JP3548886B2 - Washing and regenerating method of filter media in filter - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for cleaning and regenerating a filter medium layer in a raw water filter including fine particles having a large specific gravity such as sand particles and metal fine particles.
[0002]
[Prior art]
Conventionally, a filter using a fiber filter medium is one that performs backwashing periodically during continuous operation when cleaning and regenerating clogged filter media, and also performs backwash cleaning by catching the filtration resistance (loss head) of the filter media. What you do is well known.
[0003]
[Problems to be solved by the invention]
However, in the conventional method as described above, when filtering inorganic contaminants having a high specific gravity, for example, raw water containing fine sand particles or metal particles, the filtration resistance is unlikely to increase. Captured above the value. If too much of this contaminant is captured, the filter device layer cannot be destroyed by the installed cleaning device, and cleaning becomes impossible or insufficient.
[0004]
[Means for Solving the Problems]
The present invention can solve the above-described problems, and the gist of the present invention is that in a raw water filter including fine particles having a large specific gravity such as sand particles, on the inflow side of the raw water of the filter, A flow meter that measures the inflow of raw water and a turbidity meter that measures the concentration of pollutants are provided.The detection signal is sent to the control panel of the filtration device, and a turbidity meter is provided on the filtrate extraction side of the filter. In addition to transmitting the detected concentration of contaminants in the filtered water to the control panel of the filtration device, integrating the raw water inflow amount received by the control panel and the pollutant concentration obtained by subtracting the concentration of the contaminants in the filtered water from the raw water pollutant concentration. Calculate the amount of contaminants and compare and calculate the total amount of contaminants for a predetermined period of time and the set value, and when the total amount of contaminants reaches the set value, send the command signal of the control panel as the filter medium capture limit value to the filter medium stirring and washing device. Send and wash the filter media layer of the filter Than it is.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
For the measurement of the integrated inflow amount, a normal flow meter is used, and a turbidity meter is provided downstream thereof, and its flow rate and concentration (turbidity) are transmitted to a control panel of a filter medium washing device, and the integrated inflow amount is measured. The amount of contaminants sent to the filter medium layer is determined, and when the amount of contaminants reaches a certain amount, the filtering operation is stopped based on the information and the filter medium is washed. Further, the accumulated pollutant amount is an amount that can be stirred in accordance with the capacity of the filter device washing device provided in the filter.
[0006]
As described above, according to the present invention, the contaminants flowing into the filter medium layer are washed when they reach a washable amount, so that it is possible to continue a stable filtration operation without making washing impossible or insufficient washing. it can. That is, compared to a conventional filter medium that periodically cleans the filter medium, the filter medium does not become uncleanable or insufficiently cleaned. And since the washing time of the filter medium is controlled by the amount of the contaminants flowing into the filter medium, even if the concentration of the contaminants in the raw water changes during the continuous operation, the filter medium can be washed and regenerated correspondingly. Hereinafter, the present invention will be specifically described with reference to the drawings.
[0007]
【Example】
FIG. 1 is a block diagram showing an operation flow of a filtration device according to the present invention. In the drawing, reference numeral 1 denotes a filtration machine in which a filter medium layer and a washing device are provided. On the raw water inflow side of the filter 1, an electromagnetic flow meter 2 for measuring the flow rate of the raw water as an instantaneous flow rate, and a turbidity meter 3 for measuring the instantaneous pollutant concentration are provided. The information is transmitted to the control panel 4. The control panel 4 receives a set value V derived in advance through experiments, and calculates a pollutant amount Q by integrating the raw water inflow amount a and the raw water contamination concentration b measured by the electromagnetic flow meter 2 and the turbidity meter 3. Then, the total amount of contaminants の Q for a predetermined time is compared with the set value V, and when the total amount of contaminants ΣQ reaches the set value V, the filter medium stirring and washing device is operated as a filter medium capture limit value. A turbidity meter 5 is provided on the filtrate extraction side of the filter 1 and transmits the detected concentration c of the contaminants in the filtered water to the control panel 4 of the filtration device to convert the raw water contamination concentration b into the filtered water. If the pollutant concentration (bc) is obtained by subtracting the pollutant concentration c, the pollutant concentration Q ′ is calculated by integrating the raw water inflow a received by the control panel 4 and the pollutant concentration (bc). If the total amount of contaminants ΣQ 'reaches the set value V' when the total amount of contaminants ΣQ 'reaches the set value V' at any time, the total amount of contaminants ΣQ 'can be grasped more accurately. By transmitting a command signal of the control panel 4 as a value to the filter medium stirring and washing apparatus, the filter medium layer of the filter 1 can be washed. The broken arrow lines indicate the connection state. An arrow A indicates an inflow line of raw water, an arrow B indicates an extraction line of treated water, an arrow C indicates an inflow line of cleaning water, and an arrow D indicates an extraction line of cleaning wastewater.
[0008]
In the above operation flow diagram, raw water is sent to the filter 1 via the electromagnetic flow meter 2 and the turbidity meter 3 and filtered, and then the treated water is taken out of the system via the turbidity meter 5. On the other hand, the electromagnetic flow meter 2 measures the inflow of raw water, and the measured value is transmitted to the control panel 4 as information. The turbidity meter 3 measures the turbidity of the inflowing raw water and transmits the measured value to the control panel 4 as information. The control panel 4 calculates the integrated pollutant amount flowing into the filter medium layer from the inflow amount information of the raw water and the turbidity concentration information thereof.
[0009]
Then, when the filtration operation as described above is continued and the inflow of raw water (the amount of pollutants) into the filter 1 reaches a certain value, the supply of the raw water is stopped, the filter cleaning device is activated, and the filter is stirred. Washed. That is, in the present invention, the degree of clogging of the filter medium layer is determined based on the accumulated inflow amount of raw water, and the filter medium is agitated and washed at an appropriate time, thereby preventing washing from being impossible or insufficient washing.
[0010]
The amount Q of contaminants sent to the filter medium layer is calculated based on the raw water contamination concentration b and the raw water inflow amount a. The pollutant inflow limit as to whether or not the clogged filter medium layer can be stirred and washed. The amount is determined based on experimental values based on the properties of raw water and the properties of the filter medium.
[0011]
Conventionally, if the filter media is washed with a filter using this type of granular filter media simply at regular time intervals, the degree of clogging of the filter media layer differs depending on the amount of contaminants in the raw water. Since cleaning is performed without consideration, cleaning is often impossible or insufficient. That is, when the pollutant has a large inorganic specific gravity, the trapped pollutant accumulates in the filter medium layer, solidifying the filter medium layer, making it impossible to wash or insufficient washing. In addition, even when the filter head is washed by detecting the head loss due to the filter medium, if the contaminants accumulate and the filter medium layer is closed, the stirring cannot be performed, and the washing cannot be performed. In such a case, in the present invention, the washing is performed based on the amount of contaminants trapped in the filter medium layer, so that the above-described difficulties can be solved and a stable filtration operation can be performed.
[0012]
【The invention's effect】
As described above, according to the method according to the present invention, as is apparent from the above description, according to the method for cleaning and regenerating a filter medium of the present invention, a filter medium layer of a filter machine in which a filter medium capture limit value can be predicted and clogged is cleaned. You can do it. That is, in the conventional cleaning method, even if a large amount of a substance having a high specific gravity contained in the stock solution is captured in a large amount in the filter medium gap, the filtration resistance does not increase, making it difficult to determine the cleaning time, causing insufficient cleaning or cleaning. However, according to the present invention , a flow meter and a turbidity meter are provided on the raw water inflow side, and the detection signal is transmitted to the control panel of the filtration device. If a turbidity meter is installed on the liquid extraction side and the concentration of contaminants in the filtered water is sent to the control panel of the filtration device, the filter media capture limit can be accurately determined based on the amount of raw water inflow, the raw water contamination concentration, and the concentration of contaminants in the filtered water. The value can be grasped, and the filter medium layer of the filter can be automatically cleaned by the stirring and cleaning device.
[Brief description of the drawings]
FIG. 1 is an operation flowchart of a filtration operation by a filter according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Filtration machine 2 Electromagnetic flow meter 3 Turbidity meter 4 Control panel 5 Turbidity meter a Raw water inflow b Raw water contamination concentration c Concentration of contaminants in filtered water bc Contamination concentration Q, Q 'Contamination amount ΣQ Contamination amount 物 Q 'Total amount of pollutants V, V' Set value

Claims (1)

A filter 1 for forming a compressible filter medium layer with a fiber filter medium and filtering raw water containing fine particles having a large specific gravity, such as sand particles, on a raw water inflow side of the filter 1 for measuring a flow rate of raw water. 2 and a turbidity meter 3 for measuring the pollutant concentration are provided, and the detection signal is transmitted to the control panel 4 of the filtration device, and a turbidity meter 5 is provided on the side of the filtrater 1 from which the filtrate is taken out. The concentration c of the contaminants in the water is sent to the control panel 4 of the filtration device, and the concentration c of the contaminants in the filtered water is subtracted from the inflow amount a of the raw water and the raw water contamination concentration b received by the control panel 4. −c) is integrated to calculate a pollutant amount Q ′, and, at any time, a comparison operation of the total pollutant amount ΣQ ′ for a predetermined time and the set value V ′, and when the total pollutant amount ΣQ ′ reaches the set value V ′ , The command signal of the control panel 4 is transmitted to the filter medium stirring and washing device as the filter medium capture limit value, and the filter medium layer of the filter 1 is removed. Cleaning regeneration method of the filter material in the filter machine to Kiyoshi.

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