JP2013015259A - Water treatment system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water treatment system that properly supplies a chemical in accordance with an operation state of the system.SOLUTION: The water treatment system includes: a cooling tower 110; a circulating water line L110; a makeup water line L120; an anticorrosive supplier 135 for supplying an anticorrosive to circulating water W110 and/or makeup water 121; a scale inhibitor supplier 134 for supplying a scale inhibitor to the circulating water W110 and/or the makeup water 121; an electrical conductivity detector 133; and a water quality controller for (i) supplying the anticorrosive from the anticorrosive supplier 135 when the electrical conductivity detected by the electrical conductivity detector 133 is lower than a first electrical conductivity ECth1, and (ii) supplying the scale inhibitor from the scale inhibitor supplier 134 when the electrical conductivity detected by the electrical conductivity detector 133 exceeds a second electrical conductivity ECth2.

Description

  The present invention relates to a water treatment system that circulates circulating water between a cooling tower and a device to be cooled.

  In commercial buildings, industrial plants, etc., cooling water is used to cool a device to be cooled (cooling load device) such as a heat exchanger incorporated in an air conditioner or a refrigerator. From the viewpoint of saving the cooling water, the cooling water is circulated and used while being cooled in the cooling tower (hereinafter, the circulating cooling water is appropriately referred to as “circulated water”). In a water treatment system, circulating water circulates between a cooling tower and a to-be-cooled device via a circulating water line (a circulating water supply line and a circulating water recovery line).

  A part of the circulating water evaporates when it is cooled by the cooling tower. For this reason, if circulating water is circulated continuously, the concentration of circulating water will become high gradually and water quality will deteriorate. Therefore, in order to improve the quality of circulating water, water (make-up water) is regularly replenished from the outside and part of the highly concentrated circulating water is discharged outside to dilute the circulating water. The process is running.

  In addition, in order to improve the quality of circulating water, chemicals are supplied to the circulating water (commonly called “medicine”). As a method for supplying medicine to the circulating water, a timer medicine injection system that repeats supply and stoppage of medicine alternately every predetermined time is known. Also known is a flow rate proportional chemical injection method for supplying a drug proportional to the amount of makeup water supplied (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 11-63746

  In the timer drug injection method described above, it is necessary to supply an excessive amount of drug in order to ensure a drug concentration of a certain level or more. Therefore, the user's economic burden increases. Further, the flow rate proportional chemical injection method can suppress excessive supply of the drug compared to the timer chemical injection method. However, in the flow proportional chemical injection method, the concentration of the drug tends to be low when the concentration of circulating water is low. For this reason, when the concentration of circulating water is low, for example, when an anticorrosive agent is supplied as a chemical, the concentration is lower than the original target concentration, so that the piping system is easily corroded.

Thus, in the conventional water treatment system, since the chemical | medical agent according to the driving | running condition of a system is not made, there existed a subject that troubles, such as corrosion, are easy to raise | generate a piping system.
Therefore, an object of this invention is to provide the water treatment system which can supply a chemical | medical agent appropriately according to the driving | running state of a system.

  The present invention provides a cooling tower for cooling the circulating water supplied to the apparatus to be cooled, a circulating water line for circulating the circulating water between the cooling tower and the apparatus to be cooled, and supplying makeup water to the cooling tower. A replenishing water line, an anticorrosive agent supplying means for supplying an anticorrosive agent to the circulating water and / or make-up water, a scale inhibitor supplying means for supplying the scale inhibitor to the circulating water and / or make-up water, and the electricity of the circulating water Electric conductivity detecting means for detecting conductivity; and (i) a first electric conductivity that is a lower limit threshold of electric conductivity at which the electric conductivity detected by the electric conductivity detecting means starts supplying the anticorrosive agent. If it is lower, the anticorrosive agent is supplied from the anticorrosive agent supply means, and (ii) the electric conductivity detected by the electric conductivity detector means the electric conductivity for starting the supply of the scale inhibitor. Second electrical conductivity that is the upper threshold If above, the water quality control means for executing processing to provide the scale inhibitor from the scale preventive agent supply means, to a water treatment system comprising a.

  The water treatment system further includes a sterilizing agent supplying means for supplying a sterilizing agent to the circulating water and / or makeup water, and the water quality control means is based on the electric conductivity detected by the electric conductivity detecting means. It is preferable to control the amount of the sterilizing agent supplied from the sterilizing agent supplying means.

  In the water treatment system, blow process execution means for discharging at least a part of the circulating water from the cooling tower and / or the circulating water line and executing a blow process for supplying make-up water into the cooling tower is provided. Further, the water quality control means, when the electrical conductivity detected by the electrical conductivity detection means exceeds a third electrical conductivity that is an upper limit threshold of electrical conductivity for starting execution of the blow process, It is preferable that the blow process is executed by the blow process execution means and the supply of the scale inhibitor from the scale inhibitor supply means is stopped.

  ADVANTAGE OF THE INVENTION According to this invention, the water treatment system which can supply a chemical | medical agent appropriately according to the driving | running state of a system can be provided.

It is a schematic structure figure showing water treatment system 100 of an embodiment. It is a functional block diagram concerning control of water treatment system 100 of an embodiment. It is a flowchart which shows the process sequence in case the chemical | medical agent supply control part 162 performs a blow process and a chemical | medical agent supply process.

  Hereinafter, a schematic configuration of a water treatment system 100 according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a water treatment system 100 of the present embodiment.

  As shown in FIG. 1, the water treatment system 100 of this embodiment circulates circulating water W110 (cooling water) in order to cool a cooled device 131 such as a heat exchanger incorporated in an air conditioner or a refrigerator. It is a system to let you. The circulating water W110 is circulated and used while being cooled by the cooling tower 110 from the viewpoint of saving. The cooling tower 110 in this embodiment is a so-called open type cooling tower.

  The water treatment system 100 of the present embodiment includes, as main components, a cooling tower 110, an apparatus to be cooled 131, an electrical conductivity measuring device 133 as an electrical conductivity detection unit, and scale prevention as a scale inhibitor supply unit. The agent supply apparatus 134, the anticorrosive agent supply apparatus 135 as an anticorrosive agent supply means, the bactericidal agent supply apparatus 136 as a bactericide supply means, and the system control apparatus 101 are provided. The water treatment system 100 includes a circulating water line L110 and a makeup water line L120 as main lines. The “line” is a general term for a line capable of fluid flow such as a flow path, a path, and a pipeline. Moreover, in FIG. 1, the path | route of electrical connection is shown with the broken line.

  The cooling tower 110 is a facility for cooling the circulating water W110 for cooling the apparatus to be cooled 131. The cooling tower 110 includes a tower main body 111, a water sprinkling unit 112, a storage unit 116, a louver 118, a fan 120, an upper opening 121, and a fan driving unit 122.

  The tower main body 111 is a housing that forms an outer shell of the cooling tower 110. A plurality of sprinklers 112, a fan 120, an upper opening 121, and a fan drive unit 122 are provided on the top of the tower body 111. A storage part 116 is provided in the lower part of the tower body 111. A louver 118 is provided on the side of the tower body 111.

  The water sprinkling unit 112 is a part that sprays the circulating water W110 in order to cool the circulating water W110 that cools the apparatus to be cooled 131. The sprinkling unit 112 sprays (sprinkles) the circulating water W110 recovered from the cooled device 131 through the circulating water recovery line L112 (described later) into the tower main body 111.

  The watering part 112 includes an upper water tank 113 and a watering port 114. A circulating water recovery line L112 (circulating water line L110) is connected to the upper water tank 113. The upper water tank 113 stores the circulating water W110 recovered from the cooled device 131 via the circulating water recovery line L112. The water spout 114 is composed of a nozzle formed on the lower side of the upper water tank 113 in order to spray the circulating water W110 stored in the upper water tank 113.

  The storage part 116 is a site | part which stores the circulating water W110 sprayed from the water sprinkling part 112. FIG. The storage part 116 is provided in the lower part of the tower main body 111. The circulating water W110 sprayed downward from the sprinkler 112 is cooled by exchanging heat with the outside air E1 (described later) having a low temperature in the process of falling inside the tower body 111. A circulating water supply line L111 (described later) of the circulating water line L110 is connected to the bottom of the storage unit 116. The circulating water W110 stored in the storage unit 116 is supplied to the cooled apparatus 131 via the circulating water supply line L111.

  The louver 118 is a vent hole for introducing outside air (air) E1 into the tower main body 111. Outside air E1 outside the tower body 111 is introduced into the tower body 111 via the louver 118.

  The upper opening 121 is an opening formed in the upper part of the tower main body 111. The upper opening 121 discharges the outside air E <b> 1 located inside the tower main body 111 to the outside of the tower main body 111. The air discharged from the upper opening 121 is also referred to as “exhaust E2”.

  The fan 120 is disposed in the upper opening 121. The fan 120 is connected to a rotation shaft (reference number omitted) of the fan driving unit 122. The fan 120 generates a negative pressure inside by rotating, and introduces the outside air E1 from the louver 118 to the inside of the tower main body 111, and the outside air E1 introduced into the inside of the tower main body 111 through the upper opening 121. To the outside of the tower body 111.

  The fan drive unit 122 is a drive source that rotates the fan 120. The fan drive unit 122 is configured by a motor (not shown). The fan drive unit 122 is disposed above the fan 120. The fan driving unit 122 is electrically connected to the system control device 101. Operation (drive and stop) of the fan drive unit 122, adjustment of the rotation speed (shift), and the like are controlled by a drive signal from the system control device 101.

  The circulating water line L110 is a line for circulating the circulating water W110 between the cooling tower 110 and the apparatus to be cooled 131. The circulating water line L110 includes a circulating water supply line L111 that supplies the circulating water W110 stored in the storage unit 116 from the cooling tower 110 to the cooled device 131, and a sprinkling unit of the cooling tower 110 that supplies the circulating water W110 from the cooled device 131. And a circulating water recovery line L112 for recovery to 112.

  The circulating water supply line L111 is a line that connects between the storage unit 116 of the cooling tower 110 and the apparatus to be cooled 131. The circulating water supply line L111 can supply the circulating water W110 stored in the storage unit 116 to the cooled device 131.

  A circulating water pump 132 is connected in the middle of the circulating water supply line L111. The circulating water pump 132 can send out the circulating water W110 from the upstream side to the downstream side of the circulating water line L110 (the circulating water supply line L111, the circulating water recovery line L112). The circulating water pump 132 is electrically connected to the system controller 101. The operation (drive and stop) of the circulating water pump 132 is controlled by a drive signal from the system controller 101.

  An upstream end portion of the measurement line L113 is connected to the connection portion J112 of the circulating water supply line L111.

  The circulating water recovery line L112 is a line that connects between the cooled device 131 and the sprinkler 112 of the cooling tower 110. The circulating water recovery line L <b> 112 can recover the circulating water W <b> 110 heated by heat exchange in the apparatus to be cooled 131 to the sprinkler 112 of the cooling tower 110. The downstream side of the circulating water recovery line L112 is branched into a plurality of lines at the branch portion J111. The branched line is connected to each of the plurality of sprinklers 112.

  The apparatus to be cooled 131 is various devices such as a heat exchanger that needs to be cooled by the circulating water W110. The apparatus to be cooled 131 is, for example, a turbo chiller or an absorption chiller for various chemical plants, an air conditioner chiller for buildings, a cold water production machine or a vacuum chiller for food factories, and the like. The apparatus to be cooled 131 includes a circulating water flow path (not shown) inside.

  In the cooled device 131, the downstream end of the circulating water supply line L111 is connected to one end of the circulating water flow path. In the cooled device 131, the upstream end of the circulating water recovery line L112 is connected to the other end of the circulating water flow path. Therefore, the circulating water flow path, together with the circulating water supply line L111 and the circulating water recovery line L112, forms a circulation path for circulating the circulating water W110 between the tower body 111 of the cooling tower 110 and the cooled device 131.

  The electrical conductivity measuring device 133 is a device that measures the electrical conductivity of the circulating water W110. The electrical conductivity measuring device 133 is connected to the circulating water line L110 at the connection portion J112 via the measurement line L113. In addition, the electrical conductivity measuring device 133 is electrically connected to the system control device 101. The electrical conductivity measured by the electrical conductivity measuring device 133 is transmitted to the system control device 101 as a detection signal. The electrical conductivity measuring device 133 measures the electrical conductivity at a predetermined time interval (or real time) and transmits it to the system control device 101.

  The scale inhibitor supply device 134 is a device that supplies the scale inhibitor to the storage unit 116 of the cooling tower 110. The scale inhibitor supply device 134 is connected to the storage unit 116 of the cooling tower 110 via a scale inhibitor supply line L131. The scale inhibitor is a chemical used to prevent scale growth in water or scale deposition on a pipe surface or the like. Examples of the scale inhibitor usable here include carboxylic acid polymers, acrylic acid polymers, phosphonic acid chelating agents, carboxylic acid chelating agents, and the like.

  The scale inhibitor supply device 134 is electrically connected to the system control device 101. The timing and supply amount of the scale inhibitor supplied from the scale inhibitor supply apparatus 134 to the storage unit 116 of the cooling tower 110 are controlled by a drive signal transmitted from the system control apparatus 101.

  The anticorrosive supply device 135 is a device that supplies the anticorrosive to the storage unit 116 of the cooling tower 110. The anticorrosive agent supply device 135 is connected to the storage unit 116 of the cooling tower 110 via an anticorrosive agent supply line L132.

  The anticorrosive is a chemical used mainly for suppressing the occurrence of overall corrosion in the piping system or the like, or partial corrosion such as pitting. Examples of the anticorrosive agent that can be used here include silicate, nitrite, zinc salt, molybdenum salt, phosphonocarboxylate, and benzotriazole derivative.

  The anticorrosive agent supply device 135 is electrically connected to the system control device 101. The timing and supply amount of the anticorrosive agent supplied from the anticorrosive agent supply device 135 to the storage unit 116 of the cooling tower 110 are controlled by a drive signal transmitted from the system control device 101.

  The sterilizing agent supply device 136 is a device that supplies the sterilizing agent to the storage unit 116 of the cooling tower 110. The sterilizing agent supply device 136 is connected to the storage unit 116 of the cooling tower 110 via the sterilizing agent supply line L133.

  In FIG. 1, the disinfectant supply device 136 is depicted as being connected to the bottom of the storage unit 116 of the cooling tower 110. However, the disinfectant supply device 136 is connected to the side wall or the like in the storage unit 116 of the cooling tower 110, similarly to the scale inhibitor supply device 134 and the anticorrosive agent supply device 135.

  A disinfectant is a chemical used to suppress the growth of microorganisms in water, and is also called a slime control agent. Examples of the bactericides that can be used here include halogen-based oxidizing agents such as sodium hypochlorite, oxygen-based oxidizing agents such as hydrogen peroxide, isothiazoline-based compounds, carbamate-based compounds, and the like.

  The disinfectant supply device 136 is electrically connected to the system control device 101. The timing and supply amount for supplying the sterilizing agent from the sterilizing agent supply device 136 to the storage unit 116 of the cooling tower 110 are controlled by a drive signal transmitted from the system control device 101.

  The cooling tower 110 is connected to a makeup water line L120. The makeup water line L120 is a line for replenishing the makeup water W121 to the storage section 116 of the cooling tower 110. The upstream side of the makeup water line L120 is a first makeup water line L121 connected to a supply source (not shown) of raw water W120 such as tap water or industrial water. On the other hand, the downstream side of the makeup water line L120 branches to the second makeup water line L122 and the third makeup water line L123 at the connecting portion J121. In the first makeup water line L121, a raw water pump 141 and a raw water valve 142 are provided in order from the upstream side.

  The raw water pump 141 can send makeup water W121 from the upstream side to the downstream side of the makeup water line L120. The raw water pump 141 is electrically connected to the system control device 101. The operation (drive and stop) of the raw water pump 141 is controlled by a drive signal from the system controller 101.

  The raw water valve 142 can open and close the makeup water line L120 on the discharge side of the raw water pump 141. The raw water valve 142 is electrically connected to the system controller 101 (connection path is not shown). The opening and closing of the valve body in the raw water valve 142 is controlled by a drive signal from the system control device 101.

  The downstream end of the second makeup water line L122 is connected to the tower body 111 of the cooling tower 110. A makeup water valve 143 is provided in the middle of the second makeup water line L122. The makeup water valve 143 is a water supply facility that forcibly supplies the makeup water W121 to the storage section 116 by opening and closing the second makeup water line L122. The makeup water valve 143 is electrically connected to the system control device 101. The opening and closing of the valve body in the makeup water valve 143 is controlled by a drive signal from the system control device 101.

  The downstream end of the third makeup water line L123 is connected to the tower main body 111 of the cooling tower 110. A water faucet 145 is provided at the downstream end of the third makeup water line L123. The water tap 145 is a ball tap type water supply facility that manages the water level (that is, the amount of water) of the circulating water W <b> 110 stored in the storage unit 116. When the water level of the circulating water W110 stored in the storage unit 116 decreases in the water tap 144, the ball tap operates and the supply water W121 flowing through the third supply water line L123 is supplied to the storage unit 116.

  The drain line L130 is connected to the bottom of the storage part 116 and extends downward. The drainage line L130 is a line that forcibly discharges the circulating water W110 stored in the storage unit 116 of the cooling tower 110 to the outside of the water treatment system 100 in a blow process described later. A drain valve 146 is provided in the middle of the drain line L130. The drain valve 146 can open and close the drain line L130. The drain valve 146 is electrically connected to the system control device 101. The opening and closing of the valve body in the drain valve 146 is controlled by a drive signal from the system control device 101.

  The cooling tower 110 is connected to an overflow line L140 in addition to the circulating water line L110, the makeup water line L120, and the drainage line L130 described above. The overflow line L140 discharges the circulating water W110 overflowing from the storage part 116 of the cooling tower 110 to the outside of the water treatment system 100 when the makeup water valve 143 is opened and the makeup water W121 is forcibly supplied. Line. That is, the overflow line L140 is configured to control the opening / closing control of the replenishing water valve 143 instead of the opening / closing control of the drain valve 146 in the blow process described later, thereby circulating water W110 stored in the storage unit 116 of the cooling tower 110, It functions as a line forcibly discharging out of the water treatment system 100.

  Next, with reference to FIG. 2, the function which concerns on control of the water treatment system 100 of this embodiment is demonstrated. FIG. 2 is a functional block diagram relating to control of the water treatment system 100 of the present embodiment.

  The system control apparatus 101 controls the operation of each unit in the water treatment system 100 of the present embodiment. As shown in FIG. 2, the system control apparatus 101 includes, for example, a fan drive unit 122, a circulating water pump 132, a raw water pump 141, a makeup water valve 143, a drain valve 146, a scale inhibitor supply device 134, and an anticorrosive agent supply device 135. And electrically connected to the disinfectant supply device 136.

  In addition, the system control device 101 is electrically connected to the measurement device of the water treatment system 100 and receives measurement information from this measurement device. For example, the system control device 101 is electrically connected to the electrical conductivity measuring device 133, and receives the electrical conductivity EC of the circulating water W110 measured by the electrical conductivity measuring device 133 as a detection signal.

  In the system controller 101, the electrical conductivity EC received from the electrical conductivity measuring device 133 is stored in the memory 103 (described later). Further, the electrical conductivity EC is sequentially updated to the latest value at a predetermined time interval (or real time).

  The system control apparatus 101 includes a control unit 102 and a memory 103. The control unit 102 includes a blow process execution unit 161 as a blow process execution unit and a chemical supply control unit 162 as a water quality control unit. The functions of the blow process execution unit 161 and the medicine supply control unit 162 in the control unit 102 are realized by a microprocessor (not shown) including a CPU and an internal memory.

  The blow process execution unit 161 simultaneously (or continuously) drains and replenishes the circulating water W110 as a blow process. The drainage of the circulating water W110 is performed by one of the following methods. Hereinafter, description will be made with reference to FIG.

(Forced drainage blow)
The blow process execution unit 161 opens the drain valve 146 to discharge a part of the circulating water W110 stored in the storage unit 116 of the cooling tower 110 from the drain line L130 to the outside. When a part of the circulating water W110 is discharged, the water level of the storage unit 116 is lowered, so that the ball tap of the water tap 145 is operated, and new makeup water W121 is replenished through the third makeup water line L123. When this forced drainage blow is performed, the replenishing water valve 143 remains in the closed state and no opening / closing operation is performed.

(Forced rehydration blow)
The blow process execution unit 161 opens the makeup water valve 143 and forcibly replenishes the storage section 116 with new makeup water W121 through the second makeup water line L122. When the makeup water W121 is replenished, the water level in the storage unit 116 rises, so that the overflowing circulating water W110 is discharged from the overflow line L140 to the outside. In addition, when this forced water replenishment blow is performed, the drain valve 146 remains in the closed state, and the opening / closing operation is not performed.

  The discharge of the circulating water W110 in the forced drainage blow is not limited to the storage unit 116 of the cooling tower 110, and may be discharged from a circulating water line L110 provided with a drain valve and a drain line (both not shown). Further, the circulating water W110 may be discharged from both the storage unit 116 of the cooling tower 110 and the circulating water line L110.

  As described above, when the makeup water W121 is replenished, the blow process execution unit 161 opens the makeup water valve 143 (in the case of forced supplemental water blow) or opens the drain valve 146 (in the case of forced drainage blow). ), Makeup water W121 is replenished from the makeup water line L120 to the storage section 116 of the cooling tower 110. Since the newly supplied makeup water W121 has a low electrical conductivity, the electrical conductivity of the circulating water W110 in the circulating water line L110 can be lowered as a whole.

The configuration of the control unit 102 shown in FIG. 2 will be described again.
The chemical supply control unit 162 controls the supply of the anticorrosive agent, the scale preventive agent, and the bactericidal agent based on the electrical conductivity EC of the circulating water W110 detected by the electrical conductivity measuring device 133, and the blow process execution unit 161. Controls the execution of the blow process.

  The medicine supply control unit 162 is configured such that the electrical conductivity EC of the circulating water W110 detected by the electrical conductivity measuring device 133 is less than the first electrical conductivity ECth1 that is the lower threshold value of the electrical conductivity for starting the supply of the anticorrosive. In this case, a process of supplying the anticorrosive agent from the anticorrosive agent supply device 135 is executed. The first electrical conductivity ECth1 is determined in consideration of the concentration of corrosive ions (such as chloride ions and sulfate ions) contained in the raw water W120, and is set to 40 mS / m, for example.

  Further, the medicine supply control unit 162 has a second electric conductivity ECth2 in which the electric conductivity EC of the circulating water W110 detected by the electric conductivity measuring device 133 is an upper limit threshold value of electric conductivity for starting the supply of the scale inhibitor. In the above case, the processing for supplying the scale inhibitor from the scale inhibitor supply apparatus 134 is executed. The second electrical conductivity ECth2 is determined in consideration of the concentration of scale-causing substances (silica, calcium ions, bicarbonate ions, carbonate ions, etc.) contained in the raw water W120, and is set to 50 mS / m, for example.

  The medicine supply control unit 162 cools the circulating water W110 detected by the electrical conductivity measuring device 133 when the electrical conductivity EC of the circulating water W110 is equal to or higher than the first electrical conductivity ECth1 and lower than the second electrical conductivity ECth2. The supply of the scale inhibitor and the anticorrosive agent to the storage part 116 of the tower 110 is stopped.

  In addition, when the electrical conductivity EC measured by the electrical conductivity measuring device 133 is equal to or higher than the third electrical conductivity ECth3, the medicine supply control unit 162 causes the blow process execution unit 161 to execute the blow process and the scale. The supply of the scale inhibitor from the inhibitor supply device 134 is stopped. The third electrical conductivity ECth3 is determined in consideration of the concentration factor that can ensure the sustainability of the effect of the scale inhibitor, and is set to 100 mS / m, for example.

  When the electrical conductivity EC measured by the electrical conductivity measuring device 133 is less than the fourth electrical conductivity ECth4, the medicine supply control unit 162 performs the first supply from the disinfectant supply device 136 to the storage unit 116 of the cooling tower 110. Supply a set amount of disinfectant.

  In addition, when the electrical conductivity EC measured by the electrical conductivity measuring device 133 is equal to or higher than the fourth electrical conductivity ECth4, the medicine supply control unit 162 stores the storage unit of the cooling tower 110 from the sterilizing agent supply device 136. 116 is supplied with a second set amount (> first set amount described later) of the bactericide.

  The fourth electrical conductivity ECth4 is determined in consideration of the sustainability of the effect of the first set amount of the bactericide, and is set to 80 mS / m, for example. The fourth electrical conductivity ECth4 is set to a value slightly lower than the third electrical conductivity ECth3 for executing the blow process. For this reason, during operation of the water treatment system 100 (except during the execution of the blow process), at least the first set amount of the bactericide is continuously supplied to the storage unit 116 of the cooling tower 110.

  In addition, 1st electrical conductivity ECth1, 2nd electrical conductivity ECth2, 3rd electrical conductivity ECth3, and 4th electrical conductivity ECth4 are set as the electrical conductivity of the circulating water W110 in the state containing a chemical | medical agent.

  Next, in the water treatment system 100 of the present embodiment, an operation when the medicine supply control unit 162 executes the blow process and the medicine supply process will be described with reference to FIG. FIG. 3 is a flowchart showing a processing procedure when the medicine supply control unit 162 executes a blow process and a medicine supply process. The control in the flowchart shown in FIG. 3 is executed by the control unit 102 based on a control program stored in the memory 103. 3 is repeatedly executed during operation of the water treatment system 100.

As shown in FIG. 3, in step ST <b> 101, the medicine supply control unit 162 transmits a drive signal to the sterilizing agent supply device 136 to supply the first set amount of sterilizing agent to the storage unit 116 of the cooling tower 110.
In step ST102, the medicine supply control unit 162 acquires the electrical conductivity EC of the circulating water W110 measured by the electrical conductivity measurement device 133.

  In step ST103, the medicine supply control unit 162 determines whether the acquired electrical conductivity EC is less than the first electrical conductivity ECth1. In this step ST103, when the drug supply control unit 162 determines that the electrical conductivity EC <the first electrical conductivity ECth1 (YES), it is a concentration that is likely to cause corrosion in the piping system or the like. The process moves to step ST104. In Step ST103, when the chemical supply control unit 162 determines that the electrical conductivity EC ≧ the first electrical conductivity ECth1 (NO), the concentration is not likely to cause corrosion in the piping system or the like. The process proceeds to step ST105.

  In step ST104 (step ST103: YES), the medicine supply control unit 162 transmits a drive signal to the anticorrosive agent supply device 135 to supply the anticorrosive agent to the storage unit 116 of the cooling tower 110. Thereafter, the process returns to step ST101 again.

  In step ST105, the medicine supply control unit 162 determines whether the acquired electrical conductivity EC is less than the second electrical conductivity ECth2. In this step ST105, when the drug supply control unit 162 determines that the electrical conductivity EC <the second electrical conductivity ECth2 (YES), the concentration is not likely to cause scale and corrosion. The process proceeds to step ST106. In step ST105, when the drug supply control unit 162 determines that the electrical conductivity EC ≧ the second electrical conductivity ECth2 (NO), the blow process is not necessary, but scale is likely to occur. Since it is the degree of enrichment, the process proceeds to step ST107.

  In step ST106 (step ST105: YES), the chemical supply control unit 162 transmits a stop signal to the anticorrosive agent supply device 135 to stop the supply of the anticorrosive agent to the storage unit 116 of the cooling tower 110. Thereafter, the process returns to step ST101 again.

  In step ST107 (step ST105: NO), the chemical supply control unit 162 transmits a drive signal to the scale inhibitor supply device 134 to supply the scale inhibitor to the storage unit 116 of the cooling tower 110.

  In Step ST108, the medicine supply control unit 162 determines whether the acquired electrical conductivity EC is less than the fourth electrical conductivity ECth4. In this step ST108, when the drug supply control unit 162 determines that the electrical conductivity EC <the fourth electrical conductivity ECth4 (YES), it is not the enrichment level at which microorganisms are likely to propagate, so the first set amount. In order to maintain the supply of the disinfectant, the process returns to step ST101 again. In Step ST108, when the drug supply control unit 162 determines that the electrical conductivity EC ≧ the fourth electrical conductivity ECth4 (NO), not only the scale is likely to be generated but also the microorganisms are easily propagated. Since it is the degree of concentration, the process proceeds to step ST109.

  In step ST109 (step ST108: NO), the medicine supply control unit 162 transmits a drive signal to the sterilizing agent supply device 136, and sets the second set amount (> first set amount) to the storage unit 116 of the cooling tower 110. Supply a disinfectant.

  In step ST110, the medicine supply control unit 162 determines whether or not the acquired electrical conductivity EC is less than the third electrical conductivity ECth3. In this step ST110, when the drug supply control unit 162 determines that the electrical conductivity EC <the third electrical conductivity ECth3 (YES), it is not the concentration that requires execution of the blow process. The process moves to step ST102 while maintaining the supply of the set amount of the bactericide. In Step ST110, if the drug supply control unit 162 determines that the electrical conductivity EC ≧ the third electrical conductivity ECth3 (NO), the concentration is a concentration that requires execution of the blow process. Moves to step ST111.

  In step ST <b> 111, the chemical supply control unit 162 transmits a stop signal to the scale inhibitor supply apparatus 134 to stop the supply of the scale inhibitor to the storage unit 116 of the cooling tower 110.

  In step ST112, the medicine supply control unit 162 causes the blow process execution unit 161 to execute a blow process. When the blow process execution unit 161 executes the blow process, part of the circulating water W110 stored in the storage unit 116 of the cooling tower 110 is discharged from the drain line L130 to the outside. Further, makeup water W121 is replenished from the makeup water line L120 to the storage section 116 of the cooling tower 110. After executing the blow process, the process returns to step ST101 again.

  Note that the blow process is controlled so as to end when a predetermined time or a predetermined amount of circulating water W110 is discharged. Alternatively, in the blow process, the electrical conductivity EC of the circulating water W110 is equal to or lower than a predetermined value lower than the third electrical conductivity ECth3 (for example, an intermediate value between the electrical conductivity of the raw water W120 and the first electrical conductivity ECth1). It can also be controlled to end when it becomes.

  According to the water treatment system 100 of this embodiment mentioned above, there exist the following effects, for example.

  When the electrical conductivity EC of the circulating water W110 is less than the first electrical conductivity ECth1, the water treatment system 100 of the present embodiment supplies an anticorrosive agent from the anticorrosive agent supply device 135, and the electrical conductivity of the circulating water W110. When the EC is equal to or higher than the second electrical conductivity ECth2, the medicine supply control unit 162 that supplies the scale inhibitor from the scale inhibitor supply apparatus 134 is provided.

  Therefore, when the degree of concentration of the circulating water W110 is low, the anticorrosive agent is supplied to the circulating water W110, so that corrosion of the piping system can be suppressed. Further, when the concentration of the circulating water W110 is low, the hardness of the circulating water W110 is not increased and the water quality is unlikely to generate scale. Therefore, no scale inhibitor is supplied to the circulating water W110. For this reason, the excessive supply of a scale inhibitor can be suppressed.

On the other hand, when the degree of concentration of the circulating water W110 is high, the scale inhibitor is supplied to the circulating water W110, so that generation of scale in the piping system can be suppressed. In addition, when the concentration of the circulating water W110 is high, the hardness of the circulating water W110 is increased, and the water quality is such that corrosion does not easily occur. Therefore, the anticorrosive agent is not supplied to the circulating water W110. For this reason, excessive supply of the anticorrosive agent can be suppressed.
Therefore, according to the water treatment system 100 of the present embodiment, the medicine can be appropriately supplied according to the operation status of the system.

  In the water treatment system 100 of the present embodiment, the chemical supply control unit 162 continuously supplies at least the first set amount of the bactericide, and the electrical conductivity EC of the circulating water W110 is the fourth electrical conductivity ECth4. When it becomes above, the 2nd set amount (> 1st set amount) disinfectant is supplied.

  According to this, even when the concentration of the circulating water W110 is low, since at least the first set amount of the bactericidal agent is supplied, the minimum concentration of the bactericide necessary for suppressing the growth of microorganisms in the circulating water system. Can be maintained. In particular, when the path of the circulating water line L110 is long or when the volume of the reservoir 116 is large, it takes time until the effect of the bactericide by the second set amount is reflected. For this reason, it is possible to effectively suppress the growth of microorganisms in the circulating water system by continuously supplying the first set amount of the bactericide. Further, when the concentration of the circulating water W110 becomes high, the second set amount of the bactericide increased from the first set amount is supplied, so that sterilization sufficient to suppress the growth of microorganisms in the circulating water system. The concentration of the agent can be ensured.

  In the water treatment system 100 of the present embodiment, the chemical supply control unit 162 causes the blow process to be executed when the electrical conductivity EC of the circulating water W110 is equal to or higher than the third electrical conductivity ECth3, and the scale inhibitor Stop supplying.

  Therefore, when the concentration of the circulating water W110 becomes low due to the execution of the blow process, the scale inhibitor is not supplied. For this reason, the excessive supply of a scale inhibitor can be suppressed.

  As mentioned above, although preferred embodiment of this invention was described, this invention can be implemented with a various form, without being limited to embodiment mentioned above.

  In the present embodiment, at least the first set amount of the bactericide is continuously supplied until the electrical conductivity EC of the circulating water W110 becomes equal to or higher than the fourth electrical conductivity ECth4. Not limited to this, when the electrical conductivity EC of the circulating water W110 is less than the fourth electrical conductivity ECth4, no bactericidal agent is supplied, and the electrical conductivity EC of the circulating water W110 becomes equal to or higher than the fourth electrical conductivity ECth4. For example, the second set amount of the bactericidal agent may be supplied only when the sterilizing agent is used.

  In the present embodiment, when the electrical conductivity EC of the circulating water W110 becomes equal to or higher than the fourth electrical conductivity ECth4, the second set amount (fixed value) of the bactericide is supplied. Not limited to this, when the electrical conductivity EC of the circulating water W110 becomes equal to or higher than the fourth electrical conductivity ECth4, the supply amount of the bactericide may be increased in proportion to the increase amount. By performing such control, the sterilizing effect can be enhanced according to the concentration of the circulating water W110.

  In this embodiment, the example which supplies the scale inhibitor, the anticorrosive, and the disinfectant as a chemical | medical agent to the circulating water W110 was demonstrated. Not limited to this, these chemicals may be supplied to the makeup water W121. Alternatively, these chemicals may be supplied to both the circulating water W110 and the makeup water W121.

  In this embodiment, the example which supplies the scale inhibitor, the anticorrosive, and the disinfectant as a chemical | medical agent to the storage part 116 of the cooling tower 110 was demonstrated. Not only this but these chemical | medical agents may be supplied to the watering part 112 or the circulating water line L110 (the circulating water supply line L111, the circulating water collection | recovery line L112) of the cooling tower 110. FIG.

  In this embodiment, although the example which comprised the cooling tower 110 as an open type cooling tower was shown, it does not restrict to this and you may comprise the cooling tower 110 as a closed type cooling tower.

DESCRIPTION OF SYMBOLS 100 Water treatment system 101 System control apparatus 102 Control part 103 Memory 110 Cooling tower 112 Sprinkling part 116 Storage part 131 Cooled apparatus 133 Electrical conductivity measuring apparatus (electrical conductivity detection means)
134 Scale inhibitor supply device (scale inhibitor supply means)
135 Anticorrosive supply device (corrosion preventive supply means)
136 Disinfectant supply device (disinfectant supply means)
161 Blow process execution unit (Blow process execution means)
162 Drug supply control unit (water quality control means)
L110 Circulating water line L120 Makeup water line L140 Drainage line W110 Circulating water W120 Makeup water

Claims (3)

A cooling tower for cooling the circulating water supplied to the apparatus to be cooled;
A circulating water line for circulating circulating water between the cooling tower and the cooled device;
A makeup water line for supplying makeup water into the cooling tower;
An anticorrosive supply means for supplying an anticorrosive to the circulating water and / or makeup water;
Anti-scale agent supply means for supplying anti-scale agent to circulating water and / or makeup water;
Electrical conductivity detecting means for detecting the electrical conductivity of the circulating water;
(I) When the electrical conductivity detected by the electrical conductivity detecting means is lower than the first electrical conductivity which is a lower threshold of electrical conductivity for starting the supply of the anticorrosive agent, the anticorrosive agent supplying means (Ii) When the electrical conductivity detected by the electrical conductivity detecting means exceeds the second electrical conductivity that is the upper limit threshold value of electrical conductivity for starting the supply of the scale inhibitor. The water quality control means for executing the process of supplying the scale inhibitor from the scale inhibitor supply means,
A water treatment system comprising. A sterilizing agent supplying means for supplying the sterilizing water to the circulating water and / or makeup water;
2. The water treatment system according to claim 1, wherein the water quality control unit controls the amount of the sterilizing agent supplied from the sterilizing agent supplying unit based on the electrical conductivity detected by the electrical conductivity detecting unit. And further comprising a blow process execution means for discharging a at least part of the circulating water from the cooling tower and / or the circulating water line and executing a blow process for supplying make-up water into the cooling tower,
The water quality control means executes the blow process when the electric conductivity detected by the electric conductivity detection means exceeds a third electric conductivity that is an upper limit threshold of electric conductivity for starting execution of the blow process. The water treatment system according to claim 1 or 2, wherein the blow process is executed by the means and the supply of the scale inhibitor from the scale inhibitor supply means is stopped.

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