Industrial continuous silicone rubber degradation process

Abstract

The invention relates to the field of environmental protection, more relates to the field of comprehensive utilization of waste silicone rubber, and particularly provides an industrial continuous silicone rubber degradation process, which comprises the following steps: carrying out pre-reaction on waste silicone rubber and a catalyst by utilizing a plurality of groups of stirring reactors, introducing reactants into a continuous degradation device after completing the pre-reaction in the stirring reactors, and continuously degrading the reactants in the continuous degradation device; quickly dispersing and heating the reactants by using a solid heat carrier, so that the reactants are quickly cracked in the continuous degradation device; the pre-reaction can promote better mixing of the catalyst and the waste silicone rubber and partial degradation, so that the mobility of the mixed material is better, and the mixed material can be better dispersed and cracked after entering the continuous degradation device; the continuous degradation of the waste silicone rubber is realized, the problem of discontinuous cracking in the prior art is solved, the problem of insufficient cracking caused by reduction of heat-conducting property due to material viscosity in the prior art is avoided, and meanwhile, the service life of equipment is greatly prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of environmental protection, and more particularly to the field of comprehensive utilization of waste silicone rubber, and specifically provides an industrial continuous silicone rubber degradation process. BACKGROUND

[0002] Silicone rubber is a synthetic rubber with a main chain of siloxane bonds, which has excellent heat resistance, cold resistance, dielectricity, ozone resistance and aging resistance, and is widely used in aerospace, electronics, light industry, chemical industry and other fields. With the increasing demand for silicone rubber products in the existing market, the amount of waste silicone rubber during the production process of silicone rubber, as well as after use, is rapidly increasing. The waste and corner materials can be recycled, but a large amount of waste silicone rubber, if not recycled, not only occupies space, but also wastes resources and pollutes the environment.

[0003] At present, the main method for recycling waste silicone rubber and corner waste is to crack linear dimethylsiloxane in waste silicone rubber into dimethylcyclosiloxane mixture (DMC) through a recycling system, and continuously remove it from the reaction system. After purification treatment, high-purity dimethylcyclosiloxane mixture (DMC) can be obtained, and it can be used as raw material for the production of silicone oil, silicone rubber and silicone resin. The existing main application is still acid catalytic cracking method and base catalytic cracking method, and these two cracking methods have their own shortcomings. Among them, KOH is the most commonly used base catalyst, which has a large amount of catalyst during use, which may cause safety accidents due to excessive local reaction, and the application field of base catalytic method is small and difficult to better promote and apply. The acid catalytic cracking method mainly uses acid as a catalyst, which has the advantages of mild reaction and relatively safe conditions, but the large amount of use of acid catalyst causes serious corrosion of the equipment, which needs to be replaced regularly, resulting in high production cost. The existing acid catalytic cracking method generally uses a single reaction kettle to add silicone rubber and catalyst at the same time. This method can only be processed intermittently, and because DMC is continuously produced and discharged from the system during the degradation process, the molecular weight of the remaining silicone rubber gradually increases and becomes viscous, which leads to poor stirring performance and heat conduction performance, reduces the cracking efficiency, greatly increases the cracking temperature and time, and the increasingly viscous reactants bring greater resistance to the stirring kettle, causing difficulty in discharging the reaction kettle and more easily causing damage to the equipment.

[0004] Therefore, it is urgent to develop a process method for continuous treatment of waste silicone rubber to better realize the resource treatment of waste silicone rubber and corner materials. SUMMARY

[0005] In view of the problems existing in the treatment of waste silicone rubber, the present application provides an industrial continuous silicone rubber degradation process. The process pre-reacts waste silicone rubber and catalyst in multiple groups of stirring reactors, and then introduces the reaction mixture into a continuous degradation device. The reaction mixture is rapidly dispersed and heated by solid heat carriers, so that the reaction mixture is rapidly cracked in the continuous degradation device. The pre-reaction can promote better mixing of the catalyst and waste silicone rubber, and partial degradation occurs, so that the fluidity of the mixture is better, and the mixture can be better dispersed and cracked after entering the continuous degradation device. The stirring reactor is provided with multiple groups, and each group is sealingly connected with the continuous degradation device. In this way, the occurrence sequence of the pre-reaction can be controlled to realize continuous feeding of the continuous degradation device, thereby realizing continuous degradation of waste silicone rubber, changing the intermittent cracking problem of the prior art, avoiding the problem of insufficient cracking caused by the decrease in thermal conductivity due to the viscosity of the material in the prior art, and greatly prolonging the service life of the equipment.

[0006] The main idea of the present application is to divide the degradation of waste silicone rubber into pre-reaction and continuous degradation. The pre-reaction is completed in the stirring reactor. Under the action of stirring, the waste silicone rubber and the catalyst are uniformly mixed and a small amount of dimethylcyclosiloxane mixture (DMC) is produced. This part of dimethylcyclosiloxane mixture is discharged from the stirring reactor. At the same time, the mixture in the reactor is degraded, and its fluidity is better and can be better heated. After the pre-reaction for a specified time, the mixture is sealingly introduced into the continuous degradation device. The device is provided with a large number of solid heat carriers. The mixture adheres to the surface of the solid heat carriers after contact to form a thin layer, and the heating effect is obviously improved. Rapid degradation can be achieved at a lower temperature to release more dimethylcyclosiloxane mixture (DMC). The undegraded substances collide with each other during the movement of the solid heat carriers and separate from the solid heat carriers. Finally, the degradation of waste silicone rubber is completed by sealing the discharge of the discharge mechanism at the tail of the continuous degradation device. Under the guidance of the above inventive concept, the specific technical solutions of the present application are as follows: An industrial continuous silicone rubber degradation process, the specific steps are as follows: The waste silicone rubber of various sources is collected, washed, dehydrated, and then put into a raw material temporary storage bin, and then sent to a transition material bin for further mixing and sent to a metering device. The metered material is sent to a stirring reactor through a sealed feeding machine for pre-reaction. The pre-reacted material is sent to a continuous degradation device through a second sealed feeding machine. The continuous degradation device is preloaded with a solid heat carrier. The pre-reacted material contacts the solid heat carrier and continuously moves from the feeding end to the discharging end of the continuous degradation device to complete the degradation of the material. The degraded material falls through the friction and collision of the solid heat carrier and is finally sealed and discharged from the discharge port of the continuous degradation device. The dimethylcyclosiloxane mixture produced during the pre-reaction and continuous degradation processes is discharged from the reaction device in gaseous form and then converted into a liquid product through a liquid separation cooling device.

[0007] Preferably, the stirring reactor includes a shell and a stirring device arranged in the shell. The interior of the stirring reactor is a sealed cavity. The top is provided with a raw material inlet and a gas outlet, respectively. The bottom is provided with a discharge port which is sealingly connected with the second sealed feeding machine. The shell is a double-shell structure and is provided with a second heat medium inlet and a second heat medium outlet. The waste silicone rubber and the catalyst are mixed in the stirring reactor with the above structure and pre-react under heating conditions. The pre-reaction temperature is controlled at 120-180℃, and the pre-reaction time is 1-2h.

[0008] The catalyst used is selected from concentrated sulfuric acid or dodecylbenzenesulfonic acid, in addition to which a strong base or a composite catalyst can also be used. The above catalysts are common catalysts for waste silicone rubber, and the inventor will not repeat them. The catalyst dosage is 1-5% of the weight of the waste silicone rubber.

[0009] In the pre-reaction process, the waste silicone rubber starts to undergo a small amount of degradation reaction under the action of the catalyst, and a certain amount of gaseous products is released in the system, which contains dimethylcyclosiloxane mixture and other gaseous products, so it is necessary to discharge these gaseous products from the stirring reactor in time and into the liquid separation and cooling device to be converted into liquid products; in this way, the pre-reaction process can be better promoted, and at the same time, due to the degradation reaction, the solid raw materials are gradually converted into a fluid state, which can better promote the mixing of the waste silicone rubber and the catalyst, and it is more convenient for heat transfer, so the heat transfer efficiency is improved, the heating temperature is reduced, and therefore the pre-reaction temperature only needs to be 120-180℃; the second heat medium inlet and the second heat medium outlet on the double-layer shell are used to transport the heat medium for heating the stirring reactor, and the heat medium is discharged from the continuous degradation device, because the heat medium added to the continuous degradation device has a higher temperature, and after heating the continuous degradation device, it still contains a high amount of heat, which can be used to heat the stirring reactor, so that the heat can be maximized, and the equipment cost is reduced; at the same time, due to the change of the material into a fluid state, the load of the stirring device is greatly reduced, the service life is prolonged, and energy is saved.

[0010] The material after pre-reaction is sent into the continuous degradation device through the second sealing feeder, and immediately after entering the device, the material is in contact with the solid heat carrier and adheres to the surface of the solid heat carrier. Since the solid heat carrier continuously moves from the material feeding end to the discharging end in the continuous degradation device, the material will uniformly adhere to each solid heat carrier to form a thin layer of material. Since the heating medium is arranged outside the continuous degradation device, a high temperature is maintained in the entire continuous degradation device, and the solid heat carrier also carries heat when moving in the continuous degradation device. The thin layer of material on the surface of the solid heat carrier is heated faster and more uniformly, so that the material after pre-reaction starts to degrade as soon as it comes into contact with the solid heat carrier, and the degradation process is accelerated by the movement and collision of the solid heat carriers, thereby releasing more dimethylcyclosiloxane mixture and other gaseous products.

[0011] The inventors further control the temperature in the continuous degradation device to be 180-220℃, and the residence time of the material in the continuous degradation device is controlled to be 0.5-1h. Under the above conditions, the waste silicone rubber of various sources can complete the degradation process. A temperature that is too high has little effect on the degradation efficiency, and increases energy consumption and equipment wear. A temperature that is too low has poor degradation effect, and the material needs to stay in the device for a longer time, which is not conducive to the requirement of continuous processing. The inventors further prefer to control the temperature in the continuous degradation device to be 180-200℃.

[0012] The solid heat carrier is preferably a heat-conducting small ball, which can refer to the related technical solutions in the prior applications CN101074385A or CN108911458A, and the inventors do not repeat them here.

[0013] The continuous degradation device used can refer to the waste rubber or plastic continuous cracking equipment described in the prior application CN101484551A, or other prior applications of the applicant, as long as a shell or outer cylinder through which the heat medium passes is arranged outside the continuous cracking device. The above technical solution is also disclosed in the prior application of the inventor, and the inventor does not make specific limitations. The solid heat carrier can be used in the continuous degradation device in a circulating manner or in an external circulating manner. Both of them can be realized by using the existing technology, and in particular, the screening device for separating the solid heat carrier from the solid product in the prior application of the inventor can be selected. The inventor also does not repeat the description.

[0014] Preferably, a heat medium inlet and a heat medium outlet are further arranged on the continuous cracking device. The heat medium for heating the continuous degradation device can be molten salt or heat conducting oil, as long as it can provide the required heat for the continuous degradation device. Moreover, the heat medium can be more conveniently continuously fed into the double-layer shell of the stirring reactor to provide heat for the pre-reaction. The heat medium discharged from the stirring reactor is heated in the heat medium heating device and then continuously heats the continuous degradation device. The waste flue gas used for heating in the heat medium heating device can be directly used as a heat source for cleaning and dewatering the collected waste silicone rubber from various sources, so as to dry the waste silicone rubber. In this way, the heat is maximally utilized, various waste heat resources are fully reused, and the requirements of energy saving and emission reduction in China are more met.

[0015] In the continuous degradation device, the degradation process is rapidly carried out, and more dimethyl cyclosiloxane mixture and other gaseous products are released. Moreover, the yield of the dimethyl cyclosiloxane mixture and other gaseous products is higher in the front reaction zone of the continuous degradation device. This makes the concentration of the dimethyl cyclosiloxane mixture and other gaseous products in the upper space of the front reaction zone higher. In order to avoid the further cracking or side reaction of the dimethyl cyclosiloxane mixture and other gaseous products due to the long residence time in the continuous degradation device, the inventor finally decides to arrange a gaseous product outlet at the front end of the continuous degradation device. In this way, the dimethyl cyclosiloxane mixture and other gaseous products can be discharged from the continuous degradation device through the outlet and enter the liquid separation and cooling device to be converted into liquid products, like the gaseous products generated in the pre-reaction. In this way, the dimethyl cyclosiloxane mixture generated in the pre-reaction and the continuous degradation process can be better collected and converted. Moreover, the temperature in the pre-reaction and the continuous degradation process is not too high, which avoids the further decomposition of the dimethyl cyclosiloxane mixture, thereby improving the overall yield. The total reaction time of the pre-reaction and the continuous degradation is 1.5-3 h, which also reduces the occurrence of side reactions, improves the processing efficiency, reduces the load of the equipment, and prolongs the service life of the equipment.

[0016] Preferably, in order to enable the pre-reaction and continuous degradation process to be continuously carried out, the inventors decide to set a plurality of stirred reactors, the number of which is not less than 2, which are arranged in parallel between each stirred reactor, and are all sealedly connected with the second sealing feeder through a separate discharge channel.

[0017] In this way, the waste silicone rubber can be batched and fed to the stirred reactors in batches, and the material can be discharged in time, so that continuous feeding in the continuous degradation device is ensured, and the treatment effect can be maximized. Of course, when the amount of waste silicone rubber to be treated is small, the continuous degradation device can also be operated in an idle state, so that the problem of shortening the service life of the continuous degradation device caused by interval treatment is avoided.

[0018] Preferably, a nitrogen inlet is further arranged at the discharge end of the continuous degradation device and is connected with a nitrogen storage tank; since the dimethylcyclosiloxane mixture generated in the continuous degradation process is concentrated at the front end of the continuous degradation device, and the gaseous product outlet is also arranged at the front end, nitrogen can enter the continuous degradation device through the nitrogen inlet and carry the generated dimethylcyclosiloxane mixture out of the continuous degradation device, so that the dimethylcyclosiloxane mixture is prevented from staying in the continuous degradation device for too long time, and the nitrogen also plays a role in adjusting the temperature in the continuous degradation device. Together with the heating of the heat medium, the temperature of the continuous degradation device can be more accurately controlled, so that the degradation efficiency is further improved.

[0019] The gaseous product enters a liquid separation cooling device, and the liquid separation cooling device is a conventional cooling device in the field, which can refer to conventional equipment in the existing DMC industry, and the inventors will not repeat it here.

[0020] After the degradation is completed, the material falls off through the friction and collision of the solid heat carrier, is sealedly discharged from the discharge port of the continuous degradation device, and enters the water-cooled conveyor through the discharge machine for further heat exchange and cooling. The finally obtained solid product can be calcined according to the existing process, so that the carbon element in the solid product is removed, and high-purity silicon dioxide is obtained, which can be used as a raw material for processing silicone rubber.

[0021] As described above, the waste silicone rubber and the catalyst are pre-reacted in the stirred reactor, the reaction product is introduced into the continuous degradation device after the pre-reaction is completed, and the solid heat carrier is used to rapidly disperse and heat the reaction product, so that the continuous feeding of the continuous degradation device is realized, the continuous degradation of the waste silicone rubber is realized, the problem of intermittent cracking in the prior art is solved, the problem of insufficient cracking caused by the decrease of the heat conduction performance due to the viscosity of the material in the prior art is avoided, and the service life of the equipment is greatly prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The flow equipment schematic diagram of the industrial continuous silicone rubber degradation process is shown in the figure, Figure 2Structure diagram of the stirring reactor, Wherein 1 is a shell, 2 is a gas outlet, 3 is a raw material inlet, 4 is a second heat medium outlet, 5 is a second heat medium inlet, 6 is a stirring device, and 7 is a discharge port. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0024] The solid heat carrier used in the following embodiments is preferably a heat-conducting small ball, and specific reference can be made to the related technical solutions in the prior applications CN101074385A or CN108911458A. The continuous degradation device can refer to the waste rubber or plastic continuous cracking equipment described in the prior application CN101484551A, or other prior applications of the applicant, as long as a shell or outer cylinder through which the heat medium passes is provided outside the continuous cracking device. The above technical solutions are also disclosed in the prior applications of the applicant, and the inventor does not make specific limitations. The solid heat carrier can be used in a circulating manner in the continuous degradation device, or can be used in an external circulation manner. Both of them can be realized by using the existing technology, and in particular, the screening device for separating the solid heat carrier from the solid product in the prior application of the inventor can be selected. The inventor does not repeat the description.

[0025] Embodiment 1 As shown in the figure, an industrial continuous silicone rubber degradation process, the specific steps are as follows: Figure 1 Various sources of waste silicone rubber are collected and washed, and then dehydrated and put into a raw material temporary storage bin. Then it is sent to a transition bin for further mixing and sent to a metering device. The metered material is sent to the stirring reactor through the sealed feeder, and pre-reaction is carried out in the stirring reactor. The pre-reaction material is sent to the continuous degradation device through the second sealed feeder, and the solid heat carrier is pre-installed in the continuous degradation device. After the pre-reaction material contacts with the solid heat carrier, it continuously moves from the feeding end to the discharging end of the continuous degradation device, and the degradation of the material is completed. The degraded material falls through the friction and collision of the solid heat carrier, and finally is sealed and discharged from the discharge port of the continuous degradation device. The dimethylcyclosiloxane mixture generated during the pre-reaction and continuous degradation process is discharged from the reaction device in gaseous form and converted into liquid product through the liquid separation cooling device.

[0026] Embodiment 2 ​The stirring reactor used in embodiment 1 comprises a shell 1 and a stirring device 6 arranged in the shell 1, the interior of the stirring reactor is a sealed cavity, the top is respectively provided with a raw material inlet 3 and a gas outlet 2, and the bottom is provided with a discharge port 7 which is sealingly connected with the second sealing feeder; the shell 1 is a double-layer shell, and a second heat medium inlet 5 and a second heat medium outlet 4 are arranged on the shell 1; The number of the stirring reactors is not less than 2, and the stirring reactors are arranged in parallel and are sealingly connected with the second sealing feeder through separate discharge channels.

[0027] The waste silicone rubber and the catalyst are mixed in the stirring reactor with the above structure, and pre-reaction occurs under heating, the temperature of the pre-reaction is controlled at 120-180℃, and the pre-reaction time is 1-2h; the catalyst used is concentrated sulfuric acid, and the catalyst dosage is 3% of the weight of the waste silicone rubber.

[0028] During the pre-reaction process, the waste silicone rubber starts to have a small amount of degradation reaction under the action of the catalyst, and a certain amount of gaseous products are released in the system, the gaseous products contain dimethylcyclosiloxane mixture and other gaseous products, therefore, these gaseous products need to be discharged from the stirring reactor in time and enter the liquid separation and cooling device to be converted into liquid products; in this way, the pre-reaction can be better promoted, and at the same time, due to the degradation reaction, the solid raw material is gradually converted into a fluid state, which can better promote the mixing of the waste silicone rubber and the catalyst, and it is more convenient for heat transfer, the improvement of heat transfer efficiency realizes the reduction of heating temperature, therefore, the pre-reaction temperature only needs to be 120-180℃.

[0029] The second heat medium inlet and the second heat medium outlet on the double-layer shell are used for conveying the heat medium for heating the stirring reactor, and the heat medium is the heat medium discharged from the continuous degradation device.

[0030] Embodiment 3 The material after the pre-reaction in embodiment 2 is sent into the continuous degradation device through the second sealing feeder, and the material immediately contacts the solid heat carrier and adheres to the surface of the solid heat carrier after entering the device, and the material will uniformly adhere to each solid heat carrier to form a thin layer of material because the solid heat carrier continuously moves from the material feeding end to the discharge end in the continuous degradation device; the whole continuous degradation device maintains a high temperature because the heating medium is arranged outside the continuous degradation device, and the solid heat carrier also carries heat when moving in the continuous degradation device, so the thin layer of material is heated faster and more uniformly on the surface of the solid heat carrier, therefore, the material after the pre-reaction starts to have a degradation reaction as soon as it contacts the solid heat carrier, and the degradation process is accelerated by the movement and collision of the solid heat carriers, thereby releasing more dimethylcyclosiloxane mixture and other gaseous products.

[0031] The further inventors control the temperature in the continuous degradation device at 180-220°C, and the residence time of the material in the continuous degradation device is controlled at 0.5-1h. The further inventors preferably control the temperature in the continuous degradation device at 180-200°C.

[0032] The continuous degradation device is also provided with a hot medium inlet and a hot medium outlet. The hot medium for heating the continuous degradation device can be molten salt or heat conducting oil, as long as it can provide the required heat for the continuous degradation device, and the hot medium can be more conveniently continuously fed into the double-shell of the stirred reactor to provide heat for the pre-reaction. The hot medium discharged from the stirred reactor is returned to the hot medium heating device to be heated and then continuously heats the continuous degradation device. The waste flue gas in the hot medium heating device can be directly used as the heat source for cleaning and dewatering the collected waste silicone rubber from various sources in Example 1, and the waste silicone rubber is dried.

[0033] In the continuous degradation device, due to the rapid degradation process, more dimethylcyclosiloxane mixture and other gaseous products are released, and the yield of these products is higher in the front reaction zone of the continuous degradation device, which makes the concentration of dimethylcyclosiloxane mixture and other gaseous products in the upper space of the front reaction zone higher. In order to avoid further cracking or side reactions of these products due to too long residence time in the continuous degradation device, a gaseous product outlet is provided at the front end of the continuous degradation device in this embodiment. In this way, the dimethylcyclosiloxane mixture and other gaseous products can be discharged from the continuous degradation device through the outlet and enter the liquid separation and cooling device as gaseous products produced by pre-reaction to be converted into liquid products.

[0034] Example 4 A nitrogen inlet is also provided at the discharge end of the continuous degradation device, which is connected to a nitrogen storage tank. Nitrogen can enter the continuous degradation device through the nitrogen inlet and carry the generated dimethylcyclosiloxane mixture out of the continuous degradation device, avoiding its long residence time in the continuous degradation device. At the same time, nitrogen also plays a role in adjusting the temperature in the continuous degradation device. Together with the hot medium heating, it can more accurately control the temperature of the continuous degradation device, thereby further improving the degradation efficiency.

[0035] The gaseous products enter the liquid separation and cooling device, which is a conventional cooling device in the art, and can refer to the conventional equipment in the existing DMC industry. The inventors do not repeat it here.

[0036] The material after degradation is dropped by friction and collision of solid heat carrier, finally sealed from the discharge port of the continuous degradation device, and enters the water-cooled conveyor for further heat exchange and cooling through the discharge machine. The final solid product can be roasted according to the existing process, so as to remove the carbon element in the solid product, that is, a high-purity silicon dioxide can be obtained, which can be used as a raw material for processing silicon rubber.

[0037] The above merely describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. An industrial continuous silicone rubber degradation process, characterized in that, The specific steps are as follows: Waste silicone rubber from various sources is collected, cleaned, dehydrated, and then sent to a raw material storage silo. After that, it is transported to a transition silo for further mixing and then sent to a metering device. The metered material is fed into the stirred reactor through a sealed feeder for pre-reaction. The pre-reacted material is fed into the continuous degradation device through the second sealed feeder. The continuous degradation device is pre-loaded with a solid heat carrier. After the pre-reacted material comes into contact with the solid heat carrier, it moves continuously from the feed end to the discharge end of the continuous degradation device to complete the degradation of the material. After degradation, the material falls off due to friction and collision with the solid heat carrier and is finally sealed and discharged from the discharge port of the continuous degradation device. The dimethylcyclosiloxane mixture generated during the pre-reaction and continuous degradation processes is discharged from the reaction device in gaseous form and then converted into a liquid product through a liquid-liquid separation and cooling device.

2. The industrial continuous silicone rubber degradation process according to claim 1, characterized in that, The stirred reactor used includes a shell (1) and a stirring device (6) installed inside the shell (1). The stirred reactor (6) has a sealed cavity inside, with a raw material inlet (3) and a gas outlet (2) respectively installed at the top, and a discharge port (7) installed at the bottom. The discharge port (7) is sealed to the second sealed feeder. The shell (1) is a double shell, and a second heat medium inlet (5) and a second heat medium outlet (4) are installed on it. The number of stirred reactors is no less than two, and each stirred reactor is set in parallel. Each of them is sealed to the second sealed feeder through a separate discharge channel.

3. The industrial continuous silicone rubber degradation process according to claim 1 or 2, characterized in that, Waste silicone rubber and catalyst are mixed in a stirred reactor and pre-reacted under heating conditions. The temperature of the pre-reaction is controlled at 120-180℃ and the pre-reaction time is 1-2 hours. The catalyst used is selected from concentrated sulfuric acid or dodecylbenzene sulfonic acid, and the amount of catalyst used is 1-5% of the weight of waste silicone rubber.

4. The industrial continuous silicone rubber degradation process according to claim 1, characterized in that, The solid heat carrier is selected from thermally conductive microspheres; the temperature in the continuous degradation device is controlled at 180-220℃, and the residence time of the material in the continuous degradation device is controlled at 0.5-1h.

5. The industrial continuous silicone rubber degradation process according to claim 1 or 4, characterized in that, The temperature inside the continuous degradation device is controlled at 180-200℃.

6. The industrial continuous silicone rubber degradation process according to claim 1, characterized in that, The continuous pyrolysis unit is also equipped with a heat medium inlet and a heat medium outlet; the heat medium is molten salt or heat transfer oil; the front end of the continuous degradation unit is equipped with a gaseous product outlet.

7. The industrial continuous silicone rubber degradation process according to claim 1, characterized in that, A nitrogen inlet is also provided at the discharge end of the continuous degradation device and connected to a nitrogen storage tank; nitrogen enters the continuous degradation device through the nitrogen inlet and carries out the generated dimethylcyclosiloxane mixture from the continuous degradation device.

8. The industrial continuous silicone rubber degradation process according to claim 1, characterized in that, After degradation, the material is sealed and discharged from the outlet of the continuous degradation device, and then enters the water-cooled conveyor for further heat exchange and cooling. The final solid product is then roasted.

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