JP2019018185A - Water treatment system controller - Google Patents

Abstract

A control device for accurately monitoring chlorine leakage to a filtration membrane device with a relatively simple circuit.
SOLUTION: A filtration membrane device 11, a water supply line L1 for supplying supply water to the filtration membrane device 11, a chemical injection device 5 for injecting a chemical for removing chlorine into the supply water flowing through the water supply line L1, and a medicine A control device 100 of the water treatment system 1 comprising a chlorine concentration measuring device 6 for measuring the chlorine concentration of the feed water between the pouring device 5 and the filtration membrane device 11, and the chlorine measured by the chlorine concentration measuring device 6 When the number of times the concentration exceeds the first threshold in a spiked manner, and when the number of times measured by the number measuring unit 101 within a predetermined time exceeds the first set number of times, the water treatment system An abnormality determination unit 102 for determining one abnormality.
[Selection] Figure 3

Description

  The present invention relates to a control device for a water treatment system including a filtration membrane device.

  In cleaning processes of food factories, machine factories, chemical factories, etc., high-purity pure water containing no impurities is used. In order to produce this kind of pure water, by using a filtration membrane such as a reverse osmosis membrane (hereinafter also referred to as “RO membrane”) in the water treatment system, salt water, heavy metal ions, dissolved silica, nitric acid are supplied from the supplied water. Nitrogen, bacteria, mutagenic substances, organochlorine compounds, etc. can be removed.

  In such a water treatment system, when supplying the supply water to the filtration membrane, the supply water is pretreated using a chlorine-based disinfectant, and residual chlorine is removed using chemicals such as SBS (sodium bisulfite). May be removed. In the removal of residual chlorine concentration by this chemical, there is a peculiar pattern of residual chlorine leakage.

  FIG. 5 shows the SBS chemical injection device 21, the residual chlorine meter 22 as a chlorine concentration measuring device, the RO device 23, and the storage tank 25, and the reducing agent chemical injection from the SBS chemical injection device 5. The leakage pattern of residual chlorine when removing residual chlorine remaining in raw water is shown. In the graph in FIG. 5, the amount of SBS input is indicated by a hump-like curve, and a spike-like leak of residual chlorine, that is, a relatively short one is indicated by a straight line having a spine-like protrusion. This is a leak pattern of duration.

  Since a diaphragm pump is normally used for the introduction of chemicals such as SBS, there is a pulsation in the amount of chemical solution input as shown in FIG. 5 (the degree of pulsation is the amount of chemical solution input and the water treatment system) Affected by construction). For this reason, if the amount of the chemical solution to be introduced is insufficient with respect to the residual chlorine concentration to be removed, the timing at which the residual chlorine concentration increases due to pulsation occurs at predetermined intervals in a spike shape. In addition, when the spike-like residual chlorine leak at the monitoring point is small, the supply water is stirred in the circulation line of the RO device 23, so that the residual chlorine concentration on the RO membrane surface becomes zero. When the input amount is insufficient and the spike-like residual chlorine leakage exceeds a certain level, residual chlorine remains even if agitated, which causes deterioration of the RO membrane.

  FIG. 6 is a graph showing how the residual chlorine concentration on the RO membrane surface and the peak value of spike-like residual chlorine leakage change as the amount of SBS input increases. The residual chlorine concentration on the RO membrane surface shows two patterns, a pattern (A) and a pattern (B).

  In the region where SBS is completely insufficient, the peak value of spike-like residual chlorine leakage and the residual chlorine concentration on the RO membrane surface both show high values, but both values increase as the amount of SBS input increases. Decrease. Eventually, the decreasing rate of the residual chlorine concentration on the RO membrane surface becomes slower as in the pattern (A), or the residual chlorine on the RO membrane surface becomes zero as in the pattern (B), and the SBS becomes Although it is not completely lacking, it is a region where spike-like residual chlorine leakage occurs.

  In the conventional monitoring method, the residual chlorine concentration is monitored in the SBS completely insufficient region. Even with this method, it is possible to monitor the residual chlorine concentration on the RO membrane surface, but when the residual chlorine concentration is found to be higher than the predetermined value, the RO membrane has already been damaged by chlorine degradation. It was often too late.

  Filtration membranes including RO membranes deteriorate in proportion to the product of exposure concentration of residual chlorine and exposure time. Therefore, the deterioration of the filtration membrane proceeds by being repeated even with low concentration and short-term residual chlorine leakage. More specifically, when the level of leakage of spike-like residual chlorine at the monitoring point is small, the residual chlorine on the filtration membrane surface can be obtained by stirring the feed water in the circulation line of the filtration membrane device. Although the concentration becomes zero, if the spike-like leakage exceeds a certain limit, residual chlorine remains even if the feed water is stirred in the circulation line, which causes deterioration of the filtration membrane. From the viewpoint of filter membrane protection, it is desirable to monitor using an alarm even for low-concentration and short-term residual chlorine leaks. However, if judgment conditions are strict, erroneous judgments due to disturbance factors occur frequently and are not practical.

  In other words, by monitoring this residual chlorine spike-like leak, before the filter membrane is damaged by chlorine deterioration, it detects a chlorine leak due to a malfunction of the chemical injection pump or an increase in residual water residual chlorine concentration. It becomes possible.

  In this regard, Patent Document 1 is different from the residual chlorine concentration, but when the ORP (oxidation-reduction potential) and ORP integrated values of the feed water measured by the measuring means are each equal to or higher than the reference value, the film deterioration is not observed. Since there is fear, the operation control apparatus of the desalination plant which has the ORP diagnostic means which operates an abnormality notification means is disclosed.

JP-A-8-126882

  As described above, it can be said that detecting a spike-like residual chlorine leak is beneficial to the monitoring target system, but there remains a problem regarding a specific monitoring method. Hereinafter, this problem will be described in detail with reference to FIGS. 7 and 8.

  As shown in FIG. 7, a leak that continues for a certain amount of time can be monitored by alarm monitoring of a threshold value × time, but a spike-like leak is difficult to distinguish from a false detection and is difficult to monitor with an alarm. .

  FIG. 8 is a graph showing alarm determination timing in the conventional monitoring method. Immediately after the start of water supply, the water quality becomes unstable due to factors such as the discharge of stagnant water. Therefore, the water quality is not monitored for a certain time T1 from the start of water supply. Thereafter, an alarm determination is made when the delay time T2 has elapsed since the residual chlorine concentration exceeded the threshold value. As described above, in normal monitoring of residual chlorine concentration, it is common to perform alarm determination when the residual chlorine concentration continuously exceeds a threshold value.

  However, spike-like residual chlorine leaks occur intermittently, and the concentration changes drastically, making it difficult to monitor spike-like leaks with the conventional detection and determination methods.

  Spike-like residual chlorine leakage occurs in synchronization with the shot of the chemical injection pump. The number of shots is usually 300 spm (5 Hz in terms of frequency) for a pump that is normally selected, and 360 spm (6 Hz in terms of frequency) depending on the type of pump. As shown in FIG. 9, the leakage interval is about 200 msec at the minimum. When calculating the integrated value of the residual chlorine concentration for use in alarming, for example, it is necessary to sample the concentration value that fluctuates at a cycle of 200 msec at a timing sufficiently finer than the fluctuating cycle, and to calculate the integration. An arithmetic circuit capable of accurately integrating these intervals is required. If the integration at 20 msec, which is 10 times the cycle, is used, a dedicated microcomputer circuit or a sequencer capable of high-speed processing to some extent is required, and the control panel itself becomes expensive.

  In addition, the electrode-type water quality meter cannot respond very quickly including the replacement rate of the sample water in the cell holder, and the ability to accurately output the true value against spike-like residual chlorine leakage is not possible. I can't expect it. For this reason, if the spike-like leakage pattern is integrated only by numerical processing, a large error occurs in the integrated value as shown in FIG.

  Therefore, an object of the present invention is to accurately monitor chlorine leakage to the filtration membrane device with a relatively simple circuit.

  The present invention relates to a filtration membrane device, a water supply line for supplying supply water to the filtration membrane device, a chemical injection device for injecting a chemical for removing chlorine from the supply water flowing through the water supply line, and the chemical injection device A control device of a water treatment system comprising a chlorine concentration measuring device for measuring the chlorine concentration of the supplied water between the filter membrane device and the filtration membrane device, wherein the chlorine concentration measured by the chlorine concentration measuring device is the first A frequency measurement unit that measures the number of times that the threshold value has been spiked, and an abnormality in the water treatment system is determined when the frequency measured by the frequency measurement unit within a predetermined time exceeds a first set number of times. And an abnormality determination unit.

  The medicine injection device controller further controls the medicine injection device, and the medicine injection device controller when the abnormality determination unit determines an abnormality because the number of times exceeds the first set number of times. It is preferable to control the medicine injection device so as to increase the amount of medicine injected by the medicine injection device.

  The medicine injection device controller further controls the medicine injection device, and the medicine injection device controller when the abnormality determination unit determines an abnormality because the number of times exceeds the first set number of times. Preferably, the drug injection device is controlled so as to increase the number of times the drug injection device injects a predetermined amount of medicine within a predetermined time.

  In addition, the abnormality determination unit determines an abnormality when the number of times is less than a second set number less than the first set number, and the number is lower than the second set number. Therefore, when the abnormality determination unit determines an abnormality, it is preferable that the drug injection device control unit controls the drug injection device so as to reduce the amount of the medicine injected by the drug injection device.

  In addition, the abnormality determination unit determines an abnormality when the number of times is less than a second set number less than the first set number, and the number is lower than the second set number. Therefore, when the abnormality determination unit determines an abnormality, the drug injection device control unit controls the drug injection device to reduce the number of times the drug injection device injects a predetermined amount of drug within a predetermined time. It is preferable to control.

  Moreover, it is preferable to further provide an alarm unit that issues an alarm when the number of times exceeds a third set number of times that is greater than the first set number of times.

  Moreover, it is preferable that the said frequency | count measurement part stops the measurement of the said frequency | count for the predetermined time from the start of water supply of the supply water to the said water treatment system, and / or the operating condition change of the said water treatment system.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the control apparatus which monitors the chlorine leak to a filtration membrane apparatus accurately with a comparatively simple circuit.

It is a whole water treatment system lineblock diagram provided with a control device concerning an embodiment of the present invention. It is a functional block diagram of a control device concerning an embodiment of the present invention. It is a figure which shows the outline | summary of this invention. It is a figure which shows the operation | movement flow of the control apparatus which concerns on embodiment of this invention. It is explanatory drawing about the problem of a prior art. It is explanatory drawing about the problem of a prior art. It is explanatory drawing about the problem of a prior art. It is explanatory drawing about the problem of a prior art. It is explanatory drawing about the problem of a prior art. It is explanatory drawing about the problem of a prior art.

[Configuration of the Invention]
First, with reference to FIG.1 and FIG.2, the whole structure of a water treatment system provided with the control apparatus which concerns on this invention is demonstrated.

  FIG. 1 is an overall configuration diagram of a water treatment system 1 including a control device 100 according to the present invention.

  As shown in FIG. 1, a water treatment system 1 includes a chemical injection device 5, a chlorine concentration measuring device 6, a pressurizing pump 8, an inverter 9, an RO module 11 as a filtration membrane device, and a constant flow valve 12. And a drain valve 17, a flow rate sensor FM, and a control device 100. Note that illustration of electrical connection lines between the control device 100 and the controlled device is omitted.

  The water treatment system 1 includes a supply water line L1, a permeate water line L2, a concentrated water line L3, a circulating water line L4, and a concentrated drainage line L5 as lines. “Line” is a general term for lines capable of flowing fluid such as flow paths, paths, and pipelines. Moreover, the water which distribute | circulates the supply water line L1, the concentrated water line L3, or the circulating water line L4 irrespective of the origin (source) and the water quality is also called "supply water", the concentrated water line L3, the circulating water line L4. Or the water which distribute | circulates the concentration drainage line L5 is also called "concentrated water."

  The supply water line L <b> 1 is a line that supplies the supply water W <b> 11 to W <b> 12 toward the RO module 11. The feed water line L1 includes a first feed water line L11 and a second feed water line L12 from the upstream side toward the downstream side.

  The upstream end of the first supply water line L11 is connected to the water source 2 of the supply water W11. The downstream end of the first supply water line L11 is connected to the second supply water line L12 and the circulating water line L4 at the connection portion J1. In the first supply water line L11, the chemical injection device 5 and the chlorine concentration measuring device are provided in this order from the upstream side to the downstream side.

  The chemical injection device 5 is a device that injects a reducing agent into a line through which one or more of the supply water among the supply water line L1, the concentrated water line L3, and the circulating water line L4 flows. In the present embodiment, the chemical injection device 5 is a device that injects a reducing agent into the supply water W11 that flows through the supply water line L1 (first supply water line L11). The chemical injection device 5 is electrically connected to the control device 100.

  In the present embodiment, the chemical injection device 5 intermittently injects a reducing agent in order to remove residual chlorine from the supply water W11. In addition, as an example of a reducing agent, SBS etc. are mentioned, for example.

  The chlorine concentration measuring device 6 measures the concentration of residual chlorine remaining in the supply water W11 flowing through the supply water line L1. The chlorine concentration measuring device 6 is electrically connected to the control device 100, and the measured residual chlorine concentration is transmitted to the control device 100.

  The upstream end portion of the second supply water line L12 is connected to the connection portion J1. The downstream end of the second supply water line L12 is connected to the primary inlet port of the RO module 11. A pressurizing pump 8 is provided in the second supply water line L12.

  The pressurizing pump 8 is a device that sucks in the supply water W12 and pumps (discharges) it toward the RO module 11. The driving power whose frequency is converted is supplied from the inverter 9 to the pressurizing pump 8. The pressurizing pump 8 is driven at a rotational speed corresponding to the frequency (hereinafter also referred to as “driving frequency”) of the driving power supplied (input).

  The inverter 9 is an electric circuit (or a device having the circuit) that supplies driving power whose frequency is converted to the pressure pump 8. The inverter 9 is electrically connected to the control device 100. A command signal is input from the control device 100 to the inverter 9. The inverter 9 outputs driving power having a driving frequency corresponding to the command signal (current value signal or voltage value signal) input by the control device 100 to the pressurizing pump 8.

  The supply water W12 is supplied to the RO module 11 via the pressurizing pump 8. The supply water W12 includes a supply water W11 and a circulating water W40 (described later).

  The RO module 11 is a facility that separates the supply water W12 into permeate water W20 and concentrated water W30. Specifically, the RO module 11 is a facility that performs membrane separation processing on the supply water W12 discharged from the pressurizing pump 8 into permeated water W20 from which dissolved salts have been removed and concentrated water W30 from which dissolved salts have been concentrated. is there. The RO module 11 includes a single or a plurality of reverse osmosis membrane elements (not shown). The RO module 11 membrane-separates the supply water W12 with these reverse osmosis membrane elements to produce permeated water W20 and concentrated water W30.

  The permeated water line L2 is a line for sending the permeated water W20 separated by the RO module 11. The upstream end of the permeate line L <b> 2 is connected to the secondary port of the RO module 11. The downstream end of the permeate line L2 is connected to a storage tank (not shown). A flow rate sensor FM is provided in the permeated water line L2.

  The flow rate sensor FM is a device that detects the flow rate of the permeated water W20 flowing through the permeated water line L2. The flow sensor FM is electrically connected to the control device 100. The flow rate of the permeated water W20 detected by the flow rate sensor FM (hereinafter also referred to as “detected flow rate value”) is transmitted to the control device 100 as a pulse signal.

  The concentrated water line L3 is a line through which the concentrated water W30 separated by the RO module 11 flows. The upstream end of the concentrated water line L3 is connected to the primary outlet port of the RO module 11. Further, the downstream side of the concentrated water line L3 branches to the circulating water line L4 and the concentrated drainage line L5 at the connection portion J2.

  The circulating water line L4 is connected to the concentrated water line L3, and is a line that returns concentrated water (circulated water W40) as supply water to the supply water line L1. In the present embodiment, the circulating water line L4 uses the concentrated water W30 flowing through the concentrated water line L3 as the circulating water W40, upstream of the pressurizing pump 8 in the supply water line L1, and more than the chlorine concentration measuring device 6. This line is returned (circulated) to the downstream side. The upstream end of the circulating water line L4 is connected to the concentrated water line L3 at the connecting portion J2. Further, the downstream end of the circulating water line L4 is connected to the supply water line L1 at the connecting portion J1. A constant flow valve 12 is provided in the circulating water line L4.

  The constant flow valve 12 adjusts the flow rate of the circulating water W40 flowing through the circulating water line L4 so as to maintain a predetermined constant flow rate value. The “constant flow value” held in the constant flow valve 12 is a concept having a range of constant flow values, and is not limited to the target flow value in the constant flow valve 12. For example, in consideration of the characteristics of the constant flow mechanism (for example, temperature characteristics caused by the material and structure), the constant flow mechanism 12 includes those having an adjustment error of about ± 10% with respect to the target flow rate value. The constant flow valve 12 retains a constant flow value without requiring auxiliary power or external operation, and includes, for example, what is called by the name of a water governor. The constant flow valve 12 may be operated by auxiliary power or external operation to hold a constant flow value.

  The concentrated drainage line L5 is connected to the concentrated water line L3 and is a line for discharging concentrated water as the concentrated drainage W50 out of the system. In the present embodiment, the concentrated drainage line L5 is connected to the concentrated water line L3 at the connection portion J2, and is a line for discharging the concentrated water W30 separated by the RO module 11 to the outside of the apparatus (outside the system) as the concentrated drainage W50. It is.

  The drainage valve 17 is a valve that adjusts the flow rate of the concentrated drainage W50 discharged from the apparatus from the concentrated drainage line L5. The drain valve 17 is electrically connected to the control device 100. The valve opening degree of the drain valve 17 is controlled by a drive signal transmitted from the control device 100. The drainage flow rate of the concentrated drainage W50 can be adjusted by transmitting a current value signal (for example, 4 to 20 mA) from the control device 100 to the drainage valve 17 and controlling the valve opening degree.

  The control device 100 includes a CPU, a ROM, a RAM, a CMOS memory, and the like, which are known to those skilled in the art and configured to be able to communicate with each other via a bus.

  The CPU is a processor that controls the water treatment system 1 as a whole. The CPU reads out various programs stored in the ROM via the bus, and controls the entire water treatment system 1 according to the various programs, so that the control device 100 performs a number of times as shown in the functional block diagram of FIG. The measurement unit 101, the abnormality determination unit 102, the medicine injection device control unit 103, and the alarm unit 104 are configured to be realized. Various data such as temporary calculation data and display data are stored in the RAM. The CMOS memory is configured as a non-volatile memory that is backed up by a battery (not shown) and that retains the memory state even when the water treatment system 1 is powered off.

  The frequency measuring unit 101 measures the number of times that the chlorine concentration measured by the chlorine concentration measuring device 6 exceeds a predetermined threshold value in a spike manner in a predetermined period. Specifically, as shown in FIG. 3, during the operation of the RO module 11, the number of times that the chlorine concentration measured by the chlorine concentration measuring device 6 exceeds the threshold value in a spike shape, that is, shorter than a predetermined time. Count the number of times that the threshold is exceeded in time. It should be noted that the water quality becomes unstable due to factors such as discharge of stagnant water for a predetermined time from the start of water supply to the water treatment system 1 and / or the change of the operation conditions of the water treatment system 1, and normal operation Even if it is made, residual chlorine leakage may occur. For this reason, the number counting unit 101 does not have to count the number of times that the threshold value has been exceeded in a spike manner during the predetermined time.

  The abnormality determination part 102 compares the frequency | count which the frequency | count measurement part 101 measured with the preset frequency | count set beforehand, and determines the abnormality of the water treatment system 1 based on the said comparison result. More specifically, the abnormality determination unit 102 determines the abnormality of the water treatment system 1 when the number of times measured by the number measurement unit 101 exceeds the first set number of times. On the other hand, also when the frequency | count which the frequency | count measurement part 101 measured is still lower than the 2nd setting frequency which is lower than a 1st setting frequency, abnormality of the water treatment system 1 is determined.

The chemical injection device control unit 103 controls the chemical injection device 5 to increase or decrease the amount of reducing agent injected by the chemical injection device 5.
More specifically, when the number of times measured by the abnormality determination unit 102 exceeds the first set number of times, the number of times that the medicine injection device 5 injects the medicine into the supply water W11 is a predetermined number of times. The medicine injection device control unit 103 controls the medicine injection device 5 so as to increase the amount of the medicine to be injected. Alternatively, the drug injection device control unit 103 may control the drug injection device 5 so that the number of times that the drug injection device 5 injects a predetermined amount of drug into the supply water W11 is increased.
On the other hand, when the number of times measured by the abnormality determination unit 102 is less than the second set number of times, the medicine injection device 5 injects the medicine into the supply water W11 while keeping the predetermined number of times. The chemical injection device control unit 103 controls the chemical injection device 5 so as to reduce the amount of the chemical. Alternatively, the medicinal device controller 103 may control the medicinal device 5 so as to reduce the number of times that the medicinal device 5 injects a predetermined amount of medicine into the supply water W11.

  The alarm unit 104 issues an alarm when the number of times measured by the number measuring unit 101 exceeds a third set number of times that is higher than the first set number of times.

  Next, the operation of the control device 100 according to the embodiment of the present invention will be described with reference to the flowchart of FIG. FIG. 4 is a flowchart showing an operation example of the control device 100 according to the embodiment of the present invention. Although the above is repeated, in the following description, the relationship between the first set number, the second set number, and the third set number is “second set number <first set number <first number. 3 setting times ”.

  In step S <b> 1, the number counting unit 101 measures the number of times that the residual chlorine concentration of the supply water W <b> 11 exceeds the first threshold value in a spiked manner during a predetermined period.

  In step S2, when the number of measurements is equal to or less than the first set number (S2: YES), the process proceeds to step S3. If the number of measurements exceeds the first set number (S2: NO), the process proceeds to step S4.

  In step S3, when the number of measurements is equal to or greater than the second set number (S3: YES), the process returns to step S1 (return). If the number of measurements is less than the second set number (S3: NO), the process proceeds to step S5.

  In step S4, when the number of measurements is equal to or less than the third set number (S4: YES), the process proceeds to step S6. When the number of measurements exceeds the third set number (S4: NO), the process proceeds to step S7.

  In step S5, the chemical injection device control unit 103 controls the chemical injection device 5 so as to reduce the amount of the chemical to be injected while the number of times that the chemical injection device 5 injects the medicine into the supply water W11 is a predetermined number. . Alternatively, the medicinal device controller 103 may control the medicinal device 5 so as to reduce the number of times that the medicinal device 5 injects a predetermined amount of medicine into the supply water W11. Thereafter, the process returns to step S1 (return).

  In step S <b> 6, the chemical injection device control unit 103 controls the chemical injection device 5 so as to increase the amount of the chemical to be injected while the number of times that the chemical injection device 5 injects the medicine into the supply water W <b> 11 is a predetermined number. . Alternatively, the drug injection device control unit 103 may control the drug injection device 5 so that the number of times that the drug injection device 5 injects a predetermined amount of drug into the supply water W11 is increased. Thereafter, the process returns to step S1 (return).

  In step S7 as well, similarly to step S6, the medicinal device control unit 103 controls the medicinal device 5 so as to increase the amount of the medicine injected into the supply water W11 by the medicinal device 5. Alternatively, the drug injection device control unit 103 may control the drug injection device 5 so that the number of times that the drug injection device 5 injects a predetermined amount of drug into the supply water W11 is increased.

  In step S8, the warning unit 104 issues an alarm. Thereafter, the process returns to step S1 (return).

[Effect of the embodiment]
According to the control device 100 described above, for example, the following effects are exhibited.
In the control device 100 of the present invention, the number measuring unit 101 that measures the number of times that the chlorine concentration measured by the chlorine concentration measuring device 6 exceeds the first threshold value in a spike shape, and the number measuring unit 101 measured within a predetermined time. An abnormality determination unit 102 that determines an abnormality of the water treatment system 1 when the number of times exceeds the first set number of times.

  Therefore, instead of calculating the integrated value when the chlorine concentration exceeds the threshold value, the chlorine leak to the filtration membrane device is reliably monitored more easily than the normal integration method by measuring the number of times the threshold value is exceeded. be able to.

  In addition, when the abnormality determination unit 102 determines an abnormality because the number of times measured by the number measurement unit 101 exceeds the first set number of times, the drug injection device control unit 103 determines the amount of drug injected by the drug injection device 5. The chemical injection device 5 is controlled so as to increase.

  Therefore, when the amount of residual chlorine in the supply water W11 to the RO module 11 is large, it is possible to protect the RO membrane by increasing the amount of medicine injected by the chemical injection device 5 and reducing the amount of residual chlorine. Become.

  In addition, when the abnormality determination unit 102 determines abnormality because the number of times measured by the number measurement unit 101 exceeds the first set number of times, the drug injection device control unit 103 determines that the drug injection device 5 is located within a predetermined time. The medicine injection device 5 is controlled so as to increase the number of times of injecting a fixed amount of medicine.

  Therefore, when the residual chlorine in the supply water W11 to the RO module 11 is large, the number of times that the chemical injection device 5 injects a predetermined amount of medicine is increased, and the amount of residual chlorine is reduced, thereby protecting the RO membrane. Is possible.

  In addition, since the number of times measured by the number counting unit 101 is lower than the second set number of times, when the abnormality determination unit 102 determines abnormality, the drug injection device control unit 103 determines the medicine to be injected by the drug injection device 5. The chemical injection device 5 is controlled so as to reduce the amount.

  Moreover, since the frequency | count of measurement by the frequency | count measurement part 101 is lower than the 2nd setting frequency | count, when the abnormality determination part 102 determines abnormality, the chemical injection apparatus control part 103 is the chemical injection apparatus 5 within predetermined time. The medicine injection device 5 is controlled so as to reduce the number of times of injecting a predetermined amount of medicine.

  Therefore, when the medicine is excessively injected into the supply water W11 supplied to the RO module 11, the injection amount of the medicine can be reduced.

  Further, when the number of times measured by the number measuring unit 101 exceeds the third set number of times larger than the first set number of times, the alarm unit 104 issues an alarm.

  Therefore, when the residual chlorine in the supply water W11 to the RO module 11 is considerably large, by issuing an alarm to the administrator of the water treatment system 1, there is a possibility that the chemical injection pump is malfunctioning or the chemical solution is deteriorated. Can inform about.

  In addition, the frequency measurement unit 101 stops the measurement of the frequency for a predetermined time from the start of water supply to the water treatment system 1 and / or the change of the operation condition of the water treatment system 1.

  During the predetermined time after the start of operation of the water treatment system 1 and / or the change of operation conditions, the chemical injection is unstable, and even if it can be operated normally, residual chlorine leakage may occur. is there. By masking this period, it becomes possible to monitor leakage of residual chlorine only during steady operation.

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

  For example, in the above embodiment, the embodiment using the RO module 11 as the supply water filtering device in the water treatment system 1 has been described, but the present invention is not limited to this. For example, the control device 100 is applied to a water treatment system including a filtration device using a membrane other than the RO membrane, such as a UF membrane, or a filtration device using a filter medium such as an ion exchange resin. It is also possible to do.

DESCRIPTION OF SYMBOLS 1 Water treatment system 2 Water source 5 Chemical injection device 6 Chlorine concentration measuring device 8 Pressure pump 9 Inverter 11 RO module 12 Constant flow valve 17 Drain valve 20 Water treatment system 21 SBS chemical injection device 22 Residual chlorine meter 23 RO device 25 Storage tank DESCRIPTION OF SYMBOLS 100 Control apparatus 101 Counting part 102 Abnormality determination part 103 Chemical injection apparatus control part 104 Alarm part

Claims (7)

A filtration membrane device, a water supply line for supplying supply water to the filtration membrane device, a chemical injection device for injecting a chemical for removing chlorine from the supply water flowing through the water supply line, the chemical injection device, and the filtration membrane A control device of a water treatment system comprising a chlorine concentration measuring device for measuring the chlorine concentration of the supplied water with the device,
A frequency measurement unit that measures the number of times that the chlorine concentration measured by the chlorine concentration measurement device exceeds the first threshold in a spiked manner;
An abnormality determination unit that determines an abnormality of the water treatment system when the number of times measured by the number-of-times counting unit within a predetermined time exceeds a first set number of times;
A control device comprising: A drug injection device controller for controlling the drug injection device;
When the abnormality determination unit determines an abnormality because the number of times exceeds the first set number of times, the drug injection device control unit increases the amount of drug injected by the drug injection device. The control apparatus of Claim 1 which controls a chemical injection apparatus. A drug injection device controller for controlling the drug injection device;
When the abnormality determination unit determines abnormality because the number of times exceeds the first set number of times, the drug injection device control unit injects a predetermined amount of drug within a predetermined time. The control device according to claim 1, wherein the medicine injection device is controlled to increase the number of times. The abnormality determination unit determines an abnormality when the number of times is less than a second set number of times less than the first set number of times,
Since the number of times is lower than the second set number of times, when the abnormality determination unit determines an abnormality, the drug injection device control unit decreases the amount of the drug injected by the drug injection device. The control apparatus of Claim 2 or 3 which controls the said chemical injection apparatus. The abnormality determination unit determines an abnormality when the number of times is less than a second set number of times less than the first set number of times,
Since the number of times is lower than the second set number of times, when the abnormality determination unit determines an abnormality, the drug injection device control unit injects a predetermined amount of the drug within a predetermined time. The control device according to claim 2, wherein the medicine injection device is controlled so as to reduce the number of times to perform.   The control device according to any one of claims 1 to 5, further comprising an alarm unit that issues an alarm when the number of times exceeds a third set number of times that is greater than the first set number of times. . The said frequency | count measurement part stops the measurement of the said frequency | count for the predetermined time from the supply water supply start to the said water treatment system, and / or the operating condition change of the said water treatment system. The control device according to item 1.

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