LV13724B - Installation for processing of automobile tyre covers and other wastes containing rubber - Google Patents

Abstract

The invention concerns technology of processing industrial and household wastes of rubber and automobile tyre covers. Installation for processing automobile tyre covers and others rubber-containing wastes differs from other installations by means of the top part of the chamber of pyrolysis which is executed in the form of two - external and internal, coaxially located - pipes with apertures on lateral walls of both pipes connected by gas exhaust tubes, so that space between external and the internal pipe, forming the heat transfer chamber, is separated from the space formed by an external surface of an external pipe by internal surfaces of taking away tubes and internal surface of an internal pipe, being working zone of a reactor, and in heating system of rubber-containing wastes is additionally entered the system of preliminary heating of rubber-containing wastes, containing the chamber of a heat transfer with torches, possessed in its bottom part, at height of 0,5-2 internal diameters of chambers of a heat transfer from the top border of an active zone. Installation is additionally supplied by the system of hashing and moving of rubber-containing wastes in a reactor, and also means for inert gas supercharging in the loading chamber of rubber-containing wastes and the unloading chamber of firm products of pyrolysis.

Description

Technical field

The invention relates to a technology for the recycling of automotive tires and rubber for industrial and municipal waste, and can be used in the energy fuel complex, lacquer and paint and technical rubber industries, recycling plants and recycling of raw materials and waste.

State of the art

There is a known process for the thermal treatment of end-of-life tires, which includes loading them into a reactor, pyrolysis the material with further product decomposition, and unloading the solid residue. Pyrolysis is carried out at temperatures up to 1000 ° C in a reducing gas medium (GB 1481352, published July 27, 1977)

A method of recycling end-of-life tires with a vacuum pyrolysis of 490 ° C to 510 ° C and an absolute pressure of less than 5 kPa to produce carbon black with an iodine absorption of 0.13 to 0.15 kg / kg with an oil content of DBF (80) is known. -100) from 10 to 5 m 3 / kg and a coloring amount from 55 to 63 (U.S. Pat. No. 5,087,436, issued Feb. 11, 1992).

A common disadvantage of the above techniques is the complex hardware design of the process and the high power consumption of the process. In addition, the resulting carbon black is of very low quality.

There is also a known method of heat treatment of used tires (patent RU 2139187, published 10.10.1999). Using this technique, the spent tires are loaded into the reactor, pyrolysis of the material at a temperature of 550 ° C to 800 ° C in a reducing gas medium with a ratio of reducing gas to material of 0.20 to 0.45: 1. The pyrolysis products are further broken down and the solid residue is discharged. At the end of the pyrolysis, superheated steam from 250 ° C to 300 ° C is introduced, with a ratio of 0.003 to 0.12: 1 to the material to be loaded. The reducing gas is obtained by the incomplete hydrocarbon combustion process from = 0.4 to 0.085. The technique enables the reduction of energy consumption, the simplification of the recycling process of worn tires, the obtaining of high quality soot for reuse in the production of rubber compounds. The disadvantage of this invention is that the manufacturing process is interrupted at the expense of the complete discrete supply of the tires to the reactor, which results in a slower pyrolysis of the heat mass exchange process and an increase in power consumption, which in turn affects the quality of production.

A method of recycling waste gas such as end-of-life tires or similar rubber waste is known (patent RU 2062284, published June 20, 1996), which involves loading into a reactor batch (consisting at least partially of combustible waste pieces for pyrolysis and gasification) through a loaded batch such that an oxygen-containing gasifying agent is introduced into the reactor and gaseous and liquid processing products are removed from the reactor. In addition, the reactor maintains a maximum temperature of between 800 ° C and 1700 ° C.

There is a known method of recycling used tires (patent RU 2142357, published

10.12.1999) containing thermal decomposition from 400 ° C to 600 ° C with formation of vapor gas products and solid carbon residues, their cooling from 40 ° C to 50 ° C, separation into liquid and vaporous phases and solid carbon residues at it is then quenched by evaporation of the pyrolysis water with the addition of gaseous ammonia to the cooling zone.

Techniques for recycling end-of-life tires (Patent Nos. RU 2062284 and RU 2142357) are known in which the recycling of tires is accomplished in the presence of an oxygen-containing gaseous agent fed into a recyclable material, i.e., oxidizing gas, which increases the material's energy consumption.

Much closer in technical terms is a facility for disposing of rubber-containing wastes, especially automotive tires (patent UA 7534U, published June 15, 2005), comprising a reactor with a hermetically sealed pyrolysis chamber, rubber-containing loading and solid pyrolysis product discharge systems and heating the rubber-containing waste to a pyrolysis temperature, separating and purifying the liquid and gaseous products of the pyrolysis by feeding a portion of the pyrolysis-gas product to the rubber-containing waste heating system. The pyrolysis chamber is designed in the form of a vertical column, the system for loading rubber-containing wastes and the discharge of solid pyrolysis products in the form of hermetically sealed loading and unloading tanks, each fitted with a sealing pivotable top and bottom lid. The technical rubber waste heating system shall be designed in the form of a combustion chamber located above the unloading tank with an outer barb and at least one gas burner outlet open to the combustion chamber. The unit is equipped with a gas expander located below the loading tank which is connected to the outlet of the pyrolysis liquid and gaseous product separation and purification system.

The disadvantage of this device is that the pyrolysis reaction occurs only in the direct burner heating area, which results in pyrolysis with a small amount of rubber-containing waste. The feedstock layer, which is higher than the combustion chamber, heats up considerably worse due to the column height, which is almost 8 times the diameter.

As a result, the plant has a low throughput of rubber waste. Another major disadvantage of this unit is that the poor warming of the rubber-containing raw materials above the burner working area may cause the rubber-containing raw materials to become stuck when unloading solid waste from the unloading tank. The gravitational force, which causes the rubber-containing raw materials to move downward, regularly proves to be insufficient to overcome the frictional force in contact with the column edges. In the operation of similar equipment, this leads to the need to open the unloading chamber and to facilitate the unloading of solid pyrolysis products by mechanical means associated with an increased risk to the person carrying the solid pyrolysis product (unloading temperature above 300 ° C) and soot dust. mechanical unloading. At the same time, the sealing of the reactor itself is disrupted, which leads to a leaping oxygen working area of the burners, which in turn leads to a strong increase in soot slag in the liquid and gaseous pyrolysis products.

A third major disadvantage is that the gaseous products of the combustion of the gas burner enter the heating system and the flame at the outlet of the unit 5. During the combustion of these gases, carbon dioxide is produced in the burner, which is not separated in the separation and purification system of the liquid and gaseous waste. As a result, with each new movement of the gas stream through the cycle: reactor - separation - purification - heating system - reactor Pyrolysis gaseous products increase carbon content. For this reason, the ability to control the temperature in the reactor area also deteriorates and the pyrolysis process periodically begins to exceed the temperature range of 400 ° C to 600 ° C, which is optimized by the authors of this equipment. As a result, the percentage of liquid fraction at the outlet of this unit deteriorates and the concentration of substances that are particularly harmful to health, such as phenols, furans, benzopyrenes, benzenes and dioxins, increases rapidly in gaseous products.

Disclosure of the Invention

The object of the present invention is to increase the efficiency, as well as the operational and environmental safety, of automotive tires and other rubber-containing waste equipment. The stated aim is achieved by changing the design of the device.

The machine for recycling automotive tires and other rubber-containing waste comprises a reactor with an airtight pyrolysis chamber, a device for supplying rubber-containing waste, a device for unloading solid pyrolysis products, a heating system for rubber-containing waste to a pyrolysis temperature for pyrolysis solid rubber-containing products. in the form of a chamber with an outer rod and at least one burner outlet open to the combustion chamber, a system for separating and purifying the liquid and gaseous pyrolysis products with systems for feeding the pyrolysis gaseous products in a rubber-containing waste heating system; in the form of outer coaxial tubes with openings in the side walls of both tubes connected by gas-discharge tubes so that the space between the inner and outer tubes forming the heat transfer chamber is separated consisting of a space consisting of the outer surface of the outer tube, the inner surface of the discharge tubes and the inner surface of the inner tube forming the reactor working area, but the rubber waste heating system additionally includes a rubber waste preheating system containing a heat transfer chamber burners. The burners are tangent to the diameter of the inner tube at opposite points and have vectors facing each other. The previous rubber-containing waste heating system provides pyrolysis in a large mass of rubber-containing waste compared to the prototype. The waste shifts better in the core than in the prototype because it is pre-heated and therefore has a lower coefficient of friction against the reactor wall than unheated rubber-containing waste. In addition, the use of the proposed pre-heating system for rubber-containing waste prevents the combustion products from mixing with the pyrolysis gases, resulting in an improved liquid fraction percentage at the outlet and a reduction in the concentration of harmful substances (phenols, furans, benzopyrenes, benzenes and dioxins).

The equipment is additionally equipped with a rubber-containing waste mixing and transfer device located vertically in the upper part of the pyrolysis chamber (in the reactor working area). The device for mixing and transferring rubber-containing waste is designed in the form of a screw with a blade diameter of 0.3 to 0.9: 1, preferably 0.5 to 0.7: 1, relative to the internal diameter of the reactor working area. The proposed device for mixing and transferring rubber-containing waste allows the waste to be mixed until it reaches the reactor core, contributing to its uniform heating, which significantly increases the rate of pyrolysis of the current dose of rubber-containing waste and, consequently, increases system productivity. Waste disposal prevents rubber-containing waste from sticking and burning to the reactor walls, which increases the operational safety of the plant.

In order to prevent atmospheric air from entering the reactor during loading of rubber waste or discharge of solid pyrolysis products, the rubber waste loading chamber and pyrolysis solid product discharge chamber shall be provided with devices for injection of inert gas, which reduces the amount of soot slag in pyrolysis liquid and gaseous products.

The invention is further illustrated by the following exemplary embodiment of the invention 5, which is illustrated by a diagrammatic representation of a reactor for a recycling plant for automotive tires and other rubber-containing waste.

Equipment for recycling automotive tires and other rubber-containing waste comprises a reactor (1) with an airtight pyrolysis chamber (2) connected to a device for supplying rubber-containing waste (not shown), a device for unloading solid pyrolysis products (not shown) provided with heating the rubber-containing waste to a pyrolysis temperature in the form of a solid pyrolysis product combustion chamber (3) located above the unloading chamber (4) and having at least one burner (6) having an open outlet in the combustion chamber (4). The reactor (1) is connected to a known pyrolysis liquid and gaseous product separation and purification system and a part pyrolysis gaseous product feed system (not shown) in a rubber-containing waste heating system. The upper part of the pyrolysis chamber (2) is formed in the form of two inner and outer coaxially arranged tubes with openings in the side walls of both tubes connected to the gas discharge tubes (7) so that the space between the external and internal tubes forming the heat supply chamber (8) , is separated from the space formed by the inner surface of the inner tube, the inner surfaces of the gas discharge tubes (7), and the inner surface of the inner tube, which forms the reactor working area (9). Thus, the reactor working area (9) and the heat supply chamber (8) are completely isolated from each other. The rubber-containing waste heating system further comprises a rubber-containing waste pre-heating system comprising a heat supply chamber (8) with two burners (6 ') disposed at its lower part. The burners (6 ') are placed tangentially to the diameters of the inner tube at opposite points and their vectors are directed against each other. Ideally, the burners (6 ') are mounted between 0.5 and 2 inside diameter of the heat supply chamber (8) at a height above the upper limit of the active zone (13). This arrangement of the burners enables the pyrolysis process to be optimized. The upper part of the heat-supply chamber (8) contacts the rubber-containing waste (lock) chamber (10) in such a way that the combustion products from the burners (6 ') move to heat the lock-loading chamber (10) and pass through the short pipe (11) for gases from the heat transfer chamber leading to the exhaust gas cleaning unit (not shown). The heat supply chamber (8) is enclosed by a reactor heat shield (12) for insulating processes occurring in the working area (9) and the area between the sheath (12) and the heat supply chamber (8).

In the lower part of the reactor, the working zone (9) passes through the reactor core (13), where the rubber-containing waste is heated directly through the outer rod (5) by a burner (6) positioned relative to the pipe diameter of the core (13). ).

At the top of the reactor is a pyrolysis gas outlet conduit (14).

The inner tube of the heat supply chamber (8) has a larger diameter at the level of the burners (6 ') than the portion of the upper heat supply chamber (8) which allows to maximize combustion work in the burner working area without changing the shape of the inner cylindrical tube.

The apparatus is further provided with a device for mixing and transferring rubber-containing waste (15), which is positioned vertically in the upper part of the pyrolysis chamber (2) (in the reactor working area (9)). The apparatus for mixing and transferring rubber-containing waste (15) is provided in the form of a screw having a blade diameter to the inner diameter of the reactor working area (9) of 0.3 to 0.9: 1, preferably 0.5 to 0.7: 1 . The length of the working surface of the auger is such that it does not extend downwards to the upper limit of the core (13) (preferably from 0.5 to 1.5 of the internal diameter of the heat chamber) but from the top to the lower loading chamber (10) border. The device for mixing and transferring rubber-containing waste (15) is arranged so that the force supports and the bearings that enable it to rotate are hermetically insulated from the working area (9) and the reactor jacket (12) in the heat-supply chamber (8). speed implements a power motor (16) driven by a device control unit (not shown). The rotation of the auger rotates the rubber-containing waste before it enters the reactor core (13) for uniform preheating, transferring the rubber-containing waste during loading and unloading operations, and prevents trapped rubber-containing waste from getting stuck in the work area (9).

For preventing the entry of atmospheric air into the reactor (1) during loading of rubber-containing wastes or unloading of pyrolysis solid products, the (sluice) rubber-containing waste loading chamber (10) and (sluice) pyrolysis solid product unloading chamber (3) are provided with inert gas injection devices (17) .

This is how the device works. The rubber-containing waste, comminuted from about 100 mm to about 200 mm, is placed in the previous tank of the chamber (10) for loading the sluices. After the control unit signal from the previous hopper loading sensor, the conveyor stops and after filling the working area, the sensor signaling its loading to the optimum level, the inlet gas is pumped into the lock chamber by a device (17), hermetically sealed and 10) the latch. The volume of the previous container is intended to prevent the current portion of rubber-containing waste from entering the lock loading chamber (10) without causing it to overflow. After the lock loading chamber (10) is filled, the shut-off valve between the loading lock chamber (10) and the previous tank is hermetically sealed, the shutter is opened in the reactor working area (9), the hydraulic cylinder expels the rubber-containing waste dose in the reactor working area (9). returns to the starting position. At the same time, inert gas is pumped into the lock loading chamber (10) at a pressure slightly above the reactor working area (9) to prevent air entering the reactor. The activated burners (6 ') heat up the heat supply chamber (8). The rubber-containing waste that enters the reactor's working area heats up at the expense of indirect heating of the heat-supply chamber (8). At the same time, at the expense of operation of the burner (6) located in the core of the reactor (13), the rubber-containing waste is actively heated to a temperature of 400 ° C to 500 ° C. Temperature control is provided by temperature sensors located above the reactor core (13) and controlling the unit so that the temperature within the range of 0.5 to 2 inside the inner chamber of the heat transfer chamber (13) does not exceed 430 ° C. By controlling the operation of the burner (6 ') operating in the reactor core (13), the pyrolysis temperature, which occurs in the core (13) and partially in the working zone (9), is controlled. In addition, the rubber-containing waste in the reactor is mixed with a device (15) according to an algorithm that ensures its uniform heating.

The operation of the exhaust fan in the pyrolysis gas outlet conduit (14) results in reduced pressure for easier and faster venting of the pyrolysis gases from the reactor core (13) and from the lower part of the reactor operating zone (9) to minimize secondary pyrolysis gas causes a reduction in the liquid fraction and an increase in the level of undesirable impurities in the pyrolysis gas. The burners (6 ') which heat the heat-supply chamber (8) and the reactor core (13) operate on pyrolysis gas which has passed through a separation and purification system. The air mixture supplied to the inlet of the gas burner (6 ') is enriched with oxygen from 40 to 45% of the contents of the mixture for the qualitative and complete combustion of the pyrolysis gas in the burner. The control of the pressure and air mixture of the pyrolysis gas in the busbars, as well as the relationship between the amount of pyrolysis gas supplied to the burner and the air mixture is controlled by the control unit. A solid fraction consisting of a carbonaceous feedstock, hereinafter referred to as semi-coke, and metallic cord waste, accumulates at the base of the core (13). At certain intervals in the control unit, the hydraulic cylinders open the airtight latch of the lock unloading chamber (3) to separate the solid recycled fraction from the unprocessed feedstock. Prior to opening the shut-off valve of the lock discharge chamber (3), the device (17) injects inert gas under pressure slightly above the reactor pressure to prevent atmospheric air from entering the reactor. In the unloading chamber of the locks (3), the control unit controls the pressure and inflation. The solid residue from the pyrolysis process enters the damping unit from the lock discharge chamber (3). The shutter-discharge chamber (3) hermetically closes the shutter and actuates the gear auger in the damping unit, which supplies a certain amount of water and inert gas to the heat exchange process from the hot solid sediment to the water vapor and inert gas. With a slight delay after closing the damper, the gas-vapor mixture is evacuated from the damping unit in the lock discharge chamber (3). The gas-vapor mixture is discharged to an irrigation column for condensation of steam and separation of soot sludge. Contaminated runoff is discharged to a sedimentation basin, where soot deposits are deposited. The water is then passed back through the heat exchanger to the irrigation column via a closed loop. The solid sediment transported by the auger to the extinguishing unit passes through a separating sluice, which is hermetically sealed by a latch that operates in accordance with the latch of the latch unloading chamber (3) and opens only in the closed position of the latch of the latch unloading chamber (3). for separation. The operation of the dampers, the on and off of the irrigation column fan, the amount of water and inert gas fed to the quench unit are monitored by the control unit. It also controls the overload and the start and stop of the motor-gear unit (16), which turns the auger screw.

The pyrolysis gases flowing through the outlet conduit (14) pass into a cyclone, where the soot particles are pre-separated from the pyrolysis gases, then in the catalytic unit, where the pre-catalytic cracking reaction takes place. At the same time, the liquid and soot fractions are collected and discharged into separate tanks, from which the soot mass returns to the reactor working area via the loading (sluice) chamber, while the liquid fraction containing the fuel oil and diesel particles is discharged into a separate vessel. The pyrolysis gas then passes through the droplet separator into the freezer, where it is cooled with water, which runs in a closed loop. Liquid fractions containing diesel particulates and a small amount of water leave the drip trap and freezer in a separate container, from where the liquid fraction enters the soot and moisture trap, and are then pumped through a fine cleaning filter to the warehouse. After the pyrolysis of the freezing chamber, the gases pass into the rectification column through an outlet conduit at its lower end. The rectification column has at least two (preferably three) compartments interconnected to allow pyrolysis gas to flow through the top of the column. Each of the compartments is filled to about half with an acid-resistant ceramic irregular filling. At the top of the rectification column is a spray device for spraying compartments containing the liquid fuel fraction. The volume and pressure of the spray liquid is calculated by the control unit for process optimization purposes. The liquid fraction obtained in the rectification column is passed through a conduit located at the bottom of the column, which then enters a separate vessel from where the liquid fraction enters the soot and moisture separator, and is then pumped through a fine purification filter to the storage. The pyrolysis gases produced at the exit of the rectification column pass through a short pipe in the upper part of the rectification column to the pressure from which they are led to a separator for soot particles, liquid fraction residues and water to be removed from the gas. The tailings are collected in a special tank from where they pass back into the reactor working area through the loading (sluice) chamber (10). The purified gas is discharged through a compressor into a separate vessel at a pressure of about 3 bar, from which the stream of purified pyrolysis gas is split. Part of the gas is supplied to the burner (6) operating in the reactor core, part of the gas is directed to the burner (6 ') operating in the heat supply chamber (8) and the remainder of the gas to a separate combustion unit.

Oxygen is produced in the inert gas generation unit as a by-product. The inert gas generated by the generating unit is directed to a rubber (waste) loading chamber (10), a pyrolysis solid product (lock) discharge chamber (3) to an inert gas injection device (17) and to a pre-treatment unit. The inert gas enters the pre-purification unit from two locations: the combustion unit and the heat pipe short circuit (11). In the pre-purification unit, the gas is passed through a solution of lime, mixed with atmospheric air in a ratio of 1:10, and then the gas mixture is fed to a plasma catalytic purification unit for purification of harmful organic compounds: phenols, furans, benzenes, benzopyrenes, dioxins. The purification rate of the plasma catalytic purification unit reaches 90-95% of the incoming mixture, after which the purified air mixture is discharged through the tube into the environment. Such a treatment method meets the strictest environmental standards in terms of environmental impact.

Thus, the present invention makes it possible to significantly improve the efficiency of the recycling plant for automotive tires and other rubber-containing waste, to optimize the pyrolysis process, to increase the separation of liquid fractions and reduce their contamination with soot and ash, and to increase the environmental safety of gaseous products. increase the operational safety of the equipment.

Claims (8)

Claims 1. Equipment for the recycling of automotive tires and other rubber-containing waste, comprising a reactor with a sealed pyrolysis chamber, a device for feeding rubber-containing waste, 5 devices for discharging solid pyrolysis products, a system for heating rubber-containing wastes to a pyrolysis temperature in the form of a combustion chamber for solid pyrolysis products with an external rod and at least one burner having an open outlet in the combustion chamber for separating and purifying the liquid and gaseous products; system with system parts pyrolysis gaseous 10 for feeding products into a rubber-containing waste heating system, characterized in that the upper part of the pyrolysis chamber formed by two coaxially positioned tubes - internal and external - with openings in the side surfaces of both tubes, which are connected by gas discharge tubes so that the space between the outer tube forming the heat transfer chamber is separated from the space formed by the outer surface of the outer tube, The inner surface of the 15 discharge tubes and the inner surface of the inner tube forming the reactor working area, while the rubber-containing waste preheating system is further provided with a rubber-containing preheating system comprising a heat transfer chamber with burners located in its lower part. 20th Apparatus according to claim 1, characterized in that the heat transfer chamber in the lower part is provided with two burners disposed tangentially to the diameter of the inner tube at opposite points and having vectors facing each other. 25th The device according to claim 2, characterized in that the burners installed in the heat transfer chamber are located at a height of 0.5-2 inches from the upper limit of the active zone to the inner diameter of the heat transfer chamber. Device according to any one of claims 1 to 3, characterized in that the reactor A working area is equipped with a device for mixing and moving rubber waste. The device according to claim 4, characterized in that the device for mixing and transferring rubber-containing waste is designed in the form of a screw having a blade diameter to reactor working area inner diameter of 0.3-0.9: 1, preferably 0, 50.7: 1. Device according to claim 4 or 5, characterized in that the device is rubber For mixing and moving waste containing 5, the lower part is located within the inner diameter of the heat transfer chamber at a distance of 0.5-1.5 from the upper limit of the core. Apparatus according to any one of claims 1 to 6, characterized in that the loading chamber for the rubber-containing waste and the discharge of solid pyrolysis products The chamber 10 is equipped with devices for pumping inert gas to prevent atmospheric air from entering the reactor during loading of rubber-containing waste or during discharge of solid pyrolysis products.