JP2007285663A - Sterilization mechanism for cooling tower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sterilization mechanism capable of effectively sterilizing cooling water passing through a cooling tower by using a sterilizing effect of a photocatalyst. <P>SOLUTION: The sterilization mechanism is for cooling water of an air-conditioning mechanism provided with an open type cooling tower 14. In addition to a circulation passage circulating and supplying the cooling water to a heat exchanger 22 of the air-conditioning mechanism via the cooling tower 10, a purification circulation passage is individually provided for partially taking in the cooling water from the cooling tower 10, and circulating and returning the cooling water to the cooling tower 10 via a photocatalyst device 36. A pump 30 circulating the cooling water in the purification circulation passage, and a separator 34 arranged in a precedent stage of the photocatalyst device 36 and separating solid matter mixed in the cooling water are provided in the purification circulation passage. It is characterized by that spherically formed photocatalyst materials are placed on support shelves arranged at predetermined intervals in the photocatalyst device 36, and ultraviolet lamps irradiating ultraviolet rays on the photocatalyst materials are arranged in the middle parts of the support shelves. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cooling tower sterilization mechanism, and more particularly to a cooling tower sterilization mechanism that sterilizes cooling water using a photocatalyst.

  The cooling tower is used as a device that cools water used as a cooling medium in an air-conditioning mechanism by using heat of vaporization of water. In the cooling tower, water circulating from the air conditioning mechanism is brought into contact with the air flow generated by the fan, cooled by vaporization heat, and returned to the air conditioning mechanism. Because the cooling tower is an open system that contacts the outside air with the water, when the cooling water passes through the cooling tower, it is easy to take in germs and dust from the outside, and the germs and dust taken into the cooling water return with the water. As a result, fungi such as Legionella grow in the cooling water and clog piping. Especially in the summer, there was a problem that the fungi were likely to grow as the outside air temperature increased, and the fungi were scattered outside, which adversely affected the environment.

As a method for solving such a problem of cooling water contamination by the cooling tower, a method of sterilizing by introducing a sterilizing agent from a replenishment pipe of the cooling tower (see, for example, Patent Documents 1 and 2), an ozone generator A method of sterilizing cooling water by using (for example, see Patent Documents 3 and 4), a method of fixing a photocatalyst to a cooling tower and using an oxidation action by the photocatalyst to suppress the generation of algae and slime (for example, see Patent Document 5) Has been proposed.
JP-A-9-184690 JP 2005-319381 A JP 2000-157985 A JP 2003-245673 A JP 2002-147994 A

  Although it is effective to use chemicals as a method for solving the problem of cooling water contamination in the cooling tower as described above, when chemicals are introduced into the cooling water, the chemicals are combined with the cooling water in the piping of the air conditioning mechanism. Since it will flow, there exists a possibility that a chemical | medical agent may leak, or piping may be damaged by a chemical | medical agent. In addition, the method using the ozone apparatus has a problem that piping or the like may be damaged when the ozone concentration is high, and the ozone concentration is likely to fluctuate depending on the temperature of the cooling water, and it is difficult to accurately exhibit the bactericidal action. there were.

On the other hand, the method using a photocatalyst sterilizes fungi due to the oxidizing action of the photocatalyst, so there is no fear that the chemical solution leaks or the air conditioning mechanism is damaged, but the sterilizing action by the photocatalyst works properly. Without effective control, there was a problem that an effective bactericidal action could not be obtained.
The present invention has been made to solve these problems, and in particular, when the cooling water passing through the cooling tower is sterilized by utilizing the sterilization action by the photocatalyst, the sterilization of the cooling tower capable of performing effective sterilization. The purpose is to provide a mechanism.

The present invention has the following configuration in order to achieve the above object.
That is, a cooling tower sterilizing mechanism used for sterilization and purification of cooling water of an air conditioning mechanism including an open type cooling tower, and circulatingly supplying the cooling water to the heat exchanger of the air conditioning mechanism via the cooling tower Separately from the circulation path, a purification circulation path that partially takes in the cooling water from the cooling tower and circulates the cooling water back to the cooling tower via the photocatalyst device is provided independently. A pump that circulates the cooling water in the circulation path and a separator that is disposed in front of the photocatalyst device and separates solid matter mixed in the cooling water are provided, and the photocatalyst device is disposed at a predetermined interval. A photocatalyst material formed in a spherical shape is arranged on a support shelf, and an ultraviolet lamp for irradiating the photocatalyst material with ultraviolet rays is arranged in the middle of the support shelf. To.
The purification circulation path may have a piping configuration that takes cooling water from the water tank of the cooling tower and returns the cooling water after passing through the photocatalyst device to the watering portion of the cooling tower.

  Further, when the photocatalyst material collides titanium fine particles with the surface of an alumina substrate made of alumina formed into a spherical shape at a speed close to the speed of sound, and the collision energy at the time of collision is converted into thermal energy, the titanium fine particles Is a titanium catalyst material deposited on the surface of an alumina substrate as titanium oxide and formed on a smooth surface, so that the photocatalytic action can be effectively applied to the cooling water, and on the surface of the photocatalyst material. Dirt is less likely to adhere and the photocatalytic action can be effectively exhibited.

  In addition, the separator is separated from the solid liquid by centrifugal force when the cooling water fed from the upper part of the main body formed in the separation cylinder rotates and moves along the inner wall surface of the separation cylinder. The solid matter is discharged from the bottom of the separation cylinder, while the water is raised from the center of the separation cylinder and sent out from the upper part of the main body, so that solids such as sand and dust mixed in the cooling water are provided. The object can be easily separated from the water, and the maintenance work for discharging the solid substance can be facilitated.

  According to the cooling tower sterilization mechanism of the present invention, a purification circulation path is provided separately from the circulation path for supplying cooling water to the air conditioning mechanism, and the cooling water passing through the circulation path is partially branched in this purification circulation path. Incorporating it, the photocatalytic device can sterilize and purify the entire cooling water flowing through the circulation path by reducing the burden of sterilization and purification action and returning the purified water to the cooling tower cyclically. In addition, the cooling water can be efficiently purified without increasing the size of the device disposed in the purification circulation path such as the photocatalyst device.

(Cooling system configuration)
FIG. 1 is an explanatory diagram showing the overall configuration of a cooling system including a cooling tower sterilization mechanism according to the present invention.
The cooling system shown in the figure includes a cooling tower 10, a circulation pump 20 connected to the cooling tower 10 by piping, and a heat exchanger 22 as a circulation path for cooling water used in the air conditioning mechanism. The cooling tower 10 has a configuration in which a fan 12 and a water sprinkling unit 14 are provided in the upper part and a water tank 16 is provided in the lower part.

  In this circulation path, the water cooled in the cooling tower 10 is sent to the heat exchanger 22 by the circulation pump 20, and the water that has passed through the heat exchanger 22 and the piping returns to the cooling tower 10 and is cooled and circulated again. In the cooling tower 10, water is sprinkled downward from the water sprinkling unit 14, and an air flow is generated from the bottom to the top by driving the fan 12. The water sprinkled from the water sprinkling unit 14 is partially vaporized and cooled by the heat of vaporization. Thus, the water is cooled each time it passes through the cooling tower 10 and is sequentially circulated. Since water evaporates and gradually dissipates in the cooling tower 10, tap water or the like is supplied as necessary. The configuration of these circulation paths is not fundamentally different from the conventional configuration.

(Structure of sterilization mechanism)
The cooling tower sterilization mechanism, which is characteristic in the present invention, has a purification circulation path that partially takes in and circulates cooling water that passes through the cooling tower 10 separately from the circulation path that is supplied to the air conditioning mechanism that passes through the heat exchanger 22. It is formed by disposing a sterilization mechanism using a photocatalyst in this purification circulation path.
That is, a pump 30 that allows water to flow through the purification circulation path via the pipe 31 and the valve 32 is connected to the water tank 16 of the cooling tower 10, and a separator 34 is connected to the outlet side of the pump 30. The photocatalyst device 36 is connected to the outlet side, and the delivery port of the photocatalyst device 36 and the water sprinkling part 14 of the cooling tower 10 are connected by piping.

The separator 34 is for separating solids brought in from the outside, such as dust and sand, from water taken from the water tank 16 into the purification circulation path. In the present embodiment, the separator 34 uses a centrifugal separation action. The separator 34 is used to separate the solid matter. The separator 34 (trade name Laval separator) used in the present embodiment is such that water fed from the upper part of the main body moves in the separation cylinder at high speed, and the solid matter is separated from the water while hitting the wall surface of the separation cylinder. The solids settle at the bottom of the separation cylinder, while the solid-free water rapidly rises at the center of the separation cylinder and is discharged outside from the top of the separation cylinder. Make.
The solid matter accumulated in the lower part of the separation cylinder is discharged together with water by opening and closing the on-off valve 34a on a regular basis.

  The separator 34 that rotates the water in the separation cylinder and separates the solid and the liquid using centrifugal force uses a filter sand or a filter for filtering, compared to a method using a sand filter or a cartridge filter. Compared to a separation mechanism that uses a filter, it is possible to reduce the size of the device, and the maintenance work is much simpler than the work of cleaning the filter sand or replacing the filter. This is advantageous.

In the air-conditioning mechanism using the open type cooling tower 10, when the fan 12 is driven, outside air inevitably flows into the cooling tower 10, so it is inevitable that dust, sand, and the like enter the cooling water together with the outside air. The reason why bacteria are propagated in this air conditioning system or algae are generated to cause water pollution is that bacteria are brought in along with sand and dust brought in from the outside.
In order to separate the sand and dust from the water by providing the separator 34 in the purification circulation path, first, solids such as sand and dust are removed from the water flowing into the photocatalytic device 36, and the photocatalytic action by the photocatalytic device 36 is performed. This is to ensure that this works effectively. In the photocatalyst device 36, if the surface of the photocatalyst material is contaminated, the catalytic action is not sufficiently effective. Therefore, separating solids such as sand and dust by the separator 34 is important for effective photocatalytic action.

FIG. 2 shows an internal configuration of the photocatalytic device 36 used in the present embodiment.
As shown in the figure, the photocatalyst device 36 of the present embodiment is provided with a device body 36a formed in a cylindrical body standing vertically, and an inflow port 37a of water to be treated is provided at the lower portion of the device body 36a. The upper part of the apparatus main body 36a is provided with an outlet 37b, and the water to be treated that flows into the apparatus main body 36a from the inlet 37a moves upward from the lower part of the apparatus main body 36a and flows out of the outlet 37b. Has been.

  Inside the apparatus main body 36a, support shelves 40a, 40b, 40c formed in a net shape for supporting the photocatalyst material 38 are installed in three stages at predetermined intervals in the vertical direction. The photocatalyst material 38 is formed in a spherical shape (15 mm diameter), and is flattened up and down so as to cover the entire surface of the support shelves 40a, 40b, and 40c on the respective support shelves 40a, 40b, and 40c. It arranges so that it may overlap in about two steps.

Ultraviolet lamps 42a, 42b, and 42c are disposed at intermediate positions in the height direction of the respective support shelves 40a, 40b, and 40c. These ultraviolet lamps 42a, 42b, and 42c are arranged to extend horizontally from the side wall of the apparatus main body 36a toward the opposite wall surface as shown in the figure. In the embodiment, the direction of the ultraviolet lamp 42b disposed in the middle is opposite to that of the other ultraviolet lamps 42a and 42c so that the photocatalyst material 38 is uniformly irradiated with ultraviolet rays.
By arranging the ultraviolet lamps 42a, 42b at the intermediate positions in the height direction of the support shelves 40a, 40b, 40c, the photocatalysts supported by the upper and lower support shelves 40a, 40b, 40c from these ultraviolet lamps 42a, 42b. Both materials 38 are irradiated with ultraviolet rays.
Ultraviolet light attenuates when it reaches 15 cm to 20 cm or more in water. In this embodiment, the distance between the ultraviolet lamps 42a, 42b, 42c and the support shelves 40a, 40b, 40c is set to be 15 cm to 20 cm. The ultraviolet lamps 42a, 42b, and 42c are controlled to be turned on by the control unit 44.

  One characteristic configuration of the photocatalytic device 36 of the present embodiment is a configuration of a photocatalytic material 38 that exhibits catalytic action. As described above, the spherical photocatalyst material 38 is used in this embodiment. The catalyst material actually used is a titanium catalyst material based on alumina. This titanium catalyst material collides titanium fine particles with the surface of an alumina substrate formed by spherical firing at a speed close to the speed of sound, and the titanium fine particles are oxidized when the collision energy at the time of collision is converted into thermal energy. It is formed by depositing on the surface of an alumina substrate as titanium (Japanese Patent Laid-Open No. 2002-316056).

  This titanium catalyst material is provided with a stable film of titanium oxide on the surface of the catalyst material and an “oxygen-deficient gradient structure” in which the bond with oxygen is slightly depleted as it enters the inside from the surface of the film. Therefore, titanium oxide, which has a semiconducting metal catalytic action, is catalyzed by ultraviolet light near 270 nm, while it is also catalyzed by light having a wavelength longer than this. Has characteristics. Thereby, it has stronger sterilization action and organic substance decomposition action. The organic substance decomposing action by the photocatalyst is an action in which a hydroxyl radical (OH radical) generated by the photocatalytic action breaks the C—H bond and N—H bond of the organic substance and decomposes into carbon dioxide gas and water, nitrogen gas and water.

Further, the titanium catalyst is formed as a sphere having a smooth surface (smooth), water flows uniformly, and the surface of the catalyst material is less likely to be contaminated. Further, the titanium oxide film deposited on the surface of the catalyst material is difficult to peel off and has a long life.
Some photocatalyst materials are formed by depositing titanium oxide on a base material with a binder, a paint, and an adhesive. Since the above titania catalyst material is deposited with titanium oxide exposed to the alumina base material without using a binder, water and catalytic action act directly and effectively compared to the case where a binder is used, Moreover, it has the advantage that it is hard to peel and to deteriorate easily.

(Operation of sterilization mechanism)
Then, the effect | action of the sterilization mechanism of the cooling tower mentioned above is demonstrated.
As shown in FIG. 1, the cooling tower sterilization mechanism takes in the water accumulated in the water tank 16 of the cooling tower 10 into the purification circulation path, sterilizes and purifies the water by the photocatalyst device 36, and returns it to the cooling tower 10. The circulation of water is performed by the action of sucking water from the water tank 16 by the pump 30 and sending it to the separator 34 and the photocatalyst device 36. A flow meter 50 is provided at the outlet of the photocatalyst device 36 to detect the flow rate in the purification circulation path.

As described above, the separator 34 separates and removes solids such as sand and dust contained in the cooling water, and the photocatalytic device 36 sterilizes (sterilizes) water by a catalytic action.
The sterilizing action of water in the photocatalyst device 36 is such that the water flowing into the device main body 36a of the photocatalyst device 36 contacts the photocatalyst material 38 supported by the support shelves 40a, 40b, and 40c while gradually rising in the device main body 36a. However, the photocatalytic material 38 is sterilized by the photocatalytic action. The photocatalyst material 38 is excited by the ultraviolet lamps 42a, 42b, and 42c so that the catalytic action is exhibited. Since the support shelves 40a, 40b, and 40c are formed in a net shape, the water moves so as to sew the gap between the mesh of the support shelves 40a, 40b, and 40c and the photocatalyst material 38 that is formed in a spherical shape, and the photocatalyst material 38 It is sterilized by contact with.

In the sterilization mechanism of this embodiment, the solid matter is separated and removed by the separator 34 so that foreign matter is not brought into the photocatalyst device 36 as much as possible, so that the surface of the photocatalyst material 38 is prevented from being contaminated. It is possible to prevent the photocatalytic action of the material 38 from deteriorating. Further, by preventing dirt from adhering to the surfaces of the ultraviolet lamps 42a, 42b, and 42c, it is possible to prevent the efficiency of the ultraviolet lamps 42a, 42b, and 42c from deteriorating.
Further, in this embodiment, the use of a titanium catalyst material having a smooth surface as the photocatalyst material 38 can further prevent the surface of the photocatalyst material 38 from being contaminated. The sterilization action works more effectively.

  Sterilization and sterilization using a photocatalyst material do not use chemicals and do not have any adverse effect on water. Therefore, it is completely problematic to return the sterilized water through the purification circulation path to the cooling tower 10. There is an advantage that it can be used without any problems. The water that has passed through the photocatalyst device 36 and returned to the cooling tower 10 is mixed with the water that has returned through the air conditioning mechanism, and is circulated as water used in the air conditioning mechanism. In the above embodiment, the water that has passed through the photocatalytic device 36 is returned to the sprinkler 14, but it may be simply returned to the water tank 16. In any case, it is preferable that the water returned via the purification circulation path is mixed with the water returning from the circulation path on the main pipe side.

  In the present embodiment, the purification circulation path takes in a part of the cooling water used in the air conditioning mechanism and sterilizes and purifies it. The cooling water flowing through the circulation path supplied to the air conditioning mechanism is directly supplied to the photocatalyst device 36. It is not configured to pass through and purify. However, if the cooling water flowing through the circulation path (main pipe) is partially taken in and sterilized, sterilized and returned continuously, the cooling water flowing through the circulation path and the purification circulation path As a whole, it is gradually sterilized, sterilized and purified.

  The flow rate at which the sterilization and purification capability of the photocatalyst device functions effectively is limited, and if a photocatalyst device that purifies by passing the flow rate through the circulation path as it is, an extremely large device is required, which is not realistic. . When using a photocatalytic device that is not so large as a photocatalytic device and can be used within the range that can effectively exhibit sterilization and purification ability by photocatalytic action, a purification circulation route is provided separately from the circulation route as in this embodiment. It is effective to purify the entire cooling water combined with the circulation path by suppressing the flow rate in the purification circulation path to a flow rate at which the photocatalytic action can sufficiently act and returning the sterilized and purified water from the purification circulation path to the cooling tower 10. Become.

  It takes a certain number of days to purify the entire cooling water combined with the circulation path, but after the entire cooling water has been purified to a certain level, it is always sterilized and purified by the purification circulation path. It is easy to maintain a constant purification level. As described above, the method of purifying cooling water using a photocatalyst has the advantage that it does not have any adverse effect on the circulation system of the air-conditioning mechanism, compared with the method of using chemicals or the method of using ozone gas. There is.

Below, the test example which purified the cooling water of the air-conditioning mechanism actually using the cooling tower sterilization mechanism of the said embodiment is demonstrated.
The water purification capacity was tested by installing the cooling tower sterilization mechanism in the existing cooling tower air conditioning mechanism (fourth year old) and measuring how the Legionella count in the cooling water changes. .
The cooling tower used in the test has a cooling capacity of 365 refrigeration tons, a water capacity of the cooling water system of 5.5 cubic meters, and a cooling water circulation flow rate of 290 (cubic meters / h) h. The sterilization mechanism is a photocatalytic device power consumption of 24 W (100 V) and a water circulation flow rate of 10 (cubic meter / h).

The cooling tower was operated continuously for 24 hours, and the sterilization mechanism was also operated continuously to observe the progress.
FIG. 3 is a graph showing how the number of Legionella bacteria in the cooling water has changed. The first sampling (1)) is the number of Legionella bacteria at the time when the water was replaced at the start of the test (22,000 CFU / 100 ml). The second sampling (2)) was 13 days later, and at this point, the Legionella count was already negative. The third sampling (3)) was further two days later, at which time the number of Legionella bacteria was 100,000 or more (CFU / 100 ml). The increase in the number of Legionella bacteria in this way is due to peeling of the biofilm (amoeba) that lived in the pipes and contact materials when the cooling water in the system was replaced with treated water by photocatalyst. It is inferred that the Legionella bacteria had appeared at once. This is because the water treated by the sterilization mechanism has the ability to sterilize and decompose so that the biofilm in the system can be peeled off, and because the system is physically clean, This is considered to indicate that the state became inappropriate (insufficient organic matter).

As a result of measuring by collecting water (4) 12 days after the Legionella count increased at a stroke, the Legionella count decreased to 40 (CFU / 100 ml). From this, it is considered that the entire cooling water can be sterilized and purified in about two weeks in the apparatus of the test example. In this experiment, as an emergency measure, the whole cooling water was replaced with fresh water (tap water) at this point, and the test was continued.
Thereafter, water was collected three times every 14 days (5), 6), 7)), and finally one month later (8)). In each of the water collections 5) to 8), the Legionella count was negative.

In addition, the internal state of the photocatalytic device was observed at the time of sampling 4) to 5) and at the time of sampling 8). At the time of sampling 4) to 5), the inside of the apparatus was dirty with dirt, but the inside was not cleaned and left as it was. At the time of sampling 8), when the inside of the apparatus was observed, the previous sludge and other dirt were gone. Some sand was observed on the support shelf. This indicates that the overall purification degree of the cooling water has progressed with time.
Moreover, about the state of the algae adhering to a flow meter, algae adhered to the flow meter in about one week after the test started, and it became difficult to read the indicated value of the flow meter. The flow meter is of a flow cell type and has a flow cell accommodated in a glass tube. At the time of sampling 4) to 5), the flowmeter was cleaned, and the indicated value at that time was 7 (cubic meter / h), so it was adjusted to 10 (cubic meter / h). At this time, after cleaning the flow meter, no algae adhered to the flow meter until the end of the test, and the cooling water was kept clean.

  In addition, the guideline value of the flowmeter at the time of sampling 8) was lowered to 5 (cubic meter / h). This is thought to be because the cooling tower load was reduced and the pump speed was reduced by inverter control. When the cooling water is purified, dirt in the heat exchanger is also removed together with this, so that heat transfer efficiency is increased, and dirt is also removed from the contact material in the cooling tower, thereby increasing the heat transfer efficiency. From this, it is considered that the energy saving effect of the air conditioning mechanism as a whole is also expected.

The above test results show that the method of branching the cooling water from the cooling tower 10 and sterilizing using the photocatalytic device 36 is sufficiently effective as a method for sterilizing Legionella bacteria. The fact that the negative state of Legionella persisted after the sterilization effect was exhibited has no effect on the sterilization environment in the system even if the cooling water inflow to the sterilization mechanism is slightly reduced. It is shown that the method of sterilization and circulation is effective in maintaining a clean environment in the system. Since this method uses a method in which the treated water is partially introduced into the sterilization mechanism, purified and returned to the circulation path of the air conditioning mechanism, it takes time until the entire cooling water is purified (replaced with treated water). . In the above test, the entire cooling water was replaced with the treated water in about two weeks, which depends on the amount of the cooling water in the entire air conditioning mechanism and the treatment capacity of the sterilizing mechanism.
In a system in which cooling water is always circulated and used like a cooling tower, the cooling water partially flows into the sterilization mechanism and is sterilized and purified as in the present invention. Therefore, it is extremely effective as a method for effectively sterilizing and purifying the capacity of the photocatalytic device without increasing the size of the photocatalytic device.

It is explanatory drawing which shows the whole structure of the air-conditioning mechanism containing the sterilization mechanism of the cooling tower which concerns on this invention. It is explanatory drawing which shows the internal structure of a photocatalyst apparatus. It is a graph which shows the change of the number of Legionella bacteria of cooling water in a test example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cooling tower 12 Fan 14 Sprinkling part 16 Water tank 20 Circulation pump 22 Heat exchanger 30 Pump 34 Separator 36 Photocatalyst apparatus 36a Apparatus main body 38 Photocatalyst material 40a, 40b, 40c Support shelf 42a, 42b, 42c Ultraviolet lamp 50 Flowmeter

Claims (4)

A cooling tower sterilization mechanism used for sterilization and purification of cooling water of an air conditioning mechanism including an open type cooling tower,
Separately from the circulation path that circulates and supplies the cooling water to the heat exchanger of the air conditioning mechanism via the cooling tower, the cooling water is partially taken from the cooling tower, and the cooling water is supplied to the cooling tower via the photocatalyst device. Provide a separate purification circulation path to circulate and return,
A pump for circulating cooling water in the purification circulation path to the purification circulation path;
A separator that is disposed upstream of the photocatalyst device and separates solid matter mixed in the cooling water;
In the photocatalyst device, a photocatalyst material formed in a spherical shape is arranged on a support shelf arranged at a predetermined interval, and an ultraviolet lamp for irradiating the photocatalyst material with ultraviolet rays is arranged in the middle of the support shelf. Cooling tower sterilization mechanism.   The said purification circulation path is made into the piping structure which takes in cooling water from the water tank of the said cooling tower, and returns the cooling water after passing the said photocatalyst apparatus to the watering part of the said cooling tower. Cooling tower sterilization mechanism. The photocatalyst material is
Titanium fine particles collide with the surface of an alumina base material made of alumina formed into a spherical shape at a speed close to the speed of sound, and when the collision energy at the time of collision is converted into thermal energy, the titanium fine particles become titanium oxide as the alumina base material. The sterilization mechanism for a cooling tower according to claim 1, wherein the sterilization mechanism is a titanium catalyst material deposited on the surface of the steel plate and formed on a smooth surface. The separator is
The cooling water fed from the upper part of the main body formed in the separation cylinder rotates and moves at high speed along the inner wall surface of the separation cylinder, so that the solid liquid is separated by centrifugal force, and the solid matter is separated from the separation cylinder. The sterilization of a cooling tower according to any one of claims 1 to 3, wherein the cooling tower has a configuration in which water is discharged from the bottom while the water is raised from the center of the separation cylinder and is sent out from the upper part of the main body. mechanism.

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