CN113430534A

CN113430534A - Hydrogen production method, hydrogen production system, hydrogen production electrolyte circulation method and hydrogen production electrolyte circulation device

Info

Publication number: CN113430534A
Application number: CN202110700168.3A
Authority: CN
Inventors: 徐飞飞
Original assignee: Sungrow Power Supply Co Ltd
Current assignee: Sunshine Hydrogen Energy Technology Co Ltd
Priority date: 2021-06-23
Filing date: 2021-06-23
Publication date: 2021-09-24
Anticipated expiration: 2041-06-23
Also published as: CN113430534B

Abstract

The invention discloses a hydrogen production method, a hydrogen production system, a circulation method and a circulation device of hydrogen production electrolyte, wherein the circulation method comprises an oxygen side electrolyte circulation method and/or a hydrogen side electrolyte circulation method; the oxygen side electrolyte circulation method comprises the following steps: carrying out gas-liquid separation on a gas-liquid mixture discharged from the oxygen side of the electrolytic cell to obtain oxygen side separated electrolyte; carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte to obtain oxygen side pressure reduction separation electrolyte; boosting the oxygen side reduced pressure separation electrolyte and inputting the boosted oxygen side reduced pressure separation electrolyte into an electrolytic cell; the hydrogen side electrolyte circulation method comprises the following steps: carrying out gas-liquid separation on a gas-liquid mixture discharged from the hydrogen side of the electrolytic cell to obtain a hydrogen side separation electrolyte; carrying out pressure reduction gas-liquid separation on the hydrogen side separation electrolyte to obtain hydrogen side pressure reduction separation electrolyte; and boosting the pressure of the hydrogen side decompression separation electrolyte and inputting the hydrogen side decompression separation electrolyte into the electrolytic cell. The circulation method can improve the purity of hydrogen and oxygen obtained by hydrogen production through water electrolysis, and can also ensure higher system pressure.

Description

Hydrogen production method, hydrogen production system, hydrogen production electrolyte circulation method and hydrogen production electrolyte circulation device

Technical Field

The invention relates to the technical field of hydrogen production by water electrolysis, in particular to a hydrogen production method, a hydrogen production system, a circulation method of hydrogen production electrolyte and a circulation device.

Background

At present, in a hydrogen production process by water electrolysis, a hydrogen side gas-liquid mixture and an oxygen side gas-liquid mixture generated by electrolysis of an electrolysis bath respectively enter respective gas-liquid separators, and electrolytes separated by the gas-liquid separators are merged and then enter a heat exchanger for cooling, and then are returned to the electrolysis bath.

As the pressure of the whole hydrogen production system is high, the electrolyte contains hydrogen and oxygen, and the cooled electrolyte carries the hydrogen and the oxygen into the anode and cathode electrolysis chambers of the electrolysis cell, so that the hydrogen is mixed in the oxygen generated in the anode electrolysis chamber, the oxygen is mixed in the hydrogen generated in the cathode electrolysis chamber, and the purity of the obtained hydrogen is low.

In summary, how to improve the purity of hydrogen obtained by hydrogen production through water electrolysis is a problem to be solved urgently by those skilled in the art.

Disclosure of Invention

The invention aims to provide a circulation method of hydrogen production electrolyte, which is used for improving the purity of hydrogen obtained by electrolyzing water to produce hydrogen. Another object of the present invention is to provide a hydrogen production electrolyte circulation device, a hydrogen production method, and a hydrogen production system, wherein the hydrogen production method includes the above hydrogen production electrolyte circulation method, and the hydrogen production system includes the above hydrogen production electrolyte circulation device.

In order to achieve the above purpose, the invention provides the following technical scheme:

a circulation method of a hydrogen production electrolyte includes an oxygen side electrolyte circulation method and/or a hydrogen side electrolyte circulation method;

wherein the oxygen side electrolyte circulation method comprises the steps of: carrying out gas-liquid separation on a gas-liquid mixture discharged from the oxygen side of the electrolytic cell to obtain separated oxygen and separated electrolyte at the oxygen side; carrying out at least one pressure-reducing gas-liquid separation on the oxygen side separation electrolyte to obtain pressure-reducing separation oxygen and oxygen side pressure-reducing separation electrolyte; boosting the oxygen side reduced pressure separation electrolyte, and inputting the boosted oxygen side reduced pressure separation electrolyte into the electrolytic cell;

the hydrogen side electrolyte circulation method comprises the following steps: carrying out gas-liquid separation on a gas-liquid mixture discharged from the hydrogen side of the electrolytic cell to obtain separated hydrogen and a hydrogen side separated electrolyte; carrying out at least one pressure-reducing gas-liquid separation on the hydrogen side separation electrolyte to obtain pressure-reducing separation hydrogen and hydrogen side pressure-reducing separation electrolyte; and boosting the hydrogen side depressurization separation electrolyte, and inputting the boosted hydrogen side depressurization separation electrolyte into the electrolytic cell.

Optionally, the oxygen-side electrolyte circulation method further comprises the steps of: cooling the oxygen side reduced pressure separation electrolyte before or after the step of boosting the oxygen side reduced pressure separation electrolyte;

the hydrogen-side electrolyte circulation method further includes the steps of: cooling the hydrogen side de-pressurization separation electrolyte, the step of cooling the hydrogen side de-pressurization separation electrolyte being before or after the step of pressurizing the hydrogen side de-pressurization separation electrolyte.

Optionally, the same depressurization gas-liquid separation device is used for carrying out depressurization gas-liquid separation on the oxygen-side separation electrolyte and the hydrogen-side separation electrolyte;

or the oxygen side pressure reduction gas-liquid separation device is used for carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte, the hydrogen side pressure reduction gas-liquid separation device is used for carrying out pressure reduction gas-liquid separation on the hydrogen side separation electrolyte, and the oxygen side pressure reduction gas-liquid separation device and the hydrogen side pressure reduction gas-liquid separation device are not the same device.

Optionally, the same booster pump is used for boosting the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte;

or, an oxygen side booster pump is used for boosting the oxygen side pressure reduction separation electrolyte, a hydrogen side booster pump is used for boosting the hydrogen side pressure reduction separation electrolyte, and the oxygen side booster pump and the hydrogen side booster pump are not the same booster pump.

Optionally, in the oxygen side electrolyte circulation method, the pressure of the oxygen side separation electrolyte is reduced to 0 to 4.0MPa, and the pressure of the oxygen side reduced pressure separation electrolyte is increased to 0.5 to 4.0 MPa;

in the hydrogen side electrolyte circulation method, the pressure of the hydrogen side separation electrolyte is reduced to 0-4.0MPa, and the pressure of the hydrogen side reduced pressure separation electrolyte is increased to 0.5-4.0 MPa.

According to the circulation method of the hydrogen production electrolyte, the pressure reduction gas-liquid separation is carried out on the oxygen side separated electrolyte obtained by the gas-liquid separation, namely, the oxygen in the electrolyte is further separated by reducing the pressure, and the oxygen content of the electrolyte entering the electrolytic cell is reduced, so that the oxygen content mixed with the hydrogen generated by electrolysis in the cathode electrolytic chamber is reduced, and the purity of the hydrogen obtained by hydrogen production through water electrolysis is effectively improved; meanwhile, the oxygen side reduced pressure separation electrolyte obtained by reduced pressure gas-liquid separation is subjected to pressure rise, so that higher system pressure is ensured, the power consumption of gas in the storage and transportation process is reduced, the energy consumption is reduced, and the energy conservation is realized.

According to the circulation method of the hydrogen production electrolyte, the hydrogen side separation electrolyte obtained by gas-liquid separation is subjected to pressure reduction gas-liquid separation, namely, hydrogen in the electrolyte is further separated by reducing pressure, and the hydrogen content of the electrolyte entering an electrolytic cell is reduced, so that the hydrogen content mixed with oxygen generated by electrolysis in an anode electrolytic chamber is reduced, and the purity of the oxygen obtained by hydrogen production through water electrolysis is effectively improved; meanwhile, the hydrogen side depressurization separation electrolyte obtained by depressurization gas-liquid separation is subjected to pressure rise, so that higher system pressure is ensured, the power consumption of gas in the storage and transportation process is reduced, the energy consumption is reduced, and the energy conservation is realized.

Meanwhile, the circulation method of the hydrogen production electrolyte provided by the invention can improve the purity of hydrogen and oxygen obtained by electrolyzing water to produce hydrogen, reduce the operation load of the purification equipment, prolong the service life of the catalyst in the purification equipment and reduce the cost.

Based on the circulation method of the hydrogen production electrolyte, the invention also provides a hydrogen production method, which comprises any one of the circulation methods.

Based on the above-mentioned circulation method for hydrogen production electrolyte, the present invention also provides a circulation device for hydrogen production electrolyte, which is characterized by comprising: an oxygen-side electrolyte circulation device and/or a hydrogen-side electrolyte circulation device;

wherein the oxygen-side electrolyte circulating device includes: the oxygen side gas-liquid separation device is used for carrying out gas-liquid separation on a gas-liquid mixture discharged from the oxygen side of the electrolytic cell; at least one oxygen side pressure reduction gas-liquid separation device, which is used for carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte separated by the oxygen side gas-liquid separation device; the oxygen side boosting device is used for boosting the oxygen side reduced pressure separation electrolyte separated by the oxygen side reduced pressure gas-liquid separation device; an oxygen side delivery device for delivering the oxygen side reduced pressure separated electrolyte after pressure increase to the electrolytic cell;

the hydrogen-side electrolyte circulation device includes: the hydrogen side gas-liquid separation device is used for carrying out gas-liquid separation on a gas-liquid mixture discharged from the hydrogen side of the electrolytic cell; at least one hydrogen-side pressure-reducing gas-liquid separation device for performing pressure-reducing gas-liquid separation on the hydrogen-side separation electrolyte separated by the hydrogen-side gas-liquid separation device; the hydrogen side pressure boosting device is used for boosting the pressure of the hydrogen side pressure reduction separation electrolyte separated by the hydrogen side pressure reduction gas-liquid separation device; the hydrogen side conveying device is used for inputting the hydrogen side decompression separation electrolyte after being boosted into the electrolytic cell;

if the number of the oxygen side reduced pressure gas-liquid separation devices is at least two, any two oxygen side reduced pressure gas-liquid separation devices are connected in series; if the number of the hydrogen side pressure reduction gas-liquid separation devices is at least two, any two hydrogen side pressure reduction gas-liquid separation devices are connected in series.

Optionally, the oxygen-side electrolyte circulation device further comprises: an oxygen side cooling device for cooling the oxygen side reduced pressure separation electrolyte; wherein the oxygen-side cooling device is located upstream or downstream of the oxygen-side pressure-increasing device;

the hydrogen-side electrolyte circulation device further includes: the hydrogen side cooling device is used for cooling the hydrogen side decompression separation electrolyte; wherein the hydrogen-side cooling device is located upstream or downstream of the hydrogen-side pressure-increasing device.

Alternatively, the oxygen-side cooling device and the hydrogen-side cooling device are the same device.

Optionally, the oxygen side pressure boosting device and the oxygen side delivery device are the same booster pump;

and/or the hydrogen side booster device and the hydrogen side conveying device are the same booster pump;

and/or the oxygen side pressure reduction gas-liquid separation device comprises an oxygen side flash evaporator, and an oxygen side pressure reduction valve is arranged on an inlet pipe of the oxygen side flash evaporator;

and/or the hydrogen side pressure reduction gas-liquid separation device comprises a hydrogen side flash evaporator, and a hydrogen side pressure reduction valve is arranged on an inlet pipe of the hydrogen side flash evaporator.

Optionally, the hydrogen-side pressure-reducing gas-liquid separation device and the oxygen-side pressure-reducing gas-liquid separation device are the same device, or the hydrogen-side pressure-reducing gas-liquid separation device and the oxygen-side pressure-reducing gas-liquid separation device are not the same device.

Optionally, the hydrogen-side pressure boosting device and the oxygen-side pressure boosting device are the same device, or the hydrogen-side pressure boosting device and the oxygen-side pressure boosting device are not the same device.

Optionally, the oxygen-side electrolyte circulation device further comprises: an oxygen side controller for controlling the oxygen side pressure-reducing gas-liquid separation device to reduce the pressure of the oxygen side separated electrolyte to within a first oxygen side set pressure range and for controlling the oxygen side pressure-increasing device to increase the pressure of the oxygen side pressure-reducing separated electrolyte to within a second oxygen side set pressure range;

the hydrogen-side electrolyte circulation device further includes: and the hydrogen side controller is used for controlling the hydrogen side depressurization gas-liquid separation device to reduce the pressure of the hydrogen side separation electrolyte to be within a first hydrogen side set pressure range and controlling the hydrogen side pressure boosting device to increase the pressure of the hydrogen side depressurization separation electrolyte to be within a second hydrogen side set pressure range.

Optionally, the oxygen-side controller and the hydrogen-side controller are integrated.

Based on the above-mentioned circulation device for hydrogen production electrolyte, the invention also provides a hydrogen production system, which comprises the electrolyte circulation device, wherein the electrolyte circulation device is any one of the above-mentioned circulation devices.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a hydrogen production electrolyte circulation device according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a hydrogen production electrolyte circulation device provided in the second embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a hydrogen production electrolyte circulation device provided in the third embodiment of the present invention;

fig. 4 is a schematic structural diagram of a hydrogen production electrolyte circulation device according to a fourth embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The hydrogen production electrolyte circulation method provided by the embodiment of the invention comprises an oxygen side electrolyte circulation method and/or a hydrogen side electrolyte circulation method.

Specifically, the oxygen-side electrolyte circulation method includes the steps of:

s01) subjecting the gas-liquid mixture discharged from the oxygen side of the electrolytic cell to gas-liquid separation to obtain separated oxygen gas and an oxygen-side separated electrolyte:

it will be understood that the gas-liquid mixture discharged from the oxygen side of the electrolytic cell, i.e. the gas-liquid mixture discharged from the oxygen side outlet of the electrolytic cell, is a gas-liquid mixture of oxygen and the electrolyte. Oxygen is also present in the oxygen side separation electrolyte.

S02) carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte to obtain pressure reduction separation oxygen and oxygen side pressure reduction separation electrolyte:

optionally, a flash evaporator is adopted to perform pressure reduction gas-liquid separation on the oxygen side separation electrolyte, specifically, a pressure reducing valve on an inlet pipe of the flash evaporator is used for reducing pressure of the oxygen side separation electrolyte, and flash evaporation is realized in the flash evaporator through pressure reduction, so that gas-liquid separation is realized.

Through the decompression gas-liquid separation, oxygen in the electrolyte can be further discharged, and the purity of hydrogen is improved.

S03) boosting the oxygen side reduced pressure separation electrolyte:

the oxygen side reduced pressure separation electrolyte has a lower pressure due to the reduced pressure. In order to ensure higher system pressure and reduce the power consumption of gas in the process of storage and transportation, the oxygen side reduced pressure separation electrolyte is boosted, for example, a booster pump can be used for boosting the oxygen side reduced pressure separation electrolyte.

S04) feeding the oxygen side reduced pressure separated electrolyte after pressure increase into an electrolytic cell:

the oxygen-side reduced pressure separation electrolyte after being boosted can be input into the electrolytic cell by the optional transfer pump, and the oxygen-side reduced pressure separation electrolyte can be boosted by the booster pump, so that the oxygen-side reduced pressure separation electrolyte can be boosted by the booster pump and input into the electrolytic cell. Thus, the number of devices is reduced, and the cost is reduced; and moreover, the boosting pump is adopted to boost the oxygen side pressure reduction separation electrolyte, so that compared with the method of boosting gas by adopting a compressor, the energy consumption is reduced, the danger is also reduced, and the long-period stable operation of the whole hydrogen production process is convenient to ensure.

According to the circulation method of the hydrogen production electrolyte provided by the embodiment of the invention, the pressure reduction gas-liquid separation is carried out on the oxygen side separated electrolyte obtained by gas-liquid separation, namely, the oxygen in the electrolyte is further separated by reducing the pressure, so that the oxygen content of the electrolyte entering the electrolytic cell is reduced, the oxygen content mixed with the hydrogen generated by electrolysis in the cathode electrolytic chamber is reduced, and the purity of the hydrogen obtained by hydrogen production through water electrolysis is effectively improved; meanwhile, the oxygen side reduced pressure separation electrolyte obtained by reduced pressure gas-liquid separation is subjected to pressure rise, so that higher system pressure is ensured, the power consumption of gas in the storage and transportation process is reduced, the energy consumption is reduced, and the energy conservation is realized.

Meanwhile, the circulation method of the hydrogen production electrolyte provided by the embodiment of the invention improves the purity of hydrogen obtained by electrolyzing water to produce hydrogen, reduces the operation load of the purification equipment, prolongs the service life of the catalyst in the purification equipment, and reduces the hydrogen production cost.

In the above oxygen-side electrolyte circulation method, the number of times of the depressurization gas-liquid separation performed on the oxygen-side separation electrolyte may be one, or may be two or more. It is understood that the more times the depressurized gas-liquid separation is performed, the higher the purity of hydrogen gas is. In order to improve the purity of the hydrogen, the times of gas-liquid separation under reduced pressure can be selected to be more than two times. For example, the number of times of the depressurization gas-liquid separation is two, and the electrolyte obtained by the first depressurization gas-liquid separation is subjected to the second depressurization gas-liquid separation.

The electrolyte needs to be cooled before entering the electrolytic cell, and in order to optimize the scheme, the oxygen side electrolyte circulation method can be selected to further comprise the following steps: the step of cooling the oxygen-side reduced pressure separation electrolyte is performed before or after the step of S03.

Specifically, the step of cooling the oxygen-side reduced pressure separation electrolyte may be selected after the step of S03. Therefore, the reduction of heat exchange efficiency caused by gas overflow in the cooling process can be avoided, the energy consumption is reduced, and the stable and reliable physical property of the electrolyte entering the electrolytic cell is ensured; the condensate gas can be prevented from occurring in the cooling process of the electrolyte, and the condensate gas is prevented from entering the conveying device, so that the condensate gas is prevented from influencing the normal work of the conveying device; the recovery rate of oxygen in the electrolyte can be improved.

In the above-mentioned circulation method of hydrogen production electrolyte, the number of times of boosting the oxygen side pressure-reducing separation electrolyte may be one time, or may be two or more times, as long as the required pressure is ensured. In the practical application process, in order to ensure the stability, the step pressure can be selected, namely the step pressure of the oxygen side reduced pressure separation electrolyte is performed at least twice. For example, the oxygen-side pressure-drop separation electrolyte is subjected to pressure increase twice, that is, the oxygen-side pressure-drop separation electrolyte is subjected to pressure increase for the first time and then to pressure increase for the second time.

If the number of times of pressurizing the oxygen-side pressure-drop separation electrolyte is at least two times, the oxygen-side pressure-drop separation electrolyte may be optionally cooled before the pressurization, or the oxygen-side pressure-drop separation electrolyte may be optionally cooled between two adjacent times of pressurization. If the latter is selected, the above-mentioned method for circulating the hydrogen production electrolyte further comprises the following steps between two adjacent pressure increases: the oxygen side reduced pressure separated electrolyte is cooled.

It is understood that the number of times of cooling the oxygen side reduced pressure separation electrolyte is once. In the practical application process, the number of cooling times may be increased, which is not limited in this embodiment.

The hydrogen side electrolyte circulation method comprises the following steps:

s01') gas-liquid separating the gas-liquid mixture discharged from the hydrogen side of the electrolytic cell to obtain separated hydrogen gas and a hydrogen-side separated electrolyte:

it will be understood that the gas-liquid mixture discharged from the hydrogen side of the electrolytic cell, i.e. the gas-liquid mixture discharged from the hydrogen side outlet of the electrolytic cell, is a gas-liquid mixture of hydrogen gas and electrolyte. Hydrogen gas is also present in the hydrogen side separation electrolyte.

S02') performing pressure-reducing gas-liquid separation on the hydrogen-side separation electrolyte to obtain a pressure-reducing separation hydrogen gas and a hydrogen-side pressure-reducing separation electrolyte:

the hydrogen side separation electrolyte can be subjected to pressure reduction gas-liquid separation by selectively adopting a flash evaporator, specifically, the pressure reduction valve on the inlet pipe of the flash evaporator is used for reducing the pressure of the hydrogen side separation electrolyte, and flash evaporation is realized in the flash evaporator through pressure reduction, so that gas-liquid separation is realized.

Through the pressure reduction gas-liquid separation, the hydrogen in the electrolyte can be further discharged, and the oxygen purity is improved.

S03') increasing the pressure of the hydrogen-side depressurized separated electrolyte:

due to the depressurization, the pressure of the hydrogen side depressurization separation electrolyte is lower. In order to ensure higher system pressure and reduce the power consumption of gas in the storage and transportation processes, the hydrogen side depressurization separation electrolyte is boosted, for example, a booster pump can be used for boosting the hydrogen side depressurization separation electrolyte.

S04') feeding the hydrogen-side depressurized separated electrolyte after pressure increase into an electrolytic cell:

the hydrogen side reduced pressure separation electrolyte after being boosted can be input into the electrolytic cell by the selectable delivery pump, and the hydrogen side reduced pressure separation electrolyte can be boosted by the booster pump, so that the hydrogen side reduced pressure separation electrolyte can be boosted by the booster pump and input into the electrolytic cell. Thus, the number of devices is reduced, and the cost is reduced; and moreover, the pressure of the hydrogen side depressurization separation electrolyte is boosted by adopting the booster pump, compared with the pressure boosting of gas by adopting a compressor, the energy consumption is reduced, the danger is also reduced, and the long-period stable operation of the whole hydrogen production process is convenient to ensure.

In the hydrogen side electrolyte circulation method, the hydrogen side separated electrolyte obtained by gas-liquid separation is subjected to pressure reduction gas-liquid separation, namely, hydrogen in the electrolyte is further separated by reducing the pressure, and the hydrogen content of the electrolyte entering the electrolytic cell is reduced, so that the hydrogen content mixed with oxygen generated by electrolysis in the anode electrolytic chamber is reduced, and the purity of the oxygen obtained by hydrogen production through water electrolysis is effectively improved; meanwhile, the hydrogen side depressurization separation electrolyte obtained by depressurization gas-liquid separation is subjected to pressure rise, so that higher system pressure is ensured, the power consumption of gas in the storage and transportation process is reduced, the energy consumption is reduced, and the energy conservation is realized.

Meanwhile, the hydrogen side electrolyte circulation method improves the purity of oxygen obtained by hydrogen production through water electrolysis, reduces the operation load of the purification equipment, prolongs the service life of the catalyst in the purification equipment, and reduces the cost.

In the above circulation method of hydrogen production electrolyte, step S01 and step S01' may be performed simultaneously or sequentially; step S02 and step S02' may be performed simultaneously or sequentially; step S03 and step S03' may be performed simultaneously or sequentially; step S04 and step S04' may be performed simultaneously or sequentially, as long as normal operation is ensured.

In the above method for circulating the hydrogen side electrolyte, the number of times of the depressurization gas-liquid separation performed on the hydrogen side separated electrolyte may be one, or may be two or more. It is understood that the more times the depressurized gas-liquid separation is performed, the higher the purity of oxygen is. In order to improve the purity of the hydrogen, the times of gas-liquid separation under reduced pressure can be selected to be more than two times. For example, the number of times of the depressurization gas-liquid separation is two, and the electrolyte obtained by the first depressurization gas-liquid separation is subjected to the second depressurization gas-liquid separation.

The electrolyte needs to be cooled before entering the electrolytic cell, and the hydrogen side electrolyte circulation method can further comprise the following steps: cooling the hydrogen side depressurized separated electrolyte, wherein the step of cooling the hydrogen side depressurized separated electrolyte is before or after the step of S03'.

Specifically, the above step may be selected to cool the hydrogen side depressurization separation electrolyte after the above step S03'. Therefore, the reduction of heat exchange efficiency caused by gas overflow in the cooling process can be avoided, the energy consumption is reduced, and the stable and reliable physical property of the electrolyte entering the electrolytic cell is ensured; the condensate gas can be prevented from occurring in the cooling process of the electrolyte, and the condensate gas is prevented from entering the conveying device, so that the condensate gas is prevented from influencing the normal work of the conveying device; the recovery rate of oxygen in the electrolyte can be improved.

In the above method for circulating the hydrogen side electrolyte, the number of times of raising the pressure of the hydrogen side depressurization separation electrolyte may be one, or may be two or more, as long as the pressure is raised to a desired pressure. In the practical application process, in order to ensure the stability, the step pressure can be selected, namely the step pressure of the hydrogen side depressurization separation electrolyte is increased at least twice. For example, the pressure of the hydrogen-side depressurized separation electrolyte is increased twice, that is, the pressure of the hydrogen-side depressurized separation electrolyte is increased for the first time, and then the pressure is increased for the second time.

If the number of times of increasing the pressure of the hydrogen side depressurization separation electrolyte is at least two times, the hydrogen side depressurization separation electrolyte may be optionally cooled before increasing the pressure, or the hydrogen side depressurization separation electrolyte may be optionally cooled between two adjacent times of increasing the pressure. If the latter is selected, namely the hydrogen side electrolyte circulation method, the method further comprises the following steps between two adjacent pressure increases: and cooling the hydrogen side decompression separation electrolyte.

It is understood that the number of times the hydrogen side depressurized separation electrolyte is cooled is one. In the practical application process, the number of cooling times may be increased, which is not limited in this embodiment.

In the hydrogen side electrolyte circulation method, the depressurization gas-liquid separation frequency of the hydrogen side separation electrolyte can be selected to be one time, and the depressurization gas-liquid separation frequency of the oxygen side separation electrolyte is selected to be one time or more than two times; alternatively, the number of times of the depressurized gas-liquid separation of the hydrogen-side separation electrolyte may be at least two, and the number of times of the depressurized gas-liquid separation of the oxygen-side separation electrolyte may be one or more than two.

It is understood that the number of times of the depressurized gas-liquid separation of the hydrogen-side separation electrolyte and the number of times of the depressurized gas-liquid separation of the oxygen-side separation electrolyte may be the same or different.

In the above-described method for circulating a hydrogen production electrolyte, the same depressurization gas-liquid separation apparatus may be used to perform depressurization gas-liquid separation on the oxygen-side separation electrolyte and the hydrogen-side separation electrolyte, for example, the same flash evaporator may be used to perform depressurization gas-liquid separation on the oxygen-side separation electrolyte and the hydrogen-side separation electrolyte, and at this time, the oxygen-side separation electrolyte and the hydrogen-side separation electrolyte may be merged first and then enter the same flash evaporator. Thus, the device is reduced, and the cost is reduced.

Of course, the oxygen side pressure reduction gas-liquid separation device can be used for carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte, the hydrogen side pressure reduction gas-liquid separation device can be used for carrying out pressure reduction gas-liquid separation on the hydrogen side separation electrolyte, and the oxygen side pressure reduction gas-liquid separation device and the hydrogen side pressure reduction gas-liquid separation device are not the same device. Thus, the hydrogen purity and the oxygen purity are improved, although the cost is high.

In the above-described method for circulating a hydrogen production electrolyte, if the number of at least one of the oxygen-side pressure-reducing gas-liquid separation device and the hydrogen-side pressure-reducing gas-liquid separation device is two or more, another option exists. Specifically, if the number of the oxygen-side pressure-reducing gas-liquid separation devices is greater than that of the hydrogen-side pressure-reducing gas-liquid separation devices, one oxygen-side pressure-reducing gas-liquid separation device and one hydrogen-side pressure-reducing gas-liquid separation device can be selected to be the same device, and the other oxygen-side pressure-reducing gas-liquid separation devices and the other hydrogen-side pressure-reducing gas-liquid separation devices are not the same device; if the number of the oxygen side pressure reduction gas-liquid separation devices is smaller than that of the hydrogen side pressure reduction gas-liquid separation devices, one oxygen side pressure reduction gas-liquid separation device and one hydrogen side pressure reduction gas-liquid separation device can be selected to be the same device, and other hydrogen side pressure reduction gas-liquid separation devices and the oxygen side pressure reduction gas-liquid separation devices are not the same device; if the number of the oxygen side pressure reduction gas-liquid separation devices is equal to that of the hydrogen side pressure reduction gas-liquid separation devices, one oxygen side pressure reduction gas-liquid separation device and one hydrogen side pressure reduction gas-liquid separation device can be selected to be the same device, and other hydrogen side pressure reduction gas-liquid separation devices and other oxygen side pressure reduction gas-liquid separation devices are not the same device.

In the above circulation method for hydrogen production electrolyte, the same booster pump may be used to boost the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte, and at this time, the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte need to be merged first and then enter the booster pump. Thus, the device is reduced, and the cost is reduced.

Of course, it is also possible to use an oxygen-side booster pump to boost the oxygen-side reduced-pressure separation electrolyte and a hydrogen-side booster pump to boost the hydrogen-side reduced-pressure separation electrolyte, where the oxygen-side booster pump and the hydrogen-side booster pump are not the same booster pump. Thus, although the cost is high, the boosting efficiency is improved.

In the above method for circulating a hydrogen-producing electrolyte, if the number of at least one of the oxygen-side booster pumps and the hydrogen-side booster pumps is two or more, another option exists. Specifically, if the number of oxygen-side booster pumps is smaller than the number of hydrogen-side booster pumps, one oxygen-side booster pump and one hydrogen-side booster pump can be selected as the same device, and the other hydrogen-side booster pumps and the oxygen-side booster pumps are not the same device; if the number of the oxygen side booster pumps is larger than that of the hydrogen side booster pumps, one oxygen side booster pump and one hydrogen side booster pump can be selected as the same device, and other oxygen side booster pumps and hydrogen side booster pumps are not the same device; if the number of the oxygen-side booster pumps is equal to that of the hydrogen-side booster pumps, one oxygen-side booster pump and one hydrogen-side booster pump can be selected as the same device, and other oxygen-side booster pumps and other hydrogen-side booster pumps are not the same device.

In the above-mentioned method for circulating the hydrogen production electrolyte, the range to which the pressure of the electrolyte is reduced in the pressure reduction gas-liquid separation process and the range to which the pressure of the electrolyte is increased in the pressure increase process are selected according to actual needs, for example, set according to the pressure of the whole hydrogen production system. Specifically, in the selective depressurization gas-liquid separation, the pressure of the oxygen side separation electrolyte is depressurized to 0-4.0MPa, and the pressure of the oxygen side depressurization separation electrolyte is increased to 0.5-4.0 MPa; and/or, in the optional depressurization gas-liquid separation, depressurizing the pressure of the hydrogen side separation electrolyte to 0-4.0MPa, and raising the pressure of the hydrogen side depressurization separation electrolyte to 0.5-4.0 MPa.

When the pressure reduction gas-liquid separation frequency of the oxygen side separation electrolyte is more than two times, the pressure reduction is carried out in a grading way, and finally the pressure of the oxygen side separation electrolyte is reduced to 0-4.0 MPa; when the pressure reduction gas-liquid separation frequency of the hydrogen side separation electrolyte is more than two times, carrying out step pressure reduction, and finally reducing the pressure of the hydrogen side separation electrolyte to 0-4.0 MPa; when the pressure increase times of the oxygen side pressure reduction separation electrolyte is more than two times, carrying out graded pressure increase, and finally increasing the pressure of the oxygen side pressure reduction separation electrolyte to 0.5-4.0 Mpa; when the pressure increase times of the hydrogen side depressurization separation electrolyte is more than two times, the pressure increase is carried out in a grading way, and finally the pressure of the hydrogen side depressurization separation electrolyte is increased to 0.5-4.0 Mpa.

In practical applications, the above numerical ranges can be selected from other ranges, and are not limited to the above limitations.

To more specifically illustrate the recycling method of hydrogen production electrolyte provided by the embodiments of the present invention, four embodiments are provided below for specific description.

Implement one

The method for circulating the hydrogen production electrolyte provided by the first embodiment of the present invention includes an oxygen side electrolyte circulation method. Specifically, the circulation method of the hydrogen production electrolyte comprises the following steps:

s11) carrying out gas-liquid separation on the gas-liquid mixture discharged from the oxygen side of the electrolytic cell to obtain separated oxygen and separated electrolyte on the oxygen side;

s12) carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte to obtain pressure reduction separation oxygen and the oxygen side pressure reduction separation electrolyte;

s13) carrying out first pressure boosting on the oxygen side pressure reduction separation electrolyte;

s14) cooling the oxygen side reduced pressure separation electrolyte;

s15) second pressurizing the oxygen-side reduced-pressure separation electrolyte and feeding the pressurized oxygen-side reduced-pressure separation electrolyte to the electrolytic cell.

Carry out two

The second embodiment provides a method for circulating a hydrogen production electrolyte, which includes an oxygen side electrolyte circulation method and a hydrogen side electrolyte circulation method. Specifically, the circulation method of the hydrogen production electrolyte comprises the following steps:

s21) carrying out gas-liquid separation on the gas-liquid mixture discharged from the oxygen side of the electrolytic cell to obtain separated oxygen and separated electrolyte on the oxygen side; carrying out gas-liquid separation on a gas-liquid mixture discharged from the hydrogen side of the electrolytic cell to obtain separated hydrogen and a hydrogen side separated electrolyte;

s22) merging the oxygen side separation electrolyte and the hydrogen side separation electrolyte to form a merged electrolyte, and performing pressure-reducing gas-liquid separation on the merged electrolyte to obtain a pressure-reducing separation gas and a pressure-reducing separation electrolyte;

s23) cooling the electrolyte subjected to decompression and separation;

s24) the pressure of the electrolyte is increased and the electrolyte is input into the electrolytic bath.

Implementation III

The method for circulating the hydrogen production electrolyte provided by the third embodiment of the present invention includes an oxygen side electrolyte circulation method and a hydrogen side electrolyte circulation method. Specifically, the circulation method of the hydrogen production electrolyte comprises the following steps:

s31) carrying out gas-liquid separation on the gas-liquid mixture discharged from the oxygen side of the electrolytic cell to obtain separated oxygen and separated electrolyte on the oxygen side; carrying out gas-liquid separation on a gas-liquid mixture discharged from the hydrogen side of the electrolytic cell to obtain separated hydrogen and a hydrogen side separated electrolyte;

s32) carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte to obtain pressure reduction separation oxygen and the oxygen side pressure reduction separation electrolyte; carrying out pressure reduction gas-liquid separation on the hydrogen side separation electrolyte to obtain pressure reduction separation hydrogen and hydrogen side pressure reduction separation electrolyte;

s33) merging the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte to form a merged electrolyte, and cooling the merged electrolyte;

s34) pressurizing the combined electrolytic solution and feeding the pressurized combined electrolytic solution to the electrolytic cell.

Practice four

The hydrogen production electrolyte circulation method provided by the fourth embodiment includes an oxygen side electrolyte circulation method and a hydrogen side electrolyte circulation method. Specifically, the circulation method of the hydrogen production electrolyte comprises the following steps:

s41) carrying out gas-liquid separation on the gas-liquid mixture discharged from the oxygen side of the electrolytic cell to obtain separated oxygen and separated electrolyte on the oxygen side; carrying out gas-liquid separation on a gas-liquid mixture discharged from the hydrogen side of the electrolytic cell to obtain separated hydrogen and a hydrogen side separated electrolyte;

s42) merging the oxygen side separation electrolyte and the hydrogen side separation electrolyte to form a merged electrolyte, and performing first pressure-reducing gas-liquid separation on the merged electrolyte to obtain first pressure-reducing separation gas and first pressure-reducing separation electrolyte;

s43) carrying out second pressure-reducing gas-liquid separation on the first pressure-reducing separated electrolyte to obtain second pressure-reducing separated gas and second pressure-reducing separated electrolyte;

s44) cooling the electrolyte obtained by the second decompression separation;

s45) raising the pressure of the second depressurized separated electrolyte and feeding the second depressurized separated electrolyte after raising the pressure into the electrolytic cell.

Based on the circulation method of the hydrogen production electrolyte provided by the above embodiment, the embodiment of the invention also provides a hydrogen production method, which comprises the circulation method of the hydrogen production electrolyte provided by the above embodiment.

Since the hydrogen production electrolyte circulation method provided by the embodiment has the technical effects, and the hydrogen production method comprises the hydrogen production electrolyte circulation method, the hydrogen production method also has corresponding technical effects, and details are not repeated herein.

Based on the hydrogen production electrolyte circulation method provided by the above embodiment, the embodiment of the present invention further provides a hydrogen production electrolyte circulation device, which includes: an oxygen-side electrolyte circulation device and/or a hydrogen-side electrolyte circulation device.

Specifically, the oxygen-side electrolyte circulation device includes: an oxygen side gas-liquid separation device, an oxygen side reduced pressure gas-liquid separation device, an oxygen side pressure boosting device, and an oxygen side delivery device; the oxygen side gas-liquid separation device is used for carrying out gas-liquid separation on a gas-liquid mixture discharged from the oxygen side of the electrolytic cell; the oxygen side pressure reduction gas-liquid separation device is used for carrying out pressure reduction gas-liquid separation on the oxygen side separation electrolyte separated by the oxygen side gas-liquid separation device; the oxygen side boosting device is used for boosting the oxygen side voltage reduction separation electrolyte separated by the oxygen side voltage reduction gas-liquid separation device; the oxygen side conveying device is used for conveying the oxygen side reduced pressure separation electrolyte after being boosted into the electrolytic cell.

The gas-liquid mixture discharged from the oxygen side of the electrolytic cell, that is, the gas-liquid mixture discharged from the oxygen side outlet of the electrolytic cell, is a gas-liquid mixture of oxygen gas and the electrolytic solution. Oxygen gas is also present in the oxygen side separation electrolyte, and therefore, decompression gas-liquid separation is also required to improve the purity.

The specific type of the oxygen-side pressure-reducing separation device is selected according to actual needs, and for example, the oxygen-side pressure-reducing separation device comprises an oxygen-side flash evaporator, an oxygen-side pressure-reducing valve is arranged in an inlet pipe of the oxygen-side flash evaporator, the oxygen-side pressure-reducing valve reduces the pressure of the oxygen-side separated electrolyte, and flash evaporation is realized in the flash evaporator, so that gas-liquid separation is realized. Therefore, by the pressure reduction gas-liquid separation, oxygen in the electrolyte can be further discharged, and the purity of hydrogen is improved.

The oxygen-side pressure-drop separation device may be one, or two or more than two oxygen-side pressure-drop separation devices may be connected in series, and the number of the oxygen-side pressure-drop separation devices is selected according to the required hydrogen purity, which is not limited in this embodiment.

The oxygen side reduced pressure separation electrolyte has a lower pressure due to the reduced pressure. In order to ensure a higher system pressure and reduce the power consumption of the gas during storage and transportation, the oxygen side pressure boosting device boosts the pressure of the oxygen side pressure-reducing separation electrolyte, for example, the oxygen side pressure boosting device may be an oxygen side pressure boosting pump, which is not limited in this embodiment. The oxygen side booster pump is adopted to boost the oxygen side pressure reduction separation electrolyte, compared with a compressor for boosting gas, the energy consumption is reduced, the danger is also reduced, and the long-period stable operation of the whole hydrogen production process is convenient to guarantee.

In the oxygen side electrolyte circulating device, the oxygen side pressure reduction separation device is used for carrying out pressure reduction gas-liquid separation on the oxygen side separated electrolyte obtained by gas-liquid separation, namely, oxygen in the electrolyte is further separated by reducing pressure, and the oxygen content of the electrolyte entering the electrolytic cell is reduced, so that the oxygen content mixed with hydrogen generated by electrolysis in the cathode electrolytic chamber is reduced, and the purity of the hydrogen obtained by hydrogen production through water electrolysis is effectively improved; meanwhile, the oxygen side pressure reduction separation electrolyte obtained by the pressure reduction gas-liquid separation is subjected to pressure reduction through the oxygen side pressure reduction device, so that higher system pressure is ensured, the power consumption of gas in the storage and transportation process is reduced, the energy consumption is reduced, and the energy conservation is realized.

Meanwhile, in the oxygen side electrolyte circulating device, the purity of the hydrogen obtained by electrolyzing water to prepare hydrogen is improved, the operation load of the purifying equipment is reduced, the service life of the catalyst in the purifying equipment is prolonged, and the hydrogen preparation cost is reduced.

The electrolyte needs to be cooled before entering the electrolytic cell, and therefore, the oxygen side electrolyte circulating device further comprises an oxygen side cooling device for cooling the oxygen side reduced pressure separation electrolyte; wherein the oxygen-side cooling device is located upstream or downstream of the oxygen-side pressure-increasing device.

It will be appreciated that the oxygen side cooling means described above is located downstream of the oxygen side pressure drop separation means.

Specifically, the oxygen side cooling device can be selected to be positioned at the downstream of the oxygen side boosting device, so that the reduction of heat exchange efficiency caused by gas overflow in the cooling process can be avoided, the energy consumption is reduced, and the stability and reliability of the physical property of the electrolyte entering the electrolytic cell are ensured; the condensate gas can be prevented from occurring in the cooling process of the electrolyte, and the condensate gas is prevented from entering the conveying device, so that the condensate gas is prevented from influencing the normal work of the conveying device; the recovery rate of oxygen in the electrolyte can be improved.

The number of the oxygen-side pressure-increasing devices may be one or two or more, as long as the required pressure is increased. In the practical application process, in order to ensure the stability, the step-up pressure can be selected, namely, at least two oxygen-side pressure-increasing devices are sequentially arranged in series. For example, there are two oxygen-side pressure increasing devices, namely a first oxygen-side pressure increasing device and a second oxygen-side pressure increasing device, and the oxygen-side pressure-reduced separated electrolyte sequentially passes through the first oxygen-side pressure increasing device and the second oxygen-side pressure increasing device.

If at least two oxygen-side pressure increasing devices are provided in series, the oxygen-side cooling device may be located between the two oxygen-side pressure increasing devices.

It is understood that the oxygen-side cooling device is one. In practical applications, two or more oxygen-side cooling devices may be selected, which is not limited in this embodiment.

The oxygen side transport device may be a pump, and if the oxygen side pressure increasing device is an oxygen side pressure increasing pump, it is selected that the oxygen side transport device and the oxygen side pressure increasing device are the same device, that is, the oxygen side transport device and the oxygen side pressure increasing device are the same pressure increasing pump. Thus, the number of devices is reduced, and the cost is reduced.

The hydrogen-side electrolyte circulation device includes: a hydrogen-side gas-liquid separation device, a hydrogen-side depressurization gas-liquid separation device, a hydrogen-side pressure boosting device and a hydrogen-side conveying device; the hydrogen side gas-liquid separation device is used for carrying out gas-liquid separation on a gas-liquid mixture discharged from the hydrogen side of the electrolytic cell; the hydrogen side depressurization gas-liquid separation device is used for carrying out depressurization gas-liquid separation on the hydrogen side separation electrolyte separated by the hydrogen side gas-liquid separation device; the hydrogen side pressure boosting device is used for boosting the pressure of the hydrogen side pressure reduction separation electrolyte separated by the hydrogen side pressure reduction gas-liquid separation device; the hydrogen side conveying device is used for conveying the hydrogen side decompression separation electrolyte after pressure rise into the electrolytic cell.

It will be understood that the gas-liquid mixture discharged from the hydrogen side of the electrolytic cell, i.e. the gas-liquid mixture discharged from the hydrogen side outlet of the electrolytic cell, is a gas-liquid mixture of hydrogen gas and electrolyte. Hydrogen gas is also present in the hydrogen side separation electrolyte, and therefore, decompression gas-liquid separation is required to improve the purity.

The specific type of the hydrogen side pressure reduction separation device is selected according to actual needs. Specifically, the hydrogen side pressure reduction separation device may be selected to include a hydrogen side flash evaporator, and a hydrogen side pressure reduction valve is provided in an inlet pipe of the hydrogen side flash evaporator. The hydrogen side pressure reducing valve reduces the pressure of the hydrogen side separation electrolyte, and flash evaporation is realized in the hydrogen side flash evaporator through pressure reduction, so that gas-liquid separation is realized. Therefore, hydrogen in the electrolyte can be further discharged through pressure reduction gas-liquid separation, and the oxygen purity is improved.

The hydrogen side pressure reduction separation device may be one, or two or more hydrogen side pressure reduction separation devices connected in series, and is selected according to the required oxygen purity, which is not limited in this embodiment.

Due to the depressurization, the pressure of the hydrogen side depressurization separation electrolyte is lower. In order to ensure higher system pressure and reduce the power consumption of gas in the storage and transportation processes, the hydrogen side boosting device boosts the pressure of the hydrogen side depressurization separation electrolyte, and for the convenience of boosting, the hydrogen side boosting device is a hydrogen side boosting pump. Compared with a compressor for boosting the pressure of the gas, the energy consumption and the danger are reduced, and the long-period stable operation of the whole hydrogen production process is convenient to guarantee.

In the hydrogen side electrolyte circulating device, the hydrogen side pressure reduction separation device is used for carrying out pressure reduction gas-liquid separation on the hydrogen side separation electrolyte obtained by gas-liquid separation, namely, hydrogen in the electrolyte is further separated by reducing the pressure, and the hydrogen content of the electrolyte entering the electrolytic cell is reduced, so that the hydrogen content mixed with oxygen generated by electrolysis in the anode electrolytic chamber is reduced, and the purity of the oxygen obtained by hydrogen production through water electrolysis is effectively improved; meanwhile, the hydrogen side pressure reduction separation electrolyte obtained by pressure reduction gas-liquid separation is subjected to pressure reduction through the hydrogen side pressure increasing device, so that higher system pressure is ensured, the power consumption of gas in the storage and transportation process is reduced, the energy consumption is reduced, and the energy conservation is realized.

Meanwhile, the hydrogen side electrolyte circulating device improves the purity of oxygen obtained by hydrogen production through water electrolysis, reduces the operation load of the purifying equipment, prolongs the service life of the catalyst in the purifying equipment, and reduces the cost.

The electrolyte needs to be cooled before entering the electrolytic cell, so the hydrogen side electrolyte circulating device further comprises a hydrogen side cooling device, and the hydrogen side cooling device is used for cooling the hydrogen side decompression separation electrolyte; wherein the hydrogen-side cooling device is located upstream or downstream of the hydrogen-side pressure-increasing device.

Specifically, the hydrogen-side cooling device may be selected to be located downstream of the hydrogen-side pressure increasing device. Therefore, the reduction of heat exchange efficiency caused by gas overflow in the cooling process can be avoided, the energy consumption is reduced, and the stable and reliable physical property of the electrolyte entering the electrolytic cell is ensured; the condensate gas can be prevented from occurring in the cooling process of the electrolyte, and the condensate gas is prevented from entering the conveying device, so that the condensate gas is prevented from influencing the normal work of the conveying device; the recovery rate of oxygen in the electrolyte can be improved.

The hydrogen side pressure raising device may be one or two or more, as long as the required pressure is raised. In the practical application process, in order to ensure the stability, the step-up pressure can be selected, namely, at least two hydrogen-side pressure-increasing devices are sequentially arranged in series. For example, the number of the hydrogen-side pressure increasing devices is two, and the two hydrogen-side pressure increasing devices are respectively a first hydrogen-side pressure increasing device and a second hydrogen-side pressure increasing device, and the hydrogen-side pressure-reducing separation electrolyte sequentially passes through the first hydrogen-side pressure increasing device and the second hydrogen-side pressure increasing device.

If at least two hydrogen-side pressure increasing devices are provided in series, the hydrogen-side cooling device may be located between the two hydrogen-side pressure increasing devices.

It is understood that the hydrogen-side cooling device described above is one. In practical applications, two or more hydrogen-side cooling devices may be selected, which is not limited in this embodiment.

The hydrogen-side transport device may be a pump, and if the hydrogen-side pressure boosting device is a hydrogen-side pressure boosting pump, the hydrogen-side transport device and the hydrogen-side pressure boosting device may be selected to be the same device, that is, the hydrogen-side transport device and the hydrogen-side pressure boosting device may be the same pressure boosting pump. Thus, the number of devices is reduced, and the cost is reduced.

In the above-mentioned hydrogen production electrolyte circulation device, the hydrogen side depressurization gas-liquid separation device and the oxygen side depressurization gas-liquid separation device may be selected as the same device, that is, the same device is used to perform depressurization gas-liquid separation on the oxygen side separation electrolyte and the hydrogen side separation electrolyte, for example, the same flash evaporator is used to perform depressurization gas-liquid separation on the oxygen side separation electrolyte and the hydrogen side separation electrolyte, and at this time, the oxygen side separation electrolyte and the hydrogen side separation electrolyte are firstly merged and then enter the same flash evaporator. Thus, the device is reduced, and the cost is reduced.

Of course, it is also possible to select a different device for the hydrogen-side pressure-reducing gas-liquid separation device and the oxygen-side pressure-reducing gas-liquid separation device, that is, to perform pressure-reducing gas-liquid separation on the oxygen-side separated electrolyte alone and pressure-reducing gas-liquid separation on the hydrogen-side separated electrolyte alone. Thus, the hydrogen purity and the oxygen purity are improved, although the cost is high.

In the above-described hydrogen production electrolyte circulation device, if the number of at least one of the oxygen-side pressure-reducing gas-liquid separation device and the hydrogen-side pressure-reducing gas-liquid separation device is two or more, another option exists. Specifically, if the number of the oxygen-side pressure-reducing gas-liquid separation devices is greater than that of the hydrogen-side pressure-reducing gas-liquid separation devices, one oxygen-side pressure-reducing gas-liquid separation device and one hydrogen-side pressure-reducing gas-liquid separation device can be selected to be the same device, and the other oxygen-side pressure-reducing gas-liquid separation devices and the other hydrogen-side pressure-reducing gas-liquid separation devices are not the same device; if the number of the oxygen side pressure reduction gas-liquid separation devices is smaller than that of the hydrogen side pressure reduction gas-liquid separation devices, one oxygen side pressure reduction gas-liquid separation device and one hydrogen side pressure reduction gas-liquid separation device can be selected to be the same device, and other hydrogen side pressure reduction gas-liquid separation devices and the oxygen side pressure reduction gas-liquid separation devices are not the same device; if the number of the oxygen side pressure reduction gas-liquid separation devices is equal to that of the hydrogen side pressure reduction gas-liquid separation devices, one oxygen side pressure reduction gas-liquid separation device and one hydrogen side pressure reduction gas-liquid separation device can be selected to be the same device, and other hydrogen side pressure reduction gas-liquid separation devices and other oxygen side pressure reduction gas-liquid separation devices are not the same device.

In the above-mentioned hydrogen production electrolyte circulation device, the hydrogen side pressure increasing device and the oxygen side pressure increasing device may be selected to be the same device, that is, the same device is used to increase the pressure of the oxygen side pressure reducing separation electrolyte and the hydrogen side pressure reducing separation electrolyte. For example, the same booster pump is used to boost the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte, and in this case, the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte need to be merged before entering the booster pump. Thus, the device is reduced, and the cost is reduced.

Of course, it is also possible to select a device other than the hydrogen-side pressure increasing device and the oxygen-side pressure increasing device, that is, to increase the pressure of the oxygen-side pressure-dropping separation electrolyte alone and to increase the pressure of the hydrogen-side pressure-dropping separation electrolyte alone. Thus, although the cost is high, the boosting efficiency is improved.

In the above-described hydrogen production electrolyte circulation device, if the number of at least one of the oxygen-side pressure increasing devices and the hydrogen-side pressure increasing devices is two or more, another option exists. Specifically, if the number of the oxygen-side pressure boosting devices is smaller than that of the hydrogen-side pressure boosting devices, one oxygen-side pressure boosting device and one hydrogen-side pressure boosting device can be selected to be the same device, and the other hydrogen-side pressure boosting devices and the oxygen-side pressure boosting devices are not the same device; if the number of the oxygen side boosting devices is larger than that of the hydrogen side boosting devices, one oxygen side boosting device and one hydrogen side boosting device can be selected to be the same device, and other oxygen side boosting devices and hydrogen side boosting devices are not the same device; if the number of the oxygen-side pressure boosting devices and the number of the hydrogen-side pressure boosting devices are equal, one oxygen-side pressure boosting device and one hydrogen-side pressure boosting device can be selected to be the same device, and the other oxygen-side pressure boosting devices and the other hydrogen-side pressure boosting devices are not the same device.

In the above hydrogen production electrolyte circulation device, the hydrogen side cooling device and the oxygen side cooling device may be selected to be the same cooling device, that is, the same cooling device is used to cool the hydrogen side depressurization separation electrolyte and the oxygen side depressurization separation electrolyte. At this time, the hydrogen-side pressure-reducing separation electrolyte and the oxygen-side pressure-reducing separation electrolyte are merged and then enter the cooling device. Of course, it is also possible to cool the hydrogen-side depressurized separation electrolyte alone and to cool the oxygen-side depressurized separation electrolyte alone.

In the above hydrogen production electrolyte circulation device, one hydrogen side pressure reduction gas-liquid separation device may be selected, and at least two oxygen side pressure reduction gas-liquid separation devices are connected in series in sequence or one oxygen side pressure reduction gas-liquid separation device is selected; or at least two hydrogen side pressure reduction gas-liquid separation devices are sequentially connected in series, and at least two oxygen side pressure reduction gas-liquid separation devices are sequentially connected in series or one oxygen side pressure reduction gas-liquid separation device is arranged.

The number of the hydrogen-side pressure-reduced gas-liquid separation device and the number of the oxygen-side pressure-reduced gas-liquid separation device may be the same or different.

In order to facilitate control of the pressure reduction and the pressure increase, the oxygen-side electrolyte circulation device further includes an oxygen-side controller for controlling the oxygen-side pressure reduction gas-liquid separation device to reduce the pressure of the oxygen-side hydrogen-side separation electrolyte to within a first oxygen-side set pressure range and for controlling the oxygen-side pressure increase device to increase the pressure of the oxygen-side pressure reduction separation electrolyte to within a second oxygen-side set pressure range.

Accordingly, the above hydrogen-side electrolyte circulation device further includes a hydrogen-side controller for controlling the hydrogen-side pressure-reducing gas-liquid separation device to reduce the pressure of the hydrogen-side separation electrolyte to within a first hydrogen-side set pressure range, and for controlling the hydrogen-side pressure-increasing device to increase the pressure of the hydrogen-side pressure-reducing separation electrolyte to within a second hydrogen-side set pressure range.

If the number of the oxygen side pressure reduction gas-liquid separation devices is more than two, the pressure is reduced in a grading manner, and finally the pressure is reduced to be within a first oxygen side set pressure range; if the number of the hydrogen side depressurization gas-liquid separation devices is more than two, carrying out step depressurization, and finally reducing the pressure to be within a first hydrogen side set pressure range; if the number of the oxygen side pressure boosting devices is more than two, step-by-step pressure boosting is carried out, and finally the pressure is boosted to be within a second oxygen side set pressure range; if the number of the hydrogen-side pressure boosting devices is more than two, the pressure is boosted in a grading manner, and finally the pressure is boosted to be within the second hydrogen-side set pressure range.

The specific numerical ranges of the first oxygen side set pressure range, the second oxygen side set pressure range, the first hydrogen side set pressure range, and the second hydrogen side set pressure range are selected according to actual needs, and the present embodiment does not limit the ranges.

Alternatively, the first oxygen side set pressure range and the first hydrogen side set pressure range may be each 0 to 4.0MPa, and the second oxygen side set pressure range and the second hydrogen side set pressure range may be each 0.5 to 4.0 MPa.

In order to simplify the structure, if the hydrogen production electrolyte circulation device comprises the oxygen side electrolyte circulation device and the hydrogen side electrolyte circulation device, the oxygen side controller and the hydrogen side controller can be selected to be integrated, so that the number of parts is reduced, and the compactness is improved. Of course, the oxygen-side controller and the hydrogen-side controller may be selected to be separate structures, and are not limited to the above embodiments.

To more specifically illustrate the hydrogen-producing electrolyte circulation device provided in this example, four examples are provided below.

Example one

As shown in fig. 1, the hydrogen production electrolyte circulation device provided in the first embodiment includes an oxygen-side electrolyte circulation device. Specifically, the above-mentioned circulation device for hydrogen production electrolyte comprises: a hydrogen-side gas-liquid separation device 17, an oxygen-side gas-liquid separation device 14, an oxygen-side depressurized gas-liquid separation device, an oxygen-side pressure boosting device, an oxygen-side transport device, an oxygen-side cooling device 110, and a controller.

Specifically, the number of the oxygen-side pressure increasing devices is two, and the two oxygen-side pressure increasing devices are respectively a first oxygen-side pressure increasing device and a second oxygen-side pressure increasing device; the first oxygen side pressure raising means is located upstream of the oxygen side cooling means 110, and the second oxygen side pressure raising means is located downstream of the oxygen side cooling means 110. In the circulation process, the first oxygen side pressure boosting device is used for boosting and conveying the oxygen side pressure-reduced separated electrolyte separated by the oxygen side pressure-reduced gas-liquid separation device, the oxygen side cooling device 110 is used for cooling the oxygen side pressure-reduced separated electrolyte passing through the first oxygen side pressure boosting device and also used for cooling the hydrogen side separated electrolyte separated by the hydrogen side gas-liquid separation device 17, and the second oxygen side pressure boosting device is used for boosting and conveying the electrolyte passing through the oxygen side cooling device 110 to the electrolytic cell 11.

The oxygen side pressure increasing device and the oxygen side transport device are the same device, and for the convenience of pressure increase, the oxygen side pressure increasing device and the oxygen side transport device are the same oxygen side pressure increasing pump. In this case, the first oxygen side pressure increasing device is the first oxygen side pressure increasing pump 116, and the second oxygen side pressure increasing device is the second oxygen side pressure increasing pump 113. It is understood that the number of the oxygen-side pressure boosting devices and the number of the oxygen-side transport devices are equal at this time.

The oxygen side pressure reduction gas-liquid separation device includes an oxygen side flash evaporator 115 and an oxygen side pressure reduction valve 121 provided in an inlet pipe of the oxygen side flash evaporator 115. The controller controls the oxygen-side pressure reducing valve 121 to reduce the pressure of the oxygen-side separation electrolyte to within a first oxygen-side set pressure range, the first oxygen-side pressure-increasing pump 116 to increase the pressure of the oxygen-side pressure-reduction separation electrolyte to within a third oxygen-side set pressure range, and the second oxygen-side pressure-increasing pump 113 to increase the pressure of the oxygen-side pressure-reduction separation electrolyte to within a fourth oxygen-side set pressure range. And the set of the third oxygen side set pressure range and the fourth oxygen side set pressure range is the second oxygen side set pressure range.

Specific ranges of the first oxygen side set pressure range, the second oxygen side set pressure range, the third oxygen side set pressure range, and the fourth oxygen side set pressure range are selected according to actual needs, for example, the specific ranges mentioned above can be referred to, and the present embodiment does not limit the ranges.

In the hydrogen-producing electrolyte circulation device according to the first embodiment, the electrolytic cell 11 has the hydrogen-side outlet 1101, the oxygen-side outlet 1102, and the electrolyte inlet 1103, the oxygen-side gas-liquid separation device 14 has the oxygen-side separation inlet 1401, the oxygen-side gas-phase outlet 1402, and the oxygen-side liquid-phase outlet 1403, the hydrogen-side gas-liquid separation device 17 has the hydrogen-side separation inlet 1701, the hydrogen-side gas-phase outlet 1702, and the hydrogen-side liquid-phase outlet 1703, the oxygen-side flash evaporator 115 has the oxygen-side flash evaporation inlet 11501, the oxygen-side flash evaporation vapor phase outlet 11502, and the oxygen-side flash evaporation liquid-phase outlet 11503, and the oxygen-side cooling device 110 has an inlet, an outlet, a cooling medium inlet, and a cooling medium outlet.

In order to achieve the communication of the respective components, the oxygen-side separation inlet 1401 and the oxygen-side outlet 1102 are communicated through a first pipeline 12, the oxygen-side gas phase outlet 1402 is communicated with a second pipeline 15, the second pipeline 15 is provided with a first valve 16, the oxygen-side liquid phase outlet 1403 is communicated with the oxygen-side flash inlet 11501 through a third pipeline 120, in this case, the third pipeline 120 is the inlet pipe of the oxygen-side flash evaporator 115, a pressure reducing valve 121 is provided on the third pipeline 120, the oxygen-side flash vapor phase outlet 11502 is communicated with a fourth pipeline 119, the fourth pipeline 119 is provided with a second valve 118, the fourth pipeline 119 is communicated with the second pipeline 15, the oxygen-side flash vapor phase outlet 11503 is communicated with the inlet of the oxygen-side cooling device 110 through a fifth pipeline 111, the first oxygen-side booster pump 116 is connected in series to the fifth pipeline 111, the fifth pipeline 111 is provided with the third valve 117, and the third valve 117 is located at the outlet side of the first oxygen-side flash vapor phase outlet 116, the oxygen-side cooling device 10 is communicated with the inlet 1103 through a sixth pipeline 114, the second oxygen-side booster pump 113 is connected in series to the sixth pipe 114, the sixth pipe 114 is provided with a fourth valve 122, the fourth valve 122 is located on the outlet side of the second oxygen-side booster pump 113, the hydrogen-side separation inlet 1701 is communicated with the hydrogen-side outlet 1101 through the seventh pipe 13, the hydrogen-side gas-phase outlet 1702 is communicated with the eighth pipe 18, the eighth pipe 18 is provided with a fifth valve 19, the hydrogen-side liquid-phase outlet 1703 is communicated with the fifth pipe 111 through the ninth pipe 112, and the communication position is located downstream of the third valve 117.

The working process of the hydrogen production electrolyte circulation device provided by the first embodiment is as follows:

under the condition that the pressure of the hydrogen production system is 0.5-4.0MPa, electrolyte flows in from an electrolyte inlet 1103 of the electrolytic cell 11, the electrolyte respectively enters the anode chamber and the cathode chamber, after electrolytic reaction, the generated hydrogen and the electrolyte flow out from a hydrogen side outlet 1101 of the electrolytic cell 11, and the oxygen and the electrolyte obtained by the reaction flow out from an oxygen side outlet 1102 of the electrolytic cell 11; the gas-liquid mixture discharged from the hydrogen-side outlet 1101 enters the hydrogen-side gas-liquid separator 17, and separation of the electrolyte and a part of the hydrogen gas is achieved; the gas-liquid mixture discharged from the oxygen-side outlet 1102 enters the oxygen-side gas-liquid separator 14, and separation of the electrolyte and a part of the oxygen is achieved; the electrolyte separated by the oxygen-side gas-liquid separator 14 is discharged from an oxygen-side separation outlet 1403, is decompressed to 0-4.0MPa by a decompression valve 121, and then enters an oxygen-side flash evaporator 115, so that oxygen in the electrolyte is further separated, the oxygen flows out from an oxygen-side flash evaporation outlet 11502 and is merged with the discharged oxygen of the oxygen-side gas-liquid separator 14, the oxygen-side reduced pressure separation electrolyte flows into a first oxygen-side booster pump 116 from an oxygen-side flash evaporation liquid-phase outlet 11503 of the oxygen-side flash evaporation tank 115, the boosted oxygen-side reduced pressure separation electrolyte is merged with the hydrogen-side separation electrolyte discharged from a hydrogen-side gas-liquid separator 17 and then enters an oxygen-side cooling device 110, all cooled electrolytes are boosted to 0.5-4.0MPa by a second oxygen-side booster pump 113 and enter an electrolyte inlet 1103 of the electrolytic cell 11, and the whole system forms a circulation loop.

In the above circulation process, an oxygen side pressure reduction gas-liquid separation device is added at the oxygen side gas-liquid separation device 14, so that oxygen in the oxygen side separation electrolyte containing high oxygen content can be effectively removed, the oxygen content of the electrolyte circularly entering the electrolytic cell 11 is reduced, the hydrogen purity of the hydrogen side is improved, the operation convenience is brought to the subsequent purification process, and the energy consumption is reduced.

The hydrogen production electrolyte circulation device provided by the embodiment is suitable for the situation that the hydrogen purity is considered seriously under the condition that the oxygen purity is controllable.

Example two

As shown in fig. 2, the second embodiment provides a hydrogen production electrolyte circulation device including an oxygen-side electrolyte circulation device and a hydrogen-side electrolyte circulation device. Specifically, the above-mentioned circulation device for hydrogen production electrolyte comprises: a hydrogen-side gas-liquid separation device 27, an oxygen-side gas-liquid separation device 24, an oxygen-side depressurized gas-liquid separation device, a hydrogen-side depressurized gas-liquid separation device, an oxygen-side pressure boosting device, an oxygen-side transport device, a hydrogen-side pressure boosting device, a hydrogen-side transport device, an oxygen-side cooling device, a hydrogen-side cooling device, and a controller.

The oxygen-side pressure-reducing gas-liquid separation device and the hydrogen-side pressure-reducing gas-liquid separation device are the same pressure-reducing gas-liquid separation device, and specifically, the pressure-reducing gas-liquid separation device comprises a flash evaporator 213 and a pressure reducing valve 212 arranged in an inlet pipe of the flash evaporator 213. The hydrogen-side separated electrolyte discharged from the hydrogen-side gas-liquid separator 27 and the oxygen-side separated electrolyte discharged from the oxygen-side gas-liquid separator 24 are merged and then introduced into the flash evaporator 213 through the pressure reducing valve 212.

The oxygen side booster device, the oxygen side transport device, the hydrogen side booster device, and the hydrogen side transport device are the same device, and for the purpose of boosting, the oxygen side booster device, the oxygen side transport device, the hydrogen side booster device, and the hydrogen side transport device are the same booster pump 218. It will be appreciated that the booster pump 218 boosts and delivers both the hydrogen side reduced pressure separation electrolyte and the oxygen side reduced pressure separation electrolyte to the electrolytic cell 21.

The oxygen-side cooling device and the hydrogen-side cooling device are the same device, and specifically, the oxygen-side cooling device and the hydrogen-side cooling device are the same cooler 210, that is, the cooler 210 cools the hydrogen-side depressurized separation electrolyte and the oxygen-side depressurized separation electrolyte at the same time. The cooler 210 is upstream of the booster pump 218 and the cooler 210 is downstream of the flash evaporator 213.

The controller is configured to control the pressure reducing valve 212 to reduce the pressure of the oxygen-side separation electrolyte and the hydrogen-side separation electrolyte to within a first set pressure range, and the pressure increasing pump 218 to increase the pressure of the oxygen-side pressure reduction separation electrolyte and the hydrogen-side pressure reduction separation electrolyte to within a second set pressure range.

The first set pressure range is the first oxygen side set pressure range and the first hydrogen side set pressure range. It is understood that the first oxygen side set pressure range and the first hydrogen side set pressure range are the same pressure range. The second set pressure range is the second oxygen side set pressure range and also the second hydrogen side set pressure range. It is understood that the second oxygen side set pressure range and the second hydrogen side set pressure range are the same pressure range.

In the hydrogen production electrolyte circulation device provided in the second embodiment, the electrolytic cell 21 has the hydrogen-side outlet 2101, the oxygen-side outlet 2102, and the electrolyte inlet 2103, the oxygen-side gas-liquid separation device 24 has the oxygen-side separation inlet 2401, the oxygen-side gas-phase outlet 2402, and the oxygen-side liquid-phase outlet 2403, the hydrogen-side gas-liquid separation device 27 has the hydrogen-side separation inlet 2701, the hydrogen-side gas-phase outlet 2702, and the hydrogen-side liquid-phase outlet 2703, the flash evaporator 213 has the flash inlet 21301, the flash gas-phase outlet 21302, and the flash liquid-phase outlet 21303, and the cooler 210 has an inlet, an outlet, a cooling medium inlet, and a cooling medium outlet.

In order to realize the communication of the above components, the oxygen side separation inlet 2401 and the oxygen side outlet 2102 are communicated through a first pipeline 22, the oxygen side gas phase outlet 2402 is communicated with a second pipeline 25, the second pipeline 25 is provided with a first valve 26, the hydrogen side separation inlet 2701 is communicated with the hydrogen side outlet 2101 through a third pipeline 23, the hydrogen side gas phase outlet 2702 is communicated with a fourth pipeline 28, the fourth pipeline 28 is provided with a second valve 29, the hydrogen side liquid phase outlet 2703 and the oxygen side liquid phase outlet 2403 are both communicated with the flash evaporation inlet 21301 of the flash evaporator 213 through a fifth pipeline 211, the fifth pipeline 211 is an inlet pipe of the flash evaporator 213, a pressure reducing valve 212 is arranged on the fifth pipeline 211, and the fifth pipeline 211 is an inlet pipe of the flash evaporator 213; flash vapor phase outlet 21302 is in communication with sixth conduit 214, sixth conduit 214 is provided with third valve 215, sixth conduit 214 is in communication with second tube segment 25, flash liquid phase outlet 21303 is in communication with the inlet of cooler 210 via seventh conduit 216, the outlet of cooler 210 is in communication with electrolyte inlet 2103 via eighth conduit 217, booster pump 218 is connected in series to eighth conduit 217, and eighth conduit 217 is provided with fourth valve 219, which fourth valve 219 is located at the outlet side of booster pump 218.

The working process of the hydrogen production electrolyte circulation device provided by the second embodiment is as follows:

as shown in fig. 2, under the condition that the pressure of the hydrogen production system is 0.5-4.0MPa, the electrolyte flows in from an electrolyte inlet 2103 of the electrolytic cell 21, the electrolyte respectively enters the anode chamber and the cathode chamber, after the electrolytic reaction, the generated hydrogen and the electrolyte flow out from a hydrogen side outlet 2101 of the electrolytic cell 21, and the oxygen and the electrolyte obtained by the reaction flow out from an oxygen side outlet 2102 of the electrolytic cell 21; the gas-liquid mixture discharged from the hydrogen-side outlet 2101 is introduced into a hydrogen-side gas-liquid separation apparatus 27 to separate an electrolyte from a part of hydrogen gas; the gas-liquid mixture discharged from the oxygen-side outlet 2102 is introduced into the oxygen-side gas-liquid separation apparatus 24 to separate the electrolyte from a part of the oxygen; hydrogen flows out from the hydrogen side gas phase outlet 2702, oxygen flows out from the oxygen side gas phase outlet 2402, and the hydrogen and the oxygen can enter the next purification process; the oxygen side separated electrolyte flowing out from the oxygen side liquid phase outlet 2403 and the hydrogen side separated electrolyte flowing out from the hydrogen side liquid phase outlet 2703 are converged, decompressed to 0-4.0MPa by the decompression valve 212, enters the flash tank from the flash inlet 21301 of the flash tank 213 for flash evaporation, and flows out from the flash vapor phase outlet 21302 of the flash tank 213 for vapor phase, and then is converged with the oxygen discharged from the oxygen side gas-liquid separation device 24; the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte enter the cooler 210 from the flash liquid phase outlet 21303, are cooled by the cooler 210, are increased in pressure by the booster pump 218 to the pressure of 0.5-4.0MPa of the hydrogen production system, and enter the electrolytic cell 21.

In the second embodiment, the hydrogen production electrolyte circulation device adopts the same flash evaporator 213 and the same pressure reducing valve 212 to perform pressure reduction gas-liquid separation on the oxygen side separation electrolyte and the hydrogen side separation electrolyte, so that the number of devices is reduced, the structure is simplified, and the cost is reduced.

The hydrogen production electrolyte circulation device provided by the second embodiment reduces the gas content of the electrolyte and improves the hydrogen purity; on the other hand, higher system pressure is maintained, and the operation energy consumption of the whole device is reduced; in addition, the reduction of the efficiency of the cooler 210 caused by the generation of bubbles in the cooler 210 due to the gas evolution of the electrolyte in the cooler 210 is avoided, and the energy consumption of the operation is further reduced.

Example three:

as shown in fig. 3, the hydrogen production electrolyte circulation device provided in the third embodiment includes an oxygen-side electrolyte circulation device and a hydrogen-side electrolyte circulation device. Specifically, the above-mentioned circulation device for hydrogen production electrolyte comprises: a hydrogen-side gas-liquid separation device 37, an oxygen-side gas-liquid separation device 34, an oxygen-side depressurized gas-liquid separation device, a hydrogen-side depressurized gas-liquid separation device, an oxygen-side pressure boosting device, an oxygen-side transport device, a hydrogen-side pressure boosting device, a hydrogen-side transport device, an oxygen-side cooling device, a hydrogen-side cooling device, and a controller.

The oxygen side pressure reduction gas-liquid separation device comprises an oxygen side flash evaporator 313 and an oxygen side pressure reducing valve 315 arranged in an inlet pipe of the oxygen side flash evaporator 313, and the hydrogen side pressure reduction gas-liquid separation device comprises a hydrogen side flash evaporator 316 and a hydrogen side pressure reducing valve 318 arranged in an inlet pipe of the hydrogen side flash evaporator 316.

The oxygen side pressure increasing device, the oxygen side transport device, the hydrogen side pressure increasing device, and the hydrogen side transport device are the same device, and for the convenience of pressure increase, the oxygen side pressure increasing device, the oxygen side transport device, the hydrogen side pressure increasing device, and the hydrogen side transport device are the same pressure increasing pump 319. It will be appreciated that the booster pump 319 boosts and delivers both the hydrogen side reduced pressure separation electrolyte and the oxygen side reduced pressure separation electrolyte to the electrolytic cell 31.

The oxygen-side cooling device and the hydrogen-side cooling device are the same device, and specifically, the oxygen-side cooling device and the hydrogen-side cooling device are the same cooler 310, that is, the cooler 310 cools the hydrogen-side depressurized separation electrolyte and the oxygen-side depressurized separation electrolyte at the same time. The cooler 310 is upstream of the booster pump 319, the cooler 310 is downstream of the oxygen-side flash vessel 313, and the cooler 310 is also downstream of the hydrogen-side flash vessel 316.

The controller is configured to control the oxygen-side pressure reducing valve 315 to reduce the pressure of the oxygen-side separated electrolyte to within a first oxygen-side set pressure range, the hydrogen-side pressure reducing valve 318 to reduce the pressure of the hydrogen-side separated electrolyte to within a first hydrogen-side set pressure range, and the booster pump 319 to increase the pressure of the oxygen-side reduced separated electrolyte and the pressure of the hydrogen-side reduced separated electrolyte to within a second set pressure range.

The second set pressure range is the second set pressure range in the second embodiment.

In the circulation device for producing hydrogen electrolyte provided in the third embodiment, the electrolytic cell 31 has a hydrogen-side outlet 3101, an oxygen-side outlet 3102 and an electrolyte inlet 3103, the oxygen-side gas-liquid separation device 34 has an oxygen-side separation inlet 3401, an oxygen-side gas-phase outlet 3402 and an oxygen-side liquid-phase outlet 3403, the hydrogen-side gas-liquid separation device 37 has a hydrogen-side separation inlet 3701, a hydrogen-side gas-phase outlet 3702 and a hydrogen-side liquid-phase outlet 3703, the oxygen-side flash evaporator 313 has an oxygen-side flash evaporation inlet 31301, an oxygen-side flash vapor outlet 31302 and an oxygen-side flash liquid-phase outlet 31303, the hydrogen-side flash evaporator 316 has a hydrogen-side flash evaporation inlet 31601, a hydrogen-side flash evaporation gas-phase outlet 31602 and a hydrogen-side flash evaporation liquid-phase outlet 31603, and the cooler 210 has an inlet, an outlet, a cooling medium inlet and a cooling medium outlet.

In order to communicate the respective components, the oxygen-side separation inlet 3401 and the oxygen-side outlet 3102 communicate with each other through a first pipe 32, the oxygen-side gas phase outlet 3402 communicates with a second pipe 35, and the second pipe 35 is provided with a first valve 36; the hydrogen-side separation inlet 3701 communicates with the hydrogen-side outlet 3101 through the third pipe 33, the hydrogen-side gas phase outlet 3702 communicates with the fourth pipe 38, and the fourth pipe 38 is provided with the second valve 39; the oxygen side liquid phase outlet 3403 is communicated with the oxygen side flash inlet 31301 of the oxygen side flash evaporator 313 through a fifth pipeline 314, at this time, the fifth pipeline 314 is an inlet pipe of the oxygen side flash evaporator 313, and the oxygen side pressure reducing valve 315 is arranged on the fifth pipeline 314; the hydrogen-side liquid phase outlet 3703 is communicated with a hydrogen-side flash evaporation inlet 31601 of the hydrogen-side flash evaporator 316 through a sixth pipeline 317, at this time, the sixth pipeline 317 is an inlet pipe of the hydrogen-side flash evaporator 316, and the hydrogen-side pressure reducing valve 318 is arranged on the sixth pipeline 317; the oxygen side flash liquid phase outlet 31303 and the hydrogen side flash liquid phase outlet 31603 are both communicated with the inlet of the cooler 310 through a seventh conduit 311, the oxygen side flash vapor phase outlet 31302 and the hydrogen side flash vapor phase outlet 31602 are both communicated with the second conduit 35 through an eighth conduit 321, the eighth conduit 321 is provided with a third valve 322 and a fourth valve 323, the third valve 322 is located at the outlet of the oxygen side flash evaporator 313, and the fourth valve 323 is located at the outlet of the hydrogen side flash evaporator 316; the outlet of the cooler 310 communicates with an electrolyte inlet 3103 of the electrolytic cell 31 through a ninth conduit 312, the booster pump 319 is provided in the ninth conduit 312, and the ninth conduit 312 is provided with a fifth valve 320.

The working process of the hydrogen production electrolyte circulation device provided by the third embodiment is as follows:

as shown in fig. 3, under the condition that the pressure of the hydrogen production system is 0.5-4.0MPa, the electrolyte flows in from the electrolyte inlet 3103 of the electrolytic cell 31, the electrolyte respectively enters the anode chamber and the cathode chamber, after the electrolytic reaction, the generated hydrogen and the electrolyte flow out from the hydrogen side outlet 3101 of the electrolytic cell 31, and the oxygen and the electrolyte obtained by the reaction flow out from the oxygen side outlet 3102 of the electrolytic cell 31; the gas-liquid mixture flowing out of the oxygen side outlet 3102 enters an oxygen side gas-liquid separation device 34, and the oxygen side separated electrolyte separated by the oxygen side gas-liquid separation device 34 is decompressed to 0-4.0MPa by an oxygen side pressure reducing valve 315 and then enters an oxygen side flash evaporator 313; the gas-liquid mixture flowing out of the hydrogen-side outlet 3101 enters the hydrogen-side gas-liquid separation device 37, and the hydrogen-side separated electrolyte separated by the hydrogen-side gas-liquid separation device 37 is decompressed to 0-4.0MPa by the hydrogen-side pressure reducing valve 318 and then enters the hydrogen-side flash evaporator 316; the oxygen separated by the oxygen-side gas-liquid separation device 34 and the hydrogen separated by the hydrogen-side gas-liquid separation device 37 can both enter the next purification process; the oxygen discharged from the oxygen side flash evaporator 313 and the hydrogen discharged from the hydrogen side flash evaporator 316 are merged and then merged with the oxygen discharged from the oxygen side gas-liquid separation device 34, and the oxygen side reduced-pressure separated electrolyte discharged from the oxygen side flash evaporator 313 and the hydrogen side reduced-pressure separated electrolyte discharged from the hydrogen side flash evaporator 316 are merged and then enter the cooler 310, are cooled by the cooler 310, and then enter the electrolytic cell 31 after being boosted in pressure by the booster pump 319.

Example four

As shown in fig. 4, the hydrogen production electrolyte circulation device according to the fourth embodiment includes an oxygen-side electrolyte circulation device and a hydrogen-side electrolyte circulation device. Specifically, the above-mentioned circulation device for hydrogen production electrolyte comprises: a hydrogen-side gas-liquid separation device 47, an oxygen-side gas-liquid separation device 44, an oxygen-side depressurized gas-liquid separation device, a hydrogen-side depressurized gas-liquid separation device, an oxygen-side pressure boosting device, an oxygen-side transport device, a hydrogen-side pressure boosting device, a hydrogen-side transport device, an oxygen-side cooling device, a hydrogen-side cooling device, and a controller.

The oxygen side pressure reduction gas-liquid separation device and the hydrogen side pressure reduction gas-liquid separation device are the same pressure reduction gas-liquid separation device, and the two pressure reduction gas-liquid separation devices are respectively a first pressure reduction gas-liquid separation device and a second pressure reduction gas-liquid separation device. Specifically, the first pressure-reducing gas-liquid separation device comprises a first flash evaporator 413 and a first pressure-reducing valve 412 arranged in an inlet pipe of the first flash evaporator 413, and the second pressure-reducing gas-liquid separation device comprises a second flash evaporator 416 and a second pressure-reducing valve 415 arranged in an inlet pipe of the second flash evaporator 416; both the oxygen-side liquid phase outlet 4403 of the oxygen-side gas-liquid separation device 44 and the hydrogen-side liquid phase outlet 4703 of the hydrogen-side gas-liquid separation device 47 are communicated with the first flash inlet 41301 of the first flash evaporator 413, and the first flash liquid phase outlet 41303 of the first flash evaporator 413 is communicated with the second flash inlet 41601 of the second flash evaporator 416.

The oxygen side pressure increasing device, the oxygen side transport device, the hydrogen side pressure increasing device, and the hydrogen side transport device are the same device, and for the convenience of pressure increase, the oxygen side pressure increasing device, the oxygen side transport device, the hydrogen side pressure increasing device, and the hydrogen side transport device are the same pressure increasing pump 419. It will be appreciated that the booster pump 419 boosts and delivers both the hydrogen side reduced pressure separation electrolyte and the oxygen side reduced pressure separation electrolyte to the electrolytic cell 41.

The oxygen-side cooling device and the hydrogen-side cooling device are the same device, and specifically, the oxygen-side cooling device and the hydrogen-side cooling device are the same cooler 410, that is, the cooler 410 cools the hydrogen-side depressurized separation electrolyte and the oxygen-side depressurized separation electrolyte at the same time. The cooler 410 is upstream of the booster pump 419 and the cooler 410 is downstream of the second flash evaporator 416.

The controller is configured to control the first pressure reducing valve 412 to reduce the pressure of the oxygen-side separation electrolyte and the hydrogen-side separation electrolyte to within a third set pressure range, the second pressure reducing valve 415 to reduce the pressure of the oxygen-side separation electrolyte and the hydrogen-side separation electrolyte to within a fourth set pressure range, and the pressure increasing pump 419 to increase the pressure of the oxygen-side pressure reduction separation electrolyte and the hydrogen-side pressure reduction separation electrolyte to within a second set pressure range.

The set of the third set pressure range and the fourth set pressure range is the first set pressure range in the second embodiment, and the second set pressure range is the second set pressure range in the second embodiment.

In the hydrogen-producing electrolyte circulation apparatus provided in the fourth embodiment, the electrolytic cell 41 has a hydrogen-side outlet 4101, an oxygen-side outlet 4102 and an electrolyte inlet 4103, the oxygen-side gas-liquid separating device 44 has an oxygen-side separating inlet 4401, an oxygen-side gas-phase outlet 4402 and an oxygen-side liquid-phase outlet 4403, the hydrogen-side gas-liquid separating device 47 has a hydrogen-side separating inlet 4701, a hydrogen-side gas-phase outlet 4702 and a hydrogen-side liquid-phase outlet 4703, the first flash evaporator 413 has a first flash evaporation inlet 41301, a first flash vapor outlet 41302 and a first flash vapor outlet 41303, the second flash evaporator 416 has a second flash evaporation inlet 41601, a second flash evaporation gas outlet 41602 and a second flash evaporation liquid-phase outlet 41603, and the cooler 410 has an inlet, an outlet, a cooling medium inlet and a cooling medium outlet.

In order to realize the communication of the above components, the oxygen side separation inlet 4401 and the oxygen side outlet 4102 are communicated through a first pipeline 42, the oxygen side gas phase outlet 4402 is communicated with a second pipeline 45, the second pipeline 45 is provided with a first valve 46, the hydrogen side separation inlet 4701 is communicated with the hydrogen side outlet 4101 through a third pipeline 43, the hydrogen side gas phase outlet 4702 is communicated with a fourth pipeline 48, the fourth pipeline 48 is provided with a second valve 49, the hydrogen side liquid phase outlet 4703 and the oxygen side liquid phase outlet 4403 are both communicated with the first flash inlet 41301 through a fifth pipeline 411, in this case, the fifth pipeline 411 is the inlet pipe of the first flash device 413, the first pressure reducing valve 412 is arranged on the fifth pipeline 411, in this case, the fifth pipeline 411 is the inlet pipe of the first flash device 413; the first flash vapor phase outlet 41302 is communicated with a sixth pipeline 421, the sixth pipeline 421 is provided with a third valve 422, the third valve 422 is close to the first flash vapor phase outlet 41302, the sixth pipeline 421 is communicated with the second pipeline 45, the first flash vapor phase outlet 41303 is communicated with the second flash vapor inlet 41601 through a seventh pipeline 414, at this time, the seventh pipeline 414 is an inlet pipe of the second flash evaporator 416, the seventh pipeline 414 is provided with a second pressure reducing valve 415, the second flash vapor phase outlet 41602 is communicated with the sixth pipeline 421, the sixth pipeline 421 is provided with a fourth valve 423, and the fourth valve 423 is close to the second flash vapor phase outlet 41602; the second flash liquid phase outlet 41603 is communicated with the inlet of the cooler 410 through an eighth pipe 417, the outlet of the cooler 410 is communicated with the electrolyte inlet 4103 through a ninth pipe 418, the booster pump 419 is provided in the ninth pipe 418, the ninth pipe 418 is provided with a fifth valve 420, and the fifth valve 420 is located at the outlet side of the booster pump 419.

The working process of the hydrogen production electrolyte circulation device provided by the fourth embodiment is as follows:

as shown in fig. 4, under the condition that the pressure of the hydrogen production system is 0.5-4.0MPa, the electrolyte flows in from the electrolyte inlet 4103 of the electrolytic cell 41, the electrolyte respectively enters the anode chamber and the cathode chamber, after the electrolytic reaction, the generated hydrogen and the electrolyte flow out from the hydrogen side outlet 4101 of the electrolytic cell 41, and the oxygen and the electrolyte obtained by the reaction flow out from the oxygen side outlet 4102 of the electrolytic cell 41; the gas-liquid mixture discharged from the hydrogen-side outlet 4101 enters the hydrogen-side gas-liquid separator 47 to separate the electrolyte and a part of the hydrogen gas; the gas-liquid mixture discharged from the oxygen-side outlet 4102 is introduced into the oxygen-side gas-liquid separation device 44 to separate the electrolyte and a part of the oxygen gas; hydrogen flows out from a hydrogen side gas phase outlet 4702, oxygen flows out from an oxygen side gas phase outlet 4402, and the hydrogen and the oxygen can enter the next purification process; the oxygen side separated electrolyte flowing out of the oxygen side liquid phase outlet 4403 and the hydrogen side separated electrolyte flowing out of the hydrogen side liquid phase outlet 4703 are merged, decompressed to 0-4.0MPa by a first decompression valve 412, and then enter a first flash tank 413 from a first flash inlet 41301 for flash evaporation, and a gas phase flows out of a first flash vapor phase outlet 41302 and then is merged with oxygen discharged by an oxygen side gas-liquid separation device 44; the oxygen side pressure reduction separation electrolyte and the hydrogen side pressure reduction separation electrolyte flow out from a first flash liquid phase outlet 41303, are reduced in pressure to 0-4.0MPa through a second pressure reducing valve 415, then enter a second flash inlet 41601 to carry out second flash evaporation, a gas phase flows out from a second flash gas phase outlet 41602, then gas flowing out from a first flash gas phase outlet 41302 is converged, and then is converged with oxygen discharged from the oxygen side gas-liquid separation device 44; the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte flow out from the second flash liquid phase outlet 41603, then enter the cooler 410, are boosted to the pressure of 0.5-4.0MPa of the hydrogen production system through the booster pump 419, and then enter the electrolytic tank 41.

The hydrogen production electrolyte circulation device provided by the fourth embodiment realizes twice depressurization gas-liquid separation, and further improves the hydrogen purity.

Based on the hydrogen production electrolyte circulation device provided by the embodiment, the embodiment of the invention also provides a hydrogen production system, which comprises the electrolyte circulation device, wherein the electrolyte circulation device is the hydrogen production electrolyte circulation device provided by the embodiment.

Since the hydrogen production electrolyte circulation device provided by the above embodiment has the above technical effects, and the hydrogen production system provided by the above embodiment includes the above hydrogen production electrolyte circulation device, the hydrogen production system provided by the above embodiment also has corresponding technical effects, and details are not described herein.

It should be noted that the electrolyte mentioned herein may be alkaline solution or pure water, and is selected according to actual needs, which is not limited in this embodiment.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of recycling a hydrogen producing electrolyte, comprising:

an oxygen-side electrolyte circulation method and/or a hydrogen-side electrolyte circulation method;

2. The recycling method according to claim 1,

the oxygen side electrolyte circulation method further includes the steps of: cooling the oxygen side reduced pressure separation electrolyte before or after the step of boosting the oxygen side reduced pressure separation electrolyte;

3. The recycling method according to claim 1,

carrying out depressurization gas-liquid separation on the oxygen side separation electrolyte and the hydrogen side separation electrolyte by adopting the same depressurization gas-liquid separation device;

4. The recycling method according to claim 1,

the same booster pump is adopted to boost the oxygen side reduced pressure separation electrolyte and the hydrogen side reduced pressure separation electrolyte;

5. The recycling method according to claim 1,

in the oxygen side electrolyte circulation method, the pressure of the oxygen side separation electrolyte is reduced to 0-4.0MPa, and the pressure of the oxygen side reduction separation electrolyte is increased to 0.5-4.0 MPa; in the hydrogen side electrolyte circulation method, the pressure of the hydrogen side separation electrolyte is reduced to 0-4.0MPa, and the pressure of the hydrogen side reduced pressure separation electrolyte is increased to 0.5-4.0 MPa.

6. A method for producing hydrogen, comprising the recycling method according to any one of claims 1 to 5.

7. A circulation device for hydrogen production electrolyte, comprising:

an oxygen-side electrolyte circulation device and/or a hydrogen-side electrolyte circulation device;

8. The recycling apparatus according to claim 7,

the oxygen-side electrolyte circulation device further includes: an oxygen side cooling device for cooling the oxygen side reduced pressure separation electrolyte; wherein the oxygen-side cooling device is located upstream or downstream of the oxygen-side pressure-increasing device;

9. The circulation device according to claim 8, wherein the oxygen-side cooling device and the hydrogen-side cooling device are the same device.

10. The recycling apparatus according to claim 11,

the oxygen side booster device and the oxygen side delivery device are the same booster pump;

11. The recycling apparatus according to claim 7, wherein the hydrogen-side pressure-reducing gas-liquid separation apparatus and the oxygen-side pressure-reducing gas-liquid separation apparatus are the same apparatus, or the hydrogen-side pressure-reducing gas-liquid separation apparatus and the oxygen-side pressure-reducing gas-liquid separation apparatus are not the same apparatus.

12. The circulation device according to claim 7, wherein the hydrogen-side pressure boosting device and the oxygen-side pressure boosting device are the same device, or the hydrogen-side pressure boosting device and the oxygen-side pressure boosting device are not the same device.

13. The recycling apparatus according to claim 7,

the oxygen-side electrolyte circulation device further includes: an oxygen side controller for controlling the oxygen side pressure-reducing gas-liquid separation device to reduce the pressure of the oxygen side separated electrolyte to within a first oxygen side set pressure range and for controlling the oxygen side pressure-increasing device to increase the pressure of the oxygen side pressure-reducing separated electrolyte to within a second oxygen side set pressure range;

14. The recycling apparatus according to claim 13, wherein the oxygen-side controller and the hydrogen-side controller are integrated.

15. A hydrogen production system comprising an electrolyte circulation device, wherein the electrolyte circulation device is a circulation device according to any one of claims 7 to 14.