Facility for removing silicon tetrafluoride gas and producing anhydrous hydrogen fluoride

Abstract

According to the present invention, a dry gas decomposition apparatus for decomposing silicon tetrafluoride gas to produce hydrogen fluoride gas; and a condensation apparatus for condensing the hydrogen fluoride gas to produce anhydrous hydrofluoric acid are provided, wherein the dry gas decomposition apparatus comprises a dry reactor in which the silicon tetrafluoride gas reacts with superheated steam to decompose and the hydrogen fluoride gas and silicon dioxide particles are produced, and the condensation apparatus comprises a condenser for condensing the hydrogen fluoride gas and a cooling unit for cooling the hydrogen fluoride gas before the hydrogen fluoride gas is supplied to the condenser, and the cooling unit comprises a microbubble device for supplying the hydrogen fluoride gas to water in the form of microbubbles.

Description

Technology Field

[0001] The present invention relates to a technology for removing silicon tetrafluoride gas, and more specifically, to a technology for removing silicon tetrafluoride gas and producing anhydrous hydrofluoric acid as a byproduct generated during the process of removing silicon tetrafluoride gas. Background Technology

[0002] Silicon tetrafluoride (SiF4) is a compound formed by the combination of silicon and fluorine. While it plays a crucial role primarily in semiconductor manufacturing processes and the chemical industry, it is a hazardous substance that requires strict caution during handling. Therefore, it is necessary to remove silicon tetrafluoride to prevent its release into the atmosphere. However, there is a problem in that commonly used dry silicon tetrafluoride removal systems have very low removal rates. Prior art literature

[0003] Republic of Korea Registered Patent Publication No. 10-1944199 (2019.01.30.) Republic of Korea Registered Patent Publication No. 10-0492104 (2005.06.10.) The problem to be solved

[0004] The objective of the present invention is to provide a facility for removing silicon tetrafluoride gas and producing anhydrous hydrofluoric acid. means of solving the problem

[0005] In order to achieve the above-mentioned objective of the present invention, according to one aspect of the present invention, a dry gas decomposition apparatus for decomposing silicon tetrafluoride gas to produce hydrogen fluoride gas; and a condensation apparatus for condensing the hydrogen fluoride gas to produce anhydrous hydrofluoric acid are provided, wherein the dry gas decomposition apparatus comprises a dry reactor in which the silicon tetrafluoride gas reacts with superheated steam to decompose and the hydrogen fluoride gas and silicon dioxide particles are produced, and the condensation apparatus comprises a condenser for condensing the hydrogen fluoride gas and a cooling unit for cooling the hydrogen fluoride gas before the hydrogen fluoride gas is supplied to the condenser, and the cooling unit comprises a microbubble device for supplying the hydrogen fluoride gas to water in the form of microbubbles. Effects of the invention

[0006] According to the present invention, all the objectives of the invention described above can be achieved. Specifically, since superheated steam reacts with silicon tetrafluoride gas in a dry reactor, the removal rate of silicon tetrafluoride increases, and additionally, the production rate of hydrogen fluoride as a byproduct also increases, so anhydrous hydrofluoric acid can be produced efficiently. Brief explanation of the drawing

[0007] FIG. 1 is a block diagram schematically showing the configuration of a silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to one embodiment of the present invention. FIG. 2 is a block diagram schematically showing the configuration of a dry gas decomposition equipment equipped in the silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility shown in FIG. 1. FIG. 3 is a side view of a dry reactor equipped in the gas decomposition device shown in FIG. 2, with the interior visible. Figure 4 is a plan view of the dry reactor shown in Figure 3, with the interior visible. FIG. 5 is a side view of a dry reactor according to another embodiment of the present invention, shown with the interior visible. Figure 6 is a plan view of the dry reactor shown in Figure 5, with the interior visible. Figure 7 is a block diagram schematically showing the configuration of a condensation device equipped in the silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility shown in Figure 1. FIG. 8 illustrates in detail the configuration of the first microbubble device in the condensation equipment shown in FIG. 7, and shows the state during operation. FIG. 9 illustrates in detail the configuration of the first microbubble device in the condensation equipment shown in FIG. 7, and shows the state before operation. FIG. 10 illustrates in detail the configuration of the second microbubble device in the condensation equipment shown in FIG. 7, and shows the state during operation. FIG. 11 illustrates in detail the configuration of the second microbubble device in the condensation equipment shown in FIG. 7, and shows the state before operation. Specific details for implementing the invention

[0008] Hereinafter, the configuration and operation of an embodiment of the present invention will be described in detail with reference to the drawings.

[0009] FIG. 1 shows a schematic configuration of a silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to one embodiment of the present invention as a block diagram. Referring to FIG. 1, the silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility (1) includes a dry gas decomposition equipment (10) that decomposes silicon tetrafluoride (SiF4) gas to produce hydrogen fluoride (HF) gas, and a condensation equipment (1000) that condenses the HF gas discharged from the dry gas decomposition equipment (10) to produce anhydrous hydrofluoric acid.

[0010] The dry gas decomposition equipment (10) decomposes silicon tetrafluoride (SiF4) gas using a hydrolysis reaction. Figure 2 shows the configuration of the dry gas decomposition equipment (10) as a block diagram. Referring to FIG. 2, the dry gas decomposition equipment (10) comprises a dry reactor (100) in which a decomposition reaction for SiF4 gas takes place, a superheated steam supply unit (20) that supplies superheated steam (H2O) to the dry reactor (100) for hydrolysis of SiF4 gas, a compressed air supply unit (30) that supplies compressed air to the superheated steam supplied to the dry reactor (100), a heater (40) that heats the SiF4 gas flowing into the dry reactor (100), a cyclone filter (52) that collects particles from the gas discharged from the dry reactor (100), a bag filter (54) that further collects particles from the gas discharged from the cyclone filter (52), and a mixer (56) that mixes the HF gas discharged from the cyclone filter (52) with the outside air to cool it.

[0011] The dry reactor (100) decomposes SiF4 gas through a hydrolysis reaction. The hydrolysis reaction of SiF4 gas occurring in the dry reactor (100) is as shown in Reaction Equation 1 below.

[0012] [Reaction Equation 1]

[0013] SiF4(g) + 2H2O(g) → SiO2(s) + 4HF(g)

[0014] As can be seen from reaction equation 1, in a dry reactor (100) at a temperature of 180 to 220°C, SiF4 gas is decomposed by a hydrolysis reaction, and silicon dioxide (SiO2) particles in the form of fine powder and hydrogen fluoride (HF) gas are produced. The SiO2 particles and HF gas produced by the hydrolysis reaction of SiF4 gas are discharged from the dry reactor (100) and flow into a cyclone filter (52).

[0015] The structure of a dry reactor (100) is illustrated in FIGS. 3 and 4. Referring to FIGS. 3 and 4, the dry reactor (100) comprises a reaction body (110) and a plurality of injection nozzles (160) coupled to the reaction body (110). Although the dry reactor (100) is depicted as a single unit in the drawings, the present invention is not limited thereto. A plurality of dry reactors (100) may be installed and used in parallel, and this also falls within the scope of the present invention.

[0016] The reaction body (110) provides a passage (120) that extends along a generally straight central axis (X) inside. The dry reactor (100) operates by being positioned so that the passage (120) extends along the height direction as illustrated. The passage (120) has a generally circular cross-sectional shape. The reaction body (110) is provided with an inlet (140) communicating with the passage (120) and an outlet (150) communicating with the passage (120) and located below the inlet (140) and spaced apart from the inlet (140). In the passage (120), the direction from the inlet (140) toward the outlet (150) becomes the direction of flow. SiF4 gas at approximately 220°C is introduced into the passage (120) through the inlet (140), and SiO2 particles and HF gas generated by the hydrolysis reaction of SiF4 gas are discharged from the passage (120) through the outlet (150). A flushing gas inlet (155) is located in the passage (120) opposite the outlet (150).

[0017] The passage (120) has a spray section (122) extending over a portion of the section between the inlet (140) and the outlet (150), a throat section (124) extending over a portion between the spray section (122) and the outlet (150), a contraction section (126) extending over a portion between the spray section (122) and the throat section (124), and a diffusion section (128) formed over a portion between the throat section (124) and the outlet (150).

[0018] The injection section (122) extends along the height direction over a portion of the section between the inlet (140) and the outlet (150). The cross-sectional area (D) of the injection section (122) S ) is generally maintained at a constant level. In the injection section (122), superheated steam is injected from a plurality of injection nozzles (160). In the injection section (122), turbulence is formed, increasing the reaction rate between SiF4 gas and superheated steam.

[0019] The neck section (124) extends along the height direction over a portion of the section between the spray section (122) and the outlet (150). The cross-sectional area of ​​the neck section (124) is smaller than the cross-sectional area of ​​the spray section (122). The diameter (D) of the neck section (124) T ) is maintained constant, so the cross-sectional area of ​​the neck section (124) is also maintained constant. In this embodiment, the length (L) of the neck section (124) T ) is the diameter (D) of the neck section (124). T It is explained as being generally the same as ). The neck section (124) and the injection section (122) are connected by the contraction section (126).

[0020] The contraction section (126) extends over a portion of the section between the injection section (122) and the neck section (124). The cross-sectional area of ​​the contraction section (126) decreases as it goes down the downstream side. In this embodiment, the inner surface of the contraction section (126) is inclined at an angle of 20 to 25° with respect to the central axis line (X) so that the cross-sectional area of ​​the contraction section (126) decreases, and the length (L) of the contraction section (126) C ) is the diameter (D) of the neck section (124). T It is explained that it is about twice the size of ). In this embodiment, the upper end of the upstream side of the contraction section (126) is connected to the lower end of the downstream side of the injection section (122), and the lower end of the downstream side of the contraction section (126) is connected to the upper end of the upstream side of the diffusion section (128). The flow velocity increases in the contraction section (126) so that the components (HF gas, SiO2 particles, etc.) within the injection section (122) move well along the flow direction.

[0021] The diffusion section (128) extends over a portion of the area between the neck section (124) and the outlet (150). The cross-sectional area of ​​the diffusion section (128) increases as it goes downstream. In this embodiment, the inner surface of the diffusion section (128) is inclined at an angle of 5 to 7° with respect to the central axis (X) to increase the cross-sectional area of ​​the diffusion section (128), and the length (L) of the diffusion section (128) D ) is the diameter (D) of the neck section (124). T It is explained as being 6 to 8 times )

[0022] A plurality of injection nozzles (160) are coupled to the reaction body (110). Each of the plurality of injection nozzles (160) injects superheated steam into the injection section (122) of the reaction body (110). In this embodiment, the injection nozzles (160) are described as having six, but the invention is not limited thereto. It is preferable that the number of injection nozzles (160) be an even number. The nozzle nozzles (162) provided in each of the plurality of injection nozzles (160) are positioned at equal intervals in sequence along the circumferential direction of the passage (120). The plurality of nozzle nozzles (162) are positioned alternately up and down along the circumferential direction. That is, three of the six nozzle nozzles (162) are located at the same height relatively above, and the remaining three are located at the same height relatively below. The injection direction of each of the plurality of injection nozzles (160) is formed off the central axis (X) on the cross-section of the passage (120) as shown in FIG. 4. It is preferable that the injection direction of each of the injection nozzles (160) all form an angle of inclination (a) of 20 to 30° with respect to the radial direction in the same direction, and approximately 25° is most preferable. Although FIG. 4 shows the injection direction of the plurality of injection nozzles (160) as being counterclockwise with respect to the central axis (X), they may be installed so that the injection direction is clockwise, and this is also within the scope of the present invention. As shown in FIG. 3, among the six injection nozzles (160), two opposing injection directions are formed at an angle of inclination (b) with the central axis (X) so as to face downstream, and the remaining four injection directions are generally perpendicular to the extension direction of the passage (120). The above inclination angle (b) is preferably 70 to 80°, and is most preferably about 75°. A swirl is formed by spraying through a plurality of spray nozzles (160) shown in FIGS. 3 and 4, thereby improving reactivity.The injection direction of the multiple injection nozzles (160) can be varied. For example, among the multiple injection nozzles (160), at least one of the injection nozzles located on the upstream side (upper) may have an injection direction facing downstream, and at least one of the injection nozzles located on the downstream side (lower) may have an injection direction facing upstream. Additionally, the swirl formation direction of the injection nozzles located on the upstream side (upper) and the swirl formation direction of the injection nozzles located on the downstream side (lower) may be formed in opposite directions. The reaction rate between SiF4 gas and water vapor can be controlled according to the length of the downstream section of the injection nozzle (160) in the injection section (122).

[0023] Although not illustrated, the dry reactor (100) further comprises a heater for maintaining the operating temperature. The operating temperature of the dry reactor (100) is preferably 180 to 220°C. A heater may not be provided, and this is also within the scope of the present invention.

[0024] Referring to FIG. 2, the superheated steam supply unit (20) supplies superheated steam that reacts with and decomposes SiF4 gas to the dry reactor (100). The superheated steam supply unit (20) receives superheated steam produced from the outside. The superheated steam supply unit (20) is equipped with a pressure regulator (27) that regulates the pressure of the superheated steam supplied to the dry reactor (100) and a flow meter (29) that measures the flow rate of the superheated steam supplied to the dry reactor (100). The pressure regulator (27) and the flow meter (29) are positioned sequentially along the direction of flow on the superheated steam supply line (20a) through which the superheated steam flows to the dry reactor (100).

[0025] The pressure regulator (27) regulates the pressure of the superheated steam supplied to the dry reactor (100) on the superheated steam supply line (20a).

[0026] A flow meter (29) is installed downstream of the pressure regulator (27) on the superheated steam supply line (20a) to measure the flow rate of superheated steam flowing along the superheated steam supply line (20a) and supplied to the dry reactor (100).

[0027] The compressed air supply unit (30) supplies compressed air to the superheated steam supply line (20a) through which superheated steam supplied to the dry reactor (100) flows. The injection performance of superheated steam in the dry reactor (100) can be controlled by the compressed air supplied to the superheated steam supply line (20a). The compressed air is supplied from the superheated steam supply line (20a) downstream of the flow meter (29). The compressed air supply unit (30) is equipped with a compressor (31) for compressing air, a dryer (33) for drying compressed air, a pressure regulator (33) for controlling the pressure of compressed air, and a flow meter (37) for measuring the flow rate of compressed air. The compressor (31), dryer (33), pressure regulator (35), and flow meter (37) are positioned sequentially along the direction of flow on the compressed air supply line (30a) through which compressed air flows.

[0028] The compressor (31) compresses air to produce compressed air.

[0029] A dryer (33) is installed downstream of the compressor (31) on the compressed air supply line (30a) to dry the compressed air discharged from the compressor (31).

[0030] The pressure regulator (35) is installed downstream of the dryer (33) on the compressed air supply line (30a) to regulate the pressure of the compressed air flowing along the compressed air supply line (30a).

[0031] A flow meter (37) is installed downstream of the pressure regulator (35) on the compressed air supply line (30a) to measure the flow rate of compressed air that flows along the compressed air supply line (30a) and is supplied to the superheated steam supply line (20a). The compressed air supply unit (30) can regulate the flow rate of compressed air supplied to the superheated steam supply line (20a).

[0032] The compressed air supplied by the compressed air supply unit (30) is injected together with superheated steam through the injection nozzle (160 in FIG. 3) of the dry reactor (100). The compressed air supply unit (30) may not be provided, and this is also within the scope of the present invention.

[0033] The cyclone filter (52) captures particles containing SiO2 particles contained in the HF gas discharged from the dry reactor (100). In the cyclone filter (52), the unreacted SiF4 gas and superheated steam may further react to remove the SiF4 gas. In this embodiment, the temperature of the HF gas discharged from the dry reactor (100) and flowing into the cyclone filter (52) and the temperature of the HF gas discharged from the cyclone filter (52) are approximately 220°C.

[0034] The bag filter (54) captures powder components containing SiO2 particles contained in the HF gas discharged from the cyclone filter (52).

[0035] Particles containing SiO2 particles flowing together with HF gas are captured by the cyclone filter (52) and the bag filter (54), so that powder components containing SiO2 particles are not introduced into the condensation equipment (1000 of FIG. 1), and only gas containing HF gas can be introduced. The cyclone filter (52) and the bag filter (54) constitute a particle capture section.

[0036] The mixer (56) cools the HF gas that is discharged from the cyclone filter (52) and flows into the bag filter (54) by mixing it with the outside air. The mixer (56) is installed in the filter connection line (55) connecting the cyclone filter (52) and the bag filter (54). The flow rate of the outside air supplied to the mixer (56) can be measured and controlled by the flow meter (57). In the mixer (56), the HF gas at approximately 220°C is mixed with the outside air and cooled to approximately 170°C. The HF gas cooled to approximately 170°C passes through the bag filter (56) and is supplied to the condensation equipment (1000).

[0037] Now, with reference to FIGS. 2 to 4, the dry gas decomposition equipment (10) will be described in terms of operation. The SiF4 gas to be decomposed is introduced into the dry reactor (100) through the inlet (120) of the dry reactor (100) and flows downward along the passage (120) toward the outlet (150).

[0038] Superheated steam supplied by the superheated steam supply unit (20) is injected into the injection section (122) of the dry reactor (100) through each of the plurality of injection nozzles (160) provided in the dry reactor (100). The injection performance of the superheated steam in the dry reactor (100) is controlled by compressed air supplied by the compressed air supply unit (30).

[0039] SiF4 gas reacts with superheated steam sprayed in the spray section (122) of the dry reactor (100) to decompose, and silicon dioxide (SiO2) particles and hydrogen fluoride (HF) gas are produced. As the SiF4 gas and superheated steam pass through the contraction section (126), they form turbulence and are evenly mixed to form reactivity, and as they pass through the diffusion section (128), the flow diffuses to prevent the aggregation of particles.

[0040] Silicon dioxide (SiO2) particles and hydrogen fluoride (HF) gas that have passed through the diffusion section (128) are discharged through the outlet (150).

[0041] The HF gas discharged from the dry reactor (100) through the outlet (150) passes through the cyclone filter (52) and the bag filter (54) in sequence, and particles containing SiO2 particles flowing together with the HF gas are captured, and in the cyclone filter (52), the SiF4 gas and superheated steam react further.

[0042] FIGS. 5 and 6 illustrate the structure of a dry reactor according to another embodiment of the present invention. Referring to FIGS. 5 and 6, the dry reactor (200) comprises a reaction body (110) and a plurality of injection nozzles (260) coupled to the reaction body (110). The reaction body (110) is generally identical to the configuration of the reaction body (110) described in FIGS. 2 and 3. The injection direction of each of the plurality of injection nozzles (260) all faces the central axis (X) on the cross-section of the passage (120) and is generally perpendicular to the extension direction of the passage (120). The remaining configurations, excluding this, are generally identical to the configuration of the plurality of injection nozzles (160) described in FIGS. 2 and 3.

[0043] Referring to FIG. 1, the condensation equipment (1000) condenses the HF gas discharged from the dry gas decomposition equipment (10) to produce anhydrous hydrofluoric acid. FIG. 7 shows the configuration of the condensation equipment (1000) as a block diagram. Referring to FIG. 7, the condensation equipment (1000) comprises a gas flow fan (1001) that forms a gas flow pressure on a gas flow line through which HF gas flows, a first cooling unit (1100a) that cools the incoming HF gas, a second cooling unit (1200a) that further cools the HF gas discharged from the first cooling unit (1100a), a water supply unit (1300) that supplies water to the first cooling unit (1100a) and the second cooling unit (1200a), a first condenser (1400a) that condenses the HF gas discharged from the second cooling unit (1200a), a second condenser (1400b) that condenses the HF gas discharged from the first condenser (1400a), a first gas-liquid separator (1500) that separates a liquid component from the gas discharged from the second condenser (1400b), and a first It is equipped with an aqueous solution storage tank (1600a) in which an aqueous solution of hydrogen fluoride produced by condensing HF gas in a condenser (1400a) is stored, an anhydrous hydrofluoric acid storage tank (1600b) in which anhydrous hydrofluoric acid produced by condensing HF gas in a second condenser (1400b) is stored, and a second gas-liquid separator (1900) for separating liquid components from HF gas flowing into the first condenser (1400a).

[0044] The gas flow fan (1001) forms a gas flow pressure on the gas flow line through which HF gas flows. In this embodiment, the gas flow fan (1001) is described as being located downstream of the first gas-liquid separator (1500) on the gas flow line, but the present invention is not limited thereto. The gas flow fan (1001) may be located upstream of the first cooling section (1100a), or downstream of the first cooling section (1100a) and upstream of the second cooling section (1200a), and this is also within the scope of the present invention. By operating the gas flow fan (1001), the HF gas passes through the first cooling section (1100a), the second cooling section (1200a), the second gas-liquid separator (1900), the first condenser (1400a), the second condenser (1400b), and the first gas-liquid separator (1500) in sequence.

[0045] The first cooling unit (1100a) primarily cools the incoming HF gas. The first cooling unit (1100a) is equipped with a first microbubble device (1100) that generates HF gas into microbubbles in a first liquid, a first liquid storage tank (1192) in which the first liquid is stored, and a first liquid heat exchanger (1198) that cools the first liquid supplied in circulation from the first liquid storage tank (1192) to the first microbubble device (1100).

[0046] The first microbubble device (1100) cools HF gas by generating microbubbles in a first liquid containing water. Referring to FIG. 8, which specifically illustrates the structure of the first microbubble device (1100), the first microbubble device (1100) comprises a first inlet (1110) into which HF gas and a first liquid (L1) circulatingly supplied from a first liquid storage tank (1192 in FIG. 7) are introduced, a first bubble generating part (1130) in which HF gas generates microbubbles in the first liquid (L1), and a first connecting passage (1180) connecting the first inlet (1110) and the first bubble generating part (1130). The first microbubble device (1100) also serves to remove residual SiO2 particles contained in the HF gas.

[0047] HF gas, a first liquid (L1) circulating from a first liquid storage tank (1192 in FIG. 7), and industrial water supplied by a water supply unit (1300) are introduced into the first introduction unit (1110). The first introduction unit (1110) provides a first introduction space (1111) formed inside. The first introduction space (1111) is connected to the first bubble generating unit (1130) by a first passage unit (1180). A first intake port (1113) is located at the top of the first introduction space (1111), and a first introduction space drain (1115) is located at the bottom of the first introduction space (1111). HF gas discharged from a particle collection device (50 in FIG. 7) is introduced into the first introduction space (1111) through the first intake port (1113). In this embodiment, the temperature of the HF gas flowing into the first introduction space (1111) is approximately 170°C. Drainage is performed through the first introduction space drain (1115). The first introduction space (1111) is connected to the first connecting passage (1180) at a position lower than the first intake port (1113) and higher than the first introduction space drain (1115).

[0048] Between the first intake port (1113) and the first intake port (1115) in the first introduction space (1111), a first water tank (1117), a first A water pipe (1119), a first A diffusion plate (1121), a first B water pipe (1123), a first B diffusion plate (1125), a first liquid introduction supply means (1126), and a first industrial water supply means (1126a) are installed.

[0049] The first tank (1117) is located adjacent to the bottom of the first intake port (1113) in the first introduction space (1111). The first HF aqueous solution (L1) circulatingly supplied from the first liquid storage tank (1192 in FIG. 7) is temporarily stored in the first tank (1117). The first liquid (L1) overflowing from the first tank (1117) flows downward through the first A water pipe (1119).

[0050] The first A water pipe (1119) is located below the first water tank (1117) in the first introduction space (1111). The first A water pipe (1119) has a shape that narrows as it goes down, and a first A water pipe outlet (1120) is formed at the bottom of the first A water pipe (1119) to discharge the first liquid (L1) and HF gas downward. As the HF gas and the first liquid (L1) flow downward along the first A water pipe (1119) toward the first A water pipe outlet (1120), the contact area between the HF gas and the first liquid (L1) increases.

[0051] The first A diffuser plate (1121) is located below the first A water pipe outlet (1120) in the first introduction space (1111). The first A diffuser plate (1121) is inclined downward radially outward from the center to widely disperse the first liquid (L1) discharged from the first A water pipe outlet (1120) outward.

[0052] The first B water pipe (1123) is located below the first A diffusion plate (1121) in the first introduction space (1111). The first B water pipe (1123) has a shape that narrows as it goes down, and a first B water pipe outlet (1124) is formed at the bottom of the first B water pipe (1123) to discharge the first liquid (L1) and HF gas downward. As the HF gas and the first liquid (L1) flow downward along the first B water pipe (1123) toward the first B water pipe outlet (1124), the contact area between the HF gas and the first liquid (L1) increases.

[0053] The first B diffusion plate (1125) is located below the first B water pipe outlet (1124) in the first introduction space (1111). The first B diffusion plate (1125) is inclined downward radially outward from the center to widely disperse the first liquid (L1) discharged from the first B water pipe outlet (1124) outward.

[0054] The first liquid introduction supply means (1126) circulates and supplies the first liquid (L1) from the first liquid storage tank (1192 in FIG. 7) to the first introduction space (1111). The first liquid introduction supply means (1126) is positioned above the first tank (1117) and supplies the first liquid (L1) to the first tank (1117).

[0055] The first industrial water supply means (1126a) supplies industrial water to the first introduction space (1111). In this embodiment, the first industrial water supply means (1126a) is described as being located above the first liquid introduction supply means (1126).

[0056] The first bubble generating unit (1130) supplies HF gas in the form of microbubbles to the first liquid (L1) to cool the temperature of the HF gas. The first bubble generating unit (1130) provides a first bubble generating space (1131) inside. The first bubble generating space (1131) is connected to the first introduction space (1111) through the first connecting passage (1180). A first exhaust port (1132) is located at the top of the first bubble generating space (1131), and a first reaction space drain (1133) is located at the bottom of the first bubble generating space (1131). Gas inside the first bubble generating space (1131) is discharged through the first exhaust port (1132). Drainage is performed through the first reaction space drain (1133). The first bubble generation space (1131) is connected to the first connecting passage (1180) at a position lower than the first exhaust port (1132) and higher than the first reaction space drain (1133).

[0057] The first bubble generation space (1131) is provided with a first bubble generation unit (1160) positioned between the first connecting passage (1180) and the first exhaust port (1132). HF gas introduced into the first bubble generation space (1131) through the first connecting passage (1180) rises upward and passes through the first bubble generation unit (1160).

[0058] The first bubble generation unit (1160) comprises a first bottom plate (1162), a first atomizing part (1164) installed on the first bottom plate (1162), a first water level control part (1170), and a first liquid reaction part supply means (1177).

[0059] The first bottom plate (1162) is plate-shaped and is installed generally horizontally in the internal space of the first bubble generating unit (1160) and is located above the first connecting passage (1180). The internal space of the first bubble generating unit (1160) is separated into a first lower space (1161) and a first upper space (1163) with the first bottom plate (1162) in between, and the first liquid (L1) supplied from the first liquid storage tank (1192 in FIG. 7) is stored in the first upper space (1163). A first atomizing part (1164) is installed on the first bottom plate (1162).

[0060] The first atomizing unit (1164) injects HF gas present in the first lower space (1161) into the first upper space (1163) where the first liquid (L1) is stored. The HF gas injected by the first atomizing unit (1164) forms microbubbles (B1) within the first liquid (L1). The first atomizing unit (1164) is equipped with a first gas injection nozzle (1165) that injects HF gas into the first upper space (1163), and a first impact plate (1166) located at the end of the first gas injection nozzle (1165). The first atomizing unit (1164) bubbles the HF gas into micro / nano sizes. The HF gas can be cooled and partially dissolved by the microbubbles (B1) formed by the first atomizing unit (1166).

[0061] The first gas injection nozzle (1165) is formed by protruding upward from the first bottom plate (1162) and is located in the first upper space (1163). HF gas from the first lower space (1161) is injected upward into the first upper space (1163) by the first gas injection nozzle (1165). As illustrated, the first gas injection nozzle (1165) has a section in which the internal passage narrows toward the end where the injection port is formed, so that the gas flow along the first gas injection nozzle (1165) and the velocity of the gas increases. A first impact plate (1166) is located adjacent to the end of the first gas injection nozzle (1165).

[0062] The first impact plate (1166) is positioned in the first upper space (1163) adjacent to the end of the first gas injection nozzle (1165). The HF gas injected from the first gas injection nozzle (1165) strongly collides with the first impact plate (1166), which is submerged in the first liquid (L1), to form a microbubble (B1). In this embodiment, the first impact plate (1166) is described as having a two-stage structure in which the first lower impact plate (1167) and the first upper impact plate (1168) are arranged sequentially along the height direction as shown in the illustration; however, the present invention is not limited thereto, and a one-stage structure or a structure of three or more stages is also within the scope of the present invention. In the case of a multi-stage structure, it is preferable that the first upper impact plate (1168) located above is larger so as to cover the entirety of the first lower impact plate (1167) located below, and that at least one first passage (1169) is formed between the first upper impact plates (1168).

[0063] The first water level control unit (1170) is located on the side of the first upper space (1163) and controls the water level of the first liquid (L1) through an overflow in the first upper space (1163). The first liquid (1170) is provided with a first water level control tank (1172) that communicates with the first upper space (1163) through a first water level control opening (1171) formed on the side wall of the first upper space (1163). The first water level control opening (1171) is located in the first upper space (1163) at a height corresponding to the water level control height of the first liquid (L1). The first liquid (L1) overflowed from the first upper space (1163) is stored in the first water level control tank (1172). The first liquid (L1) stored in the first water level control tank (1172) is discharged and supplied to the first liquid storage tank (1192 in FIG. 7). The first liquid discharged from the first water level control tank (1172) and supplied to the first liquid storage tank (1192 in FIG. 7) contains microbubbles.

[0064] The first liquid reaction unit supply means (1177) supplies the first liquid (L1) supplied from the first liquid storage tank (1192 in FIG. 7) to the first upper space (1163).

[0065] In the above embodiment, the first bubble generating part (1130) is described as having one first bubble generating unit (1160), but alternatively, a plurality of units may be arranged continuously along the height direction, and this is also within the scope of the present invention.

[0066] The first liquid (L1) discharged through the first introduction space drain (1115) and the first reaction space drain (1133), respectively, is supplied to the first liquid storage tank (1192 in FIG. 7).

[0067] The first connecting passage (1180) connects the first introduction space (1111) of the first introduction section (1110) with the first bubble generation space (1131) of the first bubble generation section (1130). The first connecting passage (1180) is located below the first intake port (1113) and the first exhaust port (1132), and above the first introduction space drain (1115) and the first reaction space drain (1133).

[0068] Referring to FIGS. 7 and 8, the first liquid storage tank (1192) stores a first liquid (L1) that is circulated and supplied to the first microbubble device (1100). The first liquid (L1) that is drained from the first microbubble device (1100) by gravity is stored in the first liquid storage tank (1192), and the first liquid (L1) stored in the first liquid storage tank (1192) is supplied to the first microbubble device (1100) by a pump. The first liquid (L1) stored in the first liquid storage tank (1192) contains microbubbles discharged from the first microbubble device (1100). The first liquid storage tank (1192) may be coupled to the first microbubble device (1100) and formed integrally. The first liquid (L1) discharged from the first liquid storage tank (1192) is supplied to the first microbubble device (1100) via the first liquid heat exchanger (1198). The first liquid (L1) of the first liquid storage tank (1192) is discarded.

[0069] The first liquid heat exchanger (1198) cools the first liquid (L1) that is circulated from the first liquid storage tank (1192) to the first microbubble device (1100) by exchanging heat with cold water.

[0070] Now, referring to FIGS. 8 and 9, the operation process of the first cooling unit (1100a) is described as follows. FIG. 9 shows the state of the first microbubble device (1100) before the cooling process of the first cooling unit (1100a) is performed, in which the gas flow fan (1001 in FIG. 7) is not operating. Referring to FIG. 9, the water level of the first liquid (L1) in the first bubble generation unit (1160) of the first microbubble device (1100) is located below the end where the nozzle of the first gas injection nozzle (1165) is located, so that the first liquid (L1) does not leak downward through the first gas injection nozzle (1165).

[0071] When the gas flow fan (1001 in FIG. 7) is operated in the state shown in FIG. 9, HF gas from the first lower space (1161) is injected into the first upper space (1163) through the first gas injection nozzle (1165) in the first microbubble device (1100). In this state, when the first liquid (L1) is supplied to the first microbubble device (1100), as shown in FIG. 8, the water level of the first liquid (L1) in the first upper space (1163) of the first microbubble device (1100) rises sufficiently high to form microbubbles (B1). The water level of the first liquid (L1) in the first upper space (1163) of the first microbubble device (1100) is appropriately maintained by the first water level control unit (1170).

[0072] Referring to FIG. 7, the second cooling unit (1200a) secondarily additionally cools the HF gas discharged from the first microbubble device (1100) of the first cooling unit (1100a). The HF gas discharged from the second cooling unit (1200) is cooled to 120 to 140°C and supplied to the first condenser (1400a).

[0073] The second cooling unit (1100a) comprises a second microbubble device (1200) that generates HF gas into microbubbles in the second liquid, a second liquid storage tank (1292) in which the second liquid is stored, and a second liquid heat exchanger (1298) that cools the second liquid supplied in circulation from the second liquid storage tank (1292) to the second microbubble device (1200).

[0074] The second microbubble device (1200) cools HF gas by generating microbubbles in a second liquid containing water. Referring to FIG. 10, which specifically illustrates the structure of the second microbubble device (1200), the second microbubble device (1200) comprises a second inlet (1210) into which HF gas and a second liquid (L2) circulatingly supplied from a second liquid storage tank (1292 in FIG. 7) are introduced, a second bubble generating part (1230) in which HF gas generates microbubbles in the second liquid (L2), and a second connecting passage (1280) connecting the second inlet (1210) and the second bubble generating part (1230). The second microbubble device (1200) also serves to remove residual SiO2 particles contained in the HF gas.

[0075] HF gas discharged from the first microbubble device (1100 in FIG. 7), the second liquid (L2) circulated from the second liquid storage tank (1292 in FIG. 7), and industrial water supplied by the water supply unit (1300) are introduced into the second introduction unit (1210). The second introduction unit (1110) provides a second introduction space (1211) formed inside. The second introduction space (1211) is connected to the second bubble generation unit (1230) by the second passage unit (1280). A second intake port (1213) is located at the top of the second introduction space (1211), and a second introduction space drain (1215) is located at the bottom of the second introduction space (1211). HF gas discharged from the first microbubble device (1100 in FIG. 7) through the second intake port (1213) flows into the second introduction space (1211). Drainage is performed through the second introduction space drain port (1215). The second introduction space (1211) is connected to the second connecting passage section (1280) at a position lower than the second intake port (1213) and higher than the second introduction space drain port (1215).

[0076] Between the second intake port (1213) and the second intake port (1215) in the second introduction space (1211), a second water tank (1217), a second A water pipe (1219), a second A diffusion plate (1121), a second B water pipe (1223), a second B diffusion plate (1225), a second liquid introduction supply means (1226), and a second industrial water supply means (1226a) are installed.

[0077] The second tank (1217) is located adjacent to the lower part of the second intake port (1213) in the second introduction space (1211). The second liquid (L2) circulating from the second storage tank (1292 in FIG. 2) is temporarily stored in the second tank (1217). The second liquid (L2) overflowing from the second tank (1217) flows downward through the second A water pipe (1219).

[0078] The second A water pipe (1219) is located below the second tank (1217) in the second introduction space (1211). The second A water pipe (1219) has a shape that narrows as it goes down, and a second A water pipe outlet (1220) is formed at the bottom of the second A water pipe (1219) to discharge the second liquid (L2) and HF gas downward. As the HF gas and the second liquid (L2) flow downward along the second A water pipe (1219) toward the second A water pipe outlet (1220), the contact area between the HF gas and the liquid (L2) increases.

[0079] The second A diffuser plate (1221) is located below the second A water pipe outlet (1220) in the second introduction space (1211). The second A diffuser plate (1221) is inclined downward radially outward from the center to widely disperse the second liquid (L2) discharged from the second A water pipe outlet (1220) outward.

[0080] The second B water pipe (1223) is located below the second A diffusion plate (1221) in the second introduction space (1211). The second B water pipe (1223) has a shape that narrows as it goes down, and a second B water pipe outlet (1224) is formed at the bottom of the second B water pipe (1223) to discharge the second liquid (L2) and HF gas downward. As the HF gas and the second liquid (L2) flow downward along the second B water pipe (1223) toward the second B water pipe outlet (1224), the contact area between the HF gas and the second liquid (L2) increases.

[0081] The second B diffusion plate (1225) is located below the second B water pipe outlet (1224) in the second introduction space (1211). The second B diffusion plate (1225) is inclined downward radially outward from the center to widely disperse the second liquid (L2) discharged from the second B water pipe outlet (1224) outward.

[0082] The second liquid introduction supply means (1226) circulates and supplies the second liquid (L2) from the second storage tank (1292 in FIG. 7) to the second introduction space (1211). The second liquid introduction supply means (1226) is positioned above the second tank (1217) and supplies the second liquid (L2) to the second tank (1217).

[0083] The second industrial water supply means (1226a) supplies industrial water to the second introduction space (1211). In this embodiment, the second industrial water supply means (1226a) is described as being located above the second liquid introduction supply means (1226).

[0084] The second bubble generating unit (1230) supplies HF gas in the form of microbubbles to the second liquid (L2) to cool the temperature of the HF gas. The second bubble generating unit (1230) provides a second bubble generating space (1231) inside. The second bubble generating space (1231) is connected to the second introduction space (1211) through the second connecting passage (1280). A second exhaust port (1232) is located at the top of the second bubble generating space (1231), and a second reaction space drain (1233) is located at the bottom of the second bubble generating space (1231). Gas inside the second bubble generating space (1231) is discharged through the second exhaust port (1232). Drainage is performed through the second reaction space drain (1233). The second bubble generation space (1231) is connected to the second connecting passage (1280) at a position lower than the second exhaust port (1232) and higher than the second reaction space drain (1233).

[0085] The second bubble generation space (1231) is provided with a second bubble generation unit (1240) positioned between the second connecting passage (1280) and the second exhaust port (1232). HF gas introduced into the second bubble generation space (1231) through the second connecting passage (1280) rises upward and passes through the second bubble generation unit (1240).

[0086] The second bubble generation unit (1240) comprises a second bottom plate (1242), a second atomizing part (1244) installed on the second bottom plate (1242), a second water level control part (1250), and a second liquid reaction part supply means (1257).

[0087] The second bottom plate (1242) is plate-shaped and is installed generally horizontally within the internal space of the second bubble generating unit (1240), and is positioned above the second connecting passage (1280). The internal space of the second bubble generating unit (1240) is separated into a second lower space (1241) and a second upper space (1243) with the second bottom plate (1242) in between, and the second liquid (L2) supplied from the second liquid storage tank (1292 in FIG. 7) is stored in the second upper space (1243). A second atomizing part (1244) is installed on the second bottom plate (1242).

[0088] The second atomizing unit (1244) injects HF gas present in the second lower space (1241) into the second upper space (1243) where the second liquid (L2) is stored. The HF gas injected by the second atomizing unit (1244) forms microbubbles (B2) within the second liquid (L2). The second atomizing unit (1244) is equipped with a second gas injection nozzle (1245) that injects HF gas into the second upper space (1243), and a second impact plate (1246) located at the end of the second gas injection nozzle (1245). The second atomizing unit (1264) bubbles the HF gas into micro / nano sizes. The HF gas can be cooled and partially dissolved by the microbubbles (B2) formed by the second atomizing unit (1246).

[0089] The second gas injection nozzle (1245) is formed by protruding upward from the second bottom plate (1242) and is located in the second upper space (1243). HF gas from the second lower space (1241) is injected upward into the second upper space (1243) by the second gas injection nozzle (1245). As illustrated, the second gas injection nozzle (1245) has a section in which the internal passage narrows toward the end where the injection port is formed, so that the gas flow along the second gas injection nozzle (1245) and the velocity of the gas increases. A second impact plate (1246) is located adjacent to the end of the second gas injection nozzle (1245).

[0090] The second impact plate (1246) is positioned in the second upper space (1243) adjacent to the end of the second gas injection nozzle (1245). The HF gas injected from the second gas injection nozzle (1245) strongly collides with the second impact plate (1246), which is submerged in the second liquid (L2), to form a microbubble (B2). In this embodiment, the second impact plate (1246) is described as having a two-stage structure in which the second lower impact plate (1247) and the second upper impact plate (1248) are arranged sequentially along the height direction as shown in the illustration; however, the present invention is not limited thereto, and a one-stage structure or a structure of three or more stages is also within the scope of the present invention. In the case of a multi-stage structure, it is preferable that the second upper impact plate (1248) located above is larger so as to cover the entire second lower impact plate (1247) located below, and that at least one second passage (1249) is formed between the second upper impact plates (1248).

[0091] The second water level control unit (1250) is located on the side of the second upper space (1243) and controls the water level of the second liquid (L2) through an overflow from the second upper space (1243). The second water level control unit (1250) is provided with a second water level control tank (1252) that communicates with the second upper space (1243) through a second water level control opening (1271) formed on the side wall of the second upper space (1243). The second water level control opening (1251) is located in the second upper space (1243) at a height corresponding to the water level control height of the second body (L2). The second liquid (L2) that overflows from the second upper space (1243) is stored in the second water level control tank (1252). The second liquid (L2) stored in the second water level control tank (1252) is discharged and supplied to the second liquid storage tank (1292 in FIG. 7). The solution discharged from the second water level control tank (1272) and supplied to the second liquid storage tank (1292 in FIG. 7) contains microbubbles.

[0092] The second liquid reaction unit supply means (1257) supplies the second liquid (L2) supplied from the second liquid storage tank (1292 in FIG. 7) to the second upper space (1243).

[0093] In the above embodiment, the second bubble generating unit (1230) is described as having one second bubble generating unit (1240), but alternatively, a plurality of them may be arranged continuously along the height direction, and this is also within the scope of the present invention.

[0094] The second liquid (L2) discharged through the second introduction space drain (1215) and the second reaction space drain (1233), respectively, is supplied to the second liquid storage tank (1292 in FIG. 7).

[0095] The second connecting passage (1280) connects the second introduction space (1211) of the second introduction section (1210) with the second bubble generation space (1231) of the second bubble generation section (1230). The second connecting passage (1280) is located below the second intake port (1213) and the second exhaust port (1232), and above the second introduction space drain (1215) and the second reaction space drain (1233).

[0096] Referring to FIGS. 7 and FIGS. 10, the second liquid storage tank (1292) stores the second liquid (L2) that is circulated and supplied to the second microbubble device (1200). The second liquid (L2) that is drained from the second microbubble device (1200) by gravity is stored in the second liquid storage tank (1292), and the second liquid (L2) stored in the second liquid storage tank (1292) is supplied to the second microbubble device (1200) by a pump. The second liquid (L2) stored in the second liquid storage tank (1292) contains the discharged microbubbles generated from the second microbubble device (1200). The second liquid storage tank (1292) may be coupled to the second microbubble device (1200) and formed integrally. The second liquid (L2) discharged from the second liquid storage tank (1292) is supplied to the second microbubble device (1200) via the second liquid heat exchanger (1298).

[0097] The second liquid heat exchanger (1298) cools the second liquid (L2) that is circulated from the second liquid storage tank (1292) to the second microbubble device (1200) by exchanging heat with cold water.

[0098] In this embodiment, the temperature of the HF gas discharged through the second exhaust port (1232) is 120 to 140°C. That is, in this embodiment, the HF gas at approximately 170°C is cooled to 120 to 140°C by the first cooling unit (1100a) and the second cooling unit (1200a).

[0099] Now, referring to FIGS. 10 and 11, the operation process of the second cooling unit (1200a) is described as follows. FIG. 11 shows the state of the second microbubble device (1200) before the cooling process of the second cooling unit (1200a) is performed, in which the gas flow fan (1001 of FIG. 7) is not operating. Referring to FIG. 11, the water level of the second liquid (L2) in the second bubble generation unit (1240) of the second microbubble device (1200) is located below the end where the nozzle of the second gas injection nozzle (1245) is located, so that the second liquid (L2) does not leak downward through the second gas injection nozzle (1245). When the second microbubble device (1200) is in the state of FIG. 11, the first microbubble device (1100) is in the state of FIG. 9, and when the gas flow fan (1001 of FIG. 7) is operated, HF gas flows to pass through the first microbubble device (1100) and the first microbubble device (1200) in sequence.

[0100] When the gas flow fan (1001 in FIG. 7) is operated in the state shown in FIG. 11, HF gas from the second lower space (1241) is injected into the second upper space (1243) through the second gas injection nozzle (1245) in the second microbubble device (1200). In this state, when the second liquid (L2) is supplied to the second microbubble device (1200), as shown in FIG. 10, the water level of the second liquid (L2) in the second upper space (1243) of the second microbubble device (1200) rises sufficiently high to form microbubbles (B2). The water level of the second liquid (L2) in the second upper space (1243) of the second microbubble device (1200) is appropriately maintained by the second water level control unit (1250).

[0101] The first cooling unit (1100a) and the second cooling unit (1200a) serve to reduce the load of the first condenser (1400a) and the second condenser (1400b).

[0102] In this embodiment, the condensation equipment (1000) is described as having two cooling units, a first cooling unit (1100a) and a second cooling unit (1200a), connected in series, but the present invention is not limited thereto. The condensation equipment (1000) may be composed of only one cooling unit, and this also falls within the scope of the present invention.

[0103] Referring to FIG. 7, the water supply unit (1300) supplies industrial water to the first microbubble device (1100) of the first cooling unit (1100a) and the second microbubble device (1200) of the second cooling unit (1200a). The water supply unit (1300) is equipped with a water tank (1320) in which industrial water is stored, and a pump (1325) that flows the industrial water stored in the water tank (1320) to the first microbubble device (1100) and the second microbubble device (1200). The industrial water supplied by the water supply unit (1300) is supplied to the first introduction space (1111) of the first microbubble device (1100) through the first industrial water supply means (1126a) provided in the first microbubble device (1100), and is supplied to the second introduction space (1211) of the second microbubble device (1200) through the second industrial water supply means (1226a) provided in the second microbubble device (1200).

[0104] The first condenser (1400a) condenses HF gas at a temperature of 120 to 140°C discharged from the second cooling unit (1200a) to produce an HF aqueous solution. In this embodiment, the first condenser (1400a) condenses the HF gas by heat-exchanging it with cold water at a temperature of about 10°C. The temperature of the HF gas discharged to the first condenser (1400a) is 60 to 70°C. The HF aqueous solution produced in the first condenser (1400a) is stored in the aqueous solution storage unit (1600a). In this embodiment, a conventional shell and tube heat exchanger is described as being used as the first condenser (1400a). In a shell and tube heat exchanger, cooling water passes through the shell, and HF gas passes through the tube. Although the shell and tube heat exchanger is described as being used as the first condenser (1400a) in this embodiment, the present invention is not limited thereto. For the first condenser (1400a), a condenser of a conventional configuration other than a shell-and-tube heat exchanger may be used, and this is also within the scope of the present invention.

[0105] The second condenser (1400b) condenses HF gas at a temperature of 60 to 70°C discharged from the first condenser (1400a) to produce anhydrous hydrofluoric acid. In this embodiment, the second condenser (1400b) condenses the HF gas by heat-exchanging it with cold water at a temperature of about 10°C. The anhydrous hydrofluoric acid produced in the second condenser (1400b) is stored in an anhydrous hydrofluoric acid storage tank (1600b). Although the second condenser (1400b) is described as being used as a shell-and-tube heat exchanger in this embodiment, the present invention is not limited thereto. A condenser of a conventional configuration other than a shell-and-tube heat exchanger may be used as the second condenser (1400b), and this is also within the scope of the present invention.

[0106] The first gas-liquid separator (1500) separates the liquid component from the gas discharged from the second condenser (1400b). In this embodiment, a cyclone filter is described as being used as the first gas-liquid separator (1500). The liquid component separated in the gas-liquid separator (1500) is supplied to and stored in an anhydrous hydrofluoric acid storage tank (1600b).

[0107] The aqueous solution storage tank (1600a) stores the HF aqueous solution generated in the first condenser (1400a).

[0108] Anhydrous hydrofluoric acid generated in the second condenser (1400b) is stored in the anhydrous hydrofluoric acid storage tank (1600b). Anhydrous hydrofluoric acid storage tank (1600b) may also be supplied with and stored an HF aqueous solution stored in the aqueous solution storage tank (1600a), but in this case, the HF aqueous solution stored in the aqueous solution storage tank (1600a) may not be supplied to the anhydrous hydrofluoric acid storage tank (1600b) and may be utilized separately.

[0109] The second gas-liquid separator (1900) separates the liquid component from the HF gas discharged from the second microbubble device (1200) and introduced into the first condenser (1400a). In this embodiment, a cyclone filter is described as being used as the second gas-liquid separator (1900).

[0110] Although the present invention has been described through the above embodiments, the present invention is not limited thereto. The above embodiments may be modified or changed without departing from the spirit and scope of the present invention, and those skilled in the art will understand that such modifications and changes are also within the scope of the present invention. Explanation of the symbols

[0111] 1: Silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility 10: Dry gas decomposition equipment 20: Superheated steam supply unit 30: Compressed air supply unit 52: Cyclone filter 100: Dry reactor 110: Reaction body 120: Passage 122: Spray section 124: Neck section 126: Contraction section 128: Diffusion zone 140: Inlet 150: Outlet 160: Spray nozzle 162: Nozzle nozzle 200: Dry reactor 260: Nozzle nozzle 1000: Condensation equipment 1001: Gas flow fan 1100: First microbubble device 1130: 1st Bubble Generation Section 1160: 1st Bubble Generation Unit 1162: 1st base plate 1164: 1st atomizing section 1165: 1st gas injection nozzle 1166: 1st impact plate 1192: First liquid storage tank 1200: Second microbubble device 1230: 2nd Bubble Generation Unit 1240: 2nd Bubble Generation Unit 1242: Second base plate 1244: Second atomizing section 1245: Second gas injection nozzle 1246: Second impact plate 1292: Second liquid storage tank 1298: Second liquid heat exchanger 1300: Water supply unit 1400a: First condenser 1400b: Second condenser

Claims

Claim 1 A dry gas decomposition apparatus for decomposing silicon tetrafluoride gas to produce hydrogen fluoride gas; and a condensation apparatus for condensing the hydrogen fluoride gas to produce anhydrous hydrofluoric acid, wherein the dry gas decomposition apparatus comprises a dry reactor in which the silicon tetrafluoride gas reacts with superheated steam to decompose and the hydrogen fluoride gas and silicon dioxide particles are produced, and the condensation apparatus comprises a condenser for condensing the hydrogen fluoride gas and a cooling unit for cooling the hydrogen fluoride gas before the hydrogen fluoride gas is supplied to the condenser, and the cooling unit comprises a microbubble device for supplying the hydrogen fluoride gas to water in the form of microbubbles. Claim 2 In claim 1, the dry reactor comprises a reaction body providing a passage through which the silicon tetrafluoride gas flows, and a spray nozzle coupled to the reaction body, wherein the passage extends along the longitudinal direction and comprises a spray section in which a nozzle nozzle of the spray nozzle is located, and the superheated steam is sprayed into the spray section through the nozzle nozzle, and a dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility. Claim 3 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 2, wherein the reaction body has an outlet through which gas is discharged from the passage, and the passage further comprises a neck section located between the injection section and the outlet and having a cross-sectional area smaller than that of the injection section, a contraction section located between the injection section and the neck section and having a cross-sectional area that decreases as it approaches the neck section, and a diffusion section located between the neck section and the outlet and having a cross-sectional area that increases as it moves away from the neck section. Claim 4 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 3, wherein the longitudinal direction of the inner circumference of the contraction section forms an angle of 20 to 25° with the central axis of the passage. Claim 5 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 4, wherein the longitudinal direction of the inner circumference of the diffusion section forms an angle of 5 to 7° with the central axis of the passage. Claim 6 In claim 2, the injection nozzles are a plurality of dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility. Claim 7 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 6, wherein the nozzle nozzles of each of the plurality of injection nozzles are arranged sequentially along the circumferential direction of the passage. Claim 8 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 7, wherein the injection direction of each of the plurality of injection nozzles is formed such that they all deviate from the central axis of the passage in the same direction on the cross-section of the passage. Claim 9 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 7, wherein at least one of the plurality of injection nozzles has an injection direction facing downstream. Claim 10 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 1, wherein the operating temperature of the dry reactor is 180 to 220°C. Claim 11 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 2, wherein the dry gas decomposition equipment further comprises a compressed air supply unit that supplies compressed air to superheated steam supplied to the injection nozzle. Claim 12 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 2, wherein the dry reactor further comprises a heater for heating the reaction body. Claim 13 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 1, wherein the condensation equipment further comprises a gas flow fan that generates flow pressure to cause the hydrogen fluoride gas to pass through the microbubble device, and the microbubble device comprises a bubble generation unit that forms the hydrogen fluoride gas into microbubbles in a liquid. Claim 14 In claim 13, the bubble generating unit comprises a bottom plate dividing an internal space into a lower space and an upper space in which the liquid is stored, a gas injection nozzle that sprays the hydrogen fluoride gas flowing into the lower space upward into the upper space, and a collision plate disposed above the gas injection nozzle to collide with the hydrogen fluoride gas sprayed from the gas injection nozzle, wherein when the gas flow fan starts operating while the liquid level in the upper space is lower than the nozzle of the gas injection nozzle, the hydrogen fluoride gas in the lower space is sprayed into the upper space, and the liquid is additionally circulated and supplied to the upper space so that the liquid level in the upper space rises, and when the collision plate in the upper space is submerged by the liquid, the hydrogen fluoride gas sprayed from the gas injection nozzle collides with the collision plate to form the microbubbles within the liquid, a dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility. Claim 15 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 1, wherein a plurality of cooling units are connected in series. Claim 16 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 1, wherein a plurality of condensers are connected in series to condense the hydrogen fluoride gas in stages. Claim 17 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 1, wherein the dry gas decomposition equipment further comprises a cyclone filter installed upstream of the condensation equipment for capturing silicon dioxide particles discharged together with the hydrogen fluoride gas from the dry reactor. Claim 18 A dry silicon tetrafluoride gas removal and anhydrous hydrofluoric acid production facility according to claim 17, wherein the hydrogen fluoride gas discharged from the cyclone filter is mixed with outside air and cooled.

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