EP4185658A1

EP4185658A1 - Reactor and method for the pyrolysis of industrial or municipal waste and for the reduction and purification of pyrolysis gas from heavy hydrocarbons and carbon particles

Info

Publication number: EP4185658A1
Application number: EP21846667.0A
Authority: EP
Inventors: Boguslaw KUSZ; Bartosz TRAWINSKi
Original assignee: Gdansk University of Technology
Current assignee: Gdansk University of Technology
Priority date: 2020-07-21
Filing date: 2021-06-29
Publication date: 2023-05-31
Also published as: PL241665B1; PL434735A1; EP4185658A4; WO2022019787A1

Abstract

The invention relates to a method and a reactor for pyrolysis of industrial or municipal waste such as materials selected from the group consisting of underwood chips, wood waste, forest waste, sewage sludge, petroleum coke, municipal solid waste (MSW) or refuse derived fuels (RDF), and for the reduction and purification of pyrolysis gas from heavy hydrocarbons and carbon particles. A reactor for pyrolysis of industrial or municipal waste containing a vacuum-tight chamber is characterized by the fact that the space of the proper chamber is divided into four compartments, inside which there is a thermal insulation made of low-absorbent materials. The charge introduced through the first compartment is pyrolysed in the second compartment, and in the third compartment there is also a shelf on which a layer of carbonizate with a temperature of 850-1000° C is formed, acting as a catalyst for the reduction and purification of pyrolysis gas. The carbonizate layer with a temperature of 900-1000° C passes continuously into the carbonizate column in the fourth compartment with the temperature decreasing with the height of the column. The carbonizate column acts as an additional pyrolysis gas filtering and thermal insulation, and is cooled in its lower part with water. The heating of the charge and carbonizate, necessary for the process, is provided by electric heaters and / or a burner powered by pyrolysis gas. The reactor allows for the continuous process of feeding the charge, its pyrolysis, removal of carbonizate and obtaining purified pyrolysis gas. The invention also relates to a method for the reduction and purification of pyrolysis gas.

Description

Reactor and method for the pyrolysis of industrial or municipal waste and for the reduction and purification of pyrolysis gas from heavy hydrocarbons and carbon particles

The subject matter of the invention is a method and a reactor for pyrolysis of industrial or municipal waste such as materials selected from the group consisting of underwood chips - wooden railway sleepers, wood waste, forest waste, sewage sludge, petroleum coke, municipal solid waste (MSW) or refuse derived fuels (RDF) and for the reduction and purification of pyrolysis gas from heavy hydrocarbons and carbon particles.

Recycling, economic and ecological use of the generated and produced utility or municipal waste is a significant challenge for the economies of many countries. One of the ways to rationally process municipal and industrial waste is to carry out pyrolysis at high temperatures.

Fuel material called charge contains material selected from the group consisting of wood chips, wooden railway sleepers, wood waste, forest waste, sewage sludge, municipal solid waste (MSW), refuse derived fuels (RDF) or any combination of fuels from biomass.

The pyrolysis process requires heating the charge above the temperature of 200⁰ C, which results, among others, in pyrolysis gas with significant amounts of hydrogen, methane and other heavier hydrocarbons. Other gas components are also carbon monoxide and carbon dioxide, nitrogen and its compounds, and hydrogen sulfide.

A by-product of pyrolysis is a carbonizate containing mainly carbon.

The gas obtained as a result of pyrolysis can be used to produce heat, electricity or it can be a source of hydrogen.

In order for the gas obtained as a result of pyrolysis to be used as a source of hydrogen or for the production of electricity by e.g. combustion in an engine driving an electric current generator, it should be cleaned of heavy hydrocarbons, harmful gases and carbon particles. The purification of the pyrolysis gas obtained directly from the pyrolysis reactor chamber from heavy hydrocarbons, tars and gases considered as waste materials and from carbon particles is a problematic process.

Currently, very often, external gas cleaning systems are used to purify pyrolysis gas, using the processes of decomposition of polyatomic particles at high temperatures, freezing at low temperatures and / or purification through the use of various types of filters. These methods are expensive and require additional equipment, which in turn increases the cost of obtaining pyrolysis gas and reduces the energy efficiency of the pyrolysis process. There are also solutions in which pyrolysis gas passes through the carbonizate bed inside the reactor where it is reduced. In order to increase the overall efficiency of the charge pyrolysis process, the pyrolysis reactor often includes a chamber for partially oxidizing the charge or carbonizate with an externally fed oxidant in the form of pure air or pure oxygen. The use of air causes contamination of the obtained gas with a significant amount of nitrogen, while the use of pure oxygen lowers the overall energy gain in the efficiency of the process and creates additional hazards.

Known pyrolysis reactors produce a significant amount of tar in the gaseous product and do not ensure consistent flow and quality of the synthesis gas.

From the patent publication CZ 295171 a three-zone biomass pyrolysis reactor is known comprising vertically oriented, nested cylindrical vessels which define a drying chamber, a distillation chamber and a reduction and combustion chamber, respectively. The reactor is configured in such a way that the gas mixture produced in the drying chamber of the chamber and the distillation chamber can be introduced into the combined reduction chamber for additional gas combustion. The reactor is complicated to build and its parts subjected to high temperature degrade quickly.

From WO 2015/090251, a device for multi-stage gasification of coal fuel is known, comprising a hermetically sealed vertical vessel which is provided with insulation. Inside the vertical reactor chamber there is a pyrolysis chamber adapted to be filled with fuel from above. Below the pyrolysis chamber there is a partial oxidation chamber for the pyrolysis product and a chemical reduction chamber for the pyrolysis gas. The reactor is very complicated in construction, it uses the process of partial oxidation of the pyrolysis product, which is difficult to control, and in the case of the air oxidant, it introduces significant amounts of nitrogen into the pyrolysis gas.

The patent publication CZ 28354 describes a reactor with a vertically arranged pyrolysis chamber, an oxidation chamber and a reduction chamber, in which a homogenizer is located on the lower plate of the reduction chamber. However, it is the arrangement that does not provide a uniform depth of the char bed, leading to undesirable results.

From publication CN 109906264 there is known a vertical zonal reactor with a pyrolysis zone, a partial oxidation zone containing an element with many angled vents and a reduction zone containing an oblique perforated bottom plate on which there is a carbonizate layer reducing pyrolysis gas passing through it. The system does not ensure continuous replacement of the char, which affects the continuity of operation and the quality of pyrolysis gas.

From publication DE102005026764B3 a pyrolysis reactor is known with electric or gas heating of the reaction chamber, the heating causing gasification of the solid char. It is not possible to reduce and purify the pyrolysis gas inside the reactor chamber.

From document US2002095866 a column reactor is known with the decomposition of tars and oils in the hot char layer. The generated gases are discharged from the reactor from the high temperature area - they are not filtered as they flow through the charcoal column at lower and lower temperature. The system is heated by blowing in steam or oxidizing gas and burning.

From document W003018720, a method of removing ash from a gasifier is known. The method consists in dosing hot ash from the bottom of the reactor through a valve to the bottom tank, where the ash mixes with water and thus gets cooled.

A sequence reactor is known from DEI 0216338. There are 5 zones (shelves) through which the material is poured: water evaporation (150 degrees), pyrolysis (500), coking (800), hydrocarbon cracking to CO and H2 (> 1000), oxidation (gassing of remaining carbon) . Transferring between shelves (grates) is supported by an agitator. There is no information about purification by gas filtration by char.

Document US2010050515 describes a pressure-tight columnar carbon gasifier constructed of brick for thermal insulation. The reactor is a two-stage reactor, no information about gas cleaning by coke / ash.

Document W02008058347 describes the design and operation of a device with a heating zone, where the material is heated in contact with expanded surface heated to high temperatures (the charge is poured over the heated conical elements). The system is not pressure tight - there are outlets from the heating zone. Heating takes place by means of blown steam. The maximum temperature specified in the claims is 650 ° C, which does not allow catalyzed decomposition of hydrocarbons in the char.

A system for the pyrolysis of organic material and the gasification of solid pyrolysis products (and tar) is known from the document W00006671. The pyrolysis (~ 500 ° C) and gasification (~ 1000 ⁰ C) processes are carried out in structurally separate chambers. There is also a third (combustion) chamber in which the resulting gases are burnt to heat the remaining chambers. It is placed inside the pyrolysis chamber or separately. The construction requires the transport of mass and heat between individual chambers. In particular, the pyrolysis and gasification processes take place in separate chambers rather than in one functionally divided chamber. Gas flow through the char is not forced - gases from pyrolysis and gasification are released through the outlets. The pyrolysis process requires the separation of gaseous and solid products and transfer of the solid products to the gasification chamber.

The design and operation of a vertical pyrolysis reactor is known from the document PL221298. The reactor consists of an inner pyrolysis zone and a heating zone, which is located between the vertical wall of the pyrolysis chamber and the outer casing of the device. There are heating devices in the heating zone. The charge is poured from the top, which by means of the "roof¹ is directed towards the walls of the pyrolysis chamber (so that it falls down only at the walls, and not through the entire cross-section of the chamber). During the fall, pyrolysis takes place. The gases are discharged through an outlet at the top and the solid products are discharged through the rotary valve into the tank under the pyrolysis chamber.

Document US2017073582 describes a pyrolysis reactor, which operates in such a way that an inert gas is introduced inside, whose forced flow causes gases to escape from the chamber through openings in the side wall.

The disadvantage of the known solutions is the construction of the reactor, which requires the operation of the main elements of the reactor, including the chamber, at very high temperatures, which complicates the construction and reduces the time of failure-free operation.

Moreover, the disadvantage of the known solutions is the inability to purify the pyrolysis gas formed already in the reactor chamber or the possibility of only partial reduction and purification of the gas by means of a carbonizate layer permanently placed inside the reactor chamber. As a result, the gas obtained from known reactor solutions is contaminated and requires an additional purification process, and the process of obtaining high-energy gas from the charge itself is inefficient. During the scientific research on the pyrolysis of the charge, it turned out that in order to obtain pyrolysis gas purified to the maximum extent of heavy hydrocarbons and carbon particles with a high content of hydrogen and carbon monoxide, the pyrolysis gas produced in the reactor chamber should be passed directly through the carbonizate layer at a set temperature of 900- 1000 ° C, hereinafter referred to as the catalyst-cabonizate layer, passing continuously into the carbonizate column with the temperature decreasing with the height of the column to the room temperature at the outlet of the purified gas. The base of the carbonizate column is immersed in water that acts as an additional gas filter, the carbonizate cooling agent and as the pyrolysis gas overpressure regulator in the reactor chamber. The research work has also shown that in order to ensure the proper temperature of the charge and carbonizate and to achieve a very high energy efficiency of the entire process, the vacuum-tight reactor chamber should contain thermal insulation inside the chamber.

On this basis, the invention was provided in the form of a column reactor for the pyrolysis of industrial or municipal waste and for the reduction and purification of pyrolysis gas from heavy hydrocarbons and carbon particles.

The reactor for pyrolysis of hydrocarbon-containing materials, including industrial or municipal waste, is characterized according to the invention by the fact that the space of a vacuum-tight reactor chamber with internal thermal insulation made of low-absorbent materials is functionally divided into four compartments in which the pyrolysis of the charge takes place, as well as the reduction and purification of the gas permeating through the high temperature layer and the carbonizate column with a decreasing temperature with the height of the column towards the outlet of the purified pyrolysis gas.

The original features of the single-chamber reactor, thanks to the possibility of continuous charge feed and continuous carbonizate removal, enables to a continuous process of charge pyrolysis as well as the reduction and purification of pyrolysis gas permeating as a result of overpressure in the chamber, in the constantly renewing carbonizate layer and column.

Construction of the reactor

The reactor is equipped with - comprising such elements as:

1) in the first compartment: charge inlet and a layer of thermal insulation made of nonabsorbent material, 2) in the second compartment: the chargeagitator and around it - a thermal insulation made of non-absorbent material,

3) in the third compartment: a heating column with a heat exchanger, a shelf on which the layer of carbonizate-catalyst is partially supported, and around it - thermal insulation made of non-absorbent material,

4) in the fourth compartment: a carbonizate column surrounded by a thermal insulation made of non-absorbent material, a chamber with cooling and filtering water that maintains the pyrolysis gas overpressure, and a carbonizate removal system.

The method for carrying out the reduction and purification of pyrolysis gas from heavy hydrocarbons and carbon particles sets also invention.

The process of charge pyrolysis as well as the reduction and purification of pyrolytic gas is divided into 4 stages conducted in separate reactor compartments:

1) in the first compartment: controlled supply of the charge to the second compartment and, thanks to thermal insulation, the temperature in the second component is kept at a level that allows for the pyrolysis of the charge,

2) in the second compartment: mixing and pyrolysis of the charge are carried out at a temperature above 200° C,

3) in the third compartment: reduction and purification of pyrolysis gas flowing through the layer of carbonizate-catalyst at a temperature of 900-10000° C,

4) in the fourth compartment: reduction and purification of pyrolysis gas passing through the carbonizate column, which also serves as a thermal insulation, as well as gas cleaning in the water layer, ensuring at the same time maintaining overpressure inside the reactor chamber, and removing excess carbonizate outside the reactor chamber.

Details of each of the processes are described below.

The reactor chamber is positioned vertically, which facilitates the shifting of the charge and carbonizate towards its lower part, where the excess carbonizate is removed. The charge, e.g. RDF, is supplied from the reservoir by a rotary valve through the first compartment, containing thermal insulation from insulating materials with low water absorption, to the area of the second compartment where pyrolysis occurs.

Preferably, the reactor, in the chamber space, comprises a vertical agitatorwith a set of four mixing baldes mounted at an anglethat rotate at a controlled speed and provide for the charge mixing in the second compartment and the downward movement of the pyrolysis solids reactor chamber. The agitator is mounted on the top cover.

It is preferable for the pyrolysis gas to be maintained, by continuous pyrolysis of the charge, at a positive pressure sufficient to force the pyrolysis gas flow in the vacuum-tight tube reactor chamber closed on both sides.charge.

The pyrolysis gas produced as a result of the pyrolysis of the charge in the second compartment of the reactor chamber flows through the layer of carbonizate-catalyst heated to the temperature of 900-10000° C, with a minimum thickness of 10 cm, which is located in the third comartment of the reactor, and flows in the fourth compartment through the carbonizate column with a temperature decreasing along with the height of the column. The layer-column system of a porous carbonizate consisting mainly of carbon and other elements, including iron, calcium or aluminum, acts as a catalyst for the breakdown of heavier hydrocarbons and as a filter for carbon particles.

The carbonizate-catalyst layer in the third compartment partially rests on the char column and partially on a heat-resistant steel shelf in the shape of an inverted truncated cone surface. The shelf is connected to a heat-resistant steel pipe with a diameter equal to the diameter of the opening of the conical surface of the shelf. The pipe is surrounded by an electric heater for heating the carbonizate and the charge. The pipe with the shelf in the third comartment is extended in the area of the fourth compartment by a ceramic pipe.

In another embodiment, in the third and fourth compartments, vertically along the axis of the reactor chamber, there is a heating column located on the base of the reactor for heating the carbonizate in the third compartment and the charge in the second compartment. The heating column is made of a heat-resistant steel pipe closed at the top, inside which there is an electric heater and thermal insulation.

In another embodiment the heating column in part of the third compartment to be made of heat-resistant steel, while in the part of the fourth compartment it is made of ceramics. In yet another design, in the heating column, instead of the electric heater, there is a gas burner supplied with air and the produced pyrolysis gas, which improves the energy balance of the process.

In another preferred embodiment, in the third compartment, at the point of the heating column, a steel heat exchanger in the form of 6 to 12 radially and vertically arranged heat- resistant steel plates is placed, connected to each other on the reactor axis and on the other side to the finished shelf.

In a preferred embodiment, the carbonizate produced from the second component is directed, by the angled stirrer blades and the blades of the heating column or heat exchanger, to the third compartment to form a carbonizate layer catalyzing the gas purification reaction. Then the carbonizate is moved down, creating a carbonizate column reaching as far as the tank located under the bottom cover of the reactor chamber, in which its excess is removed outside the reactor by means of a cell valve.

In another preferred embodiment, the recirculating water, kept at constant level, is introduced into the carbonizate withdrawal vessel, which cools the carbonizate and the bottom of the heating column, maintains a sufficient positive pressure in the reactor chamber, and additionally filters the pyrolysis gas.

In another preferred set-up, the vessel with the removed carbonizate is provided with a shutter-pipe dividing the vessel into two zones with different levels of cooling water and different pyrolysis gas pressures. In the central part of the tank, the gas pressure is greater than the gas pressure in the second zone, where the gas outlet is located, by the hydrostatic pressure resulting from the difference in the level of cooling water in both zones of the tank.

Such invention advantageously leads to an additional purification of the gas in the water. During the entire charge pyrolysis process, appropriate charge temperatures (above 200° C), carbonizate-catalyst (900-1000° C) and the carbonate column are maintained by means of automatic regulation using at least two temperature sensors.

The rate of charge feed and carbonizate removal is adjustable and sufficient to ensure a continuous pyrolysis process and keep the carbonizate-catalyst layer constant above the carbonizate column so that its thickness is not less than 10cm, which ensures a continuous breakdown reaction of heavier hydrocarbons in the carbonizate layer on the top of carbonizate column into lighter fractions and hydrogen and ensures gas filtration from carbon particles.

Preferebly the charge has more than 5 % by weight of iron as iron increases the speed and efficiency of the reduction and purification process. The charge with a lower iron concentration is preferably mixed with iron oxide in the form of micro- or nano-grains in an amount to achieve a concentration of 5% by weight of iron in the charge introduced to the reactor.

Preferably a thermal insulation is used, minimum 10 cm thick, made of non-absorbent materials inside the steel chamber of the reactor.

The invention makes it possible to efficiently carry out the pyrolysis of the charge as well as the reduction and purification of the pyrolysis gas formed. Thanks to the column structure with a vacuum-tight chamber, the reactor is cheap to make and has little emergency. Moreover, the reactor is safe because damage to the reactor chamber and / or damage to its casing will not result in uncontrolled combustion of pyrolysis gas inside the reactor.

The invention is illustrated in more detail in the examples and in the figures. Fig. 1 shows the structure of the column reactor in cross section, Fig. 2 shows the structure of the column reactor in cross section in another solution, with a gas burner in the heating column, while Fig. 3 shows the structure of the reactor with a heat exchanger without a heating column.

The invention is described in the examples and in the figures:

Fig. 1 Structure of a column reactor in cross-section, with an electric heater in a heating column.

Fig. 2 Structure of a column reactor in cross section in another set-up, with a gas burner heating column.

Fig. 3 Structure of a column reactor in cross-section, with a heat exchanger and without a heating column.

Example. 1. a / construction The reactor chamber (1) is made of tubular stainless steel with the following dimensions: diameter 0.3 m, height 1.0 m, wall thickness 2 mm. The chamber (1) is covered from the outside with a 15 cm thick thermal insulation jacket made of ceramic wool.

The tubular reactor chamber is closed with the lower cover (3) and the upper cover (4) and sealed with silicone gaskets (5). The covers (3) and (4) are connected to the base (6) by means of four construction threaded rods (7) with nuts (8).

In the upper cover there is a container (9) for the charge (10) and a cell valve (11).

In the first compartment (Cl), the charge is dosed through the channel in the thermal insulation made of silicate brick (12).

In the second compartment (C2), the charge (13) heated to a temperature above 200° C undergoes pyrolysis.

In the third compartment (C3), under the heated charge, there is a layer of carbonizate- catalyst (14) with a temperature of 900° C, partially located on a heat-resistant steel shelf, inclined at an angle of min. 30° (15).

In the fourth compartment (C4), the shelf (15) is connected to a heat-resistant steel pipe (16) with an inclined wall of min. 15° to the vertical axis. The pipe (16) is surrounded by an electric heater (17) powered by electrical transitions (18), which serves to maintain the temperature of the carbonizate-catalyst (14) in the third compartment (C3) at the level of 900° C. Heat resistant steel tube (16) is connected to a conical ceramic tube (19) which rests on the lower cover (3). The carbonizate-catalyst layer partially rests on the carbonate column (20) collected in the tube (19). The base of the carbonizate column is located in the tank (21), from which the excess carbonizate is removed by means of a cell valve (22).

The tank (21) contains water (38) cooling the carbonizate and the lower part of the heating column. Recirculated water is introduced through a tube (36) and exited through a tube (37) and kept constant 5 cm above the lower edge of the tube (39) regulating overpressureinside the reactor chamber.

The pyrolysis gas cleaned in the carbonizate column is discharged from the tank (21) through a pipe (40) placed above the cooling water level (38).

Thermal insulation of components (Cl), (C2), (C3) and (C4) is provided by thermal insulation (12), (23) and (45) made of silicate bricks.

On the reactor axis there is a rotary agitator (25) with blades (26) mixing the charge. Four symmetrically placed agitator blades are attached at an angle of about 45° to the agitator axis. The bearings (27) in the top cover (4) enable the agitator (25) to rotate around the vertical symmetry axis of the reactor at a speed of approx. 1 -2 revolutions / min. The lower end of the agitator shaft (25) rotates on a plain bearing (28) located on the cover of the heating column (29).

The heating column (29) is a vertical heat-resistant steel pipe closed at the top, placed on the base of the reactor (6). In the upper part of the heating column (29) there are at least four blades (30) attached at an angle of about 135° to the axis of the chamber, , which heat the charge and the carbonizate and direct the mixed carbonizate moved by the paddles (26) of the agitator (25), down the reactor, where the carbonizate column ( 20) is formed.

Inside the heating column (29), in the zone of the third (C3) and fourth (C4) compartments, there is an electric heater (31) with a power cord led out at the bottom (32) of the heating chamber. Inside the heating column (29) there is a layer of thermal insulation (33) made of mineral wool.

Measurement of the charge temperature in the component (C2) is provided by the thermocouple (34), and the temperature of the carbonizate-catalyst in the component (C3) is measured by the thermocouple (35), both of K-type.

All passages through the cover (3) and (4) of the reactor are bolted passages using silicone gaskets. The working temperature of the chamber (1) at the point of contact with the covers (3) and (4) does not exceed 40° C. b / methodology

The charge was pyrolysed in the form of a RDF pellet (Refuse-Derived Fuel) with an iron content in the resulting carbonizate of 5% by weight.

Start-up of the reactor, in which the carbonizate column (20) and the carbonizate-catalyst layers (14) are initially located, takes place by switching on the heaters (17) and (31) with a maximum power of 1.5 kW each. After reaching the temperature of 900° C in the carbonizate layer (14), the charge is introduced into the reactor compartment (C2) by means of a rotary feeder (11) at a rate of 0.2 kg / min. The charge falls onto the layer of carbonizate-catalyst, heated to a temperature of at least 900° C, and is mixed by means of the stirrer arms.

As a result of heating the charge in the form of RDF pellets to a temperature above 200° C, pyrolysis occurs, gas is released and a carbonizate is formed. The carbonizate stirred by the agitator is systematically transferred to the third compartment and heated in this compartment to the temperature of 900° C, and then directed down the reactor to form a carbonizate column. The thermocouple (34) measures the temperature of the charge in compartment (C2). The pyrolytic gas formed in the second (C2) and third (C3) compartments, due to an overpressure of 3000Pa, penetrates through the carbonizate- catalyst layer (14) and through the carbonizate column (20), passes through the cooling water layer (38) and then is discharged through the output (40). The excess carbonate from the base of the column (20) is discharged by means of a cell feeder (22).

To ensure the continuous operation of the reactor, the rate of carbonizate production is equal to the rate of removal from the reactor, c / process efficiency:

After reduction and purification in the carbonizate, after cooling and final filtering of residual carbon particles and heavier hydrocarbons in a water scrubber located in the lower tank, the pyrolysis gas can be used, for example, to power an internal combustion engine driving a power generator or to obtain pure hydrogen. The reactor described in Example 1 stably, safely and continuously converts RDF (Refuse-Derived Fuel) pellets into pyrolysis gas. In the described example of the reactor, gas is obtained with the following volumetric composition: 45% hydrogen, 48% carbon monoxide, 5% methane and 2% other gases, including carbon dioxide and nitrogen. The residual liquid in this process accounts for no more than 3% by weight of the charge amount.

Example 2 a) construction

The reactor is constructed as described above and, additionally, in Fig. 2. In the heating column (29), instead of the electric heater (31), there is a gas burner (43) with pipes (42) supplying pyrolysis gas produced in the reactor and air, and an exhaust outlet (44). b) methodology

The process of supplying and pyrolysing the charge in the form of RDF pellets and heating, forming and removing the carbonizate and purifying the gas is described in Example 1, with the heating of the charge and carbonizate by burning the produced pyrolysis gas in air supplied to the burner in a heating column. During the reactor start-up, it is required to temporarily use an additional flammable gas, e.g. butane from a cylinder. c) the effectiveness of the process After cooling and finally filtering off the residual carbon particles and heavier hydrocarbons in a water scrubber located in the lower carbonizate tank, pyrolysis gas can be used, for example, to power an internal combustion engine driving an electric generator or to obtain pure hydrogen.

In the described example of the reactor, gas is obtained with the following volumetric composition: 43% hydrogen, 48% carbon monoxide, 7% methane and 2% other gases, including carbon dioxide and nitrogen. The residual liquid in this process accounts for no more than 3% by weight of the charge amount. The use of pyrolysis gas for heating increased the overall energy efficiency of the RDF to pyrolysis gas conversion process by 10%.

Example 3 a) construction

The reactor is constructed as described above and, additionally, in Fig. 3. Instead of the heating column (29), there is a heat exchanger (41) heated by an electric heater (17). b) methodology

The process of supplying and pyrolysing the cahrge in the form of RDF pellets and heating, forming and removing the carbonizate, as well as reducing and purifying the gas is described in example 1, whereby the heating of the charge and carbonizate is performed with an electric heater (17) via a heat exchanger (41). c) the effectiveness of the process

After cooling and finally filtering out the residual carbon particles and heavier hydrocarbons in a water scrubber in the lower carbonizate tank, pyrolysis gas can be used, for example, to power an internal combustion engine driving an electric generator or to obtain pure hydrogen.

In the described example of the reactor, gas is obtained with the following volumetric composition: 40% hydrogen, 47% carbon monoxide, 7% methane and 6% other gases, including carbon dioxide and nitrogen. The residual liquid in this process accounts for no more than 4% by weight of the charge amount. The use of a heat exchanger in the charge and carbonizate heating process simplifies the construction of the reactor.

Example 4 a) construction

The reactor is constructed as described in Examples 1, 2 or 3. b) method

The process of supplying and pyrolysing of the cahrge in the form of RDF pellets, and heating, forming and removing the carbonizate and purifying the gas is described in Example 1, 2 or 3. Additionally, the catalytic purification of pyrolysis gas is supported by an additional catalyst, e.g. iron oxide in the form of micro- or nano-grains introduced together with the charge of up to 5% by weight to the charge. When working in a reducing atmosphere, nano and micro iron granules are preferably formed, which significantly accelerates the process of reduction and purification of pyrolysis gas. c) the effectiveness of the process

After cooling and finally filtering off the residual carbon particles and heavier hydrocarbons in a water scrubber located in the lower carbonizate tank, pyrolysis gas can be used, for example, to power an internal combustion engine driving an electric generator or to obtain pure hydrogen.

The use of an additional catalyst increased the percentage of hydrogen in the pyrolysis gas. In the described example of the reactor, gas is obtained with the following volumetric composition: 50% hydrogen, 47% carbon monoxide, 1% methane and 2% other gases, including carbon dioxide and nitrogen. The residual liquid in this process accounts for no more than 2% by weight of the charge amount. The use of a catalyst in the process increased the overall efficiency of the RDF to pyrolysis gas conversion process by more than 12%.

Example 5 a) construction

The reactor is constructed as described in Examples 1, 2 or 3. Additionally it contains no water (38) in the vessel (21) and the pyrolysis gas after purification in the layer (14) and the column (20) of the carbonizate is directly discharged through the tube (40). b) method

The process of supplying and pyrolysing of the charge in the form of RDF fpellets, and heating, forming and removing the carbonizate and purifying the gas is described in Example 1 , 2 or 3 with no additional pyrolysis gas filtration in the water layer. c) the effectiveness of the process The lack of water in the tank (21) simplifies the design, however, it increases the amount of heavier hydrocarbons in the pyrolysis gas by 1 percentage point. In the reactor described in the example, the following gas composition is obtained: 50% hydrogen, 45% carbon monoxide, 1% methane and 4% others gases including carbon dioxide and nitrogen. The residual liquid in this process accounts for no more than 4% by weight of the charge amount.

In addition, the lack of water reduces the possibility of cooling the carbonizate and causes the temperature of the tank (21) to rise to about 80° C.

Example 6. a) Description of the pyrolysis method:

The pyrolysis of the charge in the form of RDF pellets takes place when the charge reaches a sufficiently high temperature of at least 200° C. In the reactor with direct reduction and purification of pyrolysis gas, as described in Examples 1-5, the heating of the charge takes place when the charge introduced into the chamber falls into the carbonizate layer heated to a temperature of at least 900° C and is stirred by means of the stirrer blades. As a result of heating the charge, its pyrolysis takes place, gas is released and a carbonizate is formed. The carbonizate stirred by the stirrer is transferred to the third compartment and heated in this compartment to the temperature of 900-1000° C, and then it is directed down the reactor to form a carbonizate column. The excess carbonizate from the carbonizate column is removed in the tank at the bottom of the reactor chamber. To ensure the continuous operation of the reactor, the rate of char production is equal to the rate of removal from the reactor. b) Description of the treatment of the resulting gas:

In the vacuum-tight reactor chamber, the pyrolysis gas produced reaches a state of overpressure caused by high resistance to penetration through the porous carbonizate and the hydrostatic pressure of the water layer. The overpressure of the gas in the order of 3000 Pa causes that the pyrolysis gas on its way outside the reactor must pass through the porous layer of the carbonate-catalyst and the column of the carbonate in the third and fourth compartments. The carbonizate from the third and fourth compartments, heated to high temperature, has catalytic properties favoring the breakdown of heavier hydrocarbons into hydrogen and lighter hydrocarbons, and favoring the formation of carbon monoxide. During the gas penetration through the carbonizate, the pyrolysis gas is reduced and purified, as well as filtered from solid particles, e.g. coal.

The thermal insulation in the first compartment, made of the low-water absorption insulation materials causes the gases and tar condensing near the top cover to flow by gravity into the second compartment, where they are heated, and then undergo further decomposition in the carbonizate layer into simple hydrocarbons and hydrogen.

When thermal insulation in the second, third and fourth compartment is mades of insulating materials with low water absorption, the tars condensing in the lower part of the reactor fill a small space free from insulation, sealing the fourth compartment. The method of reducing, purifying and filtering gas in the carbonizate-catalyst layer and in the carbonizate column, as well as the use of thermal insulation inside the chamber made of low-absorbent materials, minimizes the amount of liquid waste or tars produced, which significantly increases the efficiency of the process of converting the charge into gas.

It is clear that the above-mentioned examples of set-up of the present invention are only exemplary and can be composed in various ways. These changes, now or in the future, should not be construed as departing from the spirit and scope of the invention, and all such modifications are intended to fall within the scope of the appended claims.

Claims

1. Reactor for pyrolysis of industrial or municipal waste such as materials selected from the group consisting of wood chpis, railway sleepers wood, wood waste, forest waste, sewage sludge, petroleum coke, municipal solid waste (MSW) or refuse derived fuels (RDF) and for reduction and purification of pyrolysis gas from heavy hydrocarbons and carbon particles i characterized in that a vacuum-tight reactor chamber (1) with vertical structure is functionally divided into four compartments, comprising an upper compartment (Cl) where under a cover (4) of the reactor chamber (1) there is thermal insulation (12) made of low-absorbent materials, and a second compartment (C2) of the charge pyrolysis with thermal insulation (45) made of low-absorbent materials, where a blades (26) of an agitator (25) mix charge (13) and where the charge is being heated to a temperature above 200° C, and a third compartment (C3) comprising a heating column (29) with an electric heater (31) or optionally with a pyrolysis gas burner (43), a the heated to a temperature of 900-1000° C, within a process of reduction and purification of pyrolysis gas is being performed, and a fourth compartment (C4) that comprises under the carbonizate layer (14) and the carbonizate column (20) made of low-absorbent materials, thermal insulation (23), and, under a bottom cover (3), a container (21) for carbonizate and cooling water (38) introduced with a tube (36) and an output tube (37) and a carbonizate discharge system (22) and a purified pyrolysis gas outlet (40).

2. The reactor according to claim 1, wherein in the first, second, third and fourth compartments, a thermal insulation made of low-absorbent materials is located in the vacuum-tight reactor chamber.

3. The reactor according to claim 1 or 2, whwrein in the third compartment there is a carbonizate layer heated to a temperature of 900-1000° C that sets a catalyst for the reduction and purification of pyrolysis gas, and that pass continuously in the fourth compartment into a carbonizate column (20) with a temperature decreasing with height, which is catalyst, filter and thermal insulation, and enable the flow, cooling and additional purification of pyrolysis gas to be performed.

4. The reactor according to claim 1, 2 or 3, wherein in the fourth compartment, the lower part of the carbonizate column is immersed in continuous-flow water (38) that enables cooling the carbonizate to be performed and the lower part of the heating column, enabling additional pyrolysis gas purification to be performed acting as a regulator of pressure inside the reactor chamber.

5. The reactor according to claim 1, 2, 3 or 4, wherein a moving agitator rotating along the axis of the reactor with blades inclined at an acute angle to the axis of the blades directs the charge and carbonizate from the second compartment to the area of the stationary blades of the heating column (30) or the heat exchanger (41) in the third compartment, thanks to which the carbonizate-catalyst layer (14) is formed and continuously supplemented, together with the carbonizate column (20).

6. Method of pyrolysis of industrial or municipal waste such as materials selected from the group consisting of wood chips, wooden railway sleepers, wood waste, forest waste, sewage sludge, petroleum coke, municipal solid waste (MSW) or refuse derived fuels (RDF), and then reduction and purification of the pyrolysis gas obtained from the pyrolysis of heavy hydrocarbons and carbon particles inside the vacuum-tight reactor chamber is characterized in that the process is preformed in a reactor divided into four compartments, where the pyrolysis material is being collected in the first compartment, and then the charge in the second compartment is being mixed and is being heated to a temperature above 200° C and the pyrolysis is being performed, thensupplying of the pyrolysis gas to the surface of the carbonizate-catalyst that has a temperature of 900-1000° C in the third compartment is continuously performed, while the reduction and purification are being carried out, while the produced carbonizate is continuously replenishedwith a layer of carbonizate-catalyst and the excess of carbonizate from the carbonizate-catalyst layer is continuously supplemented by the carbonizate located below the carbonizate-catalyst layer in the fourth compartment with a temperature that decreases along with the height of the column, and the reduction and purification of pyrolysis gas is performed through the forced overpressure flow of pyrolysis gas through the carbonizate-catalyst layer and a carbonizate column, and the purified gas is withdrawn by the positive pressure forced gas flow through the water layer maintaining the gas excess pressure in the reactor chamber, and excess carbonizate is discharged from the reactor chamber to the bottom of the fourth reactor compartment from the base of the carbonizate column immersed in the water layer.