JPS5962329A - Catalyst regeneration method - Google Patents

Abstract

PURPOSE:To regenerate economically a denitration catalyst in a very short time, by washing the deteriorated aged catalyst incorporated in a horizontal flow-type denitration reacter by a washing equipment consisting of a standing part and a temporary part, and drying by the heat source of a boiler or the like. CONSTITUTION:A stop valve 5 is opened gradually adjusting the water pressure to 2-3kg/cm<2> using a pressure gauge 6, and atomized water is sprayed over a catalyst in a catalyst pack 2. The sprayed water is collected in a duct 14, and discharged 18 via a flexible hose 4 and a draining hopper 12. After washing, the compressed air at about 4-5kg/cm<2> is introduced 3 and the water remaining in the pack 2 is removed. An inlet duct 13 and a duct 14 are detached and a nozzle header 8, the nozzle 9 and a water supply pipe are transferred to the unwashed part of the pack 2. Then, the header 8 is positioned, the nozzle 9 is set vertically, and a wash inlet and the ducts 13, 14 are bolted to carry out washing and water removal as described above. After washing, the temporary part of the washing equipment is removed, and the catalyst is dried by the heated air from a heat source of a boiler or the like and regenerated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method VC that can regenerate a denitrification catalyst installed in a cross-flow type denitrification reactor while it is still installed in the device.

The denitrification performance of the denitrification catalyst built into the denitrification reactor is
Deteriorates over time. This occurs due to the adhesion of various poisonous components, such as alkali metals, to the catalyst in the treatment of boiler exhaust gas using C heavy oil due to long-term use, or adsorption of dust containing organic matter in the exhaust gas.

Catalysts whose denitrification performance has deteriorated lose their practical effectiveness, so it is necessary to dispose of them or take measures for economical regeneration.

Conventionally proposed methods for regenerating this catalyst include 7.
Method of firing at 00 to 800℃ (t￥f
No. 3787], a method of firing at 100 to 500°C after washing with water (Japanese Unexamined Patent Publication No. 153789/1989), etc., and these methods are recognized to be effective, but in order to carry out these methods, a denitrification reaction is required. The denitrification catalyst must be removed from the equipment, which not only requires a very long process time but is also economically disadvantageous.

The present invention has been made to eliminate such drawbacks, and provides a method for regenerating a catalyst whose denitrification performance has deteriorated while it is still installed in a denitrification reactor.

That is, in the present invention, a denitrification catalyst installed in a cross-flow type denitrification reactor that has deteriorated over time is washed with water using a water washing device consisting of a permanent part and a temporary part, while it is still installed in the equipment, and then The present invention relates to a method VC for regenerating a denitrification catalyst, which is characterized by drying using a boiler heat source or exhaust gas during boiler firing.

Hereinafter, the method of the present invention will be explained in detail with reference to the accompanying drawings.

FIGS. 1(A) and 1(B) are diagrams showing an example of a cross-flow type denitrification reactor according to the method of the present invention; FIG. 1(A) is a cross-sectional view;
Figure 1 (B) is a view from arrow A in Figure 1 (A), Figure 2 (A)
, CB) are detailed views of the catalyst back portion indicated by the reference numeral 2 in FIGS. 1(A), C, and B), and FIG.
, B) is a view taken along the line AA in FIG. 2(A).

In Fig. 1 (A), (B) and Fig. 2 (A), (B), 1 is the cross-flow type denitrification reaction [equipment body], and 2 is the catalyst bag made of shaped steel built into the device 1. , tens to hundreds of denitrification catalysts 15 are filled. 3 to 14 are parts related to the water washing device according to the method of the present invention, in which the main water supply pipe 3, the gate valve 5, the pressure gauge 6, the intake port 10, the drainage valve 11 and the drainage hopper 12 are permanent parts, and the flexible hose 4.4 'Water supply pipe 7, ladder to nozzle 8, nozzle 9, water washing inlet duct 1
6 and a water washing outlet duct 14 are installed in the temporary part. In addition,
The water washing inlet and outlet ducts 15 and 14 are made of a frame made of light metal such as aluminum and covered with a hood made of vinyl or the like, and are easy to assemble within the reactor 1.
14 is attached to the flange portion 16 of the catalyst bag 2 with bolts 17, as shown in FIGS. 2(A) and 2(CB)K.

In the above-mentioned water washing apparatus, a temporary part is first assembled within the reaction apparatus prior to the water washing operation. That is, catalyst bag 2
The nozzle header 8 is positioned approximately 600 to 500 mm upstream of the flow direction of the gas to be treated (G) so that the nozzle 9 is perpendicular to the catalyst.
゜14 as above with bolt 17 to flange part 16VC
Install. Next, the water tank ysvc flexible hose 4 is fully connected, and this is inserted into the reactor 1 through the inlet 10 and connected to the water supply pipe 7, and the outlet duct 14 is connected to the drainage hopper through the flexible hose 4'. Connect with 12.

After completing the above assembly, perform a water washing operation.

Washing with water is a breeze! The JJ valve 5 is gradually opened, the water pressure is adjusted to 2 to 3 (9/α2) using the pressure gauge 6, and the nozzle 9 injects lip-shaped water onto the catalyst. The sprayed water comes out Rodak 1-1
4, and is extracted from a line 18 through a flexible hose 4' and a drainage hopper 12. The washing time is
This should be done until the concentration of pollutants such as alkali metals in the wastewater reaches almost zero.

When this water washing operation is completed, the pressure 4~ from the water supply main 3
Compressed air of about 5 kg/1yn2 is introduced to remove moisture remaining in the catalyst bag 2.

After that, the inlet duct 16 for washing and the outlet duct 14 for washing are removed, and the nozzle header 8, nozzle 9, and water supply pipe 7 are placed in the part of the catalyst bag 2 that has not been washed yet as shown in Fig. 1 (AJ, (B)). Transfer the nozzle header 8 to its original position as described above, set the nozzle 9 vertically, install the water washing inlet and outlet rods with the I7 bolts, and perform the water washing and water removal operations as described above.

During this water washing, the water washing inlet and outlet ducts 16°14 are
nozzle? This prevents the sprayed water from scattering all the poisonous substances and splashing onto the catalyst, which has already been watered, and contaminating the entire catalyst.

After performing the above operations on all of the catalyst bags 2 and washing them all, remove the temporary part of the washing section J.
The heat source of the boiler, for example, the steam type % type %), the hot air from the blower (FDP), the air preheater (AH), or the exhaust gas from the boiler firing is passed through the path of the gas to be treated G in the reactor 1. dry. In addition, since high-quality fuel such as light oil is used when the boiler is fired, the catalyst is not poisoned by the waste.

In accordance with the above operation mode, a denitrification catalyst whose initial performance was 88% was regenerated to 78%, and the performance was recovered at 87%t.

At this time, the properties of the gas to be treated before and after the regeneration were as follows: Gas temperature: 385° C. Gas composition: Population: NoX: 100 ppm; Inlet box: 110 ppm; and the washing conditions and drying conditions were as follows.

Washing conditions Water quality: Industrial water Amount of water: 10 times the apparent volume of the catalyst Water temperature: Room temperature Time = 1 hour Drying conditions Heat source used: Boiler using light oil Exhaust gas at 120°C when shutting down Time: 1 hour after washing the above catalyst The denitrification performance indicates the denitrification rate determined by the formula below.

Inlet NOx concentration (However, all NOx concentrations are 024 attack equivalent values.) As detailed above, according to the method of the present invention, it is possible to regenerate the denitrification catalyst while it is installed in the cross-flow type denitrification reactor. , Regeneration V?--The required time is extremely short, and it is economically advantageous.

[Brief explanation of drawings]

FIGS. 1(A) and 1(B) are diagrams showing an example of a cross-flow type denitrification reaction shield according to the method of the present invention, and FIG. 1(A) is a cross-sectional view;
Fig. 1 CB) is a view in the direction of arrow A in Fig. 1 (A), and PjfJ2 Figs. So, Figure 2 (A) is a cross-sectional view,
FIG. 2<, B) is a view taken along the line A--A in FIG. 2(A). Sub-Agents 1) Post-August Agent Ryo Hagiwara - Ten (A) Figure 2 (A) (B) 5 13-1624 Enjoji, Kasamatsu-cho, Hashima-gun, Gifu Prefecture ■Applicant Nippon Insulator Co., Ltd. Mizuho-ku, Nagoya City Sudacho 2-56

Claims (1)

[Claims] In a method for regenerating a denitrification catalyst incorporated in a cross-flow type denitrification reaction device, the catalyst is washed with water in a water washing device consisting of a permanent part and a temporary part while it is still installed in the device, and then the boiler heat source or boiler A catalyst regeneration method characterized by drying with exhaust gas during firing.