JPH07323295A - Water purifier - Google Patents

Abstract

PURPOSE:To reduce the space for the purifier and shorten the treating time by setting the biological treating device, membrane filter and concentrator in a single treating tank and continuously conducting discrete operations in one stage. CONSTITUTION:A biological treating device 2 for bringing raw water into contact with a contact material on which microorganisms are immobilized to purify the raw water, a membrane filter 3 for permeating the biologically treated water through a filter membrane, separating solid and liq. and discharging the treated water outside the system and a concentrator 4 placed below the biological treating device 2 and membrane filter 3 and separating the solid and precipitate contained in the raw water are set in a single treating tank 1. The raw water ascends in the tank 1 by the air 5a injected from an air injection pipe 5, flows toward the membrane filter 3 in direction of the arrow C and returns toward the biological treating device 2. A so-called circulating current is generated in this case. The treated water as a filtrate is discharged outside the system, the solid and precipitate in the raw water are separated by the concentrator 4, and the concentrated precipitate is periodically discharged outside the system from the lower part of the tank 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purification apparatus for concentrating separated turbidity by subjecting raw water to biological treatment and then performing solid-liquid separation by membrane filtration, and in particular, reduction of space and increase of treatment capacity. The present invention relates to a water purification device.

[0002]

2. Description of the Related Art In a water treatment facility, particularly in a water supply facility, a water purification treatment in which solid-liquid separation is carried out by membrane filtration after removing ammoniacal nitrogen, musty odor, algae, manganese, etc. contained in raw water by biological treatment, Conventionally, it is performed through the processing steps shown in FIG. The raw water taken into the sand basin 51
After the large suspended matter and suspended matter are removed, they are stored in the landing well 52. The stored raw water is sent to the biological treatment facility 53 for biological treatment as a pretreatment for ordinary water purification treatment such as coagulation, precipitation, and filtration. And the coagulating sedimentation basin 54
After the flocs are removed by sedimentation in (1), the treated water is filtered in the filter basin 55 and the treated water is sent to the next step 56. The flocs precipitated in the coagulation sedimentation tank 54 are concentrated by the concentrating device 57 and then discharged.

[0003]

The above-mentioned conventional water purification equipment has the following problems. The raw water is subjected to biological treatment in the biological treatment facility 53, and flocs are removed by sedimentation in the coagulation sedimentation basin 54, and the next step is the filtration basin 5
It is designed to be filtered at 5. Therefore, the biological treatment facility 53, the coagulation sedimentation basin 54, and the filtration basin 55 are separately installed, and in particular, these occupy a large installation space in each water purification facility,
The ratio of the area occupied by both parties will be quite large. Thus, the processing capacity is determined by the installation area of the equipment, and the processing capacity cannot be increased in a small space. Moreover, since the filtration process is performed after the biological treatment and the precipitation process, it takes a long time.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, to provide a water purifying apparatus which can reduce the space and can shorten the processing time.

[0005]

In order to achieve the above-mentioned object, the present invention provides a biological treatment apparatus for purifying by contacting raw water with a contact material having microorganisms attached thereto, and a raw water treated with this biological treatment. A water purifying device was constructed by arranging a membrane filtration device that permeates through a filtration membrane to perform solid-liquid separation and takes out treated water to the outside of the system in a single treatment tank. Further, the present invention is a biological treatment apparatus for purifying by contacting raw water with a contact material to which microorganisms are adhered, and this biologically treated raw water is permeated through a filtration membrane for solid-liquid separation and treated water outside the system. The membrane filtration device that is taken out to the above and the concentrating device that is located below the biological treatment device and the membrane filtration device and that separates solids and precipitates contained in raw water are provided in a single treatment tank. A water purification device characterized by the above was constructed.

[0006]

In the treatment tank, the raw water is purified while circulating between the biological treatment device and the membrane filtration device, and the treated water is taken out of the system. Further, the solid matter and the precipitate contained in the raw water are separated by the concentrating device in the same treatment tank and discharged out of the system.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of a water purification device embodying the present invention. In the figure, reference numeral 1 is a treatment tank for accommodating a biological treatment device, a membrane filtration device, and a concentrating device, and is preferably formed in a hopper shape with a narrowed lower part. Inside the treatment tank 1, a biological treatment device 2 and a membrane filtration device 3 are arranged side by side with a partition plate 7 on the upper side thereof, and raw water 10 to be treated is introduced into the treatment tank 1.

The biological treatment method includes a Hanikomeu method (an immersion filter bed method) using an assembly of small plastic tubes fixed in water, a rotating disk method using a rotating disk, and a biological contact filtration method using a granular filter material. Although any known method may be used, in the present embodiment, the biological treatment device 2 is used.
As the above, the immersion filter bed method shown in FIG. 2 was adopted, and a specific example thereof will be described. An aggregate of small cylinders 21 a formed by molding a vinyl chloride sheet into a honeycomb shape (uniform hexagonal shape) as a filler 21 is immersed in the processing tank 1. A biofilm adheres to the surface of the packing material 21, and raw water is passed through the packing material 21 from the bottom to the top in the figure to bring it into contact with the biofilm, whereby ammonia nitrogen in the raw water, algae, Musty odor, anionic surfactant, manganese, etc. can be effectively removed.

An air jet pipe 5 is provided on the lower side of the biological treatment apparatus 2, and air 5a is continuously or intermittently fed from an air supply source provided outside the treatment tank 1. The presence of dissolved oxygen is essential for the oxidation / decomposition reaction of organic substances by microorganisms and the oxidation of ammonia nitrogen. Therefore, when there is a risk of lack of oxygen in the raw water, it is necessary to blow air to supplement oxygen.

Further, the raw water rises in the treatment tank 1 by the air 5a ejected from the air ejection pipe 5, flows toward the membrane filtration device 3 side as shown by an arrow C in FIG. A so-called circulating flow is generated that returns to the side. Therefore, the contact frequency of the biofilm and water can be increased, and the treatment effect can be enhanced. Further, since the circulation flow is caused by the air 5a ejected from the air ejection pipe 5, it is not necessary to separately provide a circulation pump, and the energy can be effectively used. The thickened biofilm is shed by the shearing force generated by the circulation flow, and at the same time, new microorganisms are increased, and the biofilm having high activity is always retained.

Next, the membrane filtration device 3 will be described. In the present embodiment, as the membrane filtration device 3, the external pressure type cross flow filtration device shown in FIG. 3 was adopted. The hollow fiber membrane module 31 arranged in the treatment tank 1 is a porous membrane hollow fiber obtained by, for example, dissolving cellulose acetate in a good solvent and spinning a polymer solution obtained by adding a metal salt and an additional solvent to the good solvent. 31a and a hollow portion 31b. The raw water 10 is flown outside the membrane layer 31a from the upper side to the lower side in the drawing in parallel with the membrane layer 31a, and permeates the membrane layer 31a in a direction (arrow direction) orthogonal to the membrane layer 31a. By this cross-flow filtration, the treated water 20, which is a filtrate that has been solid-liquid separated and has been permeated to the inside of the membrane layer 31a, that is, the hollow portion 31b, is taken out of the system. On the outside of the membrane layer 31a of the hollow fiber membrane module 31, the suspended matter 8 that has been solid-liquid separated is attached.

An air jetting pipe 6 is provided on the lower side of the membrane filtration device 3 and the air 6a is intermittently fed from an air supply source provided outside the processing tank 1 to thereby form the membrane layer 31a.
The suspended matter 8 adhering to the outside of the is removed. The precipitate accumulated in the lower part of the processing tank 1 is regularly discharged out of the system.

As described above, since the biological treatment device 2 and the membrane filtration device 3 are housed in the single treatment tank 1, the biological treatment device and the membrane filtration device are smaller than those separately installed. The space can be increased, and at the same time, the processing time can be shortened.

Next, an example in which the concentrating device 4 is arranged below the biological treatment device 2 and the membrane filtration device 3 will be described with reference to FIG. As shown in a specific example of FIG. 4A, the concentrating device 4 includes a slant plate settling device in which a required number of slant plates 41 having a slant angle of 60 degrees with respect to the vertical direction are juxtaposed at predetermined intervals. As shown in FIG. 4 (b), a slant pipe settling device is used in which a required number of hexagonal (or circular) pipes 42 are arranged in close contact with each other at an inclination angle of 60 degrees with respect to the vertical direction. To separate solids and precipitates contained in the raw water. The concentrated precipitate is regularly discharged from the lower part of the processing tank 1 to the outside of the system.

As described above, in the water purification apparatus in which the biological treatment device 2, the membrane filtration device 3 and the concentrating device 4 are housed in the single treatment tank 1, the biological treatment device, the membrane filtration device and the concentrating device are separately provided. The space can be reduced as compared with the installed one, and at the same time, the processing time can be shortened.

[0016]

As described above, according to the water purification apparatus of the present invention, the biological treatment apparatus, the membrane filtration apparatus, and the concentrating apparatus are housed in a single treatment tank, and the raw water is circulated in the treatment tank. Flowing, performing biological treatment and membrane filtration, each process of concentrating with a concentrating device can be continuously processed in one step, so compared to a conventional device that performs each processing step individually, The installation space can be reduced, and the processing time can be significantly shortened.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a water purifier according to the present invention.

FIG. 2 is a perspective view showing an example of a biological treatment apparatus used in the water purification apparatus of the present invention.

FIG. 3 is a perspective view showing an example of a membrane filtration device used in the water purification device of the present invention.

FIG. 4 is a perspective view showing an example of a concentrating device used in the water purifying device of the present invention.

FIG. 5 is a flow chart showing a treatment process of a conventional water purifier.

[Explanation of symbols]

 1 ... Treatment tank 2 ... Biological treatment device 3 ... Membrane filtration device 4 ... Concentration device 5 ... Air jet pipe 6 ... Air jet pipe 10 ... Raw water

Claims (6)

[Claims] 1. A biological treatment apparatus for purifying by contacting raw water with a contact material to which microorganisms are adhered, and a biological treatment raw water which is permeated through a filtration membrane to perform solid-liquid separation to bring the treated water out of the system. A water purifier characterized in that a membrane filtration device to be taken out is arranged in a single treatment tank. 2. A biological treatment apparatus for purifying by contacting raw water with a contact material on which microorganisms are adhered, and a biological treatment raw water which is permeated through a filtration membrane to perform solid-liquid separation to bring the treated water out of the system. A membrane filtration device for taking out and a concentrating device located below the biological treatment device and the membrane filtration device for separating solids and precipitates contained in raw water were arranged in a single treatment tank. A water purification device characterized by that. 3. The biological treatment apparatus is an immersion filter apparatus for immersing a filler to which organisms are likely to adhere in a water tank, forming a biological film on the surface of the filler, and contacting with raw water to purify it. The water purifier according to claim 1 or 2. 4. The membrane filtration device is an external pressure type cross-flow filtration device which causes treated water to flow to the outside of the hollow fiber membrane in parallel with the membrane and permeate to the inside of the membrane for solid-liquid separation. The water purifier according to claim 2. 5. The water purifier according to claim 1 or 2, wherein air is blown into the biological treatment apparatus to provide an air jet pipe for supplying oxygen to the raw water. 6. The water purifier according to claim 2, wherein the concentrating device is an inclined plate provided in a required number at predetermined intervals or an inclined pipe provided in a required number in close contact with each other.