System for producing Cl2 and H2 through membrane-free electrolysis of industrial waste hydrochloric acid

Abstract

The utility model belongs to the technical field of chlorine and hydrogen production by waste hydrochloric acid, and particularly relates to a system for producing Cl2 and H2 by membrane-free electrolysis of industrial waste hydrochloric acid, which comprises a membrane-free electrolysis system, a gas-liquid separation system and a chlorine and hydrogen separation system, the diaphragm-free electrolysis system, the gas-liquid separation system and the chlorine-hydrogen separation system are sequentially communicated through an energy dissipation pipeline, and the energy dissipation pipeline is filled with a porous metal wire mesh; a non-gas-liquid-phase co-flow area of each single device in the gas-liquid separation system and the chlorine-hydrogen separation system is filled with a porous metal wire mesh; the whole system is grounded. According to the system, liquid chlorine and fuel cell grade hydrogen products can be obtained, and meanwhile it is guaranteed that the whole system operates intrinsically safely and stably for a long period.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production from waste hydrochloric acid, and in particular to a system for producing Cl2 and H2 by membrane-free electrolysis of industrial waste hydrochloric acid. Background Art

[0002] For dilute hydrochloric acid as an industrial by-product, wet diaphragm electrolysis is mainly used at present, and the technology can be divided into traditional diaphragm electrolysis and oxygen cathode electrolysis. There are three defects in the existing technology of electrolysis using the diaphragm method:

[0003] First, the electrolysis energy consumption increases significantly. The resistance of the diaphragm itself and the resistance brought by sealing both ends of the diaphragm to increase the electrode spacing will cause a significant increase in the cell voltage.

[0004] Second, the diaphragm itself is expensive, the requirements for component sealing and assembly accuracy are high, and the service life of the diaphragm is limited. If the diaphragm in any electrolysis cell ruptures, the whole needs to be replaced, resulting in a significant increase in the overall equipment investment and operation cost.

[0005] Third, the diaphragm is sensitive to impurities in the electrolyte. Once the diaphragm is blocked, poisoned or swollen, it will cause an increase in the cell voltage and a decrease in the current efficiency, making the raw material liquid refining and impurity removal process flow complex, and the equipment investment and operation cost extremely high. Oxygen cathode electrolysis has a significant decrease in the cell voltage compared with traditional diaphragm electrolysis because hydrogen is not generated on the cathode side. However, this method has higher requirements for the refining of the raw material liquid, the oxygen cathode structure is more complex, the manufacturing and operation and maintenance costs are high, and high-purity oxygen is required at the same time, which additionally increases the operation cost, and the comprehensive cost of chlorine per unit product is still very high.

[0006] Therefore, it is necessary to develop a system for producing liquid chlorine and hydrogen by membrane-free electrolysis of industrial waste hydrochloric acid with low cost. Summary of the Invention

[0007] The purpose of the present invention is to provide a system for producing Cl2 and H2 by membrane-free electrolysis of industrial waste hydrochloric acid with low cost.

[0008] To achieve the above purpose, the present invention provides the following technical solution: A system for producing Cl2 and H2 by membrane-free electrolysis of industrial waste hydrochloric acid, including a membrane-free electrolysis system, a gas-liquid separation system, and a chlorine-hydrogen separation system;

[0009] The membrane-free electrolysis system, the gas-liquid separation system, and the chlorine-hydrogen separation system are sequentially connected through an energy dissipation pipeline, and the energy dissipation pipeline is filled with a porous metal wire mesh;

[0010] The non-gas-liquid co-flow areas of each monomer device in the gas-liquid separation system and the chlorine-hydrogen separation system are filled with a porous metal wire mesh;

[0011] The whole system is grounded.

[0012] In order to solve a series of problems brought about by the diaphragm of the electrolytic cell in the prior art, the inventor came up with the idea of directly electrolyzing hydrochloric acid without a diaphragm. However, considering that the mixture gas produced by electrolyzing hydrochloric acid is a mixture of chlorine and hydrogen, and this mixture gas is an explosive gas, therefore, it is necessary to solve the problem of the operating safety of the entire system.

[0013] The inventor further studied and analyzed and learned that combustibles, oxidants, and energy are the three elements that constitute an explosion. Hydrogen and chlorine will undergo a rapid reaction with heat release and then explode under the influence of certain external conditions. The reaction between hydrogen and chlorine belongs to a chain radical reaction. Under the action of external factors such as heating, light, and electrostatic accumulation reaching the minimum ignition energy, the covalent bond breaks to generate free radicals, Cl2 decomposes into two Cl· free radicals, chain initiation occurs, the Cl· free radical reacts with H2 to generate HCl and H· free radicals, chain propagation occurs, and when the free radical chain reaction disappears, chain termination occurs.

[0014] The inventor further analyzed that if a mixture gas of chlorine and hydrogen produced by electrolyzing hydrochloric acid without a diaphragm is used, the first two elements (reductant and oxidant) in the three elements of explosion are satisfied. Therefore, the core of solving the operating safety problem lies in fundamentally eliminating the third element (energy). Through research, it is found that the energy of the system for producing Cl2 and H2 by electrolyzing hydrochloric acid mainly comes from the static electricity generated during the operation process and a very small amount of stray current that the electrolytic cell may bring.

[0015] Based on this, the inventor creatively connects the diaphragm-free electrolysis system, gas-liquid separation system, and chlorine-hydrogen separation system in sequence through an energy-dissipating pipeline. The energy-dissipating pipeline is filled with porous metal (such as titanium, platinum, palladium, etc.) wire mesh and carbon-based materials. Utilizing the good electrical conductivity and chlorine corrosion resistance characteristics of the porous metal wire mesh, any static electricity generated by the flow of hydrogen and chlorine in the pipeline and a very small amount of stray current that the electrolytic cell may bring are transmitted to the porous metal wire mesh, and then transmitted from the porous metal wire mesh to the pipeline wall to drain the static electricity and stray current to the ground, avoiding explosion.

[0016] At the same time, in the non-gas-liquid co-flow area of each monomer device in the gas-liquid separation system and the chlorine-hydrogen separation system of the present application, porous metal wire mesh is filled; to ensure that no explosion will occur in the above-mentioned devices.

[0017] In addition, all equipment, pipelines, pipeline components, electrical components, etc. in the entire system are strictly grounded in accordance with relevant design specifications to ensure that the grounding resistance is lower than 3Ω, so that any static electricity generated in the system or externally introduced charges can be instantaneously drained to the ground, and the chain propagation reaction of hydrogen and chlorine will not be caused, thereby ensuring the long-term stable operation of the intrinsically safe system.

[0018] The porous metal wire mesh is a porous metal titanium wire mesh, platinum wire mesh, palladium wire mesh, etc. with 150 - 320 meshes and good electrical and thermal conductivity.

[0019] Further, multiple sections of porous metal wire mesh are filled in the energy dissipation pipeline at an interval distance of 0 - 1 m, and the filling length of each section of porous metal wire mesh is 0.1 - 1 m.

[0020] The inventor found that when using porous metal wire mesh and carbon - based materials to fill the energy dissipation pipeline, when the filling interval distance of the filled porous metal wire mesh is within 1 m, the safety of the system can be guaranteed. That is, multiple sections of porous metal wire mesh are filled at a certain interval distance n (0 < n ≤ 1 m), or there is no interval distance between each section of porous metal wire mesh to ensure the safety of the system.

[0021] Preferably, multiple sections of porous metal wire mesh are filled in the energy dissipation pipeline at an interval distance of 1 m, and the filling length of each section of porous metal wire mesh is 1 m.

[0022] The electrolyzed hydrogen and chlorine are mixed with hydrochloric acid solution. Further, the gas - liquid separation system includes a gas - liquid separation tank and a mixed - gas dehumidification device;

[0023] The gas - phase outlet of the diaphragm - free electrolysis system is connected to the inlet of the gas - liquid separation tank through an energy dissipation pipeline, and the gas - phase outlet of the gas - liquid separation tank is connected to the inlet of the mixed - gas dehumidification device through an energy dissipation pipeline; Porous metal wire mesh is filled in the space between the liquid phase above and the wire mesh demister at the top of the gas - liquid separation tank.

[0024] The mixed - gas dehumidification device can be in ways such as chemical reaction dehumidification, physical adsorption, physical cooling, membrane dehumidification, etc. Preferably, the mixed - gas dehumidification device includes a concentrated sulfuric acid drying tower. The gas - phase outlet of the gas - liquid separation tank is connected to the gas - phase inlet at the bottom of the concentrated sulfuric acid drying tower, and the top of the concentrated sulfuric acid drying tower is connected to the chlorine - hydrogen separation system through an energy dissipation pipeline; The gas - phase inlet at the bottom of the concentrated sulfuric acid drying tower is arranged below the liquid level.

[0025] The chlorine - hydrogen separation system can be in ways such as physical condensation, membrane separation, or chemical reaction separation, etc. Preferably, the chlorine - hydrogen separation system includes a chlorine gas cooling tower. The gas - phase outlet of the mixed - gas dehumidification device is connected to the gas - phase inlet arranged below the liquid level in the chlorine gas cooling tower through an energy dissipation pipeline.

[0026] Further, it also includes a circulating liquid chlorine cooler. The first fluid inlet of the circulating liquid chlorine cooler is connected to the bottom of the chlorine gas cooling tower, and the first fluid outlet of the circulating liquid chlorine cooler is connected to the top of the chlorine gas cooling tower.

[0027] Further, it also includes a hydrogen purification system, which includes an alkali solution scrubbing tower and an adsorption drying tower. The gas phase inlet at the top of the chlorine cooling tower is connected to the gas phase inlet at the bottom of the alkali solution scrubbing tower; the gas phase inlet at the bottom of the alkali solution scrubbing tower is arranged below the liquid level. The top of the alkali solution scrubbing tower is connected to the bottom of the adsorption drying tower, and a hydrogen collection device is connected to the top of the adsorption drying tower.

[0028] Further, it also includes a first heat exchanger, a second heat exchanger and a third heat exchanger; the heat exchanger can be of types such as shell and tube heat exchanger, plate heat exchanger, jacketed heat exchanger, etc. The top of the chlorine cooling tower is connected to the first fluid inlet of the second heat exchanger; the first fluid outlet of the second heat exchanger is connected to the gas phase inlet arranged below the liquid level in the alkali solution scrubbing tower; the second fluid inlet of the second heat exchanger is connected to a circulating upper water inlet pipe, and the second fluid outlet of the second heat exchanger is connected to the second fluid inlet of the third heat exchanger;

[0029] The bottom of the chlorine cooling tower is also connected to the first fluid inlet of the third heat exchanger, and the first fluid outlet of the third heat exchanger is connected to a liquid chlorine collection device; the second fluid outlet of the third heat exchanger is connected to the second fluid inlet of the first heat exchanger;

[0030] The gas phase outlet of the gas-liquid separation tank is connected to the first fluid inlet of the first heat exchanger through an energy dissipation pipeline; the first fluid outlet of the first heat exchanger is connected to the gas phase inlet arranged below the liquid level in the concentrated sulfuric acid drying tower through an energy dissipation pipeline; the second fluid outlet of the first heat exchanger is connected to a circulating return water outlet pipe; the first fluid channel of the first heat exchanger is filled with a porous metal wire mesh.

[0031] Further, the diaphragm-free electrolysis system is composed of 1 to 30 small single electrolytic cells connected in parallel. Each single electrolytic cell is composed of N electrolytic chambers, where N≥1. Each electrolytic chamber includes an anode and a cathode, and the distance between the anode and the cathode is 0.1 to 1 mm; the anode and the cathode are composed of a titanium metal bipolar plate and an active coating coated on the titanium metal bipolar plate. The active coating includes two layers. The first active coatings of the anode and the cathode on the titanium metal bipolar plate are both titanium nitride, and the thickness of the first active coating is 0.5 to 5 μm. The second active coating of the anode on the titanium metal bipolar plate is one or more of titanium, iridium, ruthenium, osmium, rhodium, tantalum and their oxides. The second active coating of the cathode on the metal bipolar plate uses the same coating material as the anode or uses a platinum-palladium alloy coating, and the thickness of the second active coating is 0.1 to 5 μm.

[0032] Further, it also includes a raw material liquid tank, and the raw material liquid tank is connected to the membrane-free electrolytic cell.

[0033] The present invention has the following advantages and effects compared with the prior art:

[0034] (1) For the explosive mixture of chlorine and hydrogen gas generated by the diaphragm-free electrolysis of hydrochloric acid, the third element (energy) in the three elements of explosion is innovatively eliminated. Multiple safety measures are adopted, including filling porous metal wire meshes and carbon-based materials with good electrical and thermal conductivity in the connecting pipes between various devices, filling porous titanium wire meshes with good electrical and thermal conductivity in some devices, and setting the gas-phase inlets of the concentrated sulfuric acid drying tower and the liquid chlorine cooling and absorption tower below the liquid level in the tower. The grounding resistance of the whole system is controlled to be less than 3 Ω, etc., fully ensuring the intrinsically safe and long-term stable operation of the whole system.

[0035] (2) The diaphragm-free electrolysis of hydrochloric acid eliminates the thickness of the diaphragm layer and the sealing layer in terms of structure, without diaphragm resistance. At the same time, the distance between the anode and the cathode is almost zero, significantly reducing the total resistance between the cathode and the anode; and there is no diaphragm and complex sealing requirements, greatly reducing the raw material cost and assembly cost of the electrolytic cell. Compared with the diaphragm electrolytic cell, the overall structure is simple, the manufacturing cost is low, and the manufacturing time is short. There is no high operation and maintenance cost caused by diaphragm damage during the use process, and the service life of the diaphragm-free electrolysis system is more than 20 years.

[0036] (3) The mixture of chlorine and hydrogen gas generated by the diaphragm-free electrolysis of hydrochloric acid is treated by a series of integrated processes such as gas-liquid separation, heat exchange and cooling, concentrated sulfuric acid drying, liquid chlorine cooling and absorption, alkali solution dechlorination, and molecular sieve drying to obtain liquid chlorine and fuel cell-grade hydrogen products, with high separation efficiency and stable product quality. Description of the Drawings

[0037] Figure 1 The figure shows the system diagram of directly producing liquid chlorine and hydrogen from industrial waste hydrochloric acid by diaphragm-free electrolysis in Example 1;

[0038] Icon: 1 - raw material liquid tank, 2 - transfer pump, 3 - diaphragm-free electrolysis system, 4 - gas-liquid separation tank, 5 - first heat exchanger, 6 - concentrated sulfuric acid drying tower, 7 - chlorine cooling tower, 8 - second heat exchanger, 9 - alkali solution scrubbing tower, 10 - adsorption drying tower, 11 - circulating liquid chlorine cooler, 12 - third heat exchanger, 13 - electrolysis power supply. Detailed Embodiments

[0039] The following further describes the system for directly producing liquid chlorine and hydrogen from industrial waste hydrochloric acid by diaphragm-free electrolysis of the present invention in combination with specific embodiments, but the embodiments of the present invention are not limited thereto.

[0040] Example 1

[0041] This example provides a system for directly producing liquid chlorine and hydrogen from industrial waste hydrochloric acid by diaphragm-free electrolysis, as shown in the attached Figure 1 figure:

[0042] It includes a raw material liquid tank 1, a transfer pump 2, a diaphragm-free electrolysis system 3, a gas-liquid separation tank 4, a first heat exchanger 5, a concentrated sulfuric acid drying tower 6, a chlorine gas cooling tower 7, a second heat exchanger 8, a circulating liquid chlorine cooler 11, a third heat exchanger 12, an alkali solution scrubbing tower 9, an adsorption drying tower 10, and an electrolysis power supply 13;

[0043] The raw material liquid tank 1 is connected to the diaphragm-free electrolysis system 3, and the gas-phase outlet of the diaphragm-free electrolysis system 3 is connected to the inlet of the gas-liquid separation tank 4 through an energy dissipation pipeline; the gas-phase outlet of the gas-liquid separation tank 4 is connected to the tube-side inlet of the first heat exchanger 5 through an energy dissipation pipeline, and the tube-side outlet of the first heat exchanger 5 is connected to the gas-phase inlet at the bottom of the concentrated sulfuric acid drying tower 6 through an energy dissipation pipeline, and the gas-phase inlet of the concentrated sulfuric acid drying tower 6 is arranged below the liquid level; the gas-phase outlet at the top of the concentrated sulfuric acid drying tower 6 is connected to the gas-phase inlet at the bottom of the chlorine gas cooling tower 7 through an energy dissipation pipeline, and the gas-phase inlet of the chlorine gas cooling tower 7 is arranged below the liquid level; the liquid-phase outlet at the bottom of the chlorine gas cooling tower 7 is respectively connected to the tube-side inlet of the circulating liquid chlorine cooler 11 and the tube-side inlet of the third heat exchanger 12; the tube-side outlet of the circulating liquid chlorine cooler 11 is connected to the top of the chlorine gas cooling tower 7, and the gas-phase outlet at the top of the chlorine gas cooling tower 7 is connected to the tube-side inlet of the second heat exchanger 8 through an energy dissipation pipeline; the tube-side outlet of the second heat exchanger 8 is connected to the gas-phase inlet at the bottom inside the alkali solution scrubbing tower 9 through an energy dissipation pipeline, and the gas-phase inlet of the alkali solution scrubbing tower 9 is arranged below the liquid level; the gas-phase outlet at the top of the alkali solution scrubbing tower 9 is connected to the bottom of the adsorption drying tower 10, and a hydrogen gas collection device is connected to the top of the adsorption drying tower 10.

[0044] The circulating cooling water inlet pipe is sequentially connected to the shell-side of the second heat exchanger 8, the shell-side of the third heat exchanger 12, and the shell-side of the first heat exchanger 5 through pipelines, and the circulating water is recovered from the shell-side outlet of the first heat exchanger 5.

[0045] The shell-side of the circulating liquid chlorine cooler 11 is connected to a liquid chlorine supply system.

[0046] The electrolysis power supply 13 is connected to the diaphragm-free electrolysis system 3 through a copper cable to provide electrical energy for hydrochloric acid electrolysis.

[0047] In the energy dissipation pipelines between the diaphragm-free electrolysis system 3, the gas-liquid separation tank 4, the first heat exchanger 5, the concentrated sulfuric acid drying tower 6, the chlorine gas cooling tower 7, the second heat exchanger 8, and the alkali solution scrubbing tower 9, porous metal meshes are filled.

[0048] To ensure absolute safety, porous metal meshes are also filled in the space between the liquid phase above the top of the gas-liquid separation tank 4 and the wire mesh demister at the top, the tube-side of the first heat exchanger 5, and the tube-side of the second heat exchanger 8.

[0049] In the diaphragm-free electrolysis system 3, concentrated sulfuric acid drying tower 6, and chlorine cooling tower 7, gas-liquid co-flow exists, there is no electrostatic accumulation, and chain initiation reactions will not occur. These devices are intrinsically safe. The gas-phase inlets of the concentrated sulfuric acid drying tower 6 and chlorine cooling tower 7 are both located below the liquid level in the tower to ensure the intrinsic safety of the mixture of hydrogen and chlorine entering the tower.

[0050] For all equipment, pipelines, pipeline components, electrical components, etc. within the entire system, grounding measures are strictly implemented in accordance with relevant design specifications to ensure that the grounding resistance is less than 3 Ω, so that any static electricity generated within the system or externally introduced charges can be instantaneously drained to the ground, and the chain transfer reaction between hydrogen and chlorine will not be caused, thereby ensuring the long-term stable operation of the intrinsically safe protection system.

[0051] The porous metal wire mesh 14 is a 150-mesh porous titanium wire mesh with good electrical and thermal conductivity.

[0052] The adsorption drying tower 10 uses molecular sieves for adsorption dehydration.

[0053] According to the pipeline length, multi-sections of porous metal wire mesh are filled in the energy dissipation pipeline at an interval of 1 m, and the filling length of each section of porous metal wire mesh is 1 m.

[0054] The diaphragm-free electrolysis system is composed of 10 small individual electrolytic cells connected in parallel. Each individual electrolytic cell is composed of 10 electrolytic chambers. Each electrolytic chamber includes an anode and a cathode. The anodes and cathodes of the diaphragm-free electrolysis system both use titanium metal bipolar plates. The first active coatings on the anodes and cathodes of the bipolar plates are titanium nitride, with a coating thickness of 3 μm. The second active coatings on the anodes and cathodes of the bipolar plates are both ruthenium oxide, with a coating thickness of 1 μm. The distance between the anode and the cathode is 0.3 mm.

[0055] The inner wall of the tank body of the diaphragm-free electrolysis system in contact with the electrolyte uses a non-metallic lining material that can withstand the corrosion of strongly reducing media such as HCl, Cl2, H2, and HClO, and the tank body itself uses an economical material such as carbon steel.

[0056] The working process of the system in this embodiment is as follows: The waste hydrochloric acid with a concentration of 25 - 31 wt% generated from the hydrochloric acid absorption system directly enters the raw material liquid tank 1 for buffering, and after the concentration is adjusted to 15 - 25%, it is pressurized by the transfer pump 2 to 0.6 MPa.G and sent into the diaphragm-free electrolysis system 3 for electrolysis. Chlorine gas is generated at the anode and hydrogen gas is generated at the cathode; The mixed gas formed by chlorine gas and hydrogen gas and the entrained dilute hydrochloric acid are sent to the gas-liquid separation tank 4 together. Under the action of the gravity of the gas-liquid density difference, the separated dilute hydrochloric acid is mixed with the dilute hydrochloric acid generated by the diaphragm-free electrolysis system 3 and then returned to the dilute hydrochloric acid recycling absorption system; The mixed gas after liquid separation is heat-exchanged and cooled to 20 °C with the circulating water pre-cooled by the second heat exchanger 8 and the third heat exchanger 12 in the first heat exchanger 5, and the water generated by condensation is separated; Then it enters the concentrated sulfuric acid (content 98%) drying tower to further remove the water in the mixed gas to 15 ppmv; The dehydrated mixed gas enters the chlorine gas cooling tower 7 to reduce the temperature of the mixed gas to -80 °C. The chlorine content in the non-condensable hydrogen gas is 0.96 vol%. Utilizing the large boiling point difference between chlorine gas and hydrogen gas, through liquid chlorine condensation, the high-efficiency separation of chlorine gas and hydrogen gas in the mixed gas is realized. Most of the liquid chlorine sent out from the bottom of the chlorine gas cooling tower 7 is further cooled by the circulating liquid chlorine cooler 11 and then recycled back to the top of the chlorine gas cooling tower 7. The remaining liquid chlorine exchanges heat and recovers the cold energy with the circulating water pre-cooled by the second heat exchanger 8 in the third heat exchanger 12 and then the liquid chlorine product is sent out; The hydrogen gas and trace amount of chlorine gas sent out from the top of the chlorine gas cooling tower 7 exchange heat and recover the cold energy with the circulating water in the second heat exchanger 8 and are sent into the caustic solution scrubbing tower 9. The chlorine gas in the hydrogen gas is removed by reacting with the caustic solution. The hydrogen gas after chlorine removal by the caustic solution is sent to the adsorption drying tower 10. Under the selective adsorption and dehydration action of the molecular sieve material, the water and extremely trace amount of chlorine in the hydrogen gas are removed to obtain the fuel cell grade hydrogen gas product.

[0057] The content of the liquid chlorine product obtained after the mixed gas electrolyzed in Example 1 is processed by gas-liquid separation, heat exchange and cooling, concentrated sulfuric acid drying, liquid chlorine cooling, etc. is ≥ 99.8%, meeting the industrial liquid chlorine standard (GB / T 5138-2021). The crude hydrogen gas sent out from the top of the chlorine gas cooling tower is further processed by heat exchange and reheating, caustic solution dechlorination, adsorption drying, etc. The content of the obtained hydrogen gas product is ≥ 99.999%, meeting the requirements of chemical synthesis grade, fuel cell grade, and high purity grade.

[0058] In summary, the industrial waste hydrochloric acid membrane-free electrolysis system for producing liquid chlorine and hydrogen gas in this application obtains liquid chlorine and fuel cell grade hydrogen gas products through membrane-free electrolysis, and at the same time ensures the intrinsically safe long-term stable operation of the entire system.

Claims

1. A system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid, characterized in that: It includes a diaphragmless electrolysis system, a gas-liquid separation system and a chlorine-hydrogen separation system; The diaphragmless electrolysis system, the gas-liquid separation system and the chlorine-hydrogen separation system are sequentially connected through an energy dissipation pipeline, and the energy dissipation pipeline is filled with a porous metal wire mesh; The non-gas-liquid co-flow area of ​​each monomer device in the gas-liquid separation system and the chlorine-hydrogen separation system is filled with a porous metal wire mesh; The entire system is grounded.

2. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 1, characterized in that: The energy dissipation pipe is filled with multiple sections of porous metal wire mesh at intervals of 0 to 1 m, and the filling length of each section of the porous metal wire mesh is 0.1 to 1 m.

3. A system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to any one of claims 1 to 2, characterized in that: The gas-liquid separation system comprises a gas-liquid separation tank and a mixed gas dehumidification device; The gas phase outlet of the diaphragmless electrolysis system is connected to the inlet of the gas-liquid separation tank through an energy dissipation pipeline, and the gas phase outlet of the gas-liquid separation tank is connected to the inlet of the mixed gas dehumidification device through an energy dissipation pipeline; the space above the liquid phase of the gas-liquid separation tank and between the wire mesh demister on the top is filled with a porous metal wire mesh.

4. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 3, characterized in that: The mixed gas dehumidification device comprises a concentrated sulfuric acid drying tower, the gas phase outlet of the gas-liquid separation tank is connected with the gas phase inlet at the bottom of the concentrated sulfuric acid drying tower, the top of the concentrated sulfuric acid drying tower is connected with the chlorine-hydrogen separation system through an energy dissipation pipeline; the gas phase inlet at the bottom of the concentrated sulfuric acid drying tower is arranged below the liquid surface.

5. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 4, characterized in that: The chlorine-hydrogen separation system comprises a chlorine cooling tower, and the gas phase outlet of the mixed gas dehumidification device is connected with the gas phase inlet arranged below the liquid level in the chlorine cooling tower through an energy dissipation pipeline.

6. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 5, characterized in that: It also includes a circulating liquid chlorine cooler, wherein a first fluid inlet of the circulating liquid chlorine cooler is connected to the bottom of the chlorine gas cooling tower, and a first fluid outlet of the circulating liquid chlorine cooler is connected to the top of the chlorine gas cooling tower.

7. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 6, characterized in that: It also includes a hydrogen purification system, which includes an alkali liquid washing tower and an adsorption drying tower. The top of the chlorine cooling tower is connected to the gas phase inlet at the bottom of the alkali liquid washing tower; the gas phase inlet at the bottom of the alkali liquid washing tower is arranged below the liquid level, the top of the alkali liquid washing tower is connected to the bottom of the adsorption drying tower, and the top of the adsorption drying tower is connected to a hydrogen collection device.

8. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 7, characterized in that: Also includes a first heat exchanger, a second heat exchanger and a third heat exchanger; The top of the chlorine cooling tower is connected to the first fluid inlet of the second heat exchanger; the first fluid outlet of the second heat exchanger is connected to the gas phase inlet arranged below the liquid surface in the alkali liquid washing tower; the second fluid inlet of the second heat exchanger is connected to the circulating water inlet pipe, and the second fluid outlet of the second heat exchanger is connected to the second fluid inlet of the third heat exchanger; The bottom of the chlorine cooling tower is also connected to the first fluid inlet of the third heat exchanger, and the first fluid outlet of the third heat exchanger is connected to the liquid chlorine collecting device; the second fluid outlet of the third heat exchanger is connected to the second fluid inlet of the first heat exchanger; The gas phase outlet of the gas-liquid separation tank is connected to the first fluid inlet of the first heat exchanger through an energy dissipation pipe; the first fluid outlet of the first heat exchanger is connected to the gas phase inlet arranged below the liquid surface in the concentrated sulfuric acid drying tower through an energy dissipation pipe; the second fluid outlet of the first heat exchanger is connected to the circulating return water outlet pipe; the first fluid channel of the first heat exchanger is filled with a porous metal mesh.

9. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 8, characterized in that: The porous metal wire mesh is one or more of titanium, platinum and palladium.

10. The system for producing Cl2 and H2 by membraneless electrolysis of industrial waste hydrochloric acid according to claim 9, characterized in that: The diaphragmless electrolysis system is composed of 1 to 30 small single electrolytic cells connected in parallel, and a single electrolytic cell is composed of N electrolytic chambers, wherein N ≥ 1, and each electrolytic chamber includes an anode and a cathode, and the distance between the anode and the cathode is 0.1 to 1 mm; The anode and cathode are composed of a titanium metal bipolar plate and an active coating coated on the titanium metal bipolar plate, wherein the active coating includes two layers, wherein the first active coatings of the anode and cathode on the titanium metal bipolar plate are both titanium nitride, and the thickness of the first active coating is 0.5 to 5 μm, and the second active coating of the anode on the titanium metal bipolar plate is one or more of titanium, iridium, ruthenium, osmium, rhodium, tantalum and oxides thereof, and the second active coating of the cathode on the metal bipolar plate adopts the same coating material as that of the anode or adopts a platinum-palladium alloy coating, and the thickness of the second active coating is 0.1 to 5 μm.

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