Portable device for producing a gas sample from a solid sample

Abstract

The invention relates to a portable device for producing a gaseous sample from a solid sample, referred to as a sampler. The sampler comprises a sampling block and a conditioning block, fluidic connection means arranged to fluidly connect the sampling block and the conditioning block, and a laser source arranged to emit a laser beam capable of generating calcination and / or combustion of a portion of the solid sample. The sampling block includes a chamber, referred to as the receiving chamber, for receiving calcination / combustion gases from the solid sample; said receiving chamber includes an opening in a wall of said receiving chamber intended to be positioned opposite the solid sample.The sampling unit comprises an optical head, coupled to the laser source, arranged to direct the laser beam through the aperture and to vary one axis of the laser beam so that the laser beam scans, at least partially, the aperture. The conditioning unit comprises a chamber, called the conditioning chamber, for receiving the calcination / combustion gases from the receiving chamber, and pneumatic and fluidic connection means arranged to filter and homogenize the calcination / combustion gases in the conditioning chamber. Figure 5.

Description

Title of the invention: Portable device for producing a gaseous sample from a solid sample. Technical field

[0001] The present invention belongs to the field of the preparation of gaseous samples from solid samples.

[0002] The invention relates, in particular, to the preparation of gaseous samples from solid samples, mainly minerals containing carbon and / or oxygen.

[0003] The invention relates, in particular, to the preparation of gaseous samples intended to be examined by isotopic analysis, for example by mass spectrometry or optical spectroscopy.

[0004] The present invention relates, more particularly, to the preparation of gaseous samples, from rock samples containing carbonates, intended to be examined by isotopic analysis of carbon and / or oxygen. State of the art

[0005] Prior art knows of the preparation of gaseous samples, particularly for the isotopic analysis of solid samples, especially mineral samples, by chemical treatment. A ground fragment of the sample to be analyzed is chemically treated by dissolution in an acid, typically orthophosphoric acid, or by heating. This reaction produces carbon dioxide, which is then injected into a mass spectrometer for isotopic analysis of carbon and / or oxygen.

[0006] One drawback of this technique is that it requires collecting a fragment of the sample to be analyzed in the field and then sending it to a laboratory to be ground and prepared, particularly through treatments aimed at removing organic matter, before being chemically treated. These steps introduce a delay of one to several weeks between sampling and results, making the analysis time-consuming and costly in terms of consumables and human resources.

[0007] Another drawback of this technique is that it is sample-dependent. It requires the intervention of a geology expert to develop the analysis protocol and choose the acid based on their assessment of the rock's nature. It is common to perform several treatments given the uncertainty related to the rock's composition.

[0008] The prior art also contains known methods for preparing gaseous samples for isotopic analysis of solid samples, in particular samples Minerals are analyzed by laser ablation. The most common technique for this type of analysis is inductively coupled plasma mass spectrometry (ICP-MS). This technique is implemented in a device comprising an ablation laser coupled to a mass spectrometer. The lasers used in this type of device are UV-emitting lasers. These include excimer lasers or solid-state lasers triggered with frequency tripling or quadrupling, primarily Nd:YAG or Nd:YV04, or femtosecond lasers.

[0009] As with chemical treatment, a disadvantage of laser ablation lies in the fact that it is necessary to take a fragment of the sample to be analyzed from the field and send it to the laboratory so that it can be prepared for analysis; these techniques use devices whose size and weight make any movement on site impossible.

[0010] An additional drawback inherent in gaseous sample preparation techniques for isotopic analysis by laser ablation is related to the phenomenon of isotopic fractionation of elements. This fractionation is due to recombination and variations in the recovery rate, which leads to a change in the isotopic ratio in the gaseous sample compared to the actual isotopic ratio of the solid sample. This results in biased isotopic analysis results.

[0011] Another drawback of state-of-the-art gas sample preparation techniques is that the isotope extraction reaction is not entirely efficient with certain lasers. This lack of extraction efficiency is detrimental because it can induce isotopic fractionation and distort the analyses.

[0012] Another drawback of state-of-the-art gas sample preparation techniques is their matrix dependence. The preparation is not identical for every solid sample but varies from one sample type to another due to matrix effects. This drawback necessitates the use of correction factors during isotopic analysis of an element.

[0013] We also know in the prior art of document FR1907289 describing a device for the preparation of gaseous samples from solid samples using laser beams whose instantaneous power density and irradiance are significantly lower, and the interaction time of the laser beam with the solid sample is significantly longer, than those of the beams emitted by the excimer lasers, triggered solid-state lasers or femtosecond lasers described previously.

[0014] Such devices allow the preparation of gaseous samples that are insensitive, or only slightly sensitive, to matrix effects.

[0015] Furthermore, the preparation of gaseous samples using such devices does not cause isotopic fractionation or causes negligible isotopic fractionation.

[0016] Finally, gaseous samples obtained or prepared by such devices can be analyzed directly without resorting to a gas chromatography step before isotopic analysis as is the case with ablation lasers.

[0017] One drawback of this type of device is its bulky and cumbersome size. Although "transportable" in the sense that it can be moved, it is not portable or handheld. Its use is intended for fixed field laboratories or temporary installations, such as tents or containers, or for locational sites such as buildings near the analytical laboratory.

[0018] However, the sampling sites (for example, rocks) may be difficult to access, may only be accessible on foot, may require several hours of walking, and / or may not be known in advance. This type of device cannot be worn and, a fortiori, cannot be transported to the sampling sites.

[0019] Another drawback of this type of device is that it is necessary to collect the rock samples on site and then transport the collected solid samples to the device (field laboratory, temporary installation, or buildings housing the device) for gas sample preparation. The collected solid samples are heavy and therefore need to be transported to the device. Furthermore, it is necessary to collect a large number of samples in order to have several samples of the same type to repeat, reproduce, and verify the results, and also to have a panel of distinct samples (geologically and / or geographically).

[0020] One object of the invention is to provide a device for producing a gaseous sample from a solid sample: • allowing for the overcoming of at least one of the drawbacks of state-of-the-art gas sample preparation techniques, and / or • portable and / or can be carried by a single person without any particular or significant effort, and / or • enabling the production of gas samples directly on site, and / or • not requiring the transport of solid samples, and / or • allowing for the preparation of a large number of gaseous samples directly on site, and / or • enabling the production of gaseous samples regardless of the morphology or topology of the solid samples, and / or • enabling the analysis of solid samples under challenging conditions and / or in locations or areas where the collection of solid samples is not possible, or difficult, and / or • offering control, directly on site and / or after sampling, of the gaseous sample produced, and / or • enabling the collection and conditioning, for example in terms of homogeneity, purity and preservation, of gaseous samples directly on site, and / or • enabling more efficient gas production and / or enabling the production of a larger quantity of gas during each withdrawal. Description of the invention

[0021] For this purpose, a portable device for producing a gaseous sample from a solid sample, called a sampler, is proposed.

[0022] Preferably, the gaseous sample comprises gaseous CO2.

[0023] Preferably, the solid sample comprises minerals.

[0024] Preferably, the minerals comprise carbon and / or oxygen.

[0025] Preferably, but not limitingly, the solid sample comprises or is made up of carbonates.

[0026] Preferably, the gaseous sample is intended for isotopic analysis of carbon (δ13C) and / or oxygen (δ18O).

[0027] The sampler comprises a sampling block and a conditioning block.

[0028] Preferably, the sampling block and the conditioning block are physically and / or spatially distinct.

[0029] The sampler includes fluidic connection means.

[0030] The fluidic connection means are arranged to fluidly connect the sampling block and the conditioning block.

[0031] The sampler includes a laser source.

[0032] The laser source is arranged to emit a laser beam capable of generating calcination and / or combustion of a part of the solid sample.

[0033] The sampling block includes a chamber, called the receiving chamber.

[0034] The receiving chamber is intended to receive calcination / combustion gases from the solid sample.

[0035] The receiving chamber includes a wall.

[0036] The wall is intended to be carried opposite the solid sample.

[0037] The receiving chamber includes an opening made in the wall.

[0038] Preferably, the wall and / or the opening of the receiving chamber is intended to be opposite or facing the part of the sample intended to be calcined and / or combusted.

[0039] The sampling block includes an optical head.

[0040] The optical head is coupled to the laser source.

[0041] The optical head is arranged to direct the laser beam through the aperture.

[0042] The optical head is arranged to vary one axis of the laser beam so that the The laser beam sweeps, at least partially, across the opening.

[0043] The optical head can be defined as being arranged so that the axis of the laser beam sweeps, at least in part, the aperture.

[0044] Preferably, the optical head is arranged to vary an axis of the laser beam so that the laser beam sweeps, at least in part, the aperture or the surface of the aperture or the surface described by the aperture or the surface circumscribed by the aperture or by the edges of the aperture.

[0045] Preferably, the optical head is arranged to vary an axis of the laser beam so that the laser beam sweeps, for example only in part or in whole, the opening or the surface of the opening or the surface described by the opening or the surface circumscribed by the opening or by the edges of the opening.

[0046] The conditioning block includes a chamber, called the conditioning chamber.

[0047] The conditioning chamber is intended to receive the calcination / combustion gases from the receiving chamber.

[0048] Preferably, the conditioning chamber is intended to receive the calcination / combustion gases, coming from the receiving chamber, having passed, by the fluidic connection means, from the receiving chamber to the conditioning chamber.

[0049] The conditioning block includes pneumatic means and fluidic connections.

[0050] Pneumatic and fluidic connection means are arranged to filter and homogenize the calcination / combustion gases in the conditioning chamber.

[0051] Preferably, the sampler and / or the receiving chamber and / or the opening is arranged to form, with the solid sample and / or the surface of the sample and / or with the part of the solid sample, a closed or delimited or airtight volume.

[0052] Preferably, the enclosed or delimited volume is intended to receive combustion and / or calcination gases.

[0053] Preferably, the laser beam according to the invention: - is arranged to heat, at a given or considered impact zone, the solid sample to a temperature above 600 °C and / or below 1100 °C, and / or - is incapable of extracting material from the solid sample by laser ablation.

[0054] It can be understood by "a laser beam capable of generating calcination and / or combustion of a part of the solid sample": a laser beam capable of generating mainly or predominantly or solely calcination and / or combustion of a part of the solid sample.

[0055] Laser ablation is understood to mean the extraction of material from the solid sample directly caused by the interaction between the laser and the solid sample. This extraction is caused directly by the laser, for example, by the formation of a laser plasma, by spraying, by evaporation or by explosive evaporation, by a photoablative effect, or by mechanical shock.

[0056] A person skilled in the art will understand that evaporation, generated by laser ablation, is meant to be the change of matter from the solid sample from a solid state to a gaseous state (sublimation).

[0057] Preferably, according to the invention, the laser beam, at the impact zone, is not capable of generating laser ablation, that is to say, it is not capable of modifying the structure of the solid sample and / or extracting material from the solid sample other than through the calcination reaction and / or combustion that it induces at the given impact zone on the surface of the solid sample. The beam can be arranged so as to present an irradiance such that it causes heating of the given impact zone on the surface of the solid sample to a temperature above 600 °C and / or to a temperature below 1100 °C, preferably to a temperature close to or equal to 900 °C.

[0058] Preferably, according to the invention, an optical / electrical efficiency of the laser source can be greater than or equal to 30%.

[0059] Preferably, the optical / electrical efficiency of the laser source is greater than or equal to 40%.

[0060] According to the invention, the laser source can operate at low voltage and high current. Low voltage is understood to mean a voltage value less than or equal to 50 volts and greater than or equal to 1 V. High current is understood to mean a current value greater than or equal to 1 ampere and less than or equal to 50 A.

[0061] The laser source may comprise or consist of a laser diode.

[0062] According to the invention: - The laser source can be a laser diode, or - the laser source can be an optically pumped doped fiber.

[0063] The laser source can be arranged to emit a laser beam with a wavelength greater than or equal to 0.3 pin and / or less than or equal to 5 pm.

[0064] The advantage of using a laser beam arranged to emit a laser beam capable of generating calcination and / or combustion, and preferably a laser beam incapable of extracting material from the solid sample by laser ablation, is: - to obtain insensitive gaseous samples that do not exhibit matrix effects, and / or - to prepare gaseous samples without prior preparation, i.e., without a cleaning step aimed at removing surface organic pollution, and / or - to prepare gaseous samples with a reaction efficiency of 100%, or close to 100%, and / or - to prepare gas samples directly on site, and / or - to obtain directly analyzable gaseous samples, that is, without resorting to a gas chromatography step before analysis, particularly before isotopic analysis, and / or - to allow isotopic analysis not requiring the use of correction factors when determining the isotopy of an element, and in particular of carbon.

[0065] The sampler may include an optical fiber for the propagation of the laser beam between the laser source and the optical head.

[0066] The optical head can be coupled to the laser source by the optical fiber and / or the laser fiber can couple the laser source to the optical head.

[0067] The laser beam emitted by the laser diode can be injected into the optical fiber for the propagation of the laser beam between the laser source and the optical head.

[0068] According to the invention, the diameter of a core of the optical fiber can have a value: - greater than or equal to 2 pm, preferably 5 pm and preferably greater than or equal to 50 pm, and / or - less than or equal to 800 pm.

[0069] Preferably, a numerical aperture of the optical fiber can be greater than or equal to 0.1 and / or less than or equal to 0.5.

[0070] The numerical aperture of optical fiber can typically be 0.22.

[0071] Preferably, the conditioning block and the sampling block are separate. and / or separate and / or isolable and / or controlled, preferably separately and / or individually and / or distinctly, particularly via fluidic connection means and / or pneumatic means. Thus, the environment and / or atmosphere and / or pressure of the receiving chamber and the chamber of packaging is controllable and / or controlled individually and / or independently.

[0072] The advantage of using a sampling block and a conditioning block, and / or using a receiving chamber and a conditioning chamber, preferably able to communicate or be fluidly connected and fluidly isolated, and / or using a sampling block separate from the conditioning block, and / or a receiving chamber separate from the conditioning chamber, is: - to ensure the homogenization, control, filtering and integrity of the collected gas, and / or - to allow for a reduction in the mass of samples collected and transported, and / or - to allow a significant number of samples during the same sampling campaign, and / or - to provide a reduced sampling time, in particular due to the separation between the sampling step (combustion / calcination during irradiation of the sample with the laser beam) and the conditioning step (homogenization, control, filtering and conditioning of the sampled gas); the conditioning step requiring more time than the time necessary to carry out the sampling step according to the invention, and / or - simplify the work and / or reduce user handling, and / or - to automate the entire gas sample preparation process.

[0073] The advantage of using a laser beam angle variation to scan, at least partially, the aperture is: - to produce gaseous samples more efficiently, and / or - to produce a larger quantity of gas with each sampling, and / or - to reduce the sampling failure rate, and / or - to collect a sufficient quantity of gas (corresponding to the minimum quantity required for subsequent gas analysis), and / or - to collect a sufficient quantity of carbon dioxide (CO2) contained in the gaseous sample taken.

[0074] Preferably, the laser source and / or optical head is arranged so that the laser beam has an irradiance of less than 5 MW / cm2 at the given or considered impact zone on a surface of the solid sample.

[0075] Preferably, the laser beam at the output of the laser source may have a power less than or equal to 500 Watts (W), preferably a power less than or equal to 100 W.

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[0088] The laser beam output from the laser source can have a power greater than or equal to 1 W. Preferably, the laser beam has, at the given impact zone on the surface of the sample, an irradiance less than or equal to 1 MW / cm2, more preferably 500 kW / cm2, more preferably 100 kW / cm2, more preferably 50 kW / cm2 and most preferably of all an irradiance less than or equal to 20 kW / cm2. Preferably, the laser beam has, at the given impact zone on the surface of the sample, an irradiance greater than or equal to 10 kW / cm2. According to the invention, the laser source can be arranged to emit in the following mode: - continuous or quasi-continuous, and / or - relaxed impulse, and / or - chopped. The laser source, operating for example in relaxed pulsed and / or chopped mode, can be arranged to emit for a duration greater than or equal to 10 microseconds (ps), preferably 50 ps, ​​more preferably 100 ps, ​​even more preferably 500 ps and most preferably greater than or equal to 1 second. Preferably, the laser source is arranged to emit in continuous or quasi-continuous mode. According to the invention, the laser source is preferably incapable of emitting in triggered mode. Preferably, the receiving chamber also includes an optical window provided in a wall of the receiving chamber opposite the wall of the receiving chamber intended to be brought opposite the solid sample. Preferably, the optical window is arranged to isolate, particularly fluidically, the laser source and / or the optical head from the receiving chamber. Preferably, the optical head is positioned opposite the optical window. Preferably, the optical head is positioned upstream of the receiving chamber, relative to the optical path of the laser beam. The term "optical path of the laser beam" can be understood as: the path of the optical path of the laser beam from the laser source to or from: - the optical head, and / or - the optical window, and / or - the opening, and / or - the optical sample. Preferably, the optical head is also arranged to direct the laser beam: - through the optical window, and / or - through the opening.

[0089] Preferably, the sampler includes means for beam shaping arranged to shape the laser beam emitted by the laser source.

[0090] The shaping means may be included in the optical head or disposed outside the optical head and / or may constitute an element of the sampler separate from the optical head.

[0091] Preferably, the pneumatic and fluidic connection means are arranged to, in addition: - to vacuum-seal the conditioning chamber, and / or - transfer the conditioned gaseous sample into a transport vial.

[0092] Preferably, the pneumatic and fluidic connection means and the fluidic connection means are arranged to, in addition, vacuum the receiving chamber.

[0093] Preferably, the calcination and / or combustion gases are drawn or pumped from and / or to the conditioning chamber (for example by suction or pumping, for example from the vacuum created in the conditioning chamber), preferably by means of or through the fluidic connection means.

[0094] Preferably, the calcination and / or combustion gases are drawn or pumped from and / or to the conditioning chamber by means of or by opening a controlled fluidic connection (for example a pneumatic valve) separating or arranged between the sampling chamber and the conditioning chamber.

[0095] Preferably, the optical head is arranged to print: - a rotational movement around the axis of the laser beam, preferably around the laser beam originating from the laser source, and / or - a precessional movement around the axis of the laser beam, preferably around the laser beam originating from the laser source, and / or - a translational movement to the axis of the laser beam, preferably to the laser beam coming from the laser source.

[0096] According to the invention, the optical head is further arranged so that the laser beam scans the aperture. The optical head can also be arranged to impart a translational motion to the laser beam.

[0097] The optical head can be arranged, furthermore, so that the laser beam sweeps the aperture in a straight line or according to a translational movement.

[0098] In a particularly advantageous manner, the optical head is arranged so that the laser beam sweeps the aperture along and / or to impart a precession movement to the axis of the laser beam, preferably relative to an axis of rotation of the optical head.

[0099] Preferably, the optical head is arranged to: - rotate the laser beam axis around an axis of revolution of the aperture, and / or - to precess the axis of the laser beam relative to an axis of revolution of the aperture.

[0100] The advantage of using an optical head arranged to impart a rotational movement to the laser beam axis and / or to impart a precessional movement to the laser beam axis and / or to rotate the laser beam axis around an axis of revolution of the aperture and / or to precess the laser beam axis relative to an axis of revolution of the aperture is, by using a simple device and / or by using a reliable device and / or by using a robust device and / or by using a device requiring little maintenance and / or consuming little energy and / or obtaining faster sampling: - to produce gaseous samples more efficiently, and / or - to produce a larger quantity of gas with each sampling, and / or - to reduce the sampling failure rate, and / or - to collect a sufficient quantity of gas (corresponding to the minimum quantity required for subsequent gas analysis), and / or - to collect a sufficient quantity of carbon dioxide (CO2) contained in the gaseous sample taken.

[0101] Preferably, the optical head is arranged so that the axis of the laser beam is offset, preferably relative to the axis of revolution of the aperture, and parallel to the axis of revolution of the aperture.

[0102] In the present application, "off-center" may be understood to mean: a line (or axis) which does not have the same axis as a given or considered axis (or line) but which, preferably, is parallel to the given or considered line or axis.

[0103] Preferably, when the optical head is arranged so that the axis of the laser beam is offset from the axis of revolution of the aperture and parallel to the axis of revolution of the aperture, the optical head and / or the aperture and / or the sampler is arranged so that the axis of the laser beam and / or the axis of revolution of the aperture is parallel to the axis of revolution of the aperture and, preferably, does not intersect or pass through, at any time, the center (geometric or barycenter) or the middle of the aperture.

[0104] Preferably, the optical head is arranged so that the axis of the laser beam forms a non-zero angle with the axis of revolution of the aperture.

[0105] Preferably, when the optical head is arranged so that the axis of the laser beam forms a non-zero angle with the axis of revolution of the aperture, the optical head and / or the aperture and / or the sampler is arranged so that the axis of the laser beam and / or the axis of revolution of the opening intersects or passes through, at every instant, the center (geometric or barycenter) or the middle of the opening.

[0106] The optical head and / or the aperture and / or the sampler can be arranged to switch from: - a position in which the axis of the laser beam and / or the axis of revolution of the aperture is parallel to the axis of revolution of the aperture and, preferably, does not intersect or pass through, at any instant, the center (geometric or barycenter) or the middle of the aperture, towards - a position in which the axis of the laser beam and / or the axis of revolution of the aperture intersects or passes through, at any instant, the center (geometric or barycenter) or the middle of the aperture, and vice versa.

[0107] Preferably, the receiving chamber includes, on the outside of the wall of the receiving chamber intended to be brought opposite the solid sample, a sealing means.

[0108] Preferably, the sealing means extends around the opening.

[0109] Preferably, the sealing means is arranged to ensure sealing between the solid sample and the opening.

[0110] Preferably, the sealing means delimits or circumscribes the opening.

[0111] The sealing means may be attached, contiguous or delimit the opening.

[0112] The sealing means may be remote or distant, or not be attached, not be contiguous or not delimit, of the opening or a space may be present between the opening and the sealing means.

[0113] The receiving chamber may include, on the outside of the wall of the receiving chamber intended to be carried opposite the solid sample, a nozzle extending between the opening and the sealing means.

[0114] Preferably, the pneumatic and fluidic connection means and / or the fluidic connection means are arranged to inject an inert gas into the conditioning chamber and / or into the receiving chamber.

[0115] Thus, preferably, the conditioning chamber and / or the receiving chamber can be, preferably selectively, under vacuum or under an inert atmosphere. Preferably, the conditioning chamber and / or the receiving chamber can be, before receiving the combustion and / or calcination gases, under vacuum or under an inert atmosphere.

[0116] The calcination and / or combustion gases produced can be received in the receiving chamber maintained under vacuum or atmospheric pressure, in particular, and preferably, under an inert atmosphere.

[0117] Combustion and / or calcination gases may be received and / or produced under vacuum or under an inert atmosphere.

[0118] Preferably, the conditioning chamber includes at least one pressure sensor.

[0119] Preferably, the pressure sensor of the conditioning chamber is arranged to measure the pressure in the conditioning chamber.

[0120] Preferably, the receiving chamber includes at least one pressure sensor.

[0121] Preferably, the pressure sensor of the receiving chamber is arranged to measure the pressure in the receiving chamber.

[0122] Preferably, the receiving chamber includes at least one optical sensor.

[0123] Preferably, the optical sensor of the receiving chamber is arranged to detect a light pulse produced during the initiation of calcination and / or combustion of the solid sample.

[0124] Preferably, the receiving chamber further comprises an optical filter. Preferably, the optical filter is disposed or positioned in front of the optical sensor.

[0125] Preferably, the optical filter of the detection chamber is arranged to: - cut or block beams from laser radiation, and / or - retain or allow visible light to pass through, preferably only visible light.

[0126] Preferably, the conditioning block includes a CO2 measuring sensor.

[0127] Preferably, the CO2 measuring sensor is arranged to measure, in the conditioning chamber, the quantity of CO2 included in the calcination / combustion gases.

[0128] Preferably, the sampler includes a control unit.

[0129] Preferably, the control unit may include a processing unit.

[0130] Preferably, the sampler includes an operable and manipulable gun, preferably by an operator or user, with one hand, called a gun.

[0131] Preferably, the gun includes the sampling block and the conditioning block.

[0132] Preferably, the sampler includes a storage tank for the inert gas.

[0133] Preferably, the sampler includes a power supply.

[0134] Preferably, the sampler includes one or more carrying means.

[0135] Preferably, the carrying means are arranged to be carried by a user or operator.

[0136] Preferably, the carrying means include: - the inert gas storage tank, and / or - the power supply, and / or - the control unit.

[0137] Preferably, the control unit is arranged and / or programmed and / or configured to: - calculate and / or determine and / or control, based on measurement data from the pressure sensor in the receiving chamber and / or measurement data from the pressure sensor in the conditioning chamber: • the pressure reached after, or the overpressure generated by, calcination and / or combustion, particularly when the conditioning chamber and / or the receiving chamber is under vacuum before calcination and / or combustion, and / or • the pressure reached after evacuation of the receiving chamber and / or the empty conditioning chamber, for example during purging following the conditioning of a gaseous sample and / or during evacuation prior to sampling, and / or • the possible presence of leaks, and / or • also from measurement data from the CO2 sensor, the pressure and / or quantity of CO2 transferred into the conditioning chamber, for example in the case where it is initially under vacuum, and / or - to control, where applicable, based on measurement data from the pressure sensor in the receiving chamber and / or measurement data from the pressure sensor in the conditioning chamber and / or measurement data from the CO2 measurement sensor: • the means of fluidic connection, and / or • the laser source, and / or • the optical head, and / or • pneumatic and fluidic connection means, and / or • the conditioning chamber, preferably the components of the conditioning chamber that can be controlled, and / or • the reception room, preferably the elements of the reception room that can be ordered.

[0138] According to the invention, a method for producing a gaseous sample from a solid sample, referred to as the method, is also proposed.

[0139] Preferably, the process is implemented using a device for producing a gaseous sample from a solid sample.

[0140] Preferably, the method is implemented using the sampler according to the invention.

[0141] The process comprises the steps of: - emit a laser beam, from a laser source of said sampler, scanning, at least in part, an aperture of said sampler, - to generate calcination and / or combustion of a portion of the solid sample, by said laser beam, - to receive calcination / combustion gases, through the opening, into a receiving chamber of said sampler, - transfer the calcination / combustion gases from the receiving chamber into a conditioning chamber of said sampler, - filter and homogenize the calcination / combustion gases in the conditioning chamber.

[0142] Preferably, the sampler according to the invention is suitable, more preferably is particularly adapted, even more preferably is designed, and most advantageously is specially designed, for implementing the process of producing a gaseous sample from a solid sample according to the invention. Furthermore, any feature of the sampler according to the invention is directly applicable to the process of producing a gaseous sample from a solid sample according to the invention. Brief description of the FIGURES

[0143] The invention will be better understood upon reading the following description, given solely by way of non-limiting example and made with reference to the accompanying drawings in which: - Figures 1 to 3 are photographs taken from different angles of the sampler according to the invention held by the user's hand, - Figure 4 is a photograph of the carrying means according to the invention. - [Fig. 5] is a schematic representation of the sampler according to the invention, - Figure [Fig. 6] is a schematic representation, viewed from an angle, of the optical head of the sampler. - Figure 7 is a schematic top-view representation of the optical head of the sampler, - [Fig.8] is a photograph of the area of ​​the surface of a solid sample that has been calcined / combusted by the sampler.

[0144] It is understood that the embodiments described below are in no way limiting. In particular, variants of the invention may be conceived comprising only a selection of the features described below, isolated from the other features described, if this selection of features is sufficient to confer a technical advantage or to differentiate the invention from the prior art. This selection includes at least one preferably functional feature without structural details, or with only a portion of the structural details if this part alone is sufficient to confer a technical advantage or to differentiate the invention from the prior art.

[0145] In particular, all the variants and embodiments described are combinable with each other if there is no technical obstacle to this combination.

[0146] In the figures and in the rest of the description, elements common to several figures retain the same reference. Detailed description of the FIGURES

[0147] With reference to FIGURES 1 to 5, an example of a non-limiting embodiment of the portable device for producing a gaseous sample 1 from a solid sample 99, called sampler 1 according to the invention, is described.

[0148] With reference to [Fig.5], the sampler 1 includes a sampling block 2 and a conditioning block 3. The sampler 1 includes fluidic connection means 4. The fluidic connection means 4 are arranged to connect, fluidly, the sampling block 2 and the conditioning block 3.

[0149] The sampler 1 includes a laser source 5. The laser source 5 is arranged to emit a laser beam capable of generating calcination and / or combustion of a part of the solid sample 99.

[0150] The effects and advantages related to the use of a laser source and / or beam according to the invention have been detailed previously.

[0151] The sampling block 2 includes a chamber or enclosure 21, referred to as the receiving chamber 21. The receiving chamber 21 is intended to receive calcination / combustion gases from the solid sample 99.

[0152] The receiving chamber 21 includes an opening 22 formed in a wall 23 of the receiving chamber 21. The opening 22 and the wall 23 are intended to be brought opposite the solid sample 99.

[0153] The sampling block 2 includes an optical head 6. The optical head 6 is coupled to the laser source 5.

[0154] The optical head 6 is arranged to direct the laser beam towards and through the aperture 22. The optical head 6 is further arranged to vary the axis of the laser beam so that the laser beam sweeps, at least in part, through the aperture 22.

[0155] The effects and advantages related to scanning at least part of the aperture with the laser beam have been detailed previously.

[0156] The conditioning block 3 comprises a chamber or enclosure 31, referred to as the conditioning chamber 31. The conditioning chamber 31 is intended to receive the calcination / combustion gases from the receiving chamber 21. The calcination / combustion gases flow or pass through from the receiving chamber 21 to or up to the conditioning chamber 31 through or via the fluidic connection means 4.

[0157] The conditioning block 3 includes pneumatic and fluidic connection means 7, denoted MPCF 7. The MPCF 7 are arranged, among other things, to filter and homogenize the calcination / combustion gases in the conditioning chamber 31.

[0158] The effects and benefits associated with the use of a sampling block 2, and / or a receiving chamber 21, separate from the conditioning block 3, and / or the conditioning chamber 31 have been detailed previously.

[0159] According to the non-limiting embodiment, the laser source 5 is a fiber-optic power diode 5. The laser diode 5 has a power of 45W according to the non-limiting embodiment.

[0160] The laser source 5 emits at a wavelength greater than or equal to 0.3 pm and less than or equal to 5 pm. The laser diode emits at a wavelength of 945 nm according to the non-limiting embodiment.

[0161] According to the embodiment, the optical head 6 is coupled to the laser source 5 by means of an optical fiber 61. The optical fiber has a fiber core diameter of 100 pm.

[0162] The sampler 1 also includes one or more filters, arranged to filter the gases injected into the sampler 1 (for example combustion and / or calcination gases and / or inert gas).

[0163] The sampler also includes one or more sensors or probes arranged to measure gas pressure and / or species concentration (in particular CO2 but not exclusively) and / or one or more optical sensors 15.

[0164] The sampler 1 includes a control unit 14. The control unit 14 is arranged and / or programmed and / or configured to - calculate and / or determine and / or control, from the measurement data from the sensor(s), control and / or command and / or verification and / or safety data, and / or - to control, where appropriate from measurement data from the sensor(s), one, several or all of the elements, preferably one, several or all of the elements capable of being controlled, of the sampler 1.

[0165] According to an advantageous embodiment, and with reference to FIGURES 1 to 3, the sampler 1 includes a gun 111 that can be operated and manipulated with one hand by the user.

[0166] The sampling block 2 and the conditioning block 3 are included in the gun 111. As illustrated in the photographs, the gun 111 is handled and held The 111 gun can be operated with one hand without any particular effort. It measures approximately 28 cm in height, 10 cm in width, and 33 cm in length. The 111 gun weighs approximately 3 kg. Therefore, the user of the sampler 1 can move freely and perform sampling without restriction.

[0167] The advantage of the gun 111, combined with the presence of a separate conditioning block 3 and receiving block 2, is to allow the user / operator to collect the calcination and / or combustion gases, then choose another sampling area in the same location on site (without moving) and / or move to another sampling location (on site) while the sampled gases are being conditioned in the conditioning block 3 by the sampler 1.

[0168] With reference to FIGURES 6 and 7, optical head 6 is illustrated.

[0169] According to the non-limiting embodiment, the optical head 6 comprises means laser beam shaping means 62. The shaping means 62 are arranged to shape the laser beam emitted by the laser source 5.

[0170] The shaping means 62 are a telescope 62 according to the non-limiting embodiment. By way of non-limiting example, the example mentioned being linked to the particular dimensions and configuration of the non-limiting embodiment of the sampler 1, which can be adapted by those skilled in the art according to the objective sought, the shaping means 62 include a first collimating lens having a focal length of 25 mm. The shaping means 62 include a second lens having a focal length of 50 mm. The shaping means 62 therefore provide a magnification of 2 according to the embodiment.

[0171] The laser beam size at the given impact zone on the surface of sample 99 is on the order of a few hundred micrometers (pm). According to the non-limiting embodiment, the laser beam size at the given impact zone on the surface of sample 99 is on the order of 200 pm. This allows for a localized analysis of the solid sample 99.

[0172] The laser source 5 and the optical head 6, in particular the shaping means 62, are arranged so that the laser beam has an irradiance of less than 5 MW / cm2 at the level of a given impact zone on the surface of the solid sample 99.

[0173] As described in detail previously in the application, the laser source 5, or the combination of the laser source 5 and the optical head 6, according to the invention, is not capable of generating laser ablation of the irradiated area of ​​the solid sample 99. The laser source 5, or the combination of the laser source 5 and the optical head 6, according to the invention, generates only calcination and / or combustion of the solid sample 99.

[0174] With reference to FIGURES 6 and 7, the optical head 6 is arranged to put rotation to the axis of the laser beam, and / or put precession to the axis of the laser beam.

[0175] According to the embodiment, the optical head 6 is arranged to rotate the axis of the laser beam around an axis of revolution of the aperture 22.

[0176] However, it is also provided according to the invention that the optical head 6 is arranged to put the axis of the laser beam in precession relative to the axis of revolution of the aperture 22. A simple adaptation of the embodiment of the optical head 6 which will be described, consisting of inclining the axis of the laser beam relative to the axis of revolution of the aperture 22, will allow a person skilled in the art to implement this alternative.

[0177] In this case, the axis of the laser beam forms a non-zero angle with the axis of revolution of the aperture 22. The axis of the laser beam will have a constant point of intersection with the axis of revolution of the aperture 22. By way of non-limiting example, the point of intersection of the axis of the laser beam with the axis of revolution of the aperture 22 could be the center, the center of symmetry or the barycenter of the aperture 22.

[0178] According to the embodiment, and with reference to FIGURES 6 and 7, the end of the optical fiber 61 is fixedly mounted on the shaping means 62.

[0179] The optical head 6 includes a laser beam rotation device 64.

[0180] According to the embodiment, the rotation device 64 is arranged to rotate the shaping means 62.

[0181] The shaping means 62 form a cylinder 62 according to the embodiment. The end of the optical fiber 61, coming from the laser source 5, is connected and / or mounted on a connector or adapter 63. The adapter 63 is mounted and / or connected and / or fixed on the shaping means 62.

[0182] An axis of revolution of the adapter 63 and / or an axis of revolution of the optical fiber 61 is offset with respect to and parallel to the axis of revolution of the shaping means 62 and / or to the axis of rotation of the shaping means 62.

[0183] The axis of rotation of the shaping means 62 is aligned and / or coincides with the axis of revolution of the opening 22. The axis of revolution of the shaping means 62 coincides with the axis of rotation of the shaping means 62.

[0184] The axis of the optical beam is offset from and parallel to the axis of revolution of the shaping means 62 and / or to the axis of rotation of the shaping means 62. Thus, the irradiated area 991 of the solid sample 99 describes or forms a circle 991 or an arc of a circle 991 as illustrated in [Fig.8].

[0185] The shaping means 62 are arranged to be rotated, preferably endlessly, by means of a roller 632 in contact with the shaping means 62. The roller 632 is driven by a motor 633, a micro stepper motor 633 according to the embodiment.

[0186] According to the embodiment, the rotation device 64 includes a limit switch detection means 65. The limit switch detection means 65 allows a reference rotation position to be defined or detected.

[0187] The optical head 6, rotation device 64 according to the non-limiting embodiment, can be arranged to rotate the axis of the laser beam: - continuously, for example at a given or predefined rotational speed, or - step-by-step, by successive increment, for example by successive increment of a given or predefined angle of rotation, as a non-limiting example of an angle of rotation between 15 and 30°.

[0188] By way of non-limiting examples, and with reference to [Fig.5], the optical head 6 is arranged outside the receiving chamber 2. Such an arrangement makes it possible to limit the size of the receiving chamber 2. The volume of the receiving chamber 2 is thus reduced and the control of its atmosphere is improved.

[0189] Receiving chamber 2 includes an optical window 24.

[0190] The optical head 6, in particular an output face of the optical head 6, is arranged in vis-à-vis optical window 24.

[0191] The optical window 24 is provided in a wall of the receiving chamber 2 which is opposite the wall 23 of the receiving chamber intended to be brought opposite the solid sample 99.

[0192] The laser beam, coming from the optical head 6, therefore propagates through the optical window 24, then into the receiving chamber 21, then through the aperture 22 to the solid sample 99.

[0193] The receiving chamber 2 includes, on the outside of the wall 23 intended to be brought opposite the solid sample 99, a sealing means 10 extending around the opening 22. The sealing means 10 is arranged to ensure a seal between the solid sample 99 and the opening 22. The seal is ensured when the sampler 1, in particular the sealing means 10, is brought into contact with the solid sample 99. The sealing means 10 is an O-ring 10 according to the non-limiting embodiment. A person skilled in the art will know how to adapt the sealing means 10 to the shape of the opening 22 and / or to the size of the opening 22 and / or to the size of the sampler and / or to the shape of the sampler 1.

[0194] The sealing means 10 also allows gaseous samples to be taken from any surfaces. The sampler therefore allows gaseous samples to be taken from any type of solid sample 99, without the surface of the latter necessarily being flat.

[0195] The sealing means 10 also allows, once the surface of the solid sample 99 is in contact with the sealing means 10, the surface of the sample solid 99, located in the area of ​​the surface of the solid sample 99 delimited by the sealing means 10, is also under vacuum.

[0196] According to the non-limiting embodiment, and with reference in particular to [Fig. 3], the sampler 1 comprises a nozzle 16 projecting from the wall 23, intended to be positioned opposite the solid sample 99. The nozzle 16 is fixed around the opening 22, on the contour of the opening 22, or at a distance from the contour of the opening 22. The nozzle 16 circumscribes and / or delimits the opening 22. By way of non-limiting example, the nozzle 16 has a cylindrical shape. The sealing means 10 is mounted at the end of the nozzle 16 (in particular at the end of the nozzle located on the side of the nozzle opposite the wall 23).

[0197] According to the non-limiting embodiment, the sampler 1 comprises one or more light-emitting means 17, particularly in the visible range. The light-emitting means 17 are arranged to illuminate the solid sample 99 when the sampler is near and / or in contact with the solid sample 99.

[0198] By way of non-limiting example, the light-emitting means 17 are one or more LEDs, depending on the embodiment shown. The light-emitting means 17 are arranged and / or positioned and / or distributed in an annular manner around the tip 16 (if the sampler 1 includes a tip 17) or around the opening 22 and / or the sealing means 10.

[0199] By way of non-limiting examples, and with reference to [Fig.5], the MPCF 7s are arranged to, in addition, vacuum the conditioning chamber 31 and / or the receiving chamber 21.

[0200] According to the non-limiting embodiment, the MCPF 7 includes a vacuum pump 71. The vacuum pump 71 is connected, through a solenoid valve 72, to the conditioning chamber 31.

[0201] The conditioning block 3, in particular by means of the MPCF 7, and especially via the vacuum pump 71, is arranged to evacuate the receiving chamber 21 via the fluidic connection means 4.

[0202] Advantageously, the fluidic connection means 4 include a solenoid valve 4L. The solenoid valve 41 allows the receiving chamber 21 to be isolated and fluidically connected to the conditioning chamber 31. Thus, the vacuum created in the conditioning chamber 31 can be created in the receiving chamber 21 by opening the solenoid valve 4L. Equivalently, the calcination and / or combustion gases received in the receiving chamber 21 can be transferred, by opening the solenoid valve 41, into the conditioning chamber 31.

[0203] Advantageously, during the production of calcination and / or combustion gases, the solenoid valve 41 is closed. The solenoid valve 41 is opened, subsequent to the production of calcination and / or combustion gases, to transfer the calcination and / or combustion gases to the conditioning chamber 31.

[0204] According to the non-limiting embodiment, the sampler 1 includes a filter 133, disposed between the receiving chamber 21 and the conditioning chamber 31. Advantageously, the filter 133 is disposed downstream of the receiving chamber 21, with respect to the circulation of the calcination and / or combustion gases, and / or upstream of the conditioning chamber 31, with respect to the circulation of the calcination and / or combustion gases from the receiving chamber 21 to the conditioning chamber 31.

[0205] According to the embodiment, the filter 133 has a retention threshold of between 2 and 10 µm, with a retention threshold of 5 µm in the embodiment, allowing for coarse filtration of calcination and / or combustion gases. The filter 133 functions, among other things, to retain particles and / or dust originating from the solid sample 99. In particular, the filter 133 allows for the filtration of particles and / or dust, especially pumped or aspirated particles and / or dust and / or large particles, originating from the surface of the solid sample 99.

[0206] Advantageously, but not limitingly, the receiving block 2 may include an optical sensor 15. The optical sensor 15 is preferably disposed in the receiving chamber 21.

[0207] The optical sensor 15 is arranged to detect the light pulse produced during the initiation of calcination and / or combustion of the solid sample 99. Indeed, the initiation of the calcination and combustion reactions, and in particular the calcination reaction, produces a light flash (a brief and intense emission of light).

[0208] Advantageously the control unit 14 is arranged to control and / or verify and / or determine, by means of optical data measured by optical sensor 15, the production of calcination and / or combustion gases.

[0209] Advantageously, the MCPF 7 are arranged to inject an inert gas into the conditioning chamber 31 and / or into the receiving chamber 21.

[0210] According to the non-limiting embodiment, the MCPF 7 are arranged to inject an inert gas into the conditioning chamber 31. The MCPF 7 include a controlled injection means 73, 74, 75 of the inert gas into the conditioning chamber 31.

[0211] Elements 73 and 74 are solenoid valves. Element 75 is a mass flow control solenoid valve mounted to bypass solenoid valve 73. Solenoid valve 75 thus allows the controlled injection of inert gas into the conditioning chamber 31.

[0212] Preferably, the sampler 1 includes an inert gas storage tank 12.

[0213] The inert gas storage tank 12 is connected, fluidically, to the conditioning block 3, and, preferably, to the MCPF 7, in particular via fluidic connection means 78 and, preferably, to the conditioning chamber 31, in particular via the fluidic connection means 4 include a solenoid valve 41.

[0214] The conditioning block 3, and / or the MCPF 7, are arranged to transfer the conditioned gas into a transport bottle 8. The MCPF 7 further include a solenoid valve 77 mounted between the conditioning chamber 3 and the transport bottle 8.

[0215] The transfer of the conditioned gas to the transport bottle 8 is carried out by means of the MCPF 7 (in particular the solenoid valve 77). Once the conditioned gas is in the conditioning chamber 3, the solenoid valve 77 is opened so that the conditioned gas flows to the transport bottle 8. Preferably, prior to the extraction of the calcination and / or combustion gases, the transport bottle 8 is evacuated by means of the MCPF 7 (in particular the solenoid valves 72 and 77 and the vacuum pump 71). The transport bottle 8 is maintained under vacuum, by means of the MCPF 7 (in particular the solenoid valve 77), until the conditioned gases are transferred.

[0216] Thus, only lightweight elements are transported. In particular, gaseous samples are transported in lightweight tubes. Therefore, a large number of samples can be taken, and thus a large number of gaseous samples can be transported, with a reduced weight (without adding significant weight).

[0217] The conditioning block 3 and / or the MCPF 7 comprise a set of fluidic connection means 78 linking all or part of the different elements of the conditioning block 3 and / or the MCPF 7 together.

[0218] The sampler 1 advantageously includes the conditioning block 3, and / or the MCPF 7 include, a gas vent 79 out of the sampler 1. The vent 79 allows the gas to be vented during the operation of the vacuum pump 71.

[0219] The vacuum pump 71 also allows cleaning of all the fluidic elements of the sampler 1, in particular but not exclusively of the receiving chambers 2 and conditioning chambers 3, the MCPFs 7 and the connection means 4. By way of non-limiting example, the cleaning may consist of an injection of inert gas or air or ambient gas and then pumping the gas by vacuuming the element to be cleaned.

[0220] Advantageously, but not limitingly, the conditioning block 3, and / or the MCPF 7, may include a gas filter 132. Advantageously, The filter 132 is arranged upstream of the evacuation 79, and downstream of the conditioning chamber 31, and is arranged to filter the gases rejected or evacuated from the sampler 1. According to the embodiment, the filter 132 has a retention threshold of between 2 and 10 pm, a retention threshold of 5 pm according to the embodiment, allowing filtration of fine particles from the calcination and / or combustion gases and / or the purge gases evacuated.

[0221] Advantageously, the receiving block 2 further includes a pressure sensor 142 arranged to measure the gas pressure in the receiving chamber 21 and / or the conditioning block 3 further includes a pressure sensor 143 arranged to measure the gas pressure in the conditioning chamber 31.

[0222] The pressure sensor 142 is mounted on the receiving chamber 21. The pressure sensor 143 is mounted on the conditioning chamber 31. The pressure sensors 142 and 143 are arranged to measure the gas pressure before sampling (i.e. before irradiation of the solid sample 99 by the laser beam) and after sampling (and possibly during sampling, particularly for the receiving chamber 21).

[0223] The pressure value measured in the receiving chamber 21 and in the conditioning chamber 31 before sampling makes it possible to ensure that the desired or required pressure setpoint is reached or respected (it may be a desired vacuum value or a desired pressure value (whether in inert gas or in air or in ambient atmosphere).

[0224] The pressure value measured in the receiving chamber 21 after sampling, or the overpressure or pressure difference between the setpoint before sampling and the pressure value measured after sampling, makes it possible to check that a sufficient quantity of calcination and / or combustion gas has been generated.

[0225] Before transferring the calcination and / or combustion gases from the receiving chamber 21 to the conditioning chamber 31, the conditioning chamber 31 is advantageously, but not necessarily, placed or maintained under vacuum.

[0226] It is also possible, in particular when sampling is carried out with the receiving chamber 21 under vacuum, to supplement the calcination and / or combustion gases, in particular after their transfer into the conditioning chamber 31, with inert gas, i.e. to inject inert gas into the conditioning chamber 31.

[0227] The conditioning block 3 further includes a circulation pump 76 intended and / or arranged to circulate or put into circulation, in a closed loop, the calcination and / or combustion gases contained in the conditioning chamber 31.

[0228] According to the embodiment, the calcination and / or combustion gases are circulated from the conditioning chamber 31 through a filter 131 and then through a CO2 concentration sensor 141 to or towards the conditioning chamber 31. According to the embodiment, the filter 131 has a retention threshold of between 2 and 10 pm, a retention threshold of 5 pm according to the embodiment, allowing fine filtration of the calcination and / or combustion gas.

[0229] Thus, the closed-loop circulation in the fluidic loop comprising the circulation pump 76 and the filter 131 makes it possible to filter and homogenize the calcination and / or combustion gases.

[0230] Repeated circulation of calcination and / or combustion gases through the CO2 concentration sensor 141 allows the precise determination and / or measurement of the CO2 concentration contained in the calcination and / or combustion gases.

[0231] Once: - the calcination and / or combustion gases have circulated sufficiently in the closed loop 131, 76, 141, i.e., there is satisfactory filtration, and / or - that the stabilized and / or final and / or precise value of the quantity of CO2 measured and / or determined in the calcination and / or combustion gases is sufficient, i.e. greater than a threshold and / or predetermined value (which may for example depend on the type of rock analyzed 99), the calcination and / or combustion gases are considered as an analyzable gaseous sample or a conditioned gas and are transferred to the transport bottle 8.

[0232] Advantageously, the control unit 14 is arranged to vent / evacuate the calcination / combustion gases, via the vent 79, when: - during or after homogenization and / or filtration, the CO2 concentration, detected by the CO2 concentration sensor 141, did not conform to the threshold and / or predefined value, and / or - during or after the injection of inert gas into the conditioning chamber 31, the pressure value detected by the pressure sensor 143 does not conform to the threshold and / or predefined value, and / or - during or at the end of the sampling (the calcination / combustion of the solid sample 99) of the calcination / combustion gases, the pressure in calcination / combustion gas, measured by the pressure sensor 142, is not in accordance with the expected or predefined value.

[0233] According to an advantageous embodiment, the sampler 1 further comprises a carrying means 112. The carrying means 112 is arranged to be carried by the user. According to the non-limiting embodiment, the carrying means 112 is in the form of a backpack 112.

[0234] The sampler 1 includes fluidic and / or electrical connections linking and / or extending between the carrying means 112 and the gun 111 according to the embodiment.

[0235] According to the embodiment, the carrying means 112 comprises the inert gas reservoir 12, the control unit 14 and the laser source 5.

[0236] According to the non-limiting embodiment, the carrying means 112 further includes the vacuum pump 71.

[0237] Advantageously, the carrying means 112 comprises a frame 19 or a chassis on which are fixed and / or mounted the inert gas tank 12, the control unit 14, the laser source 5 and / or the vacuum pump 71.

[0238] Advantageously, the sampler 1 includes a power supply 18. The power supply can be a battery 18 or accumulator 18. The power supply 18 is arranged to supply, electrically, all or part of the elements suitable for or requiring to be electrically supplied.

[0239] By way of non-limiting example, the power supply may be arranged to and / or dedicated to supplying, electrically: - control unit 14, - pumps 71, 76, - pneumatic valves 41, 72, 73, 74, 75, 77, - pressure sensors 142, 143, - the CO2 concentration sensor 141, - the laser source 5, - the optical head 6 and / or the rotation device 64 and / or the motor 633, - the optical sensor 15, and / or - means of emitting light 17.

[0240] Incidentally, the power supply 18 can be connected to means of energy production, for example a solar panel or a fuel cell.

[0241] According to the preferred embodiment, the solid sample 99 is a rock 99 containing carbonates. Unlike prior art methods, the rocks are not treated, prepared, or subjected to any surface treatment prior to the preparation of the gaseous sample.

[0242] Irradiating rock 99 with the laser beam mainly causes the calcination of rock 99, which will release mainly carbon dioxide (CO2), which will be collected in the receiving chamber 2.

[0243] Unlike combustion, the calcination reaction is a self-sustaining reaction that, once initiated, does not require the presence of oxygen. Thus, sampling can be carried out when the receiving chamber 2 is placed under vacuum or an inert atmosphere prior to irradiation of the solid sample 99 by the laser beam.

[0244] However, the invention does not exclude the possibility that, when at least part of the combustion of the solid sample 99 is sought, the possibility of using ambient air or ambient atmospheric gas or a gas (stored in a storage tank of the sampler 1) enriched in oxygen.

[0245] The isotopic analysis of carbon and / or oxygen will be representative of the type of rock analyzed. Another advantage of preparing the calcination reaction, through the use of the laser source and / or laser beam under the conditions of the invention, is to obtain a reaction efficiency of 100%. This makes it possible to recover the maximum amount of carbon dioxide without losing information about the analyzed solid sample.

[0246] Indeed, state-of-the-art ablation lasers do not have 100% isotopic yield. Ablation lasers also induce matrix effects that make the preparation of the gaseous sample dependent on the type of rock being analyzed. Another advantage of the fact that the gaseous sample preparation is based almost entirely on the calcination reaction is that the preparation is not matrix-dependent and the production of irradiated gas is not matrix-dependent.

[0247] With reference to [Fig.8], a photograph of the surface of a solid sample 99, of a carbonate rock 99 according to the embodiment, obtained after irradiation by the laser beam of the sampler 1 according to the invention, is illustrated.

[0248] The area irradiated 991 by the laser beam has the shape of a circle 991 or an arc of a circle 991.

[0249] Thus, the rotational motion described by the laser beam axis, and / or the precessional motion described by the laser beam axis, allows the irradiated surface area and / or volume of the irradiated solid sample 99 to be significantly greater than the surface area and / or volume irradiated by a fixed or stationary laser beam. The quantity of calcination and / or combustion gas produced is therefore considerably greater than the quantity of gas produced by irradiating a solid sample with a fixed laser beam. The circle 991 described by the laser beam on the solid sample 99 in [Fig. 8] has a diameter of 4 mm according to the embodiment.

[0250] According to the non-limiting embodiment, the optical head 6 is arranged to impart successive rotations to the laser beam. Thus, a set of points or spots are formed along the visible arc of a circle 991 on [Fig. 8]. Each point or spot corresponds to the position of the laser beam during successive productions of the calcination / combustion gases. According to this embodiment, the actual production of calcination / combustion gas can be controlled, determined, or verified for each successive position, for example, by the control unit 14, from the optical data measured by the optical sensor 15 and / or from the pressure measurement data from the pressure sensor 142.

[0251] According to the invention, a method for producing a gaseous sample from a solid sample 99, referred to as the method, is also proposed.

[0252] The process is implemented using a portable gas sample production device.

[0253] The sampler 1 according to the invention is suitable, preferably moreover, is particularly adapted, more preferably is designed, and particularly advantageously is specially designed, for implementing the process. Also, advantageously, the process is implemented by the sampler 1 according to the invention.

[0254] To this end, the process includes the steps of: - emit a laser beam, from the laser source 5, scanning, at least in part, the aperture 22, - to generate calcination and / or combustion of a portion of the solid sample 99, by said laser beam, - to receive calcination / combustion gases, through opening 22, into receiving chamber 21, - transfer the calcination / combustion gases from the receiving chamber 21 into the conditioning chamber 31, - filter and homogenize the calcination / combustion gases in the conditioning chamber 31.

[0255] Advantageously, it is also envisaged that the process may also include all other secondary functions or improvements of the sampler 1. In particular, the process may also include the steps associated with the secondary functions or improvements of the elements of the sampler 1 and / or the secondary steps or steps relating to the improvements implemented by the sampler 1 according to the invention.

[0256] Advantageously, the control unit 14 is arranged and / or configured and / or programmed to implement, at least in part, the method according to the invention. Conversely, the method according to the invention comprises, in whole or in part, the features and functions implemented by the control unit 14.

[0257] Each aspect or improvement of the invention can be implemented individually.

[0258] Each aspect or improvement can be combined with one, several or all of the other aspects or improvements of the invention.

[0259] Of course, the invention is not limited to the examples just described and many modifications can be made to these examples without departing from the scope of the invention.

[0260] Thus, in combinable variants of the embodiments described above: - the fluid connection means 4, 78 can be tubes, conduit(s), pipes, flexible or rigid, and / or - the term "under vacuum", specifically "vacuum sealing", in this application means: a predefined pressure value, for example, a value less than or equal to 20 mbar, preferably less than or equal to 10 mbar, and / or - the inert gas can be a noble gas, in particular Argon, or nitrogen or a mixture of these gases.

[0261] In particular, all the variants and embodiments described are combinable with each other if there is no technical obstacle to this combination.

Claims

Demands

1. A portable device for producing a gaseous sample from a solid sample (1), referred to as the sampler (1), said sampler comprising: - a sampling block (2) and a conditioning block (3), - fluidic connection means (4) arranged to fluidly connect the sampling block and the conditioning block, - a laser source (5) arranged to emit a laser beam capable of generating calcination and / or combustion of a part of the solid sample (99); said sampling block comprising: - a chamber (21), referred to as the receiving chamber (21), intended to receive calcination / combustion gases from the solid sample;said receiving chamber includes an opening (22) formed in a wall (23) of said receiving chamber intended to be brought opposite the solid sample, - an optical head (6), coupled to said laser source, arranged to: • direct said laser beam through said opening, and • vary an axis of the laser beam so that the laser beam sweeps, at least in part, said opening, said conditioning block includes: - a chamber (31), called conditioning chamber (31), intended to receive the calcination / combustion gases from the receiving chamber, - pneumatic and fluidic connection means (7) arranged to filter and homogenize the calcination / combustion gases in the conditioning chamber.;

2. Sampler (1) according to claim 1, wherein the laser source (5) is arranged so that the laser beam has an irradiance of less than 5 MW / cm2 at a given impact zone on a surface of the solid sample (99).

3. Sample (1) according to claim 1 or 2, wherein: - the receiving chamber (21) further comprises an optical window (24) provided in a wall of the receiving chamber opposite the wall (23) of said receiving chamber intended to be brought opposite the solid sample (99), - the optical head (6) is arranged opposite said optical window.

4. Sample (1) according to any one of the preceding claims, comprising laser beam shaping means (62) arranged to shape the laser beam emitted by the laser source (5).

5. Sample (1) according to any one of the preceding claims wherein the pneumatic and fluidic connection means (7) are arranged to, furthermore: - evacuate the conditioning chamber (31) and / or the receiving chamber (2), and / or - transfer the conditioned gas into a transport bottle (8).

6. Sample (1) according to any one of the preceding claims, wherein the optical head (6) is arranged to impart: - a rotational movement to the axis of the laser beam, and / or - a precessional movement to the axis of the laser beam.

7. Sample (1) according to any one of the preceding claims, wherein the optical head (6) is arranged to: - rotate the laser beam axis around an axis of revolution of the aperture (22), and / or - precess the laser beam axis relative to an axis of revolution of the aperture.

8. Sample (1) according to claim 6 or 7, wherein the optical head (6) is arranged so that the axis of the laser beam is offset and parallel to the axis of revolution of the aperture (22).

9. Sample (1) according to any one of claims 6 or 7, wherein the optical head (6) is arranged so that the axis of the laser beam forms a non-zero angle with the axis of revolution of the aperture (22).

10. Sampler (1) according to any one of the preceding claims, wherein the receiving chamber (21) comprises, on the outside of the wall (23) of the receiving chamber intended to be carried opposite the solid sample (99), a sealing means (10) extending around the opening (22) and arranged to ensure sealing between said solid sample and said opening.

11. Sampler (1) according to any one of the preceding claims, wherein the pneumatic and fluidic connection means (7) are arranged to inject an inert gas into the conditioning chamber (31) and / or into the receiving chamber (21).

12. Sampler (1) according to the preceding claim, wherein: - the conditioning chamber (31) comprises at least one pressure sensor (143) arranged to measure the pressure in the conditioning chamber, and / or - the receiving chamber (21) comprises: • at least one pressure sensor (142) arranged to measure the pressure in the receiving chamber, and / or • at least one optical sensor (15) arranged to detect a light pulse produced during the initiation of calcination and / or combustion of the solid sample (99).

13. Sampler (1) according to any one of the preceding claims, wherein the conditioning block (2) includes a CO2 measuring sensor (141), arranged to measure, in the conditioning chamber (31), the amount of CO2 contained in the calcination / combustion gases.

14. Sampler (1) according to any one of the preceding claims, comprising: - a gun (111) operable and manipulable by one hand, the sampling block (2) and the conditioning block (3) being included in said gun operable and manipulable by one hand,

15. - one or more carrying devices (112), arranged to be carried by a user, said carrying device comprising: • a storage tank (12) for the inert gas, and / or • a power supply, and / or • a control unit (14). A method for producing a gaseous sample, using a portable gaseous sample production device, called a sampler, from a solid sample, comprising the steps of: - emit a laser beam, from a laser source of said sampler, scanning, at least in part, an aperture of said sampler, - to generate calcination and / or combustion of a portion of the solid sample, by said laser beam, - to receive calcination / combustion gases, through the opening, into a receiving chamber of said sampler, - transfer the calcination / combustion gases from the receiving chamber into a conditioning chamber of said sampler, - filter and homogenize the calcination / combustion gases in the conditioning chamber.

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