JP2003299911A - Filter media cleaning system and water treatment system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter medium cleaning system capable of adjusting the flow velocity of cleaning water rapidly and accurately corresponding to the temperature of cleaning water, and a water treatment system equipped with the filter medium cleaning system. <P>SOLUTION: The filter medium cleaning system is equipped with a filter basin 3 for filtering water to be treated and a cleaning water storage basin 7 for storing cleaning water. The filter basin 3 has filter media 51 and 52. The filter basin 3 and the cleaning water storage basin 7 are connected by washing lines 26, 27 and 28 and a water temperature meter 58 and cleaning pump devices 32, 42, 34 and 43 are attached to the washing lines 26, 27 and 28. A cleaning treatment control unit 11 is connected to the water temperature meter 58 and the cleaning pump devices 32, 42, 34 and 43 and calculates the flow velocity of cleaning water optimum to the washing of the filter medium from the temperature of cleaning water to control the cleaning pumps 32, 42, 34 and 43. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter medium cleaning system for cleaning a filter medium in a filter basin, and a water treatment system including the filter medium cleaning system.

[0002]

2. Description of the Related Art Raw water for tap water is generally supplied as tap water after undergoing a predetermined purification treatment. A rapid filtration method is widely adopted as a method of such a predetermined purification process.

The rapid filtration system refers to a system in which the raw tap water is subjected to coagulation-sedimentation treatment to remove suspended substances as much as possible in the sedimentation tank, and then subjected to filtration treatment in the rapid filtration tank. Raw water is generally supplied as tap water after being disinfected with chlorine or the like. This rapid filtration method
It has excellent treatment capacity for suspended matter, and even when the turbidity of tap water is extremely high or fluctuates,
It is possible to treat large amounts of tap water in a short time.
Since the filtration speed is higher than that of the slow filtration method, it has a feature that the installation area of the entire raw water treatment facility can be reduced. For this reason, many water purification plants created after the war adopted the rapid filtration method.

In the filtration treatment in the rapid filtration pond, the raw tap water is caused to flow at a high speed through the filtration material arranged in the rapid filtration pond, so that suspended substances such as flocs in the raw tap water adhere to the filtration material or the filtration layer. Removed by sieving with. A relatively coarse material such as sand is used for the filter medium, and the filter medium is supported by a support material such as gravel.

When the above-mentioned filtration treatment is continued, suspended substances removed from the raw water of tap water are deposited on the filter medium and clogging occurs between the filter mediums, which lowers the filtration treatment capacity in the rapid filtration tank. If the filtration treatment capacity is lowered, the turbidity of the raw water of the tap water that has been subjected to the filtration treatment is increased, or the head loss is increased, making it difficult to obtain the required filtration flow rate. For this reason, when the water to be treated cannot be sufficiently filtered in the rapid filtration tank, it is necessary to wash the filter medium to remove suspended substances and regenerate the rapid filtration tank.

As a method of cleaning such a filter medium, so-called backwashing (backwashing), surface cleaning (surface washing), air cleaning (air washing), and a method of using these in combination are conceivable.

[0007]

As described above, when the raw tap water cannot be sufficiently filtered, it is necessary to wash the filter medium.

At this time, if the filter medium is not sufficiently washed, the time during which the filtration process can be continued decreases,
The amount of tap water that can be filtered is reduced, the filter layer is cracked, the filter layer surface becomes uneven, and a gap is created between the side wall of the quick filter and the filter layer. Large and easy to grow like a ball (mud ball),
Such various adverse effects may occur, and it may be difficult to perform an appropriate filtration process.

The cleaning of the filter medium is carried out by spraying cleaning water onto the filter medium until the entire filter layer is in a floating state, and bringing the filter mediums into contact with each other to collide with each other to separate the suspended substances from the filter medium. For this reason, various factors such as the flow rate of the washing water sprayed on the filter medium, the viscosity coefficient of the washing water, the density of the washing water, the particle size of the filter medium, etc. are complicatedly entangled with each other and affect the quality of the cleaning of the filter medium. For example, if the flow rate of wash water is too fast, the filter medium will flow out of the rapid filtration tank, while if the flow rate of wash water is too slow, it will be necessary to sufficiently remove suspended substances from the filter medium. It causes the inconvenience of being difficult. Therefore, the wash water has an optimum flow rate for washing the filter medium, and the optimum flow rate is the viscosity of the wash water,
It is determined based on the density of washing water, the particle size of the filter medium, and the like.

In general, the density and viscosity coefficient of water change depending on the water temperature, and have the relationship shown in Table 1 below (see Science Table, National Astronomical Observatory, ed.), And the higher the water temperature, the higher the water density. And the viscosity coefficient decreases.

[Table 1] Therefore, when the temperature of the wash water changes, the optimum flow rate of the wash water also changes. Therefore, it is difficult to properly wash the filter medium if the wash water is sprayed onto the filter medium at a constant flow rate, even though the temperature of the wash water changes. In particular, in the case where the climate changes drastically throughout the year and the water temperature of the wash water also changes drastically like Japan, the effect on the optimum flow velocity caused by the change in the water temperature of the wash water cannot be ignored.

Further, the flow velocity of the washing water is generally adjusted by an operator. When adjusting the flow rate of the wash water via the operator in this way, it is difficult to quickly adapt the flow rate of the wash water to changes in the temperature of the wash water, and the flow rate of the wash water should be optimized. It is also difficult to make precise adjustments. Further, the filter medium cannot be properly washed with the wash water that is not adjusted to the optimum flow rate, and the filtration treatment after washing the filter medium may be insufficient.

The present invention has been made in view of the above points, and a filter medium cleaning system capable of quickly and accurately adjusting the flow rate of the cleaning water according to the temperature of the cleaning water, and the filter medium cleaning system. It aims at providing the water treatment system provided with.

[0013]

The present invention has a filter medium,
A filter basin for filtering the water to be treated, a wash water storage basin for storing the wash water, a cleaning line connecting the filter basin and the wash water storage basin, and cleaning water attached to the cleaning line and flowing through the cleaning line Water temperature meter for measuring the water temperature of, a cleaning pump device attached to the cleaning line, capable of flowing the cleaning water of the cleaning water storage pond into the cleaning line at a desired flow rate, and connected to the water temperature meter and the cleaning pump device, And a cleaning processing control device for controlling the cleaning pump device on the basis of the optimum flow rate of the wash water, which is obtained from the temperature of the wash water sent from the water thermometer. It is a filter medium cleaning system characterized by that.

According to the present invention, the optimum flow rate of the wash water for washing the filter medium is determined according to the temperature of the wash water, and the flow rate of the wash water is automatically determined based on the obtained optimum flow rate of the wash water. Is adjusted to.

Further, a washing line anemometer attached to the washing line, for measuring the flow velocity of the washing water flowing through the washing line from the washing water storage basin to the filtration basin, and sending the measured value to the washing treatment control device is further provided. The cleaning process control device determines the cleaning pump device based on the optimum flow rate of the wash water obtained from the water temperature of the wash water sent from the water temperature meter and the flow rate of the wash water sent from the wash line anemometer. It is preferable to control. In this case, since the flow rate of the wash water is adjusted based on the obtained optimum flow rate of the wash water and the flow rate of the wash water actually flowing through the wash line, the flow rate of the wash water can be more accurately optimized. The flow rate can be adjusted automatically.

Further, the cleaning processing control device has a built-in relational expression between the temperature of the cleaning water and the flow rate of the cleaning water most suitable for cleaning the filter medium. It is preferable to determine the optimum flow rate of washing water for washing the filter medium by using it. In this case, the optimum flow rate of the cleaning water for cleaning the filter medium is determined based on the relational expression built into the cleaning process control device, and the cleaning water flow rate should be automatically adjusted to the optimum flow rate quickly and reliably. You can

The washing water flowing through the washing line is preferably used for backwashing the filter medium. Since the quality of backwashing of the filter medium is strongly influenced by the flow rate of the wash water, the filter medium can be effectively backwashed by adjusting the flow rate of the wash water to an optimum flow rate.

The present invention is directed to the above-described filter medium cleaning system, a filter pond inflow line for supplying the treated water to the filter pond, and a filter pond outflow for discharging the treated water filtered in the filter pond from the filter pond. A line, a filtration resistance measuring device that measures filtration resistance in the filtration pond, and a cleaning system control device that determines whether or not the filter material cleaning system is operating based on a measurement value sent from the filtration resistance measuring device. The water treatment system is characterized by

According to the present invention, whether or not the filter medium cleaning system is activated is determined based on the filtration resistance. Therefore, when impurities are deposited on the filter medium and the filtration resistance is increased, the cleaning system can be activated to perform the cleaning process on the filter medium.

The present invention is directed to the above-described filter medium cleaning system, a filter pond inflow line for supplying the treated water to the filter pond, and a filter pond outflow for discharging the treated water filtered in the filter pond from the filter pond. Based on the measurement value sent from the filtration processing time measurement device that measures the filtration processing time in the line and the filtration pond, the filtration material cleaning processing time measurement device that measures the cleaning time of the filtration material, and the filtration processing time measurement device And a cleaning system controller for determining whether or not the filter medium cleaning system is activated and determining whether or not the filter medium cleaning system is deactivated based on a measurement value sent from the filter medium cleaning processing time measuring device. Is a water treatment system.

According to the present invention, the cleaning system control device determines whether or not the filter medium cleaning system is activated based on the filtering process time, and determines whether or not the filter medium cleaning system is deactivated based on the filter medium cleaning process time. To do. Therefore, it is possible to appropriately prevent the impurities from accumulating on the filter medium due to the filtration treatment for a long time and the reduction of the filtration treatment capacity in the filtration basin.

The present invention comprises the above-described filter medium cleaning system, a filter pond inflow line for supplying the treated water to the filter pond, and a filter pond outflow for discharging the treated water filtered in the filter pond from the filter pond. A line, a filter pond discharge line that discharges washing water that has been used to wash the filter media, a treated water turbidity meter that measures the turbidity of the treated water that is sent from the filter pond to the filter pond outflow line, and a filter pond From the wash water turbidity meter that measures the turbidity of the wash water sent from the filter to the discharge line of the filter basin, and based on the measurement value sent from the treated water turbidity meter, determine whether the filter media cleaning system starts operating. And a cleaning system controller that determines whether or not the filter medium cleaning system is stopped based on a measurement value sent from the cleaning water turbidimeter.

According to the present invention, whether or not the filter medium cleaning system is started is determined based on the turbidity of the water to be treated, and whether or not the filter medium cleaning system is stopped is determined based on the turbidity of the cleaning water. . Therefore, it is possible to prevent the filter medium from being contaminated and appropriately secure an appropriate filtration treatment capacity in the filter basin.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment FIGS. 1 to 5 are views showing a first embodiment of the present invention. FIG. 1 is a schematic diagram showing the overall configuration of the water treatment system, and FIG. 2 is a diagram showing the opening and closing of each valve and the operating state of each pump in each step of the filtration treatment of the water to be treated and the washing treatment of the filter medium. Is. FIG. 3 is a flowchart showing the relationship between the filtering process of the water to be treated and the cleaning process of the filter medium,
FIG. 4 is a flow chart showing the flow of surface washing (back washing). FIG. 5 is a diagram showing the relationship between the correction coefficient and the water temperature of the wash water used when obtaining the optimum flow velocity of the backwash water.

As shown in FIG. 1, the water treatment system 1 includes
A filtration basin 3 for filtering treated water, a distribution basin 5 connected to the filtration basin 3 via a filtration basin outflow line 21, and a pump well connected to the distribution basin 5 via a distribution basin outflow line 22. 7 is provided.

In the filter basin 3, a filter sand 51 is used as a filter medium.
And the filtering gravel 52 are arranged, and the lower water collecting device 5 is provided below the filtering sand 51 and the filtering gravel 52.
3 are arranged. The water to be treated that has flowed into the filtration pond 3 is
After being filtered by the filtering sand 51 and the filtering gravel 52, the water is collected by the lower water collecting device and sent to the filter pond outflow line 21. In addition, filter pond 3
A surface washing device 54 and a drain trough 55 are installed inside. The surface washing device 54 is a washing line 27 for surface washing described later.
Filter sand mainly using the wash water sent through
1 can be surface-washed. On the other hand, in the drainage trough 55, impurities such as suspended substances in the wash water flow in when washing the filtering sand 51 and the filtering gravel 52, and the impurities flowing in the drainage trough 55 are stored in the filtration pond 3. It is designed to be discharged outside. Furthermore,
A water level gauge 56 for the filter is provided in the filter 3.
The water level gauge 56 for the filtration pond measures the water level in the filtration pond 3 and sends the measured value to the cleaning system control device 9 described later.

In addition, the filter basin 3 has a filter basin inflow line 23.
The treated water of the settling basin, which is arranged in the preceding stage of the filtering basin 3, to which the filtering basin discharge line 24 is attached, flows into the filtering basin 3 via the filtering basin inflow line 23, Further, the wash water in the filter basin 3 is discharged to the wash distribution reservoir via the filter basin discharge line 24.

The pump well 7 is connected to a subsequent stage of the water treatment system 1 via a pump well outflow line 25 to which a water distribution pump 41 is attached. Pump well outflow line 2
In Fig. 5, a cleaning line 26 is branched between the pump well 7 and the water distribution pump 41, and the cleaning line 26 is branched into a surface cleaning line 27 and a backwashing cleaning line 28. The washing line 27 for surface washing is connected to the surface washing device 54 arranged in the filtration pond 3, and the washing line 2 for backwashing is also used.
8 is connected to the filter pond outflow line 21.

A treated water turbidity meter 46 is provided at a stage subsequent to the connection position of the backwashing cleaning line 28 in the outflow line 21 of the filter basin.
A filtered water flowmeter 57 and a filter pond outflow valve 31 are sequentially installed. The treated water turbidity meter 46 measures the turbidity of the filtered treated water in the outflow line 21 of the filter basin and sends the measured value to the cleaning system controller 9. The filtered water flow meter 57 measures the flow rate of the filtered treated water that flows through the filter basin outflow line 21, and sends the measured treated water flow rate to the cleaning system control device 9 described later. The filter pond outflow valve 31 is
The flow rate of the water to be treated in the filter basin outflow line 21 can be adjusted by being controlled by the cleaning system controller 9.

A water temperature gauge 58 is attached to the cleaning line 26. The water temperature meter 58 measures the water temperature of the cleaning water flowing through the cleaning line 26 and sends the measured value to the cleaning processing control device 11.

Further, in the cleaning line 27 for surface cleaning, the surface cleaning pump 42, the surface cleaning flow meter 44, and the surface cleaning flow rate control valve 32.
And the surface washing valve 33 are sequentially attached. The surface cleaning pump 42 is controlled by the cleaning processing control device 11 to send cleaning water from the cleaning line 26 to the surface cleaning line 27. The surface-wash flow meter 44 is a cleaning line 2 for surface-wash
The flow rate of the cleaning water flowing through 7 is measured, and this measured value is sent to the cleaning processing control device 11. The surface-washing flow rate control valve 32 is controlled by the cleaning processing control device 11 so that the flow rate of the cleaning water flowing through the surface-cleaning cleaning line 27 can be adjusted. The surface cleaning valve 33 is controlled by the cleaning system controller 9 to transfer the cleaning water in the surface cleaning line 27 to the surface cleaning device 54.
It is possible to adjust whether or not to send to.

Further, in the backwash cleaning line 28, a backwash pump 43, a backwash flow meter 45, and a backwash flow control valve 34.
And a backwash valve 35 are sequentially attached. The backwash pump 43 is controlled by the washing processing control device 11 to send washing water from the washing line 26 to the backwashing washing line 28. The backwash flow meter 45 is used for the backwash cleaning line 2
The flow rate of the washing water flowing through 8 is measured, and this measured value is sent to the washing processing control device 11. The backwash flow control valve 34 is controlled by the cleaning processing control device 11 so that the flow rate of the wash water flowing through the backwash cleaning line 28 can be adjusted. The backwash valve 35 is controlled by the washing system control device 9 and is capable of adjusting whether or not the washing water in the washing line 28 for backwashing is sent to the filtration basin 3.

A filter pond inlet valve 3 is provided in the filter pond inlet line 23.
6 is attached. The filter basin inlet valve 36 is controlled by the cleaning system controller 9 so that the flow rate of the water to be treated flowing through the filter basin inlet line 23 can be adjusted.
Further, a drain valve 37 and a wash water turbidity meter 47 are sequentially attached to the filter basin discharge line 24. The drain valve 37 is
Under the control of the cleaning system controller 9, the flow rate of the cleaning water flowing through the filter basin discharge line 24 can be adjusted.
The cleaning water turbidity meter 47 measures the turbidity of the cleaning water flowing through the filter basin discharge line 24 and sends the measured value to the cleaning system controller 9.

Further, the water treatment system 1 is provided with a cleaning system control device 9 and a cleaning treatment control device 11.

The cleaning system controller 9 controls the filter basin inlet valve 36 and the filter based on the measured values sent from the treated water turbidity meter 46, the filter basin level gauge 56 and the cleaning water turbidity meter 47, respectively. Pond outflow valve 31, surface wash valve 33, backwash valve 35, drain valve 3
The cleaning process control device 11 is controlled while controlling the opening and closing of each of the cleaning devices 7. Further, the cleaning system control device 9 is adapted to obtain the flow velocity from the flow rate of the water to be treated in the filter basin outflow line 21 sent from the filtered water flow meter 57.

The flow velocity of the water to be treated flowing through the filter pond outflow line 21 is from the filtered water velocity meter 57 to the cleaning system controller 9
It is obtained by dividing the flow rate (m ³ / min) of the water to be treated sent to the tank by the cross-sectional area (m ² ) of the outflow line 21 of the filter basin.

On the other hand, the cleaning treatment control device 11 has a built-in relational expression between the temperature of the cleaning water and the flow rate of the cleaning water most suitable for cleaning the filtering sand and the filtering gravel. The cleaning processing control device 11 is controlled by the cleaning system control device 9,
By using the built-in relational expression and the water temperature of the wash water sent from the water thermometer, the optimum wash speed of the wash water used for the surface wash and the backwash can be obtained. Further, the cleaning processing control device 11 divides the flow rate of the cleaning water sent from the front-wash flow meter 44 or the back-wash flow meter 45 by the cross-sectional area of the front-wash cleaning line 27 or the back-wash cleaning line 28. Thus, the flow velocity of the water to be treated flowing through the surface washing line 27 or the back washing line 28 is obtained. Then, the cleaning processing control device 11 controls the surface washing pump 42 and the backwashing pump 43 based on the obtained optimum cleaning speed and the flow rate of the washing water flowing through the surface washing line 27 and the backwashing line 28. Each of them is drive-controlled, and the opening / closing of the surface-washing flow rate adjusting valve 32 and the backwashing flow rate adjusting valve 34 is controlled.

Therefore, in this embodiment, the pump well 7 constitutes the flush water storage pond of the present invention. Further, (i) cleaning line 26 and surface cleaning line 27, (ii) cleaning line 26, backwashing cleaning line 28 and backwashing cleaning line 2
The filter pond outflow line 2 between the connection position of 8 and the filter 3
Each of 1 and 1 constitutes the cleaning line of the present invention. Further, (i) the surface washing pump 42 and the surface washing flow rate control valve 32 (i
i) Each of the backwash pump 43 and the backwash flow control valve 34,
It constitutes the cleaning pump device of the present invention. The cleaning system control device 9 and the cleaning process control device 11 constitute the cleaning process control device of the present invention. Also, the front-wash flow meter 4
4 and the cleaning process control device 11, the backwash flow meter 45, and the cleaning process control device 11 constitute a cleaning line anemometer of the present invention. Further, the filter medium cleaning system according to the present embodiment includes a filter basin 3, a pump well 7, a cleaning line 26, a surface cleaning cleaning line 27, a back cleaning cleaning line 28, a water temperature meter 58, a surface cleaning pump 42, and a surface cleaning flow rate. It has a control valve 32, a backwash pump 43, a backwash flow rate adjusting valve 34, a surface wash flowmeter 44, a backwash flowmeter 45, and the cleaning processing control device 11.

Next, the operation of the present embodiment having such a configuration will be described.

First, water treatment including filtration treatment in the water treatment system 1 shown in FIG. 1 will be outlined.

When performing the water treatment, the filter basin inlet valve 36 and the filter basin outlet valve 31 are opened, and the drain valve 37, the surface wash valve 33, and the backwash valve 35 are closed. Therefore, the water to be treated can be circulated in each of the filtration basin inflow line 23, the filtration basin outflow line 21, the distribution reservoir outflow line 22, and the pump well outflow line 25.

The water to be treated as the tap water is subjected to a sedimentation treatment in the sedimentation basin, and then sent to the filtration basin 3 through the filtration basin inflow line 23. The water to be treated sent to the filtration pond 3 is filtered by the filtration sand 51 and the filtration gravel 52, which are filter media, collected by the lower water collecting device 53, and sent to the filtration pond outflow line 21. The water level of the water to be treated in the filter basin 3 is measured by the water level gauge 56 for the filter basin and sent to the cleaning system controller 9. Impurities such as suspended substances in the water to be treated are removed by the filtering sand 51 and the filtering gravel 52 by this filtering process, so that the impurities accumulate on the filtering sand 51 and the filtering gravel 52 as the filtering process progresses. However, the filtration processing capacity of the filtration basin 3 decreases.

The water to be treated is sent to the distribution reservoir 5 from the filtration reservoir 3 through the filtration reservoir outflow line 21. At this time, the turbidity of the treated water that has been subjected to the filtration treatment flowing through the filter pond outflow line 21 is measured by the treated water turbidity meter 46, and the flow rate is measured by the filter pond flow meter 57. Then, the treated water turbidity meter 46 and the filter pond flow meter 57 respectively send measured values to the cleaning system controller 9.

The water to be treated sent to the distribution reservoir 5 is the distribution reservoir 5.
A certain amount of water is stored in the reservoir and is sent to the pump well 7 from the reservoir 5 via the reservoir outflow line 22. Then, the water to be treated in the pump well 7 is sent to the subsequent stage of the water treatment system 1 through the pump well outflow line 25 by the water distribution pump 41. The amount of water to be treated supplied from the distribution reservoir 5 to the pump well 7 is adjusted so that the water to be treated can be stably sent to the subsequent stage of the water treatment system 1.

Next, the steps of cleaning the filtering sand 51 and the filtering gravel 52 (filter material) in the filter basin 3 will be described with reference to FIGS.

In the above-mentioned water treatment process, when the turbidity of the treated water sent from the treated water turbidity meter 46 to the cleaning system controller 9 reaches a predetermined turbidity, the treated water is filtered. The treatment is interrupted and the filtration sand 51 and the filtration gravel 52 in the filtration pond 3 are washed.

That is, when the treated water is being filtered (STEP 1 in FIG. 3), the cleaning system controller 9 sets the turbidity of the treated water sent from the treated water turbidity meter 46 to a predetermined value. When the turbidity of the filter is reached (STEPA2), a control signal is first sent to the filter basin inlet valve 36 to send the filter basin inlet valve 3
6 is fully closed (STEPA 3) so that the water to be treated in the sedimentation tank is not sent to the filtration tank 3. Then, the filtration treatment of the water to be treated in the filtration pond 3 is continued (STEPA 4), and the water level in the filtration pond 3 is lowered.

At this time, when the water level in the filter basin 3 sent from the filter basin water level gauge 56 to the cleaning system controller 9 decreases to a predetermined water level (STEPA5), the cleaning system controller 9 causes the filter basin A control signal is sent to the outflow valve 31 to fully close the outflow valve 31. Then, the cleaning system controller 9 sends a control signal to the drain valve 37 to send the drain valve 3
7 is fully opened (STEPA6).

Then, the cleaning system control device 9 sends a control signal to the cleaning process control device 11 to perform surface washing and backwashing of the filtering sand 51 and the filtering gravel 52 in the filtration basin 3 (STEPA7).

That is, the cleaning process control device 11 sends a control signal to the surface-washing flow rate control valve 32 to send the surface-washing flow rate control valve 32.
Open (STEP B1 in Fig. 4), and the surface washing pump 4
2 to send a control signal to drive the surface washing pump 42 (ST
EPB2). As a result, the filtered treated water stored in the pump well 7 flows into the surface washing line 27 as the washing water through the pump well outflow line 25 and the washing line 26, and the surface water in the filtration pond 3 is washed. It is sent to the washing device 54. Then, the surface washing device 54 starts surface washing of the filtering sand 51 and the filtering gravel 52 using the sent wash water (STEP B3).

Further, the backwashing of the filtering sand 51 and the filtering gravel 52 is carried out in the same manner as the case of carrying out the surface washing. That is, the cleaning processing control device 11 sends a control signal to the backwash flow control valve 34 and the backwash pump 43 to send the backwash flow control valve 34.
Is opened (STEPB1) and the backwash pump 43 is driven (STEPB2). As a result, the water to be treated stored in the pump well 7 is passed through the pump well outflow line 25 and the cleaning line 26 as the cleaning water, and then the backwash cleaning line 2
After flowing into the filter 8, it flows into the filtered water discharge line, flows backward through the filtered water discharge line, and is sent into the filtration basin 3. Then, the wash water flows backward in the filtration pond 3 to obtain the filtration sand 51.
And backwashing of the filtering gravel 52 is started (STEPB
3).

When the filtration sand 51 and the filtration gravel 52 are surface-washed or backwashed as described above, the water temperature of the washing water flowing through the washing line 26 is measured by the water temperature meter 58 to the washing treatment control device 11. It is sent (STEP B4).

Then, the cleaning treatment control device 11 is based on the water temperature of the cleaning water sent from the water temperature gauge 58 and the built-in relational expression, and is suitable for cleaning the filtering sand and the filtering gravel. Obtain the flow velocity (optimal flow velocity of washing water) (STEP
B5). For example, in the case of backwashing, the optimum flow rate of wash water is obtained by the following relational expression using FIG.

FIG. 5 is a graph showing the relationship between the temperature of the wash water during backwashing and the correction coefficient for the optimum flow rate of the wash water (Journal of the Water Works Association, No. 455, Sho 47.8, "Rapid Filtration Pond"). "Hydraulic consideration of specifications regarding cleaning in.").
In FIG. 5, μ20 means 1 c.p = 10 ⁻³ kg / m · sec, and μ means the viscosity coefficient of backwash water. At this time, for example, it is assumed that the optimum flow rate V ₂₀ of washing water when the water temperature is 20 ° C. is V ₂₀ = 0.74 m / min. In this case, since the correction coefficient is 0.825 when the water temperature is 0 ° C. (see FIG. 5), the optimum wash water flow velocity V ₀ at this time is as follows. V ₀ = V ₂₀ × correction coefficient = 0.74 m / min × 0.825
= 0.61 m / min Similarly, the correction coefficient when the water temperature is 30 ° C. is 1.080 (see FIG. 5), so the optimum wash water flow velocity V ₃₀ at this time is as follows. V ₃₀ = V ₂₀ × correction coefficient = 0.74 m / min × 1.08
Also in the case of 0 = 0.80 m / min surface cleaning, the cleaning processing control apparatus 11 separately determines the optimum flow rate of cleaning water for surface cleaning based on the temperature of the cleaning water.

On the other hand, the flow rate of the cleaning water flowing through the surface cleaning line 27 is measured by the surface cleaning flow meter 44 and sent to the cleaning processing control device 11. Similarly, the flow rate of the cleaning water flowing through the backwash cleaning line 28 is measured by the backwash flow meter 45 and sent to the cleaning processing control device 11. Then, the cleaning processing control device 11 obtains the flow rate of the cleaning water in the surface cleaning line 27 from the flow rate of the surface cleaning water sent from the surface cleaning flow meter 44, and the backwash flow meter 4
The flow rate of the washing water in the washing line for backwashing 28 is obtained from the flow rate of the washing water for backwashing sent from No. 5 (STEPB
6).

Then, the cleaning processing control device 11 considers the deviation between the obtained optimum flow rate of the wash water in the case of the surface wash and the flow rate of the wash water in the surface wash line 27, and adjusts the surface wash flow control valve. A control signal is sent to 32, and the surface washing flow rate control valve 32 is adjusted so that the flow rate of the washing water flowing through the surface washing line 27 becomes the optimum washing water flow rate (STEP B7). This allows
The flow rate of the wash water sent to the surface washing device 54 is automatically adjusted to the optimum flow rate of the wash water, and the filtering sand 51 and the filtering gravel 52 are effectively surface washed.

Also in the case of backwashing, similarly, the cleaning treatment control device 11 considers the deviation between the obtained optimum flow rate of wash water in the case of backwashing and the flow rate of wash water in the backwashing cleaning line 28. Then, the backwash flow control valve 34 is adjusted so that the flow rate of the wash water for the backwash becomes the optimum flow rate of the wash water, and the backwash sand 51 and the gravel 52 for the backwash are effectively backwashed.

The impurities removed from the filtering sand 51 and the filtering gravel 52 by carrying out the surface washing and the back washing float in the washing water and flow into the drainage trough 55. Further, the cleaning water in the filter basin 3 is discharged from the filter basin discharge line 24 and sent to the cleaning drainage basin.

At this time, the wash water turbidity meter 47 measures the turbidity of the wash water flowing through the filter basin discharge line 24, and sends the measured value to the wash system controller 9 (STEP B8).
Then, from the washing water turbidity meter 47 to the washing system controller 9
When the turbidity of the wash water sent to is reduced to the “predetermined turbidity”, the front wash valve 33 is fully closed, and then the backwash valve 35 is fully closed. Then, the driving of the surface wash pump 42 is stopped and the surface wash flow rate control valve 32 is fully closed, and the driving of the backwash pump 43 is stopped and the backwash flow rate control valve 34 is fully closed (STEP B9). In this way, the surface washing and backwashing of the filtering sand 51 and the filtering gravel 52 are completed (STEP B10).

The "predetermined turbidity" in this case is arbitrary depending on operating conditions. For example, when the measured value of the turbidity of the wash water measured by the wash water turbidity meter 47 is reduced to 0.1 degrees, it is possible to end the above-mentioned surface washing and backwashing. It is possible to make every possible effort to prevent protozoa such as Cryptosporidium.

Thereafter, the drain valve 37 is fully closed and the filter pond inflow valve 36 is fully opened. As a result, the water to be treated flows into the filtration basin 3. After that, the filter basin outflow valve 31 is fully opened (STEPA8). As a result, the water to be treated in the filter basin 3 is filtered by the filtering sand 51 and the filtering gravel 52, collected by the lower water collecting device 53, and sent to the distribution reservoir 5 via the filtering basin outflow line 21. To be

The filtering sand 51 and the filtering gravel 52, which have been contaminated with impurities by the filtering process, are automatically washed as described above. Further, when the washing of the filtering sand 51 and the filtering gravel 52 is completed, the filtering process of the water to be treated is automatically restarted.

As described above, according to the present embodiment, the washing water used for the surface washing or backwashing of the filtering sand 51 and the filtering gravel 52, which are the filter media, is changed depending on the water temperature.
The flow rate is adjusted to be optimum for washing the filter medium. Thereby, even in an environment where the water temperature of the wash water changes, the filter medium can be washed with the wash water at the optimum flow rate, and the filtering sand 51 and the filtering gravel 52 (filter medium) can be washed appropriately and reliably. .

Further, as described above, opening and closing of the filter basin inlet valve 36, the drain valve 37, the filter basin outlet valve 31, the surface wash valve 33, and the backwash valve 35 are performed by the treated water turbidity meter 46 and the washed water turbidity. 47 in total
And it is automatically adjusted based on the measured value of the water level meter 56 for the filter basin. Therefore, the process of filtering the water to be treated and the process of washing the filter medium are automatically switched.

The water temperature of the wash water is automatically measured by the water temperature gauge 58. Further, the flow rate of the cleaning water flowing through the surface cleaning line 27 or the back cleaning line 28 is automatically determined by the cleaning processing control device 11 based on the flow rate measured by the surface cleaning flow meter 44 or the back cleaning flow meter 45. Is required. Further, the cleaning treatment control device 11 automatically calculates the optimum flow rate of the cleaning water based on the water temperature, and the calculated value and the surface wash flowmeter 44 or the backwash flowmeter 4
Based on the measured value of 5, the opening and closing of the surface wash flow rate control valve 32 and the backwash flow rate control valve 34 that adjust the flow rate of the wash water are automatically adjusted. Therefore, the cleaning process of the filter medium is automatically performed.

As described above, by automatically switching between the filtering process of the water to be treated and the cleaning process of the filter medium and the cleaning process of the filter medium, the automatic operation can be performed unattended without operator intervention. Therefore, it is possible to perform the filtering treatment of the water to be treated and the washing treatment of the filter medium. Therefore, the filtering process of the water to be treated and the cleaning process of the filter medium are automatically performed regardless of the time zone or the season.

Further, in the present embodiment, the treated water turbidity meter 4
6 starts the cleaning treatment of the filter medium based on the turbidity of the water to be treated flowing out from the filter basin 3, and the filter medium based on the turbidity of the wash water flowing out from the filter basin 3 by the wash water turbidity meter 47. The cleaning process in step 1 is completed. In this way, the filtration pond 3
By starting and ending the cleaning treatment of the filter medium based on the turbidity of the treated water and the wash water flowing out from the water, it is possible to prevent the excessively contaminated treated water from being sent to the distribution reservoir 5 and to prevent the contamination of the filter medium. It is possible to appropriately perform the appropriate cleaning treatment of the filter medium. Also, a properly washed sand for filtration 5
By using 1 and the gravel 52 for filtration, it is possible to effectively carry out the filtration treatment of the water to be treated, and it is also possible to effectively prevent protozoa such as Cryptosporidium.

Next, a modification of the present embodiment will be described. A distribution reservoir cleaning line 29 that connects the distribution reservoir outflow line 22 and the cleaning line 26 is installed, and the treated water stored in the distribution reservoir 5 is used as cleaning water for the surface cleaning line 27 and the back cleaning line. 28 may be supplied. Others are substantially the same as those in the above-described first embodiment.

In this case, the water to be treated as the cleaning water stored in the distribution reservoir 5 is supplied to the distribution reservoir outflow line 22, the distribution reservoir cleaning line 29, and the cleaning line 26 by the surface washing pump 42 or the backwash pump 43. Through the washing line 27 for surface washing or the washing line 28 for back washing.

Incidentally, the filtering sand 51 and the filtering gravel 52
The surface washing or back washing is performed using the water to be treated stored in the distribution reservoir 5 in the same manner as in the first embodiment described above.

Thus, even if the wash water storage basin of the present invention is constituted by the distribution basin and the treated water stored in the distribution basin 5 is used as the cleaning water, the surface of the filter medium in the filtration basin 3 is washed. It is possible to properly carry out backwashing.

Second Embodiment Instead of installing the treated water turbidity meter 46 and the washing water turbidity meter 47, a timer device 59 for measuring the duration of the filtering process and the duration of the cleaning process of the filter medium is used. It is incorporated in the system controller 9 (see FIG. 1).

The cleaning system control device 9, based on the measured value of the timer device 59 and the measured value of the water level gauge 56 for the filter basin, the filter basin inlet valve 36, the drain valve 37, the surface wash valve 33,
The opening / closing of the backwash valve 35 and the filtration basin outflow valve 31 is adjusted, and the cleaning processing control device 11 is controlled. Therefore, the timer device 59 constitutes the filtration processing time measuring device and the filtering material cleaning processing time measuring device of the present invention.

Others are substantially the same as those in the first embodiment. The same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The water to be treated which has flowed into the filter basin 3 is filtered by the filtering sand 51 and the filtering gravel 52 and sent to the filtering basin outflow line 21 by the lower water collecting device 53.

At this time, the duration of the filtering process in the filter basin 3 is measured by the timer device 59. When the duration of this filtration process reaches a predetermined duration, the filtration process of the water to be treated is interrupted and the filter medium in the filter basin 3 is washed, as in the first embodiment described above. I do.

That is, the cleaning system control device 9 controls the opening / closing of the filter basin inlet valve 36, the filter basin outlet valve 31, the drain valve 37, the surface wash valve 33, and the backwash valve 35, and
The cleaning process control device 11 is controlled. The opening and closing of the filter pond outflow valve 31 and the drain valve 37 are performed based on the filter pond water level gauge 56.

Then, the cleaning treatment control device 11 uses the filtered treated water stored in the pump well 7 as cleaning water, and uses the water temperature meter 58, the surface washing pump 42, the surface washing flow meter 44, and the table. The washing flow rate adjusting valve 32, the backwashing pump 43, the backwashing flow meter 45, and the backwashing flow rate adjusting valve 34 are controlled to perform surface washing and backwashing of the filtering sand 51 and the filtering gravel 52 in the filtration pond 3. .

At this time, the timer device 59 measures the duration of the washing process by the surface washing and the duration of the washing process by the back washing. Then, when the duration of the cleaning process by the surface cleaning measured by the timer device 59 reaches a predetermined duration, the cleaning system control device 9 fully closes the surface cleaning valve 33, as in the first embodiment. The cleaning processing control device 11 stops the driving of the surface cleaning pump 42 and fully closes the surface cleaning flow rate control valve 32, so that the filtering sand 51 and the filtering gravel 5 are removed.
Finish the surface washing of 2. At the same time, when the duration of the cleaning process by the backwash measured by the timer device 59 reaches a predetermined duration, the cleaning system controller 9 fully closes the backwash valve 35 and the cleaning process controller 11 backwashes. The driving of the pump 43 is stopped and the backwash flow control valve 34 is fully closed to complete the backwash of the filtering sand 51 and the filtering gravel 52.

After the surface washing and backwashing are completed, the drain valve 37, the filter basin inlet valve 36, and the filter basin outlet valve 31.
Is adjusted to supply the water to be treated from the settling basin to the filtration basin 3 for filtering treatment, and then the water to be treated after the filtration treatment is sent to the distribution reservoir 5 through the filtration basin outflow line 21.

As described above, according to the present embodiment, based on the duration of the filtering process measured by the timer device 59 and the duration of the cleaning process by the surface washing and the back washing of the filter material, The treated water is filtered and the filter material is washed. As a result, it is possible to automatically perform stable filtration processing and cleaning processing, and to properly perform the filtration processing of the water to be treated and the cleaning of the filtering sand 51 and the filtering gravel 52.

The cleaning system control device 9 of the third embodiment is arranged such that, instead of the turbidity of the filtered treated water measured by the treated water turbidity meter 46, the filtering resistance in the filtering treatment in the filtration basin 3 is used. Based on the above, it is determined whether or not the operation of the filter basin 3 cleaning system is started. The filtration resistance is obtained by the cleaning system control device 9 based on the water level in the filtration pond 3 sent from the filtration pond water level gauge 56. Therefore, in the present embodiment, the water level gauge 56 for the filtration pond constitutes the filtration resistance measuring device of the present invention.

Others are substantially the same as those of the first embodiment. The same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The water to be treated which has flowed into the filter basin 3 is filtered by the filtering sand 51 and the filtering gravel 52 and sent to the filtering basin outflow line 21 by the lower water collecting device 53.

At this time, the water level of the treated water in the filter basin 3 is
It is measured by the water level gauge 56 for the filtration pond and sent to the cleaning system controller 9. Then, the cleaning system control device 9 obtains the filtration resistance in the filtration basin 3 based on the water level in the filtration basin 3 being sent. That is, when the amount of treated water flowing into the filtration basin 3 is constant, the higher the filtration resistance, the higher the water level in the filtration basin 3. Therefore, the cleaning system control device 9 determines that the higher the water level sent from the water level gauge 56 for the filtration pond, the higher the filtration resistance.

The cleaning system control device 9 judges that the filtration resistance of the filtration process has reached a predetermined value when the water level sent from the filtration pond water level gauge 56 has reached a predetermined water level, As in the first embodiment, the filtering process of the water to be treated is interrupted to wash the filter medium in the filter basin 3.

That is, the cleaning system control device 9 controls the opening and closing of the filter basin inlet valve 36, the filter basin outlet valve 31, the drain valve 37, the surface wash valve 33, and the backwash valve 35, and
The cleaning process control device 11 is controlled. The opening and closing of the filter pond outflow valve 31 and the drain valve 37 are performed based on the filter pond water level gauge 56.

Then, the cleaning treatment control device 11 uses the filtered treated water stored in the pump well 7 as the cleaning water, and uses the water temperature meter 58, the surface washing pump 42, the surface washing flow meter 44, and the table. The washing flow rate adjusting valve 32, the backwashing pump 43, the backwashing flow meter 45, and the backwashing flow rate adjusting valve 34 are controlled to perform surface washing and backwashing of the filtering sand 51 and the filtering gravel 52 in the filtration pond 3. .

Then, as in the first embodiment described above, the turbidity of the wash water sent from the wash water turbidity meter 47 through the filter basin discharge line 24 is reduced to the "predetermined turbidity". If so, the surface washing and back washing are completed. That is,
The surface wash valve 33 is fully closed, the backwash valve 35 is fully closed, the driving of the surface wash pump 42 is stopped, the surface wash flow rate control valve 32 is fully closed, the operation of the backwash pump 43 is stopped, and the reverse operation is performed. Wash flow control valve 3
4 is fully closed. Then, after the surface washing and the back washing are completed, the opening / closing of the drain valve 37, the filter basin inlet valve 36, and the filter basin outlet valve 31 is adjusted to supply the water to be treated from the settling basin to the filter basin 3 for filtering treatment. After that, the water to be treated is sent to the distribution reservoir 5 through the filtration reservoir outflow line 21.

As described above, according to the present embodiment, the operation of the cleaning system for the filtration pond 3 is started based on the filtration resistance in the filtration treatment in the filtration pond 3 obtained from the water level in the filtration pond 3. The presence or absence of is determined. This filtration resistance is
Especially, when the filtration sand 51 and the filtration gravel 52 are clogged due to impurities in the water to be treated and it becomes impossible to perform an appropriate filtration treatment, the increase is increased. Therefore, in the present embodiment, before the filtration sand 51 and the filtration gravel 52 are contaminated with impurities in the water to be treated and the appropriate filtration treatment cannot be performed, a proper cleaning treatment of the filter medium is quickly performed. be able to.

There are various types such as an electrode type in the water level gauge 56 for the filter basin. Further, instead of the water level gauge 56 for the filtration pond, the filtration resistance in the filtration pond 3 may be obtained by other means. For example, filtering sand 51 and filtering gravel 5
It is also possible to install a water pressure gauge for obtaining the water pressure difference between the water to be treated before and after being filtered in 3, and to obtain the filtration resistance from the water pressure difference.
In addition, the filter pond outflow line 2 measured by the filtered water flow meter 57
The filtration resistance may be obtained from the flow rate of the water to be treated flowing through 1. A combination of the above-described respective embodiments is also included within the scope of the present invention.

[0093]

As described above, according to the present invention, the cleaning treatment control apparatus determines the optimum flow rate of the cleaning water for cleaning the filter medium according to the temperature of the cleaning water, and determines the optimum cleaning water flow rate. The wash pump device can be controlled to flow at a flow rate. Accordingly, the flow rate of the wash water can be quickly and accurately adjusted according to the temperature of the wash water, and the filter medium is effectively washed with the wash water having the optimum flow rate.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the overall configuration of a water treatment system.

FIG. 2 is a diagram showing an opening / closing state of each valve and an operating state of each pump in each process of filtering treatment of water to be treated and washing treatment of a filter medium.

FIG. 3 is a flowchart showing the relationship between the filtration process of the water to be treated and the cleaning process of the filter material.

FIG. 4 is a flowchart showing a flow of surface washing (back washing).

FIG. 5 is a diagram showing a relationship between a correction coefficient and a water temperature of wash water used when obtaining an optimum flow velocity of wash water for backwash.

[Explanation of symbols]

1 Water treatment system 3 filtration ponds 5 distribution reservoir 7 pump wells 9 Cleaning system controller 11 Cleaning process control device 21 Filter pond outflow line 22 Distribution reservoir outflow line 23 Filter pond inflow line 24 Filter pond discharge line 25 Pump well outflow line 26 Washing line 27 Washing line for surface washing 28 Backwashing line 29 Distribution reservoir cleaning water line 31 Filter pond outflow valve 32 Surface wash flow control valve 33 surface wash valve 34 Backwash flow control valve 35 Backwash valve 36 Filter pond inflow valve 37 drain valve 41 water pump 42 surface wash pump 43 Backwash pump 44 Surface wash flow meter 45 Backwash flow meter 46 Treated water turbidity meter 47 Wash water turbidimeter 51 Filtering sand 52 Gravel for filtration 53 Lower water collecting device 54 Surface washing device 55 drainage trough 56 Water level gauge for filtration pond 57 Filtered water flow meter 58 Water thermometer 59 timer device

Claims (7)

[Claims] 1. A filter basin having a filter medium for filtering treated water, a wash water storage basin for storing wash water, a cleaning line connecting the filter basin and the wash water storage basin, and a cleaning line. Attached to the water temperature gauge for measuring the water temperature of the washing water flowing through the washing line, and a washing pump device attached to the washing line for allowing the washing water in the washing water storage pond to flow to the washing line at a desired flow rate. Connected to the meter and the washing pump device, the optimum washing water flow rate for washing the filter medium is obtained from the washing water temperature measured by the water temperature gauge, and the washing pump device is controlled based on this optimal washing water flow rate. And a cleaning processing control device. 2. A washing line anemometer attached to the washing line, for measuring the flow velocity of the washing water flowing through the washing line from the washing water storage basin to the filtration basin, and sending the measured value to the washing treatment control device. The cleaning process control device controls the cleaning pump device based on the optimum flow rate of the wash water obtained from the water temperature of the wash water measured by the water temperature gauge and the wash water flow rate measured by the wash line anemometer. The filter medium cleaning system according to claim 1, which is characterized in that. 3. The cleaning treatment control device has a built-in relational expression between the temperature of the washing water and the flow velocity of the washing water most suitable for washing the filter medium. The filter medium cleaning system according to any one of claims 1 and 2, wherein a flow rate of cleaning water most suitable for cleaning the filter medium is obtained by using the filter medium. 4. The cleaning water flowing through the cleaning line is used for backwashing the filter medium.
The filter medium cleaning system according to any one of the above. 5. The filter medium cleaning system according to claim 1, a filter basin inflow line for supplying water to be treated to the filter basin, and a subject to be treated which has been filtered in the filter basin. A filter pond outflow line that discharges water from the filter pond, a filtration resistance measurement device that measures the filtration resistance in the filtration pond, and a filter media cleaning system that is connected to the filtration resistance measurement device and is based on the filtration resistance measured by the filtration resistance measurement device. And a cleaning system control device that determines whether or not to operate the water treatment system. 6. The filter medium cleaning system according to claim 1, a filter basin inflow line for supplying water to be treated to the filter basin, and a subject to be treated which has been filtered in the filter basin. A filtration pond outflow line for flowing water from the filtration pond, a filtration treatment time measurement device for measuring the filtration treatment time in the filtration pond, a filtration medium cleaning treatment time measurement device for measuring the filtration time of the filtration medium, and a filtration treatment time measurement device. Whether the filter medium cleaning system is started or not is determined based on the measurement value sent from the device, and whether the filter medium cleaning system is stopped or not is determined based on the measurement value sent from the filter medium cleaning time measuring device. A water treatment system comprising: a cleaning system controller. 7. The filter medium cleaning system according to claim 1, a filter pond inflow line for supplying water to be treated to the filter pond, and a treatment subject to a filtration treatment in the filter pond. Measure the turbidity of the treated water sent from the filter pond to the filter pond outflow line, the filter pond outflow line that discharges the wash water that has washed the filter media in the filter pond, and the filter pond outflow line The treated water turbidity meter, the wash water turbidity meter that measures the turbidity of the wash water sent from the filter basin to the discharge line of the filter basin, and the filter media wash based on the measurement values sent from the treated water turbidity meter And a cleaning system control device for determining whether the system is activated or not, and determining whether the filter medium cleaning system is deactivated based on the measurement value sent from the cleaning water turbidity meter. Water treatment system.