Multi-stage directional regulation of waste pyrolysis gasification-coordinated hydrogen production process with gas-solid phase reforming

Abstract

This invention provides a multi-stage directional control process for waste pyrolysis and gasification combined with gas-solid phase reforming for hydrogen production, comprising the following steps: First-stage control: pretreatment and graded feeding, using physical-chemical directional methods to crush, sort, dry, and catalytically coat the waste; Second-stage control: low-temperature pyrolysis with directional dechlorination, performing thermochemical directional conversion of plastic and biomass waste at 350-450℃; Third-stage control: gasification-melting synergistic directional control, achieving gas-solid phase coupling reaction in a dual fluidized bed at 800-900℃; Fourth-stage control: multi-stage gas-solid phase reforming, improving hydrogen yield through catalytic-adsorption synergy in a moving bed at 700℃; Fifth-stage control: deep purification and hydrogen enhancement, selectively oxidizing syngas using chemical looping combustion to release hydrogen with a purity ≥99.99%. This invention uses molten ash as a catalytic carrier: utilizing the Fe-Ce active sites in the molten ash to simultaneously achieve tar cracking and syngas reforming, effectively improving tar conversion rate.

Description

Technical Field

[0001] This invention relates to the field of waste resource utilization and energy utilization technology, specifically a multi-stage directional control process for waste pyrolysis gasification and gas-solid phase reforming for synergistic hydrogen production. Background Technology

[0002] Traditional waste pyrolysis gasification hydrogen production processes generally suffer from bottlenecks such as "mixed components, disordered reactions, high tar, low hydrogen, and high energy consumption." Typical "one-pot" pyrolysis leads to the simultaneous pyrolysis of plastics and biomass, chlorine corrosion of equipment, tar blockage of pipelines, and subsequent expensive PSA purification. The system has an energy efficiency of less than 35% and high carbon emissions.

[0003] Existing technologies lack the concept of "multi-level targeted regulation" for the multi-component characteristics of waste, and cannot achieve the synergistic goal of near-zero tar emissions, high-purity hydrogen production, and near-zero CO2 release. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a multi-stage directional control process for waste pyrolysis gasification combined with gas-solid phase reforming for hydrogen production, thereby resolving the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention provides a multi-stage directional control process for waste pyrolysis gasification combined with gas-solid phase reforming for hydrogen production, comprising the following steps:

[0006] Primary control: Pre-treatment and graded feeding, using physical-chemical directional methods to crush, sort, dry and catalytically coated waste;

[0007] Secondary control: Low-temperature pyrolysis and targeted dechlorination, performing thermochemical targeted conversion of plastic and biomass waste at 350-450 ℃;

[0008] Three-stage regulation: gasification and melting are coordinated and directional, realizing gas-solid phase coupling reaction in a dual fluidized bed at 800-900 ℃;

[0009] Four-stage regulation: multi-stage gas-solid phase reforming to improve hydrogen yield through catalytic-adsorption synergy in a 700 ℃ moving bed;

[0010] Five-level regulation: deep purification and hydrogen purification, using chemical loop combustion to selectively oxidize syngas to release hydrogen with a purity of ≥99.99%;

[0011] Six-level regulation: waste heat recovery and carbon capture, achieving an energy-matter closed loop through organic Rankine cycle and CO2 mineralization.

[0012] As a further preferred option, the primary regulation includes:

[0013] Magnetic separation-eddy current separation removes metals and crushes them to a particle size of <50 mm;

[0014] The residual heat from subsequent processes at 200 °C is used for low-temperature drying to reduce the moisture content to <15%.

[0015] Spray 0.3-0.5 wt% Ni-Mg / Al2O3 slurry on biomass waste and 0.8-1.2 wt% Fe-Ce / ZSM-5 slurry on plastic waste.

[0016] As a further preferred option, the secondary control is carried out in a spiral propulsion low-temperature pyrolysis furnace, which is divided into three temperature control zones: 350 ℃, 400 ℃, and 450 ℃, with a residence time of 15-25 min. During the dehydrochlorination of plastic waste, 2wt% CaO is added for in-situ absorption, and biomass waste is deoxygenated to generate CO2 / CO. Volatile matter is separated by a SAPO-34 molecular sieve membrane, with a C2-C4 light hydrocarbon enrichment rate of ≥80%, and heavy tar is recycled to the gasification and melting zone.

[0017] As a further preferred option, the three-stage control adopts a dual fluidized bed gasifier, with the lower gasification zone operating at a temperature of 800-900 ℃, using oxygen-enriched steam as the gasifying agent, an O2 / H2O molar ratio of 0.25-0.35, and an apparent gas velocity of 1.0-1.5 m / s; the upper reforming zone is injected with atomized low-temperature pyrolysis tar, which undergoes catalytic cracking at Fe-Ce active sites on the surface of the molten ash, achieving a tar conversion rate of ≥90%, and increasing the H2 / CO molar ratio from 0.8 to 1.5.

[0018] As a further preferred embodiment, the Fe-Ce active sites in the molten ash are formed in the following manner:

[0019] Fe2O3 and CeO2 are mechanically mixed at a mass ratio of 3:1 and then incorporated into the waste material at a dosage of 0.5-1.0 wt%.

[0020] Under melting conditions >1300 ℃, Fe-Ce oxides are embedded in the glassy phase of ash slag, forming a specific surface area ≥50 m². 2 / g of catalyst layer.

[0021] As a further preferred embodiment, the four-stage controlled moving bed reformer is filled with a Ni-CaO / Al2O3 bifunctional catalyst-adsorbent, wherein the Ni loading is 12-18 wt% and the CaO particle size is 1-2 mm; and the reformer is operated at 700 ℃ and a space velocity of 1500-2500 h⁻¹. -1 Under the conditions, the CH4 dry reforming conversion rate is ≥85%, the CO2 capture rate of CaO in situ carbonation is ≥90%, and the catalyst is regenerated and recycled after calcination at 850 ℃.

[0022] As a further preferred embodiment, the five-stage controlled chemical looping combustion system includes:

[0023] The fuel reactor operates at 550-650 ℃, using Fe2O3 oxygen carrier to selectively oxidize CO / H2 to CO2 / H2O, achieving a hydrogen purity ≥99.99%.

[0024] The air reactor operates at a temperature of 850-950 ℃. Fe3O4 is oxidized and regenerated, releasing heat. This heat is supplied to the gasification and melting zone through an internal heat exchanger.

[0025] As a further preferred option, the waste heat recovery of the six-stage regulation adopts an organic Rankine cycle (ORC), with R245fa as the working fluid, an evaporation temperature of 110-130 ℃, a condensation temperature of 25-35 ℃, and a power generation efficiency of ≥20%; the sensible heat of the molten slag is recovered by a slag-gas heat exchanger and used to drive the ORC.

[0026] As a further preferred embodiment, the six-level controlled CO2 mineralization step includes:

[0027] The steel slag was crushed to <100 μm and reacted with the captured CO2 in a stirred tank at 60 °C with a liquid-to-solid ratio of 4-6:1.

[0028] The purity of the CaCO3 product generated is ≥95%, and the CO2 fixation rate is ≥80%.

[0029] This invention provides a multi-stage directional control process for hydrogen production via waste pyrolysis gasification and gas-solid phase reforming, which has the following advantages:

[0030] Multi-level targeted control mechanism: Breaking through the traditional "one-pot" pyrolysis, it achieves "classified and targeted conversion" of waste components (plastics / biomass / kitchen waste) through six-level step-by-step control;

[0031] Synergistic Gas-Solid Reforming: Molten Ash as Catalytic Support: Utilizing the Fe-Ce active sites in molten ash, tar cracking (solid phase) and syngas reforming (gas phase) are simultaneously achieved, increasing tar conversion rate from the traditional 70% to >90%;

[0032] Bifunctional catalyst-adsorbent: Ni-CaO material captures CO2 simultaneously during the reforming reaction, reducing energy consumption. Attached Figure Description

[0033] Figure 1 This is a flow chart of the waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process of the present invention;

[0034] Figure 2 This is a block diagram of the waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production system of the present invention. Detailed Implementation

[0035] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0036] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0037] like Figure 1 As shown, this embodiment of the invention provides a multi-stage directional control process for hydrogen production via waste pyrolysis gasification and gas-solid phase reforming, comprising the following steps:

[0038] S1: Primary control: Pretreatment and graded feeding, using physical-chemical directional methods to crush, sort, dry and catalytically coated waste;

[0039] The primary regulation includes:

[0040] Magnetic separation-eddy current separation removes metals and crushes them to a particle size of <50 mm;

[0041] The residual heat from subsequent processes at 200 °C is used for low-temperature drying to reduce the moisture content to <15%.

[0042] Spraying 0.3-0.5 wt% Ni-Mg / Al2O3 slurry on biomass waste and 0.8-1.2 wt% Fe-Ce / ZSM-5 slurry on plastic waste achieves source-directed catalysis.

[0043] S2: Secondary control: Low-temperature pyrolysis and directional dechlorination, thermochemical directional conversion of plastic and biomass waste at 350-450 ℃;

[0044] The secondary control is carried out in a spiral propulsion low-temperature pyrolysis furnace, which is divided into three temperature control zones: 350 ℃, 400 ℃, and 450 ℃, with a residence time of 15-25 min. During the dehydrochlorination of plastic waste, 2 wt% CaO is added for in-situ absorption, while biomass waste is deoxygenated to generate CO2 / CO. Volatile matter is separated by a SAPO-34 molecular sieve membrane, with a C2-C4 light hydrocarbon enrichment rate ≥80%, and heavy tar is recycled to the gasification and melting zone.

[0045] S3: Three-stage regulation: gasification and melting are coordinated and directional, realizing gas-solid phase coupling reaction in a dual fluidized bed at 800-900 ℃;

[0046] The three-stage control adopts a dual fluidized bed gasifier. The operating temperature of the lower gasification zone is 800-900 ℃, with oxygen-enriched steam as the gasifying agent, an O2 / H2O molar ratio of 0.25-0.35, and an apparent gas velocity of 1.0-1.5 m / s. The upper reforming zone is injected with atomized low-temperature pyrolysis tar, which is catalytically decomposed at Fe-Ce active sites on the surface of molten ash. The tar conversion rate is ≥90%, and the H2 / CO molar ratio is increased from 0.8 to 1.5.

[0047] The Fe-Ce active sites in the molten ash are formed in the following manner:

[0048] Fe2O3 and CeO2 are mechanically mixed at a mass ratio of 3:1 and then incorporated into the waste material at a dosage of 0.5-1.0 wt%.

[0049] Under melting conditions >1300 ℃, Fe-Ce oxides are embedded in the glassy phase of ash slag, forming a specific surface area ≥50 m². 2 / g of catalyst layer.

[0050] S4: Four-stage regulation: multi-stage gas-solid phase reforming, which improves hydrogen yield through catalytic-adsorption synergy in a 700 °C moving bed;

[0051] The four-stage controlled moving bed reformer is filled with a Ni-CaO / Al2O3 bifunctional catalyst-adsorbent, wherein the Ni loading is 12-18 wt% and the CaO particle size is 1-2 mm; it operates at 700 ℃ and a space velocity of 1500-2500 h⁻¹. -1 Under the conditions, the CH4 dry reforming conversion rate is ≥85%, the CO2 capture rate of CaO in situ carbonation is ≥90%, and the catalyst is regenerated and recycled after calcination at 850 ℃.

[0052] S5: Five-level regulation: deep purification and hydrogen purification, using chemical looping combustion (CLC) to selectively oxidize syngas to release hydrogen with a purity ≥99.99%;

[0053] The five-stage regulated chemical looping combustion (CLC) system includes:

[0054] The fuel reactor operates at 550-650 ℃, using Fe2O3 oxygen carrier to selectively oxidize CO / H2 to CO2 / H2O, achieving a hydrogen purity ≥99.99%.

[0055] The air reactor operates at a temperature of 850-950 ℃. Fe3O4 is oxidized and regenerated, releasing heat. This heat is supplied to the gasification and melting zone through an internal heat exchanger.

[0056] S6: Six-level regulation: waste heat recovery and carbon capture, achieving an energy-matter closed loop through the Organic Rankine Cycle (ORC) and CO2 mineralization.

[0057] The waste heat recovery system with six-stage regulation adopts an organic Rankine cycle (ORC), with R245fa as the working fluid, an evaporation temperature of 110-130 ℃, a condensation temperature of 25-35 ℃, and a power generation efficiency of ≥20%. The sensible heat of the molten slag is recovered through a slag-gas heat exchanger and then used to drive the ORC.

[0058] The six-level regulated CO2 mineralization steps include:

[0059] The steel slag was crushed to <100 μm and reacted with the captured CO2 in a stirred tank at 60 °C with a liquid-to-solid ratio of 4-6:1.

[0060] The CaCO3 product generated has a purity of ≥95% and a CO2 fixation rate of ≥80%, achieving negative carbon emissions from the system.

[0061] like Figure 2 As shown, this embodiment also provides a waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production system, used to realize the above-mentioned waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process, including:

[0062] The pretreatment unit includes a magnetic separator, an eddy current separator, a three-stage crusher, a rotary drum dryer, and a dual-fluid nozzle catalytic coating device.

[0063] The low-temperature pyrolysis unit features a three-stage temperature-controlled spiral propeller pyrolysis furnace and a SAPO-34 molecular sieve membrane separator.

[0064] The gasification and melting unit includes a dual fluidized bed gasifier, a molten slag quench-granulator, and an online monitoring module for Fe-Ce active sites.

[0065] The moving bed reforming unit has a Ni-CaO / Al2O3 catalyst-adsorbent moving bed and a CaCO3 calcination regenerator;

[0066] The CLC unit has a fuel reactor, an air reactor, and a Fe2O3 oxygen carrier circulation loop.

[0067] The waste heat recovery-carbon capture unit includes an ORC power generation module, a slag-gas heat exchanger, a CO2 mineralization reactor, and a CaCO3 product separator.

[0068] The waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process provided in this embodiment achieves "classified directional conversion" of waste components through a "six-stage directional control-gas-solid synergy" mechanism, following a progressive path of physical-chemical-thermochemical-gas-solid coupling-catalytic adsorption-chemical loop-energy closed loop. A Fe-Ce catalytic layer is generated in situ from the molten ash, increasing the tar conversion rate from 70% to >90%. Simultaneous CH4 reforming and CO2 capture are completed using Ni-CaO bifunctional materials, eliminating the need for a PSA unit. Chemical looping combustion (CLC) produces 99.99% hydrogen in one step, and ORC and CO2 mineralization recover waste heat and fix >80% carbon. The system's power generation efficiency is ≥20%, and the overall energy efficiency is >55%, achieving high-value hydrogen production from waste-to-carbon waste.

[0069] Example 1

[0070] A municipal solid waste hydrogen production project was established in a southern city, employing a multi-stage directional control process of waste pyrolysis gasification and gas-solid phase reforming to produce hydrogen continuously for 24 hours.

[0071] The waste composition (by weight) was as follows: kitchen waste 45%, plastics 25% (of which PVC accounted for 8%), paper 15%, wood and bamboo 10%, and textiles 5%. The received basis moisture content was 38%, and the lower calorific value was 8.4 MJ·kg⁻¹. -1 .

[0072] Primary control (pretreatment and graded feeding);

[0073] Crushing-sorting: Jaw crusher → Shear crusher → Impact mill, discharge particle size 100% < 50 mm; Magnetic separator removes iron at a rate of 98.5%, eddy current separator removes aluminum and copper at a rate of 96%.

[0074] Graded drying: The rotary drum dryer uses the subsequent ORC condensate and 200 ℃ flue gas for indirect heat exchange, and after a residence time of 30 minutes, the moisture content is reduced to 13.8%.

[0075] Catalytic coating: Biomass materials (kitchen waste, paper, wood and bamboo) are sprayed with Ni-Mg / Al2O3 slurry with a Ni loading of 0.45 wt%; plastic materials are sprayed with Fe-Ce / ZSM-5 slurry with a Fe loading of 1.0 wt%; the slurry coverage is 92%.

[0076] Secondary control (low-temperature pyrolysis directional dechlorination);

[0077] The spiral propulsion pyrolysis furnace has three-stage temperature control: 350 ℃ / 400 ℃ / 450 ℃, with a total residence time of 22 min.

[0078] CaO was premixed with plastics at 2 wt%, and the HCl absorption rate was 96%. After separation by SAPO-34 membrane, the C2-C4 yield was 82%, and the heavy tar reflux ratio was 35%.

[0079] Three-level regulation (coordinated directional control of gasification and melting);

[0080] Dual fluidized bed operating parameters: lower section 870 ℃, O2 / H2O=0.30, apparent gas velocity 1.25 m·s -1 The melting zone is 1350 ℃, the ash slag melting rate is 100%, and the heavy metal solidification rate is 99.2%.

[0081] The tar atomization particle size is 80 μm. Under the action of Fe-Ce active sites on the surface of the molten slag, the tar conversion rate is 93%, and the H2 / CO ratio is increased from 0.83 to 1.52.

[0082] Four-level regulation (multi-stage gas-solid phase reforming);

[0083] Moving bed rebalancer 700 ℃, air velocity 2000 h -1 15 kg of Ni-CaO / Al2O3 catalyst was loaded.

[0084] The CH4 dry reforming conversion rate is 87%, the CaO carbonation CO2 capture rate is 91%, the catalyst is regenerated by calcination at 850℃ with N2 for 10 min, and the activity decreases by <5% after 110 cycles.

[0085] Five-level regulation (deep purification and hydrogen enhancement);

[0086] CLC fuel reactor at 620℃, Fe2O3 oxygen carrier circulation rate 4.8 kg·h -11 Hydrogen purity 99.993%, CO and CH4 impurities <10ppm.

[0087] The air reactor at 900℃ exhibits an exothermic oxidation reaction of 1.05 MJ·kg⁻¹. -1 120 kg·h of saturated steam at 0.45 MPa is generated through an internal heat exchanger. -1 .

[0088] Six-level regulation (waste heat recovery and carbon capture);

[0089] ORC working fluid R245fa, evaporation temperature 120℃ / condensation temperature 30℃, net power generation 52kW, system power self-sufficiency rate 63%.

[0090] CO2 capture flow rate 42 kg·h -1 , with 210 kg·h -1 Steel slag (80 μm particle size) reacted in a stirred tank at 60 °C and a liquid-to-solid ratio of 5:1 for 30 min, with a CaCO3 yield of 82% and a CO2 fixation rate of 81%.

[0091] Output results: Hydrogen yield 123 g·kg -1 Waste; System energy efficiency 66.4% (LHV benchmark);

[0092] Carbon emission reduction: 1.54 tCO2-eq·t -1 Rubbish;

[0093] The molten slag glass product meets the requirements of GB / T41015-2021 building materials.

[0094] Example 2

[0095] Based on Example 1, the proportion of plastics is increased to 40% (PVC 15%), and the adjustments are as follows:

[0096] The amount of CaO added during low-temperature pyrolysis was increased to 3 wt%, while the HCl absorption rate remained at 97%.

[0097] The temperature of the vaporization and melting zone was reduced to 820℃, and the O2 / H2O ratio was adjusted to 0.28 to avoid PVC-derived chlorine corrosion.

[0098] The oxygen carrier in CLC was changed to a Fe2O3-MgAl2O4 composite carrier, which increased the chlorine adsorption capacity by 40% while maintaining the hydrogen purity at ≥99.99%.

[0099] The system hydrogen yield is 118 g·kg. -1 Carbon emission reduction of 1.49 tCO2-eq·t -1 .

[0100] Example 3

[0101] Based on Example 1, the proportion of biomass was increased to 70%, and the proportion of plastics was reduced to 10%.

[0102] Remove the Fe-Ce / ZSM-5 coating and retain only the Ni-Mg / Al2O3 coating;

[0103] The moving bed reformer temperature dropped to 680℃, the CH4 dry reforming conversion rate was 80%, but the CaO CO2 capture rate increased to 94%.

[0104] ORC power generation dropped to 48kW, but hydrogen production increased to 131g·kg⁻¹.-1 .

[0105] Example 4

[0106] 7-day average operation data of the industrial demonstration line:

[0107] Processing capacity 5t·h -1 ;

[0108] Hydrogen production: 615 Nm 3 ·h -1 (Purity 99.99%)

[0109] 0.75 t·h of molten slag -1 (Vitreous content 96%)

[0110] The system availability rate is 94%, and the catalyst regeneration cycle is 12 hours.

[0111] Example 5

[0112] Replacing CaO with a CaO-CaZrO3 composite adsorbent reduced the regeneration temperature to 800℃, and the activity decreased by less than 3% after 150 cycles; the regeneration heat of the CLC oxygen carrier was reduced from 1.05 MJ·kg⁻¹. -1 Reduced to 0.92 MJ·kg -1 The system's total energy consumption decreased by 4.7%.

[0113] Table 1 Results of an Example of a Multi-Stage Directional Controlled Hydrogen Production Process Based on Waste Pyrolysis Gasification and Gas-Solid Phase Reforming

[0114] Serial Number Hydrogen yield (g·kg⁻¹ waste) Hydrogen purity (%) System energy efficiency (LHV, %) Carbon emission reduction (T CO2 - EQ·T-1 waste) Glass content of molten slag (%) System availability (%) Example 1 123 99.993 66.4 1.54 96 94 Example 2 118 99.99 65.1 1.49 95 93 Example 3 131 99.99 67.2 1.61 97 95 Example 4 123 99.99 66.0 1.53 96 94 Example 5 124 99.99 68.1 1.55 96 95

[0115] Table 1 shows the following: Multi-stage directional control of waste pyrolysis gasification combined with gas-solid reforming for hydrogen production:

[0116] Stable and excellent hydrogen production: The hydrogen yield remained at 118–131 g·kg⁻ in all embodiments. 1 Among the waste samples, the hydrogen purity was ≥99.99%, indicating that the process has good adaptability to fluctuations in waste composition. The high biomass condition (Example 3) had the highest yield, while the high plastic condition (Example 2) had a slightly lower yield but still higher than 110 g·kg. -1 .

[0117] Simultaneous improvement in energy efficiency and carbon emission reduction: System energy efficiency (LHV benchmark) is between 65% and 68%, with carbon emission reductions of 1.49–1.61 t CO2-eq·t. -1 The energy efficiency of the waste is significantly better than that of traditional incineration or single gasification technologies; after adopting the CaO-CaZrO3 composite adsorbent (Example 5), the energy efficiency is further improved by about 2 percentage points.

[0118] The resource utilization effect of molten slag is consistent: the glass content of molten slag is stable at 95-97%, heavy metals are completely solidified, and it meets the standards for building material utilization; different waste components have limited impact on slag quality.

[0119] High operational reliability: Industrial demonstrations over 24 hours to 7 days show that the system availability remains at 93–95%, the catalyst and adsorbent regeneration cycle is ≥12 hours, and the device has the ability to operate stably for a long period of time.

[0120] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-stage directional control process for waste pyrolysis gasification combined with gas-solid phase reforming for hydrogen production, characterized in that, Includes the following steps: Primary control: Pre-treatment and graded feeding, using physical-chemical directional methods to crush, sort, dry and catalytically coated waste; Secondary control: Low-temperature pyrolysis and targeted dechlorination, performing thermochemical targeted conversion of plastic and biomass waste at 350-450 ℃; Three-stage regulation: gasification and melting are coordinated and directional, realizing gas-solid phase coupling reaction in a dual fluidized bed at 800-900 ℃; Four-stage regulation: multi-stage gas-solid phase reforming to improve hydrogen yield through catalytic-adsorption synergy in a 700 ℃ moving bed; Five-level regulation: deep purification and hydrogen purification, using chemical loop combustion to selectively oxidize syngas to release hydrogen with a purity of ≥99.99%; Six-level regulation: waste heat recovery and carbon capture, achieving energy-matter closed loop through organic Rankine cycle and CO2 mineralization; The three-stage control system employs a dual-fluidized bed gasifier. The lower gasification zone operates at a temperature of 800-900 ℃, using oxygen-enriched steam as the gasifying agent, with an O2 / H2O molar ratio of 0.25-0.35 and an apparent gas velocity of 1.0-1.5 m / s. The upper reforming zone is injected with atomized low-temperature pyrolysis tar, which undergoes catalytic cracking at Fe-Ce active sites on the surface of the molten ash slag. The tar conversion rate is ≥90%, and the H2 / CO molar ratio is increased from 0.8 to 1.

5. The Fe-Ce active sites in the molten ash are formed in the following manner: Fe2O3 and CeO2 are mechanically mixed at a mass ratio of 3:1 and then incorporated into the waste material at a dosage of 0.5-1.0 wt%. Under melting conditions >1300 ℃, Fe-Ce oxides are embedded in the glassy phase of ash slag, forming a specific surface area ≥50 m². 2 / g of catalyst layer.

2. The waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process according to claim 1, characterized in that, The primary regulation includes: Magnetic separation-eddy current separation removes metals and crushes them to a particle size of <50 mm; The residual heat from subsequent processes at 200 °C is used for low-temperature drying to reduce the moisture content to <15%. Spray 0.3-0.5 wt% Ni-Mg / Al2O3 slurry on biomass waste and 0.8-1.2 wt% Fe-Ce / ZSM-5 slurry on plastic waste.

3. The waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process according to claim 2, characterized in that, The secondary control is carried out in a spiral propulsion low-temperature pyrolysis furnace, which is divided into three temperature control zones: 350 ℃, 400 ℃, and 450 ℃, with a residence time of 15-25 min. During the dehydrochlorination of plastic waste, 2 wt% CaO is added for in-situ absorption, and biomass waste is deoxygenated to generate CO2 / CO. Volatile matter is separated by SAPO-34 molecular sieve membrane, with a C2-C4 light hydrocarbon enrichment rate of ≥80%, and heavy tar is recycled to the gasification and melting zone.

4. The waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process according to claim 1, characterized in that, The four-stage controlled moving bed reformer is filled with a Ni-CaO / Al2O3 bifunctional catalyst-adsorbent, wherein the Ni loading is 12-18 wt% and the CaO particle size is 1-2 mm; it operates at 700 ℃ and a space velocity of 1500-2500 h⁻¹. -1 Under the conditions, the CH4 dry reforming conversion rate is ≥85%, the CO2 capture rate of CaO in situ carbonation is ≥90%, and the catalyst is regenerated and recycled after calcination at 850 ℃.

5. The waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process according to claim 4, characterized in that, The five-stage controlled chemical looping combustion system includes: The fuel reactor operates at 550-650 ℃, using Fe2O3 oxygen carrier to selectively oxidize CO / H2 to CO2 / H2O, achieving a hydrogen purity ≥99.99%. The air reactor operates at a temperature of 850-950 ℃. Fe3O4 is oxidized and regenerated, releasing heat. This heat is supplied to the gasification and melting zone through an internal heat exchanger.

6. The waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process according to claim 1, characterized in that, The waste heat recovery system with six-stage regulation adopts an organic Rankine cycle (ORC), with R245fa as the working fluid, an evaporation temperature of 110-130 ℃, a condensation temperature of 25-35 ℃, and a power generation efficiency of ≥20%. The sensible heat of the molten slag is recovered through a slag-gas heat exchanger and then used to drive the ORC.

7. The waste pyrolysis gasification multi-stage directional control-gas-solid phase reforming synergistic hydrogen production process according to claim 1, characterized in that, The six-level regulated CO2 mineralization steps include: The steel slag was crushed to <100 μm and reacted with the captured CO2 in a stirred tank at 60 °C with a liquid-to-solid ratio of 4-6:

1. The purity of the CaCO3 product generated is ≥95%, and the CO2 fixation rate is ≥80%.

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