JP2012170834A - Water treatment system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water treatment system capable of saving water by reducing the amount of blow water discharged, while preventing the quality of treated water from deteriorating.SOLUTION: The water treatment system 1 includes a raw water line L1 through which raw water flows, a water treatment device 10 for producing treated water by performing a predetermined process on the raw water supplied from the raw water line L1, a treated water line L2 through which treated water flows, a treated water tank 15 having a water-level gauge 17 for detecting the level of treated water and storing the treated water for supply to the outside, a treated water blow line L6 connected to the treated water line L2 for discharging the treated water outside of the system, and a controller 35 for controlling the blow of the treated water. If the level of water in the treated water tank 15 is below a prescribed level when treated water blowing is performed at predetermined timing, the controller 35 controls to perform treated water passage for causing the treated water to pass through the treated water tank 15 instead of the treated water blowing.

Description

  The present invention relates to a water treatment system that performs predetermined water treatment on raw water and supplies treated water to water-using equipment.

  For example, water-using equipment that uses a large amount of water, such as thermal equipment such as steam boilers, hot water boilers, and cooling towers, parts washing equipment used in semiconductor manufacturing, and medical equipment washing equipment used in medical settings has been widely used. ing.

  In these water-using devices, if raw water such as industrial water, tap water, and well water is used as it is, not only the prescribed performance cannot be obtained due to adhesion of impurities, generation of scale, occurrence of corrosion, etc., but the device itself May break down. For this reason, conventionally, raw | natural water is processed with water treatment apparatuses, such as an activated carbon filtration apparatus, a soft water apparatus, a membrane filtration apparatus, and a deaeration apparatus, and the treated water after a process is supplied to water use apparatus.

  The water treatment system which has such a water treatment apparatus is disclosed by the following patent documents 1, 2, for example.

JP 2003-190973 A JP 2009-221733 A

  By the way, the use aspect of the treated water by a user is various. For example, in a factory, the use of treated water is stopped for a long time on nights and holidays when the factory is not in operation, and the water supply standby time in the water treatment system also becomes longer. For this reason, there existed a possibility that the quality of the treated water might deteriorate while the treated water stayed in the filtration device or the like for a long time.

  In order to cope with such a problem, the conventional water treatment system is configured to discharge the stagnant water from the treated water blow line at a predetermined timing to the outside of the system so that the treated water stayed in the water treatment apparatus for a long time. There is a system that does not supply water to equipment that uses water.

  However, if such a treated water blow is performed, a large amount of water will be thrown away. For example, in a water treatment system having a supply capacity of 10 t / h, if treated water is blown for 12 minutes, as much as 2 t of water will be discarded.

  The present invention has been made in view of such problems, and a water treatment system capable of saving water while suppressing the amount of blown water discharged while preventing deterioration of the quality of treated water supplied from the water treatment system. The purpose is to provide.

  In order to solve the above problems, a water treatment system according to the present invention includes a raw water line through which raw water flows, and water that is connected to the raw water line and that performs a predetermined treatment on the raw water supplied from the raw water line to produce treated water. A treatment water line connected to a treatment device, a treatment water line through which the treatment water flows, and a treatment water tank connected to the treatment water line and stored for supplying the treatment water to the outside. A water comprising a treated water tank having a water level meter for detecting the water level, a treated water blow line connected to the treated water line and discharging treated water out of the system, and a control device for controlling the treated water blow In the treatment system, the control device performs the treatment water blow to discharge the treatment water from the treatment water blow line to the outside of the system at a predetermined timing, and if the water level in the treatment water tank is less than the predetermined water level, Instead of Risui blow, and controls to perform the processing water through the water which passed through the treated water into the treated water tank.

  According to the water treatment system of the present invention, it is possible to save water while suppressing the amount of blown water discharged while preventing deterioration of the quality of the supplied treated water.

Drawing 1 is a mimetic diagram showing roughly the composition of the water treatment system concerning this embodiment. FIG. 2 is a flowchart showing the flow of treatment water flow according to the present embodiment.

  Hereinafter, a water treatment system according to an embodiment of the present invention will be described with reference to the drawings. Drawing 1 is a mimetic diagram showing roughly the composition of the water treatment system concerning this embodiment.

  As shown in FIG. 1, the water treatment system 1 includes a raw water line L1, a filtration device 10, a treated water line L2, a treated water tank 15, a treated water supply line L3, a backwash water supply line L5, a treated water blow line L6, A drug addition device 25, a water quality meter 30, a flow meter 31, and a control device 35 are provided.

  The raw water line L1 is connected to a water supply source such as ground water or tap water, and supplies these to the water treatment system 1 as raw water. The raw water line L1 is provided with a raw water pump 5 and a raw water valve 6. The raw water pump 5 sends the raw water toward the filtration device 10, and the raw water valve 6 opens and closes the raw water line L1.

  The filtration device 10 is connected to the downstream side of the raw water line L1, and produces treated water by capturing suspended substances contained in the raw water with a filter medium. The filtration device 10 includes a filtration tower 11 having a filter medium therein, a control valve 12, and a drain line L4, and is configured so that the filter medium can be periodically cleaned.

  The control valve 12 is a valve that controls the switching of the flow path of water (raw water, treated water, backwash water or rinsing water at the time of cleaning the filter medium) flowing into or out of the filter tower 11. The drainage line L4 is connected to the control valve 12, and backwash water and rinsing water at the time of cleaning the filter medium are discharged from the drainage line L4 to the outside of the system.

  The treated water line L2 is connected to the downstream side of the filtration device 10, and treated water produced by the filtration device 10 is supplied from the control valve 12 to the treated water line L2. A treated water passage valve 14 is installed in the treated water line L2, and the treated water passage valve 14 opens and closes the treated water line L2.

  The treated water blow line L6 is connected to the treated water line L2 on the upstream side of the treated water flow valve 14, and discharges the accumulated water in the filtration tower 11 outside the system for a predetermined time at a predetermined timing. Used when performing water blow. A treated water blow valve 24 for opening and closing the treated water blow line L6 is installed in the treated water blow line L6.

  The treated water tank 15 is connected to the downstream side of the treated water line L2, and stores treated water introduced through the treated water line L2. The treated water tank 15 includes a tank body 16 for storing treated water, and a water level meter 17 for measuring the water level H of treated water stored in the tank body 16.

The water level meter 17 is an electrode-type water level meter, and is configured to be able to detect three liquid levels: a lower limit water level H _L , an intermediate water level H _M , and an upper limit water level H _H. The lower limit water level H _L is a water level that should be kept at least in the treated water tank 15 in preparation for supply to an external water-using device. That is, the lower limit water level _HL is a water level that serves as an index for starting the supply of treated water to the treated water tank 15, and when the control device 35 detects the lower limit water level _HL , the treated water is supplied to the treated water tank 15. Is started.

The upper limit water level H _H is a value that defines the upper limit water level of the treated water accumulated in the tank body 16, and serves as an index for stopping the supply of treated water to the treated water tank 15. That is, the control unit 35 when detecting the upper limit level H _H, the supply of treated water to the treated water tank 15 is stopped.

Intermediate level H _M is the intermediate level between the upper limit water level H _H a lower limit level H _L, a level indicative of the time of performing the process water through the water, which will be described later in place of the treated water blown described above. The intermediate water level H _M as long the water level in the tank body 16 below the intermediate level H _M, so that the processing water through water is the extent that the treated water does not overflow in the tank body 16 be performed for a predetermined period of time The predetermined water level is set in advance.

  The treated water supply line L3 is connected to the downstream side of the treated water tank 15, and the treated water stored in the treated water tank 15 is supplied to an external water use device via the treated water supply line L3. A treated water feed pump 20 for sending treated water is installed in the treated water supply line L3.

  The upstream side of the backwash water supply line L5 is connected to the treated water tank 15, and the downstream side is connected to the raw water line L1 between the raw water valve 6 and the filtration device 10. A backwash water supply pump 21 and a backwash valve 22 are installed in the backwash water supply line L5. Backwash water at the time of cleaning the filter medium of the filter device 10 is supplied to the filter device 10 through the backwash water supply line L5.

  The chemical addition device 25 is connected to the raw water line L1 between the raw water pump 5 and the raw water valve 6, and a predetermined chemical agent such as an aggregating agent or an oxidizing agent for assisting the trapping of suspended substances in the filtration device 10. Is added to the raw water. The drug addition device 25 includes a drug storage unit 26 for storing a drug and a drug addition pump 27 for sending the drug to the raw water line L1.

  The water quality meter 30 is connected to the treated water line L2 upstream from the branch point of the treated water blow line L6, and the quality of treated water flowing through the treated water line L2 (for example, turbidity, chromaticity, residual chlorine concentration). , Hardness, electrical conductivity, etc.). The flow meter 31 is connected to the treated water line L2 between the water quality meter 30 and the branch point of the treated water blow line L6, and measures the flow rate of treated water flowing through the treated water line L2.

  The control device 35 includes a raw water pump 5, a raw water valve 6, a control valve 12, a treated water passage valve 14, a treated water feed pump 20, a backwash water supply pump 21, a backwash valve 22, a treated water blow valve 24, and a chemical addition. It is connected to the pump 27 and controls these drives in order to realize the above-described functions and the like. Moreover, the control apparatus 35 is connected with the water level meter 17, the water quality meter 30, and the flow meter 31, and receives these measurement data.

  The configuration of the water treatment system 1 has been described in detail above. Subsequently, in the water treatment system 1, the treated water is discharged from the treated water blow line L6 at a predetermined timing to prevent deterioration of the quality of the treated water. The flow of processing in the case of performing so-called treated water flow, in which treated water is passed to the treated water tank 15 instead of the treated water blow, will be described with reference to the drawings.

  FIG. 2 is a flowchart showing the flow of treatment water flow according to the present embodiment. Various processes described below are realized by the control device 35 executing a processing program stored in an internal memory to control each member constituting the water treatment system 1.

  When performing the treatment water flow, first, in S10, it is monitored whether or not it is the timing of performing the regular treatment water blow. Here, in the present embodiment, so-called regular treated water blow and pre-feed water pretreated water blow are performed as treated water blow for discharging the accumulated water in the filtration tower 11. Periodic treated water blow is treated water blow that is carried out periodically at regular intervals.

  This regular treated water blow is performed every predetermined time (for example, every 4 hours) in a time zone such as a nighttime when the operation of the factory is stopped and the supply of treated water is stopped. According to the periodic treated water blow, the treated water is blown at regular intervals to prevent the water in the filtration tower 11 from staying and to supply treated water of a certain quality or higher to the treated water tank 15. Can do.

  On the other hand, the pre-water supply treated water blow is a treated water blow performed before the first water supply after no water is supplied from the water treatment system 1 for a certain period of time. This pre-water supply treatment water blow is performed, for example, on the morning of the holiday when the operation of the factory is stopped for a long time (for example, 24 hours), before the first treatment water is supplied. According to the pre-water supply treated water blow, even when the water supply is not performed for a long time, high-quality treated water can be reliably supplied by performing the treated water blow before the water supply.

  In the present embodiment, the supplied treated water is maintained at a higher quality by combining the regular treated water blow and the pre-feed water pretreated water blow. However, in this embodiment, as described later, treated water is passed instead of the regular treated water blow, and the treated water blow before water supply is always performed. This is because, in the case of the pre-feed water pretreatment water blow, there is a possibility that the quality of the staying water staying in the filtration tower 11 for a long time has deteriorated to the extent that it does not satisfy the predetermined standard.

In S10, when it is determined that the execution timing of the periodic process water blown predetermined time elapses, the process proceeds to S11, the water level H in the treated water tank 15 measured by the water level indicator 17 is less than the intermediate level H _M It is determined whether or not.

In S11, if H <H _M , it is determined that there is a certain amount of free space to put the treated water in the treated water tank 15, and the process proceeds to S12 where treated water is passed instead of the treated water blow. . Specifically, similarly to the supply of the treated water to the treated water tank 15 via the normal treated water line L2, the treated water flow valve 14 is opened with the treated water blow valve 24 closed, and the filtration device 10 The treated water produced in (1) is supplied to the treated water tank 15.

Processing the water water flow is initiated at S12, since the water level in the treated water tank 15 is gradually increased, or subsequently, in S14, the water level H of the treated water tank 15 is not equal to or larger than the upper limit level H _H Be monitored. If H ≧ H _H , further water flow to the treated water tank 15 is not desirable, so the treated water flow is terminated and the process proceeds to S13 to switch to regular treated water blow.

In the case of H <H _H , the treated water flow is continued, and in S15, it is monitored whether the scheduled time for performing the regular treated water blow has elapsed. This scheduled scheduled time for treatment water blow is a time set in advance to blow a desired amount of the treatment water (the amount of water to be replaced in the filtration tower 11), and is set to 10 minutes, for example. Note that the flow rate may be set instead of the time, and in this case, the flow meter 31 monitors whether the planned flow rate has been reached.

If the scheduled time has not elapsed, the process returns to S14, and S14 and S15 are repeated until H ≧ H _H (S14) or until the scheduled time elapses (S15). In S15, when the scheduled time has elapsed, the treated water flow is terminated.

On the other hand, in S11, if the H ≧ H _M, as the free space in the treated water tank 15 is insufficient, the process proceeds to S13, to implement the normal periodic treated water blow. In S16, it is monitored whether the scheduled time for performing the periodic treated water blow has elapsed, and when the scheduled time has elapsed, the scheduled treated water blow is terminated.

In addition, as described above, when the process proceeds from S14 to S13 and is switched from the middle of the treated water passage to the treated water blow, the time when the treated water is conducted and the time when the treated water blow is conducted. Are added together to make the determination in S16. In this way, in any case of treated water flow only, treated water blow only, or a combination of treated water flow and treated water blow, the same scheduled blow time is carried out, and the same amount in the filtration tower 11 The water will be replaced.

  As mentioned above, although this embodiment was described in detail, even if it is a case where the water in the filtration tower 11 is discharged | emitted and replaced in order to prevent deterioration of the quality of the treated water according to this embodiment, a treated water tank. When the water level in 15 is lower than the predetermined water level and there is a vacancy, the discharged water is not discharged out of the system from the treated water blow line L6, but is passed to the treated water tank 15. So you can save water without wasting water.

Further, in the present embodiment, when the water level in the treated water tank 15 in the middle of performing a process water through the water exceeds the upper water level H _H, it is configured to switch the treated water blowing, treated water Problems such as overflow of water in the tank 15 can be prevented.

This also sets the setting of the intermediate water level H _M as high as possible water level, it is possible to increase the water-saving effect. In addition, the scheduled time for periodic treated water blow can also be set to be optimal for the installation environment such as the quality of raw water without worrying about overflow of the treated water tank 15 due to the passage of treated water.

  As mentioned above, although embodiment of this invention was described in detail, embodiment of this invention is not limited to the form mentioned above, A various deformation | transformation is possible within the range which does not deviate from the main point of this invention. For example, in this embodiment, an electrode-type water level meter that detects the water level step by step is adopted as the water level meter, but other methods such as a capacitance-type water level meter that can continuously measure the water level are used as appropriate. The water level gauge can be used. If the water level meter can continuously measure the water level, the setting of the intermediate water level can be easily changed as appropriate.

  Moreover, in the said embodiment, although the filtration apparatus was mentioned as an example and demonstrated as a water treatment apparatus, it is not limited to this, A deaeration apparatus, a soft water apparatus, a membrane filtration apparatus (MF membrane, UF membrane, RO membrane) Even if it is a water treatment system which has other water treatment apparatuses, such as), the present invention is applicable if it is a water treatment system which has a treated water blow line.

  Further, in the above embodiment, the water level in the treated water tank is monitored during the treated water flow, and when the water level exceeds the upper limit water level, it is configured to switch to the treated water blow. You may comprise so that treated water flow may be continued during the scheduled time of regular process water blow, without monitoring a water level. However, in this case, the intermediate water level, which is an index for passing the treated water, should be lowered with a margin in advance so that the treated water tank will not become full even if the treated water is passed as scheduled. It is desirable to set it.

  In the above embodiment, when a predetermined intermediate water level is set and the water level in the treated water tank is lower than the predetermined intermediate water level when the treated water is blown, treated water is passed instead. However, the treated water may be passed when the intermediate water level is lower than the upper limit water level without setting the intermediate water level. However, in this case, the treated water tank may become full immediately due to the treated water flow, so the water level in the treated water tank was monitored during the treated water flow and exceeded the upper limit water level. In some cases, it is desirable to control to switch to treated water blow.

  In the above embodiment, the treated water is passed only in place of the regular treated water blow, but the treated water may be passed in place of the treated water blow before water supply. However, in order to prevent the treated water that has deteriorated due to staying for a long time from being fed, the treated water should be passed instead of the pretreated water blow only when the water quality measured by the water quality meter satisfies the specified water quality. Is desirable.

  Even if treated water is used instead of regular treated water blow, if the water quality is measured with a water quality meter and the regular treated water blow is controlled as it is when the water quality is poor, higher quality can be achieved. Treated water can be provided. On the other hand, if the water quality is good, the water-saving effect can be further enhanced by controlling so as to shorten the scheduled time for the regularly treated water blow. As a result, even when the degree of deterioration of the accumulated water in the water treatment device changes due to fluctuations in the raw water quality, it is possible to provide higher quality treated water while enhancing the water saving effect.

DESCRIPTION OF SYMBOLS 1 Water treatment system L1 Raw water line 5 Raw water pump 6 Raw water valve 10 Filtration apparatus 11 Filtration tower 12 Control valve L2 Treated water line 14 Treated water flow valve 15 Treated water tank 16 Tank body 17 Water level meter L3 Treated water supply line 20 Treated water Water supply pump L4 Drainage line L5 Backwash water supply line 21 Backwash water supply pump 22 Backwash valve L6 Process water blow line 24 Process water blow valve 25 Drug addition device 26 Drug reservoir 27 Drug addition pump 30 Water quality meter 31 Flow meter 35 Control device

Claims (4)

Raw water line through which raw water flows,
A water treatment apparatus that is connected to the raw water line and that performs a predetermined treatment on the raw water supplied from the raw water line to produce treated water;
A treated water line connected to the water treatment device and through which the treated water flows;
A treated water tank connected to the treated water line and stored for supplying the treated water to the outside, the treated water tank having a water level meter for detecting the water level of the stored treated water;
A treated water blow line connected to the treated water line and discharging the treated water out of the system;
In a water treatment system comprising a control device for controlling the blow of treated water,
When the water level in the treated water tank is lower than the predetermined water level when performing the treated water blow for discharging the treated water from the treated water blow line to the outside of the system at a predetermined timing, the control device performs the treatment. Instead of water blow, the water treatment system is controlled so as to perform treated water flow for passing the treated water to the treated water tank.   2. The water treatment system according to claim 1, wherein the control device performs control so as to pass the treated water in place of the periodic treated water blow periodically performed at predetermined time intervals. The water level gauge includes a lower limit water level that serves as an index for starting the supply of the treated water to the treated water tank, an upper limit water level that serves as an index for stopping the supply of the treated water to the treated water tank, and the upper limit water level. A predetermined intermediate water level set between the lower limit water level and configured to be detectable at least;
The water treatment system according to claim 1 or 2, wherein the control device performs control so that the treated water is passed when a water level in the treated water tank is equal to or lower than the intermediate water level.   The control device controls to terminate the treated water flow and perform the treated water blow when the water level gauge detects the upper limit water level during the treatment water flow. The water treatment system according to claim 3.

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