JPH0653149B2 - Vacuum low temperature steam heat sterilization method and its sterilizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Field of Industrial Application) The present invention is a vacuum low temperature steam heat sterilization used for low temperature sterilization treatment of drugs and the like in pharmaceutical companies, medical institutions, and various laboratories. Method and its sterilization apparatus.

(Prior Art) Conventionally, for example, drugs such as vitamins which are destroyed or decomposed by high heat in preparations such as injectables need to be heat sterilized at a low temperature of 100 ° C. or lower after filling in ampoules or vials. This low-temperature heat sterilization method includes a circulating steam sterilization method in which the inside of the sterilizer is heated to atmospheric pressure and heating, or a hot bath sterilization in which water is heated to a sterilization temperature and the material to be sterilized is immersed in the hot water for sterilization. There is a law.

(Problems to be Solved by the Invention) However, in the conventional low temperature heat sterilization method such as the above-mentioned circulating steam sterilization method and hot bath sterilization method, the temperature distribution is non-uniform, and the GMP and validation currently practiced. However, there is an urgent need to solve the problem of the low temperature heat sterilization method.

The present invention has been made in view of the above circumstances, and has a second boiling point of water.
As shown in the figure, it changes depending on the atmospheric pressure, and at atmospheric pressure it boils at a temperature of 100 ° C to become water vapor, but when reducing the pressure below atmospheric pressure, the boiling point of water becomes lower than 100 ° C, and sterilization is performed. By introducing water vapor while maintaining a reduced pressure in the vessel at a vacuum degree that matches the low temperature sterilization temperature of 100 ° C or less,
A low-temperature steam heating sterilization method capable of performing a low-temperature steam heat sterilization of an object to be sterilized while maintaining a uniform temperature distribution in the sterilizer, and exhibiting excellent sterilization performance that can sufficiently comply with GMP and validation regulations, and a method thereof. It is an object to provide a sterilizer.

[Structure of Invention]

(Means for Solving the Problems) In the vacuum low-temperature steam heating sterilization method of the first invention, in order to achieve the above-mentioned object, an object to be sterilized is housed in a sterilizer and hermetically sealed,
In this state, the inside of the sterilizer is depressurized to a vacuum degree corresponding to the low temperature sterilization temperature of saturated steam of 100 ° C. or less, and steam is introduced while maintaining this vacuum degree to sterilize the object to be sterilized by low temperature steam heating. And

In order to achieve the above-mentioned object, the vacuum low-temperature steam heating sterilizer of the second invention provides a sterilizer for accommodating an object to be sterilized and a low-temperature sterilization temperature of saturated steam of 100 ° C. or less preset in the sterilizer. The steam supply means for supplying steam while controlling to maintain the state and the inside of the sterilizer using a vacuum pump
It is characterized in that it is provided with a vacuum evacuation means for maintaining a reduced pressure at a degree of vacuum suitable for the low temperature sterilization temperature of saturated steam below ℃, and a drainage means for discharging the condensed water in the sterilizer using a steam trap.

As a vacuum exhaust means of the vacuum low-temperature steam heating sterilizer of the invention, a vacuum tank which is vacuum-sucked by a vacuum pump through a cold trap is provided, and a pressure control valve is provided by a differential pressure between the vacuum tank and the sterilizer. The inside of the sterilizer is depressurized and maintained at a vacuum degree corresponding to the low temperature sterilization temperature of saturated steam of 100 ° C. or less, and the condensed water in the sterilizer is drained by the pressure difference between the vacuum tank and the sterilizer. It is desirable that the condensed water in the sterilizer is allowed to flow out to the vacuum tank side via the steam trap of the means.

(Operation) In the vacuum low-temperature steam heating sterilization method of the present invention having the above-described configuration, the change in boiling point due to the pressure of steam is used to bring the temperature of the inside of the sterilizer containing the object to be sterilized to the low-temperature sterilization temperature of saturated steam of 100 ° C or less. Since steam is introduced while maintaining a reduced pressure at a suitable degree of vacuum, the steam fills the sterilizer in a saturated state at a low temperature, and the object to be sterilized can be heat-sterilized by low-temperature steam with a uniform temperature distribution. It is possible to exhibit excellent sterilization performance that can be sufficiently adapted to the regulation of the station.

In the vacuum low-temperature steam heating sterilization apparatus of the present invention having the above-described configuration, a sterilizer for accommodating an object to be sterilized and steam controlled while maintaining a low-temperature sterilization temperature of saturated steam of 100 ° C. or less preset in the sterilizer Means for supplying steam, a vacuum exhaust means for maintaining a reduced pressure in the sterilizer using a vacuum pump to a vacuum degree corresponding to the low temperature sterilization temperature of the saturated steam of 100 ° C. or less, and a steam trap for condensed water in the sterilizer. By using this sterilization device, it is possible to execute the excellent vacuum low-temperature steam heating sterilization method since it is equipped with a drainage means for discharging using.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a schematic configuration diagram showing a flow sheet of a vacuum low temperature steam heating sterilizer of the present invention.

First, reference numeral 1 in the figure is a sterilizer in which an object A to be sterilized is stored, and is a closed container having an openable / closable lid 1a. The sterilizer 1 is provided with a safety valve 2, a pressure gauge 3, a temperature controller 4, and a sterilizer internal pressure detector 5. Further, the sterilizer 1 is provided with an air supply valve 6 and an air filter 7 for recompression, so that the outside air can be cleaned and introduced into the sterilizer 1 at the end of sterilization to recompress to atmospheric pressure.

In the figure, 10 is a steam supply system pipe connected to the side of the sterilizer 1. The steam supply system pipe 10 is connected to a steam supply source that generates steam of 100 ° C. or higher, and a steam pressure reducing valve 11 and a steam filter 1 are provided in the supply steam system pipe 10.
Two are provided. Further, a steam supply control valve 13 is provided between the steam filter 12 and the sterilizer 1. This steam supply control valve 13 is interlocked with the temperature controller 4 of the sterilizer 1, and when the temperature inside the sterilizer 1 is below the established temperature range for low temperature sterilization of 100 ° C. or less, it is opened to introduce steam, When the temperature is higher than the set temperature range, it is automatically closed to stop the introduction of water vapor.

In the figure, reference numeral 20 denotes a vacuum exhaust system pipe connected to the upper part of the sterilizer 1 and provided in the vacuum exhaust system pipe 20 in order from the sterilizer 1 side to the sterilizer internal pressure control valve 21 and the vacuum tank 2.
2, tank pressure control valve 23, cold trap 24,
A vacuum pump 25 is provided.

The sterilizer internal pressure control valve 21 works in conjunction with the sterilizer internal pressure detector 5, and when the atmospheric pressure in the sterilizer 1 is above a set atmospheric pressure (vacuum degree corresponding to the low temperature sterilization temperature of saturated steam of 100 ° C. or less) range. Is opened to allow suction and exhaust to the vacuum tank 22 side, and when the pressure is within the set atmospheric pressure range, the operation is automatically closed to stop the exhaust.

The vacuum tank 22 always maintains a vacuum state, and the vapor in the sterilizer 1 is forcibly sucked out by the differential pressure via the sterilizer internal pressure control valve 21. For this purpose, the vacuum tank 22 is provided with a tank internal pressure detector 26, and the tank internal pressure control valve 23 is automatically opened / closed in conjunction with the tank internal pressure detector 26 to cold the inside of the vacuum tank 22. Through the trap 24, the vacuum pump 25 constantly maintains a vacuum state in which the pressure inside the sterilizer 1 is reduced to a predetermined atmospheric pressure or less.

The vacuum pump 25 has a vacuum ultimate pressure of about -600 to -700 m.
It is a sealed water rotary vacuum pump of about mHg, and has a sealed water supply valve 25a and a vacuum inlet three-way valve 25b which is linked to the tank internal pressure detector 26 on the cold trap 24 side. In addition to the sealed water-type rotary vacuum pump 25, although not shown, the ultimate pressure of the vacuum is about -45.
A rotary type booster pump of about 0 mmHg or an oil rotary pump of about -1 × 10 ^-2 to -1 × 10 ^-3 mmHg of ultimate pressure may be used (the pressure unit is based on atmospheric pressure). .

The cold trap 24 is a kind of condenser, and has a coil-shaped condensing pipe 24a for heat exchange therein, to which cooling water such as ordinary city water or well water is supplied from a water supply source through a water supply valve 27. Will be conducted. This serves as a water trap for cooling the water vapor in the exhaust gas sucked out from the sterilizer 1 through the vacuum tank 22 and condensing and collecting it so as to cause dew condensation on the surface of the condensing pipe 24a. Is sent to the vacuum pump 25 side so that the function of the vacuum pump 25 can be fully exerted.

That is, most of the exhaust from the sterilizer 1 during steam heating is water vapor, which has water and heat, and when this is directly exhausted from the vacuum tank 22 by the sealed rotary vacuum pump 25, the vacuum pump The sealing water of No. 25 for sealing is heated and its temperature rises, and the ultimate vacuum is deteriorated. As a result, the predetermined vacuum degree pressure of the vacuum tank 22 cannot be maintained, the balance of the internal pressure of the sterilizer 1 is disturbed, and finally low temperature sterilization cannot be performed. Even if it could be done, the temperature distribution would be poor, and it would cause the destruction or deterioration of the sterilized object A at an abnormally high temperature. The cold trap 24 is provided in order to fully exhibit the function of the water seal rotary vacuum pump 25 without causing such an adverse effect.

By providing the cold trap 24, not only the above-described water-sealing type rotary vacuum pump 25, but also when using a rotary booster pump or an oil rotary pump as a vacuum pump, lubrication in those pumps The adverse effect of mixing steam or oil with the sealing oil is eliminated, and the function can be fully exerted.

The vacuum tank 22 and the cold trap 24 are provided with air supply valves 30 and 31 for introducing outside air to restore the atmospheric pressure when the sterilization is completed.

Further, reference numeral 40 in the figure is a drainage pipe connected to the bottom portion of the sterilizer 1 for discharging condensed water (drain) in the sterilizer 1, and the drainage pipe 40 is provided with a drain valve 41 and a steam trap 42 on the way. In addition, a bypass drain valve 43 is provided, and is further connected to the vacuum tank 22 via a drain cooler 44. Condensed water generated when the object A to be sterilized is steam-heated in the sterilizer 1 is passed through the steam trap 42 and the drain cooler 44 by the pressure difference between the sterilizer 1 and the vacuum tank 22. It is configured to be sucked out to the 22 side.

That is, the steam trap 42 required for discharging the condensed water from the sterilizer 1 cannot discharge the condensed water unless there is a pressure difference before and after this. The minimum value of the operating differential pressure P of the steam trap 42 is usually 0.3 kg / (228 mmH
g) or higher. Therefore, for example, when the low temperature sterilization temperature (boiling point of steam) is set to 80 ° C., the degree of vacuum P ₁ in the sterilizer 1 corresponding to this is −404.
Since it is maintained at 7 mmHg, the degree of vacuum P ₂ in the vacuum tank 22 is set and maintained at P ₂ <P ₁ + P = − (404.7 +228) mmHg P ₂ <−632.7 mmHg. Condensed water in the sterilizer 1 is sucked out to the vacuum tank 22 side through the steam trap 42 and the drain cooler 44 with a pressure difference from the sterilizer 1.

That is, the vacuum tank 22 has a pressure difference with the sterilizer 1,
As described above, the sterilizer 1 has both the functions of maintaining the degree of vacuum corresponding to the low temperature sterilization temperature of saturated steam of 100 ° C. or less and discharging the condensed water in the sterilizer 1.

The drain cooler 44 is supplied with cooling water from the water supply source through a water supply valve 45 to cool the condensed water coming from the sterilizer 1 through the steam trap 42 into the vacuum tank 22. It reduces the invasion of heat. That is, the vacuum tank 22 needs to be maintained at a vacuum degree of −632.7 mmHg or less so as to have a pressure difference of a predetermined value or more with the inside of the sterilizer 1 as described above. If the temperature inside the vacuum tank 22 rises above 56 ° C. (see FIG. 2), the condensed water received in the vacuum tank 22 evaporates, so that the function of the vacuum pump 25 is likely to be impaired. Therefore, the condensed water is cooled by the drain cooler 44 to prevent heat from entering the vacuum tank 22 as much as possible to reduce evaporation, and the cold trap 24 is provided as described above so that the function of the vacuum pump 25 is sufficiently achieved. By making the best use, the predetermined vacuum degree in the vacuum tank 22 is maintained.

The cooling waste water of the drain cooler 44 is discharged through a drain pipe 46. Further, the drain tank 46 is connected to the vacuum tank 22.
And the condensed water in the cold trap 24 is the drain valve 4 respectively.
The check drain 49 also discharges the cooling wastewater discharged through the condenser pipes 24a of the cold trap 24 while being discharged through 7, 48.
It is designed to be drained through.

Then, a vacuum low temperature steam heating sterilization method using the apparatus having the above-mentioned configuration will be described. As shown in FIG. 2, water boils at 100 ° C. above atmospheric pressure, and the temperature of water does not rise even if heat is further applied. Conversely, when water is placed in a closed container and the container is evacuated and decompressed, the boiling point of water falls, and the degree of vacuum is, for example, -40.
At 4.7 mmHg, water vaporizes and exists as water vapor at 80 ° C. Similarly, at a vacuum degree of -610.6 mmHg, water vaporizes and exists as water vapor at 60 ° C. As the pressure is reduced in this way, the boiling point of water changes and the water comes to exist as liquid vapor to vapor as vapor at low temperature. The vacuum low temperature steam heat sterilization method of the present invention utilizes this characteristic to perform heat sterilization with low temperature (100 ° C.) steam.

For this reason, steam is introduced into the sterilizer 1 to sterilize the object A to be sterilized while controlling the pressure inside the sterilizer 1 to a pressure corresponding to the degree of vacuum at the low temperature sterilization temperature.

For example, when the low temperature sterilization temperature is set to 80 ° C. for sterilization, the sterilizer 1 containing the object A to be sterilized is sealed and the inside is maintained at a pressure (−404,7 mmHg) corresponding to the vacuum degree of 80 ° C. Therefore, the sterilizer internal pressure detector 5 is set, and the sterilizer internal pressure control valve 21 of the vacuum evacuation system pipe 20 is automatically opened / closed by this signal. In addition, the pressure control valve 21 in the sterilizer causes the vacuum tank 22 to maintain a pressure commensurate with the vacuum degree of 80 ° C. in the sterilizer 1 by the pressure difference between the vacuum tank 22 and the sterilizer 1, and the condensed water in the sterilizer 1 Steam trap 4
The internal pressure P ₂ of the vacuum tank 22 is set to P ₂ <P ₁ + P = −63 so as to have both the functions of the discharge receiving via
The tank internal pressure detector 26 is set to a state of 2.7 mmHg, and the tank internal pressure control valve 23 is automatically controlled to be opened and closed by this signal.

While operating the vacuum pump 25 in such a state,
Water is supplied from a water supply source through the water supply valves 25a, 27, 45.

With this, the vacuum pressure inside the vacuum tank 22 is maintained at -632.7 mmHg by the vacuum control valve 23, and the sterilizer 1 is vacuum-sucked through the sterilizer pressure control valve 21 due to the pressure difference between the vacuum pressure and the vacuum pressure. The pressure is maintained at 404,7 mmHg. In this state, steam is introduced into the sterilizer 1 from the steam supply system pipe 10 through the steam pressure reducing valve 11 and the steam filter 12 and through the steam supply control valve 13 that is linked to the temperature regulator 4 set at 80 ° C. Go.

With the above, the inside of the sterilizer 1 is replaced with water vapor and kept at 80 ° C.,
The object A to be sterilized is subjected to vacuum low temperature steam heating sterilization.
At this time, as described above, the pressure inside the sterilizer 1 is constantly maintained at a pressure commensurate with the vacuum degree of 80 ° C. due to the pressure difference with the vacuum tank 22, and the condensed water in the sterilizer 1 is kept in the steam trap 42.
Since it is sucked into the vacuum tank 22 through the sterilizer 1,
It becomes possible to perform low temperature sterilization very effectively without causing a problem such as destruction of the object A to be sterilized or deterioration due to abnormally high heat due to imbalance of internal pressure and poor temperature distribution. .

Most of the exhaust air from the sterilizer 1 during steam heating is water vapor, which has water and heat, but does not flow from the vacuum tank 22 to the sealed water rotary vacuum pump 25 as it is. Cold trap 24 in front of it
Since the water vapor in the exhaust gas is cooled and condensed and collected, and only low temperature air is sent to the vacuum pump 25 side, the vacuum pump 25
Can sufficiently exert its function to maintain a predetermined vacuum degree pressure in the vacuum tank 22. As a result, the vacuum tank 22 can sufficiently perform the above-mentioned function and the low temperature sterilization in the sterilizer 1 can be performed more reliably.

〔The invention's effect〕

Since the vacuum low-temperature steam heat sterilization method of the present invention is as described above, steam can be introduced while maintaining a reduced pressure in the sterilizer at a vacuum degree that matches the low-temperature sterilization temperature of saturated steam of 100 ° C. or less. The object to be sterilized can be sterilized by low temperature steam heating while maintaining a uniform temperature distribution, and excellent sterilization performance can be exerted which can sufficiently comply with regulations of GMP and validation.

Since the vacuum low temperature steam heating sterilization apparatus of the present invention is configured as described above, it is very effective in executing the low temperature sterilization method.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a low-temperature steam heating sterilizer showing an embodiment of the present invention, and FIG. 2 is a characteristic diagram of change of boiling point temperature by atmospheric pressure of water. A ... Object to be sterilized, 1 ... Sterilizer, 10 ... Steam supply means,
20 ... Evacuation means, 21 ... Pressure control valve, 22 ...
Vacuum tank, 24 ... Cold trap, 25 ... Vacuum pump, 40 ... Drainage means, 42 ... Steam trap.

Claims (3)

[Claims] 1. An object to be sterilized is housed in a sterilizer and hermetically sealed. In this state, the inside of the sterilizer is depressurized to a vacuum degree corresponding to a low temperature sterilization temperature of saturated steam of 100 ° C. or less, and this vacuum degree is maintained. While sterilizing the object to be sterilized by low-temperature steam heating while introducing steam, a vacuum low-temperature steam heating sterilization method is characterized. 2. A sterilizer for accommodating an object to be sterilized, a steam supply means for supplying steam while controlling a condition in which a preset low temperature sterilization temperature of saturated steam of 100 ° C. or less is maintained in the sterilizer, and sterilization. A vacuum exhaust means for maintaining a reduced pressure inside the sterilizer to a vacuum degree corresponding to the low temperature sterilization temperature of the saturated steam of 100 ° C. or less, and a drainage means for discharging the condensed water in the sterilizer using a steam trap. A vacuum low-temperature steam heating sterilizer characterized by being provided. 3. The vacuum low-temperature steam heating sterilization apparatus according to claim 1, further comprising a vacuum tank, which is vacuum-evacuated by a vacuum pump via a cold trap, as vacuum evacuation means.
The pressure difference between the vacuum tank and the sterilizer causes the pressure inside the sterilizer to be reduced through the pressure control valve to maintain the vacuum at a temperature corresponding to the low temperature sterilization temperature of saturated steam of 100 ° C. or less. Vacuum low temperature steam characterized in that the condensed water in the sterilizer is made to flow out to the vacuum tank side through the steam trap of the draining means by the differential pressure of the degree of vacuum with the inside of the sterilizer. Heat sterilizer.