JPS59139910A - Magnetic separation method - Google Patents

Abstract

PURPOSE:To efficiently and sufficiently separate and remove a non-magnetic suspended substance, in performing magnetic separation by adding a magnetic material and a flocculant in a liquid containing a non-magnetic suspended substance, by adding a magnetic material uniformly dispersed by ultrasonic waves. CONSTITUTION:Raw water containing a non-magnetic suspended substance is sent to an arranged pipe by a pump 14 while a dispersion 71 having magnetite powder particles uniformly dispersed therein by an ultrasonic oscillator 61 and a dilute solution 42 of a flocculant subjected to stirring treatment by a blade type stirrer 23 are added on the way of the arranged pipe by pumps 15, 16. In the next step, this liquid mixture is treated with an electromagnetic filter 52 to obtain treating water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic separation treatment method, more specifically, a method for coagulating non-magnetic suspended matter in a liquid into a magnetic floc in the presence of a magnetic substance, a coagulant, etc. The present invention relates to a magnetic separation treatment method in which non-magnetic suspended matter can be efficiently and sufficiently separated and removed from a liquid by using a magnetic substance uniformly dispersed by ultrasonic waves in the magnetic separation process.

Organic or inorganic non-magnetic suspended substances (hereinafter simply abbreviated as SS) are mixed in urban sewage, industrial wastewater, waste liquids from various manufacturing processes, and activated sludge treated water. ○If these are released into the IT environment, they become a source of pollution, so they need to be disposed of by some means.

In recent years, magnetic separation processing has been used to treat liquids containing such SS (hereinafter simply referred to as raw water). In this case, the magnetic separation treatment involves co-agglomerating the SS in the raw water in the presence of an appropriate magnetic substance, coagulant, etc. to form magnetic flocs that can be subjected to magnetic separation treatment, and then magnetically separating the SS. Typically, for example, an electromagnetic filter is used as the magnetic separation device, and powder particles of magnetite, which is a ferromagnetic material, are used as the magnetic material.

However, conventional magnetic separation treatment in such cases generally involves adding a stirred mixture of magnetic powder particles obtained by mechanically stirring with a blade stirrer to raw water, adding a flocculant,
This method involves co-agglomerating the SS in the raw water with magnetic powder particles to form magnetic flocs, which are then sent to a magnetic separator, but in practice, according to this conventional method, there is still a non-negligible amount of particles in the treated water. SS is floating,
Particularly in today's world, where removal of SS is extremely demanding both qualitatively and quantitatively, it is still not sufficient, and there is a high demand for more efficient and sufficient separation and removal of SS by magnetic separation treatment. .

In view of the above, the present invention provides a magnetic separation treatment method that can efficiently and sufficiently separate and remove SS in raw water.

Hereinafter, the structure of the present invention will be explained in detail by using an electromagnetic filter as a magnetic separation device and macnetite powder as an example of the groove/magnetic material, while comparing with a conventional method based on the drawings.

FIG. 1 is a schematic system diagram illustrating the processing procedure of the conventional method. In the middle of the piping through which raw water is sent by the pump 11, a mixed liquid 31 of magnetite particles stirred by the blade-type stirrer 21 and a diluted solution 41 of the coagulant are pumped to the blade-type stirrer 22, respectively. The treated water is then supplied to an electromagnetic filter 51 to obtain treated water. The electromagnetic filter 51 captures and accumulates magnetic flocs of SS and magnetite powder coagulated by the coagulant, and these are discharged to the system 1 by conventional backwashing after continuous treatment for, for example, several hours.

In addition to the examples shown in the drawings, such conventional methods include
In some cases, a mixing tank for raw water and macnetite powder particles, a co-flocculation tank using a flocculant, etc. are installed, or magnetite powder particles and a flocculant are added to raw water at the same time, but either method actually requires magnetic separation treatment. As a result, a non-negligible amount of SS still floats in the treated water.

When the present inventors investigated the cause of this problem, they found that in the conventional method, the magnetite powder particles added to the raw water were not uniformly dispersed, and that some of the magnetite powder particles were agglomerated between each other. Since the SS is not in a state where it can adsorb SS in the raw water, the SS is either supplied to the electromagnetic filter in the form of flocs by the flocculant without forming magnetic flocs, or it forms magnetic flocs. Even if the SS and magnetite powder particles are not close together, the magnetic flocs may be supplied to the electromagnetic filter, and the SS of such flocs may not be captured by the electromagnetic filter and may be entrained in the treated water and shuffled. It turns out.

Therefore, the inventors of the present invention have made further efforts to solve this problem.As a result of their research, they found that if the magnetite powder to be added to raw water is dispersed in the liquid using ultrasonic waves, the magnetite particles Magnetite powder particles are in a uniformly dispersed state in which each particle is broken up into pieces, and at the same time, the dust, etc. that often adhere to the surface of the powder particles are removed, and the particles are in an activated state. The difference between adding the water to the raw water is
It was discovered that SS in raw water is efficiently, tightly and strongly adsorbed to each magnetite powder particle, and that these particles form magnetic flocs using a flocculant, and these magnetic flocs are reliably captured by an electromagnetic filter. , we have completed the present invention.

2 and 3 show different embodiments of the present invention (political system diagrams. In the case of FIG. 2, an ultrasonic oscillator 61 Uniform dispersion of Maguitite powder 71 and blade stirrer 23
Dilute solution of flocculant by pump 42 or pump 1.5.1 respectively
6 and then subjected to an electromagnetic filter 52 to obtain treated water. In the case shown in Figure 3, the raw water is pumped 1
7, the stirred mixture 32 of magnetite powder particles is stirred by an ultrasonic oscillator 6 by a blade-type stirrer 24 in the middle of the pipe to which the liquid is sent.
A uniform dispersion liquid 7 as described above is prepared in a dispersion container 8J provided with
2 and a diluted solution 43 of the flocculant produced by the O/impeller stirrer 25 are added by pumps 18 and 19, respectively, and then passed through the electromagnetic filter 53 to obtain treated water.

In all of the illustrated embodiments, the magnetite particles are broken up one by one as described above, and are applied to raw water as a homogeneous dispersion liquid 71,72 in an active state, and captured by an electromagnetic filter 52,53. The magnetic flocs are discharged from the system by backwashing as in the conventional method.

In the present invention, the magnetite powder particles are representative examples of a magnetic material, and the electromagnetic filter is representative examples of a magnetic separation device, and other well-known magnetic materials and magnetic separation devices may be used. The flocculant is one or more types selected as appropriate depending on the properties of the target raw water, and usually anionic or nonionic polymer flocculants, such as polyaluminum chloride, may be used. .

In order to make the effects of the present invention explained above more concrete, the following Table 1 is illustrated. In the table, the conventional example is shown in Figure 1, Example 1 is shown in Figure 2, and Ushida Example 2 is shown in Figure 3. The capacity of the tank equipped with the ultrasonic oscillator 61 was the same as that of the conventional example.
:Dispersion container 8 equipped with an ultrasonic oscillator 62 in FIG.
1 capacity: 0 Note that the SS concentration of the treated water is the average value of multiple 71111 constant values during repeated continuous treatments. ) As is clear from the results in Table 1, in each example, the SS concentration in the treated water was significantly lower than in the conventional example, and the efficiency was improved by the magnetite powder particles used and the ultrasonic waves. It can be seen that the system is functioning effectively and adequately.

According to the present invention, SS in raw water can be separated and removed more efficiently and sufficiently in the magnetic separation process, and there is no phenomenon in which magnetite particles are deposited in tanks or in the middle of piping, which occurs in conventional methods. .

[Brief explanation of the drawing]

Figure 1 is a schematic system diagram illustrating the processing procedure of the conventional method;
3 and 3 are schematic system diagrams showing different embodiments of the present invention. 11-19 Pump, 21-25・Blade type stirrer, 31.32 Stirring mixed liquid, 41-43・Diluted solution, 51-53 Electromagnetic filter, 61.62 Ultrasonic oscillator, 71.72 Uniform dispersion liquid, 81 Dispersion Container, Patent Applicant Daido Steel Co., Ltd. Agent Patent Attorney Hiroshi Iriyama Figure 1 Figure 3

Claims (1)

[Claims] 1. Add a magnetic substance, a flocculant, etc. to a liquid containing non-magnetic suspended matter as appropriate to make the non-magnetic suspended matter into a magnetic floc, and then perform magnetic separation treatment or uniformly disperse it using ultrasonic waves. 7. Magnetic separation method characterized by adding a magnetic substance.