Iron suspended matter settling device, water electrolysis hydrogen production device system and application of water electrolysis hydrogen production device system

Abstract

The invention relates to an iron suspended matter settling device, a water electrolysis hydrogen production device system and application of the water electrolysis hydrogen production device system, the iron suspended matter settling device is simple in structure, can avoid the adverse effect of dissolved iron suspended matter on the stability of the water electrolysis hydrogen production device system, and can also remove iron generated by a pipeline of the water electrolysis hydrogen production system. By using the suspended iron settling device, the problem that the resistance of the diaphragm is increased due to the fact that part of micropores of the diaphragm are blocked by suspended iron can be solved, the problems that the electrolysis energy consumption is increased and the cathode hydrogen evolution performance is reduced are solved, the performance of a water electrolysis hydrogen production device system is improved, and the service life of the water electrolysis hydrogen production device system is prolonged.

Description

Technical Field

[0001] The present invention belongs to the technical field of water electrolysis hydrogen production, and relates to an alkaline water electrolysis hydrogen production system and applications thereof, and in particular to an iron suspension sedimentation device, a water electrolysis hydrogen production device system and applications thereof. Background Art

[0002] Alkaline water electrolysis is the current mainstream method for producing hydrogen by water electrolysis. The electrolysis process includes the anodic oxygen evolution reaction and the cathode hydrogen evolution reaction in the alkaline electrolyte. The overpotential and current density of these two electrochemical reactions have a crucial influence on the energy consumption and hydrogen production rate of water electrolysis.

[0003] Precious metals Ru or Ir have good oxygen evolution performance in the oxygen evolution reaction (OER), but they are expensive and not suitable for large-scale use. Nickel mesh, nickel foam or Raney nickel are often used as oxygen evolution electrode materials in industry, but due to the limited OER activity of nickel itself, these electrodes cannot meet the needs of high current density water electrolysis for hydrogen production.

[0004] The nickel-iron electrode obtained by adding a small amount of iron to nickel can greatly improve the oxygen evolution current density. The nickel-iron electrode shows excellent oxygen evolution activity and stability in low-concentration alkaline solution, but there is a defect that the iron element dissolves slowly under high temperature and strong alkaline conditions. The solubility of iron in alkaline electrolyte is not high, and solid suspended matter or precipitation such as iron hydroxide or oxide will gradually form. On the one hand, the suspended matter or precipitation will block some of the micropores of the diaphragm, resulting in an increase in the resistance of the diaphragm, further leading to an increase in the energy consumption of electrolysis; on the other hand, the suspended matter or precipitation is deposited on the cathode, resulting in a decrease in the hydrogen evolution performance of the cathode.

[0005] CN114717608A discloses a long-life alkaline water electrolysis system and control method, the system includes a hydrogen separator, an oxygen separator and an electrolyzer, the liquid outlets of the hydrogen separator and the oxygen separator are connected to an alkaline solution circulation pump, the alkaline solution circulation pump is connected to an adsorption unit, an alkaline solution cooler and an electrolyzer liquid inlet in sequence through a pipeline, and the two gas outlets of the electrolyzer are connected to the gas inlets of the hydrogen separator and the oxygen separator respectively through pipelines; the gas outlet is connected to a dealkalization unit in sequence through a pipeline. It removes impurities in the alkaline electrolyte through the adsorption unit, but the adsorption unit is a filtering device in conventional technology and is only suitable for solid particles with larger particle sizes.

[0006] CN103463872A discloses a single-layer dust reduction chamber, which includes a dust reduction box, a gas inlet pipe and a gas outlet pipe are respectively arranged on the front and rear sides of the dust reduction box, a plurality of dust particle hoppers are arranged on the bottom surface of the dust reduction chamber, and cross-direction change plates are evenly arranged in the dust reduction box. The single-layer dust reduction chamber can settle large solid particles, but cannot be used for the separation of iron oxides or hydroxides with smaller particle sizes.

[0007] Since the particle size of solid suspended matter or precipitate such as iron hydroxide or oxide is small (particle size ≤ 30 μm), it is difficult to remove it through conventional filtering devices; the use of mesh filtering devices with too fine pores will increase the flow resistance of alkaline electrolyte, thereby causing the flow rate of electrolyte to decrease. Therefore, it is necessary to provide a low-impedance iron suspended matter sedimentation device, a water electrolysis hydrogen production device system and its application. Summary of the invention

[0008] The object of the present invention is to provide an iron suspension sedimentation device, a water electrolysis hydrogen production device system and applications thereof. The use of the iron suspension sedimentation device in the water electrolysis hydrogen production device system can effectively sediment the iron suspension in the electrolyte, solve the problem of iron suspension blocking the micropores of the diaphragm part, and avoid the increase of diaphragm resistance, the increase of energy consumption and the decrease of cathode hydrogen evolution performance.

[0009] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides an iron suspension sedimentation device, the iron suspension sedimentation device comprising a sedimentation chamber;

[0011] The sedimentation chamber is divided into a liquid inlet sedimentation chamber and a liquid outlet sedimentation chamber by a baffle plate; the top of the liquid inlet sedimentation chamber is connected to the top of the liquid outlet sedimentation chamber;

[0012] The side wall of the liquid inlet sedimentation chamber is provided with a liquid inlet, and the side wall of the liquid outlet sedimentation chamber is provided with a liquid outlet; the heights of the liquid inlet and the liquid outlet are both lower than the height of the baffle, and the height of the liquid outlet is higher than the height of the liquid inlet;

[0013] A liquid outlet baffle is obliquely arranged in the liquid outlet sedimentation chamber; one end of the liquid outlet baffle is connected to the side wall above the liquid outlet, and the other end extends to the bottom of the liquid outlet.

[0014] The iron suspension sedimentation device provided by the present invention changes the flow direction of the electrolyte in the iron suspension sedimentation device through the arrangement of the baffle baffle and the outlet baffle, thereby reducing the electrolyte flow rate. When the electrolyte in the inlet sedimentation chamber flows upward, the iron suspension in the electrolyte gradually settles due to the gravity and the slowing down of the flow rate; the iron suspension that has not settled in the inlet sedimentation chamber passes over the baffle baffle with the electrolyte and changes the flow direction, and further settles the iron suspension in combination with the gravity; the supernatant in the outlet sedimentation chamber is decelerated by the outlet baffle, settles again, and finally flows out at the outlet.

[0015] Necessary valves are also provided at the liquid inlet and liquid outlet of the iron suspension sedimentation device of the present invention, and the present invention does not make any specific limitation here.

[0016] The use of the iron suspension sedimentation device of the present invention can solve the problem of iron suspension blocking some micropores of the diaphragm and causing increased diaphragm resistance, solve the problem of increased electrolysis energy consumption and decreased cathode hydrogen evolution performance, and improve the performance and service life of the water electrolysis hydrogen production device system.

[0017] Preferably, the top of the settling chamber is provided with an exhaust port;

[0018] The exhaust port is provided with an exhaust valve.

[0019] The present invention provides an exhaust port at the top of the settling chamber and an exhaust valve at the exhaust port, so that when the pressure in the settling chamber exceeds a specified value, the exhaust valve is opened to release the pressure, thereby ensuring the safe operation of the iron suspension settling device.

[0020] Preferably, a pressure sensor is provided in the settling chamber, and the pressure sensor is electrically connected to an external control device, and the pressure sensor transmits the collected pressure signal to the control device, and the control device controls the opening and closing of the exhaust valve by comparing the set pressure with the collected pressure.

[0021] Exemplarily, the control device includes but is not limited to an industrial computer.

[0022] Exemplarily, the settling chamber of the present invention comprises a shell and a top cover; the top cover is flange-connected to the shell; the exhaust port is arranged on the top cover. The present invention can ensure the airtightness of the settling chamber and facilitate the maintenance of the settling chamber by operators by flange-connecting the top cover to the shell.

[0023] Preferably, the iron suspension sedimentation device is further provided with an external magnetic attraction device;

[0024] The external magnetic attraction device is arranged outside the sedimentation chamber and below the liquid inlet.

[0025] The external magnetic device described in the present invention includes but is not limited to a magnet; the present invention can accelerate the sedimentation of suspended iron by setting the external magnetic device; and the external magnetic device is set below the liquid inlet, ensuring that the suspended iron can be attracted by the external force of the magnet from the liquid inlet, thereby increasing the sedimentation efficiency; in addition, the liquid outlet of the iron suspension sedimentation device is higher than the liquid inlet, ensuring that the supernatant is not affected by the suspended iron attracted by the magnet, and the suspended iron in the supernatant can be effectively removed.

[0026] Preferably, the volume of the liquid inlet sedimentation chamber is greater than the volume of the liquid outlet sedimentation chamber.

[0027] The present invention increases the flow rate in the liquid outlet sedimentation chamber by making the volume of the liquid inlet sedimentation chamber larger than the volume of the liquid outlet sedimentation chamber. Combined with the effect of gravity, it is beneficial for the suspended matter that has not settled in the liquid inlet sedimentation chamber to settle in the liquid outlet sedimentation chamber.

[0028] Preferably, a sewage outlet is provided at the bottom of the liquid inlet sedimentation chamber and / or the liquid outlet sedimentation chamber.

[0029] The sewage outlet at the bottom of the liquid inlet sedimentation chamber and / or the liquid outlet sedimentation chamber is conducive to discharging the dirt in the sedimentation chamber; as a further preferred technical solution, the sewage outlet cooperates with the external magnetic suction device. When the sewage outlet is opened for sewage discharge operation, the external magnetic suction device can be moved to loosen the sediment, which is conducive to the discharge of the sediment and avoids the blockage of the sewage outlet by the sediment.

[0030] Preferably, the outer wall of the sedimentation chamber is provided with a heat-insulating material.

[0031] The thermal insulation material is a conventional thermal insulation material, and the present invention does not make any specific limitation here, as long as it can achieve the thermal insulation effect.

[0032] Further preferably, a temperature sensor is provided in the settling chamber for measuring the temperature of the electrolyte in the settling chamber.

[0033] Preferably, the material of the sedimentation chamber includes corrosion-resistant material.

[0034] The corrosion-resistant material of the present invention is a material resistant to corrosion by chloride ions and trivalent iron ions.

[0035] Preferably, the sedimentation chamber is made of stainless steel or carbon steel with nickel-plated inner wall.

[0036] Exemplarily, the stainless steel includes but is not limited to 316L stainless steel.

[0037] Preferably, the suspended iron sedimentation device further comprises a liquid level measuring device; the liquid level measuring device is used to detect the liquid level height in the sedimentation chamber.

[0038] In a second aspect, the present invention provides a water electrolysis hydrogen production device system, wherein the water electrolysis hydrogen production device system comprises the iron suspension sedimentation device described in the first aspect.

[0039] The use of the iron suspension sedimentation device in the water electrolysis hydrogen production device system of the present invention can solve the problem of iron suspension blocking part of the micropores of the diaphragm and causing the diaphragm resistance to increase, solve the problem of increased electrolysis energy consumption and decreased cathode hydrogen evolution performance, and improve the performance and service life of the water electrolysis hydrogen production device system.

[0040] Preferably, the water electrolysis hydrogen production device system comprises an electrolyzer, a hydrogen separator, an oxygen separator and a post-processing unit;

[0041] The post-processing unit comprises a cooling device, a filtering device and the iron suspension sedimentation device described in the first aspect;

[0042] The two outlets of the electrolyzer are connected to the feed ports of the hydrogen separator and the oxygen separator through pipelines respectively; the liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the post-processing unit; and the liquid outlet of the post-processing unit is connected to the liquid inlet of the electrolyzer.

[0043] The water electrolysis hydrogen production device system of the present invention also includes a circulation device for driving the flow of electrolyte, including but not limited to a circulation pump.

[0044] The filtering device in the post-processing unit described in the present invention is a conventional filtering device in the art. The conventional filtering device in the art can only filter solid impurities and cannot effectively filter magnetic iron suspensions. The present invention does not impose too many limitations on its structure.

[0045] Preferably, a sampling port is provided at the liquid inlet or outlet of the circulation pump to facilitate sampling, analysis and detection.

[0046] The water electrolysis hydrogen production device of the present invention also includes an alkali tank for preparing and storing electrolyte, and a water tank for storing water that needs to be replenished.

[0047] The present invention does not limit the specific positions of the alkali tank and the water tank, as long as electrolysis of water and water replenishment can be achieved.

[0048] Exemplarily, when the water electrolysis hydrogen production device system is used, a DC power supply is used to power the electrolyzer, and the electrolyte in the electrolyzer is electrolyzed to form hydrogen and oxygen; hydrogen enters the hydrogen separator with the electrolyte, and oxygen enters the oxygen separator with the electrolyte. Hydrogen is discharged through the upper end of the hydrogen separator for subsequent treatment; oxygen is discharged through the upper end of the oxygen separator for subsequent treatment. The lower ends of the hydrogen separator and the oxygen separator are electrolyte outlets, which enter the post-processing unit for cooling, filtering and sedimentation treatment, and flow into the electrolyzer for circulation.

[0049] As a further preferred technical solution, the water electrolysis hydrogen production device system also includes a control device; illustratively, the control device includes but is not limited to an industrial computer; the control device controls the opening and closing of the required valves according to the measured values ​​of the liquid level measuring device, the temperature sensor or the pressure sensor. The present invention is not further limited here, and those skilled in the art can make reasonable settings according to needs.

[0050] Preferably, the post-processing unit comprises a cooling device, a filtering device and an iron suspension sedimentation device connected in sequence;

[0051] The liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the cooling device;

[0052] The liquid outlet of the iron suspension sedimentation device is connected to the liquid inlet of the electrolytic cell;

[0053] or,

[0054] The post-processing unit comprises a cooling device, an iron suspension sedimentation device and a filtering device connected in sequence;

[0055] The liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the cooling device;

[0056] The liquid outlet of the cooling device is connected to the liquid inlet of the electrolytic cell;

[0057] or,

[0058] The post-processing unit includes an iron suspension sedimentation device, a cooling device and a filtering device connected in sequence;

[0059] The liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the iron suspension sedimentation device;

[0060] The liquid outlet of the filtering device is connected to the liquid inlet of the electrolytic cell.

[0061] Preferably, the iron suspension sedimentation device is located below the bottom of the oxygen separator and the hydrogen separator.

[0062] The present invention enables the position of the iron suspension sedimentation device to be lower than the bottom of the oxygen separator and the hydrogen separator, which is beneficial to the circulation of electrolyzed water.

[0063] In a third aspect, the present invention provides an application of the water electrolysis hydrogen production device system described in the second aspect, wherein the water electrolysis hydrogen production device system uses an iron suspension sedimentation device to remove iron suspension in the electrolyzed water during the water electrolysis hydrogen production process.

[0064] Exemplarily, the application includes the following steps:

[0065] (1) a KOH electrolyte with a concentration of 30 wt% is prepared in an alkali tank, and the electrolyte is pumped into an iron suspension sedimentation device through a circulation pump to ensure that the inlet flow rate of the iron suspension sedimentation device is consistent with the outlet flow rate, and then the inlet and outlet of the iron suspension sedimentation device are closed;

[0066] (2) pumping the electrolyte into the water electrolysis hydrogen production device system through a circulation pump, so that the liquid levels of the hydrogen separator and the oxygen separator reach the process height, and then opening the liquid inlet and liquid outlet of the iron suspension sedimentation device to allow the iron suspension sedimentation device to participate in the alkali solution circulation;

[0067] (3) Turn on the water electrolysis system to start electrolysis. The electrolyte in the electrolytic cell is electrolyzed to form hydrogen and oxygen. The hydrogen enters the hydrogen separator together with the electrolyte, and the oxygen enters the oxygen separator together with the electrolyte. The hydrogen is discharged through the upper end of the hydrogen separator, and the oxygen is discharged through the upper end of the oxygen separator. The lower ends of the oxygen separator and the hydrogen separator are the electrolyte outlets. After flowing through the post-processing unit, the electrolyte is pumped into the electrolytic cell by a circulation pump for circulation.

[0068] During the electrolysis process, the suspended iron settles to the bottom of the suspended iron settling device; according to a certain period, the external magnetic device is moved up and down below the liquid inlet, the sewage outlet is opened, and the sewage discharge operation is carried out.

[0069] Compared with the prior art, the present invention has the following beneficial effects:

[0070] The use of the iron suspension sedimentation device provided by the present invention can solve the problem of iron suspension blocking part of the micropores of the diaphragm and causing the diaphragm resistance to increase, solve the problem of increased electrolysis energy consumption and decreased cathode hydrogen evolution performance, and improve the performance and service life of the water electrolysis hydrogen production device system. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 A schematic diagram of the structure of the iron suspension sedimentation device provided in Example 1;

[0072] Figure 2 A schematic diagram of the structure of the water electrolysis hydrogen production device system provided in Example 2;

[0073] Figure 3 A schematic diagram of the structure of the water electrolysis hydrogen production device system provided in Example 3;

[0074] Figure 4 This is a schematic diagram of the structure of the water electrolysis hydrogen production device system provided in Example 4.

[0075] Among them: 1, iron suspension sedimentation device; 11, baffle plate; 12, liquid outlet baffle plate; 13, liquid inlet; 14, liquid outlet; 15, exhaust port; 16, external magnetic device; 17, sewage outlet; 2, electrolytic cell; 3, hydrogen separator; 4, oxygen separator; 5, cooling device; 6, filtering device. DETAILED DESCRIPTION

[0076] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0077] Example 1

[0078] This embodiment provides a Figure 1The suspended iron sedimentation device 1 shown comprises a sedimentation chamber;

[0079] The sedimentation chamber is divided into an inlet sedimentation chamber and an outlet sedimentation chamber by a baffle 11; the inlet sedimentation chamber is connected to the top of the outlet sedimentation chamber; the volume of the inlet sedimentation chamber is 1.2 times the volume of the outlet sedimentation chamber;

[0080] A sewage outlet 17 is provided at the bottom of the liquid inlet sedimentation chamber and the liquid outlet sedimentation chamber;

[0081] The side wall of the liquid inlet sedimentation chamber is provided with a liquid inlet 13, and the side wall of the liquid outlet sedimentation chamber is provided with a liquid outlet 14; the heights of the liquid inlet 13 and the liquid outlet 14 are both lower than the height of the baffle 11, and the height of the liquid outlet 14 is higher than the height of the liquid inlet 13;

[0082] A liquid outlet baffle 12 is obliquely arranged in the liquid outlet sedimentation chamber; one end of the liquid outlet baffle 12 is connected to the side wall above the liquid outlet 14 , and the other end extends to the bottom of the liquid outlet 14 .

[0083] The settling chamber of the present invention comprises a shell and a top cover; the top cover is flange-connected to the shell; the exhaust port 15 is arranged on the top cover, and an exhaust valve is arranged at the exhaust port 15 .

[0084] The settling chamber is provided with a pressure sensor (not shown in the figure). The pressure sensor is electrically connected to an external control device, and the pressure sensor transmits the collected pressure signal to the control device, and the control device controls the opening and closing of the exhaust valve by comparing the set pressure with the collected pressure.

[0085] The iron suspension sedimentation device 1 is further provided with an external magnetic attraction device 16, which is arranged outside the sedimentation chamber and below the liquid inlet 13;

[0086] The outer wall of the sedimentation chamber is provided with a heat-insulating material, and a temperature sensor (not shown in the figure) for measuring the temperature of the electrolyte in the sedimentation chamber is provided in the sedimentation chamber; the iron suspension sedimentation device 1 also includes a liquid level measuring device (not shown in the figure) for detecting the liquid level height in the sedimentation chamber.

[0087] Example 2

[0088] This embodiment provides a Figure 2 The water electrolysis hydrogen production device system shown includes an electrolyzer 2, a hydrogen separator 3, an oxygen separator 4 and a post-processing unit;

[0089] The post-processing unit comprises an iron suspension sedimentation device 1, a cooling device 5 and a filtering device 6 connected in sequence;

[0090] The liquid outlets of the hydrogen separator 3 and the oxygen separator 4 are connected to the liquid inlet of the iron suspension sedimentation device 1;

[0091] The liquid outlet of the filter device 6 is connected to the liquid inlet of the electrolytic cell 2;

[0092] The position of the iron suspension sedimentation device 1 is lower than the bottom of the oxygen separator 4 and the hydrogen separator 3 .

[0093] The water electrolysis hydrogen production device system also includes a circulation device for driving the electrolyte to flow, and the circulation device is a circulation pump;

[0094] When the water electrolysis hydrogen production device system is used, a DC power supply is used to power the electrolytic cell 2, and the electrolyte in the electrolytic cell 2 is electrolyzed to form hydrogen and oxygen; hydrogen enters the hydrogen separator 3 along with the electrolyte, and oxygen enters the oxygen separator 4 along with the electrolyte; hydrogen is discharged through the upper end of the hydrogen separator 3 for subsequent treatment; oxygen is discharged through the upper end of the oxygen separator 4 for subsequent treatment; the lower ends of the hydrogen separator 3 and the oxygen separator 4 are electrolyte outlets, which enter the post-processing unit for sedimentation treatment, cooling treatment and filtration treatment, and then flow into the electrolytic cell 2 for circulation under the transportation of the circulation device.

[0095] Example 3

[0096] This embodiment provides a Figure 3 The water electrolysis hydrogen production device system shown includes an electrolyzer 2, a hydrogen separator 3, an oxygen separator 4 and a post-processing unit;

[0097] The post-processing unit comprises a cooling device 5, an iron suspension sedimentation device 1 and a filtering device 6 connected in sequence;

[0098] The liquid outlets of the hydrogen separator 3 and the oxygen separator 4 are connected to the liquid inlet of the cooling device 5;

[0099] The liquid outlet of the cooling device 5 is connected to the liquid inlet of the electrolytic cell 2;

[0100] The position of the iron suspension sedimentation device 1 is lower than the bottom of the oxygen separator 4 and the hydrogen separator 3 .

[0101] The water electrolysis hydrogen production device system also includes a circulation device for driving the electrolyte to flow, and the circulation device is a circulation pump;

[0102] When the water electrolysis hydrogen production device system is used, a DC power supply is used to power the electrolytic cell 2, and the electrolyte in the electrolytic cell 2 is electrolyzed to form hydrogen and oxygen; hydrogen enters the hydrogen separator 3 along with the electrolyte, and oxygen enters the oxygen separator 4 along with the electrolyte; hydrogen is discharged through the upper end of the hydrogen separator 3 for subsequent treatment; oxygen is discharged through the upper end of the oxygen separator 4 for subsequent treatment; the lower ends of the hydrogen separator 3 and the oxygen separator 4 are electrolyte outlets, which enter the post-processing unit for cooling treatment, sedimentation treatment and filtration treatment, and then flow into the electrolytic cell 2 for circulation under the transportation of the circulation device.

[0103] Example 4

[0104] This embodiment provides a Figure 4 The water electrolysis hydrogen production device system shown includes an electrolyzer 2, a hydrogen separator 3, an oxygen separator 4 and a post-processing unit;

[0105] The post-processing unit comprises a cooling device 5, a filtering device 6 and an iron suspension sedimentation device 1 connected in sequence;

[0106] The liquid outlets of the hydrogen separator 3 and the oxygen separator 4 are connected to the liquid inlet of the cooling device 5;

[0107] The liquid outlet of the iron suspension sedimentation device 1 is connected to the liquid inlet of the electrolytic cell 2;

[0108] The position of the iron suspension sedimentation device 1 is lower than the bottom of the oxygen separator 4 and the hydrogen separator 3 .

[0109] The water electrolysis hydrogen production device system also includes a circulation device for driving the electrolyte to flow, and the circulation device is a circulation pump;

[0110] When the water electrolysis hydrogen production device system is used, a DC power supply is used to power the electrolytic cell 2, and the electrolyte in the electrolytic cell 2 is electrolyzed to form hydrogen and oxygen; hydrogen enters the hydrogen separator 3 along with the electrolyte, and oxygen enters the oxygen separator 4 along with the electrolyte; hydrogen is discharged through the upper end of the hydrogen separator 3 for subsequent treatment; oxygen is discharged through the upper end of the oxygen separator 4 for subsequent treatment; the lower ends of the hydrogen separator 3 and the oxygen separator 4 are electrolyte outlets, which enter the post-processing unit for cooling treatment, filtering treatment and sedimentation treatment, and then flow into the electrolytic cell 2 for circulation under the transportation of the circulation device.

[0111] Application Example 1

[0112] This application example provides a method for applying the water electrolysis hydrogen production device system provided in Example 2. When applied, a branch is set at the liquid inlet and liquid outlet of the iron suspended matter settling device to control the electrolysis chamber without using the iron suspended matter settling device;

[0113] The anode in electrolytic cell 2 is a nickel-iron alloy oxygen evolution electrode, the cathode is a commercial porous nickel cathode (N6), and the diaphragm is a commercial polyphenylene sulfide diaphragm (6165A4 SD3002);

[0114] The method comprises the following steps:

[0115] (1) a KOH electrolyte with a concentration of 30 wt% and a temperature of 85° C. is prepared in an alkali tank, and the electrolyte is pumped into an iron suspension sedimentation device 1 (300 L) by a circulation pump to ensure that the inlet flow rate of the iron suspension sedimentation device 1 is consistent with the outlet flow rate, and then the inlet and outlet of the iron suspension sedimentation device 1 are closed;

[0116] (2) The electrolyte is pumped into the water electrolysis hydrogen production device system through a circulation pump at a flow rate of 600 L / h, so that the liquid levels of the hydrogen separator 3 and the oxygen separator 4 reach the process height (300 L); the electrolyte flows through the branch line so that the iron suspension sedimentation device 1 does not participate in the alkali solution circulation;

[0117] (3) Turn on the water electrolysis system and start electrolysis with a current density of 6000A / m 2 The electrolyte in the electrolytic cell 2 is electrolyzed to form hydrogen and oxygen. The hydrogen enters the hydrogen separator 3 together with the electrolyte, and the oxygen enters the oxygen separator 4 together with the electrolyte. The hydrogen is discharged through the upper end of the hydrogen separator 3, and the oxygen is discharged through the upper end of the oxygen separator 4; the lower ends of the oxygen separator 4 and the hydrogen separator 3 are the electrolyte outlets, and after flowing through the cooling device 5 and the filtering device 6, the electrolyte is pumped into the electrolytic cell 2 by the circulation pump for circulation; sampling is performed after 12 hours of electrolysis, and the mass concentration of suspended iron in the electrolyte is determined to be 1.0904g / L;

[0118] (4) The electrolyte is then passed through the iron suspension settling device 1. After the electrolyte is circulated and electrolyzed for 12 hours, a sample is taken. The mass concentration of the iron suspension in the electrolyte is measured to be 0.1243 g / L. Considering the influence of the fresh electrolyte in the iron suspension settling device 1, the removal rate of the iron suspension reaches 77.2%.

[0119] In this embodiment, when the iron suspended matter sedimentation device 1 was not used, the voltage of the electrolytic cell 2 during sampling increased by 0.35V; when the iron suspended matter sedimentation device 1 was used, the voltage in the electrolytic cell 2 was stable during sampling, and during the subsequent 72h test time, the voltage in the electrolytic cell 2 increased by <0.1V, which was within the normal fluctuation range.

[0120] Application Example 2

[0121] This application example provides a method for applying the water electrolysis hydrogen production device system provided in Example 3. When applied, a branch is set at the liquid inlet and liquid outlet of the iron suspended matter settling device to control the comparison of the electrolysis chamber without using the iron suspended matter settling device;

[0122] The anode in electrolytic cell 2 is a nickel-iron alloy oxygen evolution electrode, the cathode is a commercial porous nickel cathode (N6), and the diaphragm is a commercial polyphenylene sulfide diaphragm (6165A4 SD3002);

[0123] The method comprises the following steps:

[0124] (1) a KOH electrolyte with a concentration of 30 wt% and a temperature of 85° C. is prepared in an alkali tank, and the electrolyte is pumped into an iron suspension sedimentation device 1 (300 L) by a circulation pump to ensure that the inlet flow rate of the iron suspension sedimentation device 1 is consistent with the outlet flow rate, and then the inlet and outlet of the iron suspension sedimentation device 1 are closed;

[0125] (2) The electrolyte is pumped into the water electrolysis hydrogen production device system through a circulation pump at a flow rate of 400 L / h, so that the liquid levels of the hydrogen separator 3 and the oxygen separator 4 reach the process height (300 L); the electrolyte flows through the branch line so that the iron suspension sedimentation device 1 does not participate in the alkali solution circulation;

[0126] (3) Turn on the water electrolysis system and start electrolysis with a current density of 6000A / m 2 The electrolyte in the electrolytic cell 2 is electrolyzed to form hydrogen and oxygen. The hydrogen enters the hydrogen separator 3 together with the electrolyte, and the oxygen enters the oxygen separator 4 together with the electrolyte. The hydrogen is discharged through the upper end of the hydrogen separator 3, and the oxygen is discharged through the upper end of the oxygen separator 4. The lower ends of the oxygen separator 4 and the hydrogen separator 3 are the electrolyte outlets. After passing through the cooling device 5 and the filtering device 6, the electrolyte is pumped into the electrolytic cell 2 by the circulation pump for circulation. After 12 hours of electrolysis, sampling is carried out, and the mass concentration of suspended iron in the electrolyte is measured to be 1.0716 g / L.

[0127] (4) The electrolyte is then passed through the iron suspension settling device 1. After the electrolyte is circulated and electrolyzed for 12 hours, a sample is taken. The mass concentration of the iron suspension in the electrolyte is measured to be 0.1061 g / L. Considering the influence of the fresh electrolyte in the iron suspension settling device 1, the removal rate of the iron suspension reaches 80.2%.

[0128] In this application example, when the iron suspended matter sedimentation device 1 was not used, the voltage of the electrolytic cell 2 during sampling increased by 0.35V; when the iron suspended matter sedimentation device 1 was used, the voltage in the electrolytic cell 2 was stable during sampling, and during the subsequent 72h test time, the voltage in the electrolytic cell 2 increased by <0.05V, which was within the normal fluctuation range.

[0129] Application Example 3

[0130] This application example provides a method for applying the water electrolysis hydrogen production device system provided in Example 4. When applied, a branch is set at the liquid inlet and liquid outlet of the iron suspended matter settling device to control the comparison of the electrolysis chamber without using the iron suspended matter settling device;

[0131] The anode in electrolytic cell 2 is a nickel-iron alloy oxygen evolution electrode, the cathode is a commercial porous nickel cathode (N6), and the diaphragm is a commercial polyphenylene sulfide diaphragm (6165A4 SD3002);

[0132] The method comprises the following steps:

[0133] (1) a KOH electrolyte with a concentration of 30 wt% and a temperature of 90° C. is prepared in an alkali tank, and the electrolyte is pumped into an iron suspension sedimentation device 1 (300 L) by a circulation pump to ensure that the inlet flow rate of the iron suspension sedimentation device 1 is consistent with the outlet flow rate, and then the inlet and outlet of the iron suspension sedimentation device 1 are closed;

[0134] (2) The electrolyte is pumped into the water electrolysis hydrogen production device system through a circulation pump at a flow rate of 700 L / h, so that the liquid levels of the hydrogen separator 3 and the oxygen separator 4 reach the process height (300 L); the electrolyte flows through the branch line so that the iron suspension sedimentation device 1 does not participate in the alkali solution circulation;

[0135] (3) Turn on the water electrolysis system and start electrolysis with a current density of 6500A / m 2 The electrolyte in the electrolytic cell 2 is electrolyzed to form hydrogen and oxygen. The hydrogen enters the hydrogen separator 3 together with the electrolyte, and the oxygen enters the oxygen separator 4 together with the electrolyte. The hydrogen is discharged through the upper end of the hydrogen separator 3, and the oxygen is discharged through the upper end of the oxygen separator 4; the lower ends of the oxygen separator 4 and the hydrogen separator 3 are the electrolyte outlets, and after flowing through the cooling device 5 and the filtering device 6, the electrolyte is pumped into the electrolytic cell 2 by the circulation pump for circulation; sampling is performed after 12 hours of electrolysis, and the mass concentration of suspended iron in the electrolyte is determined to be 1.1167g / L;

[0136] (4) The electrolyte is then passed through the iron suspension settling device 1. After the electrolyte is circulated and electrolyzed for 12 hours, a sample is taken. The mass concentration of the iron suspension in the electrolyte is measured to be 0.1150 g / L. Considering the influence of the fresh electrolyte in the iron suspension settling device 1, the removal rate of the iron suspension reaches 79.41%.

[0137] In this application example, when the iron suspended matter sedimentation device 1 was not used, the voltage of the electrolytic cell 2 during sampling increased by 0.35V; when the iron suspended matter sedimentation device 1 was used, the voltage in the electrolytic cell 2 was stable during sampling, and during the subsequent 72h test time, the voltage in the electrolytic cell 2 increased by <0.05V, which was within the normal fluctuation range.

[0138] Comparative application example 1

[0139] This comparative application example provides a method for applying the water electrolysis hydrogen production device system provided in Example 4. When applied, a branch is set at the liquid inlet and liquid outlet of the iron suspended matter settling device 1 to control the electrolysis chamber without using the iron suspended matter settling device 1.

[0140] The anode in electrolytic cell 2 is a nickel-iron alloy oxygen evolution electrode, the cathode is a commercial porous nickel cathode (N6), and the diaphragm is a commercial polyphenylene sulfide diaphragm (6165A4 SD3002);

[0141] The method comprises the following steps:

[0142] (1) a KOH electrolyte with a concentration of 30 wt% and a temperature of 90° C. is prepared in an alkali tank, and the electrolyte is pumped into an iron suspension sedimentation device 1 (300 L) by a circulation pump to ensure that the inlet flow rate of the iron suspension sedimentation device 1 is consistent with the outlet flow rate, and then the inlet and outlet of the iron suspension sedimentation device 1 are closed;

[0143] (2) The electrolyte is pumped into the water electrolysis hydrogen production device system through a circulation pump at a flow rate of 700 L / h, so that the liquid levels of the hydrogen separator 3 and the oxygen separator 4 reach the process height (300 L); the electrolyte flows through the branch line so that the iron suspension sedimentation device 1 does not participate in the alkali solution circulation;

[0144] (3) Turn on the water electrolysis system and start electrolysis with a current density of 6500A / m 2 The electrolyte in the electrolytic cell 2 is electrolyzed to form hydrogen and oxygen. The hydrogen enters the hydrogen separator 3 together with the electrolyte, and the oxygen enters the oxygen separator 4 together with the electrolyte. The hydrogen is discharged through the upper end of the hydrogen separator 3, and the oxygen is discharged through the upper end of the oxygen separator 4; the lower ends of the oxygen separator 4 and the hydrogen separator 3 are the electrolyte outlets, and after flowing through the cooling device 5 and the filtering device 6, the electrolyte is pumped into the electrolytic cell 2 by the circulation pump for circulation; sampling is performed after 12 hours of electrolysis, and the mass concentration of suspended iron in the electrolyte is determined to be 1.1054 g / L;

[0145] (4) The suspended iron sedimentation device 1 was not used. The electrolyte was sampled after 12 hours of circulating electrolysis. The mass concentration of suspended iron in the electrolyte was measured to be 1.1110 g / L, which increased by 0.0056 g / L.

[0146] In this comparative application example, when the iron suspended matter sedimentation device 1 was not used, the voltage of the electrolytic cell 2 during sampling increased by 0.35V; during the subsequent 84h test time, the voltage in the electrolytic cell 2 increased by more than 0.2V, and the voltage increase was relatively high.

[0147] In summary, the use of the iron suspension sedimentation device provided by the present invention can solve the problem of iron suspension blocking some micropores of the diaphragm and causing increased diaphragm resistance, solve the problem of increased electrolysis energy consumption and decreased cathode hydrogen evolution performance, and improve the performance and service life of the water electrolysis hydrogen production device system.

[0148] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. An iron suspension sedimentation device, characterized in that: The iron suspension sedimentation device comprises a sedimentation chamber; The sedimentation chamber is divided into a liquid inlet sedimentation chamber and a liquid outlet sedimentation chamber by a baffle plate; the top of the liquid inlet sedimentation chamber is connected to the top of the liquid outlet sedimentation chamber; The side wall of the liquid inlet sedimentation chamber is provided with a liquid inlet, and the side wall of the liquid outlet sedimentation chamber is provided with a liquid outlet; the heights of the liquid inlet and the liquid outlet are both lower than the height of the baffle, and the height of the liquid outlet is higher than the height of the liquid inlet; A liquid outlet baffle is obliquely arranged in the liquid outlet sedimentation chamber; one end of the liquid outlet baffle is connected to the side wall above the liquid outlet, and the other end extends to the bottom of the liquid outlet.

2. The iron suspension sedimentation device according to claim 1, characterized in that: The top of the settling chamber is provided with an exhaust port; The exhaust port is provided with an exhaust valve.

3. The iron suspension sedimentation device according to claim 1 or 2, characterized in that: The iron suspension sedimentation device is also provided with an external magnetic attraction device; The external magnetic attraction device is arranged outside the sedimentation chamber and below the liquid inlet.

4. The iron suspension sedimentation device according to any one of claims 1 to 3, characterized in that: The volume of the liquid inlet sedimentation chamber is greater than the volume of the liquid outlet sedimentation chamber; Preferably, a sewage outlet is provided at the bottom of the liquid inlet sedimentation chamber and / or the liquid outlet sedimentation chamber.

5. The iron suspension sedimentation device according to any one of claims 1 to 4, characterized in that: The outer wall of the settling chamber is provided with a heat-insulating material; Preferably, the material of the sedimentation chamber includes a corrosion-resistant material, and more preferably stainless steel or carbon steel with nickel-plated inner wall; Preferably, the suspended iron sedimentation device further comprises a liquid level measuring device; the liquid level measuring device is used to detect the liquid level height in the sedimentation chamber.

6. A water electrolysis hydrogen production device system, characterized in that: The water electrolysis hydrogen production device system comprises the iron suspension sedimentation device according to any one of claims 1-5.

7. The water electrolysis hydrogen production device system according to claim 6, characterized in that: The water electrolysis hydrogen production device system comprises an electrolyzer, a hydrogen separator, an oxygen separator and a post-processing unit; The post-processing unit comprises a cooling device, a filtering device and an iron suspension sedimentation device according to any one of claims 1 to 5; The two outlets of the electrolyzer are connected to the feed ports of the hydrogen separator and the oxygen separator through pipelines respectively; the liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the post-processing unit; and the liquid outlet of the post-processing unit is connected to the liquid inlet of the electrolyzer.

8. The water electrolysis hydrogen production device system according to claim 7, characterized in that: The post-processing unit comprises a cooling device, a filtering device and an iron suspension sedimentation device connected in sequence; The liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the cooling device; The liquid outlet of the iron suspension sedimentation device is connected to the liquid inlet of the electrolytic cell; or, The post-processing unit comprises a cooling device, an iron suspension sedimentation device and a filtering device connected in sequence; The liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the cooling device; The liquid outlet of the cooling device is connected to the liquid inlet of the electrolytic cell; or, The post-processing unit includes an iron suspension sedimentation device, a cooling device and a filtering device connected in sequence; The liquid outlets of the hydrogen separator and the oxygen separator are connected to the liquid inlet of the iron suspension sedimentation device; The liquid outlet of the filtering device is connected to the liquid inlet of the electrolytic cell.

9. The water electrolysis hydrogen production device system according to claim 7 or 8, characterized in that: The position of the iron suspension sedimentation device is lower than the bottom of the oxygen separator and the hydrogen separator.

10. An application of the water electrolysis hydrogen production device system according to any one of claims 6 to 9, characterized in that: During the process of producing hydrogen by electrolyzing water, the suspended iron sedimentation device is used to remove suspended iron in the electrolyzed water.

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