JPS5933875B2 - Filter device for solid/gas separation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a filter device for solid/gas separation with a long-life structure, which is capable of microwave heating and thereby regenerates a filter element that has become clogged due to moisture. It is related to.

High-performance filters are used for processing wet first stage off-gas in nuclear fuel processing sclera, wet first stage off-gas treatment for reprocessing sclera, scrubber exhaust treatment, and other areas such as clean rooms and building air supply systems. It is used.

Conventionally, such high-performance filters have been replaced with new filters based only on the phenomenon of increased pressure loss, without sufficiently examining the cause or taking any measures to extend the service life.

In particular, when a high-performance filter is used in the wet type 1, the lifespan is about % of that in the dry type 1, which not only increases costs but also increases the amount of waste generated. This was a big problem that had to be solved.

In other words, it has been strongly desired that even a high-performance filter used in the first wet process can be used for a long period of time comparable to a high-performance filter used in the first dry process.

The purpose of the present invention was to solve such technical problems, and it is an object of the present invention to provide a filter that is recyclable and has a significantly extended service life, with almost no structural complexity compared to conventional filters. An object of the present invention is to provide a filter device for solid/gas separation.

In order to achieve this object, the filter device according to the present invention is designed to prevent clogging caused by solid particles and moisture containing moisture, and when used in wet type 1, filter clogging is caused mainly by solid particles and moisture containing moisture. It was devised by focusing on the fact that clogging is a problem, and when pressure loss increases, microwaves are applied, which removes moisture, which is one of the causes of clogging, and regenerates and extends the lifespan. It is structured so that it can be

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is an explanatory diagram showing an example of the present invention.

A high-performance filter element 2 made of glass fiber, mineral fiber, etc. is housed inside an outer box 1 made of a microwave reflective material (for example, metal such as stainless steel or carbon steel).

At both ends of the outer box 1, there are provided an air supply port 4 and an exhaust port 5 for the gas to be treated, each having a microwave leakage prevention plate 3 such as a wire mesh or a punching plate, and are connected to each other through a connecting joint 6. It is connected to the air supply duct T and the exhaust duct 8.

Further, the outer box 1 is provided with a microwave inlet 10 equipped with a microwave-transparent radioactive material backflow prevention plate 9 made of, for example, glass or tetrafluoroethylene polymer.

This leprosy example uses a commercially available high-performance filter with some improvements and the duct is used as is. Normal microwave heating requires about 1 to 2 kW, but in the case of the present invention, the power is ≥45 kW.
Approximately 0MH15k, W is preferable.

One reason why microwave heating is used is because heat is absorbed by moisture, making it ideal for heating damp or wet items.

The degree of moisture in the gas to be treated is almost 10 in the case of a wet method.
0%, but of course it may be less than 100%.

Another reason for adopting microwave heating is that radioactive materials can be blocked by installing a radioactive material backflow prevention plate 9.
This is because it can be isolated and is excellent from the standpoint of preventing contamination.

The practical example shown in FIG. 2 uses a commercially available high-performance filter as is, with some improvements made on the duct side, and is basically the same as the one shown in FIG. 1.

A high-performance filter element 12 is housed inside an outer box 11 made of a microwave reflective material.

The air supply port 14 and exhaust port 15 for the gas to be processed, which are provided on both sides of the outer box 11, are connected to the air supply duct 17 and the exhaust duct 18, respectively, via the connection joint 16, but both connections A microwave leakage prevention plate 13 is installed on the joint 16, the air supply duct 17, and the exhaust duct 18.

Further, a microwave inlet 20 is provided at a position closer to the filter element than the microwave leakage prevention plate 13 of the exhaust duct 18.
is provided, and a microwave-transparent radioactive substance backflow prevention plate 19 is installed inside the plate.

The one in Figure 1 is arranged so that the microwave is directly irradiated to the high-performance filter element 2, whereas
The one in Figure 2 is different in that this is not the case.

However, the same is true in that the microwaves are scattered and ultimately irradiate the element.

In this way, there is an advantage that only the duct side can be improved without making any changes to the filter side.

FIG. 3 shows still another practical example of the present invention, in which only the filter element is replaceable.

A high-performance filter element 22 is housed inside an outer box 21 made of a microwave reflective material.

The outer box 21 includes an air supply duct 27 and an exhaust duct 28 for the gas to be treated, each having a microwave leakage prevention plate 23.
Furthermore, a microwave inlet 30 having a microwave-transparent radioactive material backflow prevention plate 29 is provided.

Further, the outer box 21 has a filter element carry-out port 31 open and is closed with a lid 32 which also has a microwave leakage prevention function.

In any of the practical examples, the gas to be treated that enters through the supply air duct is separated into solid and gas by the filter element, and then discharged through the exhaust duct.

Moisture contained in the gas to be treated adheres to the filter element, increasing pressure loss.

At this time, when microwaves are introduced from the microwave inlet, the filter element is heated and evaporated to dryness, moisture is removed, and the pressure loss of the filter is reduced.

The microwave-transparent radioactive material backflow prevention plate 29 functions to prevent the gas to be processed from leaking to the outside, for example, to a microwave generator, and the microwave leakage prevention plate 29 prevents the microwave from leaking to the outside, for example, to a microwave generator. It functions to prevent microwaves from leaking outside when applied.

Experiments have confirmed that clogged high-performance filters can be regenerated by microwave heating.

The results are shown in FIG. In fact, the high-performance filter used in the experiment was the one used in wet type 1, and the pressure loss was 100 mmAq.

When this filter was heated and dried by applying microwaves, the pressure loss of the filter was approximately 47 mmAq in approximately 20 minutes.
It dropped to .

In addition, the pressure loss before use of a filter of the same type as this is approximately 4
0 mmAq (indicated by a broken line).

The results showed that, depending on the amount of filter elements and the output of the microwave, it was possible to regenerate a filter that had been clogged with moisture by applying microwaves for several tens of minutes, and that it could be used several times. .

Every time the pressure loss increases, heat treatment is performed by applying microwaves, and when the clogging is finally caused mainly by solid particles, the filter must be replaced.

In the case of the practical examples shown in FIGS. 1 and 2, the connection joint 6,
All you have to do is replace the outer boxes 1 and 11 with new ones starting at point 16. In the case of the actual paper example shown in Fig. 3, only the filter element 22 can be shown with a virtual line using the filter element removal number 31. You can replace it with .

Although the practical examples of the present invention have been described above, it goes without saying that the positions and shapes of the microwave inlet and the microwave leakage prevention mechanism are not limited to those shown in the drawings, but can be changed as appropriate.

In addition, a high-performance filter (I(
Although only the EPA filter has been described, it may be a general filter for hard and sensitive women.

Usually, a small and portable microwave generator is sufficient, and heating only needs to be done when the pressure drop becomes large, so each time it is necessary to connect the clogged filter and heat it again. Bye.

In addition, a microwave generator is connected to each filter, and differential pressure gauges are installed on both sides of the filter element, so that when the differential pressure increases above a certain level, microwaves are applied, and when the differential pressure falls below a certain value, the microwave is applied. It is also possible to turn it off, so-called automation.

Since the present invention is configured as described above, it is structurally almost not complicated compared to conventional filters, and
Not only can the life of the filter be significantly extended and the cost required for filter replacement can be reduced, but also the amount of waste generated can be reduced, and other excellent effects can be achieved.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing one practical example of the present invention, FIGS. 2 and 3 are explanatory diagrams showing other practical examples of the present invention, and FIG. 4 is an explanatory diagram showing the effectiveness of the present invention. This is a graph of the results of the first experiment. Lll, 21...Outer box, 2,12.22...
...filter element, 3,13.23...
・Microwave leakage prevention plate, 7, 17.27...
Air supply duct, 8.18.28...exhaust duct,
10,20.30...Microwave inlet.

Claims (1)

[Claims] 1. Consisting of an outer box made of a microwave reflective material and a filter element housed inside the outer box, the supply and exhaust system for the gas to be treated that communicates with the outer box is equipped with a microwave leakage prevention plate. A filter device for solid/gas separation, characterized in that a microwave inlet having a backflow prevention plate for a gas to be treated is provided in a region where microwaves are confined by an outer box and a microwave leakage prevention plate.