A system for separating and purifying cyclic ester substances and its application

Abstract

The present invention relates to a separation and purification system for cyclic ester substances, which includes a countercurrent jet cooling unit for relatively jet-mixing molten cyclic ester materials with a liquid cooling medium to form a solid-liquid mixed slurry; and a rotary purification treatment unit coupled with the countercurrent jet cooling unit for purifying the solid-liquid mixed slurry to obtain refined cyclic ester materials. This system utilizes the relative jet of the cooling medium and the molten material, enabling the hot molten material and the cold cooling medium to collide and mix with each other. The molten material is rapidly cooled to form a solid-liquid mixed slurry. Subsequently, the solid-liquid mixed slurry undergoes a "one-stop" purification treatment operation, which can achieve continuous and stable production, and recycle and reuse the filtered filtrate, washing liquid used for washing, etc. This not only reduces the number of equipment and economic costs, but also effectively shortens the process operation flow and improves efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical engineering, and particularly relates to a separation and purification system for cyclic ester substances and its application. Background Art

[0002] Cyclic esters (such as lactide, glycolide, etc.) can be used as monomers for preparing degradable materials (such as poly(lactide), poly(glycolide), etc.). Therefore, the preparation processes of cyclic esters have attracted more and more extensive attention. Usually, in the process steps of preparing cyclic esters, it is necessary to separate and purify the crude cyclic esters (for example, crude glycolide, crude lactide, etc.) to remove the impurities therein, and then use them for subsequent refining and purification processes. Currently, for the separation and purification of cyclic ester substances, steps such as washing, filtration, and drying are usually required to remove the impurities therein.

[0003] However, in order to implement the above steps, it is usually necessary to jointly use multiple sets of process devices such as washing kettles / washing tanks, vacuum centrifuges, dryers / drying kettles, etc. Between these devices, it is usually necessary to arrange auxiliary equipment such as transfer pumps, blowers, and their matching pipelines, pipe fittings, valves, etc. The process flow is long, there are many redundant operations, solvent leakage is likely to occur, and there are relatively large potential safety hazards. In addition, these devices themselves are large in volume, occupy a large area, consume high energy, and the more devices used, the greater the risk brought by the device failure rate, and it is difficult to ensure the long-term continuous and stable operation of the process production. Summary of the Invention

[0004] One of the purposes of the present invention is to provide a separation and purification system for cyclic ester substances in order to solve the above problems existing in the separation and purification of cyclic ester substances.

[0005] Another purpose of the present invention is to provide the application of the separation and purification system.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A separation and purification system for cyclic ester substances, comprising:

[0008] A countercurrent jet cooling unit, which is used to relatively jet and mix the molten cyclic ester material with the liquid cooling medium to form a solid-liquid mixed slurry; and

[0009] A rotary purification treatment unit, which is coupled with the countercurrent jet cooling unit and is used to process the solid-liquid mixed slurry to obtain a refined cyclic ester material.

[0010] The treatment includes filtration and at least one washing and at least one drying after filtration.

[0011] Further, the at least one washing and the at least one drying can be arbitrarily combined according to actual needs. For example, but not limited to the following forms: after filtration, one washing can be carried out first, and then one drying; or, after filtration, three washings can be carried out first, and then two dryings; or, after filtration, one drying can be carried out first, then one washing, then one drying, then one washing, and finally one drying, etc.

[0012] This system couples a convective jet cooling unit with a rotary purification processing unit. In the convective jet cooling unit, by the relative jetting of a cooling medium and a molten material (i.e., molten cyclic ester substances), the hot molten material collides and mixes with the cold cooling medium, and the molten material is rapidly cooled. Under the stirring action, it is broken into fine granular forms and forms a solid-liquid mixed slurry with the cooling medium.

[0013] Subsequently, the solid-liquid mixed slurry is transported to the rotary purification processing unit for "one-stop" purification processing operations, realizing continuous and stable production, and recycling the filtered filtrate, washing liquid used for washing, etc.

[0014] Compared with the existing conventional batch production, this system not only reduces the number of process equipment, saves production land, and reduces economic costs, but also can effectively shorten the process operation flow, greatly improve work efficiency, has low energy consumption, and can achieve low-carbon production.

[0015] As an implementation scheme, the convective jet cooling unit includes a cooling and stirring kettle. Inside the cooling and stirring kettle, there are respectively provided a first convective jetting mechanism for jetting the molten cyclic ester material and a second convective jetting mechanism for jetting the liquid cooling medium. The first convective jetting mechanism and the second convective jetting mechanism are arranged oppositely.

[0016] As an implementation scheme, the first convective jetting mechanism includes an annular pipe arranged on the inner wall of the cooling and stirring kettle, and the second convective jetting mechanism includes an annular pipe arranged on the inner wall of the cooling and stirring kettle and arranged opposite to the annular pipe of the first convective jetting mechanism. At least one nozzle is provided on each annular pipe.

[0017] As an implementation scheme, the nozzles on the annular pipe of the first convective jetting mechanism and the nozzles on the annular pipe of the second convective jetting mechanism are in one-to-one correspondence and arranged oppositely.

[0018] As an implementation scheme, the nozzles are oriented towards the central axis of the cooling and stirring kettle and are inclined downward. The included angle between the jetting direction of the nozzles and the central axis of the cooling and stirring kettle is 30 - 60°.

[0019] As an implementation scheme, the annular tube has two blind ends, a feed port is provided on the tube body between the two blind ends, and the nozzle is arranged on the tube body between the two blind ends;

[0020] Alternatively, the annular tube has a feed inlet and a blind end, and the nozzle is arranged on the tube body between the feed inlet and the blind end.

[0021] As an embodiment, the convection injection mechanism is provided with one or more;

[0022] When multiple arrangements are adopted, each countercurrent injection mechanism is arranged in the cooling stirring tank in parallel and at intervals along the axial direction of the cooling stirring tank.

[0023] As an implementation scheme, the first convection injection mechanism is connected to a material supply mechanism, and the second convection injection mechanism is connected to a cooling medium supply mechanism.

[0024] As an embodiment, the material supply mechanism comprises a melting stirring kettle, which is connected to the feed port of the first convection injection mechanism through a material supply pipeline;

[0025] The cooling medium supply mechanism comprises a cooling medium storage tank, which is connected to the feed port of the second convection injection mechanism through a cooling medium supply pipeline, and a cooler is also provided on the cooling medium supply pipeline.

[0026] In one form, a heating jacket may be provided on the outside of the melting stirring tank to heat the melting stirring tank to melt the material in the melting stirring tank.

[0027] As an embodiment, a melt metering pump is provided on the material supply pipeline, and a liquid metering pump is provided on the cooling medium supply pipeline.

[0028] As an implementation scheme, a discharge port is provided at the bottom of the cooling stirring tank, and the discharge port is connected to the rotary purification processing unit through a slurry conveying pipeline.

[0029] In one form, a cooling jacket may be provided on the outside of the cooling stirring tank, and a cooling medium is introduced into the cooling jacket to reduce the temperature in the cooling stirring tank and maintain the temperature in the cooling stirring tank at a relatively low temperature.

[0030] As an implementation scheme, a solenoid valve is provided at the discharge port, and the discharge port is a funnel-shaped or trumpet-shaped discharge port.

[0031] As an implementation scheme, a buffer tank is also provided on the slurry conveying pipeline.

[0032] As an embodiment, the rotary purification treatment unit comprises:

[0033] Shell;

[0034] A drum, rotatably disposed within the shell about the axis of the shell, an annular chamber being formed between the drum and the shell;

[0035] A plurality of seals, disposed at intervals along the circumferential direction of the shell on the inner wall of the shell and extending axially along the shell, for dividing the annular chamber to form a plurality of independently sealed chamber regions, the plurality of independently sealed chamber regions being divided into a plurality of processing sections;

[0036] A plurality of partition chambers, disposed on the surface of the drum for accommodating materials to be processed;

[0037] A filtering member, provided at the bottom of each partition chamber;

[0038] A plurality of flow-through pipes, passing through the inner cavity of the drum and communicating with the corresponding partition chambers;

[0039] The plurality of processing sections include a filtering section, at least one washing section and at least one drying section, which are arranged downstream of the filtering section along the rotation direction of the drum and can be arbitrarily combined, and a discharging and flushing section. For example but not limited to the following forms, taking the rotation direction of the drum as a reference, after the filtering section, one washing section can be set first, then one drying section, and finally the discharging and flushing section; or, after the filtering section, three washing sections can be set first, then two drying sections, and finally the discharging and flushing section; or, after the filtering section, one drying section can be set first, then one washing section, then one drying section, then one washing section, then one drying section, and finally the discharging and flushing section, and so on.

[0040] As an implementation scheme, the filtering section is provided with a slurry feed port, and the slurry feed port is connected to the discharge port of the convection jet cooling unit through a slurry conveying pipeline.

[0041] As an implementation scheme, a washing liquid inlet is provided in the chamber region of the washing section, and the washing liquid inlet is connected to an external washing liquid storage tank through a pipeline.

[0042] Preferably, the slurry feed port and the washing liquid inlet can be set at the starting point of the corresponding chamber region or at a position close to the starting point.

[0043] Preferably, the seal is configured to contact the drum and divide the annular chamber into a plurality of chamber regions, and the seal is adapted to seal each chamber region relative to other chamber regions.

[0044] As an implementation, the drying section adopts a pressurized drying section or a vacuum drying section.

[0045] If a pressurized drying section is adopted, a drying gas inlet is provided in the cavity area of the drying section. The drying gas inlet is connected to an external drying gas source through a pipeline (a heater may be provided on the pipeline). In the working state, the drying gas (for example, an inert gas or a heated inert gas) from the external drying gas source is injected into the cavity area of the drying section at a certain pressure (for example, 0.3 - 0.6 MPa) through the drying gas inlet, and the material to be dried in the cavity area is dried.

[0046] If a vacuum drying section is adopted, there is no need to set a drying gas inlet in the cavity area of the drying section. In the working state, a vacuum pump can be used to evacuate the cavity area through a flow pipe to perform vacuum drying on the material to be dried in the cavity area.

[0047] As an implementation, the filtering section, the washing section, and the drying section are designed to respectively include one cavity area or multiple cavity areas. For example, the filtering section, the washing section, and the drying section can all be designed to respectively include one cavity area, or the filtering section, the washing section, and the drying section can all be designed to respectively include two cavity areas, or the filtering section can be designed to include one cavity area, the washing section can be designed to include three cavity areas, and the drying section can be designed to include two cavity areas.

[0048] As an implementation, the long side of the partition chamber is arranged along the axial direction of the drum, and the wide side is arranged along the circumferential direction of the drum;

[0049] The long side of the partition chamber is provided with a protrusion protruding towards the outside of the partition chamber and / or towards the inside of the partition chamber. The protrusion makes the partial width or the entire width of the partition chamber along the circumferential direction of the drum have a gradual change.

[0050] In this way, in the working state, when the partition chamber rotates with the drum and enters a new cavity area, the partition chamber is slowly opened (or opened) relative to the new cavity area. That is, when the partition chamber enters a new cavity area, first a small part of the partition chamber is exposed to the new cavity area, and then over time, the rest of the partition chamber will gradually be exposed to the new cavity area. This can reduce the pressure fluctuation when the partition chamber enters a new cavity area (for example, from the cavity area of the filtering section to the cavity area of the washing section), allow the fluid in the new cavity area to enter the partition chamber faster, effectively improve the processing capacity of the new cavity area. In addition, due to the reduction of pressure fluctuation, it is beneficial to prevent the lateral movement of the filtering component in the partition chamber, reduce the damage to the filtering component, and is beneficial to extending the service life of the filtering component.

[0051] As an implementation, the protrusion is a partial protrusion provided on the long side of the partition chamber, and this partial protrusion makes the partial width of the partition chamber along the circumferential direction of the drum have a gradual change; in such a case, the protrusion can be designed as one, which can be provided at the middle position of the long side of the partition chamber; or the protrusion can be designed as multiple, and they can be centrally or relatively dispersedly provided on the long side of the partition chamber.

[0052] Alternatively, the protrusion is a full protrusion, which itself forms the long side of the partition chamber, and this full protrusion makes the full width of the partition chamber along the circumferential direction of the drum have a gradual change.

[0053] As an implementation, the protrusion is configured as an arc-shaped protrusion, and a reinforcing rib is provided between the protrusions of two adjacent partition chambers.

[0054] As an implementation, a flow-through hole is provided at the bottom of the partition chamber, and a plurality of flow-through pipes are provided in total. One end of each flow-through pipe passes through the inner cavity of the drum and is connected to the flow-through hole at the bottom of the corresponding partition chamber, and the other end is connected to a header that is located in the inner cavity of the drum and fixedly connected to the drum; in the working state, the flow-through pipes rotate together with the drum and the partition chamber.

[0055] As an implementation, a through cavity is provided inside the header, the through cavity is communicated with each flow-through pipe, and the through cavity is communicated with an external recovery tank through a pipeline.

[0056] As an implementation, the filtering member includes a filter screen provided in the partition chamber and a filter cloth laid on the filter screen.

[0057] Preferably, the material of the filter screen can be selected from metals (such as stainless steel, aluminum alloy, etc.) or polymers (such as polyether ether ketone, polytetrafluoroethylene, polyvinylidene chloride, polyvinyl chloride, polypropylene, etc.). In actual application, a suitable material can be selected according to the temperature of the material to be filtered.

[0058] As an implementation, a discharge port and a flushing port are provided in the cavity area of the discharge flushing section;

[0059] A pneumatic spring shoveling mechanism is provided at the discharge port;

[0060] A plurality of flushing nozzles are provided at intervals along the direction parallel to the axis of the drum at the flushing port, and the plurality of flushing nozzles are respectively provided in one-to-one correspondence with a plurality of partition chambers along the axial direction of the drum.

[0061] As an implementation scheme, the pneumatic spring material shoveling mechanism includes a linkage rod arranged parallel to the axis of the rotary drum, a driving cylinder drivingly connected to the linkage rod, a connecting rod parallel to the linkage rod and fixedly connected to the linkage rod, shovel blade members arranged on the connecting rod at intervals and corresponding to a plurality of partition chambers along the axial direction of the rotary drum one by one, and buffer springs connected to the linkage rod and corresponding to the shovel blade members one by one.

[0062] As an implementation scheme, the connecting rod is fixedly connected to the linkage rod through rib plates.

[0063] As an implementation scheme, a plurality of rib plates are provided in total and correspond to the shovel blade members one by one.

[0064] As an implementation scheme, the shovel blade member includes a support rod fixedly connected to the connecting rod at the top and a shovel blade arranged at the bottom of the support rod.

[0065] As an implementation scheme, the long side of the side of the seal in contact with the rotary drum extends along the axial direction of the housing, and the length of the long side is not less than the axial length of the rotary drum.

[0066] As an implementation scheme, the width of the wide side of the side of the seal in contact with the rotary drum is not less than the maximum width of the partition chamber along the circumferential direction of the rotary drum.

[0067] In actual design, the seal is configured to contact the rotary drum with a relatively appropriate pressure to seal the adjacent two chamber areas from each other without affecting the normal rotation of the rotary drum in the working state.

[0068] Preferably, the seal can be made of a material with certain elasticity or toughness, such as but not limited to rubber, polyether ether ketone and other materials.

[0069] As an implementation scheme, a rotating shaft is provided along the axis of the housing in the housing, the rotary drum is fixedly connected to the rotating shaft and is rotatably arranged in the housing through the rotating shaft.

[0070] As an implementation scheme, mechanical seals are provided at the positions where the two axial ends of the housing are connected to the rotating shaft. An isolation cover is provided on the outer periphery of the mechanical seal. Air holes are provided on the isolation cover, and inert gas is filled into the isolation cover through the air holes so that the air pressure in the isolation cover is appropriately higher than the pressure inside the housing, thereby realizing the air sealing function of the isolation cover.

[0071] At the position where the housing of the rotary purification processing unit is connected to the rotating shaft, a combination of a mechanical seal and an isolation cover is adopted, which can further prevent the leakage of the internal air flow of the housing, ensure the safety of the production environment, and effectively prevent the erosion caused to other external equipment due to the leakage of the air flow, which is beneficial to improving the service life of the device.

[0072] An application of a cyclic ester separation and purification system, which is used for the separation and purification of crude cyclic esters (for example, crude glycolide, crude lactide, etc.), and includes the following steps:

[0073] Step 1): Heat and melt the crude cyclic ester to be processed, and then relatively spray and mix the molten crude cyclic ester with a liquid cooling medium through the convective jet cooling unit (b) to form a solid-liquid mixed slurry;

[0074] Step 2): Transport the solid-liquid mixed slurry to the rotary purification processing unit (a) for purification processing, and then obtain a refined cyclic ester material after discharging.

[0075] As an embodiment, the heating temperature of the crude cyclic ester to be processed is controlled at 70-150 °C;

[0076] As an embodiment, the temperature of the cooling medium is not higher than 30 °C, preferably not higher than 10 °C, and more preferably -50 °C to 10 °C.

[0077] As an embodiment, the cooling medium is selected from at least one of ester solvents, alcohol solvents, ether solvents, alcohol-ether solvents or ketone solvents.

[0078] Preferably, the ester solvent can be selected from one or more of methyl acetate, ethyl acetate or butyl acetate, the alcohol solvent can be selected from one or more of saturated monohydric alcohols or polyhydric alcohols with C1-C5, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, 1-pentanol, 2-pentanol, 3-pentanol, ethylene glycol, diethylene glycol or 1,2-propanediol, etc., the ether solvent can be selected from one or two of dimethyl ether or n-butyl ether, the alcohol-ether solvent can be selected from one or more of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether or ethylene glycol dimethyl ether, and the ketone solvent can be selected from one or more of acetone, cyclohexanone or methyl isobutyl ketone.

[0079] As an embodiment, in the working state, the jet mass ratio of the crude cyclic ester to the cooling medium per unit time is 1:2-20.

[0080] As an implementation, in the working state, the rotary purification unit inputs the solid-liquid mixed slurry at a pressure of 0.3 - 0.6 MPa, with a temperature not higher than 60°C, preferably not higher than 30°C.

[0081] As an implementation, in the working state, the washing section of the rotary purification unit inputs the washing liquid at a pressure of 0.3 - 0.6 MPa, and the amount of the washing liquid is 1.2 - 4 times the mass of the filter cake to be washed.

[0082] As an implementation, the washing liquid can be selected from at least one of ester solvents, alcohol solvents, ether solvents, alcohol-ether solvents, or ketone solvents.

[0083] Preferably, the ester solvent can be selected from one or more of methyl acetate, ethyl acetate, or butyl acetate; the alcohol solvent can be selected from one or more of saturated monohydric alcohols or polyhydric alcohols with C1 - C5, such as one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, 1-pentanol, 2-pentanol, 3-pentanol, ethylene glycol, diethylene glycol, or 1,2-propanediol, etc.; the ether solvent can be selected from one or two of dimethyl ether or n-butyl ether; the alcohol-ether solvent can be selected from one or more of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, or ethylene glycol dimethyl ether; the ketone solvent can be selected from one or more of acetone, cyclohexanone, or methyl isobutyl ketone.

[0084] Compared with the prior art, the present invention has the following beneficial effects:

[0085] 1) This system couples the convective jet cooling unit with the rotary purification unit. In the convective jet cooling unit, by the relative jet of the cooling medium and the molten material (i.e., cyclic ester substances), the hot molten material and the cold cooling medium collide and mix with each other. The original molten material is quickly cooled and is broken into fine granular forms under the action of the stirring paddle, forming a solid-liquid mixed slurry with the cooling medium. Subsequently, the solid-liquid mixed slurry is transported to the rotary purification unit for "one-stop" purification operation, which can achieve continuous and stable production, and can recycle and reuse the filtered filtrate, the washing liquid used for washing, etc. Compared with the existing conventional batch production, this system not only reduces the number of process equipment, saves production land, and reduces economic costs, but also can effectively shorten the process operation flow, greatly improve work efficiency, has low energy consumption, and can achieve low-carbon production;

[0086] 2) In this system, the cooling medium used in the convection jet cooling unit can not only cool the molten material (such as molten crude glycolide), but also serve as a good transportation medium to convey the material. This is not only conducive to reducing the residence time of the hot molten material (such as molten crude glycolide) at high temperature, inhibiting or reducing the degree of self-polymerization of cyclic esters (such as glycolide), but also effectively avoiding the phenomenon that the hot molten material blocks the pipeline due to deterioration and solidification during pipeline transportation, which is conducive to ensuring the continuity of production;

[0087] 3) In the structural design of the partition chambers on the surface of the drum of the rotary purification unit in this system, the long sides of the partition chambers form protrusions protruding towards the outside of the partition chambers and / or towards the inside of the partition chambers, so that the partial width or the entire width of the partition chambers along the circumferential direction of the drum has graduality. In this way, when the partition chambers enter a new chamber area with the rotation of the drum during the working state, the partition chambers are slowly opened (or opened) relative to the new chamber area, that is, when the partition chambers enter a new chamber area, first a small part of the partition chambers is exposed to the new chamber area, and then as time goes by, the rest of the partition chambers will gradually be exposed to the new chamber area. This can reduce the pressure fluctuation when the partition chambers enter a new chamber area (such as from the chamber area of the filtration section to the chamber area of the washing section), allow the fluid in the new chamber area to enter the partition chambers faster, effectively improve the processing capacity of the new chamber area. In addition, due to the reduction of pressure fluctuation, it is conducive to preventing the lateral movement of the filtering components in the partition chambers, reducing the damage to the filtering components, and prolonging the service life of the filtering components;

[0088] 4) In this system, at the position where the housing of the rotary purification unit is connected to the rotating shaft, a combination of mechanical seal and isolation cover is adopted, which can further prevent the leakage of the internal air flow of the housing, ensure the safety of the production environment, and effectively prevent the erosion caused to other external equipment by the leakage of air flow, which is conducive to improving the service life of the device. Description of the Drawings

[0089] Figure 1-1 Schematic structural diagram of the separation and purification system in Example 1 (the drying section is pressurized);

[0090] Figure 1-2 Schematic structural diagram of the separation and purification system in Example 2 (the drying section is pressurized);

[0091] Figure 2-1 Schematic structural diagram of the separation and purification system in Example 3 (the drying section is vacuum);

[0092] Figure 2-2 Schematic structural diagram of the separation and purification system in Example 4 (the drying section is vacuum);

[0093] Figure 2-3 Schematic structural diagram of the separation and purification system in Example 5 (the drying section is a vacuum type);

[0094] Figure 3-1 Schematic diagram of an annular pipe with two blind ends;

[0095] Figure 3-2 Schematic diagram of an annular pipe with one blind end;

[0096] Figure 4-1 Specific schematic diagram of a partition chamber with a single local outer protrusion;

[0097] Figure 4-2 Specific schematic diagram of a partition chamber with multiple local outer protrusions;

[0098] Figure 4-3 Specific schematic diagram of a partition chamber with all outer protrusions;

[0099] Figure 4-4 Specific schematic diagram of a partition chamber with all inner protrusions;

[0100] Figure 4-5 Schematic diagram of a partition chamber provided with a filter screen;

[0101] Figure 5 Schematic connection structure diagram of each partition chamber and flow-through pipe in the vacuum drying section;

[0102] Figure 6 Schematic structural diagram of a pneumatic spring shoveling mechanism;

[0103] Figure 7 Schematic connection structure diagram of the housing and both ends of the rotating shaft;

[0104] Reference numerals in the figure:

[0105] a - Rotary purification treatment unit;

[0106] b - Convective jet cooling unit;

[0107] A - Filtration section; B - Washing section; C - Drying section; D - Discharge flushing section;

[0108] 101 - Housing; 102 - Rotary drum; 103 - Seal; 104 - Partition chamber; 105 - Flow-through pipe; 106 - Pneumatic spring shoveling mechanism; 107 - Flushing nozzle; 108 - Slurry inlet; 109 - Washing liquid inlet; 110 - Drying gas inlet; 111 - Washing liquid storage tank; 112 - Drying gas source; 113 - Heater; 114 - Gas-liquid buffer tank; 115 - Vacuum pump; 116 - Drain valve; 117 - Drain pipe; 118 - Rotating shaft; 119 - Mechanical seal; 120 - Air hole; 121 - Isolation cover;

[0109] 1061 - Driving cylinder; 1062 - Buffer spring; 1063 - Linking rod; 1064 - Support rod; 1065 - Scraper blade; 1066 - Connecting rod; 1067 - Rib plate;

[0110] 201 - Cooling and stirring kettle; 202 - Convective injection mechanism; 203 - Melting and stirring kettle; 204 - Heating jacket; 205 - Melt metering pump; 206 - Material supply pipeline; 207 - Cooling jacket; 208 - Discharge port; 209 - Buffer tank; 210 - Slurry transfer pipeline; 211 - Cooler; 212 - Cooling medium supply pipeline; 213 - Liquid metering pump; 214 - Cooling medium storage tank;

[0111] 2021 - Annular pipe; 2022 - Nozzle; 2023 - Blind end; 2024 - Feed port;

[0112] 1041 - Long side; 1042 - Wide side; 1043 - Protrusion; 1044 - Flow - through hole; 1045 - Reinforcing rib; 1046 - Filter screen. Detailed implementation manners

[0113] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0114] Embodiment 1

[0115] As Figure 1-1 , a separation and purification system for cyclic ester substances includes a rotary purification treatment unit a and a convective injection cooling unit b. Among them, the convective injection cooling unit b is used to relatively inject and mix the molten cyclic ester material with the liquid cooling medium to form a solid - liquid mixed slurry; the rotary purification treatment unit a is coupled with the convective injection cooling unit b and is used to purify the solid - liquid mixed slurry to obtain a refined cyclic ester material.

[0116] As a specific implementation manner, as Figure 1-1 , the convective injection cooling unit b includes a cooling and stirring kettle 201. Inside the cooling and stirring kettle 201, there is a convective injection mechanism 202, including a first convective injection mechanism for injecting the molten cyclic ester material and a second convective injection mechanism for injecting the liquid cooling medium. The first convective injection mechanism and the second convective injection mechanism are arranged opposite to each other.

[0117] As a specific implementation manner, the first convective injection mechanism includes an annular pipe 2021 disposed on the inner wall of the cooling and stirring kettle 201. The second convective injection mechanism includes an annular pipe 2021 disposed on the inner wall of the cooling and stirring kettle 201 and facing the annular pipe 2021 of the first convective injection mechanism. At least one nozzle 2022 is provided on each annular pipe 2021. The nozzles 2022 on the annular pipe 2021 in the first convective injection mechanism and the nozzles 2022 on the annular pipe 2021 in the second convective injection mechanism are in one-to-one correspondence and face each other.

[0118] As a preferred implementation scheme, the nozzle 2022 faces the central axis of the cooling and stirring kettle 201 and is inclined downward. The included angle between the injection direction of the nozzle 2022 and the central axis of the cooling and stirring kettle 201 is 30 - 60°.

[0119] As Figure 3-1 , as an implementation scheme, the annular pipe 2021 has two blind ends 2023. A feed port 2024 is opened on the pipe body between the two blind ends 2023. The nozzle 2022 is provided on the pipe body between the two blind ends 2023.

[0120] As Figure 3-2 , as another implementation scheme, the annular pipe 2021 has a feed port 2024 and a blind end 2023. The nozzle 2022 is provided on the pipe body between the feed port 2024 and the blind end 2023.

[0121] One pair or more pairs of the first convective injection mechanism and the second convective injection mechanism can be provided. As set in this embodiment, two pairs are provided and are disposed in the cooling and stirring kettle 201 in parallel and spaced apart along the axial direction of the cooling and stirring kettle 201.

[0122] In this embodiment, as Figure 1-1 , the first convective injection mechanism is connected to the material supply mechanism, and the second convective injection mechanism is connected to the cooling medium supply mechanism. Among them, the material supply mechanism includes a melting and stirring kettle 203, and the melting and stirring kettle 203 is connected to the feed port 2024 of the first convective injection mechanism through a material supply pipeline 206. The cooling medium supply mechanism includes a cooling medium storage tank 214, and the cooling medium storage tank 214 is connected to the feed port 2024 of the second convective injection mechanism through a cooling medium supply pipeline 212. A cooler 211 is further provided on the cooling medium supply pipeline 212.

[0123] As an implementation scheme, a heating jacket 204 can be provided on the outside of the melting and stirring kettle 203 to heat the melting and stirring kettle 203 to melt the material in the melting and stirring kettle 203. A melt metering pump 205 is provided on the material supply pipeline 206, and a liquid metering pump 213 is provided on the cooling medium supply pipeline 212.

[0124] As an implementation, a discharge port 208 is provided at the bottom of the cooling stirring kettle 201, and the discharge port 208 is connected to the rotary purification treatment unit a through a slurry conveying pipeline 210.

[0125] As an implementation, a cooling jacket 207 may be provided on the outer side of the cooling stirring kettle 201, and a cooling medium is introduced into the cooling jacket 207 to reduce the temperature inside the cooling stirring kettle 201 and keep the temperature inside the cooling stirring kettle 201 at a relatively low level.

[0126] As an implementation, a solenoid valve is provided at the discharge port 208, and the discharge port 208 is a discharge port 208 in a funnel shape or a horn shape, and a buffer tank 209 is further provided on the slurry conveying pipeline 210.

[0127] As a specific implementation manner, such as Figure 1-1 , the rotary purification treatment unit a includes a housing 101, a drum 102, a plurality of seals 103, a plurality of partition chambers 104, a filtering member, and a plurality of flow-through pipes 105.

[0128] Among them, the drum 102 is rotatably arranged in the housing 101 around the axis of the housing 101, and an annular chamber is formed between the drum 102 and the housing 101; a plurality of seals 103 are arranged on the inner wall of the housing 101 at intervals along the circumferential direction of the housing 101 for dividing the annular chamber into a plurality of independently sealed chamber areas, and the plurality of chamber areas are sequentially divided along the rotation direction of the drum 102 into: a filtering section A, a washing section B, a drying section C, and a discharge flushing section D. The filtering section A, the washing section B, and the drying section C are designed to respectively include one chamber area or a plurality of chamber areas, and in this embodiment, the filtering section A, the washing section B, and the drying section C are designed to respectively include one chamber area.

[0129] The seal 103 is configured to be in contact with the drum 102 and divide the annular chamber into a plurality of chamber areas, and the seal 103 is adapted to seal each chamber area relative to other chamber areas.

[0130] As an implementation, the long side of the side of the seal 103 in contact with the drum 102 extends along the axial direction of the housing 101, and the length of the long side is not less than the axial length of the drum 102.

[0131] As an implementation, the width of the wide side of the side of the seal 103 in contact with the drum 102 is not less than the maximum width of the partition chamber 104 along the circumferential direction of the drum 102.

[0132] In actual design, the seal 103 is configured to contact the drum 102 with a relatively appropriate pressure to seal the adjacent two chamber areas from each other, but does not affect the normal rotation of the drum 102 in the working state.

[0133] Preferably, the seal 103 can be made of a material with certain elasticity or toughness, such as but not limited to rubber, polyether ether ketone and other materials.

[0134] A plurality of partition chambers 104 are arranged on the surface of the drum 102 for accommodating materials to be processed; a filtering member is provided at the bottom of each partition chamber 104; a plurality of flow-through pipes 105 are arranged in the inner cavity of the drum 102 and communicated with the corresponding partition chambers 104.

[0135] Among them, a slurry feed port 108 is provided in the filtration section A, and the slurry feed port 108 is connected to the discharge port 208 of the countercurrent spray cooling unit b through a slurry delivery pipeline 210; a washing liquid inlet 109 is provided in the chamber area of the washing section B, and the washing liquid inlet 109 is connected to an external washing liquid storage tank 111 through a pipeline.

[0136] As a preferred embodiment, the slurry feed port 108 and the washing liquid inlet 109 can be arranged at the starting point of the corresponding chamber area or a position close to the starting point.

[0137] In this embodiment, the drying section C is a pressurized drying section. A drying gas inlet 110 is provided in the chamber area of the drying section C. The drying gas inlet 110 is connected to an external drying gas source 112 through a pipeline (a heater 113 can be provided on this pipeline). In the working state, the drying gas (for example, an inert gas or a heated inert gas) from the external drying gas source 112 is injected into the chamber area of the drying section C at a certain pressure (for example, 0.3 - 0.6 MPa) through the drying gas inlet 110, and the material to be dried in this chamber area is dried.

[0138] In this embodiment, the long side 1041 of the partition chamber 104 is arranged along the axial direction of the drum 102, and the wide side 1042 is arranged along the circumferential direction of the drum 102. The long side 1041 of the partition chamber 104 is provided with a protrusion 1043 protruding outward and / or inward from the partition chamber 104. The protrusion 1043 makes the partial width or the entire width of the partition chamber 104 along the circumferential direction of the drum 102 have a gradual change. The advantage of such a design is that when the partition chamber rotates with the drum and enters a new chamber area during the working state, the partition chamber opens (or is opened) slowly relative to the new chamber area. That is, when the partition chamber enters a new chamber area, first a small part of the partition chamber is exposed to the new chamber area, and then as time goes by, the rest of the partition chamber will gradually be exposed to the new chamber area. This can reduce the pressure fluctuation when the partition chamber enters a new chamber area (for example, from the chamber area of the filtration section to the chamber area of the washing section), allow the fluid in the new chamber area to enter the partition chamber faster, effectively improve the processing capacity of the new chamber area. In addition, due to the reduction of the pressure fluctuation, it is beneficial to prevent the lateral movement of the filter element in the partition chamber, reduce the damage to the filter element, and is beneficial to prolong the service life of the filter element.

[0139] In this embodiment, the partition chamber can be designed in various forms such as Figures 4-1 to 4-4 . The protrusion 1043 is a local protrusion 1043 provided on the long side 1041 of the partition chamber 104. The local protrusion 1043 makes the partial width of the partition chamber 104 along the circumferential direction of the drum 102 have a gradual change; for such a situation, the protrusion 1043 can be designed as one, and it can be provided at the middle position of the long side 1041 of the partition chamber 104 (such as Figure 4-1 ); or the protrusion 1043 can be designed as multiple (such as Figure 4-2 ), and they can be arranged on the long side 1041 of the partition chamber 104 in a concentrated or relatively dispersed manner, or the protrusion 1043 is the entire protrusion 1043, and it itself forms the long side 1041 of the partition chamber 104. The entire protrusion 1043 makes the entire width of the partition chamber 104 along the circumferential direction of the drum 102 have a gradual change. The protrusion is configured as an arc-shaped protrusion, protruding outward from the partition chamber (such as Figure 4-3 ), or protruding inward from the partition chamber (such as Figure 4-4 ). A reinforcing rib 1045 is provided between the protrusions of two adjacent partition chambers 104 to increase the strength.

[0140] Such as Figure 4-5 , the filter element includes a filter mesh 1046 arranged in the partition chamber 104 and a filter cloth laid on the filter mesh 1046. Preferably, the material of the filter mesh 1046 can be selected from metals such as stainless steel, aluminum alloy, etc. or polymers such as polyether ether ketone, polytetrafluoroethylene, polyvinylidene chloride, polyvinyl chloride, polypropylene, etc. In actual application, the appropriate material can be selected according to the temperature of the material to be filtered.

[0141] In addition, a flow hole 1044 is opened at the bottom of the compartment 104, one end of the flow tube 105 passes through the inner cavity of the drum 102 and is connected to the flow hole 1044 at the bottom of the corresponding compartment 104, and the other end is connected to the bundling head located in the inner cavity of the drum 102 and fixedly connected to the drum 102.

[0142] In this embodiment, the cavity area of ​​the discharge and flushing section D is provided with a discharge port and a flushing port. A pneumatic spring shoveling mechanism 106 is provided at the discharge port, and a plurality of flushing nozzles 107 are spaced apart at the flushing port along the axial direction parallel to the drum 102. The plurality of flushing nozzles 107 are respectively arranged in one-to-one correspondence with the plurality of compartment chambers 104 along the axial direction of the drum 102.

[0143] like Figure 6 As shown, the pneumatic spring shoveling mechanism 106 includes a linkage rod 1063 arranged parallel to the axis of the drum 102, a driving cylinder 1061 connected to the linkage rod 1063, a connecting rod 1066 parallel to the linkage rod 1063 and fixedly connected to the linkage rod 1063, a shovel blade 1065 component arranged on the connecting rod 1066 at intervals and corresponding to a plurality of compartment chambers 104 along the axial direction of the drum 102, and a connecting rod 1066 connected to the linkage rod 1063 and connected to the shovel blade 1065 component. The buffer springs 1062 are arranged one by one in the blade 1065 component, and the blade 1065 is installed on the connecting rod 1066 through the support rod 1064. The connecting rod 1066 is fixedly connected to the linkage rod 1063 through the rib 1067. There are a plurality of ribs 1067, which are arranged one by one in correspondence with the blade 1065 components. The blade 1065 component includes a support rod 1064 fixedly connected to the connecting rod 1066 at the top, and a blade 1065 arranged at the bottom of the support rod 1064.

[0144] As an implementation scheme, Figure 7 A rotating shaft 118 is provided in the housing 101 along the axis of the housing 101, and the rotating drum 102 is fixedly connected to the rotating shaft 118 and rotatably arranged in the housing 101 through the rotating shaft 118. Mechanical seals 119 are provided at the positions where the two axial ends of the housing 101 are connected to the rotating shaft 118, and an isolation cover 121 is provided on the outer periphery of the mechanical seal 119. The isolation cover 121 is provided with air holes 120, and inert gas is filled into the isolation cover 121 through the air holes 120, so that the air pressure in the isolation cover 121 is appropriately higher than the pressure inside the housing 101, thereby realizing the air sealing effect of the isolation cover 121.

[0145] The specific working principle of this system is as follows:

[0146] Add the material to be processed into the melting and stirring kettle 203, heat to melt the material, and then use the melt metering pump 205 to transport the molten material to a loop pipe 2021 of the convective injection mechanism 202 arranged in the cooling and stirring kettle 201. At the same time, the cooling medium in the cooling medium storage tank 214 is cooled by the cooler 211 on the cooling medium supply pipeline 212 under the action of the liquid metering pump 213 and then transported to another loop pipe 2021 of the convective injection mechanism 202. The convective injection mechanism 202 injects the molten material and the cooling medium towards each other, and the hot molten material collides with the cold cooling medium and mixes together. The original molten material is quickly cooled and broken into granular form under the action of the stirring paddle, forming a solid-liquid mixed slurry with the cooling medium (the solid phase therein is small granular solid).

[0147] Subsequently, open the solenoid valve at the bottom discharge port of the cooling and stirring kettle 201, and transport the solid-liquid mixed slurry to the rotary purification treatment unit via the slurry transport pipeline 210 (in the working state, the drum 102 is rotating), and inject it into the cavity area of the filtration section A through the slurry inlet 108 at a certain pressure (for example, 0.3 - 0.6 MPa). The solid-liquid mixed slurry entering the cavity area will quickly fill each partition chamber 104 in the cavity area. Due to the pressure difference between the partition chamber 104 and the flow-through pipe 105, and on both sides of the filter element in the partition chamber 104 (along the circumferential direction of the drum 102), the liquid in the solid-liquid mixed slurry filled into the partition chamber 104 is forced to pass through the filter element, enter the flow-through pipe through the flow-through holes, and be discharged by the flow-through pipe 105, while the solid components in the solid-liquid mixed slurry are retained on the filter element in the form of a filter cake.

[0148] As the drum 102 rotates, the partition chamber 104 loaded with the filter cake enters the cavity area of the washing section B. The washing liquid is injected into the cavity area of the washing section B through the washing liquid inlet 109 at a certain pressure (for example, 0.3 - 0.6 MPa), and is distributed to each partition chamber 104 in this cavity area at this time, and the filter cake on the filter element in the partition chamber 104 is washed. The impurities in the filter cake are washed away, and the washing liquid carries the impurities and enters the flow-through pipe 105 through the flow-through holes and is discharged by the flow-through pipe 105.

[0149] The rotary drum 102 continues to rotate, and the partition chamber 104 loaded with the washed filter cake enters the chamber area of the drying section C (taking the pressurized drying section C as an example). The drying gas (for example, inert gas or heated inert gas) is injected into the chamber area of the drying section C at a certain pressure (for example, 0.3 - 0.6 MPa) through the drying gas inlet, and is distributed to each partition chamber 104 in the chamber area at this time, and dries the filter cake on the filter element in the partition chamber 104. The drying gas passes through the filter cake and takes out the moisture in the filter cake, enters the flow-through pipe 105 through the flow-through holes, and is discharged from the flow-through pipe 105.

[0150] The rotary drum 102 continues to rotate, and the partition chamber 104 loaded with the dried filter cake enters the discharge and flushing section D. At the discharge port of the discharge and flushing section D, under the disturbance of the pneumatic spring shoveling mechanism 106, the dried filter cake in the partition chamber 104 is broken, slides out from the partition chamber 104, and is collected. As the rotary drum 102 continues to rotate, the partition chamber 104 is rotated to the flushing port, and the flushing nozzle 107 located at the flushing port sprays the flushing liquid (such as water) into the partition chamber 104, and flushes the partition chamber 104 and the filter element therein. The flushing liquid enters the flow-through pipe 105 through the flow-through holes, and is discharged from the flow-through pipe 105; the partition chamber 104 after flushing is immediately rotated to the chamber area of the filtering section A for the next "filtering, washing, drying" cycle.

[0151] Embodiment 2

[0152] In this embodiment compared with Embodiment 1, the filtering section A of the rotary purification treatment unit includes one chamber, and the washing section B, drying section C, and discharge and flushing section D are sequentially arranged downstream of the filtering section A along the rotation direction of the rotary drum 102. Among them, the washing section B includes three chambers, and the drying section C includes two chambers, as Figure 1-2 shown, and the rest is the same as Embodiment 1.

[0153] Embodiment 3

[0154] In this embodiment compared with Embodiment 1, as Figure 2-1 shown, the drying section C is a vacuum drying section, as Figure 5 shown, a plurality of flow-through pipes 105 are provided in total. One end of each flow-through pipe 105 passes through the inner cavity of the rotary drum 102 and is connected to the flow-through hole 1044 at the bottom of the corresponding partition chamber 104, and the other end passes through the beam head fixed to the rotary drum 102 and located in the inner cavity of the rotary drum 102 and is connected to the gas-liquid buffer tank 114. An air extraction port is provided on the gas-liquid buffer tank 114, and this air extraction port is connected to the vacuum pump 115 through a pipeline. And a drain valve 116 is provided at the bottom of the gas-liquid buffer tank 114, and is connected to the drain pipe 117 through the drain valve 116.

[0155] In the working state, a vacuum pump 115 is used to evacuate the cavity area through the flow pipe 105 to perform vacuum drying on the material to be dried in the cavity area, and the rest is the same as in Embodiment 1.

[0156] Embodiment 4

[0157] Compared with Embodiment 3, in this embodiment, Figure 2-2 , the filtering section A includes a chamber, and a washing section B, a drying section C, and a discharge flushing section D are sequentially arranged downstream of the filtering section A along the rotation direction of the rotary drum 102. Among them, the washing section B includes three chambers, and the drying section C includes two chambers, and the rest is the same as in Embodiment 3.

[0158] Embodiment 5

[0159] Compared with Embodiment 3, in this embodiment, Figure 2-3 , the filtering section A includes a chamber, and a first drying section C, a first washing section B, a second drying section C, a second washing section B, a third drying section C, and a discharge flushing section D are sequentially arranged downstream of the filtering section A along the rotation direction of the rotary drum 102; among them, the first drying section C, the first washing section B, the second drying section C, the second washing section B, and the third drying section C each include a chamber, and the rest is the same as in Embodiment 3.

[0160] Embodiment 6

[0161] Apply the separation and purification system of the present invention (wherein, the drying section adopted is a pressurized drying section) to the separation and purification of crude glycolide, which specifically includes the following steps:

[0162] Step 1): Heat and melt the crude glycolide in the melting and stirring kettle 203, and then relatively inject and mix the molten crude glycolide and the liquid cooling medium through the convective injection mechanism 202 to form a solid-liquid mixed slurry in the cooling and stirring kettle 201;

[0163] Step 2): Transport the solid-liquid mixed slurry to the rotary purification treatment unit a for purification treatment, and then discharge it.

[0164] The specific process of this embodiment is as follows:

[0165] The heating temperature of the melting and stirring kettle is controlled at about 96°C;

[0166] The temperature of the cooling medium is about 0°C.

[0167] The cooling medium is a mixture of ethyl acetate and isopropanol in a mass ratio of 3:1.

[0168] The injection mass ratio of the crude glycolide to the cooling medium per unit time is about 1:10.

[0169] The temperature of the obtained solid-liquid mixed slurry is about 22 °C.

[0170] The solid-liquid mixed slurry is fed into the filtration section of the rotary purification unit at a pressure of 0.45 MPa.

[0171] The washing liquid is fed into the washing section of the rotary purification unit at a pressure of 0.45 MPa.

[0172] The washing liquid is n-butanol, and the amount of the washing liquid used is 2 times the mass of the filter cake to be washed.

[0173] Nitrogen gas at 50 °C is fed into the drying section of the rotary purification unit as the drying gas at a pressure of 0.45 MPa.

[0174] Example 7

[0175] The separation and purification system of the present invention (wherein the drying section used is a pressurized drying section) is applied to the separation and purification of crude lactide, specifically including the following steps:

[0176] Step 1): The crude lactide is heated and melted in the melting and stirring kettle 203, and then the melted crude lactide and the liquid cooling medium are sprayed and mixed relatively through the convection spraying mechanism 202 to form a solid-liquid mixed slurry in the cooling and stirring kettle 201;

[0177] Step 2): The solid-liquid mixed slurry is transported to the rotary purification unit a for purification treatment, and then it can be discharged after that.

[0178] The specific process of this example is as follows:

[0179] The heating temperature of the melting and stirring kettle is controlled to be about 110 °C;

[0180] The temperature of the cooling medium is about -15 °C.

[0181] The cooling medium is isopropyl alcohol.

[0182] The ratio of the spraying mass of the crude lactide to the cooling medium per unit time is 1:8.

[0183] The temperature of the solid-liquid mixed slurry is about 10 °C.

[0184] The solid-liquid mixed slurry is fed into the filtration section of the rotary purification unit at a pressure of 0.5 MPa.

[0185] The washing liquid is fed into the washing section of the rotary purification unit at a pressure of 0.5 MPa.

[0186] The washing liquid is ethyl acetate, and the amount of the washing liquid used is 3 times the mass of the filter cake to be washed.

[0187] Nitrogen gas at 50 °C is fed as a drying gas into the drying section of the rotary purification unit at a pressure of 0.5 MPa.

[0188] The above description of the embodiments is provided to enable those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and all improvements and modifications made by those skilled in the art without departing from the scope of the present invention according to the disclosure of the present invention should be within the protection scope of the present invention.

Claims

1. A separation and purification system for cyclic ester substances, characterized in that Comprising: A convective jet cooling unit (b) for oppositely jet - mixing the molten cyclic ester material with the liquid cooling medium to form a solid - liquid mixed slurry; And A rotary purification treatment unit (a) coupled with the convective jet cooling unit (b) for treating the solid - liquid mixed slurry to obtain a refined cyclic ester material; The rotary purification treatment unit (a) includes: A housing (101); A drum (102) rotatably disposed within the housing (101) about the axis of the housing (101), an annular chamber being formed between the drum (102) and the housing (101); A plurality of seals (103) circumferentially spaced along the inner wall of the housing (101) and axially extending along the housing (101) for dividing the annular chamber into a plurality of independently sealed chamber areas, the plurality of independently sealed chamber areas being divided into a plurality of treatment sections; A plurality of partition chambers (104) disposed on the surface of the drum (102) for accommodating the material to be treated; A filtering member provided at the bottom of each partition chamber (104); A plurality of through - flow pipes (105) passing through the inner cavity of the drum (102) and communicating with the corresponding partition chambers (104); The plurality of treatment sections include a filtering section (A), at least one washing section (B) and at least one drying section (C) which are arranged downstream of the filtering section (A) along the rotation direction of the drum (102) and can be arbitrarily combined, and a discharging and flushing section (D); The long side (1041) of the partition chamber (104) is arranged along the axial direction of the drum (102), and the wide side (1042) is arranged along the circumferential direction of the drum (102); The long side (1041) of the partition chamber (104) is provided with a protrusion (1043) protruding outward and / or inward of the partition chamber (104), and the protrusion (1043) makes a partial width or the entire width of the partition chamber (104) along the circumferential direction of the drum (102) have a gradual change; 2. The separation and purification system of a cyclic ester substance according to claim 1, characterized in that, The convective jet cooling unit (b) includes a cooling and stirring kettle (201), and a convective jet mechanism (202) is provided in the cooling and stirring kettle (201), including a first convective jet mechanism for jetting the molten cyclic ester material and a second convective jet mechanism for jetting the liquid cooling medium, and the first convective jet mechanism and the second convective jet mechanism are oppositely arranged; The first convective jet mechanism includes an annular pipe (2021) disposed on the inner wall of the cooling and stirring kettle (201), the second convective jet mechanism includes an annular pipe (2021) disposed on the inner wall of the cooling and stirring kettle (201) and facing the annular pipe (2021) of the first convective jet mechanism, and at least one nozzle (2022) is provided on each annular pipe (2021); 3. The separation and purification system for a cyclic ester substance according to claim 2, wherein, The first convective jet mechanism is connected to a material supply mechanism, and the second convective jet mechanism is connected to a cooling medium supply mechanism; The material supply mechanism comprises a melting stirring kettle (203), and the melting stirring kettle (203) is connected to the feed port of the first convection injection mechanism through a material supply pipeline (206); The cooling medium supply mechanism comprises a cooling medium storage tank (214), which is connected to a feed port of the second convection injection mechanism via a cooling medium supply pipeline (212), and a cooler (211) is also provided on the cooling medium supply pipeline (212).

4. A system for separating and purifying cyclic ester substances according to claim 1, characterized in that, The filtering section (A) is provided with a slurry feed port (108), and the slurry feed port (108) is connected to the discharge port (208) of the convection spray cooling unit (b) through a slurry conveying pipeline (210); A washing liquid inlet (109) is provided in the cavity of the washing section (B), and the washing liquid inlet (109) is connected to an external washing liquid storage tank (111) through a pipeline; The cavity area of ​​the discharge and flushing section (D) is provided with a discharge port and a flushing port; A pneumatic spring shoveling mechanism (106) is provided at the discharge port; A plurality of flushing nozzles (107) are arranged at intervals at the flushing port in a direction parallel to the axis of the rotating drum (102).

5. A system for separating and purifying cyclic ester substances according to claim 1, characterized in that, The drying section (C) is a pressurized drying section (C) or a vacuum drying section (C); The filtering section (A), the washing section (B) and the drying section (C) are designed to respectively include one cavity area or a plurality of cavity areas.

6. The separation and purification system of a cyclic ester substance according to claim 1, characterized in that, The protrusion (1043) is a local protrusion (1043) arranged on the long side (1041) of the compartment (104), and the local protrusion (1043) makes the partial width of the compartment (104) along the circumference of the drum (102) have a gradual change; Alternatively, the protrusion (1043) is the entire protrusion (1043), which itself forms the long side (1041) of the compartment (104), and the entire protrusion (1043) makes the entire width of the compartment (104) along the circumference of the drum (102) have a gradual change.

7. The separation and purification system for a cyclic ester substance according to claim 1, characterized in that, A flow hole (1044) is provided at the bottom of the compartment chamber (104), and a plurality of flow pipes (105) are provided, one end of each flow pipe (105) passes through the inner cavity of the drum (102) and is connected to the flow hole (1044) at the bottom of the corresponding compartment chamber (104), and the other end is connected to a bundling head located in the inner cavity of the drum (102) and fixedly connected to the drum (102); A through cavity is provided inside the bundling head, the through cavity is connected to each through-flow pipe (105), and the through cavity is connected to an external recovery tank through a pipeline.

8. The application of a separation and purification system for cyclic ester substances according to claim 1, characterized in that The system is used for separating and purifying crude cyclic ester substances, and comprises the following steps: Step 1): The crude cyclic ester material to be treated is heated and melted, and then the molten crude cyclic ester material and the liquid cooling medium are sprayed and mixed relative to each other through the convection spray cooling unit (b) to form a solid-liquid mixed slurry; Step 2): The solid-liquid mixed slurry is transported to the rotary purification treatment unit (a) for purification treatment, and then discharged to obtain a refined cyclic ester material.

Images