KR100723871B1 - Apparatus for Cleaning the volatile organic compounds in the painting process - Google Patents

Abstract

The present invention relates to an apparatus for removing harmful gases in a painting process, and more particularly, to intermittently perform adsorption and desorption so as to maintain an equal load in a plurality of adsorption towers of volatile organic compounds generated in a painting operation, and at a high temperature discharge gas during desorption. The present invention relates to an apparatus for removing volatile organic compounds in a coating process to improve the adsorption efficiency and the energy utilization efficiency by reusing heat.

In the present invention described above, in the volatile organic compound removal device of the coating process, the adsorption and desorption unit is configured in parallel with the adsorption tower, and the flow rate of the gas flowing into the adsorption tower of the adsorption and desorption unit is kept constant to improve the adsorption efficiency. Desorption is performed by introducing heated air into the adsorption-and-desorption unit in a stopped state, and a high temperature discharged from the catalytic combustion reactor after the exhaust air containing the desorbed volatile organic compound is heated by a burner and then completely burned by the catalytic combustion reactor. By recycling the air necessary for desorption by introducing air back into the adsorption and desorption unit, the efficiency of removing volatile organic compounds in the coating process is remarkably improved, and the cost for removing volatile organic compounds in the coating process is reduced. to provide.

Painting process, automobile coating, adsorption tower, adsorption and desorption, catalytic combustion reactor, volatile organic compound

Description

Apparatus for Cleaning the volatile organic compounds in the painting process}

1 is a view showing a volatile organic compound removal device of the automotive painting process according to an embodiment of the present invention.

Figures 2a and 2b is a view showing the up / down flow upright cylindrical adsorption tower and the upright concentric cylindrical adsorption tower according to the present invention.

3 shows a gas burner for raising the concentration of the VOC.

4 shows a catalytic combustion reactor.

5A is a view showing a pipe divided into three branch pipes in six intermediate towers and two intermediate pipes.

5B is a view showing piping divided into two branch pipes each of six adsorption towers and three intermediate pipes.

FIG. 6 is a view showing piping divided into nine branching towers into three intermediate pipes and three branch pipes. FIG.

FIG. 7 is a view showing pipes in which 16 adsorption towers are divided into four branch pipes and four branch pipes.

8 is a view showing a pipe in which three adsorption towers are directly connected to three intermediate pipes.

9 is a view showing a pipe in which two adsorption towers are directly connected to two intermediate pipes.

10 shows a catalytic combustion reactor for incineration of volatile organic compounds by direct catalyst without an adsorption tower.

11 is a view showing the adsorption characteristics for the volatile organic compounds in the car painting booth when the flow rate of the granular activated carbon adsorption tower is adjusted and not.

12 is a diagram showing catalytic oxidation characteristics with respect to volatile solvent temperatures of a platinum catalyst.

FIG. 13 is a graph showing desorption characteristics during desorption and regeneration of the adsorption tower under uniform flow rate control, and catalytic incineration characteristics of the desorption concentrated volatile organic compounds.

Explanation of symbols on the main parts of the drawings

1: filter

10A, 10B, 11, 20A, 20B, 20C, 20D: Solenoid Valve

21A, 21B, 21C, 21D, 31A, 31B, 31C, 31D: Damper

22A, 22B, 22C, 22D, 32A, 32B, 32C, 32D: Sample Collection

40: adsorption tower

41: microporous throttle

42: adsorbent

45: flow distribution plate

50: gas exhaust blower

60: gas burner 61: flame stabilizer

62: Pilot Burner 63: Fuel Spray Nozzle

64: Ignitor 65: Flame Detector

66: swirl mixer

70: catalytic combustion reactor 71: catalytic combustion reactor inlet temperature sensor

72: temperature sensor 75: throttle

76: catalyst 77: insulation

80: concentrated VOC heating heat exchanger (desorption gas heat exchanger)

81: Inlet temperature sensor on VOC side of concentrated VOC heating heat exchanger

82: VOC side outlet temperature sensor of concentrated VOC heating heat exchanger

90: heat exchanger for air heating

91: inlet temperature sensor of the air heat exchanger

92: outlet temperature sensor of the heat exchanger for air heating

100: blower for removable air

111: desorption heat exchanger inlet valve 112: desorption air inlet emergency valve

120: electric heater

121: electric heater inlet temperature sensor

122: electric heater outlet temperature sensor

130: gas circulation blower 131: gas circulation valve

200: wall discharge type catalyst incinerator 201: suction induction pipe

202: liquid dust removal filter 203: wall exhaust blower

204: gas flow control filter 205: snail-type nichrome wire

206: metal honeycomb catalyst body 207: discharge induction pipe

The present invention relates to an apparatus for removing harmful gases in a painting process, and more particularly, to intermittently perform adsorption and desorption so as to maintain an equal load in a plurality of adsorption towers of volatile organic compounds generated in a painting operation, and at a high temperature discharge gas during desorption. The present invention relates to an apparatus for removing volatile organic compounds in a coating process to improve the adsorption efficiency and the energy utilization efficiency by reusing heat.

VOCs (Volatile Organic Compounds), which are mostly composed of hydrocarbons (HCs), are harmful to the human body but are flammable and explosive. However, in most solvent handling workplaces, VOCs are lean and are emitted in large quantities, so it is common to dispose of them under environmental regulations rather than recovering and reusing them.

Incineration is carried out in the most common manner, in which:

HC + O2 → H2O + CO2

However, VOCs are not burned directly because they are emitted at low concentrations, and they are explosive and do not burn directly, even if they are emitted at concentrations that can burn. Therefore, thermal combustion, which raises the temperature of the lean gas and reacts with heat, is generally performed and reacts as follows.

Thermal

HC + O2 → H2O + CO2

1400-1800 ℉

However, in order to perform thermal combustion as described above, high temperature maintenance, high heat loss due to heat dissipation after combustion, and high heat exchange cost are used, and thus, many catalytic combustion methods are adopted (Catalytic Control of VOC Emissions, MECA (Manufactures) of Emission Controls Association, 1992). The reaction scheme by catalytic combustion is as follows.

Catalyst

HC + O2 → H2O + CO2

500-900 ℉

The above-mentioned combustion reactions used a method of increasing the temperature of the reaction gas by introducing a heat exchanger as a method of recovering combustion heat by an exothermic reaction, but in recent years, the facility cost is high, but the method of reducing the operating cost is regenerative thermal oxidation (RTO) of a regenerative heat exchange method. B or RCO (Regenerative Catalytic Oxidation) has been developed and used.

However, these methods require limited heat storage for their reactions, and their operation is low and their use is limited in the workplace where VOC occurs intermittently. In addition, the RTO RCO has a huge device, making it difficult to install in a small workplace due to the limitation of the installation space. Therefore, in the small-scale small workplace, the method of continuously adsorption-concentrating the VOC and then periodically desorbing and regenerating the incineration is used. At this time, the adsorption process is exothermic and in the desorption process, it is necessary to control the conditions for each of the opposite processes. As an example, the adsorption conditions of activated carbon to VOC in the painting process, the contact time is more than 2 seconds, the linear velocity is about 0.2 ~ 0.4m / sec (possible heat storage under 0.2m / sec), the inlet temperature is below 70 ℃ (adsorption tower Internal temperature below 50 ℃) should be maintained. Desorption conditions for this are more complicated. The breakthrough point of activated carbon is about 70 ° C., and when desorption of high concentration is concerned, it is recommended to desorb with inert gas or water vapor because of the explosion reaction. Therefore, rapid desorption or high concentration emissions should be avoided when desorption by air. The US Manufacturers of Emission Controls Association (MECA) recommends that VOC incineration be operated at or below 25% Lower Explosion Limit (LEL).

Republic of Korea Utility Model 20-0228794 relates to the exhaust gas purification device of the paint booth of the automobile, there is no regeneration system because it is concentrated on the filter of dust removal, especially the filter at this time maintains the uniformity of intake.

As for the regeneration device, the Republic of Korea Patent No. 10-0426677 discloses that the problem in the prior art is disclosed, but the invention of the Republic of Korea Patent No. 10-0426677 is configured such that both the gas desorption and the temperature rise of the catalyst incineration are made by an electric heater. There is a problem that excessive energy consumption during regeneration.

Republic of Korea Patent 10-0492070 is to heat the air with a burner or electric heater to desorb the activated carbon, characterized by the use of a sprinkler to prevent overheating.

Korean Patent Laid-Open Publication No. 10-2005-0017167 discloses that a plurality of pyramid-shaped adsorption tubes are arranged for uniform adsorption and desorption, but in general, the desorption uses less than the flow rate during adsorption. Flow control is difficult. In addition, the desorption is difficult during the adsorption operation, and the intermittent operation is possible, but there are problems in that the facility cost and the operation cost are excessively generated because there are two catalytic combustion reactors installed for the combustor and NOx or SOx removal and there is no heat recovery facility.

In Korean Patent Laid-Open Publication No. 10-2003-009230, desorption of a concentrated gas adsorbed in an adsorption tower in a drying process for 30 to 50 minutes in an automobile coating booth, followed by catalytic combustion to be used as a coating drying hot air heat source or recovering heat with a heat exchanger. Is disclosed. However, desorption is difficult to be achieved within a short time, and residual heat remains after desorption, and the adsorption efficiency is greatly reduced for a considerable time after desorption, or when activated carbon is directly used as a desorption heat source at a temperature of 400 to 500 ° C. There is a risk of burnout. In addition, the Republic of Korea Utility Model 20-0284130 process is the same or similar to the Republic of Korea Patent Publication No. 10-2003-009230, but desorption by inserting the desorption communication into the activated carbon adsorption cylinder respectively, the desorption operation after desorption is also a problem that requires a considerable time Has

U.S. Patent 5,814,132 discloses intermittent regeneration of adsorbed VOCs, heating with a burner, incineration of the catalyst, and re-use as a heat source for the coating booth. At this time, adsorbents are recommended, such as zeolite or activated carbon.

In US Pat. No. 6,051,199, a VOC removal method in a solvent handling process constitutes a adsorption / desorption tower having a TSA (Temperature Swing Adsorption) concept in which a rotary cylinder adsorption / desorption zone is divided, and an incineration treatment is performed immediately by a catalyst at the desorption outlet. However, in Japanese Patent Application Laid-Open No. 2004-130189, it is possible to direct fire by concentrated desorption at a high concentration in a TSA system, but there is a problem that an explosion of VOC may occur.

U.S. Patent 6,576,198 B2 has a two-chamber structure which can perform adsorption and desorption at the same time and replace the operation by damper operation. Desorption is disclosed.

Japanese Patent Laid-Open No. 8-110018 discloses the use of a pyramid plate and a multi-layered porous plate thereon in order to equalize the flow of gas flowing into an RTO or RCO system or a regenerative oxidation tank.

In Japanese Patent Laid-Open Publication No. 2005-177650 and Japanese Patent Laid-Open Publication No. 2004-8987, desorption of activated carbon or zeolite adsorbent at a high temperature of 100-800 ° C. with oxygen concentration of less than 8% at the time of desorption is performed. It features. However, there is a problem in flame stability because the US MECA recommends less than 10% of oxygen concentration below 50% LEL.

Japanese Patent Application Laid-Open No. 2004-125329 discloses the use of a chemical heat pump for adsorption / desorption heat operation as a system for condensing the incoming VOCs and vaporizing the catalyst intermittently.

Japanese Laid-Open Patent Publication No. 2005-152701 discloses a two-stage catalyst layer structure in which the catalyst layer is operated at initial cold start without reaching a sufficient temperature for initiating the catalysis, so that the complete oxidation reaction is completed. .

However, the above-described prior arts are mostly configured to perform continuous processing, and are difficult to apply for intermittent processing. In particular, when the installation space is insufficient, the drift flow is severe in the piping or during normal operation in the initial cold start. Operation and heat dissipation loss to reach, such as efficiency or problems, such as the actual conditions of the field work and problems that occur in the operation has not been considered.

In addition, comprehensive consideration of the physical properties of the adsorbents and catalysts used or the arrangement and shape of the reactor is insufficient, resulting in a problem of not only a second environmental pollution but also a safe operation.

Accordingly, the present invention is to solve the above-mentioned problems in the prior art, the gas flow for each adsorption tower in a plurality of adsorption towers connected in parallel to the volatile organic compounds (VOC) generated at a low concentration in the coating process Adsorption is carried out efficiently by equalizing and uniformly contacting the adsorbent.In the desorption process, the desorption and incineration are carried out by periodically desorbing the catalyst at a high concentration and recovering heat through a heat exchanger and reusing the recovered heat. It is an object of the present invention to provide an apparatus for removing volatile organic compounds in a coating process that performs intermittent adsorption and desorption to minimize the additional heat source required for the purpose.

The present invention for achieving the above object is an air inlet for supplying warm air; After the inlet gas or the heated air flowing from the paint booth is uniformly introduced, adsorption and desorption is performed, and when the adsorption is carried out, the exhaust gas is discharged to the outside and the desorption gas is discharged to the catalytic reaction unit when the desorption is formed as a parallel adsorption tower Adsorption-desorption part; A catalytic reaction unit connected by a pipe having an opening and closing opening to receive gas for desorption gas discharged from the adsorption and desorption unit during desorption and catalyzing the desorption gas and then introducing a high temperature discharge gas into the air inlet; Characterized in that comprises a.

The adsorption-and-desorption unit has an opening for opening and blocking the inflow and inflow of the inlet gas flowing through the filter from the paint booth, and the inlet main pipe portion to which the pipe to which the warm air flows is introduced; An inlet intermediate pipe part having an inflow amount adjusting opening configured to equally divide the gas introduced from the inlet main pipe part to be introduced into the adsorption tower part; An adsorption tower unit including an adsorption tower set formed by at least one adsorption tower respectively connected to a gas outlet of the inlet intermediate pipe part in parallel; Outlet intermediate pipe parts connected to the outlets of the adsorption tower, respectively, for joining the outflow gases of the adsorption tower; And an outlet main pipe part having an opening and closing port which is opened to be discharged to the outside when the gas joined from the outlet intermediate pipe part is adsorbed and is closed to be introduced into the catalytic reaction part when being desorbed.

The inlet intermediate pipe part may include at least one first branch pipe branched from the inlet main pipe part; At least one second branch pipe connected to each of the first branch pipes by branching so that a gas flows into each of the adsorption towers forming the collection tower; It is characterized in that it comprises a gas inlet regulator is attached to each of the second branch pipes to equally regulate the flow of gas in each of the second branch pipes.

The adsorption tower unit, the adsorption tower is connected to each of the second branch pipe, the adsorption tower connected to the second branch pipe connected to the first branch pipe forms an adsorption tower set, the adsorption tower set is the first branch pipe It is characterized in that it is configured in parallel with the same number.

The outlet intermediate pipe portion, at least one third branch pipe connected to the outlet of the adsorption tower portion, each having an opening and closing port; And the same number of concentrator tubes as the first branch tube in which the third branch tubes connected to the adsorption tower unit constituting the adsorption tower assembly are concentrated.

The opening and closing port is characterized in that the solenoid valve (Solenoid valve).

The gas flow rate control port is characterized in that configured by arranging at least one damper in series. In addition, the flow rate control port may be configured to include a sampling port for installing and measuring a Pitt tube (Pitot Tube) flowmeter or a hydrostatic pressure meter in addition to the damper arranged in series.

The adsorption tower may include a fine porous control plate provided at an inner side to which the second branch pipe is coupled to adjust the drift of the introduced gas into parallel flow; Characterized in that it comprises a; activated carbon adsorbent is filled in the next position of the fine porous control plate.

The adsorption tower may further include a microporous throttle plate having an upright cylindrical shape in which the gas flows from the bottom to the top, and adjusting the drift of the gas introduced in the inlet of the gas into parallel flow; A flow distributor disposed inside the upright cylinder and having at least one flow distribution plate for uniformly passing gas through the inner cylindrical wall; Characterized in that it comprises a; activated carbon adsorbent stacked in a cylindrical shape on the inner wall side of the adsorption tower.

Here, the height of the upright cylindrical adsorption tower is less than three times the diameter of the inner cylinder (Di) of the upright cylinder, the flow distributor is provided with three flow distribution plates, the lowest flow distribution plate of the flow distribution plate has a diameter The 1 / 4Di to 1 / 2Di so as to be positioned at the position of the microporous throttling plate, and the second flow distribution plate is located at a position of 1Di from the bottom of the adsorption tower to have a diameter of 1 / 3Di to 2 / 3Di, The third flow distribution plate is characterized in that the diameter is 1 / 3Di to 3 / 4Di so as to be positioned at a position 2Di from the lower portion of the adsorption tower.

The activated carbon adsorbent is characterized by comprising a stack of activated carbon such that the residence time is 0.2 seconds or more at a linear velocity of 0.2 to 0.4 m / sec.

The air inlet unit, a blower for air inlet; An air heating heat exchanger for heating the inlet air of the blower by using the exhaust gas of the catalytic reaction unit; And an electric heater that warms the warm air introduced into the adsorption-and-desorption unit in the initial stage of the desorption in the air heating heat exchanger.

The catalytic reaction unit may include: a desorption gas heat exchanger having a separate gas path for discharging the gas flowing out of the adsorption and desorption unit to a burner and discharging the gas introduced from the catalytic combustion reactor to the air inlet unit; A burner for heating the desorption gas introduced from the desorption gas heat exchanger; It characterized in that it comprises a catalytic combustion reactor for introducing a hot exhaust gas into the desorption gas heat exchanger after the catalytic reaction to remove the volatile organic compounds of the desorption gas heated in the burner.

The catalytic combustion reactor may include: a gas flow control plate configured to have parallel flow of the gas introduced into the inlet of the catalytic combustion reactor; And a catalyst comprising a catalyst active material supported on a catalyst support having a high thermal conductivity embedded in a position next to the gas flow control plate.

The catalyst is characterized in that the catalytically active material of any one of platinum or gamma-alumina is formed by a washcoat (Washcoat) on the metal honeycomb catalyst support to improve the thermal conductivity of the catalyst support.

The burner may include: a flame stability protection passage for stabilizing a heating flame of the gas introduced from the desorption gas heat exchanger; An igniter for gas-fired ignition in the flame stabilizer; A flame detection tube formed on one side of the flame stability protection tube; A pilot burner provided at a rear end of the flame stabilization protection box, the flame being turned on and off to maintain the inlet temperature of the catalytic combustion reactor; And a gas spray nozzle group formed outside the pilot burner to form a stable flame.

The burner may also be configured to further comprise a swirl mixer provided at the outlet of the flame stabilizer.

The first branch pipe and the second branch pipe is formed with a sampling port for collecting the inlet gas. In addition, the concentrator tube is formed with a gas inlet opening and closing port for controlling the outflow of the gas, and a sampling port for comfortably collecting the outflow gas.

The present invention described above operates by adjusting the diameter and height of the adsorption tower equipped with granules of activated carbon or zeolite or the adsorbent of honeycomb and the number of adsorption towers so as to maintain an appropriate linear velocity and space velocity in accordance with the adsorption characteristics of volatile organic compounds.

The air supplied to the adsorption and desorption unit by the air inlet unit for desorption of the volatile organic compound adsorbed on the adsorbent is performed by heat of the electric heater at the initial stage of desorption, but the desorption proceeds and the air is heated at a predetermined temperature or more. The steady state is sufficiently performed by heat exchange using combustion waste heat, and the waste heat is also used to raise the temperature of the concentrated desorption gas containing volatile organic compounds desorbed from the adsorption and desorption unit. At this time, if the concentrated concentrated desorbed gas is insufficient to maintain the catalytic reaction, a burner (gas burner) is operated to maintain the complete catalytic reaction by heating the desorbed gas. The burner is controlled by on / off operation of gas fuel supply without external air supply.

Intermittently adsorbed volatile organic compounds are concentrated and stored in an adsorption tower and periodically desorbed by blowing hot air. At this time, the operation period is determined so that the desorbed gas concentration is less than 25% of the lower explosion limit. In addition, the air heating temperature for desorption is also controlled according to the characteristics of the adsorbent, and the catalyst layer is controlled so as not to overheat. If the heat exchanger does not reach a steady state and the desorption air is low or the heat exchanged desorption air is overheated, the exhaust gas is partially recycled and mixed with the bypass air to be used as the desorption air. It is desirable to keep as much as possible.

Preferably, when the catalytic combustion reactor outlet temperature is over 600 ° C., the opening and closing port of the solenoid valve, etc., formed in the pipe flowing into the air heating heat exchanger is closed, and the opening and closing opening made of the bypass solenoid valve of the desorption air blower is opened. In addition, the electric heater and the fuel supply to the burner are cut off so that the temperature of the catalytic combustion reactor exits below 600 ° C.

Another configuration of the volatile organic compound removal device of the coating process of the present invention for achieving the above object is a filter for removing the droplets and dust of the gas; A blower for flowing the gas; A gas flow filter for making the gas flow uniform; It is characterized in that it comprises a; and a catalytic reactor for discharging after the catalytic reaction after heating the gas.

The apparatus for removing volatile organic compounds in the coating process may further include: a suction induction pipe configured at the front end of the filter part to induce the inflow of a gas containing volatile organic compounds spread in the workplace; And a discharge induction pipe configured at an outlet of the catalytic reactor to induce the outflow of the processing gas discharged from the catalytic reactor.

The catalytic reactor may include an electric heater for heating the gas; It characterized in that it comprises a metal catalyst body for the catalytic combustion reaction of the heated gas.

The catalytic reactor may further include an electrically heated catalytic converter (EHC) in which an electric heater and a metal catalyst body are integrally formed.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 is a view showing a volatile organic compound removal device of the automotive painting process according to an embodiment of the present invention.

As shown in FIG. 1, an apparatus for removing volatile organic compounds according to an embodiment of the present invention includes an air inlet unit 90, 100, 111, 112, 130, 120, 121, 122, and the like that supplies air for adsorption and desorption. Inclusive); A filter (1) for removing dust and droplets of harmful gases emitted from a vehicle paint booth as a source of volatile organic compounds (VOC); A main pipe duct (inlet main pipe part) to induce gas flow and a solenoid valve 10A or dampers 21A and 21C for blocking gas flow in the main pipe; Regulating dampers (21A, 21C) and Pitot tube flowmeters or hydrostatic pressure gauges for evenly controlling gas flow shutoff solenoid valves (20A, 20C) and flow from the main piping to the intermediate piping (first branch pipe). Sampling outlets (22A, 22C) that can be installed and measured; Control dampers 31A, 31B, 31C, 31D that can control gas flow evenly from the intermediate pipe to the branch pipe (second branch pipe), and sampling ports 31A, 32B, 32C, 32D for flow measurement Adsorption and desorption part comprising a branch pipe (second branch pipe) to guide gas to the adsorption tower (40: 40A, 40B, 40C, 40D); It includes a catalytic reaction unit (including 60, 70, 80, etc.) for receiving the desorption gas discharged from the adsorption and desorption unit and then catalyzed the reaction and the heated hot air into the air inlet.

At the outlets of the adsorption towers 40: 40A, 40B, 40C, 40D, at least one third branch pipe is connected to each of the adsorption towers, and is connected to the adsorption tower unit constituting the adsorption tower assembly 40A and 40B or 40C and 40D. Solenoid valves 20B and 20D each having the same number as the first branch pipes in which the third branch pipes are concentrated are provided as opening / closing holes to form a concentrating pipe which collects and discharges the exhaust gas of the first branch pipe. Here, the pipe section consisting of the third branch pipes and the concentrating pipes forms the outlet intermediate pipe of the present invention.

The concentrator pipe is intensively coupled to one outlet main pipe portion in which the solenoid valve 10B as the opening and closing port for opening and closing the outflow of gas is concentrated so that the gas is joined at the outlet main pipe portion.

The outlet main pipe part includes a gas burner 60, a catalytic combustion reactor 70, and a volatile desorbed from the adsorption tower by a concentrated VOC heating heat exchanger 80 among the catalytic reaction sections including a concentrated VOC heating heat exchanger 80. A pipe provided with a solenoid valve 11 for introducing a gas (desorption gas) containing an organic compound is connected.

In addition, the inlet main pipe part has an air inlet blower 100, an air heating heat exchanger 90 for supplying heated air for desorption of volatile organic compounds adsorbed by the adsorption tower during desorption, and desorption in an initial process of desorption. Air inlet is composed of an electric heater 120 for heating the air to be introduced for the adsorption or desorption is required by the pipe so that the air required for adsorption or desorption flows into the adsorption tower of the adsorption-desorption unit through the inlet main pipe.

Figures 2a and 2b is a view showing the up / down flow upright cylindrical adsorption tower and the upright concentric cylindrical adsorption tower according to the present invention.

2A shows a flow upright cylindrical adsorption tower, the flow rate is uniformly adjusted in the branch pipe (second branch pipe) to control the flow of the target gas reaching the inlet of the adsorption tower 40 in parallel flow. A microporous throttle plate 41 may be formed at the gas inlet side of the adsorption tower 40, and the activated carbon adsorbent may be filled in a stack to configure the adsorption tower 40. Here, the stacking of the activated carbon adsorbent filled in the adsorption column is preferably configured to have a residence time of 0.2 seconds or more at a linear speed of 0.2 to 0.4 m / sec.

2B shows an upright concentric cylindrical adsorption tower, as shown, an adsorption tower is formed in an upright concentric cylinder such that gas flows from the bottom up, and the height of the adsorption tower 40 is within three times the inner cylinder diameter Di, and the inner cylinder. A flow splitter consisting of flow splitters is installed in the center of the inner cylinder so that the gas passes evenly through the wall. At this time, the first flow distribution plate at the bottom is installed at the same position as the lower part of the adsorption tower after the fine porous control plate, and the diameter is 1 / 4Di to 1 / 2Di, and the second flow distribution plate is 1 / 3Di in diameter at the position 1Di from the lower part of the adsorption tower. It is preferably installed to 2 / 3Di, and the third flow distribution plate is preferably installed to have a diameter of 1 / 3Di to 3 / 4Di at a position of 2Di from a lower portion of the adsorption tower, but is not limited thereto.

Referring back to FIG. 1, the gas exiting the adsorption tower 40 joins in the downstream intermediate pipe (concentrator pipe) through the downstream branch pipe (third branch pipe), and the solenoid in the downstream intermediate pipe (concentrator pipe). The valves 20B and 20D and the sampling ports 22B and 22D are installed, and the gas, which is joined between the downstream intermediate pipes (concentration pipes), joins the outlet main pipes forming the downstream outlet main pipes and exits the main pipe line. It is configured to be discharged to the atmosphere through the nose valve (10B) or the damper and then the discharge blower (50). On the other hand, the pipe provided with the solenoid valve 11 is provided between the downstream intermediate pipe (concentration pipe) and the downstream main pipe (outlet main pipe part) so that desorption gas can flow into a catalytic reaction part (refer FIG. 1).

The desorption process operation should be carried out periodically in the range of 30% to 100% of the adsorbent adsorption capacity, but should be cooled to 50 ° C or lower until the adsorption operation after the desorption is completed. In the case of heat regeneration by air, it is necessary to control the air inflow so that the maximum concentration of the desorption gas is within 25% of the average LEL, and the temperature of the heated air is recommended to be less than 110 ° C in the case of granular activated carbon.

Preferably, the desorption air inlet blower 100, the electric heater 120, and the air heating heat exchanger 90 are configured to satisfy the desorption conditions. In the initial stage of the desorption operation when the air heating heat exchanger 90 is not sufficiently heated, the solenoid valve 111 on the side of the air heating heat exchanger is locked and the solenoid valve 112 on the desorption air bypass side is opened to directly heat the air. Connection to the heat exchanger 90 side. In addition, when the air temperature for desorption through the air heating heat exchanger 90 rises by 120 ° C. or more, if the adsorbent is activated carbon, there is a risk of fire, and the solenoid valve 131 is operated while the gas circulation blower 130 is operated. The solenoid valve 111 of the air heat exchanger side is locked while opening the solenoid valve 112 for detachable air bypass.

Preferably, desorption air of 110 ° C. or less is introduced through the main pipe valve 10A, the solenoid valves 20A, 20C, ... for the intermediate pipe, and the intermediate desorption air inlet pipe, and sequentially enters the inlet. The solenoid valves 20A, 20C, ... constituting the intermediate pipe portion are introduced into the adsorption tower to perform desorption. For example, in FIG. 1, when 21A of the valves of the intermediate pipe is opened, the outlet 20B is opened, the valves of the remaining intermediate pipe are closed, and desorption work is performed in the adsorption towers 40A and 40B. The desorption air passing through the intermediate pipe reaches the adsorption tower evenly through the branch pipe to be 1/2 to 1 times the amount of the adsorption gas.In the case of granular activated carbon having a desorption diameter of 4 mm or more, the desorption time is 110 ° C. or less. Keep over time.

Preferably, the desorbed rich VOC gas discharged through the downstream branch pipe (third branch pipe) and the intermediate pipe (concentration pipe) is connected to the front end of the locked solenoid valve 10B formed at the outlet main pipe part. And the solenoid valve 11 is introduced into the concentrated VOC heating heat exchanger (desorption gas heat exchanger) (80).

Preferably, the concentrated VOC heating heat exchanger (desorption gas heat exchanger) 80 is a shell / tube type, and the high temperature combustion exhaust gas reacted through the catalytic combustion reactor 70 passes through the tube side. It is configured to be discharged to the air heating heat-heat exchanger 90 side for air heating, and to the heated gas burner 60 passes through the concentrated VOC gas to be heated to the shell (Shell) side.

Preferably, as shown in FIG. 3, since the concentrated VOC gas is warmed to a considerably high temperature in the concentrated VOC heating heat exchanger (desorbent gas heat exchanger) 80, further heating the desorbed gas heated in the gas burner 60. In order to reduce the amount of heat required in order to generally require a very small gas burner, the burner (gas burner) 60 is provided with a flame stability protective casing 61 to facilitate flame stability. In addition, fuel flow control of the gas burner 60 for maintaining the inlet temperature 71 of the catalytic combustion reactor 70 at 200 ° C to 400 ° C generally adopts an on / off operation for economic reasons. (62) A burner, eight gas atomizing nozzle groups 63 for stable flame formation, an igniter 64 for combustion ignition, a flame detection tube 65, and the like are configured in the flame stability protection tube 61. At this time, when the flame length is formed long or there is not enough space in the gas burner combustion chamber, the swirl mixer 66 is installed, and the swirl degree is installed in the outer casing of the flame stabilizer protection cylinder 61 so that the swirl degree is 0.1 to 1.0, and the gas burner outer wall and the catalytic combustion reactor ( Pipes up to 70 are to be insulated.

4 is a view showing a catalytic combustion reactor.

As shown in FIG. 4, the catalytic combustion reactor 70 is provided with a gas flow control plate 75 at the inlet side of the inner side such that the desorbed gas flowing from the gas burner 60 into the catalytic combustion reactor 70 becomes parallel flow. In the next position of the throttle plate 75, a catalyst 76 supporting a catalytically active material is formed on a metal or ceramic honeycomb-shaped catalyst support having high thermal conductivity, and the metal or ceramic honeycomb-shaped catalyst 76 is transferred to the outside. It is to be protected with a soft heat insulating material for the protection of heat insulation and damage to the catalyst, and the heat insulating material is configured to re-insulate the outside of the catalytic combustion reactor (70). In this case, platinum is preferred as the catalytically active material, but it is also effective to wash-coat gamma-alumina to a honeycomb support. In this case, as described above, the catalyst support is preferably made of a material having a high thermal conductivity as much as possible in order to increase the heating rate of the catalyst.

Preferably, when the outlet temperature 72 of the catalytic combustion reactor 70 is overheated to 600 ° C. or more, the solenoid valve 111 flowing into the air heating heat exchanger 90 is locked and the bypass solenoid of the desorption air blower is closed. Opening the nose valve 112 cuts off the supply of electricity and fuel to the gas burner 60 to the electric heater 120 so that the outlet temperature 72 of the catalytic combustion reactor 70 becomes 600 ° C. or less.

Desorption work is carried out by intermediate valves (by solenoid valves forming intermediate pipes of inlet and outlet). In the case of granular activated carbon, the desorption operation is to be maintained at 110 ° C for at least 2 hours. After the desorption work is completed in the adsorption tower during the desorption process, the temperature of the adsorption tower is naturally cooled to 50 ° C or lower and the adsorption work is resumed. That is, the adsorption-desorption work is intermittently performed.

Figure 5a is a view showing a pipe divided by six adsorption towers into two intermediate pipes each three branch pipes (three adsorption towers form one adsorption tower set, two adsorption tower sets are connected in parallel), Figure 5b 2 is a diagram showing a pipe dividing an adsorption tower into three intermediate pipes and two branch pipes (two adsorption towers form one adsorption tower set and three adsorption tower sets connected in parallel), and FIG. The diagram shows piping divided into three branch pipes in the pipe (three adsorption towers form one adsorption tower set, and three adsorption tower sets are connected in parallel), and FIG. 7 shows 16 adsorption towers in 4 intermediate pipes each. A diagram showing piping divided into two branch pipes (four adsorption towers constitute one adsorption tower set, and four adsorption tower sets are connected in parallel).

In order to efficiently perform the adsorption and desorption work, it is important to arrange the pipes so that the flow rate of air or gas flowing into each adsorption tower can be equally controlled. The intermediate pipes are divided into two and each branch pipe is divided into two branch pipes (hereinafter referred to as 2x2 arrays).

When six adsorption towers are required, there are 2x3 arrays as shown in FIG. 5A and 3x2 as shown in FIG. 5B. The 2x3 array can reduce the number of intermediate valves and adsorption towers compared to the 3x2 array system, but the capacity of the removable blower 100, the heat exchanger and the heating equipment is relatively large, and the desorption operation must be frequently performed.

When 8 adsorption towers are installed, there are 2x4 and 4x2 arrangements for piping arrangements. Especially, in 2x4 arrangements, care should be taken to ensure that desorption gas is not discharged at once and that the concentration is within 25% LEL. In the case of installing nine adsorption towers, as shown in FIG. 6, the piping arrangement is made in a 3x3 arrangement, and in the case of the installation of 12 adsorption towers, the piping arrangement is possible in the arrangement of 3x4 or 4x3. As shown in the figure, the pipe arrangement is configured in a 4x4 arrangement.

FIG. 8 is a view showing a pipe in which three adsorption towers are directly connected to three intermediate pipes, and FIG. 9 is a view showing a pipe in which two adsorption towers are directly connected to two intermediate pipes.

When the adsorption and desorption part of the volatile organic compound removal device is smaller and needs two or three adsorption towers, as shown in FIGS. 8 and 9, the main pipe, the intermediate pipe, and one adsorption tower assembly are formed without a branch pipe. It may be composed of a adsorption-desorption chamber of the yarn. At this time, the valve of the main pipe is provided with a manual damper or valve.

FIG. 10 is a view illustrating a volatile organic compound removing device of a coating process of catalytically burning a volatile organic compound without an adsorption tower as another configuration of the present invention.

It is more efficient to incinerate incineration without adsorption and desorption because of the small work site. In this case, a window type catalyst incinerator 200 as shown in FIG. 10 is installed. Window type catalyst incinerator 200 is to be installed easily between the wall and the outside without the installation of a thermal insulation material, suction induction pipe 201, droplets and dust to induce to discharge the VOC spread in the workplace outside To filter the filter 202, the wall discharge blower 203, the outer wall of the catalyst body, and the gas flow filter 204 to uniformly uniform the gas flow in heating the inlet gas. It consists of a snail type electric heater 205 for heating so that the reaction is possible, a metal honeycomb catalyst body 206 having a rapid heat rise and excellent impact resistance, and an exhaust induction pipe 207 for discharging the treated gas to the outside. It is also possible to replace the electric heater with an electrically heated catalytic converter (ECH) using a snail-type electric heater and a metal catalyst as one. In addition, it is preferable that the catalyst support of the catalyst body 206 is also made of a material having the highest thermal conductivity as possible for rapid heating of the catalytically active material.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1

11 is a view showing the adsorption characteristics for the volatile organic compounds in the car paint booth when the flow rate of the granular activated carbon adsorption tower is adjusted or not.

VOC adsorption characteristics test of activated carbon during car painting work in car paint booth with 9x activated carbon adsorption column in pipe arrangement with uniformly adjusted flow of branch pipe and adsorption tower (indicated after adjustment) Contrast experiments (marked before adjustment) were sampled from the main pipe before and after adsorption and analyzed as shown in FIG. 11. If the gas flow was not adjusted for the same flow condition, the gas flow was not uniform for each branch pipe, and because of the flow, the contact of the adsorption tower layer was not uniform. Compared with the gas flow uniformly, there is a significant delay on the inhomogeneous inflow VOC, and more than 90% of the gas is adsorbed and purified.

Example 2

FIG. 12 is a diagram showing catalytic oxidation characteristics with respect to volatile solvent temperatures of a used platinum catalyst. FIG.

The catalyst used was washcoated with 0.12% of gamma alumina on a plcalloy metal honeycomb support, sintered at 450 ° C. for about 1 hour, and then calcined at 500 ° C. for 1 hour after supporting about 1% platinum of gamma alumina. Again, activated for about 30 minutes at 400 ℃ hydrogen reduction atmosphere was used.

The test subjects were selected from Xylene, MIBK, Cyclohexane, Ethyl acetate and Iso-propyl alcohol among the organic solvents used in the painting process. A change in conversion rate with respect to temperature is set at about 1000 ppm, as shown in FIG. 12.

As shown in FIG. 12, most solvents showed a conversion rate of 90% or more at about 250 ° C., but a slightly lower conversion rate was found in cyclohexane, but more than 98% of conversions were performed at 300 ° C. or more.

Example 3

FIG. 13 is a diagram showing the desorption characteristics during desorption and regeneration of the adsorption tower controlled by the flow rate uniformity, and the catalytic incineration characteristics of the desorption concentrated volatile organic compounds.

Desorption experiment results of the three adsorption towers in the activated carbon adsorption tower 9 pipe arrangement 3x3 arrangement method is shown in FIG. Activated carbon desorption control set temperature was 110 degreeC, and catalyst inlet control set temperature was performed at 250 degreeC. The average 25% LEL of the paint used is about 3300 ppm.

The desorption of activated carbon actually started to occur before 70 ° C, and it was active at over 80 ° C. The desorption of activated carbon occurred at the maximum concentration at the desorption control temperature of 110 ° C.

At the catalyst incineration control temperature below 250 ℃, less than 5% of unreacted water was discharged due to the low influent concentration. However, VOC desorption was very strong, and the complete conversion of VOC was more than 99.5% at the catalyst outlet temperature of 280 ℃. .

Example 4

When the VOC desorption concentration was 1000 ppm or more, the concentrated VOC passed through the heat exchanger 80 to maintain the gas burner inlet temperature of about 200 to 260 ° C., and the air heater inlet temperature was 110 to 110 ° C through the air heating heat exchanger 90. The result was 170 ° C. The results of this experiment show that the design of the two heat exchangers can be operated with only the desorption VOC without the supply of external electricity or gas fuel when the VOC desorption concentration is more than 1000ppm.

The present invention described above can safely manage the discharge of volatile organic compounds generated when discontinuously and irregularly working like an automobile paint booth under environmental regulations, and at the same time, greatly reducing facility and operating costs by minimizing additional energy required in regenerating adsorbents. It provides an effect that can be done.

In addition, the present invention provides an effect of reducing the energy consumption by more than 80% compared to the conventional electric heater treatment system by introducing a heat exchange gas combustion preheating technology in the treatment of flammable VOC.

In addition, the present invention can be expected to replace the import and export effect by providing a unique ultra-small gas burner design technology for heating up the concentrated VOC.

In addition, the present invention is a maximum of 400ppm total THC (Total Hydro-Carbon) is generated in the automotive paint booth, the discharge of about 140ppm in the conventional treatment facility up to 40ppm by piping control and proper operation to the ideal gas flow and treatment It provides the effect of being able to suppress below.

In addition, the present invention provides an effect to achieve a clean treatment technology by periodically processing the VOC that occurs irregularly and discontinuously so as not to interfere with the operation.

That is, the present invention can cleanly improve the working environment than the conventional coating process VOC treatment system to solve civil complaints due to odor emission, it is also possible to achieve cost reduction.

Claims (18)

In the apparatus for removing harmful gases discharged after performing a catalytic reaction to the desorption gas discharged from the adsorption-desorption unit for the adsorption-desorption of the harmful gas, the adsorption-desorption unit, An inlet main pipe portion having an opening for opening and blocking inflow of inflow gas introduced through a filter from the paint booth and connected to a pipe through which warm air is introduced; An inlet intermediate pipe portion which is composed of at least two branch pipes branched from the inlet main pipe portion and connected to the respective adsorption towers, and each branch pipe is provided with an inflow amount adjusting hole for uniformly controlling the gas flowing into the adsorption tower; ; An adsorption tower unit including an adsorption tower set formed by at least one adsorption tower respectively connected to a gas outlet of the inlet intermediate pipe part in parallel; Outlet intermediate pipe parts connected to the outlets of the adsorption tower, respectively, for joining the outflow gases of the adsorption tower; An outlet main pipe portion having an opening and closing opening to be discharged to the outside upon adsorption of the gas joined from the outlet intermediate pipe portion and to be introduced into the catalytic reaction portion upon desorption; Volatile Organic Compound Removal Device. delete An air inlet for supplying air; An inlet main pipe portion having an opening for inflow and inflow blocking of inflow gas introduced through a filter from the paint booth and connected to a pipe into which the warm air is introduced, and branched from the inlet main pipe portion An inlet intermediate pipe portion including at least two branch pipes connected to each adsorption tower, and each of the branch pipes is provided with an inflow adjustment port for uniformly controlling the gas flowing into the adsorption tower; An adsorption tower portion comprising at least one adsorption tower each connected to the adsorption tower set in parallel, an outlet intermediate pipe portion connected to an outlet of the adsorption tower portion to join the outflow gas of each adsorption tower, and the outlet intermediate piping portion When adsorbed gas is absorbed from the gas, it is opened to be discharged to the outside and when it is desorbed And an outlet main pipe portion having a closing opening and closing portion; It is connected by a pipe having a opening and closing opening so as to receive the desorption gas discharged from the adsorption-and-desorption unit during desorption catalytic reaction unit for the desorption gas and the high temperature exhaust gas into the air inlet; includes; Volatile organic compound removal device of the coating device, characterized in that the configuration. The inlet intermediate pipe part according to any one of claims 1 to 3, At least one first branch pipe branched from the inlet main pipe portion; At least one second branch pipe connected to each of the first branch pipes by branching so that a gas flows into each of the adsorption towers forming the collection tower; And a gas inflow regulator attached to each of the second branch tubes to uniformly regulate the flow of gas in each of the second branch tubes. The method of claim 3, wherein the adsorption column, An adsorption tower is connected to each of the second branch pipes, and adsorption towers connected to the second branch pipe connected to the first branch pipe form an adsorption tower set, and the adsorption tower set is equal to the number of the first branch pipes. The volatile organic compound removal device of the coating process, characterized in that configured in parallel. The method of claim 1, wherein the outlet intermediate pipe portion, At least one third branch pipe connected to an outlet of the adsorption tower, each having at least one opening and closing port; The apparatus for removing volatile organic compounds in a painting process comprising the same number of concentrating tubes as the first branch tube in which the third branch pipes connected to the adsorption tower part of the adsorption tower assembly are concentrated. The method according to claim 1, 3 or 5, wherein the adsorption column, A fine porous control plate provided inside the second branch pipe to which the second branch pipe is coupled to adjust the drift of the introduced gas into parallel flow; Activated carbon adsorbent is filled in the next position of the microporous control plate; Volatile organic compound removal apparatus of the coating process comprising a. The method according to claim 1, 3 or 5, wherein the adsorption column, The gas is an upright cylinder flowing from bottom to top, A fine porous control plate positioned at the inlet of the gas to adjust the flow of the gas to flow in parallel; A flow distributor disposed inside the upright cylinder and having at least one flow distribution plate for uniformly passing gas through the inner cylindrical wall; Volatile organic compound removal device of the coating process, characterized in that comprises ;; activated carbon adsorbent stacked in a cylindrical shape on the inner wall side of the adsorption tower. The method of claim 8, wherein the flow distributor, Three flow distribution plates are provided, and the lowest flow distribution plate is positioned at the position of the fine porous control plate so that the diameter is 1 / 4Di to 1 / 2Di, and the second flow distribution plate is 1 / diameter in diameter. 3Di to 2 / 3Di so as to be located at a position of 1Di from the bottom of the adsorption tower, and the third flow distribution plate is configured to be positioned at a position to be 2Di from the lower side of the adsorption tower to have a diameter of 1 / 3Di to 3 / 4Di. Volatile organic compound removal device of the coating process. The method of claim 3, wherein the air inlet, A blower for introducing air; An air heating heat exchanger for heating the inlet air of the blower by using the exhaust gas of the catalytic reaction unit; The volatile organic compound removing device of the coating process comprising a; electric heater for heating the warm air flowing into the adsorption-desorption unit in the desorption unit in the air heating heat exchanger. The method of claim 3, wherein the catalytic reaction unit, A desorption gas heat exchanger having a gas path separated to discharge the gas discharged from the adsorption and desorption part to a burner and introduce a gas introduced from a catalytic combustion reactor into the air inlet part; A burner for heating the desorption gas introduced from the desorption gas heat exchanger; And a catalytic combustion reactor for catalytically removing the volatile organic compound of the desorption gas heated by the burner and then discharging the hot exhaust gas to the desorption gas heat exchanger. The method of claim 11, wherein the catalytic combustion reactor, A gas flow control plate built in the inlet side of the catalytic combustion reactor so that the inlet gas is in parallel flow; The apparatus for removing volatile organic compounds in a painting process, comprising a catalyst comprising a catalyst active material supported on a catalyst support provided at a position next to the gas flow control plate. The method of claim 12, wherein the catalyst, An apparatus for removing volatile organic compounds in a painting process, wherein the catalytically active material of platinum or gamma-alumina is formed by a washcoat on a metal honeycomb catalyst support. The method of claim 11, wherein the burner, Flame stability protection passage for stabilizing the heating flame of the gas flowing from the desorption gas heat exchanger; An igniter for gas-fired ignition in the flame stabilizer; A flame detection tube formed on one side of the flame stability protection tube; A pilot burner provided at a rear end of the flame stabilization protection box, the flame being turned on and off to maintain the inlet temperature of the catalytic combustion reactor; Volatile organic compound removal device of the coating process, characterized in that it comprises a ;; the gas spray nozzle group formed on the outside of the pilot burner to form a stable flame. The method of claim 14, wherein the burner, Volatile organic compound removal device of the coating process, characterized in that further comprises a swirl mixer provided in the outlet of the flame stability protective cylinder. delete delete delete

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