Heat management method in a combined process involving methanol production

Abstract

The present disclosure relates to a heat management method in a methanol-generating unit remarkable in the reactor (100) of the methanol-generating unit comprises a cooling device and wherein the steam (5, 7) recovered from said cooling device has a pressure that is suitable for being fed into the one or more solid oxide electrolyser cells (400), so as to provide a hydrogen-rich effluent (15) that is used to enhance the efficacy of the separation unit necessary for the methanol production.

Description

[0001] Heat management method in a combined process involving methanol production

[0002] Field of the disclosure

[0003] The present disclosure relates to a heat management method in a combined process involving methanol production and also optionally hydrogen production.

[0004] Technical background

[0005] Methanol is widely used in different applications such as the synthesis of formaldehyde, which is then involved in the manufacture of plastic materials, paints, and textiles, for instance; the production of dimethyl ether, which may be used in aerosols or as an alternative fuel for diesel engines; the transesterification of triglycerides to produce biodiesel; or as a solvent or a fuel for engines.

[0006] Methanol is commercially produced from synthesis gas (syngas), namely a mixture of carbon oxides ( / .e., carbon monoxide (CO) and / or carbon dioxide (CO2)) and hydrogen (H2) that can be produced from a variety of carbonated sources.

[0007] CO and CO2 react with H2 according to the following equations:

[0008] (1) CO + 2H2CH3OH

[0009] (2) CO2+ 3H2CH3OH + H2O

[0010] (3) CO + H2O CO2+ H2wherein the third one corresponds to the water-gas shift (WGS) reaction.

[0011] When methanol is produced by a process involving the production of hydrogen by water electrolysis, using green electricity, over an alkaline electrolyser and its use to convert CO2 in a CO2-to-methanol unit, the CO2-to-methanol pathway consumes 12.3 kWh / kgMeon.

[0012] This amount of energy spent on the generation of methanol can be considered as an impediment, since the current trends are rather focusing on processes that are ecological and / or energy-saving, with the ultimate goal of preserving the environment.

[0013] Such an approach implementing green policies has already been executed at some point. For example, the feeding of hydrogen and / or syngas using solid oxide electrolyser cells has succeeded in decreasing the amount of energy needed to perform the required reaction. A solid oxide electrolyser cell allows indeed to achieve the electrolysis of steam (SOEC) or the co-electrolysis of steam and CO2 (co-SOEC) by using a solid oxide electrolyte to produce hydrogen gas or syngas respectively. The use of a high-temperature electrolyser allows using more heat energy than electrical energy. The energy is partially recovered on the SOEC / co- SOEC, as in US 2018 / 0287179, to pre-heat the steam from 125°C-180°C to the electrolysis temperature. The fact of being able to produce steam on the combined process leads reducing the heat energy to provide to the electrolyser and the distillation unit, increasing, therefore, the overall energy efficiency of the process. The solid oxide electrolyser cells usually operates at temperatures that allow high-temperature electrolysis to occur, typically between 500°C and 865°C. Thus, when combined with the water electrolysis, the CCh-to-methanol pathway consumes 11.59 kWh / kgMeon and when combined with co-electrolysis of CO2, the CCh-to- methanol pathway is consuming 10.48 kWh / kgMeOH.

[0014] However, there is still a need to reduce the energy consumption of a combined process involving methanol production in order to implement the ongoing green environmental policies. More particularly, there is a need to reduce the energy consumption of a combined process involving methanol production and hydrogen production in order to implement the ongoing green environmental policies.

[0015] Summary

[0016] According to a first aspect, the disclosure provides a heat management method in a methanolgenerating unit, said method is remarkable in that it comprises the following steps: a) providing a methanol-generating unit and a separation unit, wherein the separation unit is placed downstream of the methanol-generating unit and is in fluidic connection with it, wherein said separation unit comprise a temperatureregulating device, and wherein said methanol-generating unit comprises one or more reactors each comprising a cooling device; b) operating said at least one reactor under first operating conditions comprising at least regulating the thermal energy of said at least one reactor by adjusting the temperature of the cooling device with water; c) recovering from said cooling device, after said step of regulating the thermal energy, a first stream, said first stream comprising steam at a pressure P1; d) decreasing the pressure of said first stream so as to recover a second stream, said second stream comprising steam at a pressure P2, wherein P2 < P1 ; e) providing one or more solid oxide electrolyser cells; f) feeding said one or more solid oxide electrolyser cells with at least the second stream recovered at step (d) or with a mixture comprising carbon dioxide and at least the second stream recovered at step (d); g) working said one or more solid oxide electrolyser cells under second operating conditions so as to generate a hydrogen-rich effluent or a syngas effluent, said second operating conditions comprising at least electrical power and a temperature higher than 400°C; wherein the first operating conditions of step (b) comprise feeding said at least one reactor with either a carbon oxides feedstock and the hydrogen-rich effluent generated at step (g) or the syngas effluent generated at step (g).

[0017] Surprisingly, it has been found that a cooling system attributed to a methanol-generating unit allows the production of steam with a pressure suitable to be fed into said one or more solid oxide electrolyser cells, and subsequently reducing the overall energy consumption of a process producing methanol, and optionally hydrogen or syngas, when reinjecting the hydrogen-rich effluent or the syngas effluent into the reactor of the methanol-generating unit.

[0018] STEP (b)

[0019] For example, the first operating conditions of step (b) comprise providing a carbon oxides feedstock to said at least one reactor, providing a stream of hydrogen and mixing together the carbon oxides feedstock and the stream of hydrogen within said at least one reactor so as to produce a methanol effluent.

[0020] For example, the water used in step (b) for adjusting the temperature of the cooling device has a pressure ranging between 1.5 MPa and 12.0 MPa, or between 2.2 MPa and 7.0 MPa.

[0021] For example, the water used in step (b) for adjusting the temperature of the cooling device has a temperature ranging between 100°C and 200°C, or between 120°C and 150°C.

[0022] For example, the step (b) of operating said at least one reactor generates a reactor effluent, and the method further comprises the step of providing a water stream and the step of transferring the thermal energy of said reactor effluent to said water stream so as to generate a third additional stream of steam, said third additional stream of steam being then fed to said one or more solid oxide electrolyser cells. With preference, the water stream provided to generate said third additional stream of steam is at a pressure ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa (i.e., said water stream is a medium-pressurized water stream).

[0023] STEP (c)

[0024] For example, the first stream is at a temperature T 1 comprised between 200°C and 325°C, or between 200°C and 300°C, preferably between 205°C and 295°C, more preferably between 210°C and 290°C, even more preferably between 215°C and 285°C, most preferably between 220°C and 280°C, even most preferably between 220°C and 275°C.

[0025] For example, the pressure P1 of the first stream is comprised between 1.5 MPa and 12.0 MPa, preferably between 2.2 MPa and 7.0 MPa. The pressure P1 of the first stream is measured at dew point.

[0026] For example, the pressure P1 of the first stream corresponds to the pressure of the water used in step (b).

[0027] STEP (d)

[0028] The step (d) of decreasing the pressure of said first stream further produces electrical energy; and the method further comprises the step of supplying said electrical energy to said one or more solid oxide electrolyser cells so as to run said one or more solid oxide electrolyser cells.

[0029] The methanol-generating unit provided at step (a) comprises one or more compressors, and the step (d) of decreasing the pressure of said first stream further produces electrical energy and / or shaft work; and the method further comprises the step of supplying said electrical energy and / or shaft work to said one or more compressors so as to run the one or more compressors comprised within the methanol-generating unit.

[0030] For example, the pressure P2 of the second stream is ranging between 0.31 MPa and 1.30 MPa, preferably between 0.32 MPa and 1.29 MPa, preferably between 0.33 MPa and 1.28 MPa, more preferably between 0.34 MPa and 1.27 MPa, even more preferably between 0.35 MPa and 1.26 MPa, most preferably between 0.36 MPa and 1.25 MPa.

[0031] Advantageously, the second stream comprising steam at a pressure P2 further comprises one condensate; and the method further comprises the step of separating the steam from said condensate so as to recover a third stream, said third stream comprising steam at a pressure P3, wherein P3 is equal or inferior to P2.

[0032] With preference, the step (f) of feeding said one or more solid oxide electrolyser cells is a step of feeding said one or more solid oxide electrolyser cells with the third stream or with a mixture comprising carbon dioxide and the third stream.

[0033] For example, the pressure P3 of the third stream is ranging between 0.30 MPa and 1 .29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa.

[0034] Advantageously, the first operating conditions used in step (b) further comprise providing a carbon oxides feedstock to said at least one reactor, providing the hydrogen-rich effluent generated at step (g) as a stream of hydrogen within said at least one reactor, and mixing together the carbon oxides feedstock and the hydrogen-rich effluent within said at least one reactor so as to produce a methanol effluent.

[0035] Advantageously, the first operating conditions used in step (b) further comprise providing a carbon oxides feedstock to said at least one reactor by providing the syngas effluent generated at step (g) within said at least one reactor so as to produce a methanol effluent.

[0036] Advantageously, the method further comprises the step of increasing the pressure of the hydrogen-rich effluent or the syngas effluent before using it in the first operating conditions used at step (b).

[0037] Advantageously, the hydrogen-rich effluent or the syngas effluent is subjected to a pressure increase step before being directed to the reactor, said pressure increase step generating heat, and the method further comprises the step of providing a water stream and the step of transferring the heat generated by the pressure increase step to said water stream so as to generate a second additional stream of steam, said second additional stream of steam being then fed to said one or more solid oxide electrolyser cells. With preference, said water stream provided to generate said second additional stream is at a pressure ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa (i.e., said water stream is a medium-pressurized water stream).

[0038] Advantageously, the step (g) of working said one or more solid oxide electrolyser cells under second operating conditions also generates an oxygen-containing effluent and in that the method further comprises the following steps: h) providing a water stream; i) transferring the thermal energy of at least the oxygen-containing effluent to said water stream so as to produce an additional stream of steam; and j) transferring the thermal energy of the additional stream of steam to the temperatureregulating device of the separation unit.

[0039] For example, the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of a first part of said first additional stream of steam; and the method further comprises the step of feeding a second part of said additional stream of steam to said one or more solid oxide electrolyser cells during step (f).

[0040] For example, the method further comprises a step of transferring the thermal energy of either the hydrogen-rich effluent or the syngas effluent to the water stream before the step of transferring the thermal energy of at least the oxygen-containing effluent to said water stream so as to produce the additional stream of steam.

[0041] For example, said oxygen-containing effluent is at a temperature Toxeffluent ranging between 300°C and 400°C, preferably between 305°C and 395°C, more preferably between 310°C and 390°C.

[0042] Advantageously, the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream recovered at step (c).

[0043] For example, the step of transferring the thermal energy of said oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging between 0.30 MPa and 1.29 MPa and the additional stream of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa to 1.29 MPa by transferring the thermal energy of the oxygen outflow to said water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of the additional stream of steam at a pressure ranging between 0.30 MPa to 1.29 MPa to the temperature-regulating device of the separation unit.

[0044] For example, the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) and said step of transferring the thermal energy further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging between 0.30 MPa and 1.29 MPa and the additional stream of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa to 1.29 MPa by transferring the thermal energy of the oxygen outflow to said medium-pressurized water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of the additional stream of steam at a pressure ranging between 0.30 MPa to 1.29 MPa to the temperature-regulating device of the separation unit.

[0045] For example, the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) and said step of transferring the thermal energy further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging between 0.30 MPa and 1.29 MPa and the additional stream of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa to 1.29 MPa by transferring the thermal energy of the oxygen outflow to said water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of the additional stream of steam at a pressure ranging between 0.30 MPa to 1.29 MPa to the temperature-regulating device of the separation unit; and the hydrogen-rich effluent or the syngas effluent is subjected to a pressure increase step before being directed to the reactor, said pressure increase step generating heat, and the method further comprises the step of providing a water stream and the step of transferring the heat generated by the pressure increase step to said water stream so as to generate a second additional stream of steam, said second additional stream of steam being then fed to said one or more solid oxide electrolyser cells.

[0046] For example, the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) and said step of transferring the thermal energy further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging between 0.30 MPa and 1.29 MPa and the additional stream of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa to 1 .29 MPa by transferring the thermal energy of the oxygen outflow to said water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of the additional stream of steam at a pressure ranging between 0.30 MPa to 1.29 MPa to the temperature-regulating device of the separation unit; and the hydrogen-rich effluent or the syngas effluent is subjected to a pressure increase step before being directed to the reactor, said pressure increase step generating heat, and the method further comprises the step of providing a water stream and the step of transferring the heat generated by the pressure increase step to said water stream so as to generate a second additional stream of steam, said second additional stream of steam being then fed to said one or more solid oxide electrolyser cells; and the step (b) of operating said at least one reactor generates a reactor effluent, and the method further comprises the step of transferring the thermal energy of said reactor effluent to said water stream provided at step (h) so as to generate a third additional stream of steam, said third additional stream of steam being then fed to said one or more solid oxide electrolyser cells.

[0047] For example, said oxygen outflow is at a temperature Toxoutflow ranging between 260°C and 360°C, preferably between 265°C and 355°C, more preferably between 270°C and 350°C. For example, the additional stream of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa.

[0048] For example, the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of a first part of said additional stream of steam; and the method further comprises the step of feeding a second part of said additional stream of steam to said one or more solid oxide electrolyser cells during step (f).

[0049] For example, the method further comprises a step of transferring the thermal energy of either the hydrogen-rich effluent or the syngas effluent to the water stream before the step of transferring the thermal energy of the oxygen outflow to said water stream so as to produce the additional stream of steam at a pressure ranging between 0.30 MPa to 1 .29 MPa.

[0050] For example, when the step (f) of feeding said one or more solid oxide electrolyser cells is the step of feeding said one or more solid oxide electrolyser cells with the second stream recovered at step (d), the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is accompanied by a step of providing a complementary stream of steam at a pressure ranging between 0.30 MPa and 1 .29 MPa to the temperature-regulating device of the separation unit.

[0051] For example, the step of transferring the thermal energy of said oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging below 0.30 MPa and the additional stream of steam produced at step (i) is generated at a pressure below 0.30 MPa by transferring the thermal energy of the oxygen outflow to said water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperatureregulating device of the separation unit is the step of transferring the thermal energy of the additional stream of steam generated at a pressure below 0.30 MPa to the temperatureregulating device of the separation unit.

[0052] For example, the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) and said step of transferring the thermal energy further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging below 0.30 MPa and the additional stream of steam produced at step (i) is generated at a pressure below 0.30 MPa by transferring the thermal energy of the oxygen outflow to said water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is the step of transferring the thermal energy of the additional stream of steam generated at a pressure below 0.30 MPa to the temperature-regulating device of the separation unit.

[0053] For example, the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) and said step of transferring the thermal energy further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging below 0.30 MPa and the additional stream of steam produced at step (i) is generated at a pressure below 0.30 MPa by transferring the thermal energy of the oxygen outflow to said water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is the step of transferring the thermal energy of the additional stream of steam generated at a pressure below 0.30 MPa to the temperature-regulating device of the separation unit; and the hydrogen-rich effluent or the syngas effluent is subjected to a pressure increase step before being directed to the reactor, said pressure increase step generating heat, and the method further comprises the step of providing a water stream at a pressure ranging for example between 0.30 MPa and 1.29 MPa ( / .e., for example a medium-pressurized water steam) and the step of transferring the heat generated by the pressure increase step to said water stream ( / .e., to said medium-pressurized water steam) so as to generate a second additional stream of steam, said second additional stream of steam being then fed to said one or more solid oxide electrolyser cells.

[0054] For example, the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream recovered at step (c) and said step of transferring the thermal energy further generates an oxygen outflow; the water stream provided at step (h) is at a pressure ranging below 0.30 MPa and the additional stream of steam produced at step (i) is generated at a pressure below 0.30 MPa by transferring the thermal energy of the oxygen outflow to said water stream; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is the step of transferring the thermal energy of the additional stream of steam generated at a pressure below 0.30 MPa to the temperature-regulating device of the separation unit; and the hydrogen-rich effluent or the syngas effluent is subjected to a pressure increase step before being directed to the reactor, said pressure increase step generating heat, and the method further comprises the step of providing a water stream at a pressure ranging for example between 0.30 MPa and 1.29 MPa ( / .e., for example a medium-pressurized water steam) and the step of transferring the heat generated by the pressure increase step to said water stream ( / .e., to said medium-pressurized water steam) so as to generate a second additional stream of steam, said second additional stream of steam being then fed to said one or more solid oxide electrolyser cells, and the step (b) of operating said at least one reactor generates a reactor effluent, and the method further comprises the step of transferring the thermal energy of said reactor effluent to said water stream at a pressure ranging for example between 0.30 MPa and 1.29 MPa ( / .e., for example said medium-pressurized water steam) so as to generate a third additional stream of steam, said third additional stream of steam being fed to said one or more solid oxide electrolyser cells.

[0055] With preference, said step (j) is accompanied by a step of providing a backup stream of steam at a pressure below 0.30 MPa to the temperature-regulating device of the separation unit.

[0056] For example, the additional stream of steam produced at step (i) is generated at a pressure ranging between 0.10 MPa and 0.30 MPa, or between 0.11 MPa and 0.29 MPa, preferably between 0.12 MPa and 0.28 MPa, more preferably between 0.13 MPa and 0.27 MPa.

[0057] For example, the method further comprises a step of respectively transferring the thermal energy of the hydrogen-rich effluent or the syngas effluent to the water stream before the step of transferring the thermal energy of at least the oxygen-containing effluent to said water stream so as to respectively produce the additional stream of steam at a pressure below 0.30 MPa.

[0058] Advantageously, the method further comprises the step of providing a complementary stream of steam to said one or more solid oxide electrolyser cells, said complementary stream of steam being at a pressure ranging between 0.30 MPa and 1.29 MPa.

[0059] Advantageously, the method further comprises the step of providing a complementary stream of steam to said temperature-regulating device of the separation unit, said complementary stream of steam being at a pressure ranging between 0.30 MPa and 1.29 MPa.

[0060] According to a second aspect, the disclosure provides an installation for producing methanol remarkable in that the installation comprising a methanol-generating unit and a separation unit, wherein said separation unit is placed downstream of the methanol-generating unit and is in fluidic connection with it, wherein the separation unit comprises a temperatureregulating device, and wherein the methanol-generating unit comprising one or more reactors, each reactor comprising a cooling device; one or more solid oxide electrolyser cells, wherein said one or more solid oxide electrolyser cells are placed downstream of said cooling device, and in fluidic connection with it; each of said one or more solid oxide electrolyser cells comprising a hydrogen-output line to direct a hydrogen-rich effluent or a syngas effluent out of said solid oxide electrolyser cell; and wherein the installation further comprises a line fluidically connecting the hydrogenoutput line to the one or more reactors of the methanol-generating unit; at least one steam pressure-reducing device, the steam pressure-reducing device being placed downstream of said cooling device and upstream of said one or more solid oxide electrolyser cells; a first line connecting fluidically the cooling device to the one or more steam pressure-reducing devices; a second line connecting fluidically the one or more steam pressurereducing devices to the one or more solid oxide electrolyser cells, and wherein the one or more steam pressure-reducing devices comprise at least one steam pressure regulator.

[0061] With preference, the installation further comprises a hydrogen compression device located on the line fluidically connecting the hydrogen-output line to the one or more reactors of the methanol-generating unit.

[0062] Advantageously, the installation further comprises a gas-liquid separator, said gas-liquid separator being placed on the second line downstream of and in fluidic connection with said at least one steam pressure-reducing device, said gas-liquid separator comprising an overhead fluidically connected to the one or more solid oxide electrolyser cells.

[0063] Description of the figures

[0064] Figure 1a: Installation comprising a methanol-generating unit upstream of a separation unit along with a solid oxide electrolyser cell working in electrolysis mode (SOEC).

[0065] Figure 1 b: Installation comprising a methanol-generating unit upstream of a separation unit along with a solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC).

[0066] Figure 2a: Installation comprising a methanol-generating unit upstream of a separation unit. Steam at medium pressure ( / .e., above 0.30 MPa) is directed from a steam pressure-reducing device to the separation unit. A solid oxide electrolyser cell working in electrolysis mode (SOEC) is shown.

[0067] Figure 2b: Installation comprising a methanol-generating unit upstream of a separation unit. Steam at medium pressure ( / .e., above 0.30 MPa) is directed from a steam pressure-reducing device to the separation unit. A solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) is shown.

[0068] Figure 3a: Installation according to the present disclosure comprising a methanol-generating unit upstream of a separation unit. Steam at medium pressure ( / .e., above 0.30 MPa) is directed from a steam pressure-reducing device to the solid oxide electrolyser cell working in electrolysis mode (SOEC).

[0069] Figure 3b: Installation according to the present disclosure comprising a methanol-generating unit upstream of a separation unit. Steam at medium pressure ( / .e., above 0.30 MPa) is directed from a steam pressure-reducing device to the solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC).

[0070] Figure 4a: Installation according to the present disclosure wherein the oxygen-containing effluent exiting the solid oxide electrolyser cell working in electrolysis mode (SOEC) is further used to produce steam to improve the efficacy of the separation unit.

[0071] Figure 4b: Installation according to the present disclosure wherein the oxygen-containing effluent exiting the solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) is further used to produce steam to improve the efficacy of the separation unit.

[0072] Figure 5a: Installation according to the present disclosure wherein the oxygen-containing effluent and the hydrogen-rich effluent exiting the solid oxide electrolyser cell working in electrolysis mode (SOEC) are both further used to produce steam to improve the efficacy of the separation unit.

[0073] Figure 5b: Installation according to the present disclosure wherein the oxygen-containing effluent and the syngas effluent exiting the solid oxide electrolyser cell working in electrolysis mode (SOEC) are both further used to produce steam to improve the efficacy of the separation unit.

[0074] Figure 6a: Installation according to the present disclosure wherein the oxygen-containing effluent exiting the solid oxide electrolyser cell working in electrolysis mode (SOEC) is used to produce steam that is directed to the solid oxide electrolyser cell and to the separation unit.

[0075] Figure 6b: Installation according to the present disclosure wherein the oxygen-containing effluent exiting the solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) is used to produce steam that is directed to the solid oxide electrolyser cell and to the separation unit. Figure 7a: Installation according to the present disclosure wherein the oxygen-containing effluent and the hydrogen-rich effluent exiting the solid oxide electrolyser cell working in electrolysis mode (SOEC) are both used to produce steam that is directed to the solid oxide electrolyser cell and to the separation unit.

[0076] Figure 7b: Installation according to the present disclosure wherein the oxygen-containing effluent and the syngas effluent exiting the solid oxide electrolyser cell working in coelectrolysis mode (co-SOEC) are both used to produce steam that is directed to the solid oxide electrolyser cell and to the separation unit.

[0077] Figure 8a: Installation according to the present disclosure wherein the oxygen-containing effluent is used to preheat a stream of steam entering a steam pressure-reducing device. The methanol-generating unit works in combination with a solid oxide electrolyser cell working in electrolysis mode (SOEC).

[0078] Figure 8b: Installation according to the present disclosure wherein the oxygen-containing effluent is used to preheat a stream of steam entering a steam pressure-reducing device. The methanol-generating unit works in combination with a solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC).

[0079] Figure 9a: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device is used to produce steam at medium pressure ( / .e., above 0.30 MPa) that is then directed to the separation unit. The methanol-generating unit works in combination with a solid oxide electrolyser cell working in electrolysis mode (SOEC).

[0080] Figure 9b: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device is used to produce steam at medium pressure ( / .e., above 0.30 MPa) that is then directed to the separation unit. The methanol-generating unit works in combination with a solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC).

[0081] Figure 10a: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device and the hydrogen-rich effluent exiting the solid oxide electrolyser cell working in electrolysis mode (SOEC) are both used to produce steam that is then directed to the separation unit.

[0082] Figure 10b: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device and the syngas effluent exiting the solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) are both used to produce steam that is then directed to the separation unit.

[0083] Figure 11a: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device is used to produce steam that is then directed to the separation unit and to the solid oxide electrolyser cell working in electrolysis mode (SOEC).

[0084] Figure 11b: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device is used to produce steam that is then directed to the separation unit and to the solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC).

[0085] Figure 12a: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device and the hydrogen-rich effluent exiting the solid oxide electrolyser cells working in electrolysis mode (SOEC) are both used to produce steam at medium pressure ( / .e., above 0.30 MPa) that is then directed to the separation unit and to the solid oxide electrolyser cell.

[0086] Figure 12b: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device and the syngas effluent exiting the solid oxide electrolyser cells working in co-electrolysis mode (co-SOEC) are both used to produce steam at medium pressure ( / .e., above 0.30 MPa) that is then directed to the separation unit and to the solid oxide electrolyser cell.

[0087] Figure 13a: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device is used to produce steam at low pressure ( / .e., below 0.30 MPa) that is then directed to the separation unit. The methanol-generating unit works in combination with a solid oxide electrolyser cells working in electrolysis mode (SOEC).

[0088] Figure 13b: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device is used to produce steam at low pressure ( / .e., below 0.30 MPa) that is then directed to the separation unit. The methanol-generating unit works in combination with a solid oxide electrolyser cells working in co-electrolysis mode (co-SOEC).

[0089] Figure 14a: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device and the hydrogen-rich effluent exiting the solid oxide electrolyser cells working in electrolysis mode (SOEC) are both used to produce steam at low pressure ( / .e., below 0.30 MPa) that is then directed to the separation unit.

[0090] Figure 14b: Installation according to the present disclosure wherein an oxygen outflow resulting from the preheating of stream of steam entering a steam pressure-reducing device and the syngas effluent exiting the solid oxide electrolyser cells working in co-electrolysis mode (co-SOEC) are both used to produce steam at low pressure ( / .e., below 0.30 MPa) that is then directed to the separation unit.

[0091] Figure 15a: Installation according to the present disclosure comprising a methanol-generating unit upstream of a separation unit. Steam at medium pressure ( / .e., above 0.30 MPa) is directed from a steam pressure-reducing device to the solid oxide electrolyser cell working in electrolysis mode (SOEC). A compressor is upstream to the reactor of the methanolgenerating unit and generates heat upon pressure increase of the hydrogen-rich effluent and the carbon oxides feedstock, said heat serving to produce steam fed to the solid oxide electrolyser cell.

[0092] Figure 15b: Installation according to the present disclosure comprising a methanol-generating unit upstream of a separation unit. Steam at medium pressure ( / .e., above 0.30 MPa) is directed from a steam pressure-reducing device to the solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC). A compressor is upstream to the reactor of the methanolgenerating unit and generates heat upon pressure increase of the syngas effluent, said heat serving to produce steam fed to the solid oxide electrolyser cell.

[0093] Detailed description

[0094] For the purpose of the disclosure, the following definitions are given.

[0095] The terms "comprising", "comprises" and "comprised of" as used herein are synonymous with "including", "includes" or "containing", "contains", and are inclusive or open-ended and do not exclude additional, non-recited members, elements or method steps. The terms "comprising", "comprises" and "comprised of" also include the term “consisting of”.

[0096] The recitation of numerical ranges by endpoints includes all integer numbers and, where appropriate, fractions subsumed within that range (e.g., 1 to 5 includes 1 , 2, 3, 4, 5 when referring to, for example, a number of elements, and can also include 1.5, 2, 2.75 and 3.80, when referring to, for example, measurements). The recitation of endpoints also includes the recited endpoint values themselves (e.g., from 1.0 to 5.0 includes both 1.0 and 5.0). Any numerical range recited herein is intended to include all sub-ranges subsumed therein.

[0097] The reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. The particular features, structures, characteristics or embodiments may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the disclosure and form different embodiments, as would be understood by those in the art.

[0098] The unit “kilowatt hours per kilogram of methanol” (kWh / kgMeon) is the reference unit used to measure or indicate the density of energy contained or storable in methanol.

[0099] The value “0 barg” (relative pressure) corresponds to a difference of pressure with respect to the atmospheric pressure. Therefore, 0 barg = 1 atm = 101325 Pa (absolute pressure, namely the pressure measured with respect to the vacuum) or 0.101325 MPa, rounded to 0.1 MPa.

[0100] The consumption gain in the methanol production have been simulated using the software ProSimPlus.

[0101] The installations represented at figures 1a and 1 b schematize a methanol-generating unit which is upstream of a separation unit and in fluidic connection with it. The methanolgenerating unit comprises one reactor 100 which is for example in fluidic connection with the separation unit. Indeed, there is a fluidic connection between the reactor 100 and the separation unit, in particular with the distillation column 200. This line conveys the reactor effluent 150 from the reactor 100 to the separation unit. Each reactor comprises a cooling device. The separation unit, such as one or more distillation columns 200, preferably three distillation columns that can be arranged in series, comprises a temperature-regulating device 250. The installations further comprise at least one steam pressure-reducing device, for example a turbine 300. The one or more steam pressure-reducing devices are placed downstream of the cooling device and upstream of the temperature-regulating device. The methanol-generating unit and the separation unit are in combination with one or more solid oxide electrolyser cells 400 which works either in electrolysis mode (figure 1a) or in coelectrolysis mode (figure 1 b). The steam pressure-reducing device comprises at least one steam pressure regulator, which can be one or more pressure control valves (PCV) which are used to reduce the pressure of first stream 3 exiting the cooling device. Upon the pressure reduction of the first stream 3, the steam pressure-reducing device produces electricity and / or work, as schematized by the arrow 9. The second stream 5 exiting the steam pressurereducing device can be therefore used to regulate the thermal energy of the separation unit. The condensate that is the liquid formed when the pressure of a condensable gas is reduced due to (partial) condensation of the gas itself, and that is present into the first stream 3, is optionally removed through a gas / liquid separation column 500, so that a third steam 7 is recovered together with a stream 8 comprising the condensate. The third stream 7 can also be used to regulate the thermal energy of the separation unit. A complementary stream of steam 11 can be supplemented to the second stream 5 and / or to the third stream 7, preferably the complementary stream of steam 11 is supplemented to the third stream 7. For example, the complementary stream of steam 11 is at a pressure ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa.

[0102] In the installation represented at figure 2a, namely when the second stream 5 exiting the turbine is at a pressure P2 of 0.5 MPa and when a one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) is coupled to the methanol-generating unit and to the separation unit, the process of methanol production is consuming 10.98 kWh / kgMeon.

[0103] In the installation represented at figure 2b, namely when the second stream 5 exiting the turbine is at a pressure P2 of 0.5 MPa and when a one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) is coupled to the methanol-generating unit and to the separation unit, the process of methanol production is consuming 10.26 kWh / kgMeon.

[0104] Steam production for enhancing the efficacy of the solid oxide electrolyser cell

[0105] The present disclosure relates to a heat management method in a methanol-generating unit, said method is remarkable in that it comprises the following steps: a) providing a methanol-generating unit and a separation unit, wherein the separation unit is placed downstream of the methanol-generating unit and is in fluidic connection with it, wherein said separation unit comprises a temperature-regulating device 250, and wherein said methanol-generating unit comprise one or more reactors 100 each comprising a cooling device; b) operating said at least one reactor 100 under first operating conditions, said first operating conditions comprising at least regulating the thermal energy of said at least one reactor 100; wherein the step of regulating the thermal energy comprises adjusting the temperature of the cooling device with water 1. This step of adjusting the temperature of the cooling device amounts to adjusting the temperature of the reactor 100; c) recovering from said cooling device, after said step of regulating the thermal energy, a first stream 3, said first stream 3 comprising steam at a pressure P1; d) decreasing the pressure of said first stream 3 so as to recover a second stream 5, said second stream 5 comprising steam at a pressure P2, wherein P2 < P1 ; e) providing one or more solid oxide electrolyser cells 400; f) feeding said one or more solid oxide electrolyser cells 400 with at least the second stream 5 recovered at step (d) or with a mixture comprising carbon dioxide and at least the second stream 5 recovered at step (d); g) working said one or more solid oxide electrolyser cells 400 under second operating conditions so as to generate a hydrogen-rich effluent 15 or a syngas effluent 19, said second operating conditions comprising at least electrical power and a temperature higher than 400°C; wherein the first operating conditions of step (b) comprise feeding said at least one reactor with either a carbon oxides feedstock and the hydrogen-rich effluent 15 generated at step (g) or the syngas effluent 19 generated at step (g).

[0106] The heat management method described above is advantageously carried out in an installation for producing methanol remarkable in that the installation comprises: a methanol-generating unit and a separation unit, wherein said separation unit is placed downstream of the methanol-generating unit and is in fluidic connection with it, wherein the separation unit comprises a temperature-regulating device 250, and wherein the methanol-generating unit comprising one or more reactors 100, each reactor 100 comprising a cooling device; one or more solid oxide electrolyser cells 400, wherein said one or more solid oxide electrolyser cells 400 are placed downstream of said cooling device, and in fluidic connection with it; each of said one or more solid oxide electrolyser cells 400 comprising a hydrogen-output line to direct a hydrogen-rich effluent 15 or a syngas effluent 19 out of said solid oxide electrolyser cell 400; and wherein the installation further comprises a line fluidically connecting the hydrogen-output line to the one or more reactors 100 of the methanol-generating unit; at least one steam pressure-reducing device, the steam pressure-reducing device being placed downstream of said cooling device and upstream of said one or more solid oxide electrolyser cells 400; a first line connecting fluidically the cooling device to the one or more steam pressurereducing devices; a second line connecting fluidically the one or more steam pressure-reducing devices to the one or more solid oxide electrolyser cells 400, and wherein the one or more steam pressure-reducing devices comprise at least one steam pressure regulator.

[0107] For example, the one or more steam pressure regulators are one or more pressure control valves.

[0108] For example, the steam pressure-reducing device is at least one turbine or at least one Venturi scrubber, preferably at least one turbine.

[0109] The one or more solid oxide electrolyser cells 400 provided at step (e) have each an anode and a cathode and comprise a solid oxide electrolyte between the anode and the cathode. The anode, the cathode and the solid oxide electrolyte are each composed of one or more ceramic materials. The temperature at which said one or more solid oxide electrolyser cells are working under electrical power can be higher than 425°C, preferably higher than 450°C, more preferably higher than 475°C, even more preferably higher than 500°C. For example, the temperature at which said one or more solid oxide electrolyser cells are working under electrical power is ranging between 400°C and 1000°C, or between 450°C and 900°C, preferably between 500°C and 890°C, more preferably between 550°C and 880°C, even more preferably between 600°C and 870°C, most preferably between 700°C and 860°C.

[0110] For example, the one or more solid oxide electrolyser cells are operated at a current density that is ranging between 0.2 A / cm2and 5 A / cm2, preferably between 0.4 A / cm2and 4.8 A / cm2.

[0111] For example, the one or more solid oxide electrolyser cells are operated at an electrical potential ranging between 0.2 V / cell and 2.0 V / cell, preferably between 0.4 V / cell and 1.8 V / cell.

[0112] For example, the hydrogen-rich effluent comprises at least 50 vol.% of hydrogen based on the total volume of said effluent; preferably at least 60 vol.%, more preferably at least 70 vol.%, even more preferably at least 80 vol.%, most preferably at least 90 vol.%, even most preferably at least 99 vol.%.

[0113] For example, the syngas effluent comprises carbon monoxide, hydrogen, carbon dioxide and optionally methane. With preference, the syngas effluent comprises between 15 vol.% and 40 vol.% of carbon monoxide (CO), between 25 vol.% and 35 vol.% of hydrogen (H2), between 2 vol.% and 15 vol.% of carbon dioxide (CO2), and between 0 vol.% and 5 vol.% of methane (CH4) all based on the total volume of said effluent. Indeed, for example, the syngas effluent comprises between 15 vol.% and 40 vol.% of carbon monoxide (CO) based on the total volume of said effluent. For example, the syngas effluent comprises between 25 vol.% and 35 vol.% of hydrogen (H2) based on the total volume of said effluent. For example, the syngas effluent comprises between 2 vol.% and 15 vol.% of carbon dioxide (CO2) based on the total volume of said effluent. For example, the syngas effluent comprises between 0 vol.% and 5 vol.% of methane (CH4) based on the total volume of said effluent.

[0114] With preference, the carbon oxides of the carbon oxides feedstock provided to said at least one reactor are selected from CO2 and / or CO. With preference, the pressure of the carbon oxides feedstock in the first operating conditions used in step (b) is ranging between 0.1 MPa and 12.0 MPa, preferably between 0.5 MPa, and 9.5 MPa, more preferably between 1.0 MPa and 9.0 MPa; even more preferably between 1.5 MPa and 8.5 MPa, most preferably between 2.0 MPa and 8.0 MPa.

[0115] With preference, the pressure of the stream of hydrogen in the first operating conditions used in step (b) is ranging between 0.1 MPa and 12.0 MPa, preferably between 0.5 MPa, and 9.5 MPa, more preferably between 1.0 MPa and 9.0 MPa; even more preferably between 1.5 MPa and 8.5 MPa, most preferably between 2.0 MPa and 8.0 MPa. For example, the first operating conditions of step (b) comprise a temperature ranging between 200°C and 320°C, preferably between 220°C and 275°C. When a stream of syngas is used, the pressure of said stream is similar, namely it is ranging between 0.1 MPa and 12.0 MPa, preferably between 0.5 MPa, and 9.5 MPa, more preferably between 1.0 MPa and 9.0 MPa; even more preferably between 1.5 MPa and 8.5 MPa, most preferably between 2.0 MPa and 8.0 MPa.

[0116] For example, the first operating conditions of step (b) comprise a start-of-run outlet reactor temperature ranging between 200°C and 320°C, preferably between 220°C and 275°C.

[0117] For example, the water used in step (b) for adjusting the temperature of the cooling device has a pressure ranging between 1.5 MPa and 12.0 MPa, or between 2.2 MPa and 7.0 MPa.

[0118] For example, the water used in step (b) for adjusting the temperature of the cooling device has a temperature ranging between 100°C and 200°C, or between 120°C and 150°C.

[0119] For example, the first stream 3 is at a temperature T 1 comprised between 200°C and 325°C, or between 200°C and 300°C, preferably between 205°C and 295°C, more preferably between 210°C and 290°C, even more preferably between 215°C and 285°C, most preferably between 220°C and 280°C, even most preferably between 220°C and 275°C. For example, the pressure P1 of the first stream 3 is comprised between 1.5 MPa and 12.0 MPa, or between 2.2 MPa and 7.0 MPa. The pressure P1 of the first stream 3 is measured at dew point.

[0120] For example, the pressure P2 of the second stream 5 is ranging between 0.31 MPa and 1 .30 MPa, preferably between 0.32 MPa and 1.29 MPa, preferably between 0.33 MPa and 1.28 MPa, more preferably between 0.34 MPa and 1.27 MPa, even more preferably between 0.35 MPa and 1.26 MPa, most preferably between 0.36 MPa and 1.25 MPa.

[0121] The step (d) of decreasing the pressure of said first stream 3 further produces electrical energy. Thus, when electrical energy is produced, the method can further comprise the step of supplying said electrical energy to said one or more solid oxide electrolyser cells 400 so as to run said one or more solid oxide electrolyser cells 400.

[0122] As the methanol-generating unit provided at step (a) comprises one or more compressors, and the step (d) of decreasing the pressure of said first stream further produces electrical energy and / or shaft work; the method can further comprise the step of supplying said electrical energy and / or shaft work to said one or more compressors so as to run the one or more compressors comprised within the methanol-generating unit.

[0123] The second stream 5 comprising steam at a pressure P2 can further comprise a condensate; and the method further advantageously comprises the step of separating the steam from said condensate so as to recover a third stream 7, said third stream 7 comprising steam at a pressure P3, wherein P3 is equal or inferior to P2. A stream 8 comprising a condensate is also recovered. Thus, advantageously, the installation further comprises a gas-liquid separator 500, said gas-liquid separator 500 being placed on the second line downstream of and in fluidic connection with said at least one steam pressure-reducing device, said gas-liquid separator 500 comprising an overhead fluidically connected to the one or more solid oxide electrolyser cells 400.

[0124] With preference, the step of feeding the one or more solid oxide electrolyser cells 400 carried in step (f) further comprises feeding said one or more solid oxide electrolyser cells 400 with the third stream 7, so as to generate an oxygen-containing effluent 13 and a hydrogen-rich effluent, or with a mixture comprising carbon dioxide 17 and the third stream 7, so as to generate an oxygen-containing effluent 13 and a syngas effluent 19.

[0125] For example, the pressure P3 of the third stream 7 is ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa. The pressure P3 of the third stream 7 is measured at dew point.

[0126] The pressure P1 of the first stream and / or the pressure P3 of the third stream is measured at dew point. The pressure P2 of the second stream is not measured at dew point because it is related to a steam that is at the exit of the steam pressure-reducing device and which subsequently comprises a condensate.

[0127] This heat management method is implemented in the installations represented at figures 3a and 3b.

[0128] In the installation of figure 3a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the hydrogenrich effluent 15 is fed to the one or more reactors 100 of the methanol-generating unit, the process of methanol production is consuming at most 11 .00 kWh / kgMeOH, preferably at most 10.95 kWh / kgMeoH.

[0129] In the installation of figure 3b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the syngas effluent 19 is fed to the one or more reactors 100 of the methanol-generating unit, the process of methanol production is consuming at most 10.20 kWh / kgMeoH, preferably at most 10.15 kWh / kgMeoH.

[0130] In essence, the present disclosure relates therefore to a heat management method in a methanol-generating unit remarkable in that the reactor 100 of the methanol-generating unit comprises a cooling device and wherein the second and / or third stream comprising steam (5, 7) recovered from said cooling device has a pressure that is suitable for being fed into the one or more solid oxide electrolyser cells 400, so as to provide a hydrogen-rich effluent 15 or a syngas effluent 19 that is directed to the methanol-generating unit, and therefore improve the efficiency of the methanol process.

[0131] With preference, the method further comprises the step of increasing the pressure of the hydrogen-rich effluent 15 or the syngas effluent 19 before using it as stream of hydrogen in the first operating conditions used at step (b).

[0132] Steam production thanks to the oxygen-containing effluent exiting the solid oxide electrolyser cell and improvement of the efficacy of the separation unit thanks to the produced steam

[0133] The previous configuration can be improved by using the oxygen-containing effluent 13 generated at step (g). Indeed, as the step (g) of working said one or more solid oxide electrolyser cells 400 under second operating conditions also generates an oxygen-containing effluent 13, the method can comprise the following steps: h) providing a water stream 23; i) transferring the thermal energy of at least the oxygen-containing effluent 13 to said water stream 23 so as to produce an additional stream 25 of steam; and j) transferring the thermal energy of the additional stream 25 of steam to the temperature-regulating device of the separation unit.

[0134] This heat management method is implemented in the installations represented at figures 4a and 4b.

[0135] Thus, the installation can further comprise a water supply upstream of a first heat exchanger, and a water line directing a water stream 23 from said water supply to said first heat exchanger, and each of said one or more solid oxide electrolyser cells 400 comprises an oxygen-output line to direct an oxygen-containing effluent 13 out of said solid oxide electrolyser cell 400; wherein the oxygen-output line is in connection with said first heat exchanger so that the thermal energy of said oxygen-containing effluent 13 is transferred to the water stream 23 of the water supply to produce an additional stream 25 of steam that is directed into an additional line connecting the first heat exchanger and the temperature-regulating device 250 so that the thermal energy of the additional stream 25 of steam is transferred to the temperature-regulating device 250.

[0136] In the installation of figure 4a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) so as to generate a hydrogen-rich effluent 15 that is directed to the methanol-generating unit and when the oxygencontaining effluent 13 is used to produce steam that is then directed to the separation unit, the process of methanol production is consuming at most 10.75 kWh / kgMeon, preferably at most 10.70 kWh / kgMeOH.

[0137] In the installation of figure 4b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) so as to generate a syngas effluent 19 that is directed to the methanol-generating unit and when the oxygencontaining effluent 13 is used to produce steam that is then directed to the separation unit, the process of methanol production is consuming at most 9.95 kWh / kgMeon, preferably at most 9.90 kWh / kgMeOH. Using the hydrogen-rich effluent or the syngas effluent to further improve the methanol production

[0138] As step (g) generates respectively a hydrogen-rich effluent 15 or a syngas effluent 19, the heat management method can further comprise a step of transferring the thermal energy of either the hydrogen-rich effluent 15 or the syngas effluent 19 to the water stream 23 before the step of transferring the thermal energy of at least the oxygen-containing effluent 15 to said water stream 23 so as the produce the additional stream 25 of steam.

[0139] This is implemented in the installations represented at figures 5a and 5b.

[0140] Thus, the installation can further comprise a second heat exchanger placed on the water line upstream of the first heat exchanger, and the installation further comprises a third line between the hydrogen-output line and the second heat exchanger so that the thermal energy of the hydrogen-rich effluent 15 or the syngas effluent 19 is transferred to the water stream 23 directed in the water line upstream of the first heat exchanger.

[0141] In the installation of figure 5a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) so as to generate a hydrogen-rich effluent 15 that is directed to the methanol-generating unit and when both the oxygen-containing effluent 13 and the hydrogen-rich effluent 15 are used to produce steam that is then directed to the separation unit, the process of methanol production is consuming at most 10.70 kWh / kgMeOH, preferably at most 10.65 kWh / kgMeOH.

[0142] In the installation of figure 5b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) so as to generate a syngas effluent 19 that is directed to the methanol-generating unit and when both the oxygencontaining effluent 13 and the syngas effluent 19 are used to produce steam that is then directed to the separation unit, the process of methanol production is consuming at most 9.95 kWh / kgMeOH, preferably at most 9.90 kWh / kgMeOH.

[0143] Steam production thanks to the oxygen-containing effluent for improving both the efficacy of the separation unit and the functioning of the solid oxide electrolyser cell

[0144] The step (j) of transferring the thermal energy of the additional stream 25 of steam to the temperature-regulating device 250 of the separation unit is a step of transferring the thermal energy of a first part 27 of said additional stream of steam. Then, the method further comprises the step of feeding a second part 29 of the additional stream of steam to said one or more solid oxide electrolyser cells 400 during step (f).

[0145] This is implemented in the installations represented at figures 6a and 6b. Thus, the installation can further comprise a line connecting the first heat exchanger and the one or more solid oxide electrolyte cells so that at least a part of the additional stream 25 of steam is directed into the one or more solid oxide electrolyte cells 400.

[0146] In the installation of figure 6a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygencontaining effluent 13 is used to produce steam that is then directed to both the separation unit and to the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 10.70 kWh / kgMeOH, preferably at most 10.65 kWh / kgMeOH.

[0147] In the installation of figure 6b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent 13 is used to produce steam that is then directed to both the separation unit and to the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 9.95 kWh / kgMeOH, preferably at most 9.90 kWh / kgMeoH.

[0148] Steam production thanks to both the oxygen-containing effluent and the hydrogen effluent / syngas effluent for improving both the efficacy of the separation unit and the functioning of the solid oxide electrolyser cell

[0149] With preference, as step (g) generates respectively a hydrogen-rich effluent 15 or a syngas effluent 19, the method further comprises a step of transferring the thermal energy of either the hydrogen-rich effluent 15 or the syngas effluent 19 to the water stream 23 before the step of transferring the thermal energy of at least the oxygen-containing effluent 13 to said water stream 23 so as to produce the additional stream 25 of steam.

[0150] Thus, the installation can further comprise a line connecting the first heat exchanger and the one or more solid oxide electrolyte cells 400 so that at least a part of the additional stream 25 of steam is directed into the one or more solid oxide electrolyte cells 400.

[0151] This is implemented in the installations represented at figures 7a and 7b, in which the as- produced additional stream of steam 25 is separated into a first part 27 of additional stream of steam to transfer its thermal energy to the thermal-regulating device 250 of the separation unit and into a second part 29 of additional stream of steam to feed to one or more solid oxide electrolyser cells 400.

[0152] In the installation of figure 7a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when both the oxygen-containing effluent and the hydrogen-rich effluent are used to produce steam that is then directed to both the separation unit and the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 10.65 kWh / kgMeOH, preferably at most 10.60 kWh / kgMeoH.

[0153] In the installation of figure 7b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when both the oxygen-containing effluent and the syngas effluent are used to produce steam that is then directed to both the separation unit and the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 9.90 kWh / kgMeoH, preferably at most 9.85 kWh / kgMeoH.

[0154] Use of the oxygen-containing effluent to preheat the first stream entering into the steam pressure-reducing device

[0155] The method can further comprise the step of transferring the thermal energy of the oxygen- containing effluent 13 generated at step (g) to the first stream recovered at step (c). The steam entering the steam pressure-reducing device, such as the turbine 300, is thus preheated thanks to the thermal energy of the oxygen-containing effluent 13.

[0156] This is implemented in the installations represented at figures 8a and 8b.

[0157] Thus, the installation can further comprise a third heat exchanger placed on the first line upstream of the one or more steam pressure-reducing devices, and a fourth line connecting the oxygen-output line and the third heat exchanger, so that the thermal energy of the oxygenrich effluent 13 is transferred to a stream of water circulating within the first line.

[0158] In the installation of figure 8a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygen- containing effluent is used to preheat the first stream 3 entering into the steam pressurereducing device, the process of methanol production is consuming at most 10.95 kWh / kgMeoH, preferably at most 10.90 kWh / kgMeoH.

[0159] In the installation of figure 8b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device, the process of methanol production is consuming at most 10.15 kWh / kgMeoH, preferably at most 10.10 kWh / kgMeoH. Production of steam at medium pressure (i.e., above 0.30 MPa) by using the oxygen outflow and directing said steam to the separation unit

[0160] For example, the step of transferring the thermal energy of said oxygen-containing effluent 13 generated at step (g) to the first stream 3 recovered at step (c) further generates an oxygen outflow 21 ; and wherein the additional stream 25 of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa to 1.29 MPa by transferring the thermal energy of the oxygen outflow 21 to said water stream 23; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of the additional stream of steam at a pressure ranging between 0.30 MPa to 1.29 MPa to the temperature-regulating device 250 of the separation unit.

[0161] For example, the additional stream 25 of steam is generated at a pressure ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa.

[0162] With preference, when the one or more solid oxide electrolyser cells are operated under electrolysis mode (SOEC), said step (j) can be accompanied by a step of providing a complementary stream 11 of steam at a pressure ranging between 0.30 MPa and 1.29 MPa to the temperature-regulating device of the separation unit.

[0163] This is implemented in the installations represented at figures 9a and 9b.

[0164] Thus, the installation further comprises a water supply upstream of a fourth heat exchanger, and a water line directing a water stream 23 from said water supply to said fourth heat exchanger, wherein the installation further comprises a fifth line connecting the third heat exchanger to the fourth heat exchanger to direct an oxygen outflow 21 from the third heat exchanger to the fourth heat exchanger, so that the thermal energy of the oxygen outflow 21 is transferred to the water stream 23 directed into the water line to produce an additional stream 25 of steam at a pressure ranging between 0.30 MPa and 1.29 MPa that is directed into an additional line connecting the fourth heat exchanger to the temperature-regulating device 250.

[0165] In the installation of figure 9a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygencontaining effluent is used to preheat the first stream 3 entering into the steam pressurereducing device generating subsequently an oxygen outflow that is used to produce steam which is totally directed to enhance the efficacy of the separation unit, the process of methanol production is consuming at most 10.75 kWh / kgMeon, more preferably at most 10.70 kWh / kgMeoH.

[0166] In the installation of figure 9b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used to produce steam which is totally directed to enhance the efficacy of the separation unit, the process of methanol production is consuming preferably at most 9.95 kWh / kgMeoH, more preferably at most 9.90 kWh / kgMeoH.

[0167] Steam production by using both the oxygen outflow and the hydrogen-rich effluent and directing said steam to the separation unit

[0168] As step (g) generates respectively a hydrogen-rich effluent 15 or a syngas effluent 19, the method can further comprise a step of transferring the thermal energy of either the hydrogenrich effluent 15 or the syngas effluent 19 to the water stream 23 before the step of transferring the thermal energy of the oxygen outflow 21 to said water stream 23 so as the produce the additional stream 25 of steam generated at a pressure ranging between 0.30 MPa to 1.29 MPa. This additional stream 25 of steam is then directed to the separation unit, wherein its thermal energy is transferred to the temperature-regulating device 250.

[0169] With preference, when the one or more solid oxide electrolyser cells are operated under electrolysis mode (SOEC), said step (j) can be accompanied by a step of providing a complementary stream 11 of steam at a pressure ranging between 0.30 MPa and 1.29 MPa to the temperature-regulating device of the separation unit.

[0170] This is implemented in the installations represented at figures 10a and 10b.

[0171] Thus, the installation can further comprise a fifth heat exchanger placed on the water line upstream of the fourth heat exchanger, and the installation further comprises a sixth line between the hydrogen-output line and the fifth heat exchanger so that the thermal energy of the hydrogen-rich effluent 15 or the syngas effluent 19 is transferred to the water stream 23 directed in the water line upstream of the fourth heat exchanger. Then, in the fourth heat exchanger, the thermal energy of the oxygen outflow 21 is transferred to the water stream 23 to produce the additional stream 25 of steam at a pressure ranging between 0.30 MPa and 1.29 MPa that is directed into an additional line connecting the fourth heat exchanger to the temperature-regulating device 250. In the installation of figure 10a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used with the hydrogen-rich effluent to produce steam which is totally directed to enhance the efficacy of the separation unit, the process of methanol production is consuming at most 10.70 kWh / kgMeOH, more preferably at most 10.65 kWh / kgMeOH.

[0172] In the installation of figure 10b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used with the syngas effluent to produce steam which is totally directed to enhance the efficacy of the separation unit, the process of methanol production is consuming at most 9.90 kWh / kgMeOH, preferably at most 9.85 kWh / kgMeOH.

[0173] Steam production by using the oxygen outflow and directing said steam to both the separation unit and the solid oxide electrolyser cells

[0174] For example, the step of transferring the thermal energy of said oxygen-containing effluent 13 generated at step (g) to the first stream 3 recovered at step (c) further generates an oxygen outflow 21 ; and wherein the additional stream 25 of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa to 1.29 MPa by transferring the thermal energy of the oxygen outflow 21 to said water stream 23; and the step (j) of transferring the thermal energy of the additional stream of steam to the temperature-regulating device of the separation unit is a step of transferring the thermal energy of the additional stream of steam at a pressure ranging between 0.30 MPa to 1 .29 MPa to the temperature-regulating device of the separation unit.

[0175] For example, the additional stream 25 of steam is generated at a pressure ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa.

[0176] With preference, when the one or more solid oxide electrolyser cells are operated under electrolysis mode (SOEC), said step (j) can be accompanied by a step of providing a complementary stream 11 of steam at a pressure ranging between 0.30 MPa and 1.29 MPa to the temperature-regulating device of the separation unit. The as-produced additional stream of steam 25 generated at a pressure ranging between 0.30 MPa to 1.29 MPa can be separated into a first part 27 of additional stream of steam to transfer its thermal energy to the thermal-regulating device 250 of the separation unit and into a second part 29 of additional stream of steam to feed to one or more solid oxide electrolyser cells 400.

[0177] Thus, the installation can further comprise a line connecting the fourth heat exchanger to the one or more solid oxide electrolyte cells 400 so that at least a part of the additional stream 25 of steam at a pressure ranging between 0.30 MPa and 1.29 MPa is directed into the one or more solid oxide electrolyte cells 400.

[0178] This is implemented in the installations represented at figures 11a and 11 b.

[0179] In the installation of figure 11a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygen-containing effluent 13 is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow 21 that is used to produce steam at a pressure ranging between 0.30 MPa to 1.29 MPa which is directed to enhance both the efficacy of the separation unit and of the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 10.70 kWh / kgMeOH, preferably at most 10.65 kWh / kgMeOH.

[0180] In the installation of figure 11 b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent 13 is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow 21 that is used to produce steam at a pressure ranging between 0.30 MPa to 1.29 MPa which is directed to enhance both the efficacy of the separation unit and of the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 9.95 kWh / kgMeOH, preferably at most 9.90 kWh / kgMeOH.

[0181] Steam production by using both the oxygen outflow and the hydrogen-rich effluent and directing said steam to both the separation unit and the solid oxide electrolyser cells

[0182] As step (g) generates respectively a hydrogen-rich effluent 15 or a syngas effluent 19, the method can further comprise a step of transferring the thermal energy of either the hydrogenrich effluent 15 or the syngas effluent 19 to the water stream 23 before the step of transferring the thermal energy of the oxygen outflow 21 to said water stream 23 so as the produce the additional stream 25 of steam generated at a pressure ranging between 0.30 MPa to 1.29 MPa. A first part 27 of this additional stream of steam is then directed to the separation unit, wherein its thermal energy is transferred to the temperature-regulating device 250; while a second part 29 of this additional stream of steam is then fed to the one or more solid oxide electrolyser cells 400.

[0183] Thus, the installation can further comprise a fifth heat exchanger placed on the water line upstream of the fourth heat exchanger, and the installation further comprises a sixth line between the hydrogen-output line and the fifth heat exchanger so that the thermal energy of the hydrogen-rich effluent 15 or the syngas effluent 19 is transferred to the water stream 23 directed in the water line upstream of the fourth heat exchanger. Then, in the fourth heat exchanger, the thermal energy of the oxygen outflow 21 is transferred to the water stream 23 to produce the additional stream 25 of steam at a pressure ranging between 0.30 MPa and 1.29 MPa that is directed into an additional line connecting the fourth heat exchanger to the temperature-regulating device 250 and the installation further comprises a line connecting the fourth heat exchanger to the one or more solid oxide electrolyte cells 400 so that at least a part of the additional stream 25 of steam at a pressure ranging between 0.30 MPa and 1 .29 MPa is directed into the one or more solid oxide electrolyte cells 400.

[0184] This is implemented in the installations represented at figures 12a and 12b.

[0185] In the installation of figure 12a, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used with the hydrogen-rich effluent to produce steam which is directed to enhance both the efficacy of the separation unit and of the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 10.65 kWh / kgMeOH, preferably at most 10.60 kWh / kgMeoH.

[0186] In the installation of figure 12b, namely when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used with the syngas effluent to produce steam which is directed to enhance both the efficacy of the separation unit and of the one or more solid oxide electrolyser cells 400, the process of methanol production is consuming at most 9.90 kWh / kgMeoH, preferably at most 9.85 kWh / kgMeoH.

[0187] Production of steam at low pressure (i.e., below 0.30 MPa) by using the oxygen outflow and directing said steam to the separation unit The water stream 24 provided at step (h) can be at a pressure below 0.30 MPa, preferably below 0.29 MPa, more preferably below 0.28 MPa, even more preferably below 0.27 MPa. For example, the water stream 24 provided at step (h) can be at a pressure ranging between 0.10 MPa and 0.30 MPa, preferably between 0.11 MPa and 0.29 MPa, more preferably between 0.12 MPa and 0.28 MPa, even more preferably 0.13 MPa and 0.27 MPa. Such water stream

[0188] 24 is a low-pressurized water stream.

[0189] Then, for example, when there is a step of transferring the thermal energy of said oxygencontaining effluent 13 generated at step (g) to the first stream 3 recovered at step (c) to further generates an oxygen outflow 21 which is then subjected to a transfer of its thermal energy to the water stream 24 provided at step (h), the additional stream 25 of steam can be generated at a pressure below 0.30 MPa. Then a step (j) of transferring the thermal energy of said additional stream 25 of steam at a pressure below 0.30 MPa to the temperature-regulating device 250 of the separation unit is carried out.

[0190] For example, the additional stream 25 of steam is at a pressure below 0.30 MPa, preferably below 0.29 MPa, more preferably below 0.28 MPa, even more preferably below 0.27 MPa.

[0191] For example, the additional stream 25 of steam is at a pressure ranging between 0.10 MPa and 0.30 MPa, preferably between 0.11 MPa and 0.29 MPa, more preferably between 0.12 MPa and 0.28 MPa, even more preferably 0.13 MPa and 0.27 MPa.

[0192] With preference, said step (j) is accompanied by a step of providing a backup stream 30 of steam at a pressure below 0.30 MPa to the temperature-regulating device of the separation unit.

[0193] For example, the backup stream 30 of steam is at a pressure below 0.30 MPa, preferably below 0.29 MPa, more preferably below 0.28 MPa, even more preferably below 0.27 MPa.

[0194] For example, the backup stream 30 of steam is at a pressure ranging between 0.10 MPa and 0.30 MPa, preferably between 0.11 MPa and 0.29 MPa, more preferably between 0.12 MPa and 0.28 MPa, even more preferably 0.13 MPa and 0.27 MPa.

[0195] Thus, the installation further comprises a water supply upstream of a fourth heat exchanger, and a water line directing a water stream 24 from said water supply to said fourth heat exchanger, wherein the installation further comprises a fifth line connecting the third heat exchanger to the fourth heat exchanger to direct an oxygen outflow 21 from the third heat exchanger to the fourth heat exchanger, so that the thermal energy of the oxygen outflow 21 is transferred to the water stream 24 directed into the water line to produce an additional stream

[0196] 25 of steam at a pressure below 0.30 MPa that is directed into an additional line connecting the fourth heat exchanger to the temperature-regulating device 250. This is implemented in the installation represented at figure 13a when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used to produce steam from a water stream 24 at a pressure below 0.30 MPa and which is directed to enhance with a backup stream 30 of steam the efficacy of the separation unit, the process of methanol production is consuming at most 10.70 kWh / kgMeOH, preferably at most 10.65 kWh / kgMeoH.

[0197] This is implemented in the installation represented at figure 13b when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used to produce steam from a water stream 24 at a pressure below 0.30 MPa and which is directed to enhance with a backup stream 30 of steam the efficacy of the separation unit, the process of methanol production is consuming at most 10.90 kWh / kgMeoH, preferably at most 10.85 kWh / kgMeoH.

[0198] Production of steam at low pressure f / '.e., below 0.30 MPa) by using both the oxygen outflow and the hydrogen-rich effluent or the syngas effluent and directing said steam to the separation unit

[0199] The water stream 24 provided at step (h) can be at a pressure below 0.30 MPa, preferably below 0.29 MPa, more preferably below 0.28 MPa, even more preferably below 0.27 MPa. For example, the water stream 24 provided at step (h) can be at a pressure ranging between 0.10 MPa and 0.30 MPa, preferably between 0.11 MPa and 0.29 MPa, more preferably between 0.12 MPa and 0.28 MPa, even more preferably 0.13 MPa and 0.27 MPa. Such water stream 24 is a low-pressurized water stream.

[0200] Then, as step (g) generates a hydrogen-rich effluent 15, the method can further comprise a step of transferring the thermal energy of the hydrogen-rich effluent 15 to the water stream 24 before the step of transferring the thermal energy of the oxygen outflow 21 to said water stream 24 so as the produce the additional stream 25 of steam generated at a pressure below 0.30 MPa. Then, step (j) is carried out, in which said step (j) is accompanied by a step of providing a backup stream 30 of steam at a pressure below 0.30 MPa to the temperatureregulating device 250 of the separation unit. For example, the additional stream 25 of steam is at a pressure below 0.30 MPa, preferably below 0.29 MPa, more preferably below 0.28 MPa, even more preferably below 0.27 MPa.

[0201] For example, the additional stream 25 of steam is at a pressure ranging between 0.10 MPa and 0.30 MPa, preferably between 0.11 MPa and 0.29 MPa, more preferably between 0.12 MPa and 0.28 MPa, even more preferably 0.13 MPa and 0.27 MPa.

[0202] For example, the backup stream 30 of steam is at a pressure below 0.30 MPa, preferably below 0.29 MPa, more preferably below 0.28 MPa, even more preferably below 0.27 MPa.

[0203] For example, the backup stream 30 of steam is at a pressure ranging between 0.10 MPa and 0.30 MPa, preferably between 0.11 MPa and 0.29 MPa, more preferably between 0.12 MPa and 0.28 MPa, even more preferably 0.13 MPa and 0.27 MPa.

[0204] Thus, the installation can further comprise a fifth heat exchanger placed on the water line upstream of the fourth heat exchanger, and the installation further comprises a sixth line between the hydrogen-output line and the fifth heat exchanger so that the thermal energy of the hydrogen-rich effluent 15 or the syngas effluent 19 is transferred to the water stream 24 directed in the water line upstream of the fourth heat exchanger. Then, in the fourth heat exchanger, the thermal energy of the oxygen outflow 21 is transferred to the water stream 24 to produce the additional stream 25 of steam at a pressure below 0.30 MPa that is directed into an additional line connecting the fourth heat exchanger to the temperature-regulating device 250.

[0205] This is implemented in the installation represented at figure 14a when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used with the hydrogen-rich effluent 15 to produce steam from a water stream 24 at a pressure below 0.30 MPa and which is directed to enhance with a backup stream 30 of steam the efficacy of the separation unit, the process of methanol production is consuming at most 10.60 kWh / kgMeOH, preferably at most 10.55 kWh / kgMeOH.

[0206] This is implemented in the installation represented at figure 14b when the third stream 7 is directed into the one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the oxygen-containing effluent is used to preheat the first stream 3 entering into the steam pressure-reducing device generating subsequently an oxygen outflow that is used with the syngas effluent 19 to produce steam from a water stream 24 at a pressure below 0.30 MPa and which is directed to enhance with a backup stream 30 of steam the efficacy of the separation unit, the process of methanol production is consuming at most 9.80 kWh / kgMeOH, preferably at most 9.75 kWh / kgMeon.

[0207] Use of heat generated by one or more compressors upstream of the reactor

[0208] As represented at figures 15a and 15b, one or more compressors 700 are placed upstream of the reactor 100 of the methanol-generating unit, namely upstream of the reactor inlet, so that the hydrogen-rich effluent 15 or the syngas effluent 19 exiting the one or more solid oxide electrolyser cells 400 is directed into said one or more compressors 700 before being fed to the reactor 100. Under electrolysis mode (SOEC), a carbon oxides feedstock 16 is also directed into said one or more compressors 700, before being fed to the reactor 100. The step of pressure increase of the hydrogen-rich effluent 15 or the syngas effluent 19 that is performed within said one or more compressors 700 also generates heat. Then, a water stream 23 is provided, and there is a step of transferring the heat generated by said one or more compressors 700 to said water stream 23, so that a second additional stream of steam 39 is generated and then fed to the one or more solid oxide electrolyser cells 400.

[0209] For example, the water stream 23 can be at a pressure ranging between 0.30 MPa and 1.29 MPa, preferably between 0.31 MPa and 1.28 MPa, preferably between 0.32 MPa and 1.27 MPa, more preferably between 0.33 MPa and 1.26 MPa, even more preferably between 0.34 MPa and 1.25 MPa, most preferably between 0.35 MPa and 1.24 MPa. Such water stream 23 is a medium-pressurized water stream.

[0210] With preference, the step of pressure increase of the hydrogen-rich effluent 15 comprises increasing the pressure to a range comprised between 0.32 MPa and 12.0 MPa, preferably between 0.5 MPa, and 9.5 MPa, more preferably between 1.0 MPa and 9.0 MPa; even more preferably between 1.5 MPa and 8.5 MPa, most preferably between 2.0 MPa and 8.0 MPa. With preference, the step of pressure increase of the carbon oxides feedstock 16 comprises increasing the pressure at the same pressure as the pressure of the hydrogen-rich effluent 15, namely to a range comprised between 0.32 MPa and 12.0 MPa, preferably between 0.5 MPa, and 9.5 MPa, more preferably between 1.0 MPa and 9.0 MPa; even more preferably between 1.5 MPa and 8.5 MPa, most preferably between 2.0 MPa and 8.0 MPa.

[0211] In the case of co-electrolysis (co-SOEC), the step of pressure increase of the syngas effluent 19 comprises increasing the pressure to a range comprised between 0.32 MPa and 12.0 MPa, preferably between 0.5 MPa, and 9.5 MPa, more preferably between 1.0 MPa and 9.0 MPa; even more preferably between 1.5 MPa and 8.5 MPa, most preferably between 2.0 MPa and 8.0 MPa. For example, the second additional stream of steam 39 is at a pressure ranging between 0.38 MPa and 1.10 MPa, preferably between 0.39 MPa and 1.00 MPa, more preferably between 0.40 MPa and 0.90 MPa. For example, the second additional stream of steam 39 is at a temperature ranging between 142°C and 184°C, preferably between 143°C and 180°C, more preferably between 144°C and 175°C.

[0212] On these figures, a line connecting the reactor 100 to the separation unit, in particular to the distillation column 200, has been represented. This line conveys the reactor effluent 150 from the reactor 100 to the separation unit.

[0213] In the installation represented at figure 15a, namely when the third stream 7 is directed in one or more solid oxide electrolyser cells 400 working in electrolysis mode (SOEC) and when the hydrogen-rich effluent 15 is fed to one or more compressors 700 prior to entering the reactor 100 of the methanol-generating unit, the process of methanol production is consuming at most 10.90 kWh / kgMeOH, preferably at most 10.85 kWh / kgMeOH.

[0214] In the installation represented at figure 15b, namely when the third stream 7 is directed in one or more solid oxide electrolyser cells 400 working in co-electrolysis mode (co-SOEC) and when the hydrogen-rich effluent 15 is fed to one or more compressors 700 prior to entering the reactor 100 of the methanol-generating unit, the process of methanol production is consuming at most 10.15 kWh / kgMeOH, preferably at most 10.10 kWh / kgMeOH.

[0215] Examples

[0216] The advantages of the present disclosure are illustrated by the following examples. However, it is understood that the disclosure is no means limited to the specific examples.

[0217] Table 1 indicates the results of the simulation of the energy consumption in relation with the methanol production in accordance with the different heat management methods that have been described in case where a solid oxide electrolyser cell working into electrolysis mode (SOEC) is combined with the methanol-generating unit. The energy consumption which is saved (8) is given with respect to a method wherein only the second stream 5 exiting the turbine at a pressure P2 of 0.5 MPa is directed to the separation unit to transfer its thermal energy to the temperature-regulating device 250, in the case where the methanol-generating unit is combined with a solid oxide electrolyser cell working in electrolysis mode (SOEC) (figure 2a). Table 1 : Results of simulation implying a heat management method comprising a solid oxide electrolyser cell working in electrolysis mode (SPEC)

[0218] As indicated, one of the best configurations in term of energy consumption ( / .e., figure 14a) is in the case where a step of transferring the thermal energy of the hydrogen-rich effluent 15 to a water stream 24 before the step of transferring the thermal energy of the oxygen outflow 21 to said water stream 24 so as the produce the additional stream 25 of steam generated at a pressure of 0.25 MPa ( / .e., a low-pressurized water stream). In addition, the thermal energy of the oxygen-containing effluent 13 is used to pre-heat the first stream 3 entering into the steam pressure-reducing device, generating thus the oxygen outflow 21. Then a step a transferring the thermal energy of the additional stream 25 of steam, supplemented by a back stream 30 of steam at a pressure of 0.25 MPa, to the temperature-regulating device 250 of the separation unit is carried out.

[0219] As indicated, a second best configuration in term of energy consumption ( / .e., figure 12a) is in the case where a step of transferring the thermal energy of the oxygen-containing effluent 13 to the first stream 3 recovered at step (c) so as to generate an oxygen outflow 21 followed by a step of providing a water stream 23 at a pressure of 0.50 MPa ( / .e., a medium-pressurized water stream). Then a step of transferring the thermal energy of the hydrogen-rich effluent 15 to the water stream 23 is carried out before a step of transferring the thermal energy of the oxygen outflow 21 , so as to generate an additional stream 25 at a pressure of 0.50 MPa. Finally, the step of regulating the thermal energy carried out in step (j) further comprises transferring the thermal energy of a first part 27 of the first additional stream to the temperatureregulating device 250 of the separation unit. An excess of steam, namely a second part 29 of the additional stream of steam is then fed to the one or more electrolyser cells 400 working in electrolysis mode.

[0220] Table 2 indicates the results of the simulation of the energy consumption in relation with the methanol production in accordance with the different heat management methods that have been described in case where a solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) is combined with the methanol-generating unit. The energy consumption which is saved (5) is given with respect to a method wherein only the second stream 5 exiting the turbine at a pressure P2 of 0.5 MPa is directed to the separation unit to transfer its thermal energy to the temperature-regulating device 250, in the case where the methanol-generating unit is combined with a solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) (figure 2b).

[0221] Table 2: Results of simulation implying a heat management method comprising a solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) As shown, replacing the solid oxide electrolyser cell working in electrolysis mode (SOEC) ( / .e., figure 12a) by a solid oxide electrolyser cell working in co-electrolysis mode (co-SOEC) ( / .e., figure 12b) where water stream 23 at a pressure of 0.50 MPa allows providing good results in term of energy consumption. However, the best results were obtained when, the water stream 24 is provided is at a pressure of 0.25 MPa ( / .e., a low-pressurized water stream), leading to the obtaining of an additional stream of steam 25 with a pressure of 0.25 MPa ( / .e., figure 14b).

Claims

Claims1. A heat management method in a methanol-generating unit, said method is characterized in that it comprises the following steps: a) providing a methanol-generating unit and a separation unit, wherein the separation unit is placed downstream of the methanol-generating unit and is in fluidic connection with it, wherein said separation unit comprises a temperatureregulating device (250), and wherein said methanol-generating unit comprises one or more reactors (100) each comprising a cooling device; b) operating said at least one reactor (100) under first operating conditions, said first operating conditions comprising at least regulating the thermal energy of said at least one reactor (100); wherein the step of regulating the thermal energy comprises adjusting the temperature of the cooling device with water (1); c) recovering from said cooling device, after said step of regulating the thermal energy, a first stream (3), said first stream (3) comprising steam at a pressure P1 ; d) decreasing the pressure of said first stream (3) so as to recover a second stream (5), said second stream (5) comprising steam at a pressure P2, wherein P2 < P1 ; e) providing one or more solid oxide electrolyser cells (400); f) feeding said one or more solid oxide electrolyser cells (400) with at least the second stream (5) recovered at step (d) or with a mixture comprising carbon dioxide and at least the second stream (5) recovered at step (d); g) working said one or more solid oxide electrolyser cells (400) under second operating conditions so as to generate a hydrogen-rich effluent (15) or a syngas effluent (19), said second operating conditions comprising at least electrical power and a temperature higher than 400°C; wherein the first operating conditions of step (b) comprise feeding said at least one reactor (100) with either a carbon oxides feedstock and the hydrogen-rich effluent (15) generated at step (g) or the syngas effluent (19) generated at step (g).

2. The heat management method according to claim 1 , characterized in that the pressure P2 of the second stream (5) is ranging between 0.31 MPa and 1.30 MPa and / or the first stream (3) is at a temperature T 1 comprised between 200°C and 325°C.

3. The heat management method according to claim 1 or 2, characterized in that the method further comprises the step of providing a complementary stream (11) of steam to said one or more solid oxide electrolyser cells (400) and / or to said temperatureregulating device (250) of the separation unit, said complementary stream (11) of steam being at a pressure ranging between 0.30 MPa and 1.29 MPa.

4. The heat management method according to any one of claims 1 to 3, characterized in that the second stream (5) comprising steam at a pressure P2 further comprises a condensate; and in that the method further comprises the step of separating the steam from said condensate so as to recover a third stream (7), said third stream (7) comprising steam at a pressure P3, wherein P3 is equal or inferior to P2; with preference, the step (f) of feeding said one or more solid oxide electrolyser cells (400) further comprises feeding said one or more solid oxide electrolyser cells (400) with the third stream (7) or with a mixture comprising carbon dioxide and the third stream (7).

5. The heat management method according to any one of claims 1 to 4, characterized in that the step (d) of decreasing the pressure of said first stream (3) further produces electrical energy; and in that said method further comprises the step of supplying said electrical energy to said one or more solid oxide electrolyser cells (400) so as to run said one or more solid oxide electrolyser cells (400) and / or in that the methanolgenerating unit provided at step (a) comprises one or more compressors, and the step (d) of decreasing the pressure of said first stream (3) further produces electrical energy and / or shaft work; and the method further comprises the step of supplying said electrical energy and / or shaft work to said one or more compressors so as to run the one or more compressors comprised within the methanol-generating unit.

6. The heat management method according to any one of claims 1 to 5, characterized in that the step (g) of working said one or more solid oxide electrolyser cells (400) under second operating conditions also generates an oxygen-containing effluent (13) and in that the method further comprises the following steps: h) providing a water stream (23, 24);i) transferring the thermal energy of at least the oxygen-containing effluent (13) to said water stream (23, 24) so as to produce an additional stream (25) of steam; and j) transferring the thermal energy of the additional stream (25) of steam to the temperature-regulating device of the separation unit.

7. The heat management method according to any one of claims 1 to 6, characterized in that the step (b) of operating said at least one reactor (100) generates a reactor effluent (150), and wherein the method further comprises the step of providing a water stream (23) and the step of transferring the thermal energy of said reactor effluent (150) to said water stream (23) so as to generate a third additional stream of steam (41), said third additional stream of steam (41) being then fed to said one or more solid oxide electrolyser cells (400); with preference, the water stream (23) provided to generate said third additional stream of steam (41) is at a pressure ranging between 0.30 MPa and 1.29 MPa.

8. The heat management method according to claim 6 or 7, characterized in that the step (j) of transferring the thermal energy of the additional stream (25) of steam to the temperature-regulating device (250) of the separation unit is a step of transferring the thermal energy of a first part (27) of said additional stream of steam; and wherein the method further comprises the step of feeding a second part (29) of said additional stream of steam to said one or more solid oxide electrolyser cells (400) during step (f); and / or, the method further comprises a step of transferring the thermal energy of either the hydrogen-rich effluent (15) or the syngas effluent (19) to the water stream (23, 24) before the step of transferring the thermal energy of at least the oxygen-containing effluent (13) to said water stream (23, 24) so as to produce the additional stream (25) of steam.

9. The heat management method according to any one of claims 1 to 8, characterized in that the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream (3) recovered at step (c).

10. The heat management method according to any one of claims 1 to 9, characterized in that the hydrogen-rich effluent (15) or the syngas effluent (19) is subjected to a pressure increase step before being directed to the reactor (100), said pressure increase stepgenerating heat, and that the method further comprises the step of providing a water stream (23) and the step of transferring the heat generated by the pressure increase step to said water stream (23) so as to generate a second additional stream of steam (39), said second additional stream of steam (39) being then fed to said one or more solid oxide electrolyser cells (400); with preference, said water stream (23) provided to generate said second additional stream of steam (39) is at a pressure ranging between 0.30 MPa and 1.29 MPa.

11. The heat management method according to any one of claims 6 to 10, characterized in that the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream (3) recovered at step (c) and in that said step of transferring the thermal energy further generates an oxygen outflow (21); wherein the water stream (23) provided at step (h) is at a pressure ranging between 0.30 MPa and 1.29 MPa, and wherein the additional stream (25) of steam produced at step (i) is generated at a pressure ranging between 0.30 MPa to 1.29 MPa by transferring the thermal energy of the oxygen outflow (21) to said water stream (23); and the step (j) of transferring the thermal energy of the additional stream (25) of steam to the temperature-regulating device (250) of the separation unit is a step of transferring the thermal energy of the additional stream (25) of steam at a pressure ranging between 0.30 MPa to 1.29 MPa to the temperature-regulating device (250) of the separation unit.

12. The heat management method according to claim 11 , characterized in that the step (j) of transferring the thermal energy of the additional stream (25) of steam to the temperature-regulating device (250) of the separation unit is a step of transferring the thermal energy of a first part (27) of said additional stream of steam; and wherein the method further comprises the step of feeding a second part (29) of said additional stream of steam to said one or more solid oxide electrolyser cells (400) during step (f).

13. The heat management method according to claim 11 or 12, characterized in that the method further comprises a step of transferring the thermal energy of either the hydrogen-rich effluent (15) or the syngas effluent (19) to the water stream (23) before the step of transferring the thermal energy of the oxygen outflow (21) to said water stream (23) so as to produce the additional stream (25) of steam at a pressure ranging between 0.30 MPa to 1.29 MPa.

14. The heat management method according to any one of claims 6 to 10, characterized in that the method further comprises the step of transferring the thermal energy of the oxygen-containing effluent generated at step (g) to the first stream (3) recovered at step (c) and in that said step of transferring the thermal energy further generates an oxygen outflow (21); wherein the water stream (24) provided at step (h) is at a pressure ranging below 0.30 MPa; and wherein the additional stream (25) of steam produced at step (i) is generated at a pressure below 0.30 MPa by transferring the thermal energy of the oxygen outflow (21) to said water stream (24); and the step (j) of transferring the thermal energy of the additional stream (25) of steam to the temperature-regulating device (250) of the separation unit is the step of transferring the thermal energy of the additional stream (25) of steam generated at a pressure below 0.30 MPa to the temperature-regulating device (250) of the separation unit; with preference, said step (j) is accompanied by a step of providing a backup stream (30) of steam at a pressure below 0.30 MPa to the temperature-regulating device (250) of the separation unit.

15. The heat management method according to claim 14, characterized in that the method further comprises a step of respectively transferring the thermal energy of the hydrogen-rich effluent (15) or the syngas effluent (19) to the water stream (24) before the step of transferring the thermal energy of at least the oxygen-containing effluent (13) to said water stream (24) so as to produce the additional stream (25) of steam at a pressure below 0.30 MPa.

16. An installation for producing methanol remarkable in that the installation comprising a methanol-generating unit and a separation unit, wherein said separation unit is placed downstream of the methanol-generating unit and is in fluidic connection with it, wherein the separation unit comprises a temperatureregulating device (250), and wherein the methanol-generating unit comprising one or more reactors (100), each reactor (100) comprising a cooling device; one or more solid oxide electrolyser cells (400), wherein said one or more solid oxide electrolyser cells (400) are placed downstream of said cooling device, and in fluidic connection with it; each of said one or more solid oxide electrolyser cells (400) comprising a hydrogen-output line to direct a hydrogen-rich effluent (15) or a syngas effluent (19) out of said solid oxide electrolyser cell (400); and wherein the installation further comprises a line fluidically connecting the hydrogen-output line to the one or more reactors (100) of the methanolgenerating unit;at least one steam pressure-reducing device, the steam pressure-reducing device being placed downstream of said cooling device and upstream of said one or more solid oxide electrolyser cells (400); a first line connecting fluidically the cooling device to the one or more steam pressure-reducing devices; a second line connecting fluidically the one or more steam pressure-reducing devices to the one or more solid oxide electrolyser cells (400), and wherein the one or more steam pressure-reducing devices comprise at least one steam pressure regulator; with preference, the one or more steam pressure regulators are one or more pressure control valves; and / or one steam pressure-reducing device is at least one turbine (300).

Images