid continuous sterilizer - Google Patents

Abstract

To provide a liquid exchange method of a liquid continuous sterilizer which increases an operation rate of an aseptic filling machine, and can efficiently manufacture a liquid-filled product.SOLUTION: A liquid exchange method of a liquid continuous sterilizer sterilizes a first liquid with the liquid continuous sterilizer, wherein a larger flow rate than a flow rate of the first liquid is defined as a flow rate of a cleaning liquid, a holding time is calculated from the flow rate of the cleaning liquid, T°C is calculated by Expression a from the calculated holding time and a target value of an F value, a set temperature of the liquid continuous sterilizer flowing the cleaning liquid is set at T°C or higher, then the flow rate of the cleaning liquid is set to be larger than the flow rate of the first liquid, the cleaning liquid is flowed while being sterilized by the liquid continuous sterilizer, the inside of the liquid continuous sterilizer is cleaned by the cleaning liquid, then a smaller amount of a second liquid than the flow rate of the cleaning liquid is flowed while being sterilized by the liquid continuous sterilizer under a sterilization condition equivalent to or less than a sterilization condition of the first liquid, and the cleaning liquid is exchanged with the second liquid.SELECTED DRAWING: Figure 4

Description

The present invention relates to a liquid replacement method for a continuous liquid sterilization device that sterilizes liquids such as beverages filled into containers such as bottles and paper containers.

When filling liquids such as beverages into plastic bottles or molded containers made of PET (polyethylene terephthalate), PE (polyethylene), PP (polypropylene), etc., or into paper containers, etc., liquids that may spoil due to bacteria must be sterilized and made sterile using a continuous liquid sterilization device before being filled into the container. In addition, the inside of the liquid supply system piping, which includes the surge tank, liquid delivery pipe, head tank, filling nozzle, etc. through which the sterilized liquid is delivered before being filled, must also be washed and sterilized in advance to make it sterile.

When sterilizing liquids using continuous liquid sterilization equipment, the F value, which is the sterilization value of the liquid, is calculated, and based on the historical information, it is confirmed whether the liquid has been sterilized to an extent that the quality of the liquid can be guaranteed (see Patent Documents 1 and 2).

The liquid supply system piping of a liquid filling device that fills containers with liquid undergoes CIP (Cleaning in Place) processing periodically or when switching the type of product being manufactured, i.e., when replacing the liquid, and then undergoes SIP (Sterilizing in Place) processing (see Patent Document 3).

According to Patent Document 3, CIP treatment is carried out by first flowing a cleaning liquid made of sterile water to which an alkaline agent such as sterilized caustic soda has been added, and then flowing a cleaning liquid made of sterile water to which a sterilized acidic agent has been added, through the flow path from inside the liquid supply system piping to the filling nozzle of the filling machine. CIP treatment is carried out by heating the cleaning liquid to 85°C using a continuous liquid sterilization device and circulating it through the liquid supply system piping. This removes any residue from the previous liquid that has adhered to the liquid supply system piping. It is also said that sterilization is carried out at the same time.

SIP processing is a process carried out before the liquid filling operation begins to sterilize the inside of the liquid supply system piping. The high-temperature sterilization process is carried out by passing heated steam or hot water through the liquid supply system piping that has been cleaned by CIP processing (see Patent Document 3).

After the CIP and SIP processes have been performed, the liquid is sterilized by being heated and sterilized by a continuous liquid sterilization device installed in the liquid supply system piping when the liquid is flowed through the liquid supply system piping. The sterilized liquid is filled into containers such as bottles by an aseptic filling machine.

When performing CIP and SIP treatments in the liquid supply system piping, the SIP treatment is performed after the CIP treatment, but by performing these simultaneously or consecutively, the preparation time before filling the container with liquid can be shortened. Patent Document 3 describes performing the CIP and SIP treatments simultaneously.

Patent Document 4 describes a method of performing the CIP and SIP processes simultaneously or continuously by heating the cleaning solution used in the CIP process to the temperature required for the SIP process without stopping between the processes. It also describes that the sterilization of the water used to rinse the cleaning solution is managed by calculating the F value from the heating retention time determined from the sterilization temperature and flow rate.

Furthermore, a method has been proposed for shortening the preparation time for transition from SIP processing to the process of filling liquid. Patent Document 5 describes that when transitioning from SIP processing in the liquid supply system piping to sterilization processing in which the liquid to be filled is sterilized using a continuous liquid sterilization device, the F value is calculated from the heating retention time determined from the temperature measured by multiple temperature sensors installed at any position and the flow rate of the liquid, and the temperature and flow rate of the continuous liquid sterilization device that performed the SIP processing are adjusted to the sterilization temperature and flow rate of the liquid to be filled so that the F value does not fall below a predetermined value.

Japanese Patent Application Laid-Open No. 61-92555 JP 2007-215893 A JP 2007-22600 A JP 2018-58641 A JP 2017-114496 A

In an aseptic filling machine that fills sterilized containers in a sterile atmosphere with liquid sterilized by a continuous liquid sterilization device, CIP and SIP processes are performed in the liquid supply system piping, which is the flow path through which the sterilized liquid is filled into the container, before the sterilized liquid is filled into the container. Since CIP and SIP processes take a long time, methods have been proposed to shorten these processing times. CIP is performed by circulating a cleaning liquid in the liquid supply system piping, but proposed methods include imparting a sterilizing effect to the cleaning liquid, or heating the cleaning liquid to the temperature required for SIP from the beginning, middle, or completion of CIP processing and circulating it.

When the aseptic filling machine is stopped to change the type of liquid being filled, or when the same liquid is filled for a long period of time, causing the accumulation of residues in the liquid supply system piping due to heating during sterilization of the liquid, CIP and SIP treatments are performed in the liquid supply system piping.

Different processes are carried out successively on the liquid supply system piping of the aseptic filling device: CIP process, SIP process, and sterilization process of the liquid to be filled. When transitioning from CIP process to SIP process, a rinsing process is carried out in which the cleaning liquid used in the CIP process is washed away with sterile water at room temperature, causing the temperature of the continuous liquid sterilization device to drop, and when starting the SIP process, it is necessary to raise the temperature of the continuous liquid sterilization device again to the temperature at which the SIP process is performed. This poses the problem that it takes a very long time to transition from the CIP process to the SIP process, and from the SIP process to the sterilization process of the liquid to be filled. Therefore, it has been proposed to shorten the time required for the CIP process and the SIP process by using the cleaning liquid used in the CIP process for the SIP process when transitioning from CIP process to SIP process.

When replacing the liquid being filled in an aseptic filling machine, CIP processing must be performed. This is because the liquid that was filled must be removed and the inside of the liquid supply system piping, which may contain residues of the filled liquid, must be cleaned.

However, it is not always necessary to perform SIP treatment. While the liquid is being filled, sterility within the liquid supply system piping is maintained by the SIP treatment performed before filling the liquid. If CIP treatment can be performed while maintaining sterility within the liquid supply system piping, it will be possible to replace the liquid being filled without performing SIP treatment.

If the liquid that was filled can be removed with sterilized cleaning fluid or sterile water, and the sterilized cleaning fluid or sterile water from which the liquid has been removed can be replaced with the sterilized liquid to be filled next, while sterilizing the liquid to be filled next, then the liquid to be filled can be replaced without performing SIP treatment by only performing CIP treatment in the liquid supply system piping.

According to the above-mentioned method, there is no need to perform SIP in the liquid supply system piping when changing the liquid to be filled. However, even with this method, the time required for CIP treatment is long, so there is a demand to further shorten the time required for CIP treatment when changing the liquid. When sterilizing liquid with a continuous liquid sterilization device, liquid residues accumulate significantly in places where the liquid flowing through the continuous liquid sterilization device becomes hot. By performing CIP treatment to effectively remove the liquid residues accumulated in such places, the preparation time for changing the liquid can be shortened.

The present invention has been made to solve these problems, and aims to provide a liquid replacement method for a continuous liquid sterilization device that can shorten the preparation time before filling containers with liquid, increase the operating rate of the aseptic filling machine, and efficiently manufacture liquid-filled products.

The liquid exchange method of a continuous liquid sterilization apparatus according to the present disclosure is a liquid exchange method of a continuous liquid sterilization apparatus that sterilizes a liquid by heating the liquid from the outside while the liquid is flowing, and sterilization by the continuous liquid sterilization apparatus is performed by setting an F value calculated from a retention time t minutes in a holding part of the continuous liquid sterilization apparatus, which is determined based on a flow rate of the liquid flowing through the continuous liquid sterilization apparatus, and a temperature T°C of the liquid according to the following formula a to a target value or more:
F=t×10 ^(T-T0)/Z・・・Formula a (T0℃ and Z℃ are constants determined by the liquid.)
A first liquid is sterilized by the continuous liquid sterilization apparatus, a flow rate of a cleaning liquid is set to a flow rate greater than the flow rate of the first liquid, the retention time is calculated based on the flow rate of the cleaning liquid, T°C is calculated using formula a from the calculated retention time and the target F value, the set temperature of the continuous liquid sterilization apparatus through which the cleaning liquid flows is set to T°C or higher, the flow rate of the cleaning liquid is set to the greater flow rate, the cleaning liquid is flowed while sterilizing by the continuous liquid sterilization apparatus, the inside of the continuous liquid sterilization apparatus is cleaned with the cleaning liquid, and then a second liquid at a flow rate less than the flow rate of the cleaning liquid is flowed through the continuous liquid sterilization apparatus while sterilizing under sterilization conditions equivalent to or lower than the sterilization conditions of the first liquid, and the cleaning liquid is replaced with the second liquid.

In addition, in the liquid exchange method for the continuous liquid sterilization device according to the present disclosure, it is preferable to clean the inside of the continuous liquid sterilization device with the cleaning liquid, set the flow rate of the cleaning liquid to a flow rate less than the flow rate of the cleaning liquid, and then lower the temperature of the continuous liquid sterilization device to the sterilization temperature of the second liquid.

In addition, in the liquid exchange method of the continuous liquid sterilization device according to the present disclosure, it is preferable that the flow rate is the flow rate of the holding section, and the temperature is the temperature at the end of the holding section.

In addition, in the liquid exchange method of the continuous liquid sterilization device according to the present disclosure, it is preferable to exchange the first liquid with first water, and then exchange the first water with the cleaning liquid.

In addition, in the liquid exchange method of the continuous liquid sterilization device according to the present disclosure, it is preferable to exchange the cleaning liquid with second water, and then exchange the second water with the second liquid.

According to the present invention, in an aseptic filling machine, the continuous liquid sterilization device can be cleaned in a short time and the liquid to be filled can be replaced without sterilizing the liquid supply system piping, thereby shortening the preparation time before filling containers with liquid, increasing the operating rate of the aseptic filling machine, and improving productivity.

FIG. 2 is a block diagram showing liquid supply system piping of the aseptic filling machine according to an embodiment of the present disclosure. FIG. 2 is a block diagram showing a liquid supply system piping including a continuous liquid sterilization device in an aseptic filling machine according to an embodiment of the present disclosure. FIG. 2 is a block diagram showing a liquid supply system piping from a continuous liquid sterilization device to a filling machine in aseptic filling according to an embodiment of the present disclosure. 1 is a graph showing changes over time in temperature and flow rate of the liquid and cleaning liquid in a holding section of a continuous liquid sterilization device according to an embodiment of the present disclosure. 1 is a graph showing changes over time in temperature and flow rate of liquid, water, and cleaning liquid in a holding section of a continuous liquid sterilization device according to an embodiment of the present disclosure. FIG. 2 is a diagram showing a heating medium line connected to a second stage heating section of a continuous liquid sterilization apparatus according to an embodiment of the present invention. FIG. 1 is a diagram showing fluctuations in the overall heat transfer coefficient (U value) of the second stage heating section of the continuous liquid sterilization apparatus according to an embodiment of the present invention.

An aseptic filling machine equipped with a liquid supply system piping including the continuous liquid sterilization device according to the present disclosure fills sterilized containers in a sterile atmosphere with liquid sterilized by the continuous liquid sterilization device, and seals the containers filled with liquid in a sterile atmosphere with a sterilized lid material. If the container is a paper container, there is no lid material, and the molded container is filled with liquid, and then sealed with the material that forms the container to become a finished product.

Figure 1 shows a liquid supply system piping 7 from a continuous liquid sterilizer 18 to a filling machine 2 of an aseptic filling machine that fills bottle-shaped containers 4 with sterilized liquid. As mentioned above, the containers are not limited to bottles.

The aseptic filling machine comprises a compounding device 1 that compounds the liquid, a continuous liquid sterilizing device 18 that sterilizes the compounded liquid, and a filling machine 2 that fills containers 4 such as bottles with the liquid. The compounding device 1 and a filling nozzle 2a in the filling machine 2 are connected by a liquid supply system piping 7. The filling section that includes the filling machine 2 is shielded by a filling section chamber 3.

The blending device 1 is for blending liquids such as milk coffee, black coffee, green tea, black tea, milk tea, fruit drinks, etc., in desired blend ratios. The liquid filled into the container may contain solids or fibrous materials.

The aseptic filling machine is provided with a conveying path that conveys the sterilized containers 4 to the filling machine 2 and discharges the containers 4 filled with liquid by the filling machine 2. The conveying path is generally composed of a number of wheels and grippers that grip the containers 4 arranged around each wheel.

The filling machine 2 is composed of a number of filling nozzles 2a arranged around a wheel (not shown) that rotates at high speed in a horizontal plane, and is a device that fills a fixed amount of liquid from the filling nozzles 2a into a container 4 that is held by a gripper and travels under the filling nozzles 2a in sync with the peripheral speed of the wheel while rotating the filling nozzles 2a in a rotating motion with the wheel.

In the filling section chamber 3, which shields the filling section equipped with the filling machine 2 of the aseptic filling machine, a cleaning process for cleaning the inside of the filling section chamber 3 and a sterilization process for sterilizing the inside of the filling section chamber 3 are carried out before the aseptic filling machine fills the container 4 with liquid to manufacture the product. Sterile water is required for the cleaning and sterilization processes inside the chamber, for washing the sterilized lid material, and for washing the outer surface of the container mouth after filling with liquid. To produce such sterile water, the aseptic filling machine may be equipped with a sterile water production device (not shown).

The liquid supply system piping 7 of the aseptic filling machine is equipped with, in the pipeline leading from the blending device 1 to the filling machine 2, in the order from upstream to downstream in terms of the liquid flow, a balance tank 5, a continuous liquid sterilization device 18, a manifold valve 8, an aseptic surge tank 19, and a filling machine tank 11. The aseptic filling machine also includes a cleaning liquid supply device 20 that supplies cleaning liquid to the balance tank 5, a water supply device 21 that supplies water to the balance tank 5, a heat exchanger 22 that exchanges heat between the cleaning liquid or water supplied to the balance tank 5 and the cleaning liquid or water discharged, and a controller 17 that controls the operation of the aseptic filling machine.

When carbonating liquid to produce a carbonated beverage, the liquid supply system piping 7 of the aseptic filling machine is equipped with a cooling device, a carbonation device, and a carbonated beverage surge tank. The cooling device, the carbonation device, and the carbonated beverage surge tank are provided in sequence from upstream to downstream between the aseptic surge tank 19 and the filling machine tank 11, and a carbonated beverage manifold valve is provided to allow the carbonated beverage to flow into the liquid supply system piping 7.

The continuous liquid sterilization device 18 is equipped with a first-stage heating section 12, a second-stage heating section 13, a holding tube 14 constituting a holding section, a first-stage cooling section 15, a second-stage cooling section 16, etc., and gradually heats the liquid, cleaning liquid or water supplied from the balance tank 5 while sending it from the first-stage heating section 12 to the second-stage heating section 13, holds it at a predetermined sterilization temperature in the holding tube 14 for a predetermined time, and then sends it to the first-stage cooling section 15 and the second-stage cooling section 16 to gradually cool it. The number of heating sections and cooling sections can be increased or decreased as necessary. A homogenizer may also be installed before or after the holding tube 14.

The heating section heats the outside of the tube through which the liquid flows with heated steam, or with hot water heated by heated steam. Any device that heats the outside of the tube through which the liquid flows may be used. The cooling section cools the liquid from the outside by flowing a cooled medium outside the tube through which the liquid flows. The filling machine tank 11 is a known device, so a detailed description thereof will be omitted.

The liquid is mixed in the mixing device 1 and sent from the balance tank 5 to the continuous liquid sterilizer 18, where the liquid is subjected to heat sterilization. The liquid that has been heat sterilized in the continuous liquid sterilizer 18 is stored in the aseptic surge tank 19 and then sent to the filling machine tank 11. The liquid in the filling machine tank 11 is supplied to the filling machine 2 and passes through the filling nozzle 2a to be filled into the container 4 in a sterile state. The container 4 filled with the liquid is sealed with a sterilized lid material and then discharged outside the aseptic filling machine.

The liquid supplied from the balance tank 5 is sent to the first stage heating section 12 and the second stage heating section 13 of the continuous liquid sterilization device 18, where the liquid at room temperature is heated, for example, to 130°C. When the heating section is configured with two stages, the liquid is heated from room temperature to 80°C in the first stage heating section 12, and from 80°C to 130°C in the second stage heating section.

The liquid heated in the first stage heating section 12 and the second stage heating section 13 is maintained at a target temperature, for example 130°C, in the holding tube 14. A flow meter 23 is provided somewhere in the holding tube 14.

The liquid is cooled in the first stage cooling section 15 from the holding tube 14, for example, from 130°C to 99°C. The liquid cooled in the first stage cooling section 15 is further cooled in the second stage cooling section 16, for example, and its temperature is reduced from 99°C to 30°C. The cooled liquid is sent to the aseptic surge tank 19 via the manifold valve 8.

Temperature sensors 10 are provided at various locations in the continuous liquid sterilizer 18. Temperature sensor 10a is provided in the piping between the balance tank 5 and the continuous liquid sterilizer 18, temperature sensor 10b is provided in the piping between the first stage heating section 12 and the second stage heating section 13 of the continuous liquid sterilizer 18, temperature sensor 10c is provided in the piping between the second stage heating section 13 and the holding tube 14, temperature sensor 10d is provided in the piping between the holding tube 14 and the first stage cooling section 15, temperature sensor 10e is provided in the piping between the first stage cooling section 15 and the second stage cooling section 16, and temperature sensor 10f is provided at the end of the second stage cooling section 13. Temperature sensor 10d is a temperature sensor provided at the end of the holding tube 14. The continuous liquid sterilizer 18 may be provided with temperature sensors other than the above-mentioned temperature sensor 10.

The sterilization effect of the liquid is determined by calculating the F value. The target F value is determined depending on the type of liquid, and the liquid must be heated and sterilized at or above the target F value in the continuous liquid sterilization device 18.

The F value is calculated according to the following formula a.
F=t×10 ^(T-T0)/Z・・・Formula a (T0℃ and Z℃ are constants determined by the liquid.)

In the formula, t is the time t minutes that the liquid is held in the holding tube 14. The holding tube 14 is kept warm but not heated. A vacuum insulation method is used for keeping the heat in, which can improve heat retention. The holding tube 14 is a pipe with an inner diameter of 10 to 100 mmφ and a length of 5 to 200 m, and is either straight and folded or spiral. For example, a holding tube 14 with an inner diameter of 72.3 mmφ and a length of 130 m has a holding capacity of 533 L, and with a flow rate of 450 L/min, the holding time t minutes is 1.2 minutes.

T is the temperature T°C at the end of the holding tube 14, which is the temperature measured by temperature sensor 10d. Comparing the temperature measured by temperature sensor 10c provided at the inlet of the holding tube 14 with the temperature measured by temperature sensor 10d, the temperature measured by temperature sensor 10d is slightly lower because the holding tube 14 is not heated. Therefore, T°C is the temperature measured by temperature sensor 10d, which measures the temperature at the end of the holding tube 14.

T0 and Z are constants determined by the liquid. Determined by the liquid, T0 and Z are changed because the bacteria to be sterilized differ depending on the pH of the liquid. For example, in a liquid with a pH of 4.6 or higher, a bactericidal effect capable of killing botulinum bacteria is required, so T0 is set to 121.1°C and Z is set to 10°C. In a liquid with a pH of 4.0 or higher but less than 4.6, some bacteria grow, so T0 is set to 85°C and Z is set to 7.8°C. In a liquid with a pH of less than 4.0, bacteria do not grow, so a bactericidal effect sufficient to kill mold and yeast is required, so T0 is set to 65°C and Z is set to 5°C. T0 and Z shown for each pH are examples and may be replaced with other values. The target F value to be calculated is determined by the liquid and the specific composition of the liquid, etc.

The liquid sterilized by the continuous liquid sterilization device 18 is sent to and stored in an aseptic surge tank 19. The stored liquid is sent from the aseptic surge tank 19 to the filling machine tank 11 and stored therein. The liquid is sent from the filling machine tank 11 to the filling machine 2, and a fixed amount of liquid is filled into sterilized containers 4 from the filling nozzle 2a in the filling section chamber 3, which has a sterile atmosphere. The containers 4 filled with the liquid are sealed with sterilized lids and discharged from the aseptic filling machine.

When changing the liquid to be filled to another liquid after the aseptic filling operation is completed, CIP and SIP treatments are performed inside the liquid supply system piping 7. During liquid filling operations, the location where liquid residue adheres most is the second stage heating section 13. This is the location where the contents are rapidly heated to a high temperature, and residue adhesion due to thermal denaturation of proteins is particularly severe, particularly in liquids containing milk. Furthermore, the higher the temperature and the greater the liquid flow rate, the greater the amount of inorganic salt residue from the product ingredients. CIP treatment removes residue from the liquid that was previously filled.

The CIP process in the liquid supply system piping 7 is performed by circulating the cleaning liquid supplied from the cleaning liquid supply device 20 to the balance tank 5 within the liquid supply system piping 7. As shown in FIG. 1, a circulation path is formed by providing a return path 6 to the content supply system piping 7 in order to circulate the cleaning liquid. An upstream circulation path may also be formed by providing an upstream return path 6a to the upstream piping section 7a that runs from the balance tank 5 through the continuous liquid sterilizer 18 to the manifold valve 8.

The cleaning liquid may be distributed from the filling machine manifold 2b of the filling machine 2 to the filling nozzle 2a through the manifold valve 8 via the filling machine tank 11, without being circulated through the upstream circulation path. The cleaning liquid flowing out from the filling nozzle 2a is received by a cup 9 joined to the tip of the filling nozzle 2a, and the cleaning liquid flowing out from multiple filling nozzles 2a is collected by the circulation manifold 25 and returned to the manifold valve 8 through the downstream return path 6b. The cleaning liquid may be circulated through the liquid supply system piping 7 via the manifold valve 8 through the upstream return path 6a.

Cups 9 that can be attached and detached are placed on the openings of the filling nozzle 2a of the filling machine 2. When performing CIP processing, each cup 9 is joined to the opening at the tip of the filling nozzle 2a of the filling machine 2 by an actuator (not shown), and the cup 9 that is the starting point of the downstream return path 6b is connected to the opening of the filling nozzle 2a.

As shown by the thick line in FIG. 2, the cleaning liquid supplied from the cleaning liquid supply device 20 to the balance tank 5 flows from the balance tank 5 to the continuous liquid sterilization device 18, where it is sterilized by being heated by the continuous liquid sterilization device 18, reaches the manifold valve 8, returns to the balance tank 5 via the upstream return path 6a, and may be circulated through the upstream circulation path.

As shown by the thick line in Figure 3, the cleaning liquid supplied from the cleaning liquid supply device 20 to the balance tank 5 flows from the balance tank 5 to the continuous liquid sterilization device 18, where it is sterilized by being heated, passes through the manifold valve 8, the aseptic surge tank 19, and the filling machine tank 11, reaches the filling machine 2, flows from the filling machine manifold 2b to the filling nozzle 2a, is received by the filling nozzle 2a in a cup 9, is collected in the circulation manifold 25, passes through the downstream return path 6b, and returns to the balance tank 5 from the manifold valve 8 via the upstream return path 6a, and may circulate within the liquid supply system piping 7.

The cleaning solution is an alkaline cleaning solution made by adding alkaline chemicals such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium phosphate, sodium hypochlorite, surfactants, and chelating agents such as sodium gluconate and ethylenediaminetetraacetic acid to water, or an acidic cleaning solution made by adding acidic chemicals such as nitric acid or phosphoric acid. The water can be any water that does not contain foreign matter, such as ion-exchanged water, distilled water, or tap water.

The alkaline cleaning solution includes, but is not limited to, lithium carbonate, ammonium carbonate, magnesium carbonate, calcium carbonate, propylene carbonate, and mixtures thereof. It may also include bicarbonates such as sodium bicarbonate, potassium bicarbonate, lithium bicarbonate, ammonium bicarbonate, magnesium bicarbonate, and calcium bicarbonate, and sesquicarbonates such as sodium sesquicarbonate, potassium sesquicarbonate, lithium sesquicarbonate, and mixtures thereof.

In addition to the above-mentioned nitric acid and phosphoric acid, acidic cleaning solutions include hydrochloric acid, sulfuric acid, acetic acid, citric acid, lactic acid, formic acid, glycolic acid, methanesulfonic acid, sulfamic acid, and mixtures thereof, but are not limited to these.

The cleaning solution may contain hypochlorite, hydrogen peroxide, peracetic acid, peroctanoic acid, persulfate, perborate, hydrosulfite, thiourea dioxide, and other bleaching agents, as well as percarbonates. Furthermore, the cleaning solution may contain water softeners such as aluminosilicates and polycarboxylates, and may contain anti-redeposition agents such as sodium phosphate, sodium polyacrylate, and sodium carboxylate. Furthermore, enzymes, solvents, fatty acids, foam regulators, active oxygen sources, and the like may be added to the cleaning solution.

In the CIP process, the cleaning liquid is not limited to being passed through an alkaline cleaning liquid followed by an acidic cleaning liquid. For example, an acidic cleaning liquid may be passed through followed by an alkaline cleaning liquid, or an acidic cleaning liquid and an alkaline cleaning liquid may be passed through alternately multiple times. Also, the CIP process may be performed by passing only either an acidic cleaning liquid or an alkaline cleaning liquid.

When the operation buttons on the panel (not shown) of the controller 17 are operated, the CIP process is performed for each of the liquid supply system pipes 7 in a predetermined procedure. A constant amount of cleaning liquid is constantly or intermittently supplied from the cleaning liquid supply device 20, and while circulating the cleaning liquid, it removes any residue from the previous liquid adhering to the inside of the liquid supply system pipes 7.

As mentioned above, when changing the liquid to be filled to another liquid after the aseptic filling operation of the liquid is completed, CIP treatment is performed in the liquid supply system piping 7. However, normally, SIP treatment is performed in the liquid supply system piping 7 after CIP treatment.

When the first liquid is filled into the container 4 while being sterilized by the continuous liquid sterilization device 18, and then the first liquid is replaced with the second liquid, if the sterility of the liquid supply system piping 7 can be maintained while the liquid is replaced, there is no need to perform SIP processing in the liquid supply system piping 7.

Since the first liquid was filled into the container 4 while being sterilized by the continuous liquid sterilization device 18, residues of the first liquid were found to adhere to the inside of the liquid supply system piping 7. There was a particularly large amount of residue of the first liquid inside the continuous liquid sterilization device 18, and the adhesion of the residues of the first liquid was particularly severe inside the second stage heating section 13 where the first liquid was heated to a high temperature.

Therefore, if the sterility inside the liquid supply system piping 7 can be maintained, SIP treatment does not have to be performed, but CIP treatment must be performed inside the liquid supply system piping 7 where residues of the first liquid are attached.

After the filling of the first liquid is completed, the cleaning liquid is supplied to the balance tank 5 from the cleaning liquid supply device 20 without changing the sterilization conditions in the liquid continuous sterilization device 18 for the first liquid, the cleaning liquid supplied to the balance tank 5 is sterilized by the liquid continuous sterilization device 18, and the sterilized cleaning liquid is used to perform CIP treatment in the liquid supply system piping 7. After the CIP treatment is completed, the cleaning liquid is replaced with the second liquid without changing the sterilization conditions in the liquid continuous sterilization device 18. After the cleaning liquid is removed by the second liquid, filling of the second liquid begins. As described above, by replacing the first liquid with the cleaning liquid and then with the second liquid while maintaining the sterilization conditions in the liquid continuous sterilization device 18 for the first liquid, the liquid to be filled in the container can be replaced from the first liquid to the second liquid without performing SIP treatment.

However, the above-mentioned method requires a long time for CIP treatment. In order to shorten the time for CIP treatment, it is necessary to increase the flow rate of the cleaning liquid when performing CIP treatment. By increasing the flow rate of the cleaning liquid, the residue of the first liquid adhering to the inside of the liquid supply system piping 7 can be removed in a short time. Increasing the flow rate of the flowing cleaning liquid increases the flow rate, and the faster flow rate of the cleaning liquid increases the physical peeling force, improving the cleaning effect.

When replacing the first liquid to be sterilized by the continuous liquid sterilization device 18 with the second liquid, the following method is used.

Figure 4 shows the flow rate measured by the flowmeter 23 provided in the holding tube 14 and the temperature measured by the temperature sensor 10d provided at the end of the holding tube 14 over time when the liquid to be sterilized in the continuous liquid sterilization device 18 is replaced from the first liquid to the second liquid.

The first liquid is sterilized by the continuous liquid sterilization device 18 by flowing the first liquid at a predetermined temperature and a predetermined flow rate, and then filled into the container 4. The F value is calculated from the temperature T°C measured by the temperature sensor 10d at the end of the holding tube 14 and the retention time t minutes of the holding tube 14 calculated from the flow rate inside the holding tube 14. When the F value reaches or exceeds the target value, the first liquid is sterilized. The sterilized first liquid is cooled by the first stage cooling section 15 and the second stage cooling section 16 and filled into the container 4.

After the filling of the first liquid is completed, the cleaning liquid is supplied from the cleaning liquid supply device 20 to the balance tank 5. The supplied cleaning liquid is passed through the continuous liquid sterilization device 18, which maintains the temperature and flow rate of the holding tube 14, which are the sterilization conditions of the first liquid, and the first liquid is replaced with the cleaning liquid while sterilizing the cleaning liquid. The replaced cleaning liquid is sterilized by the continuous liquid sterilization device 18 under the same conditions as the first liquid. The mixture of the first liquid and the cleaning liquid is discharged from the aseptic filling machine until the first liquid in the liquid supply system piping 7 is replaced with the cleaning liquid. It is confirmed that the first liquid in the liquid supply system piping 7 has been replaced with the cleaning liquid. This is confirmed by measuring the electrical conductivity of the discharged mixed liquid.

After filling with the first liquid is completed, the cleaning liquid is passed through the continuous liquid sterilization device 18. At this time, the cooling of the first stage cooling section 15 and the second stage cooling section 16 can be stopped or the cooling conditions can be relaxed, and the temperature of the cleaning liquid does not have to be cooled to room temperature. When the mixture of the first liquid and the cleaning liquid is discharged, the mixture and the supplied cleaning liquid are heat exchanged by the heat exchanger 26, making it possible to raise the temperature of the supplied cleaning liquid from room temperature, and reducing the heating energy of the cleaning liquid in the continuous liquid sterilization device 18.

The cleaning liquid replaced with the first liquid is used to perform CIP treatment in the liquid supply system piping 7. At this time, in order to shorten the time for CIP treatment, the flow rate of the cleaning liquid is increased, and a cleaning liquid with a flow rate greater than that of the first liquid is passed from the liquid continuous sterilization device 18 into the liquid supply system piping 7. Increasing the flow rate shortens the retention time t minutes in the holding tube 14. If the temperature is left unchanged and only the flow rate is increased, the calculated F value becomes smaller and falls below the target F value, resulting in poor sterilization of the cleaning liquid. When the retention time is set to t minutes, the temperature T°C must be increased in order to make the calculated F value equal to or greater than the target value. The temperature T°C that must be increased is calculated using formula a. For example, if the higher flow rate is twice the flow rate of the first liquid, t minutes will be 1/2. If the sterilization temperature T°C of the first liquid is 121.1°C, and T0 is set to 121.1°C and Z is set to 10°C, in order to keep the F value the same, the new T°C must be set to 124.1°C. In other words, the temperature at the end of the holding tube 14 must be increased by 3°C.

As described above, the flow rate of the cleaning liquid for the CIP treatment is determined to be greater than the flow rate of the first liquid, the retention time t minutes in the holding tube 14 is calculated from the greater flow rate, and T°C is calculated from the calculated retention time t minutes and the target value of the F value using formula a. The greater flow rate is preferably 1.1 times or more and 5 times or less than the flow rate of the first liquid. If it is less than 1.1 times, the cleaning effect of the CIP treatment will not improve and the CIP treatment time cannot be sufficiently shortened. A flow rate of more than 5 times will require a high-capacity pump, which will increase the amount of capital investment. It is preferably 1.3 times or more and 3 times or less.

As shown in FIG. 4, after replacing the first liquid with the cleaning liquid, the temperature setting of the heating section of the continuous liquid sterilization device 18 is changed without changing the flow rate so that the temperature measured by the temperature sensor 10d at the end of the holding tube 14 rises to the calculated temperature T°C described above. After confirming that the temperature measured by the temperature sensor 10d has risen to or above the calculated temperature, the flow rate is changed to a higher flow rate.

If the flow rate of the cleaning liquid is increased when the temperature of the cleaning liquid does not rise above the calculated temperature T°C, as can be seen from formula a, t will become large before T°C reaches the calculated temperature, and the F value will not reach the target value. This will result in poor sterilization of the cleaning liquid, and the liquid supply system piping 7 will become contaminated with bacteria. To avoid this, the process of increasing the flow rate after the temperature rises must be observed. By observing the above process, the liquid can be replaced while maintaining the sterility of the liquid supply system piping 7.

By using the calculated temperature and determined flow rate, the cleaning liquid is sterilized by the continuous liquid sterilization device 18 to a level equal to or higher than the target F value.

After replacing the first liquid with the cleaning liquid, the temperature and flow rate of the cleaning liquid are set, and the circulation path is set to circulate the sterilized cleaning liquid. As shown in FIG. 2, this circulation path may be an upstream circulation path that flows from the upstream piping path 7a through the manifold valve 8 to the upstream return path 6a. The downstream side of the manifold valve 8 is filled with sterilized cleaning liquid, and the downstream circulation path may be CIP-treated by circulating the sterilized cleaning liquid in the downstream circulation path formed by the downstream piping section 7b and the downstream return path 6b. A heating device may be provided in the downstream piping section 7b or the downstream return path 6b to heat the circulating cleaning liquid.

As shown in FIG. 3, the cleaning liquid can be passed through the upstream piping section 7a, the downstream piping section 7b, the downstream return path 6b, and the upstream return path 6a to form a circulation path from the continuous liquid sterilization device 18 to the filling valve 2a, and the cleaning liquid can be circulated through this circulation path to perform the CIP treatment.

The cleaning liquid sterilized to above the target F value under the sterilization conditions of the elevated temperature and high flow rate of the continuous liquid sterilization device 18 is circulated through a set circulation path to perform CIP treatment. The cleaning liquid held in the holding tube 14 may be allowed to flow downstream without being cooled in the first stage cooling section 15 and the second stage cooling section 16. The cleaning effect is enhanced by flowing it in a heated state for sterilization. It may also be allowed to flow at a temperature below the boiling point of water, which is more effective for cleaning, by cooling it appropriately to 60°C or higher and 95°C or lower. It may also be allowed to flow after being cooled to room temperature.

The CIP treatment is carried out for a predetermined time. The predetermined time may be a time empirically derived from the type of first liquid, the total flow rate flowed by filling, the sterilization temperature, etc. The predetermined time for performing the CIP treatment may be determined by calculating the overall heat transfer coefficient of the second stage heating section 13 of the continuous liquid sterilization device 18, as described below.

Temperature sensors 10a to 10f are provided at various locations in the continuous liquid sterilization device 18, as shown in FIG. 1. 10b is located at the inlet of the second stage heating section 13, and 10c is located at the outlet of the second stage heating section 13. Information on the temperatures measured by these temperature sensors is sent to the controller 17.

As shown in FIG. 6, a heating medium line 24 is connected to supply a heating medium to the second stage heating section 13, which is the most downstream heating section, in order to heat the second stage heating section 13.

The heating medium line 24 is provided with a heating steam supply section 27 that supplies heating steam into the heating medium line 24, and the heating medium flowing through the heating medium line 24 is heated to a high temperature by the heating steam supplied from the heating steam supply section 27. The heating medium may be heated by an electric heater. Furthermore, the heating medium line 24 is provided with a pressure pump 28. Water is a suitable heating medium. Oil can also be used instead of water, but a heating device must be provided.

The heating medium line 24 is supplied to the heating pipe 13a of the second stage heating section 13, and as shown in FIG. 6, the heating medium flows in the heating pipe 13a in a direction opposite to the direction in which the liquid flows in the liquid supply system pipe 7. The heating medium may also flow in the same direction as the liquid flows in the liquid supply system pipe 7 in parallel. A temperature sensor 10g is provided at the inlet of the heating pipe 13a, and a temperature sensor 10h is provided at the outlet of the heating pipe 13a.

As shown in FIG. 6, the heating medium flowing through the heating medium line 24 is supplied to the heating pipe 13a and heats the liquid flowing through the second stage heating section 13. The heating medium that heats the liquid in the second stage heating section 13 drops in temperature at the outlet of the heating pipe 13a, but is heated by the heating steam supplied from the heating steam supply section 27, and the heated heating medium is supplied to the heating pipe 13a and circulated.

The second stage heating section 13 of the continuous liquid sterilizer 18 is the section where the contents are sterilized by heating at high temperature, and the inner surface of the heating pipe 13a is prone to staining such as scorching. The overall heat transfer coefficient of the heating pipe 13a of the second stage heating section 13, which is the most prone to staining, is calculated, and the CIP treatment in the continuous liquid sterilizer 18 is performed efficiently. It is possible to calculate the overall heat transfer coefficients of the other heating and cooling sections of the continuous liquid sterilizer 18, and the CIP treatment should be completed when the overall heat transfer coefficients of all heating and cooling sections are calculated and all of the overall heat transfer coefficients reach the target value. However, the most downstream heating section has the most residual liquid, and the CIP treatment is completed when the overall heat transfer coefficient of the most downstream heating section reaches the target value, and this may be set as a specified time.

Figure 7 shows the change over time in the overall heat transfer coefficient (U value) versus production time. The higher the overall heat transfer coefficient (U value), the easier it is to transfer temperature. The overall heat transfer coefficient of the heating pipe 13a gradually decreases with the production of the filled product due to adhesions such as burnt liquid that adhere to the inside of the heating pipe 13a when the liquid is sterilized. The overall heat transfer coefficient that has decreased due to production increases by performing CIP treatment, and is restored to the overall heat transfer coefficient before the start of production of the filled product. In other words, the goal of completing the CIP treatment is for the overall heat transfer coefficient of the heating pipe 13a to recover to the overall heat transfer coefficient in a state where there is no adhesion of liquid residue inside the heating pipe 13a. A target value for the decreased overall heat transfer coefficient is set, and CIP treatment is performed to complete the CIP treatment when the overall heat transfer coefficient of the heating pipe 13a reaches the target value. This allows the CIP treatment to be performed efficiently without wasting time on the CIP treatment.

The controller 17 stores various data, calculates an overall heat transfer coefficient from the measured temperature transmitted from the heating pipe 13a of the second stage heating unit 13, judges whether the calculated overall heat transfer coefficient has reached a target value, and judges that the CIP treatment is completed when the overall heat transfer coefficient has reached the target value, and completes the CIP treatment in the liquid supply system pipe 7. This completion judgment is for the second stage heating unit 13 of the continuous liquid sterilization device 18, but since the second stage heating unit of the continuous liquid sterilization device 18 is most heavily soiled, the judgment of the completion of the CIP treatment in the second stage heating unit 13 of the continuous liquid sterilization device 18 may be the judgment of the completion of the CIP treatment in the liquid supply system pipe 7. In other words, the time until the overall heat transfer coefficient reaches the target value may be set as the predetermined time.

To calculate the overall heat transfer coefficient, as shown in Figure 6, a temperature sensor 10b is provided at the inlet of the cleaning liquid in the heating pipe 13a of the second stage heating section 13 of the continuous liquid sterilization device 18, a temperature sensor 10c is provided at the outlet of the cleaning liquid, a temperature sensor 10g is provided at the inlet of the heating medium in the heating pipe 13a, and a temperature sensor 10h is provided at the outlet of the heating medium in the heating pipe 13a. The temperatures are measured by these temperature sensors, and the temperature of temperature sensor 10b is T1, the temperature of 10c is T2, the temperature of 10g is T3, and the temperature of 10h is T4.

The measured temperatures T1, T2, T3 and T4 are sent to the controller 17, which calculates the overall heat transfer coefficient. The overall heat transfer coefficient is calculated as follows:

First, the logarithmic mean temperature difference ΔT is calculated using the following formula (Formula 1).

Next, the heat quantity Q in the second stage heating section 13 is calculated by the following formula (2) using the temperatures T1, T2, and the flow rate R (L/h). However, when the specific heat is 1 (kcal/kg·°C) and the specific weight is 1 (kg/L), Q = 1×1×R×(T2-T1) (2)
The flow rate R is measured by a flow meter 23 and transmitted to the controller 17. A flow meter may be provided in the heating pipe 13a of the second stage heating section 13, and the measured value by this flow meter may be used.

Moreover, the heat transfer area A (m ² ) of the heating pipe 13a of the second stage heating section 13 is determined in advance.

From the above, the controller 17 calculates the overall heat transfer coefficient (U value) of the second stage heating section 13 by the following formula (3).
U = Q / (A x △T) (3 formulas)

As described above, the overall heat transfer coefficient of the second stage heating section 13 is calculated during the CIP process, and when the overall heat transfer coefficient reaches the target value, the CIP process is completed and the next process can be started. Therefore, there is no need to continue the CIP process any longer than necessary, and the CIP process can be carried out efficiently.

The controller 17 determines that the CIP process is complete when the calculated overall heat transfer coefficient reaches a predetermined target value.

As shown in Fig. 4, the CIP treatment continues while the cleaning liquid is flowing, but after the CIP treatment is performed for a predetermined time, the CIP treatment is completed and the flow rate of the cleaning liquid is first reduced. The reduced flow rate is determined by the sterilization conditions when the second liquid to be filled next is sterilized by the continuous liquid sterilization device 18. This flow rate is less than the flow rate of the cleaning liquid. It is confirmed by the flow meter 23 that the flow rate of the cleaning liquid has been reduced to the flow rate determined by the sterilization conditions of the second liquid. After it is confirmed that the flow rate has been reduced, the sterilization temperature of the continuous liquid sterilization device 18 is reduced to the sterilization temperature of the second liquid.

It is confirmed that the temperature measured by the temperature sensor 10d has dropped to the sterilization temperature of the second liquid. After it is confirmed that the temperature of the cleaning liquid has dropped to the sterilization temperature of the second liquid, the cleaning liquid is replaced with the second liquid.

The sterilization conditions for the second liquid must be equal to or lower than the sterilization conditions for the first liquid. If the first liquid has a pH of 4.6 or higher, the second liquid may have any pH. However, if the first liquid has a pH of 4.0 or higher but lower than 4.6, the second liquid must not have a pH of 4.6 or higher. This is because if bacteria remaining under the sterilization conditions for the first liquid remain in the liquid supply system piping 7, the bacteria remaining in the liquid supply system piping 7 cannot be sterilized even if the second liquid is sterilized under sterilization conditions of pH 4.6 or higher.

If the temperature of the cleaning liquid is lowered when the flow rate of the cleaning liquid has not been reduced sufficiently, that is, when t remains small, then as can be seen from formula a, the target F value will not be reached. This will result in poor sterilization of the cleaning liquid, and the liquid supply system piping 7 will become contaminated with bacteria. To avoid this, the process of lowering the temperature after lowering the flow rate must be observed. By observing the above process, the liquid can be replaced while maintaining sterility within the liquid supply system piping 7.

After the cleaning liquid in the liquid supply system piping 7 is removed by the second liquid, it is confirmed that it has been replaced with the second liquid, and then the filling of the second liquid begins. By replacing the first liquid, the cleaning liquid replacing the first liquid, and the second liquid while sterilizing them with a sterilization value equal to or higher than the target F value using the continuous liquid sterilization device 18, the liquid to be filled can be replaced using only CIP treatment, without performing SIP treatment. By increasing the flow rate of the cleaning liquid, the CIP treatment time can be shortened during replacement.

So far, it has been described that when replacing a first liquid with a second liquid, the first liquid is replaced with a cleaning liquid, and the replaced cleaning liquid is replaced with a second liquid. As shown in FIG. 5, a method of replacing the first liquid with water, replacing the replaced water with a cleaning liquid, replacing the replaced cleaning liquid with water, and replacing the replaced water with a second liquid will be described.

The first liquid is sterilized by the continuous liquid sterilization device 18 by flowing it at a predetermined temperature and a predetermined flow rate, and then filled into the container 4. The F value is calculated from the temperature T°C measured by the temperature sensor 10d at the end of the holding tube 14 and the retention time t minutes of the first liquid in the holding tube 14, which is calculated from the flow rate in the holding tube 14. The first liquid is sterilized by setting the calculated F value to a target value or higher. The sterilized first liquid is cooled by the first stage cooling section 15 and the second stage cooling section 16, and filled into the container 4.

After filling of the first liquid is completed, water is supplied from the water supply device 21 to the balance tank 5, and the first liquid is replaced with the first water while maintaining the sterilization conditions of the first liquid in the continuous liquid sterilization device 18, that is, the temperature and flow rate. The supplied first water is sterilized by the continuous liquid sterilization device 18 under the same conditions as the first liquid. The mixture of the first liquid and the first water is discharged from the aseptic filling machine until the first liquid in the liquid supply system piping 7 is replaced with water. It is confirmed that the first liquid in the liquid supply system piping 7 has been replaced with water. This is confirmed by measuring the electrical conductivity of the discharged mixed liquid.

After filling of the first liquid is completed, the first water is supplied to the continuous liquid sterilization device 18 and heat-sterilized. At this time, the cooling of the first stage cooling section 15 and the second stage cooling section 16 may be stopped or the cooling conditions may be relaxed, and the first liquid may be removed without cooling the temperature of the first water to room temperature. When discharging the mixture of the first liquid and the first water, heat exchange between the mixture and the supplied first water is performed by the heat exchanger 26, making it possible to raise the temperature of the first water supplied to the balance tank 5 from room temperature, and reducing the heating energy of the first water in the continuous liquid sterilization device 18.

After the first liquid in the liquid supply system piping 7 is replaced with the first water, the first water is replaced with a cleaning liquid. The replaced cleaning liquid is used to perform CIP treatment in the liquid supply system piping 7. After the CIP treatment is completed, the cleaning liquid is replaced with the second water, and the replaced second water is replaced with the second liquid. In this way, by replacing the first liquid supplied to the continuous liquid sterilization device 18 with the second liquid, the liquid to be filled in the container 4 can be replaced from the first liquid to the second liquid without performing SIP in the liquid supply system piping 7.

The first liquid may be replaced with first water, the replaced first water may be replaced with a cleaning liquid, and the cleaning liquid may be directly replaced with the second liquid without replacing the cleaning liquid with the second water. The first liquid may be replaced with a cleaning liquid, the replaced cleaning liquid may be replaced with second water, and the second water may be replaced with the second liquid. By replacing the cleaning liquid with the second water and then with the second liquid, contamination of the second liquid with the cleaning liquid can be prevented. It is preferable to replace the second liquid with the second water in order to prevent contamination of the second liquid with the cleaning liquid.

The cleaning liquid is used to perform CIP treatment inside the liquid supply system piping 7, but the flow rate of the cleaning liquid is increased to shorten the CIP treatment time, and a flow rate of cleaning liquid greater than the flow rate of the first liquid is passed from the liquid continuous sterilization device 18 into the liquid supply system piping 7. Increasing the flow rate shortens the retention time t minutes in the holding tube 14. As a result, the calculated F value becomes smaller, and the cleaning liquid with an increased flow rate will have poor sterilization results. When the retention time is t minutes, the temperature T°C must be increased to achieve the target F value or higher. The temperature T°C that must be increased is calculated using formula a. The calculation method is as described above.

The flow rate of the cleaning liquid used in the CIP treatment is determined to be greater than the flow rate of the first liquid, the retention time t minutes in the holding tube 14 is calculated from the greater flow rate, and T°C is calculated using formula a from the calculated retention time t minutes and the target F value. The greater flow rate should be 1.1 times or more and 5 times or less than the flow rate of the first liquid. If it is less than 1.1 times, the cleaning effect of the CIP treatment will not improve and the CIP treatment time cannot be sufficiently shortened. A flow rate of more than 5 times will require a high-capacity pump, which will increase capital investment.

As shown in FIG. 5, the first liquid in the liquid supply system piping 7 is replaced with the first water without changing the sterilization conditions of the continuous liquid sterilization device 18. The method of replacing the first liquid with the first water is the same as the method of replacing the first liquid with the cleaning liquid described above. After the first liquid is replaced with the first water, the temperature setting of the heating section of the continuous liquid sterilization device 18 is changed without changing the flow rate so that the temperature measured by the temperature sensor 10d at the end of the holding tube 14 rises to the calculated temperature T°C.

After confirming that the temperature measured by the temperature sensor 10d has risen to or above the calculated temperature T°C, the flow rate is changed to a higher flow rate while replacing the first water with the cleaning liquid. After changing the flow rate of the first water to a higher flow rate, the first water may be replaced with the cleaning liquid.

If the flow rate of the first water or cleaning liquid supplied is increased when the temperature of the first water or cleaning liquid does not rise above the calculated temperature, as can be understood from formula a, when T°C does not reach the calculated temperature, t will become large and the target F value will not be reached. This will result in poor sterilization of the first water or cleaning liquid, and the liquid supply system piping 7 will become contaminated with bacteria. To avoid this, the process of increasing the flow rate after the temperature has risen, as described above, must be observed. By observing the above process, the liquid can be replaced while maintaining sterility in the liquid supply system piping 7.

By setting the calculated temperature and determined flow rate, the first water or cleaning liquid is sterilized by the liquid continuous sterilization device 18 to a level equal to or higher than the target F value.

After replacing the first water with the cleaning liquid, a circulation path for the sterilized cleaning liquid that flows at a high flow rate is set. As shown in FIG. 2, the circulation path may be an upstream circulation path that flows from the upstream piping section 7a via the manifold valve 8 to the upstream return path 6a. The downstream side from the manifold valve 8 is filled with sterilized cleaning liquid, and the downstream circulation path may be CIP-treated by circulating the sterilized cleaning liquid in the downstream circulation path formed by the downstream piping section 7b and the downstream return path 6b. A heating device may be provided in the downstream piping section 7b or the downstream return path 6b to heat the circulating cleaning liquid and improve the cleaning effect.

The cleaning liquid sterilized to above the target F value under the sterilization conditions of the temperature raised by the continuous liquid sterilization device 18 and the high flow rate is circulated through the set circulation path, and the CIP process is performed. The cleaning liquid held at a high temperature in the holding tube 14 may be allowed to flow downstream without being cooled in the first stage cooling section 15 and the second stage cooling section 16. The cleaning effect is enhanced by flowing it in a heated state for sterilization. It may also be allowed to flow at a temperature below the boiling point of water, which is more effective for cleaning, by appropriately cooling it to 60°C or higher and 95°C or lower. It may also be allowed to flow after being cooled to room temperature.

The CIP process is carried out for a predetermined time. The predetermined time may be a time empirically derived from the type of first liquid, the total flow rate flowed by filling, the sterilization temperature, etc. It may also be determined by calculating the overall heat transfer coefficient of the second stage heating section 13 of the continuous liquid sterilization device 18 as described above.

As shown in FIG. 5, the CIP process continues while the cleaning liquid is flowing, but after a predetermined time, the CIP process is completed and the cleaning liquid is replaced with second water. The second water is supplied to the balance tank 5 from the water supply device 20 in the same manner as the first water, and the supplied second water is sterilized by the liquid continuous sterilization device 18.

After CIP is complete, the flow rate of the second water, which is flowed in place of the cleaning liquid, is reduced. The reduced flow rate is determined by the sterilization conditions when the second liquid to be filled next is sterilized by the liquid continuous sterilization device 18. The flow rate of the second liquid is less than the flow rate of the cleaning liquid. The flow meter 23 is used to confirm that the flow rate of the second water has been reduced to the flow rate determined by the sterilization conditions of the second liquid. After it is confirmed that the flow rate of the second water has been reduced, the sterilization temperature of the liquid continuous sterilization device 18 is reduced to the sterilization temperature of the second liquid.

It is confirmed that the temperature measured by the temperature sensor 10d has dropped to the sterilization temperature of the second liquid. After it is confirmed that the temperature of the second water has dropped to the sterilization temperature of the second liquid, the second water is replaced with the second liquid.

Although the flow rate is reduced while replacing the cleaning solution with the second water, the cleaning solution may be replaced with the second water after the flow rate is reduced.

The sterilization requirements of the second liquid must be equal to or less than the sterilization requirements of the first liquid, as discussed above.

If the temperature of the cleaning liquid or second water is lowered when the flow rate of the cleaning liquid or second water has not been reduced sufficiently, that is, when t remains small, the target F value will not be reached, as can be seen from formula a. This will result in poor sterilization of the cleaning liquid or second water, and the liquid supply system piping 7 will become contaminated with bacteria. To avoid this, the process of lowering the temperature after the flow rate has been reduced must be observed. By observing the above process, the liquid can be replaced while maintaining sterility in the liquid supply system piping 7.

The second water in the liquid supply system piping 7 is removed by the second liquid, and after confirming that the second water has been replaced with the second liquid, the filling of the second liquid begins.

2... Filling machine 6... Return path 6a... Upstream return path 6b... Downstream return path 7... Beverage supply system piping 7a... Upstream piping section 7b... Downstream piping section 10... Temperature sensor 12... First stage heating section 13... Second stage heating section 14... Holding tube 15... First stage cooling section 16... Second stage cooling section 18... Continuous liquid sterilization device 20... Cleaning liquid supply device 21... Water supply device 23... Flow meter

Claims (5)

A liquid replacement method for a continuous liquid sterilization device that sterilizes a liquid by heating the liquid from the outside while the liquid is flowing, comprising:
Sterilization by the continuous liquid sterilization apparatus is performed by setting the retention time t minutes in the holding section of the continuous liquid sterilization apparatus, which is determined based on the flow rate of the liquid flowing through the continuous liquid sterilization apparatus, and the F value calculated by the following formula a from the temperature T ° C of the liquid to a target value or more,
F=t×10 ^(T-T0)/Z・・・Formula a (T0℃ and Z℃ are constants determined by the liquid.)
The first liquid is sterilized by the continuous liquid sterilization device;
A flow rate of the cleaning liquid is set to a flow rate greater than the flow rate of the first liquid, the retention time is calculated based on the flow rate of the cleaning liquid, T°C is calculated from the calculated retention time and the target value of the F value using formula a, and the set temperature of the continuous liquid sterilization device through which the cleaning liquid flows is set to T°C or higher, and then the flow rate of the cleaning liquid is set to the greater flow rate;
The cleaning liquid is sterilized by the continuous liquid sterilization device while flowing,
A liquid replacement method for a continuous liquid sterilization apparatus, comprising: cleaning the inside of the continuous liquid sterilization apparatus with the cleaning liquid; and then flowing a second liquid at a flow rate less than the flow rate of the cleaning liquid through the continuous liquid sterilization apparatus while sterilizing the second liquid under sterilization conditions equivalent to or lower than the sterilization conditions of the first liquid, thereby replacing the cleaning liquid with the second liquid. The liquid replacement method for the continuous liquid sterilization apparatus according to claim 1,
A liquid replacement method for a continuous liquid sterilization apparatus, comprising the steps of: cleaning the inside of the continuous liquid sterilization apparatus with the cleaning liquid; setting the flow rate of the cleaning liquid to a flow rate less than the flow rate of the cleaning liquid; and then lowering the temperature of the continuous liquid sterilization apparatus to the sterilization temperature of the second liquid. The liquid replacement method for the continuous liquid sterilization apparatus according to claim 1 or 2,
The liquid exchange method of the continuous liquid sterilization apparatus, wherein the flow rate is the flow rate of the holding section, and the temperature is the temperature at an end of the holding section. The liquid replacement method for the continuous liquid sterilization apparatus according to claim 1 or 2,
The liquid exchange method of the continuous liquid sterilization apparatus, comprising exchanging the first liquid with first water, and then exchanging the first water with the cleaning liquid. The liquid replacement method for the continuous liquid sterilization apparatus according to claim 1 or 2,
A liquid exchanging method for a continuous liquid sterilization apparatus, comprising exchanging the cleaning liquid with second water, and then exchanging the second water with the second liquid.

Images