WO2024100331A1

WO2024100331A1 - Heat-engine vehicle equipped with an on-board co2 capture and conversion system

Info

Publication number: WO2024100331A1
Application number: PCT/FR2023/051545
Authority: WO
Inventors: Zlatina DIMITROVA; Gabriel Crehan
Original assignee: Stellantis Auto Sas
Priority date: 2022-11-10
Filing date: 2023-10-05
Publication date: 2024-05-16
Also published as: FR3141967A1

Abstract

The vehicle (VTH) is equipped with an on-board system for capturing and converting carbon dioxide (CO2) emitted in the exhaust gases of its heat engine (MT). According to the invention, the system comprises at least one compact and removable CO2 storage tank (RC), in which the captured CO2 is stored in the form of supercritical fluid, and a reversible fuel cell (PCR) and an electro-catalytic reactor (REC) which cooperate to produce a synthesis fuel from the captured CO2, the synthesis fuel being supplied to the heat engine to fuel the combustion.

Description

DESCRIPTION

TITLE OF THE INVENTION: THERMAL VEHICLE EQUIPPED WITH AN ON-BOARD CO2 CAPTURE AND CONVERSION SYSTEM

[0001] The present invention claims the priority of French application No. 2211716 filed on 10.11.2022, the content of which (text, drawings and claims) is here incorporated by reference.

[0002] The present invention generally relates to the reduction in the atmosphere of carbon dioxide (CO2) linked to human activities. More particularly, the invention relates to a thermal vehicle equipped with an on-board system for capturing and converting CO2 emitted in the exhaust gases. The invention also relates to a system for capturing and collecting CO2 in a fleet of these equipped thermal vehicles.

[0003] Several automobile manufacturers have announced ambitious voluntary commitment objectives, spanning between 2035 and 2050, with respect to the carbon neutrality of their activities and their vehicle fleets. Automobile manufacturers are thus participating in the necessary efforts aimed at limiting global warming to a maximum of 2°C by 2100, in accordance with the 2015 Paris agreements. [0004] Carbon neutrality is a concept that seems simple at first glance, but which in reality is very complex to implement, particularly in large industrial organizations with international activities, which is the case of the automobile industry. Carbon neutrality is achieved when the emissions balance is zero, that is to say, when CO2 emissions into the atmosphere generated by the company's activities are offset by other activities of the company. which remove CO2 from the atmosphere in equal quantities. This concept applies to the complete operation of the company, which covers the entire life cycle of its products, from their manufacturing to their recycling, the supplier network, the logistics chain, the home-work transport of its employees and many other aspects. Reducing CO2 emissions from various polluting processes implemented within the company is a first avenue to explore, which is immediately obvious. However, certain sectors of activity may face insurmountable obstacles, at least in the short and medium term, taking into account, for example, the state of scientific knowledge and available technology. Companies are then offered the possibility of resorting to compensatory measures such as participating in reforestation, recycling of raw materials, purchasing carbon credits from organizations carrying out concrete actions contributing to the reduction of greenhouse gases. greenhouse, and others.

[0005] For automobile manufacturers, the reduction of CO2 emissions from the exhaust gases of thermal engines is a priority objective, taking into account the importance of the global automobile fleet, a fleet which should reach a peak in 2039 according to the forecasts from the Bloomberg New Energy Finance (BNEF) institute. THE improvements made to gasoline and diesel thermal engines, to improve their efficiency and reduce emissions, as well as the electrification of vehicles, via hybridization and all-electric, are already leading to considerable reductions in CO2 emissions by new generation vehicles. Furthermore, improvements made to the engines of new generation vehicles allow manufacturers to comply, in the short and medium term, with restrictive and evolving regulations on pollutant emissions.

[0006] However, although the technical advances made over the last decade towards green mobility, respectful of the climate and the environment, are encouraging, there is still a lot of progress to be made in the automobile industry to achieve carbon neutrality.

[0007] In the state of the art, devices on board thermal vehicles are known to capture and store the CO2 emitted by the thermal engine. Other devices are also known to convert the CO2 emitted by the heat engine into a synthetic fuel.

[0008] Thus, from document EP2472077A1, a system is known for capturing CO2 in the exhaust gases of a heat engine and storing it in liquid form in a storage tank integrated into a vehicle. The storage tank is designed to be emptied by means of a CO2 recovery facility which is located, for example, at a refueling service station. In addition to the storage tank, the on-board means include a purifier tank containing a fluid which absorbs the CO2 present in the exhaust gases. A compressor is also provided to liquefy the CO2 for storage. The capacity of the storage tank is sized sufficient to obtain a frequency of emptying the CO2 which is of the same order as the frequency of refueling the vehicle. The driver of the vehicle can thus fill up with fuel and empty the CO2 storage tank during the same trip to the refueling service station.

[0009] Document US20170306825A1 describes a device for capturing and converting the CO2 emitted by a heat engine into a synthetic fuel. The device includes a CO2 gas capture material and a methanization catalyst. In the catalyst, CO2 molecules desorbed by the capture material react with hydrogen H2 molecules to generate methane. Hydrogen is supplied by a power source. The capture device controls an increase in the temperature of the capture material, using the heat generated by the heat engine, so as to cause the desorption of the CO2.

[0010] Document JP2010235736A describes a system for producing synthetic fuel from captured CO2. A CO2 absorption material allows it to be captured. The thermal energy used to cause the desorption of CO2 is also used to cause the fuel synthesis reaction.

[0011] It is desirable to propose a new design of a thermal vehicle equipped with an on-board system for capturing and converting the CO2 emitted in the exhaust gases, as well as a CO2 capture and collection system adapted to a fleet of these vehicles, in order to help the automobile industry achieve carbon neutrality.

[0012] According to a first aspect, the invention relates to a vehicle equipped with a thermal engine and an on-board system for capturing and converting carbon dioxide (CO2) emitted in the exhaust gases of the engine. According to the invention, the on-board system comprises at least one compact and removable CO2 storage tank, in which the captured CO2 is stored in the form of supercritical fluid, and a reversible fuel cell and an electro-catalytic reactor which cooperate to produce a synthetic fuel from the captured CO2, the synthetic fuel being supplied to the heat engine to power the combustion. [0013] According to a particular characteristic, the on-board system also comprises a device for capturing the water present in the exhaust gases of the heat engine, the captured water supplying the reversible fuel cell for production of hydrogen and oxygen in an electrolyzer operating mode thereof, and the hydrogen and oxygen produced being supplied to the electro-catalytic reactor, together with the captured CO2, for the production of the synthetic fuel. [0014] According to another particular characteristic, excess quantities of hydrogen and oxygen produced are supplied to the heat engine to power combustion, via an exhaust gas recirculation valve called "EGR" (for "Exhaust Gas"). Recirculation” in English) of it.

[0015] According to yet another particular characteristic, an excess quantity of the hydrogen produced is reinjected into the reversible fuel cell for regeneration of its electrodes.

[0016] According to yet another particular characteristic, an excess quantity of the hydrogen produced is supplied to the reversible fuel cell for production of electricity in a hydrogen fuel cell operating mode thereof.

[0017] According to yet another particular characteristic, the electro-catalytic reactor is a Sabatier reactor producing methane gas, as a synthetic fuel, from the captured CO2, and hydrogen and oxygen produced by the battery reversible fuel.

[0018] According to yet another particular characteristic, methane gas is supplied to the heat engine to power combustion, via a so-called “EGR” valve. [0019] According to yet another particular characteristic, the on-board system also includes another storage tank dedicated to storing synthetic fuel.

[0020] According to yet another particular characteristic, the on-board system also includes an organic cycle machine, called a “Rankine machine”, and a photovoltaic solar panel, the organic cycle machine producing electricity and energy in cogeneration. hot water from the waste heat of gases exhaust and the photovoltaic solar panel producing renewable electricity, the electricity produced being used to charge an electrical energy store of the vehicle and the hot water produced being used for heating the vehicle.

[0021] The invention also relates to a CO2 capture and collection system in a rolling automobile fleet comprising a plurality of vehicles as briefly described above and a collection station comprising storage, management and monitoring means CO2 storage tanks for vehicles and means of managing user accounts associated with the vehicles.

[0022] Other advantages and characteristics of the present invention will appear more clearly on reading the detailed description below of a particular embodiment of the invention, with reference to the single appended drawing, in which:

[0023] [Fig.1] Figure 1 is a general block diagram illustrating a particular embodiment of the present invention.

[0024] With reference to Figure 1, a particular embodiment of a VTH thermal vehicle according to the invention is now described, as well as an example of an SCC system for capturing and collecting CO2 in a rolling vehicle fleet comprising a plurality of these VTH thermal vehicles.

[0025] Generally speaking, the VTH thermal vehicle according to the invention comprises an on-board system which captures the gaseous CO2 present in the burnt gases of the MT thermal engine of the vehicle, stores part of the CO2 captured in a compact and removable tank in a supercritical fluid state and converts another part into a synthetic fuel. The synthetic fuel is stored in another tank to be used for combustion in the heat engine. Products derived from the processes implemented, in the form of excess hydrogen and oxygen, are also used in the combustion of the thermal engine or to produce electricity. An organic Rankine cycle machine, called an “ORC” machine for “Organic Rankine Cycle” in English, can also be integrated into the on-board system for cogeneration of electricity and useful heat, as well as a photovoltaic solar panel, so as to improve the energy balance of the VTH thermal vehicle according to the invention.

[0026] As shown schematically in Figure 1, the CO2 capture and conversion system on board the VTH thermal vehicle comprises in particular a DT device for CO2 capture and treatment and a DC device for CO2 conversion.

The CO2 capture and treatment device, DT, essentially comprises a CO2 capture device CT, a CD condensation device and an RC CO2 storage tank.

The CO2 capture device CT is connected bidirectionally to an exhaust gas bypass device DR which is installed in the LE exhaust line of the vehicle, downstream of a three-way catalyst CAT thereof. . The exhaust gases are directed by the DR bypass device to the CT device for CO2 capture by filtration, and then return to the DR bypass device for evacuation via the LE exhaust line. The CT capture device captures the CO2 in the burnt gases coming from the combustion chamber of the MT thermal engine, burnt gases which have been cleaned of HC, CO and Nox by the CAT catalyst, in accordance with current emissions standards. The CT capture device is formed of a CO2 filter, or CO2 trap, and typically comprises a separation membrane ensuring separation of CO2 and inorganic oxides. This membrane is rigid and is covered with a layer of porous ceramic as an outer layer. The CT collection device is designed to withstand the high temperature of the exhaust gas, between 300°C and 950°C. Preferably, the shape of the CT collection device is tubular or rectangular, which facilitates its installation in the LE exhaust line.

The function of the condensation device CD is to condense the gaseous CO2 recovered by the capture device CT into the form of a supercritical fluid. The CD condensing device essentially comprises an ET heat exchanger and a PT compressor. The ET heat exchanger and the PT compressor bring the CO2 to the required temperature and pressure conditions to obtain the condensation of the CO2 in the state of supercritical fluid. The ET heat exchanger is passed through by the gaseous CO2 and is connected to the EC hot water heating and air conditioning circuits of the VTH vehicle. In the ET exchanger, the temperature of the gaseous CO2 is controlled through thermal exchanges of the gaseous CO2 with the hot water and the air conditioning heat transfer fluid of the EC circuits. The temperature of the gaseous CO2 is thus maintained at a temperature above 31°C which will allow a transition to the supercritical fluid state.

The PT compressor is supplied with electricity by an EL electrical supply network of the VTH vehicle. The PT compressor receives as input the gaseous CO2 conditioned by the ET exchanger at the appropriate temperature, above 31°C, and compresses it to cause its condensation to the state of supercritical fluid. At the outlet of the PT compressor, the CO2 in the state of supercritical fluid is brought to the RC storage tank to fill it. It will be noted that the function of the PT compressor may in certain embodiments of the invention be provided by the air conditioning compressor of the VTH vehicle operating on a time-shared basis.

The condensation of CO2 in the state of supercritical fluid causes an increase in its density, which allows the storage of a greater quantity of CO2 in a given volume. The RC storage tank can thus be produced in a more compact form. In the present invention, the RC storage tank is a removable tank which, once full, must be removed from the vehicle and replaced with an empty tank. As visible in Figure 1, the RC storage tank is equipped with a DH filling detector which controls the activation on the vehicle dashboard of a full tank indicator for the driver. The capacity of the RC tank, typically between approximately 10 and 20 liters, is a standard capacity which is sized to obtain a tank change frequency which is of the same order as the frequency of refueling of the vehicle. The driver of the vehicle can thus fill up with fuel and change his RC tank during the same trip to a refueling service station.

The CO2 conversion device, DC, essentially comprises a water capture device CE, a reversible fuel cell PCR, an electro-catalytic reactor REC and an RF synthesis fuel storage tank.

The CE water capture device is a water trap (H2O) which supplies water in the liquid state from the water vapor present in the exhaust gases of the MT heat engine. The CE water capture device is connected bidirectionally to the DR exhaust gas bypass device. The exhaust gases are directed by the DR bypass device to the CE device for water capture, and then return to the DR bypass device for evacuation via the LE exhaust line.

The reversible PCR fuel cell has two operating modes, namely, a first mode in which it operates as an electrolyzer and a second mode in which it operates as a hydrogen fuel cell.

[0035] In the electrolyzer mode, the PCR battery consumes water (H2O) supplied by the water trap CE and electrical energy supplied by the electrical supply network EL and produces hydrogen (H2) and oxygen (02). The hydrogen (H2) and oxygen (02) produced are used by the electro-catalytic reactor REC, together with CO2 from the storage tank RC, to produce synthetic fuel, namely here, methane (CH4 ). The excess hydrogen (H2) and oxygen (02) are supplied to the MT thermal engine, via a V_EGR valve of the “EGR” type for “Exhaust Gas Recirculation” in English, to improve the combustion of the MT thermal engine. and, correlatively, its performance. The excess hydrogen (H2) is also used for the regeneration of the cell, by cleaning its electrodes, as well as for the production of electricity in the hydrogen fuel cell mode.

[0036] In the hydrogen fuel cell mode, the PCR cell consumes the aforementioned excess hydrogen (H2), oxygen (02) from the air and produces electricity and water (H2O). The electricity produced contributes to recharging a high-voltage electrical energy store STK, typically of the Lithuim-ion (Li-ion) type, via means of electrical conversion and CH recharging.

The REC electro-catalytic reactor here is of the Sabatier reactor type. The REC reactor consumes hydrogen (H2) and oxygen (02) produced by the PCR stack in electrolyzer mode, as well as CO2 coming from the RC storage tank and electrical energy supplied by the electricity network. EL power supply, and produces methane gas (CH4) as a synthetic fuel. Electricity provided to the REC reactor allows it to be heated to the appropriate temperature for the catalytic reaction, by means of an electrical heating resistance included in the REC reactor. The methane (CH4) produced by the REC electro-catalytic reactor is stored in an RF synthesis fuel storage tank.

The methane (CH4) produced is supplied to the MT heat engine for combustion, via the aforementioned V_EGR valve. The methane gas (CH4) directed to the V_EGR valve comes directly from the REC electro-catalytic reactor or the RF storage tank. The V_EGR valve is controlled using measurement information provided by Lambda probes LB1 and LB2 placed at the inlet and outlet of the engine combustion chamber. The Lambda LB1 probe is typically positioned directly downstream of the V_EGR valve. The Lambda LB2 probe is typically positioned in the gas recirculation loop. The V_EGR valve, controlled from the Lambda probes LB1 and LB2, allows optimal dosing of the recirculation of exhaust gases, as well as hydrogen (H2), oxygen (02) and methane (CH4) provided by the DC CO2 conversion device, to the AIR air intake loop of the MT heat engine.

[0039] As also visible in Figure 1, the CO2 capture and conversion system also includes an organic cycle machine MR and a photovoltaic solar panel PS.

The organic cycle machine MR is a Rankine machine comprising a heat exchanger EH, called “hot”, a heat exchanger EF, called “cold”, an electric pump PO and a turbo-alternator TA. The heat exchangers EH, EF, the PO pump and the TA turbo-alternator are integrated into a phase change heat transfer fluid circuit (liquid/gas). The phase changes of the heat transfer fluid are generated by the temperature difference existing between the heat exchangers EH, EF. The heat transfer fluid is heated in the heat exchanger EH crossed by the exhaust gases of the heat engine MT. The heat transfer fluid is cooled in the EF heat exchanger integrated into an EC hot water heating circuit. The work generated in the MR machine is converted into electricity by the TA turbo-alternator, which is driven in rotation by the mechanical torque exerted on its turbine by the heat transfer fluid in the gas phase. The electricity produced contributes to recharging the high-voltage electrical energy store STK, via the means of electrical conversion and CH recharge. The calories extracted from the EF heat exchanger heat the water in the EC heating circuit, thus contributing to the comfort of the people present in the VTH vehicle.

[0041] The photovoltaic solar panel PS is typically arranged on the roof of the vehicle and produces electricity which also contributes to recharging the high voltage electrical energy store STK, via the means of electrical conversion and recharging CH.

[0042] The organic cycle machine MR and the photovoltaic solar panel PS contribute to better recharging of the high voltage electrical energy store STK, from waste heat from exhaust gases and renewable solar energy. A PG electrical charging socket is also provided in the VTH vehicle to complete the recharging of the high voltage electrical energy store STK, preferably from an electrical charging station providing renewable electrical energy.

The CO2 storage tank, RC, is a removable tank which, once full, must be removed from the VTH vehicle and replaced by an empty tank. In certain embodiments, the synthetic fuel storage tank will also be a removable tank replaceable by an empty tank. Advantageously, the RC tank is of a standard interchangeable type. When full, the RC tank has a weight compatible with handling directly by the user for replacement.

As shown schematically in Figure 1, the SCC system according to the invention comprises an SCR station for collecting and replacing full RC tanks. The SCR station includes means for storing, managing and monitoring storage tanks and means for managing user accounts associated with said vehicles.

[0045] Thus, in this exemplary embodiment, the SCR station is present on the site of an SRC service station for refueling and recharging an electric vehicle. The SCR station is in the form of a double automated DRA rack, self-service storage, which is controlled by a local BGI computerized control and management terminal including a MOD management software module with which the user can interact, for example via a dedicated software application on their smartphone or via human-machine interface means (screen, keyboard and others) of the terminal.

[0046] VTH vehicles arriving at the SCR station are identified automatically, for example, from a license plate image taken by a CM camera. Once the VTH vehicle has been identified, the BGI terminal calculator interacts with a remote IT server SID hosting DBs databases of registered users/vehicles and tank management and traceability. The tanks are identified individually, for example by a unique QR code. The QR code is scanned for traceability when removing a full tank and when removing an empty tank. Validation of a user/vehicle by consulting the remote computer server SID by the BGI terminal leads to sequential unlocking for the user of two sections SRP and SRV of the double automated DRA rack. The SRP section is for removing a full RC tank and is unlocked first. Then, once the full tank has been removed, the SRV section containing empty RC replacement tanks is unlocked and the user can remove an empty RC tank and install it in their HTV vehicle.

[0047] Users are rewarded for their eco-responsible behavior. Each deposit of a full tank by a user validates a credit on their user account, for example, for a reduction on a fuel purchase or on the price of electrically recharging your vehicle.

[0048] The filling level of the tank deposited by a user can be controlled and guaranteed by different means. Thus, removal of the tank from the vehicle may only be authorized when the filling detector (DH) of the vehicle indicates that the tank is full. In addition, the tank deposited in the SRP deposit section can also be weighed on a scale in the automated double rack before being accepted.

[0049] The CO2 coming from the reservoirs can be treated by different FT channels represented schematically in Figure 1. The conversion of CO2 from reservoirs into synthetic fuel can be done on a large scale by synthetic fuel production plants. CO2 can also be used in aquaculture, for example, for the growth of edible algae or microalgae used in the composition of high value-added products. CO2, reduced to carbon powder, can also be sequestered in the ground by burial. In addition to the examples above, several other sectors of CO2 use, with or without transformation, are known such as carbon dioxide for carbonated drinks, dry ice, refrigerating liquids, urea in the fertilizer industry , polycarbonates and others.

The invention is not limited to the particular embodiment which has been described here by way of example. A person skilled in the art, depending on the applications of the invention, may make different modifications and variants falling within the scope of protection of the invention.

Claims

[Claim 1] Vehicle (VTH) equipped with a thermal engine (MT) and an on-board system for capturing and converting carbon dioxide (CO2) emitted in the exhaust gases of said engine (MT), characterized in that said on-board system comprises at least one CO2 storage tank (RC), compact and removable, in which the captured CO2 is stored in the form of supercritical fluid, and in that said on-board system also comprises a fuel cell reversible (PCR) and an electro-catalytic reactor (REC) which cooperate to produce a synthetic fuel from the captured CO2, said synthetic fuel being supplied to said thermal engine (MT) to power the combustion.

[Claim 2] Vehicle according to claim 1, characterized in that said on-board system also comprises a device (CE) for capturing the water present in the exhaust gases of said thermal engine (MT), the captured water supplying said reversible fuel cell (PCR) for producing hydrogen and oxygen in an electrolyzer mode of operation thereof (PCR), and the hydrogen and oxygen produced being supplied to said electro-catalytic reactor (REC ), together with the captured CO2, for the production of said synthetic fuel.

[Claim 3] Vehicle according to claim 2, characterized in that excess quantities of hydrogen and oxygen produced are supplied to said heat engine (MT) to power combustion, via a so-called “EGR” valve (V_EGR) of this one.

[Claim 4] Vehicle according to claim 2 or 3, characterized in that an excess quantity of the hydrogen produced is reinjected into said reversible fuel cell (PCR) for regeneration of the electrodes thereof.

[Claim 5] Vehicle according to claim 2 or 3, characterized in that an excess quantity of the hydrogen produced is supplied to said reversible fuel cell (PCR) for electricity production in a fuel cell operating mode. hydrogen fuel thereof (PCR).

[Claim 6] Vehicle according to any one of claims 2 to 5, characterized in that said electro-catalytic reactor (REC) is a Sabatier reactor producing methane gas, as said synthetic fuel, from CO2 captured, and hydrogen and oxygen produced by said reversible fuel cell (PCR).

[Claim 7] Vehicle according to claim 6, characterized in that said methane gas is supplied to said heat engine (MT) to power combustion, via a so-called “EGR” valve (V_EGR) thereof.

[Claim 8] Vehicle according to any one of claims 1 to 7, characterized in that said on-board system also comprises another storage tank (RF) dedicated to storage of said synthetic fuel.

[Claim 9] Vehicle according to any one of claims 1 to 8, characterized in that said on-board system also comprises an organic cycle machine (MR), called a “Rankine machine”, and a photovoltaic solar panel (PS), said organic cycle machine (MR) producing electricity and hot water in cogeneration from the waste heat of exhaust gases and said photovoltaic solar panel (PS) producing renewable electricity, electricity produced being used to charge an electrical energy store (STK) of the vehicle (VTH) and the hot water produced being used for heating (EC) of the vehicle (VTH).

[Claim 10] System (SCC) for capturing and collecting carbon dioxide (CO2) in a rolling automobile fleet, characterized in that it comprises a plurality of vehicles (VTH) according to any one of claims 1 to 9 and a collection station (SCR) comprising means (DRA, BGI, SDI, DBs) for storage, management and monitoring of the CO2 storage tanks (RC) of said vehicles (VTH) and means (BGI, SDI, DBs) for managing user accounts associated with said vehicles (VTH).