Equipment and method for producing ABS (Acrylonitrile Butadiene Styrene) resin

Abstract

The invention relates to the technical field of ABS (Acrylonitrile Butadiene Styrene) resin material production, and provides ABS resin production equipment and a method. The ABS resin production equipment comprises a double-screw extruder and at least one side exhaust screw machine; a core shaft and a screw rod which is mounted on the core shaft and consists of building block type thread elements are arranged in the double-screw extruder, and the double-screw extruder comprises at least one exhaust section; at least one exhaust section is connected with a side exhaust screw machine, a screw is arranged in the side exhaust screw machine, and the side exhaust screw machine is connected with an external air extractor; and a screw in the side exhaust screw machine rotates towards one side of the double-screw extruder and is used for applying pressure towards one side of the double-screw extruder to materials. The side exhaust screw machine is directly connected with the double-screw extruder, so that moisture which is heated and gasified into steam in material production can be directly discharged, and meanwhile, materials are not discharged, so that the shutdown caused by material blockage is effectively prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of ABS resin production, and in particular to an ABS resin production device and method. Background Art

[0002] ABS plastic is a ternary copolymer of acrylonitrile (A), butadiene (B) and styrene (S). Its molecular formula can be written as (C8H8·C4H6·C3H3N)x. The relative contents of the three monomers can be changed arbitrarily to make various resins.

[0003] There is an existing preparation method of a small amount of melt SAN. The method mainly involves first sending the melt SAN to the front end of the twin-screw extruder inlet through a melt pump, and then feeding the ABS rubber powder particles used for blending and toughening through the side through a side screw machine for blending and blending. In this method, because the melt enters the twin-screw extruder first, the ABS rubber powder containing a certain amount of water will encounter the high-temperature melt SAN already in the extruder, and the water contained in the ABS rubber powder will quickly and continuously vaporize to produce a large amount of water vapor. According to production verification, the water vapor will hold up the side screw machine and flow back along the gap of the side screw machine, seriously affecting the feeding stability, often blocking the machine and stopping the machine, causing great trouble to production, and easily reducing the output of the product and failing to achieve the required production quality. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the present invention provides an apparatus and method for producing ABS resin, wherein a side exhaust screw machine is installed on a twin-screw extruder, which can exhaust steam in time, prevent material blocking and shutdown, and increase product production.

[0005] An apparatus for producing ABS resin according to an embodiment of the present invention includes: a twin-screw extruder and at least one side exhaust screw extruder;

[0006] The twin-screw extruder is provided with a screw composed of a mandrel and a modular screw element mounted on the mandrel, and the twin-screw extruder includes at least one exhaust section;

[0007] The at least one exhaust section is respectively connected to a side exhaust screw machine, and a screw is arranged inside the side exhaust screw machine;

[0008] The screw in the side exhaust screw machine rotates toward one side of the twin-screw extruder to apply pressure to the material toward one side of the twin-screw extruder.

[0009] According to the equipment for producing ABS resin in the embodiment of the present invention, the exhaust section is correspondingly provided with an exhaust port, and the side exhaust screw machine is connected with the twin-screw extruder through the exhaust port.

[0010] According to the equipment for producing ABS resin in the embodiment of the present invention, the twin-screw extruder further comprises: a feeding and conveying zone, a plasticizing and mixing zone, and a pressure building section;

[0011] The feeding and conveying zone, the plasticizing and mixing zone, the at least one exhaust section and the pressure building section are connected in sequence.

[0012] According to the equipment for producing ABS resin of the embodiment of the present invention, the feeding and conveying area is composed of a first cylinder, a second cylinder and a third cylinder connected in sequence;

[0013] The first cylinder is provided with a first feeding port, and the first feeding port is used to feed ABS rubber powder and other materials to be processed;

[0014] The third cylinder is provided with a second feeding port, and the second feeding port is used for feeding the melt SAN.

[0015] According to the equipment for producing ABS resin in the embodiment of the present invention, the length of the second barrel is: L1=(2-8)×D, wherein D is the diameter of the screw element of the twin-screw extruder.

[0016] According to the apparatus for producing ABS resin in the embodiment of the present invention, the lead of the thread of the corresponding mandrel in the second barrel gradually decreases, and the ratio of the maximum lead divided by the minimum lead, that is, the compression ratio, is not less than 1.5.

[0017] According to the equipment for producing ABS resin in the embodiment of the present invention, the plasticizing and mixing zone is composed of a plurality of cylinders connected in sequence.

[0018] According to the equipment for producing ABS resin according to the embodiment of the present invention, the exhaust section is composed of a front section and a rear section connected in sequence;

[0019] The front section is provided with an injection port, and the injection port can be used to add devolatilization-aiding materials;

[0020] The exhaust port is opened on the rear section.

[0021] According to the equipment for producing ABS resin in an embodiment of the present invention, the devolatilization material includes but is not limited to devolatilization water, the injection amount of the devolatilization water is 0.4wt% to 0.6wt% of the ABS resin output and the water temperature does not exceed 60°C.

[0022] According to the equipment for producing ABS resin in the embodiment of the present invention, the length of the exhaust section is: L=(4-10)×D, wherein D is the diameter of the screw element of the twin-screw extruder.

[0023] According to the equipment for producing ABS resin in the embodiment of the present invention, the length of the pressure building section is: L5=(4-10)×D, wherein D is the diameter of the screw element of the twin-screw extruder.

[0024] According to the apparatus for producing ABS resin according to an embodiment of the present invention, the threaded element includes a conveying thread and a shearing thread;

[0025] The conveying screw thread is arranged in the feeding and conveying area, the rear section of the exhaust section and the pressure building section;

[0026] The shearing threads are arranged in the plasticizing and mixing zone and the front section of the exhaust section, and the shearing threads are used for shearing and mixing materials.

[0027] According to the equipment for producing ABS resin in the embodiment of the present invention, the materials include but are not limited to ABS rubber powder, melt SAN, production aids, recycled ABS particles or recycled SAN.

[0028] According to the equipment for producing ABS resin in the embodiment of the present invention, the water content of the ABS rubber powder particles does not exceed 20wt%.

[0029] According to the equipment for producing ABS resin in the embodiment of the present invention, the amount of recycled ABS particles and recycled SAN does not exceed 20%.

[0030] A method for producing ABS resin according to an embodiment of the present invention, based on any one of the equipment for producing ABS resin, comprises:

[0031] S1: adding ABS rubber powder with a water content of no more than 20wt% and other materials to be processed into a twin-screw extruder, and then advancing the powder forward for at least a first distance and mixing the powder with the melt SAN added into the screw extruder to obtain a first mixed material;

[0032] wherein the pushing process causes the materials to be mixed and compacted; the first distance L2 = (4-10) × D, wherein D is the diameter of the screw element of the twin-screw extruder;

[0033] S2: The first mixed material is heated and degassed to obtain ABS resin.

[0034] According to the method for producing ABS resin in an embodiment of the present invention, the method for preparing the first mixed material, the step S1 comprises:

[0035] S11: feeding ABS rubber powder with a water content not exceeding 20wt% and other materials to be processed into the first cylinder of the feeding and conveying area through the first feeding port;

[0036] S12: transporting ABS rubber powder with a water content of no more than 20wt% and other materials to be processed through the second cylinder to the third cylinder;

[0037] S13: The molten SAN is fed into the third cylinder through the second feeding port, and is transported to the plasticizing and kneading zone together with the ABS rubber powder and other materials to be processed, and is uniformly kneaded by shearing to obtain a first mixed material.

[0038] According to the method for producing ABS resin according to an embodiment of the present invention, the step S2 further includes:

[0039] The first mixed material is connected to a vacuum system in the exhaust section, and the moisture in the first mixed material is evaporated by external heating and shear heat generation, and the steam is discharged through the side exhaust screw machine to obtain ABS resin. At the same time, the screw of the side exhaust screw machine returns the first mixed material taken out of the steam to the exhaust section.

[0040] According to the method for producing ABS resin according to an embodiment of the present invention, the pressure of the vacuum system is 0 kPaA-100 kPaA.

[0041] According to the method for producing ABS resin in an embodiment of the present invention, the devolatilization material includes but is not limited to devolatilization water, the injection amount of the devolatilization water is 0.4wt% to 0.6wt% of the ABS resin output and the water temperature does not exceed 60°C.

[0042] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0043] One embodiment of the present invention provides an apparatus and method for producing ABS resin, including a twin-screw extruder and at least one side exhaust screw machine; the twin-screw extruder is provided with a core shaft and a screw composed of a building block-type threaded element installed on the core shaft, and the twin-screw extruder includes at least one exhaust section; the at least one exhaust section is respectively connected to a side exhaust screw machine, the side exhaust screw machine is provided with a screw, and the side exhaust screw machine is connected to an external exhaust device, which is used to discharge the moisture of the processed material in the twin-screw extruder through the exhaust section and the side exhaust screw machine; the screw in the side exhaust screw machine rotates toward one side of the twin-screw extruder, which is used to apply pressure to the material on one side of the twin-screw extruder. By directly connecting the side exhaust screw machine to the twin-screw extruder, the moisture in the material that is heated and vaporized into steam can be directly discharged while the material is not discharged, effectively preventing material blockage and shutdown;

[0044] Another embodiment of the present invention provides a method for producing ABS resin, comprising: S1: adding ABS rubber powder with a water content of no more than 20wt% and other materials to be processed into a screw extruder, and then pushing forward at least a first distance and mixing with molten SAN added to the screw extruder to obtain a first mixed material; S2: heating and exhausting the first mixed material to obtain ABS resin. Using molten SAN directly as a raw material to produce ABS resin reduces the process of remelting SAN after granulation, can reduce power consumption, and reduces the process of remelting molten SAN after granulation, reducing equipment investment and operation control process.

[0045] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 It is a front view and a partial cross-sectional view of an apparatus for producing ABS resin provided by an embodiment of the present invention;

[0048] Figure 2 It is a top view and a partial cross-sectional view of an apparatus for producing ABS resin provided by an embodiment of the present invention;

[0049] Figure 3 is a comparison chart of different numerical ratios of the method for producing ABS resin provided by an embodiment of the present invention;

[0050] Figure 4 yes Figure 1 Schematic diagram of the lead of the screw from the first screw segment to the third screw segment.

[0051] Reference numerals:

[0052] 100, twin-screw extruder; 110, feeding and conveying zone; 111, first barrel; 111-1, first screw segment; 111-2, first feeding port; 112, second barrel; 112-1, second screw segment; 113, third barrel; 113-1, third screw segment; 113-2, second feeding port; 120, plasticizing and mixing zone; 121, fourth barrel; 121-1, fourth screw segment; 122, fifth barrel; 122-1, fifth screw segment; 130, first exhaust section; 131, front section of first exhaust section; 131-1, sixth screw segment; 131-2, first exhaust port; 132, rear section of first exhaust section; 132-1, seventh screw segment; 140, second exhaust section; 141, The front section of the second exhaust section; 141-1, the eighth screw section; 141-2, the first injection port; 142, the rear section of the second exhaust section; 142-1, the ninth screw section; 142-2, the second exhaust port; 150, the third exhaust section; 151, the front section of the third exhaust section; 151-1, the tenth screw section; 151-2, the second injection port; 152, the rear section of the third exhaust section; 152-1, the eleventh screw section; 152-2, the third exhaust port; 160, the pressure building section; 160-1, the twelfth screw section; 170, the motor; 180, the coupling; 190, the reduction box; 200, the side exhaust screw machine; 201, the first side exhaust screw machine; 202, the second side exhaust screw machine; 203, the third side exhaust screw machine. DETAILED DESCRIPTION

[0053] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0054] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "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 embodiments of the present invention 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 embodiments of the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0055] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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 an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0056] In the embodiments of the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0057] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0058] The present invention provides a device for producing ABS resin, the design and application of which mainly focus on the technical field of ABS resin production, aiming to optimize the production process and improve production efficiency. In the traditional production process of ABS resin materials, the treatment of moisture has always been a key link, because moisture may not only affect the quality of the resin, but also may lead to a decrease in production efficiency. In order to effectively solve this problem, the present invention creatively adopts a linkage mechanism between a side exhaust screw machine and a twin-screw extruder. This mechanism can directly gasify the moisture generated in the production process into water vapor by heating, and then directly discharge it through a specific exhaust system, thereby effectively avoiding the potential impact of moisture on the quality of the resin, and also significantly improving the continuity and stability of the production line. The present invention also provides a method for producing ABS resin, directly adding molten ABS as a raw material to a twin-screw extruder, instead of adopting the traditional steps of first preparing SAN particles and then performing melt processing. This change not only simplifies the entire production process, reduces intermediate links and energy consumption, but also makes the use of the equipment more efficient and flexible. Since the molten ABS enters the extruder directly without additional pretreatment steps, the production cycle can be significantly shortened and production efficiency can be improved. The design of the side exhaust screw machine is determined by the design number of exhaust sections of the twin-screw extruder. When the moisture content of the twin-screw extruder feed is too high, several side exhaust screw machines can be set up for exhaust treatment to achieve the purpose of generating the required ABS resin.

[0059] One embodiment of the present invention, in combination with Figure 1 and Figure 2 As shown, an embodiment of the present invention provides an apparatus for producing ABS resin, comprising a twin-screw extruder 100 and at least one side exhaust screw machine 200, wherein the twin-screw extruder 100 is provided with a mandrel and a screw composed of a modular screw element installed on the mandrel, wherein the twin-screw extruder 100 comprises at least one exhaust section, wherein an exhaust port is provided outside the exhaust section, wherein each exhaust port is connected to the side exhaust screw machine 200, wherein the side exhaust screw machine 200 is connected to a motor, wherein the motor can drive the side exhaust screw machine 200 to work, and wherein a screw is provided inside the side exhaust screw machine 200. The side exhaust screw machine 200 can be connected to an exhaust device disposed outside the apparatus of the present invention, and is used to exhaust moisture from the processed material in the twin-screw extruder 100; the screw in the side exhaust screw machine 200 rotates toward one side of the twin-screw extruder 100, and is used to apply pressure to the material toward one side of the twin-screw extruder, so as to prevent the exhaust device from taking out the steam and the material together.

[0060] In this embodiment, the twin-screw extruder 100 includes: a feeding and conveying zone 110, a plasticizing and mixing zone 120, a first exhaust section 130, a second exhaust section 140, a third exhaust section 150 and a pressure building section 160, and the feeding and conveying zone 110, the plasticizing and mixing zone 120, the first exhaust section 130, the second exhaust section 140, the third exhaust section 150 and the pressure building section 160 are connected in sequence. The side exhaust screw machine 200 includes: a first side exhaust screw machine 201, a second side exhaust screw machine 202 and a third side exhaust screw machine 203. The first side exhaust screw machine 201 is connected to the first exhaust section 130, the second side exhaust screw machine 202 is connected to the second exhaust section 140, and the third side exhaust screw machine 203 is connected to the third exhaust section 150. The first side exhaust screw machine 201, the second side exhaust screw machine 202 and the third side exhaust screw machine 203 are respectively used to discharge the moisture heated, gasified and evaporated into steam in the first exhaust section 130, the second exhaust section 140 and the third exhaust section 150.

[0061] It is understood that the twin-screw extruder 100 is a twin-shaft screw machine rotating in the same direction, and the two screws are meshed with each other to form an "8" shape. In this embodiment, the twin screws can transport, melt, plasticize and shear the mixed materials.

[0062] In this embodiment, the feeding and conveying area 110 is composed of a first barrel 111, a second barrel 112 and a third barrel 113 connected in sequence. The first barrel 111 is provided with a first feeding port 111-2, and the first feeding port 111-2 is used to feed the material to be processed. The third barrel 113 is provided with a second feeding port 113-2, and the second feeding port 113-2 is used to feed the melt SAN. The first screw segment 111-1, the second screw segment 112-1 and the third screw segment 113-1 are arranged outside the core shaft of the feeding and conveying area 110, and the first screw segment 111-1, the second screw segment 112-1 and the third screw segment 113-1 correspond to the first barrel 111, the second barrel 112 and the third barrel 113 respectively.

[0063] The plasticizing and kneading zone 120 is composed of a fourth barrel 121 and a fifth barrel 122 connected in sequence, and a fourth screw segment 121-1 and a fifth screw segment 122-1 are arranged outside the core shaft of the plasticizing and kneading zone 120, and the fourth screw segment 121-1 and the fifth screw segment 122-1 correspond to the fourth barrel 121 and the fifth barrel 122 respectively.

[0064] The first exhaust section 130 is composed of a front section 131 of the first exhaust section and a rear section 132 of the first exhaust section, which are connected in sequence. The front section 131 of the first exhaust section is provided with a first exhaust port 131-2, and the first exhaust port 131-2 is connected to the first side exhaust screw machine 201. The sixth screw segment 131-1 and the seventh screw segment 132-1 are arranged outside the core shaft of the first exhaust section 130, and the sixth screw segment 131-1 and the seventh screw segment 132-1 correspond to the front section 131 and the seventh barrel 132 of the first exhaust section, respectively.

[0065] The second exhaust section 140 is composed of a front section 141 of the second exhaust section and a rear section 142 of the second exhaust section connected in sequence, the front section 141 of the second exhaust section is provided with a first injection port 141-2, the first injection port 141-2 is used to add devolatilization-aiding materials, the rear section 142 of the second exhaust section is provided with a second exhaust port 142-2, the second exhaust port 142-2 is connected to the second side exhaust screw machine 202, and an eighth screw segment 141-1 and a ninth screw segment 142-1 are arranged outside the core shaft of the second exhaust section 140, the eighth screw segment 141-1 and the ninth screw segment 142-1 correspond to the front section 141 of the second exhaust section and the rear section 142 of the second exhaust section, respectively.

[0066] The third exhaust section 150 is composed of a front section 151 of the third exhaust section and a rear section 152 of the third exhaust section, which are connected in sequence. The front section 151 of the third exhaust section is provided with two injection ports 151-2, and the second injection ports 151-2 are used to add devolatilization-aiding materials. The rear section 152 of the third exhaust section is provided with a third exhaust port 152-2, and the third exhaust port 152-2 is connected to the third side exhaust screw machine 203. The tenth screw segment 151-1 and the eleventh screw segment 152-1 are arranged outside the core shaft of the third exhaust section 150, and the tenth screw segment 151-1 and the eleventh screw segment 152-1 correspond to the front section 151 of the third exhaust section and the rear section 152 of the third exhaust section, respectively.

[0067] An eleventh screw segment 160 - 1 is disposed outside the core shaft of the pressure building segment 160 .

[0068] Among them, the screw segment outside the core shaft is provided with a conveying thread and a shearing thread. The first screw segment 111-1, the second screw segment 112-1 and the third screw segment 113-1 of the feeding and conveying zone 110 are conveying threads, and the conveying threads here are used to mix the materials and convey them to the plasticizing and mixing zone 120; the fourth screw segment 121-1 and the fifth screw segment 122-1 of the plasticizing and mixing zone 120 are shearing threads, and the shearing threads of the plasticizing and mixing zone 120 are used to chop the materials for fusion to obtain the first mixed material; the sixth screw segment 131-1 and the seventh screw segment 132-1 of the first exhaust section 130 are conveying threads, and the conveying threads here are used to convey the first mixed material to the second exhaust section 140 and obtain the second mixed material; the second exhaust section 1 The eighth screw segment 141-1 of 40 is a shearing thread, and the shearing thread here is used to shear and mix the second mixed material and the devolatilization material added to the second exhaust section 140 to obtain a third mixed material; the ninth screw segment 142-1 of the second exhaust section 140 is a conveying thread, and the conveying thread here is used to convey the third mixed material to the third exhaust section 150; the tenth screw segment 151-1 of the third exhaust section 150 is a shearing thread, and the shearing thread here is used to shear and mix the third mixed material and the devolatilization material added to the third exhaust section 150 to obtain a fourth mixed material; the eleventh screw segment 152-1 of the third exhaust section 150 is a conveying thread, and this conveying thread is used to convey the fourth mixed material to the pressure building section 160.

[0069] In this embodiment, the length of the second barrel 112 is: L1 = (2-8) × D, wherein D is the thread diameter of the twin-screw extruder, preferably (4-6) × D; the length of the first exhaust section 130 is: L2 = (4-10) × D, preferably (6-8) × D; the length of the second exhaust section 140 is: L3 = (4-10) × D, preferably (6-8) × D; the length of the third exhaust section 150 is: L4 = (4-10) × D, preferably (6-8) × D. The length of the pressure-building section 160 is: L5 = (4-10) × D, preferably (4-8) × D. Preferably, the added materials include but are not limited to ABS rubber powder, production aids, recycled ABS particles or recycled SAN. Among them, the production aid is a powder and granular material aid; recycled ABS particles or recycled SAN are added as needed, and may not be added when back-blending is not required.

[0070] See also Figure 4As shown, the lead of the screw element gradually decreases from the first screw segment 111 to the second screw segment 112. The second screw segment 112 generates an extrusion force on the material to compact the material and prevent water vapor from flowing back to the first feeding port through the loose material and thus hindering the feeding. The lead of the screw thread element is the smallest at the connection between the second screw segment 112 and the third screw segment 113. This setting can prevent ABS powder from splashing and can compact the powder material to fully mix it with the molten SAN.

[0071] In this embodiment, the twin-screw extruder 100 is provided with a plurality of side openings. When the twin-screw extruder 100 is working, the side exhaust screw machine 200 can directly discharge the water vapor generated by heating and gasifying the water in the production process according to the processing sequence, thereby avoiding the water vapor blocking the airway and causing shutdown, and can improve production output.

[0072] Among them, the first exhaust port 131-2 is connected to the first side exhaust screw machine 201, the first injection port 141-2 is used to add devolatilization materials, the second exhaust port 142-2 is connected to the second side exhaust screw machine 202, the second injection port 151-2 is used to add devolatilization materials, and the third exhaust port 152-2 is connected to the third side exhaust screw machine 203.

[0073] More preferably, the side exhaust screw machine 200 is connected to a motor, which drives the side exhaust screw machine 200 to rotate in the direction of the twin-screw extruder 100. When material enters the side exhaust screw machine 200, the screw in the side exhaust screw machine 200 generates pressure on the material in the direction of the twin-screw extruder 100. At this time, steam is discharged from the side exhaust screw machine 200, and the material can return to the twin-screw extruder 100 along the movement direction of the screw of the side exhaust screw machine 200, thereby preventing material overflow, ensuring production stability, and improving output and product quality.

[0074] Another embodiment of the present invention provides a method for producing ABS resin, comprising:

[0075] S1: adding ABS rubber powder with a water content of no more than 20 wt% and other materials to be processed into a twin-screw extruder 100, and then pushing forward at least a first distance and mixing with the melted SAN added to the screw extruder to obtain a first mixed material;

[0076] The pushing process mixes and compacts the materials; the first distance L2 = (4-10) × D, where D is the thread diameter of the twin-screw extruder 100;

[0077] S2: The first mixed material is heated and degassed to obtain ABS resin.

[0078] Specifically, step S1 also includes:

[0079] S11: feeding ABS rubber powder with a water content not exceeding 20wt% and other materials to be processed into the first cylinder 111 of the feeding and conveying area 110 through the first feeding port 111-2;

[0080] S12: transporting ABS rubber powder with a water content of no more than 20 wt% and other materials to be processed through the second cylinder 112 to the third cylinder 113;

[0081] S13: The molten SAN is fed into the third cylinder 113 through the second feeding port 113-2, and is transported to the plasticizing and kneading zone 120 with the ABS rubber powder and other materials to be processed to be melted and mixed to obtain a first mixed material.

[0082] Specifically, step S2 also includes:

[0083] The first mixed material is heated in the exhaust section to evaporate the water in the first mixed material and exhaust steam through the side exhaust screw machine 200 to obtain ABS resin. At the same time, the screw of the side exhaust screw machine 200 returns the first mixed material taken out of the steam to the exhaust section.

[0084] Among them, the materials to be processed include but are not limited to production additives, recycled ABS particles or recycled SAN; the devolatilization materials include but are not limited to devolatilization water, the injection amount of the devolatilization water is 0.4wt% to 0.6wt% of the ABS resin output and the water temperature does not exceed 60°C.

[0085] In this embodiment, the exhausting of steam in step S2 includes: the first exhaust section 130 exhausts steam through the first side exhaust screw machine 201 to obtain a second mixed material;

[0086] The second exhaust section 140 adds devolatilization aid material through the first injection port 141-2, the second mixed material and the devolatilization aid material are mixed through the shearing screw of the front section 141 of the second exhaust section, and the second side exhaust screw machine 202 discharges steam to obtain a third mixed material;

[0087] The third exhaust section 150 adds devolatilization materials through the second injection port 151-2, and the third mixed material and the devolatilization materials are mixed through the shearing screw of the front section 151 of the third exhaust section. The third side exhaust screw machine 203 discharges steam to obtain ABS resin and transmits the ABS resin to the pressure building section 160 through the conveying screw.

[0088] In this embodiment, ABS rubber powder is added into the twin-screw extruder 100 through the first feeding port 111-2, and is conveyed into the third barrel 113 after being compressed by the second screw segment 112-1. The melt SAN is put into the second feeding port 113-2, and is conveyed to the plasticizing and mixing zone 120 of the third screw segment 113-1. ABS rubber powder with a moisture content of up to 20wt% can be used.

[0089] More preferably, when back-blending is required, recycled SAN or recycled ABS particles can be added, and the maximum back-blending amount can reach 20% of the total output.

[0090] In this embodiment, the devolatilization materials include but are not limited to devolatilization water. The weight ratio and temperature of the devolatilization water have an impact on the residual monomer content of the final ABS resin. The best effect is achieved when the water injection amount is 0.4wt% to 0.6wt% of the total ABS resin output and the water temperature is 50°C to 60°C.

[0091] It is understood by those skilled in the art that when molten SAN is added, a large amount of steam will flow back to the feed port when ABS rubber powder and molten SAN are in contact. The feed port will cause problems such as powder agglomeration, pipe blockage, condensed water, etc. due to a large amount of water vapor. In the method for producing ABS resin provided by the present invention, ABS rubber powder is added first and then molten SAN is added, and a screw with a large lead and compression ratio is designed to compact the ABS rubber powder. At this time, due to the feeding of ABS rubber powder, the steam cannot return to the feed port, causing blockage and shutdown, and the first feed port 111-2 can be kept dry and cooled. In this method, the length requirement for the second barrel 112 is L1=(2~8)×D, where D is the thread diameter of the twin-screw extruder. When considering the economic performance and process requirements, L1=(4~6)×D is the most preferred; this method can also avoid further processing of the molten SAN, and can simplify the process steps.

[0092] The moisture content of the ABS rubber powder fed from the first feeding port 113 - 2 may be 0wt% to 20wt%.

[0093] In this embodiment, the plasticizing and mixing zone 120 completely plasticizes and mixes the ABS rubber powder with the melted SAN, and at this time, there should be no unmelted solid state material at the outlet of the plasticizing and mixing zone 120. When the first feeding port 113-2 is simultaneously fed with recycled SAN or production aids, a maximum of 20wt%*the total amount of ABS resin produced can be recycled.

[0094] In this embodiment, the first exhaust section 130 is mainly used to discharge the steam generated by the vaporization of water contained in the raw material, and keep the raw material inside the twin-screw extruder 100 without spraying out. The first exhaust port 131-2 with a side opening is designed at the front section 131 of the first exhaust section of the first exhaust section 130 and cooperates with the first side screw exhauster 201 to exhaust the steam and prevent the material from being taken out. The pipeline connected to the first side screw exhauster 201 uses an exhaust device to suck away the continuous steam. The exhaust device includes but is not limited to a vacuum system. The exhaust working method includes but is not limited to vacuum suction or fan suction. According to the size of the exhaust volume, the first vacuum can be freely adjusted between 0kPaA and 100kPaA. At the rear section 132 of the first exhaust section of the first exhaust section 130, the material is continuously refurbished to continue to gasify and discharge the water in the raw material. The specific position and quantity of the first side screw exhauster 201 connected to the first exhaust section 130 are not limited, and in some cases, exhaust can be carried out by non-exhaust machine. At this time, the length of the first exhaust section 130 is: L2 = (4-10) × D, wherein D is the screw diameter of the twin-screw extruder, and more preferably, L2 = (6-8) × D.

[0095] In this embodiment, the second exhaust section 140 is mainly used to discharge the remaining water vapor after passing through the first exhaust section 130 and the residual small molecular monomers in the raw materials. Using the principle of bubbling devolatilization, the front section 141 of the second exhaust section of the second exhaust section 140 is injected with devolatilizer water, and the best effect is achieved when the total ABS resin output is 0.4-0.6wt% and the water temperature is 50-60°C. The devolatilizer can also be a small molecule substance that does not participate in the reaction and is easily gasified, such as nitrogen and carbon dioxide. After water injection, it is fully mixed with the molten ABS resin for renovation. It is sent to the rear section 142 of the second exhaust section of the second exhaust section 140. The rear section 142 of the second exhaust section of the second exhaust section 140 is designed with a second exhaust port 142-2 with a side opening and cooperates with a second side screw exhauster 202 to discharge the steam and prevent the material from being taken out together. The pipeline connected to the second side screw exhauster 202 uses vacuum suction to suck away the continuous steam. According to the exhaust volume, the second vacuum can be freely adjusted between 0kPaA and 50kPaA. The specific position and quantity of the second side screw exhauster 202 of the second exhaust section 140 are not limited. In some cases, exhaust can also be performed by non-exhaust machine. The length of the second exhaust section is: L3 = (4-10) × D, where D is the thread diameter of the twin-screw extruder, and more preferably, L3 = (6-8) × D.

[0096] In this embodiment, the third exhaust section 150 is mainly used to discharge the remaining water and small molecular monomers remaining in the raw materials after passing through the second exhaust section 140. Using the principle of bubbling devolatilization, the front section 151 of the third exhaust section of the second exhaust section 150 is injected with devolatilizer water, and the best effect is achieved when the total ABS resin output is 0.4wt% to 0.6wt% and the water temperature is 50 to 60°C. The devolatilizer can also be a small molecule substance that does not participate in the reaction and is easily gasified, such as nitrogen and carbon dioxide. After water injection, it is fully mixed with the molten ABS resin for renovation. It is sent to the rear section 152 of the third exhaust section of the third exhaust section 150. The rear section 152 of the third exhaust section of the third exhaust section 150 is designed with a third exhaust port 152-2 with a side opening and cooperates with a third side screw exhauster 203 to discharge steam and prevent the material from being taken out together. The pipeline connected to the third side screw exhauster 203 uses vacuum suction to suck away the continuous steam. According to the exhaust volume, the third vacuum can be freely adjusted between 0kPaA and 20kPaA. The specific position and quantity of the third side screw exhauster 203 of the third exhaust section 150 are not limited. In some cases, exhaust can also be performed by non-exhaust machine. The length of the third exhaust section 150 is: L4 = (4-10) × D, where D is the screw diameter of the twin-screw extruder, and more preferably, L4 = (6-8) × D.

[0097] In this embodiment, the pressure building section 160 pushes the mixed and degassed ABS resin melt to the downstream pressurization, filtering and granulation equipment. The length of the pressure building section is: L5 = (4-10) × D, where D is the thread diameter of the twin-screw extruder. More preferably, L5 = (4-8) × D.

[0098] Among them, the front section 131 of the first exhaust section, the rear section 142 of the second exhaust section and the rear section 152 of the third exhaust section are heated and the temperature of the front section 131 of the first exhaust section can reach 220-300°C, and the rear section 142 of the second exhaust section and the rear section 152 of the third exhaust section increase by 20-30°C respectively.

[0099] See also Figure 3 As shown, other embodiments of the present invention produce ABS resin by adding back-doped SAN particles with different numerical ratios, including:

[0100] Step 1: Use a vector weight metering device to continuously and stably feed the SAN melt after it is completely melted by a melting device into the second feeding port 113-2 of the twin-screw extruder 100 according to the total formula ratio of 74%, 64%, and 54% (corresponding to 0%, 10%, and 20% of the back-doped SAN particles);

[0101] Step 2: ABS wet powder containing 18% moisture, production aids, and back-mixed SAN particles are continuously and stably fed into the first feeding port 111-2 of the twin-screw extruder 100 according to the total formula ratio of 25% (dry weight): 1%: 0%, 10%, and 20% by using a vector weight metering device. The materials are conveyed and compressed by the first screw segment 111-1 and the second screw segment 112-1 in the first barrel 111 and the second barrel 112, and then enter the third barrel 113 to start mixing with the SAN melt 2.

[0102] Step 3: SAN melt, ABS wet powder with 18% moisture, production additives, and back-doped SAN particles enter the plasticizing and kneading zone 130, and the components are preliminarily mixed in the fourth barrel 121 and the fifth barrel 122 and the fourth screw segment 121-1 and the fifth screw segment 122-1 inside to obtain a preliminary ABS melt containing more moisture.

[0103] Step 4: The ABS melt containing more water continues to be fed into the first exhaust section 130, and passes through the front section 131 of the first exhaust section and the rear section 132 of the first exhaust section successively. The ABS melt is efficiently refurbished by the sixth screw section 131-1 and the seventh screw section 132-1, and the internal water and residual monomers are refurbished to the surface of the melt and then vaporized into steam. The steam enters the first side exhaust screw machine 201 through the first exhaust port 131-2 located on the front section 131 of the first exhaust section, and is extracted by the vacuum equipment with a vacuum pressure of 100 kPaA. Most of the water is separated here.

[0104] Step 5: The ABS melt is continuously sent to the second exhaust section 140 by the seventh screw segment 132-1. In the front section 141 of the second exhaust section of the second exhaust section 140, the eighth screw segment 141-1 continues to mix the ABS melt, and at the same time, the devolatilizer water can be injected at the first injection port 141-2 of the front section 141 of the second exhaust section, with a water temperature of 55°C and an injection flow rate of 0.5% of the total output, and is injected into the eighth screw segment 141-1 to be fully mixed with the ABS melt; in the rear section 142 of the second exhaust section of the second exhaust section 140, the ninth screw segment 142-1 efficiently renovates the ABS melt, renovates the internal moisture and residual monomers to the melt surface, and then vaporizes into steam, and the steam enters the second side exhaust screw machine 202 through the second exhaust port 142-2 located on the rear section 142 of the second exhaust section, and is evacuated by the vacuum equipment, and the vacuum pressure is 10kPaA, and the separation of the remaining moisture and residual monomers is completed here.

[0105] Step 6: The ABS melt is continuously sent from the ninth screw segment 142-1 to the third exhaust segment 150. In the front section 151 of the third exhaust segment 150, the ABS melt is continuously mixed by the tenth screw segment 151-1. Meanwhile, the devolatilizer water can be injected at the second injection port 151-2 of the front section 151 of the third exhaust segment. The water temperature is 55°C and the injection flow rate is 0.5% of the total output. The water is injected into the tenth screw segment 151-1 to be fully mixed with the ABS melt. In the rear section 152 of the third exhaust segment, the ABS melt is efficiently refurbished by the eleventh screw segment 152-1. The internal moisture and residual monomers are refurbished to the surface of the melt and then gasified into steam. The steam enters the second side exhaust screw machine 202 through the third exhaust port 152-2 located on the rear section 152 of the third exhaust segment and is extracted by the vacuum equipment. The vacuum pressure is 10kPaA. The separation of all moisture and residual monomers is completed here.

[0106] Step 7: The pure ABS melt is pushed to the pressure building section 160 by the eleventh screw segment 152-1. The pure ABS melt is conveyed and pressurized by the pressure building section 160 and the internal twelfth screw segment 160-1, so that the material can smoothly enter the downstream pelletizing device, and finally produce ABS resin with excellent comprehensive performance.

[0107] Finally, it should be noted that the above implementation modes are only used to illustrate the technical solutions of the present invention, rather than to limit the present invention. Although the present invention is described in detail with reference to the embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of this application.

Claims

1. A device for producing ABS resin, characterized in that: include: A twin screw extruder and at least one side venting screw machine; The twin-screw extruder is provided with a screw composed of a mandrel and a modular screw element mounted on the mandrel, and the twin-screw extruder includes at least one exhaust section; The at least one exhaust section is respectively connected to a side exhaust screw machine, and a screw is arranged inside the side exhaust screw machine; The screw in the side exhaust screw machine rotates toward one side of the twin-screw extruder, and the screw is used to apply pressure to the material toward one side of the twin-screw extruder.

2. The equipment for producing ABS resin according to claim 1, characterized in that: The exhaust section is correspondingly provided with an exhaust port, and the side exhaust screw machine is connected with the twin-screw extruder through the exhaust port.

3. The equipment for producing ABS resin according to claim 1, characterized in that: The twin-screw extruder also includes: a feeding and conveying zone, a plasticizing and mixing zone, and a pressure building section; The feeding and conveying zone, the plasticizing and mixing zone, the at least one exhaust section and the pressure building section are connected in sequence.

4. The equipment for producing ABS resin according to claim 3, characterized in that: The feeding and conveying area is composed of a first cylinder, a second cylinder and a third cylinder connected in sequence; The first cylinder is provided with a first feeding port, and the first feeding port is used to feed ABS rubber powder and other materials to be processed; The third cylinder is provided with a second feeding port, and the second feeding port is used for feeding the melt SAN.

5. The equipment for producing ABS resin according to claim 4, characterized in that: The length of the second cylinder is: , where D is the diameter of the screw element of the twin-screw extruder.

6. The equipment for producing ABS resin according to claim 4, characterized in that: The lead of the thread of the corresponding mandrel in the second cylinder gradually decreases, and the ratio of the maximum lead divided by the minimum lead, that is, the compression ratio, is not less than 1.

5.

7. The equipment for producing ABS resin according to claim 3, characterized in that: The plasticizing and mixing zone is composed of a plurality of cylinders connected in sequence.

8. The equipment for producing ABS resin according to claim 3, characterized in that: The exhaust section is composed of a front section and a rear section connected in sequence; The front section is provided with an injection port, and the injection port can be used to add devolatilization-aiding materials; The exhaust port is opened on the rear section.

9. The equipment for producing ABS resin according to claim 8, characterized in that: The devolatilization materials include but are not limited to devolatilization water. The injection amount of the devolatilization water is 0.4 wt% to 0.6 wt% of the ABS resin output and the water temperature does not exceed 60°C.

10. The equipment for producing ABS resin according to claim 1, characterized in that: The length of the exhaust section is: , where D is the diameter of the screw element of the twin-screw extruder.

11. The equipment for producing ABS resin according to claim 3, characterized in that: The length of the pressure building section is: , where D is the diameter of the screw element of the twin-screw extruder.

12. The equipment for producing ABS resin according to claim 1, characterized in that: The threaded element comprises a conveying thread and a shearing thread; The conveying screw thread is arranged in the feeding and conveying area, the rear section of the exhaust section and the pressure building section; The shearing threads are arranged in the plasticizing and mixing zone and the front section of the exhaust section, and the shearing threads are used for shearing and mixing materials.

13. The equipment for producing ABS resin according to claim 1, characterized in that: The materials include but are not limited to ABS rubber powder, melt SAN, production aids, recycled ABS particles or recycled SAN.

14. The equipment for producing ABS resin according to claim 13, characterized in that: The water content of the ABS rubber powder particles does not exceed 20wt%.

15. The equipment for producing ABS resin according to claim 13, characterized in that: The amount of recycled ABS particles and recycled SAN does not exceed 20%.

16. A method for producing ABS resin, characterized in that: The device for producing ABS resin according to any one of claims 1 to 15, comprising: S1: adding ABS rubber powder with a water content of no more than 20wt% and other materials to be processed into a twin-screw extruder, and then advancing the powder forward for at least a first distance and mixing the powder with the melt SAN added into the screw extruder to obtain a first mixed material; The advancing process causes the materials to be mixed and compacted; the first distance , where D is the diameter of the screw element of the twin-screw extruder; S2: The first mixed material is heated and degassed to obtain ABS resin.

17. The method for producing ABS resin according to claim 16, characterized in that: The method for preparing the first mixed material, step S1, comprises: S11: feeding ABS rubber powder with a water content not exceeding 20wt% and other materials to be processed into the first cylinder of the feeding and conveying area through the first feeding port; S12: transporting ABS rubber powder with a water content not exceeding 20wt% and other materials to be processed through the second cylinder to the third cylinder; S13: The molten SAN is fed into the third cylinder through the second feeding port, and is transported to the plasticizing and kneading zone together with the ABS rubber powder and other materials to be processed, and is uniformly kneaded by shearing to obtain a first mixed material.

18. The method for producing ABS resin according to claim 16, characterized in that: The step S2 further includes: The first mixed material is connected to a vacuum system in the exhaust section, and the moisture in the first mixed material is evaporated by external heating and shear heat generation, and the steam is discharged through the side exhaust screw machine to obtain ABS resin. At the same time, the screw of the side exhaust screw machine returns the first mixed material taken out of the steam to the exhaust section.

19. The method for producing ABS resin according to claim 18, characterized in that: The vacuum system pressure is 0 kPaA-100 kPaA.

20. The method for producing ABS resin according to claim 18, characterized in that: The devolatilization materials include but are not limited to devolatilization water. The injection amount of the devolatilization water is 0.4 wt% to 0.6 wt% of the ABS resin output and the water temperature does not exceed 60°C.

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