An oxidation device and a method for cleaning emissions from technological processes using thermochemical recuperation

Abstract

The invention relates to an oxidation device for the cleaning of emissions from technological processes, in which, in addition to thermal recuperation, chemical recuperation is also carried out, wherein the oxidation device comprises: - an oxidation chamber for the oxidation of the said emissions; - a burner system for raising the temperature of the emissions to the oxidation temperature; - a discharge line extending from the oxidation chamber to the thermochemical recuperation system; - there is a thermochemical recuperation system, which is at least partially mounted adjacent to the oxidation chamber and utilizes the heat of the exiting cleaned emissions to modify the chemical composition and increase the calorific value of the hydrocarbon gas before it reaches the burner; wherein the thermochemical recuperation system comprises: • a preheater arranged to raise the temperature of the mixture of steam and hydrocarbon gas to a temperature required for a stable steam reforming process, the preheater having a mixing chamber connected at least to a hydrocarbon gas supply and a steam supply as a source of hydrogen and oxygen, and • a reformer, which may be designed in any manner, and is adapted for chemical catalytic reaction between the gas and the steam to optimize the process of thermal oxidation of the emissions, • an outlet through which the gas output from the reformer is directed back into the oxidation chamber, a discharge conduit leading from the thermochemical recuperation system to a chimney or an additional heat exchanger or a similar outlet for discharging cleaned emissions into the surrounding atmosphere.

Description

[0001] AN OXIDATION DEVICE AND A METHOD FOR CLEANING EMISSIONS FROM TECHNOLOGICAL PROCESSES USING THERMOCHEMICAL RECUPERATION

[0002] Field of the invention

[0003] The invention belongs to the field of physical and chemical processes carried out with the aid of a catalyst, in which gaseous substances react with other gaseous substances, as well as to the field of devices for the thermal treatment of emissions arising from technological processes. The invention relates to an oxidation device and a process for cleaning emissions from technological processes by means of thermochemical recuperation. The invention is suitable for thermochemical heat recuperation in the cleaning of emissions from technological processes which may contain volatile emissions, organic and inorganic impurities, and other gaseous components, wherein the cleaning process with the oxidation device is based on the thermal oxidation of the said emissions.

[0004] Background of the invention and the technical problem

[0005] Emissions from technological processes are contaminated with volatile emissions, primarily of organic origin, but they may also contain organic or inorganic matter, always in a gaseous state, such as hydrocarbons, ammonia, dioxins and the like, and they may further contain non-combustible dust. Such emissions may constitute process gases in accordance with European standards (EN 12753:2005) and guidelines (VDI 2442), or may be of another type. The said emissions must be cleaned prior to release into the environment so as to comply with the criteria of existing standards and guidelines. The technical problem is to design an oxidation device that enables efficient heat recuperation during the cleaning of emissions, and thereby reduces the consumption of an additional energy product required for heating the gases in the oxidation device. At the same time, the purpose of the invention is to provide a corresponding process for the cleaning of emissions and the simultaneous recuperation of heat. The aim of the invention is to clean emissions to such an extent that, in accordance with existing standards and guidelines, they may be released back into the atmosphere without environmental harm and with minimal CO2 and greenhouse gas emissions, while maximizing the utilization of the heat contained therein in order to reduce energy consumption.

[0006] Prior art

[0007] In the field of the technical problem, a device for thermal oxidation is well known, and is described in standard EN 12753:2005+A1:2010. This device comprises a supply conduit, by means of which the device is connected to the source of emissions. The temperature of a contaminated emission from a technological process, containing impurities of organic origin in a gaseous state, generally ranges from 100 to 400 °C, most commonly around 200 °C. The said supply conduit leads to a heat exchanger, from which the flow is directed in a closed manner into an oxidation chamber. Inside the heat exchanger, the emission is heated to a temperature of approximately 400 to 700 °C, in most cases to about 650 °C, by means of already oxidized gases exiting the aforementioned oxidation chamber. In the said oxidation chamber, a gas burner is installed in which natural gas is combusted together with the required quantity of air, in order to maintain the temperature inside the oxidation chamber at no less than 820 °C, and typically at least around 870 °C, thereby establishing the conditions for effective thermal oxidation of the gaseous emissions. After the reaction in the oxidation chamber, oxidized gases exit therefrom at a temperature of approximately 820 to 870 °C and enter the heat exchanger, wherein a portion of the heat is transferred to the incoming gases. In the section between the reaction chamber and the heat exchanger, a primary supply of atmospheric air at room temperature, approximately 30 °C or less, may optionally be provided and admixed to the oxidized gases exiting the reaction chamber. This is done for the purpose of reducing the temperature of the stream to approximately 750 °C prior to its entering the heat exchanger, thereby establishing a sustainable operating regime for the heat exchanger and achieving an acceptable service life thereof. Similarly, in the section between the heat exchanger and the final discharge of oxidized gases, a secondary supply of atmospheric air at room temperature, approximately 30 °C or less, may be added, in order that (for example) after the filtration of solid particles and their passage through a chimney, the final temperature of the oxidized gases discharged into the atmosphere can be kept at a reasonable and acceptable value, which does not cause inconvenience or even danger to living organisms or to the environment in general.

[0008] The problem with the solution described is that, due to the high temperature of the emissions, it is not possible to recuperate them completely, since the high temperature would destroy the heat exchanger, or if high-temperature steel were used for the manufacture of the exchanger, the exchanger would become so costly that it would not be economically viable. Furthermore, the formation of undesirable substances — such as nitrous oxide, which can be completely decomposed only at temperatures above 1000 °C — is possible. Finally, the introduction of cold air results in the rejection of the highest fraction of waste heat.

[0009] Description of the solution to the technical problem

[0010] The invention upgrades existing solutions and addresses the disadvantages of known solutions. The technical problem is solved as defined in independent claims, wherein the preferred embodiments of the invention are defined in dependent claims.

[0011] The invention is suitable at least for thermochemical heat recuperation during the cleaning of emissions from technological processes, which may contain dust, volatile emissions, organic and inorganic impurities, and other components in a gaseous state and / or dust, wherein the cleaning process with the oxidation device is based on the thermal oxidation of the said emissions.

[0012] The invention incorporates an oxidation device for the cleaning of emissions from technological processes, which according to the invention is designed so that at least thermochemical recuperation can be carried out therein. The oxidation device comprises: - an oxidation chamber configured for the oxidation of the said emissions, with an inlet opening connected to a supply of emissions and an outlet opening through which cleaned emissions leave the oxidation chamber,

[0013] - a burner system for raising the temperature of the emissions to the oxidation temperature, wherein:

[0014] o there are at least two burners in the oxidation chamber, namely at least one first burner and at least one second burner; wherein a first conduit extends from outside the oxidation chamber to at least one first burner and is arranged to supply a hydrocarbon gas from an external source; and wherein a second conduit is arranged to supply and steam and a hydrocarbon gas to the second burner via a thermochemical recuperation system, or o there is at least one burner in the oxidation chamber, to which a separate first conduit and second conduit are connected,

[0015] - a discharge line extending from the said outlet opening of the oxidation chamber to the inlet opening of the thermochemical recuperation system,

[0016] - a thermochemical recuperation system, which is at least partially mounted adjacent to the oxidation chamber and utilizes the heat of the exiting cleaned emissions to modify the chemical composition and increase the calorific value of the hydrocarbon gas before it reaches the burner; wherein the thermochemical recuperation system comprises:

[0017] o a preheater arranged to raise the temperature of the mixture of steam and hydrocarbon gas to the temperature required for a stable steam reforming process, with a mixing chamber connected to at least a hydrocarbon gas supply and a steam supply as a source of hydrogen and oxygen, and o a reformer, which may be designed in any suitable manner, and is configured for chemical catalytic reaction between the gas and the steam to optimize the process of the thermal oxidation of the emissions; wherein the reformer comprises at least one, and preferably several, tubes, which may have the same or different diameters; and wherein at least one catalyst, preferably several catalysts, is / are arranged inside the said tube(s), the catalyst(s) being disposed along the entire tube, along only one part of the tube, or in several separate sections of the tube, such that the gas mixture supplied from the preheater can come into contact with the catalyst,

[0018] o an outlet through which the gas output from the reformer is directed back into the oxidation chamber,

[0019] - a discharge conduit leading from the thermochemical recuperation system to a chimney or similar outlet for discharging the cleaned emissions into the surrounding atmosphere.

[0020] The device enables recuperation of a greater percentage of energy than solutions known to date, and consequently both reduces the consumption of a gaseous energy product and decreases CO2 emissions arising from the fuel consumed.

[0021] In a possible embodiment, the temperature required for a stable steam reforming process depends on the selected catalyst, but is typically at least 700 °C.

[0022] Preferably, the hydrocarbon gas is CH4. A section of the supply line, connected to a source of natural gas and to a source of water, may thus be connected to the mixing chamber of the preheater, wherein natural gas and water (in the form of steam) are mixed, preferably in a molar ratio from 1:2 to 1:1; ideally as close as possible to 1:1, since at higher ratios an excessive amount of carbon dioxide is formed, which hinders the recuperation of heat.

[0023] In a possible embodiment, the oxidation device may comprise a burner system provided with an additional supply of air or oxygen.

[0024] In a possible embodiment, the preheater may comprise a mixing chamber additionally connected to a supply of flue gases and / or CO and / or oxygen and / or air. By supplying these, the likelihood of catalyst degradation can be reduced.

[0025] The catalyst is a commercially available component having a catalytic layer deposited on a given support, and in possible embodiments of the oxidation device may, according to the invention, be arranged along the entire tube, along only one part of the tube, or along several separate parts of the tube. If the catalyst is arranged on several separate parts of at least one tube, the reformer further comprises at least one spacer, which may be designed in any form. For example, it may be a cylindrical element with through-holes, a torus, or any other element having at least one passage opening such that gases can flow from one part with catalyst to another part with catalyst. In possible embodiments, a specific type of tube with a predetermined arrangement of catalysts and spacers is deliberately installed based on expected conditions. In the construction of the thermochemical recuperator, any suitable catalyst may be used; however, the catalyst preferably comprises an appropriate metal selected from the group comprising nickel (Ni), cobalt (Co), copper (Cu), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), and platinum (Pt), as well as any combinations thereof. A suitable catalyst is selected depending on the type of fuel.

[0026] In one embodiment of the process according to the invention, the mutual distances between two adjacent catalysts are equal. In an alternative embodiment of the process according to the invention, the mutual distances between adjacent catalysts are different, wherein in possible embodiments the mutual distances decrease proportionally in the direction from the connecting chamber toward the homogenizing chamber, and wherein the ratio between each preceding mutual distance and each subsequent mutual distance between adjacent catalysts is determinable in advance depending on the anticipated course of chemical reactions in the thermochemical recuperator during the implementation of the process.

[0027] In a possible embodiment, the recuperator may further comprise chambers that separate or combine the flows of individual reformer tubes.

[0028] In possible embodiments, a cooling system may be provided between the discharge line and the thermochemical recuperation system, by means of which, if necessary, the temperature of the cleaned emissions is reduced in order to prevent degradation of the catalysts and of the components of the device. Optionally, the oxidation device according to the invention may additionally comprise a heat exchanger arranged downstream of the thermochemical recuperator, wherein at least a portion of the cleaned emissions is directed into the heat exchanger, in which a further portion of the heat of the cleaned emissions is recuperated, whereby at least part of the heat is transferred to the incoming stream of emissions from technological processes which are conducted into the oxidation chamber.

[0029] The oxidation device for the cleaning of emissions from technological processes described above, which includes a thermochemical recuperation system, successfully solves the technical problem, meaning that more efficient heat recuperation is achieved during cleaning of the emissions, and thereby reduced consumption of additional energy product for heating the gases in the oxidation device.

[0030] The device may be used for energy recuperation in the cleaning of emissions from technological processes that contain volatile emissions, organic and inorganic impurities, and / or other components in a gaseous state.

[0031] The invention further relates to a process for the cleaning of emissions by means of the thermal oxidation of the said emissions; wherein the process comprises the following steps:

[0032] i. collecting emissions, which generally have a temperature between 100 and 400 °C, preferably about 200 °C, in a supply conduit;

[0033] ii. directing the collected emissions from the supply conduit into the heat exchanger, wherein the emissions in the said heat exchanger are heated to a temperature preferably between 400 and 700 °C, more preferably about 650 °C; iii. directing the heated emissions into the interior of the oxidation chamber, wherein, at a temperature generally of at least 820 °C, preferably at least 870 °C, in the presence of at least one gas burner combusting a carbon-containing gas, in particular natural gas or methane or biomethane or mixtures thereof, the emissions are subjected to thermal oxidation for a duration sufficient to achieve complete thermal oxidation of the organic impurities contained in the emissions; iv. directing the oxidized emissions to the heat exchanger, where they transfer heat to fresh emissions entering the process and passing through the heat exchanger in step ii, such that the temperature of the oxidized emissions in the discharge line, i.e. after exiting the heat exchanger, is reduced;

[0034] v. directing the cooled emissions from the preceding step through a discharge conduit, optionally to filtration of mechanical particles in a filter, after which the emissions, at a temperature generally not exceeding 250 °C, are discharged into the surrounding atmosphere via a chimney or similar outlet.

[0035] In one embodiment of the aforementioned process, in step iv), such an amount of clean ambient atmospheric air at room temperature, up to 30 °C, is added to the cleaned emissions having a given temperature in the discharge conduit after exiting the oxidation chamber and prior to entering the heat exchanger, that the temperature of the stream entering the heat exchanger via the discharge conduit does not exceed the permissible temperature of the heat exchanger, and generally does not exceed 750 °C.

[0036] A further variant of the process is also possible, wherein in step v), either in combination with the preceding process variant or independently thereof, such an amount of clean ambient atmospheric air at room temperature, up to 30 °C, is added to the cleaned emissions in the discharge conduit after exiting the heat exchanger and prior to filtration in the filter and discharge into the surrounding atmosphere through the chimney or a similar outlet, that the temperature of the cleaned emissions passing through the filter and the chimney or similar outlet into the atmosphere does not exceed a predetermined temperature, which generally does not exceed 250 °C and at which the effects of the cleaned emissions released into the atmosphere remain within acceptable limits.

[0037] The process according to the invention further comprises an additional step, wherein: - vi) in a sixth step, after establishing the process according to the above-mentioned steps i) to v) and / or at least one of the two further variants of the process according to steps i) to v), it is ensured that the cleaned emissions, which upon exiting the oxidation chamber through the outlet opening have a temperature of preferably at least 820 to 850 °C, are directed, in the section between the oxidation chamber and the above-mentioned heat exchanger, also through the thermochemical recuperator as described above, in such a manner that the emissions cleaned of organic impurities are directed from the discharge conduit into the interior of the thermochemical recuperator, such that the hot cleaned emissions from the discharge conduit first flow through the reformer, preferably through the gaps between the outer surfaces of reformer tubes arranged side by side, and, immediately after passing through the reformer, through the preheater, preferably through the gaps between the outer surfaces of preheater tubes arranged side by side, after which the cleaned emissions, upon exiting the thermochemical recuperator, are again conducted via the discharge conduit, in accordance with the previously described fourth step (iv), into the heat exchanger and, in accordance with the previously described fifth step (v), into the surrounding atmosphere.

[0038] Furthermore, in the process according to the invention, it is also envisaged that, through a further step (vii), the following may be performed:

[0039] - water and a hydrocarbon gas, preferably natural gas, typically natural gas or biogas with a sufficient methane content, are supplied,

[0040] - and an additional supply line is provided, the primary section of which extends from said source of water and a hydrocarbon gas into the thermochemical recuperator, while the secondary section of the said supply line leads from the thermochemical recuperator to a second gas burner located in the oxidation chamber, wherein the water and the methane-comprising natural gas from the said source are conducted via the primary section of the additional supply line into a mixing chamber that constitutes the inlet to the said thermochemical recuperator, such that in the mixing chamber a mixture of water and gas, preferably methane, is formed in a molar ratio from 1:2 to 1:1, after which the thus-obtained mixture of water and methane- comprising gas is conducted from the said mixing chamber through the preheater of the said thermochemical recuperator, namely through the interior of the preheater tubes, wherein the said gaseous mixture of steam and methane- comprising gas is heated to a temperature of at least 750 °C, after which the thus- heated gaseous mixture is conducted via the connecting chamber into the interior of the reformer tubes, where, in the presence of catalysts, synthesis gas (syngas) is formed, i.e. a mixture of hydrogen and carbon monoxide, typically in a ratio of about 75% H2 and 25% CO, which is collected in a homogenizing chamber at the outlet end of the reformer, from where it is conducted via the secondary section of the supply line to the said secondary gas burner, in which combustion of the syngas is effected, thereby releasing heat into the interior of the oxidation chamber.

[0041] Furthermore, in the process according to the invention, it is also envisaged that through a further step (viii), after establishing combustion of the synthesis gas supplied via the secondary section of the additional supply line into the second gas burner, a corresponding reduction in the quantity of natural gas supplied to the primary burner of the oxidation chamber is effected, thereby enabling the regular implementation of steps (i) to (v), including the previously described variants, within the parameters described above.

[0042] In a preferred embodiment of the process according to the invention, the mixture of steam and a hydrocarbon gas, preferably methane, is conducted through a catalyst assembly comprising a predetermined number of individual catalysts, which are arranged within each of the tubes at predetermined mutual distances, as described above. The catalyst preferably comprises a suitable metal selected from the group comprising nickel (Ni), cobalt (Co), copper (Cu), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), and platinum (Pt), and any combinations thereof. A suitable catalyst is selected depending on the type of fuel.

[0043] The invention will be described in further detail based on exemplary embodiments and figures, which show:

[0044] Figure 1 a schematically illustrated device known from the prior art for cleaning air contaminated with emissions originating from surface treatment technological processes, wherein such a device also carries out a purification process of the type known from the prior art Figure 2 an oxidation device for the cleaning of emissions from technological processes in a possible embodiment

[0045] Figure 3 an oxidation device in a possible embodiment, wherein such a device also carries out the air cleaning process according to the invention Figure 4 a reforming assembly of the device as shown in Figure 2 or 3 Figure 5 a partial longitudinal section of a flow tube of the reformer in the said reforming assembly

[0046] As shown in Figure 1, a known device for treating emissions originating from surface treatment technological processes comprises:

[0047] - a supply conduit 11, through which air contaminated with organic substances in a gaseous state flows into the device from a given source, for example from a paint shop or another similar chamber for carrying out surface treatment in an industrial process, wherein the temperature T1 of the contaminated air upon entering the supply conduit 11 is 100 to 400 °C, preferably at least about 200 °C;

[0048] - a heat exchanger 2 with a closed shell 20, designed as a sealed vessel of suitable volume, through which the said supply conduit 11 containing contaminated air extends, and which is surrounded by the said shell 20, wherein the heat exchanger 2 is adapted such that the contaminated air in the supply conduit 11 , while passing through the heat exchanger 2, is heated to a temperature T2 of 400 to 700 °C, preferably about 650 °C;

[0049] - an oxidation chamber 3 to which, after passing through the heat exchanger 2, the said supply conduit 11 containing contaminated air is connected via a sealed connection at its inlet opening 301 , thereby enabling the contaminated air supplied each time, after being correspondingly preheated to the aforementioned temperature T2 upon exiting the region of the said heat exchanger 2, to flow unhindered into the interior of the said oxidation chamber 3.

[0050] The oxidation chamber 3 of the device, as shown in Figure 1 , comprises a primary gas burner 31, which is supplied via a supply line 30 carrying fuel, namely natural gas, in particular natural gas, methane, biomethane, or mixtures thereof, wherein at the burner 31 the required amount of air with sufficient oxygen content is provided to enable efficient combustion of the natural gas. The burner 31 is adapted for combustion of the said gas in the interior of the oxidation chamber 3, in which, in this manner, a temperature T3 is achieved that is generally at least 820 °C, preferably at least 870 °C, at which practically complete oxidation of the organic impurities in a gaseous state, which were previously mixed with the contaminated air entering via the supply conduit 11 , takes place.

[0051] The oxidation chamber 3 is further provided with an outlet opening 302, to which a discharge conduit 12 is connected via a sealed connection, through which, from the reaction chamber 3, after oxidation of the gaseous organic substances previously mixed with the air, cleaned air exits together with combustion products in a gaseous state and a smaller fraction of combustion products in a solid state, the temperature of which at least approximately corresponds to the temperature T3 of the interior of the said oxidation chamber 3.

[0052] The discharge conduit 12 from the aforesaid outlet opening 302 of the oxidation chamber 3 extends to the aforesaid heat exchanger 2, such that the discharge conduit 12 is connected to the inlet opening 201 on one side of the shell 20 of the heat exchanger 2, through which cleaned hot air together with combustion products from the discharge conduit 12 enters the interior of the shell 20 of the heat exchanger 2, and to the outlet opening 202 on the opposite side of the shell 20, through which the cleaned hot air together with combustion products exits the shell 20 of the heat exchanger 2 and flows through the chimney, or similar outlet, into the atmosphere. Since within the shell 20 of the heat exchanger 2 there extends the aforesaid supply conduit 11 containing contaminated air, and since the said supply conduit 11 inside the shell 20 of the heat exchanger 2 is surrounded by the said hot cleaned air from the discharge conduit 12, the contaminated air in the supply conduit 11 , during its passage through the heat exchanger, as already explained, is heated to the desired temperature T2.

[0053] To the aforesaid discharge conduit 12, in the section between the reaction chamber 3 and the heat exchanger 2, a primary supply line 13 for supplying clean ambient air at room temperature To, up to 30 °C may optionally be connected, the said primary supply line 13 being adapted to add such an amount of clean ambient air to the cleaned hot air in the discharge conduit 12 that the temperature of the cleaned air in the discharge conduit 12, prior to entering the interior of the shell 20 of the heat exchanger 2, is reduced to a temperature T4 not exceeding 750 °C. In this way, the heat exchanger 2 can be substantially protected against thermal overload.

[0054] Also optionally, in the section between the heat exchanger 2 and the chimney, or similar outlet into the atmosphere, a secondary supply line 14 for supplying clean ambient air at room temperature To, up to 30 °C, may be connected to the said discharge conduit 12, the said secondary supply line 14 being adapted to add such an amount of clean ambient air to the cleaned hot air with temperature T4' exiting from the heat exchanger 2 into the discharge conduit 12, that the temperature of the cleaned air in the discharge conduit 12, prior to being discharged into the surrounding atmosphere through the filter 41 for removing solid particles from the air and into the chimney, or similar outlet, is reduced to a temperature T5, such that the cleaned air at temperature T5 has no significant adverse effects on the environment, or that such effects remain within acceptable limits.

[0055] The described device as shown in Figure 1 enables the implementation of an air cleaning process, wherein:

[0056] i. in the first step, air contaminated with organic impurities in a gaseous state, at a temperature T1 of 100 to 400 °C, preferably about 200 °C, is collected in the supply conduit 11;

[0057] ii. in the second step, the contaminated air is conducted through the heat exchanger 2 via the interior of the said supply conduit 11, wherein the contaminated air in the supply conduit 11 is heated to a temperature T2 of 400 to 700 °C, preferably about 650 °C;

[0058] iii. in the third step, the thus-preheated contaminated air is conducted via the supply conduit 11 into the interior of the oxidation chamber 3, where, at a temperature T3 of at least 870 °C, in the presence of a gas burner combusting natural gas, in particular natural gas, methane, biomethane, or mixtures thereof, it is subjected to thermal oxidation for a duration sufficient to achieve complete thermal oxidation of the organic impurities in a gaseous state present in the contaminated air from the supply conduit 11;

[0059] iv. in the fourth step, the cleaned hot air at temperature T3, which still at least approximately corresponds to the temperature in the interior of the oxidation chamber 3, is conducted to the heat exchanger 2, wherein a portion of the heat is transferred from the cleaned air at temperature T4 in the discharge conduit 12 to the contaminated air in the supply conduit 11 passing through the heat exchanger 2, such that the temperature T4' of the partially cooled clean air in the discharge conduit 12 after exiting the heat exchanger 2 is correspondingly reduced to a predetermined temperature T4';

[0060] v. in the fifth step, the cleaned air is conducted via the discharge conduit 12 to the filtration of mechanical particles through a filter 41 , after which it is discharged into the surrounding atmosphere around the chimney, or similar outlet, at a discharge temperature T5, which generally does not exceed 250 °C; whereby:

[0061] - in one variant of the process, in step iv, such an amount of clean ambient atmospheric air at room temperature To, up to 30 °C, is added to the cleaned hot air at temperature T3 in the discharge conduit 12 after exiting the oxidation chamber 3 and prior to entering the heat exchanger 2, that the temperature T4 of the air entering the heat exchanger 2 via the discharge conduit 12 does not exceed 750 °C;

[0062] - in a further variant of the process, in step v, either in combination with the preceding variant or independently thereof, such an amount of clean ambient atmospheric air at room temperature To, up to 30 °C, is added to the cleaned hot air at temperature T4' in the discharge conduit 12 after exiting the heat exchanger 2 and prior to filtration in the filter 41 and discharge into the surrounding atmosphere through the outlet 4, that the temperature T5 of the air exiting into the atmosphere via the discharge conduit 12, the filter 41, and the chimney, or similar outlet, does not exceed a predetermined temperature T5, which generally does not exceed 250 °C and at which the effects of the cleaned air released into the atmosphere from the discharge conduit 12 remain acceptable for the environment.

[0063] It must be understood that, for the uninterrupted course of thermal oxidation of harmful emissions of organic origin in the contaminated air, it is necessary to provide a relatively high temperature in the interior of the oxidation chamber, generally at least 820 °C, in most cases above 850 °C, and frequently even above 870 °C, and then to maintain this condition permanently, otherwise the chemical processes in the oxidation chamber will not be fully completed and the air will therefore be only partially cleaned. For the permanent maintenance of the required conditions in the interior of the oxidation chamber, it is therefore necessary to account for the corresponding consumption of natural gas, which is not only costly but also leads to other undesirable effects, such as substantial CO2 emissions and the environmental burden associated with this.

[0064] Embodiments of the device and process according to the invention are illustrated in Figures 2 to 5.

[0065] The oxidation device for the purification of emissions from technological processes, as illustrated in Figure 2, is designed such that at least thermochemical recuperation is carried out therein. The oxidation device comprises:

[0066] - an oxidation chamber 2 adapted for the oxidation of the said emissions, having an inlet opening connected to a supply conduit 1 for emissions, and an outlet opening through which cleaned emissions 1 A exit the oxidation chamber 2;

[0067] - a burner system 4 for raising the temperature of the emissions to the oxidation temperature thereby providing thermal energy wherein:

[0068] o there are at least two burners in the oxidation chamber 2, namely at least one first burner and at least one second burner; wherein a first conduit extends from outside the oxidation chamber to at least one first burner and supplies a hydrocarbon gas from an external source; and wherein a second conduit supplies steam and a hydrocarbon gas via the thermochemical recuperation system 5 to the second burner, or

[0069] o there is at least one burner in the oxidation chamber 2 to which a separate first conduit and second conduit are connected;

[0070] - there is a discharge line extending from the said outlet opening of the oxidation chamber 2 to the inlet opening of the thermochemical recuperation system 5; - there is a thermochemical recuperation system 5, which is at least partially mounted adjacent to the oxidation chamber 2 and utilizes the heat of the cleaned emissions 1 A exiting therefrom to modify the chemical composition and increase the calorific value of a hydrocarbon gas 7 before it reaches the burner, wherein the thermochemical recuperation system comprises:

[0071] o a preheater adapted to raise the temperature of a mixture of steam and a hydrocarbon gas to a temperature required for a stable steam reforming process, the preheater having a mixing chamber 6 connected at least to a supply of hydrocarbon gas 7 and to a steam supply 8 as a source of hydrogen and oxygen, and

[0072] o a reformer, which may be of any design, and is adapted for chemical catalytic reaction between the gas and the steam to optimize the process of the thermal oxidation of the emissions; wherein the reformer comprises at least one, and preferably several, tubes, which may have the same or different diameters; and wherein at least one catalyst, preferably several catalysts, is / are arranged inside the said tubes, the catalysts being disposed along the entire tube, along only one part of the tube, or in several separate sections of the tube, such that the gas mixture supplied from the preheater can come into contact with the catalyst,

[0073] o an outlet 9 from which the gas, which may contain H2, CO, and the like, output from the reformer is directed back into the oxidation chamber 2; - a discharge conduit leading from the thermochemical recuperation system to a chimney, or similar outlet, through which the cooled cleaned emissions 1B are discharged into the surrounding atmosphere.

[0074] The device shown in Figure 3 comprises an oxidation chamber 3, which is provided with an inlet opening 301 and an outlet opening 302, and with a gas burner 31 adapted for the combustion of natural gas, which is controllably supplied via a supply line 30 from a suitable source 301. The natural gas generally comprises non-liquefied natural gas from one of the pipelines, with an optional addition of biogas. The aforesaid device, according to the invention, further comprises a heat exchanger 2 with a shell 20 provided with an inlet opening 201 and an outlet opening 202, and also a supply conduit 11 which extends from a given source of emissions through the said heat exchanger 2 to the said inlet opening 301 of the oxidation chamber 3, and a discharge conduit 12 which extends from the said outlet opening 302 of the oxidation chambers to the inlet opening 201 in the shell 20 of the said heat exchanger 2 and from the outlet opening 202 to a filter 41 for removal of solid particles and a chimney, or similar outlet, for discharging the cleaned emissions into the surrounding atmosphere.

[0075] The device may also optionally comprise a primary supply line 13 of atmospheric air, which is connected to the aforesaid discharge conduit 12 in the section between the outlet opening 302 of the oxidation chamber 3 and the inlet opening 201 of the shell 20 of the heat exchanger 2, for the purpose of lowering the temperature of the cleaned emissions in the discharge conduit 12 with the addition of cold air to such a level that excessive thermal loads on the components and materials of the heat exchanger 2 are prevented.

[0076] In addition, such a device may optionally comprise a secondary supply line 14 of atmospheric air connected to the aforesaid discharge conduit 12 in the section between the outlet opening 202 of the shell 20 of the heat exchanger 2 and the said chimney, or similar outlet, for discharging cleaned emissions into the surrounding atmosphere, for the purpose of further lowering the temperature of the air exiting into the atmosphere to such a level that the cleaned emissions released into the environment produce practically no harmful effects.

[0077] In the context of solving the technical problem set out in the introduction, the device, according to the invention, further comprises a thermochemical recuperator 5, which comprises a shell 50 with an inlet opening 501 and an outlet opening 502. The thermochemical recuperator 5 is installed in the section between the outlet opening 302 of the oxidation chamber 3 and the inlet opening 201 of the heat exchanger 2, such that the aforesaid discharge conduit 12 extends from the outlet opening 302 of the oxidation chamber 3 through the inlet opening 501 of the shell 50 of the thermochemical recuperator 5, then through the interior thereof, and then through the outlet opening 502 of the shell 50 of the thermochemical recuperator 5 to the inlet opening 201 of the heat exchanger 2. The thermochemical recuperator 5 Fig. 4 comprises in the interior of its shell 50 a preheater 6 and a reformer 7 hydraulically connected in series with each other, each of which is formed as a plurality of tubes 600, 600', 600"; 700, 700', 700" arranged reasonably parallel to one another and hydraulically interconnected via a connecting chamber 670 at the outlet end of the preheater 6 and at the inlet end of the reformer 7. In this context, the preheater 6 is provided at its inlet end with a mixing chamber 601 to which the respective tubes 600, 600', 600" of the preheater 6 are individually connected, and at its outlet end with the connecting chamber 670 to which the respective tubes 700, 700', 700" at the inlet end of the reformer 7 are individually connected. At the outlet end of the reformer 7 these tubes converge individually into the homogenizing chamber 702. The terminology used is also visually explained by the arrows in Figures 2 to 4, which illustrate the direction of flow of the material particles. On the other side, a primary section 15' of a supply line 15, which is connected to a source 66 of a mixture of natural gas and water, is connected to the aforesaid mixing chamber 601 of the preheater 6 in the thermochemical recuperator 5, in addition to the aforesaid tubes 600, 600', 600" of the preheater 6. This is a predetermined or adjusted mixture in which the methane CF and water H2O contents are present in a molar ratio in the range of between 1 :2 and 1:1. The secondary section 15" of the aforesaid supply line 15 is hydraulically connected on one side to the homogenizing chamber 702 at the outlet end of the reformer 7, and on the other side to a secondary gas burner 8 installed in the oxidation chamber 3 alongside the primary gas burner 31 mentioned at the outset. The gas burner 8 is adapted for the combustion of synthesis gas, which will be explained in more detail hereinafter.

[0078] Inside each of the reformer’s 7 aforesaid tubes 700, 700', 700" a catalyst assembly 9 is provided Fig. 4, consisting of a predetermined number of individually arranged catalysts 900, 900', 900" placed in a predetermined manner, each of which is provided as a sleeve that loosely fits into the interior of the respective tube 700, 700', 700", is generally displaceable along the interior of the respective tube 700, 700', 700", and at the same time can be fixed in position at a predetermined distance L0, L1 , L2, L3 from the adjacent catalyst 900, 900', 900". Each sleeve is integrally formed and provided with a plurality of longitudinal through-passages 90, 90', 90", and consists of a predetermined material which, during operation of the device and the course of the chemical reactions therein, functions as a chemical catalyst. The diameter of each catalyst 900, 900', 900" is defined by the internal diameter of the respective tube 700, 700', 700" of the reformer 7, while the number and dimensions of the passages 90, 90', 90" are to be selected in such a way as to provide the largest possible surface area, whereby molecules of the aforesaid mixture of steam and methane can come into direct contact the surface of each individual catalyst 900, 900', 900" during passage. Empirical findings to date indicate that the operation of the device is sufficiently effective if each of the aforesaid catalysts 900, 900', 900" comprises nickel Ni, although further embodiments of the invention are certainly possible in which the catalyst comprises other suitable metals selected from the group comprising cobalt Co, copper Cu, molybdenum Mo, ruthenium Ru, rhodium Rh, and platinum Pt.

[0079] In one embodiment of the device according to the invention, it is provided that the mutual distances L0, L1 , L2, L3 between each pair of adjacent catalysts 900, 900', 900" in the interior of each of the tubes 700, 700', 700" of the reformer 7, viewed in the direction from the connecting chamber 670 at the inlet end of the reformer 7 toward the homogenizing chamber 702 at the outlet end of the reformer 7, are predetermined and constant.

[0080] In the reformer 7, the chemical conversion of the aforesaid mixture of steam H2O and methane into hydrogen H2 and carbon monoxide CO, i.e. so-called synthesis gas syngas, takes place. The chemical reactions themselves are known and are described in the technical literature, for example:

[0081] H.-W Haring ed., Industrial gases processing, Wiley-VCH Verlag GmbH and Co. Weinheim 2008, ali K. Liu, C. Song, and V. Subramani Eds., Hydrogen and syngas Production and Purification Technologies, John Wiley and Sons, Inc. Hoboken, New Jersey 2010.

[0082] Synthesis gas is usually obtained in suitable reactors and constitutes a gaseous mixture of hydrogen H2, carbon monoxide CO, and usually smaller amounts of carbon dioxide CO2, nitrogen N2, and methane CH4. Synthesis gas may be obtained from hydrocarbon-containing substances, for example from coal or biomass, but also from natural gas. However, the calorific value of synthesis gas is substantially higher than the calorific value of the natural gas from which it was produced.

[0083] Atypical reaction when reforming natural gas, for example with steam, which usually yields an H2 / CO ratio, is as follows:

[0084] CH4+ H2O CO + 3H2 The reaction proceeds stepwise and in the presence of the catalyst 900, 900', 900", which means that it continues until all molecules of the aforesaid mixture of steam and methane have, where possible, completed their reactions in contact with the catalyst 900, 900', 900".

[0085] For this very reason, a further variant of the device according to the invention is particularly advantageous, wherein the mutual distances L0, L1, L2, L3 between each pair of adjacent catalysts 900, 900', 900" in the interior of each of the tubes 700, 700', 700" of the reformer 7, viewed in the direction from the connecting chamber 670 at the inlet end of the reformer 7 toward the homogenizing chamber 702 at the outlet end of the reformer 7, are predetermined and decrease proportionally in the direction from the connecting chamber 670 at the inlet end of the reformer 7 toward the homogenizing chamber 702 at the outlet end of the reformer 7, wherein the ratio between each preceding mutual distance L3 / L2 and each subsequent mutual distance L2 / L1 between adjacent catalysts 900, 900', 900" is predetermined depending on the intended course of chemical reactions in the thermochemical recuperator 5 during operation of the device under given conditions. This means that by rearranging the catalysts 900, 900', 900" it is possible to optimize the operation of the device according to the invention, such that, in proximity to the initially more widely spaced catalysts 900, 900', 900", the majority of the molecules of the aforesaid steam mixture can react more or less unhindered, while the remaining molecules may gradually react somewhat later during passage of the substance through the more closely spaced catalysts 900, 900', 900". In this way, the efficiency of the operation of the device and of the process carried out therein can be substantially improved, as will be described in more detail hereinafter.

[0086] As shown in Figures 2 to 5, the device enables the implementation of a process for the cleaning of emissions from technological processes by means of the thermal oxidation of the said emissions, which can be suitably explained in connection with the aforesaid drawings and the arrows indicated therein, which denote the direction of movement of the material particles.

[0087] When carrying out the process in the aforesaid device, in general: - i in the first step, emissions containing organic impurities in the gaseous state at a temperature T1 of 100-400 °C, preferably approximately 200 °C, are collected in the supply conduit 11 ;

[0088] - ii in the second step, the emissions are conducted through the heat exchanger 2 via the said supply conduit 11 , whereby the emissions in the supply conduit 11 are heated to a temperature T2 of 400-700 °C, preferably approximately 650 °C;

[0089] - iii in the third step, the thus-heated emissions are conducted via the supply conduit 11 into the interior of the oxidation chamber 3, where, at a temperature T3 which is usually at least 820 °C and preferably at least 870 °C, and in the presence of at least one gas burner 31 combusting a fuel gas, in particular natural gas or methane or biomethane or mixtures thereof, the emissions are subjected to thermal oxidation for a duration sufficient to effect complete thermal oxidation of the organic impurities present in the emissions in a gaseous state;

[0090] - iv in the fourth step, the cleaned hot emissions having a temperature T3', which at least approximately corresponds to the temperature inside the oxidation chamber 3, are directed toward the heat exchanger 2, wherein heat is transferred from the cleaned emissions at a temperature T4 in the discharge conduit 12 to the fresh inflowing emissions in the supply conduit 11 passing through the heat exchanger 2, such that the temperature of the cleaned emissions in the discharge conduit 12, partially cooled in this manner after exiting the heat exchanger 2, is accordingly reduced to a predetermined temperature T4';

[0091] - v in the fifth step, the cleaned emissions are conducted via the discharge conduit 12 to the filtration of mechanical particles in a filter 41 , after which they are discharged at a temperature T5, not exceeding 250 °C, through a chimney, or similar outlet, into the surrounding atmosphere.

[0092] In one variant of such a process, in step iv, a quantity of ambient atmospheric air at room temperature To, of up to 30 °C, is added to the cleaned emissions having a temperature T3' in the discharge conduit 12 after exiting the oxidation chamber 3 and before entering the heat exchanger 2, such that the temperature T4 of the air entering the heat exchanger 2 via the discharge conduit 12 does not exceed 750 °C. In a further variant of such a process, in step v, either in combination with the preceding variant of the aforesaid process or independently thereof, a quantity of clean ambient atmospheric air at room temperature To, of up to 30 °C, is added to the hot cleaned emissions having a temperature T4' in the discharge conduit 12 after exiting the heat exchanger 2 and before filtration in the filter 41 and discharge into the surrounding atmosphere through the chimney 40, or similar outlet, such that the temperature T5 of the cleaned emissions exiting into the atmosphere through the discharge conduit 12, the filter 41, and the chimney 40, or similar outlet, does not exceed a predetermined temperature T5, which generally does not exceed 250 °C and at which the impact of the cleaned emissions released into the atmosphere from the discharge conduit 12 remains within environmentally acceptable limits.

[0093] In the context of solving the technical problem set out in the introduction, the process according to the invention is characterized in that: vi in the sixth step, after the process has been established in accordance with the aforesaid steps i to v and / or at least one of the two further variants of the process according to steps i to v, it is ensured that the discharge conduit 12, carrying the cleaned emissions at a temperature T3', which upon exiting the oxidation chamber 3 through the outlet opening 302 amounts to at least 820-850 °C, is guided, in the section between the oxidation chamber 3 and the aforesaid heat exchanger 2, through a thermochemical recuperator 5, consisting of a preheater 6 and a reformer 7, in such a manner that the cleaned emissions in the discharge conduit 12 are directed into the interior of the shell 50 of the thermochemical recuperator 5, so that the hot cleaned emissions from the discharge conduit 12 first flow through the reformer 7, namely through the gaps between the outer surfaces of the tubes 700, 700', 700" of the reformer 7 arranged side by side, and directly after passing through the reformer 7 then flow through the preheater 6, namely through the gaps between the outer surfaces of the tubes 600, 600', 600" of the preheater 6, whereupon the cleaned emissions, having a temperature T4", upon exiting the shell 50 of the thermochemical recuperator 5, are again conducted via the discharge conduit 12, in accordance with the previously described fourth step iv, into the heat exchanger 2, and then, in accordance with the previously described fifth step v, into the surrounding atmosphere. At the same time, in the process according to the invention, in a further step vii, it is ensured that:

[0094] - a source 66 of water H2O, which may generally be in liquid or gaseous state, and natural gas, namely natural gas or biogas with a sufficient methane CH4 content, is provided;

[0095] - an additional supply line 15 is provided, the primary section 15' of which runs from the said source 66 of water H2O and natural gas with sufficient methane CH4 content to the inlet of the aforesaid thermochemical recuperator 5, while the secondary section 15" of the said additional supply line 15 leads from the aforesaid thermochemical recuperator 5 to the aforesaid secondary gas burner 8, which is installed in the oxidation chamber 3 in addition to the already mentioned gas burner 3.

[0096] The aforesaid secondary gas burner 8 is adapted for the combustion of synthesis gas. The mixture of water H2O and natural gas with methane CH4 content from the aforesaid source 66 is conducted, via the primary section 15' of the additional supply line 15, into the mixing chamber 601, which serves as the inlet to the aforesaid thermochemical recuperator 5, such that in the mixing chamber 601 a mixture of water H2O and methane CH4 is formed in a molar ratio of 1 :1. The thus-obtained mixture of water H2O and methane-containing gas CH4from the aforesaid mixing chamber 601 is then conducted through the preheater 6 of the aforesaid thermochemical recuperator 5, namely through the interior of the tubes 600, 600', 600" of the preheater 6, whereby the said gaseous mixture of steam and methane-containing gas CH4 is heated to a temperature T6 of at least 750 °C. Thereafter, the thus-heated gaseous mixture is conducted, via the connecting chamber 670, into the interior of the tubes 700, 700', 700" of the reformer 7, where, in the presence of catalysts 900, 900', 900", synthesis gas syngas is formed, namely a mixture of hydrogen H2 and carbon monoxide CO in a ratio of approximately 75% H2 and 25% CO, which is collected in the homogenizing chamber 702 at the outlet end of the reformer 7.

[0097] The synthesis gas is conducted from the homogenizing chamber 702 at the outlet end of the reformer 7, via the secondary section 15" of the supply line 15, to the aforesaid secondary gas burner 8, in which it is combusted, and thereby releases heat into the interior of the oxidation chamber 3. Since, however, the calorific value of the synthesis gas is substantially higher than the calorific value of the natural gas combusted in the primary burner 31, the process according to the invention further provides for an additional measure, which dictates that:

[0098] in step viii, after initiation of the combustion of the syngas flowing through the secondary section 15" of the additional supply conduit 15 into the secondary gas burner 8, a corresponding reduction in the amount of natural gas supplied to the primary burner 31 of the oxidation chamber 3 is ensured, thereby enabling the establishment of regular execution of steps i to v, including the previously described variants, within the framework of the previously defined parameters. By this measure, during prolonged operation of the device and implementation of the emission purification process, the consumption of natural gas can be drastically reduced, which results in a significant reduction in operating costs as well as in a significant reduction in the release of undesirable CO2 emissions and other combustion products into the environment.

[0099] In a preferred embodiment of the process according to the invention, the mixture of steam and methane-comprising gas CH4, heated to a temperature T6 of at least 750 °C, is conducted through the interior of the tubes 700, 700', 700" of the reformer 7 via a catalyst assembly 9, which consists of a predetermined number of individual catalysts 900, 900', 900". These are arranged inside each of the aforesaid tubes 700, 700', 700" at predetermined mutual distances L0, L1 , L2, L3, and each is provided with a plurality of through-passages 90, 90', 90".

[0100] In a preferred embodiment of the process according to the invention, catalysts 900, 900', 900" are used, each of which comprises Ni or any other suitable metal, such as cobalt Co, copper Cu, molybdenum Mo, ruthenium Ru, rhodium Rh, or platinum Pt. In one variant of the process according to the invention, the mutual distances L0, L1, L2, L3 between the pairs of adjacent catalysts 900, 900', 900" in the interiors of the tubes 700, 700', 700" of the reformer 7, in the direction between the connecting chamber 670 at the inlet end of the reformer 7 and the homogenizing chamber 702 at the outlet end of the reformer 7, toward the secondary section 15" of the additional supply line 15, are adjusted in such a manner that the distances LO between the pairs of adjacent catalysts 900, 900', 900" are equal.

[0101] For the reasons explained above, a preferred embodiment of the process according to the invention may be one in which the mutual distances L0, L1 , L2, L3 between the pairs of adjacent catalysts 900, 900', 900" in the interior of the tubes 700, 700', 700" of the reformer 7, in the direction between the connecting chamber 670 at the inlet end of the reformer 7 and the homogenizing chamber 702 at the outlet end of the reformer 7, toward the secondary section 15" of the additional supply line 15, are adjusted in such a manner that the mutual distances L1, L2, L3 between the pairs of adjacent catalysts 900, 900', 900" proportionally decrease in the direction from the connecting chamber 670 toward the homogenizing chamber 702, wherein the ratio between each preceding mutual distance L3 / L2 and each subsequent mutual distance L2 / L1 between adjacent catalysts 900, 900', 900" is predetermined depending on the expected course of chemical reactions in the thermochemical recuperator 5 during implementation of the process.

Claims

Patent claims1. An oxidation device for cleaning emissions from technological processes, characterized in that thermochemical recuperation occurs in the device, wherein the oxidation device comprises:- an oxidation chamber (2) configured for the oxidation of the said emissions, with an inlet opening connected to a supply (1) of emissions and an outlet opening through which cleaned emissions leave the oxidation chamber (2),- a burner system (4) for raising the temperature of the emissions to the oxidation temperature, wherein:o there are at least two burners in the oxidation chamber (2), namely at least one first burner and at least one second burner; wherein a first conduit extends from outside the oxidation chamber (2) to at least one first burner and is arranged to supply a hydrocarbon gas from an external source; and wherein a second conduit is arranged to supply and steam and a hydrocarbon gas to the second burner via a thermochemical recuperation system, oro there is at least one burner in the oxidation chamber (2), to which a separate first conduit and second conduit are connected, - a discharge line extending from the said outlet opening of the oxidation chamber (2) to the inlet opening of the thermochemical recuperation system (5),- a thermochemical recuperation system (5), which is at least partially built adjacent to the oxidation chamber (2) and utilizes the heat of the exiting cleaned emissions to modify the chemical composition and increase the calorific value of the hydrocarbon gas before it reaches the burner; wherein the thermochemical recuperation system (5) comprises:o a preheater arranged to raise the temperature of the mixture of steam and hydrocarbon gas to the temperature required for a stable steam reforming process, wherein the preheater comprises a mixing chamber (6) connected to at least the hydrocarbon gas supply (7) and the steam supply (8) as a source of hydrogen and oxygen, ando a reformer, which may be designed in any suitable manner, and is configured for chemical catalytic reaction between the gas and the steam to optimize the process of the thermal oxidation of the emissions; wherein the reformer comprises at least one, preferably more, tubes, which may have the same or different diameters; and wherein at least one catalyst, preferably more, is / are arranged inside the said tube(s), the catalyst(s) being disposed along the entire tube, along only one part of the tube, or in several separate sections of the tube, such that the gas mixture supplied from the preheater can come into contact with the catalyst, o an outlet (9) through which the gas output from the reformer is directed back into the oxidation chamber (2),- a discharge conduit leading from the thermochemical recuperation system to a chimney or similar outlet for discharging the cleaned emissions into the surrounding atmosphere.

2. The oxidation device for cleaning emissions from technological processes according to claim 1 , wherein the temperature needed for a stable process of steam reforming depends on the selected catalyst and is usually at least 700 °C.

3. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the burner system (4) comprises a supply of air or oxygen.

4. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the preheater comprises a mixing chamber (6), which is additionally connected to a supply of flue gas and / or CO and / or oxygen and / or air.

5. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the catalyst is arranged along the whole tube, in one part of the tube or in several separate parts of the tube.

6. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the reformer further comprises at least one spacer to delimit two parts with catalyst.

7. The oxidation device for cleaning emissions from technological processes according to the preceding claim, wherein the spacer is a cylindrical element with through holes, a torus or any other element with at least one through opening so that gases may move from one part with a catalyst to the second part with the catalyst.

8. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the distances between two adjacent catalysts are equal.

9. The oxidation device for cleaning emissions from technological processes according to any claim from 1 to 7, wherein the distances between two adjacent catalysts are different.

10. The oxidation device for cleaning emissions from technological processes according to claim 9, wherein the distances from the connecting chamber to the homogenization chamber are proportionally decreasing.

11. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the reformer further comprises chambers, which separate and combine flows from individual tubes of the reformer.

12. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the catalyst comprises a suitable metal selected in the group comprising nickel (Ni), cobalt (Co), copper (Cu), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), and platinum (Pt), or any combination thereof.

13. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the gas selected in the group of hydrocarbons, CH4.

14. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein to the mixing chamber of the preheater a section of the supply conduit, which is connected to a source of natural gas and a source of water, wherein preferably the natural gas and water are mixed in a molar ratio from 1 :2 to 1 :1 , preferably towards 1:1.

15. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein a cooling system is provided between the discharge conduit and the thermochemical system (5), which, if necessary, is arranged to decrease the temperature of the cleaned emissions in order to prevent catalyst degradation.

16. The oxidation device for cleaning emissions from technological processes according to any of the preceding claims, wherein the device comprises a heat exchanger installed downstream of the thermochemical recuperation system (5), wherein at least a portion of the cleaned emissions is fed into the heat exchanger, in which the next portion of the heat of the cleaned emissions is recovered, wherein at least a portion of the heat is transferred to the input stream of emissions from technological processes that are fed into the oxidation chamber (2).

17. A method for cleaning emissions from technological processes using thermochemical recuperation comprising the following steps:i. collecting emissions, which generally have a temperature between 100 and 400 °C, preferably about 200 °C, in a supply conduit;ii. directing the collected emissions from the supply conduit into the heat exchanger, wherein the emissions in the said heat exchanger are heated to a temperature preferably between 400 and 700 °C, more preferably about 650 °C;iii. directing the heated emissions into the interior of the oxidation chamber, wherein, at a temperature generally of at least 820 °C, preferably at least 870 °C, in the presence of at least one gas burner combusting a carbon- containing gas, in particular natural gas or methane or biomethane or mixtures thereof, the emissions are subjected to thermal oxidation for a duration sufficient to achieve complete thermal oxidation of the organic impurities contained in the emissions;iv. directing the oxidized emissions to the heat exchanger, where they transfer heat to fresh emissions entering the process and passing through the heat exchanger in step ii, such that the temperature of the oxidized emissions in the discharge line, i.e. after exiting the heat exchanger, is reduced;v. directing the cooled emissions from the preceding step through a discharge conduit, optionally to filtration of mechanical particles in a filter, after which the emissions, at a temperature generally not exceeding 250 °C, are discharged into the surrounding atmosphere via a chimney or similar outlet, characterized in that the process comprisesvi. a sixth step, after establishing the process according to the above-mentioned steps i) to v) and / or at least one of the two further variants of the process according to steps i) to v), it is ensured that the cleaned emissions, which upon exiting the oxidation chamber through the outlet opening have a temperature of preferably at least 820 to 850 °C, are directed, in the section between the oxidation chamber and the above-mentioned heat exchanger, also through the thermochemical recuperator as described above, in such a manner that the emissions cleaned of organic impurities are directed from the discharge conduit into the interior of the thermochemical recuperator, such that the hot cleaned emissions from the discharge conduit first flow through the reformer, preferably through the gaps between the outer surfaces of reformer tubes arranged side by side, and, immediately after passing through the reformer, through the preheater, preferably through the gaps between the outer surfaces of preheater tubes arranged side by side, after which the cleaned emissions, upon exiting the thermochemical recuperator, are again conducted via the discharge conduit, in accordancewith the previously described fourth step (iv), into the heat exchanger and, in accordance with the previously described fifth step (v), into the surrounding atmosphere.

18. The method according to claim 17, wherein the following is further performed:- supplying water and a hydrocarbon gas, preferably natural gas, typically natural gas or biogas with a sufficient methane content,- leading the water and hydrocarbon gas into the mixing chamber, which represent an entry into the thermochemical recuperator, such that in the mixing chamber a mixture of water and gas, preferably methane, is formed in a molar ratio from 1:2 to 1:1, after which the thus-obtained mixture of water and methane-comprising gas is led from the said mixing chamber through the preheater of the said thermochemical recuperator, namely through the interior of the preheater tubes, wherein the said gaseous mixture of steam and methane-comprising gas is heated to a temperature of at least 750 °C, after which the thus-heated gaseous mixture is led via the connecting chamber into the interior of the reformer tubes, where, in the presence of catalysts, synthesis gas (syngas) is formed, i.e. a mixture of hydrogen and carbon monoxide, which is collected in a homogenizing chamber at the outlet end of the reformer, from where it is conducted via the secondary section of the supply line to the said secondary gas burner, in which combustion of the syngas is effected, thereby releasing heat into the interior of the oxidation chamber.

19. The method according to claim 17 or 18, wherein an amount of clean surrounding air at room temperature up to 30 °C is added to the in step v) cleaned emissions in the with a particular temperature in the discharge conduit after exiting the oxidation chamber and before entering into the heat exchanger, so that the temperature of the air entering the heat exchanger from the discharge unit does not exceed the allowed temperature of the heat exchanger, wherein it usually does not exceed 750 °C.

20. The method according to any claim from 17 to 19, wherein an amount of clean surrounding air at room temperature up to 30 °C is added to the in step v) cleaned emissions in the discharge conduit after exiting the heat exchanger and before filtration in the filter and release into the surrounding atmosphere through a chimney or a similar discharge, so that the temperature in the discharge conduit through the filter and the chimney or a similar discharge does not exceed a pre-defined temperature, which is usually up to 250 °C and at which the effects of so released cleaned emissions are acceptable.

21. Use of the device or the method according to any of the preceding claims, for recuperation of energy during purification of discharges from technological processes comprising volatile emissions, organic and inorganic impurities and / or other components in a gaseous state.

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