Apparatus and process for producing reducing gas

Abstract

The application belongs to the technical field of direct reduction iron and discloses a device and process for producing reducing gas. The device for producing reducing gas comprises an oxidation conversion unit and a conditioning unit. The oxidation conversion unit is used for non-catalytic partial oxidation reforming of a hydrocarbon-containing raw material gas to produce high-temperature conversion gas. The conditioning unit is used for conditioning reaction of the high-temperature conversion gas to convert carbon dioxide and water vapor in the high-temperature conversion gas into carbon monoxide and hydrogen to produce product gas as reducing gas. The device and process for producing reducing gas solve the problem of catalyst poisoning and improve the quality of reducing gas.

Description

Technical Field

[0001] This invention relates to the field of direct reduced iron technology, specifically to an apparatus and process for producing reducing gas. Background Technology

[0002] Blast furnace ironmaking is the main source of CO2 emissions in the steel industry, accounting for over 70% of CO2 emissions. Against this backdrop, hydrogen-based vertical shaft furnace direct reduction ironmaking technology has become an important direction for the green transformation of the global steel industry due to its low-carbon emission advantages.

[0003] Currently, in regions with abundant natural gas resources abroad (such as the Middle East and North America), direct reduced iron production mainly uses natural gas as raw material, producing reducing gas through catalytic reforming. In countries like India and Iran, coal-based rotary kilns are the primary method, with reducing gas produced through coal-to-gas processes. In my country, the development of hydrogen-based vertical shaft furnaces is limited by natural resources; the main feedstock gas is coke oven gas, supplemented by natural gas and hydrogen, and catalytic reforming is commonly used to process the feedstock gas.

[0004] However, existing catalytic reforming processes have the following technical drawbacks: First, catalysts are susceptible to poisoning: catalysts are sensitive to impurities such as sulfur and chlorine in the feed gas. If purification is incomplete, catalyst deactivation can easily occur, affecting production continuity and efficiency. Second, feed gas adaptability is poor: when processing feed gas with high sulfur and high impurities, pretreatment costs are high and the process is complex. Third, energy utilization efficiency is low: the reforming process requires external heating, and there are many heat transfer links, resulting in low thermal efficiency. Fourth, product gas quality is limited: the reformed gas has a high CO2 and water vapor content, and the reducing gas concentration is low, affecting the reduction efficiency.

[0005] Therefore, developing a reducing gas production device and process that is highly adaptable to raw materials, has high conversion efficiency, good product quality, and high energy utilization efficiency has significant technological value and industrial significance. Summary of the Invention

[0006] In view of the above problems, the present invention proposes an apparatus and process for producing reducing gas that can solve the problem of catalyst poisoning and improve the quality of reducing gas.

[0007] The apparatus for producing reducing gas according to the present invention includes: an oxidation conversion unit and a conditioning unit. The oxidation conversion unit is used to perform non-catalytic partial oxidation reforming on hydrocarbon-containing feed gas to produce high-temperature converted gas. The conditioning unit is used to perform a conditioning reaction on the high-temperature converted gas to convert carbon dioxide and water vapor therein into carbon monoxide and hydrogen, and produce product gas as reducing gas.

[0008] Furthermore, the apparatus for producing reducing gas also includes a reduction unit and a circulating gas treatment unit. The inlet of the reduction unit is connected to the outlet of the conditioning unit and the outlet of the circulating gas treatment unit, respectively, and is used to receive the mixed reducing gas formed by the circulating coal gas from the circulating gas treatment unit and the product gas from the conditioning unit to reduce iron oxides and produce top coal gas. The inlet of the circulating gas treatment unit is connected to the top coal gas outlet of the reduction unit and is used to process the top coal gas and produce circulating coal gas.

[0009] Furthermore, the inlet of the conditioning unit is directly connected to the outlet of the oxidation conversion unit, and the conditioning unit is equipped with a heating device and carbon-based reactants.

[0010] Furthermore, the tempering unit is a group of one or more reaction units connected in series and parallel.

[0011] Furthermore, the recirculating gas treatment unit includes at least one of a pressurization unit, a heating unit, or a decarbonization unit.

[0012] Furthermore, the oxidation conversion unit is equipped with an auxiliary gas inlet for introducing carbon dioxide or water vapor to adjust the composition of the high-temperature conversion gas.

[0013] Furthermore, the mixing point of the circulating gas and the product gas is located before the inlet of the reduction unit, and there is no dehydration device in the mixing pipeline.

[0014] According to the process for producing reducing gas of the present invention, the apparatus for producing reducing gas includes the following steps: Step S1: Hydrocarbon-containing feed gas, oxygen and auxiliary gas are introduced into the oxidation conversion unit for non-catalytic partial oxidation reforming to produce high-temperature conversion gas; Step S2: The high-temperature conversion gas is directly introduced into the conditioning unit and reacted with carbon-based reactants under heating conditions to condition the gas and produce product gas as reducing gas.

[0015] Furthermore, the process for producing reducing gas also includes the following steps: Step S3: The top coal gas produced by the reduction unit is processed by the circulating gas treatment unit to obtain circulating coal gas; Step S4: The product gas is mixed with the circulating coal gas to form mixed reducing gas, which is then introduced into the reduction unit for direct reduction iron production.

[0016] Furthermore, in step S2, the temperature inside the conditioning unit is maintained at 1100-1150°C by a heating device, so that the carbon dioxide and water vapor in the high-temperature conversion gas undergo an endothermic reaction with the carbon-based reactants to generate carbon monoxide and hydrogen.

[0017] The apparatus and process for producing reducing gas of this invention first utilizes non-catalytic partial oxidation to rapidly crack hydrocarbons, providing highly reactive initial reformed gas containing certain oxidizing components. Then, leveraging the strong reducing properties of carbon-based reactants, CO2 and H2O are converted into CO and H2 through carbon dissolution reactions, achieving a significant improvement in the quality of the reducing gas. Finally, unreacted reducing components are recovered through top coal gas recycling, improving overall feedstock utilization. Simultaneously, the entire process maintains high-temperature operation, avoiding unnecessary cooling-heating stages and achieving efficient, cascaded energy utilization. Compared to traditional catalytic reforming processes, the apparatus and process for producing reducing gas of this invention have the following advantages: 1) The oxidation conversion furnace does not use a catalyst and is suitable for raw gas with high sulfur content. Non-catalytic oxidation is not sensitive to impurities such as sulfur, which completely solves the problem of catalyst poisoning. It can process inexpensive raw materials such as high-sulfur natural gas and coke oven gas, reducing pretreatment costs. 2) The oxidation conversion process is a direct combustion heating process, which has high thermal efficiency, low energy consumption, and high gas conversion efficiency; at the same time, it solves the problem of carbon precipitation of hydrocarbons, represented by CH4, during slow heating to a certain extent. 3) Along with the raw gas, CO2 gas or H2O vapor also enters the oxidation conversion furnace, which can realize CO2 recycling to a certain extent; 4) By using carbon-based conditioning, the CO2 and H2O that originally needed to be removed from the conversion gas are converted into CO and H2 in situ. The reducing potential of the product gas ((H2+CO) / (H2O+CO2)) is increased from about 4.2 to more than 200, which provides a fundamental guarantee for the efficient and low-consumption operation of the reduction furnace. 5) Oxidation conversion self-heating supply, the product gas and circulating gas are directly mixed at high temperature, eliminating the energy loss of cooling, dehydration and reheating in the traditional process; 6) The modulation unit can be heated by biomass carbon and green energy, with top coal gas recycling and partial CO2 recycling, resulting in a significantly lower overall carbon emission intensity than existing technologies. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the embodiments of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic diagram of an apparatus for producing reducing gas according to an embodiment of the present invention is shown. Detailed Implementation

[0019] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0020] Figure 1 The structure of an apparatus 100 for producing reducing gas according to an embodiment of the present invention is shown. Figure 1 As shown, the apparatus 100 for producing reducing gas may include: an oxidation conversion unit 1 and a conditioning unit 2. The oxidation conversion unit 1 is used to perform non-catalytic partial oxidation reforming on the hydrocarbon-containing feed gas to produce high-temperature conversion gas. The conditioning unit 2 is used to perform a conditioning reaction on the high-temperature conversion gas to convert the carbon dioxide and water vapor therein into carbon monoxide and hydrogen, and produce product gas as reducing gas.

[0021] In operation, the apparatus 100 for producing reducing gas according to this embodiment of the invention introduces hydrocarbon feedstock gas (such as natural gas), oxygen, and optional auxiliary gas (CO2 or water vapor) into the oxidation conversion unit 1. Inside the unit, non-catalytic partial oxidation reforming occurs, generating a high-temperature converted gas containing H2, CO, CO2, and H2O. This high-temperature converted gas is then directly introduced into the conditioning unit 2. The conditioning unit 2 reacts the CO2 and H2O in the high-temperature converted gas with carbon in an endothermic reaction (CO2 + C → 2CO, C + H2O → CO + H2), converting them into CO and H2, producing a high-quality product gas, i.e., reducing gas.

[0022] The reducing gas production apparatus 100 of this embodiment consists only of an oxidation conversion unit 1 and a conditioning unit 2, resulting in a simple structure. The oxidation conversion unit 1 employs non-catalytic partial oxidation reforming, eliminating the need for a catalyst and completely avoiding the catalyst poisoning problem in traditional catalytic reforming processes. It can handle high-sulfur, high-impurity hydrocarbon-containing feedstock gases (such as natural gas and coke oven gas), demonstrating strong feedstock adaptability. The conditioning unit 2 converts CO2 and H2O in the high-temperature reforming gas into CO and H2, significantly increasing the concentration of effective components (H2+CO) in the reducing gas and reducing the content of oxidizing components, thereby producing high-quality reducing gas. This apparatus provides a high-quality gas source for direct iron reduction, simplifies the pretreatment process, and reduces investment and operating costs.

[0023] According to the present invention, in such Figure 1In the preferred embodiment shown, the apparatus 100 for producing reducing gas may further include a reduction unit 3 and a circulating gas treatment unit 4. The inlet of the reduction unit 3 is connected to the outlet of the conditioning unit 2 and the outlet of the circulating gas treatment unit 4, respectively, for receiving the mixed reducing gas formed by the circulating coal gas from the circulating gas treatment unit 4 and the product gas from the conditioning unit 2, to reduce iron oxides and produce top coal gas. The inlet of the circulating gas treatment unit 4 is connected to the top coal gas outlet of the reduction unit 3, for processing the top coal gas and producing circulating coal gas. This embodiment integrates the reduction unit 3 and the circulating gas treatment unit 4, forming a complete closed loop for direct reduced iron (DRI) production. The reduction unit 3 uses the mixed reducing gas to produce DRI, and the circulating gas treatment unit 4 recovers unreacted reducing components (H2, CO) from the top coal gas and recycles them, significantly improving raw material utilization and energy efficiency. Simultaneously, the circulating coal gas is mixed with the product gas before entering the furnace, allowing for adjustment of the temperature, composition, and pressure of the reducing gas to meet different reduction process requirements.

[0024] In such Figure 1 In the preferred embodiment shown, the inlet of the conditioning unit 2 is directly connected to the outlet of the oxidation conversion unit 1. The conditioning unit 2 may be equipped with a heating device 21 and a carbon-based reactant 22. The direct connection between the inlet of the conditioning unit 2 and the outlet of the oxidation conversion unit 1 allows the high-temperature conversion gas at approximately 1150°C to directly enter the conditioning unit 2 without intermediate cooling, fully utilizing sensible heat for the endothermic carbon dissolution reaction, avoiding heat loss, and improving the system's thermal efficiency. The heating device 21 and the carbon-based reactant 22 within the conditioning unit 2 provide heat for the endothermic reaction, maintaining the optimal reaction temperature; the carbon-based reactant 22 provides the carbon source required for the reaction, converting CO2 and H2O in situ into CO and H2, which is the core means of improving the quality of the reducing gas.

[0025] In a preferred embodiment, the conditioning unit 2 can be one or more reaction groups connected in series and parallel, which can be flexibly configured according to the production scale. Series connection can increase the depth of single conversion, parallel connection can increase the throughput, and series-parallel combination can balance conversion rate and capacity, adapt to different operating conditions, and improve the system's operational flexibility and reliability.

[0026] In a preferred embodiment, the circulating gas treatment unit 4 may include at least one of a pressurization unit, a heating unit, or a decarbonization unit, which can be specifically adjusted according to the actual composition and state of the top coal gas, so that the temperature, pressure, and reduction potential of the circulating gas are directly satisfied by the product gas after mixing with it to meet the requirements of the reduction unit 3 for entering the furnace, avoiding additional heating or cooling and reducing energy consumption.

[0027] In a preferred embodiment, the oxidation conversion unit 1 may additionally be provided with an auxiliary gas inlet for introducing auxiliary gas (i.e., carbon dioxide or water vapor) to adjust the composition of the high-temperature conversion gas. This setting can, on the one hand, adjust the H2 / CO ratio of the high-temperature conversion gas to optimize the subsequent conditioning reaction; on the other hand, it can realize partial recycling of CO2, reduce carbon emissions, and meet the requirements of green and low-carbon development.

[0028] In another preferred embodiment, the auxiliary gas and the raw material gas can also be as follows: Figure 1 As shown, it enters the oxidation conversion unit 1 through an inlet.

[0029] According to the present invention, the carbon-based reactants can be biomass carbon or coal-based carbon materials. Biomass carbon is derived from renewable resources and can achieve carbon neutrality or even carbon negative emissions, thus contributing to carbon neutrality; coal-based carbon is inexpensive, has a stable source, and is economically viable, allowing for flexible selection based on environmental requirements and cost budgets.

[0030] Furthermore, the reduction unit 3 can preferably be a vertical reduction furnace, with a top gas outlet at the top and a reduced iron discharge outlet at the bottom. The vertical furnace structure facilitates countercurrent gas-solid contact, prolongs the reaction time between the gas and the iron ore, and improves the reduction efficiency; the top gas is naturally discharged from the top, making it easy to collect and process; the bottom discharge is continuous and stable, making it suitable for large-scale industrial production.

[0031] Furthermore, the mixing point of the circulating gas and the product gas is located before the inlet of reduction unit 3, and there is no dehydration device in the mixing pipeline. This setup makes full use of the sensible heat of the product gas (approximately 1100°C) and the circulating gas (which still has a relatively high temperature after treatment), directly mixing them before feeding them into the furnace. This avoids the energy waste of cooling and dehydrating before heating in traditional processes, significantly improving the system's thermal efficiency.

[0032] Furthermore, the feedstock gas can be natural gas, coke oven gas, or a mixture of both. In particular, it can make full use of coke oven gas, a byproduct of steel plants, turning waste into treasure, reducing the cost of purchasing natural gas, and improving the level of comprehensive resource utilization.

[0033] According to the embodiment of the present invention, the process for producing reducing gas using the above-mentioned apparatus 100 for producing reducing gas may include the following steps: Step S1: Hydrocarbon-containing raw material gas, oxygen and auxiliary gas are introduced into the oxidation conversion unit 1 for non-catalytic partial oxidation reforming to produce high-temperature conversion gas; Step S2: The high-temperature conversion gas is directly introduced into the conditioning unit 2 and reacted with carbon-based reactants under heating conditions to condition the gas and produce product gas as reducing gas.

[0034] Furthermore, the process for producing reducing gas in this embodiment of the invention may further include step S3: processing the top coal gas produced by the reduction unit 3 through the circulating gas treatment unit 4 to obtain circulating coal gas; step S4: mixing the product gas with the circulating gas to form mixed reducing gas, which is then introduced into the reduction unit 3 for direct reduction iron production.

[0035] The process for producing reducing gas is simple, with each unit closely integrated, enabling continuous production from raw materials to finished products. Through three core operations—non-catalytic oxidation reforming, carbon-based conditioning, and top gas recirculation—traditional problems such as catalyst poisoning and carbon precipitation are avoided. At the same time, the high-temperature product gas and recirculated gas are directly mixed into the furnace, reducing intermediate cooling-heating-dehydration steps, resulting in low overall energy consumption, high-quality reducing gas, and low carbon emissions.

[0036] Preferably, in step S2, the temperature within the conditioning unit 2 is maintained at 1100-1150℃ by the heating device 21, causing the carbon dioxide and water vapor in the high-temperature conversion gas to undergo an endothermic reaction with the carbon-based reactants, generating carbon monoxide and hydrogen. Within this temperature window, the carbon dissolution reactions (C+CO2→2CO, C+H2O→CO+H2) exhibit extremely high reaction rates and equilibrium constants, with CO2 and H2O conversion rates reaching over 95%. The reduction quality of the product gas ((H2+CO) / (H2O+CO2)) can be increased from approximately 4.2 before conditioning to over 200, while effectively avoiding the problems of low-temperature carbon precipitation and excessive high-temperature energy consumption, which is crucial for ensuring efficient process operation.

[0037] In summary, the apparatus 100 for producing reducing gas in this embodiment integrates the oxidation conversion unit 1, conditioning unit 2, reduction unit 3, and recycle gas treatment unit 4 into a closed-loop system. The oxidation conversion unit 1 employs non-catalytic partial oxidation, completely avoiding catalyst poisoning and offering broad raw material adaptability. The conditioning unit 2 utilizes carbon-based reactants to efficiently convert CO2 and H2O in the conversion gas into CO and H2, significantly improving the quality of the reducing gas. The reduction unit 3 directly utilizes the mixed reducing gas to produce direct reduced iron. The recycle gas treatment unit 4 recovers and recycles the effective components in the top coal gas, significantly improving energy efficiency and resource utilization. The four units are organically coupled, realizing efficient and low-carbon production from raw gas to high-quality reduced iron throughout the entire process.

[0038] The following are specific embodiments of the apparatus and process for producing reducing gas using the present invention.

[0039] The apparatus for producing reducing gas in this embodiment consists of two parts: Oxidation conversion unit 1, a non-catalytic partial oxidation conversion furnace with a design temperature of 1200℃ and lined with refractory material; Modulation unit 2, a vertical reactor filled with carbon-based reactants (using biomass carbon with a particle size of 10-30mm) and equipped with an external electric heating device; Reduction unit 3, a vertical reduction furnace with an effective height of 25m, a top gas outlet at the top, and a reduced iron outlet at the bottom; and Circulating gas treatment unit 4, which includes a pressurization unit (centrifugal compressor) and a decarbonization unit (using MDEA chemical absorption method to remove CO2).

[0040] Natural gas is used as the feedstock, and its composition is shown in Table 1 below: Table 1

[0041] The natural gas, along with O2 at a specific ratio, temperature, and purity, and H2O vapor at a specific temperature and ratio, is fed into oxidation reformer 1 for reforming. The resulting high-temperature reformed gas has a temperature of approximately 1150°C. Approximately 3 volumes of reformed gas are generated from 1 volume of natural gas, and their compositions are shown in Table 2 below. Table 2

[0042] The reformed gas is introduced into conditioning unit 2, and the system temperature is maintained at ~1130℃ by a heating device. CO2, H2O, etc. in the reformed gas will undergo a reforming reaction with C in the carbon-filled device. The theoretical composition of the product gas after conditioning is shown in Table 3 below: Table 3

[0043] The data in the table shows that the mass of the reformed gas is: reducing gas mass = reducing agent / oxidizing agent = (H2% + CO%) / (H2O% + CO2%) ≈ 4.2. The mass of the reducing gas obtained after conditioning is: (H2% + CO%) / (H2O% + CO2%) ≈ 211. The mass of the reducing gas has increased by approximately 50 times, demonstrating a significant improvement in gas quality. Similarly, the mass of the reducing gas entering the reduction furnace has also been significantly improved, laying the foundation for the high efficiency and low consumption of the reduction furnace.

[0044] In the vertical reduction furnace, mixed reducing gas is countercurrently contacted with iron ore for reduction, and the resulting top gas is discharged from the top gas outlet. The main components of the top gas are: approximately 35% H2, approximately 25% CO, approximately 20% CO2, approximately 15% H2O, and approximately 5% N2, with a temperature of approximately 350℃. This top gas enters the circulating gas treatment unit 4, where it is first pressurized to 0.4 MPa by a pressurization unit, and then enters the decarbonization unit where CO2 is removed by MDEA solution absorption, reducing the CO2 content in the outlet gas to approximately 3%. The resulting circulating gas has the following composition: approximately 48% H2, 34% CO, 10% H2O, 3% CO2, and 5% N2, with a temperature of approximately 60℃.

[0045] The 1150℃ product gas from the quenching and tempering unit 2 and the 60℃ circulating gas from the circulating gas treatment unit are directly mixed at the mixing point to form a mixed reducing gas. The temperature of the mixed gas is approximately 850℃, and the mass of the reducing gas ((H2+CO) / (H2O+CO2)) is approximately 8.75, which meets the requirements of the vertical shaft furnace direct reduction process. This mixed reducing gas enters the vertical shaft furnace from the lower inlet of the reduction unit and comes into countercurrent contact with the iron ore added at the top of the furnace, where a reduction reaction occurs. The reduced product, direct reduced iron, is continuously discharged from the reduced iron outlet at the bottom of the furnace, with a metallization rate of over 92%.

[0046] In summary, this embodiment verifies the effectiveness of the apparatus and process of the present invention. By combining non-catalytic partial oxidation reforming with carbon-based conditioning, natural gas was successfully converted into high-quality reducing gas, with the quality of the reducing gas improved by approximately 50 times. The recycling of top coal gas further reduces raw material consumption, and high-temperature mixing eliminates the intermediate cooling, dehydration, and reheating steps, significantly improving energy utilization efficiency. The entire process does not use any catalyst and has no special requirements for the sulfur content of the raw gas, demonstrating strong industrial applicability and economic viability.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An apparatus for producing reducing gas, characterized in that, include: The unit comprises an oxidation conversion unit and a conditioning unit. The oxidation conversion unit is used to perform non-catalytic partial oxidation reforming on hydrocarbon-containing feed gas to produce high-temperature converted gas. The conditioning unit is used to perform a conditioning reaction on the high-temperature converted gas to convert carbon dioxide and water vapor into carbon monoxide and hydrogen, and produce product gas as a reducing gas.

2. The apparatus for producing reducing gas according to claim 1, characterized in that, The apparatus for producing reducing gas further includes a reduction unit and a circulating gas treatment unit. The inlet of the reduction unit is connected to the outlet of the conditioning unit and the outlet of the circulating gas treatment unit, respectively, for receiving a mixed reducing gas formed by circulating coal gas from the circulating gas treatment unit and product gas from the conditioning unit, in order to reduce iron oxides and produce top coal gas. The inlet of the circulating gas treatment unit is connected to the top gas outlet of the reduction unit, and is used to treat the top gas and produce the circulating gas.

3. The apparatus for producing reducing gas according to claim 1 or 2, characterized in that, The inlet of the conditioning unit is directly connected to the outlet of the oxidation conversion unit, and the conditioning unit is equipped with a heating device and carbon-based reactants.

4. The apparatus for producing reducing gas according to claim 1 or 2, characterized in that, The conditioning unit is one or more reaction groups connected in series and parallel.

5. The apparatus for producing reducing gas according to claim 2, characterized in that, The circulating gas treatment unit includes at least one of a pressurization unit, a heating unit, or a decarbonization unit.

6. The apparatus for producing reducing gas according to claim 1 or 2, characterized in that, The oxidation conversion unit is provided with an auxiliary gas inlet for introducing carbon dioxide or water vapor to adjust the composition of the high-temperature conversion gas.

7. The apparatus for producing reducing gas according to claim 2, characterized in that, The mixing point of the circulating gas and the product gas is located before the inlet of the reduction unit, and no dehydration device is provided in the mixing pipeline.

8. A process for producing reducing gas, using the apparatus for producing reducing gas according to any one of claims 1 to 7, comprising the following steps: Step S1: Hydrocarbon-containing feed gas, oxygen, and auxiliary gas are introduced into the oxidation conversion unit for non-catalytic partial oxidation reforming to produce high-temperature reformed gas; Step S2: The high-temperature conversion gas is directly introduced into the conditioning unit, where it reacts with carbon-based reactants under heating conditions to condition the gas, and the resulting product gas is used as a reducing gas.

9. The process for producing reducing gas according to claim 8, characterized in that, It also includes the following steps: Step S3: The top coal gas produced by the reduction unit is processed by the circulating gas treatment unit to obtain circulating coal gas; Step S4: Mix the product gas with the circulating coal gas to form a mixed reducing gas, which is then introduced into the reduction unit for direct reduction iron production.

10. The process for producing reducing gas according to claim 8 or 9, characterized in that, In step S2, the temperature inside the conditioning unit is maintained at 1100-1150°C by the heating device, so that the carbon dioxide and water vapor in the high-temperature conversion gas undergo an endothermic reaction with the carbon-based reactants to generate carbon monoxide and hydrogen.

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