KR20160012613A - Apparatus for purifying marine exhaust gas - Google Patents

Abstract

The present invention relates to an apparatus for treating a marine exhaust gas, which improves desulfurization efficiency of a scrubber and also does not require an additional cooling tower by optimizing an exhaust gas temperature at an input stage and an output stage of the scrubber in treating an engine exhaust gas using an SCR apparatus and the scrubber. The apparatus for treating the marine exhaust gas according to the present invention includes: the SCR apparatus for removing nitrogen oxide included in the exhaust gas of an engine through selective catalytic reduction; the scrubber which removes sulfur oxide included in the exhaust gas by bringing the exhaust gas discharged from the SCR apparatus in contact with a scrubbing solution; a first heat exchange unit which is formed between the SCR apparatus and the scrubber, and cools the temperature of the exhaust gas discharged from the SCR apparatus; and a second heat exchange unit which is formed at a rear of the scrubber, and increases the temperature of the exhaust gas discharged from the scrubber into a second reference temperature.

Description

Technical Field [0001] The present invention relates to an apparatus for purifying marine exhaust gas,

The present invention relates to a ship exhaust gas treating apparatus, and more particularly, to an exhaust gas treating apparatus for a ship, which improves the desulfurization efficiency of a scrubber by optimizing an exhaust gas temperature at an input end and an output end of the scrubber in processing an engine exhaust gas using an SCR apparatus and a scrubber And more particularly, to a ship exhaust gas treatment apparatus capable of effectively recovering waste heat of exhaust gas and energy efficiency.

Nitrogen oxides and sulfur oxides contained in exhaust gases from ships are representative air pollutants subject to emission regulation by the International Maritime Organization (IMO).

The vessel is equipped with a selective catalytic reduction (SCR) unit (hereinafter referred to as SCR unit) and a scrubber to remove nitrogen oxides and sulfur oxides. The SCR apparatus is a device for removing nitrogen oxides using a reducing agent, and the scrubber is a device for removing sulfur oxides in the exhaust gas through a wet or dry method.

The 'Air pollution control system for ocean-going vessels' described in US Pat. No. 8,327,631 discloses a configuration in which a scrubber and SCR are sequentially disposed to remove contaminants in the combustion gas. On the other hand, the optimum operating temperature of the SCR is relatively higher than that of the scrubber. Accordingly, a quenching tower for lowering the temperature of the engine exhaust gas is provided at the front end of the scrubber, and a gas heater for raising the exhaust gas lowered by the scrubber to a predetermined temperature must be provided at the front end of the SCR Device complexity follows.

US Patent No. 8,327,631

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to improve the desulfurization efficiency of the scrubber by optimizing the temperature of the exhaust gas at the input and output stages of the scrubber in processing the engine exhaust gas using the SCR device and the scrubber It is an object of the present invention to provide a ship exhaust gas treatment apparatus capable of effectively recovering waste heat of exhaust gas and thereby improving energy efficiency.

According to an aspect of the present invention, there is provided an apparatus for treating a ship exhaust gas, comprising: an SCR device for removing nitrogen oxide contained in exhaust gas of an engine through a selective catalytic reduction reaction; A first heat exchange means provided between the SCR device and the scrubber for cooling the temperature of the exhaust gas discharged from the SCR device to a first reference temperature, And a second heat exchange unit provided at a rear end of the scrubber to raise the temperature of the exhaust gas discharged from the scrubber to a second reference temperature.

The first temperature sensor further comprises a first temperature sensor, a first circulation pipe, and a control device, wherein the first temperature sensor serves to measure the temperature of the exhaust gas supplied from the first heat exchange means to the scrubber, If the temperature of the exhaust gas input from the first temperature sensor is higher than the set reference temperature, the first on / off valve provided in the first circulation pipe is opened to exhaust the exhaust gas having a temperature higher than the first reference temperature through the first circulation pipe And the first circulation pipe is branched from the pipe between the first heat exchange means and the scrubber input end and connected to the first heat exchange means at one end thereof and the first circulation pipe is connected to the first heat exchange means via the first open / And is selectively opened according to the operation.

A second temperature sensor, a second circulation pipe, and a control device, wherein the second temperature sensor serves to measure a temperature of the exhaust gas discharged from the scrubber, If the temperature of the exhaust gas is lower than the set reference temperature, the second on-off valve provided in the second circulation pipe is opened so that exhaust gas having a temperature lower than the reference temperature is returned to the second heat exchange means through the second circulation pipe And the second circulation pipe is branched from the pipe extending from the discharge end of the second heat exchange means and connected at one end to the second heat exchange means and the second circulation pipe is selectively opened do.

The present invention also provides an apparatus for treating a ship exhaust gas, comprising: an SCR apparatus for removing nitrogen oxide contained in exhaust gas of an engine through a selective catalytic reduction reaction; A first heat exchange unit provided between the SCR unit and the scrubber for cooling the temperature of the exhaust gas discharged from the SCR unit and a second heat exchange unit provided at a rear end of the scrubber for controlling the temperature of the exhaust gas discharged from the scrubber, And the exhaust gas supplied to the scrubber is supplied to the exhaust gas flowing from the SCR device through the first bypass pipe to the scrubber and the exhaust gas supplied to the scrubber through the first heat exchanging means Is a mixed exhaust gas, is adjusted to a first reference temperature, and from the scrubber The exhaust gas to be discharged is an exhaust gas in which exhaust gas discharged directly from the scrubber through the second bypass pipe and exhaust gas discharged through the second heat exchange means are mixed without passing through the second heat exchange means, Another characteristic is that it is controlled.

The first temperature sensor further comprises a first temperature sensor, a first bypass pipe, and a control device, wherein the first temperature sensor serves to measure the temperature of the exhaust gas supplied to the scrubber from the first heat exchange means, And controlling the amount of exhaust gas passing through the first bypass pipe to be reduced by reducing the opening degree of the first bypass pipe when the temperature of the exhaust gas input from the first temperature sensor is higher than a set first reference temperature, When the temperature of the exhaust gas input from the first temperature sensor is lower than the set first reference temperature, the degree of opening of the first bypass valve is increased to control the amount of the exhaust gas passing through the first bypass pipe to increase, The first bypass piping serves to directly supply the exhaust gas discharged from the SCR device to the scrubber without passing through the first heat exchange means.

Wherein the second temperature sensor further comprises a second temperature sensor, a second bypass pipe, and a control device, wherein the second temperature sensor serves to measure a temperature of exhaust gas discharged from the scrubber, If the temperature of the exhaust gas input from the second temperature sensor is lower than a set second reference temperature, the degree of opening of the second bypass valve is reduced to reduce the amount of exhaust gas passing through the second bypass pipe, And controls the amount of exhaust gas passing through the second bypass pipe to be increased by increasing the degree of opening of the second bypass valve when the temperature of the exhaust gas is higher than a set second reference temperature, And discharges the exhaust gas from the second heat exchanger without passing through the second heat exchanger.

The first reference temperature is 70 to 120 deg. C, and the second reference temperature is 50 to 90 deg.

The electrolytic water treatment device according to any one of claims 1 to 3, wherein the electrolytic water is electrolytic water. And a scrubbing solution supply pipe for supplying the water to the scrubbing solution of the scrubber.

The ballast water treatment apparatus includes a seawater supply unit, an electrolysis device, and a ballast water tank. The seawater supply unit supplies seawater to the ballast water tank through a ballast water supply pipe, The electrolytic apparatus electrolyzes seawater supplied from the seawater supply unit to generate electrolyzed water. The generated electrolyzed water is supplied to the ballast water supply pipe and mixed with seawater , The scrubbing solution supply pipe is connected to one side of the ballast water supply pipe, one end of the scrubbing solution supply pipe is connected to the scrubber, and a part of the ballast water moved along the ballast water supply pipe is supplied to the scrubbing solution supply And the ballast water supplied to the scrubbing solution supply pipe is supplied to the scrubber as a scrubbing solution Class is.

The electrolytic apparatus is configured including an electrolytic cell equipped the cathode and the anode, and the electrolytic cell is generating electricity can be decomposed by applying power to the cathode and the anode in the water in a feed state, the positive electrode side, a chlorine ion (Cl ^-), An oxidizing agent including hypochlorous acid (HOCl) is generated, an alkaline agent including sodium hydroxide (NaOH) is generated on the cathode side, an oxidizer precursor supplying means and an alkaline agent precursor supplying means are further provided on one side of the electrolytic cell, And an alkaline agent precursor supply means respectively supply an oxidizing agent precursor and an alkaline agent precursor to the electrolytic bath, wherein each of the oxidizer precursor and the alkaline agent precursor is converted into an oxidizing agent and an alkaline agent upon electrolysis.

The oxidizing agent supply means and the alkaline agent supply means are further provided on one side of the scrubbing solution supply pipe, and it is possible to supply the oxidizing agent and the alkaline agent to the scrubbing solution through the oxidizing agent supplying means and the alkaline agent supplying means.

The ship exhaust gas treating apparatus according to the present invention has the following effects.

The desulfurization efficiency can be improved by optimizing the temperature of the exhaust gas supplied to the scrubber through the first heat exchanging means and the second heat exchanging means provided respectively at the front end and the rear end of the scrubber, and the white smoke generated from the exhaust gas discharged from the scrubber Can be reduced.

In addition, a quenching tower for lowering the temperature of the exhaust gas is not required, and the volume of the exhaust gas injected into the scrubber can be reduced without using a quenching tower. Thus, the optimum design of the scrubber can be achieved, It is possible to effectively recover the waste heat of the gas to enhance the energy efficiency.

In addition, since the ballast water containing the electrolyzed water produced in the ballast water treatment apparatus is used as the scrubbing solution required for the scrubber, no additional equipment for producing the scrubbing solution is required.

1 is a configuration diagram of a ship exhaust gas processing apparatus according to a first embodiment of the present invention;
Fig. 2 is a configuration diagram of a ship exhaust gas treating apparatus according to a second embodiment of the present invention; Fig.
3 is a configuration diagram of a ship exhaust gas treating apparatus according to a modified embodiment of the present invention.

The present invention is characterized in that the SCR apparatus and the wet scrubber are sequentially disposed to process the engine exhaust gas, the first heat exchanger and the second heat exchanger are provided at the front end and the rear end of the wet scrubber, respectively, The present invention proposes a technology that improves the desulfurization efficiency of the scrubber and reduces the occurrence of white smoke by optimizing the exhaust gas temperature and does not require a separate cooling tower. Hereinafter, a ship exhaust gas treating apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, a ship exhaust gas treating apparatus according to a first embodiment of the present invention includes an SCR apparatus 110, a scrubber 130, a first heat exchanging unit 120, and a second heat exchanging unit 140 .

The selective catalytic reduction (SCR) apparatus 110 is a device for reducing nitrogen oxides contained in the exhaust gas of the engine 10 to nitrogen and water vapor using a reducing agent such as ammonia water. Although not shown in the drawing, the SCR apparatus 110 is made up of an SCR reactor having a built-in catalyst, an alkaline supply apparatus for supplying an alkaline agent, and an alkaline supply nozzle for supplying an alkaline agent into the SCR reactor.

The scrubber 130 contacts the scrubbing solution with the exhaust gas discharged from the SCR device 110 to adsorb and remove sulfur oxides contained in the exhaust gas. The scrubbing solution may use seawater or ballast water. The use of the ballast water as the scrubbing solution is a constitution associated with the ballast water treatment apparatus, which will be described in detail in modified embodiments of the present invention described later.

The first heat exchange unit 120 is provided between the SCR unit 110 and the scrubber 130 to cool the temperature of the exhaust gas discharged from the SCR unit 110 to a predetermined temperature, The heat exchange unit 140 is provided at the rear end of the scrubber 130 to raise the temperature of the exhaust gas discharged from the scrubber 130 to a predetermined temperature. The first heat exchanging unit 120 and the second heat exchanging unit 140 may be plate-shaped or tubular. The heat exchange medium of the first heat exchanging unit 120 and the second heat exchanging unit 140 may be any one of water, steam, organic solvent used for organic Rankine cycle (ORC) generation, and carbon dioxide used for supercritical carbon dioxide Lt; / RTI >

The reason why the temperature of the exhaust gas is cooled to a predetermined temperature through the first heat exchanging means 120 is to adjust the temperature of the exhaust gas to the optimum operating temperature of the scrubber 130. Whereas the exhaust gas discharged from the SCR device 110 usually 230~450 ℃ of, when the temperature of the exhaust gas supplied to the scrubber 130 is more than 150 ℃ the SO ₂ in the exhaust gas that is not dissolved in the scrubbing solution There are characteristics. Accordingly, the first heat exchange unit 120 is configured to cool the exhaust gas discharged from the SCR unit 110 to 70 to 120 캜. Conventionally, a quenching tower is essential to reduce the volume and temperature of the exhaust gas. The quenching tower causes the shape of the scrubber and the piping to be complicated.

The first temperature sensor 121, the first circulation pipe 122, and the control device 150 are further provided to control the temperature of the exhaust gas supplied to the scrubber 130 via the first heat exchange unit 120 . The first temperature sensor 121 measures the temperature of the exhaust gas supplied from the first heat exchange unit 120 to the scrubber 130 and the controller 150 controls the temperature of the first temperature sensor Closing valve (123) provided in the first circulation pipe (122) is opened and the exhaust gas having a temperature higher than the first reference temperature is supplied to the first And is returned to the first heat exchange unit 120 through the circulation pipe 122. The first circulation pipe 122 is branched from the pipe between the first heat exchange unit 120 and the input end of the scrubber 130 and has one end connected to the first heat exchange unit 120, Is selectively opened according to the operation of the first opening / closing valve (123). The first reference temperature may be set in a temperature range of 70 to 120 ° C.

On the other hand, the reason why the exhaust gas of the scrubber 130 is raised to a predetermined temperature through the second heat exchange unit 140 is to prevent the occurrence of white smoke. The exhaust gas discharged from the scrubber 130 has a temperature of 30 to 50 ° C. In order to prevent the occurrence of white smoke, the temperature of the exhaust gas of the scrubber 130 should be adjusted to 50 to 90 ° C., Is configured such that the exhaust gas of the scrubber 130 is raised to 50 to 90 占 폚.

Similarly to the case of the first heat exchange unit 120, the second temperature sensor 141, the second circulation pipe 142, and the control unit 140 are provided for controlling the temperature of the exhaust gas discharged from the scrubber 130, (150) may be further provided. The second temperature sensor 141 measures the temperature of the exhaust gas discharged from the scrubber 130. The controller 150 controls the temperature of the exhaust gas input from the second temperature sensor 141, Closing valve 143 provided in the second circulation pipe 142 is opened so that the exhaust gas having a temperature lower than the reference temperature is discharged through the second circulation pipe 142 to the second heat exchange (140). ≪ / RTI > The second circulation pipe 142 is branched from the pipe extending from the discharge end of the second heat exchange means 140 and connected at one end to the second heat exchange means 140, And is selectively opened according to the operation of the two opening and closing valve 143. The second reference temperature may be set in a temperature range of 50 to 90 占 폚.

The configuration of the ship exhaust gas treating apparatus according to the first embodiment of the present invention has been described above. On the other hand, the temperature of the exhaust gas supplied to the scrubber and the temperature of the exhaust gas discharged from the scrubber can be adjusted through the method of the second embodiment described later in addition to the adjustment by the method of the first embodiment. The second embodiment is a method for controlling the temperature of the exhaust gas by bypassing a predetermined amount of exhaust gas when the heat exchange capacity of the first heat exchanging means and the second heat exchanging means is fixed. The ship exhaust gas treating apparatus according to the second embodiment of the present invention will now be described in detail.

Referring to FIG. 2, the apparatus for treating a ship exhaust gas according to the second embodiment of the present invention further includes a first bypass pipe 161 and a second bypass pipe 171 in comparison with the first embodiment, The first circulation pipe 122 and the second circulation pipe 142 of the first embodiment are omitted. A first bypass valve 162 and a second bypass valve 172 are provided at one side of the first bypass pipe 161 and the second bypass pipe 171, respectively.

As in the first embodiment, in the second embodiment, the first temperature sensor 121 for measuring the temperature of the exhaust gas supplied to the scrubber 130 and the temperature of the exhaust gas discharged from the scrubber 130 are measured A second temperature sensor 141 is provided. The first temperature sensor 121, the second temperature sensor 141, the first bypass valve 162, and the second bypass valve 172 are provided with a controller 180 interlocked with the first temperature sensor 121, the second temperature sensor 141, The controller 180 of the second embodiment controls the degree of opening and closing of the first bypass valve 162 and the second bypass valve 172 while the control device 150 of the embodiment controls the opening and closing operation of the opening and closing valve, And serves to control the amount of exhaust gas passing through the first bypass pipe 161 and the second bypass pipe 171. The role of the controller 180 of the second embodiment will be described later in detail.

The first heat exchanging means 120 and the second heat exchanging means 140 provided in the second embodiment have the same roles as those of the first embodiment. That is, the first heat exchange unit 120 is provided between the SCR unit 110 and the scrubber 130 to cool the temperature of the exhaust gas discharged from the SCR unit 110 to a predetermined temperature, The second heat exchange unit 140 is provided at a rear end of the scrubber 130 to raise the temperature of the exhaust gas discharged from the scrubber 130 to a predetermined temperature. However, unlike the first embodiment, the heat exchange capacity of the first heat exchanging unit 120 and the second heat exchanging unit 140 of the second embodiment can be fixed.

The first bypass pipe 161 serves to directly supply the exhaust gas discharged from the SCR apparatus 110 to the scrubber 130 without passing through the first heat exchange unit 120, And discharges the exhaust gas discharged from the scrubber 130 without passing through the second heat exchange means 140.

In the second embodiment, in the case of exhaust gas supplied to the scrubber 130, a certain amount of exhaust gas is supplied to the scrubber 130 via the first heat exchange unit 120, and a certain amount of exhaust gas is supplied to the first heat exchange unit The exhaust gas of the SCR device 110 is directly supplied to the scrubber 130 through the first bypass pipe 161 without passing through the bypass pipe 161. [ In the case of the exhaust gas discharged from the scrubber 130, a certain amount of exhaust gas is discharged through the second heat exchanging means 140, and a certain amount of exhaust gas is discharged without passing through the second heat exchanging means 140 .

Under such a configuration, the temperature of the exhaust gas supplied to the scrubber 130 and the temperature of the exhaust gas discharged from the scrubber 130 are controlled by the following method. At this time, it is assumed that the heat exchange amounts of the first heat exchanging means 120 and the second heat exchanging means 140 are fixed.

First, the temperature control of the exhaust gas supplied to the scrubber 130 will be described as follows. If the temperature of the exhaust gas input from the first temperature sensor 121 to the control device 180 is higher than the set first reference temperature, the control device 180 reduces the opening degree of the first bypass valve 162 The amount of exhaust gas passing through the first bypass pipe 161 is controlled to be reduced. On the contrary, if the temperature of the exhaust gas input from the first temperature sensor 121 to the control device 180 is lower than the set first reference temperature, the control device 180 controls the opening of the first bypass valve 162 So that the amount of exhaust gas passing through the first bypass pipe 161 is controlled to be increased.

Since the temperature of the exhaust gas of the SCR device 110 is higher than the temperature of the exhaust gas passing through the first heat exchange means 120, the exhaust gas from the SCR device 110 and the exhaust gas passing through the first heat exchange means 120 The temperature of the exhaust gas supplied to the scrubber 130 can be adjusted to match the first reference temperature by selectively controlling the degree of opening of the first bypass valve 162. Here, the degree of opening of the first bypass valve 162 according to the temperature measured by the first temperature sensor 121 may be set in advance, and the first reference temperature may be in a range of 70 to 120 캜 Can be set.

Next, the temperature control of the exhaust gas discharged from the scrubber 130 will be described. If the temperature of the exhaust gas input from the second temperature sensor 141 to the control device 180 is lower than the set second reference temperature, the control device 180 sets the degree of opening of the second bypass valve 172 to So that the amount of the exhaust gas passing through the second bypass pipe 171 is reduced. Conversely, when the temperature of the exhaust gas input from the second temperature sensor 141 to the control device 180 is higher than the set second reference temperature, the control device 180 determines the opening degree of the second bypass valve 172 So that the amount of exhaust gas passing through the second bypass pipe 171 is controlled to be increased.

Since the temperature of the exhaust gas of the scrubber 130 is lower than the temperature of the exhaust gas passing through the second heat exchanging means 140, the exhaust gas of the scrubber 130 and the exhaust gas passing through the second heat exchanging means 140 are mixed at an appropriate ratio The temperature of the exhaust gas discharged from the scrubber 130 can be adjusted to match the second reference temperature by selectively controlling the degree of opening of the second bypass valve 172. Here, the degree of opening of the second bypass valve 172 according to the temperature measured by the second temperature sensor 141 may be set in advance, and the second reference temperature may be set in a range of 50 to 90 DEG C Can be set.

The configuration of the ship exhaust gas treating apparatus according to the embodiment of the present invention has been described above. In the meantime, it has been described that the ballast water can be used as the scrubber solution supplied to the scrubber. However, in order to use the ballast water as the scrubber solution, the ballast water treatment apparatus can be connected and has the following structure in detail .

3, a scrubbing solution supply pipe 242 for supplying a scrubbing solution to the scrubber 130 is provided at one side of the scrubber 130, and one end of the scrubbing solution supply pipe 242 is connected to a ballast water supply device To the ballast water supply pipe (241). The ballast water supply pipe 241 is a pipe for supplying the ballast water mixed with the electrolyzed water and the seawater to the ballast water tank 230. A portion of the ballast water, Is supplied to the supply pipe 242 and acts as a scrubbing solution for the scrubber 130. The electrolytic water is electrolysis of seawater and includes an oxidizing agent such as chlorine ion (Cl ^- ), hypochlorous acid (HOCl), and an alkaline agent such as sodium hydroxide (NaOH) The ballast water treatment apparatus 20 will be described in detail.

The scrubbing solution supplied to the scrubber 130, that is, the ballast water is a mixture of electrolytic water and seawater. The electrolytic water contains oxidizing agents such as chlorine ions (Cl ^- ), hypochlorous acid (HOCl), and sodium hydroxide , A part of the nitrogen oxide contained in the engine exhaust gas reacts with the alkali agent in the scrubbing solution to be oxidized to nitrate ions (NO ₃ ^- ), and the sulfur oxides contained in the engine exhaust gas (SO ₃ ^- , SO ₄ ^2- ) or the like by reacting with an oxidizing agent or the like.

The ballast water treatment apparatus 20 will be described as follows. The ballast water treatment apparatus 20 basically produces ballast water and stores the ballast water in the ballast tank 230 in the vessel. The ballast water treatment apparatus 20 is configured in detail including a seawater supply unit 210, an electrolysis unit 220, and a ballast tank 230.

The seawater supply unit 210 serves to supply seawater to the ballast water tank 230 through the ballast water supply pipe 241. A part of the seawater supplied from the seawater supply unit 210 is supplied to the electrolytic apparatus 220 ). In addition, the ballast water tank 230 stores ballast water mixed with seawater and electrolyzed water.

The electrolytic apparatus 220 electrolyzes the seawater supplied from the seawater supply unit 210 to generate electrolyzed water. Specifically, the electrolytic apparatus 220 includes an electrolytic cell having a cathode and an anode. When power is applied to the cathode and the anode in a state where seawater is supplied to the electrolytic cell, seawater is electrolyzed. On the anode side, (Cl ^- ), hypochlorous acid (HOCl), and the like, and an alkali agent such as sodium hydroxide (NaOH) is produced on the cathode side. The oxidizing agent precursor supplying means 251 and the alkaline precursor supplying means 252 may be further provided to supply the oxidizing agent precursor and the alkaline agent precursor to the electrolytic bath in order to increase the amount of the oxidizing agent and the alkaline agent to be generated. Each of the oxidizer precursor and the alkaline precursor is converted to an oxidizing agent and an alkaline agent upon electrolysis.

The electrolytic water generated by the electrolytic apparatus 220, that is, the electrolytic water containing the oxidant and the alkaline agent described above is supplied to the ballast water supply pipe 241 and mixed with the seawater, The ballast water is stored in the ballast water tank 230 via the ballast water supply pipe 241.

Meanwhile, as described above, a scrubbing solution supply pipe 242 is connected to one side of the ballast water supply pipe 241, and one end of the scrubbing solution supply pipe 242 is connected to the scrubber 130. Accordingly, a part of the ballast water moved along the ballast water supply pipe 241 is supplied to the scrubbing solution supply pipe 242, and the ballast water supplied to the scrubbing solution supply pipe 242 is supplied as the scrubbing solution And supplied to the scrubber 130. An alkaline agent such as chlorine ion (Cl ^- ), hypochlorous acid (HOCl) and an oxidizing agent such as sodium hydroxide (NaOH) is supplied into the scrubbing solution supplied to the scrubber 130 through the scrubbing solution supply pipe 242 The nitrogen oxide contained in the engine exhaust gas when the engine exhaust gas and the scrubbing solution come into contact with each other in the scrubber 130 reacts with an alkali agent such as chloride ion (Cl ^- ), hypochlorous acid (HOCl) (NO ₃ ^- ), sulfur oxides contained in the engine exhaust gas are removed or absorbed in the form of sulfuric acid ions (SO ₃ ^- , SO ₄ ^2- ) or the like by reacting with an oxidizing agent or the like.

An oxidizing agent supply means 261 and an alkaline agent supply means 262 may be provided on one side of the scrubbing solution supply pipe 242 in order to improve the efficiency of oxidation reaction and absorption reaction by the oxidizing agent and the alkaline agent, The supply of the oxidizing agent and the supply of the alkaline agent to the scrubbing solution are enabled through the means 261 and the alkaline supplying means 262. [

Based on the above-described structure, the sulfur oxide contained in the exhaust gas of the engine is removed through the scrubber 130, and a part of the nitrogen oxide is primarily removed through the scrubber 130, It is possible to reduce the removal load, thereby reducing the amount of expensive SCR catalyst and reducing agent used. In addition, since the ballast water containing the electrolyzed water produced in the ballast water treatment apparatus 20 is applied as the scrubbing solution supplied to the scrubber 130, no separate facility for manufacturing the scrubbing solution is required.

10: engine 110: SCR device
120: first heat exchanging means 121: first temperature sensor
122: first circulation piping 123: first opening / closing valve
130: scrubber 140: second heat exchanging means
141: second temperature sensor 142: second circulation pipe
143: second open / close valve 150, 180: control device
161: first bypass piping 162: first bypass valve
171: second bypass piping 172: second bypass valve
210: Seawater supply part 220: Electrolysis device
230: ballast water tank 241: ballast water supply pipe
242: Scrubbing solution supply pipe 251: Oxidizing agent precursor supplying means
252: Alkali agent precursor supplying means 261: Oxidizing agent supplying means
262: Alkali agent supply means

Claims (11)

An SCR device for removing nitrogen oxide contained in exhaust gas of an engine through a selective catalytic reduction reaction;
A scrubber for contacting the exhaust gas discharged from the SCR device with a scrubbing solution to remove sulfur oxides contained in the exhaust gas;
First heat exchange means provided between the SCR device and the scrubber for cooling the temperature of the exhaust gas discharged from the SCR device to a first reference temperature; And
And a second heat exchange means provided at a rear end of the scrubber to raise the temperature of the exhaust gas discharged from the scrubber to a second reference temperature.
The apparatus according to claim 1, further comprising a first temperature sensor, a first circulation pipe, and a control device,
The first temperature sensor serves to measure the temperature of the exhaust gas supplied to the scrubber from the first heat exchange means,
Wherein the control device opens the first opening / closing valve provided in the first circulation pipe to exhaust the exhaust gas having a temperature higher than the first reference temperature, when the temperature of the exhaust gas input from the first temperature sensor is higher than the set reference temperature, 1 circulation pipe to the first heat exchange means,
The first circulation pipe is branched from the pipe between the first heat exchange means and the scrubber input and is connected to the first heat exchange means at one end. The first circulation pipe is selectively opened according to the operation of the first opening / closing valve Wherein the exhaust gas treating device is a vessel.
The apparatus according to claim 1, further comprising a second temperature sensor, a second circulation pipe, and a control device,
The second temperature sensor serves to measure the temperature of the exhaust gas discharged from the scrubber,
The control device may open the second on-off valve provided in the second circulation pipe to exhaust the exhaust gas having a temperature lower than the reference temperature, if the temperature of the exhaust gas input from the second temperature sensor is lower than the set reference temperature, To be returned to the second heat exchanging means through the circulation pipe,
The second circulation pipe is branched from the pipe extending from the discharge end of the second heat exchange means and one end thereof is connected to the second heat exchange means and the second circulation pipe is selectively opened according to the operation of the second on- Characterized in that the vessel exhaust gas treatment system comprises:
An SCR device for removing nitrogen oxide contained in exhaust gas of an engine through a selective catalytic reduction reaction;
A scrubber for contacting the exhaust gas with the scrubbing solution to remove sulfur oxides contained in the exhaust gas;
A first heat exchange unit provided between the SCR unit and the scrubber to cool the temperature of the exhaust gas discharged from the SCR unit; And
And second heat exchange means provided at a rear end of the scrubber to raise the temperature of the exhaust gas discharged from the scrubber,
The exhaust gas supplied to the scrubber is an exhaust gas mixed with an exhaust gas supplied from the SCR device to the scrubber through the first bypass pipe and an exhaust gas supplied to the scrubber through the first heat exchanger, ≪ / RTI &
The exhaust gas discharged from the scrubber is an exhaust gas mixed with exhaust gas discharged directly from the scrubber through the second bypass pipe and exhaust gas discharged through the second heat exchange means without passing through the second heat exchange means, And the temperature of the exhaust gas is adjusted to a reference temperature.
The apparatus according to claim 4, further comprising a first temperature sensor, a first bypass pipe, and a control device,
The first temperature sensor serves to measure the temperature of the exhaust gas supplied to the scrubber from the first heat exchange means,
Wherein the control device reduces the opening degree of the first bypass pipe to reduce the amount of exhaust gas passing through the first bypass pipe when the temperature of the exhaust gas input from the first temperature sensor is higher than a set first reference temperature, If the temperature of the exhaust gas input from the first temperature sensor is lower than the set first reference temperature, the degree of opening of the first bypass valve is increased to increase the amount of exhaust gas passing through the first bypass pipe Control,
Wherein the first bypass pipe serves to directly supply the exhaust gas discharged from the SCR device to the scrubber without passing through the first heat exchange means.
The apparatus according to claim 4, further comprising a second temperature sensor, a second bypass pipe, and a control device,
The second temperature sensor serves to measure the temperature of the exhaust gas discharged from the scrubber,
If the temperature of the exhaust gas input from the second temperature sensor is lower than the set second reference temperature, the control device reduces the opening degree of the second bypass valve and reduces the amount of exhaust gas passing through the second bypass pipe If the temperature of the exhaust gas input from the second temperature sensor is higher than the set second reference temperature, the degree of opening of the second bypass valve is increased to increase the amount of exhaust gas passing through the second bypass pipe In addition,
Wherein the second bypass piping serves to discharge the exhaust gas discharged from the scrubber without passing through the second heat exchange means.
The ship exhaust gas treatment system according to any one of claims 1 to 4, wherein the first reference temperature is 70 to 120 캜 and the second reference temperature is 50 to 90 캜.
The apparatus according to claim 1 or 4, further comprising: a ballast water processing apparatus for producing ballast water containing electrolyzed water;
A scrubbing solution supply pipe for supplying a ballast water containing electrolytic water produced by the ballast water treatment apparatus to the scrubbing solution of the scrubber is connected at one end to the ballast water treatment apparatus and at the other end to the scrubber Wherein the exhaust gas treatment apparatus comprises:
9. The ballast water treatment system according to claim 8, wherein the ballast water treatment device comprises a seawater supply part, an electrolysis device, and a ballast water tank,
The seawater supply unit supplies seawater to the ballast water tank through the ballast water supply pipe,
The ballast tank stores a ballast water in which seawater and electrolyzed water are mixed,
The electrolytic apparatus electrolyzes seawater supplied from the seawater supply unit to generate electrolyzed water. The generated electrolyzed water is supplied to the ballast water supply pipe and mixed with seawater,
Wherein the scrubbing solution supply pipe is connected to one side of the ballast water supply pipe, one end of the scrubbing solution supply pipe is connected to the scrubber, and a part of the ballast water moved along the ballast water supply pipe is connected to the scrubbing solution supply pipe And the ballast water supplied to the scrubbing solution supply pipe is supplied to the scrubber as a scrubbing solution.
10. The electrolytic apparatus according to claim 9, wherein the electrolytic apparatus comprises an electrolytic cell having a cathode and an anode, wherein the electrolytic cell generates electrolytic water by applying power to the cathode and the anode in a state where seawater is supplied, An oxidizing agent including ions (Cl ^- ) and hypochlorous acid (HOCl) is generated, an alkaline agent including sodium hydroxide (NaOH) is generated on the cathode side,
Wherein the oxidizer precursor supply means and the alkaline agent precursor supply means supply an oxidizer precursor and an alkaline precursor to the electrolytic bath, respectively, and each of the oxidizer precursor and the alkaline precursor, Wherein the oxidizing agent and the alkali agent are switched during electrolysis.
The method according to claim 8, further comprising an oxidizing agent supply means and an alkaline agent supply means at one side of the scrubbing solution supply pipe, wherein the oxidizing agent supply means and the alkaline agent supply means are capable of supplying the oxidizing agent and the alkaline agent to the scrubbing solution Characterized in that the vessel exhaust gas treatment system comprises:

Images