JPH0777A - Cleaning device for closed water system - Google Patents

Abstract

PURPOSE:To provide the subject device where clean water is always circulted in the tank to make it unnecessary to exchange water with increased water- saving effect, and the membrane modules are always washed with the ascending stream to suppress the reduction in the permeation volume thereby the maintenance is in no need for a long period of time. CONSTITUTION:The water tank 1 is separated with the overflowing wall 14 to prepare the partition for the water to be filtered 13 and a plurality of membrane modules 17 are set in the partition 13 and an aeration unit 18 is arranged under the modules 17 and a suction pump is provided on the way of the suction pipe 20 connecting the path for the permeating flow in the module 17 to the other partition 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a purifying device for a closed water system such as a water tank, a bathtub, a fountain facility, and a reservoir.

[0002]

2. Description of the Related Art Conventionally, in a closed water system such as a water tank 1 or a reservoir as shown in FIG. 2, water in the water tank 1 is circulated by a pump 3 in an extra filtration device 2 installed outside the water tank 1. ,
The filter material of the out-of-tank filtration device 2 filters out contaminant source substances such as algae and fish dung. Alternatively, the in-tank filtering device 4 is immersed in the water tank 1, and the water in the in-tank filtering device 4 is discharged to the outside of the device by the air lift action of the air.
The water inside is taken into the device through the filtering material of the in-tank filtering device 4, and the contaminants such as algae and fish dung are filtered and removed by the filtering material.

[0003]

However, in the above-mentioned conventional structure, it is necessary to periodically replace or wash the filter material of the out-tank filtration device 2 or the in-tank filtration device 4. In addition, it is difficult to remove nitrogen and phosphorus dissolved in water, and it is possible to suppress algae growth due to nitrogen and phosphorus.
There was a problem that algae adhered to the glass walls of the above and hindered viewing. Furthermore, it is impossible to remove pathogenic bacteria such as Escherichia coli, and there is a problem that fishes get sick. Further, there is a problem that organic matter is eluted from the food, fish droppings, etc. attached to the filter medium, and the water in the aquarium 1 is contaminated.

The present invention solves the above problems and provides a purification apparatus for a closed water system, which removes nitrogen and phosphorus in the closed water system to prevent algae from growing and requires no maintenance for a long period of time. The purpose is to

[0005]

In order to solve the above-mentioned problems, a purifying apparatus for a closed water system according to the present invention is an overflow in which an inner space is divided into a water tank section and a filtration raw water tank section in a water tank forming a closed water system. A weir is provided, and a plurality of membrane modules are immersed in the filtration raw water tank in parallel so as to form a vertical flow path between the membrane modules, and an air diffuser is arranged below the membrane module. The suction pump is provided in the middle of the suction pipe that connects the permeate passage in the membrane module and the water tank.

[0006]

With the above-described structure, the water in the water tank portion flows over the overflow weir and flows into the raw filtration water tank portion. The water in the filtered raw water tank portion becomes an upward flow due to the air lift action of the air aerated from the air diffuser, passes through the flow path between the membrane modules, and circulates in the filtered raw water tank portion. During this time, the water in the filtered raw water tank is removed of organic matter, nitrogen and phosphorus by the microorganisms living in the filtered raw water tank.

On the other hand, the water in the filtration raw water tank portion is suction-filtered through the membrane module, and the permeated water that has permeated the membrane module is circulated to the water tank portion through the suction pipe and the suction pump.
Therefore, since pure water always circulates in the water tank, there is no need to exchange water, and since water is circulated, the water saving effect is great. Furthermore, if an ultrafiltration membrane or a microfiltration membrane is used as the filtration membrane of the membrane module, it is possible to circulate pure water that is nearly aseptic to the water tank.

Further, the solid matter attached to the membrane surface of the membrane module is swept by the upward flow and circulates in the raw filtration water tank. Therefore, since the membrane module is always washed by the upward flow, it is possible to suppress the decrease in the amount of permeate,
Maintenance is unnecessary for a long period of time.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, a water tank 11 forming a closed water system is a water tank for appreciation of fish or a water tank for aquaculture, and its wall surface is formed of a transparent body such as glass. The overflow weir 1 that divides the internal space of the water tank 11 into a water tank portion 12 and a filtered raw water tank portion 13
4 is provided, and a baffle plate 15 is arranged in the water tank portion 12 in front of the overflow weir 14. The upper end of the baffle plate 15 projects above the water surface, and the lower end of the baffle plate 15 is separated from the bottom surface of the water tank 12 by an appropriate distance.

A solid-liquid separator 16 is provided in the raw filtration water tank 13.
And the solid-liquid separation device 16 is installed in the casing 1.
6a, a plurality of membrane modules 17 arranged inside the casing 16a, and an air diffuser 18 arranged below the membrane module 17. The membrane module 17 is formed by expanding an organic membrane such as an ultrafiltration membrane or a microfiltration membrane into a flat plate shape, but a tubular shape made of a ceramic material or the like may be used. Each membrane module 17 is parallel,
In addition, a vertical flow path 19 is provided between the membrane modules 17.
Are arranged so that each membrane module 1
A suction pump 21 is provided in the middle of a suction pipe 20 that connects the permeate passage 7 and the water tank portion 12. An air supply device 22 communicates with the air diffuser 18 via an air supply pipe 23. Further, the water tank section 12 is provided with an aeration device 24.

The operation of the above structure will be described below. In the water tank portion 12, oxygen is dissolved in the water by the air aerated from the aeration device 24, and the water in the water tank portion 12 is circulated in the water tank portion 12 due to the upward flow generated by the air lift action of the aerated air. It flows over the overflow weir 14 and flows into the filtered raw water tank section 12.

In the filtered raw water tank portion 12, an air feeding device 2
Air is supplied from 2 to the air diffuser 18 through the air supply pipe 23, and air is aerated from the air diffuser 18 to the water in the filtered raw water tank portion 12. An upward flow occurs in the casing 16a due to the air lift action of the aerated air, and water flows from below the casing 16a to above through the flow passage 19 between the membrane modules 17. As a result, a downward flow occurs on the outside of the casing 16a, and water circulates in the filtered raw water tank portion 13 due to the upward flow and the downward flow, during which water is filtered.
Organic substances, nitrogen and phosphorus are removed by the microorganisms living in 3.

On the other hand, the suction pump 21 suction-filters the water in the filtered raw water tank 13 through the suction pipe 20 and the membrane module 17, and the permeated water that has permeated the membrane module 17 passes through the suction pipe 20 and the suction pump 21 and the water tank 12 Circulate.

Therefore, since the filtered pure water is always circulated in the water tank portion 12, it is not necessary to exchange the water, and since the water is circulated, the water saving effect is great. However, make-up water due to evaporation etc. is required, and in case of salt accumulation, some water must be replaced. And the membrane module 17
Since the ultrafiltration membrane or the microfiltration membrane is used as the filtration membrane of (1), it is possible to circulate pure water close to aseptic to the water tank section 12.

The solid matter attached to the membrane surface of the membrane module 17 is swept by the upward flow and circulates in the raw filtration water tank 13. Therefore, since the membrane module 17 is constantly washed by the upward flow, it is possible to suppress a decrease in the amount of the permeated liquid, and maintenance is unnecessary for a long period of time.

In addition, a drain valve 25 is provided at the bottom of the filtered raw water tank.
By providing the, it is possible to regularly pull out the waste in the raw water tank.

[0017]

As described above, according to the present invention, nitrogen and phosphorus contained in water are removed by microorganisms in the filtered raw water tank portion, and the water in the filtered raw water tank portion is filtered by the membrane module to obtain the water tank portion. Since the water is circulated in the water tank, pure water always circulates in the water tank, and there is no need to exchange water, resulting in a great water saving effect. Further, since the membrane module is constantly washed by the upward flow, it is possible to suppress a decrease in the amount of permeated liquid and maintenance is unnecessary for a long period of time.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a closed water purification apparatus according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional purification device.

[Explanation of symbols]

 11 Water Tank 12 Water Tank Section 13 Filtration Raw Water Tank Section 14 Overflow Weir 16 Solid-Liquid Separator 17 Membrane Module 18 Diffuser

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Oshima 1-247 Shikitsuhigashi, Naniwa-ku, Osaka-shi, Osaka Kubota Corporation

Claims (1)

[Claims] 1. An overflow weir for partitioning an internal space into a water tank part and a filtration raw water tank part is provided in a water tank forming a closed water system, and a plurality of membrane modules are arranged in parallel in the filtration raw water tank part and between the membrane modules. It is soaked and arranged so as to form a vertical flow path, an air diffuser is placed below the membrane module, and a suction pump is provided in the middle of the suction pipe that connects the permeate passage and the water tank in the membrane module. A purifying device for a closed water system characterized by the above.