A method and equipment for extrusion dehydration of ABS powder with high water content

Abstract

The present application relates to an extrusion dehydration method and device for ABS powder with high water content, aiming to solve the problem of dehydrating ABS powder with high water content to a water content below 18wt% and avoiding plasticization in the prior art, comprising: feeding ABS powder in a first state into a first extrusion section of an extrusion mechanism, applying an extrusion pressure of 1-6MPa, and obtaining ABS powder in a third state; feeding ABS powder into a second extrusion section of an extrusion mechanism, applying an extrusion pressure of 6-12MPa, and obtaining ABS powder in a fifth state; and then crushing and dispersing ABS powder in a crushing section and a dispersing section of the extrusion mechanism to obtain ABS powder in a final state; wherein, during the extrusion dehydration process, the temperature of the ABS powder is ≤90°C, the water content of the ABS powder in the first state is ≤50wt%, the water content of the ABS powder in the third state is 20-25wt%, the water content of the ABS powder in the fifth state is 12-18wt%, and the water content of the ABS powder in the final state is 12-18wt%.

Description

Technical Field

[0001] The present application relates to the technical field of extrusion dehydration of high-water-content wet rubber powder, and in particular to a method and equipment for extrusion dehydration of high-water-content ABS powder. Background Art

[0002] ABS powder refers to the wet powder obtained by coagulation and filtration of acrylonitrile-butadiene-styrene (ABS) graft copolymer synthesized by emulsion polymerization during the production of ABS resin. This wet powder usually contains a certain proportion of water, which can be removed by wet or dry extrusion process.

[0003] In the wet extrusion process, the ABS powder single screw extrusion dehydration technology is commonly used in recent years. This technology adjusts the lead and groove depth of the single screw to form different working areas, including feeding area, conveying area, extrusion dehydration area and granulation area, to achieve continuous dehydration and molding of materials. However, this technology has some defects in practical applications.

[0004] First, during the dehydration process of single-screw extrusion, the temperature of ABS powder, especially high-water-content ABS powder, is easily raised to over 100°C due to the large extrusion force. Under such high temperature conditions, ABS powder is easily plasticized and sticks together, which not only affects the dehydration effect, but also has an adverse effect on the subsequent production process.

[0005] Secondly, the moisture in the material is discharged through the slits around the barrel during the extrusion process. However, as the equipment continues to operate, these slits are easily blocked by powder, resulting in a gradual deterioration in drainage effect. Over time, the volatility of the outlet moisture increases, which not only affects the dehydration efficiency of the material, but also has a negative impact on the stability of the downstream production process and product quality. Summary of the invention

[0006] In view of one or more of the problems existing in the prior art, the present application provides a method for extrusion dehydration of ABS powder with high water content in a first aspect, characterized in that it comprises the following steps:

[0007] The ABS powder in the first state is fed into the first extrusion section of the extrusion mechanism for extrusion, and an extrusion pressure of 1-6 MPa is applied to obtain the ABS powder in the third state;

[0008] The ABS powder in the third state is fed into the second extrusion section of the extrusion mechanism for extrusion, and an extrusion pressure of 6 to 12 MPa is applied to obtain the ABS powder in the fifth state;

[0009] The fifth state ABS powder is crushed and dispersed in the crushing section and dispersion section of the extrusion mechanism to obtain the final state ABS powder;

[0010] Among them, the maximum temperature of the ABS powder during the extrusion dehydration process does not exceed 90°C, the water content of the ABS powder in the first state does not exceed 50wt%, the water content of the ABS powder in the third state is 20-25wt%, the water content of the ABS powder in the fifth state is 12-18wt%, and the water content of the ABS powder in the final state is 12-18wt%.

[0011] By dividing the extrusion process into sections and carefully controlling the temperature and pressure in each section, it is possible to prevent the ABS powder from plasticizing while extruding and dehydrating it.

[0012] In some embodiments of the present application, the process of obtaining the fifth-state ABS powder from the first-state ABS powder includes:

[0013] Drainage is performed by at least one drainage mechanism connected laterally to the first pressing section of the pressing mechanism or to the second pressing section of the pressing mechanism.

[0014] The side drainage mechanism is connected to the side of the first extrusion section or the second extrusion section of the extrusion mechanism, and can discharge the moisture in the material laterally when the material passes through the extrusion section, thereby improving the dehydration efficiency. In the process of extrusion dehydration, the side drainage mechanism helps to keep the powder in the extrusion dehydrator, avoiding a large amount of material loss while draining and the possible blockage of the drainage channel by the powder.

[0015] In some embodiments of the present application, the step of feeding the first-state ABS powder into the first extrusion section of the extrusion mechanism for extrusion includes a front and a back two-stage processing process, and the specific execution method is as follows:

[0016] The front-end processing process is as follows: the first-state ABS powder is sent to the first extrusion front-end of the extrusion mechanism with a pressure range of 1-4 MPa and a temperature range of 25-35° C. for extrusion to obtain the second-state ABS powder;

[0017] The post-processing process is as follows: the second-state ABS powder is sent to the first extrusion post-stage of an extrusion mechanism with a pressure range of 4-6 MPa and a temperature range of 35-45° C. for extrusion to obtain the third-state ABS powder.

[0018] By dividing the first extrusion section 120 into two sections to extrude the material, the pressure and temperature during the extrusion process can be more finely controlled, thereby improving the dehydration efficiency and preventing the ABS powder from being plasticized.

[0019] In some embodiments of the present application, the step of feeding the third state ABS powder into the second extrusion section of the extrusion mechanism for extrusion includes a front and back two-stage processing process, and the specific execution method is as follows:

[0020] The front-end processing process is: sending the third-state ABS powder into the second extrusion front-end of the extrusion mechanism with a pressure range of 6-8 MPa and a temperature range of 45-60° C. for extrusion to obtain the fourth-state ABS powder;

[0021] The post-processing process is as follows: the fourth state ABS powder is sent to the second extrusion post-stage of the extrusion mechanism with a pressure range of 8-12 MPa and a temperature range of 60-85° C. for extrusion to obtain the fifth state ABS powder.

[0022] By performing segmented extrusion in the second extrusion process, each stage can be maintained within the optimal temperature and pressure range of the material. By gradually increasing the temperature and pressure, the ABS powder can be prevented from being plasticized prematurely due to excessive temperature, while allowing extrusion to release more water.

[0023] In some embodiments of the present application, before the step of feeding the first-state ABS powder into the first extrusion section of the extrusion mechanism for extrusion, the step includes:

[0024] The ABS powder in the first state is conveyed to the first extrusion section through the conveying section of the extrusion mechanism.

[0025] In some embodiments of the present application, the ABS powder in the first state is an ABS powder with a high water content, and the water content thereof is 30-40 wt %.

[0026] In some embodiments of the present application, the fifth state ABS powder is subjected to a crushing section and a dispersion section of an extrusion mechanism to obtain a final state ABS powder, which comprises:

[0027] The crushing element in the crushing section of the extrusion mechanism crushes the fifth state ABS powder to obtain the sixth state ABS powder;

[0028] The dispersing element in the dispersing section of the extrusion mechanism further crushes and disperses the ABS powder in the sixth state to obtain the ABS powder in the final state;

[0029] The second conveying element in the dispersing section of the extrusion mechanism discharges the ABS powder in the final state.

[0030] In some embodiments of the present application, the particle size of the sixth-state ABS powder does not exceed 5 mm, and the water content is 12-18 wt %.

[0031] In some embodiments of the present application, the particle size of the ABS powder in the final state does not exceed 3 mm.

[0032] The final ABS powder has a moisture content below 18wt% and a particle size within 3mm, so that in the subsequent resin production process, ABS resin with less yellowing, better gloss and higher impact strength can be produced, significantly improving the quality of the final product.

[0033] In some embodiments of the present application, the extrusion mechanism is a twin-screw extruder, and the speed of the twin-screw extruder during the extrusion dehydration process does not exceed 400 rpm. The higher the screw speed, the more intense the friction heat is generated. Therefore, if the speed of the twin-screw extruder exceeds 400 rpm, the material may be plasticized and agglomerated due to overheating, and the purpose of the invention of the present application cannot be achieved.

[0034] The second aspect of the present application provides an ABS powder extrusion and dehydration device with a high water content, which is used to complete the above method, and the device comprises: an extrusion mechanism, a drainage mechanism and a feeding mechanism;

[0035] Extrusion mechanism, used for extrusion and dehydration of ABS powder with high water content;

[0036] A drainage mechanism, used to receive the water discharged by the extrusion mechanism and discharge it from the extrusion dehydration device; and

[0037] Feeding mechanism, used to feed ABS powder with high water content into the extrusion mechanism;

[0038] Wherein, the extrusion mechanism comprises: a conveying section, an extrusion section, a crushing section and a dispersion section; the drainage mechanism is connected to the extrusion section; and the feeding mechanism is connected to the conveying section.

[0039] In some embodiments of the present application, the extrusion section is composed of a first extrusion section and a second extrusion section connected in sequence, and two side surfaces of the first extrusion section and the second extrusion section are respectively connected to the drainage mechanism.

[0040] In some embodiments of the present application, the first extrusion section includes a first extrusion front section and a first extrusion rear section, the second extrusion section includes a second extrusion front section and a second extrusion rear section, and the drainage mechanism is connected to two side surfaces of the first extrusion rear section and the second extrusion rear section, respectively.

[0041] In some embodiments of the present application, the length ratio of the first extrusion front section to the first extrusion rear section is 1:1~1:2; the length ratio of the second extrusion front section to the second extrusion rear section is 1:1~1:2.

[0042] In some embodiments of the present application, the first extrusion rear section and the second extrusion rear section include a dehydrating barrel, the dehydrating barrel is used to accommodate the extrusion screw and discharge the extrusion water from the extrusion section, the dehydrating barrel is connected to at least one of the drainage mechanisms, and the dehydrating barrel includes: a barrel and a dehydrating mechanism,

[0043] The barrel comprises a barrel wall and an extrusion cavity formed by the barrel wall, and the barrel wall is provided with at least one dehydration port;

[0044] The dewatering mechanism includes a dewatering screen and a fixing device, wherein:

[0045] The dewatering screen is arranged in the dewatering port and is matched with the cylinder wall, and the fixing device is used to fix the dewatering screen in the dewatering port;

[0046] The dewatering screen comprises at least two plates, and at least one drainage channel is formed between two adjacent plates.

[0047] In some embodiments of the present application, at least two of the plates are overlapped and fixedly connected to each other.

[0048] In some embodiments of the present application, the dewatering screen includes a plate fixing member, the plate is provided with a positioning hole, and the plate fixing member fixes and connects at least two of the plates through the positioning hole.

[0049] In some embodiments of the present application, the plate fixing member includes a clamping bolt and a positioning pin, the positioning pin is arranged in the positioning hole, the clamping bolt is inserted into the positioning hole and cooperates with the positioning pin to fix and connect at least two of the plates.

[0050] In some embodiments of the present application, the drainage channel includes a first drainage gap, a second drainage gap and a third drainage gap, the first drainage gap is located on the side of the dewatering screen close to the extrusion chamber, the first drainage gap gradually expands outward to form the second drainage gap, and finally expands to form the third drainage gap.

[0051] In some embodiments of the present application, a drainage groove is provided on the surface of the plate, and an adjacent plate of the plate covers the drainage groove to form the drainage channel;

[0052] Among them, the drainage groove includes a first drainage groove, a second drainage groove and a third drainage groove. The first drainage groove is located near the extrusion chamber. The depth of the first drainage groove is smaller than that of the third drainage groove. The bottom surface of the second drainage groove is inclined to connect the first drainage groove and the third drainage groove.

[0053] In some embodiments of the present application, lengths of at least two of the first drainage gaps along the drainage direction are kept consistent.

[0054] In some embodiments of the present application, the dewatering screen includes at least two parallel drainage channels.

[0055] In some embodiments of the present application, the fixing device includes a convex pressure plate, a boss that can be inserted into the dehydration port is formed in the middle of the convex pressure plate, a drainage port is opened in the middle of the boss, and the drainage channel is connected to the external space through the drainage port.

[0056] In some embodiments of the present application, the fixing device further includes a pressure plate locking bolt, and the convex pressure plate is fixed to the cylinder wall by the pressure plate locking bolt.

[0057] In some embodiments of the present application, the opening direction of the dehydration port is 0°~90° with respect to the horizontal radial direction of the extrusion chamber.

[0058] In some embodiments of the present application, the opening direction of the dehydration port is 0° or 90° to the horizontal radial direction of the extrusion chamber.

[0059] In some embodiments of the present application, a cooling water channel is provided in the barrel, and the cooling water channel is arranged close to the extrusion chamber.

[0060] One or more of the above embodiments of the present application have at least the following beneficial effects:

[0061] Low-temperature dehydration: This application can dehydrate ABS wet powder with a water content not exceeding 50wt% under low-temperature conditions, effectively avoiding thermal damage and plasticization problems of ABS wet powder caused by high temperature.

[0062] The dehydration effect is significant: through the method of the present application, the water content of the ABS wet powder can be reduced from no more than 50wt% to below 18wt%, and the dehydrated ABS wet powder still remains in powder form and will not be plasticized, which is beneficial to the subsequent blending and dispersion process.

[0063] Process advantages: Compared with the single-screw extrusion dehydration technology commonly used in the industry, this application will not cause the ABS wet powder to plasticize into agglomerates when the moisture content is reduced to below 18wt%, thereby ensuring the fluidity and uniformity of the material.

[0064] Improve the performance of the final product: The moisture content of the ABS powder treated by the dehydration method of the present application is below 18wt%, and the particle size is within 3mm, so that in the subsequent resin production process, ABS resin with less yellowing, better gloss and higher impact strength can be produced, significantly improving the quality of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings:

[0066] Figure 1This is a structural schematic diagram of an angle of a high-water-content ABS powder extrusion and dehydration device provided in an embodiment of the present application;

[0067] Figure 2 This is a structural schematic diagram of another angle of the high-water-content ABS powder extrusion dehydration equipment provided in an embodiment of the present application;

[0068] Figure 3 It is a schematic diagram of the overall structure of the extruder dehydrator barrel provided according to an embodiment of the present application;

[0069] Figure 4 It is a schematic diagram of the barrel structure of the extruder dehydration barrel provided in an embodiment of the present application;

[0070] Figure 5 yes Figure 1 AA section view;

[0071] Figure 6 It is a schematic diagram of the structure of a dewatering screen of an extruder dewatering barrel provided in an embodiment of the present application;

[0072] Figure 7 yes Figure 4 BB cross-sectional view;

[0073] Figure 8 is a schematic structural diagram of a plate provided with a drainage channel according to an embodiment of the present application;

[0074] Fig. 9 yes Figure 4 CC section view;

[0075] Fig.10 yes Figure 7 Enlarged view of the middle Z;

[0076] Fig.11 is a cross-sectional view of a dehydrator barrel of an extruder provided according to another embodiment of the present application;

[0077] Fig.12 It is an exploded view of the extruder dehydrator barrel structure provided according to another embodiment of the present application.

[0078] Reference numerals:

[0079] 1. ABS powder in the first state; 2. ABS powder in the final state; 10. Water;

[0080] 100, extrusion mechanism; 110, conveying section; 111, feeding port; 112, first conveying element; 120, first extrusion section; 121, first extrusion front section; 121-1, first extrusion element; 122, first extrusion rear section; 122-1, second extrusion element; 130, second extrusion section; 131, second extrusion front section; 131-1, third extrusion element; 132, second extrusion rear section; 132-1, fourth extrusion element; 140, crushing section; 141, crushing element; 150, dispersion section; 151, dispersion element; 152, second conveying element; 153, discharge port; 160, motor; 170, coupling; 180, reduction box;

[0081] 101, barrel; 102, barrel wall; 103, extrusion chamber; 104, dehydration port;

[0082] 200, dewatering mechanism; 210, dewatering screen; 211, plate; 212, drainage channel; 212-1, first drainage gap; 212-2, second drainage gap; 212-3, third drainage gap; 212', drainage groove; 212-1', first drainage groove; 212-2', second drainage groove; 212-3, third drainage groove; 213, plate fixing member; 213-1, clamping bolt; 213-2, positioning pin; 214, positioning hole; 220, fixing device; 221, convex pressure plate; 222, boss; 223, drainage outlet; 224, pressure plate locking bolt;

[0083] 300, cooling water channel; 310, cooling water inlet and outlet;

[0084] 400. Drainage mechanism;

[0085] 500. Feeding mechanism. DETAILED DESCRIPTION

[0086] Embodiments of the present application will be described in detail below, examples of which are shown in the accompanying drawings, and the components of the embodiments of the present application generally described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the application claimed for protection, but merely represents selected embodiments of the present application.

[0087] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0088] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0089] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0090] The following will be combined Figure 1 to Figure 12 The technical solution of the present application is described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments, and the pressures involved in the present application are all gauge pressures.

[0091] See also Figure 1 The first aspect of the present application provides a method for extrusion dehydration of high-water-content ABS powder, comprising the following steps:

[0092] Step S300, feeding the first-state ABS powder 1 into the first extrusion section 120 of the extrusion mechanism 100 for extrusion, applying an extrusion force of 1-10 MPa, and obtaining the third-state ABS powder;

[0093] The ABS powder with high water content, i.e., the first-state ABS powder 1, has a water content of no more than 50 wt%. Preferably, the water content of the first-state ABS powder 1 is 30-40 wt%. In some specific examples of the present application, the water content of the first-state ABS powder 1 can be 50 wt%, 45 wt%, 40 wt%, 35 wt%, 30 wt%, etc.

[0094] In some embodiments of the present application, in order to enhance the extrusion dehydration effect, the extrusion mechanism 100 may adopt a screw extruder, preferably a co-rotating twin-screw extruder.

[0095] In a specific example of the present application, the extrusion mechanism 100 adopts a KraussMaffei co-rotating twin-screw extruder ZE52GP, with a screw diameter of 52 cm, a motor power of 195 kW, and a maximum screw speed of 900 rpm.

[0096] Preferably, the speed of the KraussMaffei co-rotating twin-screw extruder ZE52GP during the extrusion dehydration process does not exceed 400 rpm; during the operation of the twin-screw extrusion dehydrator, the higher the screw speed, the more intense the friction heat generated, so the screw speed is controlled not to exceed 300 rpm, especially not to exceed 400 rpm, otherwise the material will be plasticized and agglomerated due to overheating, and the invention purpose of the present application cannot be achieved.

[0097] In some embodiments of the present application, in order to further enhance the heat dissipation and dehydration effects during extrusion, the extrusion mechanism 100 includes a first extrusion section 120, a second extrusion section 130, a crushing section 140 and a dispersion section 150, and each section is combined and spliced ​​into the extrusion mechanism 100. Among them, the lengths of the first extrusion section 120, the second extrusion section 130, the crushing section 140 and the dispersion section 150 are not limited by this embodiment, and those skilled in the art can adjust the lengths according to the process objectives of each stage. The first extrusion section and the second extrusion section are the key to the present invention. The two extrusion sections respectively implement two different processing processes. The lengths of the two sections can be adjusted by those skilled in the art according to the actual screw speed in combination with the process conditions and the need to extrude moisture.

[0098] In a specific example of the present application, the first extrusion section 120 is mainly composed of two sections of extrusion barrels 101, namely the first extrusion front section 121 and the first extrusion rear section 122. The barrel 101 of the first extrusion rear section 122 can be a dehydrating barrel. The first extrusion front section 121 includes a first extrusion element 121-1, and the first extrusion rear section 122 includes a second extrusion element 122-1 to extrude the first state ABS powder. The length of the first extrusion front section 121 and the first extrusion rear section 122 is unlimited, and the front and rear ratio is adjusted for the purpose of completing the processing process. Its main purpose is to achieve the third state of the powder (the water content of the ABS powder is 20~25wt%) through the technical solution of low temperature and low pressure and then relatively increasing the temperature and pressure in different stages. In some embodiments of the present application, the length ratio of the first extrusion front section 121 and the first extrusion rear section 122 is 1:1~1:2.

[0099] The pressure applied by the first extrusion section 120 in cooperation with the first extrusion element 122-1 and the second extrusion element 122-1 to the ABS powder is 1-10 MPa, preferably 4-6 MPa. In some specific examples of the present application, the pressure may be 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, etc.

[0100] In some embodiments of the present application, the temperature can be controlled by various means such as controlling the screw speed of the screw extruder, the extrusion pressure, and cooling by cooling water. Those skilled in the art can choose which means to control the temperature according to actual production.

[0101] In some embodiments of the present application, a cooling water channel 300 is arranged inside the dehydration barrel 101 to achieve a temperature control effect.

[0102] In some embodiments of the present application, in order to achieve a better squeezing and dehydration effect, the step S300 includes:

[0103] S301, feeding the first-state ABS powder into the first extrusion front section 121 of the extrusion mechanism 100 for extrusion, and then obtaining the second-state ABS powder;

[0104] S302, feeding the ABS powder in the second state into the first extrusion rear section 122 of the extrusion mechanism 100 for extrusion, and at the same time, draining the extruded water 10 through the dehydration mechanism 200 and the drainage mechanism 400 of the dehydration barrel 101, and then obtaining the ABS powder in the third state;

[0105] Among them, during the extrusion process of the first extrusion front section 121, the pressure range is 1~4MPa, and the temperature is 25~35℃; during the extrusion process of the first extrusion rear section 122, the pressure range is 4~6MPa, and the temperature is 35~45℃. The first state to the third state is a process of more dehydration. The first state ABS powder 1 is slowly heated and pressurized in the first extrusion front section 121, so that it is gradually increased from a low pressure of 1MPa and a low temperature of 25℃ to 4MPa, 35℃, avoiding directly entering the temperature (minimum 35℃) and pressure (minimum 4MPa) of the first extrusion rear section 122, which causes the ABS powder to produce adverse phenomena such as agglomeration and plasticization due to the sudden change of temperature and pressure. The second state ABS powder is further heated and pressurized in the first extrusion rear section 122. Generally speaking, in the twin-screw extrusion dehydration process, the treatment process is best when the length of the first extrusion front section 121 and the first extrusion rear section 122 is controlled at 1:2, and the obtained third state ABS powder is less likely to be plasticized when entering the second extrusion section 130 for deep dehydration.

[0106] In some specific examples, the pressure in the first extrusion section 120 of the extrusion mechanism 100 gradually increases, causing the temperature to gradually increase. The present application does not limit the pressure increase rate or the temperature increase rate, and those skilled in the art can adjust it as needed.

[0107] The present application extrudes the material by dividing the first extrusion section 120 into two sections, so that the pressure and temperature during the extrusion process can be more finely controlled, thereby improving the dehydration efficiency and preventing the ABS powder from being plasticized.

[0108] Step S400, feeding the ABS powder in the third state into the second extrusion section 130 of the extrusion mechanism 100 for extrusion, applying an extrusion force of 6-15 MPa, and obtaining the ABS powder in the fifth state;

[0109] Among them, after being extruded by the first extrusion section 120, the water content of the third-state ABS powder obtained is 20~25wt%. In some specific examples of the present application, the water content of the third-state ABS powder can be 20 wt%, 21 wt%, 22 wt%, 23wt%, 24 wt%, 25 wt%, etc.

[0110] The maximum temperature of the ABS powder in the second extrusion section needs to be controlled at the critical point of the plasticizing temperature, that is, below 90°C, otherwise the wet ABS powder will begin to plasticize.

[0111] In some embodiments of the present application, the second extrusion section 130 is mainly composed of two sections of extrusion barrels 101, namely, the second extrusion front section 131 and the second extrusion rear section 132. The barrel 101 of the second extrusion rear section 132 can be a dehydrating barrel. The second extrusion front section 131 includes a third extrusion element 131-1, and the second extrusion rear section 132 includes a fourth extrusion element 132-1 to extrude the second state ABS powder. The length of the second extrusion front section 131 and the second extrusion rear section 132 is also not limited, and can be adaptively adjusted according to the needs of completing the processing process. The purpose is mainly to further increase the temperature and pressure in stages on the basis of the temperature and pressure of the first extrusion section to further process the third state ABS powder into the fifth state ABS powder (water content of 12~18wt%). In some embodiments of the present application, the length ratio of the second extrusion front section 131 and the second extrusion rear section 132 is 1:1~1:2.

[0112] The second extrusion section 130 cooperates with the third extrusion element 131-1 and the fourth extrusion element 132-1 to apply a pressure of 6 to 15 MPa, preferably 8 to 12 MPa to the ABS powder. In some specific examples of the present application, the pressure can be 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, 11 MPa, 12 MPa, 13 MPa, 14 MPa, 15 MPa, etc. Increasing the extrusion force helps to reduce the moisture content in the ABS powder, but if the extrusion force is too large, it may hinder the flow of the material, thereby affecting production efficiency. In order to avoid a significant reduction in output, the extrusion force should be designed reasonably, and it is generally recommended not to exceed 15 MPa, so that the output can be kept at an acceptable level while effectively removing moisture.

[0113] In some embodiments of the present application, in order to enhance the drainage effect, the process of obtaining the fifth-state ABS powder from the first-state ABS powder 1 includes:

[0114] Drainage is performed by at least one side drainage mechanism 400 connected laterally to the first extrusion section 120 of the extrusion mechanism 100 or the second extrusion section 130 of the extrusion mechanism 100 .

[0115] The side drainage mechanism 400 may be a side drainage machine or other equipment for drainage.

[0116] In some embodiments of the present application, both sides of the first extrusion rear section 122 and both sides of the second extrusion rear section 132 are correspondingly connected with side drainage machines 200 to discharge the extrusion water 10 in time during the ABS powder extrusion process.

[0117] In some embodiments of the present application, in order to further enhance the extrusion dehydration effect and prevent the ABS powder from plasticizing, the step S400 includes:

[0118] S401, feeding the ABS powder in the third state into the second extrusion front section 131 of the extrusion mechanism for extrusion, and then obtaining the ABS powder in the fourth state;

[0119] S402, feeding the ABS powder in the fourth state into the second extrusion rear section 132 of the extrusion mechanism for extrusion, and at the same time, draining the extruded water 10 through the dehydration mechanism 200 and the drainage mechanism 400 of the dehydration barrel 101, and then obtaining the ABS powder in the fifth state;

[0120] Among them, the pressure range during the extrusion process of the second extrusion front section 131 is 6~8MPa, and the temperature range is 45~60℃; the pressure range during the extrusion process of the second extrusion rear section 132 is 8~12MPa, and the temperature range is 60~85℃. The process from the third state ABS powder to the fifth state ABS powder is a process of further dehydration until the desired ABS powder water content is reached; the process from the third state ABS powder to the fourth state ABS powder is to further increase the temperature in the range of 45~60℃ and gradually increase the pressure in the range of 6~8MPa relative to the previous process, and the pressure changes in the range of 6~8MPa with a small change range. The process from the fourth state ABS powder to the fifth state ABS powder is based on the temperature of the previous process, further increasing in the range of 60~85℃, and increasing in the range of 8~12MPa. The temperature of the second extrusion rear section 132 is controlled at a higher temperature and below the critical temperature of plasticization to dehydrate as much as possible and ensure that ABS avoids plasticization. Through segmented control, the temperature and pressure of each extrusion section can be maintained within the optimal processing range of the material, which can more effectively remove moisture and avoid premature plasticization of the material.

[0121] In some specific examples, the pressure in the second extrusion section 130 of the extrusion mechanism 100 gradually increases, causing the temperature to gradually increase. The present application does not limit the pressure increase rate or the temperature increase rate, and those skilled in the art can adjust it as needed.

[0122] By performing segmented extrusion in the second extrusion process, each stage can be maintained within the optimal temperature and pressure range of the material. By gradually increasing the temperature and pressure, the ABS powder can be prevented from being plasticized prematurely due to excessive temperature, while allowing extrusion to release more water.

[0123] Step S500, the fifth state ABS powder is crushed and dispersed by the crushing section 140 and the dispersing section 150 of the extrusion mechanism 100 to obtain the final state ABS powder 2;

[0124] Among them, after extrusion by the second extrusion section 130, the water content of the fifth state ABS powder obtained is 12~18wt%. In some specific examples of the present application, the water content of the fifth state ABS powder can be 12 wt%, 13 wt%, 14 wt%, 15wt%, 16 wt%, 17 wt%, 18wt%, etc.

[0125] In some embodiments of the present application, in order to crush and disperse the agglomerated ABS powder after extrusion and dehydration, the step S500 includes:

[0126] Step S501: The crushing element 141 in the crushing section 140 of the extrusion mechanism 100 crushes the ABS powder in the fifth state to obtain ABS powder in the sixth state. The size of the ABS powder in the sixth state does not exceed 5 mm, and the water content is 12-18 wt %.

[0127] Step S502: The second dispersing element 151 in the dispersing section 150 of the extrusion mechanism 100 further crushes and disperses the ABS powder in the sixth state, so that the ABS powder is crushed and dispersed into particles with a size not exceeding 3 mm, thereby obtaining the final state ABS powder 2;

[0128] Step S503 : the second conveying element 152 in the dispersing section 150 of the extrusion mechanism 100 discharges the ABS powder 2 in the final state from the discharge port 153 of the dispersing section 150 .

[0129] Among them, the water content of the ABS powder 2 in the final state is 12~18wt%. In some specific examples of the present application, the water content of the ABS powder 2 in the final state can be 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18wt%, etc.

[0130] By first crushing and then dispersing the ABS powder, it can be thoroughly dispersed into particles not exceeding 3 mm, which is helpful for subsequent production and use. At the same time, it is directly discharged through the dispersion section 150 to avoid material accumulation in the equipment.

[0131] In some embodiments of the present application, in order to feed the first-state ABS powder 1 into the extrusion mechanism 100, the step before step S300 includes:

[0132] The first state ABS powder 1 is fed into the conveying section 110 of the extrusion mechanism 100 through the feeding port 111 opened on the conveying section 110 by the feeding mechanism 500;

[0133] The first conveying element 112 in the conveying section 110 of the extrusion mechanism 100 conveys the ABS powder material 1 in the first state with a relatively low bulk density into the first extrusion section 120 of the extrusion mechanism 100 .

[0134] In some embodiments of the present application, the feeding mechanism 500 may be a screw feeder to enhance feeding stability. The first state ABS powder 1 is fed into the first extrusion section 120 through the conveying section 110 to avoid affecting the pressure in the first extrusion section 120 .

[0135] In some embodiments of the present application, the extrusion mechanism 100 specifically uses a twin-screw extruder, including a screw mandrel and a screw element sleeved on the screw mandrel. In actual production, the structure of the screw element and the combination of different screw elements can be adjusted to achieve the desired function. In a specific example of the present application, the first conveying element 112, the first extruding element 121-1, the second extruding element 122-1, the third extruding element 131-1, the fourth extruding element 132-1, and the second conveying element 152 are specifically screw elements of the spiral structure of the twin-screw extruder, and the spiral shape can be adjusted and set according to the functional needs of the twin-screw extruder. The crushing element 141 and the dispersing element 151 are also screw elements. Those skilled in the art can adjust the structure according to the actual production needs. The main function is to break up and disperse large materials into small particles.

[0136] The number and arrangement of the extrusion sections in the extrusion mechanism 100 can be adjusted according to actual production conditions, different extrusion pressure areas can be set, and ABS powder with different moisture contents can be obtained. The present application can conveniently achieve the moisture content of the final product by adjusting the extrusion pressure of multiple extrusion sections according to the different moisture contents of the final product required.

[0137] ABS powders with different moisture contents can be produced by setting different extrusion pressure zones in the extrusion mechanism 100. The present application allows the pressure at each stage of the extrusion process to be adjusted according to the moisture content required by the final product, thereby achieving control of the humidity of the ABS powder in the final state.

[0138] The moisture content of the ABS powder treated by the dehydration method of the present application is below 18wt%, and the particle size is within 3mm, so that in the subsequent resin production process, ABS resin with less yellowing, better gloss and higher impact strength can be produced, significantly improving the quality of the final product.

[0139] See also Figures 1 to 12 In a second aspect, the present application provides an ABS powder extrusion and dehydration device with a high water content, which is used to complete the above method. The device includes: an extrusion mechanism 100, a drainage mechanism 400 and a feeding mechanism 500;

[0140] The extrusion mechanism 100 is mainly composed of a conveying section 110, a first extrusion section 120, a second extrusion section 130, a crushing section 140, and a dispersion section 150.

[0141] The feeding mechanism 500 is connected to the extrusion mechanism 100 through the feeding port 111 on the conveying section 110 to convey the ABS powder in the first state to the extrusion mechanism 100;

[0142] The conveying section 110 includes a first conveying element 112 to convey the ABS powder in the first state to the first extrusion section 120;

[0143] The first extrusion section 120 is mainly composed of a first extrusion front section 121 and a first extrusion rear section 122. The drainage mechanism 400 is connected to the extrusion mechanism 100 through the dehydration barrel 101 of the first extrusion rear section 122 to discharge the extruded water 10.

[0144] The first extrusion front section 121 includes a first extrusion element 121 - 1 , and the first extrusion rear section 122 includes a second extrusion element 122 - 1 ;

[0145] The second extrusion section 130 is mainly composed of a second extrusion front section 131 and a second extrusion rear section 132. The drainage mechanism 400 is connected to the extrusion mechanism 100 through the dehydration barrel 101 of the second extrusion rear section 132 to discharge the extruded water 10.

[0146] The second extrusion front section 131 includes a third extrusion element 131 - 1 , and the second extrusion rear section 132 includes a fourth extrusion element 132 - 1 ;

[0147] The crushing section 140 includes a crushing element 141 , and the dispersing section 150 includes a dispersing element 151 , a second conveying element 152 and a discharge port 153 .

[0148] The extrusion mechanism 100 further includes: a motor 160, a coupling 170, and a reduction box 180. The motor 160 is connected to the coupling 170, and the coupling 170 is connected to a power element of the pressure control mechanism 100, and provides power for the extrusion mechanism after speed control by the reduction box 180.

[0149] See also Figures 3 to 5 Some embodiments of the present application provide an extruder dehydration barrel, comprising: a barrel 101 and a dehydration mechanism 200,

[0150] The barrel 101 includes a barrel wall 102 and an extrusion cavity 103 formed by the barrel wall 102. At least one dehydration port 104 is opened on the barrel wall 102 on the outer side of the barrel 101.

[0151] The dewatering mechanism 200 includes a dewatering screen 210 and a fixing device 220, wherein:

[0152] The dewatering screen 210 is disposed in the dewatering port 104 and is matched with the cylinder wall 102 inside the dewatering port. The fixing device 220 is used to fix the dewatering screen 120 in the dewatering port 104;

[0153] The dewatering screen 210 includes at least two plates 211 , and at least one drainage channel 212 is formed between two adjacent plates 211 .

[0154] The barrel 101 is a dehydrating barrel commonly used in extruders in the art, such as a dehydrating barrel of a single-screw extruder or a twin-screw extruder. The barrel 101 extrude the plastic raw material powder through a middle extrusion cavity 103 to dehydrate it.

[0155] The dehydration port 104 is provided on the side of the barrel 101, and the depth of the dehydration port 104 is based on the connection to the extrusion chamber 103, so that the water squeezed out of the extrusion chamber 103 can be discharged through the drainage channel 212 in the dehydration port 104. The present application does not limit the shape of the dehydration port 104, as long as it can discharge the water in the extrusion chamber 103.

[0156] The side of the dewatering screen 210 facing the extrusion chamber 103 should fit the shape of the extrusion chamber 103 to prevent the dewatering screen 210 from occupying the extrusion space of the extrusion chamber 103 .

[0157] The dewatering screen 210 includes at least two stacked plates 211 . This design allows the filtering area to be increased or decreased by increasing or decreasing the number of plates 211 to meet the needs of opening dewatering ports 104 of different sizes, while also reducing the difficulty of processing the drainage channel 212 .

[0158] The dewatering screen 210 can match the shape of the inner cylinder wall 102 at the dewatering port 104 by adjusting the number and shape of the plates 211 to prevent the plastic raw material powder in the extrusion cavity 103 from leaking out and to drain water.

[0159] One or more drainage channels 212 are formed between adjacent plates 211, and the size of the drainage channels 212 can be set according to the dehydrated plastic raw material powder to meet different filtering requirements. By accurately controlling the gap and pore size between the sieve plates, the dewatering screen 211 can effectively separate and discharge the moisture in the plastic raw material powder, thereby optimizing the dehydration efficiency, reducing the clogging of the material and the wear of the sieve plate, and extending the service life of the equipment.

[0160] The fixing device 220 is fixed on the barrel wall 102 on the outer side of the barrel 101, providing pressure from the outside to the inside to fix the dewatering screen 210 in the dewatering port 104. At the same time, the height of the dewatering screen 210 is higher than the extrusion chamber 103, so that the inside of the dewatering screen 210 is supported by the bottom of the dewatering port 104 opened in the barrel 101, thereby fixing the dewatering screen 210 in the dewatering port 104 and preventing the dewatering screen 210 from occupying the extrusion space of the extrusion chamber 103.

[0161] In a specific example of this application, see Figures 3 to 5The barrel 101 is a twin-screw extruder dehydration barrel, and its extrusion chamber 103 is opened in an "8" shape. Two dehydration ports 104 are opened on the barrel wall 102 outside the barrel 101, and connect the extrusion chamber 103 with the external space. The side of the dehydration screen 210 facing the extrusion chamber 103 is set to be semicircular, so as to fit the shape of the extrusion chamber 103, and the opening height of the dehydration port 104 and the height of the dehydration screen 210 are both greater than the cavity height of the extrusion chamber 103, so that when the external fixing device 220 is pressed inward, the dehydration screen 210 can use the inner barrel wall 102 of the dehydration port 104 as a support point, so that the dehydration screen 210 can receive the extruded water while not occupying the extrusion space of the extrusion chamber 103, and will not interfere with the extrusion operation. The fixing device 220 is fixed to the barrel wall 102 of the barrel 101 by bolts, so that the dehydration screen 210 is fixed in the dehydration port 104.

[0162] In some embodiments of the present application, the dewatering screen 210 includes a plate fixing member 213 . Positioning holes 214 penetrating through the plurality of plates 211 are formed on the dewatering screen 210 . The plate fixing member 213 fixes the filter screen plate 211 through the positioning holes 214 .

[0163] Furthermore, the plate fixing member 213 includes a clamping bolt 213 - 1 and a positioning pin 213 - 2 . The positioning pin 213 - 2 is disposed in the positioning hole 214 . The clamping bolt 213 - 1 is inserted into the positioning hole 214 and cooperates with the positioning pin 213 - 2 to stack and fix multiple plates 213 into a dewatering screen 210 .

[0164] The present application does not impose any restrictions on the shape, number and depth of the positioning holes 214 , and the plurality of plates 211 can be fixed relatively immobile in cooperation with the clamping bolts 213 - 1 and the positioning pins 213 - 2 .

[0165] The positioning pin 213-2 is used in conjunction with the clamping bolt 213-1, and is inserted into the positioning hole 214 to stack and fix multiple plates 211 to form the structure of the dewatering screen 210. By providing the positioning pin 213-2, it is possible to ensure that each plate 211 is accurately positioned in the dewatering screen 210, thereby ensuring the efficiency and effect of the screening process. In addition, the positioning pin 213-2 cooperates with the clamping bolt 213-1 to provide a firm fixation for the plate 211 to prevent displacement or vibration during the dewatering process.

[0166] In a specific example of this application, see Figures 6 to 8 After multiple plates 211 are stacked, two penetrating positioning holes 214 are opened. In each positioning hole 214, two upper and lower screen plate clamping bolts 213-1 are relatively fixed in the positioning hole 214, and each screen plate clamping bolt 213-1 is equipped with a screen plate positioning pin 213-2 to stack and fix multiple filter screen plates 211 into a dewatering screen 210.

[0167] In some embodiments of the present application, the drainage channel 212 includes a first drainage gap 212-1, a second drainage gap 212-2, and a third drainage gap 212-3, and a drainage groove 212' is provided on the plate 211, and the drainage groove 212' and the bottom surface of another plate on the upper part of the plate 211 form the drainage channel 212. The drainage groove 212' includes a first drainage groove 212-1', a second drainage groove 212-2', and a third drainage groove 212-3, wherein the first drainage groove 212-1', the second drainage groove 212-2' cooperate with the bottom surface of the upper plate 211 to form the first drainage gap 212-1, the second drainage gap 212-2, and the third drainage gap 212-3, respectively. The first drainage groove 212-1' is located near the extrusion cavity 103, and its depth is less than that of the third drainage groove 212-3'. The bottom surface of the second drainage groove 212-2' is inclined to connect the first drainage groove 212-1' and the third drainage groove 212-3'.

[0168] The first drainage gap 212-1 is located on the side of the dewatering screen 210 close to the extrusion chamber 103, and the third drainage gap 212-3 is located on the side away from the extrusion chamber 103 and close to the external environment. The first drainage gap 212-1 gradually expands away from the extrusion chamber 103, passing through the second drainage gap 212-2 to the third drainage gap 212-3.

[0169] Furthermore, the dewatering screen 210 includes a plurality of first drainage gaps 212 - 1 , and the lengths of the plurality of first drainage gaps 212 - 1 along the drainage direction are kept consistent.

[0170] In some embodiments of the present application, the dewatering screen 210 includes at least two parallel drainage channels 212 .

[0171] The present application does not limit the number and size of the drainage channels 212, and is based on meeting actual dehydration needs. However, the channel widths of some drainage channels 212 are different, which can ensure that when different positions of the dehydration screen 210 are subjected to squeezing pressure, the drainage channels 212 are not compressed and blocked.

[0172] The present application does not impose any restriction on the density of the drainage channels 212 , that is, plates 211 of different thicknesses may be used to adjust the density of the drainage channels 212 .

[0173] The first drainage gap 212-1 expands outward to form a third drainage gap 212-3, where the outside is relative to the outside of the extrusion chamber 103, that is, from the inside to the outside of the barrel. The height of the first drainage gap 212-1 is less than the height of the third drainage gap 212-3, which can not only prevent the material in the extrusion chamber 103 from leaking out of the first drainage gap 212-1, but also increase the drainage channel area, which helps to improve the drainage efficiency, ensure that the water can be smoothly discharged from the dewatering screen 210, avoid the loss of materials, and also help reduce the blockage problem of the equipment, thereby improving the operating efficiency and stability of the entire system.

[0174] The first drainage gaps 212 - 1 of the plurality of drainage channels 212 included in the dewatering screen 210 of the present application have the same length, thereby reducing the accumulation of materials therein and avoiding blockage of the drainage channels 212 .

[0175] In a specific example of this application, see Figures 8 to 10 , Figure 8 The plate 211 constituting the dewatering screen 210 in one embodiment of the present application is shown. The plate 211 can form three drainage channels 212 with the bottom surface of another plate 211 above it, and each drainage channel 212 includes a first drainage groove 212-1', a second drainage groove 212-2' and a third drainage groove 212-3. Fig. 9 The figure shows a drainage channel 212 formed by stacking a plurality of plates 211. Fig.10 yes Fig. 9 The enlarged part at Z in the middle, combined with Figures 8 to 10 It can be seen that three drainage channels 212 can be formed between two adjacent plates 211. Each drainage channel 212 has a first drainage gap 212-1 on one side close to the extrusion cavity 103, and then expands outward to expand to a third drainage gap 212-3 through a gradually expanding second drainage gap 212-2.

[0176] In some embodiments of the present application, the fixing device 220 includes a convex pressure plate 221 , a boss 222 is formed in the middle of the convex pressure plate 221 and can be inserted into the dehydration port 104 , a drainage port 223 is opened in the middle of the boss 222 , and the drainage channel 212 is connected to the external space through the drainage port 223 .

[0177] Furthermore, the fixing device 220 also includes a pressure plate locking bolt 224 , and the convex pressure plate 221 is fixed to the barrel 101 via the pressure plate locking bolt 224 .

[0178] The size of the convex pressing plate 221 should be based on the ability to fix the dewatering screen 210, and this application does not impose any limitation on this.

[0179] The drainage openings 223 formed on the convex pressure plate 221 should enable all drainage channels 212 to communicate with the outside without causing any obstruction.

[0180] The boss 222 can be inserted into the dewatering port 104 to directly contact the dewatering screen 210 therein, so as to more firmly fix the dewatering screen 210 .

[0181] The number of the pressure plate locking bolts 224 is based on the ability to firmly fix the convex pressure plate 221, and this application does not impose any limitation on this.

[0182] In a specific example of this application, see Figure 4 and Figure 5 There is a dehydration mechanism 200 on each side of the barrel, and each convex pressure plate 221 is fixed to the barrel 101 by two pressure plate locking bolts 224 on the upper and lower sides, and one pressure plate locking bolt 224 on the left and right sides. The shape and size of the boss 222 just match the size of the dehydration port 104, so that it can be inserted into the dehydration port 104 and contact with the dehydration screen 210, so that pressure can be applied to the dehydration screen 210 to fix it in the dehydration port 104.

[0183] In some embodiments of the present application, the opening direction of the dehydration port 104 is 0° to 90° with respect to the horizontal radial direction of the extrusion cavity 103 .

[0184] Preferably, the opening direction of the dehydration port 104 is 0° or 90° to the horizontal radial direction of the extrusion chamber 103 .

[0185] By adjusting the opening angle of the dewatering port 104 , the water released from the extrusion cavity 103 can be discharged more easily.

[0186] In a specific example of this application, see Fig.11 The opening directions of the two opposite dewatering ports 104 on the barrel 101 are at an acute angle to the horizontal radial direction of the extrusion chamber 103, that is, the dewatering ports 104 are opened obliquely downward, so that the dewatering screen 210 and the drainage channel 212 are both obliquely downward, which can make the water released from the extrusion chamber 103 more easily discharged under the action of its own gravity, thereby enhancing the drainage effect.

[0187] In a specific example of this application, see Fig.12 Two opposite dehydration ports 104 on the barrel 101 are opened obliquely downward, and a third dehydration port 104 perpendicular to the horizontal radial direction of the extrusion chamber 103 is opened on the barrel 101 at the bottom of the extrusion chamber 103, and the above-mentioned dehydration mechanism 200 is also arranged therein, which further enhances the drainage effect.

[0188] According to one aspect of the present application, a cooling water channel 300 is provided in the barrel 101 , and the cooling water channel 300 is arranged close to the extrusion chamber 103 .

[0189] In a specific example of this application, see Figure 3-Figure 5The cooling water channel 300 is arranged at the upper and lower parts of the extrusion chamber 103 inside the dehydration barrel 101, and is not in direct contact with the extrusion chamber 103, but is arranged close to the inner wall of the extrusion chamber 103, so as to ensure that the extrusion heat in the barrel 101 is taken away by the cooling water in time and the material temperature is maintained stable. The surface of the barrel 101 is provided with a cooling water inlet and outlet 310 to realize the flow of cooling water and enhance the heat dissipation effect of the equipment.

[0190] See also Figure 1-Figure 12 , the following is a specific embodiment of the present application:

[0191] Example 1

[0192] The first state ABS powder 1 with a water content of 40 wt% is fed into the conveying section 110 of the KraussMaffei co-rotating twin-screw extruder ZE52GP through the feeding port 111 by the screw feeder 300;

[0193] The conveying section 110 conveys the first-state ABS powder to the first extrusion front section 121 through the first conveying element 112. At this time, the output of the conveying section 110 is 300 kg / h, the rotation speed is 160 rpm, the pressure is 0 MPa, the temperature is 25°C, and the real-time water content of the first-state ABS powder delivered by the conveying section 110 is 40wt%;

[0194] The first extrusion front section 121 extrude and transmit the first-state ABS powder through the first extrusion element 121-1 inside it to obtain the second-state ABS powder. At this time, the pressure of the first extrusion front section 121 becomes 1-4MPa increasing, and the temperature becomes 30°C. The real-time water content of the second-state ABS powder is 40wt%. Part of the water in the extruded ABS powder is analyzed out of the powder surface and continues to move forward with the ABS powder.

[0195] The first extrusion rear section 122 receives the powder transmitted by the front section, and extrudes and transmits it through the second extrusion element 122-1 inside it under the temperature control of the cooling water channel 300 to obtain the third state ABS powder. At the same time, the extruded water 10 is discharged by using two side drainers 200 connected to the dehydrating barrel 101;

[0196] At this time, the pressure of the first extrusion rear section 122 increases gradually from 4 to 6 MPa, and the temperature becomes 40° C. The real-time moisture content of the third-state ABS powder delivered by the first extrusion rear section 122 is 22wt%;

[0197] The second extrusion front section 131 receives the third state ABS powder, and extrude and transmit it through the third extrusion element 131-1 inside to obtain the fourth state ABS powder. At this time, the internal pressure of the second extrusion front section 131 increases by 6-8 MPa, and the temperature becomes 50°C. The real-time water content of the fourth state ABS powder delivered by the second extrusion front section 131 is 22wt%;

[0198] The second extrusion rear section 132 receives the fourth state ABS powder, and extrudes and transmits it through the third extrusion element 131-1 inside it under the temperature control of the cooling water channel 300 to obtain the fifth state ABS powder. At the same time, the extruded water is discharged by two side drainers 200 connected to the dehydrating barrel 101;

[0199] At this time, the internal pressure of the second extrusion rear section 132 increases gradually from 8 to 12 MPa, and the temperature becomes 80° C. The real-time water content of the fifth-state ABS powder delivered by the second extrusion rear section 132 is 12wt%;

[0200] The crushing section 140 receives the fifth state ABS powder, and crushes the fifth state ABS powder into small lumps through the crushing element 141 inside it, so as to obtain the sixth state ABS powder. At this time, the internal pressure of the crushing section 140 becomes 1MPa, the temperature becomes 80°C, and the real-time water content of the sixth state ABS powder delivered by the crushing section 140 is 12wt%;

[0201] The dispersion section 150 receives the sixth state ABS powder, and further breaks up and disperses the small lumps of the sixth state ABS powder into fine powder through the dispersion element 151 inside it, to obtain the final state ABS powder, and then discharges it from the discharge port 153 through the second conveying element 152. At this time, the pressure of the dispersion section 150 is 0 MPa, and the temperature becomes 70° C. after cooling. The real-time water content of the final state ABS powder 2 delivered by the dispersion section 150 is 12wt%, and it still maintains a complete powder state.

[0202] It should be noted that the technical solutions in the various embodiments of the present application can be combined with each other, but the basis for the mutual combination is that it can be implemented by ordinary technicians in the field; when the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist, that is, it does not belong to the scope of protection of this application.

[0203] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for extruding and dehydrating ABS powder with high water content, characterized in that: The following steps are involved: The ABS powder in the first state is fed into the first extrusion section of the extrusion mechanism for extrusion, and an extrusion pressure of 1 to 6 MPa is applied to obtain the ABS powder in the third state; The ABS powder in the third state is fed into the second extrusion section of the extrusion mechanism for extrusion, and an extrusion pressure of 6 to 12 MPa is applied to obtain the ABS powder in the fifth state; The fifth state ABS powder is crushed and dispersed in the crushing section and dispersion section of the extrusion mechanism to obtain the final state ABS powder; The maximum temperature of the ABS powder during the extrusion dehydration process does not exceed 90°C, the moisture content of the ABS powder in the first state does not exceed 50wt%, the moisture content of the ABS powder in the third state is 20-25wt%, the moisture content of the ABS powder in the fifth state is 12-18wt%, and the moisture content of the ABS powder in the final state is 12-18wt%; The step of feeding the first state ABS powder into the first extrusion section of the extrusion mechanism for extrusion includes a first extrusion front section processing process and a first extrusion back section processing process, and the specific execution method is as follows: The first extrusion front section treatment process is: sending the first state ABS powder into the first extrusion front section of the extrusion mechanism with a pressure range of 1-4MPa and a temperature range of 25-35°C for extrusion to obtain the second state ABS powder; The first extrusion post-stage processing process is: the second state ABS powder is sent to the first extrusion post-stage of the extrusion mechanism with a pressure range of 4-6MPa and a temperature range of 35-45°C for extrusion to obtain the third state ABS powder; The first-state ABS powder is slowly heated and pressurized in the first extrusion front section, so that it gradually rises from a low pressure of 1MPa and a low temperature of 25°C to 4MPa and 35°C; the second-state ABS powder is further heated and pressurized in the first extrusion back section; The step of feeding the third state ABS powder into the second extrusion section of the extrusion mechanism for extrusion includes a second extrusion front section processing process and a second extrusion back section processing process, and the specific execution method is as follows: The second extrusion front-end processing process is: the third state ABS powder is sent to the second extrusion front-end of the extrusion mechanism with a pressure range of 6-8MPa and a temperature range of 45-60°C for extrusion to obtain the fourth state ABS powder; The second extrusion post-stage processing process is: sending the fourth state ABS powder into the second extrusion post-stage of the extrusion mechanism with a pressure range of 8-12MPa and a temperature range of 60-85°C for extrusion to obtain the fifth state ABS powder; Among them, the process from the third state ABS powder to the fourth state ABS powder is to gradually increase the temperature within the range of 45~60℃, and gradually increase the pressure within the range of 6~8MPa; the process from the fourth state ABS powder to the fifth state ABS powder is to further increase the temperature within the range of 60~85℃ and the pressure within the range of 8~12MPa on the basis of the previous process.

2. The method according to claim 1, characterized in that The process of obtaining the fifth-state ABS powder from the first-state ABS powder includes: Drainage is performed by at least one drainage mechanism connected laterally to the first pressing section of the pressing mechanism or to the second pressing section of the pressing mechanism.

3. The method according to claim 1, characterized in that The step of feeding the first-state ABS powder into the first extrusion section of the extrusion mechanism for extrusion comprises: The ABS powder in the first state is conveyed to the first extrusion section through the conveying section of the extrusion mechanism.

4. The method according to claim 1, characterized in that: The first-state ABS powder is an ABS powder with a high water content, and the water content thereof is 30-40wt%.

5. The method according to claim 1, characterized in that: The fifth state of the ABS powder in the step is crushed and dispersed by the extrusion mechanism to obtain the final state of the ABS powder, which includes: The crushing element in the crushing section of the extrusion mechanism crushes the fifth state ABS powder to obtain the sixth state ABS powder; The dispersing element in the dispersing section of the extrusion mechanism further crushes and disperses the ABS powder in the sixth state to obtain ABS powder in the final state; The second conveying element in the dispersing section of the extrusion mechanism discharges the ABS powder in the final state.

6. The method according to claim 5, characterized in that The particle size of the sixth-state ABS powder does not exceed 5 mm, and the water content is 12-18 wt%.

7. The method according to claim 1, characterized in that The particle size of the ABS powder in the final state does not exceed 3 mm.

8. The method according to claim 1, characterized in that The extrusion mechanism is a twin-screw extruder, and the speed of the twin-screw extruder during the extrusion dehydration process does not exceed 400 rpm.

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