Based on supercritical CO 2 Is characterized in that the desulfurization equipment is extruded in succession to integrated single screw rod
Technical Field
The present invention relates to the utilization of supercritical CO 2 Preparation of reclaimed rubber, in particular to a method based on supercritical CO 2 Is an integrated single screw continuous extrusion desulfurization device.
Background
At present, the mature process for producing reclaimed rubber is a high-temperature high-pressure dynamic desulfurization method, and the process methods of preparing reclaimed rubber by utilizing continuous desulfurization equipment of a screw extruder, preparing reclaimed rubber by utilizing screw equipment and the like are also similar to those of spring bamboo shoots after rain, but are all based on the traditional process formula. With the continuous increase of the environmental protection of the country, the three-waste treatment in the rubber industry becomes a difficult problem of environmental protection and whole. The environmental protection problem can be thoroughly solved only by changing the method and the process for processing reclaimed rubber. At present, a related patent of a supercritical carbon dioxide auxiliary waste rubber regeneration process exists, and patent CN105085977A proposes a supercritical fluid auxiliary single screw rubber regeneration sulfur-breaking regeneration method, wherein a single screw shearing action is used as a core, electromagnetic heating is used as a heat source, and swelling and permeability of the supercritical carbon dioxide are utilized to obtain regenerated rubber, but actual operability is not strong.
When the temperature of the carbon dioxide exceeds 31 ℃ and the pressure exceeds 7.38MPa, the supercritical state is entered. The sealing element is under the pressure of 0.4MPa, so the sealing performance of the whole equipment is extremely high.
Disclosure of Invention
The invention aims to solve the problems in the prior art, and provides an integrated single-screw continuous extrusion desulfurization device based on supercritical CO2, which prevents high-pressure gas in the device from leaking out, ensures the constant pressure in the device and ensures the stability of the whole process.
The technical scheme of the invention is as follows: supercritical CO-based 2 The integrated single-screw continuous extrusion desulfurization equipment comprises a base, a transmission device, a feeding section machine barrel and an extruder head, wherein the transmission device, the feeding section machine barrel and the extruder head are sequentially arranged on the base, and the main screw is connected with the transmission device through the feeding section machine barrel and the desulfurization section machine barrel;
the feeding section machine barrel comprises a machine barrel body and a bushing, wherein the bushing is fixed on the inner surface of the machine barrel body, a main screw rod is arranged in the bushing, a sealing sleeve is fixed between the shaft end of the main screw rod connected with a transmission device and a transmission device shell, the end part of the sealing sleeve is respectively contacted with the end surface of the machine barrel body and the end surface of the bushing, a groove is formed in the inner side of the sealing sleeve and corresponds to the shaft shoulder of the end part of the main screw rod, and a extrusion type sealing ring is arranged in the groove;
the second-order feeding device comprises a first-order feeding structure and a second-order feeding structure, and the first-order feeding structure is connected with the second-order feeding structure through a flange;
the first-order feeding mechanism comprises a connecting sleeve I, a first-order machine barrel, a first-order screw rod and a connecting sleeve II, wherein the connecting sleeve I, the first-order machine barrel and the connecting sleeve II are sequentially and fixedly connected, the connecting sleeve II is fixedly connected with a machine barrel body, the first-order screw rod penetrates through the connecting sleeve I and the first-order machine barrel, an anti-reversion ring is arranged on the annular outer side of the head part of the first-order screw rod, two limiting rings are arranged on the inner surface of the connecting sleeve II, the anti-reversion ring is arranged between the two limiting rings, a spring is arranged between the anti-reversion ring and the limiting ring, a groove is formed in the inner wall of the joint of the connecting sleeve I and the first-order machine barrel, and a sealing ring I is arranged in the groove;
the second-order feeding structure comprises a second-order screw rod, a connecting sleeve III and a second-order machine barrel, one end of the second-order machine barrel is fixedly connected with the connecting sleeve III, the other end of the second-order machine barrel is fixedly connected with the first-order machine barrel, the second-order screw rod penetrates through the connecting sleeve III and the second-order machine barrel, a groove is formed in the connecting position of the connecting sleeve III and the second-order machine barrel and located in the inner surface of the connecting sleeve III, and a sealing ring II is arranged in the groove.
An air inlet and a heating medium inlet and outlet are arranged on the desulfurization section machine barrel, and CO in the air storage tank is discharged from the desulfurization section machine barrel 2 Pressurizing to the required pressure by a pressurizing device, wherein a cooling medium inlet and a cooling medium outlet are arranged on the feeding section machine barrel.
The main screw adopts barrel pin screw rod, and the several row pin hole on the desulfurization section barrel is equipped with the slot tangent with the screw rod base diameter on the main screw rod that corresponds, and the pin passes pin hole and inserts the slot of main screw rod in, and the air inlet setting is in pin department, the built-in through-hole of pin that is equipped with the air inlet, and the through-hole is connected with supercritical carbon dioxide admission line, and supercritical carbon dioxide gets into in this extrusion equipment along the passageway in the pin to in the rubber powder permeates fast.
The first-order feeding mechanism further comprises a gear motor I, the gear motor I drives the first-order screw rod to rotate in the first-order machine barrel through a key I, and a shaft sleeve I and a bearing I are arranged between the shaft end of the first-order screw rod connected with the gear motor I and the connecting sleeve I.
The second-order feeding structure further comprises a gear motor II, the gear motor drives the second-order screw rod to rotate in the second-order machine barrel through a key II, a shaft sleeve II and a bearing II are arranged between the shaft end of the second-order screw rod, which faces the gear motor, and the connecting sleeve III, and the second-order machine barrel is connected with the rubber powder feeding port.
The beneficial effects of the invention are as follows:
(1) The supercritical CO2 is applied to desulfurization regeneration of the rubber powder of the waste tires, so that a chemical softener used in the desulfurization process is replaced, and the content of toxic and harmful substances such as polycyclic aromatic hydrocarbon in the reclaimed rubber is reduced;
(2) By arranging the first-order screw mechanism and the second-order screw mechanism, continuous and stable forward transmission of materials is realized under the rotation action of the first-order screw and the second-order screw, so that continuous and stable feeding is ensured;
(3) By arranging the anti-return ring in the first-order screw mechanism, the rubber material can be effectively prevented from returning to the second-order feeding device along with high-pressure gas;
(4) By arranging the sealing devices in the feeding section machine barrel, the first-order screw mechanism and the second-order screw mechanism, a small amount of high-pressure gas can be effectively prevented from flowing into the reduction gearbox and the feeding port, the pressure in the equipment is effectively prevented from being reduced, and the constant pressure in the equipment is ensured;
(5) The supercritical carbon dioxide enters the extrusion equipment through the central through hole of the pin, so that the position of the air inlet can be changed according to the process requirement, and meanwhile, the supercritical carbon dioxide can be quickly permeated into the rubber powder.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a schematic diagram of a second order feeding arrangement;
FIG. 3 is a cross-sectional view of a feed section barrel;
FIG. 4 is a cross-sectional view of a first order feeding mechanism;
FIG. 5 (a) is a schematic diagram of the normal feed station of the anti-reversion loop;
FIG. 5 (b) is a schematic structural view of a reverse flow station of the return-preventing ring;
FIG. 6 is a cross-sectional view of a second order feeding mechanism.
In the figure: 1, a base; 2 a transmission device; 3, feeding a section of machine barrel; 31 machine barrel body; 32 bushings; 33 sealing sleeves; 34 extrusion type sealing rings; a second-order feeding device; 41 first-order feeding mechanism; 411 gear motor I; 412 connecting sleeve i; 413 first stage barrels; 414 first-stage screw; 415 anti-reversion ring; 416 connecting sleeve II; 417 seal ring I; 418 sleeve i; 419 bearing i; 4110 bond I; a 42 second-order feeding mechanism; 421 reducing motor II; 422 connecting sleeve III; 423 second-order barrels; 424 second order screw; 425 seal ring II; 426 sleeve ii; 427 bearing II; 428 bond II; 5 desulfurizing section cylinder; 6, a main screw; 7, extruding a machine head; 101 air inlets; 102 cooling medium inlet and outlet; 103 heating medium inlet and outlet; 104 pin holes; 110 carbon dioxide gas storage tanks; 111 pressurizing means.
Detailed Description
The foregoing objects, features and advantages of the invention will be more readily apparent from the following detailed description of the invention taken in conjunction with the accompanying drawings.
In the following description, specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than those herein described, and those skilled in the art may readily devise numerous other arrangements that do not depart from the spirit of the invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.
The invention relates to a supercritical CO-based catalyst 2 The integrated single-screw continuous extrusion desulfurization equipment comprises a base 1, a transmission device 2, a second-order feeding device 4, a feeding section machine barrel 3, a desulfurization section machine barrel 5 and an extruder head 7, wherein the transmission device 2 comprises a motor, a coupling and a reduction gearbox. The transmission device 2, the second-order feeding device 4, the feeding section cylinder 3, the desulfurization section cylinder 5 and the extruder head 7 are sequentially arranged on the base 1, a main screw rod 6 is arranged in the desulfurization section cylinder 5 and the feeding section cylinder 3, the main screw rod 6 penetrates through the feeding section cylinder 3 and the desulfurization section cylinder 5 to be matched with a hollow shaft of a reduction gearbox, and a motor drives the main screw rod 6 to rotate in the feeding section cylinder 3 and the desulfurization section cylinder 5 through a coupler and the reduction gearbox. One end of the desulfurization section cylinder 5 is fixedly connected with the machine head 7 through a flange, and the other end of the desulfurization section cylinder 5 is fixedly connected with the feeding section cylinder 3 through a flange.
The main screw 6 adopts a machine barrel pin screw, a plurality of rows of pin holes 104 are arranged on the machine barrel 5 of the desulfurization section, grooves tangential to the bottom diameter of the screw are correspondingly formed in the main screw, and pins penetrate through the pin holes 104 and are inserted into the grooves of the main screw. An air inlet 101 and a heating medium inlet and outlet 103 are arranged on the machine barrel 5 of the desulfurization section, and CO in an air storage tank 110 2 Pressurizing to the required pressure by a pressurizing device 111, entering the desulfurization section cylinder 5 through an air inlet 101, and ensuring the temperature stability of the rubber powder desulfurization process by the desulfurization section cylinder 5 through a heating medium inlet and outlet 103And (5) setting. The cooling medium inlet and outlet 102 is arranged on the feeding section cylinder 3, the temperature stability of the fed rubber powder is ensured through the cooling medium inlet and outlet 102, and the heat exchange is completed through the circulation of the medium, so that the temperature stability of the whole process is ensured. The air inlet 101 is arranged at the pin, a through hole is arranged in the pin, the channel is connected with an air inlet pipe of supercritical carbon dioxide, and the supercritical carbon dioxide enters the device along the through hole in the pin, so that the supercritical carbon dioxide can quickly permeate into the rubber powder.
When the supercritical carbon dioxide inlet pressure is greater than a certain value, the pressure maintaining effect of the device is poor. The reason for this is that: first, supercritical carbon dioxide can blow-by to a reduction gearbox; second, supercritical carbon dioxide can blow-by gas to the feed inlet, causing depressurization and difficulty in feeding.
In order to prevent the supercritical carbon dioxide from blowby gas to the reduction gearbox, a sealing sleeve and a sealing ring are arranged between the main screw 6 and the barrel body of the machine barrel. As shown in fig. 3, the feeding section barrel 3 comprises a barrel body 31 and a bushing 32, the bushing 32 is fixed on the inner surface of the barrel body 31, the main screw 6 is arranged in the bushing 32, a sealing sleeve 33 is fixed between one end of the main screw 6 connected with the transmission device 2 and the transmission device shell, one end of the sealing sleeve 33 is respectively contacted with the end face of the barrel body 31 and the end face of the bushing 32, a groove is formed in the inner side of the sealing sleeve 33 and corresponds to the shaft shoulder of the end part of the main screw, and a extrusion type sealing ring 34 is arranged in the groove. The seal sleeve 33 can prevent most of the supercritical carbon dioxide from being leaked out, but a small amount of supercritical carbon dioxide still exists due to the relative rotation between the seal sleeve 33 and the main screw 6, and at this time, the second blocking is performed by the extrusion type seal ring 34. The groove of the sealing ring 34 in the sealing sleeve is pre-extruded, when supercritical carbon dioxide blows air to the reduction gearbox, the extrusion type sealing ring 34 seals the shaft shoulder of the main screw 6, and the generated pressure extrudes the sealing ring 34 again, so that the purpose of sealing a gap by the sealing ring 34 is achieved.
In order to prevent the supercritical carbon dioxide from blowby to the feeding port, the feeding device in the invention is a second-order feeding device. As shown in fig. 2, the second-order feeding device 4 in the present invention includes a first-order feeding structure 41 and a second-order feeding structure 42, and the first-order feeding structure 41 and the second-order feeding structure 42 are connected by a flange. The rubber powder is conveyed to a feeding port by a feeding screw, and the entered rubber powder is respectively transferred to a feeding section machine barrel 3 through a second-order feeding structure 42 and a first-order feeding structure 41 and is extruded by an extruder head 7 through a main screw 6.
As shown in fig. 4, the first-stage feeding mechanism 41 includes a gear motor i 411, a connecting sleeve i 412, a first-stage cylinder 413, a first-stage screw 414 and a connecting sleeve ii 416, wherein the connecting sleeve i 412, the first-stage cylinder 413 and the connecting sleeve ii 416 are sequentially and fixedly connected, the connecting sleeve ii 416 is fixedly connected with the cylinder body 31 of the feeding section cylinder 3 through a connecting sleeve iv, and the first-stage screw 414 passes through the connecting sleeve i 412 and the first-stage cylinder 413. The gear motor I411 drives the first-stage screw 414 to rotate in the first-stage machine barrel 413 through a key I4110, and a shaft sleeve I418 and a bearing I419 are arranged between the shaft end of the first-stage screw 414 connected with the gear motor I411 and the connecting sleeve I412. One side of the head of the first-stage screw 414 is provided with a return-preventing ring 415, the inner surface of the connecting sleeve II 416 is provided with two limiting rings, the return-preventing ring 415 is arranged between the two limiting rings, and a spring is arranged between the return-preventing ring 415 and one of the limiting rings. The first-stage screw 414 has a certain compression ratio, and after the rubber powder is fed, high extrusion pressure is easily built up in the machine head, so that the anti-return ring 415 is pushed to move downwards to the station in fig. 5 (a), and continuous and stable feeding can be realized. When the supercritical carbon dioxide pressure is too high to cause the air flow to flow back, the backflow prevention ring 415 is pushed up to the position of fig. 5 (b), and at this time, the backflow prevention of the rubber powder can be realized. When the gas pressure is reduced, the anti-return ring 415 automatically resets under the action of the spring force of the spring.
The inner wall of the junction of the connecting sleeve I412 and the first-order machine barrel 413 is provided with a groove, a sealing ring I417 is arranged in the groove, and the sealing ring I417 is an extrusion type sealing ring. When a small amount of high-pressure gas returns to the first-stage screw rod, the high-pressure gas generates extrusion force on the sealing ring I417, and the extrusion sealing ring 424 is firmly extruded at the joint of the connecting sleeve I412 and the first-stage machine barrel 413, so that the joint is sealed, and the gas sealing effect is realized.
The second-order feeding structure 42 is shown in fig. 6, and comprises a gear motor II 421, a second-order screw 424, a connecting sleeve III 422 and a second-order machine barrel 423, wherein one end of the second-order machine barrel 423 is fixedly connected with the connecting sleeve III 422, and the other end of the second-order machine barrel 423 is fixedly connected with the first-order machine barrel. The second-order screw rod 424 passes through the connecting sleeve III 422 and the second-order machine barrel 423, the gear motor 421 drives the second-order screw rod 424 to rotate in the second-order machine barrel 423 through the key II 428, a shaft sleeve II 426 and a bearing II 427 are arranged between the shaft end of the second-order screw rod 424, which faces the gear motor 421, and the connecting sleeve III 422, the connecting position of the connecting sleeve III and the second-order machine barrel 423 and the inner surface of the connecting sleeve III 422 are provided with grooves, a sealing ring II 425 is arranged in each groove, and the sealing ring II 425 is an extrusion sealing ring and is in an extrusion state when placed in each groove. Under the action of the anti-return ring 415 and the sealing ring I417 in the first-order feeding mechanism, most of supercritical carbon dioxide gas is blocked, if a small amount of high-pressure gas flows back to the second-order feeding mechanism, the pressure of the high-pressure gas generates extrusion force on the sealing ring II 425, at the moment, the sealing ring II 425 is firmly extruded in a groove of the connecting sleeve III 422, the sealing effect is achieved on the joint of the connecting sleeve III 422 and the second-order machine barrel 423, and the gas sealing effect is achieved. The second-order cylinder 423 is connected with a rubber powder feeding port.
The working process of the invention is as follows: when the equipment acts, the carbon dioxide gas in the carbon dioxide gas storage tank is pressurized to a required pressure value through the pressurizing device, enters the desulfurization section cylinder 5 through the gas inlet 101, enters the desulfurization section cylinder 5 through the feeding port through the second-order feeding mechanism 42, the first-order feeding mechanism 41 and the feeding section cylinder 3 in sequence, circulates in the equipment through the heating medium inlet and outlet, heats the equipment, circulates in the equipment through the cooling medium inlet and outlet, cools the equipment, and ensures that the temperature of the equipment is kept constant, thereby ensuring that the temperature of the material is constant. In addition, through setting up sealing device in feed section barrel, first order feed mechanism, second order feed mechanism, prevent that the high-pressure gas in the desulfurization section barrel from scurring into reducing gear box and feed inlet, guarantee the constancy of pressure in the whole equipment, guaranteed the constancy of temperature and the pressure of whole equipment, make carbon dioxide fully permeate, swell the material, cut and promote the material through main screw rod 6 until the material is carried to extrusion head 7 department by main screw rod 6 and extrudes.
The supercritical CO based method provided by the invention 2 The integrated single screw continuous extrusion desulfurization equipment is described in detail. The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present invention and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the invention can be made without departing from the principles of the invention and these modifications and adaptations are intended to be within the scope of the invention as defined in the following claims. The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.