KR20140065119A - Apparatus for purificating exhaust gas - Google Patents

Abstract

The present invention relates to an exhaust gas treatment device for treating exhaust gas discharged from an engine of a vessel comprising: a first treating part installed on a path for discharging the exhaust gas to treat nitrogen oxides (NOx) contained in the exhaust gas by spraying a reducing agent; a second treating part connected to the first treating part to remove sulfur oxides (SOx) downwards by contacting sulfur oxides (SOx) contained in the exhaust gas by spraying a cleaning solution; and a third treating part installed in the upper side of the second treating part to collect minute particles contained in the exhaust gas flowing from the second treating part to the upper side. Therefore, according to the present invention, provided is the exhaust gas treatment device for improving the exhaust gas treatment efficiency by converting the sulfur oxides into hydrophile properties, and lowering the reaction temperatures of the nitrogen oxides through plasma treatment.

Description

[0001] APPARATUS FOR PURIFICATING EXHAUST GAS [0002]

The present invention relates to an exhaust gas treatment apparatus, and more particularly, to an exhaust gas treatment apparatus capable of improving treatment efficiency even at a relatively low temperature.

In ships using two-stroke large engines, low-grade fuel such as Bunker C oil or kerosene is mostly used, and the exhaust gas is discharged into the atmosphere containing many harmful substances due to the nature of high output. Representative harmful substances among these exhaust gases include fine dust, nitrogen oxides (NOx) and sulfur oxides (SOx).

On the other hand, in order to reduce the pollution caused by such exhaust gas, the regulation of exhaust gas directed to a ship is becoming more and more strict. In response to such regulations, the ship is equipped with an exhaust gas treatment apparatus using selective catalytic reduction (SCR).

1 schematically shows an example of a conventional exhaust gas processing apparatus.

1, a conventional exhaust gas processing apparatus 10 is an apparatus (not shown) for processing SOx and soot by spraying water while treating nitrogen oxides (NOx) through an SCR device 11 12), and the finally generated mist (white smoke) or soot is removed through a demister 13.

However, the conventional SCR apparatus 11 of the exhaust gas treatment apparatus 10 has a problem that the nitrogen oxide treatment efficiency is lowered at low temperatures. To solve this problem, a separate apparatus for maintaining the treatment conditions at a high temperature has been required.

Particulate matter (PM), which is substantially harmful to the human body through the sulfur oxide (SOx), the soot treatment device 12 and the demister 13 of the conventional exhaust gas treatment device 10, There is a problem that it is discharged in a state in which it is not discharged.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve such conventional problems, and it is an object of the present invention to improve the exhaust gas treatment efficiency by lowering the reaction temperature of the nitrogen oxide and converting the sulfur oxide into hydrophilicity through the plasma treatment, And an exhaust gas treatment device capable of improving the efficiency.

According to the present invention, there is provided an exhaust gas treatment apparatus for treating an exhaust gas discharged from an engine of a ship, the exhaust gas treatment apparatus being provided on a path through which the exhaust gas is discharged, spraying a reducing agent, (NOx) contained in the exhaust gas; A second processing unit connected to the first processing unit, for spraying a cleaning liquid and contacting the SOx contained in the exhaust gas and removing the SOx downward; And a third processing unit disposed above the second processing unit and configured to collect fine particles contained in the exhaust gas flowing upward from the second processing unit.

The first processing unit may further include: a pulse applying unit for applying a pulse voltage to the exhaust gas flowing; A reducing agent spraying unit for spraying a reducing agent toward the exhaust gas; And a catalyst part for increasing the reaction rate between the nitrogen oxide contained in the plasmaized exhaust gas and the reducing agent.

The pulse applying unit may include a pulse bar formed along the flow direction of the exhaust gas. And a power supply unit for supplying a pulse power to the pulse bar, wherein the reducing agent jet unit surrounds the outer surface of the pulse bar and applies a power from the power supply unit to the pulse bar, An injection port may be formed on the outer circumferential surface so that the reducing agent is injected in one direction.

The first processing unit may further include a chamber part electrically grounded to generate a plasma between the pulse bar provided in the first processing part and the reductant injecting part is formed of an insulating material so as to prevent electrical leakage between the pulse bar and the chamber part .

The second processing unit may include: a casing having an inlet port through which the exhaust gas flows; A plurality of cleaning liquid spray nozzles provided at an upper end of the casing and spraying a cleaning liquid downward; And an induction electrode surrounding the flow path of the cleaning liquid sprayed from the cleaning liquid spray nozzle to apply a high voltage so that the cleaning liquid is charged.

In addition, the cleaning liquid particles injected from the cleaning liquid injection nozzle may be refined by a high voltage applied from the induction electrode.

The third processing unit may include a plurality of dust collecting plates spaced upward from the cleaning liquid spraying nozzles so as to be spaced apart from each other; A water film formation inducing unit for injecting a cleaning liquid to form a water film on the dust collecting plate; A discharging part positioned between neighboring collecting plates to cause a discharge; And a high voltage application unit for applying a high voltage to the discharge unit.

According to the present invention, there is provided an exhaust gas processing apparatus capable of reacting nitrogen oxides with a reducing agent even at a low temperature, by making the exhaust gas plasma.

In addition, the treatment efficiency of sulfur oxides due to bonding with the washing water can be improved by transforming the sulfur oxide of the hydrophobic characteristic into hydrophilicity by converting the exhaust gas into plasma.

In addition, the binding strength with the sulfuric acid particles can be improved by charging the cleansing water.

Further, by collecting the fine particles on the dust collecting plate through the corona discharge, it is possible to treat fine particles harmful to the human body.

Further, the third treatment section is provided above the second treatment section for treating the sulfuric acid through the cleansing water spray, the wash water for forming a water film in the third treatment section flows into the second treatment section, and sulfuric acid is treated to improve the treatment performance .

Fig. 1 schematically shows an example of a conventional exhaust gas treating apparatus,
FIG. 2 is a schematic view of an exhaust gas treating apparatus according to an embodiment of the present invention,
Fig. 3 schematically shows a first treatment section of the exhaust gas treatment apparatus of Fig. 2,
Fig. 4 schematically shows a second treatment section of the exhaust gas treatment apparatus of Fig. 2,
5 schematically shows the structure of the cleaning liquid injection nozzle and the induction electrode of the exhaust gas processing apparatus of FIG. 2,
Fig. 6 is a schematic view showing a modification of the structure of the cleaning liquid injection nozzle and the induction electrode of the exhaust gas processing apparatus of Fig. 2,
Fig. 7 schematically shows a third processing section of the exhaust gas processing apparatus of Fig. 2;

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an exhaust gas processing apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 schematically shows an exhaust gas treating apparatus according to an embodiment of the present invention.

Referring to FIG. 2, an exhaust gas treating apparatus 100 according to an embodiment of the present invention is an apparatus for treating exhaust gas discharged from an engine E used in a ship. The exhaust gas treating apparatus 100 includes a first treating unit 110, 2 processing unit 120 and a third processing unit 130. [

Fig. 3 schematically shows a first treatment section of the exhaust gas treatment apparatus of Fig. 2; Fig.

Referring to FIG. 3, the first processing unit 110 is disposed on a path through which exhaust gas is exhausted and processes nitrogen oxides (NOx). The first processing unit 110 includes a pulse applying unit 111, a reducing agent spraying unit 115, (117).

The pulse application unit 111 includes a chamber unit 112, a pulse bar 113, and a power supply unit 114 for applying pulses to an exhaust gas flowing through the exhaust gas to be plasmaized.

The chamber part 112 primarily treats nitrogen oxides (NOx) contained in the exhaust gas flowing therein while preventing external leakage of the exhaust gas, and thereafter flows the exhaust gas flow path through a second processing part (120). The interior of the chamber part 112 is partitioned into a plurality of partitions, through which the exhaust gas flows.

On the other hand, the chamber part 112 maintains an electrically grounded state in order to generate a plasma with the pulse bar 113.

The pulse rod 113 converts nitrogen monoxide NO contained in the exhaust gas into nitrogen dioxide NO ₂ and converts the hydrophobic SOx to a hydrophilic sulfur oxide And is mounted along the longitudinal direction in each of the partitioned spaces of the chamber portion 112, as the exhaust gas is plasmaized.

The power supply unit 114 is electrically connected to each pulse bar 113 to apply a pulse voltage.

The reducing agent spraying part 115 is for spraying the reducing agent toward the exhaust gas for the treatment of the nitrogen oxide contained in the exhaust gas. The reducing agent spraying part 115 on the side to which the exhaust gas flows is mounted on the outer surface of the end of the pulse rod 113 and the reducing agent spraying part 115 is provided so that the reducing agent can spray the reducing agent toward the partitioned space side of the chamber part 112. [ A plurality of jetting openings 116 are formed on the outer circumferential surface of the ink jet head.

The injection port 116 is formed in a structure in which the injection direction of the reducing agent is perpendicular to the flow direction of the exhaust gas. The shape, position, number, and the like of the injection port 116 are not limited to the above, It is preferable to determine the flow rate and the like in consideration of the total.

Meanwhile, the reducing agent injected in this embodiment is one of ammonia (NH ₃ ) or hydrocarbon (HC), but is not limited thereto.

The reducing agent spraying part 115 is made of an insulating material and serves as an insulating part to prevent electrical leakage between the pulse rod 113 to which a high voltage is applied and the chamber part 112 to be grounded. In the present embodiment, the reducing agent spraying unit 115 is made of ceramic as an insulating material, but is not limited thereto.

The catalytic part 117 is for promoting the reaction between the nitrogen oxide contained in the exhaust gas and the reducing agent, but is not limited thereto. For example, platinum (Pt), vanadium (V), zeolite and the like may be used.

That is, as described above, in the present embodiment, the first processing unit 110 includes a post-processing apparatus using a selective catalytic reduction (SCR) composed of a reducing agent spraying unit 115 and a catalytic unit 117, And an application unit 111, which is a combined apparatus in which an exhaust system for converting exhaust gas into plasma is incorporated.

Fig. 4 schematically shows a second processing section of the exhaust gas processing apparatus of Fig. 2; Fig.

As shown in FIG. 4, the second processing unit 120 is installed at the rear end of the first processing unit 110 and is used for secondarily processing the gas exhausted after being primarily processed in the first processing unit 110 And includes a casing 121, a cleaning liquid injection nozzle 123, an induction electrode 124, and a packing unit 125.

The casing 121 is provided with a space for reprocessing the exhaust gas supplied from the first processing unit 110 after the exhaust gas is supplied thereto. The casing 121 is provided with a space therein, and a first processing unit 110, and an inlet 122 for receiving the exhaust gas is formed.

The exhaust gas flowing into the inlet 122 at the lower end of the casing 121 moves upward along the inner space of the casing 121 but the position of the inlet 122 of the casing 121 is not limited thereto.

5 schematically shows a structure of a cleaning liquid injection nozzle and an induction electrode of the exhaust gas processing apparatus of FIG.

5, a plurality of the cleaning liquid spray nozzles 123 are installed in the casing 121 to spray the cleaning liquid for treating the sulfur oxides (SOx) of the exhaust gas flowing into the casing 121 downward . The cleaning liquid jetting nozzle 123 is formed in a cylindrical shape and is formed long along the gravity direction.

The induction electrode 124 is for ringing the cleaning fluid sprayed from the cleaning fluid spray nozzle 123 and is disposed in a ring shape to surround each of the plurality of the cleaning fluid spray nozzles 123.

Fig. 6 schematically shows a modification of the structure of the cleaning liquid injection nozzle and the induction electrode of the exhaust gas processing apparatus of Fig. 2;

6, in the modification of the present embodiment, the induction electrodes 124 'are provided in the form of a pair of mutually spaced plates, and are disposed on both sides of the cleaning liquid injection nozzle 123' So that the cleaning liquid particles can be charged.

The packing part 125 is provided to increase the contact area between the cleaning liquid to be injected and the exhaust gas to be introduced. The packing part 125 is installed on a path through which the cleaning liquid flows in the casing 121 in a plurality of spherical shapes, A predetermined gap is formed. At this time, it is preferable that the gap of the packing part 125 is provided to such a degree that the cleaning liquid can sufficiently flow down.

Fig. 7 schematically shows a third processing section of the exhaust gas processing apparatus of Fig. 2;

7, the third processing unit 130 is for processing the fine particles that have not been processed in the second processing unit 120. The third processing unit 130 includes a dust collecting plate 131, a discharge unit 132, And a high-voltage applying unit 134. The high-

The dust collecting plate 131 is a plate-shaped member for collecting PM (Particulate Matter), that is, fine particles that can not be processed by the first processing unit 110 and the second processing unit 120, As shown in FIG.

The discharge unit 132 is disposed between neighboring dust collecting plates 131 to apply a high voltage from a high voltage applying unit 134 to cause a corona discharge with the dust collecting plate 131, Particulate matter (PM) in the exhaust gas is collected by the dust collecting plate 131.

The water film formation induction unit 133 injects the cleaning liquid into the dust collecting plate 131 to form a water film on the entire surface thereof to prevent the dust collecting plate 131 from being exposed and to allow the water film forming guide unit 133 to be detached from the dust collecting plate 131, And the cleaning liquid is a member for causing the second processing unit 120 to function as a cleaning liquid for treating sulfur oxides.

The high-voltage applying unit 134 is electrically connected to the discharging unit 132 to apply a high voltage.

Hereinafter, the operation of one embodiment of the exhaust gas treating apparatus 100 will be described.

First, the exhaust gas discharged through combustion in the engine enters the chamber part 112 of the first processing part 110. When the exhaust gas enters into a region divided into a plurality of chambers of the chamber portion 112, the pulse rod 113 supplied with the pulse power from the power supply portion 114 converts the exhaust gas into a plasma. At the same time, the reducing agent spraying part 115 injects the reducing agent in the direction perpendicular to the flow direction of the exhaust gas through the injection port 116.

At this time, the nitrogen oxide (NOx) contained in the exhaust gas to be converted into plasma is caused to react in the same manner as the following reaction formula so that the ratio of the nitrogen monoxide NO and the nitrogen dioxide NO ₂ becomes close to 50:50 , The following reaction is the theoretical reaction, so that the ratio of nitrogen monoxide to nitrogen dioxide does not perfectly match 50:50.

[Reaction] 9NO + NO ₂ + 2O ₂ -> 5NO + 5NO ₂

On the other hand, at the same time as this reaction, the nature of the sulfur oxides (SO _X) contained in the exhaust gas inside the plasma screen is modified to a hydrophilic property (hydrophilic) in hydrophobicity (hydrophobic) properties.

In other words, the nitrogen oxide (NO) and the nitrogen dioxide (NO ₂ ) of the nitrogen oxide contained in the exhaust gas that is plasmaized by the pulse applying unit 111 become the same ratio and the characteristic of the sulfur oxide is modified to be hydrophilic .

The exhaust gas that has undergone the plasma treatment reacts with the reducing agent while passing through the catalytic portion 117 and is treated with nitrogen oxide. On the other hand, the reaction rate with a reducing agent is generally higher than that of nitrogen monoxide at a low temperature of 100 ° C to 200 ° C.

That is, in this embodiment, as the ratio of nitrogen dioxide is higher than that of the initial exhaust gas due to the plasma treatment, the nitrogen oxide is more easily reacted with the reducing agent as it passes through the catalytic portion 117 and the overall nitrogen oxide treatment performance is enhanced. Therefore, it is possible to easily process the nitrogen oxide without a separate apparatus for maintaining the first processing unit 110 at a high temperature.

The exhaust gas having passed through the first processing unit 110 and treated with nitrogen oxides flows into the casing 121 of the second processing unit 120 through the inlet 122 and flows into the casing 121 in which the cleaning liquid injection nozzle 123 is located, As shown in FIG.

At this time, the cleaning liquid injecting nozzle 123 injects the cleaning liquid downward so that the sulfur oxide is combined with the cleaning liquid to be processed. Further, since the packing portion 125 filled in the casing 121 further increases the contact area between the sulfuric acid and the cleaning liquid, the sulfuric acid treatment performance can be increased.

At the same time, a voltage is applied through the induction electrode 124 to charge the injected cleaning liquid. The coupling efficiency between the washing water particles and the sulfur oxide in the charged state by the induction electrode 124 is further increased. At the same time, the sulfur oxides (SOx) contained in the exhaust gas are reformed to have hydrophilicity in the first processing section 110 and pass through the second processing section 120, so that the hydrophilically modified sulfur oxides are more easily combined with the cleaning liquid particles .

In other words, the improved processing performance of the sulfur oxides in the second processing unit 120 will be described again. When the cleaning water particles are charged by the induction electrode 124, the binding force with sulfur oxides increases. At the same time, ), The sulfur oxide is reformed to be hydrophilic and the probability of bonding with the washing water particles becomes higher, so that the treatment performance of the overall sulfur oxide in the second treatment section 120 is improved.

The exhaust gas in the state where the sulfuric acid treatment is completed in the second processing unit 120 moves upward and enters the third processing unit 130. The high voltage application unit 134 of the third processing unit 130 applies a high voltage to the discharge unit 132 to generate a corona discharge with the dust collecting plate 131.

Particulate matter (PM), that is, fine particles contained in the exhaust gas passing through the space between the dust collecting plates 131 is collected on the dust collecting plate 131 by the corona discharge. Simultaneously with the collection of the fine particles, the water film formation inducing unit 133 injects the washing water toward the dust collecting plate 131 to form a water film on the entire surface of the collecting plate 131. Therefore, the fine particles can not be directly contacted with the dust collecting plate 131 by the water film formed on the dust collecting plate 131, and are dropped downward together with the water film flowing down.

On the other hand, the cleaning liquid, which is separated from the dust collecting plate 131 after the formation of the water film, flows into the second processing unit 120 and binds to the sulfur oxide, thereby further improving the treatment efficiency of the sulfur oxide.

Therefore, according to the exhaust gas processing apparatus of this embodiment, nitrogen oxide and sulfur oxide can be treated with improved performance, particulate matter can be removed, and the purified gas can be discharged to the outside.

The scope of the present invention is not limited to the above-described embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

100: An exhaust gas treating apparatus according to an embodiment of the present invention
110: first processing section 111: pulse applying section
115: Reducing agent dispensing part 117:
120: second processing unit 130: third processing unit

Claims (7)

1. An exhaust gas processing apparatus for processing exhaust gas discharged from an engine of a ship,
A first processing unit installed on a path through which the exhaust gas is exhausted and processing nitrogen oxide (NOx) contained in the exhaust gas by injecting a reducing agent;
A second processing unit connected to the first processing unit, for spraying a cleaning liquid and contacting the SOx contained in the exhaust gas and removing the SOx downward;
And a third processing unit disposed above the second processing unit for collecting fine particles contained in the exhaust gas flowing upward from the second processing unit. The method according to claim 1,
Wherein the first processing unit includes: a pulse applying unit for applying a pulse voltage to the exhaust gas flowing; A reducing agent spraying unit for spraying a reducing agent toward the exhaust gas; And a catalytic part for increasing the reaction rate between the nitrogen oxide contained in the plasmaized exhaust gas and the reducing agent. 3. The method of claim 2,
Wherein the pulse applying unit comprises: a pulse bar formed to be long along the flow direction of the exhaust gas; And a power supply unit for supplying a pulse power to the pulse bar,
Wherein the reducing agent jetting unit surrounds the outer surface of the pulse rod and applies a power source supplied from the power supply unit to the pulse bar so that a jetting port is formed on the outer circumferential surface so that the reducing agent is jetted in a direction perpendicular to the flow direction of the exhaust gas. The exhaust gas processing apparatus comprising: The method of claim 3,
Wherein the first processing unit further includes a chamber part electrically grounded to generate plasma between the pulse rods provided therein,
Wherein the reducing agent injecting unit is provided as an insulating material so as to prevent electrical leakage between the pulse bar and the chamber part. 5. The method according to any one of claims 1 to 4,
Wherein the second processing unit comprises: a casing having an inlet formed therein for introducing exhaust gas; A plurality of cleaning liquid spray nozzles provided at an upper end of the casing and spraying a cleaning liquid downward; And an induction electrode surrounding the flow path of the cleaning liquid sprayed from the cleaning liquid spray nozzle to apply a high voltage so that the cleaning liquid is charged. 6. The method of claim 5,
Wherein the cleaning liquid particle injected from the cleaning liquid injection nozzle is refined by a high voltage applied from the induction electrode. 6. The method of claim 5,
The third processing unit includes a plurality of dust collecting plates spaced apart from each other at a position spaced upward from the cleaning liquid spraying nozzle; A water film formation inducing unit for injecting a cleaning liquid to form a water film on the dust collecting plate; A discharging part positioned between neighboring collecting plates to cause a discharge; And a high voltage application unit for applying a high voltage to the discharge unit.

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