JP3258583B2 - Membrane separation tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane separation device in which a large number of filtration membrane plates are provided in parallel, wherein the water to be treated is configured to be capable of solid-liquid separation. The present invention relates to a membrane separation tank provided with a water flow forming device for forming an upward flow of water to be treated.

[0002]

2. Description of the Related Art Heretofore, this kind of membrane separation tank has been constructed by simply providing a membrane separation device in a water treatment space containing water to be treated. In addition, a diffuser for supplying air bubbles to the membrane separator is usually provided below the membrane separator to form a water flow forming device for forming an upward flow of the water to be treated between the filtration membrane plates. is there. At this time, the ascending flow of the water to be formed formed between the filtration membrane plates is rapidly reduced when reaching the upper end of the membrane separation tank, and the flow of the water to be processed is stagnated, so that the membrane separation is performed. There is a problem in that the flow rate of the water to be treated in the tank is slowed down, and the efficiency of the water treatment is reduced because the stirring efficiency of the water to be treated is reduced. Attempts have been made to improve the efficiency of the system.
Therefore, in recent years, it has been proposed to provide a rectifying plate M6 in an inclined position above the membrane separation device, in which the flow direction of the water to be treated rises in the lateral direction (the direction along the water surface). (See Fig. 6)

[0003]

However, according to the above-mentioned conventional straightening vane, although the flow direction of the water to be treated when it reaches near the water surface can be directed in the horizontal direction,
Depending on the quality of the water to be treated, the flow of the water to be treated is often simply blocked or the flow of the water to be treated can hardly be changed. It was difficult to set an optimum inclination angle in accordance with the quality of the treated water, and it was practically difficult to use it.

[0004] Accordingly, an object of the present invention is to solve the above-mentioned drawbacks, and even when the water quality is variously different, the flow of the water to be treated is
An object of the present invention is to provide a membrane separation tank which is easily changed.

[0005]

A feature of the present invention to achieve this object is to provide a membrane separation device in which a large number of filtration membrane plates are provided in parallel, and to separate the water to be treated into solid and liquid. In the membrane separation tank provided with a water flow forming device that forms an upward flow of the water to be treated between the filtration membrane plates,
A rectifying plate is provided below the water surface above the membrane separation device, and the rectification plate is bent or curved to form a treated water having an inclination angle along the water surface more than the inclination angle on the membrane separation device side in a vertical front view. The guiding part is formed on the upper part of the rectifying plate, and the rectifying plate may have a plurality of plate-like bodies arranged in a line in the inclined direction, and the rectifying plate may be formed by the membrane separation tank. And a pair of right and left sides may be provided in a vertical front view, and it is preferable that the rectifying plate is swingably and detachably attached to the membrane separation device. A high effect can be obtained if the membrane separation tank has a circular front view, a vertically long oval, and a vertically long oval.

[Effects] That is, by providing the flow straightening plate as described above, it is possible to improve the treatment efficiency of the water to be treated by changing the flow of the water to be treated in the horizontal direction. At this time, depending on the quality of the to-be-processed water, it is conceivable that the water flow blows through in a direction along the surface of the rectifier plate and is not efficiently converted in the horizontal direction, or the water flow is stalled suddenly by the rectifier plate. However, the rectifying plate is formed to be bent or curved, and a to-be-processed water guiding portion having an inclination angle along a water surface more than an inclination angle on the membrane separation device side in a vertical front view is formed above the rectifying plate. First,
When reaching the lower part of the straightening plate, the water flow of the water to be treated gradually rises while being changed in the lateral direction by being guided to a relatively less inclined portion of the lower part of the straightening plate, and the water is guided to the treated water guiding part. And then converted into horizontal flow. For this reason, the flow can be smoothly guided regardless of the quality of the water to be treated, so that the flow can be changed in the lateral direction without significantly decreasing the flow velocity. (Refer to FIG. 2) As a result, the water to be treated circulates efficiently in the membrane separation tank and is treated with water, so that the water is efficiently treated and the water flow is easily maintained relatively quickly. It is difficult to form, and even if a precipitate is formed, it is easily dispersed in water by a water flow. Therefore, it is effectively treated, the inside of the tank is easily maintained in a healthy state, and the membrane separation is further efficiently performed.

In the case where a water flow is formed by air diffusion, air bubbles due to air diffusion move along the flow straightening plate.
The contact time with the water to be treated becomes longer, and the oxygen dissolving efficiency in the water to be treated is improved. Therefore, oxygen can be easily dissolved in the water to be treated, and even if the blower for aeration is of a small capacity, sufficient oxygen can be supplied. The running cost (electricity consumption) for operating the septic tank can be reduced.

It is preferable that a plurality of plate-like bodies are arranged side by side in the inclined direction, since a large rectifying action can be exhibited. Further, if the straightening plate is provided as a pair of right and left in a longitudinal sectional front view of the membrane separation tank, it is easy to form a uniform water flow in the membrane separation tank, and furthermore, the straightening plate is swingable to the membrane separation device and If it is detachably attached, even if the flow of the water to be treated is not optimally set in the initial setting, the setting can be changed, and there is an advantage that the flow of the water to be treated is easily adjusted, Even in the case of maintenance or the like, it is possible to easily cope with the necessity of removing the current plate. If the vertical front view is a circular, vertically long oval, or vertically long elliptical membrane separation tank, the water flow changed horizontally is converted downward along the side wall inside the tank, and an appropriate circulation flow Is easy to form, and is particularly effective in exhibiting a high effect.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the membrane separation tank of the present invention is used in one of the water treatment chambers of a septic tank. X1 and X2 are provided to form a closed space inside, and a plurality of water treatment spaces are provided inside and partitioned by providing a plurality of partition plates capable of forming a watertight partition. From the upstream side,
A flow control tank N, a denitrification tank E1, a membrane separation tank E2, and a discharge pump tank T are sequentially formed from the upstream side.
Is provided. Further, a manhole H used for maintenance and the like is provided at an upper portion of each of the tanks.

The flow rate adjusting tank N receives raw water to be treated flowing into the purification tank from an inlet I provided in one mirror portion X1 of the purification tank main body X, and removes impurities in the treatment water. By anaerobic bacteria growing inside while removing sediment,
A first pump P1 for transferring the water to be treated to the denitrification tank E1 is provided in the water treatment chamber for temporarily storing the water to be treated while performing the anaerobic treatment of the water to be treated, Even when there is no inflow of the water to be treated for a long period of time, the water to be treated is constantly transferred to the denitrification tank E1 so as not to hinder the water treatment in each of the subsequent water treatment chambers. In addition, relatively large impurities among the water to be treated flow into the flow rate adjusting tank N in a state where the impurities are separated into solid and liquid by the filtration screen F. Thereby, it is configured to be crushed and fragmented and flow into the flow rate adjusting tank N.

The denitrification tank E1 is connected to an inflow pipe A1 through which water to be treated from the flow rate adjusting tank N flows into the water treatment chamber adjacent to the flow rate adjusting tank N, to the first pump P1. To form an inflow passage for the water to be treated. In addition, a second pump P2 is provided therein, and the second pump P2 is provided with a transfer pipe A.
2 is provided to transfer the water to be treated to the membrane separation tank E2. In addition, a stirring pump P3 for stirring and circulating the water to be treated in the tank is provided to mix the water to be treated in the tank and mix the water to be treated with a high BOD load with the nitrified water to be treated. In addition, it is configured to perform advanced denitrification processing.

In the membrane separation tank E2, the inflow path is provided in a partition separating the denitrification tank E1, and the water to be treated excessively flowing from the denitrification tank E1 is supplied to the denitrification tank E1. A return port A4 for returning is provided to form a return path for the water to be treated. And, in the membrane separation tank E2,
A membrane separation device M is installed.

As shown in FIGS. 1 and 2, the membrane separator M
Is provided with a filtration membrane plate holding frame M2 for aligning and holding a large number of filtration membrane plates M1, a leg M3 for supporting the filtration membrane plate holding frame M2 is provided at a lower portion, and the filtration membrane between the legs M3. Board M
1 to prevent excessive adhesion of sludge and the like to the membrane surface and generate a circulating flow for forming an ascending flow of the water to be treated in the membrane separation tank E2. An air diffuser D which constitutes a water flow forming device for supplying oxygen to the air is internally provided. Further, an intake pipe M4 is connected to the filtration membrane plate M1 of the membrane separation device M, and the intake pipe M
A water collecting pipe M5 for connecting the filtered water from No. 4 to the outside of the membrane separation tank E2 and connecting the same to the discharge pump tank T adjacent to the membrane separation tank E2 below the water surface of the membrane separation tank E2. Connected.

As shown in FIGS. 2 and 3, a pair of straightening plates M6, each of which is a bent plate, is provided on an upper portion of the filtration membrane plate holding frame M2 so as to be swingable and detachable in a longitudinally frontal view of the septic tank. A to-be-treated water guiding portion M6a having an inclination angle along the water surface more than the inclination angle on the membrane separation device M side in a vertical front view is formed above the rectifying plate M6. Specifically, the lower part M6b of the bent plate is connected to the upper surface of the filtration membrane plate holding frame M2 at about 45 degrees, and formed so that the upper part of the bent plate is held substantially horizontally, The substantially horizontal upper portion forms a to-be-treated water guiding portion M6b. The pair of left and right bent plates are configured to swing in synchronization with each other so that the mounting angle can be balanced between the left and right sides. Incidentally, the mounting angle of such a rectifying plate M6 is set at a lower portion M6b of the bent plate.
Is 30 to 70 with respect to the upper surface of the filtration membrane plate holding frame M2.
It is desirable that the to-be-treated water guide part M6a be attached so as to be substantially horizontal.

According to such a configuration, the flow of the water to be treated is as shown in FIG. 2, and it is possible to prevent the water to be treated from stalling rapidly on the water surface. It has been found that the flow velocity of the downward flow of the water to be treated outside the membrane separation device can be set faster than the flow (see FIG. 6).

In addition, the dissolved oxygen concentration was examined in order to examine the oxygen dissolving efficiency in such a membrane separation tank.
It can be seen that oxygen is supplied more favorably than the membrane separation tank shown in FIG. By the way, the oxygen dissolution efficiency was also examined for a septic tank without a flow straightening plate.The oxygen dissolution efficiency at the bottom of the membrane separation tank was low, but the oxygen dissolution efficiency at the bottom was particularly improved. The formation of the flow also indicates that the dissolved oxygen is evenly distributed in the tank.

[0017]

[Table 1]

The filtered water storage tank T is connected to the membrane separation tank E2.
Tank that is equipped with a disinfection device Q1 equipped with a discharge pump P4 for storing the water to be transferred to be transported, and for transferring the water to be processed almost quantitatively, and a chemical disinfectant therein.
Is configured to be able to transfer the water to be treated.

The disinfecting tank Q is provided with a disinfecting device Q1 in which a disinfectant is provided in a container formed above the filtered water storage tank T, and the treated water transferred from the filtered water storage tank T is supplied to the disinfecting tank Q. The treatment water disinfected by the disinfection device Q1 is configured to be freely discharged to the outside, while being provided so as to be freely contacted with the disinfectant.

In general, chemicals for disinfecting water to be treated, including chemical disinfectants, are generally referred to as disinfectants.
As 1, an ultraviolet sterilizer or the like can be used.

[Another Embodiment] Another embodiment will be described below. In the above configuration, the straightening plate is constituted by a pair of right and left bent plates, but a curved plate may be used instead of the bent plate (see FIG. 4). Alternatively, the current plate may be configured by juxtaposing the inclination directions in parallel (FIG. 5).
reference).

The cross-sectional shape of the membrane separation tank is desirably a substantially circular shape such as a circle, an ellipse, and an ellipse, which can further convert the water flow converted in the horizontal direction downward. It is also possible to use those having a polygonal cross section such as a mold or a substantially square shape. In these cases, for example, the to-be-treated water guide portion M6a in FIG. 2 is preferably formed so as to be downward toward the front end, and formed in a shape capable of forming a downward flow of the to-be-treated water. The same effect as the inner mold of the membrane separation tank having a cross section such as a circle can be exhibited.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the accompanying drawings.

[Brief description of the drawings]

FIG. 1 is a vertical side view of a septic tank.

FIG. 2 is a vertical sectional front view of a membrane separation tank of a septic tank.

FIG. 3 is a schematic diagram of a main part of a membrane separation device showing a mounting structure of a current plate.

FIG. 4 is a longitudinal sectional front view of a membrane separation tank of a septic tank according to another embodiment.

FIG. 5 is a vertical sectional front view of a membrane separation tank of a septic tank according to another embodiment.

FIG. 6 is a longitudinal sectional front view of a membrane separation tank of a conventional septic tank.

[Explanation of symbols]

 M1 Filtration membrane plate M Membrane separation device D Air diffuser M6 Rectifier plate M6a Treatment water guide section

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shinichi Furuse 2 at Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture Inside Kubota Shiga Plant (56) References Hei 8-267082 (JP, A) JP-A Hei 8-47695 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01D 61/00-65/10 C02F 1/44 C02F 3 / 12

Claims (5)

(57) [Claims] 1. A membrane separation device (M) in which a number of filtration membrane plates (M1) are juxtaposed, wherein the water to be treated is configured to be capable of solid-liquid separation, and the filtration membrane plate (M1) is provided. A membrane separation tank provided with a water flow forming device (D) for forming an ascending flow of the water to be treated, wherein a flow straightening plate (M6) is provided below the water surface above the membrane separation device (M).
And the flow straightening plate (M6) is bent or curved to form a treatment water guiding portion (M6) having a tilt angle along the water surface more than a tilt angle on the membrane separation device (M6b) side in a vertical front view.
a) a membrane separation tank formed above the current plate (M6). 2. The membrane separation tank according to claim 1, wherein the rectifying plate (M6) is formed by arranging a plurality of plate-like bodies in parallel with each other in an inclined direction. 3. The membrane separation tank according to claim 1, wherein a pair of right and left flow straightening plates (M6) are provided in a longitudinal front view of the membrane separation tank. 4. The membrane separation tank according to claim 1, wherein the current plate (M6) is swingably and detachably attached to the membrane separation device. 5. The membrane separation tank according to claim 1, wherein a vertical front view is a circle, a vertically long oval, or a vertically long ellipse.