Device and method for preparing synthesis gas based on carbon dioxide and high-carbon active matter coupled green hydrogen

Abstract

The invention belongs to the technical field of synthesis gas, and provides a device and a method for preparing synthesis gas based on carbon dioxide and high-carbon active matter coupled green hydrogen. The device comprises a combustion converter, a CO2 storing and conveying device, a green hydrogen storing and conveying device, an O2 storing and conveying device, a high-carbon active matter and catalyst metering and feeding device, a CO preliminary dust removal device and a hydrogen-carbon ratio adjusting device. Oxygen-deficient combustion of high-carbon active matters is carried out at the lower half section of the combustion converter to prepare CO, and heat is provided for reaction at the upper half section of the combustion converter; the upper half section of the combustion converter is used for carrying out catalytic reforming conversion reaction on high-carbon active matters and CO2 to produce CO; compared with a technology for preparing methanol by directly adding green hydrogen into CO2, the technology for preparing methanol by using CO2 and high-carbon active matter coupled green hydrogen to produce high-value chemical raw material synthesis gas has the advantages of more obvious economic benefit, omission of a CO2 activation step and low equipment investment.

Description

Technical Field

[0001] This invention relates to the field of syngas technology, and in particular to an apparatus and method for preparing syngas based on the coupling of carbon dioxide with green hydrogen from high-carbon active substances. Background Technology

[0002] Methanol is widely used in the production of chemical products such as formaldehyde, acetic acid, dimethyl ether, methyl tert-butyl ether (MTBE), methyl methacrylate (MMA), olefins, chloromethane, and dimethyl carbonate, and can also be used as a fuel. Methanol is the best carrier of hydrogen in nature, and its production process can absorb a large amount of carbon dioxide. Currently, green hydrogen-to-methanol technologies mainly include green hydrogen coupled with coal-to-methanol technology, green hydrogen coupled with biomass-to-methanol technology, and green hydrogen plus carbon dioxide-to-methanol technology. Although green hydrogen plus carbon dioxide-to-methanol is a very promising renewable energy production method, it still faces many challenges, such as low catalyst efficiency, poor stability, difficult recovery, and the consumption of large amounts of hydrogen and energy. In contrast, the carbon monoxide and hydrogen-to-methanol industry is widely used, with mature catalyst technology and lower reaction energy consumption. By using appropriate systems and methods to convert carbon dioxide into carbon monoxide and then produce methanol, it can both achieve carbon dioxide disposal and provide a new route for methanol production.

[0003] Currently, carbon dioxide is mainly used in the biological, physical, and chemical fields. In the biological field, CO2 is used as a gaseous fertilizer for crops, increasing yields. In the physical field, CO2 is used as a protective gas, fire extinguishing material, and coolant. In the chemical field, CO2 is mainly used to synthesize basic chemicals, organic dyes, and polymer materials. Currently, a research hotspot in CO2 conversion applications is the CO2 and methane reforming technology to produce syngas (CO+H2), which can reduce CO2 and methane emissions, and the generated syngas can be used as a raw material for synthesizing alcohols and ethers. However, the bottleneck limiting the widespread application of CO2 and methane reforming technology is the lack of low-cost, highly active catalysts with strong anti-carbon deposition properties. The CO2 and methane reforming reaction formula is: CH4 + CO2 → 2CO + 2H2, ΔH 298K =247 kJ / mol. Chemical equilibrium and thermodynamic calculations indicate that this reaction is a reversible, strongly endothermic reaction, with high temperature and low pressure favoring the forward reaction. With the rapid development of green electricity and green hydrogen, combining CO2 for resource utilization can quickly restructure the traditional fossil fuel syngas production process. By producing syngas (CO+H2) and then performing subsequent high-value processing or carbon sequestration and emission reduction, low-carbon production can be achieved, reducing carbon emissions in traditional fossil fuel production processes by more than 90%.

[0004] In summary, exploring new pathways for the conversion of carbon dioxide into syngas (CO+H2) and coupling them with green hydrogen applications and utilization, along with mature syngas (CO+H2) to methanol industrial technology, can rapidly realize the conversion and utilization of carbon dioxide resources. Therefore, providing an apparatus and method for the preparation of syngas based on the coupling of carbon dioxide and high-carbon reactive substances with green hydrogen is of great significance. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art by providing an apparatus and method for preparing syngas based on the coupling of carbon dioxide and high carbon active substances with green hydrogen, providing a reliable syngas (CO+H2) feedstock for the industrial technology of producing methanol from green hydrogen and carbon monoxide, and absorbing and utilizing carbon dioxide resources to improve carbon resource and energy utilization efficiency.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] This invention provides an apparatus for preparing syngas based on the coupling of carbon dioxide and high-carbon active substances with green hydrogen. The apparatus includes a combustion conversion furnace, a CO2 storage and conveying device, a green hydrogen storage and conveying device, an O2 storage and conveying device, a high-carbon active substance metering and feeding device, a catalyst metering and feeding device, a CO preliminary dust removal device, and a hydrogen-carbon ratio adjustment device.

[0008] Preferably, the combustion converter is a two-section design, with the lower section configured as an airflow bed and the upper section configured as a fixed bed.

[0009] Preferably, the lower half of the combustion reformer is used for oxygen-deficient combustion of high-carbon active materials to produce CO, providing heat for the reaction in the upper half of the combustion reformer; the upper half of the combustion reformer is used for catalytic reforming of high-carbon active materials and CO2 to produce CO.

[0010] The present invention also provides a method for preparing syngas using the apparatus for preparing syngas based on the coupling of carbon dioxide and high carbon active substances with green hydrogen, comprising the following steps:

[0011] 1) Fossil fuels and oxygen are combusted in the lower half of the combustion converter to increase the temperature and pressure of the combustion converter;

[0012] 2) CO2 gas carrying high-carbon active material is injected into the lower half of the combustion reformer. The reaction gas is also introduced into the lower half of the combustion reformer. The oxygen flow rate is adjusted to ensure that the high-carbon active material is in a combustion state and undergoes oxygen-deficient combustion.

[0013] 3) The gas and CO2 generated by the oxygen-deficient combustion in the lower half of the combustion reformer rise to the upper half of the combustion reformer after fluid spin. The CO2 gas carries high-carbon active material and iron-based catalyst and is injected into the upper half of the combustion reformer. The high-carbon active material and CO2 undergo catalytic reforming reaction to obtain crude CO.

[0014] 4) Hydrogen and crude CO are mixed in a hydrogen-to-carbon ratio regulating device to obtain syngas.

[0015] Preferably, the fossil fuel in step 1) is natural gas or diesel; the temperature of the combustion converter is increased to ≥800°C and the pressure is increased to 1-5 MPa.

[0016] Preferably, the reaction gas in step 2) is a mixture of oxygen and green hydrogen or oxygen; the pressure of the reaction gas is 2.0 MPa, the flow rate of oxygen is 1 to 1.7 L / s, and the flow rate of green hydrogen is 1 to 2.1 L / s.

[0017] The CO2 pressure is 2.0 MPa, the flow rate is 0.6–1.05 L / s, the flow rate of the high-carbon active material is 10–30 g / s, and the particle size is 0.05–0.2 mm.

[0018] Preferably, the oxygen-deficient combustion temperature in step 2) is 900–950°C.

[0019] Preferably, in the upper half of the combustion reformer described in step 3), the flow rate of CO2 gas is 0.3–0.55 L / s, and the pressure is 2.0 MPa; the flow rate of high-carbon active material is 3–12 g / s; and the gas temperature is ≥800℃ during the catalytic reforming reaction.

[0020] Preferably, in step 4), the flow rate of hydrogen is 10–32 L / s and the pressure is 2.0 MPa, and the flow rate of crude CO is 5–16 L / s and the pressure is 2.0 MPa.

[0021] The beneficial effects of this invention include the following:

[0022] 1) This invention uses CO2 and high-carbon active substances coupled with green hydrogen to produce high-value chemical raw material synthesis gas, and then to produce methanol. Compared with the technology of directly adding green hydrogen to CO2 to produce methanol, the economic benefits are more obvious.

[0023] 2) This invention directly generates CO from CO2 with high-carbon active materials, and optimizes the H2 / CO ratio with green hydrogen, eliminating the CO2 activation step and reducing equipment investment. The direct CO2-to-methanol technology is limited by the high activation energy of CO2 and the energy consumption of water vapor separation, resulting in lower conversion efficiency. The overall reaction equation for producing methanol using CO2 with high-carbon active materials and green hydrogen is: 0.5CO2 + 0.5C + 2H2 → CH3OH; the reaction equation for direct CO2-to-methanol hydrogenation is: CO2 + 3H2 → CH3OH + H2O. Theoretical calculations show that, taking the production of 1 ton of methanol as an example, the method of this invention can save 1400 Nm³ of hydrogen compared to direct CO2-to-methanol hydrogenation. 3 Saves 350 Nm³ of carbon dioxide 3 It only consumes an additional 0.19 tons of high-carbon active materials.

[0024] 3) Taking a copper-based catalyst as an example, the single-pass conversion rate of CO2 in the feed gas for CO2 hydrogenation to methanol is only 30%, and the methanol selectivity is 80%. In contrast, the single-pass conversion rate of CO in the feed gas for CO hydrogenation to methanol of the present invention is 70-75%, and the methanol selectivity is over 90%. Therefore, the method of the present invention has higher conversion efficiency and yield for methanol production. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the apparatus for preparing syngas based on the coupling of carbon dioxide and high-carbon active substances with green hydrogen according to the present invention. Detailed Implementation

[0026] This invention provides an apparatus for preparing syngas based on the coupling of carbon dioxide and high-carbon active substances with green hydrogen. The apparatus includes a combustion conversion furnace (reactor), a CO2 storage and conveying device, a green hydrogen storage and conveying device, an O2 storage and conveying device, a high-carbon active substance metering and feeding device, a catalyst metering and feeding device, a CO preliminary dust removal device, and a hydrogen-carbon ratio adjustment device.

[0027] The device of the present invention also includes other protection and test drive devices.

[0028] In this invention, the combustion converter is preferably a two-section design, with the lower section preferably configured as an airflow bed and the upper section preferably configured as a fixed bed.

[0029] In this invention, the lower half of the combustion reformer performs oxygen-deficient combustion of high-carbon active materials to produce CO, providing heat for the reaction in the upper half of the combustion reformer; the upper half of the combustion reformer performs catalytic reforming conversion reaction of high-carbon active materials and CO2 to produce CO.

[0030] A schematic diagram of the apparatus for producing syngas based on the coupling of carbon dioxide and high-carbon active substances with green hydrogen according to the present invention is shown below. Figure 1 As shown, Figure 1 The cyclone separator in the middle is a preliminary CO dust removal device.

[0031] The present invention also provides a method for preparing syngas using the apparatus for preparing syngas based on the coupling of carbon dioxide and high carbon active substances with green hydrogen, comprising the following steps:

[0032] 1) Fossil fuels and oxygen are combusted in the lower half of the combustion converter to increase the temperature and pressure of the combustion converter;

[0033] 2) CO2 gas carrying high-carbon active material is injected into the lower half of the combustion reformer. The reaction gas is also introduced into the lower half of the combustion reformer. The oxygen flow rate is adjusted to ensure that the high-carbon active material is in a combustion state and undergoes oxygen-deficient combustion.

[0034] 3) The gas and CO2 generated by the oxygen-deficient combustion in the lower half of the combustion reformer rise to the upper half of the combustion reformer after fluid spin. The CO2 gas carries high-carbon active material and iron-based catalyst and is injected into the upper half of the combustion reformer. The high-carbon active material and CO2 undergo catalytic reforming reaction to obtain crude CO.

[0035] 4) Hydrogen and crude CO are mixed in a hydrogen-to-carbon ratio regulating device to obtain syngas.

[0036] In this invention, the fossil fuel in step 1) is preferably natural gas or diesel; the temperature of the combustion converter is preferably increased to ≥800℃, more preferably 850~1000℃, more preferably 900~950℃, and the pressure is preferably increased to 1~5MPa, more preferably 2~4MPa, more preferably 3MPa.

[0037] In this invention, the temperature and pressure of the combustion converter are increased by the heat released from the combustion of fossil fuels, thereby establishing a circulation system for the reactants.

[0038] In this invention, the reaction gas in step 2) is preferably a mixture of oxygen and green hydrogen or oxygen; the pressure of the reaction gas is preferably 2.0 MPa, the flow rate of oxygen is preferably 1 to 1.7 L / s, more preferably 1.1 to 1.6 L / s, more preferably 1.2 to 1.5 L / s, and the flow rate of green hydrogen is preferably 1 to 2.1 L / s, more preferably 1.2 to 2.0 L / s, more preferably 1.4 to 1.8 L / s;

[0039] The CO2 pressure is preferably 2.0 MPa, the flow rate is preferably 0.6–1.05 L / s, more preferably 0.625–1.042 L / s, and even more preferably 0.7–1.0 L / s. The flow rate of the high-carbon active material is preferably 10–30 g / s, more preferably 15–25 g / s, and even more preferably 20 g / s. The particle size is preferably 0.05–0.2 mm, and even more preferably 0.08–0.16 mm.

[0040] In this invention, the oxygen-deficient combustion temperature in step 2) is preferably 900-950°C, more preferably 910-940°C, and even more preferably 920-930°C.

[0041] In this invention, the high-carbon active material is preferably coke, petroleum coke, semi-coke, charcoal, or activated carbon. The center temperature of the combustion converter is preferably ≥900℃. Oxygen-deficient combustion is used to ensure the temperature and pressure of the combustion converter. The reaction equation for oxygen-deficient combustion is as follows:

[0042] 2C + O2 → 2CO Q1 (exothermic reaction), 2H2 + O2 = 2H2O Q2 (exothermic reaction).

[0043] In this invention, when the gas in step 2) is a mixture of oxygen and green hydrogen, the oxygen and green hydrogen are first mixed through a nozzle and then burned, and then mixed with high-carbon active material and carbon dioxide in the furnace to continue the oxygen-deficient combustion of high-carbon active material; when the gas is oxygen, oxygen is mixed with high-carbon active material and carbon dioxide at the burner end in the furnace for oxygen-deficient combustion.

[0044] In this invention, the iron-based catalyst in step 3) is preferably an iron-based oxide or iron alloy catalyst, and the mass of the iron-based catalyst is preferably 0.01% to 0.1% of the high carbon active material.

[0045] In this invention, in the upper half of the combustion reformer described in step 3), the flow rate of CO2 gas is preferably 0.3-0.55 L / s, more preferably 0.32-0.52 L / s, and even more preferably 0.35-0.5 L / s, and the pressure is preferably 2.0 MPa; the flow rate of the high-carbon active material is preferably 3-12 g / s, more preferably 5-10 g / s, and even more preferably 6-8 g / s; during the catalytic reforming reaction, the gas temperature is preferably ≥800℃.

[0046] In this invention, CO gas and H2O gas generated from oxygen-deficient combustion, CO2 gas used for conveying and fluidization, and residual high-carbon active materials carrying reaction heat rise from the lower half of the reactor to the upper half after fluid spin. There, they undergo catalytic reforming with replenished fresh CO2 and high-carbon active materials under the action of a continuously replenished iron-based catalyst. The gas temperature in the reactor is above 800°C. The catalytic reforming reaction equation is: C + CO2 → 2CO Q3 (endothermic reaction). The coke in the lower half of the reactor is promptly vented and transported to a high-carbon temporary storage tank. When the reactor level reaches half, fresh CO2 gas carrying high-carbon active materials and iron-based catalyst is injected into the upper half of the combustion conversion furnace. After the catalytic reforming reaction is completed, the unreacted high-carbon active materials enter the high-carbon active material temporary storage tank and are then reintroduced into the upper half of the reactor along with the catalyst for catalytic reforming to produce CO.

[0047] In this invention, the flow rate of hydrogen in step 4) is preferably 10-32 L / s, more preferably 14-28 L / s, and even more preferably 20-24 L / s, and the pressure is preferably 2.0 MPa. The flow rate of crude CO is preferably 5-16 L / s, more preferably 7-14 L / s, and even more preferably 10-12 L / s, and the pressure is preferably 2.0 MPa.

[0048] In this invention, the preferred carbon-to-hydrogen ratio (molar ratio) of the synthesis gas is 2:1.

[0049] The apparatus and method of this invention couple CO2, green hydrogen, and high-carbon reactive materials to produce high-value chemical feedstock syngas (CO+H2), providing suitable feedstock gas for the industrially mature process of carbon monoxide hydrogenation to methanol, and representing a new approach to CO2 resource utilization. This invention utilizes oxygen-deficient combustion of high-carbon reactive materials such as coke, catalytic reforming of active carbon sources with CO2, and improves the production efficiency of syngas (CO+H2) by controlling the amount of CO2 used and coupling it with green hydrogen. It achieves efficient utilization of chemical reaction energy, coupling the exothermic combustion and endothermic reforming processes to ensure efficient CO2 reforming, thus realizing the efficient conversion and utilization of carbon resources.

[0050] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0051] In the embodiment, the combustion conversion furnace (reactor) is 200L, the coke particle size is 0.05-0.2mm, the pressure of CO2, green hydrogen and oxygen is 2.0MPa, and the pressure of crude CO separated by cyclone is 2.0MPa.

[0052] Example 1

[0053] This embodiment first prepares CO by burning coke in an oxygen-deficient environment; secondly, it utilizes the exothermic combustion of coke in an oxygen-deficient environment to promote a catalytic reforming reaction between CO2 and coke to prepare CO; finally, the prepared CO is mixed with green hydrogen to form a gas. The reaction steps are as follows:

[0054] Natural gas and oxygen undergo combustion reaction in the lower half of the reactor. The combustion heat raises the reactor temperature to 850°C and the pressure to 3MPa. The combustion exhaust gas is discharged and treated in a timely manner from the top of the reactor.

[0055] The reactor temperature is maintained at 850℃. CO2 (flow rate 1.042 L / s) carrying coke (flow rate 30 g / s) is injected into the lower half of the reactor, while oxygen enters at a flow rate of 1 L / s. Oxygen, coke, and CO2 mix at the burner tips within the furnace. The coke combustion status is observed using a built-in flame detector, and the oxygen flow rate is adjusted (1–1.67 L / s) to ensure the coke is burning in the lower half of the reactor, forming a clear combustion flame, and the reactor temperature reaches above 900℃.

[0056] Once the reactor temperature stabilizes at 900–950℃, reduce the oxygen flow rate to 1–1.1 L / s, and simultaneously monitor the oxygen content of the gas at the top of the reactor until no oxygen is detected or present in trace amounts. While ensuring stable coke delivery, reduce the CO2 flow rate from 1.042 L / s to 0.625 L / s, and simultaneously monitor the CO2 content of the gas at the top of the reactor, controlling the outlet carbon dioxide volume content to below 10%.

[0057] In the lower half of the reactor, CO2 gas for conveying and fluidizing, along with CO gas generated from oxygen-deficient combustion, carrying unburned high-carbon active materials, forms an internal upward spinning flow field. After the unreacted high-carbon active materials are initially removed by the spinning flow field, the prepared CO and conveying CO2 gas rise from the lower half of the reactor to the upper half. The coke in the lower half of the reactor is emptied regularly and promptly and transported to the high-carbon temporary storage tank. When the material level reaches half, the metering feed device is activated, and coke (flow rate of 10 g / s) and a trace amount of ferroalloy catalyst (catalyst at 0.01% of the coke mass) are carried by CO2 (flow rate of 0.52 L / s) and injected into the fixed bed in the upper half of the reactor. In the upper half, CO2 and high-carbon active materials undergo catalytic reforming to produce CO (the reaction temperature of catalytic reforming is above 800℃).

[0058] After the circulating coke is stably fed to the upper part of the reactor, the CO2 flow rate is reduced from 0.52 L / s to 0.32 L / s, and the CO2 content of the gas at the top of the reactor is monitored simultaneously until the carbon dioxide content in the top gas is undetectable or trace. After the operation stabilizes, the flow rate of crude CO separated by the cyclone is 14 L / s, the CO purity in the gas is above 90%, and the dust content is 0.02 g / L.

[0059] Hydrogen gas (flow rate 28 L / s) from the green hydrogen storage tank is mixed with crude CO (flow rate 14 L / s) separated by cyclone separation in a hydrogen-to-carbon ratio regulating device to prepare synthesis gas with a carbon-to-hydrogen ratio of 2:1, which can be used for subsequent production of chemical products such as methanol.

[0060] Example 2

[0061] This embodiment first prepares CO by burning coke and green hydrogen in an oxygen-deficient environment, generating some water vapor. Second, the exothermic combustion of coke and green hydrogen in an oxygen-deficient environment promotes a catalytic reforming reaction between CO2 and coke to produce CO. Finally, the prepared CO is mixed with green hydrogen to form a gas. The reaction steps are as follows:

[0062] Natural gas and oxygen undergo combustion reaction in the lower half of the reactor. The combustion heat raises the reactor temperature to 800°C and the pressure to 3MPa. The combustion exhaust gas is discharged and treated in a timely manner from the top of the reactor.

[0063] The reactor temperature was maintained at 800℃. CO2 (flow rate 1.042 L / s) carrying coke (flow rate 20 g / s) was injected into the lower half of the reactor. Oxygen and green hydrogen entered the lower half of the reactor at flow rates of 1 L / s and 1.04 L / s, respectively. In the lower half of the reactor, the oxygen and green hydrogen were first mixed through nozzles and then combusted, before mixing with the coke and CO2 inside the furnace to continue the oxygen-deficient combustion of the coke. The combustion state of the coke and green hydrogen was observed using a built-in flame detector. The oxygen flow rate was adjusted (1–1.61 L / s) to ensure that the coke and green hydrogen were in a state of combustion in the lower half of the reactor, forming a clear combustion flame, and the reactor temperature reached above 900℃.

[0064] Once the reactor temperature stabilizes at 900–950℃, reduce the oxygen flow rate to 1–1.1 L / s, and simultaneously monitor the oxygen content of the gas at the top of the reactor until no oxygen is detected or present in trace amounts. While ensuring stable coke delivery, reduce the CO2 flow rate from 1.042 L / s to 0.625 L / s, and simultaneously monitor the CO2 content of the gas at the top of the reactor, controlling the outlet carbon dioxide volume content to below 8%.

[0065] In the lower half of the combustion reformer, CO2 gas for conveying and fluidizing, along with CO and H2O gas generated from oxygen-deficient combustion, carrying unburned high-carbon active materials, forms an internal upward spinning flow field. After the unreacted high-carbon active materials are initially removed by the spinning flow field, the prepared CO and conveying CO2 gas rise from the lower half of the reactor to the upper half. The coke in the lower half of the reactor is emptied regularly and promptly and transported to the high-carbon temporary storage tank. When the material level reaches half, the metering feed device is activated, and coke (flow rate of 6 g / s) and a trace amount of iron-based oxide catalyst (catalyst at 0.1% of the coke mass) are carried by CO2 (flow rate of 0.52 L / s) and injected into the fixed bed in the upper half of the reactor. In the upper half, CO2 and high-carbon active materials undergo catalytic reforming to produce CO (the reaction temperature of catalytic reforming is above 800℃).

[0066] After the circulating coke is stably fed to the upper part of the reactor, the CO2 flow rate is reduced from 0.52 L / s to 0.32 L / s, and the CO2 content of the gas at the top of the reactor is monitored simultaneously until the carbon dioxide content in the top gas is undetectable or trace. After the operation stabilizes, the crude CO flow rate separated by the cyclone separator is 11 L / s, the water vapor flow rate is 15 g / s, and the dust content is 0.02 g / L.

[0067] Hydrogen gas (flow rate 22 L / s) from the green hydrogen storage tank is mixed with crude CO (flow rate 11 L / s) separated by cyclone separation in a hydrogen-to-carbon ratio regulating device to prepare syngas with a carbon-to-hydrogen ratio of 2:1. Water vapor is discharged after condensation, and the syngas can be used for subsequent production of chemical products such as methanol.

[0068] Example 3

[0069] This embodiment first prepares CO by burning coke and green hydrogen in an oxygen-deficient environment, generating some water vapor. Second, the exothermic combustion of coke and green hydrogen in an oxygen-deficient environment promotes a catalytic reforming reaction between CO2 and coke to produce CO. Finally, the prepared CO is mixed with green hydrogen to form a gas. The reaction steps are as follows:

[0070] Diesel fuel and oxygen undergo combustion reaction in the lower half of the reactor. The combustion heat raises the reactor temperature to 900°C and the pressure to 2MPa. The combustion exhaust gas is promptly discharged from the top of the reactor for treatment.

[0071] The reactor temperature was maintained at 900℃. CO2 (flow rate 1.042 L / s) carrying coke (flow rate 10 g / s) was injected into the lower half of the reactor. Oxygen and green hydrogen entered the lower half of the reactor at flow rates of 1.02 L / s and 2.07 L / s, respectively. In the lower half of the reactor, the oxygen and green hydrogen first mixed through nozzles and then burned. The oxygen was almost completely consumed, and the generated water vapor then mixed with the coke and CO2 in the furnace, continuing the oxygen-deficient combustion of the coke. The combustion state of the coke and green hydrogen was observed using a built-in flame detector. The oxygen flow rate was adjusted (1.02–1.62 L / s) to ensure that the coke and green hydrogen were in a state of combustion in the lower half of the reactor, forming a clear combustion flame, and the reactor temperature reached above 900℃.

[0072] Once the reactor temperature stabilizes at 900–950℃, reduce the oxygen flow rate to 1–1.1 L / s, and simultaneously monitor the oxygen content of the gas at the top of the reactor until the oxygen content is undetectable or present in trace amounts. While ensuring stable coke delivery, reduce the CO2 flow rate from 1.042 L / s to 0.625 L / s, and simultaneously monitor the CO2 content of the gas at the top of the reactor, controlling the outlet carbon dioxide volume content to below 6%.

[0073] In the lower half of the combustion reformer, CO2 gas for conveying and fluidizing, along with CO and H2O gas generated from oxygen-deficient combustion, carrying unburned high-carbon active materials, forms an internal upward spinning flow field. After the unreacted high-carbon active materials are initially removed by the spinning flow field, the prepared CO and conveying CO2 gas rise from the lower half of the reactor to the upper half. The coke in the lower half of the reactor is emptied regularly and promptly and transported to the high-carbon temporary storage tank. When the material level reaches half, the metering feed device is activated, and coke (flow rate of 4 g / s) and a trace amount of ferroalloy catalyst (catalyst at 0.05% of the coke mass) are carried by CO2 (flow rate of 0.52 L / s) and injected into the fixed bed in the upper half of the reactor. In the upper half, CO2 and high-carbon active materials undergo catalytic reforming to produce CO (the reaction temperature of catalytic reforming is above 800℃).

[0074] After the circulating coke is stably fed to the upper part of the reactor, the CO2 flow rate is reduced from 0.52 L / s to 0.32 L / s, and the CO2 content of the gas at the top of the reactor is monitored simultaneously until the carbon dioxide content in the top gas is undetectable or trace. After the operation stabilizes, the crude CO flow rate separated by the cyclone separator is 7 L / s, the water vapor flow rate is 30 g / s, and the dust content is 0.02 g / L.

[0075] Hydrogen gas (flow rate 14 L / s) from the green hydrogen storage tank is mixed with crude CO (flow rate 7 L / s) separated by cyclone separation in a hydrogen-to-carbon ratio regulating device to prepare syngas with a carbon-to-hydrogen ratio of 2:1. Water vapor is discharged after condensation, and the syngas can be used for subsequent production of chemical products such as methanol.

[0076] In this invention, oxygen, green hydrogen, and CO2 gas for conveying and fluidizing, carrying high-carbon active materials, are injected at a certain angle into the lower half of the reactor. After ignition by an ignition gun, a combustion reaction occurs. Oxygen and green hydrogen are first mixed through a nozzle and then burned, before being mixed with the high-carbon active materials and CO2 inside the furnace, continuing the oxygen-deficient combustion of the high-carbon active materials. Subsequently, the CO2 gas for conveying and fluidizing, along with the CO and H2O gases generated from the oxygen-deficient combustion, carrying unburned high-carbon active materials, form an internal upward spinning flow field in the lower half of the reactor. After the unreacted high-carbon active materials are initially removed by the spinning flow field, the prepared CO and conveying CO2 gas rise from the lower half of the reactor to the upper half via the spinning flow field. Some of the unreacted high-carbon active materials are intermittently discharged from the bottom of the furnace into a high-carbon active material storage tank, and then conveyed by CO2 to the upper half of the reactor for catalytic reforming. The unreacted high-carbon active material rising from the lower section, along with CO2 for transport, recycled high-carbon active material, and catalyst, undergoes catalytic reforming of CO2 and high-carbon active material in the upper section to produce CO. The CO gas produced in both the upper and lower sections of the reactor is ultimately discharged from the top of the reactor and, after dust removal by a cyclone separator, yields crude CO gas. Green hydrogen is then mixed with the crude CO gas separated by the cyclone separator in a hydrogen-to-carbon ratio regulating device to prepare syngas with a carbon-to-hydrogen ratio of 2:1. This syngas can then undergo purification and refining processes for methanol production. The unreacted high-carbon active material separated by the cyclone separator enters a high-carbon active material storage tank and, along with the added catalyst, enters the catalytic reforming bed in the upper section of the reactor for catalytic reforming to produce CO.

[0077] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An apparatus for preparing syngas based on the coupling of carbon dioxide and high-carbon active substances with green hydrogen, characterized in that, The device includes a combustion conversion furnace, a CO2 storage and conveying device, a green hydrogen storage and conveying device, an O2 storage and conveying device, a high-carbon active substance metering and feeding device, a catalyst metering and feeding device, a CO preliminary dust removal device, and a hydrogen-carbon ratio adjustment device.

2. The apparatus according to claim 1, characterized in that, The combustion converter is a two-section design, with the lower section configured as an airflow bed and the upper section configured as a fixed bed.

3. The apparatus according to claim 1 or 2, characterized in that, The lower half of the combustion reformer produces CO through oxygen-deficient combustion of high-carbon active materials, providing heat for the reaction in the upper half of the combustion reformer; the upper half of the combustion reformer produces CO through catalytic reforming of high-carbon active materials and CO2.

4. The method for preparing syngas using the apparatus for preparing syngas based on the coupling of carbon dioxide and high-carbon active substances with green hydrogen, as described in any one of claims 1 to 3, is characterized in that... It includes the following steps: 1) Fossil fuels and oxygen are combusted in the lower half of the combustion converter to increase the temperature and pressure of the combustion converter; 2) CO2 gas carrying high-carbon active material is injected into the lower half of the combustion reformer. The reaction gas is also introduced into the lower half of the combustion reformer. The oxygen flow rate is adjusted to ensure that the high-carbon active material is in a combustion state and undergoes oxygen-deficient combustion. 3) The gas and CO2 generated by the oxygen-deficient combustion in the lower half of the combustion reformer rise to the upper half of the combustion reformer after fluid spin. The CO2 gas carries high-carbon active material and iron-based catalyst and is injected into the upper half of the combustion reformer. The high-carbon active material and CO2 undergo catalytic reforming reaction to obtain crude CO. 4) Hydrogen and crude CO are mixed in a hydrogen-to-carbon ratio regulating device to obtain syngas.

5. The method according to claim 4, characterized in that, Step 1) The fossil fuel is natural gas or diesel; the temperature of the combustion converter is increased to ≥800℃ and the pressure is increased to 1~5MPa.

6. The method according to claim 4, characterized in that, Step 2) The reaction gas is a mixture of oxygen and green hydrogen or oxygen; the pressure of the reaction gas is 2.0 MPa, the flow rate of oxygen is 1 to 1.7 L / s, and the flow rate of green hydrogen is 1 to 2.1 L / s. The CO2 pressure is 2.0 MPa, the flow rate is 0.6–1.05 L / s, the flow rate of the high-carbon active material is 10–30 g / s, and the particle size is 0.05–0.2 mm.

7. The method according to claim 6, characterized in that, Step 2) The oxygen-deficient combustion temperature is 900-950℃.

8. The method according to claim 6 or 7, characterized in that, In step 3), the flow rate of CO2 gas in the upper section of the combustion reformer is 0.3-0.55 L / s, and the pressure is 2.0 MPa; the flow rate of high-carbon active material is 3-12 g / s; and the gas temperature is ≥800℃ during the catalytic reforming reaction.

9. The method according to claim 8, characterized in that, In step 4), the flow rate of hydrogen is 10–32 L / s and the pressure is 2.0 MPa, while the flow rate of crude CO is 5–16 L / s and the pressure is 2.0 MPa.

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