KR20220075000A - Diesel particulate filter device comprising composite catalyst layer and method for forming composite catalyst layer of diesel particulate filter device - Google Patents

Abstract

The present invention relates to a diesel dust filter device including a composite catalyst layer and a method for forming a composite catalyst layer in the diesel dust filter device. In one embodiment, the diesel dust filter device includes: a plurality of inlet channels having one end opened to introduce exhaust gas discharged from the diesel power generation facility, the other end being plugged in, and extending in the longitudinal direction; a plurality of discharge channels formed adjacent to the inlet channel and having one end plugged and the other end open to discharge a process gas from which harmful components including particulate matter and nitrogen oxides are removed from the exhaust gas, and extending in a longitudinal direction; and a porous wall defining a boundary between the inlet channel and the outlet channel and extending in the longitudinal direction, the porous wall fluidly communicating with the inlet channel and the outlet channel, wherein a first catalyst layer is formed on the inner wall surface of the inlet channel A second catalyst layer and a first catalyst layer are formed on the surface of the inner wall of the discharge channel, and the coating amount of the first catalyst layer increases from one end of the inner wall of the discharge channel to the other end, and the second catalyst layer The amount of silver coating is reduced.

Description

DIESEL PARTICULATE FILTER DEVICE COMPRISING COMPOSITE CATALYST LAYER AND METHOD FOR FORMING COMPOSITE CATALYST LAYER OF DIESEL PARTICULATE FILTER DEVICE

The present invention relates to a diesel dust filter device including a composite catalyst layer and a method for forming a composite catalyst layer in the diesel dust filter device.

Exhaust gas discharged from a diesel generator, etc. includes hydrocarbons, nitrogen oxides (NOX) and particulate matter (PM). Since these exhaust gases are harmful to the human body and the environment, regulations on emission of exhaust gases are being strengthened around the world, and research to satisfy regulatory requirements is being actively conducted.

1 shows a conventional exhaust gas purification apparatus. 1, the exhaust gas purification device 10 is a diesel oxidation catalyst (Diesel Oxidation Catalyst, DOC) unit (1), a heat source (4), a diesel particulate filter (Diesel Particulate Filter, DPF) unit (2) and Selective Catalytic Reduction (SCR) units 3 are sequentially provided.

Referring to FIG. 1, the exhaust gas of the diesel generator flows into the front end of the diesel oxidation catalyst unit 1 to oxidize nitrogen oxide (NO) in the exhaust gas to nitrogen dioxide (NO ₂ ), and SOF (Soluble Organic) Fraction) to increase the removal efficiency of soot and nitrogen oxides of the diesel dust filter unit 2 and the selective reduction catalyst unit 3 disposed at the rear end. The diesel dust filter unit 2 collects soot in the exhaust gas through a method such as a honeycomb wall-flow filter, and uses a heat source 4 such as a burner or heater to collect the soot accumulated in the filter. Active regeneration of particulate matter. The selective reduction catalyst unit 3 uses ammonia or urea as a reducing agent to remove nitrogen oxides through a reduction reaction as shown in Equations 1 and 2:

[Equation 1]

4NO + 4NH ₃ + O ₂ → 4N ₂ + 6H ₂ O

[Equation 2]

2NO ₂ + 4NH ₃ + O ₂ → 3N ₂ + 6H ₂ O.

A conventional DPF unit is composed of a porous partition wall having a plurality of exhaust gas passages. The porous partition wall is formed as an open cell in which the inlet side and the outlet side are plugged at the ends in a zigzag manner.

The conventional DPF unit can be largely divided into a coating method in which an oxidation catalyst coating layer is formed on the partition wall, and a non-coating method in which a coating layer is not formed on the partition wall. In the uncoated method, the DPF unit was regenerated using a burner, and in the coated method, nitrogen oxide (NO) was oxidized to nitrogen dioxide (NO ₂ ) and the DPF unit was regenerated through a natural regeneration method.

In the conventional DPF, both wall surfaces of the zigzag cell are coated with the same catalyst, so that the entire reaction takes place only in the inlet cell of the DPF unit, and then exits in a wall-flow method, so the reaction in the outlet cell is mostly meaningless progressed and was ineffective. In addition, the SCR unit serves to decompose nitrogen oxide into nitrogen (N ₂ ) and water (H ₂ O) by a reduction method. In difficult places, exhaust gas was incompletely treated by installing only one type of unit or using a separate after-treatment device.

On the other hand, depending on the use of ammonia or urea reducing agent injected for reaction in the SCR unit, unreacted ammonia is discharged from the rear end of the DPF, which may cause environmental hazards. In addition, a separate ammonia oxidation catalyst facility is required to solve the problem of discharging unreacted ammonia, and thus there is a problem in that operation and maintenance costs are increased.

Background art related to the present invention is disclosed in Japanese Patent Laid-Open No. 2007-092627 (published on April 12, 2007, title of the invention: exhaust gas purification apparatus).

One object of the present invention is to provide a diesel dust filter device having excellent treatment efficiency of pollutants contained in diesel exhaust gas through oxidation and reduction reactions.

Another object of the present invention is to provide a diesel dust filter device that is excellent in economic feasibility by minimizing the amount of oxidation catalyst and reduction catalyst used, and capable of minimizing unreacted reaction of a reducing agent input for reduction reaction.

Another object of the present invention is to provide a diesel dust filter device capable of reducing the size and compactness of the exhaust gas purification device by eliminating the SCR device.

Another object of the present invention is to provide a method for forming a composite catalyst layer of the diesel dust filter device.

Another object of the present invention is to provide an exhaust gas purification device including the diesel dust filter device.

One aspect of the present invention relates to a diesel dust filter device including a composite catalyst layer. In one embodiment, the diesel dust filter device including the composite catalyst layer includes: a plurality of inlet channels having one end open, exhaust gas discharged from the diesel power generation facility, and plugging the other end, extending in the longitudinal direction; a plurality of discharge channels formed adjacent to the inlet channel and having one end plugged and the other end open to discharge a process gas from which harmful components including particulate matter and nitrogen oxides are removed from the exhaust gas, and extending in a longitudinal direction; and a porous wall defining a boundary between the inlet channel and the outlet channel and extending in the longitudinal direction, the porous wall fluidly communicating with the inlet channel and the outlet channel, wherein a first catalyst layer is formed on the inner wall surface of the inlet channel and a second catalyst layer on a surface of the inner wall of the discharge channel and a composite catalyst layer having a first catalyst layer formed on the surface of the second catalyst layer, and the first catalyst layer of the composite catalyst layer has a coating amount from one end of the inner wall of the discharge channel to the other end. increases, and the coating amount of the second catalyst layer decreases.

In one embodiment, one or more of a thickness, a specific surface area, and a density of the first catalyst layer may increase or decrease from one end to the other end of the inner wall of the inflow channel.

In one embodiment, one or more of a thickness, a specific surface area, and a density of the first catalyst layer of the composite catalyst layer increases from one end of the inner wall of the discharge channel to the other end, and the second catalyst layer has at least one of a thickness, a specific surface area, and a density. can decrease.

In one embodiment, the first catalyst layer includes a first active ingredient supported on a support, and the first active ingredient includes at least one of platinum (Pt), palladium (Pd), rhodium (Rh) and cerium (Ce). And, the support may include at least one of aluminum oxide (Al ₂ O ₃ ) and zeolite.

In one embodiment, the second catalyst includes a second active ingredient and a cocatalyst supported on a support, and the second active ingredient is one of vanadium (V), copper (Cu), iron (Fe) and titanium (Ti). It includes at least one, the cocatalyst includes at least one of magnesium (Mg) and tungsten (W), and the support includes at least one of titanium dioxide (TiO ₂ ), zeolite, and zirconia.

In one embodiment, the specific surface areas of the first catalyst and the second catalyst may each be greater than 70 m ² /g.

In one embodiment, the porous wall may include one or more of silicon carbide, aluminum titanate, and cordierite.

Another aspect of the present invention relates to a method for forming a composite catalyst layer of the diesel dust filter device. In one embodiment, the method for forming the composite catalyst layer of the diesel dust filter device includes: forming a second catalyst layer by applying and curing a second catalyst coating agent on the inner wall surface of the exhaust channel of the diesel dust filter device; and applying and curing a first catalyst coating agent on the surface of the second catalyst layer to form a first catalyst layer to form a composite catalyst layer; the first catalyst layer of the composite catalyst layer from one end to the other end of the inner wall of the discharge channel The amount of silver coating increases, and the coating amount of the second catalyst layer decreases.

In one embodiment, one or more of a thickness, a specific surface area, and a density of the first catalyst layer may increase or decrease from one end to the other end of the inner wall of the inflow channel.

In one embodiment, one or more of a thickness, a specific surface area, and a density of the first catalyst layer of the composite catalyst layer increases from one end of the inner wall of the discharge channel to the other end, and the second catalyst layer has at least one of a thickness, a specific surface area, and a density. can decrease.

In one embodiment, the first catalyst coating agent includes a first active ingredient, a support and a solvent, and the first active ingredient is at least one of platinum (Pt), palladium (Pd), rhodium (Rh) and cerium (Ce). Including, the support may include at least one of aluminum oxide (Al ₂ O ₃ ) and zeolite.

In one embodiment, the second catalyst coating agent includes a second active ingredient, a promoter, a support and a solvent, and the second active ingredient is vanadium (V), copper (Cu), iron (Fe) and titanium (Ti). one or more of, the promoter includes one or more of magnesium (Mg) and tungsten (W), and the support includes one or more of titanium dioxide (TiO ₂ ), zeolite, and zirconia.

In one embodiment, the first catalyst coating agent and the second catalyst coating agent may be cured at 300 to 600°C, respectively.

Another aspect of the present invention relates to an exhaust gas purification device including the diesel dust filter device.

When the diesel dust filter device according to the present invention is applied, the treatment efficiency of pollutants contained in diesel exhaust gas through oxidation and reduction reactions is excellent, and the use of oxidation catalysts and reduction catalysts is minimized to provide excellent economic efficiency and reduction reaction. For this purpose, it is possible to minimize the non-reaction of the reducing agent input, and it is possible to exclude the SCR device, so that it is possible to make the exhaust gas purification device compact and small-sized.

1 shows a conventional exhaust gas purification apparatus.
2 is a view showing a diesel dust filter device according to an embodiment of the present invention.
3 is a cross-sectional view showing a diesel dust filter device according to an embodiment of the present invention.
4 shows an exhaust gas purification apparatus according to an embodiment of the present invention.

In describing the present invention, if it is determined that a detailed description of a related known technology or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

And, the terms described below are terms defined in consideration of functions in the present invention, which may vary depending on the intention or custom of a user or operator, and thus definitions should be made based on the content throughout this specification describing the present invention.

Diesel dust filter device including a composite catalyst layer

One aspect of the present invention relates to a diesel dust filter device including a composite catalyst layer. Specifically, the present invention relates to a diesel generator exhaust gas post-treatment device, and conventional diesel generator exhaust gas for treating hydrocarbons (HC), soot (Soot, unburned carbon and particulate matter (PM), etc.) and nitrogen oxides (NOx) It relates to an improved method of a diesel dust filter device (hereafter DPF) in an exhaust gas purification system for

In addition, in order to solve the problems of the prior art, different combinations of oxidation catalyst and reduction catalyst are coated on both cells of the DPF device, and the oxidation catalyst is coated in a double layer on the top of the reduction catalyst on the outlet side, using an SCR device A DPF device that simultaneously proceeds the oxidation-reduction-oxidation reaction was completed.

FIG. 2 shows a diesel dust filter device (DPF device) according to an embodiment of the present invention, and FIG. 3 shows a cross-section of a diesel dust filter device according to an embodiment of the present invention.

2 and 3, the diesel dust filter device 1000 including a composite catalyst layer has one end opened, exhaust gas (A) discharged from the diesel power generation facility is introduced, and the other end is plugged, extending in the longitudinal direction. a plurality of inlet channels 100 being; a plurality of discharge channels 200 formed adjacent to the inlet channel 100, one end of which is plugged and the other end of which is opened to discharge the process gas (B), extending in the longitudinal direction; and a porous wall 300 that defines a boundary between the inlet channel 100 and the outlet channel 200 and extends in the longitudinal direction, and fluidly communicates the inlet channel and the outlet channel.

Referring to FIG. 2 , the inlet channel 100 and the outlet channel 200 may be alternately arranged. When arranged as described above, it is possible to easily remove the particle component of the exhaust gas of the diesel generator.

Referring to FIG. 3 , the first catalyst layer 110 is formed on the inner wall surface of the inlet channel 100 , the second catalyst layer 120 is formed on the inner wall surface of the outlet channel 200 , and the first catalyst layer is formed on the surface of the second catalyst layer. It includes a composite catalyst layer 210 on which the catalyst layer 110 is formed. When the composite catalyst layer is formed as described above, it is possible to treat the exhaust gas through the reduction of nitrogen oxides inside the DPF device, and it is possible to minimize the maintenance cost by eliminating the SCR device.

Referring to FIG. 3 , the composite catalyst layer 210 is formed as a double layer, and the coating amount of the first catalyst layer 110 of the composite catalyst layer 210 increases from one end of the inner wall of the discharge channel 200 to the other end, and the second The catalyst layer 120 has a reduced coating amount. When the first catalyst layer and the second catalyst layer are formed as described above, the oxidation and reduction reactivity of the exhaust gas in the exhaust channel is excellent, and the use of expensive catalysts can be minimized, thereby improving economic efficiency. For example, from one end to the other end of the inner wall of the discharge channel, the thickness of the first catalyst layer linearly increases from 0 to 100% of the total thickness of the composite catalyst layer, and the thickness of the second catalyst layer linearly increases from 100 to 0%. can decrease.

For example, the coating amount of the first catalyst layer 110 of the composite catalyst layer 210 increases linearly from one end of the inner wall of the discharge channel 200 to the other end, and the coating amount of the second catalyst layer 120 linearly decreases. can do. When forming the composite catalyst layer as described above, the exhaust gas treatment efficiency is more excellent than using a separate SCR device, while the amount of catalyst used can be minimized.

In one embodiment, one or more of a thickness, a specific surface area, and a density of the first catalyst layer 110 may increase or decrease from one end to the other end of the inner wall of the inflow channel 100 . Under the above conditions, the oxidation reaction efficiency of the exhaust gas and the cost reduction effect may be excellent.

In one embodiment, one or more of the thickness, specific surface area and density of the first catalyst layer 110 of the composite catalyst layer 200 increases from one end to the other end of the inner wall of the discharge channel, and the second catalyst layer 120 has a thickness, One or more of specific surface area and density may decrease. Under the above conditions, the efficiency of the oxidation reaction and reduction reaction of the exhaust gas and the cost reduction effect may be excellent.

In one embodiment, each of the inlet channel and the outlet channel may have a circular, elliptical or polygonal longitudinal cross-section. For example, it may be a rectangle.

Referring to FIG. 3 , the exhaust gas moves through the first catalyst layer, the composite catalyst layer, and the porous wall, and oxidation and reduction reactions proceed so that particulate matter and nitrogen oxides can be easily removed.

In one embodiment, the porous wall 300 may include one or more of silicon carbide, aluminum titanate, and cordierite (2MgO·2Al ₂ O ₃ ·5SiO ₂ ).

In one embodiment, the porous wall may have pores having a size of 5 μm to 80 μm. In the present specification, the “size” of the pores is defined as meaning the diameter or the maximum length of the pores. In the pore size condition, while preventing equipment load of the DPF device, particulate matter contained in the exhaust gas does not pass through the porous wall, so that the exhaust gas treatment efficiency may be excellent.

In one embodiment, the porous wall may have a porosity of 20 to 90%. Exhaust gas treatment efficiency may be excellent under the above conditions.

In one embodiment, the first catalyst layer may include a first catalyst, and the first catalyst may include a first active ingredient supported on a support. The first catalyst layer may oxidize pollutant components such as hydrocarbons, particulate matter, nitrogen monoxide and carbon monoxide included in the exhaust gas.

For example, the first catalyst layer may include 5 to 70% by weight of the first active ingredient and 30 to 95% by weight of the support. When included in the above weight ratio, the oxidation reaction efficiency with the high-temperature exhaust gas may be excellent, and the cost-effectiveness, durability and thermal stability of the first catalyst may be excellent.

In one embodiment, the first active ingredient may include one or more of platinum (Pt), palladium (Pd), rhodium (Rh), and cerium (Ce). The first active ingredient may be included in an amount of 5 to 70% by weight based on the total weight of the first catalyst layer. When included in the above content, the oxidation reaction efficiency with the high-temperature exhaust gas may be excellent, and the cost-effectiveness, durability and thermal stability of the first catalyst layer may be excellent. For example, 5 to 30% by weight may be included.

In one embodiment, the support may include at least one of aluminum oxide (Al ₂ O ₃ ) and zeolite. When the above type of support is included, durability and thermal stability of the first catalyst layer may be excellent.

In one embodiment, the support may be included in an amount of 30 to 95% by weight based on the total weight of the first catalyst layer. When included in the above range, durability and thermal stability of the first catalyst layer may be excellent. For another example, 70 to 95% by weight may be included.

In one embodiment, the first catalyst may have a specific surface area greater than 70 m ² /g. In the above condition, while preventing the equipment load of the DPF device, the reaction efficiency with the exhaust gas may be excellent. For example, the first catalyst may have a specific surface area of 75 to 300 m ² /g.

In one embodiment, the second catalyst layer of the composite catalyst layer may be reduced by reacting with pollutants including nitrogen oxides in the exhaust gas.

In one embodiment, a reducing agent input unit (not shown) through which the reducing agent is introduced into the DPF device is further provided, so that the reducing agent can be introduced into the second catalyst layer. When the reducing agent is introduced into the DPF device, nitrogen oxides in the exhaust gas may be reacted with the reducing agent to reduce and remove nitrogen and water vapor. In one embodiment, the reducing agent may include at least one of ammonia (NH ₃ ) and urea.

In the present invention, the composite catalyst layer includes the first catalyst layer, and by oxidizing nitrogen monoxide in the exhaust gas to nitrogen dioxide, the reduction reaction efficiency of the second catalyst layer can be further improved.

In one embodiment, the second catalyst may include a second active ingredient and a co-catalyst supported on a support.

In one embodiment, the second active ingredient may include one or more of vanadium (V), copper (Cu), iron (Fe), and titanium (Ti). When the component is included, reactivity with nitrogen oxides in the exhaust gas may be excellent.

In one embodiment, the second active ingredient may be included in an amount of 10 to 60% by weight based on the total weight of the second catalyst layer. When included in the above range, the durability of the second catalyst layer may be excellent, and reactivity with nitrogen oxides in the exhaust gas may be excellent.

In one embodiment, the co-catalyst may include at least one of magnesium (Mg) and tungsten (W). When the type of cocatalyst is included, durability of the second catalyst and reaction efficiency of the second active ingredient may be excellent.

In one embodiment, the cocatalyst may be included in an amount of 1 to 15% by weight based on the total weight of the second catalyst layer. When included in the above range, durability of the second catalyst layer and reaction efficiency of the second active ingredient may be excellent.

In one embodiment, the support may include one or more of titanium dioxide (TiO ₂ ), zeolite, and zirconia (ZrO ₂ ). When the above type of support is included, durability and thermal stability of the second catalyst may be excellent.

In one embodiment, the support may be included in an amount of 30 to 80% by weight based on the total weight of the second catalyst layer. When included in the above range, durability and thermal stability of the second catalyst layer may be excellent.

In one embodiment, the second catalyst may have a specific surface area greater than 70 m ² /g. In the above condition, while preventing the equipment load of the DPF device, the reaction efficiency with the exhaust gas may be excellent. For example, the second catalyst may have a specific surface area of 75 to 300 m ² /g.

A method for forming a complex catalyst layer in a diesel dust filter device

Another aspect of the present invention relates to a method for forming a composite catalyst layer of the diesel dust filter device. In one embodiment, the method for forming the composite catalyst layer of the diesel dust filter device includes: forming a second catalyst layer by applying and curing a second catalyst coating agent on the inner wall surface of the exhaust channel of the diesel dust filter device; and applying and curing a first catalyst coating agent on the surface of the second catalyst layer to form a first catalyst layer to form a composite catalyst layer; the first catalyst layer of the composite catalyst layer from one end to the other end of the inner wall of the discharge channel The amount of silver coating increases, and the coating amount of the second catalyst layer decreases.

For example, the first catalyst layer and the composite catalyst layer may be formed by drying and curing after wash coating.

When the composite catalyst layer is formed by forming the first catalyst layer and the second catalyst layer as described above, the oxidation and reduction reactivity of the exhaust gas in the exhaust channel is excellent, and the use of expensive catalysts can be minimized, so that the economy can be excellent. For example, the coating amount of the first catalyst layer 110 of the composite catalyst layer 210 increases linearly from one end of the inner wall of the discharge channel 200 to the other end, and the coating amount of the second catalyst layer 120 linearly decreases. can do.

In one embodiment, one or more of a thickness, a specific surface area, and a density of the first catalyst layer may increase or decrease from one end to the other end of the inner wall of the inflow channel.

In one embodiment, one or more of a thickness, a specific surface area, and a density of the first catalyst layer of the composite catalyst layer increases from one end of the inner wall of the discharge channel to the other end, and the second catalyst layer has at least one of a thickness, a specific surface area, and a density. can decrease. In addition, the thickness of the composite catalyst layer may be constant.

In one embodiment, the first catalyst coating agent may include a first active ingredient, a support and a solvent.

In one embodiment, the first active ingredient may include one or more of platinum (Pt), palladium (Pd), rhodium (Rh), and cerium (Ce).

In one embodiment, the support may include at least one of aluminum oxide (Al ₂ O ₃ ) and zeolite.

In one embodiment, the solvent may include at least one of water and alcohol. For example, the alcohol may include one or more of ethanol, methanol, butanol, isobutanol, and isopropyl alcohol. When the solvent is included, dispersibility and miscibility of the first catalyst coating agent may be excellent.

In one embodiment, the solvent may be included in an amount of 50 to 300 parts by weight based on 100 parts by weight of the total of the first active ingredient and the support. When included in the above content, dispersibility and miscibility of the first catalyst coating agent may be excellent.

In one embodiment, the second catalyst coating agent may include a second active ingredient, a co-catalyst, a support, and a solvent.

The second active ingredient may include at least one of vanadium (V), copper (Cu), iron (Fe), and titanium (Ti).

The promoter may include at least one of magnesium (Mg) and tungsten (W).

The support may include at least one of titanium dioxide (TiO ₂ ), zeolite, and zirconia.

In one embodiment, the solvent may include at least one of water and alcohol. For example, the alcohol may include one or more of ethanol, methanol, butanol, isobutanol, and isopropyl alcohol. When the solvent is included, dispersibility and miscibility of the second catalyst coating agent may be excellent.

In one embodiment, the solvent may be included in an amount of 50 to 300 parts by weight based on 100 parts by weight of the total of the second active ingredient, the cocatalyst and the support. When included in the above content, dispersibility and miscibility of the second catalyst coating agent may be excellent.

In one embodiment, the first catalyst coating agent and the second catalyst coating agent may be cured at 300 to 600°C, respectively. Under the above conditions, the first catalyst layer and the second catalyst layer are easily formed, and durability may be excellent.

For example, a second catalyst coating agent is applied to the inner wall surface of the discharge channel, dried at 80 to 200° C., and cured at 300 to 600° C. to form a second catalyst layer, and then the first catalyst coating agent is applied 80 The first catalyst layer may be formed by drying at ~200°C and then curing at 300~600°C. Under the above conditions, the first catalyst layer and the second catalyst layer are easily formed, and durability and thermal stability may be excellent.

Exhaust gas purification device including diesel dust filter device

Another aspect of the present invention relates to an exhaust gas purification device including the diesel dust filter device. 4 shows an exhaust gas purification apparatus according to an embodiment of the present invention. 4, the exhaust gas purification device 2000 is a diesel oxidation catalyst (Diesel Oxidation Catalyst, DOC) for converting nitrogen oxide (NOX) contained in the exhaust gas introduced through the gas inlet to nitrogen dioxide (NO ₂ ) device 1100; and a diesel particle filter (DPF) device 1000 provided at the rear end of the DOC device, through which the exhaust gas discharged from the DOC unit is introduced to remove harmful components including particulate matter and nitrogen oxides.

In one embodiment, a heat source 1200 may be further provided between the DOC device and the DPF device. In one embodiment, the heat source may include a burner or a heater.

When the diesel dust filter device according to the present invention is applied, the treatment efficiency of pollutants contained in diesel exhaust gas through oxidation and reduction reactions is excellent, and the use of oxidation catalysts and reduction catalysts is minimized to provide excellent economic efficiency and reduction reaction. For this purpose, it is possible to minimize the non-reaction of the reducing agent input, and it is possible to exclude the SCR device, so that it is possible to make the exhaust gas purification device compact and small-sized.

Hereinafter, the configuration and operation of the present invention will be described in more detail through preferred embodiments of the present invention. However, this is presented as a preferred example of the present invention and cannot be construed as limiting the present invention in any sense. Content not described here will be omitted because it can be technically inferred sufficiently by a person skilled in the art.

Examples and Comparative Examples

Example 1

(1) Preparation of the first catalyst coating agent: 100 parts by weight of a mixture containing 5 to 30% by weight of the first active ingredient (platinum (Pt) and 70 to 95% by weight of the support (aluminum oxide)) and 300 parts by weight of a solvent (alcohol) are mixed Thus, a first catalyst coating agent was prepared.

(2) Preparation of second catalyst coating agent: second active ingredient (vanadium (V) 10 to 35 wt%, cocatalyst (tungsten oxide (WO ₃ )) 1 to 10 wt% and support (aluminum oxide) 60 to 85 wt% A second catalyst coating agent was prepared by mixing 100 parts by weight of a mixture containing and 300 parts by weight of a solvent (alcohol).

(3) DPF device manufacturing: As shown in FIGS. 2 and 3, one end is opened to let the exhaust gas discharged from the diesel power generation facility flow in, and the other end is plugged in, and a plurality of inlet channels 100 extending in the longitudinal direction, the inflow A plurality of discharge channels that are formed adjacent to the channel 100, have one end plugged in and the other end open to discharge a process gas from which harmful components including particulate matter and nitrogen oxides are removed from the exhaust gas, and extend in the longitudinal direction. A porous wall 300 was formed to define a boundary between 200 and the inlet channel 100 and the outlet channel 200 and extend in the longitudinal direction, and fluidly communicate the inlet and outlet channels. The porous wall was manufactured by extrusion molding silicon carbide by a known method.

Then, the first catalyst coating agent is applied to the inner wall surface of the inlet channel 100 (wash coat), dried at 100 to 200° C., and cured at 200 to 600° C. to form a first catalyst layer (specific surface area of 70 m ² /g) was formed. In addition, the second catalyst coating agent is applied (wash coat) to the inner wall surface of the discharge channel 200, dried at 100 to 200° C., and cured at 200 to 600° C. to form a second catalyst layer (specific surface area 130 m ² /g) did Then, the first catalyst coating agent is applied (wash coat) to the surface of the second catalyst coating agent, dried at 100 to 200 ° C., and cured at 200 to 600 ° C. to obtain a first catalyst layer (specific surface area 130 m ² /g). formed. At this time, the thickness of the first catalyst layer of the composite catalyst layer increases linearly from one end to the other end of the discharge channel 200, and the thickness of the second catalyst layer is formed to decrease linearly, so that the diesel dust filter (DPF) device (1000) was prepared.

Example 2

A DPF device was manufactured in the same manner as in Example 1, except that the first catalyst layer and the second catalyst layer of the composite catalyst layer were respectively formed with a specific surface area of 250 m ² /g. The specific surface areas of the first catalyst layer and the second catalyst layer were measured using a specific surface area measuring device (Micromeritics, product name: ASAP-2020).

Comparative Example 1

A DPF device was manufactured in the same manner as in Example 1, except that only the second catalyst layer was formed on the surface of the inner wall of the discharge channel of the DPF device.

Comparative Example 2

A composite catalyst layer is formed by sequentially forming a second catalyst layer and a first catalyst layer on the surface of the inner wall of the discharge channel, except that the second catalyst layer and the first catalyst layer are formed to have a uniform thickness along the length direction of the discharge channel, A DPF device was manufactured in the same manner as in Example 1.

Comparative Example 3

A DPF device was manufactured in the same manner as in Example 1, except that only the second catalyst layer was formed on the surface of the inner wall of the discharge channel.

test example

Exhaust gas purification devices were manufactured by connecting a diesel oxidation catalyst (DOC) device commonly used in the front end of the DPF devices of Examples and Comparative Examples 1 to 3, respectively. The exhaust gas purification devices of the above examples and comparative examples are respectively connected to the rear end of the diesel generator, exhaust gas having a temperature of 350° C. generated during diesel power generation is introduced into the DPF device through the DOC device, and a reducing agent (ammonia) is applied to the DPF device. The exhaust gas was treated by a known method, and the differential pressure (mbar) change between the front end and the rear end during operation of the DPF device, the nitrogen oxide removal rate, and the reducing agent unreacted rate were measured.

(1) nitrogen oxide removal rate (%): the initial concentration (ppm) of nitrogen oxide in the exhaust gas flowing into the DPF device and the nitrogen oxide concentration (ppm) of the processing gas discharged through the discharge channel of the DPF are measured, , the nitrogen oxide removal rate (%) was calculated and shown in Table 1 below.

(2) Reductant unreacted rate (%): The initial concentration (ppm) of the reducing agent (ammonia) flowing into the DPF device and the reducing agent concentration (ppm) of the processing gas discharged through the discharge channel of the DPF are measured, and ammonia The unreacted rate (%) was calculated and shown in Table 1 below.

In Table 1, the amount of catalyst in the exhaust channel is relative to the amount of use in Examples 2 and 3 and Comparative Examples 1 to 3 based on the content of the composite catalyst layer formed on the inner wall of the exhaust channel in Example 1.

Referring to the results in Table 1, it can be seen that Examples 1 and 2 of the present invention have superior nitrogen oxide removal efficiency in exhaust gas and minimize the unreacted rate of the reducing agent, compared to Comparative Examples 1 and 3.

On the other hand, in the case of Comparative Example 1 in which the first catalyst layer was not formed inside the discharge channel, the reaction efficiency of the reducing agent was reduced even though the amount of the second catalyst layer was increased compared to Examples 1 and 2, and the first catalyst layer was formed inside the discharge channel. In the case of Comparative Example 2, in which the and second catalyst layers were applied to a uniform thickness, the nitrogen oxide removal rate and reducing agent reaction efficiency decreased even though the amount of the first catalyst layer and the second catalyst layer was increased compared to Examples 1 and 2, and the first catalyst layer was not formed. In the case of Comparative Example 3, which was not, it was found that the nitrogen oxide removal effect was lowered compared to Examples 1-2.

Up to now, the present invention has been looked at focusing on examples. Those of ordinary skill in the art to which the present invention pertains will understand that the present invention can be implemented in modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments are to be considered in an illustrative rather than a restrictive sense. The scope of the present invention is indicated in the claims rather than the foregoing description, and all differences within the scope equivalent thereto should be construed as being included in the present invention.

1: DOC unit 2: DPF unit
3: SCR unit 4: heat source
10: exhaust gas purification device 100: inlet channel
110: first coating layer 120: second coating layer
200: discharge channel 210: composite coating layer
300: porous wall 1000: DPF device
1100: DOC device 1200: heat source
2000: exhaust gas purification device

Claims (14)

a plurality of inlet channels having one end open and exhaust gas discharged from the diesel power generation facility introduced therein, the other end being plugged in, and extending in the longitudinal direction;
a plurality of discharge channels formed adjacent to the inlet channel and having one end plugged and the other end open to discharge a process gas from which harmful components including particulate matter and nitrogen oxides are removed from the exhaust gas, and extending in a longitudinal direction; and
a porous wall defining a boundary between the inlet channel and the outlet channel and extending in the longitudinal direction, the porous wall fluidly communicating the inlet channel and the outlet channel;
A first catalyst layer is formed on the inner wall surface of the inlet channel,
a second catalyst layer on a surface of the inner wall of the discharge channel and a composite catalyst layer in which a first catalyst layer is formed on the surface of the second catalyst layer;
The diesel dust filter device, characterized in that the coating amount of the first catalyst layer of the composite catalyst layer increases from one end to the other end of the inner wall of the discharge channel, and the coating amount of the second catalyst layer decreases.
The diesel dust filter device according to claim 1, wherein at least one of a thickness, a specific surface area and a density of the first catalyst layer increases or decreases from one end of the inner wall of the inlet channel to the other end.
The method according to claim 1, wherein at least one of a thickness, a specific surface area, and a density of the first catalyst layer of the composite catalyst layer increases from one end of the inner wall of the discharge channel to the other end, and the second catalyst layer has one of a thickness, a specific surface area, and a density. Diesel dust filter device, characterized in that the abnormality is reduced.
According to claim 1, wherein the first catalyst layer comprises a first active ingredient supported on a support,
The first active ingredient includes at least one of platinum (Pt), palladium (Pd), rhodium (Rh) and cerium (Ce),
The support is a diesel dust filter device, characterized in that it comprises at least one of aluminum oxide (Al ₂ O ₃ ) and zeolite (zeolite).
According to claim 1, wherein the second catalyst comprises a second active ingredient and a cocatalyst supported on a support,
The second active ingredient includes at least one of vanadium (V), copper (Cu), iron (Fe) and titanium (Ti),
The promoter includes at least one of magnesium (Mg) and tungsten (W),
The support is titanium dioxide (TiO ₂ ) Diesel dust filter device, characterized in that it comprises at least one of zeolite (zeolite) and zirconia.
The diesel dust filter device according to claim 1, wherein the specific surface areas of the first catalyst and the second catalyst each exceed 70 m ² /g.
The diesel dust filter device according to claim 1, wherein the porous wall comprises at least one of silicon carbide, aluminum titanate and codierite.
A plurality of inlet channels extending in the longitudinal direction are formed adjacent to the inlet channel, one end being opened to introduce exhaust gas discharged from the diesel power generation facility, and the other end being plugged in, one end being plugged in and the other end being opened to open the exhaust gas A process gas from which harmful components including particulate matter and nitrogen oxides have been removed is discharged, a plurality of discharge channels extending in the longitudinal direction and a boundary between the inlet and outlet channels are defined and extended in the longitudinal direction, the inlet A method for forming a composite catalyst layer in a diesel dust filter device comprising a porous wall fluidly communicating a channel and an outlet channel, wherein a first catalyst layer is formed on a surface of the inner wall of the inlet channel,
forming a second catalyst layer by applying and curing a second catalyst coating agent on the inner wall surface of the discharge channel; and
Forming a composite catalyst layer by applying and curing a first catalyst coating agent on the surface of the second catalyst layer to form a first catalyst layer;
The method for forming a composite catalyst layer for a diesel dust filter device, characterized in that the coating amount of the first catalyst layer of the composite catalyst layer increases from one end to the other end of the inner wall of the exhaust channel, and the coating amount of the second catalyst layer decreases.
The method according to claim 8, wherein at least one of a thickness, a specific surface area, and a density of the first catalyst layer increases or decreases from one end of the inner wall of the inlet channel to the other end.
The method according to claim 8, wherein one or more of a thickness, a specific surface area, and a density of the first catalyst layer of the composite catalyst layer increases from one end of the inner wall of the discharge channel to the other end, and the second catalyst layer has one of a thickness, a specific surface area, and a density. A method for forming a composite catalyst layer of a diesel dust filter device, characterized in that the abnormality is reduced.
The method of claim 8, wherein the first catalyst coating agent comprises a first active ingredient, a support and a solvent,
The first active ingredient includes at least one of platinum (Pt), palladium (Pd), rhodium (Rh) and cerium (Ce),
The support is aluminum oxide (Al ₂ O ₃ ) and zeolite (zeolite), characterized in that it comprises at least one of the composite catalyst layer forming method of a diesel dust filter device.
The method of claim 8, wherein the second catalyst coating agent comprises a second active ingredient, a co-catalyst, a support and a solvent,
The second active ingredient includes at least one of vanadium (V), copper (Cu), iron (Fe) and titanium (Ti),
The promoter includes at least one of magnesium (Mg) and tungsten (W),
The support is titanium dioxide (TiO ₂ ), zeolite (zeolite), and a method for forming a composite catalyst layer of a diesel dust filter device, characterized in that it comprises at least one of zirconia.
The method of claim 8, wherein the first catalyst coating agent and the second catalyst coating agent are each cured at 300 to 600°C.
An exhaust gas purification device comprising the diesel dust filter device of any one of claims 1 to 7.

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