RU2347801C1 - Hydrocarbon pyrolysis plant - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention is applicable to heat treatment facilities designed for thermal decomposition of crushed hydrocarbon materials, in particular for pyrolysis of rubber-containing materials such as crushed car tyres to obtain useful components for power engineering and construction material production. The hydrocarbon pyrolysis plant include a pyrolysis chamber with heat transfer medium supply and gas bleed ducts; a pre-heating chamber for hydrocarbon materials and a cooling chamber for solid pyrolysis residues located vertically one after the other and interconnected through gate valves; and a heating heat exchanger. The supply duct supplies heat transfer medium from the heat generator through communication with the interior space of the pyrolysis chamber and the bleed duct bleeds gas from the pyrolysis chamber and has communication with the supply duct that supplies heat transfer medium to the heating heat exchanger. This forms a closed system where pyrolysis gas is bled from the pyrolysis chamber and supplied to the chamber interior space. Furthermore the bleed duct bleeds pyrolysis gas through the cooling heat exchanger to collecting ducts for pyrolysis liquid and noncondensing pyrolysis gas.

EFFECT: more efficient hydrocarbon pyrolysis plant.

11 cl, 1 dwg

Description

The invention relates to devices for the thermal processing of crushed hydrocarbon raw materials by thermal degradation, in particular for the pyrolysis of rubber-containing materials, for example, crushed automobile tires, to obtain useful constituents used in the energy sector and in the production of building materials.

A device is known for a vertical furnace for the thermal processing of solid waste (AS USSR No. 1679140, MKI F23G 5/027, publ. 23.09.91, Bull. No. 35), containing a loading device, a unit for unloading pyrolysis products in the form of a conveyor system and a chamber pyrolysis, separated by a rectangular shaft with a perforated lid for the selection and distribution of gas-vapor products.

A known furnace for the pyrolysis of worn automobile tires and the method implemented by this device (Japanese application 58-24473, IPC C10J 3/02, publ. 05.21.83), including a vertical pyrolysis chamber, a tubular heat exchanger mounted coaxially inside the chamber, interacting with its mechanism raising and lowering, outlet pipes for the gaseous pyrolysis products, a unit for withdrawing solid pyrolysis residues, in which the tire package is located on the outside of the tubular heat exchanger.

A known furnace for the pyrolysis of hydrocarbon raw materials and the method implemented by this device (application Germany 2949983, IPC СВВ 53/00, 1981), containing the upper and lower parts interconnected using a conical detachable connection installed in the cavity of the upper part of the furnace with the formation of its side walls and the ceiling of the overall gap, the pyrolysis chamber, facing downward with an open end, pipes for supplying and removing heating gas and means for removing pyrolysis products. A disadvantage of the known devices and methods implemented in them is the high energy consumption, the complexity of the design, the complexity of loading and unloading.

Known operating furnace for the pyrolysis of car tires (RF patent No. 2078111, IPC C10B 1/4, C10G 1/10, C10B 53/08, publ. 04/27/97, Bull. No. 12), containing a pyrolysis chamber with gas extraction channels from pyrolysis chambers and coolant supply to the pyrolysis chamber jacket, means for selecting pyrolysis products, pyrolysis gas cooling device, exhaust pipe. The disadvantages of this pyrolysis method include the cyclicity of the process, which reduces the productivity of the furnace, external heat input, the effect of high temperatures only on the outer and inner diameter of the tires, the complexity of loading and unloading, and the low weight of the feedstock. Partially, these shortcomings are compensated by the lack of costs for grinding tires.

A known installation for the pyrolysis of crushed hydrocarbons (RF patent No. 2240339, IPC C10G 9/14, C10G 9/20, C10B 1/04, publ. 2004.11.20), consisting of a furnace with a furnace in the lower part, a pyrolysis chamber is installed inside the furnace in the form of a coil, with channels for taking gas from the pyrolysis chamber and supplying coolant to the jacket of the pyrolysis chamber, means for selecting pyrolysis products, a loading device in which raw materials are preheated, containers for collecting solid pyrolysis fractions, where hot pyrolysis products are cooled.

A known installation for the pyrolysis of rubber-containing wastes (RF patent No. 58533, IPC C10G 9/14, publ. November 27, 2006), including vertically and sequentially one after another and interconnected by gates, a pyrolysis chamber with channels for supplying a coolant to the jacket of the pyrolysis chamber and gas sampling from the pyrolysis chamber, the chamber for preheating the raw materials and the chamber for cooling solid pyrolysis residues, the exhaust pipe, the chamber for preheating the raw materials and the chamber for cooling pyrolysis residues in communication with the atmosphere, and The means for selecting pyrolysis products from the pyrolysis chamber is made with the possibility of forced evacuation and separation of the pyrolysis gas.

However, in the known installation, the process of heating the raw materials is not efficient enough, which reduces the productivity of the furnace, the quality of the pyrolysis products and increases energy consumption, and the emission of exhaust gases into the atmosphere worsens the environmental situation.

The technical result to which the invention is directed is to increase the productivity of the installation, improve the quality of the pyrolysis products, reduce energy costs, improve the environmental friendliness of the installation.

The technical result is achieved by the fact that in the installation for the pyrolysis of hydrocarbon feedstock, including a pyrolysis chamber with channels for supplying a coolant and gas selection from the pyrolysis chamber, a chamber for preheating the feedstock and a cooling chamber for solid pyrolysis residues located vertically and sequentially one after another and interconnected by gates , the heat exchanger of heating, new is that the channel for supplying the heat carrier from the heat exchanger is in communication with the internal volume of the pyrolysis chamber, and the sampling channel is and from the pyrolysis chamber it is in communication with the channel for supplying the heat carrier to the heat exchanger, forming a closed system for taking pyrolysis gas from the pyrolysis chamber and supplying it to its internal volume, in addition, the channel for taking pyrolysis gas through the cooling heat exchanger is communicated with the channel for collecting pyrolysis liquid and the channel for collecting non-condensable pyrolysis gas.

The coolant supply channel - pyrolysis gas to the heat exchanger is equipped with a cyclone and a fan.

The non-condensable pyrolysis gas collection channel has a normally open solenoid valve, a compressor and a pyrolysis gas collection tank, in addition, the non-condensable pyrolysis gas collection channel is connected via control flaps to the combustion air supply channel in the heating heat exchanger and to the fuel supply channel to the heating heat exchanger.

At the outlet of the channel for collecting pyrolysis liquid with an adjustable level of height, a container for collecting pyrolysis liquid is installed at the outlet of the condensing part of the pyrolysis gas.

The exhaust gas channel of the heat exchanger is in communication with the preheating chamber, a fan is installed in it, at the inlet of which a control damper is installed.

The cooling chamber for the solid pyrolysis residues has a channel for the extraction of steam generated in the cooling chamber, communicated through a heater and a regenerative cooler with a chamber for preheating the feedstock.

The cooling chamber for the solid pyrolysis residues is equipped with a stirrer.

The pyrolysis chamber and the solid residue cooling chamber have vibrators to increase the discharge intensity.

A regenerative heat generator was used as a heating heat exchanger.

The installation is equipped with a control unit and a gas flow regulator in the burner device of the regenerative heat generator, which ensure automatic maintenance of the set temperature of pyrolysis gas heating.

The installation has a loading device in the form of a bucket type conveyor.

The essence of the utility model is illustrated in the drawing, where: 1 - camera preheating of raw materials; 2 - pyrolysis chamber; 3 - a chamber for cooling solid pyrolysis residues; 4 - recuperative heat generator; 5 - loading valve; 6 - the upper shutter of the pyrolysis chamber; 7 - the lower shutter of the pyrolysis chamber; 8 - valve unloading solid pyrolysis residue; 9 - mixer chamber for cooling solid pyrolysis residues; 10 - pressure sensor of the burner device of the heat generator 4; 11 - a channel for supplying a coolant from a regenerative heat generator 4 into the pyrolysis chamber 2; 12 - channel for the selection of gas from the pyrolysis chamber 2; 13 - a channel for supplying a heat carrier to a heat generator 4; 14 - recuperative cooling heat exchanger; 15 - channel for collecting pyrolysis liquid; 16 - channel for collecting non-condensable pyrolysis gas; 17 - a cyclone; 18 - recirculation fan; 19 - electrovalve; 20 - compressor; 21 - capacity for collecting pyrolysis gas; 22 - channel for supplying air to the burner of the heat generator 4; 23 - channel for supplying fuel to the heat generator 4; 24 - capacity for collecting pyrolysis liquid; 25 - channel exhaust; 26 - suction fan; 27 - a regulating gate; 28 - channel for supplying water for cooling; 29 - water capacity; 30 - water supply pump; 31 - channel for the selection of steam from the cooling chamber 3; 32 - air heater; 33 - vibrator; 34 - control unit; 35 - gas flow regulator in the burner device; 36 - bucket type conveyor; 37 - recuperative heat recovery unit; 38 - cylinder with valve (external fuel source for heat generator 4); 39 - suction fan; 40 - temperature sensor in the channel for supplying gas to the pre-heating chamber 1; 41 - oxygen concentration sensor; 42 - temperature sensor in the channel 12 for supplying pyrolysis gas into the pyrolysis chamber; 43 - temperature sensor of the cooling chamber; 44 - fan recycling system.

The installation for the pyrolysis of hydrocarbon feedstock includes vertically and sequentially sequentially installed a pre-heating chamber for raw materials 1, a pyrolysis chamber 2 and a cooling chamber for solid pyrolysis residues 3. As a heat exchanger, a regenerative heat generator 4. The pyrolysis chamber 2 has a loading valve 5 and an upper 6 and bottom 7 shutters connecting the chambers 1, 2, 3. The cooling chamber for the solid pyrolysis residues 3 has a valve for discharging the solid pyrolysis residue 8 and is equipped with a stirrer 9. Pyrolysis chamber 2 has a channel 11 for supplying coolant from a recuperative heat generator 4, in communication with the internal volume of the pyrolysis chamber 2, and a channel 12 for taking gas from the pyrolysis chamber 2, in communication with the channel 13 for supplying coolant to the heat generator 4, forming a closed system for taking pyrolysis gas from the pyrolysis chamber 2 and filing it into its internal volume. The pyrolysis gas withdrawal channel 12 through the cooling heat exchanger 14 is in communication with the pyrolysis liquid collecting channel 15 and the non-condensable pyrolysis gas collecting channel 16. The channel 13 for supplying pyrolysis gas to the regenerative heat generator 4 is equipped with a cyclone 17 and a recirculation fan 18.

In the channel 16 for collecting non-condensable pyrolysis gas there is a normally open electrovalve 19, a compressor 20 and a container 21 for collecting pyrolysis gas, in addition, channel 16 for collecting non-condensable pyrolysis gas is communicated through control flaps with channel 22 for supplying combustion air in heat generator 4 and with channel 23 fuel supply to the heat generator 4.

In the channel 15 for collecting pyrolysis liquid with an adjustable height level at the outlet of the condensing part of the pyrolysis gas, a container 24 for collecting pyrolysis liquid is installed.

The exhaust gas channel 25 of the heat generator 4 through the recuperative heat recovery unit 37 is in communication with the pre-heating chamber 1, a suction fan 26 is installed in it, at the input of which a control flap 27 is installed.

The cooling chamber for the solid pyrolysis residues 3 has a channel 28 for supplying water for cooling from the tank 29 to the pump 30 and a channel 31 for withdrawing steam generated in the cooling chamber 3 through the air heater 32 for circulation to the tank 29. In addition, heat is supplied through the recovery system and a regenerative heat exchanger cooler 14 is sent to the preheating chamber of the raw material 1.

The pyrolysis chamber 2 and the cooling chamber for solid residues 3 have vibrators 33 to increase the discharge intensity.

Installation for the pyrolysis of hydrocarbon feeds is equipped with a control unit 34 and a gas flow regulator 35 in the burner device of the heat generator 4, providing automatic maintenance of the set heating temperature of the pyrolysis gas.

Installation for the pyrolysis of hydrocarbons has a loading device in the form of a bucket type conveyor 36.

The installation works as follows.

In the first cycles, the installation starts by connecting an external gas source 38 (propane cylinders, network gas) through the valve to the gas valve inlet of the burner of the regenerative heat generator 4. Using the conveyor 36, the required amount of crushed raw materials (tires, firewood, coal, etc.) is loaded into the chamber pre-heating 1 with the closed upper valve 6 of the pyrolysis chamber 2. Open the upper valve 6 and fill the feed from the pre-heating chamber 1 into the pyrolysis chamber 2. At the same time, the lower valve 7 of the pyrolysis chamber s 2 is closed. The upper valve 6 of the pyrolysis chamber 2 is closed, and the prescribed amount of raw material is again loaded into the preheating chamber 1 using the conveyor 36. The recirculation fan 18 of the pyrolysis gas and the exhaust fan of the combustion products 26, the fan of the heat recovery system 44 are turned on from the control unit 34. The supply valve 44 is opened. from the cylinder 38 of gaseous fuel from an external source to the gas valve of the burner of the regenerative heat generator 4. By pressing a button on the control unit 34, the burner of the regenerative heat generator is started 4. The gradual heating of the residual air begins in the voids of the pyrolysis chamber 2 not filled with raw materials and in the gas suction channels from the pyrolysis chamber, in the cyclone 17, inside the fan 18 and in the inner cavity of the heat exchanger of the regenerative heat generator 10. The heating time until the first signs of pyrolysis start appearing (≥ 180 ° C) depends on the power of the burner of the regenerative heat generator 4, on the mass of the loaded raw materials, the mass of the channel materials and, of course, on the quality of thermal insulation. From the moment the burner of the regenerative heat generator 4 begins to work, the heating of the raw materials in the preheating chamber 1 also begins. The combustion products from the exhaust pipe of the heat generator 4 pass through the channel 25 into the regenerative heat recovery unit 14 of the exhaust gases, then they enter the fan inlet 26 and then are blown into the internal cavity the pre-heating chambers 1 and passing through the voids between the raw materials give off heat to the latter and are released into the atmosphere under the hood of the suction fan 39. The temperature of the the pre-heating chamber 1 of the combustion products should not exceed 180, measured by a temperature sensor 40, supported by the amount of intake air from the atmosphere using an automatically adjustable damper 27 mounted on the tee before entering the fan 26.

The pyrolysis chamber 2, the preheating chamber 1, and the channels of movement of hot products have good thermal insulation from a material that can withstand high temperatures. When the raw material reaches a temperature of ≥180 ° C in the pyrolysis chamber 2, a gradual pyrolysis begins with the release of the pyrolysis gas into the residual air. The pressure in the system of the recirculation mixture of gas (pyrolysis and residual gas) gradually increases, and the mixture begins to be diverted through channel 12 to a regenerative cooler 14, from which through a normally open solenoid valve 19, to the inlet of the air channel 22 to the burner of the heat generator 4. Exit of the heated mixture from the lower nozzle of the regenerative cooler 14 are excluded by the height of the liquid shutter, usually equal to 100-120 mm

An oxygen concentration sensor 41 is installed on the mixture discharge line after a normally open electrovalve 19. As the output of pyrolysis gas from the feed increases, the oxygen concentration in the mixture decreases, in turn, the residual oxygen enters an exothermic reaction with the heated mass of the feed, and when the minimum oxygen concentration is reached from the sensor 41 receive a signal to close the normally open solenoid valve 19. The compressor 20 is turned on to pump the non-condensable part of the pyrolysis gas into the tank 21. When it reaches bone 21 of the gas pressure corresponding to the adopted low pressure value (250-500 mm of water column), the external gas source 38 can be turned off and pass through the system of valves and pressure reducer 35 to the burner of the heat generator 4 with pyrolysis gas.

The liquid fraction of the pyrolysis gas fills the lower cavities of the regenerative cooler 14 and when the height of the liquid fraction in this cavity is greater than the height of the liquid shutter (h), it starts to flow into the receiver of the container for collecting the pyrolysis liquid 24. The most favorable temperature measured by the temperature sensor 42, at which the highest yield of the liquid fraction is observed (52-54% of the mass of the loaded raw materials), the temperatures are 450-500 ° C. These temperature values are automatically supported by the automatic control of the burner power of the heat generator 4. The end of the complete pyrolysis of the loaded raw materials is determined by the termination of the flow of the liquid fraction through the liquid shutter of the regenerative cooler 14, on the one hand, and the disappearance of excess pressure (100-120 mm water column) in the system pyrolysis gas recirculation by pressure sensor 10. Turn off the compressor 20, sequentially the burner of the heat generator 4, the recirculation fan 18 and the exhaust fan combustion products 26.

With the lower shutter 8 of the cooling chamber 3 closed, the lower shutter 7 of the pyrolysis chamber 2 is opened and solid residues are poured into the cooling chamber 3. To achieve the best discharge, briefly turn on the electric vibrator 33 of the pyrolysis chamber 2. Close the lower shutter 7 and open the upper shutter 6 of the pyrolysis chamber 2. A preheated mass of raw material is poured from the preheating chamber 1 into the pyrolysis chamber 2. The upper shutter 6 of the pyrolysis chamber 2 is closed, the recirculation fan 18 is turned on again, p suction of the combustion products 26 and ignite the burner of the heat generator 4. The above cycle is repeated, while simultaneously pre-loading the pre-heating chamber 1 with raw materials.

In the cooling chamber 3 by a pump 30 installed in a water tank 29, small portions of water are injected through the nozzles. The generated steam is discharged through the channel 28 from the cooling chamber 3 to the heat recovery heater 32, and the resulting steam-water mixture is discharged through the channel 31 back into the container 29 and is bubbled through a certain layer of water in this container. In this case, for better cooling of the solid pyrolysis residues, the stirrer 33 of the cooling chamber 3 works. When the temperature of the solid pyrolysis residues reaches ≤150 ° C, which is detected by the temperature sensor 43, the flow of water in small portions to the cooling chamber 3 is stopped. The lower shutter 8 opens, and solid pyrolysis residues are poured into the receiving hopper and used for the next processing. In order to achieve the best possible discharge from the cooling chamber 3, the electrovibrator 33 is turned on for a short time. After the solid residues of pyrolysis are completely deposited, the lower valve 8 is closed.

In the proposed installation, the pyrolysis gas is taken from the pyrolysis chamber 2 during its formation and through the channel 12 through the cyclone 17 and the suction fan 18 is supplied to the heat exchanger of the regenerative heat generator 4, in which it is heated and sent through the channel 11 directly into the pyrolysis chamber 2. The raw material is heated from inside heated pyrolysis gas contributes to its faster decomposition, which speeds up the pyrolysis process, increases plant productivity and the quality of the products obtained. The efficiency of using the coolant approaches 85-90%. There is no emission of pyrolysis gas (LFGP) into the atmosphere (ecology) at any stage of the cycle or its flaring. The yield of non-condensable part of the pyrolysis gas is about 15% of the loaded mass. For the complete transition of the installation to pyrolysis gas, 1/3 of its inlet is enough. The rest of the pyrolysis gas (LFGP) can be used to produce steam, hot water, and generate electricity. Heated air from the heat recovery system can be used to heat utility rooms around the unit. The liquid fraction is used to produce gasoline, diesel fuel and heating oil and is of greatest commercial interest.

Thus, the proposed installation for the pyrolysis of hydrocarbon raw materials has high productivity due to the efficient heating of the raw materials, by supplying the pyrolysis gas heated in a recuperative heat generator directly inside the pyrolysis chamber, it is possible to obtain high quality pyrolysis products. The proposed installation solves pressing issues of energy and environmental conservation.

Claims (11)

1. Installation for the pyrolysis of hydrocarbon feedstock, including a pyrolysis chamber with channels for supplying coolant and gas from the pyrolysis chamber, a chamber for preheating the feedstock and a cooling chamber for solid pyrolysis residues located vertically and sequentially one after another and connected by gates, a heating heat exchanger, characterized the fact that the coolant supply channel from the heat generator is in communication with the internal volume of the pyrolysis chamber, and the gas withdrawal channel from the pyrolysis chamber is communicated with the supply channel lonositelya in the heating heat exchanger to form a closed system selection pyrolysis gas of the pyrolysis chamber and feed it into its internal volume, in addition, the channel selection pyrolysis gas through the cooling heat exchanger in communication with the collecting channel pyrolysis liquid and non-condensed pyrolysis gas collecting channel. 2. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that the supply channel of the coolant in the heat exchanger is equipped with a cyclone and a recirculation fan. 3. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that the pyrolysis gas collection channel has a normally open solenoid valve, a compressor and a pyrolysis gas collection tank, in addition, the pyrolysis gas collection channel is communicated through control valves with an air supply channel to combustion and with a fuel supply channel in a heating heat exchanger. 4. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that in the channel for collecting pyrolysis liquid with an adjustable level of height, a cyclone is installed at the outlet of the condensing part of the pyrolysis gas, and a container for collecting pyrolysis liquid is installed at its outlet. 5. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that the exhaust gas channel of the heat exchanger is in communication with the preheating chamber, a suction fan is installed in it, at the inlet of which there is a control damper. 6. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that the cooling chamber for solid pyrolysis residues has a channel for the selection of steam generated in the cooling chamber, communicated through a heater and a regenerative cooler with a chamber for preheating the raw materials. 7. Installation for the pyrolysis of hydrocarbon materials according to claim 1, characterized in that the pyrolysis chamber and the cooling chamber for solid residues have vibrators to increase the discharge intensity. 8. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that the cooling chamber for solid pyrolysis residues is equipped with a stirrer. 9. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that a regenerative heat generator is used as a heating heat exchanger. 10. Installation for the pyrolysis of hydrocarbon raw materials according to claim 1, characterized in that it is equipped with a control unit and a gas flow regulator in the burner of the heating heat exchanger, which automatically maintains the desired heating temperature of the pyrolysis gas. 11. Installation for the pyrolysis of hydrocarbons according to claim 1, characterized in that it has a loading device in the form of a bucket conveyor.