Air purifier

Abstract

The present invention comprises a housing (2) having an air intake (3) into which contaminated air is introduced and an air outlet (4) through which purified air is discharged; a blower fan (5) that draws in the flow of purified contaminated air passing through the housing (2); a recirculation pipe (7) that generates a contaminated solvent by recirculating a solvent within the housing (2) and bringing the solvent into contact with the contaminated air; a contact unit (8) configured to bring the recirculated solvent into contact with the contaminated air during the recirculation process; and a tank located at the bottom of the housing (2) for recovering the contaminated solvent. An air purifier (1) comprising (9) and a solvent monitoring unit (10) adapted to monitor the quality of the contaminated solvent recovered therein, wherein the solvent monitoring unit (10) comprises a pH sensor (11) for measuring the pH of the recovered contaminated solvent, a solvent resistivity sensor (12) for measuring the electrical resistance of the recovered contaminated solvent, and an illumination indicator (13) coupled to the pH sensor (11) and the solvent resistivity sensor (12) for indicating the pH and ionic substance content of the recovered contaminated solvent, as well as the time to replace the tank (9).

Description

[Technical Field]

[0001] The present invention relates to an air cleaning device capable of effectively removing contaminants from air. More generally, the present invention relates to air cleaners, and more specifically, to electric air cleaners for household use. [Background Art]

[0002] In general, an air cleaner removes and eliminates contaminants by passing contaminated air containing fine dust particles, harmful gases, and microorganisms such as bacteria, mold and viruses through a purification medium or cleaning medium, and then discharges substantially purified or cleaned air. Air cleaners have not only an air purification function, but also other useful functions such as a function of removing fine particles including odorous chemical molecules, mites, pollen, pet hair and the like. In some cases, air cleaners may have a function of preventing airborne infections. The basic configuration of an air cleaner may include an inlet for drawing in contaminated air, means for filtering and removing contaminants from the air, and an outlet for discharging cleaned or purified air.

[0003] Air purifiers can be broadly classified into two types: conventional direct capture air purifiers that use filters, and solvent absorption air purifiers. Direct capture air purifiers use filters with smaller pore sizes to capture larger particles to prevent them from passing through, while solvent absorption air purifiers use both suction and absorption processes to capture both particles and gases into a solvent. Filter-type air purifiers exhibit high purification performance because various types of particulate matter are removed as the air passes through the filter. Therefore, filter-type air purifiers are suitable for filtering out fine dust particles from the air. However, this type of air purifier has a clear and common drawback: it removes only airborne particles and cannot remove harmful gases. In addition, filter-type air purifiers are known to re-disperse particles under certain conditions (when the filter is full of particles) or when disturbed. Furthermore, if airflow is restricted due to the pore size of the filter, the purification process deteriorates over time. Considering that current Air Quality Index (AQI) measurements take into account not only PM2.5 but also harmful gases such as sulfur oxides (SOx), nitrogen oxides (NOx), and ozone in the air, direct capture air purifiers that use filters cannot purify these harmful gases.

[0004] Solvent absorption air purifiers are particularly advantageous in that they operate by purifying air by bringing the drawn-in air into contact with a solvent, usually water but not limited to water, thereby absorbing airborne pollutants such as particles and harmful gases into the solvent. Ideally, the pollutants in the drawn-in air are absorbed by the solvent and collected in a storage tank, which can be disposed of periodically. As a result, the purified or cleaned air is discharged from the air purifier without the need for filter replacement. The solvent is recirculated within the air purifier for the purpose of absorbing particles and harmful gases. Furthermore, depending on the choice of solvent used, toxic gases such as hydrogen cyanide can also be removed from the polluted air. For these reasons, solvent absorption air purifiers are generally more advantageous than direct capture air purifiers.

[0005] Several technologies related to wet air purifiers have been established. For example, Chinese Patent Publication No. CN104056511A discloses a water-filtration humidifying air purifier consisting of a shell, a liner, and a water tank. An air outlet is provided at the top of the shell, the bottom of the shell is connected to the bottom of the liner, a centrifugal fan is located at the top of the liner, a water dispenser is located below the centrifugal fan, a packing layer is located below the water dispenser, and an air intake is located below the packing layer. A water tank is located at the bottom, and a water pump is provided inside it, with the discharge pipe of the water pump connected to the water dispenser. Basically, water is pumped from the water tank to the water dispenser via piping, then sprayed from the water dispenser onto the packing layer, passes through it and returns to the water tank, completing the water recirculation. Air is drawn in by a centrifugal blower, so that substantially contaminated air comes into contact with the recirculating water, during which time purified air is discharged through the centrifugal blower. The problem with this invention is that the conical shape of the shell increases the air velocity, which in turn increases the risk of more droplets being ejected and re-contaminating the air. The purpose of this invention is not to capture airborne particles, impurities, and gases, but to humidify the air. Furthermore, a major drawback of this device is that it does not have an indicator to show when the solvent should be replenished or when it is empty. Another similar technology is disclosed in Chinese Patent Publication No. CN106310846A, which describes a water-washing air purifier in which a fan is positioned at the top of a purification tower equipped with a gas outlet, and one side of the purification tower equipped with a water intake is located above a packing layer. The packing layer is positioned below the purification tower, and a water tank is positioned at the bottom of the purification tower, with an air intake and a water pump located inside the water tank. The discharge port of the water pump is connected to the water intake so that water is injected into the water tank, and a housing is provided that covers the fan, purification tower, and packing layer. Another related technology is exemplified in U.S. Patent Publication No. US20180147523A1, which discloses a wet air purifier that removes pollutants by bringing polluted air into contact with water as the polluted air passes through it.In particular, this wet air purifier draws in outside air by rotating an internal fan, and disperses water droplets by causing them to collide with the fan, thereby increasing the contact area between the air and water. The mixture of contaminated outside air and water is then guided through a long, narrow passage to a storage tank where the contaminants settle.

[0006] The main difference between CN106310846A and US20180147523A1 is that these devices are intended for industrial use rather than household use. Furthermore, the above technology is unsuitable for household use because it creates a gap between the packing material and the liquid level in the tank, resulting in noise from water splashing. [Overview of the project] [Problems that the invention aims to solve]

[0007] One aspect of the present invention is to provide an air purifier that can continuously remove pollutants from contaminated air drawn into the air purifier from the surrounding environment. In particular, this air purifier controls the peripheral velocity of the air in contact with the liquid in the random filling to maximize mass transfer between the air and the liquid.

[0008] Another aspect of the present invention is to provide an air purifier that is based on an absorption process by chemical mass transfer between polluted air and a solvent, thereby generating a polluted solvent containing pollutants, which can then be disposed of. The advantage is that the air is effectively purified by the absorption process and discharged from the air purifier into the surrounding environment.

[0009] Furthermore, one aspect of the present invention is to provide an air purifier having a solvent quality monitoring function and a notification function that informs the user to discard contaminated solvent and replenish with new solvent. The level transmitter in the tank also indicates the solvent level if it is low. [Means for solving the problem]

[0010] At least one of the aforementioned objectives is achieved, in whole or in part, by the following embodiment, which discloses an air purifier comprising: a housing having an air intake into which contaminated air is introduced and an air outlet from which purified air is discharged; a blower fan for drawing a flow of purified contaminated air into the housing; a recirculation pipe for generating a contaminated solvent by recirculating a solvent within the housing and bringing the solvent into contact with contaminated air; a contact unit configured to bring the recirculated solvent into contact with contaminated air during recirculation; a tank located at the bottom of the housing for recovering the contaminated solvent; and a solvent monitoring unit adapted to monitor the quality of the contaminated solvent recovered therein, wherein the solvent monitoring unit comprises a pH sensor for measuring the pH of the recovered contaminated solvent.

[0011] In a preferred embodiment of the present invention, the recirculation pipe is connected to the lower part of the housing at one end to fluid communication with the tank, and the other end is connected to the upper part of the housing.

[0012] In another preferred embodiment of the present invention, the recirculation pipe extends into the upper part of the housing to recirculate the contaminated solvent from the tank to the contact unit.

[0013] In a further embodiment of the present invention, it is disclosed that the recirculation pipe is provided with a pump for pumping the contaminated solvent.

[0014] Preferably, the contact unit is positioned between the other end of the recirculation pipe and the air intake at the top of the housing.

[0015] More preferably, the contact unit is a packed bed having multiple passages through which the contaminating solvent flows downward and the purified air that has passed through the packed bed passes upward.

[0016] More preferably, the packed layer is formed from a copper metal material.

[0017] More preferably, the packed bed has a packing configuration selected from structured packing and random packing.

[0018] More preferably, the contact unit comprises a tray for guiding contaminated solvent into the tank, and the tray is provided on a lower surface of the contact unit.

[0019] It is preferable that the pH sensor and the solvent resistivity sensor are installed in a space inside the tank.

[0020] Preferably, the blower fan is disposed in contact with an upper portion of the housing.

[0021] More preferably, the blower fan is connected to a motor for operation thereof.

[0022] Those skilled in the art will readily appreciate that the present invention is well adapted to carry out the above-described objects and advantages, and also to attain the objects and advantages inherent therein. The embodiments described herein are not intended to limit the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] To facilitate understanding of the present invention, preferred embodiments are shown in the accompanying drawings. When considered together with the following description, the present invention, its structure and operation, and its numerous advantages will be readily understood.

[0024] [Figure 1] 1 is a perspective view showing an air cleaning apparatus according to the present invention. MODE FOR CARRYING OUT THE INVENTION

[0025] Hereinafter, the present invention will be described according to preferred embodiments of the present invention with reference to the accompanying description and drawings. However, the limitation to preferred embodiments in the description of the present invention is merely for facilitating the description of the present invention, and it should be understood that those skilled in the art can conceive various modifications without departing from the scope of the appended claims.

[0026] Hereinafter, the present invention will be described in further detail with reference to the drawings.

[0027] Referring particularly to Fig. 1, there is shown an embodiment of an air cleaning apparatus 1 constructed in accordance with the present invention. In a preferred embodiment, the air cleaning apparatus 1 mainly comprises a housing 2 forming the outer appearance of the apparatus. The housing 2 has a space therein for a purified air flow and discharge of contaminated solvent. The housing 2 can be variously and conveniently configured depending on the size of the air cleaning apparatus 1. For example, the housing 2 may have a substantially rectangular parallelepiped shape. Alternatively, if desired, the housing 2 may have a substantially cylindrical shape.

[0028] The housing 2 may be provided with an air intake 3 through which contaminated air is introduced into the housing, and an air outlet 4 through which substantially purified air is discharged from the housing 2 to the outside. Referring to Fig. 1, the air intake 3 may be formed as a through slit formed in a side wall 19 of the housing 2, whereby an opening is defined for allowing contaminated air drawn from the outside environment to pass into the housing 2 of the air cleaning apparatus 1. Preferably, the housing 2 may be provided with a plurality of air intakes 3 arranged at regular intervals along the side wall on each side thereof, whereby the amount of contaminated air introduced can be substantially increased to substantially enhance the air cleaning capacity of the air cleaning apparatus 1. Optionally, the air intakes 3 may be formed as through holes as required. According to a preferred embodiment of the present invention, the air outlet 4 is arranged at an upper portion of the housing 2. In short, substantially purified air is discharged from the housing 2 through the air outlet 4. For this reason, the upper portion of the housing 2 may be open.

[0029] As shown in Figure 1, the blower fan 5 may be fixedly installed at the lower upper part of the housing 2 so as to communicate with it, in which case the blower fan 5 is arranged horizontally. That is, multiple blades 6 are arranged horizontally. In particular, the blower fan 5 operates on the principle that the rotation of the blades 6 introduces air from around the blower fan 5 into its interior, and then it is discharged through the top of the blower fan 5. According to a preferred embodiment of the present invention, the blower fan 5 may be connected to a motor 18 for its operation, and the motor 18 is connected to the lower part of the blower fan 5. When the motor 18 is operating, the blower fan 5 rotates in one direction, and as a result, contaminated air from outside is forcibly introduced into the housing 2 through the air intake 3.

[0030] Before substantially purified air is discharged through the air outlet 4, the air purifier 1 mixes the contaminated air introduced into the housing 2 via the air intake 3 with a solvent, where particulate matter and harmful gases in the contaminated air are absorbed into the solvent, and as a result, purified air is discharged from the housing 2. As shown in Figure 1, the air purifier 1 includes a recirculation pipe 7 for generating a contaminated solvent by recirculating the solvent within the housing 2 and bringing the solvent into contact with the contaminated air. The contaminated solvent flows through a solvent guide, particularly to reduce the splashing and dripping noises of the solvent. A tank 9 is located at the bottom of the housing 2 to collect the contaminated solvent.

[0031] In a preferred embodiment of the present invention, the recirculation pipe 7 is connected to the lower part of the housing 2 at one end 14 to fluidly communicate with the tank 9, and the other end 15 is connected to the upper part of the housing 2. The recirculation pipe 7 further extends upward from the lower part to the upper part of the housing 2. When in operation, the solvent from the tank 9 is recirculated upward through the recirculation pipe 7, and as a result, the recirculated solvent reaches the upper part of the housing 2. Preferably, the recirculation pipe 7 is provided with a pump 16 to facilitate the pumping of the solvent from the tank 9. The other end 15 of the recirculation pipe 7 is also preferably configured to extend into the upper part of the housing 2 in order to recirculate the contaminated solvent within the housing 2.

[0032] To increase mass transfer between the recirculated solvent and the contaminated air within the housing 2 of the air purifier 1, a contact unit 8 may be detachably installed inside the housing 2. According to a preferred embodiment of the present invention, the contact unit 8 is configured to bring the recirculated solvent into contact with the contaminated air during the recirculation process. For this reason, the contact unit 8 is preferably a packed bed and has multiple passages through which the contaminated solvent supplied from the other end 14 of the recirculation pipe 7 flows downward, and through which the purified air filtered by passing through the packed bed passes upward. The packed bed of the contact unit 8 can be made of a variety of materials, including but not limited to perforated embossed metal or plastic or corrugated wire mesh sheets. Preferably, the packed bed is made of a copper metal material. The advantage of the copper metal material is that it imparts natural antibacterial and antiviral properties to the contact unit 8, thereby substantially improving the efficiency of the air purifier 1. The operating principle is that, by mixing the recirculated solvent and the contaminated air in the contact unit 8, the contaminated solvent, which may contain bacteria and microbial particles, can undergo antibacterial purification.

[0033] In short, the packed bed configuration of the contact unit 8 is not limited to those described above, and as a result, it may be any configuration as long as it provides a substantially inclined passage for the contaminated solvent to flow downward and the purified air to pass upward through its interior. For example, the packed bed of the contact unit 8 has a high surface area and low gas resistance, which ideally maximizes the mass transfer of the recirculating solvent by providing an additional interface area for contact between the contaminated air and the recirculating solvent, and also assists the upward flow of the purified air discharged from the housing 2 of the air purifier 1. Therefore, it is preferable that the packed bed of the contact unit 8 has a packing configuration selected from structured packing and random packing. Generally, a packed bed with a structured packing configuration uses a fixed and organized packing structure to guide the liquid or fluid into a specific shape and provides a large surface area for contact with the liquid or fluid without creating resistance that would impede its flow. On the other hand, a packed bed with a random packing configuration uses a random distribution of small packing materials to assist the separation process. The small material fragments in these random packings are designed to form a large surface area where liquids and fluids can interact, while maximizing the surface area-to-volume ratio and minimizing pressure loss. While not intended to be constrained by theory, the packing bed may be selected from any of the above configurations depending on the convenience and application of the air purifier 1.

[0034] As shown in Figure 1, the contact unit 8 is preferably positioned between the other end 15 of the recirculation pipe 7 and the air intake 3 at the top of the housing 2. Ideally, the other end 15 of the recirculation pipe 7 may be provided with a solvent dispersion unit (not shown) to facilitate uniform dispersion of the solvent onto the contact unit 8. For example, the solvent dispersion unit may be a spray nozzle for spraying the solvent onto the contact unit 8. This arrangement allows the solvent, which has been recirculated from the tank 9 through the recirculation pipe 7 to the other end 15, to be supplied to the contact unit 8 for air purification. When a contaminated solvent is subsequently generated by the exchange of contaminated air with the recirculated solvent, the contaminated solvent flows downward through the inclined passage of the structured packing of the contact unit 8 by gravity and solvent pressure. To prevent the contaminated solvent from being unnecessarily scattered when it is collected in the tank 9, a solvent guide 17 may be provided on the underside of the contact unit 8 to guide the contaminated solvent into the tank 9. The tray 17 may have a plurality of tubular elements 20 that form a flow path for guiding the contaminated solvent into the tank 9. Therefore, the tubular element 20 may be configured to extend downward so as to be substantially immersed in the contaminated solvent recovered in the tank 9.

[0035] As described above, the basic arrangement of the air purifier 1 allows for continuous recirculation of the solvent and intake of contaminated air within the housing 2, thereby enabling continuous operation of air purification. However, in such conventional air purification mechanisms, saturation and sedimentation of the contaminated solvent collected in the tank 9 occur. Furthermore, if the user of the air purifier 1 is unaware of the saturation and sedimentation of the contaminated solvent, continuous recirculation to supply the contaminated solvent to the contact unit 8 may cause blockage of the recirculation pipe 7 and the contact unit 8 due to the eventual saturation of the contaminated solvent and the accumulation of particulate pollutants. As a result, this may reduce the air purification performance of the air purifier 1.

[0036] The present invention provides a unique configuration that eliminates such inconveniences. In particular, the air purifier 1 includes a solvent monitoring unit 10 adapted to monitor the quality of the contaminated solvent collected in the tank 9, as illustrated in Figure 1. A preferred embodiment of the present invention further includes a pH sensor 11 for measuring the pH of the collected contaminated solvent, a solvent resistivity sensor 12 for measuring the electrical resistance of the collected contaminated solvent, and an illumination indicator 13 coupled to the pH sensor 11 and the solvent resistivity sensor 12. The pH sensor 11 may be any type of pH sensing device capable of precisely measuring the pH value of the collected contaminated solvent in the tank 9. The solvent resistivity sensor 12 may also be any type of solvent resistivity measuring device capable of precisely measuring the electrical resistance of the collected contaminated solvent. In particular, the solvent resistivity sensor 12 is configured to monitor the ionic purity of the collected contaminated solvent. Preferably, the pH sensor 11 and the solvent resistivity sensor 12 are installed in the space within the tank 9 so that they are in direct contact with the collected contaminated solvent being measured.

[0037] In particular, the illumination indicator 13 serves to display the pH of the recovered contaminated solvent, the solvent resistivity, and the timing for replacing the solvent in the tank. For this reason, the illumination indicator 13 may include a first illumination 21 that indicates the pH value of the recovered contaminated solvent. The illumination indicator 12 may also include a second illumination 22 that indicates the measured solvent resistivity of the recovered contaminated solvent. It is also preferable to include a third illumination 23 that indicates the timing for replacing the solvent in the tank 9. According to a preferred embodiment of the present invention, the illumination indicator 12 is installed on the lower outside of the housing 2.

[0038] The first light 21 is provided to inform the user of the quality of the contaminated solvent recovered in the tank 9 in terms of its pH value. For example, the first light 21 may emit light of a different color depending on the pH value of the recovered contaminated solvent. For example, when the pH of the recovered contaminated solvent is low, the first light 21 may emit red light. Alternatively, when the pH of the recovered contaminated solvent is high, the first light 21 may emit blue light. It is also preferable that the first light 21 emit green light when the solvent in the tank 9 is substantially neutral, that is, when the solvent has been newly replenished in the tank 9.

[0039] Similarly, the second illumination 22 is provided to inform the user of the quality of the contaminated solvent recovered in the tank 9 in terms of its ionic substance content. In particular, this refers to the ionic concentration content in the recovered contaminated solvent. An exemplary operating principle is that the solvent resistivity decreases as the ionic concentration in the recovered contaminated solvent increases. Therefore, the second illumination 22 enables notification to the user so that they can recognize the purity level of the recovered contaminated solvent. For example, the second illumination 22 may emit light of different colors depending on the measured solvent resistivity of the recovered contaminated solvent.

[0040] In short, appropriate colored light-emitting diodes can be used for the first illumination 21 and the second illumination 22, respectively. It should be understood that the configuration of the first illumination 21 and the second illumination 22 is not limited to the above and can be changed to suit any desired order and arrangement. In this way, the light emission state of the first illumination 21 and the second illumination 22 changes according to the quality of the contaminated solvent recovered in the tank 9, thereby allowing the user to check and evaluate the operating state and performance of the air purifier 1. Therefore, it is advantageous in that the user can also identify the degree of indoor air pollution or whether the operation of the air purifier 1 is inefficient or efficient through the evaluation of the first illumination 21 and the second illumination 22.

[0041] As shown in Figure 1, the third light 23 is provided to notify the user when it is necessary to discard the contaminated solvent recovered in the tank 9 and replenish it with new recirculating solvent. For this reason, the third light 23 may be configured to emit light of a different color or flash in a different pattern to warn the user when it is time to discard the contaminated solvent recovered in the tank 9 and when it is time to replenish it with new recirculating solvent. In the above description, the time to change the solvent, the time to discard the recovered contaminated solvent, or the time to replenish it with new recirculating solvent are indicated by the lighting means, but the notification function can be implemented by various methods such as visual displays.

[0042] When a solvent, including but not limited to water, undergoes mass transfer with air containing harmful gases such as nitrogen oxides (NOx) and sulfur oxides (SOx), the water becomes acidic, and its pH value changes. If ozone dissolves in water within the filled area, the pH meter will indicate an alkaline value. If toxic gases such as hydrogen cyanide dissolve in water, the pH meter will also indicate an alkaline value. When water, which is normally neutral with a pH of 7, becomes acidic or alkaline, it indicates that water replenishment is necessary. A solvent resistivity sensor is also provided to measure the electrical resistance of the recovered contaminated solvent. Pure water typically has a resistivity of 18.2 MΩ. Solvents, such as tap water, typically have a resistivity range of 1000 to 5000 Ω. When both acidic and alkaline gases are absorbed, their action reduces the resistivity of the solvent or water. A logic controller provides instructions to display the resistivity, pH value, and solvent level in the tank. Based on the pH or resistivity value, the logic controller instructs the necessary solvent or water replacement.

[0043] This disclosure includes the contents of the above description in addition to those described in the appended claims. Although the present invention has been described in some detail in its preferred embodiment, this disclosure relating to the preferred embodiment is illustrative only, and it should be understood that numerous modifications can be made to the details of the configuration, the combination and arrangement of components without departing from the scope of the invention.

Claims

1. A housing (2) having an air intake (3) into which contaminated air is introduced and an air outlet (4) into which purified air is discharged, A blower fan (5) draws in a flow of contaminated air that is purified by passing through the housing (2), A recirculation tube (7) generates a contaminated solvent by recirculating the solvent within the housing (2) and bringing the solvent into contact with the contaminated air, A contact unit (8) configured to bring the recycled solvent into contact with the contaminated air during the recirculation process, A tank (9) is located at the bottom of the housing (2) to recover the contaminated solvent, The system comprises a solvent monitoring unit (10) adapted to monitor the quality of the contaminated solvent recovered in the tank (9), The solvent monitoring unit (10) is an air purifier (1) comprising a pH sensor (11) for measuring the pH of the recovered contaminated solvent, a solvent resistivity sensor (12) for measuring the electrical resistance of the recovered contaminated solvent, and an illumination indicator (13) coupled to the pH sensor (11) and the solvent resistivity sensor (12) for displaying the pH of the recovered contaminated solvent, the ionic substance content, and the replacement time for the tank (9).

2. The apparatus according to claim 1, wherein the recirculation pipe (7) is connected to the lower part of the housing (2) at one end (14) so ​​as to be in fluid communication with the tank (9), and the other end (15) is connected to the upper part of the housing (2).

3. The apparatus according to claim 1 or 2, wherein the recirculation pipe (2) extends into the upper part of the housing (2) in order to recirculate the contaminated solvent from the tank (9) to the contact unit (8).

4. The apparatus according to any one of claims 1 to 3, wherein the recirculation pipe (7) is provided with a pump (16) for pumping the contaminated solvent.

5. The apparatus according to any one of claims 1 to 4, wherein the contact unit (8) is located between the other end (15) of the recirculation pipe (7) and the air intake (3) at the top of the housing (2).

6. The apparatus according to any one of claims 1 to 5, wherein the contact unit (8) is a packed bed having a plurality of passages, the plurality of passages through which the contaminating solvent flows downward and the air purified by passing through the packed bed passes upward.

7. The apparatus according to any one of claims 1 to 6, wherein the packed layer is formed from a copper metal material.

8. The apparatus according to any one of claims 1 to 7, wherein the packed bed has a packing configuration selected from structured packing and random packing.

9. The apparatus according to any one of claims 1 to 8, wherein the contact unit (8) is provided with a solvent guide (17) for guiding the contaminated solvent into the tank (9), and the solvent guide (17) is provided on the lower surface of the contact unit (8).

10. The apparatus according to any one of claims 1 to 9, wherein the pH sensor (11) and the solvent resistivity sensor (12) are installed in the space within the tank (9).

11. The apparatus according to any one of claims 1 to 10, wherein the illumination indicator (13) is installed on the lower outer side of the housing (2).

12. The apparatus according to any one of claims 1 to 11, wherein the blower fan (5) is installed in contact with the upper part of the housing (2).

13. The apparatus according to any one of claims 1 to 12, wherein the blower fan (5) is connected to a motor (18) for its operation.

Images