A negative pressure nylon melt spinning pre-treatment equipment

Abstract

The utility model discloses a negative pressure nylon melt spinning pre-treatment equipment, which belongs to nylon spinning production equipment and comprises a shell, wherein two ends of the shell are respectively connected with a feed pipe and a discharge pipe, a rotor is installed in the shell, a negative pressure melt channel is formed between the shell and the rotor, and the melt channel is connected with a gas outlet pipe; the equipment in the present application is arranged after nylon polymerization and before spinning, the original pelletizing, extraction, drying and re-melting processes are cancelled, the melt is directly treated, and the melt after treatment can be spun, the process flow is greatly simplified, and the problem of removing oligomers in nylon through an extraction process in the prior art, which leads to increased production costs and three waste emissions, is solved.

Description

Technical Field

[0001] The utility model relates to nylon spinning production equipment, in particular to negative pressure nylon melt spinning pre-treatment equipment. Background Art

[0002] At present, about 90% of the national nylon production is nylon 6, which is mainly used in the field of civilian fibers. The production process of nylon 6 civilian silk is the hydrolysis polymerization, pelletizing, extraction, drying, cooling, packaging, remelting and spinning of the raw material caprolactam. After polymerization, the high polymer accounts for about 90% of the melt. The extraction process needs to remove about 10% of the monomers and oligomers (extractables) remaining in the polymer. These extractable impurities have a great impact on the spinnability of the melt and lead to waste of raw materials. At present, the industry uses hot water continuous extraction process after nylon 6 polymerization to remove monomers and oligomers in the slices so that the slices meet the requirements of high-speed spinning. However, the extraction, drying, cooling, packaging, remelting and other processes generate a lot of energy consumption, which greatly increases the production cost and three wastes of nylon 6. This is also one of the important reasons that limit the wider application of nylon 6. Therefore, it is crucial to simplify the existing process flow of nylon melt direct spinning to reduce production costs, and it is also conducive to promoting the further development of the nylon fiber industry.

[0003] For example, the "Production Method of High-gloss Nylon 6 Slices Using Caprolactam" disclosed in Chinese patent documents, with the publication number CN102358780A, includes the following steps: (1) preparing caprolactam raw materials; (2) preparing modifiers; (3) subjecting the caprolactam raw materials, modifiers and desalted and deoxygenated water to ring-opening, addition and polycondensation reactions in a prepolymerizer; (4) subjecting the product obtained from the prepolymerization to post-polycondensation reactions in a post-polymerizer; (5) slicing the product obtained in the post-polymerizer; (6) subjecting the slices to pre-extraction and secondary extraction; (7) dehydration, drying and cooling. The disadvantage of this patent is that it is necessary to extract the oligomers in nylon 6, which consumes a lot of energy, resulting in increased production costs and three wastes. Utility Model Content

[0004] The utility model aims to overcome the problem in the prior art that the oligomers in nylon are removed by extraction process, which leads to increased production cost and three wastes discharge. A negative pressure nylon melt spinning pretreatment equipment is provided, which can replace the extraction process to remove the oligomers in the nylon melt, has a simpler process flow, a shorter cycle and lower energy consumption.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model discloses negative pressure nylon melt spinning pre-treatment equipment, comprising a shell, two ends of which are respectively connected with a feed pipe and a discharge pipe, a rotor is installed in the shell, a negative pressure melt channel is formed between the shell and the rotor, and the melt channel is connected with a gas outlet pipe.

[0007] After nylon polymerization and before spinning, the equipment in this application is set up, the original pelletizing, extraction, drying, and remelting processes are eliminated, and the melt is directly processed. After the treatment, the melt can be spun, and the process flow is greatly simplified. After the polymer melt enters the device, it is forced to form a film and update the specific surface area by the rotor arranged inside the shell. Under negative pressure, small oligomer molecules quickly escape into the gas and are discharged from the gas outlet pipe, and the treated nylon 6 melt is extruded from the discharge pipe for spinning.

[0008] Preferably, the shell is covered with a heating jacket, through which the melt can be heated to ensure temperature balance.

[0009] Preferably, the heating jacket is provided with a heat transfer oil inlet and a heat transfer oil outlet, through which heat medium can be provided for the heating jacket.

[0010] Preferably, the rotor is provided with an internal heat medium. By heating the melt through the rotor, the melt material can be heated evenly, so that the temperature difference of the material at different positions is controlled within a certain range.

[0011] Preferably, the present application further comprises a motor and a gearbox, the rotor is mounted on a transmission shaft, and the transmission shaft is driven by the motor and the gearbox. The motor can be used to adjust the rotor rotation speed to achieve the effect of adjusting the target yield and regulating the specific surface area update.

[0012] Preferably, the upper side of the melt channel is connected with a plurality of gas outlet pipes, which are arranged at intervals, and the interval between adjacent gas outlet pipes is 15-20 cm. The gas outlet pipes arranged at intervals can improve the efficiency of gas discharge.

[0013] Preferably, an air extraction pipe is connected above the plurality of gas outlet pipes, and an exhaust port is provided at one end of the air extraction pipe. A vacuum environment can be formed in the housing through the air extraction pipe, thereby accelerating the escape of small molecules.

[0014] Preferably, an anti-extrusion angle is provided between the gas outlet pipe and the barrel channel, so as to prevent the melt from entering the gas outlet pipe.

[0015] Preferably, a pressure pump is installed on the feed pipe.

[0016] Therefore, the utility model has the following beneficial effects: (1) the processing of nylon melt by the rotor replaces the original pelletizing, extraction, drying and remelting processes, thus shortening the process flow; (2) the material is ensured not to be affected by temperature by uniform heating of the melt, thereby improving the material quality; (3) the target output can be adjusted and the specific surface area can be updated by adjusting the rotor speed, and the process is flexible and controllable. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a main structural schematic diagram of the utility model.

[0018] Figure 2 It is a schematic diagram of the structure of the utility model from a top view.

[0019] Figure 3 It is a structural schematic diagram of the discharge port of the utility model.

[0020] In the figure: feed pipe 1, exhaust pipe 2, gas outlet pipe 3, discharge pipe 4, housing 5, rotor 6, gear box 7, motor 8, heating jacket 9, flange 10, sealing ring 11. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0022] Embodiment 1, as Figure 1-2 As shown, a negative pressure nylon melt spinning pre-treatment equipment includes a shell 5, and the two ends of the shell 5 are respectively connected to a feed pipe 1 and a discharge pipe 4, wherein the end connected to the feed pipe 1 is the front end of the shell 5, and the end connected to the discharge pipe 4 is the rear end of the shell 5. A transmission shaft is installed in the shell 5, and a plurality of rotors 6 are installed on the transmission shaft. A negative pressure melt channel is formed between the shell 5 and the rotor 6, and the melt channel is connected to the gas outlet pipe 3. This equipment also includes a motor 8 and a gear box 7, and the transmission shaft is driven by the motor 8 and the gear box 7. Several gas outlet pipes 3 are connected to the upper side of the melt channel, and the plurality of gas outlet pipes 3 are arranged at intervals, and the interval between adjacent gas outlet pipes 3 is 15-20cm. The gas outlet pipes 3 arranged at intervals allow the melt to be exhausted multiple times in the process of being extruded, which can improve the efficiency of gas discharge. The plurality of gas outlet pipes 3 are connected to an exhaust pipe 2 at one end of which an exhaust port is provided. A vacuum environment can be formed in the housing 5 through the exhaust pipe 2, thereby accelerating the escape of small molecules. The inner walls of the gas outlet pipe 3 and the exhaust pipe 2 are both treated with non-stick properties to prevent sticky materials from adhering and accumulating on the surface of the parts. The housing 5 and the discharge pipe 4 are fixedly connected by a flange 10, and the housing and the discharge pipe are sealed by a sealing ring 11.

[0023] A pressure pump is installed on the feed pipe 1. Under the action of the pressure pump, the nylon polymer melt enters the front end of the shell 5 through the feed pipe 1 and flows into the shell 5. The motor 8 and the gear box 7 drive the transmission shaft to rotate through the transmission shaft, and then control the rotation of the rotor 6 on the transmission shaft. During the rotation process, the rotor 6 continuously interacts with the melt, and the melt is driven by the rotor 6 to form a film and continuously increase the specific surface area. At the same time, under the action of the exhaust pipe 2, the gas in the shell 5 is extracted through the gas outlet pipe 3, thereby forming a vacuum environment in the shell 5. After the melt increases the specific surface area, the film-like melt is extracted with a higher efficiency under a vacuum state. Small molecules such as monomers and oligomers are discharged from the gas outlet pipe 3 together with the gas. After the process of multiple small molecule discharges at several gas outlet pipes 3, the melt is squeezed out of the shell 5 from the discharge pipe 4, and the extruded melt can be spun. The structure of the present application is used for pre-spinning treatment, and the contact time between the melt and the container shell 5 is short, which avoids the problem of high viscosity melt sticking to the wall to form gel and affecting the quality of the melt.

[0024] The shell 5 is covered with a heating jacket 9. The heating jacket 9 is provided with a heat transfer oil inlet and a heat transfer oil outlet. Considering that heat is taken out due to the volatilization of small molecules during vacuuming, and the melt temperature is reduced, the heating jacket 9 provided outside the shell 5 heats the melt inside the shell 5, ensuring that heat is evenly supplied to the melt and sufficient to compensate for heat loss, so that the melt temperature is stable, the chemical reaction state in the melt is uniform, and finally the melt viscosity deviation is small. The uniformity of temperature and melt viscosity has an important influence on its spinnability. The design of the utility model can avoid quality fluctuations during the melt processing process to the greatest extent, and obtain a nylon polymer melt that can be spun.

[0025] The process of using the present application for pre-spinning treatment of nylon polymer melt is as follows: the melt is uniformly flowed into the space between the rotor 6 and the housing 5 through the melt inlet pipe under a certain pressure. In this embodiment, the inlet pressure is 1 bar. The melt passing through the inside of the housing 5 is forced to update the specific surface area, becoming a film-like melt, and removing small molecules in a vacuum environment. At the same time, the gas removed is taken out by the gas outlet pipe 3. The heat transfer oil in the jacket and the internal rotor 6 heating pipe ensure uniform temperature in the vacuum chamber. The processed material is extruded from the melt outlet and can be directly spun or made into plastic products.

[0026] Embodiment 2, as Figure 1-2As shown, a negative pressure nylon melt spinning pre-treatment equipment includes a shell 5, and the two ends of the shell 5 are respectively connected to a feed pipe 1 and a discharge pipe 4, wherein the end connected to the feed pipe 1 is the front end of the shell 5, and the end connected to the discharge pipe 4 is the rear end of the shell 5. A transmission shaft is installed in the shell 5, and a plurality of rotors 6 are installed on the transmission shaft. A negative pressure melt channel is formed between the shell 5 and the rotor 6, and the melt channel is connected to the gas outlet pipe 3. This equipment also includes a motor 8 and a gear box 7, and the transmission shaft is driven by the motor 8 and the gear box 7. Several gas outlet pipes 3 are connected to the upper side of the melt channel, and the plurality of gas outlet pipes 3 are arranged at intervals, and the interval between adjacent gas outlet pipes 3 is 15-20cm. The gas outlet pipes 3 arranged at intervals allow the melt to be exhausted multiple times in the process of being extruded, which can improve the efficiency of gas discharge. The plurality of gas outlet pipes 3 are connected to an exhaust pipe 2 at one end of which an exhaust port is provided. A vacuum environment can be formed in the housing 5 through the exhaust pipe 2, thereby accelerating the escape of small molecules. The inner walls of the gas outlet pipe 3 and the exhaust pipe 2 are both treated with non-stick properties to prevent sticky materials from adhering and accumulating on the surface of the parts. The housing 5 and the discharge pipe 4 are fixedly connected by a flange 10, and the housing and the discharge pipe are sealed by a sealing ring 11.

[0027] Furthermore, in this embodiment, an anti-extrusion angle is provided between the gas outlet pipe 3 and the melt channel, and the anti-extrusion angle can prevent the melt from entering the gas outlet pipe 3 during the extrusion process.

[0028] A pressure pump is installed on the feed pipe 1. Under the action of the pressure pump, the nylon polymer melt enters the front end of the shell 5 through the feed pipe 1 and flows into the shell 5. The motor 8 and the gear box 7 drive the transmission shaft to rotate through the transmission shaft, and then control the rotation of the rotor 6 on the transmission shaft. During the rotation process, the rotor 6 continuously interacts with the melt, and the melt is driven by the rotor 6 to form a film and continuously increase the specific surface area. At the same time, under the action of the exhaust pipe 2, the gas in the shell 5 is extracted through the gas outlet pipe 3, thereby forming a vacuum environment in the shell 5. After the melt increases the specific surface area, the film-like melt is extracted with a higher efficiency under a vacuum state. Small molecules such as monomers and oligomers are discharged from the gas outlet pipe 3 together with the gas. After the process of multiple small molecule discharges at several gas outlet pipes 3, the melt is squeezed out of the shell 5 from the discharge pipe 4, and the extruded melt can be spun. The structure of the present application is used for pre-spinning treatment, and the contact time between the melt and the container shell 5 is short, which avoids the problem of high viscosity melt sticking to the wall to form gel and affecting the quality of the melt.

[0029] The shell 5 is covered with a heating jacket 9. The heating jacket 9 is provided with a heat transfer oil inlet and a heat transfer oil outlet. Considering that heat is taken out due to the volatilization of small molecules during vacuuming, and the melt temperature is reduced, the heating jacket 9 provided outside the shell 5 heats the melt inside the shell 5, ensuring that heat is evenly supplied to the melt and sufficient to compensate for heat loss, so that the melt temperature is stable, the chemical reaction state in the melt is uniform, and finally the melt viscosity deviation is small. The uniformity of temperature and melt viscosity has an important influence on its spinnability. The design of the utility model can avoid quality fluctuations during the melt processing process to the greatest extent, and obtain a nylon polymer melt that can be spun.

[0030] The process of using the present application for pre-spinning treatment of nylon polymer melt is as follows: the melt is uniformly flowed into the space between the rotor 6 and the housing 5 through the melt inlet pipe under a certain pressure. In this embodiment, the inlet pressure is 1 bar. The melt passing through the inside of the housing 5 is forced to update the specific surface area, becoming a film-like melt, and removing small molecules in a vacuum environment. At the same time, the gas removed is taken out by the gas outlet pipe 3. The heat transfer oil in the jacket and the internal rotor 6 heating pipe ensure uniform temperature in the vacuum chamber. The processed material is extruded from the melt outlet and can be directly spun or made into plastic products.

[0031] Embodiment three, as Figure 1-2 As shown, a negative pressure nylon melt spinning pre-treatment equipment includes a shell 5, and the two ends of the shell 5 are respectively connected to a feed pipe 1 and a discharge pipe 4, wherein the end connected to the feed pipe 1 is the front end of the shell 5, and the end connected to the discharge pipe 4 is the rear end of the shell 5. A transmission shaft is installed in the shell 5, and a plurality of rotors 6 are installed on the transmission shaft. A negative pressure melt channel is formed between the shell 5 and the rotor 6, and the melt channel is connected to the gas outlet pipe 3. This equipment also includes a motor 8 and a gear box 7, and the transmission shaft is driven by the motor 8 and the gear box 7. Several gas outlet pipes 3 are connected to the upper side of the melt channel, and the plurality of gas outlet pipes 3 are arranged at intervals, and the interval between adjacent gas outlet pipes 3 is 15-20cm. The gas outlet pipes 3 arranged at intervals allow the melt to be exhausted multiple times in the process of being extruded, which can improve the efficiency of gas discharge. The plurality of gas outlet pipes 3 are connected to an exhaust pipe 2 at one end of which an exhaust port is provided. A vacuum environment can be formed in the housing 5 through the exhaust pipe 2, thereby accelerating the escape of small molecules. The inner walls of the gas outlet pipe 3 and the exhaust pipe 2 are both treated with non-stick properties to prevent sticky materials from adhering and accumulating on the surface of the parts. The housing 5 and the discharge pipe 4 are fixedly connected by a flange 10, and the housing and the discharge pipe are sealed by a sealing ring 11.

[0032] Furthermore, in this embodiment, an anti-extrusion angle is provided between the gas outlet pipe 3 and the melt channel, and the anti-extrusion angle can prevent the melt from entering the gas outlet pipe 3 during the extrusion process.

[0033] A pressure pump is installed on the feed pipe 1. Under the action of the pressure pump, the nylon polymer melt enters the front end of the shell 5 through the feed pipe 1 and flows into the shell 5. The motor 8 and the gear box 7 drive the transmission shaft to rotate through the transmission shaft, and then control the rotation of the rotor 6 on the transmission shaft. During the rotation process, the rotor 6 continuously interacts with the melt, and the melt is driven by the rotor 6 to form a film and continuously increase the specific surface area. At the same time, under the action of the exhaust pipe 2, the gas in the shell 5 is extracted through the gas outlet pipe 3, thereby forming a vacuum environment in the shell 5. After the melt increases the specific surface area, the film-like melt is extracted with a higher efficiency under a vacuum state. Small molecules such as monomers and oligomers are discharged from the gas outlet pipe 3 together with the gas. After the process of multiple small molecule discharges at several gas outlet pipes 3, the melt is squeezed out of the shell 5 from the discharge pipe 4, and the extruded melt can be spun. The structure of the present application is used for pre-spinning treatment, and the contact time between the melt and the container shell 5 is short, which avoids the problem of high viscosity melt sticking to the wall to form gel and affecting the quality of the melt.

[0034] The shell 5 is covered with a heating jacket 9 on the outside. The heating jacket 9 is provided with a heat transfer oil inlet and a heat transfer oil outlet. Furthermore, the rotor 6 of the present application is also provided with an internal heat medium, which can be a heating wire structure or a heat transfer oil. Considering that heat is taken out due to the volatilization of small molecules during vacuuming, and the melt temperature is reduced, the heat medium located at the rotor 6 inside the shell 5 is designed to heat the melt, and the heating jacket 9 located outside the shell 5 supplies heat at the same time, so as to ensure that heat is evenly supplied to the melt and is sufficient to compensate for heat loss, so that the melt temperature is stable, the chemical reaction state in the melt is uniform, and finally the melt viscosity deviation is small. The uniformity of temperature and melt viscosity has an important influence on its spinnability. The design of the utility model can avoid quality fluctuations during the melt processing process to the greatest extent, and obtain a nylon polymer melt that can be spun.

[0035] The process of using the present application for pre-spinning treatment of nylon polymer melt is as follows: the melt is uniformly flowed into the space between the rotor 6 and the housing 5 through the melt inlet pipe under a certain pressure. In this embodiment, the inlet pressure is 1 bar. The melt passing through the inside of the housing 5 is forced to update the specific surface area, becoming a film-like melt, and removing small molecules in a vacuum environment. At the same time, the gas removed is taken out by the gas outlet pipe 3. The heat transfer oil in the jacket and the internal rotor 6 heating pipe ensure uniform temperature in the vacuum chamber. The processed material is extruded from the melt outlet and can be directly spun or made into plastic products.

Claims

1. A negative pressure nylon melt spinning pre-treatment equipment, characterized in that: It comprises a shell, two ends of which are respectively connected with a feed pipe and a discharge pipe, a rotor is installed in the shell, a negative pressure melt channel is formed between the shell and the rotor, and the melt channel is connected with a gas outlet pipe.

2. The negative pressure nylon melt spinning pre-treatment equipment according to claim 1, characterized in that: The shell body is covered with a heating jacket.

3. The negative pressure nylon melt spinning pre-treatment equipment according to claim 2, characterized in that: The heating jacket is provided with a heat transfer oil inlet and a heat transfer oil outlet.

4. The negative pressure nylon melt spinning pre-treatment equipment according to claim 1, characterized in that: An internal heat medium is arranged in the rotor.

5. The negative pressure nylon melt spinning pre-treatment equipment according to claim 1, characterized in that: It also includes a motor and a gear box. The rotor is installed on a transmission shaft, and the transmission shaft is driven by the motor and the gear box.

6. The negative pressure nylon melt spinning pre-treatment equipment according to claim 1, characterized in that: The upper side of the melt channel is connected with a plurality of gas outlet pipes, which are arranged at intervals, and the interval between adjacent gas outlet pipes is 15-20 cm.

7. The negative pressure nylon melt spinning pre-treatment equipment according to claim 6, characterized in that: An exhaust pipe is connected above the plurality of gas outlet pipes, and an exhaust port is arranged at one end of the exhaust pipe.

8. The negative pressure nylon melt spinning pre-treatment equipment according to claim 6, characterized in that: An anti-extrusion angle is arranged between the gas outlet pipe and the melt channel.

9. A negative pressure nylon melt spinning pre-treatment equipment according to any one of claims 1 to 8, characterized in that: A pressure pump is installed on the feed pipe.

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