JPH08920A - Multistage filter - Google Patents

Abstract

PURPOSE:To provide a multistage filter decreased in cost, enhanced in filtering efficiency, reduced in the use amt. of a rinse soln. and capable of preventing the deviation of a flow rate (deflected flow) to each of filter chambers. CONSTITUTION:At the time of filtering (1), a liquid containing a solid is passed through the filter parts 2a, 2b of upper and lower stage filter chambers A, B downwardly through liquid injection pipings 4, 4a to collect the solid in the liquid while a filtrate is discharged out of a container 1 from liquid discharge pipings 5b, 5a and opening and closing valves 16 to 26 are appropriately operated to pass the liquid through one of the upper and lower stage filter chambers A, B or both of them in succession to perform filtering work. At the time of the backwashing of the filter parts 2a, 2b (2), a washing soln. is passed through the filter parts upwardly and the collected solid is removed to the outside of the container along with the washing soln. At the time of the rinsing work of the filter parts 2a, 2b (3), a rinse soln. is sent to the upper and lower stage filter chambers A, B from the liquid injection pipings 4, 4a and passed through the filter parts 2a, 2b downwardly to condition the filter parts 2a, 2b and discharged out of the container 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure sand filter for water treatment, an activated carbon tower, a limestone packed tower for drinking water (mineralization) of water, and the like.

[0002]

2. Description of the Related Art A conventional filter has a column diameter of about 5 m at the maximum because of transportation restrictions and, in the case of a pressure vessel, economical efficiency for pressure resistance design. If more than that, a plurality of filters are installed. A conventional example will be described with reference to FIG. 4. 11a and 11b are containers (filter main body), and 12a and 12b are containers 11a and 11b.
Inside, a filtration part, 14, 14a, 14b are liquid injection pipes communicating with the upper part of the container 11, 15a, 15b, 15 are liquid discharge pipes communicating with lower parts of the containers 11a, 11b, 13
a and 13b are rinse discharge pipes communicating with the liquid discharge pipes 15a and 15b, and 30a and 30b are liquid discharge pipes 15
The backwashing injection pipes communicate with a and 15b, and the backwashing discharge pipes 31a and 31b communicate with the liquid injection pipes 14a and 14b.

In this filter, a liquid (stock solution) containing a solid material is filled with liquid injection pipes 14, 14a, 14b → container 11
a, 11b, and passed through the filtration sections 12a, 12b in the containers 11a, 11b to collect and remove the solid matter in the liquid by the filtration sections 12a, 12b, while removing the solid matter. The filtrate is supplied to the liquid discharge pipes 15a, 15b, 1
5 is discharged to the outside of the containers 11a and 11b.

At the time of the above filtration, the solid matter is filtered by the filtration unit 12.
Since it collects in a and 12b, the cleaning liquid such as water is flowed to the backwashing injection pipes 30a and 30b → the filtration parts 12a and 12b in the containers 11a and 11b → the backwashing discharge pipes 31a and 31b depending on the time, and the filtration part The solid matter collected by 12a and 12b is washed with the washing liquid from the backwash discharge pipes 31a and 31b to the container 11
Remove to the outside of a and 11b.

At this time, the filter layers (for example, sand particle layers) of the filter sections 12a and 12b are disturbed in the layer state by the above-mentioned backwashing. Therefore, after the backwashing, rinse liquid such as water is injected into the liquid injecting pipes 14 and 14a. 14b → filter sections 12a, 12b in the containers 11a, 11b → circulate to the rinse discharge pipes 13a, 13b to adjust the filter layers (for example, sand particle layers) of the filter sections 12a, 12b to the original state.

[0006]

The conventional filter shown in FIG. 4 has the following problems. That is, (1) When increasing the filtration area, the number of filters must be increased or a gravity type filter using a concrete water tank (a type of filter in which water flows downward due to its own weight) must be adopted. In the case of, however, in the case of, the maximum filtration area per unit is limited due to transportation restrictions, and if the filtration area is increased, the number of installed filters increases. When the number of installed filters is increased, the number of pipes and valves is increased, and the installation area of the entire filter is increased, resulting in high cost.

In the case of the above, the water flow rate is slow, and in order to compensate for this, it is necessary to increase the filtration area, and the size of the entire filter becomes large, and in this case also the cost becomes high. (2) If the filter is, for example, a pressurized sand filter that performs water treatment, it is necessary to perform backwashing once a day. Further, after backwashing, it is necessary to pass the rinse liquid at a rate of about 1 hour per filter unit in order to adjust the filtration layer (for example, sand particle layer) of the filtration unit 12 to the original state,
During that time, there was a problem that the original filtration treatment could not be performed, the filtration efficiency was lowered, and a large amount of rinse liquid was required.

The present invention has been proposed in view of the above problems, and the object of the present invention is to reduce the cost.
The filtration efficiency can be improved, the amount of rinse liquid used can be reduced,
The point is to provide a multi-stage filter that can prevent uneven flow (uneven flow) to each filtration chamber.

[0009]

In order to achieve the above-mentioned object, the present invention is a filter for removing solids mixed in a liquid, wherein the inside of the container is divided into a plurality of parts in the vertical direction and a plurality of stages of filtration are provided. A partition plate that constitutes a chamber, a filtration unit in each of the filtration chambers, a liquid injection pipe that communicates with the upper portion of each of the filtration chambers,
A liquid discharge pipe communicating with a lower portion of each of the filtration chambers, and a plurality of liquid injection pipes and a plurality of opening / closing valves provided in the liquid discharge pipes are provided. It is characterized in that each of the filtration chambers is circulated alone or in the order from the upper filtration chamber to the lower filtration chamber.

In the multistage filter, each liquid injection pipe may be provided with a dispersion orifice. In the multistage filter, a flow control valve may be provided in each liquid injection pipe.

[0011]

The multistage filter of the present invention is configured as described above, and (1) at the time of liquid filtration, a liquid (stock solution) containing a solid is filtered from the liquid injection pipe to the upper filtration chamber and the lower filtration chamber. While the solids in the liquid are collected and removed by these filtration units by passing the portion downward, the filtrate after the solids are removed is discharged from the liquid discharge pipe to the outside of the container. At this time, each on-off valve is appropriately operated to allow the liquid to flow in the upper filtration chamber, the lower filtration chamber alone, or in the order from the upper filtration chamber to the lower filtration chamber to perform the filtering operation. (2) At the time of back-flow cleaning of each filtering unit, the cleaning liquid is caused to flow upward through each of the filtering units, and the solid matter collected by each filtering unit is removed from the container together with the cleaning liquid. (3) During the rinsing operation of each filtration section, the rinse liquid is sent to the liquid injection pipe → the filtration section of the upper filtration chamber → the filtration section of the lower filtration chamber, and the filtration sections are passed downward to pass the filtration sections. After preparing, discharge it out of the container. Even during the above-described backflow cleaning work and rinse work, the respective on-off valves are appropriately operated to perform the respective works.

[0012]

EXAMPLES Next, a multistage filter of the present invention will be described with reference to an embodiment shown in FIGS. 1 and 2. 1 is a container (multistage filter main body), and 7 is a plurality of containers in a vertical direction in the container 1 ( In case of figure 2
Partition walls which form the filtration chambers A and B by dividing into two), 6 is a concrete layer formed on the upper surface of the partition plate 2, 2a and 2b are the filtration parts 4, 4a and 4b in the filtration chambers A and B. Filtration chamber A,
Liquid injection pipes 5a, 5b, 5 communicating with the upper part of B are liquid discharge pipes communicating with the lower parts of the filtration chambers A, B.

30a and 30b are liquid discharge pipes 5a and 5
b is a backwash injection pipe, 31a and 31b are backwash discharge pipes provided in the liquid injection pipes 4a and 4b, and 3a is a rinse discharge pipe that communicates the liquid discharge pipe 5a with the upper part of the filtration chamber B,
Rinse discharge pipe 3b communicating with liquid discharge pipe 5b, 2
8 is a coagulant supply pipe communicating with the rinse discharge pipe 3a, 27
Reference numerals a and 27b are dispersion orifices (or flow control valves) provided in the liquid injection pipes 4a and 4b.

Electromagnetic on-off valves 16 to 26 are provided on the pipes and pipes. These electromagnetic on-off valves 16 to 26 are turned on and off at appropriate times by a timer so that the pipes and pipes can be opened and closed. Has become. The above-mentioned filter is of a multi-stage type, and it is expected that the flow rate to the filtration chambers A and B will be biased (unbalanced flow). ) 27a,
27b is provided to prevent this drift.

Further, when the container 1 is a pressure container, a normal partition plate is curved in a semi-elliptical shape in cross section as shown in FIG. 3 (see reference numeral 9) from the viewpoint of strength, and the space between the partition plate and the side wall of the container. A stagnant portion 8 is formed at the end, and corrosion easily occurs. This retention section 8
Since it is difficult to apply the lining, the concrete layer 6 is formed on the upper surface of the partition plate 7 to prevent corrosion, as shown in FIG. When the partition plate is curved as shown in FIG. 3B, the container may be installed by inverting the container after forming the concrete layer 6.

Next, the operation of the multistage filter shown in FIGS. 1 and 2 will be specifically described. (1) At the time of filtering the liquid (stock solution), the liquid containing the solid matter (stock solution) is sent to the liquid injection pipe 4 → the liquid injection pipe 4a → the filtration chamber A of the container 1 → the filtration unit 2a and passes through the filtration unit 2a. Then, while the solid matter in the liquid is collected and removed by the filtration unit 2a, the filtrate after removing the solid matter is discharged from the liquid discharge pipe 5a to the liquid discharge pipe 5 to the outside of the container 1.

Further, a liquid (stock solution) containing solid matter is sent to the liquid injecting pipe 4 → the liquid injecting pipe 4b → the filtering chamber B of the container 1 → the filtering part 2b, and is passed through the filtering part 2b to obtain the solid in the liquid. The filtration unit 2b collects and removes the substance, and the filtrate after removing the solid matter is discharged from the liquid discharge pipe 5b to the liquid discharge pipe 5 to the outside of the container 1. At that time, the solenoid valve 1
By appropriately operating 6 to 26, the liquid is circulated in the order of the filtration chambers A and B alone or from the upper filtration chamber A to the lower filtration chamber B. (2) During backwashing of the filtration units 2a and 2b, the cleaning liquid is circulated to the backwash injection pipe 30a, the filtration chamber A of the container 1, the filtration unit 2a, the liquid injection pipe 4a, and the backwash discharge pipe 31a. The solids collected by 2a are removed to the outside of the container 1 together with the cleaning liquid, while the cleaning liquid is circulated to the backwash injection pipe 30b → the filtration chamber B of the container 1 → the filtering part 2b → the liquid injection pipe 4b → the backwash discharge pipe 31b. Then, the solid matter collected by the filtration unit 2b is removed to the outside of the container 1 together with the cleaning liquid. In that case,
The backflow cleaning work is performed by appropriately operating the electromagnetic on-off valves 16 to 26. (3) At the time of rinsing the filtration units 2a and 2b, the rinse liquid is sent to the liquid injection pipe 4 → the liquid injection pipe 4a → the filtration chamber A of the container 1 → the filtration unit 2a, and passes through the filtration unit 2a,
After arranging the filtering part 2a, the rinsing liquid is discharged to the liquid discharging pipe 5a, while the rinse liquid is sent to the rinsing discharging pipe 3a → the filtering chamber B of the container 1 → the filtering part 2b, and passes through the filtering part 2b. After preparing 2b, the liquid is discharged from the liquid discharge pipe 5b to the rinse discharge pipe 3b to the outside of the container 1. Also at that time, the above-mentioned rinse work is performed by appropriately operating the electromagnetic opening / closing valves 16 to 26.

[0018]

INDUSTRIAL APPLICABILITY The present invention has a multi-stage filter chamber as described above, and if one multi-stage filter is installed,
Since a plurality of conventional filters are installed, the number of installed filters can be reduced. Further, along with this, it is possible to reduce the number of pipes and valves, and it is possible to reduce the installation area of the entire filter, and it is possible to reduce the cost.

Further, after backwashing, it is necessary to pass the rinse liquid through the filter at a rate of about 1 hour in order to restore the original state of the filter layer (eg, sand particle layer) in the filter section.
In the multi-stage filter of the present invention, since the rinse liquid is circulated in the order of the upper filtration chamber and the lower filtration chamber, the rinsing work for a plurality of filters can be completed in about 1 hour (the rinsing work time of the entire filtration device As a result, the filtration time of the liquid containing the solid matter can be lengthened and the filtration efficiency can be improved.

Further, since the rinse liquid is circulated in the order from the upper filtration chamber to the lower filtration chamber, that is, the rinse liquid used in the upper filtration chamber is reused in the lower filtration chamber, the amount of rinse liquid used can be reduced. Further, since the amount of rinse liquid used can be reduced as described above, the capacities of the backflow cleaning pump and the blower can be reduced, and the cost can be reduced in this respect as well.

Further, since the filter is of a multi-stage type and the flow rate to each filtration chamber is expected to be biased (unbalanced flow), a distribution orifice (or a flow control valve) is provided in each liquid injection pipe to each filtration chamber. Is provided to prevent this drift.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of a multistage filter of the present invention.

FIG. 2 is a vertical cross-sectional side view showing details of a partition plate of the multi-stage filter.

FIG. 3A is an explanatory diagram showing a retaining portion of a partition plate curved upward, and FIG. 3B is an explanatory diagram showing a retaining portion of a partition plate curved downward.

FIG. 4 is a system diagram showing a conventional filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container (filter main body) 2a Filtration part in filtration chamber A 2b Filtration part in filtration chamber B 4, 4a, 4b Liquid injection pipe 5, 5a, 5b Liquid discharge pipe 7 Partition plate 16-26 Open / close valve A Upper filtration chamber B Lower filtration chamber

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location C02F 1/28 F B01D 29/08 540 A 29/42 510

Claims (3)

[Claims] 1. A filter for removing solid matter mixed in a liquid, wherein the inside of the container is vertically divided into a plurality of partitions to form a plurality of stages of filtration chambers, and a filtration section in each of the filtration chambers. A liquid injection pipe communicating with the upper part of each of the filtration chambers,
A liquid discharge pipe communicating with a lower portion of each of the filtration chambers, and a plurality of liquid injection pipes and a plurality of opening / closing valves provided in the liquid discharge pipes are provided. A multistage filter characterized in that each of the filtration chambers is allowed to flow independently or in the order from the upper filtration chamber to the lower filtration chamber. 2. The multi-stage filter according to claim 1, wherein each liquid injection pipe is provided with a dispersion orifice. 3. The multi-stage filter according to claim 1, wherein a flow rate control valve is provided in each of the liquid injection pipes.