Gas-based vertical shaft furnace direct reduction method

Abstract

This invention discloses a direct reduction method for a gas-based vertical shaft furnace, belonging to the field of non-blast furnace ironmaking. The method involves adding iron oxides from the top of the furnace. The furnace's self-produced purified coal gas and raw material gas II are heated by heating devices one and two, respectively, and then injected into the furnace from the reduction section. Raw material gas I is injected into the furnace from the lower part of the cooling section. Inside the furnace, raw material gas I, raw material gas II, and the furnace's self-produced purified coal gas react with the iron oxides. The resulting gas enters a coal gas purification device, reducing the iron oxides to direct reduced iron (DRF). The DPF is then discharged from the furnace through the cooling section. Heating device two includes at least two independent heating furnaces. Carbon deposits are cleaned by introducing high-temperature steam and / or air into these independent heating furnaces. The heating devices employ regenerative combustion technology. This invention solves the problems of high investment and operating costs associated with gas-based vertical shaft furnaces, as well as the problem of carbon buildup during heating of coke oven gas and coal-to-gas processes, which affects normal production operations. It offers advantages over existing processes.

Description

Technical Field

[0001] This invention belongs to the field of non-blast furnace ironmaking, specifically relating to a direct reduction method for a gas-based vertical shaft furnace. Background Technology

[0002] The gas-based vertical shaft furnace direct reduction process is a non-blast furnace ironmaking process and the world's largest producer of direct reduced iron (DRI). DRI, as a high-quality raw material used in electric arc furnaces, converters, blast furnaces, and powder metallurgy, has received increasing attention from the government and the metallurgical industry in recent years. As a raw material for electric arc furnace steelmaking, DRI can improve the purity of molten steel and is a high-quality raw material required for special steel smelting. Especially for electric arc furnace enterprises with unstable scrap steel quality, adding DRI can dilute harmful elements in the steel and stabilize the quality of the molten steel. DRI does not use coke, and iron ore does not need sintering, saving coking coal resources and reducing the two stages with the largest emissions of waste gas in steel enterprises: coking and sintering, making it more environmentally friendly than the blast furnace process. In this article, any one of the following gases—purified coal gas produced by the vertical shaft furnace, raw material gas one, raw material gas two, coke oven gas, coal-to-gas, and natural gas—is collectively referred to as reducing gas.

[0003] There are two existing methods for direct reduction (DR) processes using gas-based vertical shaft furnaces: One method involves purifying a portion of the furnace's self-produced crude gas into purified gas, then mixing the natural gas and purified gas and heating the mixture to create hot reformed gas, which is then injected into the furnace from the reduction section. The other method involves purifying a portion of the furnace's self-produced crude gas into purified gas, then heating the mixture of natural gas and purified gas, followed by oxygen enrichment and temperature enhancement before injecting the hot mixture into the furnace from the reduction section. The reducing gas injected into the furnace directly contacts the iron oxide material, operating in a counter-current manner. The material moves downwards due to gravity, while the high-temperature reducing gas moves upwards. During this process, the reducing gas reduces the iron oxides to direct reduced iron (DRF). The disadvantages of existing gas-based vertical shaft furnaces are: 1. High investment: The MIDREX, HYLIII, and PERED processes in gas-based vertical shaft furnaces all require a feedstock gas reforming process. Although ENERGIRON-ZR does not require a catalytic reforming process, it adds an oxygen production process and an oxygen-enriched heating process, all of which involve high investment. 2. High operating costs: The catalyst, oxygen production, electricity, and labor costs in the reforming, oxygen production, and oxygen-enriched heating processes result in excessively high production costs. 3. Carbon buildup during feedstock gas heating affects normal production operations: The existing MIDREX, PERED, and HYL processes in gas-based vertical shaft furnaces all use natural gas as feedstock. However, China's current fuel resources are characterized by a shortage of natural gas and an abundance of coal. The most usable gas sources are coke oven gas and coal-to-gas. If coke oven gas is used... 1. The technology using coal gas as raw material still applies the process of gas-based vertical shaft furnaces using natural gas as the gas source. This makes coke oven gas and coal gas more prone to carbon buildup during heating, affecting normal production and potentially causing serious accidents. 2. The product is high-temperature hot-pressed iron blocks, resulting in heat loss in the vertical shaft furnace and increased water consumption: High-temperature direct reduced iron is hot-pressed into iron blocks at 700 degrees Celsius and then cooled with water, wasting a large amount of reduced iron heat energy, increasing water consumption, and causing significant water vapor corrosion of equipment; in low-temperature areas, it can also cause equipment freezing. 3. Heating the raw material gas using traditional tubular heaters is energy-intensive: MIDREX, HYLIII, PERED, and ENERGIRON-ZR processes use fuel to heat the outer wall of the furnace tubes, thereby heating the reducing gas inside the tubes, and recovering waste heat from the flue gas through heat exchangers. This heating method is energy-intensive. These shortcomings severely restrict the promotion and application of existing gas-based vertical shaft furnace direct reduction processes in my country. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a direct reduction method for a gas-based vertical shaft furnace using coke oven gas or coal gas as the gas source. This method eliminates the need for reforming, oxygen production, and oxygen-enriched heating processes, reducing investment and operating costs; it minimizes the amount of easily carbon-depositing gas requiring heating, and ensures normal production operation by employing measures such as heating a small amount of this gas separately, regularly cleaning carbon deposits, and alternating operation of two or more independent heating furnaces; it effectively reduces energy consumption in the direct reduction process of the gas-based vertical shaft furnace; and it reduces water consumption. Other objectives of this invention will be pointed out later or will be obvious to those skilled in the art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for direct reduction in a gas-based vertical shaft furnace includes adding iron oxides of a certain particle size to the gas-based vertical shaft furnace through a top charging device; purifying the raw coal gas produced by the vertical shaft furnace into purified coal gas; heating the purified coal gas and raw material gas produced by the vertical shaft furnace and injecting them into the gas-based vertical shaft furnace from outside; in the gas-based vertical shaft furnace, the iron oxides react with the raw material gas and the purified coal gas produced by the vertical shaft furnace to be reduced to direct reduced iron; after passing through the lower cooling section of the gas-based vertical shaft furnace, the iron oxides are discharged outside the furnace; the purified coal gas produced by the vertical shaft furnace is heated by a heating device and injected into the vertical shaft furnace from the reduction section; raw material gas one is injected into the vertical shaft furnace from the lower part of the cooling section; raw material gas two is heated by a heating device two and injected into the vertical shaft furnace from the reduction section; the heating device two includes at least two independent heating furnaces, so that when one furnace is treating carbon deposits, the other furnace can still heat raw material gas two; the raw coal gas produced by the vertical shaft furnace, raw material gas one, and raw material gas two react with the iron oxides in the vertical shaft furnace, and then enters the vertical shaft furnace gas purification device.

[0007] Compared with the prior art, the method of the present invention has the following beneficial effects:

[0008] 1) Simplify processes and reduce overall investment

[0009] Compared with existing gas-based vertical shaft furnace technology, this invention divides the raw gas into two parts. Raw gas one enters the vertical shaft furnace directly without heating, eliminating the external reforming, heating, and oxygen production processes. Raw gas two only has a heating process and no reforming process. Raw gas one and raw gas two complete self-reformation within the vertical shaft furnace, which significantly reduces the overall investment in gas-based vertical shaft furnaces.

[0010] 2) Solved the problem of carbon buildup caused by heating raw gas outside the vertical furnace.

[0011] This invention divides the reducing gas from the vertical shaft furnace into three parts: purified coal gas produced by the furnace itself, raw material gas one, and raw material gas two. These three parts are heated using different methods to address the carbon buildup problem respectively.

[0012] ①Because the purified gas produced by the vertical shaft furnace cannot produce carbon deposits when heated, the purified gas produced by the vertical shaft furnace is heated separately and then injected into the vertical shaft furnace.

[0013] ②The raw material gas is injected directly into the vertical furnace from the lower part of the cooling section without heating. It exchanges heat with the hot reduced iron inside the vertical furnace. While cooling the reduced iron, it is heated by the hot reduced iron, thus avoiding the problem of carbon buildup caused by external heating.

[0014] ③ The above two points have already reduced the amount of raw gas that may produce carbon deposits to a minimum. At this point, for the small amount of raw gas that may produce carbon deposits, at least two sets of heating equipment should be used, one for use and one for backup, so that even if the small amount of raw gas produces carbon deposits, it can be dealt with in time without affecting production.

[0015] 3) This invention uses high-temperature direct reduction iron to heat the raw material gas 1, which saves energy consumption for heating the raw material gas 1;

[0016] 4) It avoids the problem of large amounts of water vapor corroding equipment caused by water cooling of high-temperature direct reduction of iron, and even equipment freezing in low-temperature areas, and also reduces water consumption;

[0017] 5) Compared with existing gas-based vertical shaft furnace technology, this invention eliminates the reforming process and oxygen production process, thus saving gas processing costs such as catalysts, electricity, and labor, and reducing production costs.

[0018] The preferred embodiment of the present invention is as follows:

[0019] The purified coal gas and raw material gas II produced by the vertical shaft furnace are heated by heating device I and heating device II respectively, and then enter the reduction section of the vertical shaft furnace in any of the following ways:

[0020] (1) The heated vertical furnace self-produced purified coal gas and raw material gas 2 enter the vertical furnace from different reducing gas inlets on the reduction section of the gas-based vertical furnace. The inlet of the vertical furnace self-produced purified coal gas on the vertical furnace is located above the inlet of raw material gas 2.

[0021] (2) The heated purified coal gas produced by the vertical shaft furnace and the second raw material gas enter the vertical shaft furnace from different reducing gas inlets on the reduction section of the gas-based vertical shaft furnace. The inlet of the purified coal gas produced by the vertical shaft furnace is located below the inlet of the second raw material gas.

[0022] (3) The purified coal gas produced by the heated vertical furnace and the raw material gas are mixed and then enter the reducing gas inlet of the reduction section of the vertical furnace.

[0023] (4) The heated vertical furnace produces purified coal gas and raw material gas, which enter each reducing gas inlet on the reduction section of the vertical furnace through two pipelines.

[0024] The temperature at which the self-produced purified coal gas and raw material gas 2 enter the vertical shaft furnace is 900-1050℃, and the temperature at which the self-produced purified coal gas enters the vertical shaft furnace is less than or equal to the temperature at which the raw material gas 2 enters the vertical shaft furnace.

[0025] All the crude gas produced by the vertical shaft furnace is purified into purified gas, which is then recycled within the furnace itself.

[0026] Both the heating device one for heating the purified coal gas produced by the vertical furnace and the heating device two for heating the raw material gas adopt regenerative heating technology.

[0027] When the heated purified coal gas produced by the vertical shaft furnace and the second raw material gas enter the same reducing gas inlet on the reduction section of the vertical shaft furnace from two separate pipelines, the pipeline carrying the hot raw material gas enters from the side of the pipeline carrying the hot purified coal gas of the vertical shaft furnace and extends out from the pipe opening.

[0028] The heating method for the purified coal gas and raw material gas No. 2 produced by the vertical shaft furnace shall be one of the following:

[0029] (1) The purified coal gas and raw material gas produced by the vertical furnace are heated by the heat storage body in the heat storage heating device 1 and the heat storage heating device 2, respectively.

[0030] (2) The purified coal gas and raw material gas produced by the vertical furnace are heated by the high-temperature resistant tubes in the regenerative heating device 1 and the regenerative heating device 2, respectively. That is, the heat storage body in the regenerative heating device 1 and the regenerative heating device 2 is used to heat the air, or heat the air and fuel gas respectively. The high-temperature resistant tube in the combustion chamber is heated by the combustion of air and fuel gas. The high-temperature resistant tube is filled with the purified coal gas or raw material gas produced by the vertical furnace.

[0031] (3) The purified coal gas produced by the vertical furnace is heated by the heat storage body in the first heat storage heating device, and the raw material gas is heated by the high temperature resistant tube in the second heat storage heating device.

[0032] (4) The purified coal gas produced by the vertical furnace is heated by the high-temperature resistant tube in the first heat storage heating device, and the raw material gas is heated by the heat storage body in the second heat storage heating device.

[0033] When the purified coal gas or raw material gas produced by the vertical shaft furnace is heated by the heat storage body, either heat storage heating device 1 or heat storage heating device 2 includes three independent heat storage heating furnaces; when the purified coal gas or raw material gas produced by the vertical shaft furnace is heated by the high temperature resistant tube, either heat storage heating device 1 or heat storage heating device 2 includes two independent heat storage heating furnaces.

[0034] Each independent heating furnace in heating device two has a reducing gas inlet pipe connected to a gas pipeline for cleaning carbon deposits, and a reducing gas outlet pipe connected to a pipeline for discharging waste gas generated during the cleaning of carbon deposits. Carbon deposits are cleaned by introducing high-temperature steam and / or air into the gas pipeline for cleaning carbon deposits.

[0035] When the second raw material gas is heated by a heat storage body, the heat storage body can be removed, the carbon deposits on the heat storage body material can be cleaned, and then it can be put back into the second heat storage heating device for reuse.

[0036] Compared with the prior art, the preferred embodiment of the present invention has the following beneficial effects:

[0037] 1) Because all the raw gas is purified into purified gas produced in the vertical shaft furnace, heated separately, and then returned to the furnace, the amount of raw gas that may produce carbon deposits is further reduced, thus lowering the cost of carbon deposit treatment. Existing technology uses 1 / 3 of the self-produced gas as fuel.

[0038] 2) Unlike traditional tubular furnaces, this invention uses regenerative combustion technology, which is more energy-efficient.

[0039] 3) The heat storage material of the regenerative heating furnace used in this invention can be removed, making it easier to remove carbon deposits from the heat storage material;

[0040] Existing gas-based vertical shaft furnace processes all use natural gas as feedstock. However, China's fuel resources are characterized by a scarcity of natural gas and an abundance of coal. The most usable gas sources are coke oven gas and coal-to-gas. However, technologies using coke oven gas and coal-to-gas as feedstock cannot be applied to gas-based vertical shaft furnace processes using natural gas as the gas source. Coke oven gas and coal-to-gas are more prone to carbon buildup during heating, affecting normal production operations and potentially causing serious accidents. The overall technology of this invention solves the problems of carbon buildup, high investment costs, unreasonable energy consumption, and high operating costs, thus offering significant advantages over existing processes. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of a process for direct reduction of gas-based vertical shaft furnace according to the present invention. The inlet of the purified coal gas produced by the vertical shaft furnace is located above the second inlet of the raw material gas.

[0042] Figure 2 A schematic diagram of a heating device 1 for heating purified coal gas produced by a vertical shaft furnace by a heat storage body;

[0043] Figure 3 A schematic diagram of a heating device 1 for heating purified coal gas produced by a vertical shaft furnace by high-temperature resistant tubes;

[0044] Figure 4 A schematic diagram of heating device 2, in which the raw material gas 2 is heated by the heat storage body;

[0045] Figure 5 This is a schematic diagram of heating device 2, in which the raw material gas 2 is heated by a high-temperature resistant tube;

[0046] Figure 6 This is another schematic diagram of the direct reduction process of the gas-based vertical shaft furnace of the present invention. The inlet of the purified coal gas produced by the vertical shaft furnace is located below the second inlet of the raw material gas.

[0047] Figure 7 This is another schematic diagram of the direct reduction process of the gas-based vertical shaft furnace of the present invention. The purified coal gas produced by the vertical shaft furnace and the raw material gas are mixed and then enter the vertical shaft furnace.

[0048] Figure 8 This is another schematic diagram of the direct reduction process of the gas-based vertical shaft furnace of the present invention. The purified coal gas produced by the vertical shaft furnace and the raw material gas II are respectively introduced into each reducing gas inlet on the reduction section of the vertical shaft furnace through two pipelines.

[0049] The diagram is labeled as follows: 1-Vertical furnace preheating section, 2-Vertical furnace reduction section, 3-Vertical furnace cooling section, 4-Vertical furnace body, 41-Vertical furnace reducing gas inlet 1, 42-Vertical furnace reducing gas inlet 2, 43-Vertical furnace reducing gas inlet 3, 5-Discharge device, 6-Raw material gas 1, 7-Raw material gas 2, 8-Heating device 2, 81-Regenerator furnace 2, 82-High temperature resistant tube furnace 2, 84-Gas pipeline for cleaning carbon deposits in heating device 2, 85-Exhaust gas pipeline for discharging carbon deposits in heating device 2, 86-Flue of heating device 2, 87-Reducing gas inlet pipeline of heating device 2, 88-Reducing gas outlet pipeline of heating device 2, 811-Combustion chamber of regenerator furnace 2, 812-Regenerator chamber of regenerator furnace 2, 813-Air nozzle of regenerator furnace 2, 814-Gas nozzle of regenerator furnace 2, 815- 816 - Reduction gas inlet pipe of regenerator 2; 817 - Reduction gas outlet pipe of regenerator 2; 818 - Flue of regenerator 2; 819 - Gas pipe for cleaning carbon deposits of regenerator 2; 8121 - Pipeline for discharging waste gas generated from cleaning carbon deposits of regenerator 2; 8122 - Regenerator in the regenerator chamber of regenerator 2; 8151 - Valve on the reduction gas inlet pipe of regenerator 2; 8161 - Regenerator 2... Valves on the reducing gas outlet pipeline; 8171 - Flue valve of the second regenerator furnace; 8181 - Valves on the gas pipeline for cleaning carbon deposits in the second regenerator furnace; 8191 - Valves on the pipeline for emitting exhaust gas generated from cleaning carbon deposits in the second regenerator furnace; 821 - Combustion chamber of the second high-temperature tube furnace; 822 - Regenerator chamber of the second high-temperature tube furnace; 823 - Air pipeline of the second high-temperature tube furnace; 824 - Gas pipeline of the second high-temperature tube furnace; 825 - Reducing gas inlet pipeline of the second high-temperature tube furnace; 826 - 827 - Reduction gas outlet pipeline of high-temperature resistant tube heater II; 828 - Flue of high-temperature resistant tube heater II; 829 - Gas pipeline for cleaning carbon deposits of high-temperature resistant tube heater II; 820 - Pipeline for discharging waste gas generated from cleaning carbon deposits of high-temperature resistant tube heater II; 8211 - Reversing valve of high-temperature resistant tube heater II; 8221 - High-temperature resistant tube in combustion chamber of high-temperature resistant tube heater II; 8251 - Heat storage medium in heat storage chamber of high-temperature resistant tube heater II; 8261 - Valve on reduction gas inlet pipeline of high-temperature resistant tube heater II; Valves on the reducing gas outlet pipeline of the high-temperature tube heater II; 8271 - Flue valve of the high-temperature tube heater II; 8281 - Valves on the gas pipeline for cleaning carbon deposits in the high-temperature tube heater II; 8291 - Valves on the pipeline for discharging waste gas generated from cleaning carbon deposits in the high-temperature tube heater II; 9 - Heating device I; 91 - Regenerator heater I; 93 - Flue of heating device I; 94 - Reducing gas inlet pipeline of heating device I; 95 - Reducing gas outlet pipeline of heating device I; 911 - Combustion chamber of regenerator heater I.912 - Regenerator chamber of regenerator 1, 913 - Air nozzle of regenerator 1, 914 - Gas nozzle of regenerator 1, 915 - Reducing gas inlet pipe of regenerator 1, 916 - Reducing gas outlet pipe of regenerator 1, 917 - Flue of regenerator 1, 9121 - Regenerator in regenerator chamber of regenerator 1, 9151 - Valve on reducing gas inlet pipe of regenerator 1, 9161 - Valve on reducing gas outlet pipe of regenerator 1, 9171 - Flue valve of regenerator 1, 921 - Combustion chamber of high-temperature tube regenerator 1, 922 - Regenerator chamber of high-temperature tube regenerator 1, 923 - Air pipe of high-temperature tube regenerator 1, 924 - Gas pipe of high-temperature tube regenerator 1, 925 - Reducing gas inlet pipe of high-temperature tube regenerator 1, 926 - 927 - Reducing gas outlet pipeline of high-temperature tube heater 1; 920 - Flue of high-temperature tube heater 1; 9211 - Reducing valve of high-temperature tube heater 1; 9221 - High-temperature tube in combustion chamber of high-temperature tube heater 1; 10 - Heat storage medium in heat storage chamber of high-temperature tube heater 1; 11 - Gas purification device; 12 - Reduced iron; 13 - Charging device; 14 - Purified gas produced by the vertical shaft furnace. Detailed Implementation

[0050] To fully understand the purpose, features and effects of the present invention, the present invention will be described in detail through the following specific embodiments, but the present invention is not limited thereto.

[0051] Please see Figure 1 , Figure 1The present invention provides a process for direct reduction in a gas-based vertical shaft furnace, comprising: adding iron oxide with a particle size of 8-16mm into the gas-based vertical shaft furnace 4 through the top charging device 12; the raw coal gas produced by the vertical shaft furnace undergoing a series of gas purification devices 10 for dust removal, dehydration, desulfurization, and carbon dioxide removal to become purified coal gas 13 produced by the vertical shaft furnace; the purified coal gas 13 enters the heating device 9 through the reducing gas inlet pipe 94 of the heating device 9; after being heated by the heating device 9, it is injected into the vertical shaft furnace 4 through the outlet pipe 95 from the reducing gas inlet 41 of the gas-based vertical shaft furnace reduction section 2; and the raw material gas 7... The reducing gas enters the heating device 28 through the reducing gas inlet pipe 87. After being heated by the heating device 28, it is injected into the vertical furnace 4 through the outlet pipe 88 from the vertical furnace reducing gas inlet 42 below the vertical furnace reducing gas inlet 41 of the gas-based vertical furnace reduction section 2. The raw material gas 6 is injected into the vertical furnace 4 from the vertical furnace reducing gas inlet 3 43 at the bottom of the vertical furnace cooling section 3 without heating. The iron oxides, high-temperature self-produced purified coal gas 13, raw material gas 16 and raw material gas 27 are added to the vertical furnace 4 from the furnace top charging device 12. In reverse operation, iron oxides are gradually heated in the upper preheating section 1 and reduction section 2 of the vertical shaft furnace, and simultaneously react with high-temperature self-produced purified coal gas 13, raw material gas 2 7, and raw material gas 1 6, being reduced to high-temperature reduced iron. The gas from the reaction of the self-produced purified coal gas 13, raw material gas 2 7, and raw material gas 1 6 with the iron oxides passes through the upper preheating section 1 of the vertical shaft furnace, where its temperature decreases to 350-500℃, forming self-produced crude coal gas. This crude coal gas enters the vertical shaft furnace gas purification device 10 via the furnace top gas pipeline. The high-temperature reduced iron in the reduction section 2 continues downward into the cooling section 3, reacting with raw material gas 1 6 injected from the lower part of the cooling section 3, further increasing the metallization rate and carburization of the reduced iron. Raw material gas 1 6 gradually cools the reduced iron 11, which then passes through the lower cooling section 3 of the gas-based vertical shaft furnace and is discharged from the furnace via the discharge device 5. Simultaneously, the high-temperature reduced iron cools the raw material gas 1 6. The heated raw material gas 6 and the gas produced after reacting with high-temperature reduced iron gradually enter the reduction section 2 and the upper preheating section 1 of the vertical shaft furnace to continue participating in the chemical reactions of the substances in the reduction section 2 and the upper preheating section 1. During the entire reaction process in the vertical shaft furnace, the hydrocarbons in raw material gas 6 and raw material gas 7 are reformed into reducing gases hydrogen and carbon monoxide under the catalysis of reduced iron, and participate in the reduction reaction of iron oxides. Ethylene, acetylene, BTX, tar and naphthalene, which are prone to carbon deposition, in raw material gas 6 and raw material gas 7 are removed.

[0052] The heating device for the self-produced purified coal gas in the vertical shaft furnace adopts any of the following heating methods: ① The self-produced purified coal gas in the vertical shaft furnace is heated by the heat storage body in the heat storage chamber. This is called heat storage body heating device one, and the heating furnace inside heat storage body heating device one is called heat storage body heating furnace one; ② The self-produced purified coal gas in the vertical shaft furnace is heated by the high-temperature resistant tubes in the heat storage chamber. This is called high-temperature resistant tube heating device one, and the heating furnace inside high-temperature resistant tube heating device one is called high-temperature resistant tube heating furnace one. Please refer to [link / reference]. Figure 2 and Figure 3 .

[0053] Figure 2 This is a schematic diagram of a heating device 91 for heating purified coal gas produced by a vertical shaft furnace by a heat storage medium. When the purified coal gas produced by the vertical shaft furnace is heated by a heat storage medium, the heating device 91 includes three parallel independent heat storage medium heaters 91. The three independent heat storage medium heaters 91 have the same structure. The three reducing gas inlet pipes 915, three outlet pipes 916, and three flues 917 of the three independent heat storage medium heaters 91 are respectively connected to form the reducing gas inlet pipe 94, the outlet pipe 95, and the flue 93 of the heating device 91. The reducing gas inlet pipe 915, the outlet pipe 916, and the flue 917 of each independent heat storage medium heater 91 are respectively connected to form the reducing gas inlet pipe 94, the outlet pipe 95, and the flue 93 of the heating device 91. Each unit has a reducing gas inlet valve 9151, an outlet valve 9161, and a flue valve 9171. One end of the regenerator chamber 912 of each independent regenerator furnace 91 is connected to the combustion chamber 911, and the other end is connected to the reducing gas inlet pipe 915 and the flue 917 of the regenerator furnace 91. The combustion chamber 911 is connected to the air nozzle 913, the gas nozzle 914, and the reducing gas outlet pipe 916 of the regenerator furnace 91. The regenerator chamber 912 contains a regenerator 9121. Figure 2 The images shown, from left to right, are the first regenerator heater 91, the second regenerator heater 91, and the third regenerator heater 91.

[0054] Figure 3 This is a schematic diagram of a heating device 1 for heating purified coal gas produced by a vertical shaft furnace using high-temperature resistant pipes. When the purified coal gas is heated using high-temperature resistant pipes, the heating device 1 9 includes a combustion chamber 921, two regenerator chambers 922, a regenerator 9221, a high-temperature resistant pipe 9211, a gas pipeline 924, an air pipeline 923, a flue 927, and a reversing valve 920. Figure 3As shown, the two heat storage chambers 922 are, from left to right, the first heat storage chamber 922 and the second heat storage chamber 922, and the two heat storage chambers have the same structure. The combustion chamber 921 is connected to a heat storage chamber 922 and a gas pipeline 924 on both sides. The heat storage body 9221 is installed in the heat storage chamber 922. The other end of the heat storage chamber 922 is provided with an air pipeline 923 and a flue 927. The two heat storage chambers 922 are connected to the air pipeline 923 and the flue 927 by a reversing valve 920. The high-temperature resistant pipe 9211 is located inside the combustion chamber 921. The reducing gas inlet pipe 925 and the outlet pipe 926 of the high-temperature resistant pipe 9211 are located outside the combustion chamber 921. The reducing gas inlet pipe 925 of the high-temperature resistant pipe 9211 is connected to the reducing gas inlet pipe 94 of the heating device 9. The reducing gas outlet pipe 926 is connected to the reducing gas outlet pipe 95 of the heating device 9. The flue 927 is connected to the flue 93 of the heating device 9.

[0055] The heating device 2 for raw material gas 2 adopts any of the following heating methods: ① The method in which raw material gas 2 is heated by the heat storage body in the heat storage chamber is called heat storage body heating device 2, and the heating furnace inside heat storage body heating device 2 is called heat storage body heating furnace 2; ② The method in which raw material gas 2 is heated by the high-temperature resistant tube in the heat storage chamber is called high-temperature resistant tube heating device 2, and the heating furnace inside high-temperature resistant tube heating device 2 is called high-temperature resistant tube heating furnace 2. Please refer to [link / reference]. Figure 4 and Figure 5 .

[0056] Figure 4This is a schematic diagram of heating device 2, in which raw material gas 2 is heated by a heat storage medium. When raw material gas 2 is heated by a heat storage medium, heating device 2 8 includes three parallel independent heat storage medium heaters 2 81. The three independent heat storage medium heaters 2 81 have the same structure. The three reducing gas inlet pipes 815, three outlet pipes 816, and three flues 817 of the three independent heat storage medium heaters 2 81 are respectively connected to form the reducing gas inlet pipe 87, outlet pipe 88, and flue 86 of heating device 2 8. Each independent heat storage medium heater 2 81 The reducing gas inlet pipe 815, outlet pipe 816, and flue 817 are all equipped with reducing gas inlet pipe valve 8151, outlet pipe valve 8161, and flue valve 8171. One end of the regenerator chamber 812 of each independent regenerator furnace 81 is connected to the combustion chamber 811, and the other end is connected to the reducing gas inlet pipe 815 and the flue 817 of the regenerator furnace 811. The combustion chamber 811 is connected to the air nozzle 813 and the gas nozzle 814, as well as the regenerator furnace 811. The reducing gas outlet pipe 816 is provided. A heat storage chamber 812 contains a heat storage body 8121. A heat storage body outlet 8122 is located at the bottom of the heat storage chamber 812. The reducing gas inlet pipe 815 of each independent heat storage furnace 81 is connected to a gas pipeline 818 for cleaning carbon deposits. Pipeline 818 is located between the reducing gas inlet pipe valve 8151 and the heat storage furnace 81. A valve 8181 is installed on pipe 818. The three gas pipelines 818 for cleaning carbon deposits of the three independent heat storage furnaces 81 are connected in parallel to form a heating system. The gas pipeline 84 for cleaning carbon deposits in heating device 2 8 is connected to the reducing gas outlet pipeline 816 of each independent regenerator heater 2 81, and is connected to a pipeline 819 for discharging waste gas generated from cleaning carbon deposits. Pipeline 819 is located between the reducing gas outlet pipeline valve 8161 and the regenerator heater 2 81, and is equipped with a valve 8191. The three pipelines 819 for discharging waste gas generated from cleaning carbon deposits from the three independent regenerator heaters 2 81 are connected in parallel and combined to form pipeline 85 for discharging waste gas generated from cleaning carbon deposits in heating device 2 8. Figure 4 The images shown, from left to right, are the first regenerator furnace 2, the second regenerator furnace 2, and the third regenerator furnace 2, respectively.

[0057] Figure 5This is a schematic diagram of heating device 2, in which raw material gas 2 is heated by high-temperature resistant tubes. When raw material gas 2 is heated by high-temperature resistant tubes, heating device 2 8 consists of two independent high-temperature resistant tube heating furnaces 2 82 connected in parallel. The two independent high-temperature resistant tube heating furnaces 2 82 have the same structure. The two reducing gas inlet pipes 825, the two outlet pipes 826, and the two flues 827 of the two independent high-temperature resistant tube heating furnaces 2 82 are respectively connected to form the reducing gas inlet pipe 87, the outlet pipe 88, and the flue 86 of heating device 2 8. Each independent high-temperature resistant tube heating furnace 2 82 has a reducing gas inlet pipe valve 8251, an outlet pipe valve 8261, and a flue valve 8271 in its reducing gas inlet pipe 825, outlet pipe 826, and flue 827. Each high-temperature resistant tube heater 82 includes a combustion chamber 821, two regenerator chambers 822, a regenerator 8221, a high-temperature resistant tube 8211, a gas pipeline 824, an air pipeline 823, a flue 827, and a reversing valve 820. (According to...) Figure 5 As shown, the two regenerators 822, from left to right, are the first regenerator 822 and the second regenerator 822, and both regenerators have the same structure. Each side of the combustion chamber 821 is connected to a regenerator 822 and a gas pipeline 824. The heat storage body 8221 is installed inside the regenerator 822, and an air pipeline 823 is provided at the other end of the regenerator 822. The flue 827 and the two regenerators 822 are connected to the air pipe 823 and the flue 827 by a reversing valve 820. The high-temperature resistant tube 8211 is located inside the combustion chamber 821. The reducing gas inlet pipe 825 and the outlet pipe 826 of the high-temperature resistant tube 8211 are located outside the combustion chamber 821. The reducing gas inlet pipe 825 of each independent high-temperature resistant tube heater 82 is connected to the gas pipe 828 for cleaning carbon deposits. The pipe 828 is located between the reducing gas inlet pipe valve 8251 and the high-temperature resistant tube heater 822. The pipe 828 is equipped with a valve 8281. The two independent high-temperature resistant tube heaters 821 and 822 are connected to the air pipe 823 and the air pipe 8211. Two parallel gas pipelines 828 for cleaning carbon deposits from heating device 2 are connected to form gas pipeline 84 for cleaning carbon deposits from heating device 2. A pipeline 829 for discharging waste gas generated from cleaning carbon deposits is connected to the reducing gas outlet pipeline 826 of each independent high-temperature tube heating furnace 2. Pipeline 829 is located between valve 8261 of the reducing gas outlet pipeline and high-temperature tube heating furnace 2, and valve 8291 is installed on pipeline 829. The two parallel parallel gas discharge pipelines 829 of the two independent high-temperature tube heating furnaces 2 are connected to form gas discharge pipeline 85 for cleaning carbon deposits from heating device 2. Figure 5 The images shown, from left to right, are the first high-temperature resistant tube heating furnace 2, type 82, and the second high-temperature resistant tube heating furnace 2, type 82.

[0058] Example 1

[0059] Please see Figure 2 , Figure 4 and Figure 6Coke oven gas is used as feedstock gas one and feedstock gas two. The purified gas produced by the vertical shaft furnace and feedstock gas two are heated to a temperature of 1000℃. The purified gas produced by the vertical shaft furnace and feedstock gas two are heated by heat storage bodies in heating device one and heating device two, respectively. The inlet of the purified gas produced by the vertical shaft furnace is located below the inlet of feedstock gas two. Heating device two includes three independent heating furnaces. The method of direct reduction of gas-based vertical shaft furnace is as follows:

[0060] Iron oxide particles with a size of 8-16mm are added to the gas-based vertical shaft furnace 4 through the top charging device 12. The raw coal gas produced by the furnace undergoes a series of purification processes (dust removal, dehydration, desulfurization, and carbon dioxide removal) by the gas purification device 10, resulting in purified coal gas 13. This purified coal gas 13 enters the heating device 9 through the reducing gas inlet pipe 94. After being heated to approximately 1000℃, it is injected into the vertical shaft furnace 4 through the outlet pipe 95 from the reducing gas inlet 42 below the reducing gas inlet 41 in the reducing section 2 of the gas-based vertical shaft furnace. The amount of purified coal gas 13 produced by the furnace is approximately 1150 M³. 3 / t·reduced iron, the amount of coke oven gas required for raw material gas 27 is approximately 180M. 3 / t·reduced iron, raw material gas 27 enters heating device 28 through reducing gas inlet pipe 87, and is heated to about 1000℃ by heating device 28. After being discharged through outlet pipe 88, it is injected into vertical furnace 4 from vertical furnace reducing gas inlet 41 of gas-based vertical furnace reducing section 2. Raw material gas 6 is injected into vertical furnace 4 from vertical furnace reducing gas inlet 3 43 at the lower part of vertical furnace cooling section 3 without heating. The amount of coke oven gas required for raw material gas 6 is about 220M 3 / t·reduced iron; Inside the vertical shaft furnace 4, iron oxides added from the top charging device 12 flow counter-currently with high-temperature self-produced purified coal gas 13, raw material gas 16, and raw material gas 27. The iron oxides are gradually heated through the upper preheating section 1 and reduction section 2 of the vertical shaft furnace, and simultaneously react with the high-temperature self-produced purified coal gas 13, raw material gas 27, and raw material gas 16, being reduced to high-temperature reduced iron. The gas after the reaction of the self-produced purified coal gas 13, raw material gas 27, and raw material gas 16 with the iron oxides passes through the upper preheating section 1 of the vertical shaft furnace, where the temperature drops to 350-500℃, forming self-produced crude coal gas. The self-produced crude coal gas enters the vertical shaft furnace gas purification device 10 through the top coal gas pipeline. The high-temperature reduced iron in the reduction section 2 of the vertical shaft furnace continues to flow downward into the cooling section 3, where it is injected from the lower part of the cooling section 3. The reaction of raw material gas 6 further improves the metallization rate of reduced iron and increases the carburization of reduced iron. Raw material gas 6 gradually cools reduced iron 11, which passes through the lower cooling section 3 of the gas-based vertical shaft furnace and is then discharged from the furnace through the discharge device 5. At the same time, the high-temperature reduced iron heats raw material gas 6. The heated raw material gas 6 and the gas produced by its reaction with the high-temperature reduced iron gradually enter the reduction section 2 and the upper preheating section 1 of the vertical shaft furnace to continue to participate in the chemical reaction of the substances in the reduction section 2 and the upper preheating section 1. During the entire reaction process in the vertical shaft furnace, the hydrocarbons in raw material gas 6 and raw material gas 7 are reformed into reducing gases hydrogen and carbon monoxide under the catalysis of reduced iron, which participate in the reduction reaction of iron oxides. At the same time, components such as ethylene, acetylene, BTX, tar and naphthalene that are prone to carbon deposition are removed.

[0061] Heating process of heating device 9: Heating device 9 has three identical independent regenerator heaters 91, all of which use regenerator 9121 to heat the purified coal gas 13 produced by the vertical furnace. The reducing gas inlet pipe 94 and outlet pipe 95 of the three independent regenerator heaters 91 connected in parallel are respectively connected to the purified coal gas 13 produced by the vertical furnace and the reducing gas inlet 42 of the vertical furnace reducing section 2 of the gas-based vertical furnace. Each independent heater 9 has an inlet pipe valve 9151 and an outlet pipe valve 9161 for its reducing gas inlet pipe 915 and outlet pipe 916. The three independent regenerator heaters 91 are simultaneously in the following states: heating the self-produced purified coal gas 13 in the vertical furnace, heating the regenerator chamber 912 in combustion, and shut-in state. That is, the heating process of the heating device 91 goes through three steps: (1) when the second regenerator heater 91 is heating the regenerator 9121 in the regenerator chamber 912 and enters the regenerator state, the third regenerator heater 91 completes the regenerator state and is shut-in state, while the first regenerator heater 91 is in the state of heating the self-produced purified coal gas 13 in the vertical furnace; (2) when the third regenerator heater 91 is heating the self-produced purified coal gas 13 in the vertical furnace, the third regenerator heater 91 completes the regenerator state and is shut-in state, while the first regenerator heater 91 is in the state of heating the self-produced purified coal gas 13 in the vertical furnace; When the hot furnace 91 heats the vertical furnace to produce purified coal gas 13, the first heat storage furnace 91 burns and heats the heat storage body 9121 in the heat storage chamber 912 to store heat. The second heat storage furnace 91 completes the heat storage in the heat storage chamber 912 and is in a stale state. (3) When the second heat storage furnace 91 heats the vertical furnace to produce purified coal gas 13, the third heat storage furnace 91 burns and heats the heat storage body 9121 in the heat storage chamber 912 to store heat. The first heat storage furnace 91 completes the heat storage in the heat storage chamber 912 and is in a stale state.The process flow of the above-mentioned heating device 9(1) is further described below: The process of the second heat storage furnace 91 combustion heating heat storage chamber is as follows: First, the air nozzle 913 and gas nozzle 914 of the combustion chamber 911 of the second heat storage furnace 91 are opened, so that the hot flue gas generated by the combustion of air and gas heats the heat storage body 9121 in the heat storage chamber 912. The flue gas that has cooled down after flowing through the heat storage chamber 912 is discharged through the flue 917. When the temperature of the heat storage chamber 912 reaches the specified requirements, the heat storage of the heat storage chamber 912 is completed; The process of the third heat storage furnace 91 shutting down is as follows: After the heat storage of the heat storage chamber 912 is completed, the air nozzle 913 and gas nozzle 914 are closed. The valve 9171 of the flue 917 is used to enter the stale state. The process of heating the self-produced purified coal gas 13 of the vertical furnace by the first regenerator heater 91 is as follows: the valve 9151 of the reducing gas inlet pipe 915 and the valve 9161 of the outlet pipe 916 of the first regenerator heater 91 in the stale state are opened. The self-produced purified coal gas 13 of the vertical furnace enters from the reducing gas inlet pipe 915 of the first regenerator heater 91 through the reducing gas inlet pipe 94 of the heating device 9. After being heated by the regenerator 9121 in the regenerator chamber 912, it is discharged from the reducing gas outlet pipe 916. The discharged hot self-produced purified coal gas of the vertical furnace enters the vertical furnace 4 through the reducing gas outlet pipe 95 of the heating device 9 and the reducing gas inlet 42 of the vertical furnace. The principle of (2) and (3) in the three process flow of the heating device 9 is the same as that of (1), and will not be described here. After the heating device 9 completes the three process flow, it continues to cycle through the three process flow.

[0062] Heating process of heating device 28: Heating device 28 has three identical independent regenerator heaters 281, all of which use regenerator 8121 to heat raw material gas 27. The regenerator 8121 is located in the regenerator chamber 812. The reducing gas inlet pipe 87 and outlet pipe 88 of the three independent regenerator heaters 281 connected in parallel are respectively connected to the raw material gas 27 pipe and the reducing gas inlet 41 of the vertical furnace of the gas-based vertical furnace reduction section 2. Each independent regenerator heater 281 has a reducing gas inlet pipe valve 8151 and an outlet pipe valve 8161 on its inlet pipe 815 and outlet pipe 816. The three independent regenerator heaters 281 are simultaneously in the following states: heating raw material gas 27, combustion heating regenerator chamber 812, and shut-in state. That is, the heating device 28 goes through three processes: (1) when the second regenerator heater 281 enters the regenerator state by combustion heating regenerator 8121 in the regenerator chamber 812, the third regenerator heater 281 completes the regenerator state and is shut-in, while the first regenerator heater 281 is in the state of heating raw material gas 27; (2) when the third regenerator heater 281 enters the state of combustion heating regenerator chamber 812, the third regenerator heater 281 completes the regenerator state and is shut-in state, while the first regenerator heater 281 is in the state of heating raw material gas 27; When the second heat storage furnace 81 heats the raw material gas 7, the first heat storage furnace 81 burns and heats the heat storage body 8121 in the heat storage chamber 812 to store heat. The second heat storage furnace 81 completes the heat storage in the heat storage chamber 812 and is in a closed state. (3) When the second heat storage furnace 81 heats the raw material gas 7, the third heat storage furnace 81 burns and heats the heat storage body 8121 in the heat storage chamber 812 to store heat. The first heat storage furnace 81 completes the heat storage in the heat storage chamber 812 and is in a closed state.The process flow of the above-mentioned heating device 2 8(1) is further described below: The process of the second heat storage furnace 2 81 combustion heating heat storage chamber is as follows: First, close the valve 8151 of the reducing gas inlet pipe 815 of the second heat storage furnace 2 81 and the valve 8181 on the gas pipe 818 for cleaning carbon deposits. Open the valve 8171 of the flue 817. Close the valve 8161 of the reducing gas outlet pipe and the valve 8191 of the carbon deposit exhaust pipe 819. Then, open the air nozzle 813 and the gas nozzle 814 of the combustion chamber 811 of the second heat storage furnace 2 81. The hot flue gas generated by the combustion of air and gas heats the heat storage body 8121 of the heat storage chamber 812. The cooled flue gas is discharged through the flue 817. When the temperature of the heat storage chamber 812 reaches the specified requirements, the heat storage is completed. The process of heat storage in chamber 812 is as follows: After heat storage in the heat storage chamber 812 is completed, the air nozzle 813, gas nozzle 814 and flue valve 8171 of flue 817 are closed, and the furnace is put into a closed state. The process of heating raw material gas 7 in the first heat storage furnace 81 is as follows: The reducing gas inlet pipe valve 8151 and the outlet pipe valve 8161 of the first heat storage furnace 81 in the closed state are opened. Raw material gas 7 enters from the reducing gas inlet pipe 815 of the first heat storage furnace 81, is heated by the heat storage body 8121 in the heat storage chamber 812, and is discharged from the reducing gas outlet pipe 816. The discharged hot raw material gas 7 enters the vertical furnace 4 from the reducing gas inlet 41 of the vertical furnace through the reducing gas outlet pipe 88 of the heating device 8. The principle of (2) and (3) in the three processes of the heating device 8 above is the same as that of (1), and will not be described here. After the heating device completes the three process steps, it continues to cycle through these three process steps.

[0063] The process of cleaning carbon deposits in heating device 28: When cleaning carbon deposits in the first regenerator furnace 281, the other two regenerator furnaces 281 are responsible for heating the raw material gas 27. First, close the valve 8151 of the reducing gas inlet pipe 815, the valve 8171 of the flue 817, and the valve 8161 of the reducing gas outlet pipe 816 of the first regenerator furnace 281. Open the valve 8191 of the exhaust gas pipe 819 for discharging carbon deposits and the valve 8181 on the gas pipe 818 for cleaning carbon deposits. High-temperature steam and / or air are introduced into the pipe 818. As the high-temperature steam and / or air flows through the first regenerator furnace 281, it reacts with the carbon deposits inside the first regenerator furnace 281. The gas after removing the carbon deposits is discharged from the exhaust gas pipe 819 for discharging carbon deposits. After the carbon deposits are cleaned, the first regenerator furnace 281 resumes its working state. Continue cleaning the second regenerator furnace 281 until the carbon deposits in heating device 28 are completely cleaned. When the heat storage furnace 81 has been working for a long time and needs a mid-term overhaul, the heat storage body 8121 can be taken out from the heat storage outlet 8122 at the bottom of the heat storage chamber, the carbon deposits can be cleaned, and then it can be put back for continued use.

[0064] Using the scheme in this embodiment, the amount of coke oven gas that needs to be heated separately is only 1750M³ of the total gas volume of the traditional heating method. 3 The 10% reduction in reduced iron significantly reduces the amount of carbon deposits that may be generated from heating coke oven gas. At the same time, because the three furnaces work alternately, while cleaning the carbon deposits in one furnace, the other two furnaces continue to heat the raw material gas for the vertical furnace, thus not affecting production.

[0065] Example 2

[0066] Please see Figure 1 , Figure 2 and Figure 4 Coke oven gas is used as feedstock gas one and feedstock gas two. Feedstock gas two is heated to 1050℃, and the purified coal gas produced by the vertical shaft furnace is heated to 1000℃. The purified coal gas produced by the vertical shaft furnace and feedstock gas two are heated by the heat storage bodies in heating device one and heating device two, respectively. The inlet of the purified coal gas produced by the vertical shaft furnace is located above the inlet of feedstock gas two. Heating device two includes three independent heating furnaces. The method of direct reduction in the gas-based vertical shaft furnace is as follows:

[0067] Iron oxide particles with a size of 8-16mm are added to the gas-based vertical shaft furnace 4 through the top charging device 12. The raw coal gas produced by the furnace undergoes a series of purification processes (dust removal, dehydration, desulfurization, and carbon dioxide removal) by the gas purification device 10, resulting in purified coal gas 13. This purified coal gas 13 enters the heating device 9 via the reducing gas inlet pipe 94. After being heated to approximately 1000℃ by the heating device 9, it is injected into the vertical shaft furnace 4 through the outlet pipe 95 from the reducing gas inlet 41 of the reduction section 2. The amount of purified coal gas 13 produced by the furnace is approximately 1150 M³. 3 / t·reduced iron, the amount of coke oven gas required for raw material gas 27 is approximately 160M³. 3 / t·reduced iron, raw material gas 27 enters heating device 28 through reducing gas inlet pipe 87, and after being heated to about 1050℃ in heating device 28, it is injected into vertical furnace 4 through outlet pipe 88 from vertical furnace reducing gas inlet 22 below vertical furnace reducing gas inlet 1 41 in gas-based vertical furnace reduction section 2. Raw material gas 6 is injected into vertical furnace 4 from vertical furnace reducing gas inlet 3 43 at the lower part of vertical furnace cooling section 3 without heating. The amount of coke oven gas required for raw material gas 6 is about 240M 3 / t·Reduced Iron; Iron oxides added to the vertical shaft furnace 4 from the top charging device 12 run counter-currently with the high-temperature self-produced purified coal gas 13, raw material gas 16, and raw material gas 27. The iron oxides are gradually heated through the upper preheating section 1 and reduction section 2 of the vertical shaft furnace, and react with the high-temperature self-produced purified coal gas 13, raw material gas 27, and raw material gas 16, and are reduced to high-temperature reduced iron. The gas after the reaction of the self-produced purified coal gas 13, raw material gas 27, and raw material gas 16 with the iron oxides passes through the upper preheating section 1 of the vertical shaft furnace and the temperature drops to 350-500℃, forming the self-produced crude coal gas of the vertical shaft furnace. The self-produced crude coal gas enters the vertical shaft furnace gas purification device 10 through the top coal gas pipeline. The high-temperature reduced iron in the reduction section 2 of the vertical shaft furnace continues to enter the cooling section 3 and reacts with the raw material gas injected from the lower part of the cooling section 3. The reaction of raw gas 16 further improves the metallization rate of reduced iron and increases the carburization of reduced iron. Raw gas 16 gradually cools reduced iron 11, which passes through the lower cooling section 3 of the gas-based vertical shaft furnace and is then discharged from the furnace through the discharge device 5. At the same time, the high-temperature reduced iron heats raw gas 16. The heated raw gas 16 and the gas after reacting with the high-temperature reduced iron gradually enter the reduction section 2 and the upper preheating section 1 of the vertical shaft furnace to continue to participate in the chemical reaction of the substances in the reduction section 2 and the upper preheating section 1. During the entire reaction process in the vertical shaft furnace, the hydrocarbons in raw gas 16 and raw gas 27 are reformed into reducing gases hydrogen and carbon monoxide under the catalysis of reduced iron, which participate in the reduction reaction of iron oxides. At the same time, components such as ethylene, acetylene, BTX, tar and naphthalene that are prone to carbon deposition are removed.

[0068] The heating process of heating device 1 9 and heating device 2 8, as well as the process of cleaning carbon deposits from heating device 2 8, are the same as in Example 1.

[0069] Using the scheme in this embodiment, the amount of coke oven gas that needs to be heated separately is only 1750M³ of the total gas volume of the traditional heating method. 3 The 9% reduction in iron content significantly reduces the amount of carbon deposits that may be generated from heating coke oven gas. Furthermore, because the three furnaces work alternately, even when cleaning carbon deposits in one furnace, the other two furnaces continue to heat the raw material gas for the vertical furnace, thus not affecting production.

[0070] Example 3

[0071] Please see Figure 3 , Figure 5 and Figure 7 Coal gas is used as feedstock gas one and feedstock gas two. The purified coal gas produced by the vertical shaft furnace and feedstock gas two are heated to 950℃. The purified coal gas produced by the vertical shaft furnace and feedstock gas two are heated by high-temperature resistant tubes in heating device one and heating device two, respectively. The purified coal gas produced by the vertical shaft furnace and feedstock gas two are mixed and then enter the vertical shaft furnace. Heating device two includes two independent heating furnaces. The following gas-based vertical shaft furnace direct reduction method is adopted:

[0072] Iron oxide particles with a size of 8-16mm are added to the gas-based vertical shaft furnace 4 through the top charging device 12. The raw coal gas produced by the furnace undergoes a series of purification processes (dust removal, dehydration, desulfurization, and carbon dioxide removal) by the gas purification device 10, resulting in purified coal gas 13. This purified coal gas 13 enters the heating device 9 through the reducing gas inlet pipe 94, where it is heated to approximately 950℃. The volume of purified coal gas 13 produced by the furnace is approximately 1150 M³. 3 / t·reduced iron, the amount of coal gasification required for raw material gas 27 is approximately 250M. 3 / t·reduced iron, raw material gas 27 enters heating device 28 through reducing gas inlet pipe 87, and is heated to about 950℃ in heating device 28. The heated vertical furnace self-purified coal gas 13, which is discharged through outlet pipe 95, is mixed with the heated raw material gas 27, which is discharged through outlet pipe 88, and then injected into vertical furnace 4 from vertical furnace reducing gas inlet 1 41 of gas-based vertical furnace reducing section 2. Raw material gas 16 is injected into vertical furnace 4 from vertical furnace reducing gas inlet 3 43 at the lower part of vertical furnace cooling section 3 without heating. The coal gasification required for raw material gas 16 is about 350M 3 / t·Reduced Iron. Iron oxides added to the vertical shaft furnace 4 from the top charging device 12 run counter-currently with the high-temperature self-produced purified coal gas 13, raw material gas one 6, and raw material gas two 7. The iron oxides are gradually heated through the upper preheating section 1 and reduction section 2 of the vertical shaft furnace, and simultaneously react with the high-temperature self-produced purified coal gas 13, raw material gas two 7, and raw material gas one 6, being reduced to high-temperature reduced iron. The self-produced purified coal gas 13 and raw material gas two 7... After the gas reacts with the iron oxide, the temperature of the gas is reduced to 350-500℃ in the upper preheating section 1 of the vertical shaft furnace, forming raw coal gas produced by the vertical shaft furnace. The raw coal gas is introduced into the vertical shaft furnace gas purification device 10 through the furnace top gas pipeline. The high-temperature reduced iron in the reduction section 2 of the vertical shaft furnace continues to enter the cooling section 3 and reacts with the raw gas injected from the lower part of the cooling section 3 of the vertical shaft furnace, further improving the metallization rate of the reduced iron and increasing the carburization of the reduced iron. The raw gas gradually cools the reduced iron 11 and is discharged from the furnace through the lower cooling section 3 of the gas-based vertical shaft furnace. At the same time, the high-temperature reduced iron heats the raw gas 6. The heated raw gas 6 and the gas after reacting with the high-temperature reduced iron gradually enter the reduction section 2 and the upper preheating section 1 of the vertical shaft furnace to continue to participate in the chemical reaction of the substances in the reduction section 2 and the upper preheating section 1 of the vertical shaft furnace. During the entire reaction process in the vertical furnace, the hydrocarbons in raw material gas 6 and raw material gas 7 are reformed into reducing gases hydrogen and carbon monoxide under the catalysis of reducing iron, and participate in the reduction reaction of iron oxides. At the same time, components such as ethylene, acetylene, BTX, tar and naphthalene that are prone to carbon deposition are removed.

[0073] Heating process of heating device 9: When using high-temperature resistant tubes to heat the self-produced purified coal gas of the vertical furnace, first adjust the reversing valve 920 so that the air in the air pipeline 923 enters the first regenerator 922 through the reversing valve 920. After being heated in the first regenerator 922, it burns with the gas in the gas pipeline 924. The resulting hot flue gas heats the high-temperature resistant tube 9211 in the combustion chamber 921. After heating the high-temperature resistant tube 9211, the hot flue gas enters the second regenerator 922. After cooling in the second regenerator 922, the flue gas exits through the flue through the reversing valve 920. After the discharge of gas 927, the second regenerator 922 completes heat storage. The purified coal gas 13 produced by the vertical furnace enters the high-temperature resistant tube 9211 through the reducing gas inlet pipe 94 of the heating device 19 and the reducing gas inlet pipe 925 of the high-temperature resistant tube 9211. After being heated in the high-temperature resistant tube 9211, it mixes with the raw material gas 27 heated by the heating device 28 through the reducing gas outlet pipe 926 of the high-temperature resistant tube 9211 and the reducing gas discharge pipe 95 of the heating device 19. Then, it enters the vertical furnace 4 through the reducing gas inlet 41 of the vertical furnace. When the temperature in the first regenerator 922 drops to the specified temperature, the reversing valve 920 is reversed, completing one heating cycle and starting the next heating cycle.

[0074] Heating process of heating device 28: Heating device 28 has two identical independent high-temperature tube heating furnaces 282, both of which use high-temperature tubes 8211 to heat raw material gas 27. The reducing gas inlet pipe 87 and outlet pipe 88 of the two independent high-temperature tube heating furnaces 282 connected in parallel are respectively connected to the raw material gas 27 pipe and the heated vertical furnace self-produced purified coal gas 13 pipe. The reducing gas outlet pipe 88 and the heated vertical furnace self-produced purified coal gas 13 pipe merge and are connected to the vertical furnace reducing gas inlet 41 of the gas-based vertical furnace reduction section 2. Each independent high-temperature tube heating furnace 282 has an inlet pipe valve 8251 and an outlet pipe valve 8261 for its reducing gas inlet pipe 825 and outlet pipe 826. Two independent high-temperature tube heaters 82 are simultaneously in heating raw material gas 7 and maintenance states, respectively. When using regenerative high-temperature tube heaters to heat raw material gas 7, valve 8291 on the exhaust gas pipeline 829 for carbon deposits from the high-temperature tube heater 82 and valve 8281 on the gas pipeline 828 for cleaning carbon deposits from the high-temperature tube heater 82 are closed. Valves 8251 on the reducing gas inlet pipeline 825 and 8261 on the reducing gas outlet pipeline 826 of the high-temperature tube heater 82 are opened. The direction of the reversing valve 820 is adjusted so that air in the air pipeline 823 enters the first regenerator chamber 8 through the reversing valve 820. 22. After heat storage in the first heat storage chamber 822, the gas is burned with the gas from the gas pipeline 824, heating the high-temperature resistant pipe 8211 in the combustion chamber 821. The raw material gas 7 entering from the reducing gas inlet pipeline 825 is heated in the high-temperature resistant pipe 8211. The hot flue gas generated by combustion enters the second heat storage chamber 822. The flue gas cooled in the second heat storage chamber 822 is discharged from the flue 827 through the reversing valve 820. After this process, the second heat storage chamber 822 completes heat storage. The heated raw material gas 7 enters the reducing gas outlet pipeline 826, completing one heating cycle. Then the reversing valve 820 is reversed to start the next heating cycle.

[0075] The process of cleaning carbon deposits in heating device 2: Due to the different ash melting points of coal from different origins and coal types, coal gas made from low ash melting point coal types is more likely to contain components that are prone to carbon deposition, and is also more likely to deposit carbon during heating. Therefore, it is necessary to clean the carbon deposits in the heating system of the raw material gas. When cleaning the carbon deposits in the first high-temperature tube heater 82, another high-temperature tube heater 82 is responsible for heating the raw material gas 7. First, close the valve 8251 of the reducing gas inlet pipe 825, the valve 8271 of the flue 827, and the valve 8261 of the reducing gas outlet pipe 826 of the first high-temperature tube heater 82. Open the valve 8291 of the exhaust gas pipe 829 for discharging carbon deposits and the valve 8281 on the gas pipe 828 for cleaning carbon deposits. High-temperature steam and / or air are introduced into the pipe 828. As the high-temperature steam and / or air flows through the first high-temperature tube heater 82, it reacts with the carbon deposits inside the first high-temperature tube heater 82. The gas after removing the carbon deposits is discharged from the exhaust gas pipe 829 for discharging carbon deposits. After the carbon deposits are cleaned, the first high-temperature tube heater 82 resumes its working state, and the cleaning of the second high-temperature tube heater 82 continues.

[0076] Using the scheme of this embodiment, the amount of coal gas that needs to be heated separately is only 15% of the total gas volume of 1750M3 / t·reduced iron in the traditional heating method, which greatly reduces the amount of carbon deposits that may be generated by heating coal gas. At the same time, since the two furnaces work alternately, even when cleaning the carbon deposits in one furnace, the other furnace continues to heat the raw material gas for the vertical furnace, without affecting production.

[0077] Example 4

[0078] Please see Figure 1 , Figure 2 and Figure 5 Coal gas is used as feedstock gas one and feedstock gas two. The heating temperature of the purified coal gas produced by the vertical shaft furnace is 900℃, and the heating temperature of feedstock gas two is 980℃. The purified coal gas produced by the vertical shaft furnace is heated by the heat storage body in heating device one, and feedstock gas two is heated by the high-temperature resistant tube in heating device two. The inlet of the purified coal gas produced by the vertical shaft furnace is located above the inlet of feedstock gas two. Heating device two includes two independent heating furnaces, and the following gas-based vertical shaft furnace direct reduction method is adopted:

[0079] Iron oxide particles with a size of 8-16mm are added to the gas-based vertical shaft furnace 4 through the top charging device 12. The raw coal gas produced by the vertical shaft furnace is purified by a series of coal gas purification devices 10, including dust removal, dehydration, desulfurization, and carbon dioxide removal, becoming purified coal gas 13. All the purified coal gas 13 produced by the vertical shaft furnace enters the heating device 9 through the reducing gas inlet pipe 94. After being heated to about 900℃ by the heating device 9, it is injected into the vertical shaft furnace 4 through the outlet pipe 95 from the reducing gas inlet 41 of the reduction section 2 of the gas-based vertical shaft furnace. The amount of purified coal gas 13 produced by the vertical shaft furnace is about 1150M. 3 / t·reduced iron, the amount of coke oven gas required for raw material gas 27 is approximately 300M 3 / t·reduced iron, raw material gas 27 enters heating device 28 through reducing gas inlet pipe 87, and after being heated to about 980℃ in heating device 28, it is injected into vertical furnace 4 through outlet pipe 88 from vertical furnace reducing gas inlet 22 below vertical furnace reducing gas inlet 1 41 in gas-based vertical furnace reduction section 2. Raw material gas 6 is injected into vertical furnace 4 from vertical furnace reducing gas inlet 3 43 at the bottom of vertical furnace cooling section 3 without heating. The amount of coal gasification required for raw material gas 6 is about 300M 3 / t·Reduced Iron; Iron oxides added to the vertical shaft furnace 4 from the top charging device 12 run counter-currently with the high-temperature self-produced purified coal gas 13, raw material gas 16, and raw material gas 27. The iron oxides are gradually heated through the upper preheating section 1 and reduction section 2 of the vertical shaft furnace, and react with the high-temperature self-produced purified coal gas 13, raw material gas 27, and raw material gas 16, and are reduced to high-temperature reduced iron. The gas after the reaction of the self-produced purified coal gas 13, raw material gas 27, and raw material gas 16 with the iron oxides passes through the upper preheating section 1 of the vertical shaft furnace and the temperature drops to 350-500℃, forming the self-produced crude coal gas of the vertical shaft furnace. The self-produced crude coal gas enters the vertical shaft furnace gas purification device 10 through the top coal gas pipeline. The high-temperature reduced iron in the reduction section 2 of the vertical shaft furnace continues to enter the cooling section 3 and reacts with the raw material gas injected from the lower part of the cooling section 3. The reaction of raw gas 16 further improves the metallization rate of reduced iron and increases the carburization of reduced iron. Raw gas 16 gradually cools the reduced iron 11, which passes through the lower cooling section 3 of the gas-based vertical shaft furnace and is then discharged from the furnace through the discharge device 5. At the same time, the high-temperature reduced iron heats the raw gas 16. The heated raw gas 16 and the gas after reacting with the high-temperature reduced iron gradually enter the reduction section 2 and the upper preheating section 1 of the vertical shaft furnace to continue to participate in the chemical reaction of the substances in the reduction section 2 and the upper preheating section 1. During the entire reaction process in the vertical shaft furnace, the hydrocarbons in raw gas 16 and raw gas 27 are reformed into reducing gases hydrogen and carbon monoxide under the catalysis of reduced iron, which participate in the reduction reaction of iron oxides. At the same time, components such as ethylene, acetylene, BTX, tar and naphthalene that are prone to carbon deposition are removed.

[0080] The heating process of heating device 9 is the same as in Example 1; the heating and carbon removal process of heating device 8 is the same as in Example 3.

[0081] Using the scheme in this embodiment, the amount of coal gas that needs to be heated separately is only 1750M³ of the total gas volume of the traditional heating method. 3 The reduced iron content of 17% significantly reduces the amount of carbon buildup that may occur when heating coal for gasification. Furthermore, because the two furnaces work alternately, even when cleaning carbon buildup in one furnace, the other furnace continues to heat the raw material gas for the vertical furnace, thus not affecting production.

[0082] Example 5

[0083] Please see Figure 3 , Figure 4 and Figure 8 Coke oven gas is used as feedstock gas one and feedstock gas two. The purified coal gas produced by the vertical shaft furnace and feedstock gas two are heated to 980℃. The purified coal gas produced by the vertical shaft furnace is heated by the high-temperature resistant tube in heating device one, and feedstock gas two is heated by the heat storage body in heating device two. The purified coal gas produced by the vertical shaft furnace and feedstock gas two enter the same reducing gas inlet on the reduction section of the vertical shaft furnace from two pipelines respectively. Heating device two includes three independent heating furnaces, and the following gas-based vertical shaft furnace direct reduction method is adopted:

[0084] Iron oxide particles with a size of 8-16mm are added to the gas-based vertical shaft furnace 4 through the top charging device 12. The raw coal gas produced by the furnace undergoes a series of purification processes (dust removal, dehydration, desulfurization, and carbon dioxide removal) by the gas purification device 10, resulting in purified coal gas 13. This purified coal gas 13 enters the heating device 9 via the reducing gas inlet pipe 94. After being heated to approximately 980℃, it is injected into the vertical shaft furnace 4 through the outlet pipe 95 from the reducing gas inlet 41 of the reduction section 2. The amount of purified coal gas 13 produced by the furnace is approximately 1150 M³. 3 / t·reduced iron, the amount of coke oven gas required for raw material gas 27 is approximately 200M 3 / t·reduced iron, raw material gas 27 enters heating device 28 through reducing gas inlet pipe 87, and is heated to about 980℃ by heating device 28. After being discharged through outlet pipe 88, it is injected into vertical furnace 4 from vertical furnace reducing gas inlet 41 of gas-based vertical furnace reduction section 2. Raw material gas 6 is injected into vertical furnace 4 from vertical furnace reducing gas inlet 3 43 at the lower part of vertical furnace cooling section 3 without heating. The amount of coke oven gas required for raw material gas 6 is about 200M 3 / t·reduced iron. Iron oxides added to the vertical shaft furnace 4 from the top charging device 12 run counter-currently with the high-temperature self-produced purified coal gas 13, raw material gas one 6, and raw material gas two 7. The iron oxides are gradually heated through the upper preheating section 1 and reduction section 2 of the vertical shaft furnace, and simultaneously react with the high-temperature self-produced purified coal gas 13, raw material gas two 7, and raw material gas one 6, being reduced to high-temperature reduced iron. The gas produced after the reaction of the self-produced purified coal gas 13, raw material gas two 7, and raw material gas one 6 with the iron oxides is cooled to 350-500℃ after passing through the upper preheating section 1 of the vertical shaft furnace, forming self-produced crude coal gas. This crude coal gas enters the vertical shaft furnace gas purification device 10 through the top coal gas pipeline; the reduction section 2 of the vertical shaft furnace... The high-temperature reduced iron continues to flow downwards into cooling section 3, reacting with raw material gas 6 injected from the lower part of cooling section 3 of the vertical shaft furnace. This further increases the metallization rate and carburization of the reduced iron. Raw material gas 6 gradually cools the reduced iron 11, which is then discharged from the furnace through the lower cooling section 3 of the gas-based vertical shaft furnace. Simultaneously, the high-temperature reduced iron heats the raw material gas 6. The heated raw material gas 6 and the gas produced after its reaction with the high-temperature reduced iron gradually enter the reduction section 2 and the upper preheating section 1 of the vertical shaft furnace to continue participating in the chemical reactions of the substances within these sections. Throughout the entire reaction process within the vertical shaft furnace, the hydrocarbons in raw material gas 6 and raw material gas 7 are reformed into reducing gases hydrogen and carbon monoxide under the catalytic action of the reduced iron, participating in the reduction reaction of iron oxides. At the same time, components that easily accumulate carbon, such as ethylene, acetylene, BTX, tar, and naphthalene, are removed.

[0085] The heating process of heating device 19 is the same as that in Example 3, and the heating process and carbon removal process of heating device 28 are the same as those in Example 1.

[0086] Using the scheme in this embodiment, the amount of coke oven gas that needs to be heated separately is only 1750M³ of the total gas volume of the traditional heating method. 3 The reduced iron content of 12% significantly reduces the amount of carbon deposits that may be generated from heating coke oven gas. At the same time, since the three furnaces work alternately, while cleaning the carbon deposits in one furnace, the other two furnaces continue to heat the raw material gas for the vertical furnace, thus not affecting production.

[0087] Finally, it should be noted that the above-listed embodiments are merely preferred embodiments of the present invention. Of course, those skilled in the art can make modifications and variations to the present invention. If such modifications and variations fall within the scope of the claims of the present invention and their equivalents, they should be considered as being within the protection scope of the present invention.

Claims

1. A method for direct reduction in a gas-based vertical shaft furnace, comprising: adding iron oxides of a certain particle size into the gas-based vertical shaft furnace from the top charging device; purifying the crude coal gas generated by the vertical shaft furnace itself into purified coal gas; heating the purified coal gas and the raw material gas produced by the vertical shaft furnace; injecting the purified coal gas and the raw material gas into the gas-based vertical shaft furnace from outside; and reducing the iron oxides to direct reduced iron by reacting with the raw material gas and the purified coal gas produced by the vertical shaft furnace, which is then discharged from the furnace after passing through the lower cooling section of the gas-based vertical shaft furnace, characterized in that: The purified coal gas produced by the vertical shaft furnace is heated by a heating device and then injected into the vertical shaft furnace from the reduction section of the gas-based vertical shaft furnace. The raw material gas is injected into the vertical furnace from the lower part of the cooling section. After being heated by heating device 2, the second raw material gas is injected into the vertical furnace from the reduction section of the gas-based vertical furnace. Heating device 2 includes at least two independent heating furnaces, so that when one furnace is treating carbon deposits, the other furnace can still heat the second raw material gas. Using coke oven gas as feedstock gas one and feedstock gas two, when the vertical shaft furnace produces 1150 M³ of purified gas... 3 When reducing iron by / t, the amount of coke oven gas required for raw material gas 2 is 180M. 3 / t·reduced iron, the required coke oven gas volume is 220M³. 3 / t·reduced iron; Alternatively, coke oven gas can be used as feedstock gas one and feedstock gas two, when the vertical shaft furnace produces 1150 M³ of purified gas. 3 When reducing iron, the amount of coke oven gas required for raw material gas 2 is 160M. 3 / t·reduced iron, the required coke oven gas volume is 240M³. 3 / t·reduced iron; Alternatively, coal gasification can be used as both feedstock gas one and feedstock gas two, when the vertical shaft furnace produces 1150 M³ of purified coal gas. 3 When reducing iron, the amount of coal gasification required for feedstock gas 2 is 250M. 3 / t·reduced iron, the required coal gasification volume for raw material gas is 350M. 3 / t·reduced iron; Alternatively, coke oven gas can be used as feedstock gas one and feedstock gas two, when the vertical shaft furnace produces 1150 M³ of purified gas. 3 When reducing iron, the amount of coke oven gas required for raw material gas 2 is 200M. 3 / t·reduced iron, the required amount of coke oven gas is 200M 3 / t·reduced iron; When the heated purified coal gas produced by the vertical shaft furnace and the second raw material gas enter the same reducing gas inlet on the reduction section of the vertical shaft furnace from two pipelines respectively, the pipeline carrying the hot raw material gas enters from the side of the pipeline carrying the hot purified coal gas of the vertical shaft furnace and extends out from the pipe opening. Each independent heating furnace in heating device two has a reducing gas inlet pipe connected to a gas pipeline for cleaning carbon deposits, and a reducing gas outlet pipe connected to a pipeline for discharging waste gas generated during the cleaning of carbon deposits. Carbon deposits are cleaned by filling the gas pipeline for cleaning carbon deposits with high-temperature steam and / or air. The crude gas produced by the vertical shaft furnace, after reacting with iron oxides in the vertical shaft furnace with the self-produced purified coal gas, raw material gas one and raw material gas two, enters the coal gas purification device at the top of the vertical shaft furnace.

2. The direct reduction method for a gas-based vertical shaft furnace according to claim 1, characterized in that: The purified coal gas and raw material gas II produced by the vertical shaft furnace are heated by heating device I and heating device II respectively, and then enter the reduction section of the vertical shaft furnace in any of the following ways: (1) The heated vertical furnace self-produced purified coal gas and raw material gas II enter the vertical furnace from different reducing gas inlets on the reduction section of the gas-based vertical furnace. The inlet of the vertical furnace self-produced purified coal gas on the vertical furnace is located above the inlet of raw material gas II. (2) The heated vertical furnace self-produced purified coal gas and raw material gas II enter the vertical furnace from different reducing gas inlets on the reduction section of the gas-based vertical furnace. The inlet of the vertical furnace self-produced purified coal gas on the vertical furnace is located below the inlet of raw material gas II. (3) The purified coal gas produced by the heated vertical furnace and the raw material gas are mixed and then enter the reducing gas inlet of the reduction section of the vertical furnace; (4) The heated vertical furnace produces purified coal gas and raw material gas, which enter each reducing gas inlet on the reduction section of the vertical furnace through two pipelines respectively.

3. The direct reduction method for a gas-based vertical shaft furnace according to claim 1 or 2, characterized in that: The temperature at which the self-produced purified coal gas and raw material gas 2 enter the vertical shaft furnace is 900-1050℃, and the temperature at which the self-produced purified coal gas enters the vertical shaft furnace is less than or equal to the temperature at which the raw material gas 2 enters the vertical shaft furnace.

4. The direct reduction method for a gas-based vertical shaft furnace according to claim 1, characterized in that: All the crude gas produced by the vertical shaft furnace is purified into purified gas, which is then recycled within the furnace itself.

5. The direct reduction method for a gas-based vertical shaft furnace according to claim 1, characterized in that: Both the heating device one for heating the purified coal gas produced by the vertical furnace and the heating device two for heating the raw material gas adopt regenerative heating technology.

6. The direct reduction method for a gas-based vertical shaft furnace according to claim 5, characterized in that: The heating method for the purified coal gas and raw material gas No. 2 produced by the vertical shaft furnace shall be one of the following: (1) The purified coal gas and raw material gas produced by the vertical furnace are heated by the heat storage body in the heat storage heating device 1 and the heat storage heating device 2, respectively; (2) The purified coal gas and raw material gas II produced by the vertical furnace are heated by the high-temperature resistant tubes in the regenerative heating device I and the regenerative heating device II, respectively. The heat storage body in the regenerative heating device I and the regenerative heating device II is used to heat the air. The high-temperature resistant tube in the combustion chamber is heated by the combustion of air and fuel gas. The high-temperature resistant tube is filled with purified coal gas or raw material gas II produced by the vertical furnace. (3) The purified coal gas produced by the vertical furnace is heated by the heat storage body in the first heat storage heating device, and the raw material gas is heated by the high temperature resistant tube in the second heat storage heating device. (4) The purified coal gas produced by the vertical furnace is heated by the high-temperature resistant tube in the first heat storage heating device, and the raw material gas is heated by the heat storage body in the second heat storage heating device.

7. The direct reduction method for a gas-based vertical shaft furnace according to claim 6, characterized in that: When the purified coal gas or raw material gas produced by the vertical shaft furnace is heated by the heat storage body, either heat storage heating device 1 or heat storage heating device 2 includes three independent heat storage heating furnaces; when the purified coal gas or raw material gas produced by the vertical shaft furnace is heated by the high temperature resistant tube, either heat storage heating device 1 or heat storage heating device 2 includes two independent heat storage heating furnaces.

8. A direct reduction method for a gas-based vertical shaft furnace according to claim 6 or 7, characterized in that: When the second raw material gas is directly heated by the heat storage body, the heat storage body can be removed, the carbon deposits on the heat storage body material can be cleaned, and then it can be put back into the second heat storage heating device for reuse.

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