Method for quantifying a fraction of carbon dioxide from a single-phase liquid mixture

Abstract

The invention relates to a method (1000) for quantifying a fraction of carbon dioxide from a mixture injected into an aquifer reservoir, comprising: - a step (140) of loading parameters comprising: · a concentration of carbon dioxide, · an isotopic signature of the carbon, · an isotopic and elemental composition of noble gases comprising at least xenon, argon and helium, - a step (160) of comparing with injection parameters comprising: · an initial concentration of carbon dioxide, · an initial isotopic signature of the carbon, · an initial isotopic and elemental composition of noble gases, comprising at least xenon, argon and helium, the comparison step comprising a calculation of the elemental ratios of helium, xenon and argon, - a step (170) of determining an amount of carbon dioxide lost, - a step (200) of calculating an amount of carbon dioxide mineralized.

Description

METHOD FOR QUANTIFYING A FRACTION OF CARBON DIOXIDE FROM A MONOPHASIC LIQUID MIXTURE

[0001] The invention relates to the field of sequestration of anthropogenic carbon dioxide emissions, and more particularly to the geochemical tracing of carbon dioxide stored underground. The invention proposes a new method that allows, on the one hand, the tracing of carbon dioxide injected in dissolved form into an aquifer reservoir mainly composed of igneous rocks, and on the other hand, the quantification of the injected fraction of carbon dioxide that has been carbonated.

[0002] Below, we describe the known prior art from which the invention was developed.

[0003] Carbon capture and geological storage (CCGS) is one solution that allows for the reduction of emissions from large industrial sites without changing production methods. It works by capturing CO2 from flue gases and then transporting it for long-term storage in subsurface geological formations. Subsurface CO2 storage is achieved through various physical and chemical trapping mechanisms. Only certain geological environments are suitable, as the necessary conditions are specific.

[0004] Certain geological environments can be used for storing CO2 in its gaseous state, such as depleted oil and gas reservoirs, as well as deep saline aquifers found in sedimentary basins. Other geological environments are preferred for storing CO2 in its solid, or carbonate, form, particularly in aquifers composed of igneous rocks. Injecting dissolved CO2 triggers dissolution reactions of the silicates that make up these rocks, followed by the precipitation of CO2 as carbonates. However, no robust method has yet been established to accurately quantify the proportion of carbonated CO2 relative to the total amount of CO2 injected. Indeed, the specific risks associated with CO2 storage concern both the operational phase (injection) and the post-operational phase.The most worrying are those related to the possibility of short- or long-term CO2 leaks for the non-carbonate fraction of CO2.

[0005] An approach has been proposed to quantify carbonation by injecting an artificial tracer (SF6 and / or SF5CF3) by Juerg M, Matter et al., "Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions," Science, June 2016. However, the use of this method remains limited and only allows for maximum quantification of carbonation. Indeed, the loss of CO2 relative to SF6 induces a decrease in the CO2 / SF6 ratio, and the quantification of the percentage of CO2 loss by carbonation is based on the difference between the measured CO2 / SF6 ratio and the initial CO2 / SF6 ratio (at the time of injection). Furthermore, this method does not take into account SF6 losses that could occur depending on the rock composition of the aquifer. In particular, SF6 exhibits strong reactivity with lithium, which can pose a problem in tracing basaltic minerals.The differing solubility properties of CO2 and SF6 in aqueous phases also have a significant impact, as does potential differential adsorption depending on the system. Therefore, the direct relationship between the decrease in CO2 characterizing an equivalent carbonate volume cannot be accurately estimated without considering other losses that may occur and that directly affect the quantification of carbonation.

[0006] There is therefore a need for a new solution which makes it possible to determine, more precisely, compared to the approach based solely on tracers of type SF6 or SF5CF3, the proportion of carbonated CO2 relative to a quantity of CO2 injected into an aquifer reservoir mainly composed of igneous rocks.

[0007] The invention aims to overcome these drawbacks. The following presents a simplified summary of selected aspects, embodiments, and examples of the present invention in order to provide a basic understanding of the invention. However, this summary does not constitute an exhaustive overview of all aspects, embodiments, and examples of the invention. Its sole purpose is to present selected aspects, embodiments, and examples of the invention in a concise form as an introduction to the more detailed description of the aspects, embodiments, and examples of the invention that follows the summary.

[0008] According to a first aspect, the invention relates to a method for quantifying a fraction of carbon dioxide from a liquid monophasic mixture, composed of at least water and carbon dioxide, injected into an aquifer reservoir, said method being implemented by a computer device and comprising: a step of loading, from a data memory, tracing parameters of a sample of the liquid monophasic mixture injected into the aquifer reservoir, taken at a second time point, said sample comprising water from the aquifer and a quantity of the liquid monophasic mixture injected at a first time point, said tracing parameters comprising: a carbon dioxide concentration, a carbon isotopic signature, an isotopic and elemental composition in rare gases comprising at least Xenon, Argon and Helium, a comparison step, by a processor of said computer device,tracing parameters to reference injection parameters determined in the mixture composed of water and a quantity of carbon dioxide injected at the first instant, said reference injection parameters comprising: an initial carbon dioxide concentration, an initial carbon isotopic signature, an initial isotopic and elemental composition in noble gases, comprising at least Xenon, Argon and Helium, the comparison step further comprising a calculation of the elemental ratios of Helium, Xenon and Argon, and where the comparison step indicates a variation in the elemental ratios of noble gases between the tracing parameters and the reference injection parameters, the process comprises: a step of determination, by the processor, of a quantity of carbon dioxide lost including: a calculation of the isotopic ratios of Helium, Xenon and Argon of the tracing parameters and the reference injection parameters,a calculation of the variation in the carbon isotopic signature of the tracing parameters relative to the reference injection parameters, an estimation of the amount of carbon dioxide lost based on a mathematical law that links said amount to the variation of at least one elemental ratio of Helium, Argon and / or Xenon as a function of the calculated isotopic and elemental ratios, and the variation in the carbon isotopic signature, a calculation step, by the processor, of the amount of carbon dioxide mineralized based on a mathematical law that links the estimate of the carbon dioxide lost and the amount of carbon dioxide injected at the first instant.

[0009] According to other optional features of the process, the latter may optionally include one or more of the following features, alone or in combination: The comparison step further includes a calculation of the carbon dioxide to helium ratio of the reference tracing and injection parameters, and in which, when the comparison step indicates: a preferential decrease in Xenon, a decrease in the carbon dioxide to helium ratio, that the isotopic ratios of Argon and Helium of the calculated reference tracing and injection parameters are unchanged, the variation in the elemental ratio taken into account in the estimation of a quantity of carbon dioxide lost corresponds to the Xenon to Helium ratio.The comparison step further includes a calculation of the carbon dioxide to helium ratio of the tracer parameters and the reference injection parameters, and in which, when the comparison step indicates: a preferential decrease in helium, that the isotopic ratios of argon and xenon of the calculated tracer parameters and reference injection parameters are unchanged, said process includes a step of adjusting the elemental composition of helium of the tracer parameters. The estimate of the quantity of carbon dioxide lost, noted. ,is calculated according to the following mathematical law: , Or is the ratio between a mass of active rock in the reservoir and a given volume of water, said ratio being preferably calculated according to the following equation: , with The comparison step further includes a calculation of the carbon dioxide to helium ratio of the tracing parameters and the reference injection parameters, and in which, when the comparison step indicates: a preferential decrease in helium, an increase in the carbon dioxide to helium ratio, a decrease in the argon and xenon isotopic ratios of the tracing parameters with respect to the corresponding ratios of the reference injection parameters, the determination step includes an estimation of a second quantity of carbon dioxide lost from a second mathematical law that relates said quantity to the elemental ratio of xenon to helium. The estimation of the second quantity of carbon dioxide lost, denoted is calculated according to the following second mathematical law: , Or , with ; the concentrations of Xenon and Helium measured at the first instant in the injected mixture, and ; the concentration of this same species measured at the second time step in a sample taken from the aquifer reservoir and the Fick diffusion coefficients of the corresponding species. The reference tracing parameters and injection parameters include respectively a divalent cation concentration containing at least Mg 2+ Fe 2+ and / or That 2+ and an initial concentration of divalent cations containing at least Mg 2+ Fe 2+ and / or That 2+The process includes a step of verifying a dissolution in which the divalent cation ratios are calculated, and when at least one divalent cation ratio indicates an increase in the concentration of said cation in the tracing parameters, the comparison step is implemented. It includes a step of determining, at first instant, a carbon dioxide concentration, a carbon isotopic signature, and an isotopic and elemental composition of rare gases comprising at least Xenon, Argon, and Helium of a single-phase liquid mixture composed of at least water and a quantity of carbon dioxide to be injected. It includes a step of determining a carbon dioxide concentration, a carbon isotopic signature, and an isotopic and elemental composition of rare gases comprising at least Xenon, Argon, and Helium of an aquifer reservoir.It includes a step of injecting, at a first instant, into the aquifer reservoir a single-phase liquid mixture composed at least of water and carbon dioxide. It includes a step of taking, at a second instant, a fraction of carbon dioxide from the single-phase liquid mixture.

[0010] According to a second aspect, the invention relates to a non-transient computer-readable medium storing executable instructions which, when executed by a processor of a computer device, implement a process according to the invention.

[0011] According to a third aspect, the invention relates to a computer device for the quantification of a fraction of carbon dioxide from a single-phase liquid mixture, said computer device comprising a processor configured to implement a process according to the invention.

[0012] Other features and advantages of the invention will be better understood from the following description and with reference to the attached drawings, given for illustrative purposes only and not for limitation.

[0013] Figure 1 represents a flowchart illustrating the different steps of a process for quantifying a fraction of carbon dioxide from a single-phase liquid mixture according to the invention. The steps shown in dotted lines are optional.

[0014] Several aspects of the present invention are described with reference to flow diagrams and / or process block diagrams according to embodiments of the invention.

[0015] In the figure, the flow diagrams and / or block diagrams show the architecture, functionality and possible implementation of devices or systems or processes and computer program products, according to several embodiments of the invention.

[0016] To this end, each box in flowcharts or block diagrams can represent a system, device, module, or code that includes several executable instructions to implement the specified logical function(s). In some implementations, the functions associated with the box may appear in a different order than shown in the figures. For example, two boxes shown successively may be executed almost simultaneously, or boxes may sometimes be executed in reverse order, depending on the functionality involved.

[0017] Each box in flowcharts or block diagrams and combinations of boxes in flowcharts or block diagrams can be implemented by special systems that perform the specified functions or actions or execute combinations of special equipment and computer instructions.

[0018] Thus, as specialists in the field will appreciate, aspects of the present invention can be implemented in the form of a device, system, method, or computer program product. Accordingly, aspects of the present invention can take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, microcode, etc.), or a particular implementation such as a "circuit," "module," or "system." Furthermore, aspects of the present invention can take the form of a computer program product embedded in one or more computer-readable media, including computer-readable program code embedded therein.

[0019] Any combination of one or more computer-readable media may be used. For the purposes of this document, computer-readable media can be any tangible medium that can contain or store a program for use by or in connection with an instruction-executing system, device, or apparatus. Computer-readable media may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or apparatus, or any appropriate combination thereof. More specific examples (this list is not exhaustive) of computer-readable storage media would include: a hard drive, random access memory (RAM).

[0020] The computer program code for performing operations related to aspects of the present invention may be written in any combination of one or more programming languages, including an object-oriented programming language such as Java, C++, or similar; the C programming language or similar programming languages; a scripting language such as Perl or similar languages; and / or functional languages ​​such as Meta Language. The program code may run entirely on a user's computer, partially on a user's computer and partially on a remote computer, or entirely on the remote computer or server. In this last scenario, the remote computer may be connected to the user's computer over any type of network, including a local area network (LAN) or a wide area network (WAN).

[0021] These computer program instructions can be stored on a computer-readable medium capable of directing a computing device (e.g., a computer, a server, etc.), so that the instructions stored in the computer-readable medium enable a configured computing device to implement the invention.

[0022] Below, we describe a summary of the invention and the associated vocabulary, before presenting the disadvantages of the prior art, and finally showing in more detail how the invention remedies them.

[0023] In the following description, the term "noble gases" refers to a series of chemically inert elements that have similar properties and are naturally scarce. They are designated in group "18" (formerly VIIIA), or even group "0" of the periodic table, which includes helium, neon, argon, krypton, xenon, and radon.

[0024] In this document, the term "isotope" refers to two nuclides of the same chemical element that share the same number of protons but have different numbers of neutrons. For example, argon can exist as one of the following three stable isotopes: 40 Ar, which has 18 protons and 22 neutrons, 38 Ar, which has 18 protons and 20 neutrons, and 36 Ar, which has 18 protons and 18 neutrons.

[0025] In this document, the term "aquifer" refers to an area where water is found in a porous rock medium. This water present in the porous medium may originate from the recharge of surface waters such as rainwater or seawater which then migrates through the permeable rock into the subsoil, and / or from water trapped in sediments during burial and which remains in place.

[0026] As used here, the term "reservoir" can refer to an underground group of predominantly igneous, partially porous rocks capable of storing an accumulation of fluids. These are generally granite or basalt, but not exclusively, and whose sealing mechanism has allowed the formation of a reserve or accumulation. In the context of the invention, the aquifer reservoirs of interest are primarily composed of igneous rocks, unlike conventional reservoir rocks (which contain hydrocarbons) that are largely composed of sedimentary rocks, particularly sandstone or limestone, and which are not suitable for the short-term storage of CO2 in carbonate form, i.e., directly observable less than one year after CO2 injection.

[0027] The terms "process," "calculate," "determine," "display," "extract," "compare," or more broadly, "executable operation," are used in the context of this invention to refer to any action performed by a computer device or processor, unless the context indicates otherwise. In this regard, operations relate to actions and / or processes of a data processing system, such as a computer system or electronic computing device, which manipulates and transforms data represented as physical (electronic) quantities in the computer system's memory or other information storage, transmission, or display devices.Specifically, computational operations are performed by the computer's processor, the resulting data is entered into a corresponding field in a data memory, and this or these fields can then be presented to a user, for example, via a Human-Machine Interface that formats such data. These operations can be based on applications or software.

[0028] The terms or expressions "application," "software," "program code," and "executable code" refer to any expression, code, or notation representing a set of instructions intended to cause a data processor to perform a particular function, either directly or indirectly (for example, after conversion to another code). Examples of program code may include, but are not limited to, a subroutine, a function, an executable application, source code, object code, a library, and / or any other sequence of instructions designed to be executed on a computer system.

[0029] For the purposes of this invention, "processor" means at least one hardware circuit configured to perform operations according to instructions contained in code. The hardware circuit may be an integrated circuit. Examples of processors include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), and a programmable logic device (PLC). A single processor or several other units may be used to implement the invention.

[0030] The term "computer system" refers to any device comprising a processing unit or processor, for example in the form of a microcontroller, cooperating with a data memory, possibly a program memory, these memories being potentially separate. The processing unit cooperates with these memories by means of internal communication buses.

[0031] When introducing elements of various embodiments of the present invention, the articles "a," "an," and "the" are intended to signify that there is one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than those listed.

[0032] As already mentioned, implementing a robust tracing method to monitor the actual volume of carbonated CO2 is a major challenge for deploying geological CO2 capture and storage. To address this issue, the inventors have developed a solution that tracks the evolution of the isotopic and elemental composition of a combination of rare gases, from which a relative loss due to physical phenomena that can occur during storage—namely diffusion, adsorption, and / or confinement—is determined.

[0033] Thus, according to a first aspect, the invention, described in connection with the, relates to a method of quantifying 1000 a fraction of carbon dioxide from a single-phase liquid mixture, the method of quantifying 1000 includes a step of loading 140 of tracing parameters, a step of comparing 160 the tracing parameters to determined reference injection parameters, a step of determining 170 a quantity of carbon dioxide lost and a step of calculating 200 a quantity of mineralized carbon dioxide.As will be detailed later, the reference tracing parameters and injection parameters correspond to numerical values ​​determined from samples of a real aquifer reservoir existing in the physical world, while the quantities of carbon dioxide lost and mineralized correspond respectively to the quantity of carbon dioxide that has leaked, i.e. physically removed from the aqueous phase of the single-phase liquid mixture, for example by a phenomenon of diffusion, adsorption and / or confinement, and to that which has transformed into a solid mineral relative to the quantity of carbon dioxide originally injected into said real aquifer reservoir.

[0034] In the context of the invention, the liquid monophasic mixture is composed at least of water, and may also be composed of fresh water, seawater, or brine such as a sodium chloride solution in water, and carbon dioxide. The fraction of carbon dioxide that is the subject of quantification originates from the liquid monophasic mixture previously injected into an aquifer reservoir.

[0035] In this respect, a quantification method 1000 according to the invention may include an optional first determination step 110-1, at a first instant which may correspond to a pre-injection instant, d’une concentration en dioxyde de carbone, d’une signature isotopique du carbone, d’une composition isotopique et élémentaire en gaz rares comportant au moins le Xénon, l’Argon et l’Hélium du mélange monophasique liquide composé au moins d’eau et d’une quantité de dioxyde de carbone à injecter. Cette étape peut par exemple permettre de générer des paramètres d’injection de référence.

[0036] More specifically, the single-phase liquid mixture may comprise water, preferably brine, from the aquifer into which the mixture is intended to be injected, combined with a quantity of carbon dioxide to be injected for storage in the aquifer. The quantity of carbon dioxide to be injected is preferably dissolved in water, and even more preferably in brine.

[0037] Furthermore, a quantification method 1000 according to the invention may include an optional second step 110-2 for determining the carbon dioxide concentration, the carbon isotopic signature, and the isotopic and elemental composition of noble gases comprising at least Xenon, Argon, and Helium in the aquifer reservoir. The first and second determination steps 110-1 and 110-2 may be carried out concurrently.

[0038] It is intended that the quantification process 1000 can be implemented directly on site; therefore, it may include an initial injection step 120 of a single-phase liquid mixture composed of at least water and carbon dioxide into the aquifer. The quantification process 1000 may further be followed by a subsequent sampling step 130 of a fraction of carbon dioxide from the single-phase liquid mixture.

[0039] As illustrative examples, the injection step 120 can be carried out using a water injection system commonly employed in enhanced oil recovery in conjunction with an injection well. Furthermore, the sampling step 130 can be performed via the injection well or via a separate sampling well. Specifically, sampling step 130 can be performed using a tapping system connected to the sampling well or the injection well and configured to continuously collect a fraction of the liquid monophasic mixture, i.e., a sample composed of a mixture of aquifer water and a quantity of the injected liquid monophasic mixture. Each fraction of the liquid monophasic mixture can then be analyzed by mass spectrometry.

[0040] The composition of the single-phase liquid to be injected, the carbon dioxide fraction of the single-phase liquid mixture, or even the aquifer reservoir, before and after injection, can thus be analyzed.

[0041] Thus, as already mentioned, a quantification method 1000 according to the invention comprises a step 140 of loading, from a data memory, tracing parameters of a sample of the single-phase liquid mixture injected into the aquifer reservoir, taken at a second time point. The quantification method 1000 according to the invention is implemented by a computer device. By way of illustration, the computer device can be configured to load the tracing parameters from a remote server on which they are stored or directly from an internal data memory.

[0042] Advantageously, the loading step 140, as well as the subsequent steps described later, can be implemented at predetermined time intervals to monitor the evolution of the amount of carbon dioxide present in the aquifer. Thus, the second time point can correspond to a sample taken at a given time interval post-injection.

[0043] The tracer parameters thus obtained are derived from a sample taken at the second time step from a mixture composed of aquifer water and a quantity of the single-phase liquid mixture injected at the first time step. The tracer parameters include: a carbon dioxide concentration, a carbon isotope signature, and an isotopic and elemental composition of noble gases containing at least Xenon, Argon, and Helium.

[0044] The quantification method 1000 according to the invention then comprises a comparison step 160, by a processor of said computer device, of the tracing parameters to reference injection parameters determined in the mixture composed of water and a quantity of carbon dioxide injected at the first instant. The reference injection parameters include: an initial carbon dioxide concentration, an initial carbon isotopic signature, and an initial isotopic and elemental composition of noble gases, comprising at least Xenon, Argon, and Helium.

[0045] Furthermore, comparison step 160 includes a calculation of the elemental ratios of Helium, Xenon, and Argon, notably from the elemental compositions of the tracer parameters and the reference injection parameters. From these ratios, comparison step 160 is configured to indicate a variation 160-Y in the elemental ratios of noble gases. When no variation in the elemental composition of noble gases is detected 160-N by comparison 160 of the elemental ratios of Helium, Xenon, and Argon, the quantification process 1000 proceeds directly to the calculation step 200 of a quantity of mineralized carbon dioxide, which will be detailed later in the description.Indeed, this may indicate that the estimate of a quantity of carbon dioxide lost, that is to say physically subtracted from the aqueous phase of the single-phase liquid mixture, is zero and therefore that the quantity of mineralized carbon dioxide is directly proportional to the carbon dioxide concentration of the tracing parameters.

[0046] In the rest of the description, we note the concentration of the measured species at the first instant in the injected mixture, and the concentration of this same species measured at the second time step in a sample taken from the aquifer reservoir, which includes the previously injected liquid monophasic mixture belonging to the {CO2, He, Ar, Xe} complex. Furthermore, it is noted And the elementary ratios of species i to species j respectively at the first instant and at the second instant, j belonging to the set {CO2, He, Ar, Xe}.

[0047] Thus, when the comparison step 160 indicates a variation 160-Y of the elemental ratios in rare gases between the tracing parameters and the reference injection parameters, the quantification process 1000 according to the invention is configured to implement a determination step 170, by the processor, of a quantity of carbon dioxide lost.The determination step 170 includes: a calculation of the isotopic ratios of Helium, Xenon and Argon of the tracing parameters and the reference injection parameters, a calculation of a variation of the isotopic signature of carbon of the tracing parameters with respect to the reference injection parameters, an estimation of a quantity of carbon dioxide lost from a mathematical law which relates said quantity to the variation of at least one elemental ratio of Helium, Argon and / or Xenon as a function of the calculated isotopic and elemental ratios, and the variation of the isotopic signature of carbon.

[0048] Taking into account the evolution of the isotopic and elemental ratios of Helium, Xenon and Argon in combination with the variation of the isotopic signature of carbon makes it possible to estimate the proportion of carbon dioxide lost via physical phenomena by diffusion or adsorption and which could be falsely associated with the phenomenon of carbonation thus leading to an incorrect estimate of the amount of carbon dioxide stored.

[0049] Preferably, the isotopic ratios of the calculated tracing parameters and reference injection parameters may include: 3 Hey, 4 Hey, 40 Ar, 36 Ar, 129 Xe, 130 Xe, 132 Xe, 136 Xe.

[0050] Based on the estimate of the amount of carbon dioxide lost determined in step 170, a quantification process 1000 according to the invention includes a calculation step 200, by the processor, of a quantity of mineralized carbon dioxide based on a mathematical law that links the estimate of the amount of carbon dioxide lost and the amount of carbon dioxide injected at the first instant

[0051] The physical loss of carbon dioxide in the single-phase liquid mixture injected into the aquifer can, for example, be attributed to an adsorption phenomenon and is described by well-known mathematical laws such as Henry's law, which describes the adsorption of a dissolved gas onto a solid surface, or Langmuir's law, which describes adsorption onto a solid surface when the surface overlap is not negligible. As illustrative examples, Henry's law for a species is given by:

[0052] , Or is the amount of species adsorbed per unit solid mass and the adsorption coefficient of said species under the reservoir conditions.

[0053] The fraction of CO2 lost by adsorption is then given by:

[0054] , Or is the ratio between the mass of active rock and the volume of water considered, which can be obtained by:

[0055] , with

[0056] The estimation of the amount of carbon dioxide lost via adsorption or diffusion phenomena is thus taken into consideration in the overall balance of the carbon dioxide actually carbonated, which allows for a precise estimation of the amount of carbon dioxide that has leaked, i.e. physically removed from the aqueous phase of the single-phase liquid mixture, from the aquifer reservoir over the determined period and of the amount of carbon dioxide stored by carbonation.

[0057] According to one embodiment of a quantification process 1000 according to the invention, the comparison step 160 may further include a calculation of the carbon dioxide to helium ratio of the tracing parameters and the reference injection parameters and when the comparison step 160 indicates: a preferential decrease of Xenon, a decrease in the carbon dioxide to helium ratio, that the isotopic ratios of Argon and Helium of the calculated tracing parameters and the reference injection parameters are unchanged, the variation of the elemental ratio taken into account in the estimation of a quantity of carbon dioxide lost 170-1 may correspond to the Xenon to Helium ratio.

[0058] One of the objectives of the invention is to enable the identification and quantification of the carbon dioxide actually stored in the aquifer. However, a significant proportion of carbon dioxide can undergo adsorption, to a greater or lesser extent depending on the rock composition of the aquifer and its evolution over time. A decrease in the carbon dioxide-to-helium ratio is an initial indicator that adsorption has occurred, as carbon dioxide has a greater adsorption capacity than helium, and, a priori, greater than all noble gases. Regarding relative adsorption effects, noble gases cover a very wide range of adsorption capacities.The observation of a preferential decrease in Xenon based on the calculated elemental ratios, and more specifically the ratio of Xenon (which has the highest adsorption capacity of the noble gases considered) to Helium (which is not adsorbed or is only minimally adsorbed onto surfaces), combined with an unchanged isotopic distribution, can characterize such an adsorption phenomenon. The variation in the Xenon-to-Helium ratio compared to the initial ratio can indirectly quantify the fraction of CO2 adsorbed.

[0059] Alternatively or in addition, the comparison step 160 may further include a calculation of the carbon dioxide to helium ratio of the tracing parameters and the reference injection parameters, and when the comparison step 160 indicates: a preferential decrease of helium, that the isotopic ratios of argon and xenon of the calculated tracing parameters and the reference injection parameters are unchanged, the quantification process 1000 according to the invention may include an adjustment step 180 of the elemental composition of helium of the tracing parameters.

[0060] Indeed, as previously discussed, the use of elemental and isotopic ratios, and more specifically that of helium, to describe the behavior of carbon dioxide in the aquifer is of considerable importance. Helium can undergo a storage effect in highly confined environments; that is, it can preferentially migrate into a portion of igneous rock with low permeability to the single-phase liquid mixture, thus inducing a decrease in the proportion of helium present in the aquifer. This can introduce bias in the determination of the amount of carbon dioxide lost, since the amount of helium lost through confinement should not be correlated with a loss of carbon dioxide, particularly through diffusion. Therefore, an indication of a decrease in helium, characterized by an increase in the carbon dioxide-to-helium ratio, may indicate the presence of such a phenomenon.The adjustment step 180 can thus be implemented before the determination step 170 and can consist of modifying the value of the helium elemental composition of the tracing parameters. The comparison step 160 is then implemented again with the corrected helium elemental composition of the tracing parameters.

[0061] In one embodiment of the quantification process 1000 according to the invention, the comparison step 160 may further include a calculation of the carbon dioxide to helium ratio of the tracing parameters and the reference injection parameters, and when the comparison step 160 indicates: a preferential decrease of helium, an increase in the carbon dioxide to helium ratio, a decrease in the isotopic ratios of argon and xenon of the tracing parameters with regard to the corresponding ratios of the reference injection parameters, the determination step 170 may include an estimation of a second quantity of carbon dioxide lost 170-2 from a second mathematical law which relates the quantity to the elemental ratio of xenon to helium.

[0062] This allows for the identification and quantification of the carbon dioxide actually stored in the aquifer, while taking into account the proportion of carbon dioxide lost through diffusion. An increase in the carbon dioxide-to-helium ratio is an initial indicator that diffusion has occurred. Indeed, diffusion takes place outside of thermodynamic equilibrium, and elemental and isotopic fractionation will thus generate variations between the different quantifiable elements and isotopes. In particular, helium, due to its lower neutron content, will tend to diffuse more rapidly than other elements. The observation of a preferential decrease in helium, based on calculated elemental ratios and especially the xenon-to-helium ratio combined with a co-evolving isotopic distribution, can characterize such a diffusion phenomenon.The variation in the Xenon to Helium ratio compared to the initial ratio can indirectly quantify the fraction of CO2 diffused.

[0063] As an illustrative example, the physical loss of carbon dioxide in the single-phase liquid mixture injected into the aquifer reservoir can be attributed to a diffusion phenomenon and is described by a well-known mathematical law such as the Rayleigh-type fractionation law based on the diffusion coefficients D i Fick's law of the species considered in a given aquifer. The Rayleigh-type fractionation law for a species i, taking Helium as the reference, is given by:

[0064]

[0065] The fraction of CO2 lost by diffusion is then given by:

[0066]

[0067] Alternatively or in addition, the tracing parameters and reference injection parameters of a quantification method 1000 according to the invention may respectively include a divalent cation concentration comprising at least Mg 2+ Fe 2+ and / or That 2+ and an initial concentration of divalent cations containing at least Mg 2+ Fe 2+ and / or That 2+ The quantification process 1000 can thus include a verification step 150 of a dissolution in which the said divalent cation ratios are calculated, and when at least one divalent cation ratio indicates an increase in the concentration of said cation in the tracing parameters, the comparison step 160 is implemented. This makes it possible to highlight the initiation of a mineral dissolution that precedes the start of carbon dioxide carbonation in the aquifer.

[0068] In one embodiment of a quantification process 1000 according to the invention, the latter may include a step for correcting the elemental ratios of Helium, Xenon, and Argon calculated from the rare gas isotopic composition of the charged tracing parameters 140. Indeed, during the dissolution of one or more mineral phases from igneous rocks, divalent cations such as, in particular, Mg 2+ Fe 2+ and / or That 2+ will form. The dissolution of these mineral phases can induce an increase in the aqueous phase of certain isotopes of Helium, Argon, and Xenon, and will therefore affect the calculated isotopic ratios of the noble gases. This increase of certain noble gas isotopes in the aqueous phase will primarily impact the isotopic ratios of Argon, one of whose isotopes ( 40Ar) is most abundantly produced in mineral matrices and preserved in these matrices at low temperatures (<200°C). The correction step can therefore include determining the isotopic ratios of the increasing noble gases and calculating a linear function between the divalent cation concentration, the CO2 concentration, and the isotopic ratios of the non-increasing noble gases, preferably those not produced by radioactive decay in the mineral phases. From this relationship, the correction step can be configured to calculate corrected isotopic ratios based on the isotopic ratios that characterize an increase in the quantity of a given noble gas in the aquifer.

[0069] According to another aspect, the invention relates to a non-transient computer-readable medium storing executable instructions which, when executed by a processor of a computer device, implement a quantization process 1000 according to the invention.

[0070] For the purposes of the present invention, a computer-readable medium may include any instrument or aggregation of instruments capable of storing data and / or instructions for a specified period. Computer-readable media may include, for example, without limitation, storage media such as a direct-access storage device (e.g., a hard disk drive or floppy disk drive), a sequential-access storage device (e.g., a floppy disk drive), a compact disc, a CD-ROM, a DVD, RAM, ROM, electrically erasable programmable read-only memory (EEPROM), and / or flash memory; as well as communication media such as wires, optical fibers, microwaves, radio waves, and other electromagnetic and / or optical media; and / or any combination thereof.

[0071] Preferably, the non-transient computer-readable medium, when executed by a processor, can implement the 1000 quantization process according to the invention.

[0072] According to a third aspect, the invention relates to a computer device for the quantification of a fraction of carbon dioxide from a single-phase liquid mixture, said computer device comprising a processor configured to implement a quantification process according to the invention.

[0073] For the purposes of this disclosure, a computer device according to the invention may include any instrument or aggregate of instruments that can be used to calculate, classify, process, transmit, receive, retrieve, generate, store, display, detect, record, reproduce, manage or use any form of information, data or data.

[0074] For example, a computing device according to the invention may be a personal computer, a server, a network storage device, or any other suitable device, and may vary in size, shape, performance, features, and price. The computing device according to the invention may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and / or other types of non-volatile memory. Additional components of the information processing system may include one or more disk drives, one or more network ports for communication with external devices, and various input / output (I / O) devices, such as a keyboard, mouse, and video monitor.The information processing system may also include one or more buses that can be used to transmit communications between the various hardware components.

Claims

Method for quantifying (1000) a fraction of carbon dioxide from a liquid monophasic mixture, composed of at least water and carbon dioxide, injected into an aquifer reservoir, said method (1000) being implemented by a computer device and comprising: a step of determining, at a second instant, tracing parameters, from a sample of the liquid monophasic mixture injected into the aquifer reservoir, said sample comprising a mixture composed of water from the aquifer and a quantity of the liquid monophasic mixture injected at a first instant, said tracing parameters comprising: a carbon dioxide concentration, a carbon isotopic signature, an isotopic and elemental composition in rare gases comprising at least Xenon, Argon and Helium, a step of loading, from a data memory, the tracing parameters, a comparison step (160),by a processor of said computer device, tracing parameters to reference injection parameters determined in the mixture composed of water and a quantity of carbon dioxide injected at the first instant, said reference injection parameters comprising: an initial concentration of carbon dioxide, an initial isotopic signature of carbon, an initial isotopic and elemental composition of noble gases, comprising at least Xenon, Argon and Helium, the comparison step (160) further comprising a calculation of the elemental ratios of Helium, Xenon and Argon, and when the comparison step (160) indicates a variation (160-Y) of the elemental ratios of noble gases between the tracing parameters and the reference injection parameters, the process comprises: a determination step (170), by the processor, of a quantity of carbon dioxide lost including: a calculation of the isotopic ratios of Helium,Xenon and Argon tracing parameters and reference injection parameters, a calculation of the variation of the carbon isotopic signature of the tracing parameters with respect to the reference injection parameters, an estimate of the amount of carbon dioxide lost, from a mathematical law that relates said amount to the variation of at least one elemental ratio of Helium, Argon and / or Xenon as a function of the calculated isotopic and elemental ratios, and the variation of the carbon isotopic signature, a calculation step (200), by the processor, of the amount of carbon dioxide mineralized from a mathematical law that relates the estimate of the carbon dioxide lost and the amount of carbon dioxide injected at the first instant. A quantification method (1000) according to claim 1, wherein the comparison step (160) further comprises a calculation of the carbon dioxide to helium ratio of the reference tracing parameters and injection parameters, and wherein when the comparison step (160) indicates: a preferential decrease in Xenon, a decrease in the carbon dioxide to helium ratio, that the isotopic ratios of Argon and Helium of the calculated reference tracing parameters and injection parameters are unchanged, the variation in the elemental ratio taken into account in the estimation of a quantity of carbon dioxide lost (170-1) corresponds to the Xenon to Helium ratio. A quantification method (1000) according to claim 2, wherein the estimation (170-1) of the quantity of carbon dioxide lost, denoted ,is calculated according to the following mathematical law: , Or is the ratio between a mass of active rock in the reservoir and a given volume of water, said ratio being preferably calculated according to the following equation: , with A quantification method (1000) according to claim 1, wherein the comparison step (160) further comprises a calculation of the carbon dioxide to helium ratio of the tracing parameters and the reference injection parameters, and wherein when the comparison step (160) indicates: a preferential decrease in helium, that the isotopic ratios of argon and xenon of the calculated tracing parameters and the reference injection parameters are unchanged, said method (1000) comprises an adjustment step (180) of the elemental composition of helium of the tracing parameters. A quantification method (1000) according to any one of claims 1 or 4, wherein the comparison step (160) further comprises a calculation of the carbon dioxide to helium ratio of the tracing parameters and the reference injection parameters, and wherein when the comparison step (160) indicates: a preferential decrease of helium, an increase in the carbon dioxide to helium ratio, a decrease in the isotopic ratios of argon and xenon of the tracing parameters with regard to the corresponding ratios of the reference injection parameters, the determination step (170) comprises an estimation of a second quantity of carbon dioxide lost (170-2) from a second mathematical law which relates said quantity to the elemental ratio of xenon to helium. A quantification method (1000) according to claim 5, wherein the estimation of the second quantity of carbon dioxide lost (170-2), denoted is calculated according to the following second mathematical law: , Or , with ; the concentrations of Xenon and Helium measured at the first instant in the injected mixture, and ; the concentration of this same species measured at the second time step in a sample taken from the aquifer reservoir and the Fick diffusion coefficients of the corresponding species. A quantification method (1000) according to any one of claims 1 to 6, wherein the tracing parameters and the reference injection parameters respectively comprise a divalent cation concentration containing at least Mg 2+ Fe 2+ and / or That 2+ and an initial concentration of divalent cations containing at least Mg 2+ Fe 2+ and / or That 2+said process includes a verification step (150) of a dissolution in which said divalent cation ratios are calculated and when at least one divalent cation ratio indicates an increase in the concentration of said cation of the tracing parameters, the comparison step (160) is implemented. A quantification method (1000) according to any one of claims 1 to 7, said method (1000) comprising a step of determining (110-1), at the first instant, a carbon dioxide concentration, a carbon isotopic signature, an isotopic and elemental composition in rare gases comprising at least Xenon, Argon and Helium of a single-phase liquid mixture composed at least of water and a quantity of carbon dioxide to be injected. A quantification method (1000) according to any one of claims 1 to 8, said method (1000) comprising a step of determining (110-2) a carbon dioxide concentration, a carbon isotopic signature, and an isotopic and elemental composition of rare gases comprising at least Xenon, Argon, and Helium of an aquifer reservoir. A quantification method (1000) according to any one of claims 1 to 9, said method (1000) comprising an injection step (120), at a first instant, into the aquifer reservoir of a single-phase liquid mixture composed of at least water and carbon dioxide. Quantification method (1000) according to claim 10, said method (1000) comprising a sampling step (130) at a second time of a fraction of carbon dioxide from the single-phase liquid mixture. Non-transient computer-readable medium storing executable instructions which, when executed by a processor of a computing device, implement a method (1000) according to any one of claims 1 to 11. Computer device for the quantification of a fraction of carbon dioxide from a single-phase liquid mixture, said computer device comprising a processor configured to implement a method (1000) according to any one of claims 1 to 11.

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