A PK post-processing system and process

Abstract

A PK post-processing system includes a crusher, a polymer dryer, an extruder, and an underwater pelletizer. The crusher's inlet is connected to the PK polymerization unit, and its outlet supplies material to the polymer dryer. The polymer dryer is connected to a negative pressure source, and its outlet supplies material to the extruder via a powder cooler. The extruder's inlet is also equipped with a mixing hopper connected to an antioxidant source, and its outlet supplies material to the underwater pelletizer via a melt pump. This invention has a simple structure, is easy to operate, and can ensure the production of PK products with stable quality.

Description

Technical Field

[0001] This invention relates to the chemical industry, and in particular to a PK post-treatment system and process. Background Technology

[0002] PK stands for polyketide resin, a smooth, white, glossy, hard, and dense material with high elastic modulus, high rigidity and hardness. Its specific strength and specific rigidity are close to those of metals, and it has a low coefficient of friction, good wear resistance, and good dimensional stability. Polyketide resin can partially replace metals such as copper, zinc, aluminum, and steel in industries such as automobiles, machinery manufacturing, precision instruments, office and household appliances, and military applications. Due to its high hardness and wear resistance, polyketide resin is widely used in the manufacture of various gears, rollers, bearings, conveyor belts, springs, cams, bolts, and structural components of mechanical equipment such as pump bodies, housings, impeller friction bearings, etc.

[0003] PK is a linear crystalline polymer obtained by alternating copolymerization of carbon monoxide, ethylene, and propylene. The resulting material contains solvents and impurities that need to be removed. Furthermore, since PK polyketide resin is a crystalline plastic, once the melting point is reached, the melt viscosity drops rapidly. At the same time, if the melt is heated for too long, it will lead to severe thermal degradation and generate more impurities. These factors result in the unstable quality of PK plastics obtained through current processing.

[0004] Therefore, designing a device that can stabilize the post-processing of PK polyketone resin to enhance the competitiveness of PK products is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] One of the objectives of this invention is to address the shortcomings of existing technologies by providing a PK post-processing system that is simple in structure, easy to operate, and can guarantee the production of PK products with stable quality.

[0006] The second objective of this invention is to provide a process for processing PK polymers using the above-mentioned post-processing system. This process is simple, has low processing costs, and can produce PK products with stable quality, thereby enhancing the market competitiveness of PK products.

[0007] One of the technical solutions to achieve the objective of this invention is: a PK post-processing system, comprising a crusher, a polymer dryer, an extruder, and an underwater pelletizer. The feed inlet of the crusher is connected to the PK polymerization unit, and the discharge outlet of the crusher supplies material to the polymer dryer. The polymer dryer is connected to a negative pressure source, and the discharge outlet of the polymer dryer supplies material to the extruder via a powder cooler. The feed end of the extruder is also equipped with a mixing feed hopper connected to an antioxidant source, and the discharge outlet of the extruder supplies material to the underwater pelletizer via a melt pump.

[0008] The polymer dryer is a jacketed horizontal spiral dryer. The gas phase outlet of the polymer dryer is connected to a gas-liquid separator via a condenser. The gas phase outlet of the gas-liquid separator is connected to a negative pressure source. The liquid phase outlet of the gas-liquid separator is connected to a coarse solvent pump to recover the solvent.

[0009] The extruder is connected to an induced draft fan, and the downstream end of the induced draft fan is discharged to the outside via a spray scrubbing tower.

[0010] The second technical solution to achieve the objective of this invention is: a process for synthesizing PK catalysts using any of the above-mentioned production systems, comprising the following steps:

[0011] 1) The slurry containing PK polymer discharged from the polymerization unit is sent to a crusher and crushed to a particle size of less than 0.5mm;

[0012] 2) The crushed slurry is sent to a polymer dryer and dried at a pressure of 50 mmH2O and a temperature of 165°C for 10 min.

[0013] 3) After drying and cooling, the material is mixed with the anti-aging agent and then fed into the extruder. The extrusion temperature is controlled at 180-200℃ and the screw speed is 200r / min.

[0014] 4) The extruded material is granulated underwater to obtain the target product.

[0015] Step 1) The polymer concentration in the slurry is 70 wt%, and the remainder is solvent.

[0016] Step 2) The polymer dryer uses 2.5 MPa (G) saturated steam to provide heat.

[0017] Step 3) Use nitrogen as a circulating cooling medium. The flow ratio of the dried material to the anti-aging machine is 1280:1.

[0018] The above technical solution has the following beneficial effects:

[0019] 1. The PK post-processing system includes a crusher, a polymer dryer, an extruder, and an underwater pelletizer. The crusher crushes the materials in the slurry, ensuring uniform particle size within a specified range to guarantee effective drying, mixing, and melting. The crusher's inlet is connected to the PK polymerization unit, allowing direct use of the slurry discharged from the unit as raw material, reducing intermediate processing costs. The crusher's outlet feeds the polymer dryer, which is connected to a negative pressure source to lower its operating temperature and fully recover solvents. The polymer dryer's outlet feeds the extruder via a powder cooler, preventing direct contact and reaction between the high-temperature powder and the anti-aging agent, ensuring uniform contact between the anti-aging agent and the powder, thus guaranteeing the quality stability of the PK product. The extruder's inlet is also equipped with a mixing hopper connected to the anti-aging agent source, and the extruder's outlet feeds the underwater pelletizer via a melt pump.

[0020] 2. The polymer dryer is a jacketed horizontal spiral dryer. The gas phase outlet of the polymer dryer is connected to a gas-liquid separator via a condenser, which converts the vaporized solvent into a liquid phase, which is then separated by the gas-liquid separator. The gas phase outlet of this gas-liquid separator is connected to a negative pressure source, and the liquid phase outlet is connected to a coarse solvent pump to recover the solvent. This provides a vacuum for the polymer dryer and also enables solvent recovery and reuse, meeting the actual needs of the enterprise.

[0021] 3. In the post-processing steps of this invention, the slurry containing PK polymer is first pulverized into particles smaller than 0.5mm using a pulverizer. This facilitates the downstream drying process, improves mixing efficiency, and enhances the melting effect in the extruder. Before being fed into the extruder for melting, the material is cooled at high temperature to prevent some of the hot powder from reacting directly with the anti-aging agent. Instead, it is fully mixed and melted before extrusion, ensuring the quality stability of the PK product. By controlling the extruder temperature to 180-200℃ and shortening the extruder residence time to 15 minutes, the decomposition of PK during the modification process can be effectively prevented, improving material yield.

[0022] The following description, in conjunction with the accompanying drawings and specific embodiments, provides further details. Attached Figure Description

[0023] Figure 1 This is a connection diagram of the post-processing system of the present invention.

[0024] In the attached diagram, 1 is a crusher, 2 is a polymer dryer, 3 is an extruder, 4 is an underwater pelletizer, 5 is a powder cooler, 6 is a mixing feed hopper, 7 is a melt pump, 8 is a condenser, 9 is a gas-liquid separator, and 10 is an induced draft fan. Detailed Implementation

[0025] In this invention, the antioxidant IR245 (triethylene glycol bis[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate]) is used.

[0026] Anti-aging agent standards and purity

[0027]

[0028] Example 1

[0029] See Figure 1 The PK post-processing system includes a crusher 1, a polymer dryer 2, an extruder 3, and an underwater pelletizer 4. The feed inlet of the crusher 1 is connected to the PK polymerization unit, and the discharge outlet of the crusher 1 supplies material to the polymer dryer 2. The polymer dryer 2 is connected to a negative pressure source, and its discharge outlet supplies material to the extruder 3 via a powder cooler 5. In this embodiment, the polymer dryer 2 is a jacketed horizontal spiral dryer. The gas phase outlet of the polymer dryer 2 is connected to a gas-liquid separator 9 via a condenser 8. The gas phase outlet of the gas-liquid separator 9 is connected to the negative pressure source, and the liquid phase outlet of the gas-liquid separator recovers solvent via a coarse solvent pump. The feed end of the extruder 3 is also equipped with a mixing feed hopper 6, which is connected to an antioxidant source. The discharge outlet of the extruder 3 supplies material to the underwater pelletizer 4 via a melt pump 7. Specifically, the extruder 3 is connected to an induced draft fan 10, and the downstream end of the induced draft fan 10 discharges material to the outside via a spray scrubbing tower.

[0030] The specifications of each piece of equipment are as follows:

[0031]

[0032]

[0033] Example 2

[0034] The PK slurry was processed using the post-processing system of Example 1:

[0035] 1) The slurry containing 70wt% PK polymer discharged from the PK polymerization unit, with a flow rate of 9.238t / h, is sent to the crusher for pulverization to make the polyketone resin powder particle size less than 0.5mm;

[0036] 2) The pulverized material is sent to a polymer dryer, with working conditions of 50 mmH2O and 165℃, using 2.5 MPa(G) saturated steam to provide heat, and a residence time of 10 min;

[0037] 3) The dried powder has a flow rate of 6.4 t / h and enters the powder cooler. Nitrogen is used as the circulating cooling carrier to cool the powder. The gas phase outlet flow rate of the polymer dryer is 2.792 t / h. After condensation, the gas phase outlet (non-condensable gas) flow rate of the gas-liquid separator is 0.006 t / h and enters the negative pressure source. The liquid phase outlet flow rate is 2.786 t / h and is sent to the solvent recovery unit.

[0038] 4) After cooling, the powder is mixed with the anti-aging agent (IR245, flow rate 0.005t / h) and fed into the extruder. The residence time in the extruder is 15min, the pressure is 0.02MPa(A), and heat transfer oil is used as the heating medium. The inlet temperature is 230℃ and the outlet temperature is 220℃, so that the extruder temperature is maintained between 180-200℃.

[0039] 5) The molten slurry is fed into an underwater pelletizer and sheared into granular PK pellets. After liquid-solidification and drying, the pellets are sent to the product silo.

[0040]

[0041]

[0042] Example 3

[0043] Dryer and extruder operating conditions 1

[0044] Dryer operating conditions unit numerical values Dryer residence time minute 12 Annual operation time Hour 8000 Dryer production capacity tons / year 62500 Dryer temperature ℃ 165 Dryer vacuum <![CDATA[mmH2O]]> 50 Dryer steam inlet temperature ℃ 231℃ Dryer steam inlet pressure (saturation) MPa(G) 2.5 Extruder operating conditions unit numerical values Extruder residence time minute 8 Annual operation time Hour 8000 Extruder production capacity tons / year 62500 Extruder temperature ℃ 200 Extruder vacuum MPa(A) 0.02 Thermal oil extruder inlet temperature ℃ 230 Thermal oil extruder outlet temperature ℃ 220

[0045] Dryer and extruder operating conditions 2

[0046]

[0047]

[0048] Dryer and extruder operating conditions 3

[0049] Dryer operating conditions unit numerical values Dryer residence time minute 15 Annual operation time Hour 8000 Dryer production capacity tons / year 50000 Dryer temperature ℃ 165 Dryer vacuum <![CDATA[mmH2O]]> 50 Dryer steam inlet temperature ℃ 231℃ Dryer steam inlet pressure (saturation) MPa(G) 2.5 Extruder operating conditions unit numerical values Extruder residence time minute 10 Annual operation time Hour 8000 Extruder production capacity tons / year 50000 Extruder temperature ℃ 185 Extruder vacuum MPa(A) 0.02 Thermal oil extruder inlet temperature ℃ 230 Thermal oil extruder outlet temperature ℃ 220

[0050] Dryer and extruder operating conditions 4

[0051] Dryer operating conditions unit numerical values Dryer residence time minute 16.5 Annual operation time Hour 8000 Dryer production capacity tons / year 45455 Dryer temperature ℃ 168 Dryer vacuum <![CDATA[mmH2O]]> 50 Dryer steam inlet temperature ℃ 231℃ Dryer steam inlet pressure (saturation) MPa(G) 2.5 Extruder operating conditions unit numerical values Extruder residence time minute 11 Annual operation time Hour 8000 Extruder production capacity tons / year 45455 Extruder temperature ℃ 182 Extruder vacuum MPa(A) 0.02 Thermal oil extruder inlet temperature ℃ 230 Thermal oil extruder outlet temperature ℃ 220

[0052] Dryer and extruder operating conditions 5

[0053] Dryer operating conditions unit numerical values Dryer residence time minute 18 Annual operation time Hour 8000 Dryer production capacity tons / year 41667 Dryer temperature ℃ 169 Dryer vacuum <![CDATA[mmH2O]]> 50 Dryer steam inlet temperature ℃ 231℃ Dryer steam inlet pressure (saturation) MPa(G) 2.5 Extruder operating conditions unit numerical values Extruder residence time minute 12 Annual operation time Hour 8000 Extruder production capacity tons / year 41667 Extruder temperature ℃ 180 Extruder vacuum MPa(A) 0.02 Thermal oil extruder inlet temperature ℃ 230 Thermal oil extruder outlet temperature ℃ 220

Claims

1. A PK post-processing system, characterized in that: It includes a crusher (1), a polymer dryer (2), an extruder (3), and an underwater pelletizer (4). The feed inlet of the crusher (1) is connected to the PK polymerization unit. The slurry containing PK polymer discharged from the polymerization unit is sent to the crusher and crushed to a particle size of less than 0.5 mm. The discharge outlet of the crusher (1) supplies material to the polymer dryer (2). The polymer dryer (2) is connected to a negative pressure source. The outlet of the polymer dryer (2) supplies material to the extruder (3) through the powder cooler (5). The feed end of the extruder (3) is also equipped with a mixing feed hopper (6), which is connected to the antioxidant source. After drying, the material is cooled and mixed with the antioxidant before entering the extruder. The extrusion temperature is controlled at 180-200℃. The outlet of the extruder (3) supplies material to the underwater pelletizer (4) through the melt pump (7).

2. The PK post-processing system according to claim 1, characterized in that: The polymer dryer (2) is a jacketed horizontal spiral dryer. The gas phase outlet of the polymer dryer (2) is connected to a gas-liquid separator (9) via a condenser (8). The gas phase outlet of the gas-liquid separator (9) is connected to a negative pressure source. The liquid phase outlet of the gas-liquid separator is connected to a coarse solvent pump to recover the solvent.

3. The PK post-processing system according to claim 1, characterized in that: The extruder (3) is connected to the induced draft fan (10), and the downstream end of the induced draft fan (10) is discharged to the outside through the spray scrubbing tower.

4. A process for treating PK polymers using any one of the post-processing systems of claims 1-3, characterized in that, Includes the following steps: 1) The slurry containing PK polymer discharged from the polymerization unit is sent to a crusher and crushed to a particle size of less than 0.5mm; 2) The crushed slurry is sent to a polymer dryer and dried at a pressure of 50 mmH2O and a temperature of 165°C for 10 minutes. 3) After drying and cooling, the material is mixed with the anti-aging agent and then fed into the extruder. The extrusion temperature is controlled at 180-200℃ and the screw speed is 200r / min. 4) The extruded material is granulated underwater to obtain the target product.

5. The process according to claim 4, characterized in that, Step 1) The polymer concentration in the slurry is 70 wt%, and the remainder is solvent.

6. The process according to claim 4, characterized in that, Step 2) The polymer dryer uses 2.5 MPaG saturated steam to provide heat.

7. The process according to claim 4, characterized in that, Step 3) Use nitrogen as a circulating cooling medium, and the flow ratio of dried material to antioxidant is 1280:1.

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