JP2001046912A - Electrode for electrostatic separation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode for an electrostatic separation device capable of screening the particles having the size which had been considered to be difficult to screen and excellent in durability. SOLUTION: In the electrode, a corona generating electrode 1 is placed opposite to a drum electrode 2. In this case, a cord-like corona generating electrode 1 in which many electrode projecting parts are formed at the side surface by twisting plural Nichrome (R) wires is disposed opposite to a longitudinal side surface of the drum electrode 2. The corona generating electrode 1 is provided by twisting two Nichrome (R) wires having 0.1 to 0.7 mm size, and forms the electrode projecting parts by twisting in 2 to 10 mm distance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an electrode used for an electrostatic separation device, and more particularly, to an electrostatic discharge device capable of obtaining a high discharge effect over a wide area of a drum electrode surface by opposing the electrode. The present invention relates to an electrode for a separation device.

[0002]

2. Description of the Related Art Conventionally, an electrostatic separation device for separating mixed different materials such as metal and plastic has been used.

A conventional electrostatic separation device has a corona generating electrode arranged at an appropriate distance from a rotating drum electrode.
When a voltage is applied to the corona generating electrode, a corona discharge phenomenon occurs, and an ionosphere having ion electrons is formed between the corona generating electrode and the drum electrode. The nonconductive material that has passed through the ionosphere is charged, but the conductive material such as metal is not charged and is blown off by the centrifugal force generated by the rotation of the drum electrode. As a result, no electrostatic force is generated and the drum is separated from the drum electrode surface. On the other hand, an insulator such as plastic polarizes when passing through the ionosphere, for example, gives a negative appropriate charge to the corona generating electrode, and when the drum electrode is grounded, corona discharge occurs, and negative ion electrons fill the space. As a result, a negative ion layer is formed. The non-conductive surface passing therethrough is adsorbed on the drum electrode along the flow of the negative ions, and the negative ions eventually flow to the ground via the drum electrode.
As a result, an electrostatic force is generated in the charged insulator and is attracted to the drum electrode. An electrostatic separator separates a conductive material from an insulating material using such an action.

[0004] In this electrostatic separation device, various improvements for separating different kinds of materials have been conventionally proposed. For example, in the electrostatic separation device described in Japanese Patent Application Laid-Open No. 7-178351, the discharge action of the electrode is intended to be enhanced by using a needle-shaped electrode as the corona generating electrode facing the drum electrode.

[0005] In addition to a needle-shaped electrode, a band-shaped electrode having a knife edge shape is used as the corona generating electrode.

[0006]

The discharge action of the electrode depends on the area of the electrode, the voltage applied to the electrode, the distance between the electrode and the drum electrode, the drying condition of the air where the ionosphere is formed, and the like. On the other hand, the separation ability of the electrostatic separation device tends to be difficult to separate as the diameter of the particles of the material to be separated increases, and the pulverizing cost tends to increase as the particle of the material decreases. When using corona generating electrodes of various shapes so far, the diameter of separable particles is limited to at most 1 mm, and if the particles of the material to be selected are larger than this, for example, needle-shaped electrodes or strip-shaped Separation was not possible using electrodes.

In addition, since the corona discharge occurs from the tip of the needle electrode, the tip is severely consumed, leaving a problem in the durability of the needle electrode.

[0008] Further, in the case of the strip-shaped electrode, there is a disadvantage that the production cost of the corona-generating electrode is increased, for example, the electrode is plated with gold or an expensive material is used.

Accordingly, the present invention has been made to solve the above-mentioned problems, and it has become possible to select particles having a size which has been difficult so far, and the voltage applied to the corona generating electrode is lower than in the prior art. It is an object of the present invention to provide an energy-saving type electrode capable of separating metals by a voltage and having excellent durability, and an electrode for an electrostatic separation device.

[0010]

In order to achieve the above object, a first means of the present invention is to provide an electrode for an electrostatic separation device in which a corona generating electrode 1 is opposed to a drum electrode 2, a plurality of nichrome wires 1A. And a large number of electrode protrusions 1 on the side.
It is to provide a corona generating electrode 1 in the form of a string formed with B, and to dispose the corona generating electrode 1 so as to face the longitudinal side surface of the drum electrode 2.

Further, the corona generating electrode 1 of the second means comprises:
Two 0.1-0.7mm nichrome wires 1A are provided close to each other.

Further, the corona generating electrode 1 of the third means is
Forming the electrode projections 1B at a distance of 2 to 10 mm is a means for solving the problem.

According to the present invention, a corona generating electrode 1 in the form of a string is provided.
The corona discharge is widely and uniformly applied to the surface of the drum electrode 2 from the large number of electrode projections 1B provided on the side surfaces of the drum electrode 2.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

Reference numeral 1 shown in the drawing denotes a corona generating electrode.
The corona generating electrode 1 is provided with a plurality of nichrome wires 1A brought close to each other, and has a large number of electrode projections 1B formed on the side surface (see FIG. 2). Corona generating electrode 1 in the illustrated example
Has two nichrome wires 1A close to each other. As the thickness of the nichrome wire 1A decreases, the ionization in the ionosphere formed by corona discharge increases, but on the other hand, the strength of the nichrome wire 1A decreases, which limits the practical range. Thus, it was experimentally found that by setting the thickness within the range of 0.1 to 0.7 mm, an effective corona discharge action was obtained and the durability was high.

FIG. 1 shows that a corona generating electrode 1 is connected to a drum electrode 2.
2 shows a state in which they face each other. Although the corona generating electrode 1 in the illustrated example shows one corona generating electrode 1 for convenience, a plurality of corona generating electrodes 1 may be used. still,
Reference numeral 4 shown in the figure indicates that when the corona generating electrode 1 is cut,
A resistor for preventing a short-circuit large current, and reference numeral 5 denotes an insulator.

The electrode projection 1B of the corona generating electrode 1 is a projection formed when the nichrome wire 1A is brought close.
When the corona generating electrode 1 is arranged along the longitudinal direction of the drum electrode 2, a corona discharge is generated from the electrode protrusion 1B facing the drum electrode 2 side. As a result, a uniform ionosphere is generated over a wide range along the longitudinal side surface of the drum electrode 2. In order to obtain an effective corona discharge action, the interval between the corona generating electrodes 1 is preferably 2 to 10 mm.

FIG. 3 shows a separation experiment using an electrostatic separation device using the electrode of the present invention. This experiment was performed by arranging two corona generating electrodes 1 and one induction electrode 3 in parallel along the longitudinal side surface of the drum electrode 2. The corona generating electrode 1 is a nichrome wire having a diameter of 0.2 mm,
Those that were aligned at 3 mm intervals were used.

The numerical values of L1 to L5 shown in Table 1 indicate the distance (mm) of the corona generating electrode 1 shown in FIG. 3, and the corona generating electrode 1 is arranged corresponding to each material. In addition, the secondary voltage indicates a voltage applied to the corona generating electrode 1, and in Table 1, it is 11.6-16.4 KV.

[0020]

[Table 1] The materials (inputs) shown in Table 2 used three types of mixtures (I) to (III). Material (I) is plastic,
Aluminum and copper are crushed into particles of 3 mm or less, and the mixing ratio is
80:10:10 mixture. Material (II) is wood,
Plastic, aluminum and copper crushed into particles of 3 mm or less each and mixed at a mixing ratio of 40:40:20. For the material (III), a printed circuit board crushed into particles of 3 mm or less was used.

[0021]

[Table 2] Table 3 shows the collection results (collection amount) of each material. In Table 3, column A indicates the amount of recovered plastic (g), column B indicates the amount of recovered mixture (g), and column C indicates the amount of recovered metal (g).

[0022]

[Table 3] As a result of the above experiments, it is shown that the use of the electrode of the present invention can sufficiently separate even a material having a particle diameter of 3 mm, which has heretofore been impossible. The secondary voltage applied to the corona generating electrode 1 is in the range of about 10 to 20 KV, and it is shown that the voltage can be sorted by about 1/2 of the conventional secondary voltage. Proven.

[0023]

According to the present invention, the above object has been attained.

That is, the corona generating electrode 1 according to the present invention provides a wide and uniform discharge effect on the drum electrode, and makes it possible to sort particles having a size that has been considered difficult. Was.

The corona generating electrode 1 according to claim 2
As a result, the durability is increased by a factor of ten compared to, for example, a linear corona generating electrode of 0.2 mm 2.

Furthermore, the corona generating electrode 1 according to claim 3
As a result, a wide and stable discharge effect can be obtained even at a voltage lower than the voltage of the conventional corona generating electrode, and it has become possible to sort particles having a diameter of 3 mm, which was difficult in the past.

As described above, according to the present invention, it is possible to sort large particles, which has been considered difficult, and it is possible to reduce the energy consumption by using a voltage much lower than the conventional voltage. It has various industrially beneficial effects such as excellence.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a main part showing a use state of the present invention.

FIG. 2 is an enlarged view of a main part showing an embodiment of the electrode of the present invention.

FIG. 3 is a side view showing an experimental state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Corona generating electrode 1A Nichrome wire 1B Electrode convex part 2 Drum electrode 3 Induction electrode 4 Resistance 5 Insulator

Continued on the front page (72) Inventor Anatoly I. Messenyasin St. Petersburg, Russia, 199109, Building 8A, 21 Linear, Vasilyevskaya Austrov Ak Zionnernoye Obshestovo Me Hanover Technica F-term (reference) 4D054 GA01 GA04 GB01 GB09 GB09

Claims (3)

[Claims] 1. An electrode for an electrostatic separation device in which a corona generating electrode is opposed to a drum electrode, a string-shaped corona generating electrode having a plurality of electrode projections formed on a side surface by bringing a plurality of nichrome wires close together. An electrode for an electrostatic separation device, wherein a corona generating electrode is provided so as to face a longitudinal side surface of a drum electrode. 2. The electrode for an electrostatic separation device according to claim 1, wherein said corona generating electrode is provided with two nichrome wires of 0.1 to 0.7 mm close to each other. 3. The electrode for an electrostatic separation device according to claim 1, wherein the corona generating electrodes are formed so as to protrude from each other at intervals of 2 to 10 mm.