JP7509334B1 - Cleaning device and cleaning method - Google Patents

Abstract

The cleaning device (100) includes an additive transport unit (8) that transports an additive in a non-supercritical state between the heating unit (4) and the cleaning tank (1) in a supercritical fluid flow path (2a) through which the supercritical fluid flows, and a control unit (6) that controls the additive transport unit (8) so as to transport the additive when the supercritical fluid transport unit (3) transports the supercritical fluid. This eliminates the need to heat the additive together with the supercritical fluid raw material, improving energy efficiency during heating. In addition, when an additive that is deactivated by heating is used, the additive can be prevented from being deactivated by heating. Therefore, contaminants on the object to be cleaned can be removed efficiently.

Description

The present disclosure relates to a cleaning apparatus and a cleaning method.

Supercritical fluids have intermediate viscosities, diffusion coefficients, densities, and dissolving powers between gases and liquids, and are characterized by their ease of penetrating micromechanical structures and high solubility for hydrophobic substances. Because of these advantages, supercritical fluids are used as solvents in cleaning equipment. Furthermore, single-component supercritical fluids are unable to clean hydrophilic contaminants and proteinaceous contaminants. Therefore, when the object being cleaned contains a large amount of at least one of hydrophilic contaminants and proteinaceous contaminants, it is necessary to use additives appropriate for each contaminant.

For example, Patent Document 1 describes a cleaning device that cleans an object to be cleaned with carbon dioxide in a supercritical or liquid state. It also describes a configuration in which, when an additive is used to remove at least one of water-soluble contaminants and proteinaceous contaminants, a pump or the like is added to the cleaning system for mixing the additive into the carbon dioxide supply pipe.

JP 2010-136860 A

However, in the invention described in Patent Document 1, the heating of the additive when it is used is not taken into consideration, and contaminants may not be removed efficiently. In the invention described in Patent Document 1, the pressure and temperature of the cleaning tank are adjusted by a supply pump and a cleaning tank temperature regulator so that the supplied liquid carbon dioxide becomes supercritical carbon dioxide at a pressure and temperature suitable for cleaning the object to be cleaned. In this case, for example, if a proteolytic enzyme is used as an additive to remove proteinaceous contaminants, the temperature in the cleaning tank may exceed the enzyme deactivation temperature, and the enzyme may be deactivated. In addition, for example, if water is used as an additive to remove water-soluble contaminants, the specific heat of water is larger than that of carbon dioxide, so the energy efficiency of heating the cleaning tank decreases.

The present disclosure has been made to solve the above-mentioned problems, and aims to provide a cleaning device and cleaning method that can efficiently remove contaminants from the object to be cleaned by preventing the additive from being heated by the heating unit.

The cleaning apparatus according to the present disclosure is characterized by comprising: a pressure-resistant cleaning tank in which an object to be cleaned is accommodated; a supercritical fluid raw material supply unit for supplying a supercritical fluid raw material; a supercritical fluid flow path connecting the cleaning tank and the supercritical fluid raw material supply unit and through which the supercritical fluid raw material flows; a supercritical fluid transport unit for pressurizing the supercritical fluid raw material within the supercritical fluid flow path and transporting the supercritical fluid raw material to the cleaning tank; a heating unit, disposed between the supercritical fluid raw material supply unit and the cleaning tank, for heating the supercritical fluid raw material to form a supercritical fluid; an additive supply unit, comprising at least one component, for supplying an additive in a non-supercritical state that is not in a supercritical state; an additive flow path, connecting the space between the heating unit and the cleaning tank in the supercritical fluid flow path and the additive supply unit, through which the additive flows; an additive transport unit, provided in the additive flow path, for transporting the additive in a non-supercritical state between the heating unit and the cleaning tank within the supercritical fluid flow path; and a control unit, for controlling the additive transport unit to transport the additive when the supercritical fluid transport unit is transporting the supercritical fluid.

The cleaning method according to the present disclosure is characterized by comprising the steps of: supplying a supercritical fluid raw material from a supercritical fluid raw material supply unit to a cleaning tank containing an object to be cleaned; heating the supercritical fluid raw material to form a supercritical fluid by a heating unit disposed between the supercritical fluid raw material supply unit and the cleaning tank; and transporting an additive in a non-supercritical state between the heating unit and the cleaning tank while the supercritical fluid is being transported in a supercritical fluid flow path connecting the supercritical fluid raw material supply unit and the cleaning tank.

According to the present disclosure, the cleaning device includes an additive transport unit that transports an additive in a non-supercritical state between a heating unit and a cleaning tank within a supercritical fluid flow path through which a supercritical fluid flows. This makes it possible to provide a cleaning device and a cleaning method that can efficiently remove contaminants from an object to be cleaned.

FIG. 1 is a schematic diagram of a cleaning device according to a first embodiment. FIG. 2 is a schematic phase diagram of carbon dioxide representing the solid, liquid, gas and supercritical states. FIG. 3 shows a summary of the critical temperatures and critical pressures of representative substances that reach a supercritical state. FIG. 4 shows a summary of the enzyme inactivation temperatures of representative proteases. FIG. 5 is a schematic diagram of a cleaning device including a sterilizing agent supply unit according to the first embodiment. FIG. 6 is a flowchart showing a cleaning method using the cleaning apparatus of the first embodiment. FIG. 7 is a flow chart showing a cleaning method using the cleaning device of the first embodiment when carbon dioxide is used as the supercritical fluid and a protease is used as the additive. FIG. 8 is a flow chart showing a cleaning method using the cleaning apparatus of the first embodiment when a step of supplying a sterilizing agent for sterilizing the object to be cleaned is added.

The cleaning device 100 and cleaning method according to the embodiment will be described below with reference to the drawings. The following embodiment is merely an example, and the embodiment can be modified as appropriate. In the drawings, similar components are given the same reference numerals.

Embodiment 1.
A cleaning apparatus 100 in the first embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of the cleaning apparatus 100 in the first embodiment. The cleaning apparatus 100 includes a cleaning tank 1, a supercritical fluid raw material supply unit 2, a supercritical fluid flow path 2a through which the supercritical fluid raw material flows, a supercritical fluid transport unit 3, a heating unit 4, a discharge unit 5, a control unit 6, an additive supply unit 7, an additive transport unit 8, a pressure measurement unit 9, a temperature measurement unit 10, and a separation unit 11.

The cleaning tank 1 has a storage chamber, which is an internal space in which the object to be cleaned is stored. The cleaning tank 1 also has a cleaning tank body 1a in which the opening of the storage chamber opens as an upper opening, and a lid member 1b that is attached to the upper opening in a liquid-tight and airtight manner. The cleaning tank 1 is designed to have sufficient pressure resistance to allow a supercritical fluid to be injected at a predetermined pressure.

The objects to be cleaned are, for example, medical tools such as catheters, dialyzers, plasma filters, test tubes for blood tests, blood tubes, parts of large medical instruments, small medical devices, small medical instruments, etc. When reusing medical tools, it is necessary to thoroughly remove any attached body fluids, etc. For this reason, supercritical fluids, which easily penetrate into micromechanisms and have high solubility for hydrophobic substances, are suitable as solvents for cleaning medical tools. Furthermore, the objects to be cleaned are not limited to medical tools, and may be, for example, textile structures made of fibers such as clothing or bedding.

The cleaning device 100 may also be provided with a lid member restricting portion that restricts the lid member 1b when pressurized. This prevents the lid member 1b from slipping out of the upper opening of the cleaning tank body 1a due to the pressure of the supercritical fluid injected into the cleaning tank 1.

The lid member regulating part has a member that regulates the bottom surface of the cleaning tank 1 and the top surface of the lid member 1b so that they cannot move. The lid member regulating part is, for example, a yoke. The lid member regulating part includes a horizontal support member that supports the bottom surface of the cleaning tank 1 so that it cannot move, an upper horizontal member that regulates the lid member 1b of the cleaning tank 1 from protruding upward, and a vertical member that connects the horizontal support member and the upper horizontal member to each other.

The lid member regulating portion is provided in a position withdrawn from the cleaning tank 1 except during pressure treatment so that the lid member 1b can be removed from the cleaning tank body 1a. The lid member regulating portion may be provided on a rail so that it can be moved to a position where it regulates the lid member 1b and the cleaning tank body 1a when pressure treatment is performed.

The control unit 6 controls the heating unit 4, the exhaust unit 5, the pressure measuring unit 9, the temperature measuring unit 10 and various valves in the system. A personal computer or the like programmed with the process operations can be used as the control unit 6. The control method by the control unit 6 will be explained in the cleaning method described below.

Here, a supercritical fluid refers to a fluid that is in a region that exceeds the critical temperature and critical pressure specific to the substance. Substances that can form a supercritical fluid include, for example, carbon dioxide, nitrous oxide, ethane, and propane. FIG. 2 is a schematic state diagram of carbon dioxide, showing the solid, liquid, gas, and supercritical states. In region A in FIG. 2, carbon dioxide is a solid. In region B in FIG. 2, carbon dioxide is a liquid. In region C in FIG. 2, carbon dioxide is a gas. In region D in FIG. 2, carbon dioxide is in a supercritical state. As shown in FIG. 2, carbon dioxide becomes supercritical at a temperature higher than the critical temperature of 31°C and at a pressure higher than the critical pressure of 7.4 MPa.

Figure 3 summarizes the critical temperatures and critical pressures of typical substances that reach a supercritical state. The supercritical fluid to be used is determined appropriately depending on the level of contamination of the object to be cleaned and the type of contamination. In many cases, carbon dioxide is the preferred supercritical fluid because its critical temperature is relatively low and it has little impact on the environment when exhausted as a gas.

Supercritical fluids have intermediate viscosities, diffusion coefficients, densities, and dissolving powers between gases and liquids, and are characterized by their ease of penetrating micromechanical structures and their high solubility for hydrophobic substances. This allows supercritical fluids to dissolve contaminants in the object being cleaned. Supercritical fluids also do not oxidize, hydrolyze, deteriorate, or alter plastics. Supercritical fluids also extract a small amount of additives such as plasticizers in plastics, and can dissolve or decompose residual blood and proteins at low temperatures to remove them. Furthermore, the supercritical fluids of the above substances are not harmful to workers. In addition, because they are originally compressed gases for use, when the pressure is returned to normal pressure, the supercritical fluids become gaseous.

The supercritical fluid raw material supply unit 2 is a cylinder for supercritical fluid raw materials filled with a gas or liquid that becomes a supercritical fluid. The supercritical fluid flow path 2a through which the supercritical fluid raw material flows connects the cleaning tank 1 and the supercritical fluid raw material supply unit 2. The supercritical fluid transport unit 3 is a pressure pump for pressurizing the supercritical fluid raw material into the cleaning tank 1. The supercritical fluid transport unit 3 pressurizes the supercritical fluid raw material so that the supercritical fluid raw material becomes higher than the critical pressure. For example, when the supercritical fluid raw material is carbon dioxide, the supercritical fluid transport unit 3 pressurizes the supercritical fluid raw material so that the pressure becomes 7.4 MPa or higher, which is the critical pressure of carbon dioxide. The supercritical fluid transport unit 3 transports the supercritical fluid raw material supplied from the supercritical fluid raw material supply unit 2 to the cleaning tank 1 within the supercritical fluid flow path 2a. The supercritical fluid raw material supply unit 2 includes a supercritical fluid supply valve 2b in a supercritical fluid passage 2a, and is capable of adjusting the supply amount of the supercritical fluid raw material.

The heating unit 4 is disposed between the supercritical fluid raw material supply unit 2 and the cleaning tank 1. The heating unit 4 is equipped with a heating unit temperature measurement unit that measures the temperature of the heating unit 4. The control unit 6 inputs a temperature detection signal output by the heating unit temperature measurement unit provided in the heating unit 4. The heating unit 4 heats the supercritical fluid raw material so that the temperature becomes higher than the critical temperature of the supercritical fluid raw material. For example, when the supercritical fluid raw material is carbon dioxide, the heating unit 4 heats the supercritical fluid raw material so that the temperature becomes higher than 31°C, which is the critical temperature of carbon dioxide. The heating unit 4 is formed, for example, of an electric heater or a hot water flow pipe. In many cases, an electric heater is used for the heating unit 4.

The additive supply unit 7 supplies an additive consisting of at least one component to the cleaning tank 1. The additive flow path 7a through which the additive flows connects the area between the heating unit 4 and the cleaning tank 1 in the supercritical fluid flow path 2a to the additive supply unit 7. The additive supply unit 7 is provided with an additive supply valve 7b in the additive flow path 7a, and is capable of adjusting the amount of additive supplied. The additive is dissolved in the supercritical fluid and supplied to the cleaning tank 1. The additive is dissolved in the supercritical fluid in a non-supercritical state, which is not a supercritical state.

Here, the additives in the first embodiment are explained. A single-component supercritical fluid cannot completely wash away hydrophilic contaminants and proteinaceous contaminants. For example, when the object to be cleaned is a medical device, body fluids often adhere to the object. Therefore, it is necessary to remove the body fluids adhered to the object to be cleaned and reuse the object. However, a single-component supercritical fluid cannot completely remove hydrophilic contaminants and proteinaceous contaminants derived from body fluids. Therefore, when the object to be cleaned contains a large amount of hydrophilic contaminants or proteinaceous contaminants, it is necessary to use additives suitable for each contaminant. For example, polar substances, proteolytic enzymes, etc. are used as additives.

Polar substances are, for example, water, alcohol, etc. Examples of alcohol include methanol, ethanol, propanol, n-propanol, isopropanol, etc. Polar substances have polarity within the molecule. Hydrophilic contaminants are generally highly soluble in polar substances, so the polar substances dissolve the hydrophilic contaminants. This makes it possible to remove the hydrophilic contaminants from the object to be cleaned. The polar substances are transported to the cleaning tank 1 by dissolving in the supercritical fluid. At this time, the polar substances are supplied within a range that does not exceed their solubility in the supercritical fluid. This makes it possible to prevent the polar substances that have dissolved the contaminants from remaining in the cleaning tank 1.

Protease includes, for example, protease, amylase, lipase, cellulase, etc. In many cases, the preferred protease is protease. When protease is used as an additive, it may be added together with water. Protease acts as a catalyst to hydrolyze proteins into smaller polypeptides or amino acids. This makes it possible to remove proteinaceous contaminants from the object to be cleaned. Protease is transported to the cleaning tank 1 by dissolving in a supercritical fluid. At this time, the protease is supplied within a range that does not exceed its solubility in the supercritical fluid. This makes it possible to prevent the protease from remaining in the cleaning tank 1. FIG. 4 also shows a summary of the enzyme deactivation temperatures of representative protease. The enzyme deactivation temperature is the temperature at which the protease is irreversibly thermally denatured and deactivated. When protease is used as an additive, the control unit 6 controls the heating unit 4 so that the temperature is lower than the enzyme deactivation temperature of the protease.

The additive transport unit 8 is a pressure pump provided in the additive flow path 7a for pressurizing the additive. The additive transport unit 8 transports the additive between the heating unit 4 and the cleaning tank 1 in the supercritical fluid flow path 2a. When the heating unit 4 heats the supercritical fluid raw material with the critical temperature of the target supercritical fluid raw material as the target temperature, the temperature of the part in the supercritical fluid flow path 2a where the heating unit 4 is located is higher than the target temperature. When the additive is transported, the additive dissolves in the supercritical fluid because the supercritical fluid flows in the supercritical fluid flow path 2a. At this time, the supercritical fluid flows in the supercritical fluid flow path 2a from the heating unit 4 toward the cleaning tank 1, so the additive is transported to the cleaning tank 1 without flowing through the part in the supercritical fluid flow path 2a where the heating unit 4 is located.

The pressure measuring unit 9 employs a known means or device capable of measuring the pressure inside the cleaning tank 1 and outputting a pressure detection signal corresponding to the pressure inside the cleaning tank 1. The control unit 6 inputs the pressure detection signal output by the pressure measuring unit 9, determines the amount of supercritical fluid to be injected into the cleaning tank 1, and controls the supply amount of supercritical fluid raw material.

The temperature measuring unit 10 employs a known means or device capable of measuring the temperature inside the cleaning tank 1 and outputting a temperature detection signal corresponding to the temperature inside the cleaning tank 1. The control unit 6 inputs the temperature detection signal output from the temperature measuring unit 10.

The discharge unit 5 discharges the supercritical fluid in which the contaminants on the object to be cleaned have been dissolved from the cleaning tank 1. This makes it possible to remove the contaminants on the object to be cleaned. The discharge unit 5 is formed, for example, with a discharge unit discharge flow path 5a that communicates from the cleaning tank 1 to the outside, and a discharge unit discharge valve 5b arranged midway along the discharge unit discharge flow path 5a. The control unit 6 also controls the discharge unit 5 based on the pressure and temperature within the cleaning tank 1 so as to discharge the supercritical fluid while maintaining the supercritical state of the supercritical fluid.

The separation section 11 receives the supercritical fluid discharged from the cleaning tank 1 by the discharge section 5. The separation section 11 can depressurize the supercritical fluid until it becomes a gaseous state. At this time, the supercritical fluid and the contaminants dissolved in the supercritical fluid are separated. The contaminants separated from the supercritical fluid and turned into a solid or liquid are discharged from the separation section discharge flow path 11a that communicates with the outside from the separation section 11. A separation section discharge valve 11b is arranged in the middle of the separation section discharge flow path 11a, and the opening and closing of the separation section discharge valve 11b is controlled by the control unit 6. In addition, the supercritical fluid separated from the contaminants is exhausted from the separation section exhaust flow path 11c that communicates with the outside from the separation section 11. A separation section exhaust valve 11d is arranged in the middle of the separation section exhaust flow path 11c, and the opening and closing of the separation section exhaust valve 11d is controlled by the control unit 6.

The cleaning device 100 may further include a disinfectant supply unit 12 that supplies a disinfectant to the cleaning tank 1 for disinfecting the object to be cleaned. FIG. 5 is a schematic diagram of the cleaning device 100 including the disinfectant supply unit 12 of the first embodiment. The disinfectant is, for example, water vapor, ethylene gas, ethanol, etc. The disinfectant flow path 12a through which the disinfectant flows connects the cleaning tank 1 and the disinfectant supply unit 12. The disinfectant is transported by the disinfectant transport unit 13. The disinfectant transport unit 13 is a pressure pump provided in the disinfectant flow path 12a for pressurizing the disinfectant into the cleaning tank 1. The disinfectant transport unit 13 supplies the disinfectant to the cleaning tank 1 when the discharge unit 5 discharges the supercritical fluid in which the contaminants are dissolved from the cleaning tank 1. The disinfectant supply unit 12 includes a disinfectant supply valve 12b in the disinfectant flow path 12a, and can adjust the amount of disinfectant supplied.

Next, a description will be given of a cleaning method using the cleaning apparatus 100 in the embodiment 1. Fig. 6 is a flow chart showing the cleaning method using the cleaning apparatus 100 in the embodiment 1.
In step S101, the control unit 6 controls the supercritical fluid raw material supply unit 2 to supply the supercritical fluid raw material to the cleaning tank 1 containing the object to be cleaned. When supplying the supercritical fluid raw material, the control unit 6 controls the supercritical fluid supply valve 2b to adjust the supply amount of the supercritical fluid raw material. The control unit 6 also controls the supercritical fluid transport unit 3 to transport the supercritical fluid raw material supplied from the supercritical fluid raw material supply unit 2 to the cleaning tank 1 in the supercritical fluid flow path 2a.
In step S102, the control unit 6 controls the heating unit 4 disposed between the cleaning tank 1 and the supercritical fluid raw material supply unit 2 to heat the supercritical fluid raw material to form a supercritical fluid.
In step S103, the control unit 6 controls the additive supply unit 7 to supply the additive to the cleaning tank 1. When supplying the additive, the control unit 6 controls the additive supply valve 7b to adjust the amount of additive supplied. The control unit 6 also controls the additive transport unit 8 to transport the additive in a non-supercritical state between the heating unit 4 and the cleaning tank 1 through the additive flow path 7a when the supercritical fluid is being transported in the supercritical fluid flow path 2a connecting the cleaning tank 1 and the supercritical fluid supply unit.
In step S104, the control unit 6 controls the discharge unit 5 to discharge the supercritical fluid from the cleaning tank 1. Based on the pressure detection signal output by the pressure measurement unit 9 and the temperature detection signal output by the temperature measurement unit 10, the control unit 6 controls the discharge unit 5 to discharge the supercritical fluid from the cleaning tank 1 while maintaining the supercritical state of the supercritical fluid.

FIG. 7 is a flow chart showing a cleaning method using the cleaning device 100 in the first embodiment when carbon dioxide is used as the supercritical fluid and a protease is used as the additive.
In step S111, the control unit 6 controls the supercritical fluid raw material supply unit 2 to supply carbon dioxide in a gaseous or liquid state to the cleaning tank 1 containing the object to be cleaned.
In step S112, the control unit 6 controls the heating unit 4 disposed between the cleaning tank 1 and the supercritical fluid raw material supply unit 2 to heat the carbon dioxide in a gaseous or liquid state to form a supercritical fluid.
In step S113, the control unit 6 controls the additive transport unit 8 to transport a protease in a non-supercritical state between the heating unit 4 and the cleaning tank 1 while carbon dioxide in a supercritical state is being transported within the supercritical fluid flow path 2a connecting the cleaning tank 1 and the supercritical fluid supply unit.
In step S114, the control unit 6 controls the heating unit 4 so that the temperature of the carbon dioxide transported to the cleaning tank 1 is higher than the critical temperature of carbon dioxide and lower than the enzyme deactivation temperature, which is the temperature at which the protease is deactivated.
In step S<b>115 , the control unit 6 controls the discharge unit 5 to discharge the carbon dioxide in a supercritical fluid state from the cleaning tank 1 .

FIG. 8 is a flow chart showing a cleaning method using the cleaning device 100 in the first embodiment, in which a step of supplying a sterilizing agent for sterilizing the object to be cleaned is added.
Steps S121 to S124 are similar to steps S101 to S104, respectively.
In step S125, the control unit 6 controls the sterilizing agent supply unit 12 to supply the sterilizing agent for sterilizing the object to be cleaned to the cleaning tank 1. When supplying the sterilizing agent, the control unit 6 controls the sterilizing agent supply valve 12b to adjust the amount of the sterilizing agent supplied. The control unit 6 also controls the sterilizing agent transport unit 13 to transport the sterilizing agent supplied from the sterilizing agent supply unit 12 to the cleaning tank 1 in the sterilizing agent flow path 12a.

In this way, the cleaning device 100 in the first embodiment includes an additive transport unit 8 that transports the additive in a non-supercritical state between the heating unit 4 and the cleaning tank 1 in the supercritical fluid flow path 2a through which the supercritical fluid flows, and a control unit 6 that controls the additive transport unit 8 to transport the additive when the supercritical fluid transport unit 3 transports the supercritical fluid. With the above configuration, the additive is transported to the cleaning tank 1 without flowing through the part in the supercritical fluid flow path 2a where the heating unit 4 is located, so the additive is not heated by the heating unit 4. This eliminates the need to heat the additive together with the supercritical fluid raw material, improving energy efficiency during heating. In addition, when an additive that is deactivated by heating is used, it is possible to prevent the additive from being deactivated by heating. Therefore, it is possible to efficiently remove contaminants from the object to be cleaned.

Furthermore, the control unit 6 controls the discharge unit 5 to discharge the supercritical fluid while maintaining the supercritical state of the supercritical fluid based on the pressure and temperature in the cleaning tank 1. With the above configuration, the supercritical fluid and the contaminants dissolved in the supercritical fluid are not separated in the cleaning tank 1, so that it is possible to prevent the contaminants from re-adhering to the object to be cleaned.

The separation unit 11 also separates the supercritical fluid discharged from the cleaning tank 1 by the discharge unit 5 from the contaminants dissolved in the supercritical fluid. With the above configuration, the contaminants separated from the supercritical fluid and turned into a solid or liquid are discharged from the separation unit discharge flow path 11a that communicates with the outside from the separation unit 11, thereby preventing the contaminants from reattaching to the object to be cleaned and the equipment piping.

The additive may also be a protease. With the above configuration, proteinaceous contaminants that cannot be completely removed by a single-component supercritical fluid can be removed from the object being cleaned. This allows for efficient removal of contaminants from the object being cleaned. When a protease is used as an additive, it may be added together with water. This can promote hydrolysis of proteinaceous contaminants by the protease.

Alternatively, the additive may be a protease, and carbon dioxide, which has a relatively low critical temperature, may be used as the supercritical fluid raw material. In this case, the control unit 6 controls the heating unit 4 so that the temperature of the carbon dioxide transported to the cleaning tank 1 is higher than the critical temperature of carbon dioxide and lower than the enzyme deactivation temperature. With the above configuration, carbon dioxide can be brought to a supercritical state, and the protease can be dissolved in the supercritical carbon dioxide without being deactivated. This allows efficient removal of contaminants from the object to be cleaned.

The additive may also be a polar substance. With the above configuration, it is possible to remove hydrophilic contaminants from the object being cleaned that cannot be completely removed with a single-component supercritical fluid. This allows for efficient removal of contaminants from the object being cleaned.

In addition, the sterilizing agent supply unit 12 supplies the sterilizing agent to the cleaning tank 1 when the discharge unit 5 discharges the supercritical fluid from the cleaning tank 1. With the above configuration, the object to be cleaned can be sterilized after the contaminants on the object to be cleaned are removed by the supercritical fluid. This improves the cleaning performance of the cleaning device 100.

The cleaning method using the cleaning apparatus 100 in the first embodiment includes the steps of: supplying a supercritical fluid raw material by the supercritical fluid raw material supply unit 2; heating the supercritical fluid raw material to form a supercritical fluid by the heating unit 4 arranged between the cleaning tank 1 containing the object to be cleaned and the supercritical fluid raw material supply unit 2; transporting an additive in a non-supercritical state between the heating unit 4 and the cleaning tank 1 by the additive transport unit 8 in the supercritical fluid flow path 2a connecting the cleaning tank 1 and the supercritical fluid supply unit and through which the supercritical fluid flows; and discharging the supercritical fluid from the cleaning tank 1 by the discharge unit 5. This prevents the additive from being heated by the heating unit 4, and allows efficient removal of contaminants from the object to be cleaned.

Although the supercritical fluid separated from the contaminants has been described as being exhausted from the separation section exhaust flow path 11c that communicates with the outside from the separation section 11, this is not limited to this. In other words, the supercritical fluid may be circulated without being exhausted. When circulating the supercritical fluid without being exhausted, the separation section exhaust flow path 11c may be arranged so as to communicate between the supercritical fluid raw material supply section 2 and the heating section 4. Even in this case, the additive is not heated by the heating section 4, so the same effect of efficiently removing contaminants from the object to be cleaned is achieved.

1 cleaning tank, 1a cleaning tank body, 1b cover member, 2 supercritical fluid raw material supply section, 2a supercritical fluid flow path, 2b supercritical fluid supply valve, 3 supercritical fluid transport section, 4 heating section, 5 exhaust section, 5a exhaust section exhaust flow path, 5b exhaust section exhaust valve, 6 control section, 7 additive supply section, 7a additive flow path, 7b additive supply valve, 8 additive transport section, 9 pressure measurement section, 10 temperature measurement section, 11 separation section, 11a separation section exhaust flow path, 11b separation section exhaust valve, 11c separation section exhaust flow path, 11d separation section exhaust valve, 12 sterilizing agent supply section, 12a sterilizing agent flow path, 12b sterilizing agent supply valve, 13 sterilizing agent transport section

Claims (10)

a pressure-resistant cleaning tank in which an object to be cleaned is accommodated;
a supercritical fluid raw material supply unit that supplies a supercritical fluid raw material;
a supercritical fluid flow path connecting the cleaning tank and the supercritical fluid raw material supply unit, through which the supercritical fluid raw material flows;
a supercritical fluid transport unit that pressurizes the supercritical fluid raw material in the supercritical fluid flow path and transports the supercritical fluid raw material to the cleaning tank;
a heating unit disposed between the supercritical fluid raw material supply unit and the cleaning tank, the heating unit heating the supercritical fluid raw material to form a supercritical fluid;
An additive supply unit that supplies an additive that is composed of at least one component and is in a non-supercritical state, not in a supercritical state;
an additive flow path that connects a portion between the heating unit and the cleaning tank in the supercritical fluid flow path and the additive supply unit, and through which the additive flows;
an additive transport unit provided in the additive flow path and configured to transport the additive in a non-supercritical state between the heating unit and the cleaning tank within the supercritical fluid flow path;
a control unit that controls the additive transport unit so as to transport the additive when the supercritical fluid transport unit transports the supercritical fluid;
A cleaning device comprising: The cleaning device according to claim 1, characterized in that the additive is a proteolytic enzyme. the supercritical fluid source is carbon dioxide;
The cleaning device according to claim 2, characterized in that the control unit controls the heating unit so that the temperature of the carbon dioxide transported to the cleaning tank is higher than the critical temperature of the carbon dioxide and lower than the enzyme inactivation temperature, which is the temperature at which the protease is inactivated. The cleaning device according to claim 1, characterized in that the additive is a polar substance. a pressure measuring unit for measuring a pressure in the cleaning tank; and a temperature measuring unit for measuring a temperature in the cleaning tank.
and a discharge unit for discharging the supercritical fluid from the cleaning tank.
2. The cleaning apparatus according to claim 1, wherein the control unit controls the discharge unit to discharge the supercritical fluid while maintaining the supercritical state of the supercritical fluid based on the pressure and temperature in the cleaning tank. a discharge unit that discharges the supercritical fluid from the cleaning tank;
2. The cleaning apparatus according to claim 1, further comprising a separation unit which separates the supercritical fluid discharged from the cleaning tank by the discharge unit from contaminants dissolved in the supercritical fluid. a discharge unit that discharges the supercritical fluid from the cleaning tank;
2. The cleaning apparatus according to claim 1 , further comprising a sterilizing agent supply unit that supplies a sterilizing agent to the cleaning tank for sterilizing the object to be cleaned when the discharge unit discharges the supercritical fluid from the cleaning tank. supplying a supercritical fluid source from a supercritical fluid source supply unit to a cleaning tank containing an object to be cleaned;
a step of heating the supercritical fluid raw material to form a supercritical fluid by a heating unit disposed between the supercritical fluid raw material supply unit and the cleaning tank;
a step of transporting an additive in a non-supercritical state between the heating unit and the cleaning tank while the supercritical fluid is being transported in a supercritical fluid flow path connecting the supercritical fluid raw material supply unit and the cleaning tank;
A cleaning method comprising: the supercritical fluid source is carbon dioxide;
The additive is a protease,
9. The cleaning method according to claim 8, further comprising a step of controlling the heating unit so that the temperature of the carbon dioxide transported to the cleaning tank is higher than the critical temperature of the carbon dioxide and lower than an enzyme inactivation temperature at which the protease is inactivated. 9. The cleaning method according to claim 8, further comprising the step of supplying a germicide for sterilizing the object to be cleaned to the cleaning tank when the supercritical fluid is discharged from the cleaning tank.

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