JP2940364B2 - Cleaning method of filter media in filter using floating media - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention, washing relates to an improved method for cleaning filter medium in the filtration apparatus using a filter media lightweight particulate, such as polystyrene foam, without stopping the supply of raw water, a short time filter material It is intended to provide a renewable cleaning method.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 63-185 discloses a method for cleaning a filter medium of this kind in a conventional filter using a floating filter medium.
No. 416. In this product, in order to wash the clogged filter media, after stopping the supply of raw water and mechanically stirring the filter media to loosen the filter media, drain some of the wastewater,
Next, after supplying the raw water into the tank and stirring it again, the waste water is discharged.

[0003]

That is, in the above-described conventional apparatus, when the filter medium is washed, the supply of the stock solution is stopped to wash a part of the filter medium, and then the stock solution is supplied to remove the entire filter medium. The washing is performed, and it takes a long time to perform the agitation washing twice, and it takes a long time to discharge the washing sewage and to inject the raw water for restarting the operation. And
During this time, all of the filtration operations must be stopped.

[0004]

SUMMARY OF THE INVENTION The present invention has been achieved by solving the above-mentioned conventional problems by using the following method. The gist of the present invention is that the particles float in a closed tank. Filling the filter media, providing a nozzle for removing the filtrate at the top of the closed tank, and an upward flow filter of raw water provided with a discharge outlet for washing and draining the filter media at the lower bottom,
Upon cleaning the clogged filter material, the raw water clogging the filter medium while supplying allowed to stir distributing, after the separated water has been drained Nozzle or al, is ejected or al raw Nozzle in filter media, washing the filter medium The sewage is taken out from the outlet at the bottom of the closed tank. V1 to V5 indicate valves respectively provided in the above-mentioned respective pipelines.

[0005]

According to the method of the present invention, since the raw water is used as the washing water for cleaning the filter medium, the supply of the raw water into the tank is not interrupted during the cleaning. This is to discharge only the wastewater containing impurities while rinsing the filter medium washed and washed.During this time, the inside of the tank is not emptied. Can be. That is, the filter medium can be washed in a much shorter time as compared with the case where the inside of the tank is emptied twice, while there is concern about the outflow of the conventional filter medium. Below, based on the figure,
The present invention will be specifically described.

[0006]

In FIG. 1, reference numeral 1 denotes a closed tank, 2 denotes a partition plate, 3 denotes a water collecting nozzle mounted on the partition plate 2, 4 denotes a floating filter medium layer, 5 denotes a reservoir for filtrate, and 6a denotes a pipe for taking out filtrate. , 6b is a waste water pipe, 7 is a pit that serves both for supplying raw water and discharging sewage,
7a is a supply pipe of raw water, 7b is a discharge pipe of sewage, 7c is a supply pipe of raw water for backwashing, and 8 is a stirring blade of a filter medium. Note that the symbol V
Numerals 1 to V5 denote valves provided in each of the above-mentioned conduits.

In the filter constructed as described above, filtration and washing of the filter medium are performed as follows. That is, in the case of the filtration operation, the raw water from the supply pipe 10 is supplied to the valve V
2. It is sent to the closed tank 1 through the supply pipe 7a and the pit 7. Then, while ascending in the filter medium layer 4, the contained contaminants are captured, and the filtrate is taken out of the take-out pipe 6a via the water collecting nozzle 3 and the valve V4 .

When the filter medium is clogged by the above-described filtration operation, the valve V4 is closed and the valve V5 is opened to rotate the stirring blade 8 while the supply of raw water is continued from the valve V2. The filter material is dispersed by the stirring blades 8 to separate impurities, and only the separated water can be discharged to the outside of the apparatus via the valve V5.

[0009] Next, to stop the stirring blades 8, closing the valve V2, sealing and opening the valve V1 tank 1
Inside, the filter medium from which the impurities are separated floats up to form a filter medium layer (filtration layer). The time for the filter medium to float and form the filter medium layer in the closed tank 1 is extremely short as compared with the conventional time for draining the wastewater from the tank. After separating the impurities in the filter medium layer as described above, the valve V5
Is closed and the valve V3 is opened, so that the raw water that has passed through the valve V1 flows into the filter medium layer 4 from the nozzle 3 (backflow), and at the same time, the filter medium layer 4 is rinsed, and at the same time, outside the machine via the pit 7 and the valve V3 The contaminants that have flowed out and settled at the bottom of the closed tank 1 such as the pit 7 can be discharged. After discharging the impurities, the valve V1 is closed,
By opening valve V2 and valve V4,
Raw water rises in the closed tank 1 and removes the filtered water from the discharge pipe 6.
a.

That is, the present invention is characterized in that the filter medium from which impurities are separated is rinsed with raw water, and at the same time, the separated impurities are washed out by raw water and discharged, and during this time, the inside of the closed tank is emptied. Thus, the time required for filtration can be greatly reduced as compared with the conventional method for washing a filter medium.

FIG. 2 shows the operating states of the valves and the stirring blades during the above-mentioned filtering operation and the washing of the filter medium.
During cleaning and regeneration ( when valve V3 or V5 is open)
1 or the valve V2 is open, indicating that raw water is supplied into the closed tank 1 and the inside of the closed tank is not emptied, and that the operation immediately proceeds to the next filtration operation only by operating the valve.

[0012]

As is apparent from the above description, according to the present invention, in a filter using a floating filter medium, when the filter medium is clogged, the filter medium can be washed and regenerated without draining the raw water in the filtration tank. , When this kind of conventional filter is used to wash the filter media,
This completely eliminates the time of draining and supplying the raw water in the tank and increasing the operation rate of this type of filter. It is effective.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional side view of a filtration device using a floating filter medium used in the present invention.

FIG. 2 is a table showing operating states of valves and stirring blades used in each part when the filter according to the present invention is operated.

[Explanation of symbols]

 1 Closed tank 3 Nozzle

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-220305 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B01D 29/00-29/96

Claims (1)

(57) [Claims] 1. A closed floating tank 1 is filled with a granular floating filter medium, a nozzle 3 for removing a filtrate is provided at the top of the closed tank 1, and an outlet 7 for washing and draining the filter medium is provided at a lower bottom thereof. In the upward flow filter of the raw water, when the clogged filter medium is washed, the clogged filter medium is stirred and dispersed while supplying the raw water, the separated water is drained from the nozzle 3, and then the raw water is discharged from the nozzle 3 into the filter medium. A method of cleaning a filter medium using a floating filter medium, characterized in that sewage which has been ejected to the filter medium and which has washed the filter medium is taken out from the lower bottom of the closed tank 1.