RU2715125C1 - Method of recycling wastes in form of crushed metal cord from mechanical processing of tires and device for its implementation - Google Patents

Abstract

FIELD: heat power engineering.

SUBSTANCE: invention relates to heat engineering, in particular to utilization of wastes obtained as a result of mechanical processing of tires, by thermal treatment of said wastes with separation into components. Waste recycling device comprises a combustion chamber, a gas burner, a volatile substance discharge pipe, a collection of inert materials, combustion chamber is equipped with loading hopper, gate valve with winch for opening and closing gate valve, fan with pipeline for additional air supply to combustion chamber, bottom of combustion chamber is made in the form of tilting shutters, and collector of inert materials in the form of tray, between pan and bottom of combustion chamber there installed are vibrating sieve, in pipe for ejection of volatile materials fan of exhauster is installed.

EFFECT: invention enables to select optimum, economically efficient operating mode of unit with cyclic supply of solid fuel due to removal of solid fuel combustion products formed in preliminary heat treatment chamber by gas discharge pipe, which form on its inner walls a resinous mass, thereby reducing its volume.

2 cl, 1 dwg

Description

The invention relates to a power system and ecology, in terms of the disposal of waste resulting from the mechanical processing of tires, by the method of heat treatment of these waste products with separation into components.

Known technical solutions for the mechanical processing of worn tires with metal cord, in which the tires are crushed in stages, the resulting pieces are fractionated and subjected to magnetic separation and are reflected in a number of patents: (US patent No. 4113186, cl. 24-24-24, published. 1978).

The known method of "Recycling used tires." Collection of scientific works, M., TsNIITEneftekhim. 1982, pp. 89-92. During the mechanical processing of worn tires, the side rings are removed, cut into pieces, crushed in stages, followed by fractionation, namely, pieces are crushed using a hammer mill and rolling to extract components of recycled tires.

A known method of processing worn tires (see application RU 97105251A, B29B17 / 00, B29B17 / 02, publ. 04/10/1999), including grinding, separation of textile and metal cord, fractionation of the resulting crushed vulcanizate, preparation of dispersed vulcanizable on its basis the composition by mixing with a vulcanizing agent and a plasticizer and subsequent processing of the resulting composition by pressing, characterized in that the tire without a bead ring and cut in half along the generatrix is crushed under normal conditions There are three stages: in the first and second stages on roll-type grinders equipped with cutter sets with a distance between cutters of 50-100 mm, the second stage grinder is equipped with a calibrating grate with holes 10-40 mm in diameter, and the third stage is fine grinding - carried out in an extrusion type apparatus under conditions of shear deformations sufficient to open the textile and metal cord without additional grinding, which is then separated by separation, and the crushed vulcanizate, after fractionation sieve on a sieve with a mesh size of 1-5 mm, is directed to the preparation of a dispersed vulcanizable composition, which is carried out in the form of a vortex layer in an apparatus with a mixing rotor blade type, with a rotor speed of 300-1000 rpm, the degree of filling of the mixing chamber 2-20 % for 7-60 s with a ratio of components in the mixture.

The closest technical solution is the method and line for the processing of worn tires (application RU 2005102538 A, B29B17 / 00, B29K21 / 00, publ. 07/10/2006), in which the tires are crushed in cutting devices to obtain rubber crumb with its subsequent fractionation , subjected to magnetic separation to extract the metal cord, partially textile cord is removed, characterized in that the tires are pressurized from the inside and from the top, then in this state they are informed of rotation and fed to cutting devices, where at the stage of double grinding in one pass of the cutting heads, rotating simultaneously in the same direction, opposite the direction of rotation of the tires, a mixture of rubber crumb with metal and textile cord is obtained, which is taken by means of an air suction pump, fed through a cyclone to a magnetic conveyor, after which the metal cord is removed by the method magnetic separation.

The disadvantage is that during the mechanical processing of worn-out tires in the final stage of the technological process, finely dispersed wastes of crushed metal cord remain, consisting of twisted metal wire (10-15 mm long), not separated from textile wire and rubber residues. Due to the impossibility of separation of the components included in these wastes, the problem arises of their disposal. Tire recyclers try to dispose of them in various ways: burial in the ground, illegal removal of waste to landfills, etc. Which negatively affects the environmental situation of nearby settlements.

The closest technical solution is a device for burning solid fuel in a pulsating flow (patent RU No. 2539414 C2, F23C15 / 00, published January 20, 2015), comprising an ignition chamber, a chamber for preliminary thermal preparation of fuel, a cover for a chamber for preliminary thermal preparation of fuel, an air duct, a resonator tube consisting of two parts (upper and lower) and adjoined to the ignition chamber, forming an annular gap between its upper and lower parts, a mesh turbulator consisting of several components, a grate, nogosoplovuyu diffusion burner, a collection of solid waste, a collection of inert material. The device is equipped with a gas exhaust pipe, the upper cut of which is located in the preliminary heat treatment chamber of fuel at a distance of 2-3 diameters of this pipe from the lower part of the cover of the preliminary heat treatment chamber of fuel, the other end is located in the lower part of the resonator tube and an automatic system for controlling the temperature of thermal decomposition of rubber is introduced , with a temperature sensor of the temperature control system, one end of which is attached to the ignition chamber, and the other end is opposite the air a gadfly with the possibility of connecting and regulating its bore, and the duct is made in the form of an aerodynamic valve with a variable bore, ensuring that the gas temperature in the ignition chamber and in the preliminary heat preparation chamber is maintained at a given temperature in the automatic mode and thermal decomposition of waste rubber products with the possibility of light emission fractions for further combustion, and in the inert material collection there is a system for reducing the inert temperature material, which is formed as a group of nozzles disposed symmetrically of the diameter of the collection of inert material, and nozzles installed in an amount determined by the volume of cooled inert material.

The disadvantage of this solution is that in the above device the exhaust pipe passes through the entire combustion chamber from the bottom up to the receiving hopper, and this does not allow loading and even distribution of the above waste from the mechanical processing of tires on the combustion chamber, making it impossible to move them after firing to vibrating screen, with subsequent separation of the metal from inert materials.

An object of the invention is to provide a device and method for the disposal of waste from the mechanical processing of tires by separating the components included in their composition by heat treatment (firing) with a view to their further use in regenerative plants, scrap processing enterprises, metallurgical industry and other sectors of the national economy.

The essence of the invention lies in the fact that the method of disposal of waste, in the form of crushed metal cord from the mechanical processing of tires, including magnetic separation, while the metal cord with the remains of rubber and textile is fired, passed through a vibrating screen, freeing from ash and coke residues - soot and metal oxides , and after magnetic separation is packetized.

The essence of the invention also lies in the fact that the device for waste disposal comprising a combustion chamber, gas burner, pipes for the emission of volatile substances, a collection of inert materials, characterized in that the combustion chamber is equipped with a loading hopper, a slide gate valve with a winch for opening and closing the slide gate, a fan with a pipeline for additional air supply, the bottom of the combustion chamber is made in the form of tilting flaps, and the collection of inert materials in the form of a pallet, between the pallet and the bottom to action shaker combustion installed in the pipe for discharging volatile materials set exhauster fan.

The technical result consists in the fact that the proposed device for processing waste (crushed metal cord) allows you to choose the optimal, cost-effective mode of operation of the unit with a cyclic supply of solid fuel due to removal through the exhaust pipe formed in the preliminary heat treatment chamber of the fuel of solid fuel combustion products that form a resinous mass on its inner walls, thereby reducing its volume. The output of gaseous products of combustion is environmentally friendly due to the design of the device for burning solid fuel in a pulsating flow, and packages from scrap metal cord of tires subjected to heat treatment can increase the bulk density of scrap in the loading containers of steelmaking units.

The invention is illustrated in the drawing.

The device is a kiln, consisting of: a loading (receiving) hopper 1, for receiving a metered portion of waste (crushed fine metal cord interspersed with textile fiber and rubber residues), a slide gate 2 opening (lifting) the inlet opening to the combustion chamber 3 for receiving waste , and closing the opening (lowering) after the portion of waste enters the combustion chamber 3. The slide gate 2 is actuated (raising, lowering) by means of an electric winch 4. The portioned mixture of waste enters on the overturning flaps of the bottom 5 of the combustion chamber 3, and with the help of a gas burner 6, the inert materials (textiles, rubber) included in this mixture are ignited. The resulting volatiles from the combustion process are removed to the atmosphere using the fan of the smoke exhaust fan 7 and pipe 8. Using the fan 9, for a better combustion process, an additional air supply is made to the combustion chamber 3. After the end of the firing process using tilting flaps of the bottom 5, the heat-treated material is fed to an electric vibrating screen 10, where, by vibration, the screening (separation) of the burnt inert materials from the metal wires of the metal cord occurs. Screened inert materials enter the inert tray 11.

Waste provided to the laboratory (crushed metal cord of tires) for chemical composition studies is a mixture consisting of:

1) brass steel wires mainly made of copper, zinc and iron, containing impurities of manganese, cobalt and silicon. The composition of the steel cord wire is consistent with the composition of high-carbon steel (st 60-st70), which makes it possible to determine the temperature for tempering metal equal to 450-500 degrees. C. Brass wire to provide the necessary bond strength of the metal cord with rubber.

2) rubber inclusions (rubber) - an elastic polymer material obtained by coagulation (coagulation, thickening) of latex rubber plants (natural rubber) or by polymerization of various monomers (synthetic rubbers).

3) a polymer thread, which is a polymer containing polyamide fragments. The structure of the thread is consistent with the structure of capron or nylon.

As a result of the experiments carried out in laboratory conditions, the quantitative composition of the components after waste firing was revealed:

- pure metal - 77-82%;

- ash - 11-14%;

- volatile substances - 7-9%

Waste, consisting of a finely divided crushed mixture of metal cord, after the last stage of the mechanical processing of car tires, with the inclusion of textile and rubber residues in the metal wires of the metal cord, is loaded into the receiving hopper 1 with the dosed batch prepared in advance with the slide gate 2 open. The dosed portion of the mixture depends on the selected volume of the combustion chamber 3. The purpose of the dosed supply of the mixture is that it becomes necessary to observe the burning time of the mixture for its heat treatment, using an automatic temperature control system, with a temperature sensor of the temperature control system. After loading a metered amount of the mixture, the slide gate 2 closes the inlet of the combustion chamber 3 with a winch 4, and the mixture enters the tilting flaps of the bottom 5 of the combustion chamber 3. The loaded mixture is ignited with a gas burner 6. After the rubber and textiles entering are ignited in the mixture, the gas burner 6 is turned off and the combustion process occurs independently. The combustion temperature of inert materials (textiles and rubber) included in the waste mixture makes it possible for a certain time to temper the metal cord included in this mixture. The volatile compounds formed during the combustion process are removed from the combustion chamber 3 by means of a smoke exhaust fan 7 through an exhaust pipe 8. For the purpose of high-quality combustion, an additional air supply by fan 9 (compressor) to the combustion chamber 3 is used.

The firing process takes place in the combustion chamber 3 in the air (air supply) with a temperature of up to 500 ° C, and then without air supply. In order to accelerate the combustion of rubber and textiles, we carry out the first firing period in an oxidizing environment with excess air using a fan (compressor) 9. When the temperature reaches 500 ° C, the gas burner 6 is turned off, the air supply to the combustion chamber 3 is stopped, creating a reducing atmosphere.

A firing temperature of less than 500 ° C is impractical, since the percentage of residual rubber will be high, and the complete metal tempering process does not occur. At a firing temperature above 700 ° C, a process of increasing oxidation of the metal and burning out of the carbon that is part of the metal wire occurs, which helps to reduce the weight of the wire, which will be used for commercial purposes in the metallurgical industry. At the proposed temperature of 500 ° C, the oxidation process is minimized. In this case, only tarry and volatile substances predominantly burn, and carbon is mainly retained. As a result of this heat treatment, followed by tempering, the metal acquires plastic properties.

After the end of the process of firing the waste mixture, the annealed mixture, using the tilting flaps of the bottom 5 of the combustion chamber 3, enters the vibrating screen 10, where the soot is screened from the metal cord. Soot is sieved into a pallet 11, from where it is transported to the destination for further sale. The remaining mixture on a vibrating screen 10 is separated using an electromagnetic washer. The annealed mixture can also be passed through the rollers in order to clean the ash surface of the metal from the coke residue, then magnetically separated using an electromagnet, and packetized into wire bags by pressing wire, which can be used as a metal charge for smelting steel.

Metal cord wire without heat treatment is almost impossible to compress into packages for use in metallurgy. After heat treatment (tempering), with the acquisition of the plastic properties of the metal, there is a real possibility of packaging this steel cord.

Thus, packages of scrap metal cord tires, subjected to heat treatment, can increase the bulk density of scrap in the loading containers of steelmaking units.

    Solid inert ash-coke (soot) wastes resulting from firing are used in various industries. Unburned elements burn out in the exhaust pipe. As a result, after the whole process, the emission of harmful volatile substances into the atmosphere is reduced.

The ability to compress metal cord wire after baking (tempering) into packets of packages was tested empirically on a pressing machine in LLC “Vtutagmet”, Taganrog.

Claims (2)

1. The method of disposal of waste in the form of crushed metal cord from the mechanical processing of tires, including magnetic separation, characterized in that the metal cord with the remains of rubber and textile is fired, passed through a vibrating screen, freeing from ash and coke residues - soot and metal oxides, and after magnetic separation pack. 2. A device for waste disposal, including a combustion chamber, a gas burner, a pipe for emitting volatile substances, a collection of inert materials, characterized in that the combustion chamber is equipped with a loading hopper, a slide gate valve with a winch for opening and closing the slide gate valve, a fan with a pipe for additional air supply to the combustion chamber, the bottom of the combustion chamber is made in the form of tilting flaps, and the collection of inert materials in the form of a pallet, between the pallet and the bottom of the combustion chamber are installed quit, a smoke exhaust fan is installed in the pipe for the release of volatile materials.

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