JP2007190481A - Crushing method of waste plastic and crushing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crushing method of waste plastics which reduces the failure of the rotation blade and fixed blade of a crushing machine and the cloggings of a screen to enhance the operability of the crushing machine, and to provide a crushing apparatus. <P>SOLUTION: The crushing apparatus crushes the waste plastics 2 with the rotary blade 5 and the fixed blade 6 arranged in the crushing machine 1 and discharges the crushed waste plastics 8 through the screen 7. In the crushing method of the waste plastics, the waste plastics 2 is crushed by rotating the rotary blade 5 at a low speed of 60-150 rpm to crush the waste plastics 2 and discharges the crushed waste plastics 8 by vertically carrying out the air-suction with a pneumatic tube 10 in the crushing machine 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a waste plastic crushing method and crushing apparatus for finely crushing waste plastic used as a coke raw material.

  Plastic general waste is used for producing coke raw materials (see Patent Document 1).

  FIG. 4 is a schematic view showing a process for producing a coke raw material from a conventional waste plastic.

  In FIG. 4, the plastic general waste of the receiving / inputting means 11 of the waste plastic processing line is separated by the unpacking / breaking bag / rough crusher 12, and the wind sorter 13, the manual sorting conveyor 14, the rough crusher 15, The magnetic separator 16, the non-ferrous metal separator 17, the vibrating sieve 18, and the wind separator 19 remove foreign matters, metals, and non-metals to form a film-like light plastic waste. The waste obtained by crushing the waste with a crusher 20 is reduced in volume by a volume reduction molding machine 21 to produce a waste plastic molded product 22 and supplied to a coke oven as a coke raw material.

  As a waste plastic crusher, a crusher equipped with a rotating rotary blade and a fixed blade and a screen for sieving the waste plastic crushed below them is used (see Patent Document 2).

  FIG. 5A is a schematic view showing an example of a conventional crusher, and FIG. 5B is a cross-sectional view of the screen.

In FIG. 5A, a rotating rotor 24 is disposed in the crushing chamber 23 in the crusher, a plurality of rotating blades 25 are disposed in parallel on the outer peripheral surface of the rotating rotor 24, and the rotating rotor 24 is sandwiched between them. A fixed blade 26 is provided. A screen member 27 is disposed in the crushing machine body at a position below the rotation locus of the rotary blade 25. The waste plastic 29 put into the crushing chamber 23 is brought to the center by the pusher 28 and crushed by the rotary blade 25 and the fixed blade 26 that rotate at high speed. The crushed waste plastic 30 passes through the screen 27 and is discharged. As shown in FIG. 5B, the holes 31 formed in the screen 27 through which the crushed waste plastic 30 passes are provided in a straight line having the same width in the vertical direction.
JP 2001-187406 A JP 2005-144265 A

  Plastic wastes are often discharged from households, and therefore often contain foreign substances that are easily ignited such as lighters and lithium batteries, and hard foreign substances such as metals. In the crusher used in the process for producing the coke raw material from the conventional waste plastic as shown in FIG. 4, the cutter is easily damaged by a hard foreign substance because of high speed rotation (200 rpm or more). Further, there are many cases in which finely crushed materials are clogged without passing through the screen, or waste plastic is welded and clogged due to high-speed rotation. Therefore, since the crusher was frequently stopped in order to replace the rotary blade or the fixed blade or to remove the clogging of the screen, there was a problem that the operation rate of the crusher was poor.

  Further, in the conventional high-speed crusher, the waste plastic can be finely broken, for example, 10 mm or less, and hardly crush.

  In addition, when a lighter, lithium battery, or the like was mixed, the fire was ignited by frictional heat during shearing due to high speed rotation, and the risk of fire was high.

  Therefore, the present invention provides a waste plastic crushing method and a crushing apparatus that can improve the operation rate of the crusher by reducing breakage of the rotary blade and fixed blade of the crusher and clogging of the screen. is there.

  The waste plastic crushing method of the present invention is a waste plastic crushing method in which waste plastic is crushed by a rotating rotary blade and a fixed blade arranged in a crusher, and the crushed waste plastic is discharged through a screen. The waste plastic is crushed by rotating the rotary blade at a low speed of 60 rpm to 150 rpm, and the crushed waste plastic is discharged by aspirating the inside of the crusher in the vertical direction.

  In the waste plastic crusher of the present invention, a rotating rotor having a rotating blade that rotates at a low speed of 60 rpm to 150 rpm is disposed in the lower portion of the crushing chamber that receives the waste plastic, and the fixed blade is crushed across the rotating rotor. A crushed waste plastic that is provided on the side wall of the chamber and has a through-hole formed in the lower part of the rotating rotor through which the waste plastic crushed by the rotary blade and the fixed blade is passed. A discharge chamber for discharging air is provided, and an air feed pipe for sucking air from the crushing chamber through the screen to the discharge chamber is connected to the discharge chamber. You may form the cross section of the said through-hole in the shape which spreads downward at the downward direction.

  In the present invention, since the rotary blade is rotated at a speed about 1/3 that of an existing high-speed crusher, the blade is not easily damaged, waste plastic is not welded during shearing, and a lithium battery or the like is used. Even if it is mixed, there is little risk of fire. Moreover, it becomes possible to crush to about 10 mm or less by low speed rotation.

  Also, since air is sucked in, the cooling effect prevents welding of waste plastic due to frictional heat during shearing, and the suction effect promotes the passage of the crushed waste plastic through the screen and prevents clogging of the screen. Furthermore, by making the through-hole of the screen into a conical shape that spreads downward toward the bottom, the crushed waste plastic that is aspirated by air can easily pass through.

  1 is a cross-sectional view showing an outline of a crushing apparatus used in the present invention, FIG. 2 (a) is a plan view showing the arrangement of rotating blades and fixed blades, (b) is a front cross-sectional view, and FIG. 3 (a) is a screen. (B) is sectional drawing of a through-hole.

  In FIG. 1, a pusher 3 for pushing the roughly crushed waste plastic 2 charged into the crushing chamber in the central direction is disposed at a side portion of the crushing chamber 1 opened at the top where waste plastic is charged. The pusher 3 is moved forward and backward by a hydraulic cylinder 3a.

  A crushing rotor 4 is disposed in the lower part of the crushing chamber. A rotary blade 5 is provided on the surface of the crushing rotor 4, and a fixed blade 6 is disposed in the crushing chamber with the rotary rotor 4 interposed therebetween. As shown in FIG. 2, the rotary blades 5 are arranged in a staggered manner, and enter the blade grooves 6 a formed in the fixed blade 6 according to the pitch of the rotary blades 5 to shear waste plastic. In the present invention, the rotary rotor 4 is rotated at a low speed (about 60 rpm to 150 rpm) which is about 1/3 of the conventional high speed (200 rpm or more). By rotating at a low speed, it is possible to reduce the damage to the blade due to the biting of foreign matter. In addition, since the frictional heat at the time of shearing can be reduced by low-speed rotation, welding of waste plastic can be prevented, and there is a risk of ignition due to crushing when a lighter or lithium battery is mixed. Can be reduced.

  A screen 7 is arranged so as to surround the lower side of the rotating rotor 4. As shown in FIG. 3, the screen 7 has a plurality of through holes 7 a for allowing the crushed waste plastic 8 to pass therethrough. The through hole 7a is about 15 mm or less.

  The through-hole 7a is formed in a conical shape with a taper extending downward in the passing direction of the crushed waste plastic 8. The waste plastic 8 crushed by the downwardly widening through-hole 7a is more easily passed by air suction than the conventional straight hole having the same width in the vertical direction shown in FIG. 5B.

  A discharge chamber 9 in which the crushed waste plastic 8 that has passed through the through-hole 7a of the screen 7 falls is formed at the lower part of the screen 7 in the crushing chamber. The discharge chamber 9 is air-suctioned by a fan (not shown), The crushed waste plastic 8 is aired through the air feed tube 10 and discharged. The discharge chamber 9 is sucked at a fan static pressure of about 5 to 8 kPa. The air sucked from the upper opening of the crushing chamber 1 is sucked through the through hole 7a of the screen 7. Air is sucked from the crushing chamber 1 through the screen 7 to the discharge chamber 9 to prevent welding of the waste plastic during crushing, and the through holes 7a of the waste plastic 8 crushed by the suction effect Passing is promoted, and clogging of the screen 7 can be prevented.

It is sectional drawing which shows the outline of the crushing apparatus used in this invention. (A) is a top view which shows arrangement | positioning of a rotary blade and a fixed blade, (b) is front sectional drawing. (A) is a partial perspective view of a screen, (b) is sectional drawing of a through-hole. It is the schematic which shows the process of manufacturing a coke raw material from the conventional waste plastic. (A) is the schematic which shows an example of the conventional crusher, (b) It is sectional drawing of a screen.

Explanation of symbols

1: Crushing chamber 2: Waste plastic 3: Pusher 4: Crushing rotor 5: Rotary blade 6: Fixed blade 7: Screen 6a: Blade groove 7a: Through hole 8: Crushed waste plastic
9: Discharge chamber 10: Pneumatic pipe 11: Receiving / inputting means 12: Unpacking / breaking bag / rough crusher 13: Wind sorter 14: Manual sorting conveyor
15: Coarse crusher 16: Magnetic sorter 17: Non-ferrous metal sorter 18: Vibrating sieve 19: Wind sorter 20: Crusher 21: Volume reduction molding machine 22: Waste plastic molding 23: Crushing chamber 24: Rotating rotor 25 : Rotating blade 26: fixed blade 27: screen member 28: pusher 29: waste plastic 30: crushed waste plastic 31: hole

Claims (3)

In the crushing method of waste plastic, which crushes waste plastic with a rotating rotary blade and fixed blade arranged in the crusher, and discharges the crushed waste plastic through a screen,
A method for crushing waste plastic, wherein the waste plastic is crushed by rotating the rotary blade at a low speed of 60 rpm to 150 rpm, and the crushed waste plastic is discharged by aspirating the inside of the crusher in the vertical direction.   A rotating rotor having a rotating blade that rotates at a low speed of 60 rpm to 150 rpm is disposed in the lower part of the crushing chamber that receives the waste plastic, and a fixed blade is provided on the side wall of the crushing chamber with the rotating rotor interposed therebetween. A screen having a number of through-holes through which waste plastic crushed by a rotating blade and a fixed blade is passed is arranged, and a discharge chamber is provided at the bottom of the screen to discharge crushed waste plastic that has passed through the screen. In addition, a waste plastic crusher characterized in that an air feed pipe for sucking air from the crushing chamber through the screen to the discharge chamber is connected.   3. The waste plastic crusher according to claim 2, wherein the through-hole has a cross-sectional shape extending downward.

Images