System for supplying oxygen to a patient with an electrochemical separation module with a ceramic membrane

Description

[0001] The present invention relates to an installation for supplying respiratory gas, such as pure or almost pure oxygen, to an individual, i.e. a human being, typically a patient in a hypoxemic state, including an electrochemical separation module with a ceramic membrane. Such an installation can be used to treat in particular a person in a hypoxemic state infected by a coronavirus, such as Covid-19 or the like, whether an adult, in particular an elderly person, an adolescent or a child.

[0002] The administration of gaseous oxygen (O 2 ) is used to correct a hypoxemic situation, i.e. when the saturation of oxyhemoglobin in the blood or "oxygen saturation" becomes or is lower than a normal value, i.e. outside the 95-100% range, in particular lower than 90%, in a human individual, i.e. a patient in a population of patients such as newborns, children or adults, suffering from a respiratory pathology, for example Chronic Obstructive Pulmonary Disease (COPD) or Acute Respiratory Distress Syndrome (ARDS), in particular in the context of the pandemic linked to the Covid-19 coronavirus.

[0003] In the hospital, oxygen comes from one (or more) large-capacity tanks (i.e. storage of several thousand liters), in particular containing oxygen in liquid form (LOX), which is first vaporized, then conveyed and finally delivered by one or more wall-mounted gas distribution outlets arranged in the rooms of the hospital or similar, in particular bedrooms, treatment rooms, etc. The outlets are fluidically connected to the hospital's oxygen pipeline network supplied by the large-capacity storage. Such an installation normally ensures a continuous supply of gaseous O 2 to patients. The large-capacity tank must be regularly replenished with LOX, typically by tanker truck.

[0004] Depending on the criticality of the patient's condition, oxygen flow rates can be high, typically up to 15 L / min or more. The desired oxygen flow rate is generally set by means of a flow meter fluidly connected to the wall outlet supplying the oxygen, then delivered to the patient in need, via a gas delivery line fluidly connected to the flow meter outlet and feeding a respiratory interface, such as a nasal-oral (i.e., facial) respiratory mask. This makes it possible to obtain a fraction of inspired oxygen (FiO 2 ) by the patient that is greater than 90% and, in general, close to 100%.

[0005] However, the COVID-19 coronavirus pandemic has increased the number of hypoxemic patients requiring treatment with high concentrations of O2 to restore their normal oxygen saturation, which has caused numerous oxygen supply problems in developed countries and even made the task almost impossible in less developed countries, where access to O2 is more difficult, whether for production, logistical or other reasons, leading to an unprecedented health crisis for the population, particularly for patients who have been deprived of or limited in oxygen.

[0006] FR2106772 proposes to reduce oxygen consumption by removing CO2 from exhaled gases using adsorbent cartridges. The purified oxygen-rich gas can then be reinhaled by the patient. The adsorbent is periodically regenerated by a flow of ambient air. However, this type of system may prove insufficient when large quantities of oxygen are required while available oxygen sources are limited or subject to constraints, particularly space constraints, such as in retirement homes and / or remote or difficult-to-access rural areas, or in the context of medical evacuation of several patients by plane, train or other means. In addition, regeneration by ambient air is incomplete, which impacts the adsorption capacity, which reduces over time and requires frequent maintenance.

[0007] Alternatively, it is known, in particular from US-A-4,859,217, EP-A-0785020 and EP-A-1157731, to be able to use a PSA (Pressure Swing Adsorption) type pressure swing adsorption installation to separate, directly "on site", the ambient air and produce gaseous O 2 at approximately 90% purity. However, a PSA installation of this type cannot deliver flow rates greater than 10 L / min and is also heavy and bulky. It is also not possible to substitute a PSA installation for the O 2 source used in FR2106772 because PSAs generate a mixture of gases rich in nitrogen and argon that cannot be purified and thus accumulate to the detriment of the oxygen level.

[0008] WO98 / 22173 is also known, which describes an anesthesia installation comprising a gas source for supplying an anesthetic gas containing oxygen, a main line for conveying the gas to a respiratory interface, a gas recovery line for bringing the gases exhaled by the patient to a gas purification system and a gas recycling line.

[0009] US 2019 / 329076 A1 is also known, which describes an absorber regeneration system.

[0010] Furthermore, US2006 / 062707 proposes a ceramic membrane oxygen generation device for producing oxygen from ambient air.

[0011] In view of this, there is a need to propose an improved O2 supply plant that allows efficient recycling of exhaled gases with continuous CO2 purification, improved regeneration of adsorbers or adsorption cartridges and simultaneous in-situ production of oxygen from ambient air, while limiting power consumption and being of simple design.

[0012] According to the invention, there is provided an installation for supplying respiratory gas to a user, i.e. a patient, in particular oxygen, comprising: a gas source for supplying a respiratory gas containing oxygen, a main gas delivery line fluidly connecting the gas source to a respiratory interface, configured to administer the respiratory gas containing oxygen to the user, during each inspiratory phase of said user, a gas recovery line configured to recover and convey at least a portion of the CO 2 / O 2 gas mixture exhaled by the user and found in the respiratory interface, during each expiratory phase of the user, said gas recovery line fluidly connecting the respiratory interface to a gas purification system comprising adsorbers arranged in parallel each containing at least one adsorbent, and a gas recycling line fluidly connecting the gas purification system to the main gas delivery line.

[0013] According to the invention, the gas source of the respiratory gas supply installation comprises an oxygen generation unit, said oxygen generation unit comprising: at least one electrochemical separation module, a first gas line for supplying said at least one electrochemical separation module with air, gas heating means arranged on the first internal gas line, upstream of said at least one electrochemical separation module and a second gas line fluidly connecting said at least one electrochemical separation module to the gas purification system, for conveying a waste gas stream to the gas purification system to regenerate said at least one adsorbent contained in at least one of said adsorbers.

[0014] Indeed, using waste gas to regenerate the adsorbent(s) contained in the adsorbers is particularly advantageous because it is at a high temperature, for example around 300°C, which allows the regeneration of the adsorbent(s).

[0015] Depending on the embodiment considered, the gas supply installation according to the invention may comprise one or more of the following characteristics: the gas source, i.e. the oxygen generation unit, is configured to provide a respiratory gas containing at least 95% vol. of oxygen, in particular pure or almost pure oxygen, i.e. having a purity of at least approximately 98% vol., preferably at least approximately 99% vol., more preferably at least 99.5% vol. the respiratory interface is configured to administer a respiratory gas to the user containing at least 98% vol. of oxygen, typically almost pure oxygen, i.e. having a purity of at least approximately 99% vol., during each inspiratory phase of the user, the main gas delivery line is configured to deliver the breathing gas containing at least 95% vol. of oxygen from the gas source to the breathing interface. the gas recovery line is configured to recover and deliver at least a portion of the CO 2 / O 2 gas mixture exhaled by the user, i.e. found in the breathing interface, during each expiratory phase of the user, each adsorber of the gas purification system is configured to operate according to adsorption / regeneration cycles. the gas purification system is configured to be supplied with exhaled CO 2 / O 2 gas mixture by the gas recovery line. the gas purification system is further configured to remove at least a portion of the CO 2 contained in the exhaled CO 2 / O 2 gas mixture and obtain a purified gas (i.e. recycled gas) containing mainly O 2 , typically having a purity of at least approximately 95% vol.the gas recycling line fluidly connecting the gas purification system to the main gas delivery line is configured to convey at least a portion of the purified gas containing predominantly O 2 from the gas purification system and reinject it into the main gas delivery line, preferably via a buffer tank. the gas purification system is or comprises a gas purification device. the gas purification system comprises at least three adsorbers (also called cartridges) arranged in parallel, typically 3 to 5 adsorbers, preferably 3 adsorbers. the main gas delivery line comprises a buffer tank and the gas recycling line is fluidly connected to the buffer tank. the gas recycling line is fluidly connected to the buffer tank to supply it with purified gas (i.e.recycled gas) from the gas purification system, preferably a recycled gas containing at least 95% vol. of oxygen. the buffer tank is arranged on the main gas supply line so that the gas carried by the main gas supply line successively enters and exits the buffer tank. the main gas supply line carries high purity oxygen, i.e. having a purity of at least 99% vol., preferably at least 99.5% vol. the gas purification system is fluidically connected to the first gas line of the oxygen generation unit to supply air to said first gas line. the gas purification system is fluidically connected to the first gas line of the oxygen generation unit via a first interconnecting conduit. the gas purification system comprises an air circuit for supplying air supplied to the first gas line of the oxygen generation unit.the air circuit conveys air within the gas purification system between an air intake duct and an air extraction duct. the air circuit of the gas purification system comprises air passages or ducts and at least one adsorber, the air circuit of the gas purification system further comprises at least one control valve, in particular one or more rotary valves. at least one adsorber is arranged on the air circuit between the air intake duct and the air extraction duct. the air intake duct comprises an air inlet port and the air extraction duct comprises an air outlet port. at least one control valve is arranged on the air circuit between the air intake duct and at least one adsorber. at least one control valve is arranged on the air circuit between at least one adsorber and the air extraction duct.The gas purification system further comprises a regeneration circuit for conveying the waste gas supplied by the oxygen generation unit. The regeneration circuit conveys the waste gas within the gas purification system between a regeneration conduit and an exhaust conduit. The regeneration conduit is fluidically connected to the second interconnecting conduit so as to be supplied with waste gas. The exhaust conduit is fluidically connected to the atmosphere in order to allow the regeneration gas flow to be evacuated therein, after passing through at least one adsorber. The regeneration circuit of the gas purification system comprises air passages or conduits and at least one adsorber, preferably the adsorbers. The regeneration circuit further comprises at least one control valve, in particular one or more rotary valves. The gas purification system further comprises a gas recycling circuit.the gas recycling circuit conveys the flow of exhaled gas to be purified (i.e. O 2 / CO 2 mixture) and the flow of purified gas (i.e. O 2 ) within the gas purification system between a gas inlet conduit and an outlet conduit. the inlet conduit is fluidically connected to the gas recovery line so as to recover the flow of exhaled gas to be purified (i.e. O 2 / CO 2 mixture) supplied by said gas recovery line. the outlet conduit is fluidically connected to the gas recycling line to supply it with oxygen, i.e. recycled gas, produced by the exhaled gas purification unit. the gas recycling circuit comprises air passages or conduits and at least one adsorber, preferably the adsorbers. the recycling circuit further comprises at least one control valve, in particular one or more rotary valves.said at least one electrochemical separation module of the oxygen generation unit comprises one or more ceramic membranes. the ceramic membrane(s) are doped with one or more electrolytes. the first gas line of the oxygen generation unit comprises gas suction means, such as a fan, a blower, a suction pump or the like. the gas heating means comprise or are an electric heating device. the gas heating means are configured to preheat the air flow to a temperature above 400°C, preferably at least 500°C, more preferably at least 600°C. the gas heating means are arranged between the gas suction means and said at least one electrochemical separation module. heat exchange means are arranged on the first gas line and on the second gas line. the heat exchange means comprise a heat exchanger (ieof calories), preferably a countercurrent heat exchanger. the heat exchange means are arranged between the gas suction means and the gas heating means. the second gas line of the oxygen generation unit is arranged in parallel with the first gas line within said heat exchange means so as to carry out a heat exchange between the air flow circulating in the first gas line and the waste gas circulating in the second gas line, preferably a countercurrent heat exchange. the heat exchange means are configured to ensure a transfer of calories from the waste gas carried by the second gas line to the air carried by the first gas line so as to heat the air and cool the waste gas. the second gas line of the oxygen generation unit conveys a waste gas having an oxygen concentration of less than 21% vol., preferably less than or equal to typically less than or equal to 19% vol. the second gas line of the oxygen generation unit conveys a waste gas having a temperature of at least 250°C, typically at least approximately 300°C, preferably after passing through the heat exchange means (i.e. at the outlet). the gas purification system comprises second control means configured to control the operation of the gas purification system, in particular the control valves, i.e. the rotary valves. a second interconnection conduit fluidly connects the second gas line of the O 2 generation unit to the gas purification system. the second interconnection conduit conveys the waste gas between the O 2 generation unit and the gas purification system. said at least one electrochemical separation module of the oxygen generation unit comprises one or more ceramic membranes.the ceramic membranes are doped with one or more electrolytes. the electrolyte(s) comprise or are for example cerium-based compounds. the (or each) ceramic membrane is configured to allow the O 2 molecules contained in the gas, i.e. air, to pass through it while retaining the molecules of other gaseous compounds or species, in particular those of nitrogen, CO 2 , argon etc.... the oxygen generation unit provides oxygen at a concentration of at least 99% by volume, preferably at least 99.5% by volume, advantageously between 99.5% and 100%. the or each O 2 separation module comprises an air inlet through which the air carried by the first gas line enters the or each O 2 separation module, before its separation by the (or the) ceramic membrane(s) arranged in the or each O 2 separation module.the or each O 2 separation module comprises a first outlet supplying the first outlet conduit with a flow of high-purity oxygen produced by the ceramic membrane(s). the or each O 2 separation module comprises a second outlet supplying the second gas line with waste gas formed from gaseous compounds that have not passed through, i.e. have been retained, by the ceramic membrane(s), typically nitrogen, CO 2 , argon, etc. the first control means comprise a first electronic control card and a first microprocessor control unit(s), typically one or more microcontrollers. the O 2 generation unit comprises first control means configured to control each O 2 separation module. the first control means are further configured to control the heating means and / or the gas suction means.the first control means are configured to electrically power the ceramic membrane(s) of the or each O 2 separation module the first control means are electrically powered by electrical power supply means, such as the mains (110 / 220 V) and / or a rechargeable battery or the like. the respiratory interface is a respiratory mask or the like, in particular a face mask, ie oronasal, covering the nose and mouth of the user. the respiratory interface comprises an oxygen inlet port and an exhaled gas outlet port, ie O 2 / CO 2 mixture. the respiratory interface is a respiratory mask comprising an oxygen inlet port or port for supplying the oxygen-rich gas and an exhaled gas outlet port or port for discharging the CO 2 / O 2 gas mixture exhaled by the user.the breathing mask comprises a flexible cushion coming into contact with and ensuring a fluid seal with the user's face. the breathing mask comprises a mask body, for example made of rigid polymer, forming a shell delimiting an enclosure for the gas. the flexible cushion is mechanically coupled to the mask body, preferably in a detachable manner. the flexible cushion comprises a central passage within which the nose and mouth of the user are housed, when wearing the face mask. the user breathes the gas contained in the enclosure, that is to say inhales and exhales the gas in the enclosure of the mask body. the oxygen inlet port and the exhaled gas outlet port are arranged in the mask body.the main gas supply line and / or the gas recovery line and / or the gas recycling line are or comprise one or more gas lines, preferably flexible, i.e. flexible hoses, for example made of polymer. the main gas supply line and / or the gas recovery line are connected to the mask body so as to be in fluid communication with the oxygen inlet port and the exhaled gas outlet port. the main gas supply line is fluidly connected to the oxygen inlet port and the gas recovery line is fluidly connected to the exhaled gas outlet port of the respiratory interface. the main gas supply line is fluidly connected to the oxygen inlet port of the respiratory interface so as to introduce respiratory gas into the respiratory interface.the gas recovery line is fluidically connected to the exhaled gas outlet of the respiratory interface so as to extract a gas exhaled by the patient from the respiratory interface, typically a gas containing oxygen and CO 2 , and usually water vapor. the gas recycling line is fluidically connected to the buffer tank to supply it with purified gas, i.e. recycled gas. the oxygen-rich purified gas conveyed by the gas recycling line contains a proportion (i.e. content) of oxygen less than or equal to the gas coming from the gas source, i.e. (near)pure oxygen, and conveyed by the main gas delivery line. the buffer tank comprises a flexible balloon, bellows or the like. the buffer tank comprises an exhaust valve for venting any excess gas, i.e. O 2 , to the atmosphere when the buffer tank is full of gas, i.e. oxygen.the buffer tank is sized to contain from 0.5 to 5 liters of gas (in the uncompressed state). the buffer tank is configured to allow a gas mixture to be produced therein from oxygen-rich breathing gas (preferably >99% O 2 ) coming from the main gas supply line, such as pure oxygen (i.e. approx. 100%), and purified gas, i.e. recycled gas containing at least 99% oxygen, coming from the gas recycling line. the buffer tank is configured to supply the main gas supply line with oxygen resulting from the gas mixing carried out in the buffer tank. the gas purification system comprises at least one adsorbent having a higher selectivity for CO 2 than for O 2 so as to adsorb at least a portion of the CO 2 contained in the exhaled CO 2 / O 2 gas mixture.the gas purification system comprises at least one zeolitic adsorbent, i.e. chosen from exchanged or non-exchanged zeolites, and / or at least one adsorbent chosen from silicates. the gas purification system comprises several adsorbers each containing at least one zeolitic or silicate adsorbent, or mixtures thereof. the gas purification system comprises at least one adsorbent for removing CO 2 and water vapor (H 2 O), i.e. the CO 2 and water vapor are removed on the same bed of adsorbent, for example a single zeolite bed, or on successive beds of different absorbents, for example a silicate bed and a zeolite bed. the adsorbers are arranged in parallel and operate alternately. the adsorbers are or have a cartridge shape. The gas purification system comprises three adsorbers comprising a first adsorber or cartridge, a second adsorber or cartridge, and a third adsorber or cartridge.Each adsorber is configured to operate according to PSA (Pressure Swing Adsorption) adsorption / regeneration cycles, i.e., pressure-swing adsorption. During operation of the gas purification system, one of the adsorbers is in the adsorption phase and one or both of the other adsorbers are in the regeneration phase. Alternatively, during operation of the gas purification system, one adsorber is in the adsorption phase, while two adsorbers are in the regeneration phase, i.e., there are always more adsorbers in the regeneration phase than in the adsorption phase. In the adsorption (i.e., production) phase, the adsorbent adsorbs, i.e., traps / retains, at least some of the CO2 and water vapor (H2O) contained in the exhaled CO2 / O2 gas mixture. in the regeneration phase (i.e. desorption phase), at least part of the CO2 and possibly the water vapor having been adsorbed by the adsorbent is desorbed, i.e.released. in the regeneration phase, the regeneration of the adsorbent by the waste gas flow coming from the O 2 generation unit is carried out countercurrently. the gas purification system further comprises one or more control valves, also called distribution valves, arranged, on the gas path, upstream and / or downstream of the adsorbers to control the gas inlets and outlets of said adsorbers, for example rotary valves or other valves. the control valve(s) are controlled by the second control means of the gas purification system. the control valve(s) are rotary valves. the installation further comprises electrical supply means supplying the components of the installation requiring electrical current to operate, in particular the control means. the gas purification system is arranged in a rigid housing.the recycling circuit comprises at least one flow sensor, in particular a mass flow sensor. at least one flow sensor is arranged in the inlet duct of the recycling circuit. at least one flow sensor cooperates with the second control means of the gas purification system, in particular by providing it with flow measurements.

[0016] According to another aspect, the invention also relates to a method for regenerating one or more adsorbers of the gas purification system of a respiratory gas supply installation according to the invention, in particular the respiratory gas supply installation described above, in which: a) recovers at least a portion of the waste gas generated by at least one electrochemical separation module of the O2 generation unit; b) conveys the waste gas to the gas purification system; and c) brings the waste gas into contact with at least one adsorbent contained in at least one adsorber of the purification system to regenerate said at least one adsorber.

[0017] Depending on the embodiment considered, the regeneration method of the invention may comprise one or more of the following characteristics: the waste gas comprises less than 21% vol. of oxygen. in step c), the waste gas is at a temperature of at least 250°C, preferably at least 300°C, the waste gas is cooled by heat exchange with an air flow before step c). the waste gas is obtained by air separation in said at least one electrochemical separation module with production, in addition, of an oxygen flow. said at least one adsorbent is regenerated countercurrently. the waste gas flow passes through said at least one adsorbent to regenerate it. after passing through said at least one adsorbent, the waste gas flow is discharged to the atmosphere. It comprises the compounds desorbed from the adsorbent, in particular CO 2 and water vapor.

[0018] The invention will now be better understood thanks to the following detailed description, given for illustrative but non-limiting purposes, with reference to the appended figures among which: Fig. 1 schematizes an embodiment of an O2 supply installation according to the present invention. Fig. 2 schematizes an embodiment of the O2 generation unit of the installation of Fig. 1 . Fig. 3 schematizes an embodiment of the architecture of the expired gas purification unit of the installation of Fig. 1 . Fig. 4 represents the subassemblies of a rotary valve used to distribute gases in the exhaled gas purification unit of Fig. 3 . Fig. 5 represents the rotary valve used to distribute gases in the exhaled gas purification unit of Fig. 3 .

[0019] Fig. 1 schematizes an embodiment of an installation 50 for supplying an O 2 -rich gas mixture according to the present invention comprising an oxygen generation unit 30 as a gas source 3 supplying an oxygen-rich respiratory gas (O 2 content >99% by vol) to a main gas delivery line 23, also called a patient circuit, for conveying the flow of respiratory gas from the gas source 3 to a respiratory interface 21, such as a mask or the like, making it possible to administer the gas to a user P, i.e. a patient, during his inspiratory phases, i.e. when he inhales gas.

[0020] The operation and architecture of the oxygen generation unit 30 are detailed below.

[0021] The installation 50 also comprises an exhaled gas recovery line 10 fluidly connected to the respiratory interface 21 which makes it possible to recover and convey all or part of the CO2 / O2 gas mixture exhaled by the patient P, during his expiratory phases, which ends up in the respiratory interface 21, when the patient P exhales.

[0022] The gas recovery line 10 supplies an exhaled CO 2 / O 2 gas mixture to a gas purification system 1 used to eliminate the majority and, preferably (almost) all, of the CO 2 contained in the exhaled CO 2 / O 2 gas mixture and thus obtain a purified gas containing essentially oxygen, i.e. O 2 .

[0023] A gas recycling line 11 fluidly connected to the gas purification system 1 makes it possible to recover the oxygen supplied by the gas purification system 1 and then brings it to the main gas delivery line 23, via a buffer tank 24. The buffer tank 24 is therefore arranged on the main gas delivery line 23, in particular supplied by the latter, and furthermore supplied by the gas recycling line 11.

[0024] The main gas delivery line 23, also called the patient circuit, comprises a flexible pipe or the like, and is fluidically connected, via its downstream end, to the inlet orifice or port 22 of the respiratory interface 21, such as a face mask, so as to supply the patient P with O2 coming from the buffer tank 24.

[0025] The buffer tank 24 serves as a reserve of breathing gas, i.e. oxygen. It is in fluid communication not only with the O 2 generation unit 30 but also with the gas purification system 1. In other words, the buffer tank 24 is supplied with a first flow of (quasi-)pure oxygen (content equal to approx. 100% O 2 ) conveyed by the main gas supply line 23 coming from the O 2 generation unit 30 and by a second flow of recycled purified oxygen coming from the recycling line 11 supplied by the gas purification system 1, preferably purified oxygen having a purity of the order of 99% or more, as explained below. The two oxygen flows therefore mix in the buffer tank 24.

[0026] When patient P breathes, the buffer tank 24 which is filled with oxygen, satisfies the instantaneous demand of patient P by providing him with at least part of the oxygen it contains, i.e. (quasi-)pure oxygen (with possible unavoidable impurities).

[0027] Furthermore, the gas exhaled, i.e. a CO2 / O2 gas mixture, by the patient P leaves the respiratory interface 21 through an outlet port or orifice 25 provided in the respiratory interface 21, before being recovered and conveyed by the gas recovery line 10 forming an expiratory circuit, such as a flexible gas conduit or pipe, fluidically connected to the outlet port 25 of the respiratory interface 21.

[0028] The gas recovery line 10 therefore makes it possible to recover and convey (at least part of) the CO2 / O2 gas mixture exhaled by the user found in the respiratory interface 21, during the expiratory phases of the user P, to the gas purification system 1 where it is purified, as explained above.

[0029] In all cases, the CO 2 / O 2 gas mixture exhaled by the patient P still contains a high proportion of unmetabolized O 2, typically at least 90 to 95% residual O 2, while its carbon dioxide CO 2 content from cellular respiration and pulmonary exchanges is low, typically of the order of 5% vol. The exhaled gas may also contain other unavoidable gaseous compounds or impurities, in particular water vapor (H 2 O), or even nitrogen and / or argon in negligible quantities which may result, for example, from sealing defects at the respiratory interface 21, in particular on the contours of the mask.

[0030] As already stated, the CO 2 / O 2 mixture gas flow is conveyed by the gas recovery line 10 to the expired gas purification unit 1 within which the CO 2 and preferably the water vapor are purified / eliminated, in particular adsorbed, i.e. captured, by one (or more) bed(s) of adsorbents 130-132 of the purification unit 1, as explained below and illustrated in Fig. 3 .

[0031] It should be noted that, in the context of the present invention, the terminology "the exhaled gas" or "the exhaled gases" (i.e. singular or plural) is used interchangeably to designate the gas mixture released by the patient's lungs, i.e. exhaled, which mainly contains O 2 (e.g. >90% vol.), CO 2 (e.g. of the order of approximately 5% vol.) and generally water vapor, or even other possible unavoidable impurities.

[0032] The purified gas, i.e. (quasi) pure oxygen produced by the purification unit 1, essentially contains oxygen and small, even negligible, quantities of CO2 and possibly water vapor (i.e. humidity) which have not been eliminated. In all cases, the purified gas, i.e. oxygen, has, after purification, an oxygen content much higher than that of the exhaled gas (i.e. O2 / CO2 mixture), typically the purified oxygen has a purity of at least 99% vol. approximately.

[0033] Indeed, the gas purification system 1, which is supplied with exhaled CO 2 / O 2 gas mixture (i.e. O 2 content < 95% approx.) by the gas recovery line 10, makes it possible to eliminate the majority of the CO 2 and preferably the water vapor contained in the exhaled CO 2 / O 2 gas mixture and to obtain a purified gas formed essentially of (quasi-)pure oxygen (e.g. O 2 content > 99.90% approx., or even >99.95% vol.).

[0034] Downstream of the gas purification system 1, a gas recycling line 11 fluidically connected to the gas purification system 1 and also to the main gas delivery line 23, via the buffer tank 24, makes it possible to collect and deliver the purified gas containing essentially oxygen (i.e. O 2 content > 99.9% approx.) produced by the gas purification system 1 and to reinject it into the main gas delivery line 23, i.e. into the oxygen flow coming from the O 2 generation unit 3. The oxygen coming from the gas purification system 1 therefore mixes with the oxygen flow coming from the oxygen generation unit 30, as explained below.

[0035] The amount of residual CO2 and water vapor compounds in the purified gas from the gas purification system 1 are negligible, typically <0.1% vol., i.e. the purified gas consists essentially of near-pure O2.

[0036] The purified gas, i.e. oxygen, is therefore conveyed by the gas recycling line 11 to the tank 24 and enters it via an inlet port 12 to which the gas recycling line 11 is fluidically connected.

[0037] The gas purification system 1 therefore constitutes a unit for purifying exhaled gases making it possible to purify and then recycle exhaled gases rich in O 2 by removing the CO 2 and possibly the water vapor (H 2 O) that they contain, instead of releasing them into the atmosphere, as is usually the case, and thus wasting the oxygen that is still present in large quantities, typically at least 90% vol. approximately.

[0038] As illustrated in Fig. 2 , the oxygen generation unit 30 comprises one or more electrochemical separation modules 316 making it possible to supply the oxygen-rich respiratory gas, typically pure or almost pure oxygen, for example having a purity >99.95% vol., to the main gas delivery line 23, i.e. the patient circuit, then to the buffer tank 24 supplying the respiratory interface 21, such as a face mask or the like, so as to administer the respiratory gas, i.e. oxygen, to the patient P, during his inspiratory phases.

[0039] An example of an electrochemical separation module 316 usable in the context of the present invention is described by the document: 49th International Conference on Environmental Systems; 7-11 July 2019; Boston (MA); ICES-2019-379; Solid State Electrochemical Oxygen Separation and Compression; M. Reisert et al.; p. 1-10 .

[0040] Fig. 2 schematizes the architecture and operation of an embodiment of the O23 generation unit integrating an electrochemical separation module 316.

[0041] This O23 generation unit comprises first control means 350, 351 comprising for example a first electronic control card 350 and a first control unit 351 with microprocessor(s), typically one (or more) microcontroller(s). The electromechanical elements of the O23 generation unit are electrically powered and controlled by the first control means 350, 351.

[0042] The O23 generation unit further comprises a first internal gas line 3100 comprising an upstream portion called the intake duct 310 and a downstream portion called the inlet duct 315; and a second internal gas line 3200 comprising an upstream portion called the second outlet duct 325 and a downstream portion called the exhaust duct 330.

[0043] Heat exchange means 312, such as a heat exchanger, 312 are arranged on the first internal gas line 3100 so that the gas flow conveyed by the first internal gas line 3100 can pass through these heat exchange means 312, before reaching gas heating means 313 arranged on the inlet duct 315, that is to say downstream of the heat exchange means 312 considering the direction of circulation of the gas flow.

[0044] The first internal gas line 3100 is connected to the gas purification system, via a first interconnection conduit 31, e.g. pipe, conduit, line or the like, while the second internal gas line 3200 is connected to the gas purification system, via a second interconnection conduit 33, e.g. pipe, conduit, line or the like, as detailed below.

[0045] The internal intake duct 310 of the first internal gas line 3100 of the O23 generation unit comprises gas suction means 311, such as a blower-type fan device or the like, for sucking in the gas supplied by the first interconnecting duct 31, as explained below, to circulate it in the internal intake duct 310 and then through the heat exchange means 312, in which a heat exchange between the gas flow and the waste gas flow can take place, as explained below.

[0046] After passing through the heat exchange means 312, the gas flow is recovered and conveyed by the inlet conduit 315 of the first internal gas line 3100, to gas heating means 313, such as a gas heater or a similar heating device.

[0047] The heat exchange means 312 are therefore arranged, on the first internal gas line 3100, between the gas suction means 311 and the gas heating means 313.

[0048] As detailed below, the first internal gas line 3100 makes it possible to bring the air flow supplied by the gas purification system 1, via a first interconnection conduit line 31, to the electrochemical O 2 separation module(s) 316 of the O 2 3 generation unit, which are arranged downstream of the gas heating means 313 on the first internal gas line 3100.

[0049] The gas heating means 313, for example an electric gas heating device, are configured to preheat the gas flow, namely air, supplied by the inlet conduit 315 of the first internal gas line 3100 to a temperature above 600°C before it is supplied to the electrochemical O 2 separation module(s) 316. According to another embodiment, several electrochemical O 2 separation modules 316 are provided, for example arranged in parallel.

[0050] The or each O2 separation module 316 comprises one or more ceramic membranes doped with one or more electrolytes which, under the action of heat and an electrical potential applied by the first control card 350, allows the O2 molecules contained in the air flow coming from the gas purification system 1, to pass through the ceramic membrane(s) and to be recovered in the first outlet conduit 320 which then feeds the main gas delivery line 23 of the installation 50 of the invention, with a flow of high purity oxygen, i.e. > 99.50% vol., generally with a purity of the order of 99.90% vol. to 99.95% vol.

[0051] The air supplying the O2 separation module(s) 316 is captured from the atmosphere via an air intake duct 102 of the gas purification system 1, which is connected to the ambient atmosphere, then conveyed through the gas purification system 1, through one or other of the adsorbers 130-132, as explained below and visible in Fig. 3 .

[0052] In other words, the or each O2 separation module 316 comprises: a gas inlet 316a through which the gas conveyed, i.e. the air flow, by the first internal gas line 3100 enters the or each O2 separation module 316, before its separation by the ceramic membrane(s) located therein; a first outlet 316b supplying the first outlet conduit 320 with a flow of high-purity oxygen produced by the ceramic membrane(s); and a second outlet 316c supplying the second internal gas line 3200 with waste gas which has not passed through, i.e. has been retained, by the ceramic membrane(s).

[0053] The oxygen flow conveyed by the outlet conduit 320 is formed of oxygen of (very) high purity, for example at least 99.95% vol. to approximately 99.99% vol., at room temperature, i.e. of the order of 10 to 30°C, i.e. oxygen containing no or negligible quantities of other compounds as possible unavoidable impurities, such as nitrogen (N 2 ) and / or argon (Ar). In other words, the ceramic membrane(s) are designed to allow only the oxygen molecules to pass through, which are then recovered and supplied by the outlet conduit 320 to the main gas delivery line 23 which delivers this oxygen flow to the buffer tank 24, as already explained.

[0054] The buffer tank 24 is preferably provided with an exhaust valve 26 allowing any excess O2 to be discharged into the ambient atmosphere when the buffer tank 24 is full of oxygen, i.e. completely filled.

[0055] In all cases, recovering the majority of the O2 forming the compound which is highly prevalent in the gases exhaled by patient P (i.e. CO2 / O2 mixture), and recycling it after purification, makes it possible to avoid wasting it, and therefore to limit the flow of oxygen supplied by the O23 source.

[0056] For example, the metabolic consumption of O 2 of a human being is considered to be of the order of 0.5 L / min. In other words, if a patient has a minute ventilation of 10 L / min, i.e. inhales 10L of gas in 1 minute, of pure O 2, i.e. with a content of 100% O 2 , then 9.5 L of O 2 are exhaled, the remainder (0.5 L) is made up of CO 2 and water vapor. Therefore, the gas purification system 1 can recover approximately 9.5L of O 2 . Furthermore, thanks to the O23 generation unit providing an O2 flow rate of 1 L / min and the recycling of the O2 contained in the expired gas and its mixing with the O2 coming from the O23 generation unit, the O2 flow rate obtained exceeds the patient's minute ventilation.

[0057] Furthermore, almost all of the other compounds present in the air supplied by the first internal gas line 3100, such as nitrogen, argon and / or other possible compounds, exit the O 2 separation module 316 via the second outlet 316c in the form of a waste gas and are then conveyed by the second internal gas line 3200 to serve as regeneration gas for the adsorbers of the gas purification system 1, as detailed below.

[0058] More specifically, due to the combination of the preheated gas and the Joule effect manifested in the or each O 2 separation module 316, the waste gas containing the other gaseous compounds (N 2 , Ar, etc.), which is at a temperature of the order of 850°C, leaves the O 2 separation module 316 through the second outlet conduit 325 forming the upstream portion of the second internal gas line 3200, which conveys the waste gas through the heat exchange means 312, such as a heat exchanger, which is also arranged on the second internal gas line 3200.

[0059] In other words, the heat exchange means 312 are crossed by the first internal gas line 3100 and the second internal gas line 3200, as seen in Fig. 2 so as to be able to operate between the flows conveyed by these lines, a heat exchange preferably in counter-current. The waste gas flow then leaves through the exhaust duct 330 forming the downstream portion of the second internal gas line 3200, and is then conveyed to the gas purification system 1, as detailed below.

[0060] The heat exchange means 312 are configured to recover a portion of the heat energy, i.e. calories, from the hot waste gas which is typically at a very high temperature above 500°C, for example approximately 850°C, supplied by the second outlet duct 325 of the second internal gas line 3200 and to supply it to the gas, i.e. air, circulating in the inlet duct 310 of the first internal gas line 3100 to preheat it and thus optimize the electrical consumption of the O23 generation unit. In other words, a heat exchange takes place within the heat exchange means 312, preferably countercurrent, between the flow of gas circulating in the inlet duct 310 and the flow of waste gas supplied by the second outlet duct 325.

[0061] After heat exchange, i.e. from the heat / calorie exchanger, the waste gas discharged through the exhaust duct 330 is at a lower but still high temperature, typically of the order of approximately 250 to 300°C, and contains less than 21% vol. of O 2 since oxygen present in the initial flow has migrated through the O 2 separation module 316 and has been discharged successively through the first outlet duct 320 and the main gas delivery line 23 to the buffer tank 24. Indeed, as already indicated, the first outlet duct 320 of the O 2 3 generation unit is fluidically connected to the main gas delivery line 23, including the buffer tank 24, as illustrated in Fig. 1 .

[0062] The O2 flow rate provided by the O23 generation unit is usually low, for example of the order of 1 L / min, so as to limit the weight and size of the O23 generation unit but also its electrical consumption.

[0063] All components of the O23 generation unit are advantageously arranged in a rigid protective casing or housing 300.

[0064] Since the gas purification system 1 is fluidically connected to the O 2 3 generation unit by means of two parallel conduits, namely a first interconnecting conduit 31 and a second interconnecting conduit 33 fluidically connected, respectively, to the intake conduit 310 and to the exhaust conduit 330, it is not only possible to supply the O 2 3 generation unit with air having passed through the gas purification system 1, in particular one or the other of its adsorbers 130-132 in order to cool them as explained below, but also to be able to use the waste gas generated by the O 2 3 generation unit as a regeneration fluid for said adsorber(s) 130-132 in order to regenerate them as detailed below.

[0065] Fig. 3 schematizes an embodiment of the gas purification system 1, also called “exhaled gas purification unit”, forming part of the installation 50 for supplying respiratory gas, i.e. oxygen, according to the invention, as illustrated in Fig. 1 .

[0066] In addition to the elements already mentioned, the gas purification system 1 or exhaled gas purification unit comprises second control means 150, 151, typically a second electronic control card 150 and a second control unit 151 with microprocessor(s), typically one or more microcontrollers.

[0067] All the electromechanical elements of the purification system 1 are electrically powered and controlled by the second control means 150, 151. The second control means 150, 151 are themselves electrically powered by a source of electric current (not shown), for example a connection to the mains current (110 / 220V) of the electric cord and connection plug type, or one (or more) electric power supply batteries, preferably rechargeable, and / or a current transformer.

[0068] The second control means 150, 151 control in particular the control valves, namely the rotary valves 110-112, 140-142.

[0069] More precisely, the second control card 150, i.e. an electronic card, preferably integrates the microprocessor control unit 151 and is configured to control and also analyze the signals coming from the various components of the exhaled air purification unit 1, such as valves, pump, sensors, etc.

[0070] The second control card 150 and the other components of the purification unit 1 are also arranged in a rigid external casing or housing 15, for example made of polymer.

[0071] The exhaled gas purification unit 1 comprises an inlet conduit or passage 100 with an inlet orifice which is fluidically connected to the gas recovery line 10, also called an expiratory circuit, such as a conduit, a flexible pipe or the like, used to collect and convey the gas exhaled by the patient (i.e. O 2 / CO 2 mixture) to the outlet of the respiratory interface 21, as explained above.

[0072] The gas recovery line 10 is fluidically connected, via its downstream end, to the inlet conduit 100 via a connection system comprising, for example, reciprocal connectors of the male / female type, making it possible to ensure a mechanical and fluidic connection and also to the respiratory interface 21, such as a face mask for example, via its upstream end, in order to collect the gas exhaled by the patient P.

[0073] The gas exhaled (i.e. CO / O 2 mixture) by the patient, which essentially contains O 2 (approximately 90 to 95% vol.) and CO 2 (approximately 5% vol.), or even water vapor and / or other unavoidable impurities, is purified in the gas purification system 1 by eliminating the CO 2 and preferably the water vapor present, so as to obtain a purified gas containing a high proportion of oxygen, for example at least 99% to 99.9% vol. of oxygen.

[0074] In other words, the entry of the gas exhaled by the patient into the exhaled gas purification unit 1 is done via the upstream portion or inlet portion of the inlet conduit 100 of the exhaled gas purification unit 1.

[0075] The inlet conduit 100 further comprises a flow sensor 101, typically a mass flow sensor and, downstream of this flow sensor 101, the inlet conduit 100 branches at a branch site 100a into three sub-conduits, preferably identical, respectively called inlet sub-conduits 1000, 1001, 1002. The first inlet sub-conduit 1000 opens onto a first rotary valve 110, the second inlet sub-conduit 1001 opens onto a second rotary valve 111 and the third inlet sub-conduit 1002 opens onto a third rotary valve 112. The rotary valves 110, 111 and 112 are identical and their operation will be explained below.

[0076] Furthermore, the exhaled gas purification unit 1 comprises an air intake duct 102 connected to the ambient atmosphere, via an air inlet port 102c and subdividing (at 102a, 102b) into a first intake sub-duct 1020, a second air intake sub-duct 1021 and a third intake sub-duct 1022.

[0077] The air intake duct 102 makes it possible to sample the air which is, after passing through the adsorber(s) 130-132 of the exhaled gas purification unit 1, as explained below, sent to the O 2 3 generation unit via the interconnection duct 31 fluidly supplying the intake duct 310 of the O 2 3 generation unit with the air used in the O 2 separation module 316 to produce (quasi)pure oxygen. The first, second and third intake sub-ducts 1020, 1021, 1022 open respectively onto the first, second and third rotary valves 110, 111, 112.

[0078] Similarly, the exhaled gas purification unit 1 comprises an exhaust duct 103 connected to the ambient air at an evacuation port 103c, which is formed by joining (at 103a and 103b) three sub-ducts 1030-1032, namely respectively a first, a second and a third exhaust sub-duct 1030, 1031, 1032. As before, the first, second and third exhaust sub-ducts 1030, 1031, 1032 open respectively onto the first, second and third rotary valves 110, 111, 112. The exhaust duct 103 has no fluid communication other than those connecting it to its sub-ducts.

[0079] Each of the sub-ducts from the inlet 100, intake 102 and exhaust 103 ducts opens into one of the first, second or third rotary valves 110, 111 or 112. For example, the first inlet sub-duct 1000 of the inlet duct 100, the first intake sub-duct 1020 of the intake duct 102 and the first exhaust sub-duct 1030 of the exhaust duct 103 open into the first rotary valve 110. The same applies to the other sub-ducts 1001, 1021, 1031; 1002, 1022, 1032 and other valves 111; 112, respectively.

[0080] Fig. 4 is an exploded schematic view of the first rotary valve 110. It comprises two main elements assembled together, namely a central element 111 forming a solid cylinder crossed by an angled conduit 112 connecting a lateral orifice 112a to a central orifice 112b; and a peripheral element 115 forming a “cover”. It comprises a bottom wall 115-1 in the shape of a disc and a peripheral wall 115-2 forming a peripheral annular border around the bottom wall. The bottom wall 115-1 and the peripheral wall 115-2 delimit a central space or housing 116 configured and sized to house the central element 111, i.e. solid cylinder, after assembly. The peripheral element 115 has three lateral recesses 115a, 115b and 115c arranged in the annular border and in fluid communication with the central housing 116.

[0081] The second and third rotary valves 111, 112 have identical structures and are therefore not detailed.

[0082] Fig. 5 illustrates the assembly of the central element 111 and peripheral element 115 forming a “cover” so as to thus obtain the first rotary valve 110. In this configuration, the lateral orifice 112a of the conduit 112 of the solid cylinder forming the central element 111 is opposite the lateral orifice 115a of the peripheral element 115 forming a cover. Conversely, the lateral orifices 115b, 115c of the peripheral element 115 are hidden by the lateral wall 113, i.e. the peripheral wall 115-2, of the central element, i.e. the solid cylinder. The lateral orifice 115a is therefore in fluid communication with the central orifice 112b of the conduit 112, while the lateral orifices 115b, 115c of the peripheral element 115 are “blocked” by the lateral wall 113 of the central element 111.

[0083] The absence of leaks between the peripheral element 115, the central element 111 and their respective orifices can be ensured by integrating seals (not shown), for example O-rings, around the lateral orifices 115a, 115b, 115c of the peripheral element 115.

[0084] Furthermore, the ports 115a, 115b, 115c of said first rotary valve 110 are respectively connected, for example force-fitted, welded or otherwise, to the first inlet sub-duct 1000 of the inlet duct 100, to the first intake sub-duct 1020 of the intake duct 102 and to the first exhaust sub-duct 1030 of the exhaust duct 103.

[0085] Furthermore, the central orifice 112b of the bent conduit 112 of the central element 111 is itself connected to a first conduit 120 as illustrated in Fig. 3 This connection is of the circular type in the sense that the central element 111 having a solid cylinder shape, can perform a rotational movement around the axis defined by the central orifice 112b, physically connected to the first conduit 120. Such a rotational movement can be obtained by mechanical coupling to a rotary actuator (not shown), for example a stepper motor controlled by the second control card 150, then allowing the central element 111 to perform a rotational movement in the peripheral element 115.

[0086] With appropriate control by the second control board 150, the first rotary valve 110 can be configured to select a fluid configuration, i.e., on the Fig. 5 , to fluidly connect the first inlet sub-duct 1000 of the inlet duct 100 to the first duct 120, while the first intake sub-duct 1020 of the intake duct 102 and the first exhaust sub-duct 1030 of the exhaust duct 103 are blocked and cannot convey gas. In other words, the first rotary valve 110 is configured for example to provide fluid communication between the inlet duct 100 and the first duct 120, and therefore all of the gas flowing in the inlet duct 100 is conveyed into the first duct 120.

[0087] Such a configuration may be modified by the second control board 150 so as to fluidically connect the first intake sub-duct 1020 of the intake duct 102 to the first duct 120, or the first exhaust sub-duct 1030 of the exhaust duct 103 to the same first duct 120.

[0088] In other words, depending on the configuration of the first rotary valve 110, the first conduit 120 is fluidically connected either to the inlet conduit 100, to the intake conduit 102, or to the exhaust conduit 103.

[0089] As indicated previously, the first, second and third rotary valves 110, 111, 112 are identical. It thus appears that the second rotary valve 111 can, depending on the configuration determined by the second control card 150, put a second conduit 121 into fluidic connection with either the inlet conduit 100, the intake conduit 102, or the exhaust conduit 103. By analogy, the third rotary valve 112 can, depending on the configuration determined by the second control card 150, put a third conduit 122 into fluidic connection with either the inlet conduit 100, the intake conduit 102, or the exhaust conduit 103.

[0090] Furthermore, as illustrated on Fig. 3 , the gas purification system 1 comprises several adsorbers 130-132, also called adsorption cartridges, each containing one or more adsorbents used to purify the exhaled gas (i.e. O 2 / CO 2 mixture), preferably 3 adsorbers 130-132 arranged in parallel.

[0091] More specifically, arranged in the first conduit 120 is a first cartridge or adsorber 130, having a first upstream port 130a, i.e. an inlet orifice, and a first downstream port 130b, i.e. an outlet orifice. Similarly, a second cartridge or adsorber 131 is arranged in the second conduit 121 and has a second upstream port 131a and a second downstream port 131b, and a third cartridge or adsorber 132 is arranged in the third conduit 122 and has a third upstream port 132a and a third downstream port 131b.

[0092] The first, second and third cartridges 130, 131, 132 are adsorption containers arranged in parallel on the path of the gas conveyed by the first, second and third conduits 120-122, respectively, namely the exhaled gas (i.e. O 2 / CO 2 mixture) to be purified to produce oxygen.

[0093] To this end, the cartridges 130-132 each contain one or more adsorbents, i.e. molecular sieves, preferably arranged in a bed of absorbent particles, for example one (or more) zeolite-type adsorbents, such as a 13X zeolite, and / or a silicate-type adsorbent. For example, each cartridge 130-132 is sized to contain approximately 500 g of 13X zeolite and silicate particles. The adsorbent particles are typically beads, extrudates or the like. In all cases, one or more adsorbents are chosen which can preferentially adsorb or trap CO2, or even water vapour, i.e. which have a higher selectivity for CO2 (and preferably water) than for oxygen, so as to produce a purified flow containing an oxygen concentration higher than that in the gas exhaled by the patient, i.e. before its purification.

[0094] The adsorbent allows the oxygen flow to be concentrated by eliminating the majority, or even (almost) all, of the other species present there, typically CO2 and water, and / or other unavoidable impurities.

[0095] Of course, other adsorbent materials, such as MOFs (Metal Organic Framework) or others can be used as a replacement or supplement to increase the CO2 adsorption capacity and / or selectivity.

[0096] When the gas flow (i.e. O2 / CO2 mixture) has passed through one or other of the cartridges 130-132, it emerges in the form of purified gas, namely a flow of high-purity oxygen (>95% vol. approx.), through one of the outlet orifices or downstream ports 130b-132b, before being conveyed through one or other of the first, second and third conduits 120-122 to respectively a fourth rotary valve 140, a fifth rotary valve 141 and a sixth rotary valve 142, which are identical or similar to the first rotary valve 110.

[0097] The exhaled gas purification unit 1 further comprises an outlet conduit 107 resulting from the joining (at 107a) of three sub-conduits, namely a first outlet sub-conduit 1070, a second outlet sub-conduit 1071 and a third outlet sub-conduit 1072 which are respectively fluidically connected to the fourth rotary valve 140, to the fifth rotary valve 141 and to the sixth rotary valve 112.

[0098] The outlet conduit 107 is fluidically connected to the gas recycling line 11 to supply it with oxygen produced by the exhaled gas purification unit 1 and allow it to be conveyed via said gas recycling line 11 to the buffer tank 24, as already explained.

[0099] In fact, the gas inlet conduit 100 and the outlet conduit 107 are part of a gas recycling circuit 502 internal to the gas purification system 1 which makes it possible to convey the gas flows, namely the flow of exhaled gas to be purified, i.e. O 2 / CO 2 mixture, and the flow of purified gas, i.e. O 2 ), from the gas inlet conduit 100 to the outlet conduit 107.

[0100] The inlet conduit 100 is supplied with O2 / CO2 mixture by the gas recovery line 11, while the outlet conduit 107 is fluidically connected to the gas recycling line to supply it with oxygen, i.e. recycled gas, produced by the exhaled gas purification unit 1.

[0101] The gas recycling circuit 502 comprises air ducts 100, 107, 120-122, and at least one adsorber 130-132, preferably the adsorbers 130-132, and control valves 110-112, 140-142, in particular rotary valves.

[0102] In addition, the exhaled gas purification unit 1 also comprises an air extraction duct 108 comprising an air outlet port 108c, connected to the first interconnecting duct 31 of Fig. 2 , via a connection system comprising, for example, reciprocal male / female connectors providing a mechanical and fluid connection.

[0103] The extraction duct 108 also results from the joining (at 108a, 108b) of three sub-ducts, namely a first extraction sub-duct 1080, a second extraction sub-duct 1081 and a third extraction sub-duct 1082, which are respectively fluidically connected, i.e. open out, to the fourth rotary valve 140, to the fifth rotary valve 141 and to the sixth rotary valve 142.

[0104] The extraction conduit 108 is fluidically connected, via the first interconnecting conduit 31, to the inlet conduit 310 of the O 2 3 generation unit to supply it with the air which is used in the O 2 separation module 316 to produce (near)pure oxygen.

[0105] Finally, the exhaled gas purification unit 1 also comprises a regeneration conduit 109 fluidically connected to the second interconnection conduit 33 of Fig. 2 which is itself fluidically connected to the exhaust duct 330 of the O 2 3 generation unit, so as to be able to collect and convey the waste gas coming from the O 2 3 generation unit, as explained below.

[0106] Here again, the regeneration conduit 109 results from the joining (at 109a, 109b) of three sub-conduits, namely a first regeneration sub-conduit 1090, a second regeneration sub-conduit 1091 and a third regeneration sub-conduit 1092, which are respectively fluidically connected, i.e. open, to the fourth rotary valve 140, to the fifth rotary valve 141 and to the sixth rotary valve 142.

[0107] Since the different rotary valves and the different conduits and sub-conduits arranged on either side of the first, second and third cartridges 130, 131, 132 are identical, depending on the configuration determined by the second control card 150: the fourth rotary valve 140 can fluidically connect the first conduit 120 with either the outlet conduit 107, the extraction conduit 108, or the regeneration conduit 109. the fifth rotary valve 141 can fluidically connect the second conduit 121 with either the outlet conduit 107, the extraction conduit 108, or the regeneration conduit 109. the sixth rotary valve 142 can fluidically connect the third conduit 122 with either the outlet conduit 107, the extraction conduit 108, or the regeneration conduit 109.

[0108] The operation of the exhaled gas purification unit 1 of the O2 supply plant illustrated in Fig. 1 is described below, sequentially by successively configuring the rotation valves of the exhaled gas purification unit 1.

[0109] It is considered that, in the initial configuration, that is to say fixed by the control card 150 controlling the different rotary valves of the expired gas purification unit 1: the first rotary valve 110 provides fluid communication between the inlet conduit 100 and the first conduit 120. The fourth rotary valve 140 provides fluid communication between the first conduit 120 and the outlet conduit 107. There is thus fluid communication between the inlet conduit 100 and the outlet conduit 107. the second rotary valve 111 provides fluid communication between the intake conduit 102 and the second conduit 121. The fifth rotary valve 141 provides fluid communication between the second conduit 121 and the extraction conduit 108. There is thus fluid communication between the intake conduit 102 and the extraction conduit 108. the third rotary valve 112 provides fluid communication between the exhaust conduit 103 and the third conduit 122. The sixth rotary valve 142 provides fluid communication between the third conduit 122 and the regeneration conduit 109.There is thus a fluid communication between the exhaust duct 103 and the regeneration duct 109.

[0110] The operation of the exhaled gas purification unit 1 is detailed in relation to first the first cartridge 130, then the second and third cartridges 131, 132.

[0111] As already stated, the gas exhaled by the patient P (i.e. O2 / CO2 mixture), which contains a high O2 content, for example of the order of 90% to 95% by volume, but also CO2 (approx. 5% by volume) and generally water vapour, passes through the gas recovery line 10 forming an expiratory circuit, before being admitted into the expired gas purification unit 1 of Fig. 3 , via the inlet conduit 100.

[0112] Due to the pneumatic configurations imposed by the control card 150, the inlet conduit 100 is fluidically connected to the outlet conduit 107 via the first conduit 120, on which the first cartridge 130 or adsorber is arranged. Thus, the gas passing through the inlet conduit 100 is directed into the first cartridge 130, via its first upstream port 130a, to be freed of CO 2 and preferably of the water vapor that it contains, that is to say that the adsorbent(s) filling the first cartridge or adsorber 130 capture, that is to say retain / trap the CO 2 molecules and preferably of water vapor, while allowing the O 2 to pass through, that is to say without adsorbing it.

[0113] For example, the CO2 and water vapor adsorption capacity and / or selectivity of zeolites, in particular zeolite 13X, or silicates is greater than the O2 adsorption capacity / selectivity so that these CO2 and water vapor compounds are preferentially trapped / adsorbed, while oxygen can freely pass through the adsorbent bed without being retained or very little.

[0114] Thus, the purified gas leaving the first cartridge 130, via the first downstream port, 130b is purified of CO2 and water vapor, is an oxygen flow containing essentially oxygen, namely typically formed of more than 99.5% oxygen.

[0115] After leaving the exhaled gas purification unit 1, it is recovered and conveyed through the gas recycling line 11 forming an exhaust circuit, having previously passed through the first conduit 120 located downstream of the first cartridge 130 and the outlet conduit 107, as already explained.

[0116] The purified gas can then be reinjected into the main gas delivery line 23, via the reservoir 24 into which it enters via the additional port 12. This flow of purified gas which contains oxygen at high concentration (eg >99.5%) is therefore mixed, within the reservoir 24, with oxygen (eg 100%) coming from the oxygen source 3 so as to obtain a mixture of oxygen of very high purity (i.e. close to 100% vol), which can then be conveyed to the patient P and administered to him via the respiratory interface 21 in order to be re-inhaled. In other words, the flow of purified gas replaces a portion of the oxygen coming from the oxygen source 3, which makes it possible to limit the consumption of oxygen coming from said oxygen source 3 and also the waste of oxygen by recycling the exhaled gas which would normally be released into the atmosphere.

[0117] The gas purification system 1 of Fig. 3 of the gas supply installation 50 according to the invention of Fig. 1 operates cyclically, due to the use of adsorbent(s) in adsorbers 130-132 which needs to be regenerated in order to desorb / release the compounds that have been trapped, namely CO2 and water vapor from the patient's expiratory phases.

[0118] In fact, the adsorbent (or adsorbents) has a maximum adsorption capacity beyond which the adsorbent is saturated, i.e. it can no longer capture CO2 molecules, or even water molecules, and these molecules can then pass through the adsorbent with the oxygen produced and end up in the "purified" gas, which is not desirable.

[0119] In order to avoid such a situation of saturation of the adsorbent, and so that the patient P cannot re-inhale CO2 (with oxygen) and therefore avoid a dangerous situation for him, it is advisable to periodically regenerate each adsorbent in order to rid it of the compounds which are adsorbed / retained there, in particular CO2.

[0120] According to one embodiment, the maximum adsorption capacity of the first cartridge 130, i.e. the maximum volume of CO 2 that can be retained therein, i.e. captured, is known and stored within the microcontroller 151 or elsewhere. By measuring the total volume of exhaled gas that has been admitted into the exhaled gas purification unit 1, by means of the first flow sensor 101, and by considering a CO 2 concentration of the order of 5% vol., the microcontroller 151 is able to determine that the first cartridge 130 is close to reaching saturation. The same procedure is followed for the other cartridges 131, 132, i.e. the other adsorbers.

[0121] Of course, according to other embodiments, the evaluation of the saturation rate of the cartridges 130-132, i.e. the adsorbers, could be carried out differently, for example by measuring the temperature of the adsorbents or by integrating a measurement of the CO2 content in the outlet conduit 107. According to yet another embodiment, the regeneration of the cartridges 130-132 could also be carried out after a given duration or in any other way.

[0122] When the first cartridge 130, i.e. the first adsorber, or another cartridge 131, 132, reaches saturation, the microcontroller 151 controls the second rotary valve 111 and the fifth rotary valve 141 in order to switch to an unsaturated and / or regenerated cartridge, in order to allow the system to continue to purify the gases exhaled by the patient P, while the saturated cartridge or adsorber is regenerated.

[0123] The second rotary valve 111 provides a fluid connection between the inlet conduit 100 and the second conduit 121, while, at the same time, the fifth rotary valve 141 provides a fluid connection between the same second conduit 121, in particular its downstream portion located downstream of the second downstream port 131b of the second cartridge 131, and the outlet conduit 107. At the same time, the microcontroller 151 controls the first rotary valve 110 and the fourth rotary valve 140 so as to put the exhaust conduit 103 and the first conduit 120 into fluid connection respectively, as well as the downstream portion of the first conduit 120, i.e. downstream of the first downstream port 130b of the first cartridge 130, and the regeneration conduit 109.

[0124] The microcontroller 151 also controls the third rotary valve 112 and the sixth rotary valve 142 so as to put into fluidic connection respectively the intake conduit 102 and the third conduit 122, as well as the downstream portion of said third conduit 122 and the extraction conduit 108.

[0125] Thus, when the first cartridge 130 is saturated, it must be regenerated. Conventionally, during regeneration of an adsorbent bed, a dry gas, i.e. one devoid of moisture, i.e. water vapor, for example N 2 from a bottle, is heated to a high temperature, for example greater than 250°C and passes through the adsorbent. By appropriately managing the temperature profile, it is possible to regenerate the adsorbent.

[0126] However, in the context of the present invention, regeneration of this type is not suitable due to the absence of any source of dry gas on the site of use, typically in a hospital or the like. In addition, the fact of having to bring the gas to a high temperature results in technical complexity and therefore induces additional cost as well as significant electricity consumption.

[0127] In the context of the invention, the waste gas stream from the O23 generation unit is used to carry out the regeneration.

[0128] Indeed, we understand, in view of Fig. 2 , that the exhaust duct 330 of the O 2 3 generation unit conveys a gas depleted in O 2 (i.e. with a concentration of less than 21% vol.), typically <19% O 2 , at high temperature, i.e. at least approximately 300°C.

[0129] The exhaust duct 330 is fluidically connected to the second interconnecting duct 33 and to the regeneration duct 109 of the exhaled gas purification unit 1, the waste gas flow from the O 2 3 generation unit is brought to the regeneration duct 109 and is then directed into the first duct 120 of the first cartridge 130, due to the pneumatic configuration of the fourth rotary valve 140.

[0130] This waste gas will then be used as a regeneration gas since it will enter the first cartridge 130 via the first downstream port 130b, desorb part of the CO2 and water vapor adsorbed on the adsorbent contained in the first cartridge 130 and exit through the first upstream port 130a, carrying with it the desorbed compounds, i.e. CO2 and possibly H2O.

[0131] In other words, the regeneration flow exiting the first cartridge 130 via the first upstream port 130a is formed from waste gas enriched in CO2 and preferably in water vapor.

[0132] Although this waste gas serving as regeneration gas, circulating in the regeneration conduit 109, contains traces (i.e. very low contents) of water vapor and CO 2 , since it emanates from the ambient air having been supplied to the O 2 3 generation unit to produce oxygen, the high temperature of this waste gas, i.e. at least approximately 300°C, makes it possible to ensure complete desorption of the first cartridge 130 without also causing temporary adsorption of these traces of water vapor and CO 2 .

[0133] The gas flow circulating in the upstream portion of the first conduit 120 then arrives at the first rotary valve 110 and, due to the pneumatic configuration of said first rotary valve 110, takes the exhaust conduit 103, to be evacuated to the ambient air via the outlet port 103c of the exhaust conduit 103.

[0134] In other words, regeneration is obtained by the flow of heated waste gas which is carried out counter-currently, i.e. in the opposite direction to the direction of circulation of the gas during the adsorption stage, i.e. oxygen production.

[0135] The regeneration flow leaving the adsorber during regeneration is discharged to the atmosphere through the exhaust duct 103.

[0136] In other words, the gas purification system 1 comprises an internal regeneration circuit 501 for conveying the waste gas supplied to it by the oxygen generation unit 50, via the second interconnecting conduit 33, from the regeneration conduit 109 to the exhaust conduit 103 connected to the atmosphere in order to allow the regeneration gas flow to be evacuated therein, after passing through at least one adsorber 130-132. The regeneration circuit 501 therefore comprises air passages or conduits 103, 109, 120-122 and at least one adsorber, preferably the adsorbers 130-132, and also control valves, in particular the rotary valves 110-112, 140-142.

[0137] While the first cartridge 130 is in the regeneration phase, the gas passing through the inlet conduit 100 is directed into the second cartridge 131, via its second upstream port 131a, to be freed from CO2 and water vapor and to produce a flow of oxygen, as already explained, exiting the second cartridge 131, via the second downstream port 130b, having an oxygen content generally of more than 99.5% vol.

[0138] After leaving the expired gas purification unit 1, it is recovered and conveyed via the gas recycling line 11, having previously passed through the second conduit 121 located downstream of the second cartridge 131 and the outlet conduit 107. This purified gas is then reinjected into the main gas conveying line 23, via the buffer tank 24, as already detailed.

[0139] As before, the microcontroller 151 can then determine that the second cartridge 131 also reaches saturation and then controls the third rotary valve 112 and the sixth rotary valve 142 in order to switch to a non-saturated and / or regenerated cartridge, allowing the gases exhaled by the patient P to continue to be purified.

[0140] At this time, the third rotary valve 112 makes a fluid connection between the inlet conduit 100 and the third conduit 122, while at the same time, the sixth rotary valve 142 makes a fluid connection between the same third conduit 122, in particular its downstream portion located downstream of the third downstream port 132b of the third cartridge 132, and the outlet conduit 107.

[0141] At the same time, the microcontroller 151 controls the first rotary valve 110 and the fourth rotary valve 140 so as to fluidically connect respectively the intake duct 102 and the first duct 120, as well as the downstream portion of the first duct 120, i.e. downstream of the first downstream port 130b of the first cartridge 130, and the extraction duct 108 so as to allow ambient air to enter the purification system 1 via the intake duct 102 and exit via the extraction duct 108 which feeds the interconnection duct 31 bringing the air flow, via the intake duct 310, to the oxygen generation unit 30, where it is separated within one (or more) electrochemical separation modules 316 in order to produce the high-purity oxygen flow and also the waste gas flow used for the regeneration of the adsorbents, as already explained.

[0142] In fact, the air is conveyed within the exhaled gas purification unit 1 in an internal air circuit 500 comprising air ducts or passages, in particular the intake duct 102, the extraction duct 108 and all the intermediate connecting ducts 120-122, and elements arranged on these ducts 120-122, in particular the adsorber(s) 130-132 and one or more control valves, in particular the rotary valves 110-112; 140-142.

[0143] The air circulating in the air circuit 500 therefore passes through at least one adsorber 130-132 before being evacuated through the extraction duct 108 and sent to the oxygen generation unit 30 via the first interconnection duct 31.

[0144] This is advantageous because the air flow taken from the atmosphere is at room temperature, i.e. generally around 15 to 30°C. It can therefore cool the adsorbent(s) that have been regenerated by the hot waste gas.

[0145] Although the air stream may contain atmospheric CO2 as an impurity, the amount of CO2 present is negligible (max. approx. 0.005% vol.) compared to that present in the exhaled gas to be purified (i.e. approx. 5% vol.) and does not impact the performance of the adsorbent(s).

[0146] Similarly, the amount of water vapor (i.e. humidity) that can be found in the air flow as an impurity is also low and, in any case, insufficient to negatively impact, i.e. significantly, the overall adsorption capacity of the adsorbent(s).

[0147] In any case, the adsorbers and the amount of adsorbent in them can be sized to take into account atmospheric impurities and their potential negative influence on the adsorbent(s).

[0148] Alternatively, an additional dedicated adsorbent bed can be provided to trap these impurities.

[0149] The microcontroller 151 also controls the second rotary valve 111 and the fifth rotary valve 141 so as to put the exhaust duct 103 and the second duct 121 into fluidic connection respectively, as well as the downstream portion of the second duct 122 and the regeneration duct 109.

[0150] The exhaled gas (i.e. O2 / CO2 mixture) passing through the inlet conduit 100 is then directed into the third cartridge 132, via the third upstream port 131a, to be freed of CO2 and preferably of water vapor and to exit the third cartridge 131 to pass through the outlet conduit 107 via the third conduit 122.

[0151] Again, after leaving the exhaled gas purification unit 1, the gas flow formed from oxygen is recovered and conveyed to the patient P via the gas recycling line 11 and the successive conveying lines.

[0152] At the same time, the high-temperature waste gas circulating in the regeneration conduit 109 is directed into the second conduit 121 of the second cartridge 131, due to the pneumatic configuration of the fifth rotary valve 141. This waste gas will enter it, via the second downstream port 131b and entrain a portion of the CO2 and water vapor that the cartridge 131 has trapped on its adsorbent, to exit via the second upstream port 131a. The flow propagating in the upstream portion of the second conduit 121 then opens onto the second rotary valve 111 and, due to the pneumatic configuration thereof, takes the exhaust conduit 103, to be discharged to the ambient atmosphere via the outlet port 103c of the exhaust conduit 103.

[0153] In the O2 50 supply facility of Fig. 1 , the intake duct 310 of the O 2 3 generation unit of Fig. 2 is connected to the extraction duct 108 of the exhaled gas purification unit 1 of Fig. 3 , via the first interconnection conduit 31, in order to be able to supply the O 2 3 generation unit, in particular the first internal gas line 3100 with air coming from the exhaled gas purification unit 1.

[0154] Within the exhaled gas purification unit 1, the control of the circulation of air within the internal air circuit 500 going from the intake duct 102 to the extraction duct 108 is carried out as follows, taking the example of a transit via the first adsorber 130, knowing that a similar control is carried out when the air passes through the other adsorbers.

[0155] The fourth rotary valve 140 is controlled by the piloting means 150, 151, to make a fluid connection between the downstream portion of the first conduit 120, i.e. downstream of the first downstream port 130b of the first cartridge 130, and the extraction conduit 108, while the first rotary valve 110 is controlled by the piloting means 150, 151, to make a fluid connection between the intake conduit 102 and the first conduit 120. There is then a fluid communication between the intake conduit 102 and the extraction conduit 108 via the first conduit 120 and first cartridge 130 respectively, allowing air to circulate from the intake conduit 102 to the extraction conduit 108 thanks to the suction force operated by the gas suction means 311, such as a fan or the like, arranged in the first internal gas line 3100. from the expired gas purification unit 1.

[0156] Indeed, since the intake duct 102 is connected to the ambient air via its port 102c, it can then be considered that the gas suction means 311, such as a fan, arranged in the intake duct 310 of the O23 generation unit can suck in ambient air through the port 102c, and that this sucked air then passes, respectively, through the intake duct 102, the first duct 120 on which the first cartridge 130 is arranged and the extraction duct 108 of the exhaled gas purification unit 1, to then be conveyed by the first interconnection duct 31 to the intake duct 31 of the O23 generation unit.

[0157] In other words, the O 2 3 generation unit is supplied with air by the interconnection conduit 31 which is fluidically connected to the intake conduit 310 by one of its ends, and to the conduit 108, by its other end, itself connected to the intake conduit 102 in communication with the atmosphere via the orifice 102c.

[0158] The flow of sucked air being at ambient temperature, typically between 15 and 30°C, it will cool the first adsorber 130 by passing through it, in particular the adsorbent which is there, knowing that it has been previously heated by the hot waste gas having been used for the regeneration of this adsorber 130 during a previous regeneration step.

[0159] Thus, the O23 generation unit is advantageously used to suck in air used to cool the first cartridge or adsorber 130, to allow its adsorbent to return to ambient temperature before being reused to capture the CO2 and the water vapor contained in the exhaled gases, during a subsequent purification phase.

[0160] It is understood that the exhaled gas purification unit 1 is controlled cyclically in order to continuously ensure its function of purifying exhaled gases while ensuring the regeneration and temperature reconditioning, i.e. cooling, of the adsorption cartridges 130-132.

[0161] In the example above, when the first cartridge 130 is saturated, the second cartridge 131 becomes the active cartridge for purifying the exhaled gases, while the first cartridge 130 begins its regeneration phase. Then, when the second cartridge 131 becomes saturated, the third cartridge 132 becomes the active cartridge and the second cartridge 131 begins a regeneration phase while the first cartridge 130 begins a cooling phase. When the third cartridge 132 becomes saturated, the first cartridge 130 then becomes the active cartridge again, while the third cartridge begins a regeneration phase and the second cartridge 131 begins a cooling phase.

[0162] Such a sequence is repeated cyclically during the operation of the installation 50.

[0163] Depending on the operating conditions and parameters and the architecture of the installation 50, such as the sizing of the cartridges, nature of the adsorbents, regeneration temperature, etc., the respective durations or times to reach saturation, complete regeneration and cooling to ambient temperature of the different adsorption cartridges may be equivalent or equal, or different.

[0164] Depending on the disparities observed between the different saturation, regeneration and cooling times, an additional number of cartridges, associated with their own rotary valves, connected via additional sub-ducts to the ducts described above can be integrated into the exhaled gas purification unit 1. For example, if the time to regenerate and cool a cartridge is twice the time required at its saturation limit, the exhaled gas purification unit 1 can integrate 5 cartridges in order to double the regeneration and cooling times once a cartridge has reached saturation.

[0165] The respiratory gas supply installation 50 of the invention is suitable for administering gas to a patient in a hypoxemic state, in particular a person in a hypoxemic state infected by a coronavirus, such as Covid-19 or the like, whether an adult, in particular an elderly person, an adolescent or a child.

[0166] Such a gas supply installation 50 constitutes an oxygen supply assembly implementing an “on-site” source of gaseous oxygen for delivering a supply flow rich in gaseous oxygen, such as pure or almost pure oxygen (i.e. 99.5% to 100% vol.), on the one hand, and an exhaled gas purification system, on the other hand, to recover the oxygen, normally lost, which is present in the gases exhaled by the patient (in a mixture with CO 2 ), then recycle it into the oxygen-rich supply flow, and thus ensure delivery of oxygen at a high concentration of O 2 (>95 to 99% vol.) to a user, typically a patient.

[0167] This makes it possible to limit the overall consumption of O 2 while ensuring the supply of a high concentration of O 2 . In other words, thanks to the gas supply installation of the invention, it is possible to ensure an FiO 2 greater than 90% in the patient without resorting to a high flow rate of oxygen from the oxygen source given that a non-negligible proportion of the flow of oxygen supplied to the patient consists of oxygen having been purified within the gas purification system and then recycled into the main gas delivery line, via the gas recycling line. Reusing a portion of the oxygen normally released into the atmosphere makes it possible to reduce the overall consumption of oxygen and therefore to greatly limit the stress on the O 2 reserves available on the site in question, i.e. hospital or other, by limiting oxygen losses.

[0168] Furthermore, using one or more electrochemical separation modules 316 with a ceramic membrane, preferably doped, has the advantage of providing very high purity oxygen, a necessary condition to allow the gas supply installation of the present invention to recycle the gases exhaled by the patient.

Claims

1. Installation (50) for supplying respiratory gas to a user (P), comprising: - a gas source (3) for supplying an oxygen-containing respiratory gas, - a main gas delivery line (23) fluidically connecting the gas source (3) to a respiratory interface (21) configured to administer the oxygen-containing respiratory gas to the user, during each inspiratory phase of said user, - a gas recovery line (10) configured to recover and convey at least some of the CO2 / O2 gas mixture exhaled by the user and located in the respiratory interface, during each expiratory phase of the user, said gas recovery line (10) fluidically connecting the respiratory interface (21) to a gas purification system (1) comprising adsorbers (130-132) arranged in parallel and each containing at least one adsorbent, said gas recovery line (10) supplying said gas purification system (1) with said CO2 / O2 gas mixture exhaled by the user, and - a gas recycling line (11) fluidically connecting the gas purification system (1) to the main gas delivery line (23), characterized in that the gas source (3) comprises an oxygen generation unit (30) comprising: - at least one electrochemical separation module (316), - a first gas line (3100) for supplying said at least one electrochemical separation module (316) with air, - gas heating means (313) arranged on the first internal gas line (3100), upstream of said at least one electrochemical separation module (316), and - a second gas line (3200) fluidically connecting said at least one electrochemical separation module (316) to the gas purification system (1), for conveying a flow of waste gas to the gas purification system (1) in order to regenerate said at least one adsorbent contained in at least one of said adsorbers (130-132).

2. Installation according to Claim 1, characterized in that the gas purification system (1) comprises at least three adsorbers (130-132) arranged in parallel.

3. Installation according to Claim 1, characterized in that the main gas delivery line (23) comprises a buffer tank (24), and the gas recycling line (11) is fluidically connected to the buffer tank (24).

4. Installation according to Claim 1, characterized in that the gas purification system (1) is fluidically connected to the first gas line (3100) of the oxygen generation unit (30) in order to supply air to said first gas line (3100), preferably via a first interconnecting duct (31).

5. Installation according to Claim 4, characterized in that the gas purification system (1) comprises an air circuit (500) for conveying air supplied to the first gas line (3100) of the oxygen generation unit (30).

6. Installation according to Claim 5, characterized in that the air circuit (500) comprises air passages or ducts (102, 108, 120-122), and at least one adsorber (130-132), preferably it further comprises at least one control valve (110-112; 140-142).

7. Installation according to Claim 1, characterized in that said at least one electrochemical separation module (316) of the oxygen generation unit (30) comprises one or more ceramic membranes.

8. Installation according to one of Claims 1, 4 and 5, characterized in that the first gas line (3100) of the oxygen generation unit (30) comprises gas suction means (311), said gas heating means (313) being arranged between the gas suction means (311) and said at least one electrochemical separation module (316).

9. Installation according to either of Claims 1 and 8, characterized in that heat exchange means (312) are arranged on the first internal gas line (3100), preferably between the gas suction means (311) and the gas heating means (313).

10. Installation according to Claim 1, characterized in that the second gas line (3200) conveys a waste gas having an oxygen concentration of less than 21 vol%, typically less than 20 vol%, and / or at a temperature of at least approximately 250°C, preferably at least approximately 300°C.

11. Installation according to Claims 1 and 9, characterized in that the second gas line (3200) is arranged in parallel with the first gas line (3100) within said heat exchange means (312) so as to carry out a heat exchange between the air flow circulating in the first gas line (3100) and the waste gas circulating in the second gas line (3200), preferably a counter-current heat exchange.

12. Installation according to either of Claims 1 and 6, characterized in that: - the O2 generation unit (30) comprises first control means (350, 351) configured to control said at least one electrochemical separation module (316), and / or - the gas purification system (1) comprises second control means (150, 151) for controlling at least some of the control valves (110-112; 140-142).

13. Installation according to Claim 1, characterized in that the respiratory interface (21) is a respiratory mask.

14. Installation according to Claim 1, characterized in that a second interconnecting duct (33) fluidically connects the second gas line (3200) of the O2 generation unit (30) to the gas purification system (1).

15. Installation according to Claim 1, characterized in that the gas purification system (1) further comprises: - a gas recycling circuit (502) for conveying at least the exhaled gas supplied by the gas recovery line (10), and - a regeneration circuit (501) for conveying at least the waste gas supplied by the oxygen generation unit (50), said gas recycling circuit (502) and regeneration circuit (501) comprising gas ducts and the adsorbers (130-132).