Process system for producing hydrogen by means of segmented pyrolysis and catalytic gasification of biomass waste

Abstract

The present invention relates to the technical field of biomass gasification hydrogen production, and particularly relates to a process system for producing hydrogen by means of the segmented pyrolysis and catalytic gasification of biomass waste. The hydrogen production rate of a biomass gasification hydrogen production technology is low and makes it difficult to reach 700 mL / g of biomass or above. In order to solve the technical problem, the present invention provides the process system for producing hydrogen by means of the segmented pyrolysis and catalytic gasification of biomass waste. By means of graded and stepwise thermochemical conversion, using cheap aluminum smelting waste residue, pyrolysis semicoke and a carbon molecular sieve as catalysts, and catalyzing tar steam with the pyrolysis residue, the tar yield during the pyrolysis process is significantly reduced, and the hydrogen yield is improved. Catalyzing tar cracking with the aluminum smelting waste residue coupled with the molecular sieve improves the effect of catalyzing tar cracking hydrogen production by means of a cheap nickel-based catalyst. By means of the catalytic reforming of hydrocarbon gases with nickel loaded on the carbon molecular sieve, the hydrogen proportion reaches 70% or above, thereby achieving the purposes of energy conservation and reduction of biomass waste and the harmless resource utilization of aluminum smelting waste residue and pyrolysis residue.

Description

Biomass waste segmented pyrolysis catalytic gasification hydrogen production process system TECHNICAL FIELD

[0001] The present application relates to the technical field of biomass gasification hydrogen production, in particular to a biomass waste segmented pyrolysis catalytic gasification hydrogen production process system. BACKGROUND

[0002] In recent years, hydrogen energy as a clean energy carrier has attracted much attention, and its large-scale preparation technology mainly focuses on fossil fuel cracking reform, water electrolysis and industrial by-product gas purification. At present, about 96% of the global hydrogen production capacity comes from gray hydrogen (direct cracking of fossil fuels) and blue hydrogen (coupling of carbon capture and fossil reforming), but more than 10 kg of CO2 is emitted for every 1 kg of hydrogen produced, which is in sharp contradiction with the low-carbon development goal. Although green hydrogen produced by water electrolysis can achieve zero carbon emissions, its share is only 4%, and it is difficult to quickly achieve large-scale application due to problems such as high cost of noble metal catalysts, electrolytic cell efficiency bottlenecks, and renewable energy power fluctuations.

[0003] Biomass gasification hydrogen production technology has unique advantages due to the renewable nature of its raw materials and carbon cycle characteristics: by gasifying biomass resources such as agricultural and forestry waste, it can theoretically achieve full life cycle carbon balance; if integrated with carbon capture and storage (CCUS) technology, it can also form a negative carbon effect, significantly improving green carbon sink capacity. However, this technology faces the following core bottlenecks:

[0004] Hydrogen-carbon ratio imbalance and selectivity defects

[0005] The inherent hydrogen content of biomass raw materials is low (typical H / C atomic ratio 0.1-0.3), and during the pyrolysis stage, hydrogen elements preferentially participate in water removal and the generation of oxygen-containing volatile matter (such as CO, CH4), resulting in insufficient hydrogen selectivity in the gasification product. Experiments show that the hydrogen yield of conventional fluidized bed gasification is generally less than 60 g / kg of biomass, and the H2 volume concentration in the synthesis gas is usually less than 40%, which is difficult to meet the demand for efficient hydrogen production.

[0006] Tar byproduct restricts system efficiency

[0007] The gasification process is accompanied by the generation of a large amount of polycyclic aromatic hydrocarbon tar (content can reach 20-100 g / Nm 3 ), not only causing energy loss (15-30% of the energy of the raw material), but also easily clogging the pipeline and poisoning the catalyst. Existing purification technologies (such as cyclone dust removal, catalytic cracking) have problems such as high energy consumption and easy deactivation of catalysts, significantly increasing the operating cost of the system.

[0008] Process coupling and energy optimization problems

[0009] Biomass gasification needs to coordinate pyrolysis, reforming, water-gas shift and other multi-stage reactions. The traditional fixed bed / fluidized bed process has insufficient control over the temperature field and gas-solid residence time, resulting in low gasification efficiency (cold coal gas efficiency is usually less than 70%). At the same time, the tar treatment and waste heat recovery system lacks integrated optimization, further restricting the overall energy efficiency improvement.

[0010] Existing improvement schemes focus on catalyst modification (such as nickel-based catalyst doped with rare earth elements) or reactor structure optimization (such as double-bed gasification), which can improve local reaction efficiency, but do not fundamentally solve the systematic problems of low hydrogen selectivity and tar co-control. Therefore, it is urgent to develop new gasification processes and reaction systems to realize the dual breakthrough of biomass hydrogen production efficiency and economy by regulating the gasification medium, strengthening in-situ catalysis and optimizing heat and mass transfer. SUMMARY

[0011] The existing problem in the prior art is that the hydrogen production rate of the biomass gasification hydrogen production technology is low, and it is difficult to reach more than 700 mL / g. In view of the above technical problems, the present application provides a biomass waste segmented pyrolysis catalytic gasification hydrogen production process system, comprising the following steps:

[0012] (1) drying and crushing the biomass waste to below 3 mm;

[0013] (2) continuously adding the crushed biomass waste obtained in step (1) into the gradient pyrolysis device, the material is treated in turn in the baking section, the hot premixing section, the pyrolysis gasification section and the catalytic reforming section under the action of gravity, and semi-coke and volatile matter are obtained, the obtained semi-coke is discharged from the bottom of the gradient pyrolysis device at regular intervals, and the volatile matter is filtered by the accumulated semi-coke in the catalytic conversion section to obtain high-temperature pyrolysis gas;

[0014] (3) continuously introducing the high-temperature pyrolysis gas into the atmospheric catalytic conversion furnace I, so that the tar in the high-temperature pyrolysis gas is catalytically cracked to obtain high-hydrogen fuel gas;

[0015] (4) continuously introducing the high-hydrogen fuel gas obtained in the atmospheric catalytic conversion furnace I into the atmospheric catalytic conversion furnace II, so that the alkanes in the high-hydrogen fuel gas are catalytically cracked to produce hydrogen gas, and the bottom of the atmospheric catalytic conversion furnace II produces hydrogen-rich fuel gas.

[0016] Preferably, the crushed biomass waste obtained in step (1) is added into the gradient pyrolysis device through a screw feeder, and the feeding speed is 0.5-5 kg / h.

[0017] Preferably, the temperature ranges of the baking section, the hot premixing section, the pyrolysis gasification section and the catalytic reforming section in step (2) are 250-300℃, 500-600℃, 750-800℃ and 900-1000℃, respectively.

[0018] Preferably, the mixture of pure oxygen and water vapor is continuously introduced into the catalytic reforming section, the inlet is located at the middle of the catalytic reforming section, the inlet direction is parallel to the ground, the flow rate of O2 is 100-200 mL / min, and the flow rate of water vapor is 0.5-2 g / min.

[0019] Preferably, when the height of the semi-coke in the gradient pyrolysis device exceeds the edge position below the inlet of the catalytic reforming section, the coke discharging is started, and when the height of the semi-coke in the gradient pyrolysis device is lower than the middle position of the catalytic reforming section, the coke discharging is stopped.

[0020] Preferably, the catalyst loaded in the atmospheric catalytic conversion furnace I is a nickel-iron-based catalyst with a mixture of ZSM-5 molecular sieve and aluminum refining waste residue as the carrier.

[0021] Preferably, the preparation method of the nickel-iron-based catalyst comprises the following steps:

[0022] (1) The aluminum refining waste residue is pretreated by acidification and high-temperature calcination to obtain porous aluminum refining waste residue;

[0023] (2) The porous aluminum refining waste residue is uniformly mixed with ZSM-5 molecular sieve at a mass ratio of 4:6 to obtain a composite carrier;

[0024] (3) The composite carrier is added to deionized water at a mass ratio of 1-2:10, then nickel nitrate and ferric chloride are added, and ultrasonic stirring is performed at 60-80℃ until the water is completely volatilized. Then the solid mixture is placed in air at 500-600℃ for 1.5-2h to obtain a nickel-iron-based catalyst. The mass ratio of nickel nitrate, ferric chloride, and composite carrier is 8:4:100.

[0025] Preferably, the packing density of the catalyst in the atmospheric catalytic conversion furnace I is 0.8-1.2 g / cm3.

[0026] Preferably, the catalyst loaded in the atmospheric catalytic conversion furnace II is a nickel-based catalyst with carbon molecular sieve as the carrier.

[0027] Preferably, the preparation method of the nickel-based catalyst comprises the following steps:

[0028] (1) The biochar is uniformly mixed with KOH at a mass ratio of 1:2, and activated at 500-600℃ under the protection of nitrogen for 1-2h, then heated to 900℃, and while keeping the nitrogen flowing, CO2 is also introduced for 2-4h to obtain activated carbon. The flow rate of CO2 is 50 mL / min;

[0029] (2) The macropores of the activated carbon are filled with carbon and deposited by benzene deposition method to form a multi-level pore carbon molecular sieve;

[0030] (3) The multi-level carbon molecular sieve is added to deionized water, the mass ratio of the multi-level carbon molecular sieve to the deionized water is 1-2:10, then nickel nitrate is added, and ultrasonic stirring is carried out at 60-80 DEG C until the moisture is completely volatilized, then calcination is carried out at 500-600 DEG C for 1.5-2h under the protection of nitrogen or inert gas to obtain a nickel-based catalyst.

[0031] Preferably, the biomass waste includes one or more than two combinations of pine sawdust, corn stalks, and poplar wood.

[0032] The present application has the following beneficial effects:

[0033] (1) The biomass raw material is fed into the cascade pyrolysis device through a screw feeder, and the carbon content and calorific value of the biomass raw material are increased through baking. The raw material continuously enters the hot premixing section, the pyrolysis gasification section, and the catalytic reforming section under the action of gravity. The temperature of the pyrolysis section is 600-800 DEG C. The semi-coke obtained by pyrolysis is deposited at the bottom under the action of gravity. With the accumulation of semi-coke, the semi-coke can be used as a catalyst for tar conversion, and part of the tar is converted. O2 / H2O is introduced into the catalytic reforming section to reform the tar and hydrocarbon gas and release heat, thereby achieving self-supply of heat and filtering fly ash caused by pyrolysis

[0034] (2) In the wood waste segmented pyrolysis device, 30-50% of the tar can be converted, but 50-70% of the tar is not converted. The high-temperature pyrolysis gas containing tar is introduced into the atmospheric pressure catalytic conversion furnace I. The nickel-iron-based catalyst with a mixture of ZSM-5 molecular sieve and aluminum refining waste residue as the carrier in the conversion furnace makes the tar further catalytically converted to obtain high-hydrogen fuel gas. The conversion temperature is 800-1000 DEG C, and the tar conversion rate can reach more than 99%.

[0035] (3) The high-hydrogen fuel gas still contains a certain amount of CH4 and other hydrocarbon gases, and the proportion of CO2 is slightly high. It needs to be catalytically reformed by the atmospheric pressure catalytic conversion furnace II to obtain the final hydrogen-rich fuel gas. The hydrogen content in the hydrogen-rich fuel gas is more than 70%.

[0036] (4) The present application uses cheap aluminum refining waste residue, pyrolysis semi-coke, and carbon molecular sieve as catalysts to catalytically convert tar steam through hierarchical and step-by-step thermochemical conversion, thereby significantly reducing the tar yield in the pyrolysis process and increasing the hydrogen yield. The aluminum refining waste residue couples with the molecular sieve to catalyze the tar cracking, thereby improving the effect of the cheap nickel-based catalyst on the tar cracking for hydrogen production. The carbon molecular sieve loaded with nickel catalytically reforms the hydrocarbon gas, so that the hydrogen proportion reaches more than 70%, and the energy utilization, reduction, harmless treatment, and resource utilization of the biomass waste, the aluminum refining waste residue, and the pyrolysis residue are achieved. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a schematic diagram of a biomass waste staged pyrolysis catalytic gasification hydrogen production process system structure provided by the present application.

[0038] In the figure: 101. baking section, 102. hot premixing section, 103. pyrolysis gasification section, 104. catalytic reforming section. DETAILED DESCRIPTION

[0039] The present application will be described in detail below in conjunction with the examples. However, it should be understood that the following examples are merely illustrative of the embodiments of the present application, and are not intended to limit the scope of the present application.

[0040] The stepped pyrolysis device used in Example 1 of the present application is the wood waste staged pyrolysis catalytic gasification hydrogen production device in Chinese invention patent CN114907869 A. The baking section, hot premixing section, pyrolysis gasification section and catalytic reforming section described in the present application correspond to the baking section 101, hot premixing section 102, pyrolysis gasification section 103 and catalytic reforming section 104 in the structure of the wood waste staged pyrolysis catalytic gasification hydrogen production device previously applied for patent by the research team of the present application.

[0041] The atmospheric catalytic converter I and the atmospheric catalytic converter II used in Example 1 of the present application are both atmospheric fixed bed reactors, purchased from Suzhou Furenande Experimental Equipment Co., Ltd., model FD-BC. During the reaction, the catalyst is loaded in the catalyst loading area of the atmospheric fixed bed reactor, and the loading compaction density is 0.8 g / cm 3 .

[0042] The aluminum smelting waste residue used in the following Example 1 of the present application (Huzhou Senge New Material Co., Ltd.) has the composition shown in Table 1:

[0043] Table 1

[0044] The catalyst loaded in the atmospheric catalytic converter I in the following Example 1 of the present application is a nickel-iron-based catalyst with a mixture of ZSM-5 molecular sieve and aluminum smelting waste residue as the carrier, and the preparation method is as follows:

[0045] (1) Soak the aluminum smelting waste residue in dilute sulfuric acid with a mass concentration of 30%, and stir for 4h for acidification pretreatment;

[0046] (2) Place the aluminum smelting waste residue after acidification pretreatment in air at 600℃ for calcination, and the calcination time is 3h, to obtain porous aluminum smelting waste residue;

[0047] (3) Mix the porous aluminum smelting waste residue and ZSM-5 molecular sieve uniformly according to a mass ratio of 4:6 to obtain a composite carrier;

[0048] (4) adding the composite carrier into deionized water, the mass ratio of the composite carrier to the deionized water being 1:10, then adding nickel nitrate and ferric chloride, and ultrasonic stirring and stirring at 60 DEG C until the moisture is completely volatilized, then placing the solid mixture in air at 550 DEG C for 2h to obtain the nickel-iron-based catalyst, the mass ratio of the nickel nitrate, the ferric chloride and the composite carrier being 8:4:100.

[0049] The ZSM-5 molecular sieve used in the following examples of the present application is ZSM-5, the silicon-aluminum ratio is 25, and is purchased from the Catalyst Factory of Nankai University.

[0050] The catalyst filled in the atmospheric catalytic converter II in Example 1 below is a nickel-based catalyst with a carbon molecular sieve as a carrier, and the preparation method of the nickel-based catalyst is as follows:

[0051] (1) mixing the biochar and KOH uniformly according to the mass ratio of 1:2, activating at 550 DEG C under the protection of nitrogen for 2h, then increasing the temperature to 900 DEG C, keeping nitrogen flowing while introducing CO2 to activate for 2h, and finally obtaining the activated carbon, the flow rate of CO2 being 50mL / min, and the volume flow rate ratio of CO2 to nitrogen being 1:1;

[0052] (2) through the benzene deposition method, placing 75g of the activated carbon in an atmospheric fixed bed, introducing toluene vapor at a flow rate of 0.5g / min, and reacting at 900 DEG C for 0.5h to obtain the hierarchical pore carbon molecular sieve;

[0053] (3) adding the hierarchical pore carbon molecular sieve into deionized water, the mass ratio of the hierarchical pore carbon molecular sieve to the deionized water being 1:10, then adding nickel nitrate, and ultrasonic stirring and stirring at 60 DEG C until the moisture is completely volatilized, then performing calcination at 550 DEG C under the protection of nitrogen for 2h to obtain the nickel-based catalyst.

[0054] The biochar in the preparation process of the nickel-based catalyst is pyrolytic carbon obtained by pyrolyzing pine sawdust at 800 DEG C under the protection of nitrogen for 0.5h.

[0055] In the present application, the tar yield = tar amount / biomass waste x 100%.

[0056] In the following examples of the present application, the content of hydrogen is expressed in mL / g, which refers to the volume of hydrogen obtained after the hydrogen production by the segmented pyrolysis and catalytic gasification of each g of biomass.

[0057] Example 1

[0058] A process system (the structure of the process device is shown in Fig. 1 of the accompanying drawings) for producing hydrogen by the segmented pyrolysis and catalytic gasification of biomass waste is as follows:

[0059] (1) drying the pine sawdust to less than 10% of moisture and crushing to 3mm;

[0060] (2) The crushed biomass waste obtained in step (1) is continuously fed into the cascade pyrolysis device as material through a screw feeder at a feeding speed of 5 kg / h. Under the action of gravity and the pre-mixing and stirring assembly in the cascade pyrolysis device, the material is sequentially treated in the roasting section, the hot pre-mixing section, the pyrolysis gasification section, and the catalytic reforming section to obtain semicoke and volatile matter. The temperatures of the roasting section, the hot pre-mixing section, the pyrolysis gasification section, and the catalytic reforming section are 250°C, 500°C, 750°C, and 900°C, respectively. A mixture of pure oxygen and water vapor is continuously introduced into the catalytic reforming section. The gas inlet is located in the middle of the catalytic reforming section, and the gas inlet direction is parallel to the ground. The flow rate of O2 is 100 mL / min, and the flow rate of water vapor is 0.5 g / min. When the height of the semicoke in the cascade pyrolysis device exceeds the edge position below the gas inlet of the catalytic reforming section, the semicoke is discharged. When the height of the semicoke in the cascade pyrolysis device is lower than the middle position of the catalytic reforming section, the semicoke is stopped. The volatile matter is filtered through the accumulated semicoke in the catalytic conversion section to obtain high-temperature pyrolysis gas. The high-temperature pyrolysis gas contains 450 mL / g of hydrogen, 55 mL / g of methane, 100 mL / g of carbon dioxide, and 175 mL / g of carbon monoxide. The tar yield is 8%.

[0061] (3) The high-temperature pyrolysis gas is continuously introduced into the atmospheric catalytic conversion furnace I through a pipeline. The tar in the high-temperature pyrolysis gas undergoes catalytic cracking in the atmospheric catalytic conversion furnace I at a reaction temperature of 1000°C to obtain high-hydrogen fuel gas. The high-hydrogen fuel gas contains 579 ml / g of hydrogen, 33 ml / g of methane, 125 ml / g of carbon dioxide, and 223 ml / g of carbon monoxide. The tar yield is reduced to 0.1%.

[0062] (4) The high-hydrogen fuel gas obtained in the atmospheric catalytic conversion furnace I is continuously introduced into the atmospheric catalytic conversion furnace II. The alkane gas in the high-hydrogen fuel gas undergoes catalytic cracking in the atmospheric catalytic conversion furnace II at a reaction temperature of 800°C to produce hydrogen. The gas at the bottom of the atmospheric catalytic conversion furnace II is collected to obtain hydrogen-rich fuel gas. The hydrogen-rich fuel gas contains 725 ml / g of hydrogen, 10 ml / g of methane, 55 ml / g of carbon dioxide, and 253 ml / g of carbon monoxide.

[0063] Example 2 is the same as Example 1, except that the temperatures in the roasting section, the hot pre-mixing section, the pyrolysis gasification section, and the catalytic reforming section in Example 2 are 200°C, 300°C, 600°C, and 800°C, respectively.

[0064] The high-temperature pyrolysis gas obtained in Example 2 contains 320 mL / g of hydrogen, 105 mL / g of methane, 120 mL / g of carbon dioxide, and 160 mL / g of carbon monoxide.

[0065] The high-hydrogen gas obtained in Example 2 has 490 mL / g of hydrogen, 65 mL / g of methane, 135 mL / g of carbon dioxide, and 180 mL / g of carbon monoxide, and the tar yield is reduced to 1%;

[0066] The hydrogen-rich gas obtained in Example 2 has 579 mL / g of hydrogen, 35 mL / g of methane, 95 mL / g of carbon dioxide, and 235 mL / g of carbon monoxide.

[0067] Example 3 is the same as Example 1, except that the temperatures in the roasting section, the hot premixing section, the pyrolysis and gasification section, and the catalytic reforming section in Example 3 are 300°C, 600°C, 800°C, and 1000°C, respectively.

[0068] The high-temperature pyrolysis gas obtained in Example 3 has 420 mL / g of hydrogen, 75 mL / g of methane, 65 mL / g of carbon dioxide, and 185 mL / g of carbon monoxide;

[0069] The high-hydrogen gas obtained in Example 3 has 510 mL / g of hydrogen, 40 mL / g of methane, 120 mL / g of carbon dioxide, and 220 mL / g of carbon monoxide, and the tar yield is reduced to 0.5%;

[0070] The hydrogen-rich gas obtained in Example 3 has 710 mL / g of hydrogen, 18 mL / g of methane, 56 mL / g of carbon dioxide, and 265 mL / g of carbon monoxide.

[0071] Example 4 is the same as Example 1, except that the catalyst used in the atmospheric catalytic conversion furnace I in Example 4 is prepared as follows:

[0072] (1) The aluminum refining waste residue is soaked in dilute sulfuric acid with a mass concentration of 30%, and stirred for 4 h for acidification pretreatment;

[0073] (2) The aluminum refining waste residue after acidification pretreatment is calcined in air at 600°C for 3 h to obtain porous aluminum refining waste residue;

[0074] (3) The porous aluminum refining waste residue is uniformly mixed with ZSM-5 molecular sieve at a mass ratio of 4:6 to obtain a composite carrier;

[0075] (4) The composite carrier is added to deionized water at a mass ratio of 1:10, and then nickel nitrate and ferric chloride are added. The mixture is ultrasonically stirred and stirred at 60°C until the water is completely volatilized. Then the solid mixture is calcined in air at 550°C for 2 h to obtain a nickel-iron-based catalyst. The mass ratio of nickel nitrate, ferric chloride, and the composite carrier is 4:1:100.

[0076] The high-temperature pyrolysis gas obtained in Example 4 has 450 mL / g of hydrogen, 55 mL / g of methane, 100 mL / g of carbon dioxide, and 175 mL / g of carbon monoxide.

[0077] The hydrogen gas in the high-hydrogen fuel gas obtained in Example 4 is 490 mL / g, the methane is 50 mL / g, the carbon dioxide is 115 mL / g, the carbon monoxide is 180 mL / g, and the tar yield is reduced to 0.4%;

[0078] The hydrogen gas in the high-hydrogen fuel gas obtained in Example 4 is 490 mL / g, the methane is 50 mL / g, the carbon dioxide is 115 mL / g, the carbon monoxide is 180 mL / g, and the tar yield is reduced to 0.4%;

[0079] Example 5 is the same as Example 1, except that the preparation method of the catalyst used in the atmospheric catalytic reformer I of Example 5 is as follows:

[0080] (1) The aluminum smelting waste residue is soaked in dilute sulfuric acid with a mass concentration of 30%, and stirred and reacted for 4 h for acidification pretreatment;

[0081] (2) The aluminum smelting waste residue after acidification pretreatment is placed in air at 600°C for calcination, and the calcination time is 3 h, to obtain a porous aluminum smelting waste residue;

[0082] (3) The porous aluminum smelting waste residue is uniformly mixed with ZSM-5 molecular sieve according to a mass ratio of 4:6 to obtain a composite carrier;

[0083] (4) The composite carrier is added to deionized water, and the mass ratio of the composite carrier to the deionized water is 1:10, then nickel nitrate and ferric chloride are added, and ultrasonic stirring is performed at 60°C until the water is completely volatilized, then the solid mixture is placed in air at 550°C for calcination for 2 h, to obtain a nickel-iron-based catalyst, and the mass ratio of the nickel nitrate, the ferric chloride, and the composite carrier is 6:2:100.

[0084] The hydrogen gas in the high-temperature pyrolysis gas obtained in Example 5 is 450 mL / g, the methane is 55 mL / g, the carbon dioxide is 100 mL / g, and the carbon monoxide is 175 mL / g;

[0085] The hydrogen gas in the high-hydrogen fuel gas obtained in Example 5 is 510 mL / g, the methane is 35 mL / g, the carbon dioxide is 115 mL / g, the carbon monoxide is 186 mL / g, and the tar yield is reduced to 0.4%;

[0086] The hydrogen gas in the high-hydrogen fuel gas obtained in Example 5 is 510 mL / g, the methane is 35 mL / g, the carbon dioxide is 115 mL / g, the carbon monoxide is 186 mL / g, and the tar yield is reduced to 0.4%;

[0087] Comparative Example 1 is the same as Example 1, except that the catalyst filled in the atmospheric catalytic reformer I in Comparative Example 1 is a nickel-iron-based catalyst with ZSM-5 molecular sieve as the carrier, and the preparation method is as follows:

[0088] ZSM-5 molecular sieve was added into deionized water, the mass ratio of ZSM-5 molecular sieve to deionized water was 1:10, then nickel nitrate and ferric chloride were added, and the mixture was ultrasonically stirred at 60°C until the water was completely volatilized, then the solid mixture was placed in air at 550°C for 2h, to obtain a nickel-iron-based catalyst, the mass ratio of nickel nitrate, ferric chloride and ZSM-5 molecular sieve was 8:4:100.

[0089] The hydrogen content in the high-temperature pyrolysis gas obtained in Comparative Example 1 was 450 mL / g, the methane content was 55 mL / g, the carbon dioxide content was 100 mL / g, and the carbon monoxide content was 175 mL / g;

[0090] The hydrogen content in the high-hydrogen fuel gas obtained in Comparative Example 1 was 520 mL / g, the methane content was 45 mL / g, the carbon dioxide content was 125 mL / g, and the carbon monoxide content was 196 mL / g, and the tar yield was reduced to 0.4%;

[0091] The hydrogen content in the high-hydrogen fuel gas obtained in Comparative Example 1 was 520 mL / g, the methane content was 45 mL / g, the carbon dioxide content was 125 mL / g, and the carbon monoxide content was 196 mL / g, and the tar yield was reduced to 0.4%;

[0092] Comparative Example 2 was the same as Example 1, except that the catalyst used in the atmospheric catalytic reformer I of Comparative Example 2 was a nickel-iron-based catalyst with aluminum smelting slag as the carrier, and the preparation method was as follows:

[0093] (1) The aluminum smelting slag was soaked in dilute sulfuric acid with a mass concentration of 30%, and stirred for 4h for acidification pretreatment;

[0094] (2) The aluminum smelting slag after acidification pretreatment was placed in air at 600°C for calcination, and the calcination time was 3h, to obtain porous aluminum smelting slag;

[0095] (3) The porous aluminum smelting slag was added into deionized water, the mass ratio of porous aluminum smelting slag to deionized water was 1:10, then nickel nitrate and ferric chloride were added, and the mixture was ultrasonically stirred at 60°C until the water was completely volatilized, then the solid mixture was placed in air at 550°C for 2h, to obtain a nickel-iron-based catalyst, the mass ratio of nickel nitrate, ferric chloride and porous aluminum smelting slag was 8:4:100.

[0096] The hydrogen content in the high-temperature pyrolysis gas obtained in Comparative Example 2 was 450 mL / g, the methane content was 55 mL / g, the carbon dioxide content was 100 mL / g, and the carbon monoxide content was 175 mL / g;

[0097] The hydrogen content in the high-hydrogen fuel gas obtained in Comparative Example 2 was 500 mL / g, the methane content was 50 mL / g, the carbon dioxide content was 145 mL / g, and the carbon monoxide content was 210 mL / g, and the tar yield was reduced to 1%;

[0098] The hydrogen gas in the hydrogen-rich fuel gas obtained in Comparative Example 2 was 628 mL / g, the methane was 25 mL / g, the carbon dioxide was 120 mL / g, and the carbon monoxide was 290 mL / g.

[0099] Comparative Example 3 was the same as Example 1, except that in Comparative Example 3, the porous aluminum refining waste residue and the ZSM-5 molecular sieve were mixed in a mass ratio of 7:3 to obtain a composite carrier.

[0100] The hydrogen gas in the high-temperature pyrolysis gas obtained in Comparative Example 3 was 450 mL / g, the methane was 55 mL / g, the carbon dioxide was 100 mL / g, and the carbon monoxide was 175 mL / g.

[0101] The hydrogen gas in the high-hydrogen fuel gas obtained in Comparative Example 3 was 510 mL / g, the methane was 45 mL / g, the carbon dioxide was 135 mL / g, and the carbon monoxide was 200 mL / g, and the tar yield was reduced to 0.6%.

[0102] The hydrogen gas in the hydrogen-rich fuel gas obtained in Comparative Example 3 was 682 mL / g, the methane was 20 mL / g, the carbon dioxide was 115 mL / g, and the carbon monoxide was 265 mL / g.

[0103] Comparative Example 4 was the same as Example 1, except that in Comparative Example 4, the porous aluminum refining waste residue and the ZSM-5 molecular sieve were mixed in a mass ratio of 1:9 to obtain a composite carrier.

[0104] The hydrogen gas in the high-temperature pyrolysis gas obtained in Comparative Example 4 was 450 mL / g, the methane was 55 mL / g, the carbon dioxide was 100 mL / g, and the carbon monoxide was 175 mL / g.

[0105] The hydrogen gas in the high-hydrogen fuel gas obtained in Comparative Example 4 was 505 mL / g, the methane was 45 mL / g, the carbon dioxide was 130 mL / g, and the carbon monoxide was 205 mL / g, and the tar yield was reduced to 0.8%.

[0106] The hydrogen gas in the hydrogen-rich fuel gas obtained in Comparative Example 4 was 665 mL / g, the methane was 22 mL / g, the carbon dioxide was 125 mL / g, and the carbon monoxide was 280 mL / g.

[0107] Comparative Example 5 was the same as Example 1, except that in Comparative Example 5, the baking temperature of the biomass waste was 150°C.

[0108] The hydrogen gas in the high-temperature pyrolysis gas obtained in Comparative Example 5 was 420 mL / g, the methane was 75 mL / g, the carbon dioxide was 110 mL / g, and the carbon monoxide was 180 mL / g.

[0109] The hydrogen gas in the high hydrogen fuel gas obtained in Comparative Example 5 was 520 mL / g, the methane was 55 mL / g, the carbon dioxide was 135 mL / g, and the carbon monoxide was 200 mL / g, and the tar yield was reduced to 0.2%;

[0110] The hydrogen gas in the hydrogen-rich fuel gas obtained in Comparative Example 5 was 679 mL / g, the methane was 20 mL / g, the carbon dioxide was 95 mL / g, and the carbon monoxide was 260 mL / g.

[0111] Comparative Example 6 was the same as Example 1, except that the catalyst loaded in the atmospheric catalytic reformer I of Comparative Example 6 was a nickel-based catalyst with a mixture of ZSM-5 molecular sieve and aluminum refining waste residue as the carrier, and the preparation method was as follows:

[0112] (1) The aluminum refining waste residue was soaked in dilute sulfuric acid with a mass concentration of 30%, and stirred for acidification pretreatment for 4 h;

[0113] (2) The aluminum refining waste residue after acidification pretreatment was calcined in air at 600°C for 3 h to obtain porous aluminum refining waste residue;

[0114] (3) The porous aluminum refining waste residue was mixed with ZSM-5 molecular sieve at a mass ratio of 4:6 to obtain a composite carrier;

[0115] (4) The composite carrier was added to deionized water at a mass ratio of 1:10, and then nickel nitrate was added, and the mixture was ultrasonically stirred and stirred at 60°C until the water was completely volatilized. Then the solid mixture was calcined in air at 550°C for 2 h to obtain a nickel-based catalyst. The mass ratio between nickel nitrate and the composite carrier was 12:100.

[0116] The hydrogen gas in the high-temperature pyrolysis gas obtained in Comparative Example 6 was 450 mL / g, the methane was 55 mL / g, the carbon dioxide was 100 mL / g, and the carbon monoxide was 175 mL / g;

[0117] The hydrogen gas in the high hydrogen fuel gas obtained in Comparative Example 6 was 493 mL / g, the methane was 41 mL / g, the carbon dioxide was 120 mL / g, and the carbon monoxide was 213 mL / g, and the tar yield was reduced to 1%;

[0118] The hydrogen gas in the hydrogen-rich fuel gas obtained in Comparative Example 6 was 690 mL / g, the methane was 18 mL / g, the carbon dioxide was 85 mL / g, and the carbon monoxide was 253 mL / g.

[0119] Comparative Example 7 was the same as Example 1, except that the catalyst loaded in the atmospheric catalytic reformer I of Comparative Example 7 was an iron-based catalyst with a mixture of ZSM-5 molecular sieve and aluminum refining waste residue as the carrier, and the preparation method was as follows:

[0120] (1) The aluminum smelting waste residue is soaked in dilute sulfuric acid with a mass concentration of 30%, and stirred for 4h to perform acidification pretreatment;

[0121] (2) The aluminum smelting waste residue after acidification pretreatment is calcined in air at 600℃ for 3h to obtain porous aluminum smelting waste residue;

[0122] (3) The porous aluminum smelting waste residue is mixed with ZSM-5 molecular sieve at a mass ratio of 4:6 to obtain a composite carrier;

[0123] (4) The composite carrier is added to deionized water at a mass ratio of 1:10, and then iron chloride is added, and the mixture is ultrasonically stirred and heated at 60℃ until the water is completely volatilized, and then the solid mixture is calcined in air at 550℃ for 2h to obtain a nickel-iron-based catalyst, and the mass ratio of iron chloride to composite carrier is 12:100.

[0124] The hydrogen content in the high-temperature pyrolysis gas obtained in Comparative Example 7 is 450mL / g, the methane content is 55mL / g, the carbon dioxide content is 100mL / g, and the carbon monoxide content is 175mL / g;

[0125] The hydrogen content in the high-hydrogen fuel gas obtained in Comparative Example 7 is 460mL / g, the methane content is 56mL / g, the carbon dioxide content is 160mL / g, and the carbon monoxide content is 166mL / g, and the tar yield is reduced to 2%;

[0126] The hydrogen content in the high-hydrogen fuel gas obtained in Comparative Example 7 is 460mL / g, the methane content is 56mL / g, the carbon dioxide content is 160mL / g, and the carbon monoxide content is 166mL / g, and the tar yield is reduced to 2%;

[0127] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the content of the specification, and must be determined according to the scope of the claims.

Claims

1. A process system for hydrogen production from biomass waste by catalytic gasification through staged pyrolysis, characterized in that, It comprises the following steps: (1) drying and crushing the biomass waste to below 3mm; (2) continuously adding the crushed biomass waste obtained in step (1) into a cascade pyrolysis device, and under the action of gravity, the material is sequentially treated in a roasting section, a hot premixing section, a pyrolysis gasification section and a catalytic reforming section to obtain semi-coke and volatile matter, the semi-coke obtained is discharged from the bottom of the cascade pyrolysis device at a fixed time, and the volatile matter is filtered through the semi-coke accumulated in the catalytic conversion section to obtain high-temperature pyrolysis gas; (3) continuously introducing the high-temperature pyrolysis gas into atmospheric catalytic conversion furnace I to make the tar in the high-temperature pyrolysis gas undergo catalytic cracking to obtain high-hydrogen fuel gas; (4) continuously introducing the high-hydrogen fuel gas obtained in atmospheric catalytic conversion furnace I into atmospheric catalytic conversion furnace II to make the alkane gas in the high-hydrogen fuel gas undergo catalytic cracking to produce hydrogen gas, and a hydrogen-rich fuel gas is generated at the bottom of atmospheric catalytic conversion furnace II.

2. A process system for hydrogen production by catalytic gasification of biomass waste through staged pyrolysis as claimed in claim 1, wherein, The crushed biomass waste obtained in step (1) is added into the cascade pyrolysis device through a screw feeder, and the feeding speed is 0.5-5kg / h.

3. A process system for hydrogen production by catalytic gasification of biomass waste through staged pyrolysis as claimed in claim 1, wherein, The temperature ranges of the roasting section, the hot premixing section, the pyrolysis gasification section and the catalytic reforming section in step (2) are 250-300℃, 500-600℃, 750-800℃ and 900-1000℃, respectively.

4. The process system for hydrogen production from biomass waste by catalytic gasification through staged pyrolysis according to claim 1, wherein, A mixture of pure oxygen and water vapor is continuously introduced into the catalytic reforming section, the inlet is located in the middle of the catalytic reforming section, the inlet direction is parallel to the ground, the flow rate of O2 is 100-200mL / min, and the flow rate of water vapor is 0.5-2g / min.

5. The process system for hydrogen production from biomass waste by catalytic gasification through staged pyrolysis according to claim 1, wherein, When the height of the semi-coke in the cascade pyrolysis device exceeds the edge position below the inlet of the catalytic reforming section, the semi-coke is discharged, and when the height of the semi-coke in the cascade pyrolysis device is lower than the middle position of the catalytic reforming section, the semi-coke is stopped.

6. The process system for hydrogen production from biomass waste by catalytic gasification through staged pyrolysis according to claim 1, wherein, The catalyst filled in atmospheric catalytic conversion furnace I is a nickel-iron-based catalyst with a mixture of HZSM-5 molecular sieve and aluminum refining waste residue as the carrier.

7. A process system for hydrogen production by catalytic gasification of biomass waste through staged pyrolysis as claimed in claim 6, wherein, The preparation method of the nickel-iron-based catalyst comprises the following steps: (1) after acid pretreatment and high-temperature roasting of aluminum refining waste residue, porous aluminum refining waste residue is obtained; (2) the porous aluminum refining waste residue is uniformly mixed with HZSM-5 molecular sieve at a mass ratio of 0-7:3-10 to obtain a composite carrier; (3) the composite carrier is added to deionized water at a mass ratio of 1-10:100, then nickel nitrate and ferric chloride are added, and ultrasonic stirring is carried out at 60-80℃ until the water is completely volatilized, then the solid mixture is calcined at 500-600℃ in air for 1.5-2h to obtain the nickel-iron-based catalyst, and the mass ratio of nickel nitrate, ferric chloride and composite carrier is 8:4:

100.

8. The process system for hydrogen production from biomass waste by catalytic gasification through staged pyrolysis according to claim 1, wherein, The packing density of the catalyst in the atmospheric catalytic converter I is 0.8-1.2 g / cm 3 .

9. The process system for hydrogen production from biomass waste by catalytic gasification through staged pyrolysis according to claim 1, wherein, The catalyst filled in atmospheric catalytic conversion furnace II is a nickel-based catalyst with carbon molecular sieve as the carrier.

10. The process system for hydrogen production from biomass waste by catalytic gasification through staged pyrolysis according to claim 9, wherein, The preparation method of the nickel-based catalyst comprises the following steps: (1) uniformly mix biochar and KOH at a mass ratio of 1:0.5-4, and perform chemical activation under the protection of nitrogen at 500-600℃ for 1-2h, then increase the temperature to 800-1000℃, keep the nitrogen flowing while introducing CO2 to perform physical activation for 2-4h to obtain activated carbon; (2) by benzene deposition method, toluene vapor is passed at a flow rate of 0.2-1.5 g / min, under the condition of 600-900 ℃, for 0.5-1.5 h, to carry out pore filling carbonization and deposition on the macropore of the activated carbon, to form a hierarchical porous carbon molecular sieve; (3) the hierarchical porous carbon molecular sieve is added into deionized water, the mass ratio of the hierarchical porous carbon molecular sieve to the deionized water is 1-2:10, then nickel nitrate is added, and ultrasonic stirring is carried out at 60-80 ℃ until the water is completely volatilized, then calcination is carried out at 500-600 ℃ for 1.5-2.0 h under the protection of nitrogen or inert gas, to obtain a nickel-based catalyst.

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