System and method for regenerating waste vulcanized rubber and simultaneously preparing rubber compound

Abstract

The invention discloses a device and a method for regenerating waste vulcanized rubber and simultaneously preparing rubber compound. The system for regenerating the waste vulcanized rubber and simultaneously preparing the rubber compound comprises a feeding and conveying device, a stirring and heating device, an auxiliary mixing and stirring device, a cooling and stirring device and a kneading device. According to the device and the method for regenerating the waste vulcanized rubber and simultaneously preparing the rubber compound, the existing regeneration and mixing process is improved, after the vulcanized rubber powder and the desulfurization auxiliary agent are heated to the preset temperature and preliminarily desulfurized to form the activated rubber powder, the mixing auxiliary agent is added, so that mixing is completed while the activated rubber powder is subjected to subsequent further desulfurization treatment in the prior art; compared with an existing method for preparing the rubber compound after regeneration is completed, the method has the advantages that the cooled and formed reclaimed rubber does not need to be heated again, meanwhile, follow-up mixing equipment and manpower are not needed, and the equipment cost and energy and manpower consumption can be effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of recycling waste vulcanized rubber, and in particular relates to a system and method for simultaneously recycling waste vulcanized rubber and preparing mixed rubber. Background Art

[0002] The recycling of waste rubber refers to the use of physical or chemical methods to destroy the cross-linked network structure of rubber and restore it to a linear state, that is, the sulfur-sulfur (S-S) bond is reopened, so that the waste rubber has a certain plasticity and viscosity and can be reprocessed and used. Recycled rubber can partially replace raw rubber for rubber products, which can save raw rubber and carbon black and is also beneficial to improve processing performance and certain properties of rubber products. The recycling process is the process in which waste rubber breaks some molecular chains and cross-linking points of vulcanized rubber under the combined action of plasticizers, oxygen, heat and machinery.

[0003] Recycled rubber has low cost and good processability. With the improvement of waste rubber recycling technology, the application field of recycled rubber has been further expanded. It is widely used in rubber products such as automobile tires, bicycle tires, hoses and tapes, waterproof rolls, pads, soles, etc.

[0004] In the prior art, during the use of reclaimed rubber, depending on the final product, it is necessary to mix the reclaimed rubber with chemical additives of different formulations (carbon black, light calcium carbonate, zinc oxide, stearic acid, paraffin, antioxidant, etc.) in a mixing device such as an open mixer or an internal mixer to complete the preparation of a mixed rubber. However, in the existing solution, mixing requires reheating the reclaimed rubber that has been cooled into a flake to the mixing temperature, and requires manpower and equipment to add the reclaimed rubber and chemical additives in a certain order for mixing. Summary of the invention

[0005] In view of the above problems, the present invention discloses a system and method for directly preparing a rubber compound by regenerating waste vulcanized rubber in the process of waste rubber regeneration, so as to reduce equipment cost, energy and manpower consumption.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: on the one hand, the present invention provides a system for regenerating waste vulcanized rubber and preparing mixed rubber at the same time, the system comprising: a feeding and conveying device, a stirring and heating device, an auxiliary agent mixing and stirring device, a cooling and stirring device and a kneading device; wherein the feeding and conveying device comprises a desulfurization feeding and conveying device and a mixing and conveying feeding and conveying device, the desulfurization feeding and conveying device cooperates with the stirring and heating device to convey the vulcanized rubber powder particles and the desulfurization auxiliary agent to the stirring and heating device; the mixing and conveying device cooperates with the auxiliary agent mixing and stirring device to convey the mixing auxiliary agent to the auxiliary agent mixing and stirring device; the stirring and heating device comprises a stirring bin and a stirring shaft arranged in the stirring bin, which is used to convey the desulfurization feeding and conveying device to the mixing and conveying device; The vulcanized rubber powder particles and the desulfurization auxiliary agent are stirred and rubbed to heat up to a preset temperature, and activated rubber powder is formed and then discharged into the auxiliary agent mixing and stirring device; the auxiliary agent mixing and stirring device includes a shell and a mixing shaft arranged in the shell, which is used to mix the mixing auxiliary agent and the activated rubber powder evenly to form activated rubber powder of mixed rubber and then discharge it into the cooling and stirring device; the cooling and stirring device is used to cool and stir the activated rubber powder of mixed rubber and transport the activated rubber powder of mixed rubber to the kneading device; the kneading device includes an outer shell and a rotating main shaft arranged in the outer shell, a plurality of disc knives are arranged on the rotating main shaft, and a fixed knife arranged crosswise with the disc knife is arranged on the outer shell, and the shear force generated between the fixed knife and the disc knife is used to further de-crosslink and mix the activated rubber powder of the mixed rubber after cooling and stirring.

[0007] Optionally, the system further comprises a refining device, which is arranged downstream of the kneading device, and comprises cooling rollers with different speed ratios, for refining and shaping the rubber powder discharged from the kneading device.

[0008] Optionally, the system further comprises a screw conveyor, the screw conveyor comprises a cooling water jacket, and cooling circulating water is passed into the cooling water jacket for cooling the conveyed rubber powder.

[0009] Optionally, the auxiliary agent mixing and stirring device includes a shell and a mixing shaft arranged in the shell, the mixing shaft includes a shaft body and stirring blades arranged on the shaft body, the stirring blades include a first stirring blade and a second stirring blade, the first stirring blade extends from the first end of the shaft body to the middle, the second stirring blade extends from the second end of the shaft body to the middle, and the stirring and pushing directions of the first stirring blade and the second stirring blade are opposite.

[0010] Optionally, a pressure relief hole is provided on the shell of the auxiliary agent mixing and stirring device;

[0011] Optionally, the desulfurization feed conveying device includes a conveying device and a weighing device cooperating with the conveying device.

[0012] Optionally, the conveying device includes a spiral rubber powder conveying device and an adding scale cooperating with the spiral rubber powder conveying device; and / or the conveying device includes a conveying pump and a subtracting scale cooperating with the conveying pump.

[0013] Optionally, an exhaust valve is provided on the stirring bin, and the exhaust valve is opened when the desulfurization feed conveying device is loaded, and is closed when the desulfurization feed conveying device stops loading.

[0014] Optionally, the mixing and feeding conveying device includes a weighing silo, a weighing device cooperating with the weighing silo, and at least one feeding device cooperating with the weighing silo; the discharge port of the weighing silo is connected to the auxiliary agent mixing and stirring device.

[0015] Optionally, a spiral feeding disc corresponding to the position of the feed inlet is provided at the front end of the rotating main shaft of the kneading device.

[0016] Another aspect of the present invention provides a method for regenerating waste vulcanized rubber and preparing a rubber mix at the same time, the method comprising the following steps: heating the vulcanized rubber powder and the desulfurization aid to a preset temperature by stirring and friction according to a preset ratio to obtain activated rubber powder; adding a preset weight of the mixing aid to the activated rubber powder and stirring evenly to form an activated rubber mix; cooling and stirring the activated rubber mix; and further de-crosslinking and mixing the cooled and stirred activated rubber mix by mechanical shear force, thereby achieving activation, regeneration and mixing of the vulcanized rubber powder.

[0017] Optionally, the method further comprises: refining and shaping the activated, regenerated and mixed rubber powder.

[0018] Optionally, the method further comprises: while heating the vulcanized rubber powder and the desulfurization aid to a preset temperature by stirring and friction according to a preset ratio to obtain the activated rubber powder, the mixing aid is weighed and prepared according to a preset weight.

[0019] Optionally, the method further comprises: stirring the activated rubber powder added with the mixing aid from both sides toward the middle by means of symmetrically arranged spiral stirring devices to stir evenly.

[0020] According to the device and method for regenerating waste vulcanized rubber and preparing mixed rubber at the same time, the existing regeneration and mixing process (i.e., mixing after regeneration is completed) is improved. After the vulcanized rubber powder and the desulfurization aid are heated to a preset temperature for preliminary desulfurization to form activated rubber powder, the mixing aid is added, so that the mixing is completed while the existing subsequent desulfurization treatment of the activated rubber powder is utilized to directly prepare the mixed rubber. Compared with the existing mixing after regeneration, it is no longer necessary to heat the cooled and formed regenerated rubber again, and no subsequent mixing equipment and manpower are required, which can effectively reduce equipment costs, energy and manpower consumption.

[0021] In addition, the present invention adopts a stirring friction heating method. Compared with the electric heating process in the prior art, on the one hand, it can eliminate the electric heating equipment and reduce the equipment cost; on the other hand, it adopts the method of mechanical energy shear friction heat generation, which can improve the overall energy conversion efficiency and effectively reduce the energy consumption of the entire equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0023] Figure 1 This is a schematic structural diagram of a system for regenerating waste vulcanized rubber and preparing a rubber compound at the same time according to the present invention;

[0024] Figure 2 This is a schematic structural diagram of an auxiliary agent mixing and stirring device of a system for simultaneously preparing a rubber compound from recycled waste vulcanized rubber according to the present invention;

[0025] Figure 3 This is a schematic diagram of the structure of a refining device of the system for regenerating waste vulcanized rubber and preparing mixed rubber at the same time according to the present invention; DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In order to overcome the problems of high cost of equipment for preparing rubber mix, large energy and manpower consumption in the prior art, the present invention proposes a new system for regenerating waste vulcanized rubber and preparing rubber mix at the same time. In the process of regenerating waste vulcanized rubber, rubber mix is ​​directly prepared, which simplifies the equipment and process and can significantly reduce the equipment cost and use cost. The technical solutions provided by various embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0028] First embodiment:

[0029] like Figure 1As shown, the first embodiment of the present invention provides a system for regenerating waste vulcanized rubber and preparing mixed rubber at the same time, the system comprising: a feed conveying device 10, a stirring and heating device 20, an auxiliary agent mixing and stirring device 30, a cooling and stirring device 40 and a kneading device 50; wherein the feed conveying device 10 comprises a desulfurization feed conveying device 11 and a mixing feed conveying device 12, the desulfurization feed conveying device 11 cooperates with the stirring and heating device 20 to convey vulcanized rubber powder particles and desulfurization auxiliary agent to the stirring and heating device 20; the mixing feed conveying device 12 cooperates with the auxiliary agent mixing and stirring device 30 to convey the mixing auxiliary agent to the auxiliary agent mixing and stirring device 30; the stirring and heating device 20 comprises a stirring bin and a stirring shaft arranged in the stirring bin, which is used to convey the desulfurization feed conveying device 11 to the mixing auxiliary agent; The vulcanized rubber powder particles and the desulfurization auxiliary agent transported by 11 are stirred and rubbed to heat up to a preset temperature, and activated rubber powder is formed and then discharged into the auxiliary agent mixing and stirring device 30; the auxiliary agent mixing and stirring device 30 includes a shell and a mixing shaft arranged in the shell, which is used to mix the mixing auxiliary agent and the activated rubber powder evenly to form activated rubber powder of mixed rubber and then discharge it into the cooling and stirring device 40; the cooling and stirring device 40 is used to cool and stir the activated rubber powder of mixed rubber and transport the activated rubber powder of mixed rubber to the kneading device 50; the kneading device 50 includes an outer shell and a rotating main shaft arranged in the outer shell, a plurality of disc knives are arranged on the rotating main shaft, and a fixed knife arranged crosswise with the disc knife is arranged on the outer shell, and the shear force generated between the fixed knife and the disc knife is used to further de-crosslink and mix the activated rubber powder of the mixed rubber after cooling and stirring.

[0030] That is, the system for regenerating waste vulcanized rubber and preparing mixed rubber at the same time of the present invention improves the existing regeneration and mixing process (i.e., mixing after regeneration is completed in the current technology). After the vulcanized rubber powder and the softener are heated to a preset temperature for preliminary desulfurization to form activated rubber powder, a mixing aid is added through the auxiliary agent mixing and stirring device 30, so that the mixing is completed at the same time by utilizing the existing equipment for further desulfurization of the activated rubber powder, and the mixed rubber is directly prepared. Compared with the existing mixing after regeneration, it is no longer necessary to heat the cooled and formed regenerated rubber again, and no subsequent mixing equipment and manpower are required, which can effectively reduce equipment costs, energy and manpower consumption.

[0031] Preferably, the system for regenerating waste vulcanized rubber and preparing mixed rubber of the present invention also includes a control device, which controls the actions of each device as a whole, so as to complete various actions such as feeding, stirring, heating and activation, adding mixing aids, stirring evenly, cooling, kneading, etc. More preferably, the control device adopts a DCS distributed control system to centrally monitor, operate, manage and decentralized control the production process. The DCS system usually adopts the international standard protocol TCP / IP, which is a dual-redundant high-speed communication network. The system has better expansibility and openness, stronger security, and more flexible programming and control.

[0032] The feeding conveying device 10 also includes a conveying device and a weighing device matched with the conveying device, so as to achieve accurate weighing of the vulcanized rubber powder and various additives. Specifically, according to the performance characteristics of the vulcanized rubber powder and different additives, the conveying device and the weighing device adopt different methods.

[0033] Specifically, the vulcanized rubber powder can be transported by a screw conveying device, and the weight of the rubber powder can be measured by an addition scale, which cooperates with the control device. When the vulcanized rubber powder reaches a preset weight, the screw conveying device stops, thereby completing the weighing of the vulcanized rubber powder and conveying it to the stirring and heating device 20; the desulfurization aid is weighed by a gear pump in combination with a weighing subtraction scale, which cooperates with the control device. When the pumping volume reaches a preset weight, the gear pump stops to achieve automatic control.

[0034] After the desulfurization feeding and conveying device 11 completes the feeding of the vulcanized rubber powder and the desulfurization aid to the stirring bin of the stirring and heating device 20, the motor is started to drive the stirring shaft in the stirring bin to rotate at a high speed, and the blades arranged on the stirring shaft push, lift and shear the vulcanized rubber powder and the desulfurization aid, so that the rubber powder and the desulfurization aid are evenly mixed and collide, shear and rub at high speed, so that the rubber powder is quickly heated to the desulfurization temperature, and the rubber powder is physically regenerated to produce a heat-raising reaction. Thereby, part of the sulfur-containing chemical bonds of the large network cross-linked structure in the rubber powder are interrupted, thereby forming a plurality of small network structures of activated rubber powder, completing the preliminary desulfurization of the vulcanized rubber powder, forming activated rubber powder, and when the temperature of the rubber powder reaches the preset regeneration temperature requirement, the control device will quickly open the discharge valve and unload the material within a preset time (such as 30 seconds). The present invention adopts a stirring friction heating method. Compared with the process method of using electric heating in the prior art, on the one hand, the electric heating equipment can be removed, and the equipment cost can be reduced; on the other hand, the method of using mechanical energy shearing friction heat generation can improve the overall energy conversion efficiency and effectively reduce the energy consumption of the entire equipment.

[0035] In addition, as needed, an air outlet can be set above the mixing bin, which will automatically overflow when there is pressure and directly connect to environmental protection equipment (electrically heated organic waste gas thermal oxidation device, etc.). An exhaust valve can also be set on the mixing bin. By cooperating with the control device, the exhaust valve opens when the desulfurization feed conveying device 11 is feeding, and closes when the desulfurization feed conveying device 11 stops feeding. By setting the exhaust valve, the air pressure in the mixing bin can be balanced, which is convenient for quick feeding. In addition, the exhaust valve is connected to the corresponding environmental protection device to treat the exhaust gas and prevent the exhaust gas from polluting the environment.

[0036] After or while the activated rubber powder in the stirring bin of the stirring and heating device 20 is quickly placed into the housing (mixing and stirring bin) of the additive mixing and stirring device 30, the mixing aid is also quickly input into the mixing and stirring bin through the mixing and feeding conveying device 12, and the activated rubber powder and the mixing aid are quickly and evenly mixed through the stirring action of the mixing shaft. Similarly, a pressure relief hole is provided on the housing of the additive mixing and stirring device 30, so as to facilitate the balance of air pressure when the activated rubber powder and the mixing aid are added. Similarly, the pressure relief hole is also connected to a corresponding environmental protection device to achieve waste gas treatment and prevent waste gas from polluting the environment.

[0037] Preferably, in order to facilitate uniform stirring, the mixing shaft includes a shaft body and stirring blades arranged on the shaft body, the stirring blades include a first stirring blade and a second stirring blade, the first stirring blade extends from the first end of the shaft body to the middle, and the second stirring blade extends from the second end of the shaft body to the middle, and the stirring and pushing directions of the first stirring blade and the second stirring blade are opposite, that is, the first stirring blade and the second stirring blade are symmetrically arranged, so that the materials are mixed from both ends to the middle, so that the activated rubber powder and the mixing aid are quickly and evenly mixed.

[0038] In addition, since there are relatively many components of mixing aids (such as: raw rubber particles, zinc oxide, stearic acid, paraffin, antioxidant, carbon black, and some fillers, it should be noted that the present invention does not involve specific improvements in mixing aids. According to the final use of the mixed rubber, the selection of mixing aid formulas can refer to the existing technology), in order to facilitate the weighing of multiple additives, a weighing silo, a weighing device matched with the weighing silo, and at least one feeding device matched with the weighing silo can be provided; generally, the weighing silo is arranged above the additive mixing device 30, the feeding device adopts a screw conveying device, the weighing device adopts an addition scale, and the control device uses an addition scale to measure the weight of different materials. Specifically, when the first additive reaches the preset weight, the screw conveyor stops; the screw conveyor of the second additive is automatically started, and when the second additive reaches the preset weight, the screw conveyor stops; the screw conveyor of the third additive is automatically started, and when the third additive reaches the preset weight, the screw conveyor stops. By analogy, multiple additives and materials can be automatically measured. The discharge port of the weighing silo is connected to the additive mixing and stirring device 30. After the initial desulfurization forms activated rubber powder and is discharged into the additive mixing and stirring device 30 through the stirring and heating device 20, all the prepared materials in the weighing silo are added to the additive mixing and stirring device 30. After the transportation is completed, the weighing silo starts the next round of weighing and metering of multiple additives. According to needs, the weighing silo can be matched with the corresponding discharge valve and screw conveying device, and automatically controlled by the control system.

[0039] The discharge port of the mixing and stirring bin is connected to the cooling and stirring device 40. According to the discharging situation, when the stirring and heating device 20 still has a preset time (for example, 1 minute) to discharge, the pneumatic knife gate valve arranged under the mixing and stirring bin will automatically open and put the mixed material into the cooling and stirring device 40. After the material in the mixing and stirring bin is emptied, the pneumatic knife gate will automatically close, waiting for the stirring and heating device 20 to discharge the material into the mixing bin of the mixing machine.

[0040] The cooling and stirring device 40 includes a cooling and stirring box and a cooling jacket arranged outside the box. The materials placed in the mixing and stirring chamber continue to be cooled and stirred in the cooling and stirring box. The cooling jacket is filled with circulating cooling water, which uses heat conduction to quickly take away the heat of the rubber powder to achieve the purpose of cooling the rubber powder. There is a main shaft in the middle of the cooling and stirring box, and the main shaft has blades. The main shaft is rotated to quickly stir the materials to achieve the purpose of uniform stirring and rapid cooling. There is a screw conveyor at the bottom of the cooling and stirring box. By adjusting the speed, the material conveying amount is adjusted, and it is used to convey the evenly stirred materials to the kneading device 50.

[0041] The kneading device 50 adopts a knife-type rotary push, that is, the kneading device 50 includes a shell and a rotating main shaft arranged in the shell, a plurality of disc knives are arranged on the rotating main shaft, and a fixed knife arranged crosswise with the disc knives is arranged on the shell, and the activated rubber powder of the mixed rubber passes through the gap between the disc knives and the fixed knife. The shear force generated between the fixed knife and the disc knife is used to strongly knead and shear the activated rubber powder of the mixed rubber, and the small mesh rubber particles in the mixed rubber powder are forcibly separated in situ, thereby achieving further de-crosslinking and mixing of the activated rubber powder of the mixed rubber after cooling and stirring. Preferably, the front end of the rotating main shaft of the kneading device 50 is provided with a spiral feeding disk corresponding to the position of the feed port, so as to play a role of forced feeding, increase the distributed mixing effect and shearing effect of the mixed rubber powder, and improve the production of the mixed rubber. More preferably, the spiral feeding disk adopts a double-headed spiral feeding disk to further increase the extrusion force.

[0042] The kneading device 50 also includes a cooling water jacket, preferably a barrel that is fully submerged in a cooling water tank, which can quickly remove the heat generated by mechanical and rubber friction, and achieve low-temperature strong shearing and environmental protection. The effect of reducing Mooney can also be adjusted by adjusting the amount of cooling water. A water nozzle is set at the feed port of the kneading device 50, and a pulse pump is used to supply water to ensure the softness and fluidity of the mixed rubber and the stability of various indicators such as the tensile strength, elongation at break, and Mooney viscosity of the rubber.

[0043] Preferably, the system for regenerating waste vulcanized rubber and preparing mixed rubber also includes a refining device 70, which includes cooling rollers with different speed ratios, and is used to refine and shape the rubber powder discharged from the kneading device 50. Specifically, the refiner adopts a 810*710*1530 cooling roller, and is controlled by a dual motor and dual reducer frequency conversion. The speed ratio of the refiner can be adjusted arbitrarily, and there is no noise from the speed ratio gear. The mixed rubber material is sheared with a 10-wire thin pass strength on the refiner, and after being refined again on the second refiner, it is transported to the rubber extruder for molding, air cooling, weighing, cutting, and stacking.

[0044] More preferably, the refining device 70 is also used in conjunction with a screw conveyor 60, which includes a cooling water jacket, and cooling circulating water is passed into the cooling water jacket to cool the conveyed rubber powder. The feed end of the screw conveyor cooperates with the kneading device 50, and the discharge end cooperates with the feed end of the refining device 70. That is, the mixed rubber mixed and sheared by the kneading device 50 is squeezed out from the discharge flower plate hole and basically forms a small ball. The screw conveyor cools it down again and transports it to the rubber refining device 70, further reducing the temperature of the mixed rubber, which plays a more environmentally friendly role.

[0045] Second embodiment:

[0046] The present invention also provides a method for regenerating waste vulcanized rubber and preparing a rubber compound, the method comprising the following steps:

[0047] The vulcanized rubber powder and the desulfurization aid are heated to a preset temperature by stirring and friction according to a preset ratio to obtain activated rubber powder; a preset weight of mixing aid is added to the activated rubber powder and stirred evenly to form a mixed rubber activated rubber powder; the mixed rubber activated rubber powder is cooled and stirred; the cooled and stirred mixed rubber activated rubber powder is further de-crosslinked and mixed by mechanical shear force, thereby realizing the activation, regeneration and mixing of the vulcanized rubber powder.

[0048] That is, the method for regenerating waste vulcanized rubber and preparing mixed rubber at the same time of the present invention improves the existing regeneration and mixing process (i.e., mixing after regeneration is completed). After the vulcanized rubber powder and the desulfurization aid are heated to a preset temperature for preliminary desulfurization to form activated rubber powder, the mixing aid is added, thereby utilizing the existing subsequent desulfurization treatment of the activated rubber powder while completing the mixing, and directly preparing the mixed rubber. Compared with the existing mixing after regeneration is completed, it is no longer necessary to heat the cooled and formed regenerated rubber again, and it is also no longer necessary to have subsequent mixing equipment and manpower, which can effectively reduce equipment costs, energy and manpower consumption.

[0049] In addition, the present invention adopts a stirring friction heating method. Compared with the electric heating process in the prior art, on the one hand, it can eliminate the electric heating equipment and reduce the equipment cost; on the other hand, it adopts the method of mechanical energy shear friction heat generation, which can improve the overall energy conversion efficiency and effectively reduce the energy consumption of the entire equipment.

[0050] Preferably, the method also includes: refining and forming the activated, regenerated and mixed rubber powder to remove impurities and improve quality, and forming and stacking are achieved through an extruder, an air cooler, a weighing and cutting machine, and a stacking machine to facilitate subsequent processing.

[0051] More preferably, the method further comprises, since there are relatively more mixing aid components (such as: raw rubber particles, zinc oxide, stearic acid, paraffin, antioxidant, carbon black, part of the filler, it should be noted that the present invention does not involve specific mixing aid improvements, and the selection of mixing aid formulas can refer to the prior art according to the final use of the mixed rubber), in order to improve efficiency, the vulcanized rubber powder and the desulfurization aid are heated to a preset temperature by stirring friction according to a preset ratio, and the mixing aid is weighed and prepared according to a preset weight while obtaining the activated rubber powder, so that the mixing aid can be added to the activated rubber powder immediately after the friction heating is completed. In addition, in order to improve the mixing efficiency, the activated rubber powder added with the mixing aid is stirred from both sides to the middle by a symmetrically arranged spiral stirring device, so that the activated rubber powder and the mixing aid are quickly stirred and uniformly.

[0052] Third embodiment:

[0053] The system and method for regenerating waste vulcanized rubber and preparing mixed rubber in the first and second embodiments above are used to make a mixed rubber of a pad belt product using 12Mpa recycled rubber as an experimental sample for analysis:

[0054] Table 1. Compounding aid formula

[0055] Zinc Oxide 2.5 Stearic acid 1 paraffin 0.5 Antioxidant 4010NA 0.75 Carbon Black N220 3 Light calcium carbonate 10

[0056] The six mixing aids in Table 1 are added to the stirring and heating device 20 for preliminary desulfurization to form activated rubber powder, and then extruded through the additive mixing and stirring device 30, the cooling and stirring device 40, the kneading device 50 and the refining device 70 to directly prepare a mixed rubber;

[0057] Before preparing the pad with the above-mentioned first-stage mixed rubber, accelerator and sulfur are added on an internal mixer or an open mixer according to the following Table 2 to prepare vulcanized rubber. The performance indicators of the obtained vulcanized rubber are shown in Table 3.

[0058] Table 2. Vulcanization formula

[0059] One-stage compound rubber 120 Accelerator Ns 0.96 sulfur 1.5

[0060] Table 3. Properties of vulcanized rubber at 145℃X3:30

[0061] project index result Tensile strengthMpa ≥10.0 11.18 Elongation at break % ≥380 450 Tear strength KN / m ≥40 48.3 Compression set % ≤30 28 Hardness Shore A 60±4 64

[0062] Referring to Table 3 above, the vulcanized rubber produced by the system and method of the present invention can meet the performance index requirements, and compared with the prior art, which usually uses a 150L internal mixer (one-stage mixing) as an example, with a power of 250KW, and puts it into an open mixer (two-stage mixing) after internal mixing, with a power of 75KW, the system and method of the present invention can save about 300 degrees of electricity per ton of mixed rubber, save 2 people, and effectively reduce the cost of use.

[0063] In summary, the system and method for regenerating waste vulcanized rubber and preparing mixed rubber at the same time of the present invention improves the existing regeneration and mixing process (i.e., mixing after regeneration is completed). After the vulcanized rubber powder and the softener are heated to a preset temperature for preliminary desulfurization to form activated rubber powder, a mixing aid is added, thereby utilizing the existing subsequent further desulfurization treatment of the activated rubber powder while completing mixing, and directly preparing mixed rubber. Compared with the existing mixing after regeneration is completed, it is no longer necessary to heat the cooled and formed regenerated rubber again, and it is no longer necessary to have subsequent mixing equipment and manpower, which can effectively reduce equipment costs, energy and manpower consumption. In addition, the present invention adopts a stirring friction heating method, which can remove the electric heating equipment and reduce equipment costs compared to the electric heating process in the prior art; on the other hand, the mechanical energy shear friction heat generation method can improve the overall energy conversion efficiency and effectively reduce the energy consumption of the entire equipment.

[0064] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A system for regenerating waste vulcanized rubber and preparing mixed rubber, characterized in that: The system comprises: a feeding and conveying device (10), a stirring and heating device (20), an auxiliary agent mixing and stirring device (30), a cooling and stirring device (40) and a kneading device (50); The feed conveying device (10) comprises a desulfurization feed conveying device (11) and a mixing feed conveying device (12); the desulfurization feed conveying device (11) cooperates with a stirring and heating device (20) to convey vulcanized rubber powder particles and a desulfurization auxiliary agent to the stirring and heating device (20); the mixing feed conveying device (12) cooperates with an auxiliary agent mixing and stirring device (30) to convey the mixing auxiliary agent to the auxiliary agent mixing and stirring device (30); The stirring and heating device (20) comprises a stirring bin and a stirring shaft arranged in the stirring bin, and is used to stir and frictionally heat the vulcanized rubber powder particles and the desulfurization auxiliary agent conveyed by the desulfurization feeding conveying device (11) to a preset temperature, and then discharge the activated rubber powder into the auxiliary agent mixing and stirring device (30); The auxiliary agent mixing and stirring device (30) comprises a shell and a mixing shaft arranged in the shell, and is used to evenly mix the mixing auxiliary agent with the activated rubber powder to form a mixed rubber activated rubber powder, and then discharge it into the cooling and stirring device (40); The cooling and stirring device (40) is used to cool and stir the activated rubber powder of the mixed rubber and transport the activated rubber powder of the mixed rubber to the kneading device (50); The kneading device (50) comprises an outer shell and a rotating main shaft arranged in the outer shell, a plurality of disc knives are arranged on the rotating main shaft, and a fixed knife arranged crosswise with the disc knives is arranged on the outer shell. The shear force generated between the fixed knife and the disc knives is used to further de-crosslink and mix the activated rubber powder of the mixed rubber after cooling and stirring.

2. The system according to claim 1, characterized in that The system further comprises a refining device (70), which is arranged downstream of the refining device (50). The refining device (70) comprises cooling rollers with different speed ratios and is used for refining and shaping the rubber powder discharged from the refining device (50).

3. The system according to claim 2, characterized in that The system further comprises a screw conveyor (60), wherein the screw conveyor (60) comprises a cooling water jacket, and cooling circulating water is passed into the cooling water jacket for cooling the conveyed rubber powder.

4. The system according to claim 1, characterized in that The auxiliary agent mixing and stirring device (30) comprises a shell and a mixing shaft arranged in the shell, the mixing shaft comprises a shaft body and stirring blades arranged on the shaft body, the stirring blades comprise a first stirring blade and a second stirring blade, the first stirring blade extends from the first end of the shaft body to the middle, the second stirring blade extends from the second end of the shaft body to the middle, and the stirring and pushing directions of the first stirring blade and the second stirring blade are opposite.

5. The system according to claim 1, characterized in that A pressure relief hole is provided on the shell of the auxiliary agent mixing and stirring device (30).

6. The system according to claim 1, characterized in that The desulfurization feed conveying device (11) comprises a conveying device and a weighing device coordinated with the conveying device.

7. The system according to claim 6, characterized in that The conveying device comprises a spiral rubber powder conveying device and an adding scale matched with the spiral rubber powder conveying device; and / or the conveying device comprises a conveying pump and a subtracting scale matched with the conveying pump.

8. The system according to claim 1, characterized in that An exhaust valve is arranged on the stirring bin, and the exhaust valve is opened when the desulfurization feed conveying device (11) is loaded with materials, and is closed when the desulfurization feed conveying device (11) stops loading materials.

9. The system according to claim 1, characterized in that The mixing and feeding conveying device (12) comprises a weighing bin, a weighing device matched with the weighing bin, and at least one feeding device matched with the weighing bin; The discharge port of the weighing silo is connected to the auxiliary agent mixing and stirring device (30).

10. The system according to claim 1, characterized in that The front end of the rotating main shaft of the kneading device (50) is provided with a spiral feeding disk corresponding to the position of the feed inlet.

11. A method for regenerating waste vulcanized rubber and preparing a rubber compound, characterized in that: The method comprises the following steps: The vulcanized rubber powder and the desulfurization aid are heated to a preset temperature by stirring and friction according to a preset ratio to obtain activated rubber powder; Adding a preset weight of a mixing aid to the activated rubber powder and stirring evenly to form a mixed rubber activated rubber powder; Cooling and stirring the rubber mixture to activate the rubber powder; The mechanical shear force is used to further de-crosslink and mix the activated rubber powder of the mixed rubber after cooling and stirring, so as to realize the activation, regeneration and mixing of the vulcanized rubber powder.

12. The method according to claim 11, characterized in that The method further comprises: subjecting the activated, regenerated and mixed rubber powder to a refining and forming process.

13. The method according to claim 11, characterized in that The method further comprises: The vulcanized rubber powder and the desulfurization auxiliary agent are heated to a preset temperature by stirring and friction according to a preset ratio to obtain the activated rubber powder, and at the same time, the mixing auxiliary agent is weighed and prepared according to a preset weight.

14. The method according to claim 11, characterized in that The method further comprises: The activated rubber powder added with the mixing aid is stirred from both sides to the middle by a symmetrically arranged spiral stirring device to be evenly stirred.

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