JP2018176065A - Cooling water system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling water system capable of suppressing generation of scale in piping and corrosion of the piping.SOLUTION: A cooling water system comprises a circulation unit, a first replenishment unit, and a second replenishment unit. The circulation unit circulates cooling water. The first replenishment unit replenishes the cooling water with a first replenishment water containing rainwater. The second replenishment unit replenishes the cooling water with a second replenishment water containing one or more selected from the group consisting of clean water, groundwater, river water, lake water, reservoir water, and spring water. The cooling water system, for example, further comprises a scale component supplement unit which supplements one or more selected from the group consisting of the cooling water, the first replenishment water, and the second replenishment water with a scale component.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to cooling water systems.

  Conventionally, a cooling water system for circulating cooling water is known (see Patent Document 1). Fresh water etc. is used as cooling water.

Patent No. 3172727

  Top water contains scale components. There is a problem that when a portion of the water evaporates in the process of using the tap water as the cooling water and the scale components are concentrated, the scale is easily generated in the piping. It is conceivable to use rainwater as cooling water. The use of rainwater as cooling water is likely to corrode piping because the scale component contained in rainwater is excessively small.

  One aspect of the present disclosure is to provide a cooling water system capable of suppressing scale formation and corrosion of piping in piping.

  One aspect of the present disclosure includes a circulation unit that circulates cooling water, a first replenishment unit that supplements the first replenishment water containing rainwater to the cooling water, fresh water, underground water, river water, lake water, water of a pond, And a second replenishment unit for replenishing the cooling water with a second makeup water including one or more selected from the group consisting of: and spring water.

  The cooling water system which is one aspect of the present disclosure can replenish both the first makeup water including rainwater and the second makeup water to the cooling water. Therefore, compared with the case where only the second makeup water is supplied to the cooling water, the generation of the scale in the pipe can be suppressed. This is because the amount of the scale component contained in the first makeup water is smaller than that in the second makeup water.

  Moreover, the cooling water system which is one aspect of this indication can control corrosion of piping compared with a case where only the 1st makeup water is supplied to cooling water. This is because the amount of the scale component contained in the second makeup water is larger than that of the first makeup water.

FIG. 2 is an explanatory view illustrating an entire configuration of a cooling water system 1; FIG. 2 is a block diagram showing an electrical configuration of a cooling water system 1; It is a flowchart showing the process which the control part 67 performs. It is explanatory drawing showing the whole structure of the cooling water system 1 of another form.

Embodiments of the present disclosure will be described based on the drawings.
First Embodiment
1. Overall Configuration of Cooling Water System 1 The overall configuration of the cooling water system 1 will be described based on FIG. As shown in FIG. 1, the cooling water system 1 includes a cooling water tank 3, a pipe 5, a pump 7, a pipe 9, a pump 11, a float switch 13, and a water temperature gauge 15.

  The cooling water tank 3 holds the cooling water. The capacity of the cooling water tank 3 is 6000 L, for example. The pipe 5 is drawn from the cooling water tank 3, passes through the inside of the resin molding machine 17, and returns to the cooling water tank 3. The pump 7 is provided in the middle of the pipe 5. The cooling water in the cooling water tank 3 flows in the piping 5 by the driving force of the pump 7 and returns to the cooling water tank 3. That is, the cooling water circulates through a system consisting of the cooling water tank 3 and the pipe 5. The cooling water flowing in the piping 5 cools the resin molding machine 17 when passing through the resin molding machine 17. The cooling water tank 3, the pipe 5, and the pump 7 correspond to a circulation unit.

  The pipe 9 is derived from the cooling water tank 3, passes through the ground, and returns to the cooling water tank 3. The pump 11 is provided in the middle of the pipe 9. The cooling water in the cooling water tank 3 flows in the pipe 9 by the driving force of the pump 11 and returns to the cooling water tank 3. The cooling water flowing in the pipe 9 dissipates heat when passing through the ground. The flow rate of the cooling water in the pipe 9 is, for example, 15 L / min.

  The float switch 13 detects the water level of the cooling water held in the cooling water tank 3 and outputs the detection result to the control unit 67 described later. The water temperature gauge 15 detects the temperature of the cooling water held in the cooling water tank 3 and outputs the detection result to the control unit 67.

  The cooling water system 1 further includes a first replenishment unit 19. The first replenishment unit 19 includes a rainwater receiver 21, a pipe 23, an initial rainwater drainage device 25, a pipe 27, a rainwater tank 29, a pipe 31, a solenoid valve 33, a manual valve 34, a float switch 35, and the like. And.

  The rainwater receptacle 21 receives rainwater falling from the roof 37 and sends it to the piping 23. The pipe 23 sends the rainwater to the initial rainwater drainage device 25. The initial rainwater drainage device 25 includes a first tank 39, a second tank 41, and a connection pipe 43. The connection pipe 43 is a pipe that connects the lower portion of the first tank 39 and the second tank 41. At the lower part of the second tank 41, a discharge pipe 45 for discharging rain water at a constant flow rate is provided. The pipe 23 supplies the first tank 39 with rainwater. The first tank 39 sends rainwater to the second tank 41 through the connection pipe 43. In addition, the first tank 39 sends the overflowed rainwater to the pipe 27 when the water level of the rainwater in the first tank 39 becomes equal to or higher than a predetermined height.

  The initial rainwater drainage device 25 works as follows. Since the water level of the rainwater in the first tank 39 is low in the early stage of rainfall, all the water supplied to the first tank 39 by the pipe 23 is sent to the second tank 41 through the connection pipe 43 and is supplied to the pipe 27 Can not be sent. After that, when the rainfall continues, the water level of the rainwater in the first tank 39 and the second tank 41 rises, and the water level of the rainwater in the first tank 39 becomes a predetermined height or more, the first tank 39 pipes the overflowed rainwater. Send to

  By the above-described operation, the initial rainwater drainage device 25 can drain the dirty water supplied from the piping 23 at the initial stage of rainfall, and send the less contaminated rain water supplied from the piping 23 to the piping 27 thereafter. .

  The piping 27 supplies rainwater to the rainwater tank 29. The rainwater tank 29 holds rainwater. The capacity of the rainwater tank 29 is, for example, 6000 L. The pipe 31 supplies the rainwater held in the rainwater tank 29 to the pipe 9. The flow rate of rainwater in the piping 31 is, for example, 0.5 to 1.0 L / min.

  The solenoid valve 33 opens and closes the pipe 31. The solenoid valve 33 is controlled by the controller 67. The manual valve 34 opens and closes the pipe 31. The manual valve 34 is operated by the user. The float switch 35 detects the level of rainwater held in the rainwater tank 29, and outputs the detection result to the control unit 67. Rainwater corresponds to the first makeup water.

  The cooling water system 1 further includes a second replenishment unit 47. The second supply unit 47 includes a pipe 49, an electromagnetic valve 51, and a manual valve 53. The pipe 49 supplies clean water to the cooling water tank 3. The flow rate of the clean water in the pipe 49 is, for example, 0.5 to 1.0 L / min. The pipe 49 is in parallel in the portion provided with the solenoid valve 51 and the manual valve 53. The solenoid valve 51 opens and closes the pipe 49. The solenoid valve 51 is controlled by the controller 67. The manual valve 53 opens and closes the pipe 49. The manual valve 53 is operated by the user. The clean water corresponds to the second make-up water.

  The cooling water system 1 further includes scale component supply units 55, 57. The scale component supply unit 55 supplies the scale component to the cooling water in the cooling water tank 3. The scale component supply unit 57 supplies the scale component to the rainwater in the rainwater tank 29. The scale component is a substance that causes scale in the piping. Examples of the scale component include calcium salt, silica and the like. As a calcium salt, calcium carbonate, calcium sulfate, calcium hydroxide etc. are mentioned, for example. The scale component supply units 55 and 57 are controlled by the controller 67.

  The cooling water system 1 further includes a scale component removing unit 59. The scale component removing unit 59 includes a removing device 61 and a pipe 63. The pipe 63 takes out the cooling water from the cooling water tank 3, passes the removing device 61, and returns the cooling water to the cooling water tank 3. The removing device 61 removes the scale component from the cooling water supplied by the pipe 63. Examples of the removing device 61 include a DB scale separator manufactured by Koganei Co., Ltd., and the like. This DB scale separator removes scale components such as calcium carbonate, ionic silica and the like by a dielectric breakdown electrolytic reaction using a titanium plate as an electrode. The titanium plate is a consumable item. The more scale components to be removed, the more exhaustion of the titanium plate.

  The cooling water system 1 further includes an index acquisition unit 65. The index acquisition unit 65 acquires an index (hereinafter referred to as a scale index) representing a scale formation tendency of the cooling water in the cooling water tank 3. As the scale index, for example, stability index, Langeria index, calcium concentration, silica concentration and the like can be mentioned. When the scale index is the stability index, examples of the index acquisition unit 65 include a stability index automatic measuring device described in JP-A-10-332679. When the scale index is the langelian index, examples of the index acquisition unit 65 include a measurement and calculation device described in Japanese Patent No. 3385767.

2. Electrical Configuration of Cooling Water System 1 The electrical configuration of the cooling water system 1 will be described based on FIG. The cooling water system 1 includes a control unit 67. The control unit 67 is mainly configured of a known microcomputer having a CPU 69 and a semiconductor memory (hereinafter, referred to as a memory 71) such as a RAM, a ROM, and a flash memory. The various functions of the control unit 67 are realized by the CPU 69 executing a program stored in a non-transitional tangible recording medium. In this example, the memory 71 corresponds to a non-transitional tangible storage medium storing a program. Also, by executing this program, a method corresponding to the program is executed. The number of microcomputers constituting the control unit 67 may be one or more.

  The control unit 67 is connected to the float switches 13 and 35, the water temperature gauge 15, the solenoid valves 33 and 51, the scale component supply units 55 and 57, the scale component removal unit 59, and the index acquisition unit 65 described above.

  The control unit 67 controls the solenoid valve 51 based on the detection results of the float switch 13 and the water temperature gauge 15. The aspect of the control is as follows. When the water temperature detected by the water temperature gauge 15 is 38 ° C. or more, the solenoid valve 51 is opened. When the water temperature detected by the water temperature gauge 15 is 35 ° C. or less, the solenoid valve 51 is closed. However, when the water level detected by the float switch 13 is below the predetermined lower limit water level, the solenoid valve 51 is opened regardless of the water temperature.

  The controller 67 controls the solenoid valve 33 based on the detection result of the float switch 35. The aspect of the control is as follows. When the water level detected by the float switch 35 is equal to or higher than a predetermined upper limit water level, the solenoid valve 33 is opened. When the water level detected by the float switch 35 is below the predetermined lower limit water level, the solenoid valve 33 is closed. The lower limit water level is lower than the upper limit water level.

  The control unit 67 controls the scale component supply units 55 and 57 and the scale component removal unit 59 based on the detection result of the index acquisition unit 65. The aspect of the control will be described later.

3. Scale Component Adjustment Process Performed by Control Unit 67 The scale component adjustment process performed by the control unit 67 will be described based on FIG. This process is performed at a predetermined cycle. The cycle is not particularly limited, and may be, for example, every other day, every other week, every other month, or the like.

In step 1, the scale acquisition unit 65 is used to acquire a scale index in cooling water.
In step 2, the scale index acquired and stored in the past is read out from the memory 71. The past scale index is stored when the process of step 7 described later is executed in the past.

  In step 3, the scale index obtained in step 1 and the scale index read out in step 2 have a smaller scale generation tendency than the preset first reference value continuously for one year or more (hereinafter referred to as Then, it is judged whether or not it is in the under area). If the scale index is in the undersized area continuously for one year or more, the process proceeds to step 4; otherwise, the process proceeds to step 5.

When the scale index is the stability index, the first reference value can be, for example, seven. In this case, an area exceeding 7 is an undersized area.
In step 4, the scale component is supplied to the cooling water in the cooling water tank 3 using the scale component supply unit 55, and the scale component is supplied to the rainwater in the rainwater tank 29 using the scale component supply unit 57. The supply amount of the scale component may be a fixed value, or may be a value calculated according to the scale index acquired in step 1 described above. For example, the larger the difference between the scale index acquired in step 1 and the first reference value, the larger the amount of supply of the scale component can be.

  In step 5, the scale index obtained in step 1 and the scale index read out in step 2 have a scale generation tendency larger than a preset second reference value continuously for one year or more (hereinafter referred to as Then, it is judged whether or not it is in the over area. If the scale index is in the oversized area continuously for one year or more, the process proceeds to step 6; otherwise, the process proceeds to step 7.

When the scale index is a stability index, the second reference value can be, for example, 6. In this case, an area of less than 6 is an excessive area.
In step 6, at least a portion of the scale component is removed from the cooling water in the cooling water tank 3 using the scale component removing unit 59. The removal amount of the scale component may be a fixed value, or may be a value calculated according to the scale index acquired in step 1 described above. For example, as the difference between the scale index acquired in step 1 and the second reference value is larger, the removal amount of the scale component can be increased.

  In step 7, the scale index acquired in step 1 is stored in the memory 71 in association with the time when the scale index is acquired. The scale index stored in this step is read out in step 2 when the process shown in FIG. 3 is performed again later.

4. Effects of Cooling Water System 1 (1A) The cooling water system 1 can replenish both the rainwater and the clean water to the cooling water. Therefore, it is possible to suppress the generation of scales in the pipes 5 and 9 and the cooling water tank 3 as compared to the case where only the fresh water is supplied to the cooling water. This is because the amount of scale components contained in the rainwater is smaller than that of the fresh water.

  Further, the cooling water system 1 can suppress the corrosion of the pipes 5 and 9 and the cooling water tank 3 as compared to the case where only rain water is supplied to the cooling water. This is because the amount of scale components contained in the tap water is larger than that of rainwater.

  (1B) The cooling water system 1 can supply the scale component to the cooling water in the cooling water tank 3 using the scale component supply unit 55. In addition, the cooling water system 1 can supply the scale component to the rainwater in the rainwater tank 29 using the scale component supply unit 57. Therefore, corrosion of the pipes 5 and 9 and the cooling water tank 3 can be further suppressed. Moreover, corrosion of the rainwater tank 29 and the piping 31 can also be suppressed.

  (1C) The cooling water system 1 further includes an index acquisition unit 65 that acquires a scale index of the cooling water. The scale component supply units 55 and 57 supply the scale component on condition that the scale index acquired by the index acquisition unit 65 is continuously in the undersized area for one year or more. Therefore, the scale index in the cooling water can be maintained in a suitable range in which corrosion and scale do not easily occur.

  (1D) The cooling water system 1 further includes a scale component removing unit 59 that removes at least a portion of the scale components from the cooling water. Therefore, the generation of the scale in the pipes 5 and 9 and the cooling water tank 3 can be further suppressed.

  (1E) The scale component removal unit 59 removes the scale component on the condition that the scale index acquired by the index acquisition unit 65 is continuously in the excessive area for one year or more. Therefore, the scale index in the cooling water can be maintained in a suitable range in which corrosion and scale do not easily occur.

(1F) Since the cooling water system 1 supplies rainwater to the cooling water, the scale component contained in the cooling water can be reduced compared to the case where only the clean water is replenished to the cooling water. Therefore, the operation time of the scale component removing unit 59 can be reduced. As a result, the frequency of replacement of consumables in the scale component removing unit 59 can be reduced.
Other Embodiments
As mentioned above, although embodiment of this indication was described, this indication can be variously deformed and implemented, without being limited to the above-mentioned embodiment.

  (1) As shown in FIG. 4, the cooling water system 1 may immerse the scale component-containing substance 73 in the cooling water in the cooling water tank 3 without including the scale component supply units 55 and 57. Examples of the scale component-containing substance 73 include oyster shells. Oyster shells contain calcium carbonate. From the scale component-containing substance 73, the scale component gradually elutes into the cooling water. By immersing the scale component-containing substance 73 in the cooling water in the cooling water tank 3, it is possible to suppress an excessive decrease in the scale component in the cooling water. As a result, corrosion of the pipes 5 and 9 and the cooling water tank 3 can be suppressed.

  The scale component-containing substance 73 may be immersed in rainwater in the rainwater tank 29. Alternatively, the scale component-containing substance 73 may be immersed in both the cooling water in the cooling water tank 3 and the rainwater in the rainwater tank 29.

(2) The cooling water system 1 may not include one or both of the scale component supply units 55 and 57.
(3) The cooling water system 1 may not include the scale component removing unit 59.

  (4) The cooling water system 1 may not include the index acquisition unit 65. In this case, for example, the user can decide when to use the scale component supply units 55 and 57. Alternatively, the scale component supply units 55 and 57 may be used according to a predetermined program.

  Moreover, when the cooling water system 1 is not equipped with the parameter | index acquisition unit 65, a user can decide the timing which uses the scale component removal unit 59, for example. Alternatively, the scale component removal unit 59 may be used according to a predetermined program.

(5) The scale component removing unit 59 may remove scale components from the upper water in the pipe 49.
(6) The rainwater tank 29 may be supplied with other water together with the rainwater. And the water which mixed rain water and other water may be supplied to piping 9.

(7) The second supply unit 47 may supply the cooling water tank 3 with water other than the clean water. Examples of water other than clean water include groundwater, river water, lake water, water of reservoirs, spring water and the like.
(8) The cooling water system 1 may cool the cooling water by a cooling tower. The cooling water system 1 can replenish rainwater to the cooling water by the amount of water evaporated in the cooling tower. This can suppress concentration of scale components in the cooling water. Moreover, since the scale component which a cooling water contains is not discharged | emitted, even if it replenishes a rainwater to a cooling water, the corrosiveness in a cooling water can be suppressed.

(9) The scale component supply units 55 and 57 may supply the scale component to the upper water in the pipe 49.
(10) The object to be cooled by the cooling water system 1 may be something other than the resin molding machine 17.

  (11) The cooling water system 1 may switch the state of the cooling water alternately between the first state and the second state in which the scale component is more than the first state. The first state is a state in which the corrosiveness is higher than the second state. The second state is a state in which the scale is more easily generated than the first state.

  By doing this, the following effects can be obtained. In the second state, an anticorrosive coating consisting of a scale component is formed in the pipe. In the following first state, corrosion of the pipe is suppressed by the anticorrosive coating. At the end of the first state, the anticorrosive coating is removed.

  The period per one time of the first state and the second state can be, for example, several weeks to several months. The cooling water system 1 can supply or remove scale components based on, for example, a scale index, and can control the state of the cooling water. Alternatively, the scale component can be supplied or removed at a preset timing to control the state of the cooling water.

  (12) The cooling water system 1 may supply at least a part of the scale component removed by the removal device 61 by the scale component supply units 55 and 57. By doing this, the amount of scale components to be newly prepared can be suppressed.

  In addition, a tank for storing the scale component removed by the removing device 61 or a liquid containing the same (hereinafter, referred to as a scale component storage tank) may be provided. Then, the scale component storage tank and the rainwater tank 29 may be connected by piping. The scale component can be supplied from the scale component storage tank to the rainwater tank 29 through piping. By doing this, the amount of scale components to be newly prepared can be suppressed. The above piping may be always open or may be opened and closed by a valve.

  In addition, in the second state described in the above (11), the scale component removed by the removing device 61 may be kept in the removing device 61. In the next first state, the retained scale component dissolves into the cooling water, and the corrosiveness of the cooling water is suppressed.

  (13) The same configuration as that of the cooling water system 1 can be applied to the existing cooling water circuit. In this case, even if a large amount of scale is attached to the existing cooling water circuit, the scale can be removed. That is, the effect of cleaning the scale can be exhibited.

  (14) The function of one component in each of the above embodiments may be shared by a plurality of components or the function of a plurality of components may be exhibited by one component. In addition, part of the configuration of each of the above embodiments may be omitted. In addition, at least a part of the configuration of each of the above-described embodiments may be added to or replaced with the configuration of the other above-described embodiments. In addition, all the aspects contained in the technical thought specified from the wording as described in a claim are an embodiment of this indication.

  (15) In addition to the cooling water system described above, a higher-order system having the cooling water system as a component, a program for causing a computer to function as the control unit 67, non-transitional actual conditions such as semiconductor memory recording this program The present disclosure can also be realized in various forms, such as physical recording media, cooling water management methods, and the like.

DESCRIPTION OF SYMBOLS 1 ... Cooling water system, 3 ... Cooling water tank, 5, 9, 23, 27, 31, 49, 63 ... Piping, 7, 11 ... Pump, 13, 35 ... Float switch, 15 ... Water thermometer, 17 ... Resin molding Machine 19 19st replenishment unit 21 rainwater receiver 25 initial rainwater drainage device 29 rainwater tank 33, 51 solenoid valve 34, 53 manual valve 37 roof 39 first tank 41 ... second tank, 43 ... connection pipe, 45 ... discharge pipe, 47 ... second replenishment unit, 55, 57 ... scale component supply unit, 59 ... scale component removal unit, 61 ... removal device, 65 ... index acquisition unit, 67: control unit, 69: CPU, 71: memory, 73: substance containing scale component

Claims (7)

A circulation unit for circulating cooling water;
A first replenishment unit for replenishing the cooling water with first makeup water containing rainwater;
A second replenishing unit replenishing the cooling water with a second replenishing water containing one or more selected from the group consisting of drinking water, groundwater, river water, lake water, pond water, and spring water;
Cooling water system comprising. The cooling water system according to claim 1, wherein
The cooling water system further comprising a scale component supply unit for supplying a scale component to one or more selected from the group consisting of the cooling water, the first makeup water, and the second makeup water. The cooling water system according to claim 2, wherein
The cooling water further includes an index acquisition unit that acquires an index indicating a scale generation tendency in the cooling water,
The cooling configured to supply the scale component on condition that the index acquired by the index acquisition unit is in a region where the scale generation tendency is smaller than a preset reference value, the scale component supply unit Water system. The cooling water system according to claim 1, wherein
The cooling water system further comprising a scale component removing unit that removes at least a portion of the scale component from the cooling water and / or the second makeup water. The cooling water system according to claim 4, wherein
The cooling water further includes an index acquisition unit that acquires an index indicating a scale generation tendency in the cooling water,
The cooling configured to remove the scale component on condition that the indicator acquired by the indicator acquiring unit is in a region where the scale generation tendency is larger than a preset reference value, the scale component removing unit Water system. The cooling water system according to claim 1, wherein
A scale component supply unit for supplying a scale component to one or more selected from the group consisting of the cooling water, the first makeup water, and the second makeup water;
A scale component removing unit that removes at least a portion of the scale component from the cooling water and / or the second makeup water;
The cooling water system further comprising. The cooling water system according to claim 6, wherein
The cooling water further includes an index acquisition unit that acquires an index indicating a scale generation tendency in the cooling water,
The scale component supply unit is configured to supply the scale component on condition that the index acquired by the index acquisition unit is in a region in which the scale generation tendency is smaller than a preset first reference value. ,
The scale component removal unit is configured to remove the scale component on the condition that the index acquired by the index acquisition unit is in a region where the scale generation tendency is larger than a second reference value set in advance. Cooling water system.

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