Water treatment method for auxiliary cooling device of air-cooled condenser

Abstract

To provide a water treatment method for an auxiliary cooling device of an air-cooled condenser, which ensures a location in a circulation path for replenishing a water treatment agent and maintains a constant concentration of a water treatment agent in circulating water by a simple method at a low cost.SOLUTION: There is provided a water treatment method for an auxiliary cooling device of an air-cooled condenser including: a water-retaining material 41 that lowers a temperature of air; a storage tank 42 that stores circulating water; circulating means 45 for circulating the circulating water between the water-retaining material 41 and the storage tank 42; circulating water discharge means 46 for discharging a part of the circulating water outside a circulation path 47; water replenishment means 43 for replenishing water to the circulating water; and water treatment agent replenishment means 44 for supplying a water treatment agent to the circulating water. The method includes: replenishing the water treatment agent by the water treatment agent replenishment means 44 after a part of the circulating water is discharged outside the circulation path 47 by the circulating water discharge means 45, and at the same time replenishing water by the water replenishment means 43.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a water treatment method for an auxiliary cooling device of an air-cooled condenser, which prevents the generation of slime by supplying a water treatment agent to the circulating water in the auxiliary cooling device. [Background technology]

[0002] The currently used auxiliary cooling devices for condensers are devices that supply water to a water-retentive material installed on the windward side of the condenser of the outdoor unit, and use the latent heat generated when the water evaporates to lower the temperature of the air taken into the condenser. A typical auxiliary cooling device is configured to circulate water by supplying it from above the water-retentive material, and the water that flows out from below the material is supplied again from above the material.

[0003] However, Legionella bacteria may occur and form slime when the auxiliary cooling device uses circulating water for a long period of time. This slime deteriorates the appearance and further clogs the water-retaining material, and reduces the operating efficiency of the chiller as the amount of air supplied decreases. In addition, the generation of Legionella bacteria and their scattering to the surroundings may cause health damage. In order to suppress Legionella bacteria, it is possible to supply chlorine-sterilized water such as tap water. However, this alone is not effective enough for sterilization. Therefore, in the past, measures against Legionella bacteria have been taken by cleaning and replacing the water-retaining material. However, there is a problem in that the cleaning and replacement are laborious and costly. In addition, because the auxiliary cooling device is installed outdoors, dust particles from the outside air become trapped in the circulating water. The water supplied to the water-retentive material not only evaporates in the material, but also evaporates while circulating, so impurities such as silica, calcium, and magnesium contained in the water become concentrated. In addition, metal ions contained in the circulating water may become concentrated and exceed their solubility, resulting in the deposition of metal oxides (scale) on the auxiliary cooling device. These also pose problems such as the large effort and cost required to clean and replace the auxiliary cooling device.

[0004] In response to this, Patent Document 1 discloses an auxiliary cooling device for a condenser that includes a surveillance camera for monitoring the circulating water, or a drainage pump or solenoid valve provided in the drainage flow path, and a control unit that periodically operates the drainage pump or solenoid valve to drain water from the drainage flow path. This makes it possible to manage the circulating water without visiting the site. Patent Document 2 discloses an auxiliary cooling system for a condenser that is equipped with splash prevention means for preventing splashes from splashing downwind from the contact surface of the side of the water-retentive material. This prevents water stains and scale from adhering to the surface of the heat dissipation fins even when the system is operated for a long period of time, and prevents a decrease in heat exchange efficiency during air-cooling operation. However, in Patent Documents 1 and 2, when Legionella bacteria are generated and slime or scale is formed, the auxiliary cooling device must be replaced, and the problems of the labor required for replacement work and the generation of waste material are not solved. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-018045 [Patent Document 2] JP 2020-029982 A Summary of the Invention [Problem to be solved by the invention]

[0006] Up until now, in the auxiliary cooling device for the condenser, the device itself is small and lightweight, and the amount of circulating water is relatively small, so measures against the generation of slime and scale have not been considered. However, as a measure against the generation of slime, etc., there is water treatment technology in an open circulating cooling water system used in a cooling tower, which has a relatively large amount of circulating water. In the open circulating cooling water system, water treatment is carried out by supplying water treatment agents such as hypochlorite to the circulating water. However, these technologies could not be applied directly to the auxiliary cooling device.

[0007] In water treatment in an open circulation cooling water system used in a cooling tower, the water treatment agent is supplied to the piping of the cooling water system or to the cooling tower pit. However, when the water treatment agent is supplied to the piping, the amount of evaporation is large and the retention time is short in the circulation path of the auxiliary cooling device compared to the cooling tower in the open circulation cooling water system. Therefore, it is necessary to dissolve the water treatment agent supplied in the circulating water as quickly as possible throughout the entire circulation path. Therefore, although it is optimal to supply the water treatment agent to the piping that supplies water, in the case of the auxiliary cooling device of the condenser, there is a problem that the piping that supplies water is thin and it is not possible to provide a supply point. In addition, when replenishing the water treatment agent in the pit that constitutes the auxiliary cooling device for the condenser, the capacity of the pit directly below the water-retaining material is small, making it impossible to ensure a place to refill the water treatment agent. Furthermore, there is also the problem that the water-retaining material (usually made of paper) can be damaged when the water treatment agent adheres to it before being mixed with the circulating water.

[0008] Examples of methods for replenishing water treatment agents in water treatment in an open circulation cooling water system used in a cooling tower include a method of continuously measuring the concentration of the water treatment agent and controlling the amount of water treatment agent replenished so that the concentration is uniform, a method of replenishing the water treatment agent by timer control, and a method of replenishing the water treatment agent in proportion to the amount of water to be replenished. However, it may not be appropriate to apply existing water treatment agent replenishment methods as they are to the auxiliary cooling device of a condenser. For example, continuously measuring the concentration of the water treatment agent and controlling the amount of water treatment agent replenished so that the concentration is uniform requires an expensive device for continuously measuring the concentration of the water treatment agent, and in particular, the auxiliary cooling device of the condenser is a small and relatively inexpensive device, which causes a problem of poor cost performance. Furthermore, the method of replenishing the water treatment agent in proportion to the amount of water to be replenished requires expensive equipment to make the amount proportional to the amount of water, and in particular, the auxiliary cooling device for the condenser is a small and relatively inexpensive device, resulting in a problem of poor cost performance. In addition, when replenishing water treatment agents by timer control, in order to keep the concentration of water treatment agents in the circulation path constant, a method is adopted in which the amount of water discharged to keep the water quality constant is estimated from the amount of evaporated water estimated by the chiller operation time and load factor in a general open cooling tower, and the water treatment agent is replenished at timer-controlled intervals. However, in order to estimate the amount of evaporated water in the auxiliary cooling device of the condenser, it is necessary to consider the wet-bulb temperature of the atmosphere in addition to the chiller operation time and load factor. For this reason, it is not possible to estimate the amount of evaporated water or the amount of water discharged to keep the water quality constant, and there is a problem that it is difficult to keep the concentration of water treatment agents in the circulation path constant when replenishing water treatment agents by timer control.

[0009] In view of the above problems, an object of the present invention is to provide a water treatment method for an auxiliary cooling device of an air-cooled condenser, which provides a place for replenishing a water treatment agent in a circulation path by a low-cost and simple method, and maintains a constant concentration of the water treatment agent in the circulating water. [Means for solving the problem]

[0010] The features of the embodiments of the present invention will be listed and described below. (1) A water treatment method for an auxiliary cooling device of an air-cooled condenser comprising: a water-retaining material provided on the windward side of an air-cooled condenser, through which circulating water containing a water treatment agent and water is circulated and which lowers the temperature of the air taken into the condenser by the latent heat generated when the circulating water evaporates; a storage tank for storing the circulating water; a circulation means for circulating the circulating water between the water-retaining material and the storage tank; a circulating water discharge means for discharging a portion of the circulating water out of a circulation path when circulation of the circulating water is stopped; a water supply means for supplying the water in the circulating water; and a water treatment agent supply means for supplying the water treatment agent in the circulating water, wherein the water treatment method comprises supplying the water treatment agent by the water treatment agent supply means after a portion of the circulating water has been discharged out of the circulation path by the circulating water discharge means and simultaneously with supplying the water by the water supply means. (2) The water treatment method for an auxiliary cooling device of an air-cooled condenser according to (1), wherein the water treatment agent is replenished into the storage tank. (3) The water treatment method for an auxiliary cooling device of an air-cooled condenser according to (1) or (2), wherein the water treatment agent replenished by the water treatment agent replenishment means is an amount calculated from the amount of the circulating water discharged by the circulating water discharge means. (4) The water treatment method for an auxiliary cooling device of an air-cooled condenser according to (1), (2), or (3), wherein a supply position of the water treatment agent by the water treatment agent supply means is provided downstream of a supply position of the water by the water supply means. Effect of the Invention

[0011] According to the present invention, it is possible to provide a water treatment method for an auxiliary cooling device of an air-cooled condenser, which ensures a location for replenishing a water treatment agent in a circulation path and maintains a constant concentration of the water treatment agent in the circulating water. Furthermore, according to the present invention, since no measuring equipment or flowmeter is required, a low-cost and simple water treatment method for an auxiliary cooling device of an air-cooled condenser can be provided. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic diagram showing the configuration of an auxiliary cooling device for implementing the water treatment method for an auxiliary cooling device of an air-cooled condenser of the present invention. FIG. [Diagram 2] FIG. 2 is a schematic diagram showing a normal operation state of an auxiliary cooling device for implementing the water treatment method of the auxiliary cooling device of an air-cooled condenser of the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing a state when the circulation means of the auxiliary cooling device for implementing the water treatment method of the auxiliary cooling device of the air-cooled condenser of the present invention is stopped. [Figure 4] FIG. 2 is a schematic diagram showing a state when the circulation means of the auxiliary cooling device for implementing the water treatment method of the auxiliary cooling device of the air-cooled condenser of the present invention is restarted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following description is merely an example of an embodiment of the present invention, and does not limit the scope of the claims.

[0014] <Configuration of auxiliary cooling device> FIG. 1 is a schematic diagram showing the configuration of an auxiliary cooling device for carrying out the water treatment method of the present invention for an auxiliary cooling device of an air-cooled condenser. As shown in Fig. 1, a refrigerator 1 equipped with an air-cooled condenser 2 and an auxiliary cooling device for the air-cooled condenser (hereinafter simply referred to as "auxiliary cooling device") 4 are installed inside the refrigerator 1. Condenser 2 is broadly classified into air-cooled and water-cooled types, but this application applies to the air-cooled type that uses air. The auxiliary cooling device 4 includes a water-retaining material 41 that contains circulating water that contains a water treatment agent and water and cools the delivered air, a storage tank 42 that stores the circulating water, and a circulation means 45 that supplies the circulating water. In addition, the auxiliary cooling device 4 includes a circulation path 47 that communicates the water-retaining material 41, the storage tank 42, and the circulation means 45, and circulates the circulating water.

[0015] The refrigerator 1 has at least a condenser 2 disposed therein, and a cooling fan 11 provided on the upper portion of the refrigerator 1. The cooling fan 11 may be provided at a position facing the condenser 3. Although not shown, the refrigerator 1 also includes an evaporator, a compressor, an expansion valve, etc. The refrigerator 1 is provided with an evaporator, and cooling water is circulated between the evaporator and a condenser 2.

[0016] In the chiller 1, the condenser 2 circulates the cooled cooling water through the circulation means 45. The cooled and condensed cooling water is introduced into the evaporator. A heat-donating fluid warmed by a load that generates heat, such as a chemical plant or a power plant, is transported to the evaporator. At this time, heat is exchanged between the cooled cooling water of the condenser 2 and the warmed heat-donating fluid of the evaporator. As a result, the warmed cooling water is transported to the condenser 2, where it is cooled and reused. The cooled heat-donating fluid is also transported to the load to operate the plant. Therefore, cooling the cooling water by the condenser 2 of the chiller 1 is important for the operation of the plant. This is because the lower the temperature of the air blown to the chiller 1 for cooling, the higher the operating efficiency of the plant can be. Therefore, an auxiliary cooling device 4 is provided to lower the temperature of the air to be blown before blowing to the chiller 1.

[0017] The water-retaining material 41 in the auxiliary cooling device 4 is provided on the windward side of the condenser 2 of the refrigerator 1. The arrows in FIG. 1 indicate the movement of the wind. The water-retaining material 41 is supplied with circulating water by sprinkling it from the water-spraying section 472 at the top. As the circulating water absorbed in the water-retaining material 41 gradually flows downward, the circulating water evaporates while taking heat from the air passing through the water-retaining material. At the same time, the temperature of the circulating water also drops. The air temperature drops as it passes through the water-retaining material 41 containing the circulating water whose temperature has been lowered. The circulating water whose temperature has been lowered is also collected in the pit section 473 provided at the bottom of the water-retaining material 41. Furthermore, this circulating water is collected and stored in the storage tank 42. In addition, since the auxiliary cooling device 4 has a large amount of circulating water that evaporates and the circulating water is rapidly reduced, the frequency of replenishment of circulating water and the amount of replenishment water are increased. The water-retaining material 41 is made of any of paper, resin fibers such as polyethylene, glass fibers, etc.

[0018] The storage tank 42 is also provided with water supply means 43 for supplying water in the circulating water, water treatment agent supply means 44 for supplying water treatment agent in the circulating water, circulation means 45 for circulating the circulating water, and circulating water discharge means 46 for blowing and discharging the circulating water. It is further provided with a circulation path 47 for supplying the circulating water from the storage tank 42 to the water retention material 41. The storage tank 42 is installed at the bottom of the circulation path 47. This allows the circulating water to be automatically returned to the storage tank 42 even if the circulation means 45 stops.

[0019] The water supply means 43 supplies make-up water either manually or automatically at a location in the storage tank 42 or the circulation path 47 . The water supply means 43 includes a supply tank 431 for storing the supply water, a supply pump 432 for supplying the supply water, and a supply mechanism 434 for automatically supplying the supply water by a ball tap or the like. By providing the supply mechanism 434, the supply water can be automatically replenished when the amount of water in the storage tank 42 falls below a predetermined amount. The supply mechanism 434 includes a ball tap as a float valve. This ball tap floats on the liquid surface and opens and closes by moving vertically according to the height of the liquid surface of the circulating water to supply make-up water.

[0020] The water treatment agent supply means 44 includes a water treatment agent tank 441 for storing the water treatment agent and a transport pump 442 for transporting the water treatment agent. The water treatment agent is not limited to being a solid or a liquid. The water treatment agent supply means 44 can supply the water treatment agent manually or automatically at any point in the storage tank 42 or the circulation path 47.

[0021] In addition, the circulation means 45 sends out the circulating water stored in the storage tank 42 to a circulation path 47 that communicates with the storage tank 42. The circulation path 47 is connected to the water retention material 41 and the storage tank 42 to form a water system that circulates the circulating water. A pump such as a centrifugal pump or a cascade pump can be used as the circulation means 45. Here, it is preferable to use a centrifugal pump as the circulation means 45.

[0022] Furthermore, the circulating water discharge means 46 can be provided in either the storage tank 42 or the circulation path 47. In the water treatment method for an auxiliary cooling device of the present invention, a pipe connected to a discharge outlet is provided at a certain height of the storage tank 42 as the circulating water discharge means 46. This makes it possible to discharge the circulating water so as to keep the amount of circulating water in the auxiliary cooling device 4 constant, without having to measure the amount of the circulating water. Furthermore, a drainage pump immersed in the circulating water can also be used as the circulating water discharge means 46.

[0023] The circulation path 47 forms a path for circulating the circulating water. The circulating water sent out from the storage tank 42 is supplied to the sprinkling section 472 through a supply pipe 471, which is a part of the circulation path 47. The sprinkling section 472 sprinkles the circulating water on the water-retaining material 41. As the circulating water flows down the water-retaining material 41, a part of the water vaporizes and cools the circulating water. The remaining circulating water is collected in the pit section 473, passes through the receiving pipe 474, and is stored in the storage tank 42. At this time, a mechanism for removing impurities can be provided midway from the receiving pipe 474 to the storage tank 42. Examples of impurities include scale, metal ions, slime, and other soil and sand brought in from the atmosphere.

[0024] <Auxiliary cooling device operation> Next, an example of the operation of an auxiliary cooling system for carrying out the water treatment method of the present invention for an auxiliary cooling system of an air-cooled condenser will be described.

[0025] FIG. 2 is a schematic diagram showing a state during normal operation of an auxiliary cooling system for carrying out the water treatment method of the present invention for an auxiliary cooling system of an air-cooled condenser. During normal operation, as shown in Figure 2, the circulation means 45 is operating, water is supplied from the circulation path 47 to above the water retention material 41, and water flowing out from below the water retention material 41 is returned to the storage tank 42 by the circulation path 47.

[0026] In the auxiliary cooling device 4, 10 to 50% of the amount of circulating water evaporates when the circulating water circulates once. This is because the amount of water that evaporates in the water retaining material 41 is large. In a general cooling tower, the amount of water that evaporates when the circulating water circulates once is only about 0.1 to 1% of the amount of circulating water. In addition, in the auxiliary cooling device 4, the water storage capacity of the storage tank 42 is small compared to the total amount of water in the circulation path 47. This is because the ratio of the water storage capacity of the storage tank 42 to the total amount of retained water used for the circulating water of the auxiliary cooling device 4 (water storage capacity of the storage tank / total amount of retained water) is relatively small at 0.2 to 0.4%, whereas in a general cooling tower, it is 0.4 to 0.6%. If the amount of circulating water is small, the time for the concentration of impurities such as slime and scale contained in the circulating water to increase is shortened due to water evaporation. For this reason, in order to prevent overconcentration of impurities contained in the circulating water, it is necessary to periodically discharge the circulating water to the outside of the circulation path 47 and replace the water. The method of replacing the circulating water is not particularly limited, but by stopping the circulation means 45, an amount of circulating water exceeding the storage capacity is discharged from the storage tank 42, and the amount of circulating water after discharge and the amount of make-up water are kept constant each time.

[0027] FIG. 3 is a schematic diagram showing a state when the circulating means of the auxiliary cooling device for carrying out the water treatment method of the present invention for an auxiliary cooling device of an air-cooled condenser is stopped. By stopping the circulation means 45, the circulating water is returned to the storage tank 42, and the amount of stored water increases, as shown in Fig. 3. At this time, the water level in the storage tank 42 rises, and when it reaches the height of the circulating water discharge means 46, the circulating water is discharged from the circulating water discharge means 46.

[0028] FIG. 4 is a schematic diagram showing a state when the circulation means of the auxiliary cooling device for carrying out the water treatment method of the auxiliary cooling device of the air-cooled condenser of the present invention is restarted. Because the circulating water in the storage tank 42 starts circulating again, the amount of circulating water in the storage tank 42 decreases. As shown in Fig. 4, water in the circulating water is replenished from the water replenishment means 43 to make up for the amount of circulating water, and at the same time, the water treatment agent in the circulating water is replenished from the water treatment agent replenishment means 43.

[0029] In the auxiliary cooling device 4, there are two patterns for the timing at which water is replenished. (1) When the water level in the storage tank 42 drops due to evaporation of circulating water. (2) After the concentration of impurities contained in the circulating water reaches a predetermined set value and the circulating water is discharged. When water is replenished in proportion to the amount of circulating water that has decreased, a water treatment method can be implemented in which the water treatment agent is replenished in conjunction with the replenishment of water, regardless of the timing of (1) or (2).

[0030] In the water treatment method of the present invention, the water treatment agent is not replenished at the timing (1) above, but is replenished only at the timing (2) above. At this time, the amount of water treatment agent replenished is determined by making the amount of water replenished proportional to the amount of water replenished, taking into consideration the amount of evaporation in the entire circulation path 47. For example, a measuring device is installed to measure the amount of make-up water replenished from the metering pump, and when 10 L of make-up water is replenished, 400 mg of water treatment agent is replenished by the metering feeder accordingly, so that the concentration of the water treatment agent per make-up water becomes 40 mg / L. In addition, when the water treatment agent is a liquid product, the metering pump that replenishes may be operated for a certain period of time. For example, when it is desired to maintain the water treatment agent concentration at 200 mg / L by managing the circulating water to be 5 times concentrated, the amount of water treatment agent replenished is 200 / 5=40 mg / L. When 40 mg / L of water treatment agent is replenished per make-up water, the concentration in the circulating water can be made 200 mg / L by operating the circulating water to be 5 times concentrated using this make-up water. On the other hand, in the water treatment method of the present invention, the water treatment agent is replenished in one lump according to the amount of water replenished after the circulating water is discharged, so the amount replenished is 200 mg / L. This means that, in response to the amount of evaporation, only the evaporated water is replenished, and no water treatment agent is replenished. Therefore, the amount of water treatment agent that has flowed out of the auxiliary cooling device 4 due to the circulating water being discharged can be replenished.

[0031] <Water treatment method: Water replenishment, water treatment agent replenishment> In the water treatment method of the present invention, it is preferable that the location where the water treatment agent is replenished is located downstream of the location where the water is replenished, and moreover, it is preferable that the location where the water treatment agent is replenished is located inside the storage tank 42, which has a large area and is easy to mix with the circulating water. This allows for easy mixing in a short time. Furthermore, since this is a location where the water treatment agent is sufficiently mixed with the circulating water, corrosion of the storage tank 42, the water retaining material 41, etc. can be kept low. In addition, in the water treatment method of the present invention, the water treatment agent is replenished after a portion of the circulating water is discharged. The amount of circulating water discharged by the circulating water discharge means 46 and the amount of water to be replenished are constant every time while the auxiliary cooling device 4 is operating, so the amount of the water treatment agent to be replenished is also constant every time. Therefore, a flowmeter for measuring the flow rate of the make-up water replenished from the water replenishment means 43 is not required. As a result, the amount of the water treatment agent to be replenished is calculated by converting the amount of the water treatment agent discharged at the same time from the amount of the circulating water discharged by the circulating water discharge means 46 to the amount of the water treatment agent discharged at the same time, and the required make-up amount of the water treatment agent is calculated. The calculated amount is replenished all at once when the make-up water to be replenished is supplied. In this case, it is desirable to replenish using a metering pump or a metering feeder. For example, if a measuring device is installed to measure the amount of make-up water replenished from the metering pump, and when 10 L of make-up water is replenished, 0.4 g of the water treatment agent is replenished by the metering feeder in accordance with that, the concentration of the water treatment agent per make-up water will be 0.04 g / L. In addition, if the water treatment agent is a liquid product, the metering pump to replenish may be operated for a certain number of seconds. As a result, the water treatment method of the present invention can maintain a constant concentration of the water treatment agent in the circulating water during operation of the auxiliary cooling device 4. In addition, since there is no need to install equipment for measuring the concentration of the water treatment agent in the circulating water, or flow meters for measuring the amount of water being replenished or the amount of water treatment agent being replenished, the installation costs for additional equipment can be reduced.

[0032] More specifically, the water treatment method for the auxiliary cooling device is as follows. In an open cooling water system, circulating water may be discharged relative to the amount of water held when water flow is stopped, and the ratio of the amount of discharged water to the amount of water held during operation (discharge ratio = amount of discharged water / amount of water held during operation) is about 0 to 10%. In the auxiliary cooling device 4 in the water treatment method of the present invention, a certain ratio of water is always discharged relative to the amount of water held when water flow is stopped. This discharge ratio is characterized by being 20% ​​or more, which is higher than that of a cooling tower. This is because the amount of discharged water is determined by the capacity of the storage tank 42, and the capacity of the storage tank 42 is small, about 20 to 30 L.

[0033] The discharge of circulating water in the auxiliary cooling device 4 is performed by stopping the circulation means 45 in the circulation path 47, causing the circulating water to accumulate in the storage tank 42 located at the bottom of the auxiliary cooling device 4, and discharging the excess water exceeding the tank's storage capacity outside the circulation path 47 by the circulating water discharge mechanism 46. By stopping the circulation means 45, only 20 L of circulating water (= storage capacity of the storage tank 42) remains in the storage tank 42, and the remaining approximately 20 L is all discharged. Since the capacity of the storage tank 42 is always constant and the amount of circulating water in the circulation path 47 can be set arbitrarily, the amount of water to be added as replenishment after discharge by the circulating water discharge means 46 can be set to a constant amount.

[0034] By utilizing this mechanism, the amount of water treatment agent to be replenished can be determined according to a preset amount of water to be replenished, without continuously measuring the amount of water to be replenished. The quality of the circulating water passing through the circulation path 47 is about 2 to 3 times that of the make-up water in terms of electrical conductivity. By discharging by the circulating water discharge means 46, 20% or more of this is discharged outside the circulation path 47, and when the same amount of water as that discharged after the circulation of the circulating water is replenished, the electrical conductivity drops significantly to about 1 to 2 times that of the make-up water. In such a case where the water quality of the circulating water changes significantly over time, continuous replenishment is difficult as a method of replenishing the water treatment agent because the concentration of the water treatment agent also changes significantly according to the change in water quality. Therefore, the concentration of the water treatment agent is set based on the make-up water, which has a nearly constant water quality, and the water treatment agent is replenished at the same time as the water is replenished. This makes it possible to control the concentration of the water treatment agent in the circulating water within a certain range.

[0035] The water treatment agent to be replenished may be in any form, whether liquid or solid. However, in the case of a solid water treatment agent, the method of supplying the water treatment agent to the circulation path 47 is not particularly limited, but a method of immersing the water treatment agent in the circulating water or a method of bringing a part of the water treatment agent into contact with the circulating water is preferable. In the case of a liquid water treatment agent, a method of using a tube pump, a method of using a bellows pump, a method of supplying the water treatment agent by gravity without using a transport pump, or the like is preferable.

[0036] Examples of water treatment agents include slime control agents and scale inhibitors. There is no particular restriction on the components of the water treatment agent, but an oxidizing agent is preferable, and a chlorine agent is particularly preferable. Furthermore, since free chlorine agents are highly corrosive and may damage the water retention material 41, it is more preferable that the water treatment agent contains combined chlorine.

[0037] Slime control agents are water treatment agents that suppress the sticky muddy dirt that accumulates in water supply and drainage facilities, equipment, and pipes due to Legionella bacteria. The intervals between doses are based on the period during which the bactericidal effect lasts, and vary depending on the concentration and the season of use. Slime control agents act on the surface of slime, reducing the number of Legionella bacteria and preventing them from adhering to and multiplying in pipes.

[0038] Examples of slime control agents include oxidizing agents such as sodium hypochlorite, calcium hypochlorite, dichloroisocyanuric acid, trichloroisocyanuric acid, sodium hypobromite, bromochlorodimethylhydantoin (BCDMH), monochlorosulfamic acid, etc. Also included are organic agents such as methylisothiazolinone (MIT), chloromethylisothiazolinone (Cl-MIT), dibromonitroethanol (DBNE), dibromonitrilopropionamide (DBNPA), etc. More specifically, but not limited to, 2,2-dibromo-3-nitrilopropionamide (DBNPA), 2,2-dibromo-2-nitroethanol (DBNE), 2-bromo-2-nitro-1,3-propanediol (BNP), orthophthalaldehyde (OPA), glutaraldehyde, 4,5-dichloro-1,2-dithiolan-3-one (dithiol), 1,4-bis(bromoacetoxy)-2-butene, 1,2-bis(bromoacetoxy)ethane, 2-methyl-4-isothiazolin-3-one or a metal salt thereof. , 5-chloro-2-methyl-4-isothiazolin-3-one or a metal salt thereof, 4,5-dichloro-2-octyl-4-isothiazolin-3-one, 1,2-benzisothiazolin-3-one, methylene bisthiocyanate, hexabromodimethyl sulfone, 3,3,4,4-tetrachlorotetrahydrothiophene-1,1-dioxide, dichloroglyoxime, 1-bromo-3-chloro-5,5-dimethylhydantoin, tetrakis-hydroxymethyl-phosphonium-sulfate, and the like.

[0039] Moreover, scale inhibitors are water treatment agents that remove water-insoluble oxides that have accumulated in water supply and drainage facilities, equipment, piping, etc. If they crystallize and adhere inside piping equipment, etc., they become very difficult to remove, causing problems in water supply and drainage.

[0040] Examples of the scale inhibitor include phosphates such as orthophosphoric acid, polymerized phosphoric acid, and phosphonic acid, acrylic acid polymers and copolymers, and maleic acid polymers and copolymers. More specifically, examples of the scale inhibitor include polymers having carboxylic acid units, phosphonic acid, and polyphosphates. Examples of the polymers having carboxylic acid units include homopolymers and copolymers of acrylic acid, methacrylic acid, maleic acid, and itaconic acid, and examples of the monomers copolymerized with these unsaturated carboxylic acids include vinyl sulfonic acid, styrene sulfonic acid, vinyl acetate, 2-hydroxyethyl methacrylate, and 2-hydroxy-3-allyloxypropane sulfonic acid. Examples of the phosphonic acids include nitrilo trimethylene phosphonic acid, hydroxyethylidene diphosphonic acid, ethylenediamine tetramethylene phosphonic acid, and phosphonobutane tricarboxylic acid. Examples of the polyphosphates include sodium tripolyphosphate and sodium hexametaphosphate.

[0041] As described above, it has been found that the water treatment method for the auxiliary cooling device of the air-cooled condenser of the present invention can secure a place for replenishing the water treatment agent in the circulation path, and can maintain a constant concentration of the water treatment agent in the circulating water. It has also been found that no measuring device or flow meter is required. [Explanation of symbols]

[0042] 1. Refrigeration unit 11 Cooling fan 2 Condenser 4 Auxiliary cooling device 41 Water-retaining material 42 Storage Tank 43 Water supply means 431 Supply Tank 432 Supply Pump 433 Ball Tap 44 Water treatment agent supply means 441 Water Treatment Agent Tank 442 Transport Pump 45 Circulation means 46 Circulating water discharge means 47 Circulation Route 471 Supply pipeline 472 Watering Section 473 Pit 474 Receiving Pipe

Claims

1. A water-retaining material is provided on the windward side of the air-cooled condenser, and circulating water containing a water treatment agent and water is circulated and supplied to the condenser, and the water-retaining material lowers the temperature of the air taken into the condenser by the latent heat generated when the circulating water is vaporized; A storage tank for storing the circulating water; A circulation means for circulating the circulating water between the water retention material and the storage tank; a circulating water discharge means for discharging a portion of the circulating water outside the circulation path when the circulation of the circulating water is stopped; A water supply means for supplying the water in the circulating water; A water treatment agent supplying means for supplying the water treatment agent in the circulating water; A water treatment method for an auxiliary cooling device of an air-cooled condenser, comprising: The water treatment method comprises: A water treatment method for an auxiliary cooling device of an air-cooled condenser, in which the replenishment of the water treatment agent by the water treatment agent replenishment means is performed after a portion of the circulating water is discharged outside the circulation path by the circulating water discharge means, and simultaneously with the replenishment of the water by the water replenishment means.

2. The water treatment method for an auxiliary cooling device of an air-cooled condenser according to claim 1 , wherein the water treatment agent is replenished in the storage tank.

3. 3. The water treatment method for an auxiliary cooling device of an air-cooled condenser according to claim 1, wherein the water treatment agent replenishment means replenishes the water treatment agent in an amount calculated from the amount of the circulating water discharged by the circulating water discharge means.

4. 3. The water treatment method for an auxiliary cooling device of an air-cooled condenser according to claim 1, wherein a supply position of the water treating agent by the water treating agent supply means is provided downstream of a supply position of the water by the water supply means.

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