Apparatus for calcination of fine quarry residues using ceramic modules

Abstract

The invention relates to an apparatus 100 for calcining fine quarry residues. The apparatus comprises an adiabatic tube 101 containing a ceramic calcination tube 102, and a cavity 1012 is defined between the two tubes. The adiabatic tube hosts the combustion of a flow of fuel gas 21 with a flow of oxygen 160. The ceramic tube receives fine carbonate 110, hosts in its inside the calcination reactions CaCO3 — ► CaO + CO2 and / or MgCO3 — ► MgO + CO2 and releases oxide 630 and fossil CO2 140. The apparatus also comprises electrical resistors 107 in the cavity that generate at least part of the heat necessary for the calcination reaction. The ceramic tube is made up of modules 105 and comprises slits 106 for the escape of fossil CO2 towards the cavity. The ceramic tube has a passage area between 0.01 m2 and 1.00 m2 and a length between 5 m and 100 m. The adiabatic tube receives the fossil CO2 and releases at its output a single flow of high- temperature exhaust gas 170 comprising the fossil CO2 and the gas produced by the combustion of the fuel gas through the oxygen.

Description

DESCRIPTIONAPPARATUS FOR CALCINATION OF FINE QUARRY RESIDUES USING CERAMIC MODULES*******

[0001] The present invention relates to an apparatus for calcination of fine quarry residues through the use of ceramic modules.

[0002] The effects of so-called “greenhouse gases” on the climate have long been known, especially the correlation between the concentration of CO2 (carbon dioxide) in the atmosphere and global warming.

[0003] The efforts of the scientific community and world politics in recent years have been concentrated on trying to counteract the increase in greenhouse gas emissions into the atmosphere, in order to avoid the phenomenon of global warming, i.e. the rise in the average temperature at a global level.

[0004] As is well known, a number of initiatives have been promoted at international level to limit CO2 emissions into the atmosphere: the Kyoto Protocol in 1997 and the Paris Agreement in 2015, among others, are worth mentioning.

[0005] The forms identified by the scientific community to avoid global warming are many and substantially concern the decrease in the use of fossil fuels such as coal, oil and natural gas favouring the development of renewable energies such as hydraulic, wind, solar energy, from biomass and of zero-emission fuels such as hydrogen or ammonia.

[0006] In addition, many efforts of the international community are focused on improving the efficiency of energy use, such as lighting with low-consumption light bulbs, transport with new generations of high-efficiency engines and, in the field of power generation, replacing old, inefficient coal- or oil-fired power stations with new combined-cycle gas turbine and steam turbine plants with energy efficiencies approaching 60%.

[0007] In many states, such as the European Union, stringent limits on CO2 emissions have been introduced with fines for offenders.

[0008] In a manner known per se, the lime sector is subject to stringent emission rules and has sought to optimise production processes, for example by replacing fossil fuels, such as natural gas, with biomass.

[0009] In a manner known per se, many companies also belonging to other production sectors have begun to use biomass to replace fossil fuels in order to reduce emissions.

[0010] The increase in biomass consumption has led to an increase in the cost of biomass itself and therefore an increase in the cost of the final products such as calcium oxide and calcium hydroxide.

[0011] In a manner known per se, almost all lime kilns on the market are vertical single shaft or double shaft regenerative or rotary kilns.

[0012] In a manner known per se, vertical kilns have a higher efficiency and lower maintenance than rotary kilns and have therefore been widely adopted in demanding, consumption-conscious markets such as the European market.

[0013] In a manner known per se, both vertical and rotary kilns are direct-fired kilns in which the combustion products of the fuel used come into direct contact with the lime.

[0014] Generally, in direct-fired kilns, the lime is contaminated by sulphur, chlorine, any heavy metals present in the fuel and ash.

[0015] The indirect-fired kilns, in which lime does not come into contact with combustion products, being less efficient, more expensive and unsuitable for large productions, are used only for the production of extremely pure lime and for laboratory plants.

[0016] In a manner known per se, the vertical kilns use large-sized pieces of ore, from 50 mm to 150 mm while the ideal size for rotary kilns is from 10 mm to 50 mm.

[0017] In a manner known per se, in the limestone production process necessary for the production of lime, between 25% and 50% of limestone is produced whose dimensions are too small to be used in the lime kilns: this material is generically referred to as “fine quarry residues” or “fine quarry materials”.

[0018] In a manner known per se, fine quarry residues generally have no profitable commercial outlets and are therefore accumulated in the quarries themselves downstream of the limestone crushing and screening processes to prepare material for use in lime kilns.

[0019] In a manner known per se, lime companies are looking for technologies to be able to reduce lime production costs to compensate for the increase in CO2 emission costs.

[0020] One of the most significant costs incurred by lime companies is that of using high quality biomass, i.e. virgin biomass with low ash.

[0021] A second major cost incurred by lime companies is that of not being able to use fine quarry residues to optimise the cost for extracting limestone from quarries.

[0022] The task of the present invention is to make available an apparatus and a method that can allow the calcination of fine quarry residues in an indirect way by also using gas from low-quality biomass gasification or waste with lower costs than known technologies.

[0023] This aim and these tasks are achieved by means of an apparatus and a method for calcination of fine quarry residues respectively according to claim 1. Other advantageous features are reported in the dependent claims.

[0024] In order to better understand the invention and appreciate its advantages, some exemplary and non-limiting embodiments thereof are described below, with reference to the attached drawings, in which:- figure 1 is a schematic view of an apparatus for calcining fine quarry residues according to the invention;- figure 2 is a schematic view of an apparatus for calcining fine quarry residues according to the invention;- figures 3 are schematic views of a ceramic material module according to the invention;- figures 4 are schematic views of a ceramic material module according to the invention;- figures 5 are schematic views of the ceramic calcination tube formed by different ceramic material modules according to the invention.

[0025] In the description, reference will also be made to the “fuel gas”, meaning thereby a gas containing predominantly, CH4, CO, H2, propane, butane, in any proportion at the gaseous state and other substances, including N2, Ar, O2, HC (hydrocarbons), HCO (oxygenated hydrocarbons), and H2O with calorific value LHV (Low Heating Value) greater than 4Mj / Nm3. Fuel gases also include syngas from the gasification or pyrolysis of biomass, waste or coal.

[0026] In the description, reference will also be made to “oxygen”, meaning thereby a gas mixture containing mainly oxygen and other substances, including N2 and H2O inany proportion, while when referring to the chemical compound O2 only in the description, O2 will be used. Atmospheric air falls under the definition of oxygen as a special case.

[0027] In the description, reference will also be made to “CO2” meaning thereby the chemical compound CO2 (carbon dioxide).

[0028] In the description, reference will also be made to “fossil carbon dioxide” or “fossil CO2”, meaning thereby a gas containing mainly CO2, and possibly other substances, including N2, O2, H2O, Ar, produced by the calcination of fine carbonate according to the known chemical reaction:CaCOs CaO + CO2.

[0029] In the description, reference will be made to the “exhaust gas” meaning thereby the gas produced by the combustion of the fuel gas made up mainly by CO2, H2O, O2 and N2 and with almost zero calorific value, possibly supplemented with the fossil carbon dioxide from the fine carbonate calcination process and the water vapour fed to the cavity of the indirect calciner.

[0030] In the description, reference will also be made to “high temperature”, meaning thereby temperatures between 500 °C and 1,500 °C, preferably between 500 °C and 1,200 °C.

[0031] In the description, reference will also be made to “low temperature”, meaning thereby temperatures between 0 °C and 500 °C, preferably between 80 °C and 400 °C.

[0032] In the description, reference will also be made to the “atmosphere”, meaning thereby any place in contact with atmospheric air.

[0033] In the description, reference will also be made to the “controlled atmosphere”, meaning thereby any place not in contact with the atmospheric air and where the composition of the gases and their pressure is defined by the process requirements.

[0034] In the description, reference will also be made to “fine carbonate” meaning any calcareous or dolomitic sedimentary rock such as calcite, aragonite, dolomite, siderite, magnesite, marble, but also any other carbonate material such as shells or corals with dimensions between 0.001 mm and 10 mm, preferably between 0.1 mm and 5 mm.

[0035] In the description, reference will also be made to the “indirect calciner” meaning any controlled atmosphere system, in itself known, capable of calcining fine carbonate according to the reactionsCaCOs CaO + CO2 (+183 kj / mol) orMgCOs MgO + CO2 (+118 kj / mol).The calcination process, known per se, takes place at temperatures preferably between 500 °C and 1 ,300 °C depending on the composition of the controlled atmosphere and the pressure present and is an endothermic process in which the energy necessary for calcination is at least partially given by the combustion of the fuel gas which takes place in a combustion chamber separated from the calcination chamber. The indirect controlled-atmosphere calciner does not allow direct contact of the calcination zone with ambient air or with combustion gas while it allows the flushing of the calcination zone possibly with inert gases or water vapour or the unidirectional passage of fossil carbon dioxide towards the combustion chamber where it mixes with the exhaust gases produced by the combustion of the fuel gas.

[0036] In the description, reference will also be made to the “adiabatic tube”, meaning thereby a closed hollow solid of variable section thermally insulated with respect to the atmosphere.

[0037] In the description, reference will also be made to the “ceramic tube”, meaning thereby a closed hollow solid of variable section built with ceramic material.

[0038] In the description, reference will be made to the “hollow profile”, meaning thereby a tube or profile with a cross-section in which the interior is empty. In the description, reference will also be made to the “passage area”, meaning thereby the internal transverse surface of the ceramic tube through which the fine carbonate can flow.

[0039] In the description, reference will be made to the “rectangular hollow section” or “RHS”, meaning thereby a tube or profile with a rectangular-shaped cross-section in which four sides form the perimeter of the rectangle, with generally rounded corners and in which the interior is empty.

[0040] In the description, reference will be made to the “slits”, meaning thereby the openings made in the walls of the ceramic calcination tube or of the ceramic material module: these openings can be holes or slots.

[0041] In the description, reference will also be made to the “oxide”, meaning thereby the calcination product formed mainly by calcium oxide CaO or magnesium oxide MgO and to a lesser extent by other materials (impurities) present in the carbonate rock with which the calciner is fed.

[0042] In the description, reference will also be made to the “hydroxide” meaning thereby the product of the hydration of calcium oxide Ca(0H)2 and / or magnesium oxide Mg(OH)2 and to a lesser extent from other materials (impurities) possibly present in the fine carbonate that is fed to the calciner.

[0043] In the description, reference will also be made to the “ceramic material” meaning thereby an inorganic, non-metallic material, which is usually produced through a sintering or heat treatment process such as alumina (AI2O3), zirconia (ZrO2), magnesia (MgO), silicon carbide (SiC), boron carbide (B4C), silicon nitride (Si3N4), aluminium nitride (AIN), kaolinite and mullite.

[0044] In the description, the comma will be used as a thousands separator and the dot as a decimal separator.

[0045] In the attached figures, reference 100 indicates as a whole the apparatus for calcining fine quarry residues according to the invention.

[0046] A first aspect of the invention relates to an apparatus for calcining fine quarry residues 100. The apparatus comprises an adiabatic tube 101 and a ceramic calcination tube 102, wherein:- the adiabatic tube 101 contains the ceramic calcination tube 102;- a cavity 1012 is defined between the adiabatic tube 101 and the ceramic calcination tube 102;- the adiabatic tube 101 comprises an inlet for the fuel gas 21, and an inlet for oxygen 160, and is configured to allow the combustion of a flow of fuel gas 21 with a flow of oxygen 160;- the ceramic calcination tube 102 is adapted to receive at its input a flow of fine carbonate 110, for the calcination reactions to take place inside itCaCO3— CaO + CO2and / orMgCO3- MgO + CO2and to release at its output a flow of oxide 630 and a flow of fossil CO2 140; and - the apparatus 100 comprises electrical resistors 107 positioned in the cavity 1012 and adapted to generate at least part of the heat necessary for the calcination reaction of the fine carbonate inside the ceramic calcination tube 102.The ceramic calcination tube 102:- is made up of ceramic material modules 105;- comprises slits 106 for the escape of the flow of fossil CO2 140 produced by the calcination;- allows the passage of the flow of fossil CO2 140 generated by the calcination of the fine carbonate from the inside of the ceramic material modules 105 through the slits 106 towards the cavity 1012;- has a passage area between 0.01 m2and 1.00 m2; and- has a length between 5 m and 100 m.The adiabatic tube 101 is adapted to receive the flow of fossil CO2 140 and to release at its output a single flow of high-temperature exhaust gas 170 comprising the fossil CO2 140 and the gas produced by the combustion of the fuel gas 21 through the oxygen 160.

[0047] Preferably, each ceramic material module 105 is a hollow profile and has one or more of the following characteristics:- has a passage area between 0.01 m2and 1.00 m2;- has a height 502 less than 1 ,000 mm;- has a width 503 less than 500 mm;- has a length 501 less than 2,000 mm;- has a wall thickness 506 less than 50 mm;- has slits 106 for the escape of the flow of fossil CO2 140 produced by the calcination; - is able to withstand temperatures above 1 ,000 °C;- has a heat transmission coefficient greater than 30 w / m / °C.

[0048] Preferably each ceramic material module 105 is a rectangular-shaped profile, for example of the RHS (Rectangular Hollow Section) type.

[0049] As already mentioned, the apparatus for calcining fine quarry residues 100 comprises electrical resistors 107 positioned in the cavity 1012 and adapted to generate at least part of the heat necessary for the calcination reaction of the fine carbonate inside the ceramic calcination tube 102. Preferably, the apparatus 100 of the invention is configured in such a way that the heat necessary for the calcination reaction of the fine carbonate inside the ceramic calcination tube 102 is provided in part by the electrical resistors 107 and in part by the combustion of the fuel gas 21.

[0050] The percentage of heat provided by the resistors 107 and the percentage provided by the combustion of the fuel gas 21 may vary in the different embodiments to meet specific needs.

[0051] In accordance with some embodiments, in the apparatus for calcining fine quarry residues 100 the ceramic modules 105 form slits 106 for the escape of fossil CO2 140 produced by the calcination when coupled with adjacent ceramic material modules 105. In accordance with other embodiments, the slits 106 for the escape of the flow of fossil CO2 140 are defined in the walls of the ceramic material modules 105 (see figures 3).

[0052] In accordance with some embodiments, the adiabatic tube 101 further comprises an inlet for a flow of water vapour 161 to lower the partial pressure of the CO2 in the cavity 1012.

[0053] In accordance with some embodiments and with reference to figure 2, the apparatus for calcining fine quarry residues 100 further comprises, downstream of the ceramic calcination tube 102, a hydrator 200. The hydrator 200 comprises:- an inlet for a flow of water 201 ;- an inlet for at least a part of the flow of oxide 630 exiting the ceramic calcination tube 102.

[0054] The hydrator 200 is configured to react water 201 with oxide 630 according to at least one of the reactions:CaO + H2O Ca(OH)2MgO + H2O Mg(OH)2and to release a flow of hydroxide 230 and a flow of water vapour 161. Preferably the flow of vapour 161 is fed at least in part to the cavity 1012 to lower the partial pressure of the CO2.

[0055] Referring to figures 1 and 2, the apparatus for calcining fine quarry residues 100 is fed with the flow of fine carbonate 110, the flow of fuel gas 21 , the flow of oxygen 160, and separately releases at least one flow of oxide 630 and the flow of high-temperature exhaust gas 170.

[0056] In a manner known per se, the calcination of the flow of fine carbonate 110 takes place according to the reaction CaCO3(s)CaO(s) + CO2(g), where Ca can be replaced by Mg if present in the flow of fine carbonate 110, at temperatures between about 500° (MgCOs) and 1300 °C (CaCOs) and at intermediate values depending on the chemical composition of the flow of fine carbonate 110 if it is a dolomite CaMg(COs)2 and on the chemical composition and pressure of the controlled atmosphere in the apparatus for calcining fine quarry residues 100.

[0057] In a manner known per se, the calcination reaction is an endothermic reaction requiring 118 KJ / mol of heat in the case of calcination of MgCOs and 183 KJ / mol in the case of CaCOs.

[0058] The flow of fossil CO2140 produced by indirect calcination of fine carbonate is a gas formed by CO2 and traces of gases such as N2 and O2 possibly entered with the flow of fine carbonate 110 into the apparatus for calcining fine quarry residues 100 or gases intentionally fed to the apparatus for calcining fine quarry residues 100 to improve process conditions as in the case of water vapour 161.

[0059] The flow of fine carbonate 110 fed to the apparatus for calcining fine quarry residues 100 is formed by small-sized particles, and it is difficult to evacuate the flow of fossil CO2 140 generated by the calcination process toward the ends of the ceramic calcination tube 102 due to the poor permeability of the fine carbonate bed.

[0060] Discharge of the flow of fossil CO2 140 generated during the calcination process within the ceramic calcination tube 102 towards the cavity 1012 may conveniently occur from the slits 106 on the side surface of the ceramic calcination tube 102.

[0061] Thanks to the slits 106 arranged on its side surface, the ceramic calcination tube 102 can be completely filled by the flow of fine carbonate 110 and be able to evacuate the flow of fossil CO2 140 formed during the calcination process.

[0062] The flow of high-temperature exhaust gas 170 generated by the combustion of the flow of fuel gas 21 with the flow of oxygen 160 in the cavity 1012 used to provide at least part of the heat necessary to the apparatus for calcining fine quarry residues 100 is mainly formed by CO2, H2O, O2 and N2. The CO2 present in the flow of high-temperature exhaust gas 170 is produced by the combustion of CH4, CO and other hydrocarbons possibly present in the flow of fuel gas 21 and possibly by the flow of fossil CO2 140 generated by the calcination of the fine carbonate while the N2 derives from the amount of N2 possibly present in the flow of oxygen 160. The presence of O2 in the exhaust gas is due to the excess oxygen that is typically used in the complete combustion of fuels. The presence of water vapour in the exhaust gas is due to both the water vapour present in the flow of fuel gas 21, the combustion of H2, CH4 and other hydrocarbons possibly present in the flow of fuel gas 21 and to the flow of water vapour 161 possibly fed to the cavity 1012.

[0063] By feeding water vapour 161 to the cavity 1012, the partial pressure of the CO2 is lowered, favouring the escape of the flow of fossil CO2 140 from the slits 106 andlowering the temperature at which the calcination process of the flow of fine carbonate 110 takes place inside the ceramic calcination tube 102, benefiting the quality of the flow of oxide 630. In a manner known per se, by lowering the calcination temperature of the carbonate through a reduction in the partial pressure of CO2, the sintering problems of the same decrease, thus increasing the quality of the oxide produced, which is much more reactive than an oxide produced at higher temperatures and sintered.

[0064] The flow of high-temperature exhaust gas 170 released from the apparatus for calcining fine quarry residues 100 is a high enthalpy gas that can be conveniently used to improve the energy efficiency of the apparatus 100 according to the invention.

[0065] If contaminants such as sulphur, chlorine, ash or heavy metals were present in the flow of fuel gas 21 feeding the apparatus for calcining fine quarry residues 100 according to the invention, these would remain in the cavity 1012, without ever coming into contact with the fine carbonate inside the ceramic calcination tube 102, allowing one of the main problems of using the flow of fuel gas 21 from waste gasification to be overcome and offering a great cost reduction while maintaining a high quality of the produced flow of oxide 630.

[0066] Referring to figures 3-5, it is possible to see the shape of the ceramic material modules 105 that make up the ceramic calcination tube 102.

[0067] The ceramic material modules 105 preferably have a hollow rectangular shape with a wall thickness 506 < 50 mm and with the following dimensions:- length 501 less than 2000 mm;- width 503 less than 500 mm;- height 502 less than 1000 mm.

[0068] Calcium oxide CaO reacts at high temperature with nickel and chromium possibly present in the metal structures with which it comes into contact, so it is not possible to use metal calcination tubes, especially in the presence of oxidizing atmospheres.

[0069] In a manner known per se, at temperatures above 800 °C, the CaO reacts with Nickel (Ni) and with Chromium (Cr) forming respectively the compounds CaNiO2 and CaCr2O4 which adhere to the walls of the calciner tube preventing a free movement of the flow of fine carbonate 110 inside the ceramic calcination tube 102.

[0070] It is therefore convenient that the calcination tube 102 is not metallic but is made of ceramic material.

[0071] The ceramic material with which the ceramic material modules 105 are built is ideal for transmitting high temperature heat, withstanding thermal shocks and not reacting chemically with calcium oxide (CaO).

[0072] In particular, the use of silicon carbide (SiC) for the realization of the ceramic material modules 105 represents a possible and convenient technical solution.

[0073] Referring to the embodiment of figures 4, the ceramic calcination tube 102 is permeable to the escape of the flow of fossil CO2 140 generated in its inside by the calcination process towards the cavity 1012 where it mixes with the flue gases of the flow of fuel gas 21 and possibly to the flow of water vapour 161.

[0074] As described above, the ceramic calcination tube 102 is permeable to the flow of fossil CO2 140 due to the presence of the slits 106. In some embodiments, such as that of figures 3, the slits 106 are macroscopic openings, clearly visible in the overall view of the ceramic material module 105. In accordance with other embodiments, the slits 106 may have microscopic dimensions, i.e. markedly smaller and not visible in the overall view of the ceramic material module 105. Such microscopic slits 106 in fact make at least a part of the wall of the ceramic material module 105 porous.

[0075] The apparatus 100 according to the invention, being part of the category of fixed bed kilns, has much lower construction and operating costs and higher efficiencies than direct rotary kilns and fluidized bed kilns that can use fine quarry residues.

[0076] In accordance with a particular embodiment of the apparatus for calcining fine quarry residues 100 and always referring to figures 1 and 2, the supply of the flow of fuel gas 21 and of the flow of oxygen 160 are positioned so as to generate a combustion in the cavity 1012 existing between the adiabatic tube 101 and the ceramic calcination tube 102.

[0077] Combustion of the flow of fuel gas 21 with the flow of oxygen 160 generates at least part of the heat necessary for calcination of the fine carbonate particles 1101 and a flow of high-temperature exhaust gas 170 which is evacuated from the apparatus for calcining fine quarry residues 100.

[0078] The fine carbonate particles 1101 fed to the ceramic calcination tube 102 from the flow of fine carbonate 110, during their stay inside the ceramic calcination tube 102 receive the energy necessary for calcination (from the combustion of the flow of fuel gas 21 with the flow of oxygen 160 and from the electrical resistors 107), and are transformed into oxide particles 1301 by means of the known chemical reactionCaCOs CaO + CO2.

[0079] The oxide particles 1301 are then discharged from the ceramic calcination tube 102 by means of a system for the controlled discharge of the oxide (not shown in the figures) forming the flow of oxide 630.

[0080] The apparatus for calcining fine quarry residues 100 according to the invention overcomes the main limitations of the prior art by allowing the convenient use of fine carbonate and fuels of low economic value, potentially contaminated with sulphur, chlorine and toxic-harmful ash, while still allowing a high-quality flow of oxide 630 to be produced.

[0081] It is clear that the specific characteristics are described in relation to different embodiments of the apparatus and method with exemplary and non-limiting intent. Obviously, further modifications and variations may be made to the apparatus and the method according to the present invention by a person skilled in the art, in order to meet contingent and specific requirements, all of which are however within the scope of protection of the invention as defined by the following claims.

Claims

CLAIMS1. Apparatus for calcination of fine quarry residues (100), comprising an adiabatic tube (101) and a ceramic calcination tube (102), wherein:- the adiabatic tube (101 ) contains the ceramic calcination tube (102);- a cavity (1012) is defined between the adiabatic tube (101) and the ceramic calcination tube (102);- the adiabatic tube (101) comprises an inlet for the fuel gas (21), and an inlet for oxygen (160), and is configured to allow the combustion of a flow of fuel gas (21 ) with a flow of oxygen (160);- the ceramic calcination tube (102) is adapted to receive at its input a flow of fine carbonate (110), for the calcination reactions to take place inside itCaCO3— CaO + CO2and / orMgCO3- MgO + CO2and to release at its output a flow of oxide (630) and a flow of fossil CO2 (140); - the apparatus (100) comprises electrical resistors (107) positioned in the cavity (1012) and adapted to generate at least part of the heat necessary for the calcination reaction of the fine carbonate inside the ceramic calcination tube (102); wherein the ceramic calcination tube (102):- is made up of ceramic material modules (105);- comprises slits (106) for the escape of the flow of fossil CO2 (140) produced by the calcination;- allows the passage of the flow of fossil CO2 (140) generated by the calcination of the fine carbonate from the inside of the ceramic material modules (105) through the slits (106) towards the cavity (1012);- has a passage area between 0.01 m2and 1.00 m2;- has a length between 5 m and 100 m;wherein the adiabatic tube (101 ) is adapted to receive the flow of fossil CO2 (140) and to release at its output a single flow of high-temperature exhaust gas (170) comprising the fossil CO2 (140) and the gas produced by the combustion of the fuel gas (21) through the oxygen (160).

2. Apparatus for calcination of fine quarry residues (100) according to claim 1, wherein the ceramic material module (105) is a hollow profile and has one or more of thefollowing characteristics:- has a passage area between 0.01 m2and 1.00 m2;- has a height (502) less than 1 ,000 mm;- has a width (503) less than 500 mm;- has a length (501 ) less than 2,000 mm;- has a wall thickness (506) less than 50 mm;- is able to withstand temperatures above 1 ,000 °C;- has a heat transmission coefficient greater than 30 w / m / °C.

3. Apparatus for calcination offine quarry residues (100) according to claim 1 or 2, further comprising:- ceramic modules (105) forming slits (106) for the escape of the flow of fossil CO2 (140), produced by the calcination, when coupled with adjacent ceramic material modules (105).

4. Apparatus for calcination of fine quarry residues (100) according to one or more of the preceding claims, configured in such a way that the heat necessary for the calcination reaction of the fine carbonate inside the ceramic calcination tube (102) is provided in part by the electrical resistors (107) and in part by the combustion of the fuel gas (21 ).

5. Apparatus for calcination of fine quarry residues (100) according to one or more of the preceding claims, wherein the adiabatic tube (101 ) further comprises an inlet for a flow of water vapour (161 ) to lower the partial pressure of CO2 in the cavity (1012).

6. Apparatus for calcination of fine quarry residues (100) according to the preceding claim further comprising, downstream of the ceramic calcination tube (102), a hydrator (200) comprising:- an inlet for a flow of water (201 );- an inlet for at least a part of the flow of oxide (630) exiting the ceramic calcination tube (102).

7. Apparatus for calcination of fine quarry residues (100) according to the preceding claim, wherein the hydrator (200) is configured to react the water (201 ) with the oxide (630) according to at least one of the reactions:CaO + H2O Ca(OH)2MgO + H2O Mg(OH)2and to release a flow of hydroxide (230) and a flow of water vapour (161 ).Apparatus for calcination of fine quarry residues (100) according to the preceding claim, wherein the flow of water vapour (161) exiting the hydrator (200) is at least in part fed to the cavity (1012).

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