JP2019065092A - Granulator and granulating method - Google Patents

Abstract

To provide a method capable of granulating even in the case where various kinds of plastic products are mixed.SOLUTION: A granulator 1 includes: a first extruder 2; a MFR measurement device 5: a second feeder (a peroxide feed part) 34; a second extruder 6; and a pelletizer 7. Various waste plastic products are fed from a first feeder 13 to the first extruder 2. The plastic products are molten in the first extruder 2 and extruded. In the MFR measurement device 5, a MFR value of the molten plastics is measured. Based on the measured MFR value, an addition amount of a peroxide to be added to the second extruder 6 is determined. The peroxide of the determined addition amount is added from the second feeder to the second extruder. The molten plastics and peroxide are extruded from the second extruder 6 to the pelletizer 7. In the pelletizer 7, granular plastic is produced.SELECTED DRAWING: Figure 1

Description

  TECHNICAL FIELD The present invention relates to a granulator and a granulating method for granulating unnecessary plastic (waste plastic) such as used products and wastes from manufacturing processes into particles (pellets) as regenerating material.

  BACKGROUND ART Conventionally, recycling has been carried out using waste plastic that has been disposed of as a raw material for plastic. The waste plastic is melted and processed into granular plastic (pellets) so that it can be easily used as a plastic raw material. As this processing method, for example, methods described in Patent Documents 1 to 3 have been proposed.

Unexamined-Japanese-Patent No. 2004-25734 JP 2007-90528 A Patent No. 6120393

  There are various types of waste plastic such as soft, hard, extrusion molded products, injection molded products, sheets and films even though they are similar plastic. These materials have various forms and physical properties, and they have different MFR (melt flow rate) values. In addition, waste plastic contains a mixture of different additives, fillers and the like. When such waste plastics having different MFR values etc. are mixed, it is difficult to granulate according to the conventional granulation method, and it may be processed after separating waste plastics to some extent for each form in advance Alternatively, the pellet after granulation needs to be made uniform with a tumbler or the like. However, it goes without saying that sorting and homogenization require considerable time and cost.

  An object of the present invention is to provide a granulator and a granulating method capable of granulating pellets having a desired MFR value even when waste plastics having different MFR values are mixed.

  The present invention is a granulator for processing waste plastic into particles, and a first extruder for melting and extruding input waste plastic, MFR value of the molten plastic extruded from the first extruder MFR measuring device, peroxide input part for adding peroxide to the molten plastic for which the MFR value was measured, second extruder for mixing and extruding the peroxide and the molten plastic added And a molding apparatus for granulating using the molten plastic extruded from the second extruder. Here, the granulation according to the present invention means converting the plastic introduced into the first extruder into granular plastic (for example, pellets).

  According to the above configuration, the MFR measuring device can be arranged inline, so while measuring the MFR value of the molten plastic with the MFR measuring device, it is continuous while adding an appropriate amount of peroxide so as to achieve the desired MFR value. Can be granulated. By adding the determined amount of peroxide to the molten plastic, granulation can be performed even when various plastic products are mixed. That is, since a polymer resin such as polyolefin can be reduced in molecular weight by peroxide, the MFR value of the waste plastic is monitored by an MFR meter between the first extruder and the second extruder, and the monitored MFR is obtained. Depending on the amount of peroxide input (addition amount) per unit time, the pellet has a desired MFR value, even in the case where waste plastic with variation in MFR value is used by adjusting and setting it. Can be granulated.

  In the above-mentioned configuration, by controlling the peroxide input portion, it is added from the peroxide input portion so that a molten plastic having a desired MFR value can be obtained based on the MFR value measured by the MFR measuring device. Preferably, a control unit is provided to adjust the amount of peroxide added.

  The control unit can automatically control the amount of peroxide added to the molten plastic from the peroxide input unit.

  In the above-mentioned composition, it is preferred to have a filter part which removes an impurity contained in fusion plastic extruded from the 1st extruder. Here, the impurities include those other than the desired plastic. The impurities include, for example, inorganic substances such as fillers. The inorganic substances include, for example, calcium carbonate, aluminum foil, paper and the like.

  The melted plastic from which the impurities have been removed is sent to the MFR measuring device. Therefore, the MFR value of the molten plastic from which the impurities have been removed can be measured. This improves the measurement accuracy of the MFR value. By determining the amount of peroxide added based on this MFR value, the accuracy of the amount of peroxide added is improved. This improves the accuracy of making the molten plastic into a desired MFR. Moreover, it can suppress that an impurity is contained in the granulated material obtained by a granulator. This improves the quality of the granulated material. Furthermore, a plastic material to which a desired function is added can be manufactured by newly adding an additive, a filler and the like in the second extruder. In addition, masterbatches as plastic colorants can also be produced from waste plastic by incorporating pigments in a second extruder.

  In the above configuration, it is preferable to include a flow regulator disposed downstream of the first extruder and upstream of the second extruder in the flow direction of the molten plastic extruded from the first extruder. .

  The flow controller can adjust the flow rate of the molten plastic supplied to the second extruder. Thereby, the supply amount of the molten plastic to the second extruder can be known, the addition amount of peroxide can be adjusted more accurately, and the supply can be performed automatically.

  In addition, when the flow rate adjuster is disposed upstream of the MFR measuring device, the measurement of the MFR value can also be performed with higher accuracy.

Furthermore, when using a flow regulator together with the filter unit, it is preferable to dispose the flow regulator downstream of the filter unit. That is, although the flow rate of the resin extruded from the first extruder is lost in the filter unit, the flow regulator can supply the melted plastic of the flow rate-adjusted amount to the second extruder. The addition amount of peroxide per unit time can be set by the supply amount at this time and the MFR value.
In addition, as a flow volume regulator, a gear pump etc. can be used preferably, for example.

  The granulation method of the present invention comprises a first extrusion step of melting and extruding waste plastic, an MFR measurement step of measuring the MFR value of the molten plastic extruded in the first extrusion step, and a measured MFR value The amount of peroxide to be added is determined based on the amount of peroxide, and the determined amount of peroxide to be added is added to the molten plastic extruded in the first extrusion step, the peroxide added step, the added peroxide and the molten plastic And a second extrusion step of kneading and extruding, and a forming step of obtaining granular plastic using the molten plastic extruded in the second extrusion step.

  According to the above configuration, the MFR value of the molten plastic is measured. By using this MFR value, it is possible to determine the amount of peroxide added to obtain a molten plastic having the desired MFR value. By adding the determined amount of peroxide to the molten plastic, granulation can be performed even when various waste plastics are mixed.

  In the above configuration, it is preferable to have an impurity removing step of removing impurities contained in the molten plastic extruded in the first extrusion step after the first extrusion step and before the MFR measurement step. .

  After the impurities contained in the molten plastic are removed in the impurity removing step, the MFR value of the molten plastic is measured in the MFR measuring step. This improves the measurement accuracy of the MFR value. By determining the amount of peroxide added based on this MFR value, the accuracy of the amount of peroxide added is improved. This improves the accuracy of making the molten plastic into a desired MFR. Moreover, it can suppress that an impurity is contained in the granulated material obtained. This improves the quality of the granulated material.

  In the above configuration, after the first extrusion step and before the second extrusion step, a transfer step of transferring the molten plastic extruded in the first extrusion step to the next step by a predetermined amount It is preferable to have.

  As a result, the amount of peroxide added in the peroxide charging step can be adjusted more accurately, and can be supplied automatically. When the transfer step is performed before the MFR measurement step, the measurement of the MFR value can be performed with higher accuracy. Furthermore, when using the transfer step together with the impurity removal step, it is preferable to carry out the transfer step after the impurity removal step, and adjust the flow rate of molten plastic lost in the impurity removal step in the transfer step to the next step. The amount of peroxide added per unit time in the peroxide charging step can be set according to the predetermined amount at this time and the measured MFR value.

  According to the invention, the MFR value of the molten plastic is determined. By using this MFR value, it is possible to determine the amount of peroxide added to obtain a molten plastic having the desired MFR value. By adding the determined amount of peroxide to the molten plastic, granulation can be performed even when various plastic products are mixed.

It is a cross-sectional schematic diagram of the granulator of 1st Embodiment of this invention. It is a block diagram of a part of structure of the granulator of 1st Embodiment of this invention. It is a flowchart of the granulation method of 1st Embodiment of this invention. It is a cross-sectional schematic diagram of the granulator of 2nd Embodiment of this invention. It is a block diagram of a part of structure of the granulator of 2nd Embodiment of this invention. It is a cross-sectional schematic diagram of the granulator of 3rd Embodiment of this invention. It is a block diagram of a part of structure of the granulator of 3rd Embodiment of this invention.

First Embodiment
The granulator 1 is, as shown in FIG. 1, a first extruder 2, a filter unit 3, a flow rate adjuster 4, an MFR measuring device 5, a second extruder 6, and a pelletizer (forming apparatus 7 and the control unit 8 (see FIG. 2). In the direction in which the molten plastic extruded from the first extruder 2 flows, the filter unit 3, the flow rate adjuster 4, the MFR measuring device 5, the second extruder 6, and the pelletizer 7 sequentially from the upstream side It is arranged. The control part 8 is connected to the flow volume regulator 4, the MFR measuring device 5, and the 2nd feeder 34 mentioned later, as shown in FIG.

  As shown in FIG. 1, the first extruder 2 is a single screw extruder. The first extruder 2 has a cylindrical barrel 11 and a screw 12 disposed inside the barrel 11. The screw 12 is disposed coaxially with the barrel 11. The first extruder 2 can be widely used known extruders such as a single screw or twin screw type.

  A first feeder 13 is connected to one end of the first extruder 2 in the longitudinal direction of the first extruder 2. Waste plastic products (waste plastic) and the like are introduced into the first feeder 13. Waste plastic products are crushed and used. In addition, for example, polyolefin, such as polyethylene and polypropylene, can preferably be used as the waste plastic product.

  A heater 14 is disposed on the outer peripheral surface of the barrel 11 from one end to which the first feeder 13 is connected in the longitudinal direction of the first extruder 2 to near the center. The waste plastic product or the like introduced into the barrel 11 from the first feeder 13 is melted by being heated by the heater 14. For example, a heater can be used as the heater 14.

  The filter unit 3 is disposed between the first extruder 2 and the flow regulator 4. The filter unit 3 has a passage 21 and a filter 22 disposed in the middle of the passage 21. The passage 21 is divided by the filter 22 into an area close to the first extruder 2 and an area close to the flow regulator 4. For example, a metal mesh structure may be used as the filter 22. A branch passage 23 branches from the passage 21 upstream of the filter 22 in the flow direction of the molten plastic. The branch passage 23 communicates with the outside of the filter unit 3.

  The flow rate regulator 4 is disposed between the filter unit 3 and the MFR measuring device 5. The flow regulator 4 is disposed downstream of the first extruder 2 and upstream of the second extruder 6 in the direction in which the molten plastic flows. The flow controller 4 adjusts the flow rate of the molten plastic supplied to the MFR measuring device 5 and the second extruder 6. The flow controller 4 may adjust the flow rate of the molten plastic, for example, by pressurizing or depressurizing the molten plastic. For example, a gear pump can be used as the flow rate regulator 4.

  The MFR measuring device 5 is disposed between the flow rate regulator 4 and the second extruder 6 in a pipe P connecting the flow rate regulator 4 and the second extruder 6. The MFR measuring device 5 is disposed inside the pipe P. That is, the MFR measuring instrument 5 is disposed inline. The MFR measuring device 5 measures the MFR value of the molten plastic. As the MFR measuring device 5, for example, a commercially available online type rheometer (online MFR meter for extruder) can be used.

  The second extruder 6 is a twin screw extruder. The second extruder 6 has a barrel 31 and two screws 32 and 33 disposed inside the barrel 31. In addition, the 2nd extruder 6 can use widely well-known extruders, such as a screw type of a 1 axis or a 2 axis | shaft.

  One end of the second extruder 6 in the longitudinal direction of the second extruder 6 is connected to the MFR measuring device 5. Further, a second feeder (peroxide charging unit) 34 is connected to this one end of the second extruder 6. The second feeder 34 communicates with the inside of the barrel 31. The other end of the second extruder 6 is connected to a pelletizer 7.

  Peroxide is fed to the second feeder 34. The control of the second feeder 34 by the control unit 8 automatically adds peroxide from the second feeder 34 to the second extruder 6. The control unit 8 controls the amount of peroxide added. The control unit 8 may control the timing and the like of adding the peroxide.

  The pelletizer 7 has a cutter not shown. In the pelletizer 7, the plastic extruded from the second extruder 6 is cut into a predetermined size by a cutter. This gives a granular plastic. The pelletizer 7 may have a cooler (not shown). In the pelletizer 7, the plastic may be cooled by a cooler prior to cutting the plastic. In addition, in the pelletizer 7, after cutting the plastic, the plastic may be cooled by a cooler. For example, a pelletizer can be used as the pelletizer 7.

  As shown in FIG. 2, the control unit 8 includes a determination unit 41. Based on the MFR value of the molten plastic measured by the MFR measuring device 5, the determination unit 41 sends the second extruder 34 to the second extruder 6 so that the MFR value of the molten plastic becomes the desired MFR value. Determine the amount of peroxide to be added.

  The desired MFR value is not limited. The desired MFR value is, for example, an MFR value that allows the plastic to be extruded smoothly in the second extruder 6. The desired MFR value is, for example, an MFR value at which the second extruder 6 and the pelletizer 7 are not loaded when the plastic passes through the granulator 1. The desired MFR value is, for example, an MFR value capable of kneading the plastic and the additive in the second extruder 6 so that the additive such as the filler is uniformly dispersed in the plastic.

  The determination unit 41 can consider the molten plastic flow rate adjusted by the flow rate regulator 4 or the molten plastic flow rate adjusted by the flow rate regulator 4 when determining the peroxide addition amount. The molten plastic flow rate adjusted by the flow rate regulator 4 is, for example, information sent from the flow rate regulator 4 to the determination unit 41 after the flow rate regulator 4 adjusts the flow rate of the molten plastic. The molten plastic flow rate adjusted by the flow rate regulator 4 is, for example, information sent from the control unit 8 to the flow rate regulator 4 before the flow rate regulator 4 adjusts the flow rate of the molten plastic. The flow controller 4 adjusts the flow rate of the molten plastic so that the flow rate of the molten plastic becomes this flow rate. It is considered that the flow rate of the molten plastic adjusted by the flow rate regulator 4 and the flow rate of the molten plastic adjusted by the flow rate regulator 4 are substantially equivalent to the flow rate of the molten plastic supplied to the second extruder 6 be able to. The determining unit 41 does not have to consider the flow rate of the molten plastic adjusted by the flow rate adjuster 4 or the flow rate of the molten plastic adjusted by the flow rate adjuster 4 when determining the addition amount of peroxide. .

  For example, if the MFR value of the molten plastic measured by the MFR measuring device 5 is much smaller than the desired MFR value, the peroxide addition amount is increased. At this time, when the flow rate of the molten plastic adjusted by the flow rate regulator 4 or the flow rate of the molten plastic adjusted by the flow rate regulator 4 is high, the addition amount of peroxide is extremely increased. When the flow rate of the molten plastic adjusted by the flow rate regulator 4 or the flow rate of the molten plastic adjusted by the flow rate regulator 4 is small, the addition amount of peroxide may not be so large.

  When the MFR value of the molten plastic measured by the MFR measuring device 5 is slightly smaller than the desired MFR value, the amount of peroxide added is reduced. At this time, when the flow rate of the molten plastic adjusted by the flow rate regulator 4 or the flow rate of the molten plastic adjusted by the flow rate regulator 4 is high, the addition amount of peroxide is slightly increased. When the flow rate of the molten plastic adjusted by the flow rate regulator 4 or the flow rate of the molten plastic adjusted by the flow rate regulator 4 is small, the addition amount of peroxide is reduced.

  If the MFR value of the molten plastic measured by the MFR measuring device 5 is larger than the desired MFR value, peroxide may not be added. In this case, the addition amount of peroxide is set to zero.

  The control unit 8 controls the second feeder 34 to adjust the amount of peroxide added from the second feeder 34 to the second extruder 6. The control unit 8 controls the second feeder 34 such that peroxide of the addition amount determined in the determination unit 41 is added from the second feeder 34 to the second extruder 6. By adding peroxide from the second feeder 34 to the second extruder 6, the MFR value of the molten plastic in the second extruder 6 is increased. The higher the MFR value of the molten plastic, the higher the fluidity of the molten plastic.

  The control unit 8 may be able to adjust the flow rate of the molten plastic by controlling the flow rate regulator 4. The flow rate adjuster 4 may receive the target flow rate sent from the control unit 8 and adjust the flow rate of the molten plastic so that the flow rate of the molten plastic becomes the target flow rate. The target flow rate may be set in advance in the flow rate regulator 4. The flow controller 4 may adjust the flow rate of the molten plastic so that the flow rate of the molten plastic becomes a preset target flow rate.

  Next, a method of granulating waste plastic will be described with reference to FIGS. 1 to 3.

  First, as shown in FIG. 1, waste plastic products and the like are introduced from the first feeder 13 into the first extruder 2. Waste plastic products and the like include plural types of plastic products having different melt flow rate (MFR) values. Waste plastic products and the like may be crushed before being supplied to the first extruder 2. Waste plastics are, for example, polyethylene, polyvinyl chloride, polystyrene and polypropylene.

  The waste plastic products and the like input to the first extruder 2 are melted by being heated by the heater 14. While kneading the molten plastic, the first extruder 2 extrudes the molten plastic toward the filter unit 3 (first extrusion step, S1 in FIG. 3).

  In the filter unit 3, the impurities contained in the molten plastic are removed by the filter 22 (impurity removing step, S2 in FIG. 3). If impurities adhere to the filter 22, the filter 22 may be replaced with a new filter. Also, the impurities attached from the filter 22 may be removed. For example, impurities may be removed from the filter 22 manually. Further, the impurity may be discharged to the outside of the filter unit 3 through the branch passage 23 by a suction device or the like.

  The molten plastic that has passed through the filter 22 is sent to the flow controller 4. The flow controller 4 adjusts the flow rate of the molten plastic. As a result, the molten plastic is transferred by a predetermined amount to the MFR measuring device 5 (transfer step, S3 in FIG. 3). The flow rate adjusted by the flow rate regulator 4 is stored in the control unit 8.

  The MFR value of the molten plastic is measured in the MFR measuring device 5 (MFR measuring step, S4 in FIG. 3). The measured MFR value is sent to the control unit 8 (see FIG. 2). The molten plastic is transferred by a predetermined amount to the second extruder 6 (transfer step, S5 in FIG. 3).

  As shown in FIG. 2, in the control unit 8, the determination unit 41 determines the amount of peroxide to be added based on the measured MFR value. The determining unit 41 may consider the flow rate of the molten plastic adjusted by the flow rate adjuster 4 when determining the amount of peroxide added.

  The control unit 8 controls the second feeder 34 to add peroxide of the addition amount determined in the determination unit 41 from the second feeder 34 to the second extruder 6 (peroxide charging step, S6 of FIG.

  In the second extruder 6, peroxide and molten plastic are kneaded (see FIG. 1). Here, additives such as a filler and a coloring material may be added to the second extruder 6. The peroxide and the molten plastic thus kneaded are extruded to the pelletizer 7 (second extrusion step, S7 in FIG. 3).

  In the pelletizer 7, the plastic is cut into a predetermined size. As a result, granular plastic is obtained (pelletizing (forming step), S8 in FIG. 3).

  As described above, according to this embodiment, the following effects can be obtained.

  Before adding peroxide to the molten plastic, the MFR value of the molten plastic is measured by the MFR measuring device 5. By using the measured MFR value, it is possible to determine the amount of peroxide added to obtain a molten plastic of the desired MFR value. By adding the determined amount of peroxide to the molten plastic, the MFR value of the molten plastic can be brought close to the desired MFR value. Thereby, the plastic can be granulated even when various plastic products are mixed.

  Further, since the MFR measuring instrument 5 can be arranged in line, while the MFR value of the molten plastic is measured by the MFR measuring instrument 5, it is continuously added while adding an appropriate amount of peroxide so as to obtain a desired MFR value. Can be granulated. By adding the determined amount of peroxide to the molten plastic, granulation can be performed even when various plastic products are mixed. That is, since the polymer resin such as polyolefin can be reduced in molecular weight by peroxide, the MFR value of the waste plastic is monitored by the MFR measuring device 5 between the first extruder 2 and the second extruder 6 to monitor By adjusting and setting the peroxide input amount (addition amount) per unit time according to the MFR, a desired MFR value can be obtained even when waste plastic having a variation in MFR value is used as a raw material. It can be made plastic.

  Further, the control unit 8 controls the second feeder (peroxide feeding unit) 34 to automatically add peroxide from the second feeder 34 to the second extruder 6. Furthermore, the amount of peroxide added is the amount determined using the MFR value (measured value). Therefore, the amount of peroxide added to the second extruder 6 can be automatically controlled by the control unit 8.

  Further, in the filter unit 3, impurities contained in the molten plastic extruded from the first extruder 2 are removed. Thereby, the molten plastic from which the impurities have been removed is sent to the MFR measuring device 5. Therefore, the MFR value of the molten plastic from which the impurities have been removed can be measured in the MFR measuring device 5. Therefore, the measurement accuracy of the MFR value is improved. By determining the amount of peroxide added based on this MFR value, the accuracy of the amount of peroxide added is improved. This improves the accuracy of making the molten plastic into a desired MFR. Moreover, it can suppress that an impurity is contained in the granulated material obtained by the granulator 1. This improves the quality of the granulated material.

  The flow controller 4 can adjust the flow rate of the molten plastic supplied to the second extruder 6. Thereby, the supply amount of the molten plastic to the second extruder 6 can be known, the addition amount of the peroxide can be adjusted more accurately, and the supply can be performed automatically. Further, when the flow rate regulator 4 is disposed upstream of the MFR measuring instrument 5, the measurement of the MFR value can also be performed with higher accuracy. Furthermore, when using the flow rate regulator 4 in combination with the filter unit 3, the flow rate regulator 4 is disposed downstream of the filter unit 3 so that the flow rate of molten plastic lost in the filter unit 3 can be Since the flow rate can be adjusted and supplied downstream, the amount of molten plastic fed per unit time to the second extruder 6 can be determined, and the amount of peroxide added per unit time can be determined by this amount of feed and the MFR value. The amount can be set more accurately.

  Further, even if the flow rate of the molten plastic is reduced in the filter portion 3 due to clogging of the filter 22 or the like, the flow rate of the molten plastic can be increased by the flow rate adjuster 4.

  Further, by adding an additive such as a filler to the second extruder 6, a granular plastic having a desired function can be obtained. Further, by adding a coloring material such as a pigment to the second extruder 6, a granular plastic (masterbatch) whose inside is colored is obtained.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIGS. 4 and 5. The second embodiment differs from the first embodiment in that the granulator 101 includes a flow rate measuring device 104 instead of the flow rate regulator 4. In addition, about the structure same as 1st Embodiment mentioned above, the same code | symbol is used and the description is abbreviate | omitted suitably.

  The granulator 101 is provided with a flow rate measuring device 104 as shown in FIG. The flow rate measuring device 104 is disposed between the filter unit 3 and the MFR measuring device 5. In the flow direction of the molten plastic, the filter unit 3, the flow rate measuring device 104, the MFR measuring device 5, the second extruder 6, and the pelletizer 7 are disposed in this order from the upstream side. The flow rate measuring device 104 is disposed downstream of the first extruder 2 and upstream of the second extruder 6 in the flow direction of the molten plastic. The flow rate measuring device 104 is connected to the control unit 8 (see FIG. 5).

  The flow rate measuring device 104 measures the flow rate of the molten plastic. The flow rate of the molten plastic measured by the flow rate measuring device 104 is sent to the control unit 8. The flow rate of the molten plastic measured by the flow rate measuring device 104 can be considered to be substantially equal to the flow rate of the molten plastic supplied to the second extruder 6.

  The determination unit 41 of the control unit 8 determines the amount of peroxide to be added based on the MFR value measured by the MFR measuring device 5 (see FIG. 5). The determination unit 41 may consider the flow rate of the molten plastic measured by the flow rate measuring device 104 when determining the amount of peroxide to be added. The determination unit 41 does not have to consider the flow rate of the molten plastic measured by the flow rate measuring device 104 when determining the peroxide addition amount. The method of determining the peroxide addition amount by the determination unit 41 is, for example, the same as the method of determining the peroxide addition amount illustrated in the first embodiment. In the method of determining the addition amount of peroxide exemplified in the first embodiment, instead of “the flow rate of the molten plastic adjusted by the flow rate regulator 4 or the flow rate of the molten plastic adjusted by the flow rate regulator 4” , “The flow rate of the molten plastic measured by the flow meter 104”.

  According to the granulator and granulation method of the second embodiment, as in the granulator and granulation method of the first embodiment, the plastic can be granulated even when various plastic products are mixed. In addition, when determining the addition amount of peroxide in the determination unit 41, the accuracy of setting the MFR of the molten plastic to a desired MFR is improved by considering the flow rate measured by the flow rate measuring device 104.

Third Embodiment
Next, a third embodiment of the present invention will be described with reference to FIG. 6 and FIG. The third embodiment is different from the first embodiment in that the flow rate adjuster 4 of the first embodiment adjusts the flow rate of the molten plastic, whereas the flow rate adjuster 204 of the third embodiment adjusts the flow rate of the molten plastic And flow rate measurement. In addition, about the structure same as 1st Embodiment mentioned above, the same code | symbol is used and the description is abbreviate | omitted suitably.

  The granulator 201 is provided with a flow rate regulator 204 as shown in FIG. The flow rate regulator 204 is disposed between the filter unit 3 and the MFR measuring device 5. The flow rate regulator 204 is connected to the control unit 8 (see FIG. 7).

  The flow controller 204 measures the flow rate of the molten plastic transferred to the MFR measuring device 5 and adjusts the flow rate of the molten plastic transferred to the MFR measuring device 5. The flow rate regulator 204 may only adjust the flow rate of the molten plastic transferred to the MFR measuring instrument 5. Also, the flow controller 204 may only measure the flow rate of the molten plastic transferred to the MFR measuring device 5.

  The controller 8 controls only the flow rate of the molten plastic by controlling the flow rate regulator 204, 2) performs only the flow rate measurement of the molten plastic, or 3) the flow rate measurement of the molten plastic and the molten plastic It is possible to switch to either operation of performing both of flow adjustment.

1) When the flow rate adjuster 204 only adjusts the flow rate of the molten plastic, the determination unit 41 determines the amount of peroxide to be added based on the MFR value measured by the MFR measuring device 5. It is possible to consider the flow rate of the molten plastic adjusted by or the flow rate of the molten plastic adjusted by the flow rate regulator 204.
2) When the flow rate adjuster 204 only measures the flow rate of the molten plastic, the determination unit 41 determines the amount of peroxide to be added based on the MFR value measured by the MFR measuring device 5. The flow rate of the molten plastic measured by can be taken into account.
3) The determination unit 41 adjusts the flow rate when determining the amount of peroxide to be added based on the MFR value measured by the MFR measuring device 5 when performing both the flow rate measurement of the molten plastic and the flow rate adjustment of the molten plastic The flow rate of molten plastic adjusted by the vessel 204 or the flow rate of molten plastic adjusted by the flow regulator 204 can be considered.
In the cases of 1) and 3), when the determining unit 41 determines the peroxide addition amount based on the MFR value measured by the MFR measuring device 5, the determining unit 41 adjusts the amount of molten plastic adjusted by the flow rate adjuster 204. The flow rate and the flow rate of the molten plastic adjusted by the flow rate regulator 204 may not be considered. Further, in the case of 2), when determining the peroxide addition amount based on the MFR value measured by the MFR measuring device 5, the determining unit 41 takes into consideration the flow rate of the molten plastic measured by the flow controller 204. You do not have to. The method of determining the peroxide addition amount by the determination unit 41 is, for example, the same as the method of determining the peroxide addition amount illustrated in the first embodiment.

  According to the granulator and the granulation method of the third embodiment, similar to the granulator and the granulation method of the first embodiment, the plastic can be granulated even when various plastic products are mixed. In addition, when determining the addition amount of peroxide in the determination unit 41, the accuracy of setting the MFR of the molten plastic to a desired MFR is improved by considering the flow rate measured by the flow rate regulator 204.

  As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is indicated not by the above description but by claims, and includes all modifications within the meaning and scope equivalent to claims.

  For example, the granulator 1 of the first embodiment, the granulator 101 of the second embodiment, and the granulator 201 of the third embodiment include the control unit 8. The control unit 8 controls the second feeder 34 to automatically add peroxide from the second feeder 34 to the second extruder 6. Further, the amount of peroxide added from the second feeder 34 to the second extruder 6 is automatically adjusted. However, the granulator does not have to have the control unit. When the granulator does not have a control unit, the operator determines the amount of peroxide added based on the MFR value (the value measured by the MFR measuring instrument), and the peroxide of the determined amount is added to the second feeder. It may be added to the second extruder 6 through 34. That is, peroxide may be manually added from the second feeder 34 to the second extruder 6. Also, the amount of peroxide added from the second feeder 34 to the second extruder 6 may be manually adjusted.

  The granulator 1 of the first embodiment, the granulator 101 of the second embodiment, and the granulator 201 of the third embodiment are provided with the filter unit 3. However, the granulator does not have to have a filter part.

  In the granulator 1 of the first embodiment, the granulator 101 of the second embodiment, and the granulator 201 of the third embodiment, the filter unit 3 includes the first extruder 2 and the flow regulator 4. It is arranged between. However, the filter unit 3 may be provided, for example, in the first extruder 2. For example, the filter unit may be disposed in the vicinity of the inlet of the first extruder 2, that is, the boundary between the first feeder 13 and one end of the first extruder 2. In addition, a filter portion may be disposed at the outlet of the first extruder 2, that is, at the other end of the first extruder 2.

  In addition, the granulator 1 of the first embodiment includes the flow rate adjuster 4. The granulator 201 of the third embodiment is provided with a flow rate adjuster 204. However, the granulator does not have to have a flow regulator.

  Further, in the granulator 1 of the first embodiment, the flow rate adjuster 4 is disposed between the filter unit 3 and the MFR measuring device 5. In the granulator 201 of the third embodiment, the flow rate regulator 204 is disposed between the filter unit 3 and the MFR measuring instrument 5. However, the flow regulator may be disposed between the MFR measuring device 5 and the second extruder 6.

  Moreover, the granulator 101 of 2nd Embodiment is provided with the flow measuring device 104. FIG. However, the granulator does not have to have a flow meter.

  Moreover, in the granulator 101 of the second embodiment, the flow rate measuring device 104 is disposed between the filter unit 3 and the MFR measuring device 5. However, the flow rate measuring device 104 may be disposed between the MFR measuring device 5 and the second extruder 6.

  Moreover, the granulator 201 of 3rd Embodiment is equipped with the flow control device 204 which can perform the flow control of molten plastic, and the flow measurement of molten plastic. However, the granulator may include a flow controller capable of adjusting the flow rate of the molten plastic, and a flow rate measuring device capable of measuring the flow rate of the molten plastic. For example, in the granulator, a flow rate measuring device and a flow rate adjuster may be disposed between the first extruder 2 and the second extruder 6. In this case, if the flow meter and the flow controller are arranged in order from the upstream with respect to the direction in which the molten plastic flows, it is determined from the flow measured by the flow meter whether the flow controller needs the flow adjustment. can do.

  In the granulator 1 of the first embodiment, the granulator 101 of the second embodiment, and the granulator 201 of the third embodiment, the outer peripheral surface of the barrel 11 of the first extruder 2 is The heater 14 is disposed from the one end where the first feeder 13 is connected to the longitudinal direction of the extruder 2 to the vicinity of the center. However, the heater may be disposed on the outer peripheral surface of the barrel 11 from one end to the other end in the longitudinal direction of the first extruder 2.

  Moreover, in the granulator 1 of the first embodiment, the granulator 101 of the second embodiment, and the granulator 201 of the third embodiment, the first extruder 2 is a single screw type extruder. However, the first extruder may be a twin screw extruder. Also, the first extruder may not be screw type.

  Moreover, in the granulator 1 of the first embodiment, the granulator 101 of the second embodiment, and the granulator 201 of the third embodiment, the second extruder 6 of the first embodiment has a twin screw. It is a mold extruder. However, the second extruder may be a single screw extruder. Also, the second extruder may not be of the screw type.

  Moreover, although the pelletizer 7 was used as a shaping | molding apparatus in 1st Embodiment, 2nd Embodiment, and 3rd Embodiment, a shaping | molding apparatus is not limited to a pelletizer.

1,101,201 Granulator 2 First extruder 3 Filter part 4,204 Flow regulator 5 MFR measuring device 6 Second extruder 7 Pelletizer (forming device)
DESCRIPTION OF SYMBOLS 8 control part 11, 31 barrel 12, 32 and 33 screw 13 1st feeder 14 heater 22 filter 34 2nd feeder (peroxide input part)
41 determination unit 104 flow meter

Claims (7)

A granulator that processes waste plastic into particles,
The first extruder that melts and extrudes input waste plastic,
MFR measuring device for measuring the MFR value of the molten plastic extruded from the first extruder,
A peroxide charging unit for adding peroxide to the molten plastic of which the MFR value is measured;
A second extruder for mixing and extruding the peroxide added and the molten plastic;
A granulator comprising a molding device for granulating using the molten plastic extruded from the second extruder.   Peroxide addition added from the peroxide input part so as to obtain a molten plastic of a desired MFR value based on the MFR value measured by the MFR measuring device by controlling the peroxide input part A granulator according to claim 2, characterized in that it comprises a control for adjusting the amount.   The granulator according to claim 1 or 2, further comprising a filter portion for removing impurities contained in the molten plastic extruded from the first extruder.   A method according to claim 1, characterized in that it comprises a flow regulator arranged downstream of the first extruder and upstream of the second extruder in the direction of flow of the molten plastic extruded from the first extruder. Granulator according to any one of 1 to 3. A first extrusion process for melting and extruding waste plastic,
MFR measurement step of measuring the MFR value of the molten plastic extruded in the first extrusion step;
A peroxide charging step of determining the amount of peroxide added based on the measured MFR value and adding the determined amount of peroxide to the molten plastic extruded in the first extrusion step;
A second extrusion step of kneading and extruding the added peroxide and the molten plastic;
A granulating method comprising a forming step of obtaining granular plastic using the molten plastic extruded in the second extrusion step.   After the first extrusion process and before the MFR measurement process, the method has an impurity removal process for removing impurities contained in the molten plastic extruded in the first extrusion process. The granulation method as described in 5.   After the first extrusion step and before the second extrusion step, there is a transfer step of transferring the molten plastic extruded in the first extrusion step to the next step by a predetermined amount. The granulation method according to claim 5 or 6.

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