JP4215994B2 - Apparatus and method for removing suspended particulate matter in exhaust gas - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and a method for removing suspended particulates in exhaust gas for removing suspended particulates (SPM) contained in exhaust gas from, for example, an internal combustion engine such as a diesel engine, for example, for marine use, for land travel, and stationary on land.
[0002]
[Background]
Conventionally, in order to remove suspended particulates (SPM, hereinafter also simply referred to as “particulates”) contained in exhaust gas from marine, onshore, and stationary diesel engines, a DPF using a ceramic honeycomb filter or the like is used. (Diesel Particulate Filter) has been proposed. Fine particles are collected in the DPF, and the exhaust resistance increases as the amount of deposition increases.
[0003]
As this regeneration method, the exhaust gas temperature is increased by a method of improving the exhaust temperature by throttling, a heater heating method, or a reheating method, and the unburned portion in the collected particulates is burned.
[0004]
[Problems to be solved by the invention]
However, the conventional fine particle decomposition method has the following problems.
(1) There is a problem that the honeycomb ceramic filter is damaged due to repeated thermal shocks during regeneration.
(2) Due to abnormal combustion, there is a problem that the heat resistance and thermal shock resistance of the filter material are insufficient and damage occurs.
(3) There is a need to reduce the processing cost because utility costs such as heater heating and reheating equipment and fuel are necessary.
(4) If the combustion is not enough, the pressure loss will increase and it will become unusable, and as a result, the filter itself needs to be replaced.
[0005]
In view of the above problems, the present invention provides an apparatus and method for removing suspended particulates in exhaust gas that can decompose suspended particulates in exhaust gas at low temperatures without using a heating means such as a conventional heater. Let it be an issue.
[0006]
[Means for Solving the Problems]
The first invention of the present invention for solving the above-mentioned problems is
A suspended particulate removal device for removing suspended particulates in exhaust gas,
A fine particle removing apparatus main body having a front chamber and a rear chamber with a trapping section for trapping the floating fine particles by aeration of the exhaust gas;
An exhaust gas line for exhausting the exhaust gas that has passed through the capture unit;
Catalyst attachment means for attaching a catalyst solution to the surface of fine particles in the exhaust gas collected by the collection unit ;
A bypass line for releasing exhaust gas from the front chamber side of the no capture portion to the exhaust gas line to pass through the capturing portion in the particulate filter body,
A discharge line for discharging the catalyst solution from the rear chamber side of the capture unit in the fine particle removing device main body,
A catalyst solution storage means for storing the catalyst solution;
An apparatus for removing suspended particulate matter in exhaust gas, comprising cooling means for cooling the catalyst solution in the catalyst solution storage means .
[0007]
According to a second invention, in the first invention,
The catalyst solution contains a catalyst containing at least one kind of alkali metal or alkaline earth metal, and the fine particles collected on the surface of the trapping part are catalytically burned and removed when the exhaust gas is vented. It is in a device for removing suspended particulate matter in exhaust gas .
[0009]
According to a third invention, in the first or second invention,
An apparatus for removing suspended particulate matter in exhaust gas , characterized in that a supply line for supplying the catalyst solution from the catalyst solution storage means to the catalyst adhesion means is provided.
[0011]
According to a fourth invention, in the third invention,
The present invention provides an apparatus for removing suspended fine particles in exhaust gas, wherein a cooling fin is provided in the supply line to cool the catalyst solution.
[0012]
According to a fifth invention, in the first invention,
In the apparatus for removing suspended particulate matter in exhaust gas, a filter is provided in the rear chamber of the trapping part in the particulate matter removing apparatus main body, and the catalyst solution is filtered.
[0013]
According to a sixth invention, in the first invention,
A floating particulate filter in the exhaust gas, characterized in that a drainage means to the exhaust gas line.
[0014]
A seventh invention is the sixth invention, wherein
The catalyst solution separated in the drain means in a floating particulate filter in the exhaust gas, characterized in that a recovery line for recovering the said catalyst solution storage means.
[0015]
An eighth invention is a method for removing suspended particulate matter in exhaust gas, wherein the suspended particulate removing device in exhaust gas according to any one of 1 to 7 is used, and a bypass line is opened when the exhaust gas is ventilated. .
[0016]
The ninth invention uses the suspended particulate removal device in the exhaust gas according to any one of the first to seventh , measures the pressure difference between the front chamber and the rear chamber partitioned by the capture unit in the particulate removal device body, In the method for removing suspended particulate matter in the exhaust gas, the bypass line for temporarily venting the exhaust gas is opened when the pressure difference becomes equal to or greater than a predetermined pressure difference.
[0017]
The tenth invention is an exhaust gas treatment system for purifying exhaust gas,
An exhaust gas treatment system comprising the apparatus for removing suspended particulate matter in exhaust gas according to claims 1 to 7 , which is disposed in an exhaust gas flue and decomposes suspended particulates in the exhaust gas .
[0018]
In an eleventh aspect based on the tenth aspect ,
In the exhaust gas treatment system, a denitration device that decomposes nitrogen oxides in the exhaust gas is provided on the upstream side or the downstream side of the apparatus for removing suspended particulates in the exhaust gas.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, although embodiment of this invention is described, this invention is not limited to this.
[0020]
[First Embodiment]
FIG. 1 is a schematic diagram of an apparatus for removing suspended particulate matter in exhaust gas according to the present embodiment. An apparatus for removing suspended particles in the exhaust gas 11, wherein the exhaust gas (including the suspended particles 12) 11 is vented and a capture unit 13 for capturing the suspended particles 12 is provided, and the front chamber 14. A fine particle removing device main body 16 having a rear chamber 15, an exhaust gas line 18 for discharging the purified exhaust gas 17 that has passed through the capture unit 13, and a catalyst on the surface 12 of the particulates in the exhaust gas collected by the collection unit 13. A catalyst solution spraying means 20 for spraying and adhering the solution 19 is provided, and the exhaust gas is discharged from the front chamber 14 side of the capture unit 13 to the exhaust gas line 18 without passing through the capture unit 13 in the fine particle removing device main body 16. Is provided with a bypass line 21.
[0021]
In the particulate matter removing apparatus in the exhaust gas according to the present embodiment, the particulate matter 12 in the exhaust gas 11 is adhered by the capturing unit 13 and then after a predetermined time has elapsed or after a pressure fluctuation occurs, After the catalyst solution 19 is sprayed and adhered, the catalyst solution is dried, and then the unburned fine particles are burned by the exhaust heat of the exhaust gas.
In order to spray the catalyst, in the present embodiment, the catalyst solution 19 is sprayed from the ceiling of the floating particulate removing device main body.
[0022]
In the present embodiment, when the catalyst solution 19 is sprayed or when pressure fluctuation occurs between the front chamber 14 and the rear chamber 15, the bypass line 21 is opened to prevent clogging of the capture unit 13. I am doing so.
[0023]
The sprayed catalyst solution 19 is recovered in the catalyst recovery tank 30 and is reused.
Further, a filter 22 is provided in the rear chamber of the fine particle removing device main body 16 so as to filter the catalyst solution 19.
[0024]
The catalyst recovery tank 30 is provided with cooling means 23 for supplying water to cool the catalyst solution 19. This is because the catalyst solution 19 comes into contact with the capture part that has passed the high-temperature exhaust gas to collect the fine particles, which may result in a high temperature.
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 or the like).
Further, the catalyst residue 25 may be appropriately discarded from the bottom of the recovery tank.
[0025]
As a method for cooling the catalyst, instead of the cooling means 23, cooling means such as cooling fins are provided around the supply pipe 26 of the catalyst solution 19 up to the catalyst solution spraying means 20 for spraying the catalyst solution. Also good.
[0026]
Here, the catalyst solution in the present invention is an aqueous solution containing at least one of alkali metals such as Na and K such as potassium carbonate and sodium carbonate, and alkaline earth metals. Seawater can also be used as an alkali catalyst. Moreover, you may make it contain at least 1 sort (s) of the said alkali metal or alkaline-earth metal in seawater.
[0027]
In the present invention, by spraying the alkali catalyst solution so as to cover the surface of the fine particles collected by the filter, the catalyst can be uniformly disposed by impregnating and supporting the surface of the fine particles and the inside thereof, As a result, the combustion field can be made uniform, and catalytic combustion can be performed on the lower temperature side (300 ° C. or lower) than the combustion temperature (400 ° C. or higher) by a conventional heater or the like.
A high temperature exhaust gas is used as a heat source for the catalytic combustion.
[0028]
Next, the outline of catalytic decomposition of the collected fine particles 12 will be described with reference to FIG.
As shown in FIG. 2, the surface of the collected suspended fine particles 12 is covered with a catalyst contained in the falling water.
Thereafter, the exhaust gas is vented, the catalyst solution is dried, and the catalyst solution 19 penetrates into the pores of the suspended fine particles 12.
Next, the catalyst solution 19 that has penetrated into the interior is also dried, and a component that exhibits catalytic activity remains uniformly within the fine particles.
After that, by causing the exhaust gas 11 to flow, catalytic combustion proceeds slowly 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 addition, the said drying may supply air etc. instead of supplying exhaust gas, and you may make it dry a catalyst component.
[0029]
As a result, unburned components (soot, tar, etc.) in the fine particles can be decomposed in the low temperature region (for example, about 300 ° C.) without using a heater or the like as in the prior art. Therefore, since the suspended fine particles 12 in the exhaust gas are collected and subjected to catalytic combustion, they can be processed continuously, and the clean exhaust gas from which the fine particles have been removed can be discharged.
[0030]
In the present invention, since the suspended particulates in the exhaust gas can be decomposed, the type of the internal combustion engine is not specified at all.
For example, the unburned particulate matter (SPM) contained in the exhaust gas from an internal combustion engine such as a marine vessel, on-shore vehicle, or stationary diesel or generator can be decomposed at a low temperature. In addition to decomposing and removing suspended particulates in exhaust gas discharged from internal combustion engines, for example, from various incinerators such as municipal waste incinerators, industrial waste incinerators, sludge incinerators, pyrolysis furnaces, melting furnaces, etc. Airborne particulates in the exhaust gas can also be removed.
[0031]
[Second Embodiment]
FIG. 3 is a schematic diagram of an apparatus for removing suspended particulate matter in exhaust gas according to the present embodiment. An apparatus for removing suspended particulates in exhaust gas, wherein the exhaust chamber (including suspended particulates 12) is vented and a capture unit 13 for capturing the suspended particulates 12 is provided, and a front chamber 14 and a rear chamber 15, the exhaust gas line 18 for exhausting the purified exhaust gas 17 that has passed through the capture unit 13, and the catalyst solution 19 on the surface 12 of the particulates in the exhaust gas collected by the collection unit 13. And a catalyst solution spraying means 20 for spraying and adhering to the exhaust gas, and let the exhaust gas escape from the front chamber 14 side of the capture unit 13 to the exhaust gas line 18 without passing through the capture unit 13 in the fine particle removing device main body 16. A bypass line 21 and water supply means 32 for supplying water 31 into the fine particle removing device main body 16 are provided.
[0032]
The opening of the bypass line 21 can cope with clogging in the capture unit 13, but when there is catalyst deposition in the capture unit 13, the water 31 is supplied from the water supply means 32 to capture the catalyst. The catalyst deposited in the part 13 can be dissolved.
[0033]
In particular, when the temperature of the capture unit 13 is high, the catalyst may be deposited when the catalyst solution 19 is sprayed rapidly, and this can be dealt with quickly.
[0034]
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 into the apparatus main body 16 via the catalyst solution supply pipe 26 by the supply pump 34. You may do it.
[0035]
[Third Embodiment]
FIG. 4 is a schematic diagram of an apparatus for removing suspended particulate matter in exhaust gas according to the present embodiment. An apparatus for removing suspended particulates in exhaust gas, wherein the exhaust chamber (including suspended particulates 12) is vented and a capture unit 13 for capturing the suspended particulates 12 is provided, and a front chamber 14 and a rear chamber 15, the exhaust gas line 18 for exhausting the purified exhaust gas 17 that has passed through the capture unit 13, and the catalyst solution 19 on the surface 12 of the particulates in the exhaust gas collected by the collection unit 13. And a catalyst solution spraying means 20 for spraying and adhering to the exhaust gas, and let the exhaust gas escape from the front chamber 14 side of the capture unit 13 to the exhaust gas line 18 without passing through the capture unit 13 in the fine particle removing device main body 16. The drain means 41 is provided in the bypass line 21 and the exhaust gas line 18 that exhausts exhaust gas from the fine particle removing device main body 16.
[0036]
The drain means 41 is composed of a container main body 43 provided with a partition plate 42 in the drain in the vertical direction and a drain discharge line 44, and the purified exhaust gas 17 from which fine particles have been removed collides with the partition plate 42, thereby A small amount of the mixed catalyst solution 19 can be separated. The separated catalyst solution 19 is returned to the catalyst recovery tank 30 via the drain discharge line 44.
[0037]
When ammonia denitration means is provided on the upstream side of the catalyst removal apparatus, ammonium hydrogen sulfate (NH ₄ HSO ₃ ) may be contained in the ammonia used for denitration. This ammonium sulfate is also included in the drain means 41. Can be separated. This ammonium sulfate will neutralize the catalyst solution 19 in the catalyst recovery tank, but this problem can be solved by monitoring the catalyst solution with a pH meter or the like and replenishing a new catalyst as necessary. That's fine.
[0038]
Further, in order to prevent precipitation of ammonium sulfate 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 precipitation, and the drain means 41 actively Just drop it.
[0039]
Further, a cooling means for cooling the drain means 41 may be provided to improve drain collecting efficiency.
[0040]
In addition, a laminated body such as a wire mesh may be provided instead of the partition plate 42 with which the purified exhaust gas 17 from which the fine particles have been removed is collided. Furthermore, the partition plate 42 is provided with a plurality of pores, and the pores are staggered. As described above, the drain collecting efficiency may be improved by stacking a plurality of partition plates 42 so as to be orthogonal to the vertical axis direction and changing the gas flow path.
[0041]
【The invention's effect】
As described above, according to the present invention, when the catalyst solution is sprayed or when there is a pressure fluctuation between the front chamber and the rear chamber, the bypass line is opened to clog the capture unit. I try to prevent it.
[0042]
In addition, since water is supplied into the fine particle removing device, the catalyst can be dissolved when the catalyst is deposited in the capturing unit.
[0043]
Furthermore, since the drain means is provided in the exhaust gas line that exhausts the exhaust gas from the main body of the fine particle removing device, it is possible to separate a trace amount of 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 the drawings]
FIG. 1 is a schematic view of an apparatus for removing suspended particulates according to a first embodiment.
FIG. 2 is a schematic view showing a state in which suspended fine particles are coated with a catalyst solution.
FIG. 3 is a schematic view of a suspended particulate removal apparatus according to a second embodiment.
FIG. 4 is a schematic view of a suspended particulate removal apparatus according to a third embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Exhaust gas 12 Floating particulate 13 Capture part 14 Front chamber 15 Rear chamber 16 Fine particle removal apparatus main body 17 Purified exhaust gas 18 Exhaust gas line 19 Catalyst solution 20 Catalyst solution spraying means 21 Recovery tank 22 Filter 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

Claims (11)

A suspended particulate removal device for removing suspended particulates in exhaust gas,
A fine particle removing apparatus main body having a front chamber and a rear chamber with a trapping section for trapping the floating fine particles by aeration of the exhaust gas;
An exhaust gas line for exhausting the exhaust gas that has passed through the capture unit;
Catalyst attachment means for attaching a catalyst solution to the surface of fine particles in the exhaust gas collected by the collection unit ;
A bypass line for releasing exhaust gas from the front chamber side of the no capture portion to the exhaust gas line to pass through the capturing portion in the particulate filter body,
A discharge line for discharging the catalyst solution from the rear chamber side of the capture unit in the fine particle removing device main body,
A catalyst solution storage means for storing the catalyst solution;
An apparatus for removing suspended particulate matter in exhaust gas, comprising: cooling means for cooling the catalyst solution in the catalyst solution storage means . In claim 1,
The catalyst solution contains a catalyst containing at least one kind of alkali metal or alkaline earth metal, and the fine particles collected on the surface of the trapping part are catalytically burned and removed when the exhaust gas is vented. Equipment for removing suspended particulate matter in exhaust gas . In claim 1 or claim 2 ,
An apparatus for removing suspended particulate matter in exhaust gas, comprising a supply line for supplying the catalyst solution from the catalyst solution storage means to the catalyst adhesion means. In claim 3 ,
An apparatus for removing suspended particulate matter in exhaust gas, wherein the supply line is provided with cooling fins to cool the catalyst solution. In claim 1,
An apparatus for removing suspended particulate matter in exhaust gas, wherein a filter is provided in the rear chamber of the trapping part in the particulate matter removing apparatus main body to filter the catalyst solution. In claim 1,
Suspended particulate filter in the exhaust gas, characterized in that a drainage means to the exhaust gas line. In claim 6 ,
Suspended particulate filter in the exhaust gas, characterized in that the catalyst solution separated in the drain means provided recovery line for recovering the said catalyst solution storage means. A method for removing suspended particulate matter in exhaust gas, comprising using the apparatus for removing suspended particulate matter in exhaust gas according to any one of claims 1 to 7 , wherein the bypass line is opened when the exhaust gas is ventilated. Using the apparatus for removing suspended particulate matter in exhaust gas according to any one of claims 1 to 7 , the pressure difference between the front chamber and the rear chamber partitioned by the capturing part in the particulate removal apparatus body is measured, When this happens, the method for removing suspended particulate matter in the exhaust gas is characterized in that a bypass line for temporarily venting the exhaust gas is opened. An exhaust gas treatment system for purifying exhaust gas,
Interposed flue gas, exhaust gas treatment system characterized by having a floating particulate filter in the exhaust gas of claims 1 to 7 decomposing floating particulates in the exhaust gas. In claim 10 ,
An exhaust gas treatment system comprising a denitration device for decomposing nitrogen oxides in exhaust gas on the upstream side or the downstream side of the apparatus for removing suspended particulate matter in exhaust gas.

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