JP2015039654A - Ion exchange apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ion exchange apparatus capable of maintaining the bacterial count in a pressure tank at a level less than water quality standard for the tap water at all times.SOLUTION: An ion exchange apparatus 1 includes: a pressure tank in which an ion exchange resin floor is accommodated; flow channel switching means 3 capable of switching flow channels corresponding to respective modes including a water treatment mode, a regeneration mode, and a washing mode; flow rate measuring means 61; timing means 52 which initiates timing of the time period of passing no water when water passing to the pressure tank is halted; and a controlling unit 51 which switches the flow channel switching means 3 to the flow channel corresponding to the washing mode when the time period of passing no water reaches a pre-specified time. When the water passing to the pressure tank is resumed, the controlling unit 51 calculates the cumulative number of bacteria supposed to have been removed from the pressure tank based on the water passing duration, the instantaneous flow rate measured by the flow rate measuring means 61, and a removal coefficient corresponding to the instantaneous flow rate. When the cumulative number of bacteria reaches a pre-set target cumulative number, the time period of passing no water is reset.

Description

  The present invention relates to an ion exchange device such as a water softening device.

  In recent years, the characteristics and effectiveness of soft water have attracted attention as water for domestic use and processing water in the food manufacturing industry, and ion exchange devices for producing soft water (so-called soft water softening devices) have begun to spread. . An ion exchange device for producing soft water produces soft water, which is treated water, by adsorbing and removing hardness components (calcium ions and magnesium ions) contained in raw water such as tap water and groundwater with a cation exchange resin. In this ion exchange device, a water treatment mode in which raw water is introduced into a pressure tank to produce treated water, a regeneration mode in which a regeneration liquid is introduced into the pressure tank to restore ion exchange capacity, and a cleaning liquid (for example, raw water) is pressurized. A cleaning mode or the like for introducing the water into the tank and cleaning the inside is executed (hereinafter, the introduction of raw water into the pressure tank to produce treated water is also referred to as “water flow”).

  Among these, the cleaning mode is executed when the inside of the pressure tank is cleaned after the regeneration mode is executed, and also when the bacteria propagated in the pressure tank are forcibly removed. Conventionally, there has been proposed an ion exchange device configured to execute a cleaning mode when water passage to a pressure tank is not performed for a predetermined time (see Patent Document 1).

JP 2001-246376 A

  In the above ion exchanger, the time when there is no water flow to the pressure tank is counted as the accumulated time without water flow (hereinafter also referred to as “integrated time”), and the cleaning mode is executed when the accumulated time reaches a predetermined time. Is done. Moreover, in the said ion exchange apparatus, when water flow is performed during the measurement of the integration time, the integration time is reset. This is because the retained water staying in the pressure tank is replaced with new water by the water flow and discharged. In the state where the integration time has not reached the predetermined time, the number of general bacteria in the pressure tank satisfies the tap water standard of 100 CFU / mL or less. Therefore, the retained water discharged from the pressure tank by the inflow of new water can be supplied to the demand point as treated water having a quality suitable for drinking.

  In general, the number of bacteria discharged from the pressure tank varies depending on the instantaneous flow rate during water flow. That is, the larger the instantaneous flow rate during water flow, the greater the number of bacteria discharged per unit time, and the smaller the instantaneous flow rate during water flow, the smaller the number of bacteria discharged per unit time. In the conventional ion exchange device, when the water flow is resumed while the accumulated time is being measured, the accumulated time is reset regardless of the instantaneous flow rate of the water flow or the duration of the water flow. For this reason, even if water flow is resumed while the accumulated time is being measured, if the instantaneous flow rate of the water flow is small or the duration of water flow is short, the accumulated pressure in the pressure tank will be It is conceivable that many bacteria remain on the surface. Therefore, in the time zone when the amount of treated water is low, the number of general bacteria in the pressure tank exceeds the tap water standard during counting of the accumulated time, and water is passed before the washing mode is executed. There was danger.

  Therefore, an object of the present invention is to provide an ion exchange device that can always keep the number of general bacteria in a pressure tank below a tap water standard.

  The present invention includes a pressure tank in which an ion exchange resin bed is accommodated, a water treatment mode for producing treated water by introducing raw water into the pressure tank, and the ion exchange resin by introducing a regenerated solution into the pressure tank. A flow path switching means capable of switching to a flow path corresponding to each mode of a regeneration mode for regenerating the floor and a cleaning mode for cleaning the inside of the pressure tank by introducing a cleaning liquid into the pressure tank; and A flow rate measuring means for measuring a flow rate of water to be circulated; a time measuring means for starting time measurement of a non-water flow time when water flow to the pressure tank is stopped in the water treatment mode; and the non-water flow time. When the predetermined time set in advance is reached, a controller that switches the flow path switching means to a flow path corresponding to the cleaning mode and executes cleaning in the pressure tank, When the water flow to the pressure tank is resumed, the control unit, the water flow duration after the water flow is resumed, the instantaneous flow rate measured by the flow rate measuring means, and the exclusion coefficient corresponding to the instantaneous flow rate The cumulative number of bacteria that would have been excluded from the pressure tank is calculated based on the above, and when the cumulative number reaches a preset target cumulative number, the ion that resets the non-water passage time It relates to an exchange device.

  In addition, when the non-water passage time reaches the specified time and the cumulative number does not reach the target cumulative number, the control unit determines the target cumulative number and the cumulative number at that time. Is calculated as the residual number of bacteria, and in the cleaning mode executed after the lapse of the specified time, corresponds to the cleaning duration time after the start of cleaning, the instantaneous flow rate measured by the flow rate measuring means, and the instantaneous flow rate The cumulative number of bacteria that would have been eliminated from the pressure tank is calculated based on the elimination coefficient to be used, and when the cumulative number reaches the residual number, the washing in the pressure tank is terminated. Is preferred.

  In addition, when the cumulative number calculated in a certain water flow state does not reach the target cumulative number, the control unit calculates the difference between the target cumulative number and the calculated cumulative number as the residual number of bacteria. It is preferable to reset the non-water passage time when the cumulative number newly calculated in the subsequent water flow state reaches the remaining number.

  Moreover, it is preferable that the said control part sets the said target cumulative number according to the elapsed time in the water flow stop state after resetting the said non-water flow time.

  Moreover, it is preferable that the said control part sets the said target cumulative number according to the internal temperature of the said pressure tank.

  Moreover, it is preferable that the said control part sets the said target cumulative number according to the outer wall temperature of the said pressure tank.

  ADVANTAGE OF THE INVENTION According to this invention, the ion exchange apparatus which can always keep the number of general bacteria in a pressure tank below a tap water standard can be provided.

1 is an overall configuration diagram of a water softening device 1 according to an embodiment. It is a state transition diagram which shows the process in each operation mode and operation mode of the water softening apparatus. It is a figure which shows the open / close state of the process control valve 3 in each process. It is a functional block diagram which concerns on control of the water softening apparatus. It is a graph which shows the relationship between the instantaneous flow volume Q and the exclusion coefficient (eta). It is a flowchart which shows the process sequence when the water flow to the pressure tank 2 stops / restarts in the control apparatus 10 of the water softening apparatus 1. FIG. It is a flowchart which shows the process sequence when the water flow to the pressure tank 2 stops / restarts in the control apparatus 10 of the water softening apparatus 1. FIG. It is a flowchart which shows the process sequence when the water flow to the pressure tank 2 stops / restarts in the control apparatus 10 of the water softening apparatus 1. FIG. It is the graph which showed the growth rate of the number of general bacteria according to temperature.

  Hereinafter, a water softening apparatus 1 as a first embodiment of an ion exchange apparatus of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of a water softening device 1 as a first embodiment of an ion exchange device of the present invention.

  The hard water softening device 1 generates soft water by replacing hardness components contained in raw water such as tap water, ground water, and industrial water with sodium ions or potassium ions. The hard water softening device 1 is used for the purpose of supplying soft water to various demands such as potable water, and in order to supply safe soft water to the human body without propagation of germs, the stagnant water in the device is newly added. Has the function of replacing with water. The water softening device 1 is connected to residential buildings such as houses and condominiums, customer collection facilities such as hotels and public baths, and water-using equipment such as food processing devices and cleaning devices.

  As shown in FIG. 1, the water softening apparatus 1 of this embodiment mainly includes a pressure tank 2, a process control valve 3 as a flow path switching means, a salt water tank 4, and a raw water flow meter 61 as a flow rate measuring means. And a control device 5.

  The pressure tank 2 includes a pressure tank body 21 and a lid member 22. The pressure tank main body 21 is a bottomed cylindrical body having an opening at the top, and accommodates an ion exchange resin bed 211 made of cation exchange resin beads as a treatment material. The lid member 22 closes the opening at the top of the pressure tank body 21. The process control valve 3 is integrally attached to the lid member 22. Details of the pressure tank 2 will be described later.

  As will be described in detail later, the process control valve 3 lowers the raw water W1 by collecting the raw water W1 to the top screen 241 of the pressure tank 2 while collecting the raw water W1 on the bottom screen 242 in relation to sampling and regeneration. A flow of water (raw water W1, soft water W2) in the water treatment process ST1 for producing the soft water W2 as the treated water by generating a flow; while distributing the salt water W4 as the regenerating liquid to the top screen 241 of the pressure tank 2 The flow of the salt water W4 in the first regeneration process ST4 that generates a downward flow of the salt water W4 by collecting at the bottom screen 242 and regenerates the entire ion exchange resin bed 211; and the salt water W4 in the pressure tank 2 While the liquid is distributed to the bottom screen 242, the upward flow of the salt water W 4 is generated by collecting the liquid on the intermediate screen 243, and the ion exchange resin bed 21. A valve capable of switching the flow of salt water W4 in the second regeneration process ST6 to reproduce the lower part of.

  The salt water tank 4 stores salt water W4 as a regenerating liquid for regenerating the ion exchange resin bed 211. In the water softening device 1 using cation exchange resin beads, sodium chloride and potassium chloride aqueous solutions can be used as the regenerating solution. Details of the salt water tank 4 will be described later.

  The pressure tank 2 will be further described. The lid member 22 includes a first lid channel 221, a second lid channel 222, and a third lid channel 223 that supply and discharge fluid. Each of these lid flow paths 221, 222, and 223 is connected to various lines constituting the process control valve 3 as described later. “Line” is a general term for lines capable of flowing fluid such as flow paths, paths, and pipelines.

  In the pressure tank 2, a top screen 241 for preventing the resin beads from flowing out is provided on the lower surface side of the lid member 22 and on the top of the ion exchange resin bed 211. The top screen 241 has a large number of apertures smaller than the resin beads (the same applies to the bottom screen 242 and the intermediate screen 243 described later). The first lid channel 221 communicates with the inside of the pressure tank 2 via the top screen 241. The water distribution position and the water collection position by the top screen 241 are set near the top of the ion exchange resin bed 211. The top screen 241 functions as a top liquid distribution unit provided at the top of the ion exchange resin bed 211 and a top liquid collection unit provided at the top of the ion exchange resin bed 211.

  In the pressure tank 2, a first liquid collection and distribution pipe 231 that extends to the vicinity of the bottom of the pressure tank body 21 is connected to the second lid channel 222. A bottom screen 242 that prevents the resin beads from flowing out is provided at the lower end of the first liquid collection and distribution tube 231. The first liquid collection / delivery pipe 231 communicates with the second lid flow path 222. The water distribution position and the water collection position by the bottom screen 242 are set near the bottom of the ion exchange resin bed 211. The bottom screen 242 functions as a bottom liquid distribution unit provided at the bottom of the ion exchange resin bed 211 and a bottom liquid collection unit provided at the bottom of the ion exchange resin bed 211.

  In the pressure tank 2, a second liquid collection and distribution pipe 232 extending to the vicinity of the intermediate portion in the depth direction of the ion exchange resin bed 211 is connected to the third lid flow path 223. An intermediate screen 243 that prevents the resin beads from flowing out is provided at the lower end of the second liquid collection and distribution tube 232. The second liquid collection and distribution tube 232 communicates with the third lid channel 223. The water collection position by the intermediate screen 243 is set near the intermediate part in the depth direction of the ion exchange resin bed 211. That is, the intermediate screen 243 is provided in the intermediate portion in the depth direction of the ion exchange resin bed 211. The intermediate part screen 243 functions as an intermediate part liquid collecting part provided in an intermediate part in the depth direction of the ion exchange resin bed 211.

  The inner diameter of the second collection and distribution pipe 232 is set to be larger than the outer diameter of the first collection and distribution pipe 231. The axial centers of the first collection and distribution pipe 231 and the second collection and distribution pipe 232 are both set coaxially with the axial center of the pressure tank 2. That is, the first collection / distribution pipe 231 and the second collection / distribution pipe 232 form a double pipe structure in which the first collection / distribution pipe 231 is set as an inner pipe and the second collection / distribution pipe 232 is set as an outer pipe. The pressure tank 2 is attached.

  A raw water line L <b> 1 is connected to the first lid channel 221 through a process control valve 3. A soft water line L2 is connected to the second lid channel 222 via the process control valve 3. A fifth drain line L55 is connected to the third lid channel 223. The fifth drain line L55 is connected to the connection part J51 of the first drain line L51 inside the process control valve 3. The raw water line L1, the soft water line L2, and the first drainage line L51 extend to the outside of the process control valve 3. That is, each of the raw water line L 1, the soft water line L 2, and the first drainage line L 51 is provided inside the process control valve 3, and the remaining part is provided outside the process control valve 3.

  Although details will be described later, the control device 5 receives signals from a raw water flow meter 61, a salt water flow meter 62, and the like, which will be described later, and controls the process control valve 3 based on the input signals and the like.

  The process control valve 3 includes various lines, valves, and the like therein, and functions as a cleaning unit that cleans the inside of the pressure tank 2. Specifically, the process control valve 3 includes a raw water line L1, a soft water line L2, a dilution water line L3, a first salt water line L41, a second salt water line L42, and a third salt water line L43 as lines. The fourth saltwater line L44, the first drainage line L51, the second drainage line L52, the third drainage line L53, the fourth drainage line L54, the fifth drainage line L55, and the bypass line L6 are provided.

  A part of the raw water line L1 on the first lid channel 221 side also functions as a fifth salt water line L45. A part of the soft water line L2 on the second lid flow path 222 side also functions as the sixth salt water line L46. Raw water line L1, part of soft water line L2 (sixth salt water line L46 described later), part of fourth salt water line L44 (part between connecting part J21 and connecting part J42 in fourth salt water line L44), The three drainage lines L53, the second drainage line L52, and the first drainage line L51 function as cleaning means.

  The process control valve 3 is a raw water flow valve 311, a soft water flow valve 312, a bypass valve 313, an ejector valve 314, a third drain valve 315, a second drain valve 316, and a first drain valve as valves. A valve 317, a salt water valve 318, a first constant flow valve 322, and a second constant flow valve 34 are provided. The process control valve 3 includes an ejector strainer 321, an ejector 323, a first orifice 324, a second orifice 325, and a soft water strainer 33.

  In the raw water line L1, the raw water flow meter 61, the connection part J11, the raw water flow valve 311, the connection part J12, and the connection part J13 are sequentially provided from the supply side of the raw water W1 toward the first lid channel 221. Are provided. The part between the connection part J12 and the 1st cover flow path 221 in the raw | natural water line L1 functions also as the 5th salt water line L45. The raw water flow meter 61 is provided outside the process control valve 3.

  The raw water flow meter 61 can detect the flow rate of water flowing into the pressure tank 2 (inflow water amount or outflow water amount) by a flow pulse of the raw water W1, and functions as a flow rate measuring means. A flow rate detection signal from the raw water flow meter 61 is input to the control device 5. The raw water flow meter 61 is a flow sensor configured to be able to detect an instantaneous flow rate and an integrated flow rate. For example, a tangential flow rate sensor or an axial flow rate sensor can be used.

  The soft water line L2 is provided with a connection portion J21, a soft water strainer 33, a soft water flow valve 312 and a connection portion J22 in order from the second lid flow path 222 toward the supply destination of the soft water W2. The portion of the soft water line L2 between the second lid flow path 222 and the connection portion J21 also functions as the sixth salt water line L46. The soft water strainer 33 captures contaminants (crushed pieces of resin beads, dust, etc.) in the soft water W2 flowing through the soft water line L2 from the second lid flow path 222 toward the supply destination of the soft water W2.

  The dilution water line L3 is connected to the connection portion J11 of the raw water line L1 at its upstream end, and is connected to the primary side of the ejector 323 at its downstream end. In the dilution water line L3, an ejector strainer 321, a first constant flow valve 322, and an ejector 323 are provided in order from the upstream side (connection portion J11 side) to the downstream side (ejector 323 side).

  The ejector strainer 321 removes suspended substances contained in the dilution water composed of the raw water W1, and prevents the first constant flow valve 322 and the ejector 323 from being clogged. The first constant flow valve 322 adjusts the dilution water supplied to the ejector 323 to a predetermined flow rate. The ejector 323 is connected to the downstream end of the first salt water line L41 on the discharge side of the nozzle portion. The ejector 323 is configured to be capable of sucking salt water W4 (for example, a saturated aqueous solution of sodium chloride) from the salt water tank 4 using a negative pressure generated when dilution water (raw water W1) is discharged from the nozzle portion. ing. In the ejector 323, the salt water W4 from the salt water tank 4 is diluted to a predetermined concentration (for example, 8 to 12% by weight) with dilution water (raw water W1).

  The bypass line L6 connects the connection part J11 and the connection part J22. That is, the bypass line L6 connects the raw water line L1 and the soft water line L2.

  The regenerating liquid supply line is a line connecting the pressure tank 2 and the salt water tank (regenerating liquid tank) 4. In the first embodiment, two regeneration liquid supply lines are formed. The first regenerated liquid supply line includes a first salt water line L41, a second salt water line L42, a third salt water line L43, and a fifth salt water line L45 (part of the raw water line L1). The second regeneration liquid supply line is composed of a first salt water line L41, a second salt water line L42, a fourth salt water line L44, and a sixth salt water line L46 (a part of the soft water line L2).

  One end of the first salt water line L41 is disposed in the salt water tank 4. The other end portion of the first salt water line L41 is connected to the nozzle portion of the ejector 323. The first salt water line L41 is provided with a salt water flow meter 62 and a salt water valve 318 in order from the salt water tank 4 toward the ejector 323.

  The salt water flow meter 62 is provided outside the process control valve 3. The salt water flow meter 62 detects the flow rate of the salt water W4 flowing through the first salt water line L41 or the raw water W1 as makeup water. A detection signal from the salt water flow meter 62 is input to the control device 5. The salt water flow meter 62 is a flow sensor configured to be able to detect a bidirectional instantaneous flow rate and an integrated flow rate. For example, a tangential flow rate sensor, an axial flow rate sensor, a Karman vortex flow rate sensor, or the like can be used. it can.

  The upstream end portion of the third salt water line L43 and the upstream end portion of the fourth salt water line L44 are connected at the connection portion J41. The second salt water line L42 connects the secondary side of the ejector 323 and the connection portion J41.

  The downstream end of the third salt water line L43 is connected to the fifth salt water line L45 (raw water line L1) at the connection portion J12. A first orifice 324 is provided in the middle of the third salt water line L43. The downstream end of the fourth salt water line L44 is connected to the sixth salt water line L46 (soft water line L2) at the connection portion J21. The fourth salt water line L44 is provided with a second orifice 325 and an ejector valve 314 in order from the upstream side to the downstream side. In the second regeneration process ST6 and the second extrusion process ST7, which will be described later, the first orifice 324 and the second orifice 325 are used to supply the salt water W4 that is the regeneration solution or the raw water W1 that is the extrusion water to the second lid channel 222 and the first lid. This is for evenly distributing the flow paths 221.

  Various drainage water W5 is discharged from the downstream end of the first drainage line L51. The upstream end of the first drain line L51 is connected to the downstream end of the second drain line L52 and the downstream end of the fifth drain line L55 at the connection J51. The upstream end of the second drain line L52 is connected to the downstream end of the third drain line L53 and the downstream end of the fourth drain line L54 at the connection J52. The upstream end of the third drainage line L53 is connected to the fourth saltwater line L44 at the connection J42. The upstream end of the fourth drainage line L54 is connected to the raw water line L1 (fifth brine line L45) at the connection J13. The upstream end of the fifth drain line L55 is connected to the third lid channel 223.

  A second constant flow valve 34 is provided in the middle of the second drainage line L52. The second constant flow valve 34 adjusts the flow rate of the drainage W5 discharged from the pressure tank 2 and flowing through the second drainage line L52 to a predetermined range. A first drain valve 317 is provided in the middle of the third drain line L53. A third drain valve 315 is provided in the middle of the fourth drain line L54. A second drain valve 316 is provided in the middle of the fifth drain line L55.

  In the process control valve 3, the various valves 311 to 318 can employ various operating mechanisms and valve structures. Specifically, a lift type or diaphragm type channel opening / closing valve operated by a cam mechanism, a slide piston type channel opening / closing valve operated by a link mechanism, and the like are suitable.

  Next, the salt water tank 4 will be described. The salt water tank 4 includes a salt water tank body 41, a salt water well 42, and a salt water plate 44. The salt water tank main body 41 has a bottomed shape with an open top. The salt water well 42 has a cylindrical shape and is disposed inside the salt water tank main body 41. The salt water plate 44 divides the salt water storage part (lower part) and the storage part (upper part) of the regenerated salt 43 (for example, granular or pellet sodium chloride) into the upper and lower sides outside the salt water well 42. It consists of a plate.

  A salt water line arrangement space 46 is formed inside the salt water tank body 41 and inside the salt water well 42. In the salt water line arrangement space 46, an upstream end of the first salt water line L41 is arranged. A communication hole 45 is provided in the lower side wall of the salt water well 42. The communication hole 45 communicates between the salt water reservoir and the salt water line arrangement space 46. Therefore, the salt water W4 or makeup water can freely flow between the salt water storage section and the salt water line arrangement space 46.

  Next, the operation mode of the water softening device 1 and the process executed in the operation mode will be described with reference to FIGS. FIG. 2 is a state transition diagram showing operation modes of the water softening device 1 of the first embodiment and processes in each operation mode. FIG. 3 is a diagram showing an open / close state of the process control valve 3 in each process.

  The water softening device 1 operates as a water treatment mode for producing soft water W2 as treated water by introducing raw water W1 into the pressure tank 2 as an operation mode, and by introducing salt water W4 as a regenerated liquid into the pressure tank 2. A regeneration mode for regenerating the ion exchange resin bed 211, a cleaning mode for cleaning the inside of the pressure tank 2 by introducing the raw water W1 as a cleaning liquid into the pressure tank 2, and a water replenishment mode for replenishing the salt water tank 4 with the raw water W1. And a standby mode in which no fluid is introduced into the pressure tank 2. The flow of fluid in the processes executed between these operation modes and in the operation modes is controlled by the process control valve 3 as follows.

  As shown in FIG. 2, the process control valve 3 switches each operation mode and switches the process in each of these operation modes. Each operation mode is switched based on a predetermined transition condition (event). In FIG. 2, the arrow described between each operation mode shows the event E1-E8.

  Event E1 shows a case where the water treatment mode is shifted to the regeneration mode. As this transition condition, for example, when the current time is the time of the specified date (that is, the regeneration time), when the integrated amount of water (integrated usage) of the soft water W2 reaches a predetermined set amount, A case where the accumulated water passing time reaches a predetermined set time can be cited.

  Event E2 indicates a case where the regeneration mode is shifted to the cleaning mode. As this transfer condition, the case where the back washing process ST3 to 2nd extrusion process ST7 is completed can be mentioned, for example. Event E3 indicates a case where the mode is changed from the cleaning mode to the water replenishment mode. As the transition condition, for example, the operation mode immediately before the transition to the cleaning mode is the regeneration mode, and the cumulative circulation time of the cleaning liquid reaches a predetermined set time. Event E4 indicates a case where the water supply mode is shifted to the water treatment mode. As this transfer condition, for example, a case where the amount of refill water reaches a predetermined set amount can be mentioned.

Event E5 indicates a case where the water treatment mode is shifted to the cleaning mode. As the transition condition, for example, it can be as described below, a case where non-water passing time T ₁ is reached the prescribed time T _A. Event E6 indicates a case where the cleaning mode is shifted to the water treatment mode. As this transition condition, the operation mode immediately before shifting to the cleaning mode is the water treatment mode, and the number of bacteria discharged together with the cleaning liquid reaches the remaining number calculated at the timing of shifting to the cleaning mode, etc. (Described later).

  Event E7 shows a case where the cleaning mode is shifted to the standby mode. As this transition condition, for example, a case where the continuous detection time without the flow of the raw water W1 reaches a predetermined set time (when a water break occurs) can be mentioned. Event E8 indicates a case of transition from the standby mode to the cleaning mode. As this transfer condition, for example, a case where the continuous detection time with the circulation of the raw water W1 reaches a predetermined set time (when the water supply is restored) can be cited.

The process control valve 3 performs the following processes ST1 to ST10 in each operation mode while switching the flow path.
[ST1] Water treatment process (water softening process) for passing raw water W1 from the top to the bottom with respect to the entire ion exchange resin bed 211
[ST2] Strainer cleaning process for backwashing the soft water strainer 33 [ST3] Backwashing process for passing raw water W1 as the cleaning water from the bottom to the top with respect to the entire ion exchange resin bed 211 [ST4] Salt water as the regenerating solution First regeneration process for passing W4 from the top to the bottom with respect to the entire ion-exchange resin bed 211 [ST5] First to pass the raw water W1 as the extrusion water from the top to the bottom with respect to the entire ion-exchange resin bed 211 Extrusion process [ST6] A second regeneration process in which salt water W4 as a regeneration liquid is passed from the top to the bottom of the ion exchange resin bed 211 and from the bottom to the bottom of the ion exchange resin bed 211. [ST7] The raw water W1 as the extruded water is passed from the top to the bottom with respect to the upper part of the ion exchange resin bed 211, and the ion exchange resin bed 21 The second extrusion process [ST8] which passes from the bottom to the top of the lower part of the raw water W1 as the cleaning liquid (rinsing water) is passed from the top to the bottom with respect to the entire ion exchange resin bed 211, and Cleaning process (rinsing process or accumulated water discharge process) for cleaning (ion exchange resin bed 211)
[ST9] Replenishment process for supplying raw water W1 to salt water tank 4 [ST10] Standby process for waiting for supply of cleaning liquid

  The opening and closing of the valves 311 to 318 in the process control valve 3 is controlled by the control device 5 for each of the processes ST1 to ST10 as shown in FIG. As a result, in the pressure tank 2, a fluid flow is generated for each of the processes ST1 to ST10, or no fluid flow is generated. In the regeneration mode, a strainer cleaning process ST2 for back cleaning the soft water strainer 33 is provided before the reverse cleaning process ST3. This strainer cleaning process ST2 is not shown in FIG. 2 but is shown only in FIG. 3 for convenience of explanation. Further, a regeneration standby process (not shown) for waiting for the supply of the salt water W4 is provided between the strainer cleaning process ST2 and the back cleaning process ST3.

  Next, main control (operation) of the water softening device 1 according to the present embodiment will be described in detail. Hereinafter, in the present specification, discharging the retained water (residual water) in the pressure tank 2 to the outside of the system under a predetermined condition is also referred to as “performing stagnant water discharge” as appropriate. In each process ST2 to ST10 excluding the water treatment process ST1, the bypass valve 313 is open. Therefore, the excess raw water W1 that circulates upstream from the connection portion J11 in the raw water line L1 flows from the connection portion J12 to the bypass line L6, and to the demand point of the soft water W2 via the connection portion J22 and the soft water line L2. Temporarily supplied.

[Water treatment process ST1]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / close state indicated by ST1 in FIG. As a result, raw water W1 such as tap water, groundwater, and industrial water flowing through the raw water line L1 is supplied to the inside of the pressure tank main body 21 via the raw water line L1 and the first lid channel 221 and distributed from the top screen 241. Is done. The raw water W1 distributed from the top screen 241 passes through the ion exchange resin bed 211 in a downward flow. In the process, the hardness component of the raw water W1 is replaced with sodium ions, and the raw water W1 is softened.

  The treated water (soft water W <b> 2) that has passed through the ion exchange resin bed 211 is collected on the bottom screen 242 at the bottom of the pressure tank 2. Thereafter, the soft water W2 is supplied to a predetermined demand point of the soft water W2 through the first collection and distribution pipe 231, the second lid flow path 222, and the soft water line L2. When a predetermined amount of soft water W2 is collected and the ion exchange resin bed 211 cannot replace the hardness component, a regeneration process is performed.

[Strainer cleaning process ST2]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / closed state indicated by ST2 in FIG. As a result, the raw water W1 flowing through the raw water line L1 is the raw water line L1, the connecting portion J11, the bypass line L6, the connecting portion J22, the soft water line L2, the soft water strainer 33, the connecting portion J21, the fourth salt water line L44, the connecting portion J42, It is discharged out of the system through the third drainage line L53, the second drainage line L52, and the first drainage line L51. In this process, the soft water strainer 33 is back-washed by the raw water W1 flowing through the soft water strainer 33 from the secondary side to the primary side, and contaminants captured by the soft water strainer 33 are discharged out of the system together with the raw water W1. .

[Regeneration process]
In the regeneration process, in order to recover the hardness component removal ability (ion exchange capacity) of the ion exchange resin bed 211, the reverse cleaning process ST3 to the water replenishment process ST9 are sequentially performed (see FIG. 2). Among these processes, the reverse cleaning process ST3 is well known as disclosed in the patent document and the like, and thus the description thereof is omitted.

[Regeneration process: first regeneration process ST4]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / close state shown in ST4 of FIG. As a result, the raw water W1 flowing upstream from the connection portion J11 in the raw water line L1 is supplied to the primary side of the ejector 323 via the dilution water line L3 as the dilution water of the salt water W4. At this time, the suspended substances in the raw water W1 are removed by the ejector strainer 321. The flow rate of the raw water W1 is adjusted to a predetermined range by the first constant flow valve 322.

  In the ejector 323, a negative pressure is generated on the discharge side of the nozzle portion (reference number omitted) by the passage of the raw water W1, and the first salt water line L41 also has a negative pressure. As a result, the saturated salt water W4 in the salt water tank 4 is sucked into the ejector 323 via the first salt water line L41. In the ejector 323, the saturated salt water W4 is diluted to a predetermined concentration using the raw water W1 as dilution water, and salt water W4 as a regenerating solution is prepared. The prepared salt water W4 passes through the second salt water line L42, the third salt water line L43, the fifth salt water line L45 (a part of the raw water line L1), and the first lid channel 221 to the inside of the pressure tank body 21. And water is distributed from the top screen 241.

  The salt water W4 distributed from the top screen 241 passes through the ion exchange resin bed 211 in a downward flow, and regenerates the entire ion exchange resin bed 211 in the process. The regenerated liquid (salt water W 4) that has passed through the ion exchange resin bed 211 is collected on the bottom screen 242 at the bottom of the pressure tank 2. The used salt water W4 includes the first collection and distribution pipe 231, the second lid flow path 222, the soft water line L2, the connection portion J21, the fourth salt water line L44, the connection portion J42, the third drainage line L53, and the second drainage line L52. And it is discharged out of the system via the first drainage line L51.

The first regeneration process ST4 is so-called cocurrent regeneration. In this co-current regeneration, when the supply capacity of the salt water W4, which is the regeneration liquid, reaches the set regenerant amount (= regeneration level × ion exchange resin bed capacity), the process ends and the process proceeds to the first extrusion process ST5. . The amount of the regenerant, the concentration of the regenerated liquid, the specific gravity of the regenerated liquid, and the supply capacity of the regenerated liquid have the following relationship.
Regenerant amount = concentration of regenerated solution x specific gravity of regenerated solution x supply capacity of regenerated solution (1)

[Regeneration process: first extrusion process ST5]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / closed state indicated by ST5 in FIG. As a result, the raw water W1 flowing upstream from the connection portion J11 in the raw water line L1 is supplied to the primary side of the ejector 323 through the dilution water line L3 as the extruded water. The raw water W1 that has passed through the ejector 323 passes through the second salt water line L42, the third salt water line L43, the fifth salt water line L45 (a part of the raw water line L1), and the first lid channel 221, and the pressure tank body 21 , And water is distributed from the top screen 241.

  The raw water W1 as the extrusion water distributed from the top screen 241 passes through the ion exchange resin bed 211 in a downward flow while extruding the salt water W4 as the regeneration solution supplied in advance, and then continues to the ion exchange resin bed 211. Play. The regenerated liquid (salt water W4) and the extruded water (raw water W1) that have passed through the ion exchange resin bed 211 are collected on the bottom screen 242 at the bottom of the pressure tank 2. The used salt water W4 and raw water W1 are the first collection and distribution pipe 231, the second lid flow path 222, the soft water line L2, the connection portion J21, the fourth salt water line L44, the connection portion J42, the third drainage line L53, the second. It is discharged out of the system through the drainage line L52 and the first drainage line L51.

[Regeneration process: second regeneration process ST6]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / closed state indicated by ST6 in FIG. As a result, the raw water W1 flowing upstream from the connection portion J11 in the raw water line L1 is supplied to the primary side of the ejector 323 via the dilution water line L3 as the dilution water of the salt water W4.

  The salt water W4 prepared in the ejector 323 is supplied to the pressure tank main body via the second salt water line L42, the third salt water line L43, the fifth salt water line L45 (a part of the raw water line L1), and the first lid channel 221. 21 and supplied from the top screen 241.

  The salt water W4 distributed from the top screen 241 passes through the ion exchange resin bed 211 in a downward flow, and regenerates the upper part of the ion exchange resin bed 211 in the process. The regenerated liquid (salt water W4) that has passed through the upper part of the ion exchange resin bed 211 is collected on the intermediate screen 243 at the intermediate part in the depth direction of the pressure tank 2. The used salt water W4 is discharged out of the system through the second collection and distribution pipe 232, the third lid channel 223, the fifth drainage line L55, the connecting portion J55, and the first drainage line L51.

  Further, the salt water W4 prepared in the ejector 323 is diverted from the connection portion J41 of the second salt water line L42, and the fourth salt water line L44, the sixth salt water line L46 (part of the soft water line L2), and the second lid channel. The water is supplied to the inside of the pressure tank main body 21 through 222, and is distributed from the bottom screen 242 through the first liquid collection and distribution pipe 231.

  The salt water W4 distributed from the bottom screen 242 passes through the ion exchange resin bed 211 in an upward flow, and regenerates the lower part of the ion exchange resin bed 211 in the process. The regenerated liquid (salt water W4) that has passed through the lower part of the ion exchange resin bed 211 is collected on the intermediate screen 243 at the intermediate part in the depth direction of the pressure tank 2. The used salt water W4 is discharged out of the system through the second collection and distribution pipe 232, the third lid channel 223, the fifth drainage line L55, the connecting portion J55, and the first drainage line L51.

  The second regeneration process ST6 is so-called split flow regeneration in which partial cocurrent regeneration and partial countercurrent regeneration are performed simultaneously. In the partial countercurrent regeneration, the lower part of the ion exchange resin bed 211 that is difficult to be regenerated in the first regeneration process ST4 is efficiently regenerated. In the second regeneration process ST6, the flow below the ion exchange resin bed 211 is suppressed by the downward flow of the salt water W4 as the regeneration liquid. When the supply capacity of the salt water W4, which is the regenerating liquid, reaches the set amount of the regenerating agent, the process ends and the process proceeds to the second extrusion process ST7. The relationship between the amount of the regenerant, the concentration of the regenerating solution, the specific gravity of the regenerating solution, and the supply capacity of the regenerating solution is as shown by the above-described equation (1).

[Regeneration process: second extrusion process ST7]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / closed state indicated by ST7 in FIG. As a result, the raw water W1 flowing upstream from the connection portion J11 in the raw water line L1 is supplied to the primary side of the ejector 323 through the dilution water line L3 as the extruded water. The raw water W1 that has passed through the ejector 323 is supplied as extrusion water to the primary side of the ejector 323 via the dilution water line L3. The raw water W1 that has passed through the ejector 323 passes through the second salt water line L42, the third salt water line L43, the fifth salt water line L45 (a part of the raw water line L1), and the first lid channel 221, and the pressure tank body 21 , And water is distributed from the top screen 241.

  The raw water W1 as the extrusion water distributed from the top screen 241 passes through the ion exchange resin bed 211 in a downward flow while extruding the salt water W4 as the regeneration solution supplied in advance, and then continues to the ion exchange resin bed 211. Play the top of. The regenerated liquid (salt water W4) and the extruded water (raw water W1) that have passed through the upper portion of the ion exchange resin bed 211 are collected on the intermediate screen 243 at the intermediate portion in the depth direction of the pressure tank 2. The used salt water W4 and raw water W1 are discharged out of the system through the second collection and distribution pipe 232, the third lid channel 223, the fifth drain line L55, the connecting portion J55, and the first drain line L51.

  The raw water W1 that has passed through the ejector 323 is diverted from the connection portion J41 of the second salt water line L42, and the fourth salt water line L44, the sixth salt water line L46 (a part of the soft water line L2), and the second lid channel 222. Is supplied to the inside of the pressure tank main body 21, and is distributed from the bottom screen 242 through the first liquid collection and distribution pipe 231.

  The raw water W1 as the extrusion water distributed from the bottom screen 242 passes through the ion exchange resin bed 211 in an upward flow while extruding the salt water W4 as the regeneration solution supplied in advance, and then continues to the ion exchange resin bed 211. Play the bottom of. The regenerated liquid (salt water W4) and the extruded water (raw water W1) that have passed through the lower part of the ion exchange resin bed 211 are collected on the intermediate screen 243 at the intermediate portion in the depth direction of the pressure tank 2. The used salt water W4 and raw water W1 are discharged out of the system through the second collection and distribution pipe 232, the third lid channel 223, the fifth drain line L55, the connecting portion J55, and the first drain line L51. In the regeneration mode described above, the salt water W4 as the regeneration liquid and the raw water W1 as the extrusion water also function as a cleaning liquid for cleaning the inside of the pressure tank 2.

[Cleaning process ST8]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / close state indicated by ST8 in FIG. As a result, raw water W1 such as tap water, groundwater, and industrial water flowing through the raw water line L1 is supplied to the inside of the pressure tank main body 21 via the raw water line L1 and the first lid channel 221 and distributed from the top screen 241. Is done. The raw water W1 distributed from the top screen 241 passes through the ion exchange resin bed 211 in a downward flow, and cleans the ion exchange resin bed 211. That is, the raw water W1 functions as a cleaning liquid for cleaning the inside of the pressure tank 2 (ion exchange resin bed 211). The hardness component of the raw water W1 is replaced with sodium ions in the process in which the raw water W1 passes through the ion exchange resin bed 211, and the raw water W1 is softened.

  The treated water (soft water W <b> 2) that has passed through the ion exchange resin bed 211 is collected on the bottom screen 242 at the bottom of the pressure tank 2. Thereafter, the soft water W2 passes through the first collection and distribution pipe 231, the second lid channel 222, the sixth salt water line L46, the fourth salt water line L44, the third drain line L53, the second drain line L52, and the first drain line L51. Then, it is discharged out of the system as drainage W5.

  In this specification, when the operation mode immediately before the transition to the cleaning process ST8 is the regeneration mode, the cleaning process ST8 is referred to as a “rinse process”, and the operation mode immediately before the transition to the cleaning process ST8 is the water treatment. In the case of the mode or the standby mode, it will be referred to as “stagnant water discharge process”.

[Replenishment process ST9]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to the open / close state shown in ST9 of FIG. As a result, the raw water W1 flowing upstream from the connection portion J11 in the raw water line L1 is supplied to the primary side of the ejector 323 via the dilution water line L3 as make-up water. The makeup water from the ejector 323 is supplied into the salt water tank 4 via the first salt water line L41.

[Standby process ST10]
In response to a command signal from the control device 5, the valves 311 to 318 of the process control valve 3 are set to an open / closed state indicated by ST10 in FIG. As a result, raw water W1 such as tap water, ground water, and industrial water flowing through the raw water line L1 flows from the connecting portion J11 to the bypass line L6, and temporarily passes through the connecting portion J22 and the soft water line L2 to the demand point of the soft water W2. Supplied. Further, no fluid such as raw water W1 is introduced into the pressure tank 2.

  Next, with reference to FIG. 4, the function which concerns on control of the water softening apparatus 1 which concerns on this embodiment is demonstrated. The control device 5 controls each part in the water softening device 1. The control device 5 includes a microprocessor (not shown) including a CPU and a memory. As shown in FIG. 4, the control device 5 is electrically connected to the process control valve 3. Further, the control device 5 is electrically connected to the raw water flow meter 61 and the salt water flow meter 62 in the hard water softening device 1 and receives a flow detection signal from each flow meter. Although not shown, the control device 5 is electrically connected to an operation unit having a display panel for displaying reproduction time and the like, buttons that can be operated by the user, and the like.

  As shown in FIG. 4, the control device 5 includes a valve control unit 51, a timer unit 52, and a memory unit 53. The valve control unit 51 controls the opening and closing of the valves 311 to 318 in the process control valve 3 in accordance with a control program stored in the memory unit 53, thereby causing the water softening device 1 to operate in a required operation mode (state shown in FIG. 2). Switch to the flow path corresponding to the transition diagram).

  The valve control unit 51 sets the operation mode according to the occurrence of the events E1 to E8 described above. Then, the valve control unit 51 sends a drive signal to the process control valve 3 so that the valves 311 to 318 necessary for execution of the process in each operation mode stored in the memory unit 53 are opened and closed (see FIG. 3). Output to. Thereby, in the process control valve 3, the flow path corresponding to the set operation mode is switched.

In the water softening device 1, when the water treatment mode is set by the valve control unit 51, the water can be passed through the pressure tank 2. In the water treatment mode, when the user opens a faucet or the like at the sampling point of the soft water W2, water is passed through the pressure tank 2. On the other hand, when water flow to the pressure tank 2 is stopped and no flow pulse input from the raw water flow meter 61 is continued for a predetermined time (for example, 30 seconds), a non-water flow time is measured in the time measuring unit 52 (described later). Timing of T ₁ [minutes] starts. Here, the predetermined time is a time for confirming that water is not used at the demand point. Non water passing time T ₁ refers continuously to the pressure tank 2 to the water flow time (i.e., the duration of the water flow stops).

Valve control unit 51, when the non-water passing time T ₁ which is measured by the time measuring unit 52 reaches a predetermined reference time T _A is forcibly removed the bacteria present in the interior of the pressure tank 2 For this purpose, the operation mode is switched from the water treatment mode to the washing mode to execute the accumulated water discharge process, and the inside of the pressure tank 2 is washed with fresh water. The valve control unit 51 ends the cleaning mode when the amount of water from which all 100 CFU / mL bacteria (described later) have been removed is passed after the start of the cleaning mode (residual water discharge process).

Further, when the water flow to the pressure tank 2 is resumed and the state in which the flow rate pulse input from the raw water flow meter 61 is continued for a predetermined time (for example, 10 seconds), the water flow duration T ₂ Time measurement starts. Here, the predetermined time is a time for confirming that water is used at the demand point. The valve control unit 51 then passes the continuous flow time T ₂ after the resumption of water flow measured by the time measuring unit 52, the instantaneous flow rate Q measured by the raw water flow meter 61, and the exclusion coefficient η (described later) corresponding to the instantaneous flow rate. Based on the above, the cumulative number (total number of excluded bacteria) N of bacteria that would have been excluded from the pressure tank 2 during the water flow duration T ₂ is calculated by the following equation. Then, when the cumulative number N reaches the preset target cumulative number N _A [CFU / mL], the time counting unit 52 resets the non-water passage time T ₁ .
N [CFU / mL] = T ₂ [min] × Q [L / min] × η [CFU / mL / L]
(2)

In the present embodiment, as the number of bacteria allowed the pressure tank 2, the upper limit of the number of general bacteria in tap water based on the (100 CFU / mL) were employed, and sets the target cumulative number _{N A} to 100 CFU / mL . Valve control unit 51, in the water treatment mode, if the amount of water 100 CFU / mL of bacteria is eliminated, all have been passed through, that is, when the cumulative number N has reached the target cumulative number N _A is the timer unit 52 non water passing time T ₁ is reset.

In addition, the valve control unit 51 stores the cumulative number N calculated up to that point in the memory unit 53 when the water flow is stopped while the amount of water from which all 100 CFU / mL bacteria are excluded is not passed. Let In this case, the non-water flow measurement of the time T ₁ by the time counting unit 52 continues.

The exclusion coefficient η shown in the above formula (2) means the number of bacteria that can be eliminated by passing 1 L of water. The exclusion coefficient η increases as the instantaneous flow rate Q of the raw water W1 during water flow increases. For example, when the instantaneous flow rate Q during water flow is 14 L / min, 5 minutes are required as the water flow duration T ₂ in order to eliminate all 100 CFU / mL bacteria. In this case, the exclusion coefficient η is 1.43. On the other hand, when the instantaneous flow rate Q during water flow is 7 L / min, 12 minutes are required as the water flow duration T ₂ in order to eliminate all 100 CFU / mL bacteria. In this case, the exclusion coefficient η is 1.19.

  The memory unit 53 described later stores the instantaneous flow rate Q and the exclusion coefficient η in association with each other. For example, when the fluctuation range of the instantaneous flow rate Q is 7 L / min to 14 L / min and the exclusion coefficient η is calculated every 1 L / min, 13 sets of data in which the instantaneous flow rate Q and the exclusion coefficient η are associated with each other are obtained. Stored in the memory unit 53.

  As shown in FIG. 5, the instantaneous flow rate Q and the exclusion coefficient η are in a proportional relationship. Therefore, an approximate value of the exclusion coefficient η can be calculated by multiplying (or dividing) the instantaneous flow rate Q by a preset correction coefficient. The graph shown in FIG. 5 is an example in which the size of the pressure tank 2 is an outer diameter of 10 × height of 19 (inch), the internal volume is 18.6L, and the amount of ion exchange resin is 15L.

  Depending on the specifications of the pressure tank 2 and the amount of ion exchange resin, the relationship between the exclusion coefficient η and the instantaneous flow rate Q may not be proportional as shown in FIG. In that case, for example, instead of the correction coefficient described above, a conversion formula for calculating the exclusion coefficient η from the instantaneous flow rate Q can be used.

The valve control unit 51 will be described again. Valve control unit 51, when the non-water passing time T ₁ which is measured by the time measuring unit 52 has reached a predetermined time T _A (i.e., transition timing to the washing mode), the cumulative number stored in the memory unit 53 if N has reached the target cumulative number N _a, calculates the difference between the cumulative number N at that time as the target cumulative number N _a as residual bacterial counts R [CFU / mL]. The valve control unit 51, in the cleaning mode to be executed after the specified time T _A has elapsed (accumulated water discharge process), washing duration after cleaning start T _3, the raw water flow meter 61 by the measured instantaneous flow rate Q, and Based on the exclusion coefficient η corresponding to this instantaneous flow rate Q, the cumulative number N of bacteria that would have been eliminated from the pressure tank 2 during the washing duration T ₃ is calculated by the following equation. Then, when the cumulative number N reaches the remaining number R, the valve control unit 51 ends the cleaning mode.
N [CFU / mL] = T ₃ [min] × Q [L / min] × η [CFU / mL / L]
(3)

For example, when the non-water passing time T ₁ which is measured by the time measuring unit 52 has reached a predetermined time T _A, the cumulative number N is assumed to be 50. In this case, the remaining number R (target cumulative number N _A -cumulative number N) is 50. Then, when the instantaneous flow rate Q flushing mode is performed at 7L / minute (excluding coefficient eta = 1.19), when the cleaning duration T ₃ has elapsed 6 minutes, cumulative number N reaches the number of residual R. Accordingly, the control unit 51 ends the cleaning mode after 6 minutes from the start of the cleaning mode (retained water discharge process).

The valve control unit 51, when the cumulative number N calculated at a certain water flow state has not reached the target cumulative number N _A is the difference between the target cumulative number N _A and already calculated the cumulative number N of bacteria Calculated as the residual number R. The valve control unit 51, the cumulative number N which is newly calculated in the subsequent water flow state when it reaches the residual number R is to reset the non-water passage time T ₁ in the timer unit 52.

For example, if the user uses the soft water W2, and the instantaneous flow rate Q is 7 L / min (exclusion coefficient η = 1.19) and the water flow state a in which the water flow duration T ₂ is 4 minutes occurs, The cumulative number N calculated in the water flow state a is 33.3 [CFU / mL]. In this case, the remaining number R at the time when the water flow state a is completed is 66.7 [CFU / mL]. When the user uses the soft water W2 again, it is assumed that the water flow state b occurs when the instantaneous flow rate Q is 14 L / min (exclusion coefficient η = 1.43) and the water flow duration T ₂ exceeds 3.33 minutes. The cumulative number N newly calculated in the water flow state b is 66.7 [CFU / mL] or more. Then, when the water flow duration time T ₂ exceeds 3.33 minutes, the newly calculated cumulative number N (the number of bacteria eliminated in the water flow state b) is the residual number R (the water flow state a is excluded). The number of bacteria that was not reached). Therefore, the valve control unit 51, in the water flow state b, when the water flow duration T ₂ exceeds 3.33 minutes, thereby resetting the non-water passage time measured T ₁ by the timing unit 52.

As described above, in this embodiment, 100 CFU as the bacterial number allowed in the pressure tank 2, maximum number of general bacteria in tap water based on the (100 CFU / mL) were employed, the target cumulative number _{N A} / ML. In the example in which the size of the pressure tank 2 is an outer diameter of 10 × height of 19 (inch), the internal volume is 18.6 L, and the amount of ion exchange resin is 15 L, water is passed through the pressure tank 2 when the temperature is 20 ° C. When 12 hours elapse in the absence of water, the number of general bacteria in the pressure tank 2 grows to 100 CFU / mL.

The target cumulative number N _A, when the elapsed time after the non-water passage time T ₁ is reset at timing unit 52 is less than 12 hours, be changed according to the elapsed time in the water flow stopped Good. For example, after resetting the non-water passage time T ₁ in the timer unit 52, when there is water flow at the time of the lapse of 6 hours, 10 [CFU / mL] in water passing through the start as the target cumulative number N _A Set. In this case, the valve control unit 11, when the cumulative number N calculated after water flow start has reached 10, to reset the non-water passage time T ₁ in the timer unit 52. Further, after resetting the non-water passage time T ₁ in the timer unit 52, if there is water flow at the time has elapsed for 9 hours, 32 to water passing through the start as the target cumulative number N _A [CFU / mL] Set. In this case, the valve control unit 11, when the cumulative number N calculated after passing water starts reached 32, to reset the non-water passage time T ₁ in the timer unit 52.

Note that in some water flow conditions c after the non-water passage time T ₁ is reset, when the cumulative number N has not reached the target cumulative number N _A is the cumulative number N calculated by the water flow state c It is subtracted from the target cumulative number N _a that is set at the beginning of the next water flow state d. For example, after the non-water passage time T ₁ is reset, occur water flow state c at the time of 3 hours has passed, and 3 [CFU / mL] as a target cumulative number N _A is set to its start. If the cumulative number N calculated by the water flow state c is 2, the reset cumulative number N <target cumulative number N _A so non water passing time T ₁ is not. Then, 6 hours from the reset (i.e., 3 hours from the end of the water passage state c) and the water flow state d Upon expiration occurs, as the target cumulative number N _A is 10 [CFU / mL] was set at the start To do. In this case, since the cumulative number N calculated in advance is 2, the valve control unit 11 performs the non-water passage time when the cumulative number N calculated in the water flow state d reaches 8 (10-2). the T ₁ to reset.

When the water flow to the pressure tank 2 is stopped and the flow pulse input from the raw water flow meter 61 is not input for a predetermined time (for example, 30 seconds) in the water treatment mode, the time measuring unit 52 does not pass the water flow time T. Start timing ₁ In addition, the timekeeping unit 52 resumes water flow when the water flow to the pressure tank 2 is resumed in the water treatment mode and the flow pulse input from the raw water flow meter 61 continues for a predetermined time (for example, 10 seconds). to start the counting of the water flow duration T ₂ of the post. Further, timer unit 52, in the cleaning mode (accumulated water discharge process), the water flow of the washing liquid (raw water W1) into the pressure tank 2 is started, to start the counting of the cleaning duration after cleaning start T ₃ .

  Regardless of the operation mode before the transition to the cleaning mode, the time measuring unit 52 resets the time count until that time when returning from the cleaning mode to the water treatment mode. In addition, when the reset command is given from the valve control unit 51, the time measuring unit 52 resets the time measured until then.

The memory unit 53 is a storage device for storing a control program or the like for operating the water softening device 1. The control program is a program for controlling the process control valve 3 so as to shift the operation mode in accordance with the occurrence of the events E1 to E8 described above and to execute a prescribed processing process in each operation mode. Further, the memory unit 53 stores data related to the execution conditions of each processing process. In addition, the memory unit 53 includes a non-water passage time T ₁ , a water flow duration T ₂ , a cleaning duration time T ₃ , a specified time T _A , an instantaneous flow rate Q (actual measurement value), an exclusion coefficient η, and a cumulative number N (calculation). Data) is stored.

  Next, in the water softening device 1 of the present embodiment, the operation when the water flow to the pressure tank 2 is stopped / resumed will be described with reference to FIGS. FIGS. 6-8 is a flowchart which shows the process sequence in case the water flow to the pressure tank 2 stops / restarts in the control apparatus 5 of the water softening apparatus 1. FIG. The processing of the flowcharts shown in FIGS. 6 to 8 is executed by the valve control unit 51 based on the control program stored in the memory unit 53. Moreover, the process of the flowchart shown in FIGS. 6-8 is repeatedly performed during the driving | operation of the water softening apparatus 1. FIG.

  In step ST101 shown in FIG. 6, the valve control unit 51 determines whether or not the water flow to the pressure tank 2 is stopped during the execution of the water treatment mode (water treatment process ST1). The valve control unit 51 determines that “water flow is stopped” when a state in which there is no flow rate pulse input from the raw water flow meter 61 continues for a predetermined time (for example, 30 seconds). In step ST101, when it is determined by the valve control unit 51 that the water flow to the pressure tank 2 has stopped (YES), the process proceeds to step ST102. In Step ST101, when it is determined by the valve control unit 51 that water flow to the pressure tank 2 is not stopped (NO), the process returns to Step ST101.

Step ST 102: (Step ST 101 YES), the valve control unit 51 issues a count start command to the timer unit 52 to start the counting of the non-water passage time _{T 1.} In step ST 103, the valve control unit 51 determines whether or not the non-water passage time T ₁ which is measured by the timer unit 52 has reached a predetermined time T _A. In this step ST 103, the valve control unit 51, when the non-water passing time _{T 1} is is determined to have reached the specified time _{T A} (YES), the process proceeds to step ST 104 (the occurrence of an event E5). Further, in step ST 103, the valve control unit 51, when the non-water passing time _{T 1} is is determined defined not reached the time _{T A} and (NO), the process proceeds step ST113 (see FIG. 7).

  In step ST <b> 104 (step ST <b> 103: YES), the valve control unit 51 determines whether or not the cumulative number N of data is present (present) in the memory unit 53. The cumulative number N stored in the memory unit 53 is calculated in the previous water flow state. In step ST104, when the valve control unit 51 determines that the accumulated number N of data exists in the memory unit 53 (YES), that is, N> 0, the process proceeds to step ST105. In step ST104, when the valve control unit 51 determines that there is no accumulated number N of data in the memory unit 53 (NO), that is, N = 0, the process proceeds to step ST110.

Step ST105: In (step ST 104 YES), the valve control unit 51 calculates the target cumulative number _{N A,} the difference between the stored cumulative number N in the memory unit 53 as a residual number R. In step ST106, the valve controller 51 shifts the operation mode of the process control valve 3 from the water treatment mode to the cleaning mode. Thereby, as shown in FIG. 2, the stagnant water discharge process ST8 is executed. Accumulated water discharge process ST8 is started and the supply of the cleaning liquid (raw water W1) into the pressure tank 2 is started, the time counting unit 52, time measurement of the cleaning duration after cleaning start T ₃ is started. In step ST 107, the valve control unit 51, based on the equation (3), calculates the cumulative number N of bacteria that would have been excluded from the pressure tank 2 during the cleaning duration T _3.

  In step ST108, the valve control unit 51 determines whether or not the cumulative number N calculated in step ST107 has reached the residual number R calculated in step ST105. In step ST108, when the valve control unit 51 determines that the cumulative number N has reached the remaining number R (YES), the process proceeds to step ST109 (occurrence of event E6). In step ST108, if the valve control unit 51 determines that the cumulative number N has not reached the remaining number R (NO), the process returns to step ST107.

In step ST109, the valve control unit 51 ends the cleaning mode, and returns the operation mode of the process control valve 3 to the water treatment mode. Thereby, water treatment process ST1 is performed. The valve control unit 51, at the end of the accumulated water discharge process ST8, thereby resetting the non-water passage time measured T ₁ by the timing unit 52.

On the other hand, in step ST110 (step ST104: NO), the valve control unit 51 shifts the operation mode of the process control valve 3 from the water treatment mode to the cleaning mode. Thereby, as shown in FIG. 2, the stagnant water discharge process ST8 is executed. Accumulated water discharge process ST8 is started and the supply of the cleaning liquid (raw water W1) into the pressure tank 2 is started, the time counting unit 52, time measurement of the cleaning duration after cleaning start T ₃ is started. In step ST111, the valve control unit 51, based on the equation (3), calculates the cumulative number N of bacteria that would have been excluded from the pressure tank 2 during the cleaning duration T _3.

In step ST 112, the valve control unit 51 determines the cumulative number N calculated in step ST111 is whether reaches the target cumulative number _{N A.} In this step ST 112, the valve control unit 51, when the cumulative number N is determined to have reached the target cumulative number _{N A} (YES), the process proceeds to step ST 109 (the occurrence of an event E6). Further, in step ST 112, the valve control unit 51, when the cumulative number N is determined not to reach the target cumulative number _{N A} (NO), the process returns to step ST111.

Step ST104~ step ST112, when the non-water passing time _{T 1} is reached the prescribed time _{T A,} that is, a process executed when an event E5 occurs.

In step ST113 shown in FIG. 7 (step ST103: NO), the valve control unit 51 determines whether or not water flow to the pressure tank 2 has been resumed during execution of the water treatment mode (water treatment process ST1). . The valve controller 51 determines that “water flow is resumed” when a state in which there is a flow pulse input from the raw water flow meter 61 continues for a predetermined time (for example, 10 seconds). In step ST113, when it determines with the water flow to the pressure tank 2 having been restarted by the valve control part 51 (YES), a process transfers to step ST114. In Step ST113, when it is determined by the valve control unit 51 that water passage to the pressure tank 2 has not been resumed (NO), the process returns to Step ST103. Incidentally, when the water flow is resumed, the timer unit 52, measurement of the water flow after the resumption of water flow duration T ₂ is started.

  In step ST <b> 114 (step ST <b> 113: YES), the valve control unit 51 determines whether or not the cumulative number N of data is present (present) in the memory unit 53. The cumulative number N stored in the memory unit 53 is calculated in the previous water flow state. In step ST114, when the valve control unit 51 determines that the accumulated number N of data exists in the memory unit 53 (YES), that is, N> 0, the process proceeds to step ST115. In step ST114, when the valve control unit 51 determines that the cumulative number N does not exist in the memory unit 53 (NO), that is, N = 0, the process proceeds to step ST121 (see FIG. 8). To do.

Step ST115: In (step ST114 YES), the valve control unit 51 calculates the target cumulative number _{N A,} the difference between the stored cumulative number N in the memory unit 53 as a residual number R. In step ST116, the valve control unit 51 calculates the cumulative number N of would have been excluded from the pressure tank 2 between the water passage time duration T ₂ bacteria.

  In step ST117, the valve control unit 51 determines whether or not the cumulative number N calculated in step ST116 has reached the residual number R calculated in step ST115. In step ST117, when the valve control unit 51 determines that the cumulative number N has reached the remaining number R (YES), the process proceeds to step ST118. If the valve control unit 51 determines in step ST117 that the cumulative number N has not reached the remaining number R (NO), the process proceeds to step ST119.

Step ST 118: (Step ST117 YES), the valve control unit 51 resets the non-water passage time measured _{T 1} by the timing unit 52, and ends the present process.

  On the other hand, in step ST119 (step ST117: NO), the valve control unit 51 determines whether or not the water flow to the pressure tank 2 is stopped during the execution of the water treatment mode (water treatment process ST1). As in step ST101 described above, the valve control unit 51 determines that “water flow is stopped” when a state in which no flow rate pulse input from the raw water flow meter 61 is continued for a predetermined time (for example, 30 seconds). In step ST119, when the valve control unit 51 determines that water flow to the pressure tank 2 has stopped (YES), the process proceeds to step ST120. In step ST119, when the valve control unit 51 determines that the water flow to the pressure tank 2 is not stopped (NO), the process returns to step ST116.

  In step ST120 (step ST119: YES), the valve control unit 51 causes the memory unit 53 to store the cumulative number N calculated up to that point. After step ST120, the process proceeds to step ST103 (see FIG. 6).

Step ST121 shown in FIG. 8: (Step ST114 NO), the valve control unit 51 calculates the cumulative number N of would have been excluded from the pressure tank 2 between the water passage time duration _{T 2} bacteria.

In step ST122, the valve control unit 51 determines the cumulative number N calculated in step ST121 is whether reaches the target cumulative number _{N A.} In this step ST122, the valve control unit 51, when the cumulative number N is determined to have reached the target cumulative number _{N A} (YES), the processing proceeds step ST118 to (Reset non water passage time _{T 1)} . Further, in step ST122, the valve control unit 51, when the cumulative number N is determined not to reach the target cumulative number _{N A} (NO), the process proceeds to step ST123.

  In step ST123 (step ST122: NO), the valve control unit 51 determines whether or not water flow to the pressure tank 2 is stopped during the execution of the water treatment mode (water treatment process ST1). As in step ST101 described above, the valve control unit 51 determines that “water flow is stopped” when a state in which no flow rate pulse input from the raw water flow meter 61 is continued for a predetermined time (for example, 30 seconds). In step ST123, when the valve control unit 51 determines that water flow to the pressure tank 2 is stopped (YES), the process proceeds to step ST120. In step ST123, when the valve control unit 51 determines that the water flow to the pressure tank 2 is not stopped (NO), the process returns to step ST121.

Step ST113~ step ST123, when the non-water passing time _{T 1} is not reached the specified time _{T A,} that is, a process executed when an event E5 is not generated.

  According to the water softening device 1 according to the present embodiment described above, for example, the following effects are exhibited.

In the water softening device 1, when the water flow to the pressure tank 2 is stopped, and the start timing of the non-water passage time T _1, the non-water passing time cleaning when T ₁ is reached the prescribed time T _A mode ( A stagnant water discharge process) is performed. Further, in the water softening device 1, when the water flow to the pressure tank 2 is resumed, the water flow continuation time T ₂ to the pressure tank 2, the instantaneous flow rate Q at the time of water flow, and the exclusion corresponding to the instantaneous flow rate Q based on the coefficient eta, calculated cumulative number N of bacteria that would have been excluded from the pressure tank 2, when the cumulative number N has reached the target cumulative number N _a that has been set in advance, the non-water passage time T ₁ is reset.

Therefore, in the water softening device 1, even if passed through is resumed during counting of non-water passage time T _1, if the number of bacteria is eliminated, which corresponds from the pressure tank 2 to the target cumulative number N _A, non-passage never water time T ₁ is reset. Therefore, according to the hard water softening device 1, the number of general bacteria in the pressure tank 2 can always be kept below the tap water standard.

In the water softening device 1, when the non-water passing time T ₁ is reached the prescribed time T _A, if the cumulative number N has not reached the target cumulative number N _A is the target cumulative number N _A that the difference between the cumulative number N at the time is calculated as the residual number R of bacteria, in a cleaning mode executed after a predetermined time T _a, the cleaning duration after cleaning start T _3, the instantaneous flow rate of the raw water W1 as washing liquid Based on Q and the exclusion coefficient η corresponding to the instantaneous flow rate Q, the cumulative number N of bacteria that would have been excluded from the pressure tank 2 is calculated, and when this cumulative number N reaches the residual number R The cleaning mode is terminated. Therefore, according to the water softening apparatus 1, the number of general bacteria in the pressure tank 2 can be made substantially zero while suppressing the time required for the accumulated water discharge process and the amount of water in the cleaning liquid.

In the water softening device 1, when the cumulative number N calculated in a certain water flow state has not reached the target cumulative number N _A is the difference between the target cumulative number N _A and the already determined cumulative number N calculated as the residual number R of bacteria, cumulative number N which is newly calculated at the subsequent water flow state when it reaches the residual number R is a non-water passage time T ₁ is reset. Therefore, in the water softening device 1, since the number of bacteria that increase or decrease to the water treatment mode is finely controlled, the number of general bacteria in the pressure tank 2 does not shift to the washing mode in a state that exceeds the tap water standard. . Therefore, according to the water softening apparatus 1, the inside of the pressure tank 2 can be washed at an appropriate timing, and wasteful water consumption can be suppressed.

In the water softening device 1, the target cumulative number N _A in response to the elapsed time of the non-water passage time T ₁ at stopping feeding water state after reset is set. According to this, since the target cumulative number N _A corresponding to the number of bacteria that would grow with the passage of the residence time is set, while minimizing the time required for the accumulated water discharging process and the amount of water of the cleaning solution, sanitary Soft water W2 can be secured.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to embodiment mentioned above, It can implement with a various form.

For example, in the present embodiment has been described for an example of setting the target cumulative number N _A according to the elapsed time of the non-water passage time T ₁ with water flow stopped after the reset. Not limited thereto, also it is may be possible to set the target cumulative number N _A according to the internal temperature of the pressure tank 2, sets the target cumulative number N _A in accordance with the outer wall temperature of the pressure tank 2 Good.

FIG. 9 is a graph showing the number of general bacteria growing in the pressure tank 2 by temperature. As shown in FIG. 9, it can be seen that the number of general bacteria increases as the temperature rises. In addition, when the elapsed time is 1 to 5 hours, there is no significant difference in the number of general bacteria grown depending on the temperature. However, when the elapsed time reaches 6 hours or more, particularly 12 hours, the difference in the number of growth of general bacteria is about 5.6 times at maximum. In general, by executing the cleaning mode, the specified time T _A in the case of forcibly removed breeding bacteria into the pressure tank 2, 6 to 12 hours is set. Therefore, by setting the target cumulative number N _A according to the internal temperature or the outside wall temperature of the pressure tank 2 can be kept constantly below the tap water based on the number of general bacteria in the pressure tank 2.

Incidentally, a method of measuring the internal temperature of the pressure tank 2 can be compared to the method for measuring the external wall temperature of the pressure tank 2, it sets the target cumulative number N _A more accurately. However, in the method of measuring the internal temperature of the pressure tank 2, it may be difficult to install a temperature sensor inside the pressure tank 2. In this case, by adopting the method of measuring the external wall temperature of the pressure tank 2, while facilitating installation of the temperature sensor, it is possible to set the accurate target cumulative number N _A.

1 Water softener (ion exchanger)
2 Pressure tank 3 Process control valve (flow path switching means)
5 Control Device 51 Valve Control Unit 52 Timekeeping Unit (Timekeeping Means)
53 Memory part 61 Raw water flow meter (flow rate measuring means)
211 ion exchange resin floor

In the above ion exchanger, the time when there is no water flow to the pressure tank is counted as the accumulated time without water flow (hereinafter also referred to as “integrated time”), and the cleaning mode is executed when the accumulated time reaches a predetermined time. Is done. Moreover, in the said ion exchange apparatus, when water flow is performed during the measurement of the integration time, the integration time is reset. This is because the retained water staying in the pressure tank is replaced with new water by the water flow and discharged. In a state where the integrated time has not reached the predetermined time, the general bacterial number of the pressure tank satisfies the following 100 CFU / mL of tap water quality standards. Therefore, the retained water discharged from the pressure tank by the inflow of new water can be supplied to the demand point as treated water having a quality suitable for drinking.

In general, the number of bacteria discharged from the pressure tank varies depending on the instantaneous flow rate during water flow. That is, the larger the instantaneous flow rate during water flow, the greater the number of bacteria discharged per unit time, and the smaller the instantaneous flow rate during water flow, the smaller the number of bacteria discharged per unit time. In the conventional ion exchange device, when the water flow is resumed while the accumulated time is being measured, the accumulated time is reset regardless of the instantaneous flow rate of the water flow or the duration of the water flow. For this reason, even if water flow is resumed while the accumulated time is being measured, if the instantaneous flow rate of the water flow is small or the duration of water flow is short, the accumulated pressure in the pressure tank will be It is conceivable that many bacteria remain on the surface. Therefore, the usage periods of low processing water, the number of general bacteria in the pressure tank during counting of the accumulated time exceeds the tap water quality standards, passed through a line before yet cleaning mode is executed There was a risk of being caught.

Accordingly, the present invention aims at providing an ion exchange device that can be kept constantly below the tap water quality standards the number of bacteria in the pressure tank.

According to the present invention, it is possible to provide an ion exchange device that can be kept constantly below the tap water quality standards the number of bacteria in the pressure tank.

In the present embodiment, as the number of bacteria allowed the pressure tank 2, the upper limit of the number of general bacteria in tap water quality standards of (100 CFU / mL) were employed, by setting the target cumulative number _{N A} to 100 CFU / mL Yes. Valve control unit 51, in the water treatment mode, if the amount of water 100 CFU / mL of bacteria is eliminated, all have been passed through, that is, when the cumulative number N has reached the target cumulative number N _A is the timer unit 52 non water passing time T ₁ is reset.

As described above, in the present embodiment, as the number of bacteria allowed the pressure tank 2, the upper limit value of the number of general bacteria in tap water cytoplasm relative to the (100 CFU / mL) were employed, the target cumulative number N _A It is set to 100 CFU / mL. In the example in which the size of the pressure tank 2 is an outer diameter of 10 × height of 19 (inch), the internal volume is 18.6 L, and the amount of ion exchange resin is 15 L, water is passed through the pressure tank 2 when the temperature is 20 ° C. When 12 hours elapse in the absence of water, the number of general bacteria in the pressure tank 2 grows to 100 CFU / mL.

Therefore, in the water softening device 1, even if passed through is resumed during counting of non-water passage time T _1, if the number of bacteria is eliminated, which corresponds from the pressure tank 2 to the target cumulative number N _A, non-passage never water time T ₁ is reset. Therefore, according to the Water Softener 1, it can be kept always below tap water quality standards the number of bacteria in the pressure tank 2.

In the water softening device 1, when the cumulative number N calculated in a certain water flow state has not reached the target cumulative number N _A is the difference between the target cumulative number N _A and the already determined cumulative number N calculated as the residual number R of bacteria, cumulative number N which is newly calculated at the subsequent water flow state when it reaches the residual number R is a non-water passage time T ₁ is reset. Therefore, in the water softening device 1, the number of bacteria increases and decreases in the water treatment mode is control over, that the number of general bacteria in the pressure tank 2 is shifted to the cleaning mode with more than tap water quality standards Absent. Therefore, according to the water softening apparatus 1, the inside of the pressure tank 2 can be washed at an appropriate timing, and wasteful water consumption can be suppressed.

FIG. 9 is a graph showing the number of general bacteria growing in the pressure tank 2 by temperature. As shown in FIG. 9, it can be seen that the number of general bacteria increases as the temperature rises. In addition, when the elapsed time is 1 to 5 hours, there is no significant difference in the number of general bacteria grown depending on the temperature. However, when the elapsed time reaches 6 hours or more, particularly 12 hours, the difference in the number of growth of general bacteria is about 5.6 times at maximum. In general, by executing the cleaning mode, the specified time T _A in the case of forcibly removed breeding bacteria into the pressure tank 2, 6 to 12 hours is set. Therefore, by setting the target cumulative number N _A according to the internal temperature or the outside wall temperature of the pressure tank 2 can be kept constantly below the tap water quality standards the number of bacteria in the pressure tank 2.

Claims (6)

A pressure tank containing an ion exchange resin bed;
A water treatment mode in which treated water is produced by introducing raw water into the pressure tank, a regeneration mode in which the ion exchange resin bed is regenerated by introducing a regeneration liquid into the pressure tank, and a cleaning liquid is introduced into the pressure tank. A flow path switching means capable of switching to a flow path corresponding to each mode of the cleaning mode for cleaning the inside of the pressure tank,
A flow rate measuring means for measuring a flow rate of water flowing through the pressure tank;
In the water treatment mode, when the water flow to the pressure tank is stopped, time measuring means for starting time measurement of the non-water flow time;
A controller that performs cleaning in the pressure tank by switching the flow path switching means to a flow path corresponding to the cleaning mode when the non-water passage time reaches a predetermined time set in advance; Prepared,
When the water flow to the pressure tank is resumed, the control unit is based on the water flow continuation time after the water flow is resumed, the instantaneous flow rate measured by the flow rate measuring means, and the exclusion coefficient corresponding to the instantaneous flow rate. Calculating the cumulative number of bacteria that would have been excluded from the pressure tank, and resetting the non-water passage time when the cumulative number reaches a preset target cumulative number,
Ion exchange device. When the non-water passage time reaches the specified time and the cumulative number does not reach the target cumulative number, the control unit determines the difference between the target cumulative number and the cumulative number at that time. Is calculated as the number of remaining bacteria, and in the cleaning mode executed after the lapse of the specified time, the cleaning duration time after the start of cleaning, the instantaneous flow rate measured by the flow rate measuring means, and the exclusion corresponding to the instantaneous flow rate Based on the coefficient, calculate the cumulative number of bacteria that would have been excluded from the pressure tank, and when the cumulative number reaches the residual number, the cleaning in the pressure tank is terminated.
The ion exchange apparatus according to claim 1. When the cumulative number calculated in a certain water flow state does not reach the target cumulative number, the control unit calculates a difference between the target cumulative number and the calculated cumulative number as a residual number of bacteria. When the cumulative number newly calculated in the subsequent water flow state reaches the remaining number, the non-water flow time is reset.
The ion exchange apparatus according to claim 1 or 2. The control unit sets the target cumulative number according to an elapsed time in a water flow stop state after resetting the non-water flow time.
The ion exchange apparatus as described in any one of Claims 1-3. The control unit sets the target cumulative number according to the internal temperature of the pressure tank.
The ion exchange apparatus as described in any one of Claims 1-4. The control unit sets the target cumulative number according to the outer wall temperature of the pressure tank.
The ion exchange apparatus as described in any one of Claims 1-4.

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