JP2002081611A - Steam generator for sterilizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the quantity of a non-condensable gas contained in the steam supplied to a sterilizer. SOLUTION: A steam generator 1 which generates the steam supplied to the sterilizer 12 is provided with a deaerating means 14 on a feed water line 7 connected to the generator 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam generator for a sterilizer for generating steam to be supplied to a sterilizer.

[0002]

2. Description of the Related Art Sterilization steam supplied to a steam sterilizer is:
It is necessary to maintain a predetermined quality in order to prevent sterilization defects. For example, the European standard EN285 specifies that the dryness is 0.95 or more and the non-condensable gas concentration is less than 3.5% (volume ratio). However, the concentration of the non-condensable gas has not been sufficiently controlled so far, and high-quality sterilizing steam has been demanded. If steam containing a large amount of non-condensable gas is used as steam for sterilization, even if the steam pressure is maintained at a predetermined value, the temperature of the object to be sterilized does not rise sufficiently, and sterilization failure may occur.

[0003]

The problem to be solved by the present invention is to reduce the amount of non-condensable gas contained in the steam supplied to the sterilizer.

[0004]

Means for Solving the Problems The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is a steam generating apparatus for generating steam to be supplied to a sterilizer. The water supply line to the generator is provided with deaeration means.

[0005]

Next, an embodiment of the present invention will be described. The steam generator according to the present invention generates steam to be supplied to a sterilizer, and generates pure steam by heating pure water or soft water. The water supply line to the steam generator is provided with a pure water device or a soft water device, and is provided with a deaerator for removing dissolved gas in the feed water. That is, the amount of non-condensable gas in the sterilizing steam supplied to the sterilizer can be significantly reduced by degassing the water supply to the steam generator.

The deaeration means has the following configuration. In the case where a reboiler using steam as a heating source is used as the steam generator, dewatering is performed by heating water supplied to the steam generator using the steam for heating the reboiler. For example, a heat exchanger for exchanging heat between the heating steam and the feedwater is provided. Therefore, according to this configuration, steam as a heating source to be supplied to the steam generating device can also be used as a heating source of the deaerator. Further, depending on the implementation, a configuration may be employed in which the heating steam is directly jetted into the water supply.

[0007] The degassing means may perform degassing processing by heating water supplied to the steam generating device with steam generated by the steam generating device.
That is, the clean steam generated by the steam generator is jetted directly into the feed water to heat the feed water. Therefore, according to this configuration, since clean steam is used, impurities do not enter the feedwater.
In addition, the degassing means can be constituted only by a pipe for guiding clean steam to the water supply and an on-off valve provided on this pipe, so that a simple structure can be obtained. Further, depending on the implementation, a configuration may be adopted in which a heat exchanger for exchanging heat between the clean steam and the feedwater is provided.

Further, these deaeration means are of the heat deaeration type using steam as a heating source, but may be of a configuration using an electric heater as a heating source depending on the implementation.

Further, as the degassing means, a vacuum degassing type can be used in addition to a heating degassing type. As a vacuum deaeration type deaeration means, there are a membrane deaerator and a deaeration tower. Since these deaeration means can perform the deaeration process at normal temperature, the working environment is safe.

[0010] As described above, according to the above configuration, the amount of non-condensable gas contained in the sterilizing steam supplied to the sterilizer is greatly reduced by degassing the water supply to the steam generator. Can be reduced. Therefore, steam sufficiently satisfying the reference value (non-condensable gas concentration is less than 3.5% (volume ratio)) stipulated in European Standard EN285 can be supplied as sterilizing steam. Insufficient sterilization due to gas contamination can be reliably prevented.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

First, the first embodiment shown in FIG. 1 will be described. As the steam generator 1 according to the present invention, a reboiler using steam as a heating source is used, and pure water is heated by the heating steam to generate clean steam. That is, the main body of the steam generator 1 includes an inner pipe 2 and an outer pipe 3, supplies pure water into the inner pipe 2, and supplies heating steam between the inner pipe 2 and the outer pipe 3. The pure water is supplied and heated from outside the inner tube 2.

Here, a heating steam supply line 4 is connected to the upper side of the outer tube 3, and steam for general equipment is supplied as heating steam through the heating steam supply line 4. It has become. The steam for general equipment is generated by another boiler (not shown) and is shared with other equipment such as a heating equipment. On the other hand, a drain discharge line 5 is connected to a lower side portion of the outer pipe 3, and a first steam trap 6 is provided in the drain discharge line 5.

A water supply line 7 is connected to the lower end of the inner pipe 2. The water supply line 7 is connected to a water supply tank 8, a water supply pump 9 and a check valve 10 in order from the upstream side.
Is provided. On the other hand, a steam supply line for sterilization 11 is connected to an upper end of the inner tube 2, and a downstream end of the steam supply line 11 for sterilization is connected to a sterilizer 12. The sterilization steam supply line 11 is provided with a first steam valve 13 for controlling the supply of the sterilization steam. The steam generator 1 is provided integrally with or close to the sterilizer 12.

Further, the water supply tank 8 is provided with a deaeration means 14 for removing dissolved gas in the water supply. In the first embodiment, as the degassing means 14, a coiled heat exchanger 15 to which the steam for general equipment is supplied is used.
Is provided. A steam supply line 16 branched from the heating steam supply line 4 is connected to an upstream end of the heat exchanger 15, while a second steam trap 17 is provided at a downstream end. The discharge line 18 is connected. The water level in the water supply tank 8 is maintained at a predetermined water level by water level control means (not shown) such as a ball tap mechanism.
The whole 5 is always submerged in the water supply in the water supply tank 8.

The steam supply line 16 is provided with a second steam valve 19, and the water supply tank 8 is provided with a temperature sensor 20 for detecting the temperature of water supply.
The second steam valve 19 and the temperature sensor 20 are connected to a controller 22 via signal lines 21 and 21, and the opening and closing of the second steam valve 19 is controlled based on the temperature detected from the temperature sensor 20. It has become so. Therefore, by controlling the opening and closing of the second steam valve 19, the amount of steam supply to the heat exchanger 15 is controlled so that the temperature of the water supply in the water supply tank 8 is heated to a predetermined temperature and maintained. ing. For example, heating to 60 ° C. can reduce the amount of dissolved gas in feed water by about 45%.

As described above, according to the configuration of the first embodiment, the supply water is heated and deaerated by the deaeration means 14 so as to be included in the sterilizing steam supplied to the sterilizer 12. The amount of non-condensable gas can be significantly reduced. Therefore, as steam for sterilization, European standard EN2
85 (a non-condensable gas concentration of 3.
(Less than 5% (volume ratio)) can be supplied, and sterilization failure due to mixing of non-condensable gas can be reliably prevented. Further, according to the configuration of the first embodiment, steam as a heating source to be supplied to the steam generator 1 can be used also as a heating source of the degassing means 14, and it is necessary to provide a new heating source. There is no.

In the first embodiment, steam for general equipment is directly supplied to the heat exchanger 15, but in addition, the drain discharge line 5 is connected to the heat exchanger 15. Alternatively, a configuration in which the steam for general equipment is condensed to form a drain may be supplied to the heat exchanger 15.

Next, a second embodiment shown in FIG. 2 will be described. Here, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted. Now, in the second embodiment, the deaeration means 1
As 4, clean steam generated by the steam generator 1 is directly jetted into the water supply in the water supply tank 8. That is, the sterilizing steam supply line 11
In FIG. 1, a steam ejection line 23 branches from the upstream side of the first steam valve 13, and a distal end opening (symbol is omitted) of the steam ejection line 23 is disposed in the water supply in the water supply tank 8. The steam ejection line 23 is provided with the second steam valve 19.

Therefore, by controlling the opening and closing of the second steam valve 19 based on the temperature detected by the temperature sensor 20, the amount of steam spouted into the water in the water tank 8 is controlled. The temperature of the supply water in the chamber 8 is heated to a predetermined temperature (for example, 70 ° C.) to perform the deaeration process.

As described above, according to the configuration of the second embodiment, as in the first embodiment, the supply water is heated and deaerated by the deaeration means 14, whereby the sterilizer 1 is removed.
2, the amount of non-condensable gas contained in the steam for sterilization supplied to 2 can be significantly reduced. Therefore, steam sufficiently satisfying the reference value (non-condensable gas concentration is less than 3.5% (volume ratio)) stipulated in European Standard EN285 can be supplied as sterilizing steam. Insufficient sterilization due to gas contamination can be reliably prevented. Further, according to the configuration of the second embodiment, since clean steam is used, no impurities are mixed into the feedwater. Then, the deaeration means 14 is connected to the steam
3 and the second steam valve 19 only, and a simple configuration can be achieved.

Next, a third embodiment shown in FIG. 3 will be described. Also in this case, the same reference numerals are given to the same constituent members as those in each of the above embodiments, and the detailed description is omitted. In FIG. 3, illustration of the sterilizer 12 and the first steam valve 13 is omitted. In the third embodiment, as the deaerator 14, a membrane deaerator 24 is provided in the water supply line 7 upstream of the water supply tank 8. This membrane type degassing device 24 is a degassing membrane module 2 having a large number of hollow fiber membranes (not shown).
5, a vacuum suction line 27 provided with a vacuum pump 26 is connected to the degassing membrane module 25.

Accordingly, by evacuating the outside of each of the hollow fiber membranes and supplying water through each of the hollow fiber membranes, the dissolved gas in the feed water is extracted through each of the hollow fiber membranes, and the gas is extracted to the outside. It is designed to discharge.

As described above, according to the configuration of the third embodiment, the feed water is degassed by the membrane type deaerator 24, so that the non-steam contained in the sterilizing steam supplied to the sterilizer 12 is processed. The amount of condensable gas can be greatly reduced. Therefore, steam sufficiently satisfying the reference value (non-condensable gas concentration is less than 3.5% (volume ratio)) stipulated in European Standard EN285 can be supplied as sterilizing steam. Insufficient sterilization due to gas contamination can be reliably prevented.

Next, a fourth embodiment shown in FIG. 4 will be described. Also in this case, the same reference numerals are given to the same constituent members as those in each of the above embodiments, and the detailed description is omitted. Also in FIG. 4, the illustration of the sterilizer 12 and the first steam valve 13 is omitted. Now, in the fourth embodiment, the deaeration means 14
Is provided on the upstream side of the water supply tank 8 in the water supply line 7. The degassing tower 28 includes a container 29, and a spray nozzle 30 is provided in an upper part of the container 29. The vacuum suction line 27 provided with the vacuum pump 26 is connected to the container 29. Further, between the container 29 and the water supply tank 8, a water supply pump 31 that sends degassed water to the water supply tank 8 is provided.

Therefore, by evacuating the inside of the container 29 and spraying water from the spray nozzle 30, dissolved gas is removed from the atomized water and discharged to the outside.

As described above, according to the configuration of the fourth embodiment, the deaeration tower 28 deaerates the water supply, thereby providing the non-condensable water contained in the sterilizing steam supplied to the sterilizer 12. The amount of gas can be significantly reduced. Therefore, steam sufficiently satisfying the reference value (non-condensable gas concentration is less than 3.5% (volume ratio)) stipulated in European Standard EN285 can be supplied as sterilizing steam. Insufficient sterilization due to gas contamination can be reliably prevented.

According to the third embodiment and the fourth embodiment, the deaeration can be performed at room temperature.
The working environment is safe.

[0029]

According to the present invention, the amount of non-condensable gas contained in the steam for sterilization supplied to the sterilizer can be greatly reduced. Therefore, it is possible to reliably prevent sterilization failure due to the mixing of the non-condensable gas.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a first embodiment of the present invention.

FIG. 2 is an explanatory view showing a second embodiment of the present invention.

FIG. 3 is an explanatory view showing a third embodiment of the present invention.

FIG. 4 is an explanatory view showing a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steam generator 7 Water supply line 12 Sterilizer 14 Deaerator 24 Membrane deaerator 28 Deaerator

Claims (1)

[Claims] 1. A steam generator for a sterilizer, wherein a steam generator 1 for generating steam to be supplied to a sterilizer 12 is provided with a deaerator 14 in a water supply line 7 to the steam generator 1.