Polyether-ether-ketone refining treatment system and method

Abstract

The invention discloses a polyether-ether-ketone refining treatment system and a polyether-ether-ketone refining treatment method. The polyether-ether-ketone refining treatment system comprises a cleaning device, a reboiler I, a reboiler II, a reboiler III, a separator I, a separator II, a temporary storage tank I and a temporary storage tank II, organic solvent cleaning, residual solvent evaporation and water washing are achieved in the cleaning device, and due to the fact that after materials are cleaned by the organic solvent and water, the two solvents are different in post-treatment mode. An organic solvent steam washing process is added between the organic solvent washing process and the water washing process, so that organic solvent steam is fed after the organic solvent washing, the organic solvent steam upwards penetrates through materials and carries out a small amount of remaining diphenyl sulfone among PEEK particles, and then the water washing process is performed. By applying the PEEK refining treatment system and the PEEK refining treatment method, the consumption of organic solvents such as acetone and ethanol can be reduced by 50%, the energy consumption for solvent recovery can be directly saved by 50%, meanwhile, the productivity of the device can be improved by the process, and the direct cost of the product is greatly reduced in the aspects of labor and equipment depreciation.

Description

Technical Field

[0001] The invention relates to a polyetheretherketone refining treatment system and method, belonging to the field of polymer material refining equipment and technology. Background Art

[0002] Polyetheretherketone is a new type of polymer made by high-temperature polymerization using diphenyl sulfone, difluorobenzophenone, bisphenol compounds and a large amount of inorganic potassium salt and inorganic sodium salt as raw materials. The product polyetheretherketone has extremely stringent requirements on purity. After the polymerization, the product will be mixed with a large amount of impurities such as reaction raw materials and side reactions. The impurities are mainly diphenyl sulfone, potassium fluoride salt and sodium fluoride salt. Usually, one or more organic solvents and purified water are used to wash and purify the product to control the impurity content below 10ppm.

[0003] How to improve product purity has become the key to the quality control of polyetheretherketone in this industry.

[0004] For diphenyl sulfone, the product polyetheretherketone is usually stirred and washed multiple times with an organic solvent to gradually remove diphenyl sulfone from the material. This process has the following problems: a large amount of solvent is required, a large amount of energy is consumed to recover the solvent after washing, the number of organic solvent washings is generally 13-15 times, and the working hours are long.

[0005] Fluoride salt impurities are usually removed by washing with pure water 10-12 times. The washing water can be discharged only after sewage treatment, and the sewage treatment cost is high.

[0006] Figure 1 The conventional process flow and equipment for implementing the above washing are shown. First, the material is extracted, soaked and stirred 12-15 times in an extraction kettle with stirring and heating functions using an organic solvent such as ethanol or acetone, and then washed and filtered with organic solvents for multiple times; secondly, the solid phase material in the kettle is transferred to a residual solvent evaporator to evaporate the residual organic solvent until the residual organic solvent in the material is completely removed; finally, the material with the organic solvent residue removed is transferred to a water washing kettle, and purified water is added to perform 10-12 fluoride salt washings to obtain a high-purity product, polyetheretherketone. At the same time, after the residual solvent in the material is evaporated and recovered, it needs to be purified and recovered in a purification tower, and the organic solvent consumed in the extraction needs to be evaporated and recovered separately (this part of the equipment is not included in the conventional process diagram). Because the amount of solvent extraction is large and the number of times is large, the volume of organic solvent to be processed, recovered and purified is extremely large, the volume of equipment required is large, and the loss and waste of energy consumption are also relatively serious.

[0007] Based on the above analysis, how to use a set of equipment or a new process to effectively avoid the problems of a large number of equipment, long process flow, high energy consumption, large space and inconvenient operation has become the key to the refining of polyetheretherketone. Summary of the invention

[0008] The purpose of the present invention is to provide a polyetheretherketone refining processing system and method thereof, which optimizes the process route, effectively integrates multiple unit equipment together, realizes process crossover, effectively links the unit equipment, integrates multiple separate modules together, thereby reducing the number of production equipment, effectively reducing the equipment's footprint, and releasing more effective space.

[0009] The polyetheretherketone refining treatment system provided by the present invention comprises a washer, a reboiler I, a reboiler II, a reboiler III, a separator I, a separator II, a temporary storage tank I and a temporary storage tank II; The lower ends of the separator I and the separator II are provided with a gas-liquid separation section; The top of the cleaning vessel is provided with a solid feeding port, and the bottom is connected to the temporary storage tank II; A tangential feed port is provided on the side wall of the cleaning device, and the tangential feed port is connected to the outlet of the reboiler I, and an organic solvent feed pipeline is provided on the connecting pipeline; the inlet of the reboiler I is connected to the temporary storage tank II; An organic solvent vapor inlet is provided on the side wall of the cleaning vessel, and the organic solvent vapor inlet is connected to the reboiler III; A gas phase outlet is provided on the side wall of the cleaning device, and the gas phase outlet is connected to the separator I, and the separator I is connected to a reflux tank, and part of the organic solvent in the reflux tank is transported out, part of it is refluxed to the separator I, and part of it is returned to the cleaning device as a washing liquid; The outlet of the reboiler I is also connected to the lower part of the separator I; A pure water inlet is provided on the side wall of the cleaning device, and the bottom is connected to the temporary storage tank I, the temporary storage tank I is connected to the reboiler II, the outlet of the reboiler II is connected to the separator II, and the water phase outlet of the separator II is connected to the pure water inlet.

[0010] In the polyetheretherketone refining treatment system of the present invention, a leaching distributor is provided in the cleaning device for the leaching liquid to pass through; A steam distributor is arranged inside the cleaning device for allowing the organic solvent steam to pass through.

[0011] An organic solvent washing inlet is provided on the side wall of the cleaning device; In the polyetheretherketone refining treatment system of the present invention, one end of the organic solvent elution inlet is connected to the separator I, and the other end is connected to the elution distributor.

[0012] As one of the main raw materials of polyetheretherketone (PEEK), diphenyl sulfone is added in excess during the reaction, so the product contains a large amount of diphenyl sulfone. The product can be cleaned with organic solvents such as acetone and ethanol. The main cleaning target is diphenyl sulfone. Both PEEK and diphenyl sulfone are high-melting-point substances and are solid at room temperature. However, peek has a certain particle size and cannot be dissolved by acetone or water. However, diphenyl sulfone is easily soluble in organic solvents such as acetone and ethanol. Salt impurities are not easily soluble in acetone but are easily soluble in water.

[0013] Based on the polyetheretherketone refining treatment system, the present invention further provides a polyetheretherketone refining treatment method, including an organic solvent cleaning step, an organic solvent eluting step, an organic solvent steam washing step and a water washing step performed in the polyetheretherketone refining treatment system.

[0014] Specifically, the organic solvent cleaning steps are as follows: The organic solvent is fed into the cleaning device through the tangential feed port to completely immerse the material for cleaning; the mixed solution after cleaning flows into the temporary storage tank II, a part of which passes through the reboiler I and is forced to circulate and heat with the material in the cleaning device to maintain the extraction temperature, and the other part is subjected to the evaporation process. As the above operation continues, acetone is continuously circulated to extract diphenyl sulfone, the diphenyl sulfone content in PEEK continues to decrease, and at the same time, the diphenyl sulfone content in the temporary storage tank II continues to increase. When the diphenyl sulfone content in the temporary storage tank II increases to a certain concentration, the solvent-diphenyl sulfone mixture can be intermittently extracted to enter the evaporation process.

[0015] The liquid outlet of the cleaning device is provided with a filter cap to intercept PEEK solids, and the outlet amount of the mixture of organic solvent and diphenyl sulfone after cleaning is controlled by controlling the opening of the liquid outlet valve; In order to ensure the mixed cleaning effect of the solvent and PEEK, the present invention, on the one hand, controls the flow rate of the material pump to promote the mixing degree of the material in the cleaning device, and on the other hand, adopts a tangential feeding form to provide a material tumbling state. At the same time, high-purity nitrogen can be blown into the bottom of the cleaning device to promote PEEK tumbling, thereby making it more conducive for the diphenyl sulfone embedded between the PEEK to be dissolved by the solvent.

[0016] Specifically, the organic solvent elution step is as follows: The organic solvent enters from the organic solvent elution inlet at the top of the cleaning device for elution. The mixed liquid after elution flows to the temporary storage tank II, and then is heated and vaporized by the reboiler I. The vaporized organic solvent enters the gas-liquid separation section at the bottom of the separator I to achieve gas-liquid separation. The gas phase enters the packing of the separator I, and flows to the reflux tank after condensation. A part of it is output, a part of it is refluxed to the separator I, and a part of it is returned to the cleaning device as elution liquid. The liquid phase is partially extracted to the temporary storage tank II. When the diphenyl sulfone content in the temporary storage tank II8 increases to a specific concentration, the solvent-diphenyl sulfone mixture can be intermittently extracted to enter the evaporation process. In order to ensure the liquid holding capacity of the system, fresh organic solvent needs to be appropriately added after the mixed liquid of the solvent and diphenyl sulfone is extracted. When the diphenyl sulfone content in PEEK is reduced to the required content, the solvent elution operation can be stopped.

[0017] Specifically, the organic solvent steam washing steps are as follows: After being vaporized in the reboiler III, the organic solvent enters the steam distributor in the washer from the organic solvent steam inlet, passes through the material upward for washing (taking out a small amount of diphenyl sulfone remaining between the PEEK particles), flows out from the organic solvent gas phase outlet into the separator I, and flows into the reflux tank after condensation, with a part of it being output externally, a part of it being refluxed to the separator I, and a part of it being returned to the washer as eluent.

[0018] After the organic solvent washing step, the organic solvent elution step, and the organic solvent steam washing step, the PEEK no longer contains diphenyl sulfone, and an ultrapure water washing solvent operation is performed at this time. The washing steps are as follows: Water is input into the cleaning device through the pure water inlet to wash the material (ultrapure water can wash away the residual solvent in the system. At this time, the ultrapure water contains organic solvents, and pure water dissolves a small amount of sodium fluoride contained in PEEK); the mixed liquid after washing flows to the temporary storage tank I, and is heated by the reboiler II. After heating, the organic solvent in the water is vaporized, and the vaporized organic solvent enters the separator II. The organic solvent enters the separator II as a gas phase, refluxes to the gas-liquid separation section after condensation, and is extracted to the outside of the system (wastewater). The liquid phase in the separator II is refluxed to the cleaning device. The temporary storage tank I intermittently extracts a sodium fluoride aqueous solution without organic solvents, and appropriately supplements fresh pure water. The sodium fluoride impurities are cleaned by multiple water replenishment and external washing water.

[0019] When the crude PEEK no longer contains solvent and sodium fluoride, water can be discharged from the water washing section of the washer, and the discharge valve at the bottom of the washer is opened to allow the PEEK to be discharged to the lower pipeline by gravity and enter the next process.

[0020] By applying the PEEK refining treatment system and method of the present invention, the consumption of organic solvents such as acetone and ethanol can be reduced by 50%, and the energy consumption used for solvent recovery can be directly saved by 50%. At the same time, through the process of the present invention, the extraction kettle, the residual solvent evaporation kettle and the water washing kettle are integrated into a cleaning device, which reduces the area occupied by the system, improves the production capacity of the device, and greatly reduces the direct cost of the product in terms of labor and equipment depreciation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of the traditional refining process of existing polyetheretherketone.

[0022] Figure 2 It is a schematic diagram of the polyetheretherketone refining treatment system of the present invention.

[0023] Figure 3 It is a schematic diagram of a cleaning device in the polyetheretherketone refining treatment system of the present invention.

[0024] Figure 4 It is a cross-sectional view of the rinse distributor in the cleaning device of the present invention.

[0025] Figure 5 It is a cross-sectional view of the steam distributor in the cleaning device of the present invention.

[0026] Figure 6 It is a schematic diagram of tangential feeding of the tangential feeding port in the cleaning device of the present invention.

[0027] Figure 7 It is a structural diagram of the filter cap in the cleaning device of the present invention.

[0028] 1. Cleaner; 2. Reboiler I; 3. Reboiler II; 4. Reboiler III; 5. Separator I; 6. Separator II; 7. Temporary storage tank I; 8. Temporary storage tank II; 9. Reflux tank. DETAILED DESCRIPTION

[0029] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0030] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0031] like Figure 2 and Figure 3 As shown, the polyetheretherketone refining treatment system provided by the present invention includes a cleaner 1, a reboiler Ⅰ2, a reboiler Ⅱ3, a reboiler Ⅲ4, a separator Ⅰ5, a separator Ⅱ6, a temporary storage tank Ⅰ7, a temporary storage tank Ⅱ8 and a reflux tank 9.

[0032] like Figure 3As shown, the top of the cleaning device 1 is provided with a solid feed port k and a gas phase outlet x, the side is provided with a pure water inlet q, an organic solvent elution inlet u, a tangential feed port c, and an organic solvent steam inlet r, and the bottom is provided with an organic solvent discharge port t, a solid discharge port p and a washing water discharge port s; wherein the solid discharge port p is also connected to the inert gas inlet d, and a elution distributor is provided at the upper end AA section of the cleaning device 1, which is used for the eluent of water or organic solvent to enter, and the structure of the elution distributor is as shown in FIG. Figure 4 As shown, one side is provided with reinforcing ribs; the lower end BB section inside the cleaning device 1 is provided with an organic solvent vapor distributor, which is used for the organic solvent vapor to enter, and the structure is as shown Figure 5 As shown, one side is also provided with reinforcing ribs.

[0033] The solid feeding port k is used to feed the PEEK-diphenyl sulfone solid to be purified.

[0034] The gas phase outlet x is connected to the separator Ⅰ5, and the gas phase organic solvent (acetone, ethanol, etc.) discharged from the scrubber 1 enters the separator Ⅰ5.

[0035] Pure water enters from the pure water inlet q of the cleaning device 1. The pure water inlet q is provided with two parallel feed pipelines. One pipeline is connected to the outlet of the separator Ⅱ 6 for introducing the rinsing water discharged from the separator Ⅱ 6, and the other pipeline is introduced with fresh pure water.

[0036] The organic solvent washing inlet u is connected to the reflux tank 9, and part of the organic solvent in the reflux tank 9 enters the cleaning device 1 as the washing liquid; the organic solvent (acetone or ethanol, etc.) enters tangentially from the tangential feed port c of the cleaning device 1, and the material tangentially enters the state as shown in Figure 6 As shown, the material is continuously tumbling. The tangential feed port c is provided with two parallel feed pipelines, one of which is connected to the outlet of the reboiler Ⅰ2, and the other is fed with fresh organic solvent, such as acetone.

[0037] The organic solvent vapor inlet r is connected to the reboiler III4, and organic solvent vapor, such as acetone vapor, is introduced.

[0038] The organic solvent outlet t is connected to the temporary storage tank II 8. After the diphenyl sulfone in the PEEK in the cleaning device 1 is extracted by the organic solvent, the diphenyl sulfone and organic solvent mixture is discharged into the temporary storage tank II 8. Figure 6 The filter cap w shown prevents the solid inside from being discharged with the solution.

[0039] The solid discharge port p is used for the refined PEEK to be discharged from the cleaning device 1. The solid discharge port p is also connected to the inert gas inlet d.

[0040] The washing water outlet s is connected to the temporary storage tank Ⅰ7, and the ultrapure water containing organic solvent and sodium fluoride flows into the temporary storage tank Ⅰ7 after washing. Figure 7 The filter cap shown prevents the solids inside from being discharged with the solution.

[0041] The inlet of the reboiler Ⅰ2 is connected to the temporary storage tank Ⅱ8. The outlet of the reboiler Ⅰ2 is connected to the tangential feed port c of the scrubber 1 for heating the organic solvent and returning it to the scrubber 1 for extraction; the outlet of the reboiler Ⅰ2 is also connected to the lower part of the separator Ⅰ5.

[0042] The bottom inlet of the reboiler II 3 is connected to the temporary storage tank I 7, and the outlet is connected to the lower inlet of the separator II 6 for heating water.

[0043] The reboiler III 4 is connected to the organic solvent vapor inlet r of the scrubber 1 for providing organic solvent vapor.

[0044] Separator Ⅰ5 is used to separate diphenyl sulfone from organic solvent. The lower part of separator Ⅰ5 is provided with 2 inlets and 1 outlet. The first inlet is connected to the gas phase outlet x of cleaning device 1, the second inlet is connected to the outlet of reboiler Ⅰ2, and the lower outlet of separator Ⅰ5 is connected to temporary storage tank Ⅱ8. The upper part of separator Ⅰ5 is provided with 1 inlet and 1 outlet. The upper inlet is connected to the outlet of reflux tank 9, and the upper outlet is connected to the inlet of reflux tank 9 through a condenser. The condenser outlet a is vented. The organic solvent vaporized in cleaning device 1 carries a small amount of vaporized diphenyl sulfone into separator Ⅰ5 through the gas phase outlet x. The organic solvent is in the gas phase and diphenyl sulfone is in the liquid phase. Then the gas-liquid separation is realized through the gas-liquid separation section. The gas phase is condensed by the condenser and flows to the solvent reflux tank 9 by gravity. The liquid phase is discharged into the temporary storage tank Ⅱ8.

[0045] Separator II6 is used to separate water and organic solvent. It has 1 inlet and 1 outlet at the bottom. The lower inlet is connected to the outlet of reboiler II3, and the lower outlet is connected to the pure water inlet q of cleaning device 1, and washing water is introduced into cleaning device 1. The top is provided with 2 outlets, one outlet is connected to the sewage pipe m, and the other outlet is connected to the condenser. The organic solvent vaporized by reboiler II3 carries a small amount of water vapor into separator II6. The organic solvent is in gas phase and water is in liquid phase. Gas-liquid separation is achieved in the gas-liquid separation section. After condensation, part of the gas phase organic solvent flows back to separator II6, and part is discharged to sewage pipe m and discharged to sewage.

[0046] The inlet of the temporary storage tank Ⅰ7 is connected to the washing water outlet s of the cleaning device 1, and the outlet thereof is connected to the sewage pipe h and the reboiler Ⅱ3, and is used for storing washing water.

[0047] The upper inlet of the temporary storage tank Ⅱ8 is respectively connected to the organic solvent discharge outlet t of the cleaning device 1 and the lower outlet of the separator Ⅰ5; the lower outlet of the temporary storage tank Ⅱ8 is respectively connected to the inlet of the reboiler Ⅰ2 and the evaporation process f, and is used to store the washing organic solvent discharged from the cleaning device 1.

[0048] The inlet of the reflux tank 9 is connected to the outlet of the separator Ⅰ5 through a condenser, and its outlet is connected to the solvent receiving tank b (out-of-bounds storage tank), the upper inlet of the separator Ⅰ5, and the organic solvent elution inlet u of the cleaning device 1 through three parallel pipelines.

[0049] In the polyetheretherketone refining treatment system of the present invention, the organic solvent is preferably one of acetone and ethanol. The organic solvent inlet is a tangential feed port, which adopts a tangential feed form to keep the material in a tumbling state, increase the contact area between the solvent and the PEEK-diphenyl sulfone solid, and improve the extraction efficiency; a leaching distributor is provided in the cleaning device 1 for the leaching liquid to pass through.

[0050] The steps of refining polyetheretherketone in the polyetheretherketone refining treatment system provided by the present invention are as follows (taking acetone as an example to illustrate the organic solvent cleaning process): 1. Organic solvent cleaning process. PEEK-diphenyl sulfone solid is delivered to the cleaning device 1 through the solid feeding port k by pneumatic conveying, and fresh acetone is continuously fed into the cleaning device 1 through the tangential feeding port c, and the tangential feeding is continuously carried out to ensure that the solid material is in a tumbling state, and the PEEK-diphenyl sulfone solid is completely immersed, and the acetone extracts diphenyl sulfone; the filter cap w of the organic solvent discharge port t can intercept the PEEK solid and make the acetone and diphenyl sulfone mixture flow to the temporary storage tank Ⅱ8; the liquid material in the temporary storage tank Ⅱ8 is discharged by the material pump I, and a part of it is heated by the reboiler Ⅰ2 and forced to circulate and heat with the material in the cleaning device 1 to maintain a certain extraction temperature in the cleaning device 1, and the other part of the acetone and diphenyl sulfone mixture is intermittently extracted to the evaporation process f to recover diphenyl sulfone; the present invention controls the extraction amount of the material pump I to the evaporation process f to maintain the diphenyl sulfone content in the cleaning device 1 at a higher concentration. As the cleaning process proceeds and the extraction amount of the evaporation step f is removed, the diphenyl sulfone content in the PEEK of the cleaning device 1 continues to decrease. In the later stage of the cleaning operation, the extraction amount of the solvent in the evaporation step f can be reduced or intermittently extracted to ensure that the diphenyl sulfone content in the acetone is maintained at a higher concentration.

[0051] In order to ensure the mixed cleaning effect of the solvent and PEEK, the present invention, on the one hand, controls the opening of the material pump I of the temporary storage tank II8 to promote the mixing degree of the materials in the cleaning device 1, and on the other hand, adopts the tangential feeding form to provide the material tumbling state.

[0052] In order to achieve a better extraction effect, high-purity nitrogen gas may be blown into the inert gas inlet d of the cleaning device 1 to promote the tumbling of PEEK, thereby making it more conducive for the diphenyl sulfone embedded between PEEK to be dissolved by the solvent.

[0053] When the number of extraction to evaporation steps f reaches 5-8 times, enter the next step.

[0054] 2. Organic solvent elution process. At this time, the residual diphenyl sulfone content in PEEK is relatively low, and fresh solvent acetone enters through the organic solvent elution inlet u of the cleaning device 1. Acetone continuously elutes PEEK through the elution distributor. The leached acetone and diphenyl sulfone mixture flows to the temporary storage tank II8, and then is transferred to the reboiler I2 through the material pump I for heating and vaporization. The vaporized acetone enters the gas-liquid separation section at the bottom of the separator I5 to achieve gas-liquid separation, and the liquid phase is partially extracted to the temporary storage tank II8. The gas phase enters the packing of the separator I5, and flows to the solvent reflux tank 9 after condensation by the condenser. The cooled solvent in the reflux tank 9 is partially returned to the top of the tower as reflux liquid through the pump, and partially returned to the cleaning device 1 to elute PEEK (at this time, the solvent used for elution after treatment by the separator I5 does not contain diphenyl sulfone), and the remaining part is extracted to the solvent receiving tank b; with the continuous operation of the above operation, acetone continuously circulates to extract diphenyl sulfone, the diphenyl sulfone content in PEEK continues to decrease, and the diphenyl sulfone content in the temporary storage tank II8 continues to increase. When the diphenyl sulfone content in the temporary storage tank II 8 increases to a certain concentration, the solvent-diphenyl sulfone mixture can be intermittently withdrawn to enter the evaporation step f. In order to ensure the liquid holding capacity of the system, after the mixed liquid of solvent and diphenyl sulfone is withdrawn, fresh organic solvent needs to be appropriately added. When the diphenyl sulfone content in PEEK is reduced to the required content (500ppm), the organic solvent elution process can be stopped.

[0055] After completing the cleaning process of process one and process two, proceed to the next process.

[0056] 3. A gaseous solvent is used for the steam washing process, that is, fresh acetone is vaporized in the reboiler III 4 and then enters the organic solvent steam distributor at the bottom of the cleaning device 1 in a gaseous form. The gas phase passes through the material upward, bringing out a small amount of diphenyl sulfone remaining between the PEEK particles, and then flows out from the gas phase outlet x of the cleaning device 1 and enters the separator I 5. The subsequent operation is consistent with the organic solvent elution process. Part of the condensed solvent is refluxed, and part is extracted and returned to the fresh solvent raw material tank for application.

[0057] After the above three steps are completed, PEEK no longer contains diphenyl sulfone, and ultrapure water washing solvent and fluoride salt operation are carried out at this time.

[0058] 4. Pure water elution process. Ultrapure water continuously enters from the pure water inlet q of the cleaning device 1, and elutes the PEEK crude product after passing through the elution distributor. The residual solvent acetone and a small amount of sodium fluoride in the PEEK crude product are dissolved in water, and the washing water containing the solvent acetone and sodium fluoride flows from the washing water outlet s to the temporary storage tank Ⅰ7. The washing water is transferred to the reboiler Ⅱ3 through the material pump for heating and heating to 80°C. The acetone in the washing water is vaporized and carries part of the water vapor into the separator Ⅱ6. In the separator Ⅱ6, the gas phase and the liquid phase are separated by the gas-liquid separation section of the separator Ⅱ6. After the gas phase enters the condenser for condensation, part of it flows back to the gas-liquid separation section, and part of it is extracted to the sewage pipe m outside the system, and the liquid phase re-enters the cleaning device 1 for circulation; when the COD in the pure water is detected to be ≤500mg / L, the acetone in the system is basically removed, and the pure water elution process is completed.

[0059] 5. Water washing and desalting process. The temperature of reboiler II3 is lowered, and the temporary storage tank I7 intermittently produces sodium fluoride aqueous solution, and fresh pure water is appropriately added. The sodium fluoride impurities are cleaned by multiple water replenishment and external washing water.

[0060] When the crude PEEK no longer contains solvent and sodium fluoride, water can be discharged from the washing water outlet s of the washer 1, and the solid outlet p at the bottom of the washer 1 is opened to allow the PEEK to be discharged to the lower pipeline by gravity and enter the next process.

[0061] Taking the single reactor as an example, the processing capacity of 1500kg of PEEK after polymerization is 10000kg, the conventional process ( Figure 1 ) It needs to be washed with organic solvent acetone 12-14 times (hereinafter calculated as 12 times), and 4m³ of acetone is consumed each time, and the batch solvent consumption is 12×4=48m³. Because the solvent contains a large amount of diphenyl sulfone in the first three times, it is directly transferred to the crystallization kettle after cleaning. The third to twelfth solvents are 36m³ in total, all of which need to be purified and recycled. Because the solvent is volatile, the high number of solvent washings also leads to solvent loss due to volatilization; the number of water washings is 10-12 times (hereinafter calculated as 10 times), and the water consumption each time is 4m³, and the total water consumption is 10×4=40m³. This part of water needs to be treated as sewage, which is very expensive.

[0062] Through experimental verification, taking 1500kg of PEEK that has been polymerized and processed by a single kettle as an example, according to the process and equipment used in the present invention, solvent washing also requires 12 times, and the average solvent consumption each time is 1.92m³ / time (4m³ of solvent is consumed each time for the first and second times, and 1.5m³ of solvent is consumed each time from the third to the twelfth time), and a total of 23m³ of solvent is required; the overall solvent can be saved by 25m³, while the energy consumption of the solvent volatilization during use and the recovery process can be saved. At the same time, the water washing process adopts a continuous water inlet and continuous drainage method, and the overall water consumption is about 25m³. According to 10 water washing calculations, the consumption each time is 2.5m³, and the overall water saving is 15m³, which not only saves water consumption, but also saves pure water storage tanks and sewage treatment costs.

Claims

1. A polyetheretherketone refining treatment system, comprising a cleaner, a reboiler I, a reboiler II, a reboiler III, a separator I, a separator II, a temporary storage tank I and a temporary storage tank II; The lower ends of the separator I and the separator II are provided with a gas-liquid separation section; The top of the cleaning device is provided with a solid feeding port, and the bottom is connected to the temporary storage tank II; A tangential feed port is provided on the side wall of the cleaning device, and the tangential feed port is connected to the outlet of the reboiler I, and an organic solvent feed pipeline is provided on the connecting pipeline; the inlet of the reboiler I is connected to the temporary storage tank II; An organic solvent vapor inlet is provided on the side wall of the cleaning device, and the organic solvent vapor inlet is connected to the reboiler III; A gas phase outlet is provided on the side wall of the cleaning device, and the gas phase outlet is connected to the separator I, and the separator I is connected to a reflux tank, and part of the organic solvent in the reflux tank is transported out, part of it is refluxed to the separator I, and part of it is returned to the cleaning device as a washing liquid; The outlet of the reboiler I is also connected to the lower part of the separator I; A pure water inlet is provided on the side wall of the cleaning device, and the bottom is connected to the temporary storage tank I, the temporary storage tank I is connected to the reboiler II, the outlet of the reboiler II is connected to the separator II, and the water phase outlet of the separator II is connected to the pure water inlet.

2. The polyetheretherketone refining treatment system according to claim 1, characterized in that: The cleaning device is provided with a leaching distributor for the leaching liquid to pass through; A steam distributor is arranged inside the cleaning device for allowing the organic solvent steam to pass through.

3. The polyetheretherketone refining treatment system according to claim 2, characterized in that: An organic solvent washing inlet is provided on the side wall of the cleaning device; One end of the organic solvent elution inlet is connected to the separator I, and the other end is connected to the elution distributor.

4. A polyetheretherketone refining treatment method, comprising an organic solvent cleaning step, an organic solvent eluting step, an organic solvent steam washing step and a water washing step carried out in the polyetheretherketone refining treatment system according to any one of claims 1 to 3.

5. The method according to claim 4, characterized in that: The organic solvent cleaning steps are as follows: The organic solvent is fed into the cleaning device through the tangential feed port to completely immerse the material for cleaning; the mixed liquid after cleaning flows into the temporary storage tank II, a part of which passes through the reboiler I and is forced to circulate and heat with the material in the cleaning device to maintain the extraction temperature; the other part is sent to the evaporation process; when the diphenyl sulfone content in the temporary storage tank II8 increases to a specific concentration, the solvent-diphenyl sulfone mixture can be intermittently extracted to enter the evaporation process.

6. The method according to claim 4 or 5, characterized in that: The organic solvent elution step is as follows: The organic solvent enters from the organic solvent elution inlet at the top of the scrubber for elution, and the mixed liquid after elution flows into the temporary storage tank II, and then is heated and vaporized by the reboiler I. The vaporized organic solvent enters the gas-liquid separation section at the bottom of the separator I to achieve gas-liquid separation. The gas phase part enters the packing of the separator I, and after condensation, it flows into the reflux tank. One part is output to the outside, one part is refluxed to the separator I, and one part is returned to the scrubber as elution liquid. The liquid phase part is extracted into the temporary storage tank II. When the diphenyl sulfone content in the temporary storage tank II8 increases to a specific concentration, the solvent-diphenyl sulfone mixture can be intermittently extracted to enter the evaporation process.

7. The method according to any one of claims 4 to 6, characterized in that: The organic solvent steam washing steps are as follows: After being vaporized in the reboiler III, the organic solvent enters the steam distributor in the scrubber from the organic solvent steam inlet, passes upward through the material for washing, flows out from the organic solvent gas phase outlet into the separator I, and flows into the reflux tank after condensation, with a portion being output externally, a portion being refluxed to the separator I, and a portion being returned to the scrubber as eluent.

8. The method according to any one of claims 4 to 7, characterized in that: The steps of the washing are as follows: Water is input into the cleaning device through the pure water inlet to wash the material; the mixed liquid after washing flows into the temporary storage tank I, and is heated and heated by the reboiler II. After heating, the organic solvent in the water is vaporized, and the vaporized organic solvent enters the separator II. The solvent enters the separator II as a gas phase, and after condensation, it refluxes to the gas-liquid separation section and is extracted outside the system. The liquid phase in the separator II refluxes to the cleaning device.

9. The method according to claim 8, characterized in that: Rinse the material with water.

10. The method according to any one of claims 4 to 9, characterized in that: The method also includes a water washing and desalting step: the temperature of the reboiler II is lowered, the temporary storage tank I intermittently produces a sodium fluoride aqueous solution and replenishes it with fresh pure water, and the sodium fluoride impurities are cleaned by multiple water replenishments and external washing water.

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