Method for producing hydrogen through catalytic gasification of oily sludge

Abstract

The invention discloses a method for producing hydrogen by catalytic gasification of oil-containing sludge, which comprises the following steps: directly feeding the oil-containing sludge into a fixed bed gasifier, pyrolyzing and cracking at the high temperature of 700-900 DEG C to generate hydrogen, methane and carbon oxides, and simultaneously generating solid carbon residues, arranging a catalytic wall compounded by 50% titanium-nickel alloy and 50% aluminum oxide in the gasifier, hydrogen release is promoted at high temperature, coke accumulation is reduced, the gasification efficiency is improved, airflow control is oriented, a high-temperature corrosion-resistant airflow guide plate with an adjustable angle is arranged in the gasification furnace, a gas flowing path is optimized, and the hydrogen yield is improved. Therefore, the solid oxide fuel cell and the tail gas recovery system achieve energy self-circulation and tail gas cracking, the overall energy utilization efficiency is improved, meanwhile, pollution of harmful organic matter is reduced through a TiO photocatalytic degradation system, the environmental protection property is improved, and compared with the background technology, the solid oxide fuel cell and the tail gas recovery system have the advantages of being simple in structure and convenient to use. The problems of low energy efficiency, poor hydrogen purity, high carbon emission and difficulty in byproduct treatment in the traditional technology are solved.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen production, and in particular to a method for producing hydrogen by catalytic gasification of oily sludge. Background Art

[0002] Oily sludge is a highly polluting solid waste derived from oil extraction, refining and related industrial processes. It contains a large amount of organic matter, heavy metals and difficult-to-degrade pollutants. Traditional treatment methods include incineration, landfill, solvent extraction and biodegradation. Although incineration can effectively reduce the volume, it has high energy consumption and is prone to produce harmful gases such as dioxins. Landfilling is prone to soil and groundwater pollution. After solvent extraction and oil recovery, the remaining sludge still needs to be treated, and biodegradation has low efficiency and a long cycle. In recent years, pyrolysis gasification technology has gradually become an important way to treat oily sludge. It decomposes organic components at high temperatures to produce combustible gases, of which hydrogen is a high value-added product. However, conventional catalysts are easily covered by coke, resulting in decreased activity and affecting hydrogen yield. Secondly, during the gasification reaction, the gas flow is unevenly distributed, resulting in excessively high or low temperatures in some areas, affecting reaction stability. In addition, existing hydrogen separation methods rely on condensation, adsorption or membrane separation, which have high energy consumption and limited separation efficiency, and cannot guarantee the efficient extraction of high-purity hydrogen. On the other hand, by-products (such as tar, CO and CH 4 ) are difficult to utilize effectively, and some technical solutions fail to fully recycle energy, resulting in low overall energy efficiency of the system and a greater risk of environmental pollution. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, the purpose of the present invention is to propose a method for producing hydrogen by catalytic gasification of oily sludge, which reduces coke accumulation and improves hydrogen release efficiency by using a titanium-nickel alloy and alumina composite catalytic wall, and combines plasma enhanced cracking and supercritical CO 2 Fluid extraction technology enables efficient and low-energy hydrogen extraction, while optimizing the gas flow guide system to ensure uniform gasification reaction, improve hydrogen purity and yield, reduce by-product pollution, and improve energy utilization through solid oxide fuel cells (SOFC) and tail gas recovery and cracking systems, achieving a more environmentally friendly and efficient oily sludge gasification hydrogen production process.

[0005] To achieve the above object, the present invention proposes a method for producing hydrogen by catalytic gasification of oily sludge, comprising the following steps: S1, sludge gasification, the oily sludge is directly sent to the fixed bed gasifier, pyrolyzed at a high temperature of 700°C to 900°C, cracked to produce hydrogen, methane and carbon oxides, and solid carbon slag; S2, catalytic assisted decomposition, a catalytic wall composed of 50% titanium-nickel alloy and 50% alumina is set in the gasifier to promote hydrogen release at high temperature, reduce coke accumulation and improve gasification efficiency; S3, directional airflow control, the gasifier is equipped with an adjustable angle high-temperature corrosion-resistant airflow guide plate to optimize the gas flow path and increase the hydrogen yield; S4, plasma enhanced cracking, with a peripheral configuration of a 2.45GHz microwave plasma source with a power of 200W to 500W, which promotes the cracking of hydrocarbons through the electron bombardment effect and improves the hydrogen yield; S5, supercritical gas separation, using supercritical CO 2 Fluid extraction, separating hydrogen at a pressure of 30MPa to 50MPa with a purity of more than 85%, without the need for traditional condensation and fractionation equipment; S6, carbon slag electricity conversion, solid oxide fuel cell treatment of carbon slag, power generation efficiency of more than 80%, the electricity is used for gasification process, realizing energy self-circulation; S7, photocatalytic degradation of byproducts, using TiO 2 Photocatalytic oxidation uses 250nm to 365nm ultraviolet light to degrade trace harmful organic matter and reduce pollution; S8, tail gas recycling, the tail gas after supercritical separation is returned to the gasifier, cracked by an alumina-based catalyst at 650°C to 750°C, to increase the hydrogen yield and reduce carbon emissions.

[0006] The method for producing hydrogen by catalytic gasification of oily sludge of the present invention adopts catalytic assisted decomposition, microwave plasma enhanced cracking, supercritical CO 2 Innovative technologies such as gas separation have optimized the gasification process of oily sludge, increased the yield and purity of hydrogen, and effectively reduced the generation of by-products. Solid oxide fuel cells and tail gas recovery systems have achieved energy self-circulation and tail gas cracking, improving the overall energy utilization efficiency. 2 The photocatalytic degradation system reduces pollution from harmful organic matter and improves environmental protection. Compared with the background technology, it solves the problems of low energy efficiency, poor hydrogen purity, high carbon emissions and difficult by-product treatment in traditional technologies.

[0007] In addition, the method for producing hydrogen by catalytic gasification of oily sludge according to the present invention may also have the following additional technical features: Specifically, the catalytic wall is made of titanium-nickel alloy and alumina composite material, the thickness of the catalytic wall is 5mm to 15mm, and a microporous structure is provided on the surface of the catalytic wall, which can enhance the heat conduction efficiency of the gasification reaction zone, promote hydrogen release under high temperature environment, reduce coke deposition, and improve gasification efficiency.

[0008] Specifically, the airflow guide plate is made of high-temperature resistant alloy with a thickness of 2mm to 5mm. A guide groove structure is provided on the surface. The guide angle is adjustable within the range of 0° to 45°. The gas flow direction is dynamically adjusted through the pneumatic control system to improve the uniformity of the gasification reaction, optimize the distribution of hydrogen and carbon oxides, and increase the hydrogen yield.

[0009] Specifically, the microwave plasma source uses a frequency of 2.45GHz and a power range of 200W to 500W. The discharge area is equipped with a high-density electromagnetic shielding layer to reduce energy loss and ensure stable operation of the plasma. It also enhances the cracking of hydrocarbons through the electron bombardment effect and increases the hydrogen release rate.

[0010] Specifically, supercritical CO 2 The fluid extraction system adopts a two-stage pressure control method. The working pressure of the first stage is 30MPa to 40MPa, which is used for the preliminary separation of hydrogen and methane. The working pressure of the second stage is 40MPa to 50MPa, which is used for high-purity hydrogen extraction. It uses a high-pressure resistant stainless steel separation chamber to ensure the stability of the separation process and avoid carbon deposition under high-pressure environment.

[0011] Specifically, the solid oxide fuel cell adopts a double-layer composite electrolyte structure composed of yttrium-stabilized zirconia and magnesium-doped alumina. The fuel electrode material is nickel-titanium alloy. The battery operating temperature is 800°C to 1000°C and has a power generation efficiency of more than 80%. The output electrical energy is used to maintain the operation of the plasma enhanced cracking device, realizing the internal recycling of energy.

[0012] Specifically, the photocatalytic degradation system uses TiO 2 The photocatalyst is loaded on a high-porosity diatomaceous earth substrate. The photocatalyst loading is 50mg / m², the UV light source wavelength range is 250nm to 365nm, and the light intensity is 100mW / cm², ensuring that the gasification by-products are degraded into harmless gases during the photocatalytic process, thereby improving the environmental performance of the system.

[0013] Specifically, the tail gas recovery system uses a multi-stage cracking catalytic device to return the tail gas after supercritical separation to the gasifier, and uses an aluminum oxide-nickel composite catalyst to crack CO and CH at a temperature range of 650°C to 750°C. 4 , improve hydrogen conversion efficiency, reduce carbon emissions, and increase hydrogen yield.

[0014] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 This is a schematic diagram of the method for producing hydrogen by catalytic gasification of oily sludge according to the present invention; Figure 2 This is a schematic diagram of experimental data comparing the present invention with conventional hydrogen separation technology; Figure 3 It is a schematic diagram of experimental data of an experiment of treating oily sludge with a fixed bed gasifier of the present invention; Figure 4 It is a schematic diagram of experimental data of the plasma enhanced cracking experiment of the present invention; Figure 5 It is a schematic diagram of experimental data of the photocatalytic degradation experiment of byproducts of the present invention; Figure 6 The supercritical CO 2 Schematic diagram of experimental data of gas separation experiment; Figure 7 It is a schematic diagram of experimental data of the tail gas recovery and utilization experiment of the present invention. DETAILED DESCRIPTION

[0016] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limitations of the present invention. On the contrary, embodiments of the present invention include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0017] The method for producing hydrogen by catalytic gasification of oily sludge according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0018] like Figure 1-Figure 7 As shown, the method for producing hydrogen by catalytic gasification of oily sludge according to the embodiment of the present invention may include the following steps: S1. Sludge gasification: The oily sludge is directly sent into a fixed bed gasifier, where it is pyrolyzed at a high temperature of 700°C to 900°C to generate hydrogen, methane and carbon oxides, and solid carbon slag.

[0019] It should be noted that in the sludge gasification process described in this embodiment, the oily sludge does not need additional pretreatment and directly enters the fixed bed gasifier, and the organic components are converted into hydrogen, methane and carbon oxides through thermal cracking and partial oxidation reactions at a high temperature of 700° C. to 900° C. At the same time, the furnace is provided with a high-temperature corrosion-resistant lining material (such as an alumina-zirconium composite material), which can effectively improve the thermal stability and reduce the coking phenomenon, making the gasification process more stable, and the carbon slag discharge uniform, ensuring the efficient subsequent energy recovery and by-product treatment.

[0020] S2. Catalytic assisted decomposition. A catalytic wall composed of 50% titanium-nickel alloy and 50% alumina is set in the gasifier to promote hydrogen release at high temperature, reduce coke accumulation and improve gasification efficiency.

[0021] It should be noted that in the catalytic assisted decomposition process described in this embodiment, the catalytic wall in the gasifier is made of 50% titanium-nickel alloy and 50% alumina composite material, and its surface is provided with a nano-scale microporous structure (pore size 0.1-0.5mm), which can improve the heat conduction efficiency and provide additional active sites, promote the cracking of organic molecules, and increase the hydrogen release rate. In addition, the catalytic wall has anti-coking performance in a high temperature environment, and by regulating the temperature distribution in the furnace, carbon deposition is reduced, and long-term stable operation is maintained, while effectively reducing the corrosion of coke on the gasifier wall and improving the service life of the equipment.

[0022] S3. Directional airflow control: the gasifier is equipped with a high-temperature, corrosion-resistant airflow guide plate with an adjustable angle to optimize the gas flow path and increase the hydrogen yield.

[0023] It should be noted that in the directional airflow control process described in this embodiment, a multi-stage high-temperature corrosion-resistant airflow guide plate (made of nickel-chromium alloy or heat-resistant ceramic coating alloy) with adjustable angles is arranged in the gasifier, which can accurately adjust the gas flow direction within the range of 0° to 45° to ensure uniform gas flow in the reaction area and avoid local overheating or cooling effects. In addition, the surface of the guide plate is provided with a spiral guide groove, which can enhance the turbulent mixing effect of the gas, increase the gas-solid contact area of ​​the organic molecules, and increase the gasification reaction rate, thereby increasing the yield of hydrogen and optimizing the distribution of carbon oxides.

[0024] S4, plasma enhanced cracking, with a peripheral 2.45GHz microwave plasma source and a power of 200W to 500W, promotes the cracking of hydrocarbons through the electron bombardment effect and improves the hydrogen yield.

[0025] It should be noted that in the plasma enhanced cracking process described in this embodiment, the peripherally configured 2.45GHz microwave plasma source (power 200W to 500W) excites high-energy electrons through a pulse mode, enhances the molecular bond breaking rate of hydrocarbons, and makes hydrogen release more efficient. At the same time, the discharge area of ​​the plasma source adopts a high-density electromagnetic shielding layer to ensure that the energy is concentrated in the reaction area, reduce energy loss, and combine with inert gas (such as argon) to assist in excitation, improve the stability of the plasma, further optimize the cracking environment in the gasifier, increase the hydrogen yield and reduce the generation of tar by-products.

[0026] S5, supercritical gas separation, using supercritical CO 2Fluid extraction separates hydrogen at a pressure of 30MPa to 50MPa with a purity of over 85% without the need for traditional condensation and fractionation equipment.

[0027] It should be noted that in the supercritical gas separation process described in this embodiment, supercritical CO at a pressure of 30 MPa to 50 MPa is used. 2 Fluid extraction technology that selectively dissolves CO and CH using a controlled temperature (35°C to 60°C) and pressure gradient 4 Impurity gases such as methane and carbon dioxide can be removed, while hydrogen can be separated efficiently due to its low solubility, improving purification efficiency. In addition, the separation system adopts a two-stage expansion separation strategy. In the first stage, methane and carbon oxides are initially removed at 40MPa, and in the second stage, hydrogen is further purified at 50MPa. The final hydrogen purity reaches more than 85%, without the need for condensation, membrane separation or adsorption tower, improving separation efficiency and reducing energy consumption.

[0028] Specifically, supercritical CO 2 Key features of extraction Adjustable solubility, by changing the pressure (usually 30MPa60°C), CO 2 It has strong selectivity in its ability to dissolve different gases or solid substances.

[0029] No pollution, no residue, CO 2 It recovers to gas under normal pressure and does not leave any solvent residue in the product, so it is more environmentally friendly than traditional solvent extraction.

[0030] Low temperature operation reduces thermal degradation due to CO 2 The supercritical point temperature is low, which avoids the degradation of target substances (such as hydrogen, methane, etc.) by high temperature and is suitable for the separation of temperature-sensitive substances.

[0031] Efficient separation and recovery, supercritical CO 2 The extraction process can efficiently separate different gas components and can be recycled and reused to improve energy utilization.

[0032] Supercritical CO 2 Application of extraction in this patent scheme In the process of hydrogen production by catalytic gasification of oily sludge, the mixed gas (H 2 , CO, CH 4 Traditional hydrogen separation methods such as condensation, adsorption separation, and membrane separation have the problems of high energy consumption, low efficiency, or complex equipment. 2 Extraction provides a novel and efficient separation method.

[0033] Working principle: The mixed gas (H2 , CO, CH 4 etc.) into supercritical CO 2 Fluid extraction device.

[0034] In the pressure range of 30MPa~50MPa, CO 2 Entering the supercritical state, selectively dissolving CO and CH 4 etc., while hydrogen (H 2 ) is insoluble in supercritical CO 2 , so it is separated out with a purity of more than 85%.

[0035] Subsequently, CO 2 Reduce pressure and recover to release the extracted CO and CH 4 Gases such as effluent gas can be used for combustion or returned to the gasification system.

[0036] Technical advantages: Avoid high energy consumption problems in condensation and adsorption separation and reduce energy loss during the separation process.

[0037] The separation efficiency is high, and higher purity hydrogen (>85%) can be obtained.

[0038] No chemical solvents are required, solvent pollution is avoided, and environmental protection requirements are met.

[0039] CO recovery 2 Repeated use can further improve system energy efficiency.

[0040] Compared with traditional hydrogen separation technologies (such as Figure 2 shown) It should be understood that supercritical CO 2 Extraction technology utilizes CO 2 The selective dissolution characteristics under high pressure supercritical state can efficiently separate hydrogen, avoiding the high energy consumption and solvent pollution of traditional methods. In the scheme of the present invention, 30MPa~50MPa supercritical CO 2 Hydrogen extraction can increase the purity of hydrogen to more than 85%, while improving system energy efficiency and reducing carbon emissions, which has significant industrial application value.

[0041] S6, carbon slag electricity conversion, solid oxide fuel cell to treat carbon slag, power generation efficiency of more than 80%, electricity is used for gasification process, to achieve energy self-circulation.

[0042] It should be noted that in the carbon slag electric energy conversion process described in this embodiment, a solid oxide fuel cell (SOFC) is used to treat the solid carbon slag generated during the gasification process, and the high carbon content of the carbon slag is used as a fuel source, and the composite structure of the electrolyte and electrode materials (such as yttrium-stabilized zirconia-magnesium-doped alumina) is used to efficiently convert it into electric energy at a high temperature of 800°C to 1000°C. The power generation efficiency of this process exceeds 80%, and the generated electric energy is not only used to operate the plasma excitation device in the gasifier, but also used to maintain other energy requirements of the gasification system, realizing the self-circulation and maximum utilization of energy in the system, effectively reducing external energy requirements and reducing overall operating costs.

[0043] S7, photocatalytic degradation of byproducts, using TiO 2 Photocatalytic oxidation uses 250nm to 365nm ultraviolet light to degrade trace harmful organic matter and reduce pollution.

[0044] It should be noted that in the photocatalytic degradation process of byproducts described in this embodiment, TiO 2 The photocatalyst is combined with a UV light source with a wavelength of 250nm to 365nm to activate TiO through photocatalysis. 2 The electron-hole pairs on the surface effectively degrade the trace organic pollutants produced during the gasification process. The photocatalytic reaction area of ​​the system is equipped with high-efficiency reflectors and light guides to ensure that the ultraviolet light is evenly irradiated to the TiO 2 The catalyst surface significantly improves the degradation efficiency, while converting by-products into harmless gases or stable compounds, reducing pollution and optimizing the environmental performance of the system.

[0045] S8, tail gas recycling, the tail gas after supercritical separation is returned to the gasifier, cracked by an alumina-based catalyst at 650°C to 750°C, to increase the hydrogen yield and reduce carbon emissions.

[0046] It should be noted that in the tail gas recovery process described in this embodiment, supercritical CO 2 The separated tail gas (mainly containing CO, CH 4 The alumina-based catalyst (such as alumina-molybdenum composite catalyst) is used to carry out cracking reaction at a temperature range of 650°C to 750°C. In this process, the alumina-based catalyst not only promotes the 4 Highly efficient conversion into hydrogen, also effectively reducing CO 2 The generation of hydrogen can increase the yield of hydrogen and reduce carbon emissions through catalytic cracking reactions, ensuring that the gasification process is cleaner and more efficient.

[0047] The following is a detailed data description combined with the experimental steps: Example 1 Experimental Study on Treatment of Oily Sludge by Fixed-Bed Gasifier Experimental steps: Raw material preparation: Select oily sludge as raw material and send it directly into the fixed bed gasifier with a water content not exceeding 20%.

[0048] Gasification process: The temperature range in the gasifier was set at 750°C to 850°C. During the gasification process, the fixed bed was directly heated without pre-treatment of the sludge. The reaction time was 4 hours.

[0049] Catalytic Assistance: The inner wall of the gasifier uses a catalytic wall made of 50% titanium-nickel alloy and 50% alumina composite material to improve hydrogen release efficiency and reduce coke accumulation.

[0050] Tail gas recovery: through supercritical CO 2 The fluid extraction system separates the generated hydrogen from other gases to ensure that the hydrogen purity reaches more than 85%.

[0051] Carbon residue treatment: The carbon residue in the gasifier is converted into electrical energy through a solid oxide fuel cell with a power generation efficiency of 80%.

[0052] Comparison of experimental data (such as Figure 3 shown) Experimental results: In Example 1, the use of titanium-nickel alloy and alumina composite catalyst wall effectively increased the hydrogen production and hydrogen purity, reduced coke accumulation, and significantly improved the efficiency of carbon slag to electricity.

[0053] Example 2 Plasma enhanced cracking experiment Experimental steps: Raw material preparation: Select oily sludge and feed it directly into the gasifier, and the pretreatment temperature is set at 800°C.

[0054] Microwave plasma source setting: A 2.45 GHz microwave plasma source is configured outside the gasifier, and the power range is set to 200 W to 500 W.

[0055] Reaction process: Run in the gasifier for 4 hours, using a plasma source to intensify the cracking reaction of hydrocarbons and maximize hydrogen production.

[0056] Hydrogen collection: using supercritical CO 2 Hydrogen is separated by fluid extraction, with a hydrogen purity of 90%.

[0057] Comparison of experimental data (such as Figure 4 shown) Experimental results: With the assistance of a microwave plasma source, the hydrogen yield and purity are significantly improved, by-products are reduced, and the reaction efficiency is effectively improved.

[0058] Example 3 Photocatalytic degradation experiment of byproducts Experimental steps: Raw material processing: The harmful organic matter produced during the gasification process is used as raw material and sent to the photocatalytic degradation device.

[0059] Photocatalyst configuration: using TiO 2 The photocatalyst is supported on a high porosity diatomaceous earth substrate with a photocatalyst loading of 50 mg / m².

[0060] UV irradiation: Use a UV light source with a wavelength of 250nm to 365nm, a light intensity of 100mW / cm², and an irradiation time of 3 hours.

[0061] By-product treatment: Harmful organic matter is converted into harmless gases through photocatalytic reaction.

[0062] Comparison of experimental data (such as Figure 5 shown) Experimental results: Photocatalytic degradation significantly increases the degradation rate of harmful organic matter, reduces pollution emissions, and improves overall environmental performance.

[0063] Example 4 Supercritical CO 2 Gas separation experiments Experimental steps: Gas separation preparation: The mixed gas (H 2 , CH 4 , CO, etc.) into supercritical CO 2 Fluid extraction device.

[0064] Supercritical CO 2 Extraction: Gas separation is carried out at a pressure of 30MPa to 50MPa, with preliminary separation at 30MPa to 40MPa in the first stage and high-purity hydrogen extraction at 40MPa to 50MPa in the second stage.

[0065] Hydrogen purification: After separation, the purity of hydrogen reaches 85%.

[0066] Comparison of experimental data (such as Figure 6 shown) Experimental results: Supercritical CO 2 Fluid extraction technology improves hydrogen purity and separation efficiency. Compared with traditional condensation separation, hydrogen purity is increased by 15% and efficiency is increased by 15%.

[0067] Embodiment 5 Tail gas recovery experiment Experimental steps: Tail gas reflux: The tail gas (including CO, CH 4 etc.) are returned to the gasifier.

[0068] Catalytic cracking: Using an aluminum oxide-nickel composite catalyst, the cracking reaction is carried out at a temperature of 650°C to 750°C to increase the hydrogen yield.

[0069] Gas collection: The cracked gas passes through a gas separation system to extract hydrogen.

[0070] Comparison of experimental data (such as Figure 7 shown) Experimental results: Tail gas recovery and utilization significantly increased hydrogen yield and reduced carbon emissions through catalytic cracking, showing significant environmental benefits.

[0071] In one embodiment of the present invention, Figure 1-Figure 7 As shown, the catalytic wall is composed of titanium-nickel alloy and alumina composite material, the thickness of the catalytic wall is 5mm to 15mm, and a microporous structure is provided on the surface of the catalytic wall, which can enhance the heat conduction efficiency of the gasification reaction zone, promote hydrogen release under high temperature environment, reduce coke deposition, and improve gasification efficiency.

[0072] It should be noted that the catalyst wall described in this embodiment is made of titanium-nickel alloy and alumina composite material, which has excellent thermal stability and corrosion resistance in high temperature environment, and the thickness is designed to be 5mm to 15mm. Through precise structural design, the surface of the catalyst wall is provided with micropores (aperture range is 0.1mm to 0.5mm), which enhances the distribution of gas flow in the reaction zone and the efficiency of heat conduction. This design can not only effectively improve the hydrogen release rate, but also reduce coke deposition and reduce the catalyst deactivation problem caused by carbon deposition by increasing the contact area between gas and solid, thereby significantly improving the overall efficiency of the gasification reaction.

[0073] In one embodiment of the present invention, Figure 1-Figure 7 As shown, the airflow guide plate is made of high-temperature resistant alloy, with a plate thickness of 2mm to 5mm, and a guide groove structure is provided on the surface. The guide angle is adjustable within the range of 0° to 45°. The gas flow direction is dynamically adjusted through the pneumatic control system to improve the uniformity of the gasification reaction, optimize the distribution of hydrogen and carbon oxides, and improve the hydrogen yield.

[0074] It should be noted that the airflow guide plate described in this embodiment is made of high-temperature resistant alloy material (such as nickel-chromium alloy or titanium alloy), with a thickness of 2mm to 5mm, and has excellent high-temperature corrosion resistance and mechanical strength. The surface is designed with a guide groove structure, which can effectively guide the airflow and reduce airflow resistance. During the gasification process, the guide angle can be adjusted from 0° to 45°. The airflow direction is dynamically adjusted through the pneumatic control system to ensure that the gas flow is more uniform, avoid local overheating or cooling, optimize the temperature distribution of the reaction zone, and thus improve the contact efficiency between hydrogen and carbon oxides, and significantly improve the hydrogen yield and reaction stability.

[0075] In one embodiment of the present invention, Figure 1-Figure 7 As shown, the microwave plasma source adopts a frequency of 2.45GHz and a power range of 200W to 500W. The discharge area is equipped with a high-density electromagnetic shielding layer to reduce energy loss and ensure stable operation of the plasma. It also enhances the cracking of hydrocarbons through the electron bombardment effect and increases the hydrogen release rate.

[0076] It should be noted that the microwave plasma source described in this embodiment uses a frequency of 2.45 GHz, with an adjustable power range of 200 W to 500 W, and has the characteristics of efficient energy conversion and directional energy transmission, ensuring high energy density in the reaction area. In order to improve energy utilization efficiency, the discharge area is equipped with a high-density electromagnetic shielding layer to effectively prevent energy leakage and reduce unnecessary energy loss. At the same time, the molecules in the gas are activated through the electron bombardment effect, promoting the rapid cracking of hydrocarbons, thereby significantly increasing the hydrogen release rate and reducing the generation of by-products, optimizing the gasification process.

[0077] In one embodiment of the present invention, Figure 1-Figure 7 As shown, supercritical CO 2 The fluid extraction system adopts a two-stage pressure control method. The working pressure of the first stage is 30MPa to 40MPa, which is used for the preliminary separation of hydrogen and methane. The working pressure of the second stage is 40MPa to 50MPa, which is used for high-purity hydrogen extraction. It uses a high-pressure resistant stainless steel separation chamber to ensure the stability of the separation process and avoid carbon deposition under high-pressure environment.

[0078] It should be noted that the supercritical CO 2The fluid extraction system adopts a two-stage pressure control method. The working pressure of the first stage is set at 30MPa to 40MPa, which is used to effectively separate hydrogen from light hydrocarbon gases such as methane. In the second stage, high-purity hydrogen is further extracted under high-pressure conditions of 40MPa to 50MPa to ensure that the purity of hydrogen exceeds 85%. The entire process uses a high-pressure stainless steel separation chamber with good mechanical strength and corrosion resistance to ensure stable operation under supercritical conditions. At the same time, by precisely controlling the temperature and pressure of the fluid, carbon deposition that may occur under high-pressure environments is avoided, effectively improving hydrogen separation efficiency and reducing equipment maintenance requirements.

[0079] In one embodiment of the present invention, Figure 1-Figure 7 As shown in the figure, the solid oxide fuel cell adopts a double-layer composite electrolyte structure, which is composed of yttrium-stabilized zirconium oxide and magnesium-doped alumina. The fuel electrode material is nickel-titanium alloy. The battery operating temperature is 800°C to 1000°C, with a power generation efficiency of more than 80%. The output power is used to maintain the operation of the plasma enhanced cracking device to achieve internal recycling of energy. The photocatalytic degradation system uses TiO 2 The photocatalyst is loaded on a high-porosity diatomaceous earth substrate with a loading of 50 mg / m². The wavelength range of the ultraviolet light source is 250 nm to 365 nm, and the illumination intensity is 100 mW / cm², ensuring that the gasification byproducts are degraded into harmless gases during the photocatalytic process, thereby improving the environmental performance of the system. The tail gas recovery system uses a multi-stage cracking catalytic device to return the tail gas after supercritical separation to the gasifier, and uses an aluminum oxide-nickel composite catalyst to crack CO and CH in the temperature range of 650°C to 750°C. 4 , improve hydrogen conversion efficiency, reduce carbon emissions, and increase hydrogen yield.

[0080] It should be noted that the solid oxide fuel cell (SOFC) described in this embodiment adopts a double-layer composite electrolyte structure, in which yttrium-stabilized zirconia (YSZ) and magnesium-doped alumina (MgO-Al 2 O 3 ) combination provides excellent ionic conductivity and thermal stability, and can withstand high temperature working environment (800°C to 1000°C). The fuel electrode material of the battery is nickel-titanium alloy. Its good electrical conductivity and thermal conductivity enable the battery to maintain high efficiency at high temperatures. The power generation efficiency of more than 80% can provide sufficient electricity for the plasma enhanced cracking device in the gasification process, realize efficient energy recycling and reduce external energy demand;

[0081] The photocatalytic degradation system uses TiO 2The photocatalyst is loaded on a diatomaceous earth substrate with high porosity, which provides a larger surface area to enhance the dispersion of the photocatalyst. The photocatalyst loading is 50mg / m², and the light intensity reaches 100mW / cm² under the irradiation of ultraviolet light source with a wavelength range of 250nm to 365nm, ensuring efficient activation of the photocatalyst. The system effectively degrades the harmful organic pollutants generated during the gasification process and converts them into harmless gases, reducing the impact of by-products on the environment and improving the environmental performance of the system, especially for the treatment of volatile organic compounds (VOCs), achieving a degradation efficiency of more than 90%;

[0082] The tail gas recovery system uses a multi-stage cracking catalytic device to 2 The separated tail gas is deeply cracked and returned to the gasifier. At a temperature of 650°C to 750°C, the alumina-nickel composite catalyst promotes the synthesis of CO and CH 4 The cracking reaction converts it into hydrogen and CO 2 The system significantly improves the hydrogen conversion efficiency by precisely controlling the cracking temperature and catalyst combination, while reducing carbon emissions by more than 30%, effectively increasing the hydrogen yield, and ensuring the energy efficiency and environmental friendliness of the gasification process, promoting the sustainable development of the system.

[0083] In summary, the method for producing hydrogen by catalytic gasification of oily sludge in the embodiment of the present invention adopts catalytic assisted decomposition, microwave plasma enhanced cracking, supercritical CO 2 Innovative technologies such as gas separation have optimized the gasification process of oily sludge, increased the yield and purity of hydrogen, and effectively reduced the generation of by-products. Solid oxide fuel cells and tail gas recovery systems have achieved energy self-circulation and tail gas cracking, improving the overall energy utilization efficiency. 2 The photocatalytic degradation system reduces pollution from harmful organic matter and improves environmental protection. Compared with the background technology, it solves the problems of low energy efficiency, poor hydrogen purity, high carbon emissions and difficult by-product treatment in traditional technologies.

[0084] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and deform the above embodiments within the scope of the present invention.

Claims

1. A method for producing hydrogen by catalytic gasification of oily sludge, characterized in that: The following steps are involved: S1, sludge gasification, the oily sludge is directly sent to the fixed bed gasifier, pyrolyzed at a high temperature of 700°C to 900°C, cracked to produce hydrogen, methane and carbon oxides, and solid carbon slag; S2, catalytic assisted decomposition, a catalytic wall composed of 50% titanium-nickel alloy and 50% alumina is set in the gasifier to promote hydrogen release at high temperature, reduce coke accumulation and improve gasification efficiency; S3, directional airflow control, the gasifier is equipped with an adjustable angle high-temperature corrosion-resistant airflow guide plate to optimize the gas flow path and increase the hydrogen yield; S4, plasma enhanced cracking, with a peripheral configuration of a 2.45GHz microwave plasma source with a power of 200W to 500W, which promotes the cracking of hydrocarbons through the electron bombardment effect and improves the hydrogen yield; S5, supercritical gas separation, using supercritical CO2 fluid extraction to separate hydrogen at a pressure of 30MPa to 50MPa, with a purity of more than 85%, without the need for traditional condensation and fractionation equipment; S6, carbon slag electricity conversion, solid oxide fuel cell treatment of carbon slag, power generation efficiency of more than 80%, the electricity is used for gasification process, realizing energy self-circulation; S7, photocatalytic degradation of byproducts, using TiO2 photocatalytic oxidation, using 250nm to 365nm ultraviolet light to degrade trace harmful organic matter and reduce pollution; S8, tail gas recycling, the tail gas after supercritical separation is returned to the gasifier, cracked by an alumina-based catalyst at 650°C to 750°C, to increase the hydrogen yield and reduce carbon emissions.

2. The method for producing hydrogen by catalytic gasification of oily sludge according to claim 1, characterized in that: The catalytic wall is made of titanium-nickel alloy and alumina composite material with a thickness of 5mm to 15mm. The surface of the catalytic wall is provided with a microporous structure, which can enhance the heat conduction efficiency of the gasification reaction zone, promote hydrogen release under high temperature environment, reduce coke deposition and improve gasification efficiency.

3. The method for producing hydrogen by catalytic gasification of oily sludge according to claim 1, characterized in that: The airflow guide plate is made of high-temperature resistant alloy with a thickness of 2mm to 5mm. It is provided with a guide groove structure on the surface. The guide angle is adjustable in the range of 0° to 45°. The gas flow direction is dynamically adjusted through the pneumatic control system to improve the uniformity of the gasification reaction, optimize the distribution of hydrogen and carbon oxides, and increase the hydrogen yield.

4. The method for producing hydrogen by catalytic gasification of oily sludge according to claim 1, characterized in that: The microwave plasma source uses a frequency of 2.45GHz and a power range of 200W to 500W. The discharge area is equipped with a high-density electromagnetic shielding layer to reduce energy loss and ensure stable operation of the plasma. It also enhances the cracking of hydrocarbons through the electron bombardment effect and increases the hydrogen release rate.

5. The method for producing hydrogen by catalytic gasification of oily sludge according to claim 1, characterized in that: The supercritical CO2 fluid extraction system adopts a two-stage pressure control method. The working pressure of the first stage is 30MPa to 40MPa, which is used for the preliminary separation of hydrogen and methane. The working pressure of the second stage is 40MPa to 50MPa, which is used for high-purity hydrogen extraction. It uses a high-pressure resistant stainless steel separation chamber to ensure the stability of the separation process and avoid carbon deposition under high-pressure environment.

6. The method for producing hydrogen by catalytic gasification of oily sludge according to claim 1, characterized in that: Solid oxide fuel cells use a double-layer composite electrolyte structure composed of yttrium-stabilized zirconia and magnesium-doped alumina. The fuel electrode material is nickel-titanium alloy. The battery operating temperature is 800°C to 1000°C and has a power generation efficiency of more than 80%. The output electricity is used to maintain the operation of the plasma enhanced cracking device, realizing the internal recycling of energy.

7. The method for producing hydrogen by catalytic gasification of oily sludge according to claim 1, characterized in that: The photocatalytic degradation system uses TiO2 photocatalyst loaded on a high-porosity diatomaceous earth substrate. The photocatalyst loading is 50mg / m², the UV light source wavelength range is 250nm to 365nm, and the light intensity is 100mW / cm², ensuring that the gasification by-products are degraded into harmless gases during the photocatalytic process, thereby improving the environmental performance of the system.

8. The method for producing hydrogen by catalytic gasification of oily sludge according to claim 1, characterized in that: The tail gas recovery system returns the tail gas after supercritical separation to the gasifier through a multi-stage cracking catalytic device, and uses an alumina-nickel composite catalyst to crack CO and CH4 in the temperature range of 650°C to 750°C, thereby improving hydrogen conversion efficiency, reducing carbon emissions, and increasing hydrogen yield.

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