Ultrasonic wave-based decomposition device for persistent substances and decomposition method

Abstract

An apparatus for decomposing persistent substances using ultrasound according to an embodiment of the present invention may include a sample inlet portion into which a sample containing persistent substances is introduced, a sample circulation portion connected to the sample inlet portion and having a circulation space in which the sample moved through the sample inlet portion is circulated, and an ultrasonic vibration portion surrounding at least a portion of the sample circulation portion so as to be spaced apart from an outer surface of the sample circulation portion, generating ultrasonic waves and applying them to the sample circulating within the sample circulation portion, thereby decomposing the persistent substances in the sample.

Description

[Technical Field]

[0001] The present invention relates to an ultrasonic decomposition device and method for decomposing persistent substances, and more particularly to an ultrasonic decomposition device and method for decomposing persistent substances, which can directly decompose the persistent substances in a sample circulation section with high decomposition performance by directly applying ultrasonic waves to a sample containing the persistent substances, such as perfluorinated compounds, and which has a simple structure and can be easily mass-produced. [Background technology]

[0002] Recently, there has been serious discussion about the harmful effects of PFAS (Poly- and Per-fluoroalkyl Substances), an environmental pollutant known as "forever chemicals" because it cannot be naturally decomposed.

[0003] Perfluorinated compounds are substances that combine carbon and fluorine, and are a type of environmental hormone that affects the ecosystem and human hormones. These perfluorinated compounds are used in fluororesin coatings (for pots and pans), packaging, and waterproof materials due to their heat-resistant and water- and oil-resistant properties. However, they are highly persistent and accumulative, and are found in the human environment.

[0004] Such perfluorinated compounds cause problems such as carcinogenicity, developmental toxicity, and reproductive toxicity. Furthermore, conventional techniques for removing perfluorinated compounds have limitations, and there are also limitations to the mass production of decomposition devices.

[0005] Conventional technology for removing perfluorinated compounds includes nanofiltration-electrochemical cathode technology. Although attempts have been made to remove PFHxA-contaminated water, this method is limited to a scale of less than 1 L, making it unsuitable for practical use on-site.

[0006] On the other hand, while granular activated carbon technology can significantly remove PFOS, there is a problem in that the activated carbon used for removal cannot be safely and appropriately disposed of.

[0007] Alternatively, there is the nanofiltration-photocatalytic oxidation-ultrafiltration method, which may be able to purify contaminated water on-site, but this has the cumbersome problem of requiring additional measures to remove any remaining PFOA, such as recycling the final wastewater.

[0008] That is, although there are various conventional techniques for removing perfluorinated compounds, there are practically no direct decomposition and mass production techniques.

[0009] Therefore, there is a need to develop a decomposition device and method for directly removing perfluorinated compounds. Summary of the Invention [Problem to be solved by the invention]

[0010] An embodiment of the present invention provides an ultrasonic decomposition device and method for decomposing persistent substances, which can directly decompose the persistent substances in a sample circulation section with high decomposition performance by directly applying ultrasonic waves to a sample containing persistent substances such as perfluorinated compounds, and which can be easily mass-produced because the device structure is not complicated.

[0011] The problems to be solved by the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0012] An apparatus for decomposing persistent substances using ultrasound according to an embodiment of the present invention may include a sample inlet portion into which a sample containing persistent substances is introduced, a sample circulation portion connected to the sample inlet portion and having a circulation space in which the sample moved through the sample inlet portion is circulated, and an ultrasonic vibration portion surrounding at least a portion of the sample circulation portion so as to be spaced apart from an outer surface of the sample circulation portion, generating ultrasonic waves and applying the ultrasonic waves to the sample circulating within the sample circulation portion to decompose the persistent substances in the sample.

[0013] In addition, the decomposition device according to an embodiment of the present invention may further include a sample outlet portion provided on one side of the sample circulation portion so as to face the sample inlet portion and through which the sample containing the persistent substances decomposed by the ultrasonic vibration portion is discharged from the sample circulation portion.

[0014] In addition, the decomposition device according to an embodiment of the present invention may further include a cooling section that is arranged to pass through the center of the sample inlet section, the sample circulation section, and the sample outlet section, and through which a cooling material is moved to cool the sample circulated in the sample circulation section along a movement path formed therein.

[0015] In addition, the ultrasonic vibration unit according to an embodiment of the present invention may include a first vibration member having a hollow semicircular cross section and spaced apart from a portion of the outer surface of the sample circulation unit, and a second vibration member having a hollow semicircular cross section opposite the first vibration member and spaced apart from another portion of the outer surface of the sample circulation unit, and forming a hollow circular cross section together with the first vibration member.

[0016] Furthermore, the first vibrating member and the second vibrating member according to the embodiment of the present invention may be made of piezoelectric ceramics.

[0017] Furthermore, the ultrasonic waves irradiated into the sample circulating section by the ultrasonic vibration section according to the embodiment of the present invention may have a frequency range of 350 to 700 kHz.

[0018] In addition, the sample circulating unit according to the embodiment of the present invention has inclined portions at both ends forming the circulation space, so that negative pressure disturbed during the circulation of the sample can be concentrated in the center.

[0019] Furthermore, the inclination angle of the inclined portion according to the embodiment of the present invention may be 10 to 80 degrees.

[0020] Meanwhile, a decomposition method of a persistent substance decomposition device according to an embodiment of the present invention may include a sample inflow step of inflowing a sample containing a persistent substance through a sample inflow portion, a sample circulation step of circulating the sample moved from the sample inflow portion in a circulation space through a sample circulation portion connected to be in communication with the sample inflow portion, and a decomposition step of applying ultrasonic waves to the sample in the sample circulation portion through an ultrasonic vibration portion surrounding at least a portion of the sample circulation portion to decompose the persistent substance contained in the sample.

[0021] In addition, the decomposition method according to an embodiment of the present invention may further include a discharge step, which is performed after the decomposition step, of discharging the sample containing the persistent substances decomposed by the ultrasonic vibration unit from the sample circulation unit through a sample discharge unit provided on one side of the sample circulation unit so as to face the sample inlet unit.

[0022] In addition, the decomposition method according to an embodiment of the present invention may further include a cooling step that is performed simultaneously with the sample circulation step and cools the sample that has passed through the sample circulation step using a cooling material that moves along a movement path formed inside a cooling section that passes through the center of the sample circulation section.

[0023] In addition, the frequency range of the ultrasonic waves transmitted to the sample in the sample circulator through the ultrasonic vibration unit during the decomposition step according to an embodiment of the present invention may be 350 to 700 kHz.

[0024] In addition, according to an embodiment of the present invention, the ultrasonic vibration unit that generates ultrasonic waves during the decomposition step may include a first vibration member having a hollow semicircular cross section and spaced apart from a portion of the outer surface of the sample circulation unit, and a second vibration member having a hollow semicircular cross section facing the first vibration member and spaced apart from another portion of the outer surface of the sample circulation unit, and forming a hollow circular cross section together with the first vibration member, and the first vibration member and the second vibration member may be made of piezoelectric ceramics.

[0025] Meanwhile, a cleaning method of a cleaning apparatus according to an embodiment of the present invention may include an inflow step of introducing an object to be cleaned through an inflow portion; a circulation step of circulating the object to be cleaned transferred from the inflow portion within a circulation space within the circulation portion through a circulation portion connected to the inflow portion; a cleaning step of transferring ultrasonic waves to the object to be cleaned in the circulation portion through an ultrasonic vibration portion surrounding at least a portion of the circulation portion to clean the object to be cleaned; and an outflow step of discharging the object to be cleaned that has been cleaned by the ultrasonic vibration portion from the circulation portion through an outflow portion provided on one side of the circulation portion opposite the inflow portion.

[0026] Furthermore, the object to be cleaned according to the embodiment of the present invention may be a substrate including a semiconductor wafer. [Effects of the Invention]

[0027] According to an embodiment of the present invention, ultrasonic waves can be directly applied to a sample containing a persistent substance such as a perfluorinated compound, thereby directly decomposing the persistent substance in the sample circulation section with high decomposition performance, and since the device structure is not complicated, it can be easily mass-produced. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a perspective view of an apparatus for decomposing persistent substances using ultrasound according to an embodiment of the present invention; [Figure 2] FIG. 2 is a schematic perspective view showing the internal structure of the decomposition device of FIG. 1 as projected. [Figure 3] FIG. 3 is a cross-sectional view showing the internal configuration of the decomposition device shown in FIG. 2. [Figure 4] FIG. 2 is a perspective view of the ultrasonic vibration unit shown in FIG. [Figure 5] 10 is a graph showing decomposition performance results according to the frequency range of ultrasonic waves generated from an ultrasonic vibration unit in an apparatus for decomposing persistent substances according to an embodiment of the present invention. [Figure 6] 2 is a flowchart of a decomposition method of a device for decomposing difficult-to-decompose substances according to an embodiment of the present invention. MODE FOR CARRYING OUT THE INVENTION

[0029] The advantages and / or features of the present invention and the methods for achieving them will become clearer with reference to the embodiments described below in detail in conjunction with the accompanying drawings.

[0030] However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various different forms. However, the present embodiments are provided so that the disclosure of the present invention will be complete and will fully convey the scope of the invention to those skilled in the art to which the present invention pertains. The present invention is defined only by the scope of the claims. Like reference characters refer to like elements throughout the specification.

[0031] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0032] FIG. 1 is a perspective view of an apparatus for decomposing persistent substances using ultrasound according to one embodiment of the present invention, FIG. 2 is a schematic perspective view showing the internal structure of the decomposition apparatus of FIG. 1 as projected, FIG. 3 is a cross-sectional view showing the internal configuration of the decomposition apparatus shown in FIG. 2, and FIG. 4 is a perspective view of the ultrasonic vibration unit shown in FIG. 1.

[0033] 1 to 3, an apparatus 100 for decomposing persistent substances using ultrasound according to one embodiment of the present invention is an apparatus for decomposing persistent substances such as perfluorinated compounds using ultrasound, and may include a sample inlet section 120, a sample circulation section 110, an ultrasonic vibration section 130, a sample outlet section 160, and a cooling section 140.

[0034] First, the sample inlet 120 of this embodiment may be formed in a hollow cylindrical shape, as shown in Fig. 1, into which a sample containing persistent substances is introduced. Although not shown, an inlet through which the sample is introduced is provided on one side of the sample inlet 120, and the sample introduced through the inlet can be transferred to the subsequent sample circulating unit 110 through a transfer path formed in the sample inlet 120.

[0035] As shown in Figures 1 and 2, the sample circulation section 110 of this embodiment may be connected to the sample inlet section 120 so as to be in communication with the sample, and may include a circulation space 110S in which the sample moved through the sample inlet section 120 is circulated.

[0036] 2 and 3, the sample circulation unit 110 may be provided in the shape of a hollow cylinder, and one end of the sample inlet unit 120 may be provided on one side of the sample circulation unit 110, so that the sample inlet unit 120 and the sample circulation unit 110 have a communication structure. The sample inlet unit 120, the sample circulation unit 110, and the sample outlet unit 160 may be formed integrally.

[0037] That is, the sample introduced through the inlet of the sample inlet unit 120 is transferred to the sample circulating unit 110 and circulated in the circulation space 110S of the sample circulating unit 110, where it undergoes a decomposition process.

[0038] 3, both ends forming the circulation space 110S of the sample circulation unit 110 may be provided with inclined portions 115. That is, based on FIG. 3, if the circulation space 110S of the sample circulation unit 110 is generally hollow and cylindrical, the inner diameter of both ends may be gradually reduced, and thus the sample circulation unit 110 may be provided with inclined portions 115.

[0039] The negative pressure disturbed when the sample circulates in the sample circulating section 110 can be concentrated in the center through the inclined portion 115, thereby increasing the decomposition efficiency.

[0040] Here, the inclination angle α of the inclined portion 115 may be 10 to 80 degrees based on the inner surface that forms the circulation space 110S of the sample circulation section 110. However, the inclination angle α of the inclined portion 115 is not limited to this.

[0041] Meanwhile, as shown in Figures 1 to 4, the ultrasonic vibration unit 130 of this embodiment is provided to surround the sample circulation unit 110 while being spaced apart from the central portion of the sample circulation unit 110, and generates ultrasonic waves in the direction of the circulation space 110S of the sample circulation unit 110, thereby providing ultrasonic waves to the sample circulating within the sample circulation unit 110, thereby decomposing persistent substances contained in the sample.

[0042] As shown in Figures 2 and 4, such ultrasonic vibration unit 130 may include a first vibration member 131 having a hollow semicircular cross section and spaced apart from a portion of the outer surface of the sample circulation unit 110, and a second vibration member 135 having a hollow semicircular cross section opposite the first vibration member 131 and spaced apart from another portion of the outer surface of the sample circulation unit 110, forming a hollow circular cross section together with the first vibration member 131.

[0043] That is, the first vibrating member 131 and the second vibrating member 135 have an overall circular ring shape, but their respective ends are spaced apart, and they are made of piezoelectric ceramics, so that they can generate ultrasonic waves and provide them into the sample circulation section 110.

[0044] The first and second vibrating members 131 and 135 are spaced apart from each other on the outer surface of the sample circulating unit 110, thereby protecting the internal electrode 150 provided in the sample circulating unit 110, and at the same time, since they are spaced apart from the internal electrode 150 by a predetermined distance, they can generate uniform energy.

[0045] However, in this embodiment, the ultrasonic vibration unit 130 is described as including a semicircular first vibration member 131 and a second vibration member 135, but it is not limited to this, and it is natural that three or more vibration members may have ring shapes spaced apart from each other.

[0046] The frequency range of the ultrasonic waves irradiated into the circulation space 110S of the sample circulation section 110 by the ultrasonic vibration section 130 may be, for example, 350 to 700 kHz.

[0047] This will be explained with reference to FIG.

[0048] FIG. 5 is a graph showing the decomposition performance results according to the frequency range of ultrasonic waves generated from the ultrasonic vibration unit in the device for decomposing persistent substances according to an embodiment of the present invention.

[0049] As shown in the figure, when the ultrasonic waves generated from the ultrasonic vibration unit 130 are, for example, 340 kHz, the decomposition performance of methylene blue is about 7.1%, when it is 700 kHz, the decomposition performance of methylene blue is about 38%, and when it is 400 kHz, the decomposition performance of methylene blue is 85.6%.

[0050] That is, it can be seen that when the frequency of the ultrasonic waves generated from the ultrasonic vibration unit 130 is 350 to 700 kHz, excellent decomposition performance can be achieved. In particular, it can be seen that the best decomposition performance can be achieved at 400 kHz.

[0051] Meanwhile, referring to Figures 1 and 2, the sample outlet 160 of this embodiment is provided on one side of the sample circulation unit 110 so as to face the sample inlet 120, and can discharge a sample containing persistent substances decomposed by the ultrasonic vibration unit 130 from the sample circulation unit 110.

[0052] The sample outlet 160 may have a hollow cylindrical shape corresponding to the sample inlet 120, and although not shown, an outlet is provided on one side to allow the decomposed sample to be discharged to the outside.

[0053] Meanwhile, as shown in FIGS. 1 and 2, the persistent substance decomposition device 100 of this embodiment may further include a cooling unit 140 for cooling in order to enhance decomposition performance.

[0054] As shown schematically in Figures 1 and 2, the cooling section 140 of this embodiment is configured to penetrate the center of the sample inlet section 120, the sample circulation section 110, and the sample outlet section 160, and a cooling material for cooling the sample circulating in the sample circulation section 110 can be transported along a transport path formed inside.

[0055] As a result, the sample circulating in the circulation space 110S of the sample circulation unit 110 exchanges heat with the cooling material of the cooling unit 140, thereby lowering the temperature of the sample.As a result, ultrasonic waves are provided from the ultrasonic vibration unit 130 to the cooled sample, thereby enabling better decomposition of persistent substances in the sample.

[0056] Meanwhile, the decomposition method of the persistent substance decomposition device 100 having the above-mentioned configuration will be described below with reference to the drawings.

[0057] FIG. 6 is a flowchart of a decomposition method for a persistent substance decomposition device according to one embodiment of the present invention.

[0058] As shown in the figure, the decomposition method of the persistent substance decomposition device 100 of this embodiment may include a sample inflow step S100, a sample circulation step S200, a decomposition step S400, and an outflow step S500. In addition, the sample circulation step S200 may further include a cooling step S300 that can be performed simultaneously.

[0059] Each step will be described below. First, in the sample inflow step S100 of this embodiment, a sample containing persistent substances can be inflowed through the sample inflow unit 120.

[0060] In the sample circulation step S200 of this embodiment, the sample transferred from the sample inlet 120 can be circulated within the circulation space 110S through the sample circulation unit 110 connected to be in communication with the sample inlet 120.

[0061] In this case, a cooling step S300 may be performed at the same time, and in the cooling step S300, the sample undergoing the sample circulation step S200 can be cooled using a cooling material that moves along a movement path formed inside the cooling section 140 that passes through the center of the sample circulation section 110.

[0062] In the decomposition step S400 of this embodiment, ultrasonic waves of 350 to 700 kHz are applied to the sample in the sample circulation unit 110 through the ultrasonic vibration unit 130 surrounding the sample circulation unit 110, thereby decomposing persistent substances contained in the sample.

[0063] Next, in the outflow step S500 of this embodiment, the sample containing the persistent substances decomposed by the ultrasonic vibration unit 130 from the sample circulation unit 110 can be outflowed through the sample outflow unit 160 to the outside.

[0064] As described above, according to one embodiment of the present invention, ultrasonic waves can be directly applied to a sample containing a persistent substance, such as a perfluorinated compound, to directly decompose the persistent substance with high decomposition performance in the sample circulating unit 110. Furthermore, since the structure of the device is not complicated, it can be easily mass-produced.

[0065] Meanwhile, a method for cleaning a cleaning device using ultrasonic waves according to another embodiment of the present invention will be described below, but a description of the content that is substantially the same as the method for disassembling a disassembly device according to the above-described embodiment will be omitted.

[0066] A cleaning method of a cleaning device according to another embodiment of the present invention may include an inflow step of introducing an object to be cleaned through an inflow portion, a circulation step of circulating the object to be cleaned transferred from the inflow portion within a circulation space within the circulation portion through a circulation portion connected to the inflow portion, a cleaning step of transferring ultrasonic waves to the object to be cleaned in the circulation portion through an ultrasonic vibration portion surrounding at least a portion of the circulation portion to clean the object to be cleaned, and an outflow step of discharging the object to be cleaned that has been cleaned by the ultrasonic vibration portion from the circulation portion through an outflow portion provided on one side of the circulation portion opposite the inflow portion.

[0067] Here, the object to be cleaned may be a substrate including a semiconductor wafer.

[0068] In this manner, in this embodiment, ultrasonic waves can be used to directly clean semiconductor wafers and the like efficiently and accurately.

[0069] Although specific embodiments of the present invention have been described above, it is obvious that various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the appended claims and equivalents thereof.

[0070] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited to the above-described embodiments, and various modifications and variations can be made by those skilled in the art based on such descriptions. Therefore, the concept of the present invention should be understood only by the appended claims, and all equivalent or similar modifications should be considered to fall within the scope of the concept of the present invention.

Claims

1. a sample inlet portion into which a sample containing persistent substances is introduced; a sample circulation unit connected to the sample inlet unit so as to communicate with the sample inlet unit, the sample circulation unit including a circulation space through which the sample transferred via the sample inlet unit is circulated; and an ultrasonic vibration unit that surrounds at least a portion of the sample circulation unit so as to be spaced apart from the outer surface of the sample circulation unit, and generates ultrasonic waves to apply them to the sample circulating within the sample circulation unit, thereby decomposing the persistent substances in the sample; An apparatus for decomposing persistent substances using ultrasound, comprising:

2. 2. The device for decomposing persistent substances using ultrasound according to claim 1, further comprising a sample outlet portion provided on one side of the sample circulation portion so as to face the sample inlet portion and configured to discharge the sample containing the persistent substances decomposed by the ultrasonic vibration portion from the sample circulation portion.

3. 3. The apparatus for decomposing persistent substances using ultrasound according to claim 2, further comprising a cooling unit that is provided to pass through the centers of the sample inlet, the sample circulation unit, and the sample outlet, and through which a cooling material is moved to cool the sample circulated in the sample circulation unit along a moving path formed therein.

4. The ultrasonic vibration unit is a first vibration member having a hollow semicircular cross section and provided so as to be spaced apart from a portion of the outer surface of the sample circulation portion; and a second vibration member having a hollow semicircular cross section facing the first vibration member, and spaced apart from another part of the outer surface of the sample circulating portion, and forming a hollow circular cross section together with the first vibration member; The device for decomposing persistent substances using ultrasound according to claim 1, comprising:

5. 5. The device for decomposing persistent substances using ultrasound as set forth in claim 4, wherein the first vibrating member and the second vibrating member are made of piezoelectric ceramics.

6. 5. The device for decomposing persistent substances using ultrasound according to claim 4, wherein the frequency range of the ultrasound irradiated into the sample circulating section by the ultrasonic vibration section is 350 to 700 kHz.

7. 2. The device for decomposing persistent substances using ultrasound as described in claim 1, characterized in that both ends of the sample circulation section that form the circulation space are provided with inclined portions that extend diagonally, thereby concentrating negative pressure that is disturbed when the sample is circulated in the center.

8. 8. The device for decomposing persistent substances using ultrasound according to claim 7, wherein the inclined portion has an inclination angle of 10 to 80 degrees.

9. a sample inlet step of injecting a sample containing persistent substances through a sample inlet; a sample circulating step of circulating the sample transferred from the sample inlet through a sample circulating part connected to be in communication with the sample inlet in a circulation space; and a decomposition step of applying ultrasonic waves to the sample in the sample circulation unit through an ultrasonic vibration unit surrounding at least a portion of the sample circulation unit to decompose the persistent substances contained in the sample; A decomposition method for a device for decomposing difficult-to-decompose substances using ultrasound, comprising:

10. 10. The decomposition method of claim 9, further comprising a discharge step, which is performed after the decomposition step, of discharging the sample containing the persistent substances decomposed by the ultrasonic vibration unit from the sample circulation unit through a sample discharge unit provided on one side of the sample circulation unit so as to face the sample inlet unit.

11. 10. The decomposition method of a device for decomposing persistent substances using ultrasound according to claim 9, further comprising a cooling step, which is performed simultaneously with the sample circulation step and cools the sample that has passed through the sample circulation step using a cooling material that moves along a moving path formed inside a cooling unit that passes through the center of the sample circulation unit.

12. 10. The method of claim 9, wherein the frequency of the ultrasonic waves transmitted to the sample in the sample circulating unit through the ultrasonic vibration unit during the decomposition step is in the range of 350 to 700 kHz.

13. The ultrasonic vibration unit that generates ultrasonic waves during the decomposition step a first vibration member having a hollow semicircular cross section and provided so as to be spaced apart from a portion of the outer surface of the sample circulation portion; and a second vibration member having a hollow semicircular cross section facing the first vibration member, and spaced apart from another part of the outer surface of the sample circulating unit, and forming a hollow circular cross section together with the first vibration member; 13. The method of claim 12, wherein the first and second vibration members are made of piezoelectric ceramics.

14. an inlet step of inflowing the object to be cleaned through an inlet; a circulating step of circulating the object to be cleaned transferred from the inlet through a circulation unit connected to the inlet within a circulation space within the circulation unit; a cleaning step of cleaning the object by transmitting ultrasonic waves to the object in the circulation unit through an ultrasonic vibration unit surrounding at least a part of the circulation unit; and a discharging step of discharging the object cleaned by the ultrasonic vibration unit in the circulation unit through an outlet provided on one side of the circulation unit so as to face the inlet; 1. A method for cleaning a cleaning device using ultrasonic waves, comprising:

15. 15. The method for cleaning a cleaning device using ultrasonic waves according to claim 14, wherein the object to be cleaned is a substrate including a semiconductor wafer.

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