JP2003286822A - Device and method for removing floating fine particulate in exhaust gas - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a removal device for fine particulates floating in exhaust gas which removes the floating fine particulates contained in the exhaust gas from an internal combustion engine such as a diesel engine or the like. <P>SOLUTION: The device is provided with a fine particulate removal device body 16 having a capture portion 13 mounted thereon which captures the floating fine particulates 12 by making the exhaust gas 11 (containing the floating fine particulates 12) pass therethrough, a front chamber 14 and a rear chamber 15, a discharge line 18 which discharges the cleaned-up exhaust gas 17 having passed through the capture portion 13, and a catalyst solution spray means 20 which sprays and adheres a catalyst solution 19 onto surfaces of the fine particulates 12 in the exhaust gas captured by the capture portion 13. The device is also provided with a bypass line 21 which lets the exhaust gas flow into the exhaust gas line 18 from the front chamber 14 of the capture portion 13 without making the exhaust gas pass through the capture portion 13 within the fine particulate removal device main body 16. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to suspended particulates (SP) contained in exhaust gas from an internal combustion engine such as a diesel engine for ships, land running, or stationary on land.
The present invention relates to an apparatus and method for removing suspended particles in exhaust gas for removing M).

[0002]

BACKGROUND ART Conventionally, in order to remove suspended fine particles (SPM, hereinafter also simply referred to as “fine particles”) contained in exhaust gas from a marine engine, a land traveling vehicle, a stationary stationary diesel engine or the like, a ceramic honeycomb is used. D by filter etc.
PF (Diesel Particulate Filter) has been proposed,
When particulates are collected in the DPF and the amount of deposition increases, the exhaust resistance increases, so this is burned and removed for regeneration.

As this regeneration method, the exhaust gas temperature is raised by a method of improving the exhaust temperature by throttling, a heater heating method, a reheating method, or the like,
The unburned portion of the collected fine particles was burned.

[0004]

However, the conventional method for decomposing fine particles has the following problems. (1) There is a problem that the honeycomb ceramic filter is damaged due to repeated thermal shocks during regeneration. (2) There is a problem in that the heat resistance and thermal shock resistance of the filter material are insufficient due to the occurrence of abnormal combustion, resulting in damage. (3) Utilities such as heater heating and reheating equipment and utility costs such as fuel are required, and there is a demand to reduce processing costs. (4) If the combustion is not sufficient, the pressure loss increases and it becomes unusable, so that the filter itself must be replaced.

In view of the above problems, the present invention provides an apparatus and method for removing suspended particulates in exhaust gas which can decompose suspended particulates in exhaust gas at low temperature without using conventional heating means such as a heater. The task is to do.

[0006]

The first invention of the present invention for solving the above-mentioned problems is a suspended particle removing apparatus for removing suspended particles in exhaust gas, wherein the exhaust gas is ventilated,
A main body of a fine particle removing device equipped with a front chamber and a rear chamber that incorporates a capturing unit for capturing the suspended particulates, an exhaust line for exhausting exhaust gas aerated through the capturing unit, and an exhaust gas captured by the capturing unit. In addition to being equipped with a catalyst adhering means for adhering the catalyst solution to the surface of the fine particles inside, a bypass line is provided to allow the exhaust gas to escape from the front chamber side of the trap portion to the exhaust gas line without passing through the trap portion in the main body of the fine particle removing device The present invention resides in a device for removing suspended particulates in exhaust gas.

In a second aspect based on the first aspect, the catalyst solution contains a catalyst containing at least one of an alkali metal and an alkaline earth metal, and the fine particles collected on the surface of the capturing section. Is catalytically burned when venting exhaust gas,
It is an apparatus for removing suspended particles characterized by removing the particles.

According to a third aspect of the present invention, in the first or second aspect of the invention, a discharge line for discharging the catalyst solution from the rear chamber side of the trap in the main body of the fine particle removing device, and a catalyst solution storage means for storing the catalyst solution. An apparatus for removing suspended particles is provided.

A fourth aspect of the invention is an apparatus for removing suspended particulates according to the third aspect of the invention, further comprising a feed line for feeding the catalyst solution from the catalyst solution storage means to the catalyst adhering means.

A fifth aspect of the present invention is the suspended particulate removing apparatus according to the third aspect of the present invention, characterized in that cooling means for cooling the catalyst solution in the catalyst solution storage means is provided.

A sixth aspect of the present invention is the suspended particulate removal apparatus according to the fourth aspect of the present invention, wherein a cooling fin is provided in the feed line to cool the catalyst solution.

A seventh aspect of the present invention is the suspended particulate removing apparatus according to the first aspect of the present invention, characterized in that a filter is provided in the rear chamber of the capturing section in the main body of the particulate removing apparatus to filter the catalyst solution. .

An eighth aspect of the present invention is the floating particulate matter removing apparatus according to the first aspect of the present invention, characterized in that a drain means is provided in the discharge line for discharging the exhaust gas from the main body of the particulate removing apparatus.

A ninth aspect of the present invention is the suspended particulate removing device according to the eighth aspect, further comprising a recovery line for recovering the catalyst solution storage means collected by the drain means.

According to a tenth aspect of the present invention, the apparatus for removing suspended particulates in exhaust gas according to any one of the first to ninth aspects is used, wherein a bypass line is opened when the exhaust gas is ventilated. On the way.

An eleventh aspect of the present invention uses the device for removing suspended particulates in exhaust gas according to any one of the first to ninth aspects, wherein a pressure difference between a front chamber and a rear chamber partitioned by a trap in the main body of the particulate removal device is provided. A method for removing suspended particulates in exhaust gas is characterized in that a bypass line for temporarily ventilating the exhaust gas is opened when the measured pressure exceeds a predetermined pressure difference.

A twelfth aspect of the present invention is an exhaust gas treatment system for purifying exhaust gas, which has a suspended particulate removal device according to any one of claims 1 to 9 which is interposed in an exhaust gas flue and decomposes suspended particulates in the exhaust gas. The exhaust gas treatment system is characterized by that.

A thirteenth invention is the twelfth invention, wherein
The exhaust gas treatment system is characterized in that it has a denitration device for decomposing nitrogen oxides in the exhaust gas on the upstream side or the downstream side of the fine particle removing device.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below, but the present invention is not limited thereto.

[First Embodiment] FIG. 1 is a schematic view of a device for removing suspended particles in exhaust gas according to the present embodiment. A suspended particulates removing device for removing suspended particulates in the exhaust gas (11), which is provided with a trap section (13) for ventilating the exhaust gas (including suspended particulates (12)) and capturing the suspended particulates (12). A fine particle removing device main body 16 having a rear chamber 15, an exhaust line 18 for exhausting the purified exhaust gas 17 that has permeated the capturing portion 13, and a catalyst on the surface 12 of the fine particles in the exhaust gas captured by the capturing portion 13. The exhaust gas line 1 is provided with catalyst solution spraying means 20 for spraying and adhering the solution 19 and from the front chamber 14 side of the trap 13 without passing through the trap 13 in the main body 16 of the fine particle removing device.
A bypass line 21 is provided to allow exhaust gas to escape to 8.

In the device for removing fine particles from exhaust gas according to the present embodiment, the fine particles 12 in the exhaust gas 11 are adhered by the capturing unit 13 and then captured after a predetermined time has elapsed or a pressure fluctuation has occurred. Catalyst solution 19 on the surface of fine particles
Is sprayed and adhered, the catalyst solution is dried, and then unburned fine particles are burned by exhaust heat of exhaust gas. In order to spray the catalyst, the catalyst solution 19 is sprayed from the ceiling portion of the main body of the suspended particulate removing apparatus in this embodiment.

In the present embodiment, when the catalyst liquid 19 is sprayed or when there is a pressure fluctuation between the front chamber 14 and the rear chamber 15, the bypass line 21 is opened and the trapping portion 13 is clogged. I try to prevent it.

Further, the sprayed catalyst solution 19 is recovered in the catalyst recovery tank 30 for reuse. In addition, a filter 22 is provided inside the rear chamber of the main body 16 of the fine particle removing device to filter the catalyst solution 19.

A cooling means 23 for supplying water to cool the catalyst solution 19 is provided in the catalyst recovery tank 30. This is because the catalyst solution 19 comes into contact with the capturing portion that collects the fine particles by passing the high-temperature exhaust gas, so that the temperature may be high. Further, the supply water 24 and the new catalyst solution 19 are supplied into the catalyst recovery tank 30 to adjust the catalyst concentration (for example, adjustment with a pH meter). Further, the catalyst residue 25 may be appropriately discarded from the bottom of the recovery tank.

As a method of cooling the catalyst, instead of the cooling means 23, a cooling means such as a cooling fin is provided around the supply pipe 26 for supplying the catalyst solution 19 to the catalyst solution spraying means 20 for spraying the catalyst solution. You may do it.

In the present invention, the catalyst solution means Na such as potassium carbonate and sodium carbonate, alkali metal such as K,
It is an aqueous solution containing at least one kind of alkaline earth metal. Further, seawater can be used as the alkali catalyst. Further, at least one kind of the above-mentioned alkali metal or alkaline earth metal may be contained in seawater.

In the present invention, by spraying the alkaline catalyst solution so as to cover the surface of the fine particles collected by the filter,
By impregnating and supporting the catalyst on the surface and inside of the fine particles, the catalyst can be uniformly arranged, and as a result, the combustion field can be made uniform, and the combustion temperature by the conventional heater (400 ° C or higher). It is possible to enable catalytic combustion on a lower temperature side (300 ° C. or lower) than the above. The heat source of the catalytic combustion uses high temperature exhaust gas.

Next, referring to FIG. 2, an outline of catalytic decomposition of the collected fine particles 12 will be described. As shown in FIG. 2, the surface of the collected suspended fine particles 12 is covered with the catalyst contained in the dropped water. afterwards,
The exhaust gas is aerated, the catalyst solution is dried, and the catalyst solution 19 also permeates the pores of the suspended fine particles 12. Next, the catalyst solution 19 that has penetrated into the inside is also dried, and the component exhibiting catalytic activity remains uniformly inside the fine particles. After that, exhaust gas 1
By causing 1 to flow in, catalytic combustion slowly proceeds at the temperature of the exhaust gas 11. Due to this catalytic combustion, the catalytic action works not only on the surface of the suspended fine particles 12 but also inside thereof, and the suspended fine particles 12 can be completely burned. In the above drying, instead of supplying exhaust gas, air or the like may be supplied to dry the catalyst component.

As a result, unburned components (soot, tar, etc.) in the fine particles can be decomposed in a low temperature region (eg, about 300 ° C.) without using a heater or the like as in the conventional case. Therefore, the suspended particulates 12 in the exhaust gas are collected and catalytically burned, so that they can be continuously treated, and the clean exhaust gas from which the particulates have been removed can be discharged.

In the present invention, the suspended particulates in the exhaust gas can be decomposed, so that the type of the internal combustion engine is not specified. For example, it is possible to decompose unburned particulate matter (SPM) contained in exhaust gas from internal combustion engines such as ships, land vehicles, stationary diesel engines, and generators at a low temperature. In addition to decomposing and removing suspended particulates in the exhaust gas discharged from an internal combustion engine, for example, from various incinerators such as municipal waste incinerators, industrial waste incinerators, sludge incinerators, pyrolysis furnaces, melting furnaces, etc. It is also possible to remove suspended particles in the exhaust gas.

[Second Embodiment] FIG. 3 is a schematic view of a device for removing suspended particulates in exhaust gas according to the present embodiment. A suspended particulates removing device for removing suspended particulates in exhaust gas, comprising a front chamber 14 and a rear chamber, which are provided with a trapping portion 13 for ventilating the exhaust gas (including suspended particulates 12) and capturing the suspended particulates 12. A fine particle removing device main body 1 including
6, a discharge line 18 for discharging the purified exhaust gas 17 aerated through the trap 13, and a catalyst solution spray for spraying and adhering the catalyst solution 19 on the surface 12 of the fine particles in the exhaust gas collected by the collector 13. Means 20 and a bypass line 30 for allowing exhaust gas to escape from the front chamber 14 side of the trap 13 to the exhaust gas line 18 without passing through the trap 13 in the main body 16 of the particulate remover; and the particulate remover. A water supply means 32 for supplying water 31 is provided in the main body 16.

By opening the bypass line 21, it is possible to deal with the clogging in the capturing unit 13, but the capturing unit 13
When the catalyst is deposited in (3), the catalyst deposited in the trap 13 can be dissolved by supplying the water 31 from the water supply means 32.

In particular, when the temperature of the capture unit 13 is high, the catalyst may be deposited when the catalyst solution 19 is rapidly sprayed, and this can be dealt with promptly.

Further, in the present embodiment, as shown in FIG. 3, a water tank 33 is provided, and water 31 is supplied from the water tank 33 to the inside of the apparatus main body 16 through the catalyst liquid supply pipe 26 by the supply pump 34. May be supplied.

[Third Embodiment] FIG. 4 is a schematic view of a device for removing suspended particles in exhaust gas according to the present embodiment. A suspended particulates removing device for removing suspended particulates in exhaust gas, comprising a front chamber 14 and a rear chamber, which are provided with a trapping portion 13 for ventilating the exhaust gas (including suspended particulates 12) and capturing the suspended particulates 12. A fine particle removing device main body 1 including
6, a discharge line 18 for discharging the purified exhaust gas 17 aerated through the trap 13, and a catalyst solution spray for spraying and adhering the catalyst solution 19 on the surface 12 of the fine particles in the exhaust gas collected by the collector 13. Means 20 and a bypass line 21 for allowing exhaust gas to escape from the front chamber 14 side of the trap 13 to the exhaust gas line 18 without passing through the trap 13 in the main body 16 of the particulate remover; and the particulate remover. The drain means 41 is provided in the discharge line 18 for discharging the exhaust gas from the main body 16.

The drain means 41 comprises a container body 43 having a partition plate 42 provided in the drain in the vertical direction and a drain discharge line 44.
By colliding 7 with the partition plate 42, a small amount of the catalyst solution 19 mixed in the exhaust gas can be separated. The separated catalyst solution 19 is returned to the catalyst recovery tank 30 via the drain discharge line 44.

When ammonia denitration means is provided on the upstream side of the catalyst removing device, ammonium hydrogensulfate (NH ₄ HSO ₃ ) is changed by the ammonia used for denitration.
However, this ammonium sulfate can also be separated by the drain means 41. This ammonium sulfate neutralizes the catalyst solution 19 in the catalyst recovery tank, but this should be eliminated by monitoring the catalyst solution with a pH meter or the like and supplementing with a new catalyst as necessary. Good.

In order to prevent ammonium sulfate from depositing in the pipe, the exhaust gas line 18 from the fine particle removing device to the drain means 41 is kept at a high temperature (200 ° C. or higher) to prevent the deposit. It should be positively dropped at 41.

A cooling means for cooling the drain means 41 may be provided to improve the drain collection efficiency.

Purified exhaust gas 17 from which fine particles have been removed
A laminated body such as a wire mesh may be provided in place of the partition plate 41 that causes the partition plate 42 to collide with the partition plate 42. Further, the partition plate 41 is provided with a plurality of pores, and the partition plates 41 are arranged so that the pores are staggered. May be laminated so as to be orthogonal to the vertical axis direction and the gas flow path may be changed to improve the drain collection efficiency.

[0041]

As described above, according to the present invention,
When spraying the catalyst liquid or when there is a pressure change between the front chamber and the rear chamber, the bypass line is opened to prevent clogging of the trap portion.

Further, since water is supplied into the fine particle removing device, the catalyst can be dissolved in the case where the catalyst is deposited in the capturing section.

Further, since the drain means is provided in the discharge line for discharging the exhaust gas from the main body of the fine particle removing apparatus, it is possible to separate a minute amount of the catalyst solution mixed in the purified exhaust gas from which the fine particles have been removed. The separated catalyst solution can be reused.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an apparatus for removing suspended particles according to a first embodiment.

FIG. 2 is a schematic diagram showing a state in which suspended particulates are coated with a catalyst liquid.

FIG. 3 is a schematic view of a suspended particle removing apparatus according to a second embodiment.

FIG. 4 is a schematic view of a suspended particle removing device according to a third embodiment.

[Explanation of symbols]

11 exhaust gas 12 suspended particles 13 Capture Department 14 anteroom 15 Rear room 16 Particle removal device body 17 Purified exhaust gas 18 discharge line 19 Catalyst solution 20 catalyst solution spraying means 21 Recovery tank 22 filters 23 Cooling means 24 Supply water 25 residue 26 Supply piping 30 recovery tank 31 water 32 Water supply means 33 water tank 34 Supply pump 41 Drain means

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B01D 47/06 F01N 3/04 D 4D064 53/94 3/18 F F01N 3/04 B01D 53/36 104B 3/18 35 / 14 101 (72) Inventor Yuichi Fujioka 5-717-1, Fukahori-cho, Nagasaki-shi, Nagasaki Sanhishi Heavy Industries Ltd. Nagasaki Research Institute (72) Inventor, Yukihiro Abe 3000, Tana, Sagamihara, Kanagawa Mitsubishi Heavy Industries, Ltd. General-purpose machine / special vehicle business headquarters (72) Inventor Yuji Oda 5-717-1, Fukahori-cho, Nagasaki-shi, Nagasaki Sanryo Heavy Industries Co., Ltd. Nagasaki Research Institute (72) Inventor Hiroyuki Endo 5-chome, Fukahori-cho, Nagasaki-shi, Nagasaki No. 717-1 Sanryishi Heavy Industries Co., Ltd. Nagasaki Research Laboratory F-term (reference) 3G090 AA01 AA06 BA08 CB22 3G091 AA02 AA04 AA06 AA18 AB01 AB13 AB15 BA07 CA12 CA15 GB02W GB03W HA14 HB03 4D031 AB02 AB23 BA03 BA07 BB04 DA01 DA04 A01 EA01 4A03 BA06 BB07 DA10 4D048 AA14 AA18 AB01 BA01Y BA02Y BA14Y BA15Y CC26 CC4 1 DA01 DA02 DA07 DA20 EA08 4D064 AA40 BK05 DE01

Claims (13)

[Claims] 1. A suspended particulates removing apparatus for removing suspended particulates in exhaust gas, which comprises a front chamber and a rear chamber in which a trapping unit for ventilating the exhaust gas and capturing the suspended particulates is installed. The apparatus includes a main body of a removing device, an exhaust line for exhausting the exhaust gas ventilated through the trapping section, and a catalyst adhering means for adhering a catalyst solution to the surface of the fine particles in the exhaust gas trapped by the trapping section. A device for removing suspended particulates in exhaust gas, comprising a bypass line for allowing exhaust gas to escape from the front chamber side of the capture unit to the exhaust gas line without passing through the capture unit in the apparatus body. 2. The catalyst solution according to claim 1, wherein the catalyst solution contains a catalyst containing at least one kind of alkali metal or alkaline earth metal, and the fine particles trapped on the surface of the trapping part are used as a catalyst when ventilating exhaust gas. A device for removing suspended particles characterized by burning and removing. 3. The discharge line for discharging the catalyst solution from the rear chamber side of the capturing section in the main body of the fine particle removing apparatus according to claim 1, and a catalyst solution storing means for storing the catalyst solution. A device for removing suspended particulates. 4. The suspended particle removing device according to claim 3, further comprising a feed line for feeding the catalyst solution from the catalyst solution storage means to the catalyst adhering means. 5. The suspended particulates removing device according to claim 3, further comprising a cooling means for cooling the catalyst solution in the catalyst solution storage means. 6. The suspended particle removing device according to claim 4, wherein a cooling fin is provided in the feeding line to cool the catalyst solution. 7. The suspended particulates removing apparatus according to claim 1, wherein a filter is provided in the rear chamber of the capturing section in the particulates removing apparatus main body to filter the catalyst solution. 8. The suspended particulates removing apparatus according to claim 1, wherein a drain means is provided in an exhaust line for exhausting the exhaust gas from the particulates removing apparatus main body. 9. The suspended particulate removal device according to claim 8, further comprising a recovery line for recovering the catalyst solution storage means collected by the drain means. 10. A method for removing suspended particulates in exhaust gas, which comprises using the apparatus for removing suspended particulates in exhaust gas according to claim 1 and opening a bypass line when ventilating the exhaust gas. 11. A device for removing suspended particulates in exhaust gas according to claim 1, wherein a pressure difference between a front chamber and a rear chamber partitioned by a trap in the body of the particulate removal device is measured.
A method for removing suspended particulates in exhaust gas, which comprises opening a bypass line for temporarily venting exhaust gas when a pressure difference exceeds a predetermined value. 12. An exhaust gas treatment system for purifying exhaust gas, comprising the suspended particle removing device according to claim 1, which is installed in a flue of the exhaust gas and decomposes suspended particles in the exhaust gas. Exhaust gas treatment system. 13. The exhaust gas treatment system according to claim 12, further comprising a denitration device for decomposing nitrogen oxides in the exhaust gas, on the upstream side or the downstream side of the fine particle removing device.