JPH06182229A - Catalyst carrying method for ceramic catalyst filter - Google Patents

Abstract

PURPOSE:To decrease the contamination of a catalyst with poison by applying a catalyst aq. soln. at the outlet side of the exhaust gas of a ceramic filter and blowing a hot air from the outlet side of the exhaust gas to the inlet side of the exhaust gas. CONSTITUTION:The catalyst aq. soln. is applied on the inside wall 1a located at the outlet side of the exhaust gas. A ceramic filter 1 is rotated through a filter fixture 3, and a hot air is supplied from a hot air supply nozzle 4. The hot air 2 is ejected from the hot air supply nozzle 4 to the ceramic filter 1 and allowed to flow from the inside wall 1a of the ceramic filter 1 to the outside wall 1b. The catalyst aq. soln. is dried by the hot air 2, and the catalyst is stuck on the surface of the inside wall 1a, and allowed to flowin to the outside wall 1b side little by little. Therefore, the concentration distribution of the catalyst is high at the inside wall 1a side of the outlet side and low at the outside wall 1b of the inlet side. In this way, the degradation of the catalyst is prevented, and the catalyst to be contaminated by poison is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for supporting a catalyst on a ceramic catalyst filter used for dust removal and denitration of exhaust gas.

[0002]

2. Description of the Related Art A conventional ceramic catalyst filter is formed of a porous ceramic carrying a catalyst, and hot exhaust gas or the like is passed through this ceramic catalyst filter, and at this time, denitration is performed by the catalyst. I am trying. Also, in this conventional ceramic catalyst filter,
The catalyst is supported on the entire porous ceramic.

[0003]

When the catalyst comes into direct contact with the oil mist in the exhaust gas, the catalyst is poisoned and does not function as a catalyst. In the conventional ceramic catalyst filter described above, since the catalyst is supported on the whole ceramic, the oil mist in the exhaust gas touches the catalyst at the inlet side portion of the ceramic catalyst filter to cause poisoning of the catalyst, There is a drawback that the function as is not generated.

The present invention is intended to provide a method for supporting a catalyst of a ceramic filter which can solve the above-mentioned drawbacks.

[0005]

A method for supporting a catalyst of a ceramic catalyst filter of the present invention is a ceramic catalyst filter carrying a catalyst for purifying exhaust gas, wherein a catalyst solution is attached to the exhaust gas outlet side of the ceramic filter, and the exhaust gas is discharged from the exhaust gas outlet side. It is characterized by blowing hot air toward the entrance side.

[0006]

In the present invention, the catalyst solution is applied to the outlet side of the ceramic filter, and hot air is blown from the exhaust gas outlet toward the exhaust gas inlet side, so that the catalyst adheres to the outlet side surface of the ceramic filter and gradually moves to the inlet side. The concentration distribution of the flow-in catalyst is high on the outlet side and low on the inlet side.

As described above, by mainly supporting the catalyst on the outlet side of the ceramic catalyst filter, it is possible to reduce the direct contact between the catalyst and the dirty gas containing the oil mist or soot that reaches the filter inlet side, thereby reducing the catalyst. The function can be kept high. Further, the hot air can prevent the filter from being clogged.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. A plurality of cylindrical porous ceramic catalyst filters 1 carrying a catalyst according to this embodiment are shown in FIG.
As shown in FIG. 4, the exhaust gas from the prime mover and the like is arranged vertically in the ceramic filter device 11, enters the ceramic filter device 11 through the inlet of the ceramic filter device 11 as shown by arrow a, and the exhaust gas from arrow c As shown, the ceramic catalyst filter 1 is dedusted (filtered) and denitrated when passing from the outer wall to the inner wall. The cleaned gas enters the chamber 12 above the ceramic filter device 11 and is discharged from the outlet duct 15 as shown by the arrow b. In addition, the lower part 1 of the ceramic filter device 11
Numeral 3 has a hopper shape for discharging the soot collected.

A catalyst supporting method according to this embodiment of the ceramic catalyst filter used in the above ceramic filter device will be described with reference to FIG. Reference numeral 1 denotes a cylindrical ceramic filter, and an aqueous catalyst solution is applied to the inner wall 1a on the exhaust gas outlet side. 3 is a ceramic filter 1
It is a filter mounting jig that airtightly supports both ends of
A hot air supply nozzle 4 that penetrates one side of the filter mounting jig 3 and extends into the ceramic filter 1 and has a plurality of ejection holes.
Is provided. Further, the filter mounting jig 3 is
A mechanism (not shown) rotates around the central axis of the ceramic filter 1. Note that arrow c
2 is a flow direction of the exhaust gas when the ceramic filter 1 is arranged in the ceramic filter device as shown in FIG. 2, and 1b is an outer wall of the ceramic filter on the exhaust gas inlet side.

In this embodiment, the ceramic filter 1 is rotated through the filter mounting jig 3 to supply hot air from the hot air supply nozzle 4. The hot air 2 is ejected from the hot air supply nozzle 4 into the ceramic filter 1 and flows from the inner wall 1a of the ceramic filter 1 to the outer wall 1b. This hot air 2
The catalyst aqueous solution is dried by, the catalyst adheres to the surface of the inner wall 1a, and gradually flows into the outer wall 1b side. Therefore, the catalyst concentration distribution is high on the outlet side inner wall 1a side and low on the inlet side outer wall 1b side. Further, by rotating the ceramic filter 1 around its central axis through the filter mounting jig 3, the catalyst is evenly attached to the entire surface of the inner wall 1a without deviation.

As described above, in the ceramic catalyst filter carrying the catalyst according to the present embodiment, the catalyst concentration is low on the outer wall 1b side which is the exhaust gas inlet side, and the catalyst concentration is on the inner wall 1a side which is the exhaust gas outlet side. Since the exhaust gas has a high temperature, the oil mist in the exhaust gas, isotopes, etc. do not come into direct contact with the catalyst, and the deterioration of the catalytic function can be prevented. Further, the hot air can prevent the ceramic filter 1 from being clogged.

A second embodiment of the present invention will be described with reference to FIG. The present embodiment relates to a method of supporting a catalyst on the flat ceramic filter 1. On the exhaust gas outlet side surface (upper surface) 1a of the flat plate-shaped porous ceramic filter 1,
The catalyst aqueous solution is evenly applied, and hot air d is evenly flowed from the outlet side surface 1a of the ceramic filter to the ceramic filter exhaust gas inlet side surface (lower surface) 1b.

As a result, the catalyst is evenly adhered to the exhaust gas outlet surface 1a of the ceramic filter 1 and gradually flows into the outlet surface 1b, and the catalyst concentration is low on the inlet surface 1a side and the outlet surface 1a. It becomes higher on the 1b side.

The ceramic catalyst filter carrying the catalyst according to the present embodiment can exhibit the same action and effect as the ceramic catalyst filter according to the first embodiment.

A third embodiment of the present invention will be described with reference to FIG. Contrary to the first embodiment, the ceramic catalyst filter according to the present embodiment is of a type in which exhaust gas flows from the inner wall to the outer wall of the filter.

Both ends of the cylindrical porous ceramic filter 1 are closed by plugs or the like, and as shown in FIG. 4 (a), the ceramic filter 1 is immersed in a water tank 21 containing a catalyst solution, An aqueous catalyst solution is attached on the outer wall. Next, as shown in FIG. 4B, the ceramic filter 1 is placed on the dedicated stand 24, and the ceramic filter 1 is attached with an arrow f.
While rolling with the dedicated stand 24 as shown in
The hot air 25 is sent from the dryer 23 on the side of the ceramic filter 1, and the hot air 25 is applied to the entire outer wall of the ceramic filter 1 to flow toward the inner wall of the ceramic filter 1, thereby drying the catalyst aqueous solution to transfer the catalyst to the ceramic filter 1. Attach it.

In this embodiment, the catalyst concentration is increased on the outer wall side of the ceramic filter, which is the exhaust gas outlet side, and the catalyst is on the inner wall side of the ceramic filter, which is the exhaust gas inlet side, as in each of the above embodiments. The concentration can be reduced, and the ceramic catalyst filter supporting the catalyst according to the present embodiment can exhibit the same operation and effect as the ceramic catalyst filter supporting the catalyst according to each of the embodiments.

[0018]

According to the present invention, by a simple method,
The catalyst concentration distribution can be lowered on the exhaust gas inlet side of the ceramic catalyst filter and can be raised on the exhaust gas outlet side, so that the catalyst can be prevented from deteriorating and the catalyst loss can be prevented because the poisoned catalyst is reduced. Further, since hot air is blown when the catalyst is supported, it is possible to prevent the filter from being clogged.

[Brief description of drawings]

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

FIG. 2 is a vertical sectional view of a ceramic filter device using a ceramic catalyst filter carrying a catalyst according to the first embodiment.

FIG. 3 is an explanatory diagram of a second embodiment of the present invention.

FIG. 4 is an explanatory diagram of a third embodiment of the present invention.

[Explanation of symbols]

 1 Ceramic filter 1a Inner wall, exhaust gas inlet side surface 1b Outer wall, exhaust gas outlet side surface 2 Hot air 3 Filter mounting jig 4 Hot air supply nozzle 21 Water tank 23 Dryer 24 Dedicated stand 25 Hot air

Claims (1)

[Claims] 1. A ceramic catalyst filter carrying an exhaust gas purifying catalyst, characterized in that a catalyst solution is applied to an exhaust gas outlet side of the ceramic filter and hot air is blown from the exhaust gas outlet side toward the exhaust gas inlet side. Method for supporting catalyst.