JPH11156719A - Wire saw abrasive grain regeneration method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently separate used abrasive grain slurry into abrasive grains and cutting fluid to recover each of them for using them again. SOLUTION: Abrasive grain slurry 3' used for a wire saw 1 is led to a first centrifugal separator 20 so as to be separated into recovered abrasive grains 5' and very small grain mixture fluid 23 containing very small cutting chips, after very small solid bodies in the very small grain mixture fluid 23 have been increased in diameter by letting the very small grain mixture fluid 23 pass through a high density electric field, the very small solid bodies are led to a second centrifugal separator 25 so as to be separated into increased diameter very small solid bodies 26 and recovered cutting chip fluid 6', and the recovered abrasive grains 5' separated by the first centrifugal separator 20 and the recovered cutting chip fluid 6' separated by the second centrifugal separator 25, are mixed so as to be reused as abrasive grain slurry.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for regenerating a wire saw abrasive slurry capable of circulating and using abrasive grains of a wire saw for cutting or cutting a silicon wafer or the like.

[0002]

2. Description of the Related Art Conventionally, a wire saw has been used as an apparatus for cutting a silicon wafer or the like.

[0003] A wire saw is used for a wire moving at high speed.
Abrasive grains (particle size =
A wire that moves an abrasive slurry obtained by mixing a cutting fluid (usually a mixture of mineral oil and water and various additives) with a cutting fluid (typically, mineral oil mixed with water and various additives). To cut a silicon wafer or the like.

FIG. 3 is a block diagram showing a supply path of abrasive slurry used in the above-mentioned conventional wire saw. In the drawing, reference numeral 1 denotes a wire saw provided with a wire (not shown) for cutting a silicon wafer or the like. The abrasive slurry 3 from the slurry supply device 2 is supplied to the wire saw 1.

The slurry supply device 2 includes a slurry supply tank 4
A new abrasive 5 and a new cutting liquid 6 are metered and supplied to the slurry supply tank 4 so as to have a required ratio, and the slurry is stirred by a stirrer 7 to thereby obtain a uniform concentration of abrasive. A slurry 3 is generated, and the slurry supply tank 4
A supply pipe 9 provided with a supply pump 8
Supply to the upper part of the wire saw 1 by the supply valve 1
0 is supplied to the wire saw 1 by a downward supply pipe 11 provided with a zero and a return pipe 12 connects a position before the supply valve 10 in the supply pipe 9 and the slurry supply tank 4. When the supply valve 10 is closed, the abrasive slurry 3 is circulated to prevent the abrasive 5 from settling in the supply pipe 9.

Further, the used abrasive slurry 3 ′ containing cutting chips and crushed abrasive particles is supplied to the wire saw 1 and used for cutting, and the discharged slurry 13 ′
Is supplied to a waste treatment device 15 through a discharge pipe 14 provided with

[0007] In the waste treatment apparatus 15, the used abrasive slurry 3 'is introduced, and solid waste 16 composed of abrasive grains, crushed particles thereof and cutting chips, and liquid waste 17 composed of cutting liquid are introduced. The solid waste 16 and the liquid waste 17 are respectively treated as waste.

However, in the conventional method shown in FIG. 3, since the abrasive slurry 3 is disposable, it is necessary to always supply a new expensive abrasive 5 and a new cutting fluid 6, and the operating cost is increased. Had the problem of increasing. In addition, there is a problem that the amount of the solid waste 16 and the liquid waste 17 is increased, which poses a problem of environmental protection, and that the cost for the disposal of the waste increases.

In order to cope with this problem, as a method of recovering abrasive grains and cutting liquid from the used abrasive slurry 3 'and repeatedly using them, a centrifugal separator may be provided in two stages,
Alternatively, a mechanical / physical separation method combining a centrifuge and a filtration membrane has been proposed.

[0010]

However, the efficiency of separation by centrifugal force is proportional to the square of the particle size of the dispersed particles and the density difference (specific gravity difference) between the dispersed particles and the dispersion solvent (liquid). It is known that the particle size is very small (several microns) like silicon wafer chips,
In addition, it is difficult to efficiently separate cutting chips having a small difference in specific gravity with respect to the abrasive grains and the cutting liquid using a centrifugal separator.

[0011] Separation using a filtration membrane also tends to cause clogging of the membrane due to the high viscosity of the abrasive slurry after use (150 to 200 cp) and the small particle size of the cuttings, and the processing amount is small. In view of this, there are many problems when used in a continuous production line.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the conventional method, and efficiently separates and recovers abrasive grains and cutting liquid from used abrasive slurry and reuses them. It is an object of the present invention to provide a method and an apparatus for regenerating a wire saw abrasive slurry capable of minimizing the amount of use of a new abrasive and a new cutting fluid and significantly reducing the amount of waste generated. .

[0013]

According to the first aspect of the present invention, a used abrasive slurry used for a wire saw is guided to a first centrifugal separator, and the collected abrasive grains, fine chips and crushed abrasives are collected. After separating the fine-grained mixed liquid containing fine particles into the fine-grained mixed liquid and passing the finely-grained mixed liquid through a high-density electric field to increase the particle size of the fine-grained solid in the fine-grained mixed liquid, Then, the collected abrasive particles separated by the first centrifugal separator and the collected cutting liquid separated by the second centrifugal separator are mixed and re-formed as an abrasive slurry. And a method for regenerating a wire saw abrasive slurry, wherein the method is used.

The second aspect of the present invention is to increase the particle size of the solid particles in the abrasive slurry by passing the used abrasive slurry used in the wire saw through a high-density electric field. It is led to a centrifugal separator to separate the collected abrasive grains and the increased diameter fine particle mixed liquid containing the increased diameter fine particle solid, and further, the increased diameter fine particle mixed liquid is guided to a second centrifuge to recover the increased diameter fine solid. A wire saw, which is separated into a cutting liquid, and the recovered abrasive particles separated by the first centrifuge and the recovered cutting liquid separated by the second centrifuge are mixed and reused as an abrasive slurry. A method of regenerating abrasive slurry.

[0015] According to a third aspect of the present invention, there is provided a first method of introducing used abrasive slurry from a wire saw to separate recovered abrasive grains and a fine grain mixed liquid containing fine cutting chips and crushed abrasive grains. A centrifugal separator; a high-density electric field generator for applying a high-density electric field to the fine-particle mixed liquid separated by the first centrifuge to increase the particle size of fine solids in the fine-particle mixed liquid; A second centrifugal separator that separates the recovered cutting liquid from the increased-fine-grained solid whose particle size has been increased by the electric field generator, the recovered abrasive particles separated by the first centrifuge, and the second centrifuge A wire saw abrasive grain, comprising: a slurry supply device that introduces a recovered cutting fluid separated by a separator and introduces a new abrasive grain and a new cutting fluid to supply an abrasive slurry to a wire saw. An apparatus for regenerating a slurry.

According to a fourth aspect of the present invention, there is provided a high-density electric field generator for increasing a particle diameter of solid particles in an abrasive slurry by applying a high-density electric field to a used abrasive slurry from a wire saw. A first centrifugal separator for introducing an abrasive slurry containing solid particles whose particle diameter has been increased by a high-density electric field generator to separate collected abrasive particles and a mixed liquid of increased diameter fine particles; A second centrifugal separator that separates the enlarged fine solid and the recovered cutting liquid from the enlarged fine mixed liquid separated by the separator, and the collected abrasive particles separated by the first centrifuge and the second centrifugal separator. And a slurry supply device for introducing the recovered cutting liquid separated by the centrifugal separator and introducing new abrasive grains and a new cutting liquid to supply an abrasive slurry to the wire saw. Apparatus for regenerating abrasive slurry A.

According to a fifth aspect of the present invention, there is provided a foreign matter removing apparatus for removing foreign matter by introducing a collected abrasive grain separated by a first centrifuge and a collected cutting liquid separated by a second centrifuge. An apparatus for regenerating a wire saw abrasive slurry according to claim 3 or 4, further comprising an apparatus.

According to the above-mentioned means, the operation is as follows.

According to the first and third aspects of the present invention, the used abrasive slurry is separated into the recovered abrasive particles and the fine particle mixed liquid by the first centrifugal separator. The separated fine liquid mixture is guided to a high-density electric field generator and passed through a high-density electric field to increase the particle size of the fine solids in the fine liquid mixture to obtain an increased-diameter fine liquid mixture. The diameter-fine mixed liquid is guided to a second centrifugal separator to separate the diameter-increased fine solid and the recovered cutting liquid, and the recovered abrasive particles and the recovered cutting liquid are guided to a slurry supply device and reused as an abrasive slurry. As a result, the amount of use of expensive new abrasive grains and new cutting fluid can be reduced, and the operating cost can be significantly reduced.

According to the second and fourth aspects of the present invention, the used abrasive slurry is guided to a high-density electric field generator and passed through a high-density electric field, whereby the particles of the solid particles in the abrasive slurry are removed. After increasing the diameter, the mixture is guided to a first centrifugal separator to separate the collected abrasive grains and an increased-fine-grained mixed liquid containing an increased-sized fine-grained solid, and further separates the increased-aperture / fine-grained mixed liquid into a second centrifugal separator. To separate into the increased diameter fine solid and the recovered cutting liquid, and the recovered abrasive particles and the recovered cutting liquid are guided to a slurry supply device so as to be used again as an abrasive slurry.
By reducing the amount of expensive new abrasive grains and new cutting fluids used, operating costs can be significantly reduced.

According to the first to fourth aspects of the present invention, the enlarged solids are separated by a centrifugal separator from the enlarged mixed liquid in which the solids are enlarged. Fine particles in the abrasive slurry can be effectively separated. Furthermore, the amount of the enlarged solids separated by the second centrifugal separator is very small, so that the amount of waste is reduced, which is advantageous in terms of environmental protection, and the disposal cost is also reduced. It has the effect of being able to reduce.

According to the fifth aspect of the present invention, the foreign matter such as coarse particles in which fine particles are aggregated or cutting debris is separated and removed by the foreign matter removing device for introducing the recovered abrasive grains and the recovered cutting liquid. This has the effect that a uniform and good abrasive slurry can be obtained.

[0023]

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

FIG. 1 is a block diagram showing an embodiment of the present invention. A used abrasive slurry 3 ′ used in a wire saw 1 similar to that shown in FIG. The used slurry is supplied to a used slurry storage tank 18 via a pipe 14. The used slurry storage tank 18 is provided with a stirrer 19 and used abrasive slurry 3 ′
Is prevented from settling.

In FIG. 1, reference numeral 20 denotes a first centrifugal separator.
The used abrasive slurry 3 ′ in 8 is introduced through an introduction pipe 22 equipped with a pump 21, and the used abrasive slurry 3 ′ is collected with the collected abrasive 5 ′, cutting chips and The liquid is separated from the fine particle mixed liquid 23 containing crushed abrasive particles.

The used abrasive grain slurry 3 ′ is composed of recovered abrasive grains 5 ′ having a particle size substantially equal to that of the new abrasive grains 5 (about 18.5 to 21.5 μm) and about several microns. Cutting chips having a size and crushed abrasive grains crushed to a size of about several microns are in a mixed state.

As the first centrifugal separator 20, for example, a decanter type centrifuge is used.
0-500G), the collected abrasive grains 5 '
And a fine particle mixed liquid 2 containing other cutting chips and crushed abrasive grains
3 can be effectively separated. In addition, the first
In addition to the decanter-type centrifugal separator, a liquid cyclone or the like can be used as the centrifugal separator 20.

In FIG. 1, reference numeral 24 denotes a high-density electric field generator for applying a high-density electric field to the fine-particle mixed liquid 23 to increase the particle size of the fine solids in the fine-particle mixed liquid 23.

The electric energy is pulsed (30 to 60 pulses / sec) in a short time (1/1000 to 100/1000).
Sec.) In a high-density electric field (5000 to 2500
It is known that passing a solid-liquid dispersion through a solid-liquid dispersion can increase the particle size of the solid particles in the dispersion (US Pat. No. 4,957,60).
6).

Therefore, if the high-density electric field generator 24 that can increase the particle size of the solid particles existing in the liquid dispersion system by using the electron energy is used,
3 can be a mixed liquid 23a having an increased particle diameter of fine cutting chips and crushed abrasive solid particles.

Downstream of the high-density electric field generator 24,
Is provided, and the diameter-increased fine-particle mixed liquid 23a from the high-density electric field generator 24 is introduced, and the diameter-increased fine-particle mixed liquid 23a is increased in diameter by increasing the particle diameter of solid particles. The fine solid 26 is separated into the recovered cutting liquid 6 ′.

The used abrasive slurry 3 ′ has a relatively high viscosity as described above, and therefore, from the finely mixed liquid 23 having such a high viscosity, cutting chips and crushed abrasive particles of about several microns are obtained. Although it is not easy to separate the particles, if the high-density electric field generator 24 can increase the particle size of solid particles of several microns, for example, several times, about 3000 G can be given to the fine particle mixed liquid 23. When separation is performed using a decanter-type centrifugal separator, an increased-diameter solid 26 composed of cutting chips and crushed abrasive grains, and a recovered cutting liquid 6 ′
And can be separated effectively. Further, as the second centrifugal separator 25, besides the decanter type centrifuge, a separation plate type centrifuge can be used.

In FIG. 1, reference numeral 28 denotes a foreign matter removing device. The foreign matter removing device 28 introduces the collected abrasive grains 5 ′ separated by the first centrifugal separator 20, while the second centrifugal separator 2
The collected cutting liquid 6 ′ separated in 5 and stored in the collected cutting liquid storage tank 27 is introduced by a collected liquid supply pipe 30 provided with a pump 29, and fine particles in the collected cutting liquid 6 ′ are aggregated. The foreign matter 31 such as the coarse particles grown and the cutting fragments mixed with the collected abrasive grains 5 'is separated, and a mixed slurry 32 composed of the collected abrasive grains 5' and the collected cutting liquid 6 'can be taken out.

A wet sieving device (vibrating sieving device) is used as the foreign matter removing device 28 so that the collected abrasive grains 5 ′ separated by the first centrifugal separator 20 can be removed from the second centrifugal separator 25. The foreign matter 31 can be effectively separated while being washed with the recovered cutting liquid 6 ′ from the recovered cutting liquid storage tank 27 separated by the above.

The mixed slurry 32 from the foreign matter removing device 28 is supplied to a slurry supply tank 4 of the slurry supply device 2, and a new abrasive 5
And the new cutting liquid 6 are metered and supplied so as to have a required ratio, and the abrasive slurry 3 having a uniform concentration and stirred by the stirring device 7 is supplied to the wire saw 1 by the operation of the supply pump 8. ing.

The operation of the embodiment shown in FIG. 1 will be described below.

As shown in FIG. 1, the abrasive slurry 3 in the slurry supply tank 4 of the slurry supply device 2 is supplied from the supply pump 8 to the wire saw 1 via the supply pipe 9 and the downward supply pipe 11. Cutting of silicon wafers etc. is performed together with wires that are not used.

The used abrasive slurry 3 ′ used in the wire saw 1 is supplied to a used slurry storage tank 18 via a discharge pipe 14 by a discharge pump 13, and used in the used slurry storage tank 18. The subsequent abrasive slurry 3 ′ is supplied to the first centrifugal separator 2 through the introduction pipe 22 by the pump 21.
0 is introduced.

The used abrasive slurry 3 ′ introduced into the first centrifugal separator 20 is separated by giving 300 to 1000 G by a centrifugal effect of a decanter type centrifugal separator or the like, whereby the collected abrasive particles 5 ′ are separated. ′ And the fine particle mixed liquid 23 containing cutting chips and crushed abrasive grains are effectively separated.

The electric energy is pulsed (30 to 60 pulses / sec) in a short time (1/1000 to 100/1000).
Second) to release a high-density electric field (5000-25
000 V / cm) in the high-density electric field of the high-density electric field generator 24, which is formed by the first centrifuge 20, in the high-density electric field generator. 23, the fine particle mixed liquid 2
The cutting chips and crushed abrasive grains in 3 can be increased in diameter to form a mixed liquid 23a with increased diameter.

The enlarged diameter fine particle mixed liquid 23a is introduced into a second centrifugal separator 25 capable of giving about 3000 G by a centrifugal effect by a decanter-type centrifugal separator or the like, thereby de-liquidized enlarged diameter fine particle solids 26a. And the recovered cutting liquid 6 '.

The diameter-increased fine solids 26 which are removed by the second centrifugal separator 25 are about 2 to 3% of the total solids in the abrasive slurry 3, and accordingly, the first centrifugal separation Machine 2
The recovery rate of the collected abrasive grains 5 ′ separated and reused at 0 is
97-98%. Therefore, in the recovered cutting liquid 6 ′ from which the diameter-increased fine solids 26 have been removed, fine particles of about several microns exist, but such fine particles exist in the abrasive slurry 3. Also proved not to be detrimental to the cutting performance of the wire saw 1. In addition, since the fine particles are circulated and used, they are again guided to the high-density electric field generator 24 to be increased in diameter, and the increased-diameter solid particles 26 having increased diameter are separated by the centrifugal separator 25. The concentration of the fine particles in the abrasive slurry 3 is kept substantially constant.

The collected abrasive grains 5 ′ separated by the first centrifugal separator 20 are guided to a foreign matter removing device 28 such as a wet sieving device, and the collected cutting liquid separated by the second centrifugal separator 25. The collected cutting liquid 6 ′ stored in the storage tank 27 is guided to the foreign matter removing device 28 to separate and remove the foreign matter 31 such as coarse particles or cutting shards that have grown due to agglomeration of fine particles, and the collected abrasive particles 5 ′ are collected. Mixed slurry 3 consisting of cutting liquid 6 '
2 is supplied to the slurry supply tank 4 of the slurry supply device 2.

By using a wet sieving device as the foreign matter removing device 28, the collected abrasive grains 5 ′ separated by the first centrifugal separator 20 are collected by the second centrifugal separator 25. While cleaning with the cutting liquid 6 ′,
1 can be effectively separated.

The mixed slurry 32 from the foreign matter removing device 28 is supplied to the slurry supply tank 4 of the slurry supply device 2, and new abrasive grains 5 and new cutting liquid 6 are measured and supplied thereto. As a result, the abrasive slurry 3 having a predetermined concentration can be manufactured. The slurry supply device 2
The abrasive slurry 3 adjusted to a predetermined concentration is supplied to the wire saw 1 by a supply pipe 9 provided with a supply pump 8.

As described above, according to the embodiment of FIG.
The used abrasive slurry 3 ′ is separated into the collected abrasive 5 ′ and the fine particle mixed liquid 23 by the first centrifuge 20, and
Fine particle mixed liquid 23 separated by first centrifuge 20
Is introduced into the high-density electric field generator 24 and passed through the high-density electric field, thereby increasing the particle size of the fine solids in the fine-particle mixed liquid 23 to obtain an increased-fine-particle mixed liquid 23a. 23a is guided to a second centrifugal separator 25 to be separated into an increased-diameter fine-grained solid 26 and a recovered cutting liquid 6 ', and the recovered abrasive grains 5' and the recovered cutting liquid 6 'are guided to the slurry supply device 2 again. Since the slurry is used as the abrasive slurry 3, the amount of use of the expensive new abrasive grains 5 and the new cutting fluid 6 can be reduced, and the operating cost can be significantly reduced.

Further, the amount of the increased-diameter fine solid 26 separated by the second centrifugal separator 25 is very small, so that the amount of waste is reduced, which is advantageous in terms of environmental preservation. In addition, disposal costs can be reduced.

Further, since the foreign matter 31 such as coarse particles or cutting debris in which fine particles are aggregated is separated and removed by the foreign matter removing device 28 for introducing the collected abrasive grains 5 'and the collected cutting liquid 6', it is homogeneous. Good abrasive slurry 3 can be obtained.

FIG. 2 is a block diagram showing another example of the embodiment of the present invention. The same elements as those in FIG. 1 are denoted by the same reference numerals, and different points from FIG. The high-density electric field generator 24 provided between the first centrifuge 20 and the second centrifuge 25 is abolished, and the used slurry from the used slurry storage tank 18 to the first centrifuge 20 is removed. High-density electric field generator 24
It is in the point with.

In the embodiment shown in FIG. 2, the used abrasive slurry 3 ′ from the used slurry storage tank 18 is first guided to the high-density electric field generator 24, and is passed through the high-density electric field. The particle diameter of the solid particles in the slurry 3 ′ is increased, and then the liquid is guided to the first centrifugal separator 20 to collect the collected abrasive particles 5 ′ and the enlarged-fine-particle mixture liquid 23 a containing the increased-fine-particle solid.
Since the diameter-increased fine particle mixed liquid 23a is further guided to the second centrifugal separator 25 so as to be separated into the diameter-increased fine particle solid 26 and the recovered cutting liquid 6 ', the embodiment shown in FIG. In the same manner as described above, the enlarged fine solid 2
6 can be effectively separated, and the recovered cutting liquid 6 'can be effectively recovered.

The present invention is not limited to the illustrated embodiment, and various changes can be made without departing from the gist of the present invention.

[0052]

According to the first and third aspects of the present invention,
The abrasive slurry after use in the first centrifuge is separated into recovered abrasive grains and a fine-particle mixed liquid, and the fine-particle mixed liquid separated in the first centrifuge is sent to a high-density electric field generator. The resulting mixture is passed through a high-density electric field to increase the particle size of the fine solids in the fine liquid mixture to form an increased diameter fine liquid mixture. Further, the increased diameter fine liquid mixture is guided to a second centrifuge. Since the increased-diameter fine-grained solid and the recovered cutting liquid are separated, and the recovered abrasive and the recovered cutting liquid are guided to a slurry supply device and used again as an abrasive slurry, expensive new abrasives and new The amount of cutting fluid used can be reduced, and the operating cost can be greatly reduced.

According to the second and fourth aspects of the present invention, the used abrasive slurry is guided to a high-density electric field generator and passed through a high-density electric field, whereby the particles of the solid particles in the abrasive slurry are removed. After increasing the diameter, the mixture is guided to a first centrifugal separator to separate the collected abrasive grains and an increased-fine-grained mixed liquid containing an increased-sized fine-grained solid, and further separates the increased-aperture / fine-grained mixed liquid into a second centrifugal separator. To separate into the increased diameter fine solid and the recovered cutting liquid, and the recovered abrasive particles and the recovered cutting liquid are guided to a slurry supply device so as to be used again as an abrasive slurry.
The use of expensive new abrasive grains and new cutting fluid is reduced, and the operation cost is greatly reduced.

According to the first to fourth aspects of the present invention, since the enlarged fine solid is separated from the enlarged fine mixed liquid in which the fine solid is increased, the centrifugal separator is used. This produces an effect that fine particles in the abrasive slurry can be effectively separated.

Furthermore, the amount of the enlarged solids separated by the second centrifuge is very small, so that the amount of waste is reduced, which is advantageous in terms of environmental protection, This has the effect of reducing processing costs.

According to the fifth aspect of the present invention, the foreign matter such as coarse particles or cutting chips in which fine particles are aggregated is separated and removed by the foreign matter removing device for introducing the collected abrasive grains and the collected cutting liquid. This has the effect that a uniform and good abrasive slurry can be obtained.

[Brief description of the drawings]

FIG. 1 is a system block diagram illustrating an example of an embodiment of the present invention.

FIG. 2 is a system block diagram showing another example of the embodiment of the present invention.

FIG. 3 is a block diagram showing a supply path of abrasive slurry in a conventional wire saw.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 wire saw 2 slurry supply device 3 abrasive slurry 3 ′ abrasive slurry after use 5 new abrasive 5 ′ recovered abrasive 6 new cutting liquid 6 ′ recovered cutting liquid 20 first centrifugal separator 23 fine particle mixed liquid 23 a Large-diameter fine-particle mixed liquid 24 High-density electric field generator 25 Second centrifuge 26 Large-diameter fine-particle solid 28 Foreign matter removing device 31 Foreign matter

Claims (5)

[Claims] 1. The used abrasive slurry used for a wire saw is guided to a first centrifugal separator to separate recovered abrasive particles and a fine particle mixed liquid containing fine cutting chips and crushed abrasive particles, Passing the fine liquid mixture through a high-density electric field to increase the particle size of the fine solids in the fine liquid mixture,
And separated into the increased-diameter fine solids and the recovered cutting liquid by mixing the collected abrasive grains separated by the first centrifuge and the recovered cutting liquid separated by the second centrifuge. A method for regenerating a wire saw abrasive slurry, which is reused as an abrasive slurry. 2. The used abrasive slurry used for the wire saw is passed through a high-density electric field to increase the particle size of the solid particles in the abrasive slurry, and then guided to a first centrifugal separator for recovery. Separating the abrasive grains and the increased-fine-particles mixed liquid containing the increased-diameter-fine-particles solids, further guiding the increased-diameter-fine-particles mixed liquid to a second centrifuge to separate them into the increased-size fine-particle solids and the recovered cutting liquid, A method for regenerating a wire saw abrasive slurry, comprising mixing the collected abrasive separated by the first centrifugal separator and the collected cutting liquid separated by the second centrifugal separator, and reusing the collected cutting liquid as an abrasive slurry. 3. A first centrifugal separator for introducing used abrasive slurry from a wire saw to separate recovered abrasive grains and a fine-grained mixed liquid containing fine cutting chips and crushed abrasive grains. A high-density electric field generator for increasing the particle size of fine solids in the fine-particle mixture by applying a high-density electric field to the fine-particle mixture separated by the centrifuge; A second centrifugal separator for separating the increased diameter fine-grained solids and the recovered cutting liquid, a recovered abrasive separated by the first centrifuge, and a recovered separated by the second centrifuge A wire saw abrasive slurry regenerating apparatus, comprising: a slurry supply device that introduces a cutting liquid, introduces new abrasive grains and a new cutting liquid, and supplies an abrasive slurry to a wire saw. 4. A high-density electric field generator for applying a high-density electric field to a used abrasive slurry from a wire saw to increase the particle size of solid particles in the abrasive slurry, A first centrifugal separator for introducing an abrasive slurry containing solid particles having an increased diameter to separate recovered abrasive particles and a mixed liquid of increased diameter fine particles, and separated by the first centrifugal separator; A second centrifugal separator that separates the enlarged fine solid and the recovered cutting liquid from the enlarged fine mixed liquid, and the recovered abrasive separated by the first centrifuge and separated by the second centrifuge And a slurry supply device for introducing the recovered cutting liquid, introducing new abrasive grains and the new cutting liquid, and supplying the abrasive slurry to the wire saw. 5. A foreign matter removing device which removes foreign matter by introducing the collected abrasive particles separated by the first centrifuge and the collected cutting liquid separated by the second centrifuge. The apparatus for regenerating a wire saw abrasive slurry according to claim 3 or 4.