A fluid composition comprising carbon dioxide and process for the production thereof

Abstract

The present invention relates to a fluid composition comprising a CO2 content of least 20 mole percent on a dry basis, preferably at least 50 mole percent on a dry basis, in particular at least 80 mole percent on a dry basis wherein at least 0.6 10-12 parts of the CO2, preferably 0.8 10-12 parts of the CO2 are in the form 14CO2.

Description

A FLUID COMPOSITION COMPRISING CARBON DIOXIDE AND PROCESS FOR THE PRODUCTION THEREOFTechnical Field

[0001] The present invention relates to a fluid composition and a decarbonation process for producing said fluid composition.Background Art

[0002] The increasing concentration of carbon dioxide in the atmosphere is recognized as one of the causes of global warming, which is one of the greatest concerns of present days. This increase is largely owed to human actions and particularly to the combustion of carbon-containing fossil fuel, for instance for transportation, household heating, power generation, etc., and in energy-intensive industries such as steel, cement and lime manufacturing.

[0003] Within the lime-production process, natural limestone (mainly composed of calcium carbonate) is heated to a temperature above 900°C in order to cause its calcination into quicklime (calcium oxide) and carbon dioxide according to the following reversible reaction:CaCOs CaO + CO2 AH = 178 kJ / mol: Equation 1

[0004] Calcium oxide is considered as one of the most important raw materials and is used in a multitude of applications such as steel manufacturing, construction, agriculture, flue gas and water treatment as well as in glass, paper and food industry. The global annual production is estimated to be above 250 million tons.

[0005] As indicated in Equation 1 , CO2 is a co-product of the lime-production process meaning that approximately 760 to 790 kg of CO2 is unavoidably generated when producing 1 ton of lime. Moreover, the heat required for heating limestone and for conducting the reaction is usually provided by the combustion of a carbonaceous fuel, which results in additional production of CO2 (ranging between 200 and more than 700 kg per ton of lime depending on the nature of the fuel and efficiency of the kiln).

[0006] The use of vertical shaft kiln prevails in the lime industry as they are particularly suitable for the production of lumpy quicklime compared to other types of furnaces, such as rotary kiln, and because they have the advantage of lower specific energy input.

[0007] In a single-shaft vertical kiln, limestone or dolomitic limestone is fed through the top of the shaft and the produced lime is discharged at its bottom. In the pre-heating zone, the limestone is heated by hot gases flowing upward from the combustion zone. In the combustion zone, heat is produced through the direct firing of a fuel to reach a temperature above 900°C and consequently causing the decomposition of the limestone into quicklime and CO2. The lime then enters the cooling zone where it is cooled by air fed from the bottom of the shaft. The produced lime is finally discharged, ground and sieved into the desired particle size. Flue gas leaves the shaft at the top of the pre-heating zone and is fed to a filter system before it is vented to the atmosphere. Specific energy consumption for such single-shaft vertical kilns ranges between 4 and 5 GJ per ton of lime.

[0008] Parallel-flow regenerative kilns (PFRK) are a variant of vertical shafts that are considered as the best-available technology for lime production with design capacity up to 800 tons per day. They consist in vertical shafts (usually 2 or 3) connected by a crossover channel. Each shaft operates alternately according to a defined sequence. Initially, fuel is burnt in one of the shafts (“in combustion”) with combustion air flowing downwards (“parallel flow” with the limestone). Hot gases are then transferred to the other shafts (“in regeneration”) through the cross-over channel in order to pre-heat limestone in said other shafts. A reversal between combustion and regeneration shafts typically occurs every 15 minutes.

[0009] This operational mode enables optimal recovery of the heat contained in product and hot gases bringing the specific energy consumption down to around 3.6 GJ per ton of lime. The combustion of the fuels required to bring this heat results in the production of approximately 200 kg of CO2 per ton of lime when natural gas is used.

[0010] The lime industry is making efforts for reducing its CO2 emissions by improving energy efficiency (including investment in more efficient kilns), using lower-carbon energy sources (e.g., replacing coal by natural gas or biomass) or supplying lime plants with renewable electricity. The CO2 related to energy can thus be reduced to some extent. Nevertheless, none of these actions impacts the CO2 which is inherently produced during decarbonation of limestone.

[0011] A route for further reducing emission consists in capturing CO2 from the lime kiln flue gas for permanent sequestration (typically in underground geological formation) or recycling for further usage (e.g., for the production of synthetic fuels). Those processes are known under the generic term CCLIS (Carbon Capture, Utilization and Storage). To achieve carbon neutrality or even negative emissions in the near future, these measures are not sufficient, as long as CO2 from fossil origin is generated for instance in adecarbonation process or combustion, and the capacity of the CCLIS available cannot cover the overall CO2 emissions emitted by human activity.Aims of the Invention

[0012] The invention aims to provide a solution to overcome at least one drawback of the teachings provided by the prior art.

[0013] In particular, the present invention aims to ensure that the CO2 used for CCLIS is from non-fossil origin and optionally biomass origin, therefore warrantying that said CO2 used for CCLIS is atmospheric CO2. This could be obtained for example, via a Direct Air Capture or via the capture of CO2 generated by biomass combustion.

[0014] For the above purpose, the invention is directed to a fluid composition comprising a CO2 content of least 20 mole percent on a dry basis, preferably at least 50 mole percent on a dry basis, in particular at least 80 mole percent on a dry basis wherein at least 0.6 10'12parts of the CO2, preferably at least 0.8 10'12parts of the CO2 are in the form14CO2.

[0015] According to specific embodiments of the invention, the fluid composition comprises one or more of the following feature(s): the CO2 content is higher than 50 mole percent on a dry basis wherein less than 1 .5 10-12parts of the CO2 are in the form14CC>2; at least 0.7 10'12parts of the CO2, preferably at least 0.9 10'12parts of the CO2, more preferably at least 1.0 10'12parts of the CO2, in particular at least 1.1 10'12parts of the CO2 are in the form14CC>2; the fluid composition is a gas composition; the fluid composition is a liquid composition; the fluid composition is a supercritical fluid composition; solid particles fitting the formula : aCaCO3.bMgCO3.cCaMg(CO3)2.xCaO.yMgO.zCa(OH)2.tMg(OH)2.ul, wherein I are impurities; a, b, c, x, y, z, t and u each being mass fractions > 0 and < 100% based on the total weight of said particles, with a+b+c+x+y+z+t comprised between 50% and 100% based on the total weight of said particles, preferably between 80% and 100% based on the total weight of said particles; the solid particles have a diameter equal to or less than 10 micrometres (pm); less than 5 mole percent of O2 on a dry basis; less than 2 mole percent of NOX on a dry basis; a potassium content below 1000 ppm by weight, preferably below 500 ppm by weight, more preferably below 50 ppm by weight.

[0016] The invention is also directed to a decarbonation process for forming a or the fluid composition, comprising the following steps: supplying an alkaline earth carbonate composition, wherein the ratio of 14C / 12C in said alkaline earth carbonate composition is higher than 0.6 10-12, preferably higher than 0.8 10-12 and optionally less than 1.5 10-12; extracting a CO2 containing stream from the alkaline earth carbonate composition, preferably via calcination and / or electrolysis thereby forming a CO2 stream; optionally purifying the CO2 containing stream.

[0017] According to specific embodiments of the invention, the decarbonation process for forming a fluid composition comprises one or more of the following feature(s) / step(s): compressing the CO2 containing stream. the calcination is performed with electric energy and / or a combustion, wherein at least 50 wt. %, preferably at least 70 wt. % of the fuel used for the combustion is a biomass; the alkaline earth carbonate composition comprises an equivalent CO2 content of at least 18 wt. %, preferably at least 31 wt. %, more preferably at least 37 wt. %, in particular at least 41 wt. %; the biomass has an effective emission factor greater than 60000 kgCCh / TJ, preferably greater than 70000 kgCCh / TJ, more preferably greater than 80000 kgCCh / TJ, most preferably greater than 90000 kgCCh / TJ.

[0018] The features of the invention allow the production of CaO that is environmental friendly. They also provide a CO2 with (substantially) non-fossil origin and compatible for producing green products (such as e-fuels), thereby achieving carbon neutrality or carbon negative emissions when combined with a carbon capture and storage.Brief Description of Drawings

[0019] Aspects of the invention will now be described in more details with reference to the appended drawings, wherein same reference numerals illustrate same features.

[0020] Figure 1 shows a first embodiment according to the invention.

[0021] Figure 2 shows a specific embodiment of the first embodiment.

[0022] Figure 3 shows a second embodiment according to the invention.

[0023] Figure 4 shows a specific embodiment of the second embodiment.

[0024] Figure 5 shows a third embodiment according to the invention.Detailed description

[0025] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may however be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness.

[0026] On earth, there are three naturally occurring isotopes of carbon: carbon-12 (12C), which constitutes 99% of all carbon; carbon-13 (13C), accounting for 1.1 %; and carbon-14 (14C), which occurs in trace amounts, representing from 1 to 1 .5 atoms per 1012atoms of carbon in the atmosphere. The carbon isotope carbon-14 (14C) is a radioactive isotope of carbon characterized by an atomic nucleus containing 6 protons and 8 neutrons. While carbon-12 and carbon-13 are stable, carbon-14 is unstable with a halflife of 5700±30 years. The primary natural source of carbon-14 on Earth is cosmic ray action on nitrogen in the atmosphere.

[0027] The carbon-14 present in the atmosphere is primarily in the form of CO2. Since CO2 is one of the components of photosynthesis, plants maintain carbon-14 levels (ratio between carbon-14 to carbon-12) comparable to those in the atmosphere. Therefore, fuels derived from biomass have substantially the same levels of carbon-14 than those in the atmosphere.

[0028] Due to global warming, solutions to capture CO2 from the air have been developed, such as Direct Air Capture Processes (DAC) or Bionergy with carbon Capture and Storage (BECCS). The DAC process is a method used to remove carbon dioxide (CO2) directly from the atmosphere. Some DAC processes typically use sorbents to capture CO2 from the air. For example, sorbents are solid materials that adsorb CO2 molecules onto their surface. A sorbent can be made of alkaline earth oxide (e.g. CaO) and / or hydroxide composition (Ca(OH)2) that is exposed to ambient air or conditioned air, generating an alkaline earth carbonate composition (e.g. CaCCh). The alkaline earth carbonate composition is obtained by “pumping” CO2 directly from the atmosphere. Additionally, the resulting (alkaline earth) carbonate composition has a composition similar to limestone as it is rich in CaCCh.

[0029] Limestone, a sedimentary rock formed from the accumulation of organic material over millions of years, is typically derived from the skeletal remains of marine organisms such as coral and molluscs. Composed mainly of calcium carbonate (CaCCh), limestone can contain varying levels of carbon-14 depending on factors such as its age and the environment in which it formed. However, the carbon-14 levels in limestone sediment are significantly lower than those encountered in the atmosphere.

[0030] Although limestone composition is comparable to a carbonate composition obtained via a DAC process, as they are both rich in CaCCh, it is still technically possible to differentiate them by comparing their levels of carbon-14.

[0031] Figure 1 depicts a first embodiment of the invention, which enables the production of a CO2 fluid composition. A kiln is supplied with an alkaline earth carbonate composition obtained via at least one DAC process, and / or a synthetic CaCCh produced by capturing CO2 containing14CC>2 in flue gas with CaO and / or Ca(OH)2, such as a calcium looping applied to biomass power plant or to a e-fuels burning equipment. Under the heat generated by the combustion of the fuel, CO2 is released from the alkaline earth carbonate composition. The resulting fumes primarily consist of CO2 with a high level of carbon-14, comparable to that of the atmosphere. The CO2 fluid composition is valuable as it contains a high level of carbon-14, indicating that the CO2 is directly extracted from the atmosphere. Indeed, CO2 enriched in14C generated by a given process is a sign that this process is virtuous, enabling carbon-neutral emissions. If the CO2 is sequestered, negative emissions are expected. In contrast, CO2 lean in14C produced by another process would at best lead to carbon-neutral emissions, provided a CCUS system is in place. However, this cannot be guaranteed, especially in the short term. Furthermore, building CCUS capacity requires significant investment and energy usage, leading to further CO2 emissions that would only be compensated in the long run. Thanks to the measures of the invention, results in terms of CO2 emissions can already be achieved in the short term. Furthermore, quantifying the14C content in the CO2 fluid allows to monitor and trace the content of the fluid in atmospheric CO2 along the whole value chain.

[0032] Figure 2 illustrates a specific kiln, in particular a multi-shaft vertical kiln, that is suitable to generate the CO2 fluid composition according to the first embodiment. The multi-shaft vertical kiln MSVK in Figure 2 is based on a traditional parallel-flow regenerative kiln which is a specific case of multi-shaft vertical kiln. The multi-shaft vertical kiln, also designated kiln MSVK comprises a first 100 and a second 200 shaft with preheating zones 110, 210, heating zones 120, 220 and cooling zones 130, 230, as well as a cross-over channel 412 arranged between the first 100 and second 200 shafts. In use, the carbonated materials obtained through a DAC process 10 are introduced at an upper portion 111 , 211 of each shaft 100, 200. The carbonated materials 10 slowly move to the bottom. In the preheating zones 110, 210, the carbonated materials 10 are essentially preheated with the alternating regenerative exhaust gas 40. In the combustion zones 210, 220, the carbonated materials 10 are alternately heated by a combustion of fuel 20, from biomass origin, with at least one comburent 30, preferably depleted in nitrogen, in particular oxygen-enriched air or substantially pure oxygen, up to atemperature range in which carbon dioxide of the carbonated materials 10 is released. Both the combustion of the fuel 20 with the at least one comburent 30 and the decarbonation generate the exhaust gas 40. The exhaust gas recirculated 40 replaces the combustion air. In order to keep the same amount of oxygen supplied, an oxygen- enriched comburent can be used. The exhaust gas recirculation allows to generate high CO2 concentration in the exhaust gas 40 compatible with CO2 flue gas storage. Owing to these measures, the exhaust gas 40 exits the kiln MVSK with a high content of CO2 of at least 40 mole percent (dry volume), even 60 mole percent or more, wherein at least 0.6 10-12parts of the CO2, preferably 0.8 10'12parts of the CO2 are in the form14CO2 . Alternatively, a traditional parallel-flow regenerative kiln can be used when it is fed with a carbonate composition obtained via a DAC process. Compared to the kiln shown in Figure 2, a traditional parallel-flow regenerative kiln does not include the recycling of exhaust gas, nor does it require a supply of oxygen-enriched air or substantially pure oxygen. However, the resulting fumes require a CO2 concentration process to make them suitable for sequestration or use, which is not economically feasible with current technologies.

[0033] Measures to enhance the CO2 concentration exiting a kiln, while preventing or avoiding the mixing of CO2 and cooling air, are described in WO 2022 / 238384 A, WO 2022 / 238385 A, and WO 2022 / 238387 A. These measures can be applied to the kiln shown in Figure 2 or to a parallel-flow regenerative kiln to reduce the costs associated with post-CO2 concentration.

[0034] Likewise, a calciner as described in WO 2022 / 049137 or a mono shaft vertical kiln according to WO 12 / 072332 is also suitable when using alkaline earth carbonate materials, such as carbonate composition obtained via a DAC process, via capturing14CO2-containing CO2 in flue gas with CaO and / or Ca(OH)2.

[0035] The fumes exiting a kiln of the first embodiment can be concentrated in CO2 to reach a suitable level for sequestration or usage. The exhaust stream is then liquefied for sequestration or usage. Thanks to the measures of the invention, it can be guaranteed that the sequestered CO2 is sourced from the atmosphere, thereby improving its traceability. For instance, when the CO2 emitted by a lime kiln is generated using limestone from fossil origin, the CO2 sequestered is not as valuable as it is not directly taken from the atmosphere but instead from the ground, resulting in null net capture of CO2.

[0036] A second embodiment, illustrated in Figure 3, differs from the first embodiment in that the fuel is not from biomass origin but fossil origin. In this context, the CO2 produced will be less rich in 14C.

[0037] A third embodiment, illustrated in Figure 4, differs from the first or second embodiment in that electricity is used to heat the kiln. In this context, the CO2 produced is substantially as rich in 14C as that produced in the first embodiment, but more rich in 14C than that produced in the second embodiment.

[0038] Figure 5 illustrates a specific kiln as disclosed in WO 2022 / 049137, that is suitable to generate the CO2 fluid composition according to the third embodiment, where alkaline earth carbonated materials 10, such as carbonated composition obtained via a DAC process or14CaCO3 produced by capturing14CO2 with CaO or Ca(OH)2 in form of screened or ground particles, are fed into a first circuit 2, in which a first gas 4 circulates, said gas 4 being the exhaust gas of reactor 8. The particles of carbonated materials 10 are entrained / conveyed to the reactor 8 (in particular a flash calciner) where the decarbonation takes place under high temperatures. The heat source used in Figure 5 is an electric heating source. Alternatively, or in addition to an electric heating source, an combustion source (with combustion in-situ or indirect combustion via heat exchange) using at least one of biomass, fossil fuel, e-fuel, synthetic fuel, and / or H2 can be selected. The first gas 4 can be substantially free of nitrogen. For instance, the nitrogen represents less than 10% vol. in particular less than 5% vol. of the first gas composition. This facilitates the final purification of the exhaust gas 4 into a suitable purity for downstream CO2 use or sequestration. The first circuit 2 is therefore sealed from the ambient air. The first gas 4 is used to preheat the particles of carbonated materials 6. The first gas 4 mainly results from the CO2 being released during the decarbonation process in the reactor 8. It should be noted that the first gas 4 transports the particles of carbonated materials 6 away from the reactor 8, which is a gas source for the first gas 4 stream. In order to feed the reactor 8 with the particles of carbonated materials 10, a solid / gas separation, preferably an inertial separation is performed in separator 44 such as a cyclone. Separator 44 helps not only to separate the solid materials from the entraining gas, but also enhances heat exchanges. Indeed, the solid particles are efficiently heated by the entraining gas before being separated thanks to a proper distribution of the solid particles in the gas stream, a vast surface area of the solid gets in contact with the gas. Consequently, the solid and gas materials reach similar temperature in a very short time (typically a fraction of seconds). This type of heat exchanger is called solid-gas heat exchanger or suspension heat exchanger 44, and can typically contain several gas-solid separators to approach a counter current contact between the first gas 4 and the carbonated particles 10. Once the carbonated particles 10 are decarbonated in the reactor 8, the decarbonated particles 50 are transferred to a second circuit 12, preferably via a selective separation means 70 connecting the first and second circuits, 2 and 12. The selective separation means 70(sealing device) is arranged so as to allow the transfer of the particles of decarbonated materials 50 from the first circuit 2 to the second circuit 12 while substantially preventing the passage of gases 4 to circuit 12 and gases 14 to circuit 2. This selective separation means 70 can be selected from the group comprising a siphon element, a loop seal, single or multiple flaps, table feeder, cellular wheel sluice, fluid seal-pot, “Dollar” plate, or any of the following valves: rotary valves, cone valve, J valve, L valve, trickle valve and / or flapper valve. A second gas 14 substantially free of CO2 circulates in the second circuit 12, in order to avoid that the particles of decarbonated materials 50 react with the CO2 present in the first circuit 2. The CO2 in the second gas 14 preferably represents less than 5% vol.. The second gas 14 is not only used to transport the particles of decarbonated materials 50 but also to cool them in a dedicated solid-gas heat exchanger or suspension heat exchanger 24 containing gas-solid separators such as a cyclone or series of cyclones. Moreover, even if the quantity of CO2in the fumes from a lime / dolomite reactor is significant, the device of Figure 5 ensures that any gas mixture (second gas 14) used to cool quicklime / dolomitic quicklime through direct contact with the CaO / MgO is substantially free of CO2. This gas mixture (second gas 14) would therefore avoid any reconversion back to CaCO3 / MgCO3. Hence, the device of Figure 5 allows to bring the residual amount of carbonate in the limestone / dolomite to an acceptable level (e.g. less than 5% in weight).

[0039] The fumes (also known as exhaust gas or stream) generated in the previous embodiment comprise suspended particulates rich in calcium (Ca), magnesium (Mg), or both Ca and Mg. The presence of these particles (fitting the formula : aCaCO3.bMgCO3.cCaMg(CO3)2.xCaO.yMgO.zCa(OH)2.tMg(OH)2.ul, wherein I are impurities; a, b, c, x, y, z, t and u each being mass fractions > 0 and < 100% based on the total weight of said particles, with a+b+c+x+y+z+t comprised between 50% and 100% based on the total weight of said particles, preferably between 80% and 100% based on the total weight of said particles) is a signature that CO2 is produced from the calcination of an alkaline earth carbonate, particularly in a lime calciner.

[0040] By “biomass” is meant a fuel that at least 30%, preferably at least 50% in weight on dry basis is from animal and / or vegetal origin.

[0041] By an alkaline earth carbonate composition is meant a composition fitting the formula: aCaCO3.bMgCO3.cCaMg(CO3)2.xCaO.yMgO.zCa(OH)2.tMg(OH)2.ul, wherein I are impurities; x, y, z, t and u each being mass fractions > 0 and < 90%, a, b and c each being mass fractions > 0 and < 100%, with a + b + c > 10% by weight, based on the total weight of said carbonated materials, preferably x, y, z, t and u each being mass fractions> 0 and < 50%, a, b and c each being mass fractions > 0 and < 100%, with a + b + c > 50% by weight, based on the total weight of said carbonated materials.

[0042] An alkaline earth carbonate composition suitable for the invention typically comprises carbonated sorbent obtained via a DAC process and / or via a CO2 capture with a sorbent such as CaO and / or Ca(OH)2 from14C-containing flue gas. The carbonated sorbent is partially carbonated, with an equivalent CO2 content at least 18 wt. % (40.1 wt. % of CaCCh) preferably 31 wt. % (70 wt. % of CaCCh). Preferably, the alkaline earth carbonate composition suitable for the invention consists in carbonated sorbent. However, the alkaline earth carbonate composition suitable for the invention can be a mix of limestone and / or dolostone and carbonated sorbent. The level of carbon-14 in the claims defines both a minimum requirement in terms of carbonation level during the DAC process and the quantify of carbonated sorbent.

[0043] By “dry basis” is meant a fraction calculation excluding H2O such as water or steam.

[0044] By “CaCCh (enriched with Ca14CC>3)” is meant a calcium carbonate obtained by for example a direct air capture process or the capture of biogenic CO2 in a flue gas using a calcium based sorbent.

[0045] A calcium carbonate obtained by a direct air capture process contains CO2 from an atmospheric origin. Therefore, CO2 derived from the decarbonation of calcium carbonate, obtained by a direct air capture process, is designated as atmospheric CO2.

[0046] CO2 obtained from the combustion of biomass-based fuel is designated as biogenic CO2.

[0047] When calcium carbonate obtained with a direct air capture is calcined with a biomass-based fuel, the atmospheric CO2 resulting from the decarbonation and the biogenic CO2 resulting from the combustion of biomass-based fuel are generally mixed within the calciner, thereby forming a CO2 composition with both atmospheric and biogenic origins.

[0048] By CO2 effective emission factor is meant a CO2 default emission factor for stationary combustion in manufacturing industries and construction according to 2006 IPCC Guidelines for National Greenhouse Gas Inventories Volume 2 table 2.3: https: / / www.ipcc- nqqip.iqes.or.jp / public / 2006ql / pdf / 2 Volume2 / V2 2 Ch2 Stationary Combustion.pdf.

[0049] As used herein, the ratio of14C / 12C, as well as CO2 and14CO2 parts, have their ordinary technical meaning. So, the ratio of14C / 12C is preferably defined as a ratio of the number of14C atoms to the number of12C atoms. The parts of CO2 and14CO2 arepreferably used to determine the number of molecules of CO2 and14CC>2, which is equivalent to the number of atoms of C and14C.

[0050] Embodiments according to the invention are also defined by the following clauses:1. A fluid composition comprising a CO2 content of least 20 mole percent on a dry basis, preferably at least 50 mole percent on a dry basis, in particular at least 80 mole percent on a dry basis wherein at least 0.6 10'12parts of the CO2, preferably 0.8 10’12parts of the CO2 are in the form14CC>2.2. The fluid composition according to Clause 1 , wherein the CO2 content is higher than 50 mole percent on a dry basis wherein less than 1.5 10'12parts of the CO2 are in the form14CC>2.3. The fluid composition according to any of the preceding clauses, wherein the fluid composition is a gas composition.4. The fluid composition according to any of Clauses 1 to 2, wherein the fluid composition is a liquid composition.5. The fluid composition according to any of Clauses 1 to 2 wherein the fluid composition is a supercritical fluid composition.6. The fluid composition according to any of the preceding clauses, further comprising solid particles fitting the formula : aCaCO3.bMgCO3.cCaMg(CO3)2.xCaO.yMgO.zCa(OH)2.tMg(OH)2.ul, wherein I are impurities; a, b, c, x, y, z, t and u each being mass fractions > 0 and < 100% based on the total weight of said particles, with a+b+c+x+y+z+t comprised between 50% and 100% based on the total weight of said particles, preferably between 80% and 100% based on the total weight of said particles.7. The fluid composition according to the preceding clause, wherein the solid particles have a diameter equal to or less than 10 micrometres (pm).8. The fluid composition according to any of the preceding clauses, further comprising less than 5 mole percent of O2 on a dry basis.9. The fluid composition according to any of the preceding clauses, further comprising less than 2 mole percent of NOx on a dry basis.10. A decarbonation process for forming a fluid composition according to any of Clauses 1 to 9, comprising the following steps: supplying a alkaline earth carbonate composition, wherein the ratio of14C / 12C in said alkaline earth carbonate composition is higher than 0.6 10’12, preferably higher than 0.8 10-12and optionally less than 1 .5 10'12;extracting a CO2 containing stream from the alkaline earth carbonate composition, preferably via calcination and / or electrolysis thereby forming a CO2 stream; optionally purifying the CO2 containing stream.11. The process according to the preceding clause, further comprising compressing the CO2 containing stream.12. The process according to Clause 10 or 11 , wherein the calcination is performed with electric energy and / or a combustion, wherein at least 50 wt. %, 70 wt. % of the fuel used for the combustion is a biomass.

[0051] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

[0052] The foregoing description details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the invention may be practiced in many ways, and is therefore not limited to the embodiments disclosed. It should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to include any specific characteristics of the features or aspects of the invention with which that terminology is associated.

Claims

CLAIMS1. A fluid composition comprising a CO2 content of least 20 mole percent on a dry basis, preferably at least 50 mole percent on a dry basis, in particular at least 80 mole percent on a dry basis wherein at least 0.6 10'12parts of the CO2, preferably at least 0.8 10-12parts of the CO2 are in the form14CC>2.

2. The fluid composition according to Claim 1 , wherein the CO2 content is higher than 50 mole percent on a dry basis wherein less than 1.5 10'12parts of the CO2 are in the form14CC>2.

3. The fluid composition according to Claim 1 or 2, wherein at least0.7 10-12parts of the CO2, preferably at least 0.9 10'12parts of the CO2, more preferably at least 1.0 10'12parts of the CO2, in particular at least 1.1 10'12parts of the CO2 are in the form14CO2.

4. The fluid composition according to any of the preceding claims, wherein the fluid composition is a gas composition.

5. The fluid composition according to any of Claims 1 to 2, wherein the fluid composition is a liquid composition.

6. The fluid composition according to any of Claims 1 to 2 wherein the fluid composition is a supercritical fluid composition.

7. The fluid composition according to any of the preceding claims, further comprising solid particles fitting the formula : aCaCO3.bMgCO3.cCaMg(CO3)2.xCaO.yMgO.zCa(OH)2.tMg(OH)2.ul, wherein I are impurities; a, b, c, x, y, z, t and u each being mass fractions > 0 and < 100% based on the total weight of said particles, with a+b+c+x+y+z+t comprised between 50% and 100% based on the total weight of said particles, preferably between 80% and 100% based on the total weight of said particles.

8. The fluid composition according to the preceding claim, wherein the solid particles have a diameter equal to or less than 10 micrometres (pm).

9. The fluid composition according to any of the preceding claims, further comprising less than 5 mole percent of O2 on a dry basis.

10. The fluid composition according to any of the preceding claims, further comprising less than 2 mole percent of NOx on a dry basis.

11. The fluid composition according to any of the preceding claims, having a potassium content below 1000 ppm by weight, preferably below 500 ppm by weight, more preferably below 50 ppm by weight.

12. A decarbonation process for forming a fluid composition according to any of Claims 1 to 11 , comprising the following steps:supplying an alkaline earth carbonate composition, wherein the ratio of14C / 12C in said alkaline earth carbonate composition is higher than 0.6 10’12, preferably higher than 0.8 10-12and optionally less than 1.5 10'12; extracting a CO2 containing stream from the alkaline earth carbonate composition, preferably via calcination and / or electrolysis thereby forming a CO2 stream; optionally purifying the CO2 containing stream.

13. The process according to the preceding claim, further comprising compressing the CO2 containing stream.

14. The process according to Claim 12 or 13, wherein the calcination is performed with electric energy and / or a combustion, wherein at least 50 wt. %, preferably at least 70 wt. % of the fuel used for the combustion is a biomass.

15. The process according to any of Claims 12 to 14, wherein the alkaline earth carbonate composition comprises an equivalent CO2 content of at least 18 wt. %, preferably at least 31 wt. %, more preferably at least 37 wt. %, in particular at least 41 wt. %.

16. The process according to any of Claims 12 to 15, wherein the biomass has an effective emission factor greater than 60000 kgCCh / TJ, preferably greater than 70000 kgCCh / TJ, more preferably greater than 80000 kgCCh / TJ, most preferably greater than 90000 kgCCh / TJ.

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