JPH06146853A - Exhaust gas treatment device - Google Patents

Abstract

PURPOSE:To improve the washing efficiency of a back wash mechanism in an exhaust gas treatment device. CONSTITUTION:In an exhaust gas treatment device formed by arranging one or a plurality of pipe shaped back wash nozzle (s) 42 for injecting washing gas to the part of the flow-out passage side of a filter 30 in a casing 12, a closing chamber (R) is formed on a part the flow-out passage side of the filter 30 to be existent in the flow-out passage per back wash of the filter 30, and also direction cross with injection direction of washing gas in the closing chamber (R) is opened to an opening part 44b. It is, thus possible to lead washing gas to the filter with a high efficiency, and also reduce flow-out resistance of treatment completed gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas treatment device.

[0002]

2. Description of the Related Art An exhaust gas treating apparatus for collecting dust in exhaust gas discharged from engines of various vehicles, ships, industrial machines, etc. and discharging it as clean gas is disclosed in Japanese Patent Application Laid-Open No.
As described in Japanese Patent No. 159408, a large number of inner holes having one end side plugged and the other end side open and a large number of inner holes having the other end side plugged and one end side open are provided. Exhaust gas in which a filter having a filter element, one of which forms an inflow passage of a gas to be treated and the other of which forms an outflow passage of a treated gas, is arranged in a portion between a gas inflow hole and a gas outflow hole in a casing. There is a processing device. In the exhaust gas treatment apparatus of this type, in order to regenerate the filter that collects dust in the exhaust gas, a pipe-shaped backwash nozzle for ejecting a cleaning gas is arranged at a portion on the outflow passage side of the filter in the casing. A means is provided for intermittently ejecting the cleaning gas for each backwashing unit of the filter and supplying it to the outflow passage of the filter to remove the dust adhering to the filter.

[0003]

By the way, in the exhaust gas treating apparatus of this type, since the means for backwashing during the exhaust gas treatment is adopted, the cleaning gas ejected from the backwash nozzle is discharged from the filter. The outflowing treated gas scatters in the outflow direction (downstream side) and the supply amount into the outflow passage of the filter decreases, so that the backwashing efficiency of the filter is low and the cleaning gas cannot be effectively used. In order to enhance the backwashing effect of the filter, a means for increasing the jetting amount of the cleaning gas can be considered, but if this means is adopted, the operating cost will increase. Further, a means for narrowing the outflow hole of the treated gas in the casing in order to prevent the cleaning gas from scattering to the downstream side is conceivable. However, when this means is adopted, the outflow resistance of the treated gas increases. There is. Therefore, an object of the present invention is to effectively use the cleaning gas without increasing the outflow resistance of the treated gas and to improve the backwash efficiency of the filter.

[0004]

DISCLOSURE OF THE INVENTION The present invention has a large number of inner holes which are plugged at one end and open at the other end and a large number of inner holes which are plugged at the other end and open at the one end. A filter having one or a plurality of filter elements, one of which forms an inflow passage of the gas to be treated and the other of which forms an outflow passage of the treated gas, is provided in the casing between the gas inflow hole and the gas outflow hole. In the exhaust gas treatment device, which is provided with one or a plurality of pipe-shaped backwash nozzles for injecting a cleaning gas into a portion on the outflow passage side of the filter in the casing, the outflow passage side of the filter is provided. The outflow passage forms a closed chamber facing each backwash unit of the filter, the backwash nozzle faces the closed chamber, and is orthogonal to the jet direction of the backwash gas in the closed chamber. It is characterized in that the opening direction.

[0005]

In the exhaust gas treating apparatus constructed as described above, the backwashing gas is ejected from the backwashing nozzle and supplied into the outflow passage of each backwashing unit of the filter, and adheres to the inner wall of the filter. Remove the dust and backwash the filter. In this case, the backwashing gas is ejected into the closed chamber surrounded by the air and is prevented from scattering, so that it is efficiently supplied into the outflow passage of the filter to enhance the washing efficiency and effectively use the washing gas. Is planned. Further, in the closed chamber, the direction orthogonal to the jet direction of the backwash gas is open, so this open portion functions as an outlet for the treated gas, and the outflow resistance of the treated gas does not increase. .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 shows an entire high temperature exhaust gas treatment apparatus which is an exhaust gas treatment apparatus according to an embodiment of the present invention, and FIG. The main part of the exhaust gas treatment device is shown. The exhaust gas treatment device treats exhaust gas of a diesel engine generated in a factory or the like, and a plurality of the exhaust gas treatment devices are arranged in series in the front-rear direction, and are arranged in parallel in two rows on the left and right. It is one of a large number of exhaust gas treatment devices that compose. The exhaust gas treatment device basically has the same configuration as the exhaust gas treatment device disclosed in the specification of Japanese Patent Application No. 3-53780 filed by the present applicant, except for a part of the backwash mechanism.
A hopper 1 that includes a casing 10, a combustion furnace 20, a filter 30, and a backwash mechanism 40 and that constitutes the casing 10.
1 is a supply duct 5 for supplying an exhaust gas as a gas to be treated
1 is connected, and an exhaust duct 52 for exhausting a clean gas that is a treated gas is connected to the can body 12 that constitutes the casing 10.

The combustion furnace 20 is arranged at the lower end of the hopper 11, and the lower end opening of the hopper 11 faces the upper inside. The combustion furnace 20 has a heater 2 at the bottom of the furnace body 21.
2, the dust collected and separated by the filter 30 falls into the furnace body 21, and the combustible material in the accumulated dust is burned by the action of the heater. Further, the filter 3 is provided in the can body 12 of the casing 10.
0 and a backwash mechanism 40 are provided.

The filter 30, as shown in FIGS.
16 filter elements 31 are arranged in parallel, and each filter element 31 includes a pair of side plates 32, 33.
Are clamped and pinched by the first support member 34 at the lower end and the second support member 35 at the upper end.
And is disposed inside the can body 12. The filter element 31 is made of a porous ceramic and has a quadrangular shape, and has a honeycomb structure as shown in FIG. 5, and has a large number of inner holes 31a and 31b arranged in parallel with each other. In the filter element 31, the lower end side corresponds to the upstream side of the gas flow and the upper end side corresponds to the downstream side of the gas flow, and one of the inner holes 31a and 31b is plugged. The other opening is open.

In the filter element 31, the inner holes are basically plugged in checkered openings on the upstream side and the downstream side, and exceptionally, the openings at the corners of the filter element 31 are exceptional. Has also been made.
Therefore, the group of each inner hole 31a is plugged on the downstream side and is open on the upstream side to form an inflow passage for the gas to be treated, and the group of each inner hole 31b is plugged on the upstream side and opened on the downstream side. And forms an outflow passage for the treated gas. In addition, the partition wall that divides the inner holes 31a and 31b has a filter function, and the fine particles in the gas to be processed pass through the partition wall and flow from the inner holes 31a to the inner holes 31b. It is collected on the inner wall surface of the hole 31a.

Each of the side plates 32, 33 has an L-shaped cross section, one side 32a, 33a of which is longer than the total side of the four filter elements 31 by a predetermined length, and the other side 32b, 33b thereof. The filter element 31 is formed to have substantially the same length as the total of the other sides, and is formed to be longer than the height of each filter element 31 by a predetermined length. The outer periphery of each filter element 31 is a sealing member 36.
It is arranged in parallel in the same number in the vertical and horizontal directions while being surrounded by a and 36b, and is clamped and clamped from the outer periphery by both side plates 32 and 33. Each of the seal members 36a and 36b is made of ceramic fibers hardened into a sheet shape and has excellent heat resistance and a predetermined elastic force.

In the exhaust gas treating apparatus, the exhaust gas to be treated is supplied from the supply duct 51 into the hopper 11 of the casing 10, and the supplied exhaust gas is introduced into the inner holes 31a of the filter elements 31 of the ceramic filter 30. Inflow, permeation through each partition wall, inflow into each inner hole 31b, outflow from the opening of the inner hole 31b, and can 1
It is discharged from inside 2 through the discharge duct 52. During this time, the dust in the exhaust gas is collected on the inner wall surface of each inner hole 31a, and high pressure air is intermittently ejected from the nozzle 41 of the backwash mechanism 40 described later, so that each inner hole 31b of each filter element 31 is ejected. Dust that has been supplied into the interior and collected on the inner wall surface is released. The separated dust falls through the hopper 11 into the combustion furnace 20 and is deposited, and combustible substances in the deposit are burned by the action of the heater 22.

Therefore, the backwash mechanism 40 is shown in FIGS.
As shown in FIG. 4, a compressed air supply source 41 (compressed air supply source), a plurality of pipe-shaped nozzles 42, and each nozzle 42 are connected to the compressed air supply source 4.
It is provided with a connecting pipe 43 and a cover body 44 which are connected to 1. The cover body 44 covers the entire downstream side of all the filter elements 31 constituting the ceramic filter 30, and is arranged on the second support member 35. Cover body 4
4 includes a plurality of closed chambers R that extend in the left-right direction in the drawing and are partitioned in the front-back direction, and the number of each closed chamber R corresponds to the number of filter elements 31 arranged in parallel in the front-rear direction.
Therefore, the downstream end portions of the filter elements 31 arranged in parallel in the left-right direction face the closed chambers R. The cover body 44 is provided with an opening 44b on the right side of the main body 44a in the figure, and the opening 44b opens the right side end of each closed chamber R in the figure in the can 12. Each nozzle 42 penetrates into each closed chamber R, and the ejection hole portion of each nozzle 42 faces the downstream end of each filter element 31.

In the exhaust gas treatment apparatus, the compressed air is selectively ejected from each nozzle 42 at regular time intervals by the opening / closing control of the solenoid valve 45 during the exhaust gas treatment operation to form the outflow passage of each filter element 31. It is supplied into the inner hole 31b. As a result, the dust adhering to the wall surface of the inner hole 31a separates, and falls through the hopper 11 and into the furnace body 21 of the combustion furnace 20. The dust that has fallen off accumulates in the furnace body 21, and the combustibles therein burn by the action of the heater 22.

By the way, in the exhaust gas treating apparatus, compressed air is jetted from the nozzle 42 to be supplied into the inner hole 31b forming the outflow passage of each backwash unit of the filter element 31 constituting the ceramic filter 30, and the filter is filtered. The dust adhering to the wall surface of the inner hole 31a of the element 31 is removed to backwash the filter element 31. In this case, the compressed air is jetted into each closed chamber R surrounded by the air and is prevented from scattering, so that the filter element 31
It is efficiently supplied into the inner hole 31b of No. 1 to enhance the cleaning efficiency, and the compressed air is effectively used. Further, in each of the closed chambers R, a direction orthogonal to the jetting direction of the compressed air is opened by the opening 44b, so that the opening 44b functions as an outlet for the treated gas and the outflow resistance of the treated gas. Does not increase.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an exhaust gas treating apparatus according to an embodiment of the present invention.

FIG. 2 is a secondary cross-sectional view showing a main part of the exhaust gas treating apparatus.

FIG. 3 is a vertical cross-sectional view of a ceramic filter that constitutes the exhaust gas treating apparatus.

FIG. 4 is a plan view of the ceramic filter.

FIG. 5 is a partial plan view (a) of an upstream end surface and a partial plan view (b) of a downstream end surface of a filter element constituting the ceramic filter.

[Explanation of symbols]

10 ... Casing, 12 ... Can body, 20 ... Combustion furnace, 30 ...
Ceramic filter, 31 ... Filter element, 31
a, 31b ... inner hole, 40 ... backwashing mechanism, 41 ... compressed air source, 4
2 ... Nozzle, 44 ... Cover body, 44a ... Main body of cover body, 44b ... Opening portion, R ... Closed chamber.

Claims (1)

[Claims] 1. A large number of inner holes having one end side plugged and the other end side open, and a plurality of inner holes having the other end side plugged and one end side open, one of these inner holes being for gas to be treated. A filter having one or a plurality of filter elements, which form an inflow path and the other forms an outflow path for the treated gas, is arranged in a portion of the casing between the gas inflow hole and the gas outflow hole, and In the exhaust gas treating apparatus in which one or a plurality of pipe-shaped backwash nozzles for ejecting the cleaning gas are disposed at the outlet side portion of the filter, the outlet passage is provided at the outlet side portion of the filter. The backwash nozzle is formed in the closed chamber facing each backwash unit, and the direction orthogonal to the jet direction of the backwash gas in the closed chamber is opened. Exhaust gas treatment apparatus.