JP2018099643A - Filtering device and method for controlling filtering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filtering device that can perform proper reverse washing operation even when water temperature varies, and to provide a method for controlling a filtering device.SOLUTION: A filtering device 1 includes: a filtering tank 31 storing a filter medium for filtering water passing from a primary side to a secondary side; a drain pipe 34 connected on a primary side of the filtering tank 31; and a reverse washing pump 14 having a plurality of pumps 61 for supplying water that is filtered by the filtering tank 31 to the secondary side of the filtering tank 31.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a filtration device capable of backwashing and a method for controlling the filtration device.

  At present, there is known a technique of using raw water such as well water by increasing the pressure with a pump to use it as domestic water for household use or industrial water for a factory. However, in raw water, for example, iron and manganese are dissolved as impurities. For this reason, in order to use it as domestic water or industrial water, a filtration device capable of removing iron and manganese by removing raw water by filtering the raw water with a filter medium is known (for example, see Patent Document 1). ).

  In such a filtration device capable of removing iron and manganese, the filter medium is provided in a cylindrical filter tank, and the raw water into which the chemical solution is injected passes through the filter medium, so that the iron and manganese in the raw water are supplied. Remove. Further, the filtration device periodically performs a so-called backwash operation in which impurities adhered to the filter material are removed by filtering a certain amount of water and then backwashing, thereby extending the life of the filter material.

  When the filtering device is backwashed by the filtering device, the filtering material is lifted by the flow of water in the filtering tank, and impurities attached to the filtering material are removed. The removal amount of impurities attached to the filter medium varies depending on the backwashing expansion rate, which is the degree of lifting of the filter medium. For this reason, the filtering device is required to perform backwashing at a flow rate at which a reverse development rate that can appropriately remove impurities is obtained.

JP 2003-269630 A

  The above-described filtration device has the following problems. That is, even if the flow rate at which an appropriate backwashing rate is obtained at a certain water temperature is set in the filtration device, if the water temperature changes due to seasonal changes, the backwashing rate changes at the same flow rate, and an appropriate backwashing rate is obtained. May not be performed. Specifically, when the water temperature is high, a larger flow rate is required to obtain the same reverse development rate as compared with the case where the water temperature is low. For this reason, the flow rate at the time of the backwash operation set in the filtration device is set to a flow rate at which a desired backwash development rate is required even when the water temperature is high.

  However, when the water temperature is lowered, if the backwashing is performed at a flow rate set at a high water temperature, the filter medium may be developed excessively and the filter medium may flow out to the primary side. For example, the filter tank may have a structure or size that can prevent the filtering material from flowing out to the primary side, but there is a problem that a large design change is required.

  Then, an object of this invention is to provide the control method of the filtration apparatus and filtration apparatus which can perform a suitable backwash operation even if water temperature changes.

  As one aspect of the present invention, the filtration device filters the water passing from the primary side to the secondary side, the filtration tank containing the filtering material, the drain pipe connected to the primary side of the filtration tank, and A backwash pump having a plurality of pumps for supplying the water filtered in the filtration tank to the secondary side of the filtration tank.

  As one aspect of the present invention, a method for controlling a filtration device includes a method of filtering water passing from a primary side to a secondary side, treating a plurality of water treated in a filtration tank containing a filtering material and stored in a storage tank. From the secondary side of the filtration tank to the primary side of the filtration tank, the water temperature of the water stored in the storage tank and the backwash pump At least one of the water temperature of the water supplied to the filtration tank is detected by a temperature sensor, and the water temperature detected by the temperature sensor and the backwashing expansion rate of the filter medium stored as a threshold value in the storage unit are predetermined. When the water temperature detected by the temperature sensor exceeds the threshold, the control unit increases the number of driven pumps.

  ADVANTAGE OF THE INVENTION According to this invention, even if water temperature changes, the filtration apparatus and the control method of a filtration apparatus which can perform a suitable backwash operation can be provided.

Explanatory drawing which shows the structure of the filtration apparatus which concerns on one Embodiment of this invention. The flowchart which shows an example of the control method of the backwash operation using the filtration apparatus.

Hereinafter, the filtration apparatus 1 which concerns on the 1st Embodiment of this invention is demonstrated using FIG.1 and FIG.2.
FIG. 1 is an explanatory diagram showing a configuration of a filtration device 1 according to the first embodiment of the present invention, and FIG. 2 is a flowchart showing an example of a control method of a backwash operation using the filtration device 1.

  As shown in FIG. 1, the filtration device 1 includes a pump device 11 provided in the raw water supply source 100, a filtration unit 12 provided on the secondary side of the pump device 11, and a secondary side of the filtration unit 12. The storage tank 13 provided, the backwash pump 14, the chemical | medical solution injection device 15, and the control panel 16 are provided.

  For example, the filtration device 1 injects a chemical solution into the raw water by the chemical solution injection device 15 and removes iron and manganese contained in the raw water by the filtration unit 12 and can remove solids such as sand existing in the raw water. Is formed. Here, the supply source 100 is, for example, a well.

  The pump device 11 is a land pump capable of pumping well water, for example. The pump device 11 includes a pump 21, a motor 22 that drives the pump 21, and a pipe 23 connected to the secondary side of the pump 21. The pump 21 is connected to the filtration unit 12 via a pipe 23. The motor 22 is connected to the control panel 16 via a signal line 99. The pipe 23 connects the pump 21 and the filtration unit 12.

  The filtration unit 12 includes a filtration tank 31, a suction pipe 32, a first three-way valve 33, a drain pipe 34, a discharge pipe 35, a second three-way valve 36, a water supply pipe 37, a backwash pipe 38, And a temperature sensor 39.

  The filter tank 31 includes a plurality of filter media stacked inside. One of the plurality of filter media is configured to be able to remove iron from raw water into which a chemical solution has been injected. One of the plurality of filter media is configured to be able to remove manganese from raw water into which a chemical solution has been injected. One of the plurality of filter media is configured to be able to remove solids contained in the raw water.

  The suction pipe 32 is connected to the filtration tank 31. One end of the suction pipe 32 is disposed above the uppermost layer of the plurality of filter media.

  The first three-way valve 33 is an electric valve and is connected to the control panel 16 via a signal line 99. The first three-way valve 33 has three ports, and connects any two of these ports by switching the internal flow path. The first three-way valve 33 has a first port connected to the pipe 23. The first three-way valve 33 has a second port connected to the other end of the suction pipe 32. The first three-way valve 33 has a third port connected to the drain pipe 34.

  The drain pipe 34 includes a flow rate adjustment valve 34a. The drain pipe 34 is connected to a drain destination 110 such as a drain. The flow rate adjustment valve 34 a is configured to be able to adjust the flow rate of the drain pipe 34. The flow rate adjusting valve 34a sets the drainage pipe 34 to a flow rate at which a predetermined backwash development rate is obtained by the flow rate of the drainage pipe 34 when backwashing is performed and the water temperature is low in winter or the like.

  Here, the reverse tip development rate is a development rate of the filter medium in the filtration tank 31 during the backwash operation. Specifically, the backwashing expansion rate is a condition in which the filtering material stacked in the filtering tank 31 floats in the filtering tank 31 due to the flow of water in the backwashing operation from the discharge pipe 35 to the suction pipe 32. This affects the amount of impurities removed from the excess material. Moreover, the backwashing development rate changes depending on the water temperature, and decreases as the water temperature increases. For this reason, the reverse expansion | deployment rate which can remove suitably the impurity adhering to a filter medium suitably is set for the filtration apparatus 1 with a shape, a performance, the kind of filter medium, etc.

  The discharge pipe 35 is connected to the filtration tank 31. One end of the discharge pipe 35 is disposed in the lowermost layer of the plurality of filter media.

  The second three-way valve 36 is an electric valve and is connected to the control panel 16 via a signal line 99. The second three-way valve 36 has three ports, and connects any two of these ports by switching the internal flow path. The second port of the second three-way valve 36 is connected to the other end of the discharge pipe 35. The second port of the second three-way valve 36 is connected to the water supply pipe 37. The second three-way valve 36 has a third port connected to the backwash pipe 38.

  The water supply pipe 37 is connected to the storage tank 13. The water supply pipe 37 constitutes a flow path for supplying water discharged from the discharge pipe 35 to the storage tank 13. The backwash pipe 38 is connected to the backwash pump 14.

  The temperature sensor 39 is configured to be able to detect the temperature of the water supplied to the filtration tank 31 by the backwash pump 14. The temperature sensor 39 is provided in at least one of the storage tank 13 and the backwash pipe 38. For example, the temperature sensor 39 is provided in one of the storage tank 13 and the backwash pipe 38. The temperature sensor 39 is configured to be able to detect the temperature of the water stored in the storage tank 13 and the temperature of the water flowing through the backwash pipe 38. The temperature sensor 39 is connected to the control panel 16 via the signal line 99 and is configured to be able to transmit the detected water temperature information to the control panel 16.

  The backwash pump 14 includes a plurality of pumps 61 and a plurality of motors 62. The backwash pump 14 includes a check valve 63 and an on-off valve 64 on the secondary side of the pump 61. In the present embodiment, the backwash pump 14 will be described with a configuration including two pumps 61. The motor 62 is connected to the control panel 16 via a signal line 99. The on-off valve 64 is configured to be manually openable and closable, for example.

  The chemical solution injector 15 is connected to the pipe 23 and configured to inject the chemical solution into the raw water flowing through the pipe 23. The chemical solution injector 15 includes, for example, a tank that stores the chemical solution and a diaphragm that supplies the chemical solution in the tank to the secondary side.

  The control panel 16 includes a storage unit 51 and a control unit 52.

  The storage unit 51 is configured to be able to store information detected by the temperature sensor 39. The storage unit 51 stores an arbitrarily set threshold and an arbitrarily set time.

  The threshold value is a value for selecting whether to determine whether or not to drive the stopped pump 61 based on the temperature detected by the temperature sensor 39 during backwashing. The threshold is set to a water temperature that requires the flow rate of the drain pipe 34 when all the pumps 61 are driven in order to obtain a predetermined reverse deployment rate during backwashing. For example, the threshold is set to 20 ° C.

  The set time is a time until it is determined that the water temperature is high when the water temperature during backwashing exceeds a threshold value for a predetermined time and the stopped pump 61 is driven, and is set appropriately.

  The controller 52 is configured to be able to switch between the first three-way valve 33 and the second three-way valve 36. The controller 52 is configured to drive the pump 21 by controlling the motor 22 of the pump device 11. The controller 52 is configured to drive the pump 61 by controlling the motor 62 of the backwash pump 14.

  The control unit 52 has the following functions (1) to (3).

  (1) Function to perform normal operation to filter raw water.

  (2) A function of performing a backwashing operation in which the water in the filtration tank 31 is made to flow backward to wash the inside of the filtration tank.

  (3) A function of controlling the flow rate based on the water temperature during the backwash operation.

The functions (1) to (3) of the control unit 52 will be described.
The function (1) is a function of performing a normal operation of removing impurities composed of iron, manganese and solid matter from the raw water by filtering the raw water into which the chemical solution has been injected in the filtration tank 31. Specifically, the control unit 52 can configure a flow path that is connected to the storage tank 13 through the pipe 23, the suction pipe 32, the filtration tank 31, the discharge pipe 35, and the water supply pipe 37 from the pump 21 of the pump device 11. Switches the first three-way valve 33 and the second three-way valve 36.

  In this state, the control unit 52 controls the motor 22 to drive the pump 21 to supply the raw water to the filtration tank 31 and to inject the chemical liquid into the raw water according to the flow rate, and the raw water into which the chemical liquid has been injected. Passes through the filtration tank 31. Thereby, while the said raw | natural water removes the iron and manganese which are contained in raw | natural water with the filter material in the filtration tank 31, the solid substance in raw | natural water is filtered. Thus, function (1) is a function of removing iron, removing manganese and filtering from raw water.

  Function (2) is to allow water to flow backward in the filtration tank 31 by flowing raw water from the discharge pipe 35 toward the suction pipe 32 in the filtration tank 31 after a predetermined time has elapsed in the filtration operation. This is a function of performing a backwashing operation in which the filter medium in the filter tank 31 is developed and the filter medium is washed. Specifically, the first three-way valve 33 and the second three-way valve 36 flow from the pump 61 of the backwash pump 14 to the backwash pipe 38, the discharge pipe 35, the filtration tank 31, the suction pipe 32, and the drain pipe 34 in this order. Switch.

  In this state, when the control unit 52 drives the motor 62 for a predetermined time, the water stored in the storage tank 13 flows back through the filtration tank 31 from the discharge pipe 35 and drains from the suction pipe 32. By passing through the pipe 34, the filter medium is washed, and the washed contaminated water is drained to the drain destination 110. Thereby, the impurities in the filtration tank 31 and the iron and manganese adhering to the filter medium are removed, and the inside of the filtration tank 31 is washed. Thus, the function (2) is a function of washing the inside of the filtration tank 31 by causing the raw water to flow backward and passing through the filtration tank 31. Note that the backwash operation is performed, for example, when the accumulated time of the normal operation has passed a predetermined time.

  The cumulative operation time that is a threshold value for switching from the normal operation to the backwash operation in the function (2) is that the integrated removal amount obtained from the operation time and the removal amount of iron and manganese set in the filtration tank 31 is a predetermined value. It is time to reach.

For example, when the iron content in the raw water is Fe = 5 mg / l, the manganese content in the raw water is 1 mg / l, and the total content is 6 mg / l, the total amount of iron and manganese removed from the raw water The cumulative operation time when the backwash operation is performed when the removal amount reaches 10 g will be described. In this case, when 1.67 m ³ of raw water is passed through, the total removal amount reaches 10 g, so the accumulated operation time corresponding to the total removal amount is stored in the storage unit 51 as a threshold value.

  Function (3) controls the flow rate of water discharged from the backwash pump 14 by controlling the backwash pump 14 based on the water temperature detected by the temperature sensor 39 during the backwash operation by the function (2). Thus, the flow rate of the water flowing through the filtration tank 31 is controlled to a flow rate at which the filter medium has an appropriate backwash development rate.

  Specifically, during the backwash operation in which the backwash pump 14 is driven by one pump 61, the water temperature in the storage tank 13 or the water temperature in the backwash pipe 38 detected by the temperature sensor 39 is detected by the control unit 52. It is determined whether or not the threshold stored in the storage unit 51 has been exceeded. When the detected water temperature exceeds the threshold value for a predetermined time, the stopped pump 61 is driven, and the number of pumps 61 to be driven is increased by one. Thereby, when water temperature is high, the flow volume of the water which the backwash pump 14 discharges is increased, and the flow velocity in the filtration tank 31 is increased. Thus, function (3) maintains the backwashing deployment rate of the filter medium at a deployment rate that allows a predetermined backwashing by changing the flow rate in the filtration tank 31 based on the water temperature during the backwashing operation. It is a function.

  Next, the control method at the time of backwashing operation of such a filtration apparatus 1 is demonstrated below using the flowchart shown in FIG.

  As shown in FIG. 2, first, the control unit 52 performs a filtering operation (step ST1). Next, when the cumulative operation time of the filtration operation elapses for a predetermined time (step ST2), the control unit 52 stops the pump device 11 and then drives the backwash pump 14 (step ST3). At this time, the control unit 52 first performs the independent operation of the backwash pump 14 by the single pump 61. Next, the control part 52 detects the water temperature at the time of backwashing with the temperature sensor 39 (step ST4).

  Next, the control unit 52 compares the detected water temperature with the threshold value stored in the storage unit 51 (step ST5). When the detected water temperature exceeds the threshold value (YES in step ST5), the control unit 52 determines whether or not a predetermined time has elapsed after the detected water temperature exceeds the threshold value (step ST6). When the time when the detected water temperature exceeds the threshold value has not passed the predetermined time (NO in step ST6), the process returns to step ST5. When the time when the detected water temperature exceeds the threshold value has passed a predetermined time (NO in step ST6), the control unit 52 drives the stopped pumps 61 and increases the number of pumps 61 to be driven ( Step ST7).

  Next, the control unit 52 determines whether or not a predetermined time has elapsed since the start of the backwash operation (step ST8). If the predetermined time has not elapsed since the start of the backwash operation (NO in step ST8), the process returns to step ST5 and the backwash operation is continued. When a predetermined time has elapsed from the start of the backwash operation (YES in step ST8), the control unit 52 stops the backwash pump 14, ends the backwash operation, drives the pump device 11, and performs the filtration operation. Perform (step ST9).

  In step ST5, when the detected water temperature is equal to or lower than the threshold value (NO in step ST5), the control unit 52 maintains the operation in the case of a single operation with one pump 61, and a plurality of pumps. In the case of the multiple unit operation by 61, one pump 61 to be driven is reduced (step ST10). Next, the control unit 52 continues the backwash operation until the predetermined time elapses in the backwash operation, and performs the filtration operation after the predetermined time has elapsed (YES in step ST8).

  According to the filtration device 1 configured as described above, when the water temperature is equal to or higher than a predetermined temperature during the backwash operation, the number of pumps 61 is increased and the flow rate of water discharged from the backwash pump 14 is increased. By controlling the above, even if the water temperature rises due to seasonal fluctuations or the like, the backwashing development rate of the filter medium in the filtration tank 31 can be set to a desired development rate.

  That is, when the water temperature rises and the reverse tip development rate during the backwash operation decreases, the number of pumps 61 driven by the backwash pump 14 is increased, so that the water flowing from the backwash pump 14 to the drainage destination 110 is increased. Therefore, the flow rate of the water flowing through the filtration tank 31 increases. Thereby, the filtration apparatus 1 can increase the expansion rate of the filtering material in the filtration tank 31.

  As described above, according to the filtration device 1 according to an embodiment of the present invention, an appropriate backwash operation can be performed even when the water temperature changes.

  The present invention is not limited to the above embodiment. For example, in the example mentioned above, although the filtration apparatus 1 demonstrated the structure which uses the two pumps 61 of the backwash pump 14, it is not limited to this. That is, a configuration in which three or more pumps 61 of the backwash pump 14 are provided may be employed. By setting it as such a structure, the filtration apparatus memorize | stores several threshold value in the memory | storage part 51, and whenever the water temperature detected by the temperature sensor 39 exceeds several threshold value sequentially, it increases the pump 61 to drive sequentially. What is necessary is just composition.

  Moreover, in the example mentioned above, although the filtration apparatus 1 demonstrated the structure provided with the storage tank 13 as a process water tank which stores the filtered water, it is not limited to this, It is good also as a structure which does not have the storage tank 13. FIG. . When the filtration device 1 does not have the storage tank 13, the filtration device 1 performs so-called raw water backwashing in which the backwashing pump 14 is not provided and the pumping device 11 performs backwashing. For example, a three-way valve, which is a motor operated valve, is provided on the secondary side of the pump device 11 and on the primary side of the first three-way valve 33, and the pipe 23 is connected to the first port of the three-way valve, and the second port is connected to the second port. A pipe connected to the first three-way valve 33 is provided with a pipe connected to the second three-way valve 36 at the third port. The filtration device 1 having this configuration switches the three-way valve to connect the pump device 11 and the second three-way valve 36 and switches the first three-way valve 33 to connect the suction pipe 32 and the drain pipe 34 during backwashing. Then, the pump device 11 and the discharge pipe 35 are connected by switching the second three-way valve 36. Thereby, the filtration apparatus 1 can perform raw water backwashing. In addition, various modifications can be made without departing from the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Filtration apparatus, 11 ... Pump apparatus, 12 ... Filtration unit, 13 ... Reservoir tank, 14 ... Backwash pump, 15 ... Chemical solution injection apparatus, 16 ... Control panel, 21 ... Pump, 22 ... Motor, 23 ... Piping, 31 ... Filtration tank, 32 ... Suction pipe, 33 ... First three-way valve, 34 ... Drain pipe, 34a ... Flow rate adjusting valve, 35 ... Discharge pipe, 36 ... Second three-way valve, 37 ... Water supply pipe, 38 ... Backwash pipe, DESCRIPTION OF SYMBOLS 39 ... Temperature sensor, 51 ... Memory | storage part, 52 ... Control part, 61 ... Pump, 62 ... Motor, 63 ... Check valve, 64 ... Open / close valve, 99 ... Signal line, 100 ... Supply source, 110 ... Drain destination.

Claims (7)

A filtration tank containing a filter medium for filtering water passing from the primary side to the secondary side;
A drain pipe connected to the primary side of the filtration tank;
A backwash pump having a plurality of pumps for supplying the water filtered in the filtration tank to the secondary side of the filtration tank;
A filtration apparatus comprising: A storage tank that is provided on the secondary side of the filtration tank and stores water treated in the filtration tank;
A temperature sensor for detecting at least one of a water temperature of the water stored in the storage tank and a water temperature of the water supplied from the backwash pump to the filtration tank;
A storage unit in which the water temperature at which the backwashing expansion rate of the filter medium is a predetermined value is stored as a threshold value,
A controller that increases the number of pumps driven when the water temperature detected by the temperature sensor exceeds the threshold;
With
The filtration apparatus according to claim 1, wherein the backwash pump supplies the water stored in the storage tank to a secondary side of the filtration tank.   The filtration device according to claim 2, wherein the control unit increases the number of pumps to be driven when the water temperature detected by the temperature sensor continuously exceeds the threshold value for a predetermined time. A plurality of the threshold values are provided,
The filtration device according to claim 3, wherein the control unit sequentially increases the number of driven pumps when the water temperature detected by the temperature sensor sequentially exceeds the plurality of threshold values. Filtering water passing from the primary side to the secondary side, treated with a filtration tank containing a filter medium, and water stored in the storage tank by one pump of a backwash pump having a plurality of pumps, Supply from the secondary side of the filtration tank to the primary side of the filtration tank,
A temperature sensor detects at least one of the water temperature of the water stored in the storage tank and the water temperature of the water supplied from the backwash pump to the filtration tank,
The control unit compares the water temperature detected by the temperature sensor with the water temperature at which the backwashing expansion rate of the filter medium stored as a threshold value in the storage unit becomes a predetermined value,
When the water temperature detected by the temperature sensor exceeds the threshold, the control unit increases the number of pumps driven;
A control method for a filtration device.   6. The method of controlling a filtration device according to claim 5, wherein the number of pumps driven increases when the water temperature detected by the temperature sensor continuously exceeds the threshold value for a predetermined time. A plurality of the threshold values are provided,
6. The method of controlling a filtration device according to claim 5, wherein the controller sequentially increases the number of pumps that are driven when the water temperature detected by the temperature sensor sequentially exceeds the plurality of threshold values. .