KR20210110908A - Photochemical Reaction Based Scrubber System - Google Patents

Abstract

Disclosed is a photochemical reaction-based scrubber system comprising: a purification module; a supply line for supplying a flue gas to an inlet of the purification module; an exhaust line for discharging the flue gas from an outlet of the purification module; a cleaning line for supplying cleaning water to a purification passage of the purification module; a water purifier for purifying wastewater discharged from the purification passage of the purification module; and a recirculation line recirculating the purified water of the water purifier back to a cleaning line. An objective of the present invention is to provide the photochemical reaction-based scrubber system which can increase space utilization within a ship and reduce a weight of the ship as much as possible.

Description

Photochemical Reaction Based Scrubber System

The present invention relates to a photochemical reaction-based scrubber system that satisfies the emission control values of sulfur oxides and nitrogen oxides for flue gas ships (0.1% or 0.5% m/m and Tier III, II).

The present invention decomposes / removes soot, ash, sulfur oxide (SOx), nitric oxide (NOx), etc., which are pollutants of the gas discharged from the combustion engine of a ship, using a physical and photochemical method. It relates to a scrubber system that can be

In accordance with the International Maritime Organization (IMO) ship flue gas emission regulations in 2020, the sulfur content limit has been strengthened. Alternatives such as replacement are suggested. Therefore, the method of complying with emission standards through the installation of a scrubber device is being used for reasons such as the price gap between low-sulfur oil and high-sulfur oil and reduction in installation investment/cargo capacity when using clean fuel.

A scrubber is an essential technology/device to purify exhaust gas. Existing flue gas treatment methods of ship equipment are open, closed, or hybrid chemical reactions through chemical reactions with water such as salt water and fresh water in the facility, such as wet or dry. By applying the purification method, it is possible to continuously use high sulfur oil through initial capital investment, thereby lowering fuel operating costs and satisfying the flue gas emission standards.

However, the existing scrubber system simply uses a chemical reaction between seawater and chemical liquids, so when decomposing harmful substances, a large amount of power is required other than power generation facilities for seawater, pumps and polluted water management devices, and engine operation, so the self-efficiency of the scrubber is reconsidered. It is in a state where it is difficult to respond and improve according to the strengthening of environmental regulations. In addition, since separate devices for sulfur oxides and nitrogen oxides are required, each system must be configured for each pollutant source, and a treatment system according to emission water regulations must be prepared. there was a problem with In addition, the existing photocatalytic scrubber system using ultraviolet light is being reviewed at the laboratory level due to the size limit on the purification efficiency of the material, the slow purification reaction rate, and the problem of light consumption.

The matters described as the above background art are only for improving the understanding of the background of the present invention, and should not be taken as acknowledging that they correspond to the prior art already known to those of ordinary skill in the art.

KR 10-2020-0001683 A

The present invention has been proposed to solve this problem, and it is a photo-oxidation type flue gas desulfurization/denitrification batch process that can be activated even in the visible light region to increase purification efficiency and reaction efficiency and increase energy efficiency, and is a photochemical reactor module type By applying a scrubber and varying the purification capacity according to the total amount of pollutants in the exhaust gas treatment through various selective combinations of purification modules, the engine can be operated at various operating points, and by enabling installation in various combinations, the space utilization in the ship is improved. It is intended to provide a photochemical reaction-based scrubber system that can increase the height and reduce the weight of the ship as much as possible.

The photochemical reaction-based scrubber system according to the present invention for achieving the above object is composed of a purification flow passage through which flue gas flows, a catalyst part providing a photooxidation material to the purification flow passage, and an irradiation part irradiating light to the purification flow passage, , a purification module provided with a flue gas inlet and outlet; a supply line for supplying flue gas to the inlet of the purification module; an exhaust line for discharging the flue gas from the outlet of the purification module; a cleaning line for supplying cleaning water to the purification passage of the purification module; a water purifier for purifying wastewater discharged from the purification passage of the purification module; and a recirculation line recirculating the purified water of the water purifier back to the washing line.

In the purification module, the exhaust gas inlet part is provided at the lower part and the outlet part is provided at the upper part, and a plurality of purification modules are connected to each other with the inlet part and the outlet part, and may be stacked in a vertical direction.

The exhaust line may be connected to the purification module located at the top.

The cleaning line is connected to each of the stacked purification modules, and the water purifier is connected to the purification module located at the bottom, and the washing water supplied to each purification module falls and can be drained to the water purifier through the purification module located at the bottom. .

The purification module is composed of a passive module and an active module, the catalyst part of the passive module is coated with a catalyst and installed inside the purification passage, and the catalyst part of the active module may be a supply mechanism that mixes the catalyst with washing water and supplies it to the purification passage have.

The active module may control the amount of catalyst supplied to the purification passage by controlling the amount of washing water supplied to the purification passage, and control the purification capacity of the active module by controlling the amount of catalyst supplied to the purification passage.

In the purification module, an exhaust gas inlet portion is provided at a lower portion and an outlet portion is provided at an upper portion, and a plurality of purification modules are stacked vertically with an inlet portion and an outlet portion connected to each other, and an active module may be disposed at the uppermost end.

The photooxidation reaction material of the catalyst part may be activated by light in the visible ray region to purify the flue gas, and the irradiator may irradiate the light in the visible ray region into the purification passage.

The photo-oxidation reaction material generates active species through the washing water, the active species decomposes sulfur oxides and nitrogen oxides in the flue gas in the purification passage, and the decomposed sulfur oxides and nitrates are ionized through the washing water and discharged to the water purifier. .

A filter is provided at the inlet of the purification module, and the flue gas may be supplied to the inlet of the purification module after particulate matter is purified by the filter.

A plurality of purification modules are stacked in the vertical direction to constitute a module tower, and a plurality of module towers are arranged laterally to constitute a module set, whereby the purification modules can be arranged in a matrix form.

Each of the purification modules may be connected to each other through a vertical connection line connecting the outlet and the inlet of the purification module arranged in the vertical direction and a lateral connection line connecting the outlet and the inlet of the purification module arranged laterally.

An on-off valve is provided in the vertical connection line and the side connection line, and the purification modules of the module set can be connected in series, parallel, or series-parallel through the control of the on-off valve.

An opening/closing valve is provided in the vertical connection line and the side connection line, and the number of gas flows through which the flue gas flows in the module set can be adjusted by controlling the opening/closing valve.

According to the photochemical reaction-based scrubber system of the present invention, by utilizing a photocatalyst that can be activated even in the visible light region, the efficiency of exhaust gas treatment is increased and energy efficiency is increased, and the capacity of exhaust gas treatment is increased through various combinations of purification equipment. By varying the engine, it is possible to operate the engine at various operating points, and by enabling installation in various combinations, it is possible to increase the space utilization in the vessel and to reduce the weight of the vessel as much as possible.

1 is a block diagram of a photochemical reaction-based scrubber system according to an embodiment of the present invention.
FIG. 2 is a view showing a purification module of the photochemical reaction-based scrubber system shown in FIG. 1. FIG.
3 to 4 are views showing a passive module and an active module of the photochemical reaction-based scrubber system shown in FIG. 1 .
5 is a view showing various stacking methods of the purification module.
6 to 8 are views showing various modes of the photochemical reaction-based scrubber system shown in FIG. 1 .

1 is a block diagram of a photochemical reaction-based scrubber system according to an embodiment of the present invention, FIG. 2 is a view showing a purification module of the photochemical reaction-based scrubber system shown in FIG. 1, and FIGS. 1 is a view showing a passive module and an active module of the photochemical reaction-based scrubber system shown in FIG. 1, and FIGS. 5 to 7 are views showing various modes of the photochemical reaction-based scrubber system shown in FIG.

The scrubber system of the present invention is excellent in energy efficiency by using a photocatalyst, which is a photooxidation reaction material that can be activated even in the visible light region, and has a very high purification efficiency compared to the conventional cleaning method using only a cleaning agent. Specifically, in the case of the conventional wet/dry method, there was a disadvantage in that a large amount of material was consumed and the operating cost increased as a by-product was generated/stored/cleaned. In the case of the present invention, as a photoactive method of decomposing/removing a contaminant with a light source, secondary contamination and by-products are small, and the regulation value (0.1% or 0.5% m/m) can be satisfied only by simple washing/recycling cleaning.

In addition, by utilizing the Z-scheme principle, which is a photoactive method, the effective surface area is maximized to increase the efficiency of reducing pollutants. In addition, it is possible to use a low-power LED from the conventional method of using a UV light source as a photocatalytic active light source, and by applying the polarization principle that uses a visible light source to activate light and evenly distribute the dose, increase the absorption efficiency and improve the purification ability. let it do And it corresponds to a scrubber structure that can actively purify according to the degree of flue gas emission in the existing simple stacked flue gas purification step. Physical [particle]-photochemical [gas] according to particle size and phase shape by applying sequential flue gas steps It corresponds to the reduction device of the treatment method.

1 is a block diagram of a photochemical reaction-based scrubber system according to an embodiment of the present invention. The photochemical reaction-based scrubber system according to the present invention includes a purification flow path through which flue gas flows, catalyst parts 322 and 342 that provide a photooxidation material as a photocatalyst to the purification flow path, and an irradiation part (L) for irradiating light to the purification flow path. and a purification module 300 having an exhaust gas inlet (E1) and an outlet (E2); a supply line for supplying the flue gas to the inlet (E1) of the purification module 300; an exhaust line 400 for discharging the flue gas from the outlet portion E2 of the purification module 300; a cleaning line for supplying cleaning water to the purification passage of the purification module 300; a water purifier 500 for purifying wastewater discharged from the purification passage of the purification module 300; and a recirculation line recirculating the purified water of the water purifier 500 back to the cleaning line.

The flue gas generated from the engine is a by-product produced by compressing/blasting crude oil together with intake air, and the gas emitted by consuming crude oil contains toxic gases depending on the content of sulfur and nitrogen in the crude oil.

As described above, there are pollutants such as NOX, SOX, HC, and PM in the flue gas, and it is an object of the present invention to purify them. As shown, the exhaust gas of the engine is introduced into the filter provided at the inlet part of the purification module through the exhaust line. The flue gas may be supplied to the inlet of the purification module after particulate matter (PM, SOOT) is purified by a filter made of a ceramic material. In the case of ceramic filters, only gases are filtered through physical/chemical adsorption. In addition, when replacing/regenerating a plurality of filters by arranging them in parallel, it is possible to prevent gas inflow and control the flow through a valve when replacing the filters later.

The purification module 300 is a chamber in which a flue gas purification passage is formed, and catalyst units 322 and 342 for providing a photooxidation reaction material to the purification passage are provided therein. In addition, an irradiating part L for irradiating light to the purification passage for activating the catalyst is provided.

And in the case of the purification module, an exhaust gas inlet part E1 and an outlet part E2 are provided. The filtered flue gas flows in through the inlet E1, and the flue gas rises due to the density difference and is purified through a catalyst activated by visible light. Then, the purified flue gas rises and is exhausted to the outside of the purification module through the outlet part E2.

A supply line for supplying flue gas is connected to the inlet portion E1 of the purification module, and a filter 200 is provided on the supply line. And an exhaust line 400 for discharging the flue gas from the outlet portion E2 of the purification module is provided. The cleaning line supplies cleaning water to the purification passage of the purification module so that the flue gas can be decomposed well, and the water purifier 500 purifies the wastewater discharged from the purification passage of the purification module. A recirculation line for recirculating the purified water of the water purifier back to the washing line is provided. The washing water is converted into active species by the catalyst, and the active species is converted back to water after purifying the pollutants in the flue gas. Therefore, the water purifier filters out the water and returns it to the water purifier for recycling.

As shown in FIGS. 1 and 2 , the purification module 300 has an exhaust gas inlet E1 at a lower portion and an outlet E2 at an upper portion, and a plurality of purification modules 300 include an inlet E1 and an outlet. The parts E2 are interconnected and may be stacked vertically. And the flue gas flows into the lowest purification module and then rises, and by repeatedly going through several stages of purification, it can be completely purified.

In addition, the exhaust line 400 is connected to the purification module located at the top so that in the case of gas exhausted to the outside, all harmful substances are removed and exhausted. Through this structure, in the case of a large vessel with a large flue gas capacity, by increasing the number of stacked purification modules, there is no shortage of purification capacity. is to make it possible

On the other hand, when the purification modules 300 are stacked, a cleaning line is connected to each of the stacked purification modules 300 to supply cleaning water to each purification module 300, so that each purification module 300 is activated by a catalyst. to make it happen And since the washing water falls in a gravity direction different from the flue gas inside the purification module, it is continuously purified while going downward. In the purification module at the bottom, the used washing water is sent to the water purifier. That is, the water purifier may be connected to the purification module located at the bottom, and the washing water supplied to each purification module may fall and be drained to the water purifier through the purification module located at the bottom.

On the other hand, the purification module is composed of a passive module 320 and an active module 340, as shown in FIG. 3, the catalyst part 322 of the passive module 320 is coated with a catalyst and installed inside the purification passage, as shown in FIG. Similarly, the catalyst unit 342 of the active module 340 may be a supply mechanism for mixing the catalyst with the washing water and supplying it to the purification passage. The active module 340 may control the amount of catalyst supplied to the purification flow path by controlling the amount of washing water supplied to the purification flow path, and control the purification capacity of the active module by controlling the amount of catalyst supplied to the purification flow path. have.

In the case of the passive module 320, the catalyst unit 322 is installed as hardware on the purification passage and generates active species through a photocatalyst. Active species react with sulfur oxides/nitrogen oxides in flue gas to decompose. In addition, a light source is disposed in the center to increase the production efficiency of the active species, and the contact area/contact time can be controlled to increase the reaction efficiency.

The process of generating active species through the photocatalyst is as follows.

In addition, the process of decomposition of sulfur oxides is as follows.

The process of decomposition of nitric oxide is as follows.

Through the above process, sulfur oxides and nitrogen oxides are decomposed into ions, and the ions are discharged together with the washing water, making it possible to remove nitrogen oxides and sulfur oxides from the flue gas.

In the case of washing water, although it exists to form active species, the washing water is also supplied for the purpose of washing sulfur oxides and nitroxides reacted with the active species. As shown below, the by-products are discharged in an ionizable state by water.

In the case of the active module 340, it does not have a fixed catalyst like a passive module, but is a module for additional purification performance control by supplying and controlling the catalyst by adding a catalyst to the washing water as shown in FIG. 4 . The active module 340 directly sprays the washing water stirred with the additive for purification.

_{SO 2} in SOx is dissolved in water and converted to sulfuric acid and removed, which can be removed with sodium sulfite when NaOH (chemical) is added to the washing water. In the active module, in addition to the photocatalytic reaction of the passive module, the water/chemical reaction works simultaneously.

In the case of washing water, it is supplied for the purpose of washing sulfur oxides and nitroxides reacted with active species, and by-products can be ionized by water.

The by-products washed through the washing water in each purification module may be individually collected at the bottom of the system through a pipe line, or it may be collected sequentially downward through the purification module below. And in the bottom purification module, nitrate (NO ₃ ), sulfate (SO ₄ ,SO ₃ ), sodium sulfite (Na ₂ SO ₃ ) is stored in the form of an aqueous solution containing.

The water purifier 500 separates the aqueous solution in the washing wastewater into waste and washing water, the waste tank T3 stores the waste, and the washing water tank T1 stores the washing water for supply to each module. In the case of the pumps P1 and P2, it is for circulating the washing water of the washing water tank, and the additive tank T2 is a catalyst in the washing water circulated through the pump P2 to increase the additional purification performance of the active module 340. and NaOH. And it has a structure that uniformly sprays additives to agitate, and implements photocatalyst powder and NaOH powder storage functions as an internal storage for additive storage.

In the case of purified gas, the fan is controlled to keep the flow of the entire system constant, and the fan control situation is implemented when replacing the ceramic filter, controlling the I/O valve in the passive module, and adding the active module. do.

The sensor (S) is used to determine whether the purification gas meets the environmental regulations, and measures whether it satisfies SOx emission: 0.50%m/m, NOx emission: 3.4g/kWh. It is to execute additional control according to satisfaction. When satisfied, the purification gas discharge rate is increased, and when dissatisfied, active module/circulation system is operated.

The gas pump P3 operates an additional purification function when the environmental regulation emission amount of the purified gas determined by the sensor S is not satisfied. It performs pump control for circulating the purified gas of the passive module, and performs valve control and fan control to prevent pressure rise in the module.

On the other hand, FIG. 5 is a view showing various stacking methods of purification modules, and the passive-active module combination according to the exhaust gas state (capacity, component) of the engine is applicable to ships of various sizes. In the purification module, the exhaust gas inlet portion is provided at the lower portion and the outlet portion is provided at the upper portion, the plurality of purification modules are stacked vertically with the inlet portion and the outlet portion connected to each other, and the active module may be disposed at the uppermost end.

In addition, the photocatalyst as a photooxidation material of the catalyst unit is activated in visible light to purify the flue gas, and the irradiator may irradiate the visible light to the inside of the purification passage.

In addition, the photocatalyst generates active species through washing water, the active species decomposes sulfur oxides and nitrogen oxides in the flue gas in the purification passage, and the decomposed sulfur oxides and nitrates are ionized through the washing water and discharged to the water purifier. .

Meanwhile, FIGS. 6 to 8 are views illustrating various modes of the photochemical reaction-based scrubber system shown in FIG. 1 .

A plurality of purification modules are stacked in the vertical direction to constitute a module tower (MT), and a plurality of module towers are arranged laterally to constitute a module set (MS), whereby the purification module can be arranged in a matrix form. In addition, each of the purification modules may be connected to each other through a vertical connection line connecting the outlet and the inlet of the purification module disposed in the vertical direction and a lateral connection line connecting the outlet and the inlet of the purification module disposed laterally.

In addition, an opening/closing valve is provided in the vertical connection line and the side connection line, and the purification modules of the module set may be connected in series, parallel, or series-parallel through the control of the opening/closing valve. In addition, an opening/closing valve is provided in the vertical connection line and the side connection line, and the number of gas flows through which the flue gas flows in the module set may be adjusted through the control of the opening/closing valve.

In the case of the purification module, each may be configured as a passive module or an active module, and a plurality of passive modules and active modules may be combined to form one purification module.

Specifically, in the case of FIG. 6, purification modules No. 1 and No. 5 are connected in series to create one gas flow. Similarly, purification modules No. 2 and No. 6 are connected in series. In this way, a total of four gas streams are formed, so that purification can be performed at a relatively high speed.

7 shows a method of making a gas flow by serially connecting in the order of No. 1-2 No. 6 No.-7 to create a gas flow, and serially connecting No. 3, No. 4 No. 8 No.-5 in the order. In this way, a total of two gas flows can be created. In this case, the speed is slower than that of FIG. 6, but the purification ability is doubled.

In the case of FIG. 8, the gas flow is formed in the order of No. 1, No. 2, No. 3, No. 4, No. 8, No. indicates the case.

In this way, it is possible to respond to various operating points of the engine by composing the purification module in a matrix and controlling the purification speed and purification capacity by controlling each valve.

According to the photochemical reaction-based scrubber system of the present invention, by utilizing a photocatalyst that can be activated even in the visible light region, the efficiency of exhaust gas treatment is increased and energy efficiency is increased, and the capacity of exhaust gas treatment is increased through various combinations of purification equipment. By varying the engine, it is possible to operate the engine at various operating points, and by enabling installation in various combinations, it is possible to increase the space utilization in the vessel and to reduce the weight of the vessel as much as possible.

Although shown and described with respect to specific embodiments of the present invention, it is understood in the art that the present invention can be variously improved and changed without departing from the spirit of the present invention provided by the following claims. It will be obvious to those of ordinary skill in the art.

100: engine 200: filter
300: purification module 400: exhaust line

Claims (14)

a purification module comprising a purification flow passage through which the flue gas flows, a catalyst part providing a photooxidation reaction material to the purification flow passage, and an irradiation part irradiating light to the purification flow passage, the purification module having an exhaust gas inlet and an outlet;
a supply line for supplying flue gas to the inlet of the purification module;
an exhaust line for discharging the flue gas from the outlet of the purification module;
a cleaning line for supplying cleaning water to the purification passage of the purification module;
a water purifier for purifying wastewater discharged from the purification passage of the purification module; and
A photochemical reaction-based scrubber system comprising a; a recirculation line recirculating the purified water of the water purifier back to the cleaning line. The method according to claim 1,
The purification module is a photochemical reaction-based scrubber system, characterized in that the flue gas inlet part is provided at the lower part and the outlet part is provided on the upper part, and a plurality of purification modules are connected to each other with the inlet part and the outlet part and are stacked in the vertical direction. 3. The method according to claim 2,
The exhaust line is a photochemical reaction-based scrubber system, characterized in that it is connected to the purification module located at the top. 3. The method according to claim 2,
The cleaning line is connected to each of the stacked purification modules, and the water purifier is connected to the purification module located at the bottom, and the washing water supplied to each purification module falls and is drained to the water purifier through the purification module located at the bottom. Photochemical reaction based scrubber system. The method according to claim 1,
The purification module is composed of a passive module and an active module, the catalyst part of the passive module is coated with a catalyst and installed inside the purification flow passage, and the catalyst part of the active module is a supply mechanism that mixes the catalyst with washing water and supplies it to the purification flow passage Photochemical reaction based scrubber system. 6. The method of claim 5,
The active module controls the amount of catalyst supplied to the purification passage by controlling the amount of washing water supplied to the purification passage, and controlling the purification capacity of the active module by controlling the amount of catalyst supplied to the purification passage. Photochemical reaction based scrubber system. 6. The method of claim 5,
The purification module is a photochemical reaction characterized in that the exhaust gas inlet part is provided at the lower part and the outlet part is provided on the upper part, a plurality of purification modules are stacked vertically with the inlet part and the outlet part connected to each other, and the active module is disposed at the uppermost part. based scrubber system. The method according to claim 1,
The photo-oxidation reaction material of the catalyst part is activated in the visible light region to purify the flue gas, and the irradiation unit irradiates the visible light region light into the purification passage. A photochemical reaction-based scrubber system. The method according to claim 1,
The photooxidation reaction material generates active species through washing water, the active species decomposes sulfur oxides and nitroxides in the flue gas in the purification flow path, and the decomposed sulfur oxides and nitroxides are ionized through the washing water and discharged to the water purifier. Photochemical reaction based scrubber system. The method according to claim 1,
A filter is provided at the inlet of the purification module, and the flue gas is supplied to the inlet of the purification module after particulate matter is purified by the filter. The method according to claim 1,
A photochemical reaction-based scrubber system, characterized in that a plurality of purification modules are stacked in the vertical direction to constitute a module tower, and a plurality of module towers are arranged laterally to constitute a module set, whereby the purification modules are arranged in a matrix form. 12. The method of claim 11,
Each purification module is connected to each other through a vertical connection line connecting the outlet and the inlet of the purification module arranged in the vertical direction and a lateral connection line connecting the outlet and the inlet of the purification module arranged laterally. Reaction-based scrubber system. 13. The method of claim 12,
A photochemical reaction-based scrubber system, characterized in that an on-off valve is provided in the vertical connection line and the side connection line, and the purification modules of the module set are connected in series, parallel, or series-parallel through the control of the on-off valve. 13. The method of claim 12,
A photochemical reaction-based scrubber system, characterized in that an on/off valve is provided in the vertical connection line and the side connection line, and the number of gas flows through which the flue gas flows in the module set is adjusted through the control of the on/off valve.

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