Continuous flow battery-grade ferrous liquid byproduct hydrogen recovery system

Abstract

The utility model relates to the technical field of iron source ferrous liquid preparation, in particular to a continuous flow battery grade ferrous liquid byproduct hydrogen recovery system which comprises a tubular reactor, a gas-liquid separation unit, a drying unit, a purification unit, a hydrogen buffer tank and a gas-fired boiler unit which are sequentially connected, the byproduct hydrogen-containing acid mist of the tubular reactor is subjected to gas-liquid separation through the gas-liquid separation unit, the separated acid liquid flows back to the tubular reactor, and the hydrogen-containing gas is subjected to moisture removal through the drying unit; the purification unit comprises a chemical deaerator and an adsorption deaerator which are connected in series, the hydrogen-containing gas is subjected to oxygen removal through the purification unit, the dried and purified hydrogen-containing gas is conveyed to a hydrogen buffer tank to detect the oxygen content, and the hydrogen-containing gas is used as fuel gas of the gas-fired boiler unit to be combusted after being detected to be qualified. By means of the efficient integrated tubular reactor, the gas-liquid separation unit, the drying unit, the purification unit and the gas-fired boiler unit, efficient recovery and utilization of the byproduct hydrogen are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of the preparation of ferrous liquid as iron source, and specifically, to a system for recovering by-product hydrogen from continuous-flow battery-grade ferrous liquid. Background Art

[0002] With the vigorous development of the new energy vehicle industry and the continuous growth of the demand for energy storage systems globally, as a core component among them, the demand for lithium iron phosphate batteries shows a sharp upward trend. Ferric phosphate, as the key precursor of the lithium iron phosphate cathode material, its quality and cost directly affect the performance and economy of lithium iron phosphate batteries. In order to meet the urgent market demand for high-quality ferric phosphate, the iron process for continuous full-process preparation has gradually become a research hotspot and application focus in the industry due to its advantages such as high efficiency, high degree of automation, stable product quality, and low environmental pollution.

[0003] During the preparation of continuous-flow battery-grade ferrous liquid, a large amount of hydrogen is generated. However, currently, these hydrogen gases are usually directly discharged into the atmosphere, which not only causes a waste of a large amount of high-purity hydrogen resources, but also the external discharge of hydrogen poses potential safety hazards. With the expansion of the production scale of battery-grade ferrous liquid, the amount of hydrogen discharged externally also increases correspondingly, which poses a severe challenge to environmental safety and resource utilization. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a system for recovering by-product hydrogen from continuous-flow battery-grade ferrous liquid to solve the problems raised in the above background art that currently these hydrogen gases are usually directly discharged into the atmosphere, which not only causes a waste of a large amount of high-purity hydrogen resources, but also the external discharge of hydrogen poses potential safety hazards.

[0005] To achieve the above purpose, the utility model provides a system for recovering by-product hydrogen from continuous-flow battery-grade ferrous liquid, which is characterized in that it includes a tubular reactor, a gas-liquid separation unit, a drying unit, a purification unit, a hydrogen buffer tank, and a gas-fired boiler unit connected in sequence. The gas-liquid separation unit includes a wire mesh separator and a heat exchanger connected in series. The by-product hydrogen-containing acid mist from the tubular reactor undergoes gas-liquid separation through the gas-liquid separation unit, and the separated acid liquid flows back to the tubular reactor. The hydrogen-containing gas removes moisture through the drying unit. The purification unit includes a chemical deoxidizer and an adsorption deoxidizer connected in series. The hydrogen-containing gas removes oxygen through the purification unit. The dried and purified hydrogen-containing gas is transported to the hydrogen buffer tank for oxygen content detection. After passing the detection, it is used as fuel gas for the gas-fired boiler unit for combustion, and the combustion heat is used for the tubular reactor or the chemical heating unit.

[0006] Preferably, the wire mesh separator is a stainless steel wire mesh separator, which is composed of a wire mesh block and a support frame. An air inlet is arranged at the bottom of the side wall of the support frame, an exhaust port is arranged at the top, and a liquid drain port is arranged at the bottom. The exhaust port is connected to the air inlet of the heat exchanger, and the liquid drain port is connected to the feed port of the tubular reactor; the wire mesh block is composed of multiple layers of wire mesh and wire mesh grids, and the wire mesh is preferably made of stainless steel wire. The hydrogen-containing acid mist is initially separated from the liquid droplets and the hydrogen-containing gas by the wire mesh separator. The separated liquid droplets are collected at the bottom of the support frame and recycled to the tubular reactor to continue participating in the reaction.

[0007] Preferably, the heat exchanger is a graphite heat exchanger, which uses condensed water to exchange heat with the hydrogen-containing acid mist. The liquid drain port at the bottom of the heat exchanger is connected to the feed port of the tubular reactor. The acid mist after preliminary separation is about 70°C and enters the heat exchanger to exchange heat with the condensed water at about 25°C in the heat exchanger, so that further liquefaction obtains liquid droplets, which are recycled to the tubular reactor to continue participating in the reaction.

[0008] Preferably, the drying unit is composed of multiple adsorption-type hydrogen dryers, and activated alumina is used as an adsorbent to adsorb the moisture in the hydrogen-containing gas.

[0009] Preferably, the chemical reagents in the chemical deoxidizer are hydrazine and sodium sulfite, and the adsorbents in the adsorption deoxidizer are activated carbon or molecular sieves. The oxygen in the hydrogen-containing gas is removed by different deoxidation methods.

[0010] Preferably, the hydrogen buffer tank is connected to the gas-fired boiler unit through a Roots blower, and oxygen is transported through the Roots blower to achieve stable flow and pressure control.

[0011] Preferably, the hydrogen buffer tank is connected to the drying unit through a blower. The gas with unqualified oxygen content or insufficient dryness returns to the drying unit and the purification unit through the blower, and the hydrogen-containing gas is further dried and deoxidized to meet the combustible index.

[0012] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0013] In this continuous flow battery-grade ferrous liquid by-product hydrogen recovery system, through the efficient integration of a tubular reactor, a gas-liquid separation unit, a drying unit, a purification unit and a gas-fired boiler unit, the efficient recovery and utilization of by-product hydrogen are realized. This system not only significantly reduces the waste of resources caused by direct hydrogen emission, but also effectively eliminates the safety hazards brought by hydrogen leakage, and greatly improves the environmental friendliness and safety of the production process.

[0014] Specifically, the system effectively separates acid mist and hydrogen through a gas-liquid separation unit, enabling the acid liquid to flow back for reuse and reducing raw material consumption. The drying unit adopts an adsorption technology and uses activated alumina to efficiently remove moisture in hydrogen, ensuring the dryness of hydrogen. The purification unit ensures the purity of hydrogen through a dual mechanism of chemical deoxidation and adsorption deoxidation, guaranteeing the safety of subsequent transportation and use. In addition, the setting of the hydrogen buffer tank and the Roots blower transportation method for the gas boiler unit ensure the stability of hydrogen flow and the accuracy of pressure control, further enhancing the overall performance of the system.

[0015] Ultimately, the system not only reduces the production cost for the preparation of electronic-grade ferrous liquid, enhances the market competitiveness of the product, but also reduces the heat source cost of the heat exchange system by recycling high-quality hydrogen, achieving the recycling of resources. The recycled hydrogen can be used for gas boilers or the synthesis of other downstream products according to actual needs, providing strong support for the enterprise's energy conservation, emission reduction and sustainable development. Brief Description of the Drawings

[0016] Figure 1 is a schematic diagram of the overall structure of the present utility model;

[0017] Figure 2 is a schematic diagram of the structure of the wire mesh separator in the present utility model;

[0018] Figure 3 is a schematic diagram of the structure of the wire mesh block in the present utility model;

[0019] The meanings of each reference numeral in the figure are as follows:

[0020] 1, tubular reactor; 2, gas-liquid separation unit; 21, wire mesh separator; 211, wire mesh block; 2111, wire mesh; 2112, wire mesh grid; 212, support frame; 22, heat exchanger; 3, drying unit; 4, purification unit; 41, chemical deoxidizer; 42, adsorption deoxidizer; 5, buffer tank; 6, gas boiler unit; 7, external chemical heating unit; 8, Roots blower. Detailed Embodiments

[0021] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0022] The present utility model provides a continuous flow battery-grade ferrous liquid by-product hydrogen recovery system, as Figures 1 - 3As shown in the figure, it includes a tubular reactor 1, a gas-liquid separation unit 2, a drying unit 3, a purification unit 4, and a gas-fired boiler unit 6. The by-product hydrogen and acid mist from the tubular reactor 1 pass through the gas-liquid separation unit 2. The acid liquid separated by the gas-liquid separation unit 2 flows back to the tubular reactor 1 for continuous iron production, and the gas removes moisture and residual moisture through the drying unit 3. Oxygen is separated through the purification unit 4 to ensure the safety of hydrogen pipeline transportation. The dried and purified hydrogen is transported to the hydrogen buffer tank 5 for oxygen content detection. After passing the detection, the hydrogen is used as fuel gas for the gas-fired boiler unit 6 to burn to compensate for the heat required by the tube reactor heat exchange system and the external chemical heating unit 7. Through delicate design, the tubular reactor 1, the gas-liquid separation unit 2, the drying unit 3, the purification unit 4, and the gas-fired boiler unit 6 are organically integrated, realizing the efficient, safe recovery and reuse of by-product hydrogen. This system not only effectively solves the problems of resource waste and safety hazards caused by direct hydrogen emission in traditional processes, but also significantly improves the environmental protection and economy of the production process.

[0023] Specifically, the by-product hydrogen and acid mist generated by the tubular reactor 1 first enter the gas-liquid separation unit 2. Through efficient separation technology, the acid liquid is accurately refluxed to the tubular reactor 1 for continuous iron production for reuse, thus reducing raw material waste and environmental pollution. The separated gas then enters the drying unit 3, and moisture and residues are completely removed through advanced drying technology to ensure the dry purity of hydrogen. Subsequently, the gas enters the purification unit 4, and oxygen is effectively separated through a precise purification process to further ensure the safety of hydrogen pipeline transportation.

[0024] The hydrogen after drying and purification is transported to the hydrogen buffer tank 5 for oxygen content detection to ensure that the hydrogen quality meets high-standard requirements. After passing the detection, the hydrogen is sent into the gas-fired boiler unit 6 as high-quality fuel gas for combustion, which not only provides the necessary heat compensation for the tube reactor heat exchange system, but also meets the energy requirements of the external chemical heating unit 7, realizing the efficient recycling of energy.

[0025] In summary, the by-product hydrogen recovery system for continuous-flow battery-grade ferrous liquid of the present utility model not only reduces production costs and enhances the market competitiveness of products by efficiently recovering and reusing by-product hydrogen, but also significantly enhances the environmental protection and safety of the production process, laying a solid foundation for the sustainable development of the enterprise.

[0026] In this embodiment, a wire mesh separator 21 and a heat exchanger 22 are installed inside the gas-liquid separation unit 2 for the acid mist and hydrogen to pass through in sequence. This greatly reduces the corrosion of the drying equipment in the subsequent process by the acid mist and extends the replacement cycle of the desiccant.

[0027] Specifically, a chemical deoxidizer 41 and an adsorption deoxidizer 42 are installed inside the purification unit 4.

[0028] Furthermore, the tubular reactor 1 can continuously and stably output hydrogen, and its exhaust port is connected to the gas-liquid separation unit 2.

[0029] Furthermore, the wire mesh separator 21 is a stainless-steel wire mesh separator, which is composed of a wire mesh block 211 and a support frame 212. The wire mesh block is composed of multiple layers of wire meshes 2111 and wire mesh grids 2112. The wire mesh is preferably made of stainless-steel wire. The heat exchanger 22 can be a graphite heat exchanger, and condensed water is used as the cooling water. When the hydrogen-containing gas just comes out, it is about 70 °C. After heat exchange, it enters the heat exchanger 22 at 30 °C - 35 °C, and the temperature of the condensed water in the heat exchanger 22 is 25 - 28 °C. The bottom of the wire mesh separator 21 and the bottom drain port of the heat exchanger 22 return to the feed port of the tubular reactor 1.

[0030] Furthermore, the drying unit 3 is an adsorption-type hydrogen dryer, and activated alumina is used as the adsorbent to adsorb water molecules in hydrogen.

[0031] Furthermore, the chemical reagents in the chemical deoxidizer 41 are hydrazine and sodium sulfite, and the adsorbents in the adsorption deoxidizer 42 are activated carbon or molecular sieve. A hydrogen buffer tank 5 is arranged between the purification unit 4 and the gas-fired boiler unit 6. The hydrogen buffer tank 5 and the gas-fired boiler unit 6 are transported by a Roots blower 8 to achieve stable flow and pressure control. An oxygen content detector is installed on the buffer tank 5 to ensure the safety of the hydrogen buffer tank and the hydrogen pipeline system; there is a two-way communication pipeline between the buffer tank 5 and the drying unit to ensure that the hydrogen in the buffer tank meets the drying standard.

[0032] Furthermore, the hydrogen buffer tank 5 is connected to the drying unit 3, and hydrogen is pumped into the hydrogen buffer tank 5 after drying cycle.

[0033] When the continuous-flow battery-grade ferrous liquid by-product hydrogen recovery system of the present utility model is in use, first in the tubular reactor 1, hydrogen with acid mist is generated during the preparation process of battery-grade ferrous liquid.

[0034] The hydrogen with acid mist first enters the gas-liquid separation unit 2. In the gas-liquid separation unit 2, the hydrogen passes through the wire mesh separator 21 and the heat exchanger 22, and most of the acid mist is condensed and separated. The separated acid liquid flows back to the tubular reactor 1 for reuse, reducing raw material waste and environmental pollution.

[0035] The separated gas enters the drying unit 3. In the drying unit 3, the gas passes through the adsorption-type hydrogen dryer, and activated alumina is used as the adsorbent to completely remove moisture and residues to ensure the dry purity of hydrogen.

[0036] The dried gas enters the purification unit 4. In the purification unit 4, the gas first passes through a chemical deoxidizer 41, where chemical reagents such as hydrazine and sodium sulfite are used to remove oxygen. Then it passes through an adsorption deoxidizer 42, where adsorbents such as activated carbon or molecular sieves are used to further remove the residual oxygen, ensuring the purity of hydrogen and the safety of pipeline transmission.

[0037] The purified hydrogen is transported to the hydrogen buffer tank 5 for oxygen content detection. The buffer tank 5 has a two-way communication pipeline with the drying unit 3 to ensure the dryness of the hydrogen in the buffer tank. The buffer tank is equipped with an oxygen detector to ensure that the oxygen content is lower than the specified standard (such as 0.5%).

[0038] The hydrogen after passing the detection is sent into the gas boiler unit 6 as high-quality fuel gas for combustion. The heat generated by combustion is used to compensate for the heat required by the tubular reactor 1 or the energy demand of the external chemical heating unit 7, and the chemical heating unit 7 can be other boilers or reaction equipment.

[0039] The above shows and describes the basic principles, main features and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only the preferred examples of the present utility model and are not used to limit the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A continuous flow hydrogen recovery system for by - product hydrogen from battery - grade ferrous solution, characterized in that: It includes a tubular reactor (1), a gas-liquid separation unit (2), a drying unit (3), a purification unit (4), a hydrogen buffer tank (5), and a gas-fired boiler unit (6) connected in sequence. The gas-liquid separation unit (2) includes a wire mesh separator (21) and a heat exchanger (22) connected in series. The by-product hydrogen-containing acid mist from the tubular reactor (1) undergoes gas-liquid separation in the gas-liquid separation unit (2). The separated acid liquid is refluxed to the tubular reactor (1), and the hydrogen-containing gas removes moisture through the drying unit (3). The purification unit (4) includes a chemical deoxidizer (41) and an adsorption deoxidizer (42) connected in series. The hydrogen-containing gas removes oxygen through the purification unit (4). The dried and purified hydrogen-containing gas is transported to the hydrogen buffer tank (5) for oxygen content detection. After passing the detection, it is used as fuel gas for the gas-fired boiler unit (6) for combustion, and the combustion heat is used for the tubular reactor (1) or the chemical heating unit (7).

2. The continuous flow battery-grade ferrous liquid by-product hydrogen recovery system according to claim 1, wherein: The wire mesh separator (21) is a stainless steel wire mesh separator, which is composed of a wire mesh block (211) and a support frame (212). The bottom of the side wall of the support frame (212) is provided with an air inlet, the top is provided with an exhaust port, and the bottom is provided with a liquid discharge port. The exhaust port is connected to the air inlet of the heat exchanger (22), and the liquid discharge port is connected to the feed port of the tubular reactor (1). The wire mesh block (211) is composed of multiple layers of wire meshes (2111) and wire mesh grids (2112). The wire mesh is preferably made of stainless steel wire.

3. The continuous flow battery-grade ferrous solution by-product hydrogen recovery system according to claim 1, wherein: The heat exchanger (22) is a graphite heat exchanger, which uses condensed water to exchange heat with the hydrogen-containing acid mist. The bottom liquid discharge port of the heat exchanger (22) is connected to the feed port of the tubular reactor (1).

4. The continuous flow battery-grade ferrous liquid by-product hydrogen recovery system according to claim 1, characterized in that: The drying unit (3) is composed of multiple adsorption-type hydrogen dryers.

5. The continuous flow battery-grade ferrous liquid by-product hydrogen recovery system according to claim 1, characterized in that: In the adsorption deoxidizer (42), it is an activated carbon or molecular sieve adsorption deoxidizer.

6. The continuous flow battery-grade ferrous liquid by-product hydrogen recovery system according to claim 1, characterized in that: The hydrogen buffer tank (5) is connected to the gas-fired boiler unit (6) through a Roots blower (8).

7. The continuous flow battery-grade ferrous liquid by-product hydrogen recovery system according to claim 1, characterized in that: The hydrogen buffer tank (5) is connected to the drying unit (3) through a blower to further dry and deoxidize the hydrogen-containing gas.

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