JPH0768271A - Water purifying method - Google Patents

Abstract

PURPOSE:To provide a water purifying method excellent in working efficiency and not inhibiting a natural ecosystem at all by circulating water containing a large amt. of fine air bubbles to polluted water for adding a polymeric flocculant to the polluted water and floating a muddiness and contamination causing substance as floatable flocs to collect and remove the same. CONSTITUTION:The water of a basin 1 is supplied to a Venturi tube 5 from an intake 2 while air is supplied to the Venturi tube 5 by a compressor 4 to generate fine air bubbles, which are, in turn, uniformly dispersed in the taken-in water by an air bubble mixer 6. The air bubble dispersed water is sent to a gas-liquid separator 7 to remove large air bubbles and emitted to the basin 1 through water jet orifices 9 while a polymeric flocculant is added to and compounded with the water from a hopper 8. Whereupon, the functional group of the polymeric flocculant adsorbs and flocculates a muddiness and contamination causing substance and porous flocs are formed while they include fine air bubbles to float on the surface of the water within a short time. This floating scum 11 is taken out of basin 1 using an Oliver type collector.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a water purification method.

[0002]

2. Description of the Related Art Conventionally, as a method for purifying contaminated water in a closed system, for example, an inorganic coagulant and a synthetic polymer coagulant are added to the contaminated water to settle a pollutant and a pollutant in a sedimentation tank. There is known a method of precipitating and removing this. However, in such a method, it is necessary to separately provide a settling tank, a large space must be secured for that purpose, and moreover, several days are required for the precipitation of pollutants and pollutants, and the work efficiency is high. It has the drawback of being extremely bad. Furthermore, according to the method, by the coagulant,
Even useful microorganisms will be forced to settle, which may result in the destruction of natural ecosystems.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a new water purification method which solves the above problems.

That is, the present invention relates to polluted water in a closed system,
While circulating water containing a large amount of fine bubbles under high pressure and high speed, by adding a polymer flocculant, the contaminants and pollutants contained in the water are suspended as low-specific-gravity floating flocs, Then, it relates to a method for purifying water, which is characterized by collecting and removing this.

The water to be treated in the present invention is not particularly limited as long as it is a contaminated water of a closed system in which water does not flow, and for example, water of a golf course pond,
Examples include water from reservoirs, pool water, and small-scale industrial wastewater.

As a device used for circulating water containing a large amount of fine bubbles under high pressure and high speed, conventionally known fine bubble generators can be widely used. The degree of high pressure and high speed is not particularly limited and may be appropriately determined depending on the size of the closed water system to be applied, the degree of water pollution, and the like.

In the present invention, it is essential to add and blend a polymer flocculant into closed polluted water while circulating water containing a large amount of fine bubbles under high pressure and high speed. As the polymer flocculant used, conventionally known ones can be widely used as long as they are water-soluble. For example, natural polymer compounds such as chitin chitosan, polyacrylic acid soda, polyacrylic acid amide, polyacrylic acid imide and the like are synthesized. Polymer compounds and the like can be mentioned. These polymer flocculants may be used alone or in combination of two or more. In the present invention, it is particularly desirable to use chitin chitosan in combination with polyacrylic acid soda or polyacrylic acid amide, and thus the intended effect of the present invention can be remarkably exhibited. The amount of the polymer flocculant added is not particularly limited and may be appropriately determined depending on the size of the closed water system to be applied, the degree of water contamination, and the like.

[0008] By the above treatment, the pollutants and pollutants contained in water become agglomerates of low specific gravity and float on the water, and these are collected by conventionally known collecting means, for example, screw type collecting. It may be removed by a method using a machine, a method using an oliver type (drum rotation type) collector, a method using a belt conveyor type collector, or the like.

One embodiment of the method of the present invention will be described below with reference to FIG.

A part of the closed water in the pond (1) is pumped from the water intake (2) to the venturi (5). On the other hand, air is sent to the venturi (5) by the compressor (4), where fine air bubbles (3 μm)
The following) is generated in water, and fine gas bubbles are made to be uniformly dispersed in water in the subsequent gas-liquid mixing device (6). As the gas-liquid mixing device, conventionally known ones can be widely used, and examples thereof include a static mixer, a scare mixer, and a honeycomb mixer. These gas-liquid mixing devices may be appropriately selected and used according to the degree of pollution of water quality, viscosity, and the like, and the object of the present invention can be achieved to some extent even when such a gas-liquid mixing device is not used. The water containing a large amount of fine air bubbles obtained above is then sent to the gas-liquid separation tank (7), where large-sized air bubbles are removed, and then the water passes through the polymer coagulant injection hopper (8). Then, it is discharged to the pond (1) through the water injection port (9). In the polymer coagulant injection hopper (8), the polymer coagulant is added to and mixed with water containing fine bubbles. The polymer flocculant is dissolved in water in a dissociated state, but after being discharged into the pond (1) through the water injection port (9), the functional group (ionic group) possessed by each polymer substance is changed. Cross-linking reaction with inorganic or organic colloidal suspension substances or electrolytes that are pollutants and pollutants, adsorbs, coagulates, and agglomerates to form a clathrate containing inclusions of pollutants and pollutants. . At this time, a large amount of fine bubbles are simultaneously included to form a porous aggregate (scum). Since this aggregate has a low specific gravity and floatability, it floats on water in a short time. On the other hand, water containing a large amount of fine bubbles and added with the polymer coagulant is discharged from the water injection port (9) with considerable force, so that the water to be treated is agitated by water pressure, It plays a role of promoting the aggregating action and the like of the above-mentioned polymer aggregating agent in a wide range. The water injection port (9) may have the same structure as the relief valve. In the present invention, the scum floating next on the water may be taken out from the pond (1) using an oliver type collector.

[0011]

EFFECTS OF THE INVENTION According to the present invention, since pollutants and pollutants cause scum to float on the water, it suffices to remove them, and it is not necessary to separately provide a sedimentation tank as in the conventional case. It has become possible to purify water on a small site. Moreover, according to the present invention, the time required for the scum to float on the water is a very short time of about several hours, which is excellent in work efficiency. In addition, by carrying out the method of the present invention, the natural ecosystem is not disturbed at all.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the method of the present invention.

[Explanation of symbols]

(1) ... Pond, (2) ... water intake, (3) ... pump,
(4) ... Air compressor, (5) ... Venturi, (6) ... Gas-liquid mixing device, (7) ... Gas-liquid separation tank,
(8) Polymer coagulant injection hopper, (9) ... Water jet port,
(10) ... Air bubbles, (11) ... Scum, (12) ... Oliva type collector

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ichizo Yagi 6-chome Nakamikunigaoka-cho, Sakai-shi, Osaka 2-19 (72) Inventor Miyoko Fujita 4-6-14 Shin-kanaoka-cho, Sakai-shi, Osaka

Claims (1)

[Claims] 1. A closed system of polluted water, in which water containing a large amount of fine bubbles is circulated under high pressure and high speed, and a polymer flocculant is added to the polluted water and the cause of contamination. A method for purifying water, which comprises suspending a substance as a floating aggregate having a low specific gravity, and then collecting and removing this.