JP2553911Y2 - Sewage septic tank - Google Patents

Description

[Detailed description of the invention]

[0001]

This invention comprises an aerobic treatment tank such as an anaerobic filter tank or a sedimentation separation tank, a contact aeration tank or an activated sludge tank, and a disinfecting tank. The present invention relates to a sewage purification tank provided with a membrane module for sucking and separating water.

[0002]

2. Description of the Related Art Conventionally, sewage purification tanks such as merged purification tanks have been provided with anaerobic filter tanks or sedimentation separation tanks, aerobic treatment tanks such as contact aeration tanks and activated sludge tanks, and disinfection tanks. While purifying by biological action is known. Also, as shown in FIGS. 2 and 3, a membrane module B made of a microporous membrane made of a ceramic material or the like is provided in an aerobic treatment tank (in the illustrated example, a contact tank), and the membrane module B is passed through a suction pump C. There is also known a suction type membrane separation type sewage purifying tank which separates treated water by suction and sends it to a disinfection tank D or the like.

[0003]

However, in the above-mentioned suction type membrane separation type sewage treatment tank, since the membrane module B is clogged with the suction filtration of the treated water, air is periodically sent into the membrane module B. Washing (so-called backwashing) has to be performed frequently, and there is a disadvantage in that the installation of the backwashing device and its power unit is expensive.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide a sewage purifying tank which does not require power or minimizes the efficiency of backwashing of a membrane module. It was done.

[0005]

That is, the sewage purification tank of the present invention comprises an anaerobic filter bed tank or a sedimentation separation tank, an aerobic treatment tank and a disinfection tank, and a membrane for suctioning and separating treated water in the aerobic treatment tank. Module and a suction pump for sucking the treated water through the membrane module, and a filtration water tank for securing the water level at a position higher than the water level in the aeration tank in contact with the disinfecting tank is connected to the suction pump. And a pipe for pumping the suction treatment water from the filter water tank to the filtration water tank, and the filtration water tank is configured to overflow the treatment water into the disinfection tank.

[0006]

Next, an embodiment of the present invention will be described. FIG. 1 is a sectional view of an embodiment of the present invention. That is, the sewage purification tank 1 of this invention is an anaerobic filter first chamber 1 as an anaerobic filter tank.
A, the second chamber 1B, the contact aeration tank 1C and the disinfection tank 1D
The contact aeration tank 1C as an aerobic treatment tank is equipped with a diffuser pipe 2 for supplying air for diffusing air to the sludge in the tank, and a height position at which the liquid in the contact aeration tank 1C can be sucked. A membrane module that suction-separates the treated water in the tank, for example, a ceramic membrane, or glass or plastic.
A membrane module 3 such as a separation membrane module comprising a microporous tube having an opening of 1 to 60 μm and a suction pump 4 for sucking the processing solution in the tank through the membrane module 3 are provided, and are brought into contact with the disinfection tank 1D. A filtration water tank 1E for securing a water level higher than the water level of the air tank 1C is attached, and the processing liquid sucked by the suction pump 4 is filtered water tank 1E.
A pipe 5 is formed so as to pump water, and the pumped processing liquid overflows from the filtration water tank 1E to the disinfection tank 1D. In addition, although the case of the contact aeration tank 1C as the aerobic treatment tank is shown in the above embodiment, the present invention can be similarly applied to an activated sludge treatment tank. In this case, the membrane module 3 is provided at the height of the supernatant of the treated water in the tank.

[0007]

According to the above-mentioned sewage purification tank 1, the treatment liquid in which organic components and the like are decomposed is suction-filtered by the membrane module 3, pumped to the filtration water tank 1E by the suction pump 4, and then overflowed to the disinfection tank 1E. It is discharged outside the sewage purification tank 1. In that case, when the suction pump 4 is stopped, the filtration water tank 1 is stopped.
Since E is provided at a position higher than the water level of the contact aeration tank 1C, the head pressure of the water level of the filtration water tank 1E is applied to the inner surface of the membrane module 3, and conversely, the suction inside the membrane module 3 and the suction pump 4 is performed. The supernatant liquid flows out of the membrane module 3, and the sludge attached to the membrane surface of the membrane module 3 is peeled off, and the membrane module 3 is washed. At this time, the air outlet 2a of the air diffuser 2 is connected to the membrane module 3
If the air is blown out from the air blow-out port 2a in advance, the air hits the membrane module 3 and the separation of the membrane sludge is further promoted.

[0008]

As is clear from the above description, according to this invention, the treated water once drawn into the membrane module flows out of the membrane module by stopping the suction pump and utilizing the head pressure of the filtration tank. The cleaning of the membrane module can be performed in this way, making the equipment simpler than conventional cleaning with air, eliminating the need for a special power unit, reducing the power for backwashing, and reducing operating time. As a result, the power consumption can be reduced, and a practical effect of providing an inexpensive membrane separation type sewage treatment tank can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a conventional example.

FIG. 3 is a longitudinal sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sewage purification tank 1A Anaerobic filter tank first room 1B Anaerobic filter tank second room 1C Contact aeration tank 1D Disinfection tank 1E Filtration water tank 3 Membrane module 4 Suction pump

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor: Dai Harada 2 at Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture Inside the Kubota Shiga Plant. 1 Kubota Shiga Factory (56) References JP-A-61-249599 (JP, A)

Claims (1)

(57) [Scope of request for utility model registration] 1. A membrane module comprising an anaerobic filter tank or sedimentation separation tank, an aerobic treatment tank and a disinfecting tank, and a suction module for sucking and separating treated water in the aerobic treatment tank, and a suction for sucking treated water through the membrane module. A pump is provided, and a filtration water tank that secures a water level at a position higher than a water level in the aeration tank in contact with the disinfection tank is provided in series, and a pipe for pumping suction-treated water from the suction pump to the filtration water tank is provided. A sewage purification tank provided, wherein the filtration water tank is configured to overflow treated water into the disinfection tank.