KR20090079433A - Method of Treating and Purifying Organic Waste Gas Through Condensing-Absorbing Process and Advanced Catalytic Oxidation Process and Apparatus Therefor - Google Patents

Abstract

A highly efficient purification apparatus for treating organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process is provided to effectively treat the organic waste gas by reducing cost and time for maintaining the purification apparatus, and a method of treating and purifying the organic waste gas highly efficiently through the condensation-adsorption process and advanced catalytic oxidation process by using the apparatus is provided. A highly efficient purification apparatus for treating organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process comprises: a blower(10); first and second condensing-frost preventing units(30,31) connected to each other in series or parallel; an advanced oxidation unit(40); and a bypass duct(50). The first condensing-frost preventing unit includes a first condensing coil(301) and a first frost preventing unit(302). The second condensing-frost preventing unit includes a second condensing coil(311) and a second frost preventing unit(312). The advanced oxidation unit includes an ozone feeder(42) and a catalytic oxidation unit(41), or includes a non-thermal plasma electrode and the catalytic oxidation unit.

Description

Method of Treating and Purifying Organic Waste Gas Through Condensing-Absorbing Process and Advanced Catalytic Oxidation Process and Apparatus Therefor}

The present invention relates to a method and apparatus for treating and purifying organic waste gas, and more particularly, to a method and apparatus for treating and purifying organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process.

There is a stripping process that requires the use of strippers in the manufacturing process of the optical device industry that produces semiconductor wafers and TFT-LCD panels. The main components of the stripper have a high boiling point, and most of them are water soluble, including, for example, mono ethanol amine (MEA), dimethyl sulfoxide (DMSO), and ethylene glycolbutyl ether (BDG). Phosphorus is an organic compound.

Table 1 lists the major types of volatile organic compounds (VOCs) produced in the stripping process and the physical and chemical properties of the VOCs. Organic solvents having a low boiling point and high saturated vapor pressure are easy to volatilize but not easy to condense. On the other hand, VOCs having a high boiling point and low saturated vapor pressure are not easily volatilized, but are easily condensed. As shown in Table 1, acetone and isopropyl alcohol (IPA) are VOCs with low boiling point and high saturated vapor pressure when compared to other major solvent components, MEA, DMSO, and humidified 1-methyl-2- Pyrrolidinone (humidified 1-methyl-2-pyrrolidinone (NMP)) is VOCs with moderate to high boiling points and low saturated vapor pressures.

<Table 1>

The main types of VOCs produced in stripping processes in high tech industries and their physicochemical properties.

solvent Chemical formula Density (g / mL) Boiling Point (℃) receptivity Henry's Constant (mol / kg * bar) AALG ^[2] (g / m ³ ) Note ^[1] DMSO (CH ₃ ) ₂ SO 1.095 189.0 height More than 50000 - - MEA C ₂ H ₇ NO 1.014 171.1 height 6100000 25 * F, T BDG C ₈ H ₁₈ O ₃ 0.904 231.2 height - - F, T DMDS (CH ₃ ) ₂ S ₂ 1.057 109.9 lowness 0.91 - - DMS (CH ₃ ) ₂ S 0.850 38.0 lowness 0.48 - - Toluene C ₇ H ₈ 0.865 110.7 lowness 0.15 1420 F, T IPA (CH ₃ ) ₂ CHOH 0.783 82.4 Medium-low 88-170 19,600 F, T, C Acetone (CH ₃ ) ₂ CO 0.786 56.2 Medium-low 30 - -

Footnote [1]. F represents flammability and T represents a toxic or suspected carcinogen.

Footnote [2]. AALG stands for ambient air level goal. The source of AALG values in Table 1 is Lewis, Massachusetts, MA, 1991, by Calibrese, EJ, and Kenyon, EM, USA. Publisher, Inc., "Air toxics and risk assessment."

Among the components of the stripper described above, MEA is a polymer that tends to block adsorption pores which inversely affects the useful life of the adsorbent, and sulfur (S) deposited from DMSO is activated by zeolite catalysts to produce hot sparks. As such, DMSO will cause smoldering and will remain in the absorption holes on the zeolite rotary concentrator. In addition, because the substrates used in the high-tech industry have an increasingly expanding size, strippers used in the stripping process tend to volatilize through the outlets, so if proper work is not carried out, perhaps a serious ambient It causes air pollution.

Currently, condensers are mounted on the production floor by most high-tech manufacturers to regenerate and process VOCs produced during the manufacturing process. Such condensation regeneration systems have a high boiling point and most must be designed and operated correctly to achieve high regeneration efficiency of water soluble organic compounds. Using current condensation regeneration systems, VOCs regenerated through condensation can be purified for reuse. On the other hand, the concentration of VOCs, which has a high boiling point and is difficult to treat, is already greatly reduced after the condensation regeneration process, thus reducing the burden on subsequent waste gas treatment plants. As a result, thermally swinging online adsorption / desorption equipment can have extended life and effectively upgraded overall processing efficiency.

Common methods of controlling VOCs through condensation include cooling devices for cooling the VOCs waste gas to temperatures below the dew point temperature (eg saturation temperature) of the VOCs to achieve a saturated condensation effect. have. Book entitled "Estimating Costs of Air Pollution Control" by Betav. W. M. (Vatavuk, WM), incorporated herein by reference (Lewis Press, Chelsea) As described in Michigan, 1990, commonly used VOCs condensation systems include dehumidifiers and VOCs condensers. The dehumidifier removes excess moisture from the surrounding air, which occurs when the temperature of the condensation zone is below 0 ° C. (273K) and prevents the freezing-out effect, which is a disadvantage in the condensation process.

Study Induced by Zeiss and Ibbetson (1997, co-authored by RFZeiss and C. Ibbetson, Pollution Engineering 29 (9), pages 55-61, “Cryogenic Condensation on VOCs According to the section Cryogenic condensation puts a chill on VOCs, this reference will be incorporated into the present invention, the condensation performance in decreasing general VOCs is determined by the two most important factors. do. Firstly, the temperature of the condensation system must be sufficiently low (below -40 ° C), and secondly, the concentration of VOCs in the waste gas must be relatively high (above 10,000 ppmv). According to a study induced by Mr. Ganzevles (see Condensation for controlling VOC emission proposed by Ganzelves, FLA in November 2001, this reference is incorporated herein). In terms of the treatment of VOCs, the condensation performance tends to be inversely proportional to the linear speed of the waste gas. Therefore, the extended residence time of the waste gas in the condensation system helps to increase the efficiency of VOCs removal.

With a typical condenser, the cooling unit must be used to be controlled at relatively low operating temperatures, and the waste gas must remain in the condenser long enough to remove VOCs through condensation, ensuring a minimum concentration of VOCs in the treated waste gas. can do. However, in the high-tech industry, which produces a fairly large volume of waste gas with VOCs concentrations as low as 100ppmv to 1,000ppmv, the use of a common condensation process that lowers the temperature below -20 ° C to achieve high condensation efficiency is quite high. It will result in energy loss and equipment maintenance costs. Due to the design limitations of the general condensation system and the purpose of reducing the running costs, many domestic manufacturers face a common problem with condensation units with poor VOCs regeneration efficiency.

Many countries around the world have established very stringent industrial waste gas emission standards, including standards for concentration and odor standards for waste gas emitted. In the above stripping process, the DMSO contained in the stripper is a liquid having water solubility and low volatilization characteristics, and during the stripping process, DMSO is a gaseous pollutant such as dimethyl sulfide (DMS) and dimethyl disulfide (DMDS). Tends to form. However, DMS and DMDS, which cannot be completely removed through the condensation process, tend to produce odors even at low temperatures, which tend to easily adversely affect the surrounding living environment and should protect people from such substances.

Ozone has high oxidizing properties and is widely applied to flowing water and wastewater treatment in order to disinfect water or to remove organic compound portions from water. The reaction between ozone and organic compounds can be separated into direct reactions and indirect reactions. In general, the reaction can be accelerated by the presence of a suitable percentage of oxidant such as H ₂ O ₂ , OH ⁻ . From the ozone radical (radical) without ^{OH-generating} group or H ₂ O _2, OH ^-, and ^UV: a technique for generating an (ultraviolet light UV) and OH free radicals (radical) via the reaction of ozone Generally referred to as advanced oxidation processes (AOP). Currently industrially useful methods of producing ozone mainly include corona discharge, ultraviolet irradiation, sulfuric acid electrolsis, radiation exposure and the like. Among them, ozone generators for corona discharge are most often used to produce ozone. When using such an ozone generator, air or oxygen may be used as the gas source.

Nonthermal plasma (NTP) is one of the advanced oxidation processes, and has been continuously applied for the control and removal of air pollution since 1990 to show high removal efficiency. In non-thermal plasma treatment, high pressure is applied to the two electrodes to induce discharge. During the discharge process, electrons with high energy are produced by collisions with solutionmolecules, producing free radicals. Some of the free radicals can produce more ozone. All electrons, free electrons, and contaminants in contact with ozone having high oxidation characteristics can be immediately oxidized or decomposed to obtain purge air.

Therefore, the condensation regeneration system effectively increases the efficiency of the condensation regeneration system and reduces the power consumption to reach very low temperatures, as found in conventional condensers, while effectively eliminating VOCs residues from the waste gas through advanced catalytic oxidation. It has been attempted by the inventors to develop a method and apparatus for treating organic waste gases through adsorption processes and advanced catalytic oxidation processes.

It is a main object of the present invention to provide a high performance purification apparatus for treating organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process that can effectively treat organic waste gas by reducing the cost and time for maintaining the purification device. It is.

It is another object of the present invention to provide a process for the high performance treatment and purification of organic waste gases through condensation-adsorption processes and advanced catalytic oxidation processes.

Still another object of the present invention is to provide a high performance purification apparatus for treating organic waste gas through a condensation-adsorption process.

The purifying apparatus according to the present invention for achieving the above object comprises at least one condensation-resistant unit, comprising a condensing coil and a defrosting unit, disposed at a subsequent stage of the filter unit, and An advanced oxidation treatment unit.

Ice water, brine or coolant of 5 ° C to 10 ° C is circulated in the condensation coil of the condensation-resistant unit. Under these temperature conditions, water vapor coats the stripper's frost, resulting in the formation of nuclear condensation, and the water (moisture) and VOCs form a liquid film on the wall surface of the condensation coil. Since a large amount of stripper has a high boiling point and is easily soluble in water, when waste gas is transferred from the stripper through the liquid film, the waste gas is absorbed by the liquid film and effectively removed by defrosting. This design yields complex effects including low temperature condensation, nuclear condensation production, and liquid film adsorption. Unlike conventional condensers, where only a single concept of saturated condensation is applied for condensing VOCs at low temperatures, the purifier of the present invention has an efficient upgrade in condensation and recovery characteristics of VOCs, and the high boiling point produced in high-tech industries. It is well suited for applications in the treatment of large volumes of waste gases containing various VOCs.

The high performance purification apparatus of the present invention may include, for example, at least two condensation-frost removal units arranged in series, wherein ice water of 5 ° C to 10 ° C is circulated in the condensation coils of the two condensation-frost removal units. The condensation coil located in front of the two condensation coils is mainly used at low temperatures, but also assists in the condensation-adsorption process and the generation of nuclear condensation. On the other hand, the condensation coil located at the rear is mainly used to achieve the generation of nuclear condensation and to form a condensed liquid film for adsorbing VOCs of waste gas. The defrost unit removes moisture and VOCs moisture bubbles from the waste gas. Removed moisture and VOCs moisture drops are collected in a storage tank and regenerated. Therefore, in the present invention, the number of condensation-defrosting units is not particularly limited, but may be determined depending on various other factors such as the type of organic waste gas to be treated, the temperature of the gas flow, the size of the waste gas, and the like. Furthermore, the condensation-resistant units are arranged in series or in parallel.

In the purifying apparatus of the present invention, a heat exchanger for heat regeneration may be arranged between the filter unit and the defrost unit. In order to save energy while increasing the condensation efficiency, the flow of cold gas discharged from the rear of the purifying device of the present invention can be directed to a heat regeneration heat exchanger for cooling down the feed gas by a duct. have.

In the purifying apparatus of the present invention, the flow field formed over the condensation coil is a laminar flow instead of generally known turbulent flow, and is about 1.5 m / s or less, preferably about It has a surface wind speed of 1.0 m / s.

In the purifying apparatus of the present invention, there are no specific limitations on the advanced oxidation unit which may include an ozone supply and a catalyst or a non-thermal plasma electrode and a catalytic oxidation unit. Preferably, the advanced oxidation unit may comprise a non-thermal plasma electrode and a catalytic oxidation unit.

In addition, a method of treating and purifying organic waste gas with high performance through a condensation-adsorption process and an advanced catalytic oxidation process according to another embodiment of the present invention is as follows.

First, the organic waste gas is treated through a condensation-adsorption process and an advanced catalytic oxidation process, and at least one condensation-anti-frost unit including a condensation coil and an anti-defrost unit, and a high-performance purification device including an advanced oxidation treatment unit are provided. Making; Circulating ice water, brine or coolant at 5 ° C. to 10 ° C. for a predetermined period of time in the condensation coil of the condensation-resistant unit to form a liquid film of nuclear condensation and condensed water on the wall surface of the condensation coil. ; Directing the organic waste gas to a purification device through a filter unit, prefiltering the organic waste gas, and uniformly dispersing the flow of the gas; Directing the organic off-gas through the condensation coil of the condensation-protection unit such that the organic waste gas is condensed and adsorbed by a liquid film; And treating the organic waste gas located at a subsequent stage of the condensation-resistant unit using the advanced oxidation treatment unit.

In the high-performance purification method of the present invention, for example, at least two condensation-frost removal units are arranged in series, and the condensation coils of the two condensation-frost removal units include ice water and salt water of 5 ° C to 10 ° C. Or coolant is circulated. As a result, a nuclear condensation product and a liquid film of condensed water are formed on the wall surface of the coil. After generating and condensing the nuclear condensation generated in the condensation process, by utilizing the liquid film adsorption mechanism in the balance between liquid and gas phase, VOCs in the waste gas can be adsorbed and removed more effectively. The forward condensation coil of the two condensation coils is mainly used at low temperatures, but also assists in the condensation-adsorption process and the generation of nuclear condensation. On the other hand, the condensation coil located at the rear is mainly used to achieve the generation of nuclear condensation and to form a condensed liquid film for adsorbing VOCs of waste gas. The defrost unit removes moisture and VOCs moisture bubbles from the waste gas. Removed moisture and VOCs moisture drops are collected in a storage tank and regenerated. Therefore, in the present invention, the number of condensation-frost removal units is not particularly limited, but may be determined depending on various other factors such as the type of organic waste gas to be treated, the temperature of the gas flow, the size of the waste gas, and the like. Furthermore, the condensation-resistant units are arranged in series or in parallel.

In the purifying method of the present invention, a heat exchanger for heat recovery mounted between the filter unit and the defrosting unit may be arranged. In order to save energy while increasing the condensation efficiency, the flow of cold gas discharged from the rear of the purifying apparatus of the present invention can be directed to a heat regeneration heat exchanger for stabilizing the feed gas by the duct.

In the purifying method of the present invention, the flow field formed over the condensation coil is generally laminar instead of turbulent flow, and has a surface wind velocity of about 1.5 m / s or less, preferably about 1.0 m / s.

In the purifying method of the present invention, there are no specific limitations on the advanced oxidation unit which may include an ozone supply and a catalyst or a non-thermal plasma electrode and a catalytic oxidation unit. Preferably, the advanced oxidation unit may comprise a non-thermal plasma electrode and a catalytic oxidation unit.

In the purifying method of the present invention, when organic waste gas is treated in the condensation-resistant unit, most organic components of the waste gas are condensed and adsorbed, and the treated gases discharged from the outlet of the purifying device have a very high humidity. Has It is thus advantageous for these gases to ozone oxidize at the rear end of the developed oxidation treatment unit. With ozone oxidation and catalyst, condensation and adsorption can remove residual malodorous gases such as DMS and DMDS that are not fully adsorbed.

In the purifying method of the present invention, the developed oxidation processing unit may include a non-thermal plasma electrode and a catalytic oxidation unit. When high pressure is applied to the non-thermal plasma electrode for discharging, gas molecules are excited to dissociate or free to form many activating particles such as metastable molecules, free radicals, or ions. Such particles can overcome obstacles from energy levels that result in bond breakdown of the initially stable gas molecules in the gas flow. Moreover, high pressure discharge at nonthermal plasma electrodes also produces ozone. Such ozone oxidation and catalyst can decompose VOCs and odor gases in waste gas.

The purifying device of the present invention is arranged at the rear end of the filter unit and includes at least one condensation-defrosting unit comprising a condensation coil and a defrosting unit.

The high performance purification apparatus of the present invention may include, for example, at least two condensation-frost removal units arranged in series, wherein ice water of 5 ° C to 10 ° C is circulated in the condensation coils of the two condensation-frost removal units. The forward condensation coil of the two condensation coils is mainly used at low temperatures, but also assists in the condensation-adsorption process and the generation of nuclear condensation. On the other hand, the condensation coil located at the rear is mainly used to achieve the generation of nuclear condensation and to form a condensed liquid film for adsorbing VOCs of waste gas. The defrost unit removes moisture and VOCs moisture bubbles from the waste gas. Removed moisture and VOCs moisture drops are collected in a storage tank and regenerated. Therefore, in the present invention, the number of condensation-frost removal units is not particularly limited, but may be determined depending on various other factors such as the type of organic waste gas to be treated, the temperature of the gas flow, the size of the waste gas, and the like. Furthermore, the condensation-resistant units are arranged in series or in parallel.

Ice water, brine or coolant of 5 ° C to 10 ° C is circulated in the condensation coil of the condensation-defrosting unit. Under these temperature conditions, water vapor coats the stripper's frost, resulting in the formation of nuclear condensation, and the water and VOCs form a liquid film on the wall surface of the condensation coil. Since a large amount of stripper has a high boiling point and is easily dissolved in water, when waste gas is transferred from the stripper through the liquid film, the waste gas is absorbed by the liquid film and effectively removed by defrosting. . This design yields complex effects including low temperature condensation, nuclear condensation production, and liquid film adsorption. Unlike conventional condensers, where only a single concept of saturated condensation is applied for condensing VOCs at low temperatures, the purifier of the present invention has an efficient upgrade in condensation and recovery characteristics of VOCs, and the high boiling point produced in high-tech industries. It is well suited for applications in the treatment of large volumes of waste gases containing various VOCs.

The high performance purification apparatus of the present invention may include, for example, at least two condensation-frost removal units arranged in series, wherein ice water of 5 ° C to 10 ° C is circulated in the condensation coils of the two condensation-frost removal units. The forward condensation coil of the two condensation coils is mainly used at low temperatures, but also assists in the condensation-adsorption process and the generation of nuclear condensation. On the other hand, the condensation coil located at the rear is mainly used to achieve the generation of nuclear condensation and to form a condensed liquid film for adsorbing VOCs of waste gas. The defrost unit removes moisture and VOCs moisture bubbles from the waste gas. Removed moisture and VOCs moisture drops are collected in a storage tank and regenerated. Therefore, in the present invention, the number of condensation-defrosting units is not particularly limited, but may be determined depending on various other factors such as the type of organic waste gas to be treated, the temperature of the gas flow, and the size of the waste gas. . Furthermore, the condensation-resistant units are arranged in series or in parallel.

In the purifying apparatus of the present invention, a heat exchanger for heat regeneration may be arranged at the inlet of the condensation unit. In order to save energy while increasing the condensation efficiency, the flow of cold gas discharged from the rear of the purifying apparatus of the present invention can be directed to a heat regeneration heat exchanger for stabilizing the feed gas by a duct.

In the purifying apparatus of the present invention, the flow field formed over the condensation coil is generally laminar instead of turbulent flow, and has a surface wind velocity of about 1.5 m / s or less, preferably about 1.0 m / s.

According to the present invention, by using the condensation-adsorption process and the advanced catalytic oxidation process, it is possible to easily remove the high boiling point VOCs. By using this approach, it is possible to increase the VOCs condensation and regeneration effect, and to reduce the running costs for low energy consumption, environmental protection and energy saving requirements.

1 is a schematic view showing a high performance purification apparatus for treating organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process according to a preferred embodiment of the present invention. Referring to the drawings, the purification apparatus comprises a blower 10, first and second condensation-resistant units 30 and 31, advanced oxidation processing unit 40, and which may be connected in series and / or in parallel; A bypass duct 50. The first condensation-resistant unit 30 includes a first condensation coil 301 and a first frost resistant unit 302. The second condensation-freezing unit 31 includes a second condensation coil 311 and a second frost-proofing unit 312. The developed oxidation treatment unit 40 may include an ozone supply 42 and a catalytic oxidation unit 41 or a non-thermal plasma electrode (not shown) and a catalytic oxidation unit 41.

As shown in FIG. 1, in a method for purifying waste gas through a condensation-adsorption process and an advanced oxidation process using the apparatus of the present invention, ice water having a temperature of about 5 ° C. to 10 ° C. is first and second. A liquid phase made of water condensed on the wall surface of the first and second condensation coils 301 and 311 by circulating the inside of the first and second condensation coils 301 and 311 of each of the condensation-protection units 30 and 31 for a predetermined time period. Form a film. Next, in order to pre-filter the organic waste gas and to uniformly distribute the flow of the gas, the blower 10 is driven to filter the filter unit 20 located in front of the condensation-resistant prevention units 30 and 31. Pass the organic waste gas through. Thereafter, the organic waste gas is guided through the first condensation-preventing unit 30, so that the temperature drops. The heat exchanger 60 for regenerating heat may be mounted at the rear of the filter unit 20 to sharply drop the temperature of the waste gas and increase the condensation efficiency. Under these temperature conditions, since there is a liquid film made of condensed water formed on the wall surface of the first condensation coil 301, the phenomenon of nuclear condensation creation occurring during the condensation process and the liquid phase generated after adsorption- The adsorption mechanism of the liquid film formed in the balance of the gas phase effectively adsorbs and removes the VOCs in the waste gas. The waste gas stream treated in the first condensation coil 301 is directed through the first defrost unit 302 to remove water (moisture) and VOCs moisture droplets in the waste gas. Thereafter, the waste gas stream is further guided continuously through the second condensation coil 311 and the second anti-frost unit 312, thereby repeating the condensation-adsorption and anti-frost process. Here, the flow field formed over the condensation coils 301, 311 is a laminar flow having a surface wind speed of about 1.5 m / s or less, for example 1.0 m / s to 1.5 m / s. The waste gas stream exiting the second condensation-preventing unit 31 contains only a small amount of water insoluble and low boiling point VOCs, has a high humidity, and can be further directed to the advanced oxidation treatment unit 40. . At this time, ozone is supplied from the ozone supply 42 to the oxidation processing unit 40 which is driven together with the catalytic oxidation unit 41 to oxidize VOCs having low water solubility and low boiling point remaining in the waste gas stream. The oxidized waste gas stream conforms to the officially established emission standard and is discharged from the discharge element into the atmosphere. The organic solvent obtained after the condensation-adsorption process is collected in storage tanks 303 and 313, and the regeneration process is processed or purified using an in-house purification device for reuse.

A high performance purification apparatus for treating organic waste gas through a condensation-adsorption process according to the invention comprises at least one condensation unit comprising at least one condensation coil; And at least one anti-defrost unit disposed behind (or below) the condensation unit. The condensation unit and the anti-frost unit can be arranged in series, in parallel or in series and in parallel. The condensation coil comprises ice water, brine or coolant circulating therein, and the ice water, brine or coolant is preferably provided at a temperature of 5 ° C to 10 ° C. A heat exchanger for heat regeneration can be mounted at the inlet of the condensation unit. The flow field formed over the condensation coil is a laminar flow with a surface wind velocity of about 1.5 m / s or less.

The present invention also provides a method for high performance treatment and purification of organic waste gases through condensation-absorption processes and advanced catalytic oxidation processes. This method includes the following steps.

(1) First, a high performance apparatus for treating and purifying organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process is provided. The purification apparatus includes a blower, a filter unit, at least one condensation-resistant unit and an advanced oxidation treatment unit. The condensation-defrosting unit includes a condensation coil and an defrosting unit, and the advanced oxidation unit includes an ozone supply and a catalytic oxidation unit or a non-thermal plasma electrode and a catalytic oxidation unit. Condensation-resistant units are arranged in series or in parallel in the purification apparatus.

(2) Ice water, brine or coolant at 5 ° C to 10 ° C is allowed to circulate in the condensation coil of the condensation-defrost unit for a predetermined period of time. As a result, nuclear condensation is generated and a liquid film of condensed water is formed on the wall surface of the condensation coil.

(3) Induce organic exhaust gas through the condensation coil of the condensation-protection unit. As a result, nuclear condensation is formed, frost is increased and condensed in the area in terms of size, and the organic waste gas is adsorbed by the liquid film. Next, using a defrost unit, remove moisture and VOCs moisture drops from the waste gas.

(4) The developed oxidation treatment unit is used to treat organic waste gas located behind the condensation-resistant unit.

Here, a heat exchanger for heat regeneration can be mounted between the filter unit and the condensation-resistant unit. In addition, the waste gas is supplied into the purification apparatus at a flow rate of about 1.5 m / s or less, such as 1.0 m / s.

In the present invention, a gas chromatograph-mass spectrometer (GC / MS) is used to perform quantitative and qualitative analysis of contaminants caused by the stripping process, as well as condensate absorbent efficiency analysis. In addition, the performance of the method and apparatus of the present invention is a procedure for testing in-air VOCs in Taiwan publication No. 14374, established by the Environmental Protection Agency, to establish a standard for detecting ppb-level VOCs concentrations. The steel sampling barrel / Gas Chromatograph-Mass Spectrometer Method (NIEA A715.11B) is tested and analyzed according to the Procedures for Testing VOCs in Air-Stainless Steel Sampling Barrel / Gas Chromatograph-Mass Spectrometer Method (NIEA A715.11B). As a result, the test method is based on MEA for converting gases such as MEA, DMSO, and BDG, which are entirely water soluble and have high boiling points, from gas phase to liquid phase (decomposed into deionized water). Using an impinger method for analyzing DMSO and BDG, followed by gas chromatograph and flame ion detector (GC-FID) and Chromatography (IC) is used to analyze the results.

In addition, another experiment of the present invention is an analysis of the correlation between the VOCs removal efficiency and the boiling point and Henry constant of the VOCs.

This experiment is carried out through four sampling and analysis in stripping process with different productivity. The results of four samplings and analyzes are calculated and averaged to obtain the results of the experiment. As indicated in the analysis, among the VOCs in the waste gas generated during the stripping process, 92.3% MEA, 4.86% DMSO, 1.2% DMS, 0.88% IPA, 0.5% DMDS, 0.13% NMP, and Trace amounts of toloene, N, N-dimethylformamide (DMF) and acetone.

2 is a graph showing the correlation between the boiling point of chemical components and the removal efficiency of organic waste gas of the purifying apparatus of the present invention. After treating the VOCs waste gas using the apparatus and method according to the preferred embodiment of the present invention, the VOCs concentration value was analyzed by GC / MS at the outlet of the purifying apparatus of the present invention, which contained MEA, DMSO and NMP. High boiling VOCs have been removed with good efficiency of over 80%, but the removal efficiencies of other types of VOCs have been found to tend to increase with increasing boiling point of VOCs.

3 is a graph showing the correlation between the Henry constant of the chemical component and the removal efficiency of the organic waste gas of the purifying apparatus of the present invention. With the novel condensation-resistant unit of the invention capable of removing VOCs through the adsorption mechanism of liquid films, the VOCs in the waste gas can be removed through the usual low temperature condensation mechanism, as well as the generation and adsorption of nuclear condensation. It can also be removed with a liquid film of condensed water through the mechanism. Therefore, there is a close relationship between the efficiency of VOCs removal of the present invention and the Henry's constant of VOCs. As shown in FIG. 3, the removal efficiency of most VOCs is directly proportional to the Henry's constant of the VOCs. This indicates that in the condensation-adsorption process designed by the present invention, the liquid film and high boiling point VOCs formed through the condensation of air (humidity) provide an important VOCs adsorption and removal mechanism in the present invention.

DMS emits extreme odors, has the lowest boiling point of all VOCs, and is known to have a Henry's constant of less than 0.48 mol / (kg × bar) in water at 25 ° C. However, as can be seen from FIGS. 2 and 3, the absorbent for condensation of the present invention still provides a higher DMS (and DMDS) removal efficiency than the removal efficiency of other VOCs with similar boiling point and Henry's constant. This is because DMS (and DMDS) dissolve very easily in DMSO. That is, as indicated by the white marks in FIGS. 2 and 3, liquid DMSO, which allows about 50% removal efficiency for DMS (and DMDS), tends to adsorb DMS (and DMDS). If the VOCs waste gas is further processed in an advanced oxidation treatment unit 40 located at the rear of the purification apparatus of the present invention, the removal efficiency for DMS (and DMDS) is even as indicated by the black marks in FIGS. 2 and 3. It can reach as high as 80% or more.

Further experiments were conducted to analyze the correlation between the VOCs removal efficiency of the present invention and the flow rate of VOCs waste gas supplied from the purification apparatus of the present invention.

In the present experiment, nine tests were performed to investigate the efficiency of treating VOCs of the condensate absorbent of the present invention while the supplied VOCs waste gases were provided at different flow rates under conditions of varying productivity in the stripping process. It was. Here, VOCs treatment efficiency is calculated based on total hydrocarbons. The experimental results show that when the VOCs waste gas has a flow rate of 3.0 m / s, the condensing absorbent of the present invention provides an average VOCs removal efficiency of about 58%, and when the VOCs waste gas has a flow rate of 1.5 m / s, It provides an average VOCs removal efficiency of about 83% and indicates that if the VOCs waste gas has a flow rate of 1.0 m / s, it provides an average VOCs removal efficiency of at least 85%.

Therefore, in the apparatus of the present invention, to effectively and advantageously adsorb VOCs having a high boiling point and hydrophilicity by a liquid film of condensed water or VOCs, Reynolds number (Re _Dh ), that is, a hydraulic diameter ( The design value for the hydraulic diameter should be 514 (1.5m / s) or less. On the other hand, in this manner, the VOCs concentration at the outlet can be much smaller than the saturation concentration of VOCs at the outlet due to the nuclear condensation generating effect and the liquid film adsorption effect. Therefore, selecting a relatively low VOCs waste gas flow rate is advantageous for improving the VOCs removal efficiency of the present invention.

In fact, 60% of the VOCs generated during the stripping process in the semiconductor wafer production industry are high boiling VOCs such as MEA, DMSO, BDG and NMP. By treatment with the apparatus and method of the present invention, more than 80% of these high boiling point VOCs can be removed. From the results of the above experiments and tests and analyzes, the apparatus and method of the present invention for treating and purifying VOCs using a combination of low temperature surface agglomeration, nuclear condensation generating effects, and liquid film adsorption mechanisms using advanced catalytic processes are highly It is very suitable for the treatment of boiling VOCs. In addition, the present invention has the advantage of having excellent VOCs condensation and regeneration effects, low energy consumption, and effectively reduced running costs for environmental protection and energy saving requirements. Therefore, the present invention is particularly valuable and practical for use in the high tech industry.

1 schematically shows a high performance purification apparatus for treating organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process according to a preferred embodiment of the present invention;

2 is a graph showing the correlation between the boiling point of chemical components and the removal efficiency of organic waste gas of the purifying apparatus of the present invention, and

3 is a graph showing the correlation between the Henry constant of the chemical component and the removal efficiency of the organic waste gas of the purifying apparatus of the present invention.

<Description of the symbols for the main parts of the drawings>

10 blower 30,31 first and second condensation-frost prevention unit

40: advanced oxidation treatment unit 50: bypass duct

Claims (20)

At least one condensation and defrosting unit, comprising a condensation coil and a defrosting unit, disposed subsequently to the filter unit; And A high performance purification apparatus for treating organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process comprising an advanced oxidation treatment unit. The method of claim 1, Wherein the condensation-desorption units are arranged in series, in parallel or in series and in parallel in the apparatus. The method of claim 3, wherein The condensation coil is a purification device including ice water of 5 ° C to 10 ° C circulating therein. The method of claim 1, And a heat exchanger for heat recovery mounted between said filter unit and said defrost unit. The method of claim 1, The flow field formed over the condensation coil is a laminar flow having a surface wind velocity of about 1.5 m / s or less. The method of claim 1, The advanced oxidation treatment unit comprises an ozone feeder and a catalytic oxidation unit. The method of claim 1, The advanced oxidation treatment unit includes a non-thermal plasma electrode and a catalytic oxidation unit. Processing an organic waste gas through a condensation-adsorption process and an advanced catalytic oxidation process, and providing a high performance purification apparatus comprising at least one condensation-anti-frost unit and an advanced oxidation treatment unit comprising a condensation coil and an anti-frost unit. ; Circulating ice water, brine, or a coolant of 5 ° C. to 10 ° C. for a predetermined period of time in the condensation coil of the condensation-resistant unit to form a liquid film of nuclear condensation and condensed water on the wall surface of the condensation coil. step; The organic exhaust gas is led through the condensation coil of the condensation-preventing unit, so that nuclear condensation formation is formed, frost is increased and condensed in size, so that the organic waste gas is adsorbed by the liquid film, Removing water (moisture) and VOCs droplets from the waste gas using the anti-frost unit; And Treating and purifying the organic waste gas through the condensation-adsorption process and the advanced catalytic oxidation process comprising the step of treating the organic waste gas located after the condensation-resistant unit using the advanced oxidation treatment unit. How to. The method of claim 8, And wherein the condensation-protection unit comprises at least one, the condensation-protection unit is arranged in series, in parallel, or in series and in parallel. The method of claim 8, The condensation coil is a purification method comprising ice water of 5 ° C to 10 ° C circulating therein. The method of claim 8, And a heat exchanger for heat regeneration mounted between the filter unit and the condensation-resistant unit. The method of claim 8, And purifying the waste gas at a flow rate of about 1.5 m / s or less. The method of claim 8, And purifying the waste gas at a flow rate of about 1.0 m / s. The method of claim 8, The advanced oxidation treatment unit comprises an ozone feeder and a catalytic oxidation unit. The method of claim 8, The advanced oxidation treatment unit comprises a non-thermal plasma electrode and a catalytic oxidation unit. At least one condensation unit comprising at least one condensation coil; And And a high performance purification apparatus for treating organic waste gas through a condensation-adsorption process comprising at least one anti-defrost unit disposed behind the condensation unit. The method of claim 16, And the condensation unit and the anti-frost unit are arranged in series, in parallel, or in series and in parallel. The method of claim 16, The condensation coil includes ice water, brine, or coolant circulating therein, The ice water, brine or coolant is supplied at a temperature of 5 ° C to 10 ° C. The method of claim 16, And a heat exchanger for heat regeneration mounted to an inlet of the condensation unit. The method of claim 16, The flow field formed over the condensation coil is a laminar flow having a surface wind velocity of about 1.5 m / s or less.

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