JP2003130992A - Iodine filter performance evaluation device and its operation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an iodine filter performance evaluation device capable of executing with specific test conditions such as temperature, humidity and velocity. SOLUTION: In the iodine filter performance evaluation device and its operation method, a pre-filter and a fine particle filter (HEPA filter) are placed in a gas flow path. A gas control system is provided downstream the HEPA filter. The gas flow path is split downstream the gas control system into three systems of iodine generation system, a humidifying system and a by-pass system. Downstream each system, the three systems merge in a mixing system and is connected with further downstream test piece system as a system of gas flow path. Downstream the test piece system, a backup system is placed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for evaluating the performance of iodine filters used in nuclear facilities.

[0002]

2. Description of the Related Art Radioactive iodine released into the air at the time of an accident at a nuclear facility is in the form of iodine gas or methyl iodide, both in a gaseous state. In order to prevent it from being released into the public environment, a filter for removing this radioactive iodine, that is, an iodine filter is generally installed in the exhaust system. The iodine filter captures and removes iodine by adsorption, isotope exchange reaction, or chemical reaction, and is generally a filter filled with activated carbon with iodine attached in a form such as KI or zeolite with silver attached. . Hereinafter, these activated carbons and zeolites are simply referred to as "adsorbents". The adsorbent is exposed to the atmosphere or exhaust even in a normal time other than the time of an accident, and the trace amount of components contained in the adsorbent reduces the iodine removal performance. Therefore, it is necessary to periodically confirm that the prescribed performance is maintained, and take out a part of the used adsorbent,
I'm trying it out.

Such an iodine removal performance testing device is as shown in FIG. Although Freon is used instead of iodine in this figure, the basic structure of the device is the same. Since the iodine removal performance is affected by temperature, humidity, flow velocity, etc., it is indispensable to perform it under the test conditions such as the determined temperature, humidity, flow velocity, etc. There was a problem. (1) Since the atmosphere is used as it is, the humidity cannot be adjusted, and the humidity depends on the atmospheric conditions. (2) It takes a considerable amount of time for the amount of freon (which corresponds to iodine and is referred to as iodine hereinafter) to stabilize, but since all of the iodine generated during that period also passes through the adsorbent, Accurate evaluation was difficult. (3) The temperature of the test adsorbent is controlled by the duct 101 upstream of the adsorbent.
Since fine adjustment is difficult because it is performed by inputting it to the heater 129 wound around, and it is also affected by the environmental temperature, very skill is required. Further, since the flow velocity is low, the inside of the duct 101 is not sufficiently mixed, and the temperature near the outer wall around which the heater 129 is wound becomes high, resulting in uneven temperature. (4) In recent years, it has been reported that the lower the temperature, the lower the iodine removal efficiency, but since it does not have a cooling function and can only perform tests above atmospheric temperature, tests at low temperatures are not possible. there were.

[0004]

In view of the above problems, the present inventors can perform evaluation under test conditions such as predetermined temperature, humidity, and flow velocity, and operate with stable iodine amount. In addition to being able to do so, the inventors have earnestly studied to develop a device for evaluating the performance of an iodine filter, which can control the temperature regardless of the flow rate, has little temperature unevenness, and can control the humidity. As a result, the inventors of the present invention, regarding the gas supplied to the specimen,
After passing through the filter, the gas is once branched to perform stable iodine generation and humidification in each flow path, and the method of mixing them and supplying them to the test sample solves the above problems. I found it. The present invention has been completed from this point of view.

[0005]

That is, the present invention is as follows.
A pre-filter and a particulate filter (HEPA filter: High Efficiency Particulate Air filter) are installed in the gas flow path of the system, and the particulate filter (HEPA filter)
Is provided with a gas adjustment system, and the gas flow path is branched into three systems of an iodine generation system, a humidification system and a bypass system in the downstream of the gas adjustment system. The three systems merge again in the mixing system, and are connected to the downstream sample system as one gas flow path, and a backup system is installed downstream of the sample system. An evaluation device is provided. Here, a steam generator is installed in the humidification system,
The air and water are brought into contact with each other in a laminar flow in the steam generator to prepare high-humidity air in which water mist is not generated,
It is preferable that air is heated in consideration of the latent heat of vaporization upstream of the steam generator, and high-humidity air is heated downstream of the steam generator to prevent generation of water mist. Further, in the humidification system, two vapor generation bubble columns having a built-in demister are installed in series, and a mist separator or a HEPA filter filled with a sub-μm diameter fiber layer is provided downstream of the vapor generation bubble columns. With the provision
A mode in which a heater is provided downstream of the mist separator is also suitable. At this time, it is preferable to install, in the constant temperature chamber, from the inlet temperature measuring point of the second steam generating bubble column, which is the downstream of the steam generating bubble column, to the sample system.

In the present invention, in the mixer main body provided in the mixing system, the inlets of the humidified air from the humidifying system and the dry air from the bypass system and the outlets of the mixed air at different ends. It is arranged so that it faces the opposite direction toward the outside of the main body,
An example is a mode in which the inflow position of the gas containing iodine from the iodine generation system is provided between the inflow port and the outflow port. Further, in the iodine generation system, an iodine generation container is installed in a constant temperature bath to maintain a predetermined iodine concentration, and iodine crystals and glass wool are alternately stacked inside the iodine generation container. Thus, a preferred mode is one in which air is passed between the iodine crystals to generate gaseous iodine. At this time, it is preferable that a line that bypasses the iodine generation container is provided.

Further, in the iodine generation system,
The iodine generator is installed in a thermostatic chamber together with a part of the inflow / outflow pipe of air connected to the iodine generator, and the iodine generator is provided with an iodine generation container and iodine generation. The container preferably has a configuration in which the inside of the upper part thereof is thin and the upper part is opened. In the device of the present invention, it is preferable that bypass lines are provided in both the sample system and the backup system, respectively.

Further, according to the present invention, the dehumidified and flow-regulated gas that has passed through the pre-filter and then the HEPA filter is divided into three systems of an iodine generation system, a humidification system and a bypass system to flow down. , A method of operating an elementary filter performance evaluation device, in which the gases of the three systems are merged again in the mixed system, the gas is introduced into the sample system, and the outflowed gas is further supplied to the backup system in the downstream. To do. Here, for example, the bypass system, and, after passing the total amount of gas in the bypass line of the sample system and the bypass line of the backup system, while circulating the gas in the iodine generation system and the humidification system, Operation in which gas is circulated to the sample system and the backup system, and after a predetermined time has elapsed, gas is returned to the bypass lines of the sample system and the backup system and the bypass system to distribute the total amount of gas. There is a method. Further, it is preferable that the pressure loss of the bypass line is substantially the same as the pressure loss of the main line of the sample system or the backup system.

In the present invention, when the iodine filter performance evaluation apparatus described in any of the above is used to evaluate the iodine filter performance, the iodine collection efficiency is set to the sample system and the backup system. It can be calculated from the amount of iodine collected.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the iodine filter performance evaluation apparatus and its operating method according to the present invention will be described below with reference to the accompanying drawings. Embodiment (No. 1) FIG. 1 is a flow sheet of this embodiment, showing a basic system. In the present embodiment, the atmosphere is sucked by the blower 20 through the prefilter 10 and the HEPA
After passing through the filter 30 and gas adjustment system (air adjustment system 40),
After being divided into an iodine generation system 50, a humidification system 60, and a bypass system 70, they were merged in the mixing system 75, flowed into the sample system 80, and passed through the backup system 90 to the exhaust system of the test facility installation building (not shown). Released). When supplying the mixed gas to the sample system 80, the mixed gas flows under the specified test conditions. Hereinafter, it will be described more specifically.

The dust in the atmosphere is almost removed by the pre-filter 10, the dust load of the HEPA filter 30 installed downstream can be reduced, and the usable period of the HEPA filter 30 can be extended. Since the HEPA filter 30 is more expensive than the prefilter 10 generally called a flat filter or rough filter, the cost of replacement can be reduced by reducing the replacement frequency. The blower 20 supplies air used in the test, and the blower 20 may be replaced with a compressor having a pressure regulator.

The air sent by the blower 20 is dehumidified and flow rate adjusted by the air adjusting system 40, then divided into three, and divided into an iodine generating system 50, a humidifying system 60 and a bypass system 60. Since the flow rate is measured and the flow rate is adjusted after dehumidifying, the flow rate can be adjusted extremely accurately without being affected by the fluctuation of the moisture (water vapor) concentration (humidity). In the iodine generation system 50, iodine is generated in a specified chemical form and concentration, and the iodine is placed on the branched air stream. The humidification system 60 is a system through which most of the air flows. Iodine generation system 50,
The humidification system 60 and the bypass system 70 have temperature and flow rate adjusting functions. By dividing the system into three systems in this way, it becomes possible to secure the optimum flow rate for the generation of iodine and the adjustment of humidity, and it becomes easy to set the test conditions, so that the load on the operator can be reduced. Bypass system 70
The flow rate adjusting function of can be replaced by the flow rate adjusting function of the air adjusting system 40.

In the mixing system 75, the gases of the three systems merge again and flow into the sample system 80 under specified test conditions. Since the amount of gas in the iodine generation system 50 is constant, the humidity of the sample system can be adjusted to a set value by adjusting the flow rate ratio between the humidification system 60 and the bypass system 70. By providing the mixing system 75, the iodine concentration, temperature, and humidity become uniform, the reliability of test results is improved, the number of repeated tests can be reduced, the test period, operator working hours can be reduced, and eventually the cost can be reduced. It leads to reduction. In particular, in the case of adsorbents that remove iodine using isotope exchange reaction, radioactive iodine is used as iodine, so the sample system
The gas flowing out of 80 is discharged to the exhaust system of the test facility installation building after removing the leaking radioactive iodine in the backup system 90.

In this case, a test was carried out from the amount A of radioactive iodine collected by the adsorbent tested in the sample system 80 and the amount B of radioactive iodine adsorbed by the iodine adsorbent installed in the backup system 90. The iodine collection efficiency η of the adsorbent is calculated by the following equation. η = A / (A + B) × 100% The backup system 90 is thus not only necessary for calculating the performance of the test adsorbent (iodine collection efficiency η),
The amount of radioactivity released from the equipment is made extremely small, which contributes to the reduction of radiation exposure to the public. Even when non-radioactive iodine is used, the iodine collection efficiency η can be similarly obtained. Also, sampling the gas before and after the adsorbent,
There is also a method of obtaining the iodine collection efficiency η from the iodine concentration in the gas, but it is inferior to the above method in terms of accuracy and detection limit.

Embodiment (Part 2) FIG. 2 is a sectional view showing the structure of a steam generator 63 which is the main equipment of the humidification system 60. 2a is a plan view and b is an elevation view. The air 61 divided into the humidification system 60 flows while returning along the narrow flow path upper part partitioned by the internal partition plate 64 of the steam generator 63. On the other hand, the water 68 whose temperature and flow rate have been adjusted flows in a counterflow with the air. The heaters 62 and 66 for heating the inflow air 61 and the outlet air 611 and the temperature controllers 65 and 67 for controlling the temperature thereof are provided.

In order for the flow of both air and water to be laminar,
The shape and dimensions of the flow channel are set. A laminar flow does not generate water mist here. If water mist is generated and reaches the test sample system 80, it adheres to the surface of the adsorbent, significantly impairs the iodine collection performance, and the true collection performance cannot be evaluated. Therefore, it is necessary to strictly prevent the water mist from coming in. The steam generator 63 takes away the latent heat of vaporization that accompanies the evaporation of water.
The temperature of 61 needs to be higher than the set temperature, and the air heater 62 for that purpose is installed. The outlet temperature of the steam generator 63 is adjusted via the temperature controller 65 by this heater output.

As described above, since it is strictly prohibited to bring water mist into the sample system 80, if the water vapor pressure at the outlet of the steam generator 63 is very close to the saturated water vapor pressure, the flow up to the sample system 80 will occur. If there is a slight decrease in temperature or a part of the wall where the temperature is very low in the road, there is a risk of generating water mist, so the heater 66 is installed to avoid this. By these, the carry-in of the water mist to the test sample system 80 is eliminated, the malfunction performance evaluation due to the adhesion of the water mist is eliminated, and the reliability is improved, and the test period is re-tested,
Cost can be reduced.

Embodiment (No. 3) FIG. 3 shows a steam generator 63, which is the main equipment of the humidification system 60.
FIG. 6 is a cross-sectional view showing another structure of FIG. The air 61 split into the humidification system 60 is first of all, the first steam generating bubble column 63.
After passing through the water 68 introduced from the lower part of 1 by adjusting the temperature and flow rate and removing the water mist with the demister 641,
After being guided to the lower part of the second vapor generating bubble column 632 and removing the water mist by the demister 642, the same procedure as in Example 2 is performed. Heaters 62, 66 for heating the incoming air 61 and the outlet air 611 and a temperature controller 6 for controlling their temperature
The provision of 5, 67 is the same as in the second embodiment. From the temperature detection end of the temperature controller 65 to the sample system 80, the thermostatic chamber 65
It is installed inside 1.

In the first vapor generating bubble column 631, the latent heat of vaporization associated with the evaporation of water is taken away, so the temperature of the inflowing air 61 must be higher than the set temperature, and the air heater 62 for that purpose is required. Has been installed. With this heater output, the outlet temperature of the steam generating bubble column 631 is adjusted to the temperature controller 65.
Adjust via. It is not necessary to strictly remove the water mist at the outlet of the bubble column 631 for generating steam in the first tower, but a demister 641 is installed so that drain does not occur in the pipe up to the bubble column 632 for generating steam in the second tower. There is. In the first vapor bubble generating column 631 for generating steam, since the amount of evaporation of water is large, it is necessary to constantly supply water to compensate for this evaporated water, and the temperature is kept constant to keep the amount of outlet water constant. In order to do so, water 68 having a constant flow rate and temperature is supplied. This supply amount is larger than the amount of evaporated water, and the excess water that has not been evaporated and consumed is
For example, the water is discharged by a method of maintaining the water level of the first water vapor generation bubble column 631 such as overflow. Therefore, the evaporation amount of water in the first-column steam generation bubble column 631 is constant, that is, the moisture content at the outlet of the first-column steam generation bubble column 631 is constant. The humidified air that has left the first-column steam generation bubble column 631 then flows into the second-column steam generation bubble column 632 having the same structure as the first column.

It has been empirically known that the relative humidity at the outlet of the first steam generating bubble column 631 is about 97%. It has also been empirically known that the relative humidity at the outlet of the second steam generating bubble column 632 is 99% or more. Therefore, the amount of water vaporized in the second water vapor generation bubble column 632 is extremely small, and the temperature of the air here hardly changes. The second water vapor generation bubble column 632 after the temperature measurement point of the temperature controller 65 is installed in the constant temperature bath 651, and the influence of disturbance is eliminated to further suppress the temperature change. The make-up water 685 for replenishing the water that slightly evaporates in the second water vapor generation bubble column 632 is of course brought to the same temperature as the constant temperature bath 651 and then introduced into the constant temperature bath 651,
It is replenished to the second steam generating bubble column 632. In the second water vapor generating bubble column 632, since there is almost no temperature change as described above, the make-up water 685 does not need to flow more than the amount of evaporated water to maintain the temperature, and no overflow is required, but a water level holding function. (Water level gauge and make-up water 685 linked to this
Inflow control function) is necessary.

In the second column for generating steam 632, a demister 642 is provided to remove about 98% of mist, but it is not completely removed. Therefore, a mist separator 633 is further installed. . The mist separator 633 is filled with a sub-μm-diameter silica wool layer 643, or a HEPA filter is installed, where 99.9% or more of mist is further removed, and air with saturated humidity with almost no mist is generated. Become. Further, in order to avoid the generation of mist due to a slight temperature decrease, the temperature is raised by the heater 66 and controlled by the temperature controller 67 to the temperature of the test condition. By installing the mixing system 75 and the sample system 80 in the constant temperature bath 651, it is possible to accurately set the test temperature conditions. Although not shown in FIG. 3, the fluids of the temperature-controlled iodine generation system 50 and the bypass system 70 join together in the mixing system 75.

Embodiment (No. 4) FIG. 4 is a sectional structural view of the mixer of the mixing system 75. In the mixer main body 751, the humidified air 611 from the humidification system 60 and the air 5 containing iodine from the iodine generation system 50 are arranged as shown in the figure.
1. Dry air 71 from the bypass system 60 flows in and mixed air 81 flows out.

Humidified air from humidifying system 60 with the highest flow rate
The piping port of 611 is open so as to be discharged toward one end of the mixer main body 751, and the dry air 71 from the bypass system 60 is also the same. The piping opening of the mixed air 81 flowing out faces exactly the opposite side, and the piping opening of the air 51 containing iodine from the iodine generation system 50 is located in the middle of them, and its opening direction is humidified air. In the same direction as 611 and the dry air 71 from the bypass system 60. By adopting this structure, the composition of the mixed air 81 flowing out is mixed and made uniform, and even if the mist should flow in, the streamlines are directed in the opposite direction, so preventing the mist from flowing out. This leads to reliable data acquisition, which in turn reduces the number of tests and costs.

Embodiment (5) FIG. 5 is an iodine generation system for the purpose of generating a single iodine.
It is a systematic diagram of 50. Inside the iodine generating container 52, iodine crystals and glass wool are alternately stacked, and air flows between the iodine crystals. Iodine generation container 52
And the piping upstream thereof are housed inside the constant temperature bath 54. In addition, a line that bypasses these is provided.

Iodine crystals and glass wool are alternately stacked inside the iodine generating container 52, and air is passed between the iodine crystals to sublimate the iodine to form a gas and entrain it in the air. The air 51 is discharged as containing air. By alternately stacking the iodine crystals and the glass wool, the drift of the air is eliminated, the iodine crystals and the air are sufficiently contacted, and the vapor pressure of iodine in the contacted air reaches the saturated vapor pressure.
The vapor pressure of iodine is a function of temperature, and the iodine partial pressure in the air 51 containing iodine, that is, the iodine concentration, can be obtained by installing the iodine generation container 52 and the pipe upstream thereof inside the constant temperature bath 54. Can be set.

When it is not necessary to flow iodine, that is, the period from the start-up of the apparatus to the temperature and humidity of the apparatus as a whole, the flow rate conditions are set to set values, the temperature and humidity holding period for which the specimen is set, and after the test is completed. During the period, the air is caused to flow through the bypass line having the valve 57 by operating the valves 55 to 57. It is needless to say that, at this time, the iodine concentration (vapor pressure) in the iodine generation container 52 is constant and determined by the vapor pressure with respect to the temperature of the constant temperature bath 54 and does not exceed the vapor pressure.

Embodiment (6) FIG. 6 is a system diagram of an iodine generation system 50 for the purpose of generating methyl iodide. Iodine (methyl iodide) generation container
521 Methyl iodide is put inside. The upper part 522 of the iodine generation container 521 is narrow and the upper part is open. The iodine generation container 521 is installed inside the iodine generator 523. The iodine generator 523 is equipped with an air inlet / outlet pipe, and is housed inside the constant temperature bath 54 together with its upstream pipe. In addition, a line that bypasses these is provided.

Methyl iodide is placed inside the iodine (methyl iodide) generation vessel 521. Methyl iodide has a vapor pressure according to temperature, and the vapor pressure is too high near the performance test temperature of the adsorbent. Therefore, if the upper part 522 of the iodine generation container 521 is made thin, the amount of iodine transferred from the iodine generation container 521 to the inside of the iodine generator 523 is the upper part.
It is governed by the diffusion rate, diffusion distance, and diffusion area at 522.
Since the diffusion rate is determined by the temperature and the iodine concentration at the upper end of the upper part 522, the iodine generator 52 should be kept at a constant temperature.
If 3 is installed in the constant temperature bath 54 and kept at a constant temperature, it depends only on the amount of air flowing into the iodine generator 523.

On the contrary, since the amount of air flowing into the iodine generator 523 is determined by the setting conditions of the sample system 80, the shape (length and thickness) and temperature of the upper portion 522 of the iodine generation container 521 are to be determined. By adjusting the iodine concentration from the iodine generation container 521 to the inside of the iodine generator 523, that is, the air inflow amount is constant, the iodine concentration can be adjusted to a predetermined value. Similar to the embodiment (No. 5), when it is not necessary to flow iodine, that is, the period from the start-up of the device to the temperature and humidity of the entire device, the flow rate conditions are set to the set values, and the temperature and humidity of the test piece During the holding period and after the end of the test, the valves 55 to 57 are operated to flow air through the bypass line having the valve 57. It is needless to say that, at this time, the iodine concentration (vapor pressure) in the iodine generation container 52 is constant and determined by the vapor pressure with respect to the temperature of the constant temperature bath 54 and does not exceed the vapor pressure.

Embodiment (No. 7) FIG. 7 is an operation flow chart of the iodine filter performance evaluation apparatus, and FIG. 8 is a system diagram of the sample system 80 and the backup system 90. In FIG. 8, the air 75 set as the test condition is used.
1 passes through the test adsorbent 81 and the backup adsorbent 91, is discharged to the outside of the system, and is discharged to the exhaust system of the test facility building. The air that flows during the setting of the test conditions and after the end of the adsorption test flows through the bypass lines of the respective systems, that is, the 84 valve lines and the 95 installation lines.

The operation procedure of FIG. 7 will be described. (1) Set the temperature of the system through which air passes and wait for it to settle. (2) All systems with a bypass line allow air to flow through this line. (3) Gradually raise the water temperature of the steam generation system to the set value. (4) Check that the temperature, humidity, and flow rate of each line are set. (5) Switch the humidification system (steam generation system) to the main line. (6) Switch the iodine generation system to the main line. (7) Switch the test system and backup system to the main line. (8) After the specified test time, switch the test system and backup system to the bypass line. (9) Switch the iodine generation system to the bypass line. (10) Switch the humidification system (steam generation system) to the bypass line. (11) End of test

First, according to (1), by setting the temperature of each part of the apparatus to a predetermined condition, it is possible to prevent overshoot when the fluid is circulated and to shorten the settling time. According to (10) of the previous test, the system is in a dry state, and in (2), the state is maintained and the fluid (dry air) is allowed to stabilize in temperature in the state of flowing. If the temperature of the steam generation system is suddenly increased, it is inevitable that mist will be generated when returning to the set value in the case of overshoot, so the temperature of the steam generation system is gradually raised to the set value. . Initially, it is inconvenient to use the bypass line in all systems even if the above-mentioned phenomenon should occur (mist jumps to the test adsorbent 81, and this causes the iodine adsorption performance to be underestimated. Therefore, it is preferable that each system is provided with a bypass line.

After that, the main line is switched to, and after the performance test is completed, the bypass line is switched to again.
This operation eliminates the possibility that water will remain as a liquid in the system, and thus the possibility of mist generation, so that the reliability of the test results can be maintained. It should be noted that these operations can be automatically performed by using an electronic computer, a sequencer or the like. Further, by making the pressure loss of the bypass line the same as that of the main line, it is possible to avoid the occurrence of flow rate fluctuation when switching between the bypass line and the main line.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes are made without departing from the gist of the present invention. I will get it.

[0035]

According to the iodine filter performance evaluation apparatus of the present invention, it is possible to perform evaluation under test conditions such as predetermined temperature, humidity and flow velocity, and to operate with a stable iodine amount. In addition, the temperature can be adjusted regardless of the flow velocity, the temperature unevenness is small, and the humidity can be adjusted, and the performance of the elementary filter can be evaluated.

[Brief description of drawings]

FIG. 1 is a flow sheet of an embodiment (part 1),
1 shows a gas distribution system which is the basis of the present invention.

FIG. 2 is a cross-sectional view showing an example of the structure of a steam generator used in the humidification system of the present invention, (a) is a plan view and (b) is an elevation view.

FIG. 3 is a cross-sectional view showing another example of a steam generator used in the humidification system of the present invention.

FIG. 4 is a diagram showing an example of a sectional structure of a mixer used in a mixing system according to the present invention.

FIG. 5 is a system diagram including an iodine generation container used in the iodine generation system of the present invention.

FIG. 6 is a system diagram showing an example of an iodine generation system for the purpose of generating methyl iodide.

FIG. 7 is an operation flowchart of the iodine filter performance evaluation device of the present invention.

FIG. 8 is a system diagram of a sample system and a backup system in the present invention.

FIG. 9 is a configuration diagram showing an example of a conventional iodine removal performance testing device.

[Explanation of symbols]

10 Prefilter 20 blowers 30 HAPA filter 40 Air adjustment system (gas adjustment system) 50 iodine generation system 60 humidification system 70 Bypass system 75 mixed system 80 Specimen system 90 backup system

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G01N 30/48 G01N 30/48 J (72) Inventor Norihisa Mori 1-chome, Wadazaki-cho, Hyogo-ku, Kobe-shi, Hyogo No. 1 No. 1 Mitsubishi Heavy Industries, Ltd. Kobe Shipyard (72) Inventor Masao Kaku No. 12 622, Funeishikawa, Tokai-mura, Naka-gun, Ibaraki Prefecture (72) Innovator, Nakami Hayami Niihama, Arai-cho, Takasago, Hyogo Prefecture 2-chome Ichiban Tsurui Chemical Co., Ltd. Takasago Technical Center

Claims (12)

[Claims] 1. A pre-filter and a particulate filter
Installed in one gas flow path, a gas adjustment system is provided in the downstream of the particulate filter, and the gas flow path in the downstream of the gas adjustment system is an iodine generation system, a humidification system, and a bypass system. Is branched to
In the downstream of each of these systems, the three systems merge again in the mixed system and are connected to the downstream sample system as one gas flow path, and a backup system is installed in the downstream of the sample system. An iodine filter performance evaluation device characterized in that 2. A steam generator is installed in the humidification system, and air and water are brought into contact with each other in a laminar flow in the steam generator to prepare high-humidity air in which water mist is not generated,
The iodine filter performance evaluation device according to claim 1, wherein air is heated upstream of the steam generator and high humidity air is heated downstream of the steam generator. 3. In the humidification system, two vapor generating bubble columns having a built-in demister are installed in series, and a mist separator or fine particles filled with a sub-μm diameter fiber layer is provided downstream of the vapor generating bubble columns. The iodine filter performance evaluation device according to claim 1, wherein a filter is provided and a heater is provided downstream of the mist separator. 4. The constant temperature tank is provided from the inlet temperature measuring point of the second steam generating bubble column, which is the downstream of the steam generating bubble column, to the sample system. The iodine filter performance evaluation device according to claim 3. 5. In a mixer main body provided in the mixing system, inlets of humidified air from the humidification system and dry air from the bypass system and outlets of mixed air at different ends, respectively, It is arranged so as to face the opposite direction toward the outside of the main body, and an inflow position of a gas containing iodine from the iodine generation system is provided between the inflow port and the outflow port. The iodine filter performance evaluation device according to claim 1. 6. In the iodine generation system, an iodine generation container is installed in a constant temperature bath, and iodine crystals and glass wool are alternately stacked inside the iodine generation container. The element filter performance evaluation device according to claim 1, wherein a line that bypasses the element generation container is provided. 7. In the iodine generation system, an iodine generator is installed in a constant temperature bath together with a part of an inflow / outflow pipe for air connected to the iodine generator, and iodine is provided inside the iodine generator. 2. The iodine filter performance evaluation device according to claim 1, wherein a iodine generating container is provided, and the iodine generating container has a thin upper part and an open upper part. 8. The iodine filter performance evaluation apparatus according to claim 1, wherein a bypass line is provided in each of the specimen system and the backup system. 9. A gas that has passed through a fine particle filter after passing through a pre-filter is dehumidified and the flow rate is adjusted, and then divided into three systems of an iodine generation system, a humidification system and a bypass system to flow down to a mixed system. A method for operating an iodine filter performance evaluation device, comprising: merging the gases of the three systems again, and then flowing the gas into the sample system, and supplying the outflowing gas to a backup system of the downstream. 10. The gas is circulated to the iodine generation system and the humidification system after the total amount of gas is circulated in the bypass system, the bypass line of the sample system and the bypass line of the backup system. , A gas is circulated to the sample system and the backup system, and after a predetermined time elapses, gas is returned to the bypass lines of the sample system and the backup system and the bypass system to distribute the total amount of gas. The method for operating an iodine filter performance evaluation apparatus according to claim 8, wherein. 11. The operation of the iodine filter performance evaluation apparatus according to claim 9, wherein the pressure loss of the bypass line is substantially the same as the pressure loss of the main line of the sample system or the backup system. Method. 12. When evaluating the iodine filter performance using the iodine filter performance evaluation apparatus according to any one of claims 1 to 7, the iodine collection efficiency is compared with that of the sample system and the backup. A method for evaluating iodine filter performance, which is characterized in that it is calculated from the amount of iodine collected in the system.