KR102183057B1 - Exhaust gas treatment apparatus - Google Patents

Abstract

An exhaust gas treatment apparatus is disclosed.
An exhaust gas treatment apparatus according to an embodiment of the present invention includes a reactor through which exhaust gas is introduced; And an adsorption catalyst member provided inside the reactor. Including, the adsorption catalyst member may be attached to the adsorption catalyst for adsorbing sulfur oxides contained in the exhaust gas and sequentially removing nitrogen oxides contained in the exhaust gas.

Description

Exhaust gas treatment system {EXHAUST GAS TREATMENT APPARATUS}

The present invention relates to an exhaust gas treatment apparatus that treats exhaust gas.

The exhaust gas treatment device is a device that treats exhaust gas discharged from an exhaust gas discharge device such as an engine and then discharges it to the outside.

Such an exhaust gas treatment device includes a scrubber that removes sulfur oxides from exhaust gas, and a selective catalytic reduction device called SCR (Selective Catalyst Reduction) that removes nitrogen oxides from exhaust gas.

Conventionally, in order to remove both sulfur oxides and nitrogen oxides from exhaust gas, both the above-described scrubber and the selective catalytic reduction device had to be provided. In addition, in some cases, even when removing sulfur oxides or nitrogen oxides from exhaust gas, both the above-described scrubber and selective catalytic reduction device must be provided.

Therefore, in places where there is not much free space such as a ship, it is not easy to install both a scrubber and a selective catalytic reduction device, so that sulfur oxides and nitrogen oxides are simultaneously removed from exhaust gas or, in some cases, sulfur oxides from exhaust gas. Or it was not easy to remove nitrogen oxides.

In addition, in the conventional scrubber, treated water such as seawater or fresh water is injected into the exhaust gas to remove sulfur oxides from the exhaust gas.In this case, since the amount of treated water used is large, treated water is supplied to the scrubber in addition to the scrubber. A configuration and a configuration for removing sulfur oxides from exhaust gas to treat treated water containing sulfur oxides had to be provided separately.

The present invention has been made by recognizing at least one of the demands or problems occurring in the prior art as described above.

An aspect of an object of the present invention is to simultaneously remove sulfur oxides and nitrogen oxides from exhaust gas with a single exhaust gas treatment device.

The exhaust gas treatment apparatus according to an embodiment for realizing at least one of the above problems may include the following features.

An exhaust gas treatment apparatus according to an embodiment of the present invention includes a reactor through which exhaust gas is introduced; And an adsorption catalyst member provided inside the reactor. Including, the adsorption catalyst member may be attached to the adsorption catalyst for adsorbing sulfur oxides contained in the exhaust gas and sequentially removing nitrogen oxides contained in the exhaust gas.

In this case, the adsorption catalyst includes an adsorbent, and sulfur oxides contained in the exhaust gas are adsorbed by the adsorbent through a chemical reaction to become a desulfurization by-product, thereby being removed from the exhaust gas.

In addition, nitrogen oxides contained in exhaust gas can be removed from exhaust gas by chemically reacting with the desulfurization by-product to become a denitration by-product.

In addition, the adsorbent may include at least one of iron oxide (Fe ₂ O ₃ ), copper oxide (CuO), and cerium oxide (CeO).

In addition, the adsorption catalyst may further include a catalyst that helps nitrogen oxides contained in exhaust gas to be reduced to nitrogen by a reducing agent and removed from the exhaust gas.

In addition, the adsorption catalyst is in the form of a powder in which the adsorbent and catalyst are mixed, and the adsorption catalyst may be attached to the adsorption catalyst member by extrusion molding or an adhesive material.

In addition, after the catalyst in powder form is first attached to the adsorption catalyst member by extrusion molding or an adhesive material, the adsorbent in powder form may be attached to the adsorption catalyst member by adhesive material or extrusion molding.

In addition, the catalyst may include at least one of vanadium (V), tungsten (W), and titanium oxide (TiO ₂ ).

In addition, a reducing agent supply unit for mixing the reducing agent or a reducing agent precursor used as the reducing agent with the exhaust gas before the exhaust gas is introduced into the reactor; It may further include.

In addition, the reducing agent supply unit includes a reducing agent storage tank in which the reducing agent or a reducing agent precursor is stored, and one side is connected to an exhaust pipe connected to the reactor through which exhaust gas flows, and the other side is connected to the reducing agent storage tank. I can.

In addition, a regeneration agent supply unit for supplying a regeneration agent for regenerating the adsorbent into the reactor; It may further include.

In addition, the regenerating agent chemically reacts with the nitrogen oxide, sulfur oxide, desulfurization by-product and denitrification by-product contained in the exhaust gas to form an adsorbent precursor, and the adsorbent precursor is pyrolyzed by heat of the exhaust gas to be regenerated as an adsorbent.

In addition, the rejuvenating agent may be an aqueous alkali solution.

In addition, the temperature of the exhaust gas inside the reactor may be 200° C. or more and less than 500° C. to enable thermal decomposition of the adsorbent precursor and reduction of nitrogen oxides to nitrogen by the reducing agent and the catalyst.

In addition, the regeneration agent supply unit is a regenerant storage tank in which a regenerant is stored, one side is connected to the regeneration agent storage tank, and the other side passes through one surface of the reactor and is provided inside the reactor, and a regeneration agent supply pipe is provided inside the reactor. It may include a regenerant spray nozzle provided in a portion of the regeneration agent supply pipe provided in the.

In addition, the adsorption catalyst member may have an exhaust gas passage hole through which exhaust gas passes.

In addition, the exhaust gas passage hole may be formed in the adsorption catalyst member parallel to the exhaust gas flow direction inside the reactor.

As described above, according to the exemplary embodiment of the present invention, sulfur oxides and nitrogen oxides can be simultaneously removed from exhaust gas with one exhaust gas treatment device.

1 is a perspective view of an embodiment of an exhaust gas treatment apparatus according to the present invention.
2 is a view showing that the exhaust gas is treated in an embodiment of the exhaust gas treatment apparatus according to the present invention.
3 is a view showing other embodiments of the exhaust gas treatment apparatus according to the present invention.
4 and 5 are views showing a case where the exhaust gas treatment apparatus according to the present invention is installed on a ship.
6 and 7 are graphs showing experimental results of the performance of the adsorption catalyst attached to the adsorption catalyst member included in the exhaust gas treatment apparatus according to the present invention.
FIG. 8 is a diagram showing a related chemical reaction equation in which nitrogen oxides and sulfur oxides are respectively removed from exhaust gas in the exhaust gas treatment apparatus and the exhaust gas treatment method according to the present invention.
9 is a view showing an example of a process in which nitrogen oxides and sulfur oxides are removed from exhaust gas in the exhaust gas treatment apparatus and the exhaust gas treatment method according to the present invention.
10 is a view showing a process in which the adsorbent of the adsorption catalyst attached to the adsorption catalyst member is regenerated by the adsorbent regenerant in the exhaust gas treatment apparatus and exhaust gas treatment method according to the present invention.

In order to help understand the features of the present invention as described above, an exhaust gas treatment apparatus and an exhaust gas treatment method according to an embodiment of the present invention will be described in more detail below.

The embodiments described below will be described on the basis of embodiments most suitable for understanding the technical features of the present invention, and the technical features of the present invention are not limited by the described embodiments, but will be described below. It is to illustrate that the present invention can be implemented as in the embodiments. Accordingly, the present invention can be variously modified within the technical scope of the present invention through the embodiments described below, and such modified embodiments will fall within the technical scope of the present invention. In addition, in the reference numerals in the accompanying drawings in order to aid in understanding of the embodiments described below, related elements among the elements that perform the same function in each embodiment are indicated by numbers on the same or extension lines.

Hereinafter, an exhaust gas treatment apparatus and an exhaust gas treatment method according to the present invention will be described with reference to FIGS. 1 to 10.

1 is a perspective view of an embodiment of an exhaust gas treatment apparatus according to the present invention, FIG. 2 is a view showing that exhaust gas is treated in an embodiment of the exhaust gas treatment apparatus according to the present invention, and FIG. 4 and 5 are diagrams illustrating a case where the exhaust gas treatment device according to the present invention is installed on a ship.

In addition, FIGS. 6 and 7 are graphs showing the results of testing the performance of the adsorption catalyst attached to the adsorption catalyst member included in the exhaust gas treatment apparatus according to the present invention.

In addition, FIG. 8 is a view showing a related chemical reaction equation in which nitrogen oxides and sulfur oxides are each removed from exhaust gas in an exhaust gas treatment apparatus and an exhaust gas treatment method according to the present invention, and FIG. 9 is an exhaust gas treatment apparatus according to the present invention. And is a view showing an example of a process of removing nitrogen oxides and sulfur oxides from exhaust gas in the exhaust gas treatment method, and FIG. 10 is an adsorption attached to the adsorption catalyst member in the exhaust gas treatment apparatus and the exhaust gas treatment method according to the present invention. It is a diagram showing a process in which the adsorbent of the catalyst is regenerated by the adsorbent regenerating agent.

Exhaust gas treatment device

The exhaust gas treatment apparatus 100 according to the present invention may include a reactor 200, an adsorption catalyst member 300, a reducing agent supply unit 400, and a regenerant supply unit 500.

Exhaust gas may be introduced into the reactor 200. To this end, the reactor 200 may be connected to an exhaust gas discharge device ED from which exhaust gas is discharged. For example, the reactor 200 may be connected to an exhaust gas discharge device (ED) such as a main engine (ME) or an engine for power generation (GE) provided on a ship as shown in FIGS. 4 and 5. However, the exhaust gas discharging device ED connected to the reactor 200 is not particularly limited, and any known material such as a boiler (not shown) may be used as long as the exhaust gas is discharged.

The reactor 200 may have a shape that is elongated in the height direction as shown in FIGS. 1 and 2 and 3 (b), or may have a shape that is elongated in the length direction or the width direction as shown in FIG. 3(a). . However, the shape of the reactor 200 is not particularly limited, and the exhaust gas that is connected to the exhaust gas discharge device ED and discharged from the exhaust gas discharge device ED flows in and the adsorption catalyst member 300 is Any shape is possible as long as it can be provided.

The reactor 200 may be provided with an exhaust gas inlet 210, an exhaust gas outlet 220, and a treatment by-product outlet 230 as shown in FIG. 1.

Exhaust gas may be introduced into the reactor 200 through the exhaust gas inlet 210. To this end, an exhaust pipe PE connected to an exhaust gas discharge device ED may be connected to the exhaust gas inlet 210. In addition, the exhaust gas discharged from an exhaust gas discharge device (ED) such as a main engine (ME) or an engine for power generation (GE) and flowing through the exhaust pipe (PE) is discharged through the exhaust gas inlet 210 as shown in FIG. Likewise, it is introduced into the reactor 200 and may flow inside the reactor 200. The exhaust gas inlet 210 may be provided under the reactor 200 as shown in FIG. 1. However, the portion of the reactor 200 provided with the exhaust gas inlet 210 is not particularly limited, and the exhaust pipe PE connected to the exhaust gas discharge device ED is connected to the exhaust gas discharged from the exhaust gas discharge device ED. Any part of the reactor 200 may be provided as long as the gas can be introduced into the reactor 200.

The exhaust gas processed in the reactor 200 may be discharged through the exhaust gas outlet 220. For example, the exhaust gas from which at least one of sulfur oxides and nitrogen oxides has been removed while flowing inside the reactor 200 may be discharged through the exhaust gas outlet 220. An exhaust gas discharge pipe PD may be connected to the exhaust gas discharge port 220 as shown in FIG. 2. Exhaust gas discharged from the exhaust gas discharge port 220 flows into the turbocharger TC provided in the exhaust gas discharge pipe PD as shown in FIG. 4 through the exhaust gas discharge pipe PD, or is shown in FIG. It can be discharged to the outside as shown. The exhaust gas outlet 220 may be provided above the reactor 200 as shown in FIG. 1. However, the portion of the reactor 200 provided with the exhaust gas outlet 220 is not particularly limited, and the exhaust gas from which at least one of sulfur oxide and nitrogen oxide is removed while flowing inside the reactor 200 may be discharged. If it is a part, it may be provided in any part of the reactor 200.

As the exhaust gas is processed in the reactor 200, for example, a treatment byproduct generated when at least one of sulfur oxides and nitrogen oxides is removed from the exhaust gas may be discharged through the treatment byproduct outlet 230. The treatment by-product outlet 230 may be provided below the reactor 200 as shown in FIG. 1. However, the part of the reactor 200 provided with the treatment by-product outlet 230 is not particularly limited, and if the part in which the treatment by-product generated while the exhaust gas is processed in the reactor 200 can be discharged, the reactor 200 It can be provided in any part. A drain pipe PL may be connected to the treatment by-product outlet 230 as shown in FIGS. 4 and 5. In addition, the drain pipe PL may be connected to the treatment by-product collection tank TB. Accordingly, the treated by-product discharged through the treatment by-product discharge port 230 may be stored in the treatment by-product collection tank TB through the drain pipe PL. The treatment by-products stored in the treatment by-product collection tank TB may be disposed of or processed by a separate device (not shown) to be recycled.

The adsorption catalyst member 300 may be provided inside the reactor 200. An exhaust gas passage hole (not shown) through which the exhaust gas passes may be formed in the adsorption catalyst member 300. A plurality of exhaust gas passage holes may be formed in the adsorption catalyst member 300. The number of exhaust gas passage holes formed in the adsorption catalyst member 300 is not particularly limited, and any number may be used, and one may be used.

The exhaust gas passage hole may be formed in the adsorption catalyst member 300 in parallel with the flow direction of the exhaust gas in the reactor 200. For example, an exhaust gas passage hole may be formed in the adsorption catalyst member 300 in the height direction or the thickness direction of the adsorption catalyst member 300. However, the shape of the exhaust gas passage hole formed in the adsorption catalyst member 300 is not particularly limited, and any shape may be used as long as it is a shape through which the exhaust gas can pass.

The adsorption catalyst member 300 may have a plate shape having a predetermined thickness, as shown in FIG. 1. However, the shape of the adsorption catalyst member 300 is not particularly limited, and any shape may be used as long as the above-described exhaust gas passage hole may be formed and may be provided in the reactor 200.

A plurality of adsorption catalyst members 300 may be provided in the reactor 200. In this case, the plurality of adsorption catalyst members 300 may be provided in the reactor 200 to be spaced apart from each other by a predetermined distance. For example, as shown in Figs. 1, 2, and 3 (a), a plurality of adsorption catalyst members 300 are spaced apart from each other in the longitudinal direction or the width direction of the reactor 200 in the interior of the reactor 200. It can be provided. In addition, as shown in (b) of FIG. 3, a plurality of adsorption catalyst members 300 may be provided in the reactor 200 to be spaced apart from each other by a predetermined distance in the height direction of the reactor 200. However, the configuration in which the plurality of adsorption catalyst members 300 are provided in the reactor 200 is not particularly limited, and any configuration is possible.

An adsorption catalyst (not shown) may be attached to the adsorption catalyst member 300. The adsorption catalyst may be attached to the adsorption catalyst member 300 by extrusion molding or an adhesive material, for example. However, the configuration in which the adsorption catalyst is attached to the adsorption catalyst member 300 is not particularly limited, and any known configuration may be used.

The adsorption catalyst may adsorb sulfur oxides contained in exhaust gas and may sequentially remove nitrogen oxides contained in exhaust gas. In addition, the adsorption catalyst may help nitrogen oxides contained in the exhaust gas to be reduced to nitrogen by the reducing agent and removed from the exhaust gas.

The adsorption catalyst may include an adsorbent and a catalyst. For example, the adsorption catalyst may be in the form of a powder in which an adsorbent and a catalyst are mixed. In addition, an adsorption catalyst in powder form may be attached to the adsorption catalyst member 300 by extrusion molding or an adhesive material. In addition, the powdery catalyst may be first attached to the adsorption catalyst member 300 by extrusion molding or an adhesive material, and then the powdery adsorbent may be attached to the adsorption catalyst member 300 by adhesive material or extrusion molding. However, the shape of the adsorption catalyst and the structure attached to the adsorption catalyst member 300 are not particularly limited, and any shape and structure may be used as long as it includes an adsorbent and a catalyst.

The adsorbent may allow sulfur oxides contained in exhaust gas to be adsorbed and nitrogen oxides to be sequentially removed. For example, sulfur oxides contained in exhaust gas can be removed from exhaust gas by being adsorbed to the adsorbent through a chemical reaction to become a desulfurization by-product. Further, the desulfurization by-product chemically reacts with the nitrogen oxide contained in the exhaust gas to become a denitration by-product, so that nitrogen oxides can be removed from the exhaust gas.

The adsorbent may include at least one of iron oxide (Fe ₂ O ₃ ), copper oxide (CuO), and cerium oxide (CeO). As described above, the sulfur oxides contained in the exhaust gas are adsorbed to become desulfurization by-products, and the desulfurization by-products react with nitrogen oxides contained in the exhaust gas to become denitrification by-products, thereby removing sulfur oxides and nitrogen oxides from the exhaust gas. In addition to the role of making it possible, it can also serve as a cocatalyst to increase the activity of the catalyst contained in the adsorption catalyst.

When the adsorbent is, for example, iron oxide (Fe ₂ O ₃ ), sulfur oxides contained in the exhaust gas can be removed from the exhaust gas by being adsorbed on the adsorbent and becoming a desulfurization by-product as shown in Chemical Reaction Formula 1 below.

[Chemical Reaction Formula 1]

2Fe ₂ O ₃ + 4SO ₂ + O ₂ = 4FeSO ₄

In addition, in this case, nitrogen oxides contained in the exhaust gas can be removed from the exhaust gas by reacting with the desulfurization by-product as shown in Chemical Reaction Formula 2 below to become a denitration by-product.

[Chemical Reaction Formula 2]

FeSO ₄ + NO = Fe(NO)SO ₄

Meanwhile, the adsorbent may be regenerated by the regenerant supplied into the reactor 200 by the regenerant supply unit 500 to be described later. As will be described later, the rejuvenating agent may be an aqueous alkali solution such as sodium hydroxide (NaOH). In addition, when a regenerant, which is an alkaline aqueous solution, is supplied into the reactor 200 by the regenerant supply unit 500, the regenerant chemically reacts with nitrogen oxides, sulfur oxides, desulfurization by-products and denitrification by-products contained in the exhaust gas. You can make a precursor. For example, when the adsorbent is iron oxide (Fe ₂ O ₃ ), the regenerating agent chemically reacts with nitrogen oxides, sulfur oxides, desulfurization by-products and denitrification by-products contained in the exhaust gas to form iron hydroxide (Fe(OH) ₃ ) as an adsorbent precursor. Can be created. In addition, iron hydroxide (Fe(OH) ₃ ) as an adsorbent precursor may be thermally decomposed by heat of exhaust gas inside the reactor 200 to be regenerated as iron oxide (Fe ₂ O ₃ ) as an adsorbent. Since the adsorbent is thus regenerated by the regenerating agent, there is no need to additionally supply the adsorbent.

As will be described later, before the exhaust gas is introduced into the reactor 200, a reducing agent such as ammonia (NH ₃ ) or a reducing agent precursor such as urea water serving as a reducing agent may be mixed with the exhaust gas by the reducing agent supply unit 400. have. In addition, nitrogen oxide contained in the exhaust gas in the reactor 200 may be reduced to nitrogen by a reducing agent as shown in Chemical Reaction Formula 3 below and removed from the exhaust gas.

[Chemical Reaction Formula 3]

4NO + 4NH ₃ + O ₂ = 4N ₂ + 6H ₂ O

In this case, the above-described catalyst included in the adsorption catalyst may help nitrogen oxide contained in exhaust gas to be reduced to nitrogen by a reducing agent and removed from the exhaust gas. Therefore, nitrogen oxides contained in the exhaust gas can be reduced to nitrogen by the reducing agent and the catalyst and removed from the exhaust gas.

The nitrogen oxide contained in the exhaust gas in the reactor 200 may be removed from the exhaust gas by reacting with a desulfurization by-product to become a denitration by-product, or reduced to nitrogen by a reducing agent and a catalyst and removed from the exhaust gas, as described above. .

The catalyst included in the adsorption catalyst may include at least one of vanadium (V), tungsten (W), and titanium oxide (TiO ₂ ). In terms of improving the nitrogen oxide removal efficiency, the catalyst preferably includes both vanadium (V), tungsten (W), and titanium oxide (TiO ₂ ), and at this time, vanadium (V) is 0.1 to 5% by weight, 0.1 to 10% by weight of tungsten (W), and 85 to 99.8% by weight of titanium oxide (TiO ₂ ) may be included. The content of each component of the catalyst represents the maximum nitrogen oxide removal rate within the above range, and when vanadium (V) and tungsten (W) are present together, the reduction reaction of nitrogen oxides is further activated.

In particular, in the catalyst, if the content of vanadium (V) is less than 0.1% by weight, there is a concern that the activity of the nitrogen oxide reduction reaction may not appear. On the other hand, when the content of vanadium (V) exceeds 5% by weight, an excess of vanadium (V) forms SO ₃ by oxidizing SO ₂ in the exhaust gas, and the catalyst is poisoned by this SO ₃ to reduce nitrogen oxides. This can fall. On the other hand, when the content of tungsten (W) exceeds 10% by weight, it is not preferable when considering the aspect of improving the removal rate of nitrogen oxides versus cost.

For example, the catalyst consists of vanadium (V), tungsten (W), and titanium oxide (TiO ₂ ) in 5% by weight, 9% by weight, and 86% by weight, respectively, and vanadium (V) in titanium oxide (TiO ₂ ) as a support And tungsten (W) may be attached or inserted. However, the composition and shape of the catalyst is not particularly limited, and any composition and shape may be used as long as it includes at least one of vanadium (V), tungsten (W), and titanium oxide (TiO ₂ ).

In the adsorption catalyst, the mixing ratio of the adsorbent and the catalyst is preferably 1:0.1 to 1:10. When the mixing ratio of the adsorbent and the catalyst is outside the above range, the content of the adsorbent or the catalyst is too small, so that sulfur oxides or nitrogen oxides may not be sufficiently removed from the exhaust gas.

In addition, the adsorption catalyst may be used to remove sulfur oxides and nitrogen oxides at a temperature of 200°C to 500°C, preferably 250°C to 500°C, which is consistent with the catalytic activity temperature range of the nitrogen oxide reduction reaction. Therefore, when the temperature is out of the above range, the sulfur oxide adsorption reaction is not significantly affected, but the reduction reaction activity of the nitrogen oxide is less than 50%, which is not preferable because the nitrogen oxide reduction rate is rapidly reduced.

6 is a graph showing an experiment on whether the adsorbent contained in the adsorption catalyst affects the reduction rate of nitrogen oxides to nitrogen when an adsorbent and a catalyst are mixed to form an adsorption catalyst as in the present invention.

As shown, when only an adsorbent of iron oxide (Fe ₂ O ₃ ) is used, when only a catalyst consisting of vanadium (V), tungsten (W) and titanium oxide (TiO ₂ ) is used, and the adsorption catalyst according to the present invention Divided by use cases. In the case of using the adsorption catalyst according to the present invention, the mixture ratio of the catalyst and the adsorbent was divided into 1:0.1, 1:0.3, 1:1, 1:3 and 1:6, respectively. In addition, the reduction rate of nitrogen oxides to nitrogen by the same amount of a reducing agent was measured for exhaust gas without sulfur oxides and only nitrogen oxides.

As can be seen from the graph of FIG. 6, when only the adsorbent of iron oxide (Fe ₂ O ₃ ) is used, the reduction rate of nitrogen oxides was relatively low regardless of the temperature of the exhaust gas. And, when the temperature of the exhaust gas is lower than 200°C, the reduction rate of nitrogen oxides is lower when the adsorption catalyst according to the present invention is used than when only the catalyst is used. However, when the temperature of the exhaust gas is 200°C or more and less than 400°C, which is within the operating range of the exhaust gas treatment apparatus 100 according to the present invention, the reduction rate of nitrogen oxides is the case where only the catalyst is used and the adsorption catalyst according to the present invention is used. In the case of use, it was confirmed that there was no significant difference. Rather, in the temperature range of 200°C to 300°C, the nitrogen oxide reduction rate when using the adsorption catalyst according to the present invention was higher than the nitrogen oxide reduction rate when only the catalyst was used.

Accordingly, it can be seen that even if the adsorption catalyst according to the present invention in which an adsorbent and a catalyst are mixed is used, nitrogen oxide contained in exhaust gas can be reduced to nitrogen by an oxidizing agent and a catalyst, regardless of the adsorbent.

Table 1 below shows an experiment to find out the sulfur oxide adsorption capacity of the adsorption catalyst according to the present invention.

An experiment was conducted on exhaust gas containing only sulfur oxide, and as shown in Table 1 below, the amount of sulfur oxide adsorption when only an adsorbent such as copper oxide (CuO) was used was used. In addition, when only a catalyst composed of vanadium (V), tungsten (W) and titanium oxide (TiO ₂ ) is used, when only an adsorbent of iron oxide (Fe ₂ O ₃ ) is used, and the mixing ratio of the adsorbent and the catalyst is 1: It was divided into cases where the adsorption catalyst according to the present invention was used. And, in each case, compared with the case where only the adsorbent of copper oxide (CuO) was used, the increased sulfur oxide adsorption amount was expressed in %.

As can be seen from Table 1, when only the catalyst was used, sulfur oxides contained in the exhaust gas were not adsorbed at all. In addition, when only an adsorbent was used, iron oxide (Fe ₂ O ₃ ) was used as the adsorbent, and the amount of sulfur oxide adsorbed was three times higher than that when copper oxide (CuO) was used as the adsorbent. And, in the case of using the adsorption catalyst according to the present invention, the adsorption amount of sulfur oxides was smaller than that of using only the adsorbent of iron oxide (Fe ₂ O ₃ ), but the adsorption amount of sulfur oxides was less than when using only the adsorbent of copper oxide (CuO). It was twice as many.

Accordingly, it can be seen that even if the adsorption catalyst according to the present invention is used in which an adsorbent and a catalyst are mixed, the sulfur oxide contained in the exhaust gas can be adsorbed by the adsorbent regardless of the catalyst.

matter
The rate of increase in the amount of sulfur oxides adsorbed based on the adsorbent CuO

V(5),W(9)/TiO ₂ (catalyst)
0
Fe ₂ O ₃ (adsorbent)
300
V(5),W(9)/TiO ₂ +Fe ₂ O ₃ (1:1)
(Adsorption catalyst)
200

Fig. 7 is a measurement of the reduction rate of nitrogen oxides to nitrogen by the same amount of the reducing agent and the adsorption catalyst according to the present invention when nitrogen oxides are present in the exhaust gas and when both nitrogen oxides and sulfur oxides are present. It is a graph showing. The adsorption catalyst used in the experiment is a mixture of an adsorbent and a catalyst in a 1:1 ratio. As shown, it can be seen that even if sulfur oxides are included in the exhaust gas, the reduction rate of nitrogen oxides to nitrogen by the reducing agent and the adsorption catalyst according to the present invention does not change.

Based on the above points, the adsorption catalyst according to the present invention adsorbs sulfur oxides contained in exhaust gas and helps the reduction of nitrogen oxides to nitrogen by a reducing agent, thereby removing sulfur oxides and nitrogen oxides from exhaust gas. You can see that you can.

The reducing agent supply unit 400 may mix a reducing agent or a reducing agent precursor serving as a reducing agent in the exhaust gas before the exhaust gas is introduced into the reactor 200. The reducing agent mixed with the exhaust gas by the reducing agent supply unit 400 may be, for example, ammonia (NH ₃ ). However, the reducing agent is not particularly limited, and if it is mixed with the exhaust gas and can be removed from the exhaust gas by reducing the nitrogen oxide contained in the exhaust gas with the help of the catalyst of the adsorption catalyst in the reactor 200, it is well known. Anything of is possible. The cryogen precursor mixed in the exhaust gas by the reducing agent supply unit 400 may be, for example, urea water. When urea water is mixed with exhaust gas, it can become ammonia (NH ₃ ). However, the reducing agent precursor is not particularly limited, and any known reducing agent may be used as long as it is mixed with exhaust gas to become a reducing agent such as ammonia (NH ₃ ).

In the reactor 200, the reducing agent or the reducing agent precursor is mixed with the exhaust gas by the reducing agent supply unit 400 only in an amount that can be removed by the catalyst of the reducing agent and the adsorption catalyst. I can. In this case, some of the nitrogen oxides included in the exhaust gas may be removed by the catalyst of the reducing agent and the adsorption catalyst, and at least some of the remaining nitrogen oxides may be removed by the adsorbent of the adsorption catalyst. That is, as described above, some of the nitrogen oxides included in the exhaust gas may be removed from the exhaust gas by reducing the nitrogen oxides to nitrogen by a catalyst of a reducing agent and an adsorption catalyst. In addition, at least some of the remaining nitrogen oxides included in the exhaust gas are adsorbed by the sulfur oxides contained in the exhaust gas to the adsorbent through a chemical reaction to become a desulfurization by-product, and the desulfurization by-product reacts with the nitrogen oxides contained in the exhaust gas to a denitrification by-product. By doing this, it can be removed from the exhaust gas.

Thereby, since it is possible to use a relatively small amount of the reducing agent or the reducing agent precursor, the amount of the reducing agent or the reducing agent precursor mixed in the exhaust gas and the size of the reducing agent supply unit 400, for example, the size of the reducing agent storage tank 410 to be described later. You can make it small.

The reducing agent supply unit 400 may include a reducing agent storage tank 410 and a reducing agent supply pipe 420, as shown in FIGS. 2 to 5.

The reducing agent storage tank 410 may store a reducing agent such as ammonia (NH ₃ ) or a reducing agent precursor such as urea water. One side of the reducing agent supply pipe 420 is connected to the exhaust gas inlet 210 of the reactor 200, for example, the reactor 200 and is connected to the exhaust pipe PE through which the exhaust gas flows, and the other side is the reducing agent storage tank 410 Can be connected to In addition, one side of the reducing agent supply pipe 420 may be connected to the exhaust gas inlet 210 of the reactor 200. An opening/closing valve VL may be provided in the reducing agent supply pipe 420. Accordingly, when the opening/closing valve (VL) of the reducing agent supply pipe 420 is opened, the reducing agent or the reducing agent precursor stored in the reducing agent storage tank 410 as shown in FIG. 2 is transferred through the reducing agent supply pipe 420 to the reactor 200 It is supplied to the exhaust gas before flowing into it, and can be mixed with the exhaust gas. The reducing agent or the reducing agent precursor may be vaporized by a vaporizer (VP) as shown in FIGS. 4 and 5 before being mixed with the exhaust gas before flowing into the reactor 200.

The regenerant supply unit 500 may supply a regenerant capable of regenerating the adsorbent contained in the adsorption catalyst attached to the adsorption catalyst member 300 to the reactor 200. The regenerant supplied from the regenerant supply unit 500 may be, for example, an aqueous alkaline solution such as an aqueous sodium hydroxide (NaOH) solution.

As described above, when sulfur oxide contained in exhaust gas is adsorbed by a chemical reaction to an adsorbent included in the adsorption catalyst in the reactor 200, a desulfurization byproduct is generated as a reaction by-product. In addition, when the desulfurization by-product chemically reacts with nitrogen oxide contained in the exhaust gas, a denitration by-product is generated as a reaction by-product. In the process of treating the exhaust gas as described above, desulfurization by-products and denitrification by-products are generated, and the exhaust gas may include desulfurization by-products and denitrification by-products in addition to sulfur oxides and nitrogen oxides. When an alkaline aqueous solution such as sodium hydroxide (NaOH) aqueous solution is supplied as a regenerant to the exhaust gas inside the reactor 200, the regenerant chemically reacts with sulfur oxides, nitrogen oxides, desulfurization by-products and denitrification by-products contained in the exhaust gas. Precursors can be made. In addition, the adsorbent precursor may be pyrolyzed by heat of exhaust gas to be regenerated as an adsorbent. Since the adsorbent is thus regenerated by the regenerating agent, there is no need to additionally supply the adsorbent.

For example, when the adsorbent is iron oxide (Fe ₂ O ₃ ), when an alkaline aqueous solution such as sodium hydroxide (NaOH) aqueous solution is supplied into the reactor 200 as a regenerant, an alkaline aqueous solution such as sodium hydroxide (NaOH) aqueous solution, which is a regenerating agent, is By chemical reaction with sulfur oxides, nitrogen oxides, desulfurization by-products and denitrification by-products contained in exhaust gas, iron hydroxide (Fe(OH) ₃ ) may be produced as an adsorbent precursor. In addition, the adsorbent precursor, which is iron hydroxide (Fe(OH) ₃ ), can be pyrolyzed by heat of exhaust gas to be regenerated as iron oxide (Fe ₂ O ₃ ) as an adsorbent.

As described above, in order for the adsorbent precursor to be pyrolyzed by heat of the exhaust gas to be regenerated as the adsorbent, the temperature of the exhaust gas inside the reactor 200 may be 200°C or higher. When the temperature of the exhaust gas inside the reactor 200 is less than 200° C., the adsorbent precursor is not thermally decomposed by the heat of the exhaust gas. In this case, the temperature of the exhaust gas inside the reactor 200 may be 200° C. or more and less than 500° C. to enable thermal decomposition of the adsorbent precursor and reduction of nitrogen oxides to nitrogen by the catalyst of the reducing agent and the adsorption catalyst. When the temperature of the exhaust gas inside the reactor 200 is 500° C. or higher, thermal decomposition of the adsorbent precursor is performed, but the reduction of nitrogen oxides to nitrogen by the catalyst of the reducing agent and the adsorption catalyst is not performed.

The regenerating agent supplied from the regenerating agent supply unit 500 is not limited to the above-described sodium hydroxide (NaOH), and any alkali aqueous solution, for example, an aqueous potassium hydroxide (KOH) solution, may be used.

On the other hand, if the regenerating agent first reacts with the sulfur oxides contained in the exhaust gas, the adsorbent contained in the adsorption catalyst cannot be regenerated as described above. To prevent this, the regenerant supply unit 500 may supply the regenerant into the reactor 200 after the exhaust gas flows into the reactor 200. Accordingly, a regenerant may be supplied to a portion of the reactor 200 after the sulfur oxide contained in the exhaust gas has been removed from the exhaust gas to a predetermined degree.

As shown in FIGS. 1, 2, and 3, the regenerant supply unit 500 supplies a regenerant to a portion inside the reactor 200 that is a predetermined distance from the exhaust gas inlet 210 in the exhaust gas flow direction. I can. For example, as shown in Figs. 1, 2, and 3 (a), a plurality of adsorption catalyst members 300 are spaced apart from each other in the longitudinal direction or the width direction of the reactor 200 in the interior of the reactor 200. It can be provided. In this case, as shown in Figs. 1 and 2, in the regenerator supply unit 500, a part of the inside of the reactor 200 on the side of the exhaust gas outlet 220, for example, a regeneration agent in the upper part of the inside of the reactor 200 Can supply. In addition, as shown in (a) of FIG. 3, the regenerant supply unit 500 may supply the regenerant to the upper portion of the reactor 200. In addition, as shown in (b) of FIG. 3, a plurality of adsorption catalyst members 300 may be provided in the reactor 200 to be spaced apart from each other by a predetermined distance in the height direction of the reactor 200. In this case, a regenerant is not supplied to the inside of the reactor 200 with the adsorption catalyst member 300 provided at the bottom, and the adsorption catalyst member above the adsorption catalyst member 300 provided at the bottom ( A regenerant may be supplied to a portion of the reactor 200 provided with 300).

As shown in FIG. 2, the regenerant supply unit 500 may include a regenerant storage tank 510, a regenerant supply pipe 520, and a regenerant spray nozzle 530. The regenerating agent storage tank 510 may store a regenerating agent, which is an alkaline aqueous solution such as an aqueous sodium hydroxide (NaOH) solution. One side of the regenerant supply pipe 520 may be connected to the regenerant storage tank 510. The other side of the regenerator supply pipe 520 may pass through one surface of the reactor 200 and may be provided inside the reactor 200. For example, as shown in FIGS. 2 and 3A, the other side of the regenerator supply pipe 520 may pass through the upper surface of the reactor 200 and may be provided inside the reactor 200. In addition, the other side of the regenerator supply pipe 520 is branched into a plurality as shown in (b) of FIG. 3, and then passes through each side of the reactor 200, and above each of the plurality of adsorption catalyst members 300. It may be provided in a part of the inside of the reactor 200. An opening/closing valve VL may be provided in the regenerant supply pipe 520. Accordingly, when the on-off valve VL of the regenerant supply pipe 520 is opened, the regenerant stored in the regenerant storage tank 510 may flow through the regenerant supply pipe 520. The regenerant injection nozzle 530 may be provided in a portion of the regenerant supply pipe 520 provided in the reactor 200. The regenerant flowing through the regenerant supply pipe 520 may be injected into the reactor 200 by the regenerant spray nozzle 530. The regenerant may be vaporized by a vaporizer (VP) as shown in FIGS. 4 and 5 while flowing through the regenerant supply pipe 520 before being supplied into the reactor 200.

On the other hand, the mixing of the reducing agent or the reducing agent precursor into the exhaust gas by the reducing agent supply unit 400, and supply of the regenerating agent into the reactor 200 by the regenerating agent supply unit 500 are performed together as necessary. It can be lost or each can only be made.

When it is necessary to remove both sulfur oxides and nitrogen oxides from the exhaust gas, mixing of the reducing agent or the reducing agent precursor into the exhaust gas and supplying the regenerant into the reactor 200 may be performed together. In addition, when it is necessary to remove only sulfur oxide from the exhaust gas, since mixing of the reducing agent or the reducing agent precursor into the exhaust gas for nitrogen oxide removal is not required, only supply of the regenerating agent into the reactor 200 Can be done. And, when it is necessary to remove only nitrogen oxides from the exhaust gas, since regeneration of the adsorbent of the adsorption catalyst for sulfur oxide removal is not required, and supply of the regenerating agent into the reactor 200 is not required, the exhaust gas Only mixing of a reducing agent or a reducing agent precursor can be achieved. In addition, when regeneration of the adsorption catalyst, that is, regeneration of the adsorbent of the adsorption catalyst, is required, only the supply of the regenerant into the reactor 200 can be made.

The exhaust gas treatment apparatus 100 according to the present invention may, for example, be provided on a ship. In this case, the exhaust gas treatment device 100 may be provided before the turbocharger TC as shown in the upper part of FIG. 4, or provided behind the turbocharger TC as shown in the upper part of FIG. Can be.

When a ship passes an area that is both an Emission Control Area (ECA) and a Sulfur Emission Control Area (SECA), it is necessary to remove both sulfur oxides and nitrogen oxides from the exhaust gas. Therefore, in this case, the mixing of the reducing agent or the reducing agent precursor into the exhaust gas by the reducing agent supply unit 400 and the supply of the regenerating agent into the reactor 200 by the regenerating agent supply unit 500 can be performed together. have.

In addition, if the ship is not in an Emission Control Area (ECA) but passes through an area that is a Sulfur Emission Control Area (SECA), or if a fuel that does not meet the sulfur content standard is used, exhaust gas Only sulfur oxide may be removed from. Therefore, in this case, mixing of the reducing agent or the reducing agent precursor into the exhaust gas by the reducing agent supply unit 400 for removing nitrogen oxides is not required. In addition, in order to regenerate the adsorbent of the adsorption catalyst attached to the adsorption catalyst member 300, only the regenerator may be supplied into the reactor 200 by the regenerator supply unit 500.

In addition, when a ship passes through an area that is not an Emission Control Area (ECA) but is not a Sulfur Emission Control Area (SECA), only nitrogen oxides may be removed from the exhaust gas. Accordingly, in this case, since the adsorbent of the adsorption catalyst attached to the adsorption catalyst member 300 does not need to be regenerated, only the reducing agent or the reducing agent precursor may be mixed with the exhaust gas by the reducing agent supply unit 400.

In addition, even if a ship passes through an area that is not both an Emission Control Area (ECA) and a Sulfur Emission Control Area (SECA), when using high sulfur oil with a high sulfur content as fuel, sulfuric acid There is a need to respond to cargo emission regulations. In this case, since mixing of the reducing agent or the reducing agent precursor into the exhaust gas by the reducing agent supply unit 400 for removing nitrogen oxides is not required, in order to remove sulfur oxides and to regenerate the adsorbent of the adsorption catalyst, Only the supply of the regenerant into the reactor 200 by the supply unit 500 may be made.

Exhaust gas treatment method

An embodiment of the exhaust gas treatment method according to the present invention may include a mixing step (S100), an inflow step (S200), a treatment step (S300), and a regeneration step (S400).

In the mixing step (S100), a reducing agent or a reducing agent precursor serving as a reducing agent may be mixed with the exhaust gas. For example, as described above, before the exhaust gas is introduced into the reactor 200, by the reducing agent supply unit 400, a reducing agent such as ammonia (NH ₃ ) or a reducing agent precursor such as urea water serving as a reducing agent is It may be mixed with the exhaust gas flowing through the exhaust pipe (PE) connected to the discharge device (ED).

Meanwhile, in the mixing step (S100), the reducing agent or the reducing agent precursor is mixed with the exhaust gas only in an amount that can be removed by the catalyst of the reducing agent and the adsorption catalyst in part of the nitrogen oxide contained in the exhaust gas in the processing step (S300). can do.

In this case, some of the nitrogen oxides contained in the exhaust gas are removed by the catalyst of the reducing agent and the adsorption catalyst in the treatment step (S300), and at least some of the remaining nitrogen oxides are removed by the adsorbent of the adsorption catalyst in the treatment step (S300). Can be. That is, as described above, some of the nitrogen oxides included in the exhaust gas may be removed from the exhaust gas by reducing the nitrogen oxides to nitrogen by a catalyst of a reducing agent and an adsorption catalyst. In addition, at least some of the remaining nitrogen oxides included in the exhaust gas are adsorbed by the sulfur oxides contained in the exhaust gas to the adsorbent through a chemical reaction to become a desulfurization by-product, and the desulfurization by-product reacts with the nitrogen oxides contained in the exhaust gas to form a denitration by-product. By doing this, it can be removed from the exhaust gas.

Accordingly, since a relatively small amount of the reducing agent or precursor can be used, the amount of the reducing agent or the reducing agent precursor mixed in the exhaust gas and the size of the reducing agent supply unit 400, such as the size of the reducing agent storage tank 410, can be reduced. I can...

In the introduction step (S200), the exhaust gas in which the reducing agent or the reducing agent precursor is mixed in the mixing step (S100) may be introduced into the reactor 200 as described above. For example, through the exhaust gas inlet 210 connected to the exhaust pipe PE, the exhaust gas mixed with a reducing agent or a reducing agent precursor may be introduced into the reactor 200.

In the treatment step (S300), nitrogen oxides contained in exhaust gas may be removed from the inside of the reactor 200 by a reducing agent and an adsorption catalyst. For example, a reducing agent such as ammonia (NH ₃ ) mixed in the exhaust gas is converted to nitrogen oxides contained in the exhaust gas with the help of the catalyst of the adsorption catalyst attached to the adsorption catalyst member 300 provided inside the reactor 200. By reducing to, nitrogen oxides contained in the exhaust gas can be removed from the exhaust gas.

In addition, in the processing step (S300), the sulfur oxide contained in the exhaust gas may be adsorbed by the adsorption catalyst in the reactor 200 and nitrogen oxide contained in the exhaust gas may be sequentially removed. For example, sulfur oxide contained in exhaust gas is adsorbed to the adsorbent of the adsorption catalyst attached to the adsorption catalyst member 300 provided inside the reactor 200 by a chemical reaction to become a desulfurization by-product, thereby removing the sulfur oxide from the exhaust gas. I can. In addition, the desulfurization by-product reacts with the nitrogen oxide contained in the exhaust gas to become a denitration by-product, so that nitrogen oxides can be removed from the exhaust gas.

In the regeneration step (S400), a regenerant may be supplied into the reactor 200 to regenerate the adsorption catalyst, that is, the adsorbent of the adsorption catalyst. For example, in the regeneration step (S400), an aqueous alkali solution such as sodium hydroxide (NaOH) may be supplied into the reactor 200 by the regenerant supply unit 500.

In addition, the regeneration step (S400) may include a precursor generation step (S410) and a pyrolysis step (S420).

In the precursor generation step (S410), the regenerator supplied into the reactor 200, nitrogen oxides, sulfur oxides, and desulfurization by-products and denitrification by-products made in the above-described processing step (S300) are chemically reacted, For example, it is possible to prepare an adsorbent precursor such as iron hydroxide (Fe(OH) ₃ ).

In the pyrolysis step (S420), the adsorbent precursor such as iron hydroxide (Fe(OH) ₃ ) made in the precursor generation step (S410) is pyrolyzed by heat of the exhaust gas, and can be regenerated with an adsorbent such as iron oxide (Fe ₂ O ₃ ). have. To this end, the temperature of the exhaust gas inside the reactor 200 may be 200° C. or higher to allow thermal decomposition of the adsorbent precursor. In this case, the temperature of the exhaust gas inside the reactor 200 may be 200° C. or more and less than 500° C. to enable thermal decomposition of the adsorbent precursor and reduction of nitrogen oxides to nitrogen by a reducing agent and a catalyst.

As described above, when the exhaust gas treatment device according to the present invention is used, sulfur oxides and nitrogen oxides can be simultaneously removed from exhaust gas with one exhaust gas treatment device.

The exhaust gas treatment apparatus described above is not limitedly applicable to the configuration of the above-described embodiments, but the embodiments may be configured by selectively combining all or part of each of the embodiments so that various modifications can be made. have.

100: exhaust gas treatment device 200: reactor
210: exhaust gas inlet 220: exhaust gas outlet
230: treatment by-product outlet 300: adsorption catalyst member
400: reducing agent supply unit 410: reducing agent storage tank
420: reducing agent supply pipe 500: regenerating agent supply unit
510: regeneration agent storage tank 520: regeneration agent supply pipe
530: regenerant injection nozzle ED: exhaust gas discharge device
ME: Main engine GE: Power generation engine
PE: Exhaust pipe PD: Exhaust gas discharge pipe
TC: Turbocharger VL: On-off valve
PL: Drain pipe TB: Treatment by-product collection tank
VP: carburetor

Claims (17)

A reactor through which exhaust gas is introduced; And
An adsorption catalyst member provided inside the reactor; Including,
An adsorption catalyst is attached to the adsorption catalyst member,
The adsorption catalyst adsorbs and removes sulfur oxides contained in exhaust gas, while simultaneously reducing and removing nitrogen oxides included in exhaust gas with a reducing agent. An exhaust gas treatment device that further removes nitrogen oxides. The method of claim 1, wherein the adsorption catalyst comprises: an adsorbent that causes sulfur oxides contained in exhaust gas to be adsorbed by a chemical reaction to become a desulfurization by-product, and the desulfurization by-product chemically reacts with nitrogen oxides contained in the exhaust gas to become a denitration by-product; , An exhaust gas treatment device comprising a catalyst that helps to reduce nitrogen oxides contained in exhaust gas to nitrogen by a reducing agent. The exhaust gas treatment apparatus according to claim 2, wherein a mixing ratio of the adsorbent and the catalyst is 1:0.1 to 1:10. The exhaust gas treatment apparatus according to claim 2, wherein the adsorbent comprises at least one of iron oxide (Fe ₂ O ₃ ), copper oxide (CuO), and cerium oxide (CeO). The exhaust gas treatment apparatus of claim 2, wherein the catalyst comprises at least one of vanadium (V), tungsten (W), and titanium oxide (TiO ₂ ). The apparatus of claim 2, further comprising: a regenerating agent supply unit for supplying a regenerating agent for regenerating the adsorbent into the reactor; Exhaust gas treatment apparatus further comprising a. 7. Exhaust gas treatment device. The exhaust gas treatment apparatus according to claim 7, wherein the regenerant is an aqueous alkali solution. The exhaust gas treatment apparatus according to claim 7, wherein the temperature of the exhaust gas inside the reactor is 200°C or more and less than 500°C to enable thermal decomposition of the adsorbent precursor and reduction of nitrogen oxides to nitrogen by the reducing agent and catalyst. delete delete delete delete delete delete delete delete

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