JPH02223625A - Blocking prevention device of aqueous ammonia atomizing nozzle in denitration device - Google Patents

Abstract

PURPOSE:To remove easily soot in exhaust gas entering or adhering to an aqueous ammonia atomizing nozzle by connecting compressed air piping and aqueous ammonia piping through a cleaning magnetic valve. CONSTITUTION:An aqueous ammonia supply source is connected to the aqueous ammonia supply port 9a of an aqueous ammonia atomizing nozzle 5' through a check valve 12a and an ammonia supply magnetic valve 12. To a compressed air supply port 10a, a compressed air supply source is connected through a compressed air supply magnetic valve 11. Moreover, a cleaning magnetic valve 13 is connected to the aqueous ammonia supply port 9a through a check valve 13a. As a result, the cleaning magnetic valve 13 is opened for a short time while the aqueous ammonia atomizing nozzle 5' is operating, so that compressed air is jetted from the aqueous ammonia supply port 9a to the nozzle portion through the check valve 13a. It is thus possible to blow off the soot in exhaust gas entering the inside of the nozzle in a moment.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for preventing clogging of an ammonia water spray nozzle in an exhaust gas denitrification device.

[Prior Art] First, an outline of the configuration of a denitrification device to which the ammonia water spray nozzle of the present invention is applied will be explained with reference to FIG.

In the figure, l is an engine such as a diesel engine,
2 is the catalytic reactor, 4 is the elbow. An ammonia mixing device consisting of an ammonia water spray nozzle 5, 6 and 7 are supply pipes, and 8 is an exhaust pipe, the exhaust gas discharged from the engine 1 through the supply pipe 6 is mixed with ammonia water atomized in the mixing device. By mixing, the gas becomes a gas mixed with ammonia gas, which is supplied to the catalytic reactor 2 through the supply pipe 7, where a considerable amount of N O is generated under the catalyst in the reactor 2.
X is reduced to nitrogen and water, reducing the amount of NO8 to an appropriate value, and is discharged from the exhaust pipe 8.

By the way, the ammonia mixture mentioned above! The internal structure of the ammonia water spray nozzle 5 incorporated in 3 is as shown in FIG.

That is, as shown in the figure, the ammonia water spray nozzle 5 has a double structure of an internal cylinder 9 that supplies ammonia water and an external cylinder 10 that supplies compressed air.

In addition, an ammonia water path 9b that is connected to an ammonia water supply port 9a formed at the lower end of the internal cylinder 9 and gradually tapers 7 is formed inward, and a nozzle portion 9C is formed at the most extreme end of the ammonia water path 9b. be done.

Further, a compressed air passage 10b communicating with the compressed air supply ports 10a is formed at the side of the outer cylinder 10 in the gap between the inner wall of the outer cylinder and the outer wall of the inner cylinder.

[Problems to be Solved by the Invention] In the conventional ammonia water spray nozzle 5, some of the soot mixed in the exhaust gas is mixed in the ammonia mixing device 1 during the mixing process of the ammonia water and the exhaust gas. Susu S
, flows back into the nozzle portion 9c due to the backflow, and some other soot S2 adheres to the tip of the nozzle portion 9c.

In this case, as shown in the second diagram, ammonia water is supplied from a supply port 9all separate from the compressed air using a head difference,
Because the pressure is low, soot S1. The presence of S2 causes a situation in which the spouting of ammonia water does not cause any trouble.

Therefore, in the conventional type, before soot flows back into the nozzle part 9C of the ammonia water spray nozzle 5 or adheres to the tip of the nozzle part 9c and clogs the ammonia water passage 9b, the ammonia water spray nozzle 5 is periodically removed. was removed from the ammonia mixing equipment and cleaned to remove soot.
Performing such cleaning regularly is troublesome, and
During this period of cleaning, ammonia water cannot be sent to the catalytic reactor 2, so there is a drawback (problem) that the denitrification action is not performed during this period.

An object of the present invention is to provide a base opening prevention device for an ammonia water spray nozzle in a denitrification device that solves the above-mentioned problems.

[Means for Solving the Problems] The present invention connects the ammonia water supply source of the ammonia water spray nozzle to the ammonia water supply source through a check valve and a ttm valve for ammonia water, while the ammonia water A compressed air source is connected to the compressed air supply port of the spray nozzle via a solenoid valve for supplying compressed air, and a solenoid valve for supplying cleaning air is connected to the ammonia supply port of the spray nozzle via a check valve. The present invention relates to a blockage prevention device for an ammonia water spray nozzle in a denitrification device, which is connected to a water supply port and periodically opens a solenoid valve for supplying cleaning air for a short period of time while the ammonia spray nozzle is in operation.

[Example] The present invention will be specifically described below with reference to an example shown in FIG.

In the figure, 5' is an ammonia water spray nozzle incorporated in the ammonia mixing device, which may basically have the same configuration as the ammonia water spray nozzle 5 in FIG.

The reason why the outer shape of the ammonia water spray nozzle 5'' is slightly different from that of the ammonia water spray nozzle 5 is that in the ammonia water spray nozzle 5', the ammonia water spray nozzle 5' shown in the second figure is housed in a nozzle storage tube and the outer shape is adjusted. This is because it displayed something.

Therefore, the ammonia supply port 9a, the compressed air supply port 1
0a indicates corresponding parts with the same reference numerals.

Further, other corresponding parts will also be explained using the reference numerals shown in FIG.

Reference numeral 11 denotes a solenoid valve for supplying compressed air, which is connected via piping between the compressed air source and the compressed air supply port 10a of the ammonia water spray nozzle 5'. 12 is a solenoid valve for ammonia supply, and the ammonia water supply port 9a of the ammonia water spray nozzle 5' is connected to the ammonia water supply source via the check valve 12a.

13 is a solenoid valve for supplying cleaning air, and the ammonia water supply port 9a is connected to a compressed air source via a check valve 13a.

[Operation] When the solenoid valves 11 and 12 are operated and opened and ammonia water is supplied from the supply port 9a and compressed air is supplied from the supply port 10a, the nozzle portion 9 at the tip of the ammonia water spray nozzle 5'
Atomized ammonia water is ejected from C.

By the way, as shown in FIG. 3, the ammonia water spray nozzle 5' is installed in the ammonia mixing device so that its tip is inserted into the elbow 4 where the exhaust gas is supplied, as shown in FIG. As described above, the soot mixed in the exhaust gas enters the inside of the nozzle portion 9C or adheres to the tip portion as shown by s and S2 in FIG. 2 due to backflow or the like.

By the way, in the present invention, the solenoid valve 13 for supplying cleaning air is opened for a short period of time (for example, 30 seconds) while the ammonia water spray nozzle 5' is operating while the engine 1 is operating, that is, during the injection of ammonia water. This causes the compressed air to flow through the solenoid valve 1.
3 through the check valve 13a from the supply port 9a through the ammonia water passage 9b to the nozzle portion 9C, so that the soot S1
．． Can blow away S2 instantly.

During this time, the solenoid valve 11 for supplying compressed air and the solenoid valve 12 for supplying ammonia water automatically stop supplying ammonia water because compressed air is working through the check valve 12a without having to take the trouble to close them. be done.

[Effects of the Invention] As described above, the present invention has the following excellent effects by having a simple configuration in which the solenoid valve 13 and the check valves 13a, 13a, 2a are added to the conventional one.

■Soot in the exhaust gas that has entered or adhered to the ammonia water spray nozzle is instantly removed by compressed air supplied via the solenoid valve for supplying cleaning air.

(2) Such cleaning can be carried out for a short period of time, for example, every 5 hours for 30 seconds, so although the supply of ammonia water is temporarily stopped during this period, this does not substantially interfere with the denitrification effect.

■Unlike conventional products, the complicated maintenance of removing the ammonia water spray nozzle from the ammonia mixing device and cleaning the soot is no longer necessary.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing one embodiment of the present invention, Fig. 2 is a longitudinal sectional front view showing the internal structure of an ammonia water spray nozzle, and Fig. 3 is a system diagram showing an embodiment of the present invention.
The figure is a system diagram showing the configuration of a denitrification device to which the ammonia water spray nozzle of the present invention is applied. , ammonia water spray nozzle 9, two inner tubes 10: outer tube 9a: ammonia water supply port 10a: compressed air supply port 11, compressed air solenoid valve 12, ammonia water solenoid valve 13: cleaning air supply solenoid valve 12a , Check valve 13a: Check valve Fig. 2

Claims (1)

[Claims] An ammonia water supply source is connected to the ammonia water supply source of the ammonia water spray nozzle through a check valve and a solenoid valve for ammonia water, and on the other hand, compressed air is connected to the compressed air supply port of the ammonia water spray nozzle. A compressed air source is connected through a solenoid valve for cleaning, and a solenoid valve for supplying cleaning air is further connected to an ammonia water supply port of the spray nozzle via a check valve, and the ammonia water spray nozzle A device for preventing blockage of an ammonia water spray nozzle in a denitrification device, characterized in that the solenoid valve for supplying cleaning air is periodically opened for a short period of time during operation.