JPH0677657B2 - Magnetic separation device - Google Patents

Description

The present invention relates to a magnetic separator for separating magnetic particles contained in raw water.

(Prior Art) Magnetic separation technology has been used as a method for efficiently selectively separating and concentrating and removing a magnetic material from a mixture of minute magnetic materials or magnetic materials and non-magnetic materials dispersed in a liquid. It is used. This technology includes, for example, Tomio Nagashima, Vol. 45, No. 4 (1981), pages 226 to 233,
In particular, page 231, Figure 10, Figure 11, and Seientifie American November 197.
Page 5,47 to 52, especially page 48 The figure below, the figure on page 52, the figure on page 53, the magnetic element as shown in the figure on page 53 moves continuously while operating, and attracts magnetic elements in raw water and elements outside the magnetic field. There are a magnetic separation device having a structure in which cleaning is repeated, and a magnetic separation device which performs element cleaning by performing reverse cleaning when the adsorption capacity of an element that has been statically placed in a magnetic field is saturated. By the way, the structure of the element that has been adopted in these magnetic separation devices is such that the entire element is integrated and moves in the same manner. For example, Chemical Engineering Vol. 45, No. 4, by Tomio Nagashima (198
1) On page 231 Figure 10 usually has a certain height (about 20 cm)
The expanded metals are stacked and arranged in a ring shape, the whole element is integrated and continuously rotated in the magnetic field, the raw water is continuously supplied to the element part in the magnetic field, and the element is outside the magnetic field. Is to be washed. See also Scientific American (Seientif
ic American) November 1975, the example of the magnetic separation device shown in the figure on page 53 is almost the same in principle. On the other hand, Scientific American (Seientific A
merican) November 1975, page 48 In the examples of the magnetic separators shown in the figures below and on page 52, the elements are statically placed in a magnetic field and the element is washed when saturated by cutting off the magnetic field and applying high pressure water etc. from the opposite direction. Has been done. In order to enhance the magnetic substance adsorption capacity of the magnetic separation device, the distance of the element portion through which the raw water passes is increased, that is, the height of the element is increased, and further, the filling rate of the element is increased, wool, fine wire, etc. It is used by packing elements with a fine shape such as.

2 to 5 show examples of magnetic separators and their elements that have been widely used conventionally. FIG. 2 shows a structure in which an element 12 made of expanded metal, for example, is densely packed in a ring-shaped case 13. The electromagnet 11 is installed in contact with a part of the peripheral surface of the container 13, and the raw water 14 is fed into the container 13 in proximity to the electromagnet 11 while rotating the container 13. The cleaning of the element 12 is performed by the cleaning water 15 introduced outside the magnetic field. FIG. 3 shows a structure in which the case 13 filled with the element 12 is reciprocated in and out of the magnetic field. The principle is the same as that of FIG. 2, and in both cases, the cleaning of the element is performed outside the magnetic field. Fig. 4 shows a coil
Case 23 in the strong magnetic field space at the end of yoke 22 magnetized by 21
Is installed on the surface of the element 24.
It is a structure that allows 25 to flow in. Further, FIG. 5 shows that the element 33 such as a thin wire or wool is densely filled and set in the strong magnetic field space of the yoke 32 magnetized by the coil 31.
This is a structure in which the raw water 34 flows in until it becomes saturated. Figure 4,
In the structure shown in FIG. 5, the raw water is stopped when the element is saturated, and the element is backwashed with fresh water. As shown in FIGS. 2 to 5, the conventional magnetic separation element is shown in FIG.
As shown in FIG. 3, the element is constantly rotating or reciprocating, but the whole element is of the integral type,
As shown in Fig. 5 and Fig. 5, it is roughly divided into those of the type that does not have such movement.

(Problems to be solved by the invention) However, in any method, when raw water flows in, even if a magnetic substance or a small amount of non-magnetic substance in the raw water is adsorbed in the element, it is very difficult to wash it off. is there. Second
As shown in Fig. 3 and Fig. 3, even if high-pressure washing water is flown from above, the pressure drops inside the element, and the washing water pressure at the bottom of the element becomes close to the water's own weight, and the washing power becomes extremely small. . The element in FIGS. 2 and 3 is constantly in motion because it is constantly moving, but it is still difficult to clean the entire element and clogging progresses. Especially in the case of Fig. 4 and Fig. 5, it is difficult to wash because the raw water is poured until the element is almost saturated. Especially, it is difficult to wash fine wires and wool, and clogging progresses fairly quickly, and both are due to insufficient washing. There is a drawback that the adsorption capacity of the magnetic material is reduced.

An object of the present invention is to provide a magnetic separation device which eliminates the above-mentioned conventional drawbacks, efficiently cleans the element, and maintains a high magnetic substance adsorption capacity.

(Means for Solving Problems) According to the present invention, magnetic elements are installed in a plurality of upper and lower stages while maintaining a constant interval, and the vertically adjacent elements are moved in opposite directions. This is a magnetic separation device characterized by the above.

The present invention will be described below with reference to FIG.

Reference numeral 1 is a magnet that forms a magnetic field space within a certain area. The magnet 1 may be either a permanent magnet or an electromagnet.
According to the present invention, a plurality of element units 2, 2, ... In which elements 3 such as wool and fine wires are packed in a case straddling the inside and outside of this magnetic field space are installed in a plurality of upper and lower stages while being kept at a constant interval, Each adjacent unit 2,2, ...
Is interlocked with drive devices 4a and 4b that give the moving feeds in the opposite directions. A raw water supply port 5 is provided above the magnetic field space, that is, the magnet 1, and a raw water drainage port 6 is provided below it.
And a cleaning water supply port 7 and a discharge port 8 for cleaning the element 3 in each unit 2, 2, ... Outside the area of the magnetic field space.
Are arranged corresponding to the top and bottom. In the method of reciprocating the unit 2 to the left and right, a set of wash water supply port 7 and discharge port 8 is installed on the left and right sides of the magnetic field space. Therefore, in this method, although the advance / retreat drive device is used for the drive devices 4a and 4b, the drive device 4a, 4b is not necessarily limited to this, and the rotary drive device may be used for application to the type shown in FIG.

(Operation) The element units 2, 2, ... Which are vertically adjacent to each other with a certain distance maintained in the magnetic field space always reciprocate in the opposite directions, so that the ends of the element units in each stage constantly move in the opposite directions. Raw water 9 enters in the state of being
Washed by 10. At this time, since the adjacent ends of the element units move in the opposite directions, a state close to mechanically disturbing the inside of one seemingly long one element unit is realized. Moreover, since a magnetic field gradient larger than that in the inside is generated at the end of the element unit, a large magnetic attraction force is realized at the adjacent end face. It is obvious that such an element has exactly the same effect not only in the conventional reciprocating magnetic separation device of FIG. 3 but also in the rotary magnetic separation device of FIG. Further, although the case where the adjacent elements always perform mutually opposite motions has been described, intermittent motions are also effective. Alternatively, exercising only during washing is also effective.

(Effects of the Invention) As described above, according to the present invention, the cleaning of the element is performed very effectively by supplying the cleaning water while moving the upper and lower multi-stage element units in the opposite directions. Can be done, and 2 elements
Since it is divided into the above and unitized, the element can be easily cleaned compared with the case where the element is housed in one container as in the conventional case.

(Examples) Examples of the present invention will be shown below.

Using the apparatus of the present invention shown in FIG. 1 and the conventional reciprocating magnetic separation apparatus shown in FIG. 3, the magnetic separation treatment of the CRT glass polishing wastewater is carried out in the continuous operation day and night, and the clogging start time of the element is started. And the removal rate of the magnetic substance (iron powder in this case) was measured. Table 1 shows SS (Suspended Solid)
Table 2 shows the operating conditions. The clogging start time was measured as the time when raw water began to overflow from the element.
The measurement results are shown in Table 3.

However, the abrasive is composed of pumice, alundum and cerium oxide.

According to the operating conditions shown in Table 2, as a result of a test of about 105 days of continuous operation, the element of the device of the present invention is less likely to be clogged, and in addition, an element having a high magnetic substance adsorption ability can be obtained.
Efficient magnetic separation was achieved. However, it has been found that the size of the adjacent gap of the multi-stage element of the present invention is related to the applied magnetic field and is normally about 30 mm or less.

[Brief description of drawings]

FIG. 1 is a sectional view of a magnetic separator according to the present invention, FIG. 2 is a perspective view of a conventional rotary magnetic separator, FIG. 3 is a sectional view of a conventional reciprocating magnetic separator, and FIG. FIG. 5 is a perspective view of a magnetic separator having the wavy element of FIG. 5, and FIG. 5 is a sectional view of a conventional high gradient magnetic separator. 1 ... Magnet, 2 ... Element unit, 3 ... Element, 4a, 4b ... Driving device, 5 ... Raw water supply port, 6 ...
Raw water drainage port, 7 ... washing water supply port, 8 ... washing water drainage port, 9 ... raw water, 10 ... washing water.

Claims (1)

[Claims] 1. A ferromagnetic element, means for applying a magnetic field to the element, a supply port for supplying raw water containing a magnetic material to the element part to which the magnetic field is applied, and a lower side of the supply port. There is a drain port for discharging raw water that has passed through the element portion to which a magnetic field is applied, a supply port for supplying element cleaning water to the element portion to which the magnetic field is not applied, and a lower side of the cleaning water supply port. In a magnetic separation device having a drain outlet for receiving the cleaning water after the cleaning,
A plurality of units filled with the elements are installed in a multi-tiered manner while being held at a constant interval, and vertically adjacent element units are interlocked with driving devices that respectively give a moving feed in opposite directions. And a magnetic separation device.