JPH0131301Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is an exhaust gas purification device used when dry collecting dust such as soot and dust from high-temperature exhaust gas discharged from waste incinerators, etc. It is related to.

(Prior art) Conventionally, high-temperature exhaust gas emitted from waste incinerators and various combustion devices has been purified by, for example,
As shown in Japanese Utility Model Publication No. 43997 and Japanese Utility Model Publication No. 55-42104, exhaust gas purification devices are used in which a porous ceramic filter is attached inside the main body of the exhaust gas purification device. This equipment is capable of directly processing high-temperature exhaust gas of over 500℃.
If the differential pressure of the filter increases, backwashing can be used to remove the collected substances on the filter surface and allow continued use, but since the collected substances are not completely removed, the The differential pressure of the filter after backwashing gradually increases, and the operating margin decreases, so the filter must be replaced, and the replaced used filter becomes secondary waste, so the amount of waste generated is reduced. was desired.

In addition, a bag filter is generally known as an exhaust gas purification device, and although it has excellent backwashing properties, it has problems such as stable dust collection performance and soundness under high temperatures have not been demonstrated.

(Problems to be solved by the invention) The present invention solves the conventional problems as described above, can directly process high-temperature exhaust gas, has less clogging, and when clogging occurs. This was completed with the aim of creating an exhaust gas purification device that can be easily backwashed and can be used continuously for a long period of time.

(Means for Solving Problems) The present invention provides an exhaust gas purification device in which a large number of filtration elements are attached to a support plate that divides the inside of the exhaust gas purification device body into an exhaust gas introduction chamber and a purified gas chamber. It is characterized in that a bottomed cylindrical fiber filter made of inorganic fiber is attached to the outer surface of a bottomed cylindrical ceramic filter having a large number of fine holes with a predetermined gap. be.

(Embodiment) Next, the present invention will be described in detail with reference to the illustrated embodiment. 1 is an exhaust gas purification device main body equipped with a gas inlet 2 and a gas outlet 3; 4 is the inside of the exhaust gas purification device main body 1; This is a support plate that divides into a lower exhaust gas introduction chamber 5 and an upper purification gas chamber 6, and a large number of filter elements 8 are suspended by their necks supported by a large number of through holes 7 formed through the support plate 4. It is installed in

The filtration element 8 of the present invention has, for example, an average pore diameter of 40 μm, a maximum pore diameter of 60 μm, a porosity of 35%, and a thickness of 10 μm.
It consists of a bottomed cylindrical ceramic filter 9 made of silicon carbide with a diameter of 2.0 mm in diameter, and a bottomed cylindrical fiber filter 10 made of inorganic fiber attached to its outer surface. The fiber filter 10 is, for example, Sio ₂ .
It is preferable that the fiber be made of high silicate glass fiber containing 96% or more, so that it can be used for a long period of time even at high temperatures of 1000℃ or higher, and the average fiber diameter should be 10 μm or less to ensure high collection efficiency. It is preferable to The ceramic filter 9 has a flange 11 at its upper end that expands toward the opening end surface, and the lower surface of the flange 11 is tapered and forms a contact surface 12 with the support plate 4. The fiber filter 10 has its upper end extended to the above-mentioned contact surface 12 and is supported by the weight of the ceramic filter 9, and the fiber filter 10 serves as a packing to seal between the ceramic filter 9 and the support plate 4. It will also accomplish the following. At this time, it is preferable to provide a gap of 5 mm or more in width between the outer surface of the ceramic filter 9 and the inner surface of the fiber filter 10. By setting this gap to 5 mm or more, it becomes easy to attach the fiber filter 10 to the outer surface of the ceramic filter 9, and the fiber filter 1
A space sufficient to collect and hold fine dust that has passed through the ceramic filter 9 on the surface of the ceramic filter 9 can be secured, and the fiber filter 10 can be easily vibrated during backwashing. Reference numeral 13 denotes a backwashing device using high-pressure air provided in the purified gas chamber 6, which blows off dust attached to the filtration element 8 by blowing compressed air from the compressed air source 14 into the purified gas chamber 6. be able to.

(Function) The device configured as described above guides high-temperature exhaust gas discharged from, for example, a radioactive waste incinerator in a nuclear power plant to the exhaust gas introduction chamber 5, and sucks air from the gas outlet 3, thereby removing the exhaust gas. is support plate 4
Only the purified gas enters the purified gas chamber 6 after being filtered while passing through the filter element 8 attached to the
The gas is taken out from the gas outlet 3 in the same manner as in conventional exhaust gas purification devices. However, in the present invention, the filtration element 8 is composed of a bottomed cylindrical ceramic filter 9 having a large number of fine holes, and a fiber filter 10 made of inorganic fibers attached to its outer surface with a predetermined gap. Since it has a two-layer structure, most of the dust in the exhaust gas is collected by the fiber filter 10.
Some of the fine dust that has passed through is further collected by the ceramic filter 9. In this way, the ceramic filter 9 is replaced by the fiber filter 10.
Since it is only necessary to filter the exhaust gas from which most of the dust has been removed in advance, clogging is less likely to occur and high collection efficiency can be maintained for a long period of time. In addition, when the pressure loss of the filter element 8 gradually increases due to long-term use, the introduction of exhaust gas is stopped and compressed air is injected from the backwash device 13 to backwash the ceramic filter 9.
The dust adhering to the outer surface of the fiber filter 10 falls into the gap with the fiber filter 10, and the fiber filter 10 on the outer surface vibrates freely due to the backwashing pressure, completely removing the dust adhering to the surface. It can be dropped. As mentioned above, since most of the dust adheres to the surface of the fiber filter 10, the filtration ability of the filtration element 8 is significantly restored by this backwashing. Such a fiber filter 1
Since the backwashing effect for the ceramic filter 9 is greater than that for the ceramic filter 9, the backwashing frequency can be reduced compared to the case of the ceramic filter 9 alone. Even if it becomes difficult, it is only necessary to replace the fiber filter 10 made of inorganic fibers, so running costs can be reduced and the amount of secondary waste generated can also be reduced. It goes without saying that the filtration element 8 used in the present invention has the advantage of not only being able to directly process high-temperature exhaust gas but also being able to cause re-combustion on the surface of the filtration element 8.

(Effects of the invention) As is clear from the above explanation, this invention is highly reliable and can directly purify high-temperature exhaust gas without cooling it, and can efficiently collect even the finest dust. It is hard to get clogged, and it is easy to backwash, and even if it becomes difficult to continue using it, you only need to replace the maintenance filter, which reduces secondary waste. It also has advantages. Therefore, the present invention has extremely great practical value as it is suitable for purifying high-temperature exhaust gas discharged from waste incinerators and the like.

[Brief explanation of the drawing]

The drawing is a partially cutaway front view showing an embodiment of the present invention. 1... Exhaust gas purification device main body, 4... Support plate, 5
...Exhaust gas introduction chamber, 6...Purification gas chamber, 8...Filtering element, 9...Ceramic filter, 10
...Fiber filter, 12...Contact surface, 13...Backwashing device.

Claims (1)

[Claims for Utility Model Registration] 1. In an exhaust gas purification device in which a large number of filtration elements 8 are attached to a support plate 4 that divides the inside of an exhaust gas purification device main body 1 into an exhaust gas introduction chamber 5 and a purified gas chamber 6, the filtration elements Reference numeral 8 is characterized in that a bottomed cylindrical fiber filter 10 made of inorganic fiber is attached to the outer surface of a bottomed cylindrical ceramic filter 9 having a large number of fine through holes with a predetermined gap. Exhaust gas purification equipment. 2.Ceramic filter 9 is made of silicon carbide, and fiber filter 10 is made of high silicate glass fiber containing 96% or more of Sio ₂ and having an average fiber diameter of 10 μm or less.Claim 1 of Claims for Registration of a Utility Model Exhaust gas purification device described. 3 Utility model registration claim 1, in which the fiber filter 10 is supported at its upper end by the contact surface 12 between the support plate 4 and the ceramic filter 9
The exhaust gas purification device according to item 1 or 2. 4 Backwashing device 13 using high pressure air in the purified gas chamber 6
An exhaust gas purification device according to claim 1, 2, or 3 of the utility model registration claim.