JPH0975629A - Water purifying magnetic separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an efficient water purifying magnetic separator separating a substance to be separated from washing water to concentrate the same without providing a magnetic field generating means separately from a water purifying magnetic separation part. SOLUTION: Raw water in a reservoir 1 is once stored in a raw water tank 5 through a filter 3 and a magnetic powder is added herein to guide the raw water to a water purifying magnetic separation container 15a as magnetic floc. A magnetic separation part is equipped with the container 15a being a first magnetic container, an air-core coil 16, a high grade magnetic filter 20a being a first magnetic filter, a perforated magnetic pole 18a and a yoke 19. A small concn. magnetic separation container 15b is provided as a second magnetic container and a filter 20b and a perforated pole 18b are built in the container 15b in the same way. Pretreated water 12 is filtered by the filter 20a in the first magnetic container 15a to attract magnetic floc to purify raw water and, after the filter 20a is backwashed, backwashing waste water containing the magnetic floc is filtered by the second filter 20b to attract the magnetic floc and the treated water is allowed to flow to the second filter 20b and concn. waste water high in the concn. of magnetic floc is obtained from backwashing waste water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic separation apparatus for water purification, and is particularly suitable for separating pollutants in raw water as magnetic flocs and further concentrating waste water generated when the magnetic flocs are backwashed. The structure of a magnetic separation device for water purification.

[0002]

2. Description of the Related Art An electromagnet using a DC power source is used as a magnetic field generator for externally applying a high gradient electromagnetic filter for water purification. This structure is described in Chemical Engineering, Vol. 45, No. 4 (1
(981) pp. 235 to 239.
The high-gradient electromagnetic filter is surrounded by a yoke made of iron, and this yoke is used as a passage for magnetic force lines to prevent leakage of magnetic force lines.
The coil of the magnetic field generating means is arranged inside the yoke, and the filter container accommodating the high-gradient electromagnetic filter is arranged in the central portion. In this filter container, the magnetic poles with a large number of holes form the high-gradient electromagnetic filter. It is sandwiched and placed upside down.
Here, the high-gradient magnetic filter is composed of magnetic fine wires, and is filled with, for example, a wire mesh-shaped magnetic stainless fine wire or metal wool. The separated substances (magnetic flocs) accumulated in this filter are washed with water after removing the magnetic field. Regarding the method of further separating and concentrating the separated matter from the wastewater generated by this washing with water, a dehydration step of adsorbing the separated matter on a permanent magnet different from the purification magnetic separation section is disclosed in JP-A-60-244390. .

[0003]

However, in the prior art, in order to separate and concentrate the magnetic floc separated matter from the waste water, it is necessary to provide a magnetic field generating means such as a permanent magnet separate from the purification magnetic separation section. was there.

An object of the present invention is to provide a magnetic separation apparatus for water purification which separates and concentrates a magnetic floc separated matter from waste water without providing a magnetic field generating means separate from the purification magnetic separation section.

[0005]

In order to achieve the above object, the first magnetic separation apparatus for water purification of the present invention comprises adding magnetic powder and an aggregating agent to raw water containing pollutants. A device for purifying raw water containing magnetic flocs, which is formed by aggregating a pollutant and magnetic powder by means of a first magnetic container for introducing raw water containing magnetic flocs from below,
Electromagnetic coil provided along the outer peripheral side surface of the magnetic container, a first magnetic filter loaded in the first magnetic container for adsorbing magnetic flocs contained in the raw water, and raw water discharged from the upper part of the first magnetic container. A treated water storage tank for storing the treated water as treated water,
A backwash drainage tank for storing backwash drainage discharged when backwashing the magnetic flocs adsorbed on the first magnetic filter by using the treated water from the treated water tank, a first magnetic container and a first magnet A second magnetic container having a filter penetrating in the vertical direction, and a second magnetic filter for adsorbing magnetic flocs contained in the backwash drainage that is loaded in the second magnetic container and is fed from the backwash drainage storage tank. And the backwash wastewater and the treated water supplied to the second magnetic filter are introduced from the upper part of the second magnetic container, and the magnetic flocs adsorbed on the second magnetic filter are treated water from the treated water storage tank. The feature is that magnetic flocs can obtain concentrated wastewater with a high concentration than the backwash wastewater.

[0006] The first magnetic separation apparatus for purifying water, when raw water containing magnetic flocs is introduced into the first magnetic container,
At the same time, it is preferable to introduce backwash drainage into the second magnetic container and operate so as to obtain treated water and concentrated drainage.

In order to achieve the above object, a second water purification magnetic separation device of the present invention is a device for purifying raw water containing magnetic flocs, like the first water purification magnetic separation device. Yes, and has a first magnetic container, an electromagnetic coil, a magnetic filter loaded in the first magnetic container, a treated water storage tank, and a backwash drainage storage tank among the components of the first water purification magnetic separation device. In addition, a second magnetic container, which is arranged between the first magnetic container and the electromagnetic coil, is provided with a rotary screw for scraping the magnetic flocs from the backwash drainage from the backwash drainage storage tank, and the second magnetic container. A magnetic separation device for water purification, comprising: a magnetic field gradient generating cylinder that covers the outer peripheral surface of the container and is formed by alternately stacking annular ferromagnetic bodies and nonmagnetic bodies.

The second magnetic separation device for water purification is arranged such that when raw water containing magnetic flocs is introduced into the first magnetic container,
At the same time, it is preferable to introduce backwash drainage into the second magnetic container to generate treated water and scrape out magnetic flocs. In the second magnetic separation device for water purification, the backwash drainage is supplied from the upper part of the second magnetic container, and the rotary screw is configured to scrape up the magnetic flocs adhering to the inner wall surface of the second magnetic container. Preferably.

[0009]

The processing steps by the first magnetic separation apparatus for water purification of the present invention are as follows.

(1) Raw water containing magnetic flocs is filtered by a first magnetic filter loaded in a first magnetic container, and the magnetic flocs are adsorbed by the first magnetic filter,
A step of purifying, (2) a step of backwashing to remove the magnetic flocs from the first magnetic filter, (3) a backwash drainage containing the magnetic flocs is filtered by a second magnetic filter, and the second The process comprises adsorbing magnetic flocs on the magnetic filter, and (4) flowing treated water for removing magnetic flocs from the second magnetic filter to obtain concentrated wastewater having a higher magnetic floc concentration than the backwash wastewater. The steps (1) and (4) may be performed in different time zones, but by performing them simultaneously, the operating time of the device can be shortened.

The treatment step by the second magnetic separation apparatus for water purification of the present invention comprises the above steps (1) and (2) and the following step (3 '). (3 ') The backwash drainage is introduced into the second magnetic container containing the rotary screw, and the magnetic flocs adhering to the inner wall surface of the second magnetic container in which a magnetic field with a high gradient is generated by the magnetic field gradient generation cylinder are rotated. The process of scratching with. The step (1) and the step (3 ′) may be performed in different time zones, but by performing them at the same time, the operating time of the device can be shortened.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. As a pretreatment for the magnetic separation step, the raw water to be treated with water is mixed with magnetic powder such as ferrosoferric oxide and a flocculant of vanadium sulfate containing aluminum or polyaluminium chloride, and stirred to form raw water. The solid suspended matter and pollutants of algae, fungi, and microorganisms are combined with magnetic powder by a flocculant to form colloidal and many magnetic flocs having magnetism. When passing through the high gradient magnetic filter, these magnetic flocs are attracted to the surface of the magnetic fine wire that constitutes the filter and separated from the raw water.

Operation of the purification system using the magnetic separation device of this embodiment is performed as follows. Raw water in the reservoir 1 is temporarily stored in a raw water storage tank 5 by a pump 4a through a filter 3 for removing large dust from the water conduit 2, and the raw water 6 is stored in the raw water 6 from the chemical regulator 7 and magnetic powder of ferric oxide and polyaluminum chloride. A flocculant such as the above is added through a conduit 8 and stirred in a stirring tank 9 by a stirrer 11 rotated by a motor 10 to produce pretreated water 12 containing magnetic flocs. The pretreated water 12 passes through the water conduit 14 through the valve 13 and flows into the purified magnetic separation container 15a.

The magnetic separation part is a purified magnetic separation container 15a as a first magnetic container into which the pretreated water 12 is introduced from below.
An air-core coil 16 as an electromagnetic coil surrounding the side surface of the container 15a, a high-gradient magnetic filter 20a as a first magnetic filter installed in the container 15a, and this filter 2
An iron yoke 19 that surrounds the porous magnetic poles 18a and the air-core coil 16 that respectively cover the upper and lower surfaces of 0a and have a large number of through holes in the vertical direction is provided. Further, a small concentrated magnetic separation container 15b is provided as a second magnetic container penetrating the purification magnetic separation container 15a, and the container 15b is another high gradient magnetic filter 20b serving as a second magnetic filter, which is above the filter 20a. Each porous magnetic pole 18b that covers the lower surface is built in.

Further, various storage tanks are provided which are connected to the magnetic separation section by piping. That is, the treated water storage tank 23 for storing the treated water discharged from the upper portion of the purified magnetic separation container 15a and the backwash drainage tank 29 for storing the drainage discharged from the purified magnetic separation container 15a when the high gradient magnetic filter 20a is backwashed.
a, a concentrated drainage storage tank 29b for storing concentrated drainage discharged from the concentrated magnetic separation container 15b when cleaning the other high-gradient magnetic filter 20b is installed.

When the pretreated water 12 is purified, a DC power supply is supplied from the DC power supply 17 to the air-core coil 16. A magnetic field proportional to the direct current is generated in the cylindrical purifying magnetic separation container 15a, the magnetic field is made uniform over the entire surface of the high gradient magnetic filter 20 by the porous magnetic poles 18a for water passage, and the iron yoke 19 forms the magnetic field lines. To prevent external leakage of magnetic field lines. The uniform magnetic field magnetizes the magnetic fine wire filler of the high gradient magnetic filter 20a, that is, the magnetic wire mesh, the metal wool, and the like. The magnetic field in the purification magnetic separation container 15a is disturbed due to the magnetized magnetic wire filling, and the magnetic flux is locally concentrated and dense, and a large number of high magnetic field gradient portions are generated. When the pretreated water 12 containing magnetic flocs is fed from below in an upward flow, the magnetic flocs in the raw water are captured on the surface of the magnetic fine wire of the packing with a large magnetic force, and the purified raw water is treated as the treated water by the valve 21a. It is temporarily stored in the treated water storage tank 23 through the water pipe 22a and returned to the reservoir 1 through the water conduit 24a.

After a certain amount of magnetic flocs are captured by the high gradient magnetic filter 20a, the high gradient magnetic filter 20a is backwashed in order to restore the performance of magnetic separation. For backwashing, first, the valve 13 is closed to stop the water supply of the pretreated water 12. Next, the DC power supply 17 is turned off, and after eliminating the magnetic field, the high gradient magnetic filter 20a is passed through the valve 21a from above.
A predetermined amount of the treated water stored in the treated water storage tank 23 is backwashed as wash water, and the valve 25a of the backwash drainage storage tank 29a is opened. Also, at this time, the air tank 26 is connected to the valve 27a and the conduit 28a.
The magnetic flocs adhering to the surface of the magnetic fine wires are washed away by supplying air through the air bubble while carrying out air bubbling, and the drained water after washing is stored in the backwash drainage storage tank 29a. Here, the washing water is 3 to 4 times the filling volume of the high gradient magnetic filter 20a.
Since the double amount is used, the concentration of the magnetic flocs adsorbed on the filter 20a is considerably diluted. After that, the valve 25a of the backwash drainage storage tank 29a and the valve 27a of the air tank 26 are closed, DC power is again supplied to the air-core coil 16 from the DC power supply device 17, and the valve 13 of the agitation tank 9 is opened.
Restart magnetic separation.

During the magnetic separation operation for purifying the pretreated water 12, the backwash drainage in the backwash drainage storage tank 29a which was backwashed before that is passed through the water conduit 22b and the valve 21b to the magnetic field of the air-core coil 16. Water is passed through the cylindrical concentrated magnetic separation container 15b arranged. The magnetic field in the concentrated magnetic adsorption container 15b is made uniform by the porous magnetic pole 18b, and the high gradient magnetic filter 20b is obtained.
Disturbance occurs in the magnetic field, and the magnetic flux is locally concentrated and dense, resulting in a large number of high magnetic field gradient portions. The magnetic flocs in the backwash drainage are adsorbed by the high gradient magnetic filter 20b by the water flow, and the treated water is returned to the reservoir 1 by the pump 4b through the water conduit 24c and the valve 25c. During this operation, the valve 21 provided in the connecting pipe between the treated water storage tank 23 and the concentrated magnetic separation container 15b
c, the valve 27b provided in the connecting pipe between the air tank and the concentrated magnetic separation container 15b, and the valve 25b of the concentrated waste water storage tank 29b are closed.

The magnetic flocs accumulated in the high gradient magnetic filter 20b filled in a space smaller than the filling space of the high gradient magnetic filter 20a are transferred from the concentrated magnetic separation container 15b to the reservoir 1 during the backwash operation of the high gradient magnetic filter 20a. The valve 25c provided in the return pipe of the above is closed, and the valve 21c provided in the pipe from the treated water storage tank 23 to the concentrated magnetic separation container 15b,
The valve 25b of the concentrated drainage storage tank 29b and 27b provided in the pipe from the air tank to the concentrated magnetic separation container 15b are opened. The washing water flows into the concentrated magnetic adsorption container 15b through the valve 21c, and at the same time, air is supplied from the air tank 26 through the valve 27b and the conduit 28b to perform air bubbling to wash and remove the magnetic flocs adhering to the surface of the magnetic fine wire. Concentrated wastewater containing magnetic flocs in high concentration by washing concentrated wastewater storage tank 29
Store in b. Here, the amount of washing water used is three times lower than the filling space of the high-gradient magnetic filter 20b, or four times as much. It is even thicker, and the volume of drainage per fixed amount of magnetic flocs becomes smaller. The concentrated waste water is separately carried out from the concentrated waste water storage tank 29b, and is discarded or incinerated in a landfill or the like, but the treatment cost is greatly reduced because the volume is reduced.

According to one embodiment of the present invention, the concentrated magnetic separation unit for concentrating the backwash waste water is installed in the magnetic field generated by the magnetic field generating means of the purification magnetic separation unit for treating raw water. The magnetic field generating means for concentrating the wash water can be omitted, and the manufacturing cost of the purifying device can be reduced.

Another embodiment according to the present invention is shown in FIG. The present embodiment is different from FIG. 1 in that the concentrated magnetic adsorption unit is installed outside the purification magnetic separation unit for treating raw water, and the concentrated magnetic adsorption unit is installed in the magnetic field generated by the magnetic field generating means of the purification magnetic separation unit. However, the concentrated magnetic adsorption part has a mechanical magnetic floc scraping structure. The operation of the purified magnetic separation and the backwash operation flow of the purified magnetic separation unit are the same as in the case of FIG.

During the magnetic separation operation for purifying the pretreated water 12 containing the magnetic powder and the coagulant added to the raw water, the backwash drainage in the backwash drainage storage tank 29a which was backwashed before that is conducted by the water pipe 22b and the valve 25.
Water is passed through b in the magnetic field of the air-core coil 16 and into the cylindrical concentrated magnetic adsorption container 30 arranged on the outer peripheral portion of the purification magnetic separation container 15a. In order to generate a high magnetic gradient in the concentrated magnetic adsorption container 30, especially in the inner wall of the concentrated magnetic adsorption container 30, for example, an annular ferromagnetic material and a non-magnetic material are alternately laminated on the outer periphery of the concentrated magnetic adsorption container 30. The magnetic field gradient generating cylinder 31 is placed. Therefore, the magnetic flocs in the backwash drainage are adsorbed on the inner wall of the concentrated magnetic adsorption container 30, and the treated water from which the magnetic flocs are removed is returned to the reservoir 1 by the pump 4b through the water pipe 24c and the valve 25c. The magnetic flocs adsorbed on the inner wall of the concentrated magnetic adsorption container 30 are rotated by a motor 32 and scraped by a scraping screw 33.
As a result, the concentrated magnetic adsorption container 30 moves upward along the inner wall of the container 30 and is recovered in the magnetic floc recovery tank 34.

According to the present embodiment, since the magnetic flocs can be continuously concentrated without backwashing, the concentration of the magnetic flocs in the wash water is further increased, and the final waste volume is further reduced. Become. Also, the concentrated magnetic adsorption container 30
Since it can be disposed outside the purification magnetic separation unit, the purification magnetic separation unit space for purifying raw water can be widened, and a larger amount of purification treatment can be secured. The magnetic flocs with a reduced volume are separately carried out from the magnetic floc recovery tank 34, and finally discarded or incinerated at a landfill site, etc., but since the volume is reduced, the processing cost is further increased. Is reduced to.

The above-mentioned raw water is water containing impurities that pollute it with rivers, dams, lakes, seawater, reservoirs, industrial wastewater, sewage, rainwater, etc., and impurities are organic substances and inorganic substances. And objects such as microorganisms, metal objects, non-metal objects, soil, radioactive materials, metal ions, etc. In particular, divalent iron ions such as ferrous sulfate and alkali are added to raw water containing heavy metal ions to coprecipitate heavy metal ions with the precipitate of ferrous hydroxide, and then oxidized with air to precipitate the precipitates with ferrite. Turn into. This ferritization allows the heavy metal to be magnetically separated. In this case, if the purpose is to separate only the heavy metal ions, the aggregating agent becomes unnecessary. So, in this case,
As a pretreatment, ferrous sulfate, an alkaline solution and air are injected into the raw water and treated in a stirring tank, and then the pretreated water may be introduced to the magnetic separation unit.

[0025]

EFFECTS OF THE INVENTION According to the present invention, there is an effect that a separated substance composed of magnetic flocs can be separated and concentrated from the backwash drainage without providing a magnetic field generating means separate from the purifying magnetic separation portion.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a purification system including a magnetic separation device for water purification according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a purification system including a magnetic separation device for water purification according to another embodiment of the present invention.

[Explanation of symbols]

 1 Reservoir 3 Filter 4 Pump 4 5 Raw Water Storage Tank 6 Raw Water 7 Chemical Conditioning Device 7 (Magnetic Powder, Coagulant) 9 Stirring Tank 11 Stirrer 15a Purification Magnetic Separation Container 15b Concentrated Magnetic Adsorption Container 16 Air-Core Coil 17 DC Power Supply Device 18a, 18b Porous magnetic pole 19 Yoke 20a, 20b High gradient magnetic filter 23 Treated water storage tank 26 Air tank 29a Backwash drainage storage tank 29b Concentrated drainage storage tank 30 Concentrated magnetic adsorption container 31 Magnetic field gradient generating cylinder 33 Scraping screw

Claims (6)

[Claims] 1. A magnetic water for purifying water for purifying raw water containing magnetic flocs obtained by adding magnetic powder and a flocculant to raw water containing a pollutant and aggregating the pollutant with the magnetic powder by the flocculant. In the separation device, a first magnetic container into which raw water containing magnetic flocs is introduced from below, an electromagnetic coil provided along an outer peripheral side surface of the first magnetic container, and a first magnetic container loaded into the first magnetic container to form raw water. A first magnetic filter that adsorbs magnetic flocs containing the same, a treated water reservoir that stores raw water discharged from the upper portion of the first magnetic container as treated water, and a first magnetic filter that uses the treated water from the treated water reservoir. Backwash drainage tank for storing backwash drainage discharged when backwashing the magnetic flocs adsorbed on the second magnetic container, and a second magnetic container provided with the first magnetic container and the first magnetic filter penetrating in the vertical direction. And load it into the second magnetic container And a second magnetic filter that adsorbs magnetic flocs contained in the backwash wastewater sent from the backwash wastewater storage tank, and the backwash wastewater and the treated water supplied to the second magnetic filter have the second magnetic property. Water purification, characterized in that the magnetic flocs introduced from the upper part of the container and adsorbed to the second magnetic filter are washed out with the treated water from the treated water storage tank to obtain concentrated drainage with high concentration of magnetic flocs from the backwash drainage. Magnetic separator. 2. When the raw water containing magnetic flocs is introduced into the first magnetic container, backwash drainage is introduced into the second magnetic container at the same time to obtain the treated water and the concentrated drainage. The magnetic separation device for water purification according to claim 1. 3. A magnetic water for purifying water for purifying raw water containing magnetic flocs obtained by adding magnetic powder and an aggregating agent to raw water containing a pollutant and aggregating the pollutant with the magnetic powder by the aggregating agent. In a separation device, a first magnetic container into which raw water containing magnetic flocs is introduced from below, an electromagnetic coil surrounding the outer peripheral side surface of the first magnetic container, and raw water contained in the first magnetic container A magnetic filter that adsorbs magnetic flocs, a treated water tank that stores the raw water discharged from the upper part of the raw water of the magnetic container that passes through the magnetic filter, and a magnetic floc that is adsorbed on the magnetic filter using the treated water from the treated water storage tank. The backwash drainage storage tank that stores backwash drainage discharged when backwashing the water, and the rotary scrub that is disposed between the first magnetic container and the electromagnetic coil to scrape out magnetic flocs from the backwash drainage from the backwash drainage storage tank. A second magnetic container in which a magnetic field gradient generating cylinder that covers the outer peripheral surface of the second magnetic container and is formed by alternately stacking an annular ferromagnetic material and a non-magnetic material is provided. A magnetic separation device for water purification characterized by the above. 4. When the raw water containing magnetic flocs is introduced into the first magnetic container, backwash drainage is introduced into the second magnetic container at the same time to generate the treated water and scrape out the magnetic flocs. The magnetic separation device for water purification according to claim 3, wherein 5. The backwash drainage is supplied from the upper part of the second magnetic container, and the rotary screw scrapes upward the magnetic flocs adhering to the inner wall surface of the second magnetic container. Magnetic separator for water purification. 6. A magnetic floc produced by adding magnetic powder and a flocculant to raw water containing a pollutant and aggregating the pollutant with the magnetic powder by the flocculant is placed in a magnetic field generated by a magnetic field generating means. In a magnetic separation apparatus for water purification for separating water from water by a first magnetic separation unit having a first magnetic adsorption means arranged, a backwashing means for backwashing the first magnetic adsorption means and a backwashing means for backwashing the first magnetic adsorption means. A second magnetic separation part having a second magnetic attraction means arranged in a magnetic field space generated by the magnetic field generation means by filtering wastewater containing magnetic flocs discharged from the first magnetic separation part; The washing water is passed through the magnetic separation part of the second
And a cleaning means for discharging the magnetic flocs accumulated in the magnetic adsorption means at a higher concentration than the wastewater discharged from the first magnetic separation section.