RU2816135C1 - Tire pyrolysis reactor - Google Patents

Abstract

FIELD: various technological processes.

SUBSTANCE: invention relates to processing of tires by pyrolysis using liquid metal coolant. Tire pyrolysis reactor consists of housing with loading part, including neck, and container filled with liquid metal coolant, which is its active part, devices for feeding tires into the reactor, heating devices, devices for removing bead cord, breaker and studs, device for forced air extraction from tires, located above the loading part of the reactor and made in the form of a drilling head for tires. Housing is made U-shaped with possibility of formation of hydraulic lock when it is filled with liquid metal heat carrier and is made of corrosion-resistant heat-resistant steel. In the loading part, above the neck, there is a ramp and a device for feeding tires into the reactor, which is a mechanism of a three-link hinge-lever parallelogram. Device for removal of bead cord, breaker and studs is located in the device for feeding tires into the reactor and is made in the form of a scraper-type extractor. Heating device is located under the loading and active parts of the reactor, and at the end of the active part there is a mesh limiter and a flue gas discharge pipe, as well as a pipe for output of pyrolysis gases, connected to a condenser, which in turn is connected through a vacuum pump to a heating device for their use as a combustible substance, and the other condenser pipe in its lower part is connected to a pyro oil tank.

EFFECT: complete removal of atmospheric air with possibility of tire supply for pyrolysis in depth of liquid metal heat carrier, creation of pressure difference in volume of active part and atmospheric pressure acting on liquid metal coolant in loading part of reactor, which determines the tire pyrolysis process continuity.

9 cl, 5 dwg

Description

The invention relates to the field of processing tires by pyrolysis using a liquid metal coolant.

Various devices are known for processing rubber and polymer materials by pyrolysis. For example, an invention is known under patent No. 2693800 entitled “Device for recycling waste from rubber and polymer materials” (IPC: F23G 5/027; C10B 53/07). The device contains a reactor tank, a compressed gas cylinder, an upper pipeline, a removable cassette, a gas reducer, a gas pipeline and a neck. In addition, the device contains a detail for fixing the position of the removable cassette, a bottom, a liquid metal coolant, shut-off valves, a condenser, a discharge line for non-condensable gaseous products, a heater, a lower pipeline, a shell, an outlet pipeline, a separator, a removable cover and thermal insulation. The disadvantages of this product are that the device requires a lot of manual labor, during operation of the device there are large losses of thermal energy and high gas consumption to move the coolant from one reactor tank to another, there is no separation of solid pyrolysates, such as steel and pyrolytic carbon. In addition, in the design of the device, the removable cassette slows down heat transfer, which in turn slows down the process of pyrolysis of raw materials. When the device is operating, a significant amount of lead vapor is present in the air in its working area. This is due to a difference of more than 100°C between the coolant temperature (450°C) and its melting point (327°C). Lead is toxic and a potential carcinogen for the human body, the maximum permissible concentration for lead compounds in atmospheric air is 0.003 mg/m³.

The closest analogue to the claimed invention (prototype) in terms of the totality of existing features is a tire pyrolysis reactor, described in the invention entitled “Process and system for pyrolysis of whole tires and plastic composites for the purpose of converting fuel and recovering components” according to patent No. EP2890763 (IPC: C10B49 /14; C10B53/07; C10G1/10). The prototype contains: means for loading said starting material into a loading vessel, said loading vessel designed to remove air from said starting material; means for loading said starting material from said loading vessel into the pyrolysis chamber; a pyrolysis chamber in which a pyrolysis liquid is stored, in which said pyrolysis liquid is molten zinc or tin; means for allowing heavy and light solid pyrolysis products associated with said starting material to be separated within said pyrolysis liquid so that light solid pyrolysis products and pyrolysis vapors are separated from the top of said pyrolysis liquid; means for removing any pyrolysis vapors and said light solid pyrolysis products using an extractor from the surface of said pyrolysis liquid; means for separating said pyrolysis vapors and said light solid pyrolysis products; condenser system for condensing vapor into liquid; and means for removing said heavy pyrolysis solids from the bottom of said pyrolysis chamber using a removal device, and wherein said pyrolysis chamber comprises an inclined bottom such that said heavy pyrolysis solids collect at a low point of said pyrolysis chamber. The disadvantage of this tire pyrolysis reactor is the incomplete removal of atmospheric air located in the tires sent to the active part of the reactor. In the prototype reactor, preventing atmospheric air from entering the active part of the reactor is carried out as follows. The tire is placed in an atmospheric airlock, then the air in the airlock is pumped out with a vacuum pump. Next, the airlock is purged with nitrogen and only after that the tire is moved into the pyrolysis chamber. The tire appears floating on the surface of the molten metal, and the contact area with the liquid metal coolant will not be maximum. And this reduces the efficiency of pyrolysis and increases the process time. In addition, the removal of pyrocarbon and slag in the prototype is carried out using a vacuum extractor, periodically stopping and opening the reactor. In other words, the design of the reactor determines the intermittency of the technological process of pyrolysis of tires and other rubber products.

The task that the developer of the new tire pyrolysis reactor set for himself was to develop a device that would allow for more efficient processing of tires and other rubber products. The technical result achieved in the process of solving the problem assigned to the developer is the complete removal of atmospheric air with the possibility of supplying a tire for pyrolysis into the depth of the liquid metal coolant. In addition, the technical result is the creation of a pressure difference in the volume of the active part and atmospheric pressure acting on the liquid metal coolant in the loading part of the reactor, which determines the continuity of the tire pyrolysis process.

The essence of the invention is that in a tire pyrolysis reactor, consisting of a housing with a loading part, including a neck, and a container filled with liquid metal coolant, which is its active part, a device for feeding tires into the reactor, a heating device, a device for removing bead cord, a breaker and spikes, characterized in that it is additionally equipped with a device for forced extraction of air from the tires, located above the loading part of the reactor and made in the form of a drilling head for tires, while the body is U-shaped with the possibility of forming a water seal when filling it with liquid metal coolant, and the body is made made of corrosion-resistant heat-resistant steel, and in the loading part, above the neck, there is a ramp and a device for feeding tires into the reactor, which is a three-link articulated-lever parallelogram mechanism, and a device for removing bead cord, breaker and studs is located in the device for feeding tires into the reactor and is made in the form scraper-type extractor, the heating device is located under the loading and active parts of the reactor, and at the end of the active part there is a mesh limiter and a pipe for exhausting flue gases, as well as a pipe for pyrogases exiting, connected to a condenser, which in turn is connected through a vacuum pump to the device heating to use them as a flammable substance, and the other condenser pipe in its lower part is connected to a container for pyro-oil. At the same time, zinc is used as a liquid metal coolant in the tire pyrolysis reactor. Tire pyrolysis reactor the ramp consists of a rocker arm and a connecting rod, which are connected by a cylindrical hinge. The reactor vessel is made of steel grade 08Х18Н10Т. Liquid or gaseous fuel is used as an external fuel source. The active part of the housing in its lower part is made with a valve for draining the liquid metal coolant. At the bottom of the housing in the rear part there is a container for temporary storage of the resulting slag and pyrocarbon. The liquid metal coolant heating device is made in the form of burners or nozzles.

Evidence of the possibility of implementing the proposed tire pyrolysis reactor with the implementation of the specified purpose is given below using a specific example of a tire pyrolysis reactor. This representative example of a specific tire pyrolysis reactor according to the invention does not in any way limit its scope of legal protection. This example provides only a specific illustration of the proposed tire pyrolysis reactor.

The invention is illustrated graphically, where the following are schematically shown:

in fig. 1 - tire pyrolysis reactor, front view;

in fig. 2 - aka, top view;

in fig. 3 - ramp in a raised state, front view;

in fig. 4 - automatic loading machine, side view;

in fig. 5 - grip washer.

The tire pyrolysis reactor includes a U-shaped body 1 made of corrosion-resistant heat-resistant steel, for example, steel grade 08Х18Н10Т. U-shaped housing 1 consists of boot 2 and active 3 parts. The active part of the U-shaped housing 1 is filled with liquid metal coolant 4, for example, molten zinc. The loading part 2 of the reactor, intended for loading tires, has a neck 5, above which there is a ramp 6 and a tire feeder in the form of an automatic loading device 7, as well as a device 8 for forcibly extracting air from the tires. In this particular embodiment, the device 8 for forcibly extracting air from the tires is made in the form of a drilling head, although it can be made in the form of a puster or other similar devices. The ramp 6 is located above the surface 9 of the liquid metal coolant 4, which is in the tire loading position, as shown in FIG. 1, closes the neck 5 of the loading part 2 of the reactor. In fig. 3, the ramp 6 is shown in a raised position and consists of a rocker arm 10 and a connecting rod 11, which are connected by a cylindrical hinge 12. The rocker arm 10 is fixed to the end wall of the reactor using a cylindrical hinge 13, while its center is located above the end of the connecting rod 11. The end wall of the reactor vessel Above ramp 6 there is an opening for supplying tires to the loading area. The end of the rocker arm 10 is connected to a pneumatic cylinder 14, designed to raise the ramp 6. The end of the connecting rod 11, designed to move along the guide 15, ensures the opening of the surface 9 of the liquid metal coolant 4. The loading machine 7 is a three-link parallelogram mechanism. The rocker arm 16 of the automatic loading device 7 is connected to the electric motor 17 through a gearbox 18 and a drive shaft 19. The gripping washer 20 of the connecting rod 21 is designed in circular box-shaped guides 22 located on the side wall 23 inside the reactor housing 1. The jaws 24 are designed to grip tires using pneumatic cylinders 25. The wall 23 of the housing with circular box-shaped guides 22 forms with the connecting rod 21 a two-moving plane kinematic pair of the 4th class and thereby ensures the movement of the gripping washer 20 with the tire in an arc. The length of the rocker arm 16 is equal to the median radius of the circular box-shaped guides 22. The guides 15 and 22 are located on opposite side walls of the reactor. The straight part of the connecting rod 21 and the rocker arm 16 are designed outside the reactor, and the curved part of the connecting rod 21 with the gripping washer 20 is designed inside the reactor. In the gripping washer 20 of the loading machine 7 there is an extractor 26 with a pneumatic cylinder 27. The extractor 26 is designed to remove bead cord, breaker and spikes from the liquid metal coolant 4. To maintain the required temperature of the liquid metal coolant 4, a heating device in the form of burners 28 is placed under the loading 2 and active 3 parts. For this purpose, any fuel source can be used: non-condensed pyrogases, pyro-oil, pyrocarbon, and in any combination. For the initial melting of the liquid metal coolant 4, gas is provided from an external fuel source 29. At the end of the active part 3, a chimney 30 is designed for the removal of flue gases and an outlet pipe 31 for the exit of pyrogases. At the bottom of housing 1, in its rear part, a container 32 is installed for temporary storage of the resulting slag and pyrocarbon. At the end of the active part 3, in the area of the surface of the liquid metal coolant 4, a mesh limiter 33 is mounted, designed to prevent the floating of pyrolyzed pieces of rubber freed from the cord, breaker and studs. The outlet pipe 31 for the exit of pyrogases is connected to a condenser 34, designed to separate the pyrogases into pyro-oil and non-condensable pyrogases. Valve 35 is designed to drain the liquid metal coolant 4. The vacuum pump 36 is designed to create a reduced pressure in the volume above the surface of the liquid metal coolant 4 in the active part 3 and atmospheric pressure acting on the liquid metal coolant 4 in the loading 2 part of the reactor. Burners 28 are connected by a pipeline to a vacuum pump 36 to supply the burners with non-condensable pyrogases. The U-shaped reactor vessel 1 and the liquid metal coolant 4 create a water seal that prevents atmospheric air from entering the active 3 part of the reactor. Thus, structurally, the loading part 2 of the described reactor is made with the possibility of supplying tires by the automatic loading device 7 to the active part 3 of the housing 1 from below. The design of the inventive tire pyrolysis reactor provides at the end of the active part 3 of housing 1 an internal end wall 40. At the bottom of the condenser 34 there is mounted a pipe 37 for draining the pyrolysis oil into a container 38. Under the loading part 2 of housing 1 there is a container 39 for collecting cord, breaker and studs.

The tire pyrolysis reactor operates as follows. Pieces of zinc are loaded through the neck 5 of the loading part 2 of the reactor vessel 1. Then the burners 28, powered by gas from an external source 29, are ignited to heat the pieces of zinc of the liquid metal coolant 4. As the zinc melts, the following pieces are added. Then, after filling the neck 5 of the loading part 2 of the reactor vessel 1 with liquid metal coolant 4, the vacuum pump 36 is started. This is necessary to create a difference in the surface levels 6 of the liquid metal coolant 4 in the loading part 2 and in the active part 3 of the reactor. As the liquid metal coolant melts and its level rises due to the operation of the vacuum pump 36 in the tire pyrolysis reactor housing 1, a pressure difference will be formed in the volume of the active part 3 and the atmospheric pressure acting on the liquid metal coolant 4 in the loading part 2 of the reactor. Due to the difference in the levels of liquid metal coolant 4 in the loading 2 and active 3 parts of the reactor, in the loading 2 part of the reactor there will be a significantly smaller volume of liquid metal coolant 4, and the height of the loading 2 part of the reactor will be correspondingly smaller. The liquid metal coolant 4 is heated to 450-480°C. After the start of the pyrolysis process, maintaining the required temperature of the liquid metal coolant 4 in both parts of the reactor is ensured by burning non-condensed pyrolysis gases. After heating the liquid metal coolant 4 to the required temperature, begin loading the tires. The tire intended for pyrolysis using an automatic machine 7 is fed through the neck 5 onto the ramp 6, which is in its original position, as shown in Fig. 1. As a result, the tire rolls all the way into the reactor wall. After this, the jaws 24 of the gripping washer 20, driven by pneumatic cylinders 25, expanding radially (Fig. 5), grab it by the sole. Using device 8 for forcibly extracting air from tires, the tire tread is drilled through. Next, the rocker arm 10, driven by the pneumatic cylinder 14, moving to a vertical position together with the connecting rod 11, opens the surface 9 of the liquid metal coolant 4. The automatic loading device 7, driven by the electric motor 17 through the gearbox 18, immerses the tire into the liquid metal coolant 4 of the loading 2 part of the reactor, bringing the tire to the end of the guides 22, which are already in the active 3rd part of the reactor, where the pyrolysis process occurs. During the process of immersing the tire in the liquid metal coolant 4, air comes out of it. Then the jaws 24 of the grip washer 20 release the tire sole. The extractor 26, driven by the pneumatic cylinder 27, moves from its initial position to the working position. The loading machine 7, returning to its original position, uses an extractor 26 to remove the bead cord, breaker and spikes from the bottom of the loading 2 part of the reactor, through the upper edge of the neck 5. Next, the loading machine 7 and the extractor 26 take their original position. After this, the ramp 6 is lowered, which takes its original position. The reactor is ready to load the next tire. Under the influence of the molten metal of the liquid metal coolant 4 in the absence of oxygen, the process of pyrolysis occurs, that is, thermal destruction of rubber. During the destruction process, pyrolytic gases are released, leaving the reactor upward into the outlet pipe 31. Pyrocarbon is also released, which floats to the surface of the liquid metal coolant 4 and is removed through the upper edge of the end wall 40 of the reactor housing 1 and which enters the receiving tank 32. In addition This results in the release of the metal cord, breaker and spikes from the rubber, which sink in the liquid metal coolant 4 and they roll down along the bottom of the reactor housing 1, subsequently removed by the extractor 26. Next, the pyrolyzed pieces of rubber, freed from the cord, breaker and spikes, float into the liquid metal coolant 4 and rest against mesh 33, where the pyrolysis process comes to an end. The pyrogen gases leaving the reactor into the outlet pipe 31 are sent through a pipeline to the condenser 34, where they are separated into two fractions: condensed pyro-oil and non-condensed pyrogen gases. Non-condensed pyrogases from condenser 34 are sent through a pipeline to burners 28 to maintain the required temperature in the reactor. The pyromas oil from the condenser 34 is removed through the pipe 37 into the container 38. The flue gases formed as a result of combustion, washing the lower heating surface of the reactor vessel 1, rush upward through the chimney 30. If necessary, the liquid metal coolant 4 is drained from the reactor through valve 35 (Fig. 2 ), located in the lower part of the reactor vessel 1.

Compared to the prototype reactor, the described reactor does not have an atmospheric airlock, a conveyor, atmospheric airlock doors and their drives, a vacuum air pump, or a nitrogen supply line. There are no nitrogen costs. In addition, losses of thermal energy and labor costs are reduced, the quality of pyrolysates is improved, and environmental safety is increased. The new tire pyrolysis reactor reduces the loss of thermal energy during pyrolysis. This is ensured by the absence of cooling stages in the pyrolysis process after the completion of pyrolysis of the previous volume of rubber and subsequent heating of the next volume of rubber. At the same time, labor costs are reduced by minimizing manual labor, while loading of raw materials, unloading and separation of pyrolysis products is carried out automatically without stopping the pyrolysis process. It is necessary to note the improvement in the quality of pyrolysates, which is ensured by a higher heating rate of the raw materials, and leads to an increase in low molecular weight pyrolysates, compared to processes in the known prototype installation. The time of the pyrolysis process is also reduced, the secondary conversion of pyrolysates is reduced, since a long time of their stay in a high-temperature zone promotes the secondary conversion of pyrolysis products, increasing the yield of undesirable products such as coke, tar, and other undesirable temperature-resistant products. The intensity of heating of raw materials helps to improve the quality of pyrolysates. Condensation of substances that form coke is reduced. In pyro-oil, the yield of isoprene increases, and the loss of dipentene, which is characterized by chemical instability at elevated temperatures, is reduced, and the diesel fraction increases. In pyrocarbon, pore blockages are reduced, which leads to an increase in surface area, and therefore to an improvement in the properties of pyrocarbon as a sorbent. The large heat capacity of the liquid metal coolant provides a significant time constant in the liquid metal coolant temperature control loop; the controlled heat supply from the burners is guaranteed to maintain the required coolant temperature. In this case, the stability (fluctuations) of the temperature of the liquid metal coolant will be reduced to a range of no more than 10°C, which improves the quality of the pyrolysates. Increased environmental safety is ensured by the absorption of sulfur in the raw material by the metal of the liquid metal coolant, which significantly reduces the formation of sulfur dioxide in flue gases.

Claims (9)

1. A tire pyrolysis reactor, consisting of a housing with a loading part, including a neck, and a container filled with liquid metal coolant, which is its active part, a device for feeding tires into the reactor, a heating device, a device for removing bead cord, breaker and studs, characterized in that additionally equipped with a device for forced extraction of air from the tires, located above the loading part of the reactor and made in the form of a drilling head for tires, while the housing is U-shaped with the possibility of forming a water seal when filled with liquid metal coolant, and the housing is made of corrosion-resistant heat-resistant steel , and in the loading part above the neck there is a ramp and a device for feeding tires into the reactor, which is a three-link hinge-lever parallelogram mechanism, and a device for removing bead cord, breaker and studs is located in the device for feeding tires into the reactor and is made in the form of a scraper-type extractor, the device heating is located under the loading and active parts of the reactor, and at the end of the active part there is a mesh limiter and a pipe for exhausting flue gases, as well as a pipe for pyrogases outlet, connected to a condenser, which in turn is connected through a vacuum pump to a heating device for use in as a flammable substance, and the other condenser pipe in its lower part is connected to a container for pyro-oil. 2. The tire pyrolysis reactor according to claim 1, characterized in that zinc is used as a liquid metal coolant. 3. Tire pyrolysis reactor according to claim 1, characterized in that the ramp consists of a rocker arm and a connecting rod, which are connected by a cylindrical hinge. 4. The tire pyrolysis reactor according to claim 1, characterized in that the reactor body is made of steel grade 08Х18Н10Т. 5. The tire pyrolysis reactor according to claim 1, characterized in that liquid or gaseous fuel is used as an external fuel source. 6. The tire pyrolysis reactor according to claim 1, characterized in that the active part of the housing in its lower part is equipped with a valve for draining the liquid metal coolant. 7. The tire pyrolysis reactor according to claim 1, characterized in that at the bottom of the housing in the rear part there is a container for temporary storage of the resulting slag and pyrolytic carbon. 8. The tire pyrolysis reactor according to claim 1, characterized in that the liquid metal coolant heating device is made in the form of burners. 9. The tire pyrolysis reactor according to claim 1, characterized in that the liquid metal coolant heating device is made in the form of nozzles.