JP5535985B2 - Waste liquid purification equipment - Google Patents

Description

The present invention, machining oils, relates that equipment to purify waste, such as a water soluble coolant.

  Patent Document 1 listed below discloses an apparatus for processing water-based industrial waste liquid by a physical method to generate reusable clear and activated water. Specifically, the apparatus disclosed in Patent Document 1 below circulates aqueous industrial waste liquid stored in a surfactant injection device through a circulation pipe, and includes a turbulent flow forming section and a magnetic processing section in the circulation pipe. By stirring and magnetizing the effluent in the circulation line by turbulent flow, fine bubbles are attached to the fat and sludge particles in the effluent, and the fat and sludge in the aqueous industrial effluent in the surfactant injection device The particles are levitated and separated and recovered.

JP 2006-289317 A

However, when the dirt component is a heavy material such as a metal compound, there is a problem that even if microbubbles adhere to the particles, the buoyancy in the surfactant injection device is not sufficient, and efficient separation and recovery cannot be performed.
In view of such a problem, the present invention allows the dirt component to be efficiently separated even if the waste liquid contains a heavy substance such as a metal compound as the dirt component by precipitating and separating the dirt component by a physical method. The problem is to separate and recover.

The first invention of the present invention is a magnetic powder injection device for injecting magnetic powder as a coagulant into waste liquid, and magnetizing the magnetic powder by applying a rotating magnetic field to the waste liquid mixed with the magnetic powder. A waste liquid purifying apparatus comprising: an aggregating reaction apparatus; and a sedimentation tank in which waste liquid from the aggregating reaction apparatus is injected and magnetic powder is precipitated to allow the purified liquid to be taken out from above.
According to the first invention, since the dirt component in the waste liquid is adhered to the surface of the magnetic powder and is precipitated in the settling tank, the purification function can be achieved even if the dirt component contains a metal compound.
In addition, since the dirt component in the waste liquid is precipitated and separated from the liquid, the dirt component can be removed more easily than when the dirt component is floated. Here, since the flocculant is a magnetic powder, the specific gravity is higher than that of a general flocculant and the dirt component is low in specific gravity, such as ceramics. Precipitation in the tank can be accelerated.

According to a second aspect of the present invention, in the first aspect, the magnetic powder is a ferrite powder.
According to the second invention, since the ferrite powder surface has fine cavities, the surface area as the flocculant can be increased, and the dirt component in the waste liquid can be attached efficiently.

According to a third aspect of the present invention, in the first or second aspect, the agglomeration reaction apparatus includes a coil arranged in a cylindrical shape so as to be supplied with a three-phase alternating current and generate a rotating magnetic field therein. Features.
According to the third invention, since the waste liquid mixed with the ferrite powder is stirred by receiving the rotating magnetic field, the time during which the waste liquid passes through the rotating magnetic field is maintained for a long time. Adhesion can be promoted.

According to a fourth aspect of the present invention, in the third aspect, the agglomeration reaction apparatus includes a spiral pipe that allows waste liquid to pass inside the cylindrically arranged coil.
According to the fourth aspect of the invention, the waste liquid mixed with the ferrite powder is stirred by receiving the rotating magnetic field, and the pipe is spiraled, so that the time during which the waste liquid passes through the rotating magnetic field is maintained long. It is possible to promote the adhesion of dirt components to the ferrite powder surface.

According to a fifth invention of the present invention, in any one of the first to fourth inventions, the agglomeration reaction device includes a frequency conversion device that arbitrarily switches a frequency of an alternating current for generating the rotating magnetic field. To do.
According to the fifth aspect of the invention, the frequency of the alternating current for generating the rotating magnetic field can be switched. For example, the frequency corresponding to the dirt component can be set to efficiently attach the dirt component to the surface of the magnetic powder. Can do.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, a magnet is provided in a lower portion of the precipitation tank.
According to the sixth invention, since the magnet is provided at the lower part of the sedimentation tank, the magnetic powder having the dirt component adhered thereto can be quickly precipitated by gravity and the attraction force by the magnet, and the waste liquid purification efficiency can be improved. it can.

A seventh invention of the present invention includes the centrifuge according to any one of the first to sixth inventions, which receives the magnetic powder precipitated in the settling tank and generates a lump of magnetic powder. Features.
According to the seventh invention, the magnetic powder can be reused by collecting the magnetic powder and subjecting it to a regeneration treatment.

According to an eighth aspect of the present invention, in the seventh aspect, the centrifugal separator is disposed in a rotary drum made of a filter whose rotation center is set in a vertical direction, and is slidably disposed in the rotary drum. A scraper that rotates on the same axis as the drum and scrapes the collected matter adhering to the inner wall of the rotating drum downward, and supplies magnetic powder from the sedimentation tank into the rotating drum, rotates the rotating drum and By rotating the scraper relative to the rotating drum, the liquid is taken out from the outer peripheral side of the rotating drum, and the magnetic powder as the recovered material is taken out from the lower side of the scraper.
According to the eighth aspect of the invention, the scraper scrapes the collected material adhering to the inner wall of the rotating drum downward, so that the collected material can be collected continuously while operating the centrifuge.

According to a ninth aspect of the present invention, in the eighth aspect, the rotating drum and the scraper are rotated relative to the rotating drum by rotating the scraper in the same direction as the rotating drum and at a higher speed than the rotating drum. A rotation mechanism is provided.
According to the ninth aspect of the present invention, since the relative rotation is generated between the rotating drum and the scraper while rotating both, the continuous recovery of the recovered material can be realized while operating the centrifuge.

According to a tenth aspect of the present invention, in the eighth or ninth aspect of the present invention, a predetermined gap is formed between the inner wall of the rotating drum and the outer peripheral end of the scraper, and the magnetic material from the settling tank The powder is supplied to the lower part of the rotating drum, and the remaining liquid that does not flow out to the outer peripheral side of the rotating drum flows out from the upper part of the rotating drum through the gap.
According to the tenth aspect of the present invention, the magnetic powder that could not pass through the filter constituting the rotating drum is laminated in the gap, and the liquid in the magnetic powder is filtered through the laminated body, filtered, and filtered from below to above. The liquid pushed out is taken out from the upper part of the rotating drum. For this reason, a liquid is filtered also by the magnetic substance powder laminated | stacked in addition to the filter of a rotating drum, and the filtration capability as a centrifuge can be improved.

According to an eleventh aspect of the present invention, in any one of the eighth to tenth aspects, the outer periphery of the rotating drum is provided with a cleaning device that ejects a gas having a predetermined pressure toward the outer periphery of the rotating drum at an arbitrary timing. The magnetic substance powder adhering to the inner wall of the rotating drum is removed by the gas.
According to the eleventh invention, the magnetic powder adhered to the inner wall of the rotating drum is removed by the gas ejected from the washer at an arbitrary timing, so that the magnetic powder is prevented from adhering to the inner wall of the rotating drum and solidifying. be able to. Therefore, the performance of the centrifuge can be maintained.

According to a twelfth aspect of the present invention, in any one of the first to eleventh aspects, a surfactant is injected into the waste liquid supplied to the agglomeration reaction apparatus.
According to the twelfth aspect, the surfactant is injected into the waste liquid, so that the waste liquid adheres to the surface of the magnetic powder, and the adhesion of the dirt component to the magnetic powder surface can be promoted.

According to a thirteenth aspect of the present invention, in any one of the first to twelfth aspects, the storage device is provided with a liquid storage tank attached to the functional device that generates waste liquid, the waste liquid from the functional device is stored in the liquid storage tank, and the aggregation reaction is performed. While supplying to an apparatus, the purified liquid taken out from the said precipitation tank is stored in a liquid storage tank, It is characterized by the above-mentioned.
According to the thirteenth aspect, since the waste liquid purification function is provided as a circulation system in the liquid storage tank attached to the functional device, the waste liquid purification function can be simply configured.

14th invention of this invention inject | pours magnetic substance powder as a coagulant | flocculant in the extracted waste liquid, stirs the waste liquid mixed with magnetic substance powder by applying a rotating magnetic field, and puts the waste liquid after stirring into a sedimentation tank. It is a waste liquid purification method characterized by precipitating magnetic substance powder and taking out the purified liquid from the upper part of the precipitation tank.
According to the fourteenth aspect of the present invention, the dirt component in the waste liquid is adhered to the magnetic powder and precipitated in the settling tank, so that the purification function can be achieved even if the dirt component contains a metal compound.
In addition, since the dirt component in the waste liquid is precipitated and separated from the liquid, the dirt component can be removed more easily than when the dirt component is floated.

According to a fifteenth aspect of the present invention, in the fourteenth aspect, the magnetic powder is a ferrite powder.
According to the fifteenth invention, since there are fine cavities on the surface of the ferrite powder, the surface area as the aggregating agent can be increased, and the dirt component in the waste liquid can be attached efficiently.

It is a piping diagram of one embodiment of the waste liquid purification apparatus concerning the present invention. It is a fragmentary sectional top view of the centrifuge in the said embodiment. It is the III-III sectional view taken on the line of FIG.

An embodiment of the present invention will be described with reference to the drawings.
The embodiment of FIG. 1 is a case where the present invention is applied to an apparatus for purifying used processing oil that is used and discharged as a processing oil in a forging device or a rolling device (corresponding to a functional device in the present invention). Indicates.
In the figure, reference numeral 50 denotes an oil storage tank (corresponding to a liquid storage tank in the present invention) which is attached to the functional device (not shown) and stores the used processing oil. The oil storage tank 50 is processed oil from the functional device. The large metal powder mixed in the oil at the time of machining is removed here, and the finer metal powder is then removed from the processed oil by the filter 52, and the waste oil (the waste liquid in the present invention) Stored in the oil storage tank 50.

The waste oil stored here is supplied to the agglomeration reaction apparatus 20 by the pump 61. A magnetic powder injection device 10, a flocculant injection device 71, and a surfactant injection device 72 are connected in the supply path. Ferrite powder (magnetic material in the present invention) is used as a flocculant from the magnetic powder injection device 10. Equivalent to flour) is injected into the waste oil. Here, 12 is a tank that stores ferrite powder, and 11 is a tube pump that sends the ferrite powder in the tank 12 toward piping for supplying waste oil. The ferrite powder used here has a powder size of, for example, about 2 to 6 microns.
The flocculant injection device 71 has the same configuration as that of the magnetic substance powder injection device 10, and a general flocculant is injected into the waste oil. As the flocculant, ash, shirasu from Kagoshima Prefecture, etc. are used.
Further, the surfactant is injected into the waste oil from the surfactant injection device 72. As the surfactant, a silicon-based solution mixed in the paint is generally used.

Although not shown in detail in FIG. 1, the agglomeration reaction apparatus 20 is provided with a coil arranged in a cylindrical shape so as to be supplied with a three-phase alternating current and generate a rotating magnetic field therein, and arranged in this cylindrical shape. A spiral pipe that allows waste oil to pass therethrough is provided inside the coil cylinder.
In the agglomeration reaction apparatus 20, the waste oil mixed with the ferrite powder is magnetized and stirred by receiving a rotating magnetic field, and the dirt component in the waste liquid adheres to the ferrite powder surface. Since the pipe through which the waste oil passes is formed in a spiral shape, the time during which the waste oil passes through the rotating magnetic field is maintained for a long time, and adhesion of dirt components to the ferrite powder surface can be promoted. Further, as described above, since the general flocculant and surfactant are injected into the waste oil, the general flocculant action on the waste oil is performed, and the surfactant adheres well to the ferrite powder surface by the surfactant. Thus, it is possible to promote the adhesion of dirt components to the ferrite powder surface.
The pipe through which the waste oil passes inside the coil cylinder may not be spiral as described above, but may be a straight pipe having a thickness corresponding to the outer edge diameter of the spiral pipe. In this case, a plurality of small vortex flows are generated in the waste oil by the rotating magnetic field in the pipe, and a large vortex flow is further induced by the vortex flow. Such complicated eddy currents can promote the adhesion of dirt components to the ferrite powder surface.

Although not shown, the agglutination reaction apparatus 20 includes a frequency converter that arbitrarily switches the frequency of an alternating current for generating a rotating magnetic field. The frequency converter is adjusted to 10 to 500 Hertz according to the type of metal compound that is a dirt component in the waste oil to be purified.
Thus, by switching the frequency of the alternating current for generating the rotating magnetic field, it is possible to set the frequency according to the dirt component and efficiently attach the dirt component to the surface of the ferrite powder.

Waste oil that has passed through the agglomeration reactor 20 is sent to a settling tank 30 where ferrite powder and general flocculant in the waste oil are precipitated. A waste oil inflow path 31 is formed inside the precipitation tank 30, and the waste oil inflow path 31 extends from the upper edge of the precipitation tank 30 to the vicinity of the bottom of the precipitation tank 30. Waste oil from the agglomeration reactor 20 is received at the upper part of the waste oil inflow path 31 and flows into the sedimentation tank 30 from the lower part.
The sedimentation tank 30 is provided with an overflow portion 33 on the upper outer peripheral side, and is piped so that the overflowed oil is returned to the oil storage tank 50 through the filter 52.
An electromagnet (corresponding to a magnet in the present invention) 32 is provided below the waste oil inflow passage 31. As described above, since the magnet is provided in the lower portion of the waste oil inflow path 31, the ferrite powder having the dirt component attached thereto can be quickly precipitated by gravity and the attraction force by the magnet, and the purification efficiency of the waste oil can be increased.
Further, a pipe is connected to a portion of the precipitation tank 30 where the ferrite powder is precipitated, and the precipitate is supplied to the centrifuge 40 via a valve 67 and a slurry pump 68.

The centrifuge 40 is piped so that the rotating drum 41 is rotated by a motor 42 to separate oil contained in the precipitate and return the oil to the oil storage tank 50. Further, an extruder 81 is integrally provided at the lower part of the rotating drum 41, and the extruder 81 extrudes the ferrite powder remaining in the rotating drum 41 from the rotating drum 41 to form a cake of ferrite powder. Has been. A cake tank 82 is provided below the extruder 81 so that cakes extruded from the extruder 81 are stored.
The cake can be reused by heating to remove the oil. Or the ferrite powder containing oil can also be put into an incinerator as it is and can be used as a heating accelerator of an incinerator.

  The ferrite powder precipitated in the lower part of the settling tank 30 is branched from the route sent to the centrifuge 40 and sent to the demagnetizer 66 via the valve 69 and the slurry pump 63, where the ferrite powder is demagnetized. After being broken, it is supplied again to the agglomeration reaction apparatus 20. By configuring the circulation path in this way, the ferrite powder can be used repeatedly.

表１において、「診断結果」の「○」は良好、「△」は経過観察要、「×」は要注意を意味する。
また、この切削油の濾過後の残渣量の比較は表２のとおりとなっている。なお、残渣量の求め方は、試料を１００ｍＬ分取し、ヘキサン・アセトン混合溶媒に溶かし、孔径０．２μｍのメンブランフィルタで濾過し、濾過前後の重量差から濾過残渣量を求めた。

The analysis result of the cutting oil purified by the purification apparatus of the above-described embodiment is as shown in Table 1 below, and the diagnosis result can be reused as an additional oil.

In Table 1, “◯” in “diagnosis result” means good, “Δ” means follow-up, and “x” means attention.
Moreover, the comparison of the amount of residues after filtration of this cutting oil is as shown in Table 2. The amount of residue was obtained by taking 100 mL of a sample, dissolving it in a hexane / acetone mixed solvent, filtering through a membrane filter having a pore size of 0.2 μm, and obtaining the amount of filtration residue from the weight difference before and after filtration.

As described above, according to the waste oil purification apparatus of the embodiment, the dirt component in the waste oil is adhered to the ferrite powder and is precipitated in the settling tank 30, so that the purification function can be achieved even if the dirt component contains a metal compound. Can be accomplished. In addition, since the dirt component in the waste oil is precipitated and separated from the oil, the removal operation of the dirt component can be facilitated as compared with the one in which the dirt component is floated. Here, since the flocculant is a ferrite powder, the ferrite powder settling tank 30 has a specific gravity higher than that of a general flocculant and a dirt component having a low specific gravity, such as ceramics, to which the dirt component is adhered. Can speed up the precipitation.
In addition, since the oil storage tank 50 attached to the functional device is provided with the waste oil purification function as a circulation system, the waste oil purification function can be simply configured.

  In the embodiment of FIG. 1, the processing oil discharged from the functional device, purified as described above by the purification device including the agglomeration reaction device 20 and the sedimentation tank 30, circulated and stored in the oil storage tank 50 is supplied to the pump 65. Is again supplied to the functional device and used.

Next, the detailed structure of the centrifuge 40 will be described with reference to FIGS.
The centrifugal separator 40 has a rotary drum 41 made of a sintered filter whose center of rotation is set in the vertical direction, and is slidably disposed in the rotary drum 41, and rotates relative to the rotary drum 41 on the same axis. A scraper 43 that scrapes downward the collected material adhering to the inner wall of the drum 41 is provided.
Specifically, the upper and lower ends of the rotating drum 41 are sandwiched between the ring bodies 412, and the upper ring body 412 is fixed to the lower end of the outer cylinder 411 that is rotatably supported in the support body 401. . The lower ring body 412 is fixed to the upper end of the guide 413. The guide 413 is formed in a substantially funnel shape, and a solid material (ferrite powder) scraped off by the scraper 43 is provided below the guide body. Guide toward the base 49. Although not shown, the above-described extruder 81 is provided at the lower part of the base 49.
On the other hand, the scraper 43 is arranged so that the main body 432 has the same rotation center as that of the rotating drum 41, and fins 434 are provided spirally on the outer periphery of the main body 432, and the tips of the fins 434 are arranged at the tips of the rotating drum 41. A predetermined gap is formed with respect to the inner periphery. This gap is set to 3 mm, for example. The hole diameter of the filter of the rotary drum 41 is 2 microns.
The upper part of the main body 434 is fixed to the lower end of the inner cylinder 431 that is rotatable in the outer cylinder 411, and the lower part of the main body 434 is fixed to the upper end of the lower body 433 disposed in the guide 413. ing.
A motor 42 is fixed to the side of the support body 401 via a coupling body 402. A pulley 441 having a double groove is fixed to an output shaft of the motor 42, and two pulleys that are belt-coupled to the pulley 441, respectively. 442 and 443 are fixed to the upper ends of the inner cylinder 431 and the outer cylinder 411 so as to rotate. The pulley 442 has a smaller diameter than the pulley 443, so that the inner cylinder 431 is rotated at a higher speed than the outer cylinder 411. Here, the two pulleys 442 and 443 constitute the rotation mechanism 44 of the present invention.
The inner cylinder 431 and the main body 432 are formed with a through hole at the center of rotation thereof, and a head 46 is connected to the upper end of the inner cylinder 431, and the head 46 is set in the through hole of the inner cylinder 431. A slurry of ferrite powder is supplied from the tank 30. On the other hand, a radial hole connected to the through hole is formed at the lower end of the main body 432, and ferrite powder slurry supplied through the through hole of the inner cylinder 431 is introduced into the rotary drum 41. I am doing so.
Therefore, the ferrite powder slurry from the settling tank 30 is supplied into the rotating drum 41, and the rotating drum 41 is rotated and the scraper 43 is rotated relative to the rotating drum 41, whereby the rotating drum 41, which is a sintered filter. The oil in the slurry of the ferrite powder is taken out from the outer periphery side of the steel, and the ferrite powder as the recovered material is taken out from below the scraper 43.

Thus, the centrifuge 40 is configured, and the scraper 43 scrapes the collected material adhering to the inner wall of the rotating drum 41 downward, so that the collected material can be collected continuously while the centrifuge 40 is operated.
In addition, since the relative rotation is generated between the rotating drum 41 and the scraper 43 while rotating the rotating drum 41 and the scraper 43, it is possible to realize continuous recovery of the recovered material while operating the centrifugal separator 40.

As described above, a predetermined gap is formed between the inner wall of the rotating drum 41 and the outer peripheral end of the scraper 43, and ferrite powder slurry is supplied to the lower portion of the rotating drum 41. If there is oil that does not flow out on the inner peripheral side of the rotating drum 41, the oil flows out from the upper portion of the rotating drum 41 through the gap. In other words, a passage is formed between the inner peripheral end of the ring body 412 on the upper side of the rotating drum 41 and the outer peripheral end of the main body 432 of the scraper 43, and communicated with this passage to the lower portion of the outer cylinder 411. Are formed with radial holes.
Ferrite powder that could not pass through the filter forming the rotary drum 41 is laminated in the gap, and the oil in the ferrite powder is filtered through the laminate, and the oil that has been filtered and extruded upward is the rotary drum. 41 is taken out from the top. For this reason, oil is filtered also by the ferrite powder laminated | stacked in addition to the filter of the rotating drum 41, and the filtration capability as the centrifuge 40 can be improved.
The upper portion of the centrifuge 40 is covered with a case upper portion 47 that covers the entire centrifuge 40 except for the head 46, and the lower portion of the centrifuge 40 is covered with a case lower portion 48 that is partially coupled to the case upper portion 47. It has been broken.
As described above, the oil that has passed through the filter of the rotating drum 41 to the outer peripheral side and the oil that flows out from the lower portion of the outer cylinder 411 are captured inside the case lower portion 48 and sent to the oil storage tank 50.

The case lower part 48 on the outer periphery of the rotating drum 41 is provided with a cleaning device 45 that ejects air (gas) at a predetermined pressure toward the outer periphery of the rotating drum 41 at an arbitrary timing. The ferrite powder adhering to the inner wall of the rotary drum 41 is removed by the jetted air.
Thus, since the ferrite powder adhering to the inner wall of the rotating drum 41 is removed by the air ejected from the cleaning device 45 at an arbitrary timing, it is possible to prevent the ferrite powder from adhering to the inner wall of the rotating drum 41 and solidifying. it can. Therefore, the performance of the centrifuge 40 can be maintained.

  The present invention is not limited to the appearance and configuration described in the above embodiment, and various modifications, additions, and deletions can be made without changing the gist of the present invention. For example, waste water may be waste water in addition to waste oil. The magnetic powder as the flocculant may be other than ferrite powder as long as it is a magnetic powder.

DESCRIPTION OF SYMBOLS 10 Magnetic substance powder injection apparatus 20 Aggregation reaction apparatus 30 Precipitation tank 32 Electromagnet (magnet)
40 Centrifugal separator 41 Rotating drum 42 Motor 43 Scraper 44 Rotating mechanism 45 Washer 46 Head 81 Extruder 50 Oil storage tank 66 Demagnetizer 71 Coagulant injection device 72 Surfactant injection device

Claims (4)

A flocculant injection device for injecting magnetic powder as a flocculant into the waste liquid;
An agglomeration reaction apparatus that magnetizes and stirs the magnetic powder by applying a rotating magnetic field to the waste liquid mixed with the magnetic powder;
A settling tank in which waste liquid from the agglomeration reaction apparatus is injected, and magnetic substance powder is precipitated and the purified liquid can be taken out from the upper part ;
A centrifuge for receiving the magnetic powder precipitated in the settling tank and generating a lump of magnetic powder ;
The centrifugal separator is disposed in a rotary drum made of a filter whose rotation center is set in the vertical direction, and is slidably disposed in the rotary drum, and is relatively rotated coaxially with the rotary drum and attached to the inner wall of the rotary drum. A scraper that scrapes the collected material downward,
By supplying magnetic powder from the sedimentation tank into the rotating drum, rotating the rotating drum and rotating the scraper relative to the rotating drum, the liquid is taken out from the outer peripheral side of the rotating drum, and below the scraper. A waste liquid purifier for extracting magnetic powder as a recovered material from a waste material. 2. The rotating drum and the scraper according to claim 1 , further comprising a rotating mechanism that rotates relative to the rotating drum when the scraper rotates in the same direction as the rotating drum and at a higher speed than the rotating drum. Waste liquid purification device. In Claim 1 or 2 , it sets so that a predetermined gap may be formed between the inner wall of the rotating drum and the outer peripheral end of the scraper,
The magnetic powder from the settling tank is supplied to the lower part of the rotating drum, and the remaining liquid without flowing out to the outer peripheral side of the rotating drum flows out from the upper part of the rotating drum through the gap. Purification equipment. In any one of claims 1 to 3, wherein comprising a scrubber for jetting a gas at a predetermined pressure toward the rotary drum periphery at an arbitrary timing on the outer circumference of the rotary drum, on the inner wall of the rotary drum by the jetted gas A waste liquid purifier for removing attached magnetic powder.

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