KR20230120741A - Disposal system for waste plastic and disposal method thereof - Google Patents

Abstract

The present invention relates to a waste plastic treatment system and a treatment method thereof. Specifically, the present invention relates to a waste plastic treatment system and method for controlling the size of recycled plastic particles by controlling the size of droplets using a spraying method when depositing recycled plastic particles.

Description

Waste plastic processing system and its processing method {DISPOSAL SYSTEM FOR WASTE PLASTIC AND DISPOSAL METHOD THEREOF}

The present invention relates to a waste plastic treatment system and a treatment method thereof.

In general, when recycled plastic waste is received at a collection point for recycling, these recycled plastic wastes have greatly different characteristics such as flame retardancy and non-flammability, and various materials are mixed in each of flame retardancy and non-flammability. In terms of color, white, Recycled plastic waste in different colors, such as black and red, is received in a mixed state.

In the plastic recycling process, as shown in FIG. 1, impurities were removed through the steps of crushing, dissolving, precipitating, and drying the plastic.

In the conventional precipitation step, in order to measure the size of the precipitated plastic particles, the precipitated plastic particles were collected and measured. Therefore, since the size of the precipitated plastic particles is not constant, it is difficult to handle the plastic particles in a post-precipitation process.

Korean Patent Publication No. 10-2011-0021781

The present invention is intended to provide a waste plastic treatment system and a treatment method therefor.

An exemplary embodiment of the present specification provides a waste plastic treatment system including a precipitation reactor for storing non-solvent and precipitating recycled plastic particles, and a solution supply unit having a spray nozzle for spraying a solution in which waste plastic is dissolved into the precipitation reactor. do.

In one embodiment of the present specification, the solution supply unit may include a tank for storing the solution and a flow path connecting the tank and the spray nozzle, and the spray nozzle may be provided at an end of the flow path.

In one embodiment of the present specification, a flow controller for adjusting the injection amount of the solution using a valve may be further included.

In one embodiment of the present specification, the flow path may be introduced into an upper surface of the precipitation reactor, and the spray nozzle may spray the solution toward the surface of the non-solvent.

In another embodiment of the present specification, the flow path is drawn into the side of the precipitation reactor, one or more distribution ports are provided on the side of the flow path, the injection nozzles are coupled to the one or more distribution ports, respectively, and the non-solvent The solution may be sprayed toward the surface of the water. Specifically, nozzles are provided according to the number of the distribution ports, and one or more nozzles may be coupled to correspond to one or more distribution ports.

In another embodiment of the present specification, the flow path is a main pipe drawn into the side of the precipitation reactor; and one or more distribution pipes provided on a side surface of the main pipe, wherein the spray nozzles are coupled to ends of the one or more distribution pipes, respectively, and may spray the solution toward the surface of the non-solvent.

In one embodiment of the present specification, the precipitation reactor may further include a main body for storing the non-solvent and the precipitated recycled plastic particles, and an agitator positioned in the main body to mix the non-solvent and the solution by rotation. can

In one embodiment of the present specification, a measurement unit for measuring the size of the recycled plastic particles may be further included. The measuring unit includes an irradiation unit for irradiating laser or light onto the recycled plastic particles, a scattered light detector for detecting scattered light scattered while the laser or light passes through the recycled plastic particles, and a scattered light detector that detects scattered light based on a change in intensity or angle of the scattered light. A particle size calculation unit for calculating the size of the plastic particles may be included.

Another embodiment of the present specification provides a method for treating waste plastic, which includes precipitating recycled plastic particles by spraying a solution in which the waste plastic is dissolved into a precipitation reactor in which a non-solvent is stored.

According to the waste plastic treatment system and the treatment method according to the exemplary embodiments of the present invention, the plastic particle size can be controlled through the injection method.

According to the waste plastic treatment system and method according to other embodiments of the present invention, the process of recycling waste plastic can be improved by simplifying the process after precipitation by adjusting the plastic particle size to a certain level.

1 is a diagram showing a conventional wastewater treatment process.
2(a) shows a waste plastic treatment system equipped with a dropper without an injection nozzle, and FIG. 2(b) shows a waste plastic treatment system equipped with an injection nozzle.
3 is a schematic diagram showing a waste plastic treatment system according to a first embodiment of the present invention.
4 is a schematic diagram showing a waste plastic treatment system according to a second embodiment of the present invention.
5 is a schematic diagram showing a waste plastic treatment system according to a third embodiment of the present invention.
6 is a schematic diagram showing a waste plastic treatment system according to a fourth embodiment of the present invention.
7 is a schematic diagram showing a solution supply unit according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. However, the drawings are for illustrating the present invention, and the scope of the present invention is not limited by the drawings.

2(a) shows a waste plastic treatment system equipped with a dropper without an injection nozzle, and FIG. 2(b) shows a waste plastic treatment system equipped with an injection nozzle.

As shown in FIG. 2 (a), a dropper without an injection nozzle has limitations in adjusting the size of a dropped droplet. When the size of the droplets is large, additives such as plasticizers are trapped in the waste plastic chain, creating an environment in which it is difficult to escape during solvent extraction, thereby impairing plasticizer removal efficiency. On the other hand, when the spray type spray nozzle is applied as shown in FIG. 2 (b), the droplets are sprayed finely, and the sprayed microdroplets have a large surface area in the non-solvent, so that additives such as plasticizers can be efficiently discharged to the outside of the waste plastic. create an environment in which

An exemplary embodiment of the present specification provides a waste plastic treatment system including a precipitation reactor for storing non-solvent and precipitating recycled plastic particles, and a solution supply unit having a spray nozzle for spraying a solution in which waste plastic is dissolved into the precipitation reactor. do.

3 is a schematic diagram showing a waste plastic treatment system according to a first embodiment of the present invention.

The waste plastic treatment system 100 may include a precipitation reactor 10 and a solution supply unit 20 .

In the precipitation reactor 10, non-solvent 14 is stored, recycled plastic particles can be precipitated through the non-solvent 14, and the solution supply unit 20 supplies a solution in which waste plastic is dissolved to the precipitation reactor. (10) can be supplied.

The precipitation reactor 10 may precipitate recycled plastic from which additives dissolved in the solution are removed by mixing the stored non-solvent 14 and the solution supplied from the solution supply unit 20 .

The solution may mean that the polymer contained in the waste plastic is dissolved by mixing the waste plastic with a positive solvent having high solubility for the polymer contained in the waste plastic. When the polymer contained in waste plastic is dissolved in the solvent, physical bonds such as dipole moment between chains and hydrophobic bonds are weakened, and the degree of freedom is increased by loosening the chains, and additives such as plasticizers trapped in the chains are released.

In the precipitation reactor 10, a non-solvent 14 having low solubility for the polymer contained in the waste plastic is stored, and when a droplet of the solution falls into the non-solvent 14, the polymer in the droplet of the solution does not dissolve in the non-solvent. It is precipitated as fine recycled plastic particles 15. Conversely, since the non-solvent 14 has high solubility in additives such as plasticizers, additives such as plasticizers contained in liquid droplets of the solution are dissolved in the non-solvent 14 to increase the purity of precipitated microparticles. That is, the recycled plastic particles 15 precipitated in the precipitation reactor 10 may mean polymer particles included in waste plastic.

The non-solvent 14 refers to a compound having a Hansen Solubility Parameter (HSP) of 10 or more of the polymer contained in the waste plastic.

Therefore, the precipitation reactor 10 may increase the ratio of the non-solvent 14 to the solution by contacting and mixing the solution and the non-solvent 14 and decrease the solubility of the polymer in the solvent to precipitate a polymer having low solubility.

The precipitation reactor 10 includes a main body 11 that stores non-solvent and precipitated recycled plastic particles 15 and an agitator 12 that is located in the main body 11 and mixes the non-solvent 14 and the solution by rotation. can include

In the precipitation reactor 10, the solution falls into the non-solvent 14 and the solution and the non-solvent 14 are mixed, and the recycled plastic particles 15 or polymer particles may be precipitated, but the polymer dissolved in the solution may remain. there is. Therefore, the stirrer 12 may increase the efficiency of precipitation of the polymer dissolved in the solution by stirring the non-solvent 14 supplied with the solution to increase the contact rate between the non-solvent 14 and the solution.

The precipitation reactor 10 may further include a non-solvent inlet 13 for injecting the non-solvent 14 into the main body 11 . As the solution is supplied to the precipitation reactor 10, the concentration of the non-solvent 14 stored in the main body 11 may decrease. Accordingly, the non-solvent inlet 13 may inject the non-solvent 14 into the main body 11 to maintain the concentration of the non-solvent stored in the precipitation reactor 10 .

The waste plastic may be waste polyvinyl chloride. The non-solvent 14 refers to a compound having a Hansen Solubility Parameter (HSP) of polyvinyl chloride of 10 or more.

Specifically, the non-solvent 14 refers to a compound having a Hansen Solubility Parameter (HSP) of polyvinyl chloride of 10 or more and 20 or less.

At this time, the Hansen solubility factor of polyvinyl chloride means the difference between the Hansen parameter between the two substances, the solute and the solvent. The Hansen solubility factor is a value proportional to the solubility of two substances, through which the solubility of two substances can be calculated. As the two materials have similar properties to each other, the Hansen parameter values are similar, so the HSP value is low, and it can be predicted that the two materials will dissolve well through the HSP value.

The Hansen solubility factor can be calculated by the following formula, and when using the HSPip software that easily calculates it, δd, δp, and δh of the two materials can be obtained, and the HSP value with the corresponding solvent can be calculated by applying the corresponding value to the following formula .

In one embodiment of the present invention, the non-solvent is a hydrocarbon compound containing at least one selected from the group consisting of alcohol, ether, cycloalkane, ester, carboxylic acid, and nitrile.

In one embodiment of the present invention, the non-solvent is ethanol, isopropyl alcohol, ethyl acetate or acetonitrile.

In one embodiment of the present invention, the non-solvent is preferably isopropyl alcohol.

In one embodiment of the present invention, the good solvent of the polyvinyl chloride is a ketone-based solvent; Cycloether-based solvents; linear or cyclic carbonate-based solvents; or a hydrocarbon-based solvent having 1 to 10 carbon atoms.

The ketone-based solvent may be, for example, methyl ethyl ketone.

The cycloether-based solvent may be, for example, tetrahydrofuran.

In one embodiment of the present invention, the linear carbonate-based solvent is dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), ethyl propyl carbonate (EPC), ethyl methyl carbonate (EMC) or methyl It may be propyl carbonate (MPC), but is not limited thereto.

In one embodiment of the present invention, the cyclic carbonate-based solvent is ethylene carbonate (EC), propylene carbonate (PC), 1,2-butylene carbonate (BC), 2,3-butylene carbonate, 1,2- It may be pentylene carbonate, 2,3-pentylene carbonate, vinylene carbonate (VC), vinyl ethylene carbonate or fluoroethylene carbonate, but is not limited thereto. Preferably, the cyclic carbonate-based solvent may be propylene carbonate.

In one embodiment of the present invention, the hydrocarbon-based solvent having 1 to 10 carbon atoms may be methylene chloride or ethylene chloride, but is not limited thereto.

In one embodiment of the present invention, the good solvent for polyvinyl chloride is preferably methyl ethyl ketone.

The solution supply unit 20 may include a spray nozzle 23 . The injection nozzle 23 injects a solution in which waste plastic is dissolved into the precipitation reactor 10 .

As shown in FIG. 2(a), the size of the droplet that is dropped in the dropper without the injection nozzle is 1 mm to 5 mm, and there is a limit to adjusting the size of the droplet.

On the other hand, when the injection nozzle 23 is introduced as shown in FIG. 3, the size of the droplets can be adjusted from 1 μm to hundreds of microns, and specifically, from 1 μm to 800 μm.

As the size of the droplet decreases, the surface area in which the droplet contacts the non-solvent increases, and the probability that the polymer in the solution contacts the non-solvent increases. By adjusting the size of the droplets, it is possible to control the size of the final product, the recycled plastic particles 15, and the probability that additives such as plasticizers in the droplets move to the non-solvent and be removed from the polymer increases, thereby increasing the purity of the precipitated particles.

The injection nozzle 23, that is, the sprayer, may be a tow fluid nozzle or a rotary wheel type nozzle.

The solution supply unit 20 may further include a tank 21 and a flow path 22 . The tank 21 may store a solution, and the flow path 22 may supply the solution stored in the tank 21 to the precipitation reactor 10 . At this time, the spray nozzle 23 is provided at an end of the flow path 22 .

The tank 21 may further include a heating unit (not shown) to adjust the solubility of the waste plastic in the solvent. The temperature of the heating unit may be controlled by the measuring unit 30 and the controller 40 to be described later.

The channel 22 may have a hollow structure, and may have a cylindrical shape, a square column shape, a polygonal column shape, a shape in which the diameter decreases toward the precipitation reactor 10, etc. ), it is not particularly limited as long as it can be supplied.

It may further include a flow controller (not shown) for adjusting the injection amount of the solution using a valve. Specifically, the flow controller may be provided inside the flow path 22 to control the supply amount of the solution or the size of the droplet of the solution. For example, when the flow path 22 is provided in the form of a cylinder with a hollow inside, the flow controller may be provided in a form capable of adjusting the inner diameter of the flow path.

The solution supply unit 20 may include a flow meter (not shown), and for example, the flow meter may be a flow control type flow meter.

At this time, the solution supply unit 20 may spray and supply the solution to the precipitation reactor 10 by adjusting the flow rate of the solution without additional configuration. In addition, the solution supply unit 20 may measure the supply amount of the solution supplied to the precipitation reactor 10 by means of a flow meter, and may measure the non-solvent concentration based on the measured supply amount of the solution.

Therefore, the waste plastic treatment system 100 according to the present invention may further include a non-solvent concentration calculation unit (not shown) for calculating the non-solvent concentration of the precipitation reactor 10 based on the supply amount of the solution measured by the flow meter. can

4 is a schematic diagram showing a waste plastic treatment system according to a second embodiment of the present invention.

The waste plastic treatment system 100 may further include a measurement unit 30 and a control unit 40 together with the precipitation reactor 10 and the solution supply unit 20 .

The measurement unit 30 may measure the size of recycled plastic particles. In other words, the measurement unit 30 may measure the size of polymer particles precipitated in the non-solvent of the precipitation reactor 10 . Here, the particle size may mean the particle diameter of the recycled plastic particles 15 or polymer particles.

The measurement unit 30 may include any one of a laser measurement device and an optical measurement device, and the measurement unit 30 may include an irradiation unit 31 , a scattered light detector 32 and a calculation unit 33 .

The irradiation unit 31 may irradiate the plastic particles with laser or light, and the scattered light detector 32 may detect scattered light generated when the laser or light irradiated by the irradiation unit 31 passes through the plastic particles.

The irradiation unit 31 and the scattered light detector 32 may be located on a part of the inner wall of the main body 11, and the irradiation unit 31 and the scattered light detector 32 may be located adjacent to each other or provided at positions facing each other.

The calculation unit 33 may calculate the size of the plastic particles based on the intensity or angle change of the scattered light. At this time, the scattered light passes through the non-solvent, and the calculator 33 may calculate the size of the recycled plastic particles 15 by applying a rate of change according to the passage of the scattered light through the non-solvent.

The controller 40 may control one or more of the precipitation reactor 10 and the solution supply unit 20 based on the size of the plastic particles measured by the measuring unit 30 .

At this time, the control unit 40 may control the rotation of the agitator 12 of the precipitation reactor 10, and may control the temperature of the tank 21 by controlling the heating unit of the solution supply unit 20.

In addition, the control unit 40 may pre-input and store the reference value of the plastic particle size. When the user inputs and stores the plastic particle size to be precipitated as a reference value, the control unit 40 may determine whether to control each component based on the stored reference value.

More specifically, the control unit 40 compares the pre-stored reference value with the size of the precipitated plastic particles received from the calculation unit 33 of the measurement unit 30 to determine the speed of the stirrer 12 of the precipitation reactor 10. Alternatively, the temperature of the heating unit of the solution supply unit 20 may be adjusted.

In one embodiment, when the controller 40 determines that the plastic particle size measured by the measurement unit 30, that is, the polymer particle size exceeds a reference value, the controller 40 controls the agitator 12 of the precipitation reactor 10. ) can accelerate precipitation by increasing the rate, thereby reducing the polymer particle size.

Alternatively, the control unit 40 may increase the solubility of the solution by increasing the temperature of the tank or decrease the size of droplets of the solution supplied to the precipitation reactor 10 by reducing the inner diameter of the flow path 22 of the solution supply unit 20. can

The waste plastic treatment system 100 according to the present invention may further include an aqueous solution supply unit 50 . The aqueous solution supply unit 50 supplies an aqueous solution to the precipitation reactor 10, and the aqueous solution may include an aqueous electrolyte solution.

That is, the non-solvent stored in the precipitation reactor 10 according to the present invention may further include an aqueous electrolyte solution. The plastic particles may be precipitated by phase separation between the non-solvent and the solution, and may be electrochemically precipitated by the aqueous electrolyte solution. Therefore, the aqueous electrolyte solution can accelerate the precipitation of plastic particles.

In addition, the waste plastic treatment system 100 according to the present invention may further include a concentration measuring unit 51 for measuring the concentration of the aqueous solution included in the non-solvent. The concentration measurement unit 51 may derive the concentration of the aqueous electrolyte solution by measuring the electrical conductivity of the non-solvent.

The concentration measurement unit 51 measures the conductivity of the non-solvent before the solution is supplied to the precipitation reactor 10, and the control unit 40 stores the initial conductivity of the non-solvent measured by the concentration measurement unit 51 as a reference value , It can be compared with the conductivity of the non-solvent measured by the concentration measuring unit 51 later.

For example, when the conductivity of the non-solvent measured by the concentration measurement unit 51 is less than the reference value, the control unit 40 may increase the supply amount of the aqueous electrolyte solution of the aqueous solution supply unit 50 .

That is, the waste plastic treatment system 100 according to the present invention can maintain the conductivity of the non-solvent included in the precipitation reactor 10 as the initial conductivity of the non-solvent before the solution is supplied.

In this specification, the embodiment can be divided according to the location and shape of the passage and the spray nozzle, specifically the first embodiment shown in FIG. 3, the third embodiment shown in FIG. 5, and the embodiment shown in FIG. It can be classified as the fourth embodiment.

In the first embodiment of the present specification, the flow path 22 is drawn into the upper surface of the precipitation reactor 10, and the spray nozzle 23 is to spray the solution toward the surface 14 'of the non-solvent. can

In the third embodiment of the present specification, the flow path 22 is introduced into the side of the precipitation reactor 10, one or more distribution ports 24 are provided on the side of the flow path 22, and the injection nozzle ( 23) is coupled to the one or more distribution ports 24, respectively, and can spray the solution toward the non-solvent surface 14'.

In the fourth exemplary embodiment of the present specification, the flow path 22 includes a main pipe 25 drawn into a side surface of the precipitation reactor 10; And one or more distribution pipes 26 provided on the side of the main pipe 25, wherein the spray nozzles 23 are coupled to the ends of the one or more distribution pipes 26, respectively, and the surface of the non-solvent 14 ') to spray the solution.

In the fourth embodiment of the present specification, when the distribution pipe 26 is provided in a plurality of two or more on the side of the main pipe 25, the injection nozzle 23 corresponds to the number of the distribution pipe 26 It can be coupled to the end of two or more distribution pipes 26, respectively, according to the number. For example, as shown in FIG. 7, when three distribution pipes 26 are provided on the side of the main pipe 25, three injection pipes are provided according to the number corresponding to the number of distribution pipes 26. Nozzles 23, 23', 23" may be coupled to the ends of the three distribution pipes 26, 26', 26", respectively.

The waste plastic treatment system may further include a settling unit using a centrifugal separation method to obtain the precipitated recycled plastic particles.

The waste plastic treatment system may further include a filter for filtering the precipitated recycled plastic particles.

The filtering unit includes a filter, and the filter may be 80 mesh (177 μm), but is not limited thereto. The filter may have a size of, for example, 18 mesh to 200 mesh.

The waste plastic treatment system may further include a filtration unit for filtering the precipitated recycled plastic particles and a settling unit using a centrifugal separation method to obtain recycled plastic particles having small particles passing through the filtration unit.

Another embodiment of the present specification provides a method for treating waste plastic, which includes precipitating recycled plastic particles by spraying a solution in which the waste plastic is dissolved into a precipitation reactor in which a non-solvent is stored.

The waste plastic treatment method according to another exemplary embodiment of the present specification may further include obtaining the precipitated recycled plastic particles.

Obtaining the precipitated recycled plastic particles may include precipitating the precipitated recycled plastic particles using a centrifugal separation method.

Obtaining the precipitated recycled plastic particles may include a filtering step of filtering the precipitated recycled plastic particles.

The step of obtaining the precipitated recycled plastic particles may include a filtration step of filtering the precipitated recycled plastic particles; A step of precipitating small recycled plastic particles not obtained in the filtration step using a centrifugal separation method may be included.

The waste plastic treatment method according to another exemplary embodiment of the present specification may further include drying the obtained recycled plastic particles.

Obtaining the precipitated recycled plastic particles may further include a cleaning step of the recycled plastic particles. In the washing step, the filtered recycled plastic particles may be washed with a non-solvent one or more times. Specifically, a series of processes of dispersing the obtained recycled plastic particles in a non-solvent, stirring for a certain time, and filtering may be repeated one or more times and washed. At this time, the description of the non-solvent may refer to the above description.

Obtaining the precipitated recycled plastic particles may further include dehydrating the recycled plastic particles.

For example, in the dehydration step and the drying step, methods such as vacuum filtering, decanter, centrifugation using a centrifuge, and vacuum drying including de-volatilizing may be applied, but are not limited thereto. no.

The drying step may be carried out overnight at a temperature of 75 ° C to 85 ° C.

The overnight may mean 12 to 16 hours.

In another embodiment of the present specification, when a measuring unit and a control unit are applied, setting a reference value and a set value to the control unit (S100), depositing plastic particles (S200), and measuring the size of plastic particles (S300). ) and comparing the plastic particle size with the reference value (S400).

The step of setting the reference value and set value in the control unit (S100) is a step of setting the reference value of the plastic particle size and the operating set value of the precipitation reactor in the control unit. The operation set value of the precipitation reactor may include a rotation speed of an agitator of the precipitation reactor, a solution supply rate, a solution supply amount, and the like.

In the step of depositing the plastic particles ( S200 ), the recycled plastic particles may be deposited by spraying a solution in which the waste plastic is dissolved into the precipitation reactor in which the non-solvent is stored. At this time, the solution may be supplied by spraying through a spray nozzle.

The step of measuring the plastic particle size (S300) is a step of measuring the size of the plastic particles precipitated by mixing the non-solvent and the solution, that is, the polymer particle size. The plastic particles may be immersed in the non-solvent, and the size of the plastic particles immersed in the non-solvent may be measured using a laser or light.

The step of comparing the plastic particle size and the reference value (S400) is the plastic particle size measured in the step of measuring the plastic particle size reference value and the plastic particle size set and stored in the step (S100) of setting the reference value and the set value in the control unit (S300). This is a size comparison step.

When the plastic particle size measured in the step of measuring the plastic particle size (S300) exceeds the set and stored plastic particle size reference value in the step of setting the reference value and set value in the control unit (S100), the rotation speed of the stirrer of the precipitation reactor, the solution The temperature of the solution may be increased, or the supply amount of the solution and the droplet size of the supplied solution may be reduced.

If the measured plastic particle size is less than the reference value, the rotation speed of the stirrer of the precipitation reactor, the temperature of the solution, etc. may be reduced, or the supply amount of the solution and the droplet size of the supplied solution may be increased.

Alternatively, if the plastic particle size measured in the step of measuring the plastic particle size (S300) is the same as the plastic particle size reference value set and stored in the step of setting the reference value and set value in the controller (S100), the reference value and set value in the control unit The reference value and set value set in the step of setting (S100) may be maintained.

Although the above has been described with reference to preferred embodiments of the present invention based on the drawings, those skilled in the art can vary the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. It will be understood that it can be modified and changed accordingly.

100: waste plastic treatment system
10: precipitation reactor
11: body
12: agitator
13: non-solvent inlet
14: non-solvent 14': sleep of non-solvent
15: recycled plastic particles
20: solution supply unit
21: tank
22: Euro
23, 23', 23”: spray nozzle
24: distribution port
25: main pipe 26, 26', 26”: distribution pipe
30: measuring part
31: investigation department
32: scattered light detector
33: particle size calculation unit
40: control unit
50: aqueous electrolyte solution
51: concentration measuring unit

Claims (10)

A precipitation reactor in which non-solvent is stored and recycled plastic particles are precipitated; and
Waste plastic treatment system comprising a solution supply unit equipped with a spray nozzle for spraying a solution in which the waste plastic is dissolved in the precipitation reactor. The method according to claim 1, wherein the solution supply unit comprises a tank for storing the solution and a flow path connecting the tank and the injection nozzle,
Wherein the injection nozzle is provided at an end of the flow path. The waste plastic treatment system according to claim 1, further comprising a flow rate controller for adjusting the injection amount of the solution using a valve. The method according to claim 2, wherein the passage is drawn into the upper surface of the precipitation reactor,
Wherein the injection nozzle injects the solution toward the surface of the non-solvent. The method according to claim 2, wherein the passage is drawn into the side of the precipitation reactor,
One or more distribution ports are provided on the side of the flow path,
The waste plastic treatment system of claim 1 , wherein the injection nozzles are coupled to the one or more distribution ports, respectively, and inject the solution toward the surface of the non-solvent. The method according to claim 2, wherein the passage is a main pipe drawn into the side of the precipitation reactor; And one or more distribution pipes provided on the side of the main pipe,
Wherein the injection nozzles are coupled to the ends of the one or more distribution pipes, respectively, and inject the solution toward the surface of the non-solvent. The waste plastic treatment system of claim 1, wherein the precipitation reactor further comprises a main body for storing the non-solvent and the precipitated recycled plastic particles, and an agitator positioned in the main body to mix the non-solvent and the solution by rotation. . The waste plastic treatment system of claim 1, further comprising a measuring unit for measuring the size of the recycled plastic particles. The method according to claim 8, wherein the measurement unit includes an irradiation unit for irradiating laser or light onto the recycled plastic particles, a scattered light detector for detecting scattered light scattered while the laser or light passes through the recycled plastic particles, and a change in intensity or angle of the scattered light. Waste plastic treatment system comprising a particle size calculation unit for calculating the size of the recycled plastic particles based on. A waste plastic treatment method comprising the step of precipitating recycled plastic particles by spraying a solution in which waste plastic is dissolved in a precipitation reactor in which non-solvent is stored.