CN110776633A - A kind of nylon 6 polymerization test device - Google Patents

Abstract

The invention discloses a nylon 6 polymerization test device, comprising an intermediate storage tank, an additive preparation tank, a dynamic mixer, a prepolymerizer, a postpolymerizer, a pelletizer, a twin-screw extruder, a pre-extraction tank, an extraction tower, Wet chipping silo, drying drum, mixing drum, heat seal packaging machine, the intermediate storage tank is connected to the dynamic mixer, the additive formulation tank is connected to the dynamic mixer, and the dynamic mixer is connected to the prepolymerizer , the front polymerizer is connected to the rear polymerizer, the rear polymerizer can be connected to the pelletizer, the rear polymerizer can also be connected to a twin-screw extruder, and the twin-screw extruder is connected to the pelletizer , the pelletizer is connected to the pre-extraction tank, the pre-extraction tank is connected to the extraction tower, and the extraction tower is connected to the wet slice silo. Today, industrial production cannot be used for new product development and multi-variety and multi-addition. In addition, the cost of research and development is huge, which is unbearable.

Description

A kind of nylon 6 polymerization test device

technical field

The invention relates to the field of polymerization test devices, in particular to a nylon 6 polymerization test device.

Background technique

At present, the maximum production capacity of a single caprolactam polymerization tube in China has reached 400 tons per day, but the industrial production line of nylon polymerization cannot carry out product testing, mainly because the loss is too large, and it will also consume a large amount of production capacity. If the production capacity is tested, the daily loss of funds is millions of yuan, which is unbearable for the enterprise, and a lot of manpower and material resources are wasted.

If an industrialized production line is used for research and development, the flexibility of research and development will be reduced, some data adjustments cannot be performed, and multiple varieties and multiple additives cannot be tested, which will only delay the research and development of new products.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a polyamide 6 polymerization test device to solve the problems raised in the above background technology.

In order to achieve the above purpose, the present invention provides the following technical solutions: a nylon 6 polymerization test device, including an intermediate storage tank, an additive preparation tank, a dynamic mixer, a prepolymerizer, a postpolymerizer, a pelletizer, and a twin-screw extruder. , pre-extraction tank, extraction tower, wet chip silo, drying drum, mixing drum, heat sealing packaging machine, the intermediate storage tank is connected to the dynamic mixer, the additive preparation tank is connected to the dynamic mixer, The dynamic mixer is connected to a pre-polymerizer, which is connected to a post-polymerizer, which can be connected to a pelletizer, and the post-mixer can also be connected to a twin-screw extruder. The twin-screw extruder is connected to a pelletizer, which is connected to a pre-extraction tank, which is connected to an extraction tower, which is connected to a wet chipping bin, which is connected to To the drying drum, which is connected to the mixing drum.

Wherein, the caprolactam is pumped to the intermediate storage tank from the polymerization workshop, and the caprolactam and various additives are pumped into the dynamic mixer in proportion by a metering pump.

Wherein, the dynamic mixer is fully mixed and then added to the front polymerizer.

Wherein, the temperature in the prepolymerizer is 260-280°C, the pressure is 0.1-0.3MPa, and the biphenyl vapor jacket is 0.05-0.1MPa, and the mixture is subjected to hydrolysis ring-opening and partial polyaddition reaction in the prepolymerizer.

Wherein, the molecular weight of the reaction product is about 8,000-10,000, and the reaction product is transported to the post-polymerizer by a gear pump.

Wherein, the temperature of the middle and upper section of the post-polymerizer is 260-280 °C, the temperature of the lower section is 235-250 °C, the pressure is normal pressure or negative pressure, the upper section of the biphenyl steam jacket is 0.05-0.1MPa, and the lower section of the biphenyl jacket is 0.2-0.6MPa , the reaction product further completes addition polymerization and chain equilibration reaction in the post-polymerizer to generate a polyamide 6 polymer melt with a molecular weight of about 11000-15000.

Wherein, the polymer melt is quantitatively discharged by a gear pump and cast into strips in a casting head.

Among them, the polymer melt is extruded and granulated by a twin-screw extruder, and various modifiers can be added during the process to enhance the flexibility of research and development.

Wherein, the strip is cooled in the quenching tank of the pelletizer, and pelletized to form nylon 6 slices, and the ultra-long slices and powder are separated in a vibrating screen.

Wherein, the slices fall into a pre-extraction tank for pre-extraction, and the slices and water are pumped into the extraction tower with mud.

Wherein, the steam jacket in the extraction tower is 105-115°C, and the pressure is 0.05-0.3MPa.

Wherein, in the extraction tower, the slices are extracted from top to bottom, and the hot desalinated water is countercurrently extracted to the slices from bottom to top, so as to remove the monomers and oligomers contained in the slices.

Wherein, after the extraction water flows out from the top of the tower, it continues to flow to the pre-extraction tank, and the slices are pre-extracted, which saves the cost.

Wherein, because the extraction water contains a certain amount of caprolactam monomer, it is pumped to the concentrated solution recovery system of the polymerization workshop by the extraction water, and after evaporation and concentration, it becomes the recovered caprolactam concentrated solution and reused in the polymerization workshop to save costs.

Wherein, the slices and water are pumped by the slicing cement slurry to the dehydrator located at the upper part of the wet slicing silo for dehydration, and then enter the wet slicing silo for temporary storage.

Wherein, the wet chips are sucked into the drying drum by a vacuum suction system in the wet chip bin for drying, and after drying is completed, they are placed in the mixing drum below for temporary storage and mixing.

Wherein, the mixing drum can store about 3-10 days of slice production.

Wherein, the dry slices are evenly mixed and then weighed and packaged for inspection.

Wherein, a method of using a nylon 6 polymerization test device, comprising the following steps:

S1. First, the raw material liquid caprolactam is pumped from the polymerization workshop to the intermediate storage tank, the additive is added to the additive preparation tank, and the materials in the intermediate storage tank and the additive preparation tank are connected to the dynamic mixer through the plunger pump. After the mixer is fully mixed and uniform, it is added to the front polymerizer for hydrolysis ring-opening and partial addition polymerization. The molecular weight of the reaction product is about 8000-10000. The reaction product is fed into the rear polymerizer through a gear pump to further complete the addition polymerization and The chain equilibrium reaction produces a polyamide 6 polymer melt with a molecular weight of about 11000-15000.

S2. ① The polymer melt is quantitatively discharged through the gear pump, cast into strips in the casting head, and the strips are cooled and pelletized in the quenching tank of the pelletizer to form nylon 6 slices. ② The polymer melt is discharged into the twin-screw extruder, and some modifiers can be added to the twin-screw extruder, and the obtained product is cooled and pelletized in the quenching tank of the pelletizer to form nylon 6 slices .

S3. After the ultra-long slices and powder are separated in the vibrating screen, they fall into the pre-extraction tank for pre-extraction, and then the slices and water are pumped to the extraction tower together with the mud. The desalted water from the bottom-up countercurrent extraction of the slices removes the monomers and oligomers contained in the slices. The extraction water flows out from the top of the tower and continues to flow to the pre-extraction tank, where the slices are pre-extracted.

S4. The chips and water are pumped to the dehydrator located at the upper part of the wet chip bin for dehydration, and then enter the wet chip bin for temporary storage. The wet chips in the wet chip silo are sucked into the drying drum by the vacuum suction system for drying. After drying, they are placed in the mixing drum below for temporary storage. The mixing drum can be stored for about 3 to 10 days for chip production. Quantity, mix evenly and pack for inspection.

The beneficial effects of the present invention are:

The invention is a nylon 6 polymerization test device, the polymerization modification small test platform has a small production capacity, can add various test aids and multi-point addition methods, and has enhanced flexibility, and the daily loss is very low, about 1500 yuan, and the large Significantly reduces R&D costs and reduces production capacity losses. In addition, the technical process of the nylon 6 polymerization test device is highly imitated by the industrialized polymerization production line. If the new product is successfully developed, the technology and process can be directly applied to the industrialized production line.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the device of the present invention;

In Figure 1: 1-intermediate storage tank; 2-additive preparation tank; 3-dynamic mixer; 4-prepolymerizer; 5-postpolymerizer; 6-pelletizer; 7-twin-screw extruder; 8- Pre-extraction tank; 9-extraction tower; 10-wet slice bin; 11-drying drum; 12-mixing drum; 13-heat sealing packaging machine.

Detailed ways

In order to be able to understand the features and technical content of the present invention in more detail, the implementation of the present invention is described in detail below with reference to the accompanying drawings, which are for reference only and are not intended to limit the present invention.

A kind of nylon 6 polymerization test device with reference to Fig. 1, comprises intermediate storage tank 1, additive preparation tank 2, dynamic mixer 3, front polymerizer 4, rear polymerizer 5, pelletizer 6, twin-screw extruder 7, Pre-extraction tank 8, extraction tower 9, wet chip silo 10, drying drum 11, mixing drum 12, heat sealing packaging machine 13, the intermediate storage tank 1 is connected to the dynamic mixer 3, the additive preparation tank 2 is connected to a dynamic mixer 3, which is connected to a front polymerizer 4, which is connected to a rear polymerizer 5, which can be connected to the pelletizer 6, so The post-polymerizer 5 may also be connected to a twin-screw extruder 7, which is connected to a pelletizer 6, which is connected to a pre-extraction tank 8, which is connected to a pre-extraction tank 8. Connected to an extraction tower 9, which is connected to a wet chipping bin 10, which is connected to a drying drum 11, which is connected to a mixing drum 12.

The caprolactam is pumped to the intermediate storage tank 1 from the polymerization workshop, and the caprolactam and various additives are pumped into the dynamic mixer 3 in proportion through a metering pump. After fully mixing in the dynamic mixer 3, it is added to the front polymerizer 4. The hydrolysis ring-opening and partial polyaddition reaction are carried out in the front polymerizer 4, and the reaction product is transported to the rear polymerizer 5 by a gear pump, and the molecular weight is about 8000-10000. The reaction product further completes addition polymerization and chain equilibrium reaction in the post-polymerizer 5 to form a polymer melt with a molecular weight of about 11,000-15,000.

The polymer melt is quantitatively discharged with a gear pump and cast into strips in the casting head. Or extruding and granulating 7 with a twin-screw extruder, during the process, various modifiers can be added. In the quenching tank of the pelletizer 6, it is cooled and pelletized to form nylon 6 slices, and the ultra-long slices and powder are separated in a vibrating sieve.

The slices fall into the pre-extraction tank 8 for pre-extraction, and then the slices and water are pumped to the extraction tower 9 together with the mud. Contains monomers and oligomers. Slices and water are pumped by the slicing cement slurry to the dehydrator located at the upper part of the wet slicing bin 10 for dehydration, and then enter the wet slicing bin 10 for temporary storage. The wet chips are sucked into the drying drum 11 by the vacuum suction system in the wet chip bin 10 for drying. After drying, they are placed in the mixing drum 12 below for temporary storage and mixing. The mixing drum 12 can store about 3 ~10 days of slice production, the final dry slices are evenly mixed and then weighed and packaged for inspection.

Wherein, the temperature in the front polymerizer 4 is 260-280° C., the air pressure is 0.1-0.3 MPa, and the biphenyl vapor jacket is 0.05-0.1 MPa.

Among them, the temperature of the upper section of the post-polymerizer 5 is 260-280 °C, the temperature of the lower section is 235-250 °C, the pressure is normal pressure or negative pressure, the upper section of the biphenyl vapor jacket is 0.05-0.1MPa, and the lower section of the biphenyl jacket is 0.2-0.6 MPa MPa.

Wherein, the steam jacket in the extraction tower 9 is 105-115° C., and the pressure is 0.05-0.3 MPa.

Wherein, after the extraction water flows out from the top of the tower, it continues to flow to the pre-extraction tank 8, and the slices are pre-extracted, which saves the cost.

Wherein, because the extraction water contains a certain amount of caprolactam monomer, it is pumped to the concentrated solution recovery system of the polymerization workshop by the extraction water, and after evaporation and concentration, it becomes the recovered caprolactam concentrated solution and reused in the polymerization workshop to save costs.

Working principle: a method of using a nylon 6 polymerization test device, including the following steps:

S1. First, the raw material liquid caprolactam is pumped to the intermediate storage tank 1 from the polymerization workshop, and the additive is added to the additive preparation tank 2. The materials in the intermediate storage tank and the additive preparation tank are connected to the dynamic mixer 3 through a plunger pump. , after fully mixing in the dynamic mixer 3, it is added to the front polymerizer 4 for hydrolysis ring-opening and partial polyaddition reaction. The molecular weight of the reaction product is about 8000-10000, and the reaction product is added to the rear polymerizer 5 through a gear pump. , and further complete addition polymerization and chain equilibration reaction to generate polyamide 6 polymer melt with a molecular weight of about 11000-15000.

S2. ① The polymer melt is quantitatively discharged through the gear pump, cast into strips in the casting head, and the strips are cooled and pelletized in the quenching tank of the pelletizer 6 to form nylon 6 slices. ② The polymer melt is discharged into the twin-screw extruder 7, and some modifiers can be added to the twin-screw extruder 7, and the obtained product is cooled and pelletized in the quenching tank of the pelletizer 6 to form Nylon 6 slices.

S3, after the ultra-long slices and the powder are divided in the vibrating screen, fall into the pre-extraction tank 8 and carry out pre-extraction, then the slices and water are pumped to the extraction tower 9 with mud, and the slices are top-down in the extraction tower 9. , while the hot desalinated water extracts the slices countercurrently from bottom to top to remove the monomers and oligomers contained in the slices. The extraction water flows out from the top of the tower and continues to flow to the pre-extraction tank 8, where the slices are pre-extracted.

S4, the slices and water are pumped to the dehydrator located at the upper part of the wet slice bin 10 for dehydration, and then enter the wet slice bin 10 for temporary storage. The wet chips in the wet chip bin 10 are sucked into the drying drum 11 by the vacuum suction system for drying. After drying, they are placed in the mixing drum 12 below for temporary storage. The mixing drum 12 can store about 3-10 The production volume of slices per day is evenly mixed and packaged for inspection.

Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, and substitutions can be made in these embodiments without departing from the principle and spirit of the invention and modifications, the scope of the present invention is defined by the appended claims and their equivalents.

Claims (8)

1. A polyamide-6 polymerization test device comprises an intermediate storage tank (1), an additive preparation tank (2), a dynamic mixer (3), a front polymerizer (4), a rear polymerizer (5), a granulator (6), a twin-screw extruder (7), a pre-extraction tank (8), an extraction tower (9), a wet slicing bin (10), a drying drum (11), a mixing drum (12) and a heat sealing packaging machine (13), wherein the intermediate storage tank (1) is connected to the dynamic mixer (3), the additive preparation tank (2) is connected to the dynamic mixer (3), the dynamic mixer (3) is connected to the front polymerizer (4), the front polymerizer (4) is connected to the rear polymerizer (5), the rear polymerizer (5) is connected to the granulator (6), the rear polymerizer (5) is also connected to the twin-screw extruder (7), and the twin-screw extruder (7) is connected to the granulator (6), the granulator (6) is connected to a pre-extraction tank (8), the pre-extraction tank (8) is connected to an extraction tower (9), the extraction tower (9) is connected to a wet chip bin (10), the wet chip bin (10) is connected to a dryer drum (11), and the dryer drum (11) is connected to a mixing drum (12).

2. The polyamide-6 polymerization test device according to claim 1, characterized in that: the materials in the intermediate storage tank and the additive preparation tank are connected with the dynamic mixer through a plunger pump.

3. The polyamide-6 polymerization test device according to claim 1, characterized in that: the temperature in the front polymerizer is 260 ℃ and 280 ℃, the pressure is 0.1-0.3MPa, and the biphenyl steam jacket is 0.05-0.1 MPa.

4. The polyamide-6 polymerization test device according to claim 1, characterized in that: the front polymerizer is connected to the rear polymerizer through a gear pump.

5. The polyamide-6 polymerization test device according to claim 1, characterized in that: the temperature of the upper section of the post polymerizer is 260-280 ℃, the temperature of the lower section of the post polymerizer is 235-250 ℃, the pressure is normal pressure or negative pressure, the biphenyl steam jacket of the upper section is 0.05-0.1MPa, and the biphenyl jacket of the lower section is 0.2-0.6 MPa.

6. The polyamide-6 polymerization test device according to claim 1, characterized in that: the pre-extraction tank is connected with the extraction tower through a slurry pump.

7. The polyamide-6 polymerization test device according to claim 1, characterized in that: the steam jacket in the extraction tower is 105 ℃ and 115 ℃, and the air pressure is 0.05-0.3 MPa.

8. The use method of the polyamide-6 polymerization test device according to claim 1, characterized in that: the method comprises the following steps:

s1, circularly pumping raw material liquid caprolactam into a middle storage tank (1) from a polymerization workshop, adding an additive into an additive preparation tank (2), connecting materials in the middle storage tank and the additive preparation tank to a dynamic mixer (3) through a plunger pump, fully and uniformly mixing in the dynamic mixer (3), adding the materials into a front polymerizer (4) for hydrolysis ring opening and partial addition polymerization, wherein the molecular weight of a reaction product is about 8000-10000, adding the reaction product into a rear polymerizer (5) through a gear pump, and further completing addition polymerization and chain balance reaction to generate a polyamide 6 polymer melt, the molecular weight of which is about 11000-15000;

s2 and S ① are used for discharging the polymer melt quantitatively through a gear pump, casting the polymer melt into strips in a casting head, and cooling and pelletizing the strips in a quenching tank of a pelletizer (6) to form nylon 6 chips;

②, discharging the polymer melt into a double-screw extruder (7), adding some modifier into the double-screw extruder (7), cooling the obtained product in a quenching tank of a granulator (6), and granulating to form polyamide-6 chips;

s3, removing ultra-long slices and powder in a vibrating screen, then falling into a pre-extraction tank (8) for pre-extraction, then pumping the slices and water into an extraction tower (9) by using a slurry pump, wherein the slices are arranged from top to bottom in the extraction tower (9), hot desalted water is used for carrying out countercurrent extraction on the slices from bottom to top to remove monomers and oligomers contained in the slices, and extraction water flows out from the top of the tower and then continuously flows to the pre-extraction tank (8) for carrying out pre-extraction on the slices;

s4, conveying the slices and water to a dehydrator positioned on the upper part of the wet slicing bin (10) through a slurry pump for dehydration, and then entering the wet slicing bin (10) for temporary storage;

wet section in wet section feed bin (10) is dried in vacuum suction system inhales drying drum (11), puts into compounding rotary drum (12) of below after the drying is accomplished and keeps in temporarily, and the slicing output of 3 ~ 10 days can probably be deposited to compounding rotary drum (12), and the packing is waited to examine to the misce bene.

Images