WO2018097756A1

WO2018097756A1 - Device for processing scrap rubber

Info

Publication number: WO2018097756A1
Application number: PCT/RU2017/000831
Authority: WO
Inventors: Алексей Сергеевич ГРАДОВ; Евгений Сергеевич СУСЕКОВ; Сергей Павлович СУСЕКОВ
Original assignee: Общество С Ограниченной Ответственностью "Научно-Производственное Объединение Инноватех"
Priority date: 2016-11-23
Filing date: 2017-11-07
Publication date: 2018-05-31
Also published as: RU2632837C1

Abstract

A device for processing scrap rubber, comprising a heating chamber with a reactor provided with screw conveyors and a superheater; a fuel combustion chamber; and a condenser. The reactor is provided with a steam chamber, and the superheater consists of two elements, each of which is in the form of three parallel pipes located at the corners of an equilateral triangle and connected in sequence by three collectors. A strip is wound in a spiral in the form of a rib on the pipes, forming a screw conveyor. A first collector is mounted in the steam chamber and is connected thereto. A second and third collector are mounted in the reactor, and the outlet of the third collector is connected to the reactor. The strips of one screw conveyor contact via the rib with the pipes of another screw conveyor during rotation. The fuel combustion chamber is in the form of two flame tubes with burners at the inlet, said flame tubes being mounted along the axes of the screw conveyors and being connected by their outlets to the heating chamber. In the lower part of the reactor, a perforated tube with a plugged inlet is disposed between the screw conveyors, wherein an outlet of said perforated tube is connected to an inlet of the condenser, and a gas outlet of the condenser is connected to the flame tubes.

Description

DEVICE FOR PROCESSING RUBBER WASTE

FIELD OF TECHNOLOGY

The invention relates to waste processing technology and can be applied in the rubber, chemical industry, fuel and energy complex, as well as in housing and communal services for obtaining fuel and raw materials.

BACKGROUND OF THE INVENTION

A known method and device for the pyrolysis of tire material (US Patent JYS 6736940B2, IPC F 23G 5/12, published May 18, 2004).

The device comprises a reactor for pyrolysis and obtaining a hydrocarbon-containing gas stream and carbon-containing solid material. The gas stream exit from the pyrolysis reactor is connected to a separator, which is equipped with an oil atomization system, and the atomization system is connected to an oil cooler and ensures that part of the cooled oil is returned back to the separator to create an oil cloud in which contact washing and condensation of part of the gas stream takes place in the form oils.

The non-condensable gas outlet from the separator is connected to the screw press and the reactor combustion system, in which the non-condensable gas is burned to provide heat to the reactor.

The outlet of the reactor via carbon-containing solid material is connected to the screw press, the pressure of which, due to the part of the non-condensable gas introduced into it, is higher than in the reactor, which prevents air from entering the pyrolysis reactor when unloading the solid material.

The disadvantages of this device are:

1. Incomplete extraction of the liquid fraction (oil) from the gas stream, as a result of which a part of valuable liquid products is lost (burned in the form of gas);

2. The low quality of the carbon-containing material, due to the high content of volatile hydrocarbons that the material absorbs from the non-condensable gas supplied to the screw press, with the help of which the carbon-containing material is removed from the reactor; 3. The high energy intensity of the process, due to the need for additional processing of (thermal) carbon-containing solid material to remove volatile hydrocarbons.

A pyrolysis furnace is known (RF Patent jN 2441053, IPC F23G5 / 027, С10В 53/00, published January 27, 2012).

The furnace contains a hopper, a screw press, a heat chamber with pyrolysis gas burners, where a flow cutter is located at an angle to the direction of movement of the raw materials inside the housing of the screw mechanism, and above this screw there are more than one counter-movement along the movement of raw materials, pyrolysis screw mechanisms with their flow shutoffs, and the drive to each screw mechanism, as a rule, from one motor with a reducer, and the upper screw mechanisms have pipes attached to them to remove pyrolysis gas for useful use Bani and operation of the burners of the heat chamber, and the lower screw feed mechanism has holes for the steam to heat the chamber and heat chamber has on the side walls and the ceiling of the water pipes for boiler useful heat from the burners.

The disadvantages of this furnace are:

1. Incomplete extraction of the liquid fraction (oil) from the gas stream, as a result of which a part of valuable liquid products is lost (burned in the heat chamber burners), and high emissions of harmful substances into the environment are formed due to the inability to realize complete combustion in the heat chamber burners high resin pyrolysis gases.

2. The low quality of solid pyrolysis products due to the presence of residual hydrocarbons (volatile products) that cannot be separated out during the drying process, and therefore, additional heat treatment of these products at a high temperature of about 800 ° C is necessary.

3. The high energy intensity of the process, due to thermal losses in the process, as well as the need to increase the temperature in the furnace to 800 ° C.

A device is known for processing carbon materials using steam thermolysis technology (US Patent Application No. ° 2016/0083657 A1, publication date 03.24.2016). The design of this device includes a special loading hopper used to load ground carbonaceous waste into the reactor. The design of this device also includes: burner; a box into which combustion products enter, separated by a special device for exhaust gas suction and processed in a gas scrubber; a steam generator supplying steam to a superheater used to heat the steam inside the reactor to a temperature of 200-700 ° C; a reactor outlet used to vent steam and gaseous products formed in the reactor into a condenser connected to a separator; storage tank into which waste water enters after condensation; devices used to supply this water to the burner.

The device is equipped with special mechanisms for transferring non-condensed gases obtained after condensation of vapor- and gaseous products formed inside the reactor during steam thermolysis to the burner.

The disadvantages of this device are:

1. Incomplete extraction of the liquid fraction from the gaseous products of thermolysis of worn tires, as a result of which part of the valuable component of the light fraction together with the waste water enters the storage tank.

2. The low quality of the solid products of the pyrolysis of worn tires due to the presence of residual hydrocarbons that cannot be separated during thermolysis in the reactor, and therefore, additional heat treatment of these products at a high temperature of about 600 - 800 ° C is necessary. 3. High energy intensity of the process due to large heat losses during the thermolysis of tires in the reactor, as well as heat losses during the heat treatment of waste water in the burner.

Closest to the alleged invention is the method and device adopted by us for the prototype of the steam-thermal processing of rubber waste (Patent of the Republic of Belarus N ° 13279, IPC C08J 11/00, C10B53 / 07, publication 2010.06.30).

The device includes a heating chamber, in which a reactor is placed, made in the form of two equal parts, enclosed in a casing, placed in a vertical plane one above the other and connected in series for the spillage of waste from the upper to the lower part, each of which is equipped with a screw and a superheater in the form of a coil wound along the length of the casing - a pipe whose inlet is connected to the steam generator and the outlet is connected to the casing at the inlet of the upper part of the reactor, the heating chamber from the waste loading side is connected to the output of the fuel combustion chamber, and is connected to a steam generator by its output, the upper part of the reactor is connected by a pipe to the waste loading screw equipped with a hopper with a lock gate, and by means of a pipeline and to the three capacitors connected in series, the outlet of combustible gas from the third condenser is connected to the fuel combustion chamber, and the lower part of the reactor is connected by a pipe to the discharge hopper with a water lock gate, to which an discharge screw is connected with its input, the output of which is connected to the input of the drum dryer, which at the inlet, by means of a pipeline, it is connected to the outlet of combustion products from the steam generator, and at the outlet, it is connected in series to the screw for unloading solid products and the gas treatment filter of products Chimney connected.

The disadvantages of this device are:

1. Incomplete extraction of worn tires with gaseous pyrolysis products by means of condensers, as a result of which a part of the valuable component of the light fraction is lost (burned in the combustion chamber), as well as contamination of the liquid fraction with fine dust, which is formed as a result of grinding solid products during screw operation and removed from the reactor to the condensation system with a stream of gaseous decomposition products.

2. The low quality of the solid pyrolysis products of used tires due to the presence of residual hydrocarbons (volatile products) that cannot be separated out during the drying process, and therefore, additional heat treatment of these products at a high temperature of about 600-800 ° C is necessary.

3. High energy intensity of the process due to large heat losses during tire pyrolysis in the reactor, as well as heat losses in the capacitors (heat is removed with cooling water).

SUMMARY OF THE INVENTION The objective of the proposed invention is to improve the quality of the resulting products from rubber waste, as well as reducing energy costs for the processing process.

The problem is solved in that in a device for processing rubber waste containing a heating chamber in which a reactor is provided, equipped with screws and a superheater, a fuel combustion chamber, a condenser according to the invention, the reactor is equipped with a steam chamber, and the superheater consists of two identical elements, each of which is made in the form of three straight pipes placed at the corners of an equilateral triangle and connected in series using three collectors, and flax is wound on the pipes in a spiral a, forming a screw, the first collector is installed in the steam chamber and connected to it, and the second and third collectors are installed in the reactor, and the output of the third collector is connected to the reactor, the screws are installed in the reactor so that the tapes of one screw contact the tubes of the other during rotation a screw, and the fuel combustion chamber is made in the form of two heat pipes with burners at the inlet, installed along the axes of the screws and connected to the heating chamber by their exit, and a perforated tube is installed between the screws in the lower part along the entire length of the reactor a pipe with a muffled input, the output of which is connected to the input of the condenser, and the gas outlet from the condenser is connected to the heat pipes.

The supply of the reactor with a steam chamber allows using water vapor (the temperature of the water vapor supplied to the steam chamber approximately 100 ° C) to cool the rotation unit from overheating to high temperature. In this zone, when the burners are operating, the maximum temperature is reached, and therefore, without cooling, the entire assembly and collectors will overheat and fail. It should be noted that the heat of cooling is useful because water vapor is additionally heated before entering the superheater.

The implementation of the superheater in the form of three straight pipes placed at the corners of an equilateral triangle, connected in series with the help of three collectors, and winding onto the pipes in a spiral in the form of an edge of a tape forming a screw provides (in comparison with ordinary screws with a central pipe on which the tape is wound ) strength with a small weight, which is important, since the superheater in the reactor is heated to a temperature of at least 400 ° C. In this case, the radiation from the flame tube to the surface of the waste does not overlap, and when the superheater tube rotates, a convective motion of the vapor-gas medium is created, as a result of which the heat transfer by convection from the flame tube to the waste is intensified, which reduces the time of their processing and, as a result, reduces fuel consumption on the waste recycling process.

A superheater in the form of straight pipes allows you to overheat the water vapor that enters from the steam chamber into the first collector, and then the steam enters the second manifold, flows through the pipes connected in series and leaves the third manifold at high temperature to the reactor.

The screws in the reactor rotate towards each other, as a result of which the rubber waste in the form of chips is intensively mixed, and thus the heat transfer from the walls of the heating chamber to the rubber waste is intensified. The augers in the reactor are installed so that the auger strips extend almost over the entire rib height, which, when the augers rotate, prevents chips from sticking to the auger belt, clog the auger with chips and stop the chips from moving through the reactor from inlet to outlet, i.e. such installation of screws in the reactor prevents equipment (reactor) failure due to clogging of the screws with chips. In other words, such a screw installation provides mutual cleaning of each screw from sticking chips, which, when heated, first soften to form a viscous and sticky mass.

The implementation of the fuel combustion chamber in the form of flame tubes with burners at the inlet ensures the complete combustion of non-condensable gases that are supplied from the condenser to the flame tube. This is due to the fact that the flame tube has a significantly longer length than the length of the combustion chamber of a conventional combustion chamber for burning fuel. In a flame tube, not only does the residence time of the gas in the high temperature zone increase, but the gas flow itself is very turbulent, resulting in complete combustion of non-condensable gas. In this case, the burner, which is installed at the entrance to the flame tube, provides not only the combustion of the fuel supplied to it, but also the ignition of a mixture of non-condensable gases and air, which is supplied to flame tube, through channels and gates with adjustable cross-section for air passage, installed at the inlet of the pipe. These gates allow you to set the ratio of air and non-condensable gas necessary for complete combustion.

The installation of flame tubes along the axes of the screws in the reactor allows to reduce energy consumption (in comparison with obtaining a coolant for heating the reactor in an external furnace) by eliminating heat losses. This ensures intense heat transfer to the waste (chips) by radiation from the surface of the flame tubes. The heat pipes installed in this way are as close as possible to the chips that move in the reactor as a result of the rotation of the screws, which reduces the amount of thermal radiation absorbed by the gas medium of the reactor and increases the intensity of heat transfer directly to the chips. The installation of flame tubes along the screw axes ensures the transfer of heat by radiation and convection to the superheater pipes, as a result of which the water vapor that flows through the pipes overheats to a temperature of 500 - 600 ° C, and for this, the length of three pipes connected in series with collectors is sufficient. If the ary pipes are placed differently, for example above the screws, the heat transfer to the pipes will decrease significantly, which means that there will be a need to increase the length of the pipes to ensure that the water vapor overheats to a predetermined temperature. An increase in the length of the tubes will cause the reactor to become cluttered and block the radiation flux from the flame tubes directly to the chips in the reactor, which will lead to an increase in the required time for the complete thermolysis of the chips, i.e. decrease in reactor productivity and, as a result, an increase in energy costs for the entire process of processing rubber waste.

The installation of a perforated pipe in the lower part of the reactor along its entire length ensures the removal of thermolysis gases from the reactor and the reduction of entrainment of small carbon particles from the reactor with a stream of exhaust gases. The decrease in the entrainment of small particles of carbon dust from the reactor is due to the fact that the thermolysis gases on the way to the perforated pipe pass through a layer of chips, which acts as a filter and traps carbon dust on its own surface. This is important, since the rotation of the screws leads to the inevitable grinding of the carbon residue with the formation of including small micron particles of carbon, which enter the pipelines and the condensation system with the flow of exhaust gases, are deposited in the pipelines and the condenser, as a result of which the cross section of the pipelines becomes clogged, their hydraulic resistance increases, and the energy costs of pumping thermolysis gases from the reactor to the condensation system increase . With sufficient reactor operating time, complete clogging of pipelines and reactor failure can occur. Getting into the condensation system, small particles of carbon dust are deposited on the heat exchange surface, which increases thermal resistance, reduces the performance of the condenser.

Connecting the condenser output to the flame tubes allows the non-condensable gas to be fed into the flame tube to burn it and to obtain the thermal energy necessary for the operation of the reactor.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1, 2, 3 shows a General view and details of a device for processing rubber waste.

The device contains a drive 1 connected to the hopper 2, valves 3 and 4 for crushed rubber waste 5; reactor 6; an engine 7 connected to the gear 8, which is engaged with the gear 9 connected to the first screw 10, and also engaged with the gear of the second screw; capacity 11 connected through a tap - regulator 12 to the burners 13; flame tubes 14 connected via a pipe 15 to the heating chamber 16; a smoke exhauster 17 connected to a chimney 18; a steam generator 19 with a crane 20 connected to the steam chamber 21; a first collector 22, a superheater 23, a second collector 24, a third collector 25, an opening for steam 26; a hole for steam 27 connected to the reactor 6; two-channel measuring device 28; temperature sensor 29; high temperature seals 30, 31, 32, 33; a perforated pipe 34 with a tap 35 connected by a compressor 36 to a condenser 37; cooling tower 38; temperature sensor 39; separator 40; a water reservoir 41 connected to the filter 42; liquid hydrocarbon storage device 43; crane 44; output for solid residue 45 connected to the rotary dispenser 46; storage device carbon residue 47; crane 48; gates 49 connected separately to each flame tube.

According to the invention, the device operates as follows.

From the drive 1 to the hopper 2 with the closed gates 3 and 4 serves crushed rubber waste 5 in the form of chips. After filling the hopper 2, open the shutter 3 and the waste from the hopper 2 wake up and linger on the shutter 4. After that, close the shutter 3, open the shutter 4 and the waste wake up in the reactor 6. Then the shutter 4 is closed. At the same time, with the help of the engine 7, the gear 8 is put into rotation, which engages with the gear 9, which is connected to the first screw 10, and which engages with the gear of the second screw. This connection of the gears during rotation of the gear 8 leads to the rotation of the screws towards each other. In this case, the waste is transported from loading to unloading. Screws rotating towards each other intensively mix the waste and move it, as a result of which the heat transfer to the waste intensifies (increases).

The time of movement of waste through the reactor is controlled by changing the speed of engine 7. Simultaneously with the beginning of the process of moving waste from the tank 11 through the valve-regulator 12, the burners 13 (one burner is shown in Fig. 1) are supplied with fuel and burned, and the combustion products enter flame tubes 14. Flowing through the flame tubes 14, the fuel combustion products heat the reactor and exit through the pipe 15 connecting both flame tubes to the heating chamber 16. Flowing through the heating chamber 16, the combustion products additionally heat the reactor, and cooled.

Using a smoke exhauster 17, the combustion products cooled to a temperature of 200 - 250 ° C are removed from the heating chamber 16 to the chimney 18. This makes it possible to use the heat of the combustion products that exit the flame tubes at high temperatures (500 - 600 ° C), as for compensation for heat loss from the reactor through its surface, and to maintain high temperature in the reactor. At the same time, fuel consumption is reduced due to the full use of the heat of the combustion products and the release of thermal energy into the environment is prevented, i.e. Increases the energy efficiency of the used tire recycling process. Saturated water vapor is supplied from the steam generator 19 through the faucet 20 to the steam chamber 21, which is common to two ara pipes. Providing the reactor with a steam chamber 21 allows water vapor (the temperature of the water vapor supplied to the steam chamber 21 to be approximately 100 ° C) to cool the rotation assembly including the first collector 22 and second collector 24 from overheating to high temperature. In this zone, when the burners 13 are operating, the maximum temperature is reached and, therefore, without cooling, the collectors will overheat and fail.

From the steam chamber 21, through the first collector 22, water vapor enters the superheater 23 of each screw and flows through the pipes of the superheater connected in series with the collectors 24 and 25. Water vapor from the steam chamber 21 through the steam hole 26 enters the first manifold 22, and then first enters the first pipe of the superheater 23, passes through this pipe to the third collector 25, where it passes into another pipe and flows through it in the opposite direction, returns into the second collector 24 and passes into the third superheater pipe, flows through this pipe and through the steam hole 27 in the third manifold 25 enters the reactor 6. When moving through the pipes, the water vapor overheats to a temperature of 500 - 600 ° C as a result of convective heat exchange with the surface of the flame tubes, as well as due to the heat flux by radiation from the flame tubes having a high temperature, of the order of 600 - 650 ° C. Moreover, due to the rotation of the superheaters around the flame tubes, the convective heat transfer to the superheater tubes, as well as to the rubber waste, is intensified.

The superheat temperature of the steam is controlled by the readings of a two-channel measuring device 28.

Thus, with superheated water vapor, heat is directly introduced into the reactor 6 in the feed region of the initial rubber waste having a temperature close to ambient temperature (the waste fed to the reactor has not yet been warmed up).

The supply of superheated water vapor to this region (reactor zone) provides a high temperature difference between superheated steam up to 500 ° C and cold waste with a temperature of about 30 - 40 ° C. BUT this (high temperature difference) provides high heat fluxes from steam to the waste by convective transfer of heat energy, as a result of which the heating of the waste is accelerated and the time of its processing is reduced.

Rubber waste moves through the reactor 6 and is heated as a result of contact with the hot walls of the reactor, as well as by convective heat exchange with the steam supplied to the reactor, by radiation from the flame tubes and convective heat exchange with the surface of the flame tubes.

The placement of the flame tubes along the axes of each superheater makes it possible to bring the flame tubes closer to the surface of the rubber waste, which improves heat transfer not only by radiation, but also by convection. Since there is water vapor and hydrocarbon vapors in the reactor that absorb thermal radiation, to reduce the magnitude of this absorption, it is necessary to reduce the distance from the flame tubes to the surface of the rubber waste. At a large distance from the flame tubes to the waste surface, a significant part (depending on the distance that the thermal radiation travels) of the thermal radiation will be absorbed by the gas-vapor mixture (a mixture of water vapor and hydrocarbon vapor), as a result of which the gas-vapor mixture will be heated to a high temperature, which will lead to thermal decomposition of part of the hydrocarbons and the formation of soot, i.e. the loss of valuable hydrocarbons, as well as to increase the output of heat energy with a gas-vapor mixture of high temperature to the condensation system and the need to increase the capacity of the condensation system to remove heat energy, as a result of which heat losses increase and heat energy costs for the waste processing process increase.

In the process of heating rubber waste in the reactor 6 to a temperature of 300 ° C, the thermolysis of rubber waste begins to proceed with the release of gaseous products and solid carbon residue. The temperature in the reactor 6 is controlled by the temperature sensor 29 and controlled by changing the amount of fuel burned in the burners 13. The gaseous waste decomposition products are mixed with water vapor, as a result of which a gas-vapor mixture is formed in the reactor 6, and the pressure in the reactor rises above atmospheric . Moreover, to exclude the release of combined-cycle products high-temperature seals 30, 31, 32, 33 are installed from the reactor 6 into the environment and ensuring the rotation of the screws 10. Combined-cycle products through a perforated pipe 34 and a crane 35 using a compressor

36 is removed from the reactor 6 to the capacitor 37.

As a result of the movement of waste through the reactor under the influence of screws, the solid carbon residue is crushed to form finely dispersed carbon dust that enters the reactor. The removal of the vapor-gas mixture from the reactor without cleaning the vapor-gas mixture from dust leads to the removal of carbon dust into the pipelines and the condensation system, as a result of which the pipelines and the condensation system become clogged with carbon dust. The flow area of pipelines is reduced and the pressure in the reactor is increased. Clogging of the condensation system with carbon dust leads to a decrease in heat transfer (the dust layer on the surface of the condensation system plays the role of a thermal insulator) and the system fails. Placing the perforated pipe 34 in the lower part of the reactor between the screws can reduce the carbon dust removal from the reactor. This is because the vapor-gas mixture is taken from the reactor through perforations (openings in the pipe) from the bottom of the reactor, where the vapor-gas mixture is filtered by a layer of waste, which leads to sedimentation of carbon dust on the pieces of waste.

The vapor-gas products discharged from the reactor 6 to the condenser 37 as a result of heat exchange with cooling water pumped through the condenser casing from the cooling tower 38 are cooled to the condensation temperature of water vapor, which is monitored by the temperature sensor 39.

As a result of cooling combined-cycle products, water vapor and part of the hydrocarbon vapors condense to form a condensate consisting of water and liquid hydrocarbons. This condensate is from a condenser

37 is fed to a separator 40 and separated into water and liquid hydrocarbons. Water from the separator 40 is fed into the reservoir 41, from which through the filter 42, the water is returned to the steam generator 19 to obtain working water vapor.

Liquid hydrocarbons from the separator 40 are fed to the accumulator 43, from which a portion of the liquid hydrocarbons in the right amount through the valve 44 served in the steam generator 19 and burned, and the energy used to produce working water vapor.

The solid carbon residue through outlet 45 by means of a rotary dispenser 46 is removed from the reactor 6 and fed to the accumulator 47, where it is cooled to ambient temperature by exposure to the accumulator.

Non-condensable hydrocarbon vapors from the condenser 37 are fed through the faucet 48 to the flame tubes, and through the valves 49 installed on each flame tube, air is supplied simultaneously with the non-condensable gases, regulating its amount by the degree of opening of the gate. The air in the chimneys is sucked in through the gates, because the exhaust fan 17 works and creates a vacuum in the chimneys. As a result of mixing air and non-condensable gases, a combustible mixture is formed, which is ignited by the flame of the burners and burns. The combustion of non-condensable gases allows you to get additional energy to heat the reactor and reduce the fuel consumption supplied to the burner. This allows you to increase the energy efficiency of the processing process and prevent the release of non-condensable gases into the environment.

DEVICE EXAMPLES

The invention is illustrated by the following examples.

Example 1

From the drive 1 to the hopper 2 with the shutters 3 and 4 closed, crushed rubber waste 5 is fed in the form of chips with a flow rate of 1000 k / h. To do this, 100 kg of waste are portioned into the hopper 2, the shutter 3 is opened, and the waste from the hopper 2 wakes up and lingers on the shutter 4. After that, the shutter 3 is closed, the shutter 4 is opened, and the waste is woken up in the reactor 6. Then, the shutter 4 is closed. Thus, the frequency of loading portions is 10 times per hour. At the same time, with the help of the engine 7, gear 8 is rotated at a speed of 10 rpm, which engages with gear 9, which is connected to the first screw 10, and which engages with the gear of the second screw. This connection of the gears during rotation of the gear 8 leads to the rotation of the screws towards each other at a speed of 10 rpm As a result, the waste is transported from loading to unloading within 15 minutes. This time spent by the waste in the reactor is necessary for their complete thermal decomposition. Screws rotating towards each other intensively mix the waste and move it, as a result of which the heat transfer to the waste intensifies (increases).

The time of movement of waste through the reactor is controlled by changing the engine speed 7 and set to 10 rpm. Simultaneously with the beginning of the process of moving waste from the tank 11 through the faucet-regulator 12, fuel is supplied to the burner 13 (Fig. 1 shows one burner) and burned. Fuel is supplied to each burner with a flow rate of 40 kg / h, which, with a specific heat of combustion of 40,000 kJ / kg of fuel, provides a burner power of 440 kW, i.e. the total thermal power supplied to the reactor 6, with the operation of two burners is 880 kW. It is this capacity that is necessary, taking into account the reactor efficiency of 40%, for processing 1000 kg / h of rubber waste.

The combustion products resulting from the combustion of 40 kg / h of fuel, with a flow rate of 720 kg / h and at a temperature of T = 900 ° C, enter each flame tube 14. Thus, the combustion products with a total flow rate of 1420 kg / h enter two flame tubes. . Flowing through the heat pipes 14, the combustion products of the fuel heat the reactor and exit through the pipe 15 connecting both heat pipes to the heating chamber 16. Flowing through the heating chamber 16, the combustion products additionally heat the reactor and cool themselves.

Using a smoke exhauster 17, the combustion products cooled to a temperature of 200 - 250 ° C are removed from the heating chamber 16 to the chimney 18. This makes it possible to use the heat of the combustion products that exit the flame tubes at high temperatures (500 - 600 ° C), as for compensation for heat loss from the reactor through its surface, and to maintain high temperature in the reactor. At the same time, fuel consumption is reduced due to the full use of the heat of the combustion products and the release of thermal energy into the environment is prevented, i.e. Increases the energy efficiency of the used tire recycling process.

When cooling the combustion products in the heating chamber, the following amount of heat is released:

Q = C _P x G „.c. x (T _G T ₂ ) = \, \ 56kJ / kg ° C x 1420kg / 3600s x (600 ^o C-200 ^o Q = kJ / s = kWp, (1) where Q is the amount of heat transferred to the reactor when the combustion products are cooled, kJ / s;

G „.c. - consumption of combustion products, 1420 kg / h;

Ср - specific heat of combustion products, 1,156 kJ / kg ° С;

T] the temperature of the combustion products at the entrance to the heating chamber, 600 ° C;

Ϊ2 - temperature of the combustion products at the outlet of the heating chamber, 200 ° C. Moreover, it is assumed that the average heat capacity of the combustion products in the range from 200 ° C to 600 ° C is C /> = 0.5 (C ₂₀₀ + C ₆₀₀₀ ) = 0.5 (1.097 + 1.214) = 1.156 kJ / kg ° C (see table 6. Physical properties of flue gases. V.P. Isachenko, V.A. Osipova, A.S. Sukomel Heat Transfer.- M .: Energoatomizdat, 1981, p. 404).

The beneficial use of heat in the amount of 182 kW allows you to save 16.4 kg / h of liquid fuel.

Saturated water vapor is supplied from the steam generator 19 through the valve 20 to the steam chamber 21, which is common for two flame tubes, at a flow rate of 300 kg / h at a temperature of 110 ° C.

From the steam chamber 21, through the first collector 22, water vapor with a flow rate of 150 kg / h enters the superheater 23 of each screw and flows through the superheater pipes connected in series with the second collector 24 and the third collector 25. Water vapor from the steam chamber 21 through the steam hole 26 enters the manifold 22, and then from the first collector 22 it enters the second manifold 24 into the first pipe of the superheater 23, passes through this pipe to the third collector 25, where it passes into another pipe and flows through in the opposite direction, returns to the second collector 24 and passes into the third superheater pipe, flows through this pipe and through the steam hole 27 in the third collector 25 enters the reactor 6. When moving through the pipes, the water vapor overheats to temperature T = 500 ° C as a result of convective heat exchange with the surface of the heat pipes, as well as due to the heat flux from the heat pipes from heat pipes. Moreover, due to the rotation of the superheaters around the flame tubes, the convective heat transfer to the superheater tubes, as well as to the rubber waste, is intensified. The superheat temperature of the steam is controlled by the readings of a two-channel measuring device 28. The superheat temperature of the water vapor is controlled both by the steam flow rate (increase the flow rate with increasing steam temperature and lower the flow rate when the temperature decreases), and the amount of fuel burned in the burners 13.

The supply of superheated water vapor to this region (reactor zone) provides a high temperature difference between superheated steam up to 500 ° C and cold waste with a temperature of about 30 - 40 ° C. And this (high temperature difference) provides high heat fluxes from steam to the waste by convective transfer of heat energy, as a result of which the heating of the waste is accelerated and the time of its processing is reduced.

Rubber waste moves through the reactor 6 and is heated as a result of contact with the hot walls of the reactor, as well as by convective heat exchange with the steam supplied to the reactor, by radiation from the flame tubes and convective heat exchange from the surface of the flame tubes.

In the process of heating rubber waste in the reactor 6 to a temperature of 300 ° C, the thermolysis of rubber waste begins to proceed with the release of gaseous products and solid carbon residue. The temperature in the reactor 6 is controlled by the readings of the temperature sensor 29 and is controlled by changing the amount of fuel burned in the burners 13.

In our case, the thermolysis of rubber waste generates 40% of gaseous products in the form of hydrocarbon vapors (400 kg / h) and 60% of the carbon residue (600 kg / h).

Gaseous waste decomposition products are mixed with water vapor, as a result of which a steam-gas mixture is formed in reactor 6 in an amount of 400 kg / h + 300 kg / h = 700 kg / h and the pressure in the reactor rises above atmospheric. Moreover, to exclude the release of combined-cycle products from the reactor 6 into the environment and ensure the rotation of the screws 10 high-temperature seals 30, 31, 32, 33 are installed. Combined-cycle products through a perforated pipe 34 and valve 35 using a compressor

36 with a flow rate of 700 kg / h are removed from the reactor 6 to the condenser 37.

The vapor-gas products removed from the reactor 6 to the condenser 37 as a result of heat exchange with cooling water pumped through the casing of the condenser from the cooling tower 38 are cooled to the condensation temperature of water vapor T = 100 ° C, which is controlled by the readings of the temperature sensor 39.

When cooling 700 kg / h of combined-cycle products from T = 300 ° C to T =

100 ° C, it is necessary to remove the following amount of heat in the condenser 37: Q _K = Cf. _n . x G _nM . x (/ l - T _2P ) + FM _K = 2kJ / kg ° C x 700kg / 3600s x (300 ° C -

100 °) + W kJ / kg x 600 / sg / ZbOOs = bOvkJ / s = 306 kW, (2)

where QK is the heat of cooling and condensation;

Wed.p. - specific heat of combined-cycle products, 2 kJ / kg ° C;

Gn.n. - consumption of combined-cycle products, 700 kg / h;

Yaf is the average heat of condensation of water vapor and gas-vapor products,

1370 kJ / kg;

Тш - temperature of products at the inlet to the condenser, 300 ° С;

Tgp is the condensation temperature, 100 ° C.

Mk - the number of condensing products, 600 kg / h.

As a result of cooling combined-cycle products, water vapor in the amount of 300 kg / h and part of the hydrocarbon vapor in the amount of 300 kg / h are condensed with the formation of condensate in the amount of 300 kg / h + 300 kg / h = 600 kg / h, consisting of water and liquid hydrocarbons .

Thus, the thermal power of the cooling tower 38 should be at least 310 kW for cooling and condensation of combined-cycle products.

This condensate from the condenser 37 with a flow rate of 600 kg / h is fed into the separator 40 and is separated into water and liquid hydrocarbons. Water from the separator 40 with a flow rate of 300 kg / h is fed into the reservoir 41, from which through the filter 42 the water is returned to the steam generator 19 to obtain working water vapor.

Liquid hydrocarbons from the separator 40 with a flow rate of 300 kg / h are fed to the accumulator 43, from which part of the liquid hydrocarbons with a flow rate of 30 kg / h are supplied to the steam generator 19 through a valve 44 and burned, and the energy is used to produce working water vapor. The solid carbon residue through outlet 45 using a rotary dispenser 46 with a flow rate of 600 kg / h is removed from the reactor 6 and fed to the accumulator 47, where it is cooled to ambient temperature by exposure to the accumulator.

Non-condensing hydrocarbon vapors from condenser 37 through a tap

48 with a flow rate of 100 kg / h are fed into the flame tubes 14, and through the gates 49 installed on each flame tube simultaneously with the supply of non-condensable gases, air is supplied with a flow rate of 1600 kg / h, adjusting its amount by the degree of opening of the gate. The air in the chimneys is sucked in through the gates, because the exhaust fan 17 works and creates a vacuum in the chimneys. As a result of mixing air and non-condensable gases, a combustible mixture is formed, which is ignited by the flame of the burners and burns.

The combustion of non-condensable gases allows you to get additional energy to heat the reactor and reduce the fuel consumption supplied to the burner. The amount of this energy is as follows:

Qr = qr x Mr = \ 5000kJ / kg x 100kg / 3600s = PkJ / s = 417kW, (3)

where Qr is the amount of heat released during the combustion of non-condensable gases;

qr - specific heat of combustion of gases, 15000 kJ / kg;

Mr - the amount of gas burned, 100 kg / h.

Combustion of non-condensable gases saves 38 kg / h of liquid fuel. Therefore, the amount of fuel supplied from the tank 11 to the burners 13 is reduced from 80 kg / h to 42 kg / h, i.e. instead of 40 kg / h, 21 kg / h are fed to each burner.

Example 2

From the drive 1 to the hopper 2 with the closed gates 3 and 4 serves crushed rubber waste 5 in the form of chips with a flow rate of 500 f / h. To do this, 50 kg of waste are portioned into the bunker 2, the shutter 3 is opened, and the waste from the bunker 2 wakes up and lingers on the shutter 4. After that, the shutter 3 is closed, the shutter 4 is opened, and the waste is woken up in reactor 6. Then, the shutter 4 is closed. Thus, the portion loading frequency is 10 times per hour. At the same time, with the help of the engine 7, the gear 8 is rotated at a speed of 5 rpm, which engages with the gear 9, which is connected to the first screw 10, and which engages with the gear of the second screw. This connection of the gears during rotation of the gear 8 leads to the rotation of the screws towards each other at a speed of 5 rpm As a result, the waste is transported from loading to unloading within 15 minutes. Such a residence time of the waste in the reactor is necessary for their complete thermal decomposition. Screws rotating towards each other intensively mix the waste and move it, as a result of which the heat transfer to the waste intensifies (increases).

The time of movement of waste through the reactor is controlled by changing the engine speed 7 and set to 5 rpm. Simultaneously with the beginning of the process of moving waste from the tank 11 through the faucet-regulator 12, fuel is supplied to the burner 13 (Fig. 1 shows one burner) and burned. Fuel is supplied to each burner with a flow rate of 20 kg / h, which at a specific heat of combustion of 40,000 kJ / kg of fuel provides a power of each burner of 220 kW, i.e. the total thermal power supplied to the reactor 6, with the operation of two burners is 440 kW. It is this capacity that is necessary, taking into account the reactor efficiency of 40%, for processing 500 kg / h of rubber waste.

The combustion products resulting from the combustion of 20 kg / h of fuel, with a flow rate of 360 kg / h and at a temperature of T = 850 ° C, enter each flame tube 14. Thus, the combustion products with a total flow rate of 720 kg / h enter two flame tubes. . Flowing through the heat pipes 14, the combustion products of the fuel heat the reactor and exit through the pipe 15 connecting both heat pipes to the heating chamber 16. Flowing through the heating chamber 16, the combustion products additionally heat the reactor and cool themselves. By means of a smoke exhauster 17, the combustion products cooled to a temperature of 250 ° C are discharged from the heating chamber 16 to the chimney 18. This makes it possible to use the heat of the combustion products that exit the flame tubes into the heating chamber at a high temperature (500 ° C), as for compensation heat loss from the reactor through its surface, and to maintain high temperature in the reactor. This reduces fuel consumption due to the full use of the heat of the combustion products and the release of thermal energy into the environment is prevented, i.e. Increases the energy efficiency of the used tire recycling process.

Q = C _P x G „.c. x (Τι-Τ ₂ ) = \, YkJ / kg ° C x 720kg / 3600s x (500 ° C-250 ° C) = YkJ / s = YkW, (4)

where Q is the amount of heat transferred to the reactor when the combustion products are cooled, kJ / s;

G _n .c. - consumption of combustion products, 720 kg / h;

Ср - specific heat of combustion products, 1.14 kJ / kg ° С;

T] is the temperature of the combustion products at the entrance to the heating chamber, 500 ° C;

Tg is the temperature of the combustion products at the outlet of the heating chamber, 250 ° C.

Moreover, it is assumed that the average heat capacity of the combustion products in the range from 250 ° C to 500 ° C is equal to C _P = 0.5 (C ₂₅ o + C ₅₀ o) = 0.5 (1.10 + 1.18) = 1 , 14 kJ / kg ° C (see table 6. Physical properties of flue gases. V. P. Isachenko,

V.A. Osipova, A.S. Sukomel Heat Transfer, - M: Energoatomizdat, 1981, p.

404).

The beneficial use of heat in the amount of 57 kW saves 5.1 kg / h of liquid fuel.

Saturated water vapor is supplied from the steam generator 19 through the faucet 20 to the steam chamber 21, which is common for two flame tubes, at a flow rate of 150 kg / h at a temperature of 100 ° C.

From the steam chamber 21, through the first collector 22, water with a flow rate of 75 kg / h enters the second collector 24, and then into the superheater 23 of each screw and flows through the pipes of the superheater, which are connected using the second collector 24 and the third collector 25 in series.

Water vapor from the steam chamber 21 through the steam hole 26 enters the first collector 22, from which it enters the second collector 24, into the first pipe of the superheater 23, passes through this pipe to the collector, the third 25, where it passes into another pipe and flows through it into in the opposite direction, returns to the second collector 24 and passes into the third superheater pipe, flows through this pipe and through the steam hole 27 to the third collector 25 enters the reactor 6. When moving through the pipes, the water vapor overheats to a temperature of T = 600 ° C as a result of convective heat exchange with the surface of the flame tubes, and also due to the heat flux from the flame tubes having a high temperature. Moreover, due to the rotation of the superheaters around the flame tubes, the convective heat transfer to the superheater tubes, as well as to the rubber waste, is intensified.

The superheat temperature of the steam is controlled by the readings of a two-channel measuring device 28. The superheat temperature of the water vapor is controlled both by the steam flow rate (increase the flow rate with increasing steam temperature and lower the flow rate when the temperature decreases), and the amount of fuel burned in the burners 13.

Thus, with superheated steam directly into the reactor

6 introduce heat into the feed area of the original rubber waste having a temperature close to ambient temperature (the waste fed to the reactor has not yet warmed up).

The supply of superheated water vapor to this region (reactor zone) provides a high temperature difference between superheated steam up to 600 ° С and cold waste with a temperature of about 30 - 40 ° С. And this (high temperature difference) provides high heat fluxes from steam to the waste by convective transfer of heat energy, as a result of which the heating of the waste is accelerated and the time of its processing is reduced.

Rubber waste moves through the reactor 6 and is heated by contact with the hot walls of the reactor, as well as by convective heat exchange with the steam supplied to the reactor, by radiation from the flame tubes and convective heat exchange from the surface of the flame tubes.

In the process of heating rubber waste in the reactor 6 to a temperature of 400 ° C, thermolysis of rubber waste begins to proceed with the release of gaseous products and solid carbon residue. The temperature in the reactor 6 is controlled by the readings of the temperature sensor 29 and is controlled by changing the amount of fuel burned in the burners 13. In our case, the thermolysis of rubber waste generates 50% of gaseous products in the form of hydrocarbon vapors (250 kg / h) and 50% of the carbon residue (250 kg / h).

Gaseous waste decomposition products are mixed with water vapor, as a result of which a gas-vapor mixture in the amount of 250 kg / h + 150 kg / h = 400 kg / h is formed in the reactor 6 and the pressure in the reactor rises above atmospheric. Moreover, to prevent the escape of combined-cycle products from the reactor 6 into the environment and to ensure the rotation of the screws 10, high-temperature seals 30, 31, 32, 33 are installed. Combined-cycle products through a perforated pipe 34 and valve 35 using a compressor 36 with a flow rate of 400 kg / h are removed from reactor 6 to capacitor 37.

When cooling 400 kg / h of combined-cycle products from T = 400 ° C to T = 100 ° C, it is necessary to remove the following amount of heat in the condenser 37: QK = Срм-х G _n . _n x (T _1P - T _2P ) + R-ΦΜΚ = 2kJ / kg ° C x 400kg / 3600s x (400 ° C - 100 ° Q + \ b10kJ / kg x ZOOkg / ZbOOc = 1 \ kJ / s = 114kW, ( 5)

where QK is the heat of cooling and condensation;

Wed p. - specific heat of combined-cycle products, 2 kJ / kg ° C;

Gn.n. - consumption of combined-cycle products, 400 kg / h;

R _< p is the average heat of condensation of water vapor and gas-vapor products, 1370 kJ / kg;

Тш - temperature of products at the inlet to the condenser, 400 ° С;

Tgp is the condensation temperature, 100 ° C.

As a result of cooling combined-cycle products, water vapor in the amount of 150 kg / h and some hydrocarbon vapors in the amount of 200 kg / h are condensed with the formation of condensate in the amount of 150 kg / h + 200 kg / h = 350 kg / h, consisting of water and liquid hydrocarbons .

Thus, the thermal power of the cooling tower 38 should be at least 114 kW for cooling and condensation of combined-cycle products. This condensate from the condenser 37 with a flow rate of 350 kg / h is fed into the separator 40 and is separated into water and liquid hydrocarbons. Water from the separator 40 with a flow rate of 150 kg / h is fed into the reservoir 41, from which through the filter 42 the water is returned to the steam generator 19 to obtain working water vapor.

Liquid hydrocarbons from the separator 40 with a flow rate of 200 kg / h are fed to the accumulator 43, from which part of the liquid hydrocarbons with a flow rate of 15 kg / h are fed through a valve 44 to the steam generator 19 and burned, and the energy is used to produce working water vapor.

The solid carbon residue through outlet 45 by means of a rotary dispenser 46 with a flow rate of 250 kg / h is withdrawn from the reactor 6 and fed to the accumulator 47, where it is cooled to ambient temperature by holding in the accumulator.

Non-condensing hydrocarbon vapors from condenser 37 are supplied through the faucet 48 with a flow rate of 50 kg / h to the flame tubes, and through the valves 49 installed on each flame tube, air is supplied at a flow rate of 800 kg / h simultaneously with the non-condensing gases, adjusting its amount by the degree of opening gateway. The air in the chimneys is sucked in through the gates, because the exhaust fan 17 works and creates a vacuum in the chimneys. As a result of mixing air and non-condensable gases, a combustible mixture is formed, which is ignited by the flame of the burners and burns.

Q _r = qr Mr = 15000kJ / kg x 50kg / 3600s = 20 $ kJ / s = 2 W, (6)

qr is the specific heat of combustion of gases, 15,000 kJ / kg;

Mr - the amount of gas burned, 50 kg / h.

The burning of 50 kg / h of non-condensable gases saves liquid fuel in an amount of 19 kg / h. Therefore, the amount of fuel supplied from the tank 11 to the burner 13 is reduced from 40 kg / h to 22 kg / h, i.e. instead of 20 kg / h, 11 kg / h are fed to each burner.

INDUSTRIAL APPLICABILITY

The claimed device for processing rubber waste differs from the known improved performance in energy costs, emissions into the environment and the quality of the resulting products.

Claims

CLAIM

A device for processing rubber waste containing a heating chamber in which a reactor is provided, equipped with screws and a superheater, a fuel combustion chamber, a condenser, characterized in that the reactor is equipped with a steam chamber, and the superheater consists of two identical elements, each of which is made in the form of three straight pipes placed at the corners of an equilateral triangle and connected in series using three collectors, and a tape forming a screw is wound around the pipes in a spiral in the form of a rib, the first collector It is installed in the steam chamber and connected to it, and the second and third collectors are installed in the reactor and the output of the third collector is connected to the reactor, the screws are installed in the reactor so that the tapes of one screw touch the edges of the pipes of the other screw during rotation, and the fuel combustion chamber is made in in the form of two flame tubes with burners at the inlet, installed along the axes of the screws and connected to the heating chamber by their exit, and in the lower part along the entire length of the reactor between the screws there is a perforated pipe with a muffled entrance, the output of which connected to the inlet of the condenser, and the gas outlet from the condenser is connected to the heat pipes.