Pure hydrogen shaft furnace and hydrogen circulation system thereof

Abstract

The utility model relates to a hydrogen circulation system which comprises a heating furnace, a thermochemical hydrogen production mechanism, a gas outlet pipeline connected with a top gas outlet of a shaft furnace, and a gas return pipeline connected with a reaction gas inlet of the shaft furnace, the gas outlet pipeline is connected with a heat source channel of an H2SO4 decomposer and a heat source channel of an HI decomposer of the thermochemical hydrogen production mechanism in series and then is connected with a heat exchange gas inlet of the heating furnace, and the gas return pipeline is connected with a heat exchange gas outlet of the heating furnace; and hydrogen produced by the thermochemical hydrogen production mechanism is supplied to the shaft furnace as reaction gas. Correspondingly, the utility model further provides a pure hydrogen shaft furnace provided with the hydrogen circulating system. According to the device, the gas outlet pipeline is connected with the heat source channel of the H2SO4 decomposer and the heat source channel of the HI decomposer in series, and part of heat energy of the furnace top gas is recycled for sulfur-iodine thermochemical hydrogen production, so that the high-temperature requirement of sulfur-iodine thermochemical hydrogen production is met, and hydrogen circulation of the pure hydrogen shaft furnace can be realized; the production cost of the pure hydrogen shaft furnace can be obviously reduced, and the production reliability of the pure hydrogen shaft furnace is improved.

Description

Technical Field

[0001] This utility model belongs to the field of vertical shaft furnace production technology, specifically relating to a hydrogen circulation system for a pure hydrogen vertical shaft furnace and a pure hydrogen vertical shaft furnace equipped with the hydrogen circulation system. Background Technology

[0002] The steel industry has long been a major contributor to carbon emissions, facing a significant challenge in carbon reduction. Currently, hydrogen-rich low-carbon smelting technology in blast furnaces and gas-based shaft furnace low-carbon smelting technology have been successfully applied in actual production, demonstrating their effectiveness in reducing carbon emissions in the steel industry. Pure hydrogen shaft furnace direct reduction technology is an even lower-carbon smelting technology; however, it requires a large amount of hydrogen as a reactant, resulting in high energy consumption and production costs, thus limiting its widespread adoption and application. Utility Model Content

[0003] This utility model relates to a hydrogen circulation system for a pure hydrogen vertical furnace and a pure hydrogen vertical furnace equipped with the hydrogen circulation system, which can at least solve some of the defects of the prior art.

[0004] This utility model relates to a hydrogen circulation system for a pure hydrogen vertical furnace, including a heating furnace, a thermochemical hydrogen production mechanism, an outlet gas pipe connected to the furnace top gas outlet of the vertical furnace, and a return gas pipe connected to the reaction gas inlet of the vertical furnace.

[0005] The thermochemical hydrogen production apparatus includes a reactor, an H2SO4 decomposer, and an HI decomposer. The H2SO4 decomposer is connected to the H2SO4 phase outlet of the reactor via an H2SO4 medium pipe, and the HI decomposer is connected to the HI phase outlet of the reactor via an HI medium pipe.

[0006] The outlet pipe is connected in series with the heat source channel of the H2SO4 decomposer and the heat source channel of the HI decomposer, and then connected to the heat exchange gas inlet of the heating furnace. The return gas pipe is connected to the heat exchange gas outlet of the heating furnace.

[0007] The HI decomposer is connected to a hydrogen storage tank, which is connected to the reaction gas inlet of the vertical furnace via a green hydrogen supply pipe.

[0008] As one embodiment, the outlet end of the green hydrogen supply pipe is connected in parallel to the gas outlet pipe.

[0009] As one embodiment, a first bypass pipe is also connected to the green hydrogen supply pipe. The first bypass pipe is directly connected to the vertical furnace. Control valves are respectively provided on the green hydrogen supply pipe and the first bypass pipe. The control valve on the green hydrogen supply pipe is located downstream of the bypass point of the first bypass pipe.

[0010] As one implementation method, a dehydrator is provided on the air outlet pipe, and the dehydrator is located upstream of the heat source channel connection area.

[0011] As one embodiment, the thermochemical hydrogen production device further includes a premixing tank, the mixing medium outlet of the premixing tank being connected to the reaction medium inlet of the reactor, and the water outlet of the dehydrator being connected to the water replenishment port of the premixing tank.

[0012] As one embodiment, the thermochemical hydrogen production apparatus further includes a premixing tank, the mixing medium outlet of which is connected to the reaction medium inlet of the reactor, and the heating furnace is equipped with a water collection pipe, which is connected to the water supply port of the premixing tank.

[0013] As one implementation method, a regenerator is also arranged on the gas outlet pipe, and the regenerator is located downstream of the heat source channel connection area.

[0014] As one implementation method, a second bypass pipe is also connected to the gas outlet pipe, and the outlet end of the second bypass pipe is connected to the fuel gas inlet of the heating furnace.

[0015] As one implementation method, a third bypass pipe is also connected to the gas outlet pipe. The two ends of the third bypass pipe are located upstream and downstream of the heat source channel connection area, respectively, and a bypass valve is provided on the third bypass pipe.

[0016] This utility model also relates to a pure hydrogen vertical furnace, which is equipped with a hydrogen circulation system as described above.

[0017] This utility model has at least the following beneficial effects:

[0018] In this invention, a thermochemical hydrogen production mechanism is configured, and the gas outlet pipe is connected in series with the heat source channels of the H2SO4 decomposer and the HI decomposer. Part of the heat energy of the furnace top gas is recovered for sulfur-iodine thermochemical hydrogen production, which meets the high-temperature requirements of sulfur-iodine thermochemical hydrogen production. This enables hydrogen recycling in the pure hydrogen vertical furnace, significantly reducing the production cost of the pure hydrogen vertical furnace and improving the reliability of pure hydrogen production. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of the hydrogen cycle system provided in an embodiment of the present invention;

[0021] Figure 2 A schematic diagram of the thermochemical hydrogen production mechanism provided in this embodiment of the utility model. Detailed Implementation

[0022] The technical solutions in the embodiments of this utility model are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0023] Example 1

[0024] like Figure 1 and Figure 2 This utility model provides a hydrogen circulation system for a pure hydrogen vertical furnace, including a heating furnace 5, a thermochemical hydrogen production mechanism 3, an outlet gas pipe 2 connected to the furnace top gas outlet of the vertical furnace 1, and a return gas pipe 4 connected to the reaction gas inlet of the vertical furnace 1.

[0025] In one embodiment, such as Figure 1 A dust collector 21 is provided on the gas outlet pipe 2 for dust removal of the furnace top gas. The dust collector 21 includes, but is not limited to, dust removal equipment such as cyclone dust collector 21.

[0026] In one embodiment, such as Figure 1 A dehydrator 22 is arranged on the gas outlet pipe 2 to dehydrate the gas at the top of the furnace. When a dust collector 21 is installed, preferably, the dehydrator 22 is arranged downstream of the dust collector 21, that is, the dust collector 21 and the dehydrator 22 are arranged sequentially along the gas flow direction at the top of the furnace.

[0027] In one embodiment, such as Figure 1 A furnace top gas compressor 23 is also arranged on the gas outlet pipe 2 to pressurize the gas in the pipe for subsequent processing. When a dehydrator 22 is installed, preferably, the furnace top gas compressor 23 is arranged downstream of the dehydrator 22.

[0028] In one embodiment, such as Figure 2 The thermochemical hydrogen production mechanism 3 includes a reactor 31, an H2SO4 decomposer 331, and an HI decomposer 341. The H2SO4 decomposer 331 is connected to the H2SO4 phase outlet of the reactor 31 through an H2SO4 medium pipe, and the HI decomposer 341 is connected to the HI phase outlet of the reactor 31 through an HI medium pipe.

[0029] The aforementioned reactor 31 is used to carry out the Bunsen reaction, and the reaction raw materials include SO2, H2O, and I2; optionally, such as Figure 2The thermochemical hydrogen production device 3 also includes a premixing tank 32. The mixing medium outlet of the premixing tank 32 is connected to the reaction medium inlet of the reactor 31. SO2, H2O and I2 are premixed in the premixing tank 32 in proportion, which can improve the Bunsen reaction effect.

[0030] In reactor 31, H2SO4 and HI phase solutions are generated. The H2SO4 phase solution has a lower density and tends to accumulate in the upper part of reactor 31, which can be drawn out through the H2SO4 medium pipe. The HI phase solution has a higher density and tends to accumulate in the lower part of reactor 31, which can be drawn out through the HI medium pipe.

[0031] Furthermore, such as Figure 2 An H2SO4 purification tower 332 and an H2SO4 concentration tower 333 are sequentially installed on the H2SO4 medium pipe. The H2SO4 phase solution purified by the H2SO4 purification tower 332 is concentrated by the H2SO4 concentration tower 333 and then enters the H2SO4 decomposer 331.

[0032] H2SO4 is endothermally decomposed into O2, SO2 and H2O in H2SO4 decomposer 331. Optionally, H2SO4 decomposer 331 is equipped with oxygen storage tank 334. The O2 obtained from the decomposition is led out to oxygen storage tank 334 for storage, while SO2 and H2O are preferably returned to premix tank 32 as reaction raw materials.

[0033] Furthermore, such as Figure 2 An HI purification tower 342 and an HI concentration device are sequentially installed on the HI medium pipe. The HI phase solution purified by the HI purification tower 342 is concentrated by the HI concentration device and then enters the HI decomposer 341. Preferably, the HI concentration device adopts an electrodialysis concentration device 343 and an HI distillation tower 344. In the electrodialysis concentration device 343, the I2 concentrate at the anode can be returned to the premix tank 32 as a reaction feedstock, while the HI phase concentrate at the cathode enters the HI distillation tower 344 for further distillation.

[0034] HI is endothermally decomposed into H2 and I2 in HI decomposer 341. Optionally, HI decomposer 341 is connected to hydrogen storage tank 345. The H2 obtained from the decomposition is led out to the hydrogen storage tank 345, while I2 is preferably returned to the premix tank 32 as a reaction raw material.

[0035] The hydrogen obtained from the decomposition in the HI decomposer 341 can be supplied to the vertical furnace 1 as a reaction gas. That is, the hydrogen storage tank 345 is connected to the reaction gas inlet of the vertical furnace 1 through the green hydrogen supply pipe 30.

[0036] In one embodiment, such as Figure 2The outlet pipe 2 is connected in series with the heat source channel of the H2SO4 decomposer 331 and the heat source channel of the HI decomposer 341, and then connected to the heat exchange gas inlet of the heating furnace 5. The return gas pipe 4 is connected to the heat exchange gas outlet of the heating furnace 5.

[0037] Among them, the heating furnace 5 is used to heat hydrogen, thereby improving the reaction efficiency and effect in the pure hydrogen vertical furnace 1.

[0038] Preferably, indirect heat exchange is used in the H2SO4 decomposer 331 and the HI decomposer 341, including but not limited to setting heat exchange tubes as heat source channels in the H2SO4 decomposer 331 and the HI decomposer 341 respectively. These heat exchange tubes are connected in series to the gas outlet pipe 2. In other words, the gas outlet pipe 2 includes two heat exchange tube sections extending into the H2SO4 decomposer 331 and the HI decomposer 341. Specifically, the gas outlet pipe 2 includes a first pipe section, a second pipe section, and a third pipe section. The inlet end of the first pipe section is connected to the furnace top gas outlet of the vertical furnace 1, and the outlet end of the first pipe section is connected to the inlet end of the heat exchange tube of the H2SO4 decomposer 331. The inlet end of the second pipe section is connected to the outlet end of the heat exchange tube of the H2SO4 decomposer 331, and the outlet end of the second pipe section is connected to the inlet end of the heat exchange tube of the HI decomposer 341. The inlet end of the third pipe section is connected to the outlet end of the heat exchange tube of the HI decomposer 341, and the outlet end of the third pipe section is connected to the heat exchange gas inlet of the heating furnace 5.

[0039] In this embodiment, a thermochemical hydrogen production mechanism 3 is configured, and the gas outlet pipe 2 is connected in series with the heat source channel of the H2SO4 decomposer 331 and the heat source channel of the HI decomposer 341. Part of the heat energy of the furnace top gas is recovered for sulfur-iodine thermochemical hydrogen production, which meets the high temperature requirements of sulfur-iodine thermochemical hydrogen production. This can realize the hydrogen circulation of the pure hydrogen shaft furnace 1, which can significantly reduce the production cost of the pure hydrogen shaft furnace 1 and improve the reliability of the pure hydrogen shaft furnace 1 production.

[0040] In one embodiment, when a dehydrator 22 is provided, the outlet of the dehydrator 22 is connected to the water inlet of the premix tank 32 to recover the water vapor removed from the furnace top gas as a raw material for hydrogen production, thereby reducing the water resources required for thermochemical hydrogen production and further improving the self-sufficiency of the hydrogen cycle.

[0041] When a dehydrator 22 is provided, the dehydrator 22 is located upstream of the heat source channel series connection area, which includes the heat exchange tubes of the H2SO4 decomposer 331, the second tube section, and the heat exchange tubes of the HI decomposer 341.

[0042] In one embodiment, the oxygen obtained from the decomposition in the H2SO4 decomposer 331 can be supplied to the heater 5 as fuel, further improving the self-sufficiency of the hydrogen cycle. Alternatively, the obtained oxygen can also be supplied to other oxygen-consuming units such as oxygen-enriched blast furnaces.

[0043] In one embodiment, the water produced by combustion in the heating furnace 5 can also be collected into the thermochemical hydrogen production unit 3 as raw material. Specifically, the heating furnace 5 is equipped with a water collection pipe, which is connected to the water inlet of the premixed tank 32 to reduce the water resources required for thermochemical hydrogen production and further improve the self-sufficiency of the hydrogen cycle.

[0044] The hydrogen supply in hydrogen storage tank 345 can be directly supplied to vertical furnace 1, or it can share a hydrogen channel with the furnace top gas. Optionally, such as... Figure 1 The outlet end of the green hydrogen supply pipe 30 is connected in parallel to the gas outlet pipe 2, so that the green hydrogen can be heated by the heating furnace 5 to ensure the smelting effect of the pure hydrogen shaft furnace 1. Further, as... Figure 1 The green hydrogen supply pipe 30 is also connected to a first bypass pipe 302, which is directly connected to the vertical furnace 1. Control valves are respectively provided on the green hydrogen supply pipe 30 and the first bypass pipe 302. The control valve on the green hydrogen supply pipe 30 is located downstream of the bypass point of the first bypass pipe 302. Based on this design, green hydrogen can be heated by the heating furnace 5 and then sent to the vertical furnace 1, or it can be directly supplied to the vertical furnace 1, or the two methods can be coupled together. Therefore, it is highly flexible. In particular, when two sets of reaction gas inlets are used on the vertical furnace 1, the effect of secondary reduction can be achieved, thereby improving the smelting effect of the vertical furnace 1. When the return gas pipe 4 is connected to the upper reaction gas inlet and the first bypass pipe 302 is connected to the lower reaction gas inlet, the directly supplied green hydrogen exchanges heat with the furnace charge. While pre-cooling the furnace charge, the heat of the furnace charge can also be fully utilized to heat this part of the directly supplied green hydrogen, ensuring its upward reaction effect and efficiency.

[0045] Optionally, a green hydrogen compressor 301 is provided on the green hydrogen supply pipe 30.

[0046] In one embodiment, such as Figure 1 A regenerator 24 is also arranged on the gas outlet pipe 2. The regenerator 24 is located downstream of the heat source channel connection area. The regenerator 24 can recover the heat of the furnace top gas and further improve the energy efficiency of the hydrogen cycle system.

[0047] In one embodiment, such as Figure 1 The gas outlet pipe 2 is also connected to a second bypass pipe 25. The outlet end of the second bypass pipe 25 is connected to the fuel gas inlet of the heating furnace 5, that is, a portion of the furnace top gas is used as the fuel gas for the heating furnace 5, which can further reduce the energy consumption of the hydrogen circulation system and thus reduce the production cost of the pure hydrogen vertical furnace 1. The inlet end of the second bypass pipe 25 is preferably located upstream of the heat source channel series connection area; when a regenerator 24 is provided, the second bypass pipe 25 is preferably connected in series with the regenerator 24 and the heating furnace 5.

[0048] In an optional embodiment, the top gas after heat exchange by the H2SO4 decomposer 331 and the HI decomposer 341 can also be used as fuel gas for the heating furnace 5, and the heat of these top gases can be further utilized. Accordingly, a third bypass pipe is also connected to the gas outlet pipe 2. The inlet end of the third bypass pipe is located downstream of the heat source channel series connection area, and the outlet end of the third bypass pipe is connected to the fuel gas inlet of the heating furnace 5.

[0049] In one embodiment, such as Figure 2 A fourth bypass pipe 26 is also connected to the gas outlet pipe 2. The two ends of the fourth bypass pipe 26 are located upstream and downstream of the heat source channel series connection area, respectively. A bypass valve is installed on the fourth bypass pipe 26. Based on this design, it is possible to control whether the furnace top gas passes through the H2SO4 decomposer 331 and the HI decomposer 341, or to control the flow rate of the furnace top gas passing through the H2SO4 decomposer 331 and the HI decomposer 341, further improving the production flexibility and reliability of the hydrogen cycle system.

[0050] By allocating the flow rates of the furnace top gas as reactant and fuel gas, as well as the flow rates of the furnace top gas passing through the H2SO4 decomposer 331 and HI decomposer 341, and the flow rates of hydrogen passing through the heating furnace 5 and the direct-supply vertical furnace 1, the production flexibility and reliability of the hydrogen circulation system and the pure hydrogen vertical furnace 1 can be greatly improved, and the energy efficiency control accuracy of the hydrogen circulation system can be greatly improved.

[0051] Example 2

[0052] This embodiment provides a pure hydrogen vertical furnace, which is equipped with the hydrogen circulation system of the pure hydrogen vertical furnace provided in Embodiment 1 above. The connection relationship between the gas outlet pipe 2, the gas return pipe 4 and the vertical furnace 1 has been described in Embodiment 1 above, and will not be repeated here.

[0053] Example 3

[0054] This embodiment provides a method for producing pure hydrogen using a vertical shaft furnace, which can be implemented based on the pure hydrogen vertical shaft furnace provided in Embodiment 2 above; the production method includes:

[0055] The gas from the top of vertical furnace 1 is drawn out.

[0056] At least a portion of the top gas is introduced into the thermochemical hydrogen production unit 3 as a heat source for H2SO4 decomposition and HI decomposition, and then the top gas drawn from the thermochemical hydrogen production unit 3 is sent to the vertical furnace 1 as a reaction gas and / or sent to the heating furnace 5 as a fuel gas.

[0057] The hydrogen produced by the thermochemical hydrogen production unit 3 is fed into the vertical furnace 1 as a reaction gas.

[0058] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A hydrogen circulation system for a pure hydrogen vertical shaft furnace, characterized in that, It includes a heating furnace, a thermochemical hydrogen production unit, an outlet gas pipe connected to the furnace top gas outlet of the vertical furnace, and a return gas pipe connected to the reaction gas inlet of the vertical furnace. The thermochemical hydrogen production apparatus includes a reactor, an H2SO4 decomposer, and an HI decomposer. The H2SO4 decomposer is connected to the H2SO4 phase outlet of the reactor via an H2SO4 medium pipe, and the HI decomposer is connected to the HI phase outlet of the reactor via an HI medium pipe. The outlet pipe is connected in series with the heat source channel of the H2SO4 decomposer and the heat source channel of the HI decomposer, and then connected to the heat exchange gas inlet of the heating furnace. The return gas pipe is connected to the heat exchange gas outlet of the heating furnace. The HI decomposer is connected to a hydrogen storage tank, which is connected to the reaction gas inlet of the vertical furnace via a green hydrogen supply pipe.

2. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 1, characterized in that: The outlet end of the green hydrogen supply pipe is connected to the gas outlet pipe.

3. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 2, characterized in that: A first bypass pipe is also connected to the green hydrogen supply pipe, which is directly connected to the vertical furnace. Control valves are respectively provided on the green hydrogen supply pipe and the first bypass pipe, and the control valve on the green hydrogen supply pipe is located downstream of the bypass point of the first bypass pipe.

4. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 1, characterized in that: A dehydrator is provided on the air outlet pipe, and the dehydrator is located upstream of the heat source channel connection area.

5. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 4, characterized in that: The thermochemical hydrogen production apparatus also includes a premixing tank, the mixing medium outlet of which is connected to the reaction medium inlet of the reactor, and the water outlet of the dehydrator is connected to the water supply port of the premixing tank.

6. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 1 or 5, characterized in that: The thermochemical hydrogen production apparatus also includes a premixing tank, the mixing medium outlet of which is connected to the reaction medium inlet of the reactor, and the heating furnace is equipped with a water collection pipe, which is connected to the water supply port of the premixing tank.

7. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 1, characterized in that: A regenerator is also installed on the gas outlet pipe, and the regenerator is located downstream of the heat source channel connection area.

8. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 7, characterized in that: A second bypass pipe is also connected to the gas outlet pipe, and the outlet end of the second bypass pipe is connected to the fuel gas inlet of the heating furnace.

9. The hydrogen circulation system of the pure hydrogen vertical furnace as described in claim 1, characterized in that: A third bypass pipe is also connected to the gas outlet pipe. The two ends of the third bypass pipe are located upstream and downstream of the heat source channel connection area, respectively, and a bypass valve is provided on the third bypass pipe.

10. A pure hydrogen vertical shaft furnace, characterized in that, A hydrogen circulation system is configured with a pure hydrogen vertical furnace as described in any one of claims 1 to 9.

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