KR20120122871A - Treating method and treating apparatus for expanded urethane - Google Patents

Abstract

PURPOSE: A method and apparatus for treating urethane foam are provided to continuously treat urethane foam while preventing a countercurrent. CONSTITUTION: A method for treating urethane foam comprises: a step of putting urethane foam into a extruder for supplying; a step of heating the urethane foam while extruding the urethane foam by a screw(11s) in the extruder; a step of putting drugs from a drug injection device which is connected to the extruder to the urethane foam into the urethane foam of high temperature and high pressure; and a step of controlling the drug injection device based on a torque value of the screw when monomerizing the urethane foam by circulating the urethane foam into a reaction pipe(12) from the extruder by using high temperature and high pressure field. [Reference numerals] (22) Motor(torque sensor); (AA) Diol; (BB) Urethane; (CC) Monomer; (Za) Supplying; (Zb) Pressing; (Zc) Sealing; (Zd) Reaction

Description

Processing method of foamed urethane and its processing apparatus {TREATING METHOD AND TREATING APPARATUS FOR EXPANDED URETHANE}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for treating foamed urethane for recycling waste of urethane foam used in home appliances, automobiles, buildings, and the like. In particular, the treatment of foamed urethane for treating foamed urethane by a decomposition reaction using a chemical agent A method and a processing apparatus thereof.

In recent years, while environmental issues are becoming more important, waste disposal costs are increasing year by year. The atmosphere for recycling reuse is also increasing for thermosetting resins such as foamed urethane. Several methods of recycling urethane foams have been proposed, and it is conceivable to use a chemical reaction under high temperature and high pressure in order to improve the processing speed thereof.

On the other hand, the waste of foamed urethane has a specific gravity of 0.1 or less and is very bulky, and the method of reduction treatment is important even when chemically treated. In particular, in order to maintain thermal insulation, bubbles are independent and mechanical strength is high. For this reason, it is necessary to reduce the bubble while cutting it. In order to solve this problem, it is proposed to use an extruder.

However, there is a problem that it is difficult to maintain the uniformity of the reaction when the reaction vessel is enlarged in order to maintain the reaction time because of the large volume and the small specific gravity, the supplyability of the material to the extruder is poor, and the raw material is bulky.

In such a situation, the method of compacting decomposition (patent document 1) and the method of compressing while heating (patent document 2) are proposed using a twin screw extruder, using a chemical reaction in it.

Japanese Patent Application Laid-open No. Hei 8-20023 Japanese Patent Application Laid-Open No. 11-138540 Japanese Laid-Open Patent Publication No. 2007-204516 Japanese Laid-Open Patent Publication No. 2005-330365

However, in patent document 1, since the twin screw extruder is used, the cost of an apparatus becomes high. In addition, there is a problem that the reaction time cannot be sufficiently maintained.

In order to solve the problem of this reaction time, patent document 3 attaches a reaction tank to an extruder, and ensures the residence time. However, in this method, since the raw material supplied to the reactor continuously from the extruder is held in the reactor, the discharge of the product from the reactor is not continuous. Therefore, the difference of reaction time corresponding to the time required for supply arises between the raw material initially supplied to the reaction tank, and the raw material last supplied. As a result, the product becomes nonuniform.

On the other hand, as an apparatus for processing crosslinked polyethylene, the apparatus which mounts a reaction tube in an extruder like patent document 4 is proposed.

In the apparatus shown in Patent Document 4, since the product from the reaction tube can be discharged continuously, it is possible to control the reaction time uniformly. In Patent Document 4, when injecting liquid or gas into the extruder at high pressure, it is necessary to first supply only a resin to the extruder to fill the inside of the extruder so that the injected liquid or gas does not leak to the hopper side.

That is, as a 1st subject, when the timing of injecting liquid or gas into an extruder is incorrect, they may leak to the hopper side. Since the extruder is a pressure vessel, there is a problem that it is difficult to confirm where the material is supplied.

In addition, at the start-up stage of the device, a polymer that does not have sufficient drug injected passes through the reaction tube. As a result, the material discharged from the reaction tube contains many unreacted products. In patent document 4, since the raw material which also supplies a product is also assumed to be a polymer, the change of a viscosity is not large. However, in the case where the polyurethane is monomerized, it may be considered that the product becomes a liquid at normal temperature and, in some cases, a gas. In addition, it becomes a gas in a reaction tube. In this case, the drug to be injected or the product resulting from the reaction easily flows back to the hopper side of the extruder. In the case of obtaining a polymer from the polymer, the polymer also flows back at the same time as the backflow of the drug, so that the polymer backflowed to the hopper side in the extruder is returned to the reaction tube side by the extruder, thereby preventing the backflow of the drug on the downstream side of the extruder. However, if the product is a gaseous or liquid substance at room temperature, the viscosity is low, so once it flows back, it is difficult to return to the reaction tube side, and as a result, the drug or product continues to flow back normally. do.

If this state continues further, as a result of the cylinder wall surface being wetted by the drug or the product, the raw material cannot be supplied, and as a result, the material cannot be sent to the reaction tube.

That is, when using an extruder for monomerization of a polymer, the point which is not a big problem in patent document 4 becomes important as a 1st subject mentioned above.

In addition, at the time of starting the apparatus, the raw materials introduced into the extruder are first discharged in a state where no chemical is supplied, and a product having insufficient reaction is discharged. In addition, when the device is stopped, in order to prevent backflow of the raw material to the hopper side due to the breakage of the seal, after supply of the chemical is stopped, the material in the reaction tube is continuously supplied by supplying a material for replacing the reaction tube such as the raw material or the thermoplastic polymer. The device needs to be stopped after draining. Therefore, even when the device is stopped, substances other than the product intended for the replacement of the raw material or the drug are discharged from the outlet of the reaction tube.

In the apparatus which obtains a monomer, since the monomer discharged | emitted from a reaction tube becomes a gas, the product collection | recovery apparatus needs to be sealed. Therefore, it is difficult to remove other than the substance for the above object during continuous operation. It was also difficult to sample the product during operation for inspection for the same reason.

Therefore, as a 2nd subject, the method of taking out the product discharged in a sealed container continuously in arbitrary time slots is mentioned. Moreover, since the property of the substance discharged | emitted in the sealed product recovery container changes as mentioned above, it turned out that the pressure in a product recovery container changes, and the study for safe operation is needed.

Although the method which can produce | generate a monomer continuously using an extruder is proposed from such a subject, recycling is difficult and most of it is currently buried. However, there is a problem of landfill costs and landfill capacity, and waste reduction is an essential task.

Accordingly, an object of the present invention is to solve the above problems and to provide a foaming urethane treatment method capable of precisely injecting a chemical agent when the foamed urethane is reacted with a chemical agent at a high temperature and high pressure, and to provide a method for treating the foamed urethane. Is in.

In order to achieve the above object, the invention according to claim 1 is introduced into the extruder for supply, pressurized while extruding the foamed urethane with a screw in the supply extruder, while heating the urethane and connected to the supply extruder Inject | pouring a chemical | medical agent into the urethane foam of high temperature and high pressure from a chemical | medical agent injection apparatus, and then distributing it to the reaction tube from the said extruder for supplying, and monomerizing foamed urethane using the high temperature high pressure field, based on the torque value given to the screw. It is a processing method of urethane foam characterized by controlling the said chemical | medical agent injecting apparatus.

In the invention of claim 2, before disintegrating the foamed urethane, the foamed urethane is introduced into the extruder for supply in advance, and the torque value of the screw at the time of reaching the drug injection portion of the drug injection device connected to the supply extruder. It is a processing method of the foaming urethane of Claim 1 which injects the chemical | medical agent heated beforehand by measuring more than, and after becoming the above-mentioned torque value at the time of monomerizing foamed urethane, and inject | pouring the said chemical | medical agent injection apparatus.

The invention of claim 3 is a monomer obtained by decomposing the monomer of the foamed urethane monomerized in the reaction tube through a pressure regulating device, and then introduced into a product recovery vessel and adjusting the pressure by the product recovery vessel. It is a processing method of the expanded urethane of Claim 1 or 2 which collect | recovers.

According to a fourth aspect of the present invention, in the product recovery container, a movable undecomposed product recovery container is provided, and the product introduced into the product recovery container from the pressure adjusting device is selectively recovered by a movable undecomposed product recovery container. And the processing method of the expanded urethane of Claim 3 which collects the product which does not fully react.

According to the invention of claim 5, a sampling mechanism is provided in a pipe for discharging the product from the pressure adjusting device to the product recovery container, and the foaming according to claim 3 which collects the product discharged from the pressure adjusting device by the sampling mechanism. It is a processing method of urethane.

The invention of claim 6 is a method for treating the urethane foam according to claim 1, wherein the drug is a polyol having two or more diols or hydroxyl groups, and the monomer obtained as the product is a polyol having two or more hydroxyl groups.

According to the invention of claim 7, the foamed urethane is introduced into a supply extruder, the foamed urethane is extruded while the foamed urethane is extruded with a screw in the supply extruder, the foamed urethane is heated, and the drug is injected from the chemical injection device connected to the supply extruder. In the urethane foam processing apparatus which injects into the urethane of high temperature and high pressure, and distributes it to the reaction tube from the said extruder for supply, and monomerizes urethane of urethane using a high temperature high pressure field, the torque sensor is provided to the motor which drives the said screw. Is installed, and the drug injection device is controlled based on the torque value of the torque sensor.

According to the invention of claim 8, a pressure regulating device is connected to an outlet of the reaction tube, and a product recovery container for cooling and recovering a product is connected to the pressure adjusting device, and a product that is not sufficiently reacted in the product recovery container. It is a processing apparatus of the foamed urethane of Claim 7 with which the movable undecomposed-product collection container which collect | collects is provided.

Invention of Claim 9 is the processing apparatus of foamed urethane of Claim 7 with which the sampling mechanism which collect | collects the product discharged from the said pressure regulator is provided in the piping which discharges a product from the said pressure regulator to the said product collection container.

According to the present invention, when the waste of the foamed polyurethane used in home appliances, automobiles, buildings, etc. is continuously chemically treated in a high temperature and high pressure atmosphere using a supply extruder, the drug injection is precisely performed to thereby reverse the flow of the drug. It has an excellent effect of being able to prevent continuous processing.

1 is a diagram showing an embodiment of the present invention.
It is a figure which shows the detail of the product recovery container shown in FIG.
3 is a diagram showing a measurement result of molecular weight distribution of a product obtained in the example of the present invention.
It is a figure explaining the timing to inject | pour a chemical | medical agent in this invention.

EMBODIMENT OF THE INVENTION Hereinafter, one preferred embodiment of this invention is described in detail based on an accompanying drawing.

First, a foaming urethane treatment apparatus is demonstrated according to FIG.

In FIG. 1, 10 is a foamed urethane supply feeder, the supplying extruder 11 is connected to the foamed urethane supply feeder 10, and the reaction tube 12 is connected to the discharge port 11d of the supplying extruder 11. In FIG. ) Is connected, and the product recovery container 14 is connected to the reaction tube 12 via a pressure adjusting device 13 made of a valve, a gear pump, or the like.

Foamed urethane P injected into the foamed urethane supply feeder 10 is foamed polyurethane as waste used for thermal insulation, such as home appliances, automobiles, buildings, etc., and is composed of one that is crushed and pressurized at room temperature.

For the foamed urethane feeder 10, it is necessary to use a screw feeder, a table feeder, a circle feeder, or the like, and it is necessary to select a feed amount stable. More preferred is a loss-in-weight method in which the feed rate is measured to automatically adjust the feed rate.

The supply extruder 11 is formed by providing the single screw 11s in the cylinder 11c as shown in the figure. In addition to the single screw extruder, it is commercially available, including a twin screw extruder having two screws, but in the present invention, a single screw extruder is simple and inexpensive. The method of pressurizing urethane effectively by using a single screw extruder was the same as the method of Japanese Patent Application No. 2010-104900.

As a supply extruder 11, even when a single screw extruder is used, a feed feeder 10 made of an extruder is used for supplying a polyurethane to the single screw extruder, and the supply reaches the junction between the hopper 11h and the supply extruder 11. It is preferable to supply material on condition that the area which occupies 50% or more of the opening part 11a provided in the cylinder 11c of the extruder 11 is not covered by the raw material to supply. When the material to be supplied is small, the material supplied to the opening 11a is immediately sent to the discharge direction of the cylinder 11c, so that the opening 11a is not covered by the raw material. When the supply amount is increased, the discharge side of the opening 11a is covered with the raw material. When the supply amount is further increased, the raw material gradually spreads through the entire opening 11a. The ease of bridge becomes easier to bridge as the frictional resistance between the wall surface of the opening 11a and the raw material increases with respect to the weight of the raw material accumulated in the opening 11a. Therefore, it is preferable that the opening 11a is completely blocked with a raw material and operated while maintaining the state where the contact surface between the wall surface of the opening 11a and the raw material is not wide.

As the extruder 11 for supply, when extruding a polymer with a single screw extruder, a material can be supplied generally, without a feeder. However, especially in the case of supplying a pulverized product having a specific gravity, which has a specific gravity, which is foamed, and which is easy to bridge, the opening 11a of the cylinder 11c is not completely filled with raw materials as described above. It is valid to control without.

It is near the discharge port 11d of this supply extruder 11, ie, it is an upstream side of the discharge port 11d, and it is pressurized with foam urethane P, and the inside of the supply extruder 11 is supplied with the seal zone Zc as a raw material. On the downstream side of this formation, a drug injection unit 15 for injecting a drug such as diol is formed, and a drug injection device 16 for heating and supplying a drug is connected to the drug injection unit 15. The chemical | medical agent injection apparatus 16 is connected to the chemical | medical agent tank 17, the chemical | medical agent tank 17, and the chemical | medical agent injection part 15, and the chemical | medical agent piping 18 connected to the chemical | medical agent piping 18, and pressurizes and supplies a chemical | medical agent. The chemical | medical agent pump 19 and the heater 21 which heat the chemical | medical agent in the chemical | medical agent piping 18 are made.

Although diol (glycol) used as a chemical | medical agent is considered to be the most effective using ethylene glycol and diethylene glycol, It is not limited to this. It is also possible to use polyhydric alcohols, including for example diols. For example, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, 1,3-butanediol, propylene glycol, polypropylene glycol, pentanediol, polyethylene glycol, pentaerythritol, sorbitol, methylcarbitol, triethylene glycol, ethyl Polyfunctional alcohols, such as carbitol, tetraethylene glycol, and butyl carbitol, can also be used individually or in mixture of 2 or more types.

If the drug is supplied to the extruder at room temperature without heating, and then heated from the outside of the reaction tube, a product can be obtained but a temperature distribution inside the reaction tube occurs. That is, when the drug is supplied to the extruder at room temperature, the material is heated in the extruder or the reaction tube. At this time, since the heating from the wall surface of the extruder or the reaction tube tends to occur a temperature distribution, as a result there is a problem that the reaction product is not uniform. For this reason, since a problem arises that an unreacted solid content is contained in the product, it is preferable to heat the drug in advance. By injecting a previously heated drug, the diffusion can be promoted and the temperature can be made uniform.

The screw 11s of the supply extruder 11 is driven by the motor 20. The torque sensor 22 is provided in the motor 20, and the chemical | medical agent pump 19 of the chemical | medical agent injection apparatus 16 is controlled by the detection value of the torque sensor 22. As shown in FIG.

The molecular chain skeleton of the polyurethane shows the movement of the main chain at 150 ° C to 250 ° C. By setting it as 150 degreeC or more, it is possible to compress a polyurethane in an extruder. On the other hand, if the temperature is higher than 250 ° C., urethane may slip on the surface of the cylinder so that the material cannot be sent forward with a strong force, and as a result, there is a problem that it cannot be compressed.

Therefore, in the apparatus configuration from the extruder 11 for supply to the reaction tube 12, the temperature of the supply zone Za and the pressurized zone Zb is 100 degreeC-150 degreeC, and 150 degreeC-250 degreeC, respectively. By maintaining the temperature and pressure of the reaction zone Zd in the reaction tube 12 at 200 ° C. to 300 ° C., the pressure of 0.5 MPa to 10 MPa, and the reaction time of 5 to 30 minutes, supply, pressurization, and decomposition reaction are possible. . That is, it is necessary to have three or more independent temperature control zones Za, Zb, Zd.

Here, it is preferable to make reaction temperature in the reaction tube 12 into 200 to 300 degreeC. When the reaction temperature is lower than 200 ° C., the decomposition of the product is slow and the target polyol is obtained. However, since the reaction does not proceed sufficiently, the components of the remaining solid content are mixed so that the reaction temperature is preferably 200 ° C. or higher. When the reaction temperature is higher than 300 ° C, decomposition of the product proceeds excessively, amine is generated and strong odor is generated. Therefore, the reaction temperature is preferably 300 ° C or lower.

The feed extruder 11 and the reaction tube 12 need to be a pressure resistant designed container.

Here, the temperature of the discharge port 11d of the supply extruder 11 is equal to or higher than the softening point temperature of the raw material (foam urethane), the softening point is + 100 ° C. or lower, and the temperature of the extruder discharge port is A (° C.) and the injection temperature of the chemical agent. When B (° C.), the reaction temperature is C (° C.), the discharge amount of the raw material is Wa (g / min), and the injection amount of the drug is Wb (g / min), the specific heat before 1 is mixed before the drug mixture. The temperature A 'and the temperature C' after mixing have the following relationship.

C '(Wa + Wb) = AWa + BWb

C '= (AWa + BWb) / (Wa + Wb) (One)

It is preferable that C 'temperature exists in the range of C-50 <C' <C + 50 with respect to reaction temperature C made into the objective. Substituting this formula into C-50 <C '<C + 50,

C-50 <(AWa + BWb) / (Wa + Wb) <C + 50

(C-50) (Wa + Wb) <AWa + BWb <(C + 50) (Wa + Wb). (2)

From (C-50) (Wa + Wb) <AWa + BWb of the formula,

(C-50) (Wa + Wb) -AWa <BWb

[(C-50) (Wa + Wb) -AWa] / Wb <B... (3)

(2) AWa + BWb <(C + 50) (Wa + Wb)

BWb <(C + 50) (Wa + Wb) -AWa

B <[(C + 50) (Wa + Wb) -AWa] / Wb... (4)

In order to control in the range of C-50 <C '<C + 50 with respect to reaction temperature C aimed at the temperature of C' from Formula (3) and (4), the injection temperature B of a chemical | medical agent is the following conditions.

[(C-50) (Wa + Wb) -AWa] / Wb <B <[(C + 50) (Wa + Wb) -AWa] / Wb

You just need to satisfy.

More precisely, it is better to use the value considering the heat capacity of each material instead of Wa and Wb. In other words,

Wa '= Wa? Ca

Wb '= Wb? Cb

It is more preferable to use (heat capacity of each material A and B as Ca and Cb) instead of Wa and Wb.

The product recovery container 14 includes a jacket 24 that is cooled with a refrigerant around its outer periphery so as to cool down the monomer decomposed by the reaction of the urethane foam with the urethane in a high temperature and high pressure in the reaction tube 12. The filter 25 which catches solid content (impurity) S and filters a monomer is provided, and the discharge valve 26 is provided in the lower part. Moreover, the trapper 28 is connected to the product recovery container 14 via the back pressure valve 27, and the tank 30 is connected through the heat exchanger 29, and the exhaust pipe 31 is connected to the tank 30. ) Is connected. The back pressure valve 27 keeps the pressure in the product recovery container 14 constant, and exhausts the gas to the trapper 28 when the pressure is higher than or equal to the constant pressure. The trapper 28 removes solids and the like in the gas and flows the gas to the heat exchanger 29. In the heat exchanger 29, the gas is cooled to liquefy the condensable gas and send it to the tank 30. In the tank 30, liquid content is collect | recovered and non-condensable gas is exhausted from the exhaust pipe 31. FIG. Moreover, the safety valve 32 which discharges gas when the pressure in the product recovery container 14 raises abnormally is connected to the product recovery container 14.

And the sampling mechanism 34 is provided in the piping 33 which connects the pressure regulator 13 connected to the reaction tube 12, and the product recovery container 14, and in the product recovery container 14, A movable undecomposed product recovery vessel 40 is installed. By attaching either or both of these facilities, these can remove from the product recovery container 14 other than the target substance produced | generated at the time of the start of operation | operation of a device, or a stop.

The sampling mechanism 34 is installed in the folder 35 connected to the pipe 33, the ball valve 36 provided in the folder 35, and the folder 35 so as to move freely, and the tip is divided in half. Sealing between the sampling tube 37, the folder 35 and the sampling tube 37, and for opening the rear end 35a of the folder 35 to take out the product sampled from the sampling tube 37 after sampling. It consists of a folder fixing and a shaft seal joint 38. The folder fixing and shaft sealing joint 38 is composed of a screw type or the like for tightening and fixing the rear end portion 35a to the folder base 35b connected to the pipe 33.

This sampling mechanism 34 inserts the tip divided | segmented into half of the sampling tube 37 into the flow path of the piping 33 through the ball valve 36, and directly collects the product which flows out from the piping 33. I collect it. At this time, the folder 35 maintains the pressure so that internal pressure rises when the sampling tube 37 is inserted, and this sampling tube 37 does not protrude, and after sampling, the sampling tube 37 is provided with a ball valve ( After moving backward from 36, the ball valve 36 is closed, and then, the product other than the purpose collected from the sampling tube 37 by opening the rear end 35a with the folder fixing and shaft seal joint 38, or The product sample can be taken out.

The movable undecomposed product recovery vessel 40 is mounted to the top plate of the product recovery vessel 14 with an arm 41 bent by an L-shape, and the arm 41 is attached to the top plate by a sealing device such as an O-ring ( 42) rotatably mounted without impairing the sealability.

Next, the foamed urethane treatment method using the foamed urethane treatment apparatus shown in FIG. 1, FIG. 2 is demonstrated.

As described above, the urethane foam P is supplied from the feed feeder 10 to the supply extruder 11, and is extruded while being heated from the supply zone Za to the pressurized zone Zb by the rotation of the screws 11s. . Here, the temperature in supply zone Za is 100 degreeC-150 degreeC, and the temperature in pressurization zone Zb becomes 150 degreeC-250 degreeC, and it is a seal zone by foam urethane on the downstream side of pressurization zone Zb. (Zc) is formed, drugs such as diol are injected from the drug injection unit 15 on the downstream side of the seal zone Zc by the drug injection device 16, and the reaction tube is discharged from the discharge port 11d together with the urethane foam. Circulated in 12.

In the reaction zone Zd in the reaction tube 12, the temperature is maintained at 200 ° C. to 300 ° C., the pressure is 0.5 MPa to 10 MPa, and the reaction time (residency time) is 5 to 30 minutes. Is produced and is recovered from the pressure regulating device 13 through the pipe 33 to the product recovery container 14.

At this time, a thermometer (not shown) is provided on the pipe wall of the most downstream part (extruder side) of the chemical | medical agent piping 18 in which the heater 21 of the chemical | medical agent injection apparatus 16 was installed, and the supplying extruder 11 of the The temperature of the cylinder 11c is measured. Moreover, it is in the said range by providing the sensor which measures the internal temperature of the cylinder 11c in the vicinity of the discharge port 11d of the supply extruder 11, and confirming that the mixture becomes the temperature near the target reaction temperature C. The temperature adjustment of the temperature A of the discharge port and the injection temperature B of the medicine is controlled.

In general, when the polymer is processed by an extruder, it is melt-molded at a softening point or a melting point of + 50 ° C to + 100 ° C. It is preferable that the temperature (temperature A of a discharge port) of foamed urethane conforms to this empirical setting range.

When foaming urethane is extruded by the rotation of the screw 11s and monomerized in the reaction tube 12 by the supply extruder 11, the monomer as a product may become a liquid at normal temperature, and in some cases it may become a gas. In the reaction tube 12, the gas becomes substantially gas. In this case, even if the chemical | medical agent is inject | poured from the chemical | medical agent injection part 15, if the seal zone Zc is not formed reliably, it will become difficult for a chemical | medical agent to flow back the supply extruder 11 and to extrude foam urethane.

Therefore, in the present invention, when extruding the urethane foam by the supply extruder 11, only the urethane foam is extruded in advance, and the torque value when the urethane foam reaches the chemical | medical agent injection part 15 is made into the torque sensor 22. FIG. After the start of supply of the material at the time of reaction extrusion, the torque rises, and when the pressure is equal to or more than the specific torque measured when only the polyurethane is extruded as described above, the medicine is injected from the drug injection unit 15. It is to prevent the backflow of the drug.

When this is demonstrated according to FIG. 4, first, at the time of extrusion start, as shown to FIG. 4 (a), the urethane foam from the hopper 11h is taken in in the supply extruder 11, and rotation of the screw 11s is performed. To be supplied to the supply zone Za, extruded while being heated and melted in the supply zone Za, and as shown in FIG. 4 (b), the urethane foam is pressed while being heated to a high temperature in the pressurized zone Zb, Thereafter, as illustrated in FIG. 4C, the seal zone Zc is formed of molten expanded urethane. At this time, when the supply amount of urethane foam is constant, the torque applied to the screw 11s rises while the urethane foam is extruded from the supply zone Za to the pressurized zone Zb, and when the seal zone Zc is formed approximately It is a constant value.

However, in the initial stage of extrusion, since the urethane foam is not filled in the reaction tube 12, the urethane foam is filled in the reaction tube 12, and then the chemical injection part 15 is opened, and the urethane foam When the torque value at the time of flowing into the injection part 15 is calculated | required, it turns out that the seal zone Zc was formed from this torque value, and backflow can be prevented by inject | pouring a chemical | medical agent at that time.

Moreover, when the quantity of the urethane foam injected into the supply extruder 11 is fluctuate | varied and the torque applied to the screw 11s becomes less than a preset value, backflow can be prevented by stopping injection of a chemical | medical agent.

Moreover, as shown in the subject, since the product with insufficient reaction is discharged from the reaction tube 12 at the time of start-up, the pressure rises first, and after that, the sufficiently reacted product is discharged. To reach. Since the target product is produced from this point, until then, the movable undecomposed product recovery vessel 40 is placed directly under the pipe 33 by the arm 41 to recover a product having insufficient reaction. And mixing of unreacted products can be prevented. After the sufficiently reacted product is discharged, the movable undecomposed product recovery vessel 40 is moved to collect the desired product in the product recovery vessel 14.

At this time, the sampling mechanism 34 can accurately confirm whether the product is unreacted or sufficiently reacted by directly sampling the product.

Here, the monomerization of this invention means returning to the chemical raw material of polyurethane. As a raw material of polyurethane, a waxy thing and an oligomer may be used, and monomerization here does not necessarily return to the monomer which shows the repeating minimum unit of a polymer, but includes obtaining a wax and an oligomer.

The monomer discharged in the product recovery container 14 is cooled by the jacket 24 and liquefied, it is kept warm, it passes through the filter 25, and it is discharged | emitted from the discharge valve 26 to the conditions suitable for the next process.

In this way, the conditions inside the reaction tube 12 are not stabilized at the time of starting and stopping the operation of the processing apparatus, and the product which is not completely decomposed is discharged, and completely without sacrificing the sealability of the product recovery container 14. By providing a movable undecomposed product recovery vessel 40 which can be operated in the product recovery vessel 14 to remove the product which has not been decomposed, it is possible to obtain a monomer in which the reaction is sufficiently performed.

In addition, the sampling mechanism 34 and the movable undecomposed product recovery container 40 are controlled based on the measured values obtained by a pressure measuring device (not shown) for measuring the internal pressure of the reaction tube 12. Especially in the case of waste treatment, there is a variation in the properties of the feed, so it is necessary to check the state of the product during operation. Therefore, the method of taking out a sample from the sealed product recovery container 14, maintaining the sealed state is effective.

Example

Next, an Example and a comparative example are demonstrated.

(Example 1)

The urethane foam was processed with the processing apparatus shown in FIG.

Foamed urethane is not completely melted since polyurethane having a crosslinked structure is used. However, it is possible to pressurize and extrude by the propulsion force of the screw 11s. The extruder 11 for supply used the cylinder diameter 20mm and the extruder of L / D = 25, and the cylinder temperature of supply zone Za and pressurization zone Zb was 160 degreeC and 170 degreeC, respectively.

Foamed urethane used as a raw material is foamed urethane which is used for thermal insulation, and is pulverized and pressurized and compressed at normal temperature. Specific gravity is about 0.1. Since it is not solidified, it collapses easily into a powdery form. The sieve was filtered through a 5 mm mesh and foamed urethane was used. When using a larger extruder by scale-up, it is possible to enlarge a grinding | pulverization size. In addition, the rotation speed of the screw 11s was 60 rpm, and the experiment was performed.

Supply of the urethane foam P to the hopper 11h of the supply extruder 11 used the feeder 10, and quantitatively supplied the urethane foam P to the hopper part. In addition, the agitator was attached to the feeder 10 and stirred to prevent the powder of polyurethane from being bridged and the supply to the supply extruder 11 from becoming unstable. In addition, the quantity of polyurethane supplied from the feeder 10 was supplied in the range which does not completely cover the surface of the screw 11s which rotates in the hopper in the supply part of the supply extruder 11. Here, 2 g / min of polyurethane was fed to the hopper.

At this time, only the polyurethane is extruded in advance in the state in which the hole of the drug injection unit 15 is opened, and when the polyurethane is discharged from the hole after starting extrusion, that is, when the polyurethane has reached the drug injection unit 15 Was found to be 2.0 N? M.

Therefore, the torque sensor 22 monitors the torque at the time of supply of the material at the time of reaction extrusion, and after starting the supply, the torque rises and the torque value becomes 2.0 NNm or more, and then from the medicine injection portion 15 The medication pump 19 was controlled to start injecting the medication.

Thereby, when the torque value became 2.0 N * m or more, the seal zone Zc was formed and it was confirmed that backflow of a chemical | medical agent does not generate | occur | produce, even if it inject | pours a chemical | medical agent.

In the chemical | medical agent injecting part 15, the check valve (not shown) which moves the beads inside was used for the nozzle to inject. This is to prevent polyurethane from flowing back and being blocked by the chemical | medical agent piping 18 of a chemical | medical agent (diethylene glycol). In addition, since the stroke of the ball moving as a valve of a check valve was quick, reaction could prevent backflow, so it was 1 mm in this experiment. In addition, the shorter the distance from the bead to the inner surface of the cylinder 11c of the feed extruder 11, the faster the reaction of the check valve. If the check valve moves badly, the drug may leak even in a stage where the torque is not sufficiently raised, and in that case, the material may slip and the raw material may not be supplied. By designing the position of the beads as close to the inner surface of the cylinder 11c as possible, the structure of the check valve can be made sensitive and the structure difficult to flow back. In addition, at the start of injection, the pressure regulating device 13 was closed and operated so that the injected liquid or gas might not be vaporized.

Next, the internal temperature of the reaction tube 12 was 260 degreeC. The volume of the reaction tube 12 was 100 ml. In other words, when the specific gravity of the polyurethane and diethylene glycol mixture was assumed to be 1.0, the residence time under the reaction conditions was about 20 to 30 minutes. Further downstream of this, a valve was provided as the pressure regulating device 13. The outlet temperature of the valve was 240 degreeC.

This is to prevent phase flow from occurring in the valve and the flow cannot be controlled by lowering the boiling point of the diethylene glycol used for decomposition. By opening and closing this valve, the internal pressure of the reaction tube 12 was controlled in the range of 1-3 MPa.

In addition, the refrigerant is allowed to flow into the jacket 24 of the product recovery container 14 connected to the pressure regulating device 13 through the pipe 33 to cool the inside of the product recovery container 14 to generate steam of the product. Not to. In this case, a 0 ° C. refrigerant was used. In addition, the safety valve 32 prevented the product recovery container 14 from being pressurized to 1 MPa or more.

In particular, the safety valve 32 discharges the combustible gas and increases the pressure in the product recovery container 14, so that there is a risk of explosion, so that the pressure can be maintained at a pressure lower than the internal pressure of the product recovery container 14.

Further, by installing a back pressure valve 27 operating at a lower pressure than the safety valve 32 and connecting the trapper 28 and the heat exchanger 29 downstream thereof, the product recovery container 14 cannot be completely cooled. The solvent was allowed to recover.

Moreover, the product which does not fully progress reaction at the time of start-up is collect | recovered by the movable undissolved product recovery container 40 which makes it move in the direction shown by the arrow of FIG. 2 in the product recovery container 14, and also the sampling mechanism 34 is carried out. Product samples were taken with.

The operation of the movable undecomposed product recovery vessel 40 and the sampling mechanism 34 was performed by monitoring the pressure with a pressure measuring device (not shown) for measuring the internal pressure of the reaction tube 12.

That is, at the time of starting, while filling up material progresses, a pressure rises. Thereafter, the chemical reaction proceeds and the viscosity of the material decreases, and as a result, the pressure decreases and reaches a constant value. By collecting the product other than the object discharged to the time point at which the pressure reaches a fixed amount by the sampling mechanism 34 or the movable undecomposed product recovery container 40, the overflow discharged in an unstable operation state was separated. At this time, the sampling mechanism 34 or the movable undecomposed product recovery container 40 was controlled from the measured value obtained by the pressure measuring device.

After the pressure in the reaction tube 12 becomes constant, recovery in the movable undecomposed product recovery vessel 40 is stopped, the product is introduced into the product recovery vessel 14, and the filter 25 is used to collect solids from the product. Impurity (S) was removed. In addition, when performing filtration by the filter 25, the temperature of the product in the product recovery container 14 was heated to 70 degreeC or more.

The molecular weight distribution of the product of this invention obtained using this apparatus is shown in FIG.

In addition, as a comparison, a recycled polyol and a batch treatment obtained by injecting a polyurethane: diethylene glycol = 1: 1 into a autoclave and performing a treatment for 10 minutes in a saturated vapor pressure of diethylene glycol at 260 ° C. It turned out that it has the same molecular weight distribution. It was found that the foam obtained by producing a foamed polyurethane using 10% of a batch-treated recycled polyol added to a virgin polyol exhibited properties equivalent to those of virgin materials with respect to thermal conductivity, compression, and bending mechanical properties.

That is, it turned out that this invention is applicable as an apparatus which continuously recycles a polymer with the chemical | medical agent of high temperature and high pressure.

(Example 2)

When the polyurethane powder is very brittle and covers 50% or more of the opening 11a of the supply extruder 11 that contacts the hopper, the supply of the polyurethane powder to the supply extruder 11 is not stable. As a result of the variation in the amount of resin extruded by the supply extruder 11, a deviation occurs in the residence time, and the characteristics of the product are disturbed, or in some cases, the supply of materials is insufficient and the seal is incomplete. There is a possibility that the product flows back into the hopper. The rotation speed of the screw 11s at this time was 50 rpm.

In addition, the screw shape of the supply extruder 11 used at this time is the part which has R and a taper part whose cross-sectional area is 4 in the relationship between the flow path cross-sectional area R and L / D which is a ratio of the length and diameter of the cylinder of an extruder. The L / D of 10 was used. At this time, the chemical | medical agent injected in the downstream side was sealed by compressing a raw material by narrowing the flow path cross section area of the discharge side of a screw.

Since the stability of the pressure at the time of compression changes large by the influence of the temperature of this taper part, the range of 130 degreeC-250 degreeC is preferable. Here, the cylinder temperature of the extruder in the taper part and the chemical | medical agent injection part of the extruder exit was 170 degreeC. In addition, when the torque value detected by the torque sensor 22 becomes more than a fixed value (2.0 N? M or more), the preheated to 300 ° C from the tip of the screw to the hopper side of L / D = 1.5 in advance. 2 g / min of ethylene glycol was injected. It was confirmed that the drug did not flow back by this injection, and it was confirmed that the reaction was sufficiently performed in the reaction tube 12 as in Example 1.

(Comparative Example 1)

Treatment was carried out using the same apparatus and method as in Example 1, but in the case of Comparative Example 1, the injection of the material was started from the drug injection unit at the time when the supply of the material was started and the torque value increased to 0.5 N 이 m. Started. As a result, the drug flowed back toward the hopper 11h and the material slipped, and the material could not be pushed into the reaction tube when the pressure reached 0.5 MPa or more.

Therefore, before injecting the medicine, the torque value when the polyurethane has reached the medicine injecting portion 15 beforehand is obtained in a state where the hole of the chemical injecting portion is opened. As a result, the torque value is 0.5N. Since the medicine was injected at the time of? m, it was found that reflux occurred.

Although the Example and the comparative example were demonstrated above, this invention is not limited to an Example, For example, although the Example uses the extruder whose cylinder diameter is 20 mm, in order to ensure sufficient throughput, it is a commercial utility apparatus. In the case of a large extruder of about 150 mm, it is necessary to carry out the operation conditions of about 100 revolutions or less. In this case, although there are some fluctuations in the torque value, backflow can be prevented by injecting a chemical agent when the torque value becomes 2.0 NNm or more.

11 Feeding extruder
11s screw
12 reaction tubes
16 pharmaceutical injection device

Claims (9)

The urethane foam is introduced into the supplying extruder, the foaming urethane is pressed while the foamed urethane is extruded with the screw in the supplying extruder, and the urethane foam is heated. Injecting and then circulating from the supplying extruder to the reaction tube to monomerize the urethane foam using a high-temperature high-pressure field, foaming characterized in that the drug injection device is controlled based on the torque value given to the screw Method of processing urethane. The method of claim 1,
Before decomposing the urethane foam, the urethane foam is put into the extruder for supply in advance, and the torque value of the screw at the time of reaching the chemical | medical agent injection part of the said chemical injection device connected to the said feed extruder is measured, and foaming The method of processing urethane which inject | pours the chemical | medical agent heated beforehand from the said chemical | medical agent injecting apparatus, after becoming urethane or more at the time of monomer measurement of urethane. The method according to claim 1 or 2,
After reducing the pressure of the foamed urethane monomer monomerized in the said reaction tube through a pressure adjusting device, it introduce | transduced into a product recovery container, and the foamed urethane which collect | recovers the decomposed monomer, adjusting the pressure with the product recovery container, Treatment method. The method of claim 3,
In the product recovery container, a movable undecomposed product recovery container is provided, and the product introduced into the product recovery container from the pressure regulating device is selectively recovered to the movable undecomposed product recovery container and is not sufficiently reacted. Process for the treatment of foamed urethane to collect the product. The method of claim 3,
The piping for discharging a product from the said pressure regulator to the said product collection | recovery container is provided with the sampling mechanism, The sampling mechanism of the foamed urethane which collects the product discharged from the said pressure regulator by the sampling mechanism. The method of claim 1,
The method for treating expanded urethane wherein the drug is a polyol having two or more diols or hydroxyl groups, and the monomer obtained as a product is a polyol having two or more hydroxyl groups. The urethane foam is introduced into the supplying extruder, the foaming urethane is pressed while the foamed urethane is extruded with the screw in the supplying extruder, and the urethane foam is heated. In the foaming urethane processing apparatus which injects and distributes a foamed urethane to a reaction tube from the said supply extruder to a reaction tube after that, using a high temperature high pressure field, the torque sensor is provided in the motor which drives the said screw, and the torque The processing apparatus of the urethane foam, characterized in that for controlling the drug injection device based on the torque value of the sensor. The method of claim 7, wherein
A pressure regulator is connected to the outlet of the reaction tube, and a product recovery vessel for cooling and recovering a product is connected to the pressure regulator, and a movable fine powder for collecting a product not sufficiently reacted in the product recovery vessel. The processing apparatus of foamed urethane with which a sea product recovery container is provided. The method of claim 7, wherein
The processing apparatus of the urethane foam provided with the sampling mechanism which collect | collects the product discharged | emitted from the said pressure regulator in the piping which discharges a product from the said pressure regulator to the said product collection container.

Images