RU2841534C1 - Thermochemical conversion plant - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to thermochemical conversion of carbon-containing products. Proposed is a thermochemical conversion plant comprising a frame on which the following elements are installed: a furnace with burners and a reactor, implemented in the same housing, wherein the first outlet of the housing is connected to the connection unit by a pipeline, the second output of the housing is connected to the wet scrubber; connection unit configured to connect the reactor and the synthetic gas stabilization unit and the separation of paraffin, extruded particles and asphaltenes, unit for stabilizing synthetic gas and separating paraffin, suspended particles and asphaltenes, configured to stabilize the synthetic gas and separate paraffins, other suspended particles and asphaltenes therefrom, which first output is connected to the heat exchangers unit by the pipeline, which second and third outputs are connected to the paraffin and asphaltenes draining tank first and second inputs by pipelines, unit of heat exchangers, made in form of shell-and-tube heat exchangers with possibility of cooling and condensation of synthetic gas, which first output is connected to the synthetic gas filtration and stabilization unit, which second output is connected to the condensate drain tank input by the pipeline; synthetic gas filtration and stabilization unit, configured to remove fine inclusions, which output is connected to the gas separator by a pipeline; gas separator, made with possibility of the synthetic gas drying and fine purification, which outlet is connected to the gas burners inlet by the pipeline; tank for draining paraffin and asphaltenes, divided by a partition into two parts, one of which is configured to receive paraffin, second part is made with possibility of receiving asphaltenes; condensate drain tanks, which outputs are connected to the fuel filter by the pipeline; fuel filter made with possibility of the condensate cleaning and the cleaned condensate output to the external accumulator by means of the pipeline; wet scrubber configured to clean the flue gases coming from the reactor, wherein unit for stabilization of synthetic gas and separation of paraffin, suspended particles and asphaltenes, unit of heat exchangers, synthetic gas filtration and stabilization unit, gas separator are located on the plant upper level, and at the lower level there is a tank for products of the first and second steps of cleaning synthetic gas, a tank for draining condensate, a fuel filter, a scrubber, frame is a rectangular base configured to provide lifting and loading unit.

EFFECT: providing a compact, mobile thermochemical conversion plant.

3 cl, 4 dwg, 2 ex

Description

Field of technology to which the invention relates

The invention relates to the field of processing carbon-containing products, in particular to an installation for the thermochemical conversion of carbon-containing products.

State of the art

There are known installations for thermochemical conversion of carbon-containing products without oxygen access, they contain a reactor and a reactor heating unit. In such installations, at all stages of product conversion (raw materials and/or waste), the oxidation process and their contact with the external environment are completely excluded.

The reactor heating unit is designed to heat the reactor and maintain the operating temperature inside the reactor during the thermochemical conversion cycle.

The heating unit is a metal frame (box), covered with a metal sheet and lined from the inside with a heat-insulating layer. The box is equipped with inspection windows, a door, burner devices operating on liquid fuel and a gas mixture of hydrocarbons, a system of pressure and temperature sensors, shut-off valves, a system for supplying liquid fuel and a gas mixture of hydrocarbons to the burners, and an air supply system.

The reactor consists of a heat-insulating casing, a support frame, a rotating retort (reactor) with support rollers and a retort rotation drive. The retort is equipped with a loading door with an internal mechanism for transporting and unloading carbon residue, as well as pressure and temperature sensors.

A thermochemical conversion unit is known (RU108556 U1, published 2011.09.20), which allows to improve the activation of the processing in a low-temperature reactor. The specified technical result is achieved by the fact that in the known unit, comprising a reactor having a tubular rotating body with a receiving hopper-feeder located above the loading chamber, as well as a drive feeder and a product discharge chamber, according to the utility model, the drive feeder is made in the form of a differential hydraulically driven pusher, which has a pair of pistons telescopically installed with the possibility of interaction by means of a return spring in the area of the loading chamber, wherein the end surfaces of the pusher pistons have a ratio of 1:4, and the loading chamber is made conical, the cones of its surfaces to the mouth are selected from a ratio of 1:50, and on the side window, available in the body of the loading chamber at the inlet, a receiving hopper-feeder is installed, the bottom of which is made in the form of a sealing cover. A maximum pressure sensor or limit switch is installed in the loading chamber. The drive pusher and the drive of the sealing cover are made in the form of hydraulic cylinders.

However, the known installation is not mobile and cannot be easily transported.

A thermochemical conversion reactor is known (RU2704177C1, published 2019.10.24) The known invention relates to the field of housing and communal services and can be used for environmentally friendly processing of solid municipal waste. The reactor includes a pyrolysis chamber with a double outer wall, through the opening of which hot gas is passed for convective heating of waste for their thermochemical decomposition, and a drying chamber installed above the pyrolysis chamber, through which exhaust hot gases are passed for preliminary heating and drying of waste, the pyrolysis chamber in cross-section has the shape of an extended oval with a minimum length of the short axis for maximum heating of waste between two hot metal walls, and along the edges of the base of the loading hopper, the drying chamber and the pyrolysis chamber there are rectangular openings in which two shunt flat valves with electric drives are mounted, between which ring activators with cutting blades for loosening and crushing waste are located. The invention provides for an increase in reactor productivity.

However, the known reactor is not mobile and cannot be easily transported.

A plant for thermal destruction of predominantly municipal solid waste to obtain a carbon residue is known (RU2747898C1, published 2021.05.17). The known invention relates primarily to technologies for the disposal of predominantly municipal solid waste (MSW), including municipal garbage, as well as other types of waste similar in properties, in particular waste from the polymer, food, woodworking, and petrochemical industries. The technical result is deep complex processing of waste of various origins containing a hydrocarbon component, with the production of synthetic coal as a commercial product while simultaneously increasing the energy efficiency and productivity of the thermal destruction process. The plant comprises a sequentially connected waste preparation and grinding unit with a section for feeding ground waste into a thermolysis reactor, a multi-stage line for cleaning exhaust gaseous fractions, water purification and collecting the liquid phase and waste for disposal. The thermolysis reactor is made multi-chamber, consists of vertical steel reaction chambers of rectangular cross-section, each of which has a width of 600 - 620 mm, a length of at least 1200 mm, a height of 6000 - 7000 mm and is made with the possibility of heating along the height from the bottom up, equipped with an external lining made of refractory materials, an external two-layer lining with heat-insulating and refractory layers, a supporting metal frame. The reaction chambers are connected to each other with the possibility of ensuring their series-parallel operation, each reaction chamber is equipped with a loading feeder at the top, a gas burner device at the bottom, an unloading unit, which is connected to a block for collecting carbon residue formed during the waste thermolysis process. The unloading unit is made in the form of a unloading cone, a rotary valve-feeder and a screw conveyor-cooler, wherein the bodies of the unloading cone, rotary valve-feeder and screw conveyor-cooler are connected to each other in series, equipped with a water cooling jacket and connected to a cooling water supply device that ensures the creation of a single cooling circuit with a closed cooling water circulation cycle, wherein each screw conveyor-cooler is additionally connected to a water vapor circulation line for cooling the carbon residue by contacting it with cooling wash water, and each reaction chamber is connected to collectors of fuel gas, raw synthesis gas and flue gases.

However, the known installation is not mobile and cannot be easily transported.

A thermochemical conversion plant selected as a prototype is known (US7452392B2, published 2008-11-18). The known plant comprises a reactor for converting organic waste, such as municipal waste, wastewater, post-consumer waste and biomass, into commercially sold materials. The invention provides the following: 1. Maximum conversion of energy from organic material 2. High consumption volume of organic feedstock 3. Less pollution by gaseous products than in prior art systems 4. Solid residues for disposal are minimal and non-hazardous. The conversion is carried out by combining anaerobic gasification and pyrolysis of the original organic material and converting it into synthetic gas. Synthetic gas is a mixture of hydrocarbons (CxHy), hydrogen and carbon monoxide with small amounts of carbon dioxide and nitrogen. The essential feature of the invention is a hot driving gas, devoid of free oxygen and rich in water, which supplies all the thermal and chemical energy required for the reactions. This hot driving gas is produced by complete substoichiometric combustion of the fuel (CxHy) before it enters the reactor.

However, the known installation is not compact and mobile, it does not contain a water seal.

Disclosure of invention

In one aspect of the invention, a thermochemical conversion plant is disclosed, comprising a frame on which the following elements are mounted:

a furnace with burners and a reactor, implemented in one housing, wherein the first outlet of the housing is connected by a pipeline to the connection unit, the second outlet of the housing is connected to a wet scrubber;

a connection unit designed with the possibility of connecting the reactor and the unit for stabilizing the synthetic gas and separating paraffin, suspended particles and asphaltenes;

a synthetic gas stabilization and paraffin, suspended particles and asphaltenes separation unit designed with the possibility of stabilizing the synthetic gas and separating paraffins, other suspended particles and asphaltenes from it, the first outlet of which is connected by a pipeline to a heat exchanger unit, the second and third outlets of which are connected by pipelines to the first and second inlets of a container for draining paraffin and asphaltenes;

a heat exchanger unit made in the form of shell-and-tube heat exchangers with the ability to cool and condense synthetic gas, the first outlet of which is connected to a synthetic gas filtration and stabilization unit, the second outlet of which is connected by a pipeline to the inlet of a tank for draining condensate;

a filtration and stabilization unit for synthetic gas, designed with the ability to remove finely dispersed inclusions, the outlet of which is connected by a pipeline to a gas separator;

a gas separator designed with the ability to dry and finely purify synthetic gas, the outlet of which is connected by a pipeline to the inlet of the gas burners;

a container for draining paraffin and asphaltenes, divided by a partition into two parts, one of which is designed to receive paraffin, the second part is designed to receive asphaltenes;

containers for draining condensate, the outlets of which are connected by a pipeline to the fuel filter;

a fuel filter designed to clean the condensate and deliver the cleaned condensate to an external storage tank via a pipeline;

a wet scrubber designed to clean flue gases coming from the reactor;

moreover

a synthetic gas stabilization and paraffin, suspended particles and asphaltenes separation unit, a heat exchanger unit, a synthetic gas filtration and stabilization unit, a gas separator are located on the upper level of the unit, and a container for the products of the first and second stages of synthetic gas purification, containers for draining condensate, a fuel filter, a scrubber are installed on the lower level, the frame is a rectangular base designed to ensure lifting and loading of the unit.

In additional aspects, it is disclosed that a system for exhausting flue gases is additionally contained using an exhaust fan, the dimensions of the installation correspond to the overall dimensions of a 40-foot container.

The main task solved by the claimed invention is the creation of a compact, mobile thermochemical conversion unit.

Currently, multi-block principles of equipment assembly are used to use the processes of thermochemical conversion of carbon-containing materials. A monoblock plant in the dimensions of a sea container (40 feet), with the preservation of all the functional features of the thermochemical conversion technology, with high productivity, the possibility of using a transport platform (placement on a wheeled chassis, a railway platform), which does not require construction and installation work, has been implemented for the first time due to the fact that it is not obvious which elements need to be used, how to arrange them in an optimal way.

The essence of the invention is that the installation contains all the components necessary for its operation, installed relative to each other so as to ensure the possibility of all necessary processes and to occupy as little space as possible at a given capacity of the installation. The layout of the proposed installation allows it to be transported without disassembling, which allows it to be launched in a new location immediately after unloading without the need for additional work. It is also possible to leave the installation on the transport module (semi-trailer) and operate it in this form.

The technical result achieved by the solution is to provide a compact, mobile thermochemical conversion unit.

Brief description of the drawings

Fig. 1 shows the view of the firebox from the side and from above.

Fig.2 shows the burner.

Fig. 3 shows the reactor and furnace in section.

Fig.4 shows a diagram of the thermochemical conversion plant.

Implementation of the invention

The following describes an installation for processing a carbon-containing product by thermochemical conversion. The installation contains at least the following components:

a heat-insulated housing in which the firebox and reactor are installed;

a furnace designed with the possibility of burning fuel supplied to it to heat the reactor of the installation;

a horizontal cylindrical reactor designed to rotate around a horizontal axis, receive products and ensure their thermochemical conversion;

control elements designed to control the processing process;

synthetic gas stabilization tank, paraffin fraction drain;

asphaltene condenser;

container for draining paraffin and asphaltenes (separated by a partition);

heat exchanger – 2 pcs.;

gas filter;

gas water seal;

Synthetic gas stabilization tank;

Synthetic gas dryer;

fine fuel filter;

scrubber (wet).

other elements listed below and which are integral to the installations of the type described.

All elements of the plant are manufactured at the manufacturing plant, assembled there through assembly operations and implement a common function: the disposal of carbon-containing materials and waste.

The firebox is a metal frame (box) covered with a metal sheet and lined from the inside with a high-tech thermal insulation layer based on ceramic fiber. The box is equipped with inspection windows, a door, burners operating on liquid synthetic fuel and/or gas, a system of temperature sensors, shut-off valves, a system for supplying liquid synthetic fuel and/or gas to the burners, a low- and high-pressure air supply system. Elements not described here in detail are typical and do not relate to the essence of the solution.

The firebox is assembled at the manufacturing plant using assembly operations. The frame elements are connected to each other using welding or threaded connections. The air and fuel supply system is mounted on the body using threaded connections and welding in the designated places. The sensors are installed inside the body using quick-release fasteners. A control and monitoring panel can be installed on the body using threaded connections.

The furnace is designed to heat the reactor and maintain the temperature inside the reactor required for the thermochemical conversion process.

In one embodiment, the firebox is equipped with three “warming” liquid fuel or gas burners and two “supporting” gas burners, combined with an air supply system.

The number of burners is not significant within the framework of the declared solution and is determined mainly by the geometric dimensions of the installation, considerations of uniform heating and simplicity of design.

The entire declared installation is supplied from the manufacturer ready for use, and is a structurally and functionally unified device, all elements of which are connected by assembly operations.

The integral elements of the firebox are:

the body on which all the elements of the firebox are installed;

burners;

air supply system;

fuel supply system;

temperature sensors.

A reactor is connected to the furnace.

The reactor consists of a heat-insulating casing, a support frame, a rotating retort with four support rollers and a retort rotation drive. The retort is equipped with a loading door with an internal mechanism for transporting and unloading carbon residue, as well as pressure and temperature sensors. The heat-insulating casing (thermal casing) consists of three parts joined together by a bolted connection and lined from the inside with a heat-insulating layer based on ceramic fiber.

The reactor has a loading door, the diameter of which allows loading almost any carbon-containing product whole and in any form, without preliminary preparation (cutting and grinding).

A fully closed automatic system for unloading carbon residue from the reactor consists of a system of metal spirals and blades (inside the reactor). The movement of carbon residue occurs due to the reverse rotation of the reactor without using an additional drive for the unloading system. After the end of the thermochemical cycle, this system allows for continuous unloading of carbon residue in a dust-free manner (due to the tightness of the entire system)

The reactor's thermal jacket is insulated with a ceramic fiber-based material with high thermal insulation characteristics, low expansion during heating and rapid heat transfer during cooling.

The presence of a metered air flow supply system, with an increase in the supply of cold air under the reactor's thermal jacket, allows for a reduction in the reactor's cooling time and, accordingly, the overall operating cycle time of the rotary-type installation.

The reactor is equipped with an inert gas supply unit to prevent possible ignition of the remaining hydrocarbon gas mixture, which ensures industrial safety and increases the reliability of the plant.

The rotation of the reactor, provided by the design of the rotary unit, promotes uniformity of the thermochemical conversion process throughout the entire volume of the carbon-containing product, crushing of the carbon residue and preventing its adhesion to the internal walls of the reactor.

The support rollers under the reactor have an air cooling system to increase the reliability of the bearings and, as a result, increase the reliability of the unit, since failed bearings can lead to the reactor stopping rotating.

Uniform heating of the reactor surface, due to the use of a metered air flow from the furnace, determines an increase in its service life, high heat transfer of the reactor surface and high-quality temperature control, which increases the reliability of the installation.

The design of the reactor and furnace is calculated taking into account the safety requirements for personnel (temperature of the housing) and the lowest losses of coolant (heat transfer efficiency), both for the furnace and for the reactor.

The reactor door and its end section are also insulated with high-temperature material (ceramic fiber) to reduce heat loss.

The air supply mode into the space between the reactor vessel and the thermal insulation of the outer casing has been calculated. For intensive heat exchange between the reactor and air, the cooling air supply intensity has been set in the calculated gap between the reactor thermochemical conversion chamber vessel and the thermal insulation of the reactor outer vessel. For a given reactor length, the gap size in millimeters between the reactor and the thermal jacket has been calculated.

The installation as a whole and its parts are manufactured in accordance with the requirements of the Eurasian Economic Union (EAEU). All materials and equipment used have the appropriate passports and certificates.

The unit is equipped with sensors for monitoring the parameters of all parts. The amount of carbon-containing products loaded into the reactor is calculated taking into account the volume of gas formation during the thermochemical conversion process.

In the installation, all interconnected processes of thermochemical conversion are not associated with oxygen oxidation of the carbon-containing product. In addition, at the entire stage of the thermochemical process of carbon-containing products, their contact with the external environment is completely excluded.

The unit can be used both in the version on a wheeled chassis and installed on a flat concrete platform, including one assembled from reinforced concrete slabs. No capital structures are required to place the unit. Depending on the climatic features of the territory, it can be installed in any type of production facility, any type of hangar, production facility or workshop, the linear and height dimensions of which allow the unit to be placed.

The metal used in the production of process equipment is selected taking into account the thermochemical process occurring in the reactor and furnace. All welds and the tightness of the containers are checked by non-destructive testing methods (ultrasonic testing, pneumatic and hydraulic testing).

High reliability of the installation is ensured by the use of technologies applied in the petrochemical industry. The "lego" principle allows for quick replacement of any parts and units, which determines the high maintainability of all parts of the installation and the installation as a whole.

The currently used pyrolysis plants for processing rubber and plastic into fuel have many problems, briefly described below.

To initiate and maintain the pyrolysis process, it is necessary to heat up the reactor and maintain the temperature at the required level. For these purposes, well-known manufacturers use a special reactor heating unit - a furnace equipped with liquid fuel burners or running on solid fuel - coal, firewood. Gas burners for heating the reactor with pyrolysis gas are also located on the furnaces. Most manufacturers do not supply this unit assembled, offering the customer to independently manufacture the unit from fireclay bricks, which leads to the following problems. Firstly, the quality of the unit will be inferior to the factory version, since customers of the equipment, as a rule, are not specialists in the manufacture of specialized furnaces. Secondly, fireclay bricks are not the optimal material for a process associated with exposure to high temperatures (up to 1300 ° C) and cyclic cooling-heating (20 ° C → 1300 ° C) up to 2 times a day. With such cyclicity in the specified temperature ranges, fireclay bricks quickly deteriorate, requiring long-term and expensive repairs. Moreover, fireclay bricks have low thermal insulation characteristics, which leads to high energy costs when the firebox is heated. On the other hand, this material cools down for a long time (600 °C → 70 °C for about 8-10 hours), which leads to an increase in the working time of the pyrolysis unit. Refusal to use fireclay bricks allows for the mobility of the unit due to the fact that it becomes lighter, and the fiber insulation is more resistant to loads during transportation.

Usually, for working with pyrolysis fuel, manufacturers use liquid fuel burners equipped with a non-hermetic fuel tank with a removable lid directly on the burner body. Given the presence of light, easily flammable fractions in pyrolysis fuel, there is a high risk of fuel ignition in such a tank.

The design feature of the known furnaces is the possibility of contact of the burner flame with the reactor and furnace walls. This circumstance leads to rapid wear and fatigue of the reactor metal and collapse of the furnace lining, which reduces the reliability of the thermochemical conversion plant.

To carry out the pyrolysis reaction, well-known manufacturers use a metal vessel under pressure - a reactor. Two types of reactors are usually used: crucible (static) and rotary (rotating). Crucible-type reactors are inferior to rotary reactors in many parameters, including operational reliability.

Rotary reactors from well-known manufacturers also have a number of disadvantages. Firstly, the lining of the reactor's heat-insulating casing is made of fireclay. This material has all the disadvantages of fireclay bricks and is not an optimal material for thermal insulation of a pyrolysis reactor. Secondly, such reactors do not have thermal insulation of the reactor ends, including the reactor loading door, which leads to large heat losses, increased energy costs and the time of the pyrolysis working cycle.

A frequent problem is the rapid wear of the reactor support rollers. This occurs due to overheating of the bearings located inside the rollers, evaporation of the lubricant and failure of the entire rotation unit.

Manufacturers do not equip reactors with a system for inert gas injection into the reactor. The absence of this system dramatically reduces the safety level during operation of such a plant, since pyrolysis gas may remain in the reactor after the pyrolysis of the raw material, which may ignite when mixed with air. Thus, opening the reactor door without preliminary injection of inert gas is extremely dangerous.

The loading door of other manufacturers is usually 1200 mm. In this case, it is assumed that hydraulic devices are used to feed raw materials (tires and plastics) into the reactor, which requires additional energy and maintenance. In addition, small-diameter doors increase the time of unloading the metal cord (in the case of tire pyrolysis) and, accordingly, increase the total time of the pyrolysis cycle.

Many other manufacturers have a screw-type system for unloading carbon residue from the reactor. As a result, small residual metal rolls into dense balls, and when they get into the screw unloader, the screw jams, and the unloading system fails for an indefinite period of time. Also, other manufacturers usually place the screw inside the reactor (at the outlet), thereby exposing it to high temperatures and coking, which dramatically reduces the service life of the screw and leads to frequent breakdowns of the housing and the electric motor of the screw.

The proposed approach to heating the reactor, which excludes contact of the burner flame with the surface of the reactor and the walls of the furnace, increases the service life of the reactor and furnace and allows avoiding accidents, i.e., increases its reliability.

The furnace air supply system allows for faster heating of the reactor surface. This design solution allows for a significant increase in equipment productivity without additional wear of the construction materials, which is ensured by the fact that the air supply system prevents flame contact with furnace elements or reactor elements, i.e. while maintaining a high level of fuel combustion and, accordingly, high heating of the internal space of the installation, the internal space of the installation is protected from destruction due to contact with flame.

Active air movement inside the furnace, provided by air flows from the ejectors, promotes uniform temperature distribution throughout the volume of the installation, which also increases the reliability of its operation (conversion process).

The system of air supply to the furnace allows to significantly reduce the heating and cooling time of the reactor, and accordingly the entire working cycle as a whole, by pumping a large amount of air (air oxygen) into the furnace.

The internal thermal insulation of the firebox is made of heat-resistant (up to 1400 °C) material based on ceramic fiber. The cyclic mode of heating and cooling of the firebox does not affect the quality and durability of this material, which eliminates the need for frequent repairs and replacement of the thermal insulation layer, which reduce the economic efficiency of production and increase operating costs.

The weight of ceramic fiber lining is an order of magnitude less than that of fireclay brick or refractory concrete lining. Due to this, the loads and requirements for the furnace foundation are significantly reduced. In addition, ceramic thermal insulation has a significantly lower heat capacity compared to fireclay brick and refractory concrete, which reduces the heating and cooling time of the reactor.

To supply the coolant to the combustion chamber and heat the reactor, two types of burners are used: warming up and supporting, they can be either liquid fuel or gas. The burners can work both together and separately. Warming up and supporting burners use the following types of fuel: diesel; gas oil; synthetic fuel obtained as a result of the process of thermochemical conversion of a carbon-containing product (raw materials/waste); methane; propane-butane; gas produced as a result of the process of thermochemical conversion of carbon-containing raw materials.

In order to eliminate contact between the burner flame and the reactor surface and furnace walls, a system has been developed consisting of burners (heating and supporting), each of which is integrated into a multi-channel air flow ejector.

Uniform contactless heating of the reactor surface due to a metered air flow ensures high, uniform and controlled heat transfer, which leads to a reduction in the time of thermochemical conversion (pyrolysis) due to the stability of thermochemical processes.

The system of metered air flow into the furnace allows to significantly reduce the heating and cooling time of the reactor and, accordingly, the entire working cycle as a whole by pumping a large amount of air into the furnace.

The design of the reactor and furnace allows for the creation of a compact installation due to the horizontal arrangement of the reactor, the rotating reactor and the furnace located directly below the reactor.

Fig. 1 shows a side and top view of the firebox, where

100 – firebox body,

101 – location of gas burner installation,

102 – location of liquid fuel burner installation,

103 – ejector.

As can be seen from Fig. 1, each burner is equipped with an ejector 103, which creates air flows that prevent contact of the flame with the elements of the installation.

This design provides:

- 100% combustion of fuel due to the active supply of oxygen from the air into the combustion zone through a specially designed device - a multi-channel ejector 103 of the air flow;

- reduction of the reactor heating time (to the temperature of the beginning of the process of thermochemical conversion of the product) to no more than 3 hours and the reactor cooling time (to 90 °C) to no more than 5 hours due to the ejectors 103 of the air flow, such efficiency of operation leads to a reduction in the total time of the thermochemical conversion process compared to classical lined (heat-resistant concrete or fireclay brick) furnaces without a multi-channel ejector air flow system by more than 50%;

- extends the service life and trouble-free operation of burners;

- extends the service life and trouble-free operation of the reactor vessel;

- ensures the durability of the firebox heat-insulating coating by forming a torch from the burners using ejector 103 to eliminate direct constant contact of the burner flame with the surface of the heat-insulating coating.

The air flow ejector 103 provides the ability to control the shape of the burner flame, this function is performed by the tubular channels of the ejector 103, located at a certain angle (this angle is from 60 to 80 degrees). The air flows supplied through the ejector channels due to the inclination relative to the horizontal axis of the burners, are connected at a certain distance (preferably, this distance corresponds to the vertical projection of the central axis of the reactor) from the point of the beginning of the formation of the torch. The resulting "air bag" prevents the chaotic spread of the flame of the torch of the burners in vertical and horizontal directions. Thus, the torch of the burners is inside a dense air flow. Depending on the volume of fuel supplied to the burner, the intensity and density of the air flow of the ejector 103 can change. The described configuration scheme equally applies to both the main "warming" burners and the "supporting" heaters.

The proposed solution differs from the classic method of changing the flame size. Usually, to change the flame torch length, either the fuel supply or the power of the blower fans built into the burners is reduced. This approach reduces the thermal load on the furnace or reactor structure, but at the same time, the temperature decreases and the time of thermochemical processes increases, i.e., the plant productivity is significantly reduced. In the proposed solution, such interrelations are eliminated. The solution developed by the authors can maintain high intensity of burner operation without fear of negative impact of the burner torch on the plant elements.

The design of the ejector is shown in Fig. 2, in which

200 – cylindrical body of ejector 103 with a cylindrical hole for placing the burner in the center,

201 – inlet channel for air supply by the air supply system,

202 – outlet channels for creating an air sac.

The outlet channels 202 are placed uniformly along the perimeter of the cylindrical body 200. The number of outlet channels 202 should be from 6 to 12. The lower limit is determined by the requirement for the reliability of flame retention in the “air pocket” created by the channels 202, the upper limit is determined by the simplicity of manufacturing the channels 202 and the reliability of flame retention in the “air pocket”.

The outlet channels preferably have a circular cross-section, however, channels with oval, rectangular, slotted and other cross-sections can be used, which may be preferable for certain combinations of operating parameters of the installation (type of fuel, dimensions of the reactor and the internal space of the furnace, power of the air flow supply system, etc.).

The pressure of the air supplied to the ejectors 103 is selected based on the size and number of output channels, the size of the furnace and reactor, and the fuel parameters.

The uniqueness of the burner locations in the furnace body 100, namely, the combination of the air ejector 103 with the burners (the burner flame has no contact with the furnace and reactor surfaces), guarantees the absence of contact of the burner flame with the furnace body 103 and the reactor. This solution, in combination with the multilayer ceramic fiber thermal insulation, makes the outer contour of the furnace safe (the temperature of the outer surfaces of the furnace body is no more than 45 °C) for the service personnel.

To calculate the optimal heat engineering parameters of the furnace, it was necessary to determine the fuel consumption, the air consumption supplied for combustion, and the flue gas consumption from the installation. In this connection, calculations were made and the following data were determined:

thermal balance of the installation operation;

calculation of heating mode;

calculation of combustion parameters of the liquid fuel used;

fuel combustion characteristics;

arrival of heat;

heat consumption;

fuel consumption.

As a result, the optimal thermal engineering parameters of the furnace were determined to create and maintain the required temperature conditions inside the reactor, installed above the furnace during the process of thermochemical conversion of products located inside the reactor, as well as optimal design solutions.

The specified solutions define the following main parameters:

- the volume of forced air supply into the space between the reactor vessel and the thermal insulation of the outer casing for optimal cooling mode,

- the volume of forced oxygen supply to maintain the required temperature in the firebox,

- the optimal size of the gap between the reactor and the thermal jacket to ensure the most efficient heat transfer mode during heating and maintaining the temperature in the reactor.

Fig. 3 shows the installation in section, where

301 – reactor,

302 – firebox,

304 – thermal insulation,

305 – burner,

306 – flue gas outlet pipe.

The claimed solution may use burner 305 of any standard design, which is not related to its essence. Elements 301, 302, 304 are described in detail above. Pipe 306 is connected by means of a pipe to a wet scrubber. In the scrubber, flue gases are purified by 99.9%.

Fig. 4 shows a diagram of a thermochemical conversion plant, where:

301 – reactor,

302 – firebox,

401 – frame,

402 – block for stabilization of synthetic gas and separation of paraffins, suspended particles and asphaltenes,

403 – heat exchanger block,

404 – gas absorption treatment unit,

405 – gas separator,

406 – fuel filter,

407 - container for draining paraffin and asphaltenes (separated by a partition),

408 – first tank for draining condensate,

409 – second container for draining condensate,

410 – wet scrubber.

The blue arrows in Fig. 4 indicate the flow of the liquid phase, the red arrows indicate the flow of synthetic gas, and the black arrows indicate the flow of flue gases.

The difficulty of creating a thermochemical conversion plant that can be transported and used almost immediately after delivery, or in a version on a wheeled chassis, or after installation on a flat platform (without complex assembly and adjustment), is that a heterogeneous product comes out of the reactor, which cannot be used without preliminary processing. In the claimed device, this problem is solved due to the presence of additional units that separate the reactor output product into fractions, clean these fractions, and ensure its storage in appropriate containers. The input of the claimed plant is supplied with recyclable carbon-containing materials and waste that undergo thermochemical conversion, and the output is paraffins, asphaltenes, a wide fraction of liquid hydrocarbons, dry carbon residue, synthetic gas ready for feeding to burners. The creation of such a plant in a compact mobile design is a non-trivial task that requires creative efforts from specialists in this field of technology to determine the optimal working configuration (layout) of all elements of the claimed plant.

In the declared solution, all equipment is placed on a single platform; the single platform has permitted transport dimensions, which allows the ready-to-use installation to be moved by road, rail, water and sea transport. In one embodiment, the total weight of the installation is about 19 tons. The reactor volume (13-15 cubic meters ( ^m3 )) allows the reactor to be loaded both mechanically and manually in the shortest possible time.

Frame 401 is a rectangular framework on which all elements of the declared installation are installed, has standard shipping units for sea containers. The strength of frame 401 should ensure the possibility of lifting the entire installation using a crane. In one version, frame 401 is made of channels with a height of 180 mm, a width of 70 mm, and a metal thickness of 9 mm. The part of frame 401 opposite to the side of reactor 301 may contain posts and a frame for fastening the installation elements on them, which are on the "upper level" (elements 402-405). Elements 407-409, 410 are installed on the "lower level" of frame 401.

Block 402 is a block for stabilizing synthetic gas and separating paraffin and suspended particles by multiple, for example, four-fold, changes in the direction of movement of the synthetic gas leaving reactor 301. The separated paraffins and suspended particles flow into the lower storage tank 407. The described process is the first stage of purification of synthetic gas.

Then the synthetic gas enters the condenser of heavy fractions (asphaltenes, etc.) via a flue. In the said condenser the synthetic gas is purified for the second time. Through a separate pipeline from the said condenser the liquid fractions flow down into the storage tank 407, located under the condenser at the lower level. The tank 407 contains a partition that forms sections for the products of the first and second stages of purification of the synthetic gas. From the outlet of block 402 the flow of synthetic gas enters the inlet of block 403 via a pipeline.

Heat exchanger block 403 is located on the upper level, it contains two shell-and-tube heat exchangers in the form of two cylindrical tanks connected to each other by means of pipelines, where condensation of synthetic gas occurs. Condensed synthetic gas flows into storage tanks 408, 409 for collecting the condensed fraction. The two shell-and-tube heat exchangers used have a calculated heat exchange surface that ensures maximum condensation of synthetic gas, passing thermochemical conversion in the reactor of 13-15 cubic meters.

The condensed fraction has different densities, each individual shell-and-tube heat exchanger is connected to a separate storage tank 408 and 409. This configuration allows the resulting fraction to be separated by its density at the stage of sequential condensation of synthetic gas.

The used pipeline system with valves allows one pump to pump different condensed fractions without common mixing for further use as a separately obtained product with one density indicator.

From the outlet of block 403, the flow of synthetic gas enters through a pipeline to the inlet of block 404, where it is purified from small suspended particles, passes through a hydraulic seal designed with the possibility of purifying the gas from mechanical impurities remaining after the purifier and directing the gas to gas separator 405.

Block 404 is located on the upper level and is a cylindrical container with a filter element.

Gas separator 405 is located on the upper level and is designed to dry and finely clean the gas and to discharge the cleaned gas suitable for feeding to the burners.

At the lower level of the installation there are a tank 407, a tank 408, a tank 409. These tanks 407-409 are arranged so as not to go beyond the dimensions of the installation, preferably tank 407 is arranged transversely, and tanks 408, 409 along the frame 401, so as to take up as little space as possible. Following tanks 408, 409 there is a wet scrubber 410.

All flue gases of the plant are directed through the flue gas duct to the receiving chamber of scrubber 410. In scrubber 410, flue gases are purified to 99.9%. The flue gas purified after scrubber 410 is directed into the atmosphere through the exhaust fan (creates a vacuum in the cavity between the reactor wall and the heat shield). The presence of a vacuum in the flue gas discharge system ensures explosion and fire safety of the thermochemical conversion system.

The described arrangement provides the possibility of placing the unit on a transportable platform, ready for operation immediately on a wheeled chassis or after unloading onto a prepared site that does not require complex technical solutions (a site made of reinforced concrete slabs, etc.).

Description of the device operation

Before the start of the plant operation, the reactor 301 is loaded with carbon-containing products. Then, the heating burners 305 are switched on, air is supplied to the ejectors 103, the cylindrical reactor 301 is started to rotate, and the temperature inside the reactor 301 is monitored using temperature and pressure sensors. The temperature is brought to the point at which the process of thermochemical conversion of the products begins (the temperature may be different for different products).

The gas obtained as a result of thermochemical conversion is fed to supporting burners 305.

As a rule, the heating of reactor 301 is carried out for 3 hours, and the mode of complete conversion of products lasts for 6-10 hours, after which the installation is cooled, and the products obtained as a result of thermochemical conversion are unloaded from reactor 301.

After which a new technological cycle begins.

After leaving the reactor, the synthetic gas in the gas stabilization tank changes its direction 4 times, thereby separating the most suspended particles (paraffins of various types) from the gas. The separated paraffins flow into the lower storage tank. This is the first part of the purification of synthetic gas.

Then the synthetic gas goes through the flue into the heavy fractions (asphaltenes) condenser. In the condenser the synthetic gas is purified a second time. Liquid fractions of asphaltenes are removed from the condenser through a separate pipeline and flow into the lower tank 407 under the condenser.

The lower tank 407 is divided by a partition, this allows two different compositions (paraffins and asphaltenes) to accumulate in one lower tank 407.

The synthetic gas purified from paraffins and asphaltenes enters the shell-and-tube condensers (2 pcs.) (forming block 403), where the purified gas is condensed. The condensate flows into two lower tanks 408, 409, located under each condenser.

Next, the gas flow from the second condenser is directed to block 404, which is designed to clean the gas from mechanical impurities and direct the gas to gas separator 405, from which it is directed to burners to maintain the thermochemical conversion process.

The installation contains a flue gas exhaust system using an exhaust fan located at the outlet of the wet scrubber 410. The presence of a vacuum in the flue gas exhaust system prevents untreated flue gases from entering the atmosphere.

The proposed design ensures compactness, transportability and quick start-up of the installation.

Option 1 implementation

In one embodiment, the reactor and furnace through the connection unit together with other elements of the installation are located on a single platform measuring 11700x2350 mm. The size of this platform fully corresponds to the overall dimensions of a 40-foot container. The height of all equipment on the platform is 3000 mm - meets the requirements for transport dimensions.

The furnace is located under the reactor and is integral with it. The internal volume of the reactor is 13-15 cubic meters (depending on the configuration), its outlet through the connection unit interacts with other elements of the installation.

The advantages of the proposed installation are as follows.

All the equipment necessary for operation is located on a single platform;

The single platform has permitted transport dimensions, which allows the ready-to-use installation to be moved by road, rail, water and sea transport.

The installation is ready for operation immediately after placement on a flat surface, or in its absence, directly on the transport platform, without assembly and complex adjustments from the manufacturer.

The total weight of the Installation is about 18 tons (complete set);

The heating process takes place in such a way as to protect the reactor and the furnace from flame;

The reactor size (13-15 cubic meters) allows loading the reactor in the shortest possible time, both mechanically and manually. Two employees are involved in the maintenance.

The presence of the entire complex on one installation platform, assembled at the manufacturing plant, allows us to minimize the time of technical installation work after delivery and begin operating the equipment in the shortest possible time.

The equipment package allows it to be put into operation without installation supervision from the manufacturer.

Option 2 of implementation

In one embodiment, the installation additionally comprises a flue gas exhaust system using an exhaust fan located at the outlet of the wet scrubber 410. The presence of a vacuum in the flue gas exhaust system prevents untreated flue gases from entering the atmosphere.

The embodiments are not limited to the embodiments described herein; other embodiments of the invention will become apparent to those skilled in the art based on the information set forth in the description and knowledge of the prior art, without departing from the spirit and scope of the present invention.

Elements mentioned in the singular do not exclude a plurality of elements unless otherwise specifically stated.

The functional connection of elements should be understood as a connection that ensures the correct interaction of these elements with each other and the implementation of one or another functionality of the elements. Particular examples of a functional connection may be a connection with the ability to exchange information, a connection with the ability to transmit electric current, a connection with the ability to transmit mechanical movement, a connection with the ability to transmit light, sound, electromagnetic or mechanical vibrations, etc. The specific type of functional connection is determined by the nature of the interaction of the mentioned elements, and, unless otherwise specified, is ensured by widely known means, using widely known principles in technology.

The methods disclosed herein comprise one or more steps or actions to achieve the described method. The steps and/or actions of the method may be substituted for one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and/or use of specific steps and/or actions may be varied without departing from the scope of the claims.

Although exemplary embodiments have been described in detail and shown in the accompanying drawings, it is to be understood that such embodiments are illustrative only and are not intended to limit the broader invention, and that the present invention is not to be limited to the specific arrangements and structures shown and described, since various other modifications may be apparent to those skilled in the art.

The features mentioned in various dependent claims, as well as the implementations disclosed in various parts of the description, can be combined to achieve useful effects, even if the possibility of such a combination is not explicitly disclosed.

Claims (15)

1. A thermochemical conversion plant comprising a frame on which the following elements are mounted: a furnace with burners and a reactor, implemented in one housing, wherein the first outlet of the housing is connected by a pipeline to the connection unit, the second outlet of the housing is connected to a wet scrubber; a connection unit designed with the possibility of connecting the reactor and the unit for stabilizing the synthetic gas and separating paraffin, suspended particles and asphaltenes; a synthetic gas stabilization and paraffin, suspended particles and asphaltenes separation unit, designed with the possibility of stabilizing the synthetic gas and separating paraffins, other suspended particles and asphaltenes from it, the first outlet of which is connected by a pipeline to a heat exchanger unit, the second and third outlets of which are connected by pipelines to the first and second inlets of a container for draining paraffin and asphaltenes; a heat exchanger unit made in the form of shell-and-tube heat exchangers with the ability to cool and condense synthetic gas, the first outlet of which is connected to a synthetic gas filtration and stabilization unit, the second outlet of which is connected by a pipeline to the inlet of a tank for draining condensate; a filtration and stabilization unit for synthetic gas, designed with the ability to remove finely dispersed inclusions, the outlet of which is connected by a pipeline to a gas separator; a gas separator designed with the ability to dry and finely purify synthetic gas, the outlet of which is connected by a pipeline to the inlet of the gas burners; a container for draining paraffin and asphaltenes, divided by a partition into two parts, one of which is designed to receive paraffin, the second part is designed to receive asphaltenes; containers for draining condensate, the outlets of which are connected by a pipeline to the fuel filter; a fuel filter designed to clean the condensate and deliver the cleaned condensate to an external storage tank via a pipeline; a wet scrubber designed to clean flue gases coming from the reactor; moreover a synthetic gas stabilization and paraffin, suspended particles and asphaltenes separation unit, a heat exchanger unit, a synthetic gas filtration and stabilization unit, a gas separator are located on the upper level of the unit, and a container for the products of the first and second stages of synthetic gas purification, containers for draining condensate, a fuel filter, a scrubber are installed on the lower level, the frame is a rectangular base designed to ensure lifting and loading of the unit. 2. The installation according to item 1, additionally containing a system for removing flue gases using an exhaust fan. 3. The installation according to paragraph 1, in which the dimensions of the installation correspond to the overall dimensions of a 40-foot container.