A coal gas fermentation stage ultra-deep purification system and method based on cracking-precision screening-flow orientation regulation

Abstract

The present application provides a coal gas fermentation level ultra-deep purification system and method based on cracking-precision screening-flow directional regulation, belonging to the technical field of coal gas deep purification and resource utilization. The method is to take coal gas through the cross-media synergistic cracking unit, the supramolecular biomimetic MOFs intelligent adaptive screening unit, the PN / A-Candida utilis metabolic flow precision regulation unit and the full-element grading resource recovery unit in turn, and is controlled by the digital twin-blockchain carbon footprint traceability and intelligent regulation PLC intelligent control system, so as to achieve the purpose of coal gas purification and SCP production. The present application first constructs a five-unit closed loop system, achieving the ppb level synchronous removal of five types of key pollutants in coal gas; through the multi-unit synergistic mechanism, the purification efficiency is improved by more than 20%, the energy consumption is reduced by 40%, the resource utilization efficiency is greatly increased, the resource recovery yield reaches 45%, and the benign cycle of full coverage of purification cost and profit is realized.

Description

Technical Field

[0001] This invention relates to the field of deep purification and resource utilization of coal gas, and particularly to a coal gas fermentation-level ultra-deep purification system and method based on pyrolysis-precise screening-flow-directional control. Specifically, it relates to a coal gas fermentation-level ultra-deep purification system and method based on cross-media synergistic pyrolysis-intelligent adaptive screening-precise control of metabolic flow-full-chain resource recovery-digital twin traceability. It is applicable to the fermentation-level purification treatment of various coal gases such as coking coal gas, blast furnace gas, and biomass gasification gas, and is especially suitable for scenarios with stringent requirements for the purity of raw gas, such as high-end ethanol fermentation, methane fermentation, and microbial syngas fermentation. Background Technology

[0002] Coal gas, an important secondary energy source and chemical feedstock produced during coal gasification and coking processes, has a complex composition. Besides effective components such as CO, H2, and CH4, it also contains harmful impurities like H2S, COS, NH3, and HCN, as well as pollutants such as tar mist and particulate matter. With increasingly stringent national environmental policies, especially the rising requirements for green production under the dual-carbon goals, and the stringent ppb-level purity requirements for coal gas in downstream applications such as ethanol fermentation, the importance of coal gas purification technology is becoming increasingly prominent.

[0003] Currently, various coal gas purification technologies have been developed in the industry, mainly including traditional processes such as wet desulfurization and adsorption purification, as well as novel single technologies such as plasma pyrolysis, MOF adsorption, and microbial metabolism regulation. These technologies have been applied to some extent in industrial production. However, long-term practical verification has shown that existing coal gas purification technologies generally suffer from four core bottlenecks, and to date, no single technology has been able to overcome all of these bottlenecks simultaneously. This severely limits the efficient, green, and high-value-added utilization of coal gas, as detailed below:

[0004] Firstly, the purification depth is insufficient and the targeting is poor. Traditional wet desulfurization processes (such as ammonia water method and MEA method) are currently widely used sulfide removal technologies, but their removal rate of sulfides such as H2S and COS in coal gas can only reach 85%-95%, which is far from meeting the ppb-level purification requirements of high-end application scenarios such as coal gas fermentation. Although adsorption methods (such as activated carbon adsorption and molecular sieve adsorption) can be used to remove trace impurities, these methods have low selectivity for the adsorption of trace amounts of NH3 and HCN, and are easily affected by inert components or effective components such as CO2 and CH4 in coal gas with higher content, resulting in unstable adsorption effect. Moreover, the adsorbent needs to be replaced frequently after it reaches saturation, which not only increases the workload of operation and maintenance, but also significantly increases the operation and maintenance cost, making it difficult to achieve long-term stable operation.

[0005] Secondly, resource waste and secondary pollution coexist. The core design of existing coal gas purification technologies is mostly focused on pollutant removal, failing to achieve targeted resource utilization of pollutants, resulting in a serious waste of valuable resources. Specifically, sulfides in coal gas are mostly emitted as low-value waste residue and waste liquid after treatment, failing to achieve the recovery and reuse of sulfur resources; small-molecule organic matter in coal gas is mostly treated by direct incineration, failing to be converted into high-value-added products. At the same time, some purification processes generate secondary pollutants such as sulfur-containing wastewater and waste adsorbents during operation. If not properly treated, these can easily lead to secondary pollution problems, which is inconsistent with the development concept of green production.

[0006] Third, the system's adaptability and stability are weak. Industrial production produces diverse types of coal gas, with significant differences in composition between different types. For example, coking gas contains high concentrations of tar mist, blast furnace gas contains high concentrations of CO, and other types of coal gas may also exhibit large flow fluctuations and complex pollutant compositions. Existing coal gas purification technologies are mostly designed for single operating conditions, only adaptable to the purification needs of specific types and compositions of coal gas. When the coal gas flow rate and pollutant concentration fluctuate by more than ±10%, the purification efficiency of the system will decrease by more than 10%, making it difficult to adapt to the actual operating conditions of frequent fluctuations in coal gas composition and flow rate in industrial production, resulting in poor system operational stability.

[0007] Fourth, there is a lack of full-process traceability and green certification support. The greening and decarbonization of industrial production is an inevitable trend, and green production certification has become an important prerequisite for high-end chemical products to enter the market. However, existing coal gas purification systems lack precise carbon footprint measurement and full-process traceability mechanisms, making it impossible to accurately calculate carbon emissions during the purification process and achieve full-process green traceability. This results in downstream products such as coal gas fermentation products failing to meet green production certification requirements, severely restricting their access to the high-end market and hindering the high-quality development of downstream coal gas industries.

[0008] Furthermore, the application of existing novel purification technologies also has significant limitations. While novel technologies such as plasma pyrolysis, MOF adsorption, and microbial metabolic regulation have certain advantages in individual purification stages, these technologies are currently mostly used independently, failing to form a complete closed-loop purification system encompassing pyrolysis, sieving, conversion, recovery, and traceability. Simultaneously, the synergistic coupling issues between various technological units have not been effectively resolved. For example, plasma pyrolysis products can adversely affect subsequent sieving and microbial metabolic processes, and the regeneration process of the sieving membrane lacks effective linkage with the resource recovery process. This prevents the purification effects of various technologies from achieving synergistic effects, making it difficult to achieve the unified goals of ultra-deep purification, low energy consumption, and resource recovery, and failing to fundamentally address the core pain points of existing coal gas purification technologies.

[0009] In summary, the existing coal gas purification technologies suffer from problems such as insufficient purification depth, low resource utilization, poor system stability, lack of green traceability support, and poor technological synergy. These issues have become key factors restricting the efficient purification and green utilization of coal gas and the high-quality development of downstream industries. Therefore, developing a coal gas purification technology that can simultaneously overcome the above bottlenecks and achieve multi-objective synergy has significant practical significance and industrial application value. Summary of the Invention

[0010] To address the aforementioned problems, this invention relates to a coal gas fermentation-level ultra-deep purification system and method based on pyrolysis-precision screening-flow-directed control.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0012] A method for ultra-deep purification of coal gas at the fermentation stage based on pyrolysis-precision screening-flow-directed control, the method comprising the following specific steps:

[0013] Gradient composite photocatalytic materials are added into a bipolar nanosecond pulsed plasma generator and activated using high-energy electrons.

[0014] The activated gradient composite photocatalytic material, together with the dust-removed and cooled coal gas to be treated, enters the gradient-doped photocatalytic reaction bed to carry out the cracking reaction to remove H2S, COS and tar mist;

[0015] The pyrolysis products are fed into a supercritical CO2 fluid circulation-heat exchange integrated system for supercritical extraction to further remove H2S.

[0016] After extraction, the gas enters the membrane module of the supramolecular biomimetic MOFs intelligent adaptive sieving unit at a speed of 0.5~2 m / s for precise sieving. During the sieving process, the residual concentrations of NH3 and HCN in the gas after sieving at the outlet of the membrane module are monitored by a trace pollutant-specific sensing module to achieve ppb-level precise sieving. Based on the residual concentration data, the intelligent adjustment device for the number of membrane stacking layers is used to adjust the number of composite biomimetic membrane stacking layers in the module and control the adsorption and regeneration speed of the adsorption-regeneration linkage system.

[0017] After screening, the coal gas enters the partitioned co-culture reaction tank of the PN / A-Candida utilis metabolic flow precision control unit. The small molecule organic matter and ammonia nitrogen remaining in the coal gas are subjected to anaerobic, microaerobic and aerobic treatment in sequence to degrade pollutants and synthesize SCP. The final purified gas discharged after aerobic treatment is introduced into the fermentation system, and the traceability code is provided to downstream users simultaneously.

[0018] After the PN / A-Candida utilis metabolic flow precise control unit is completed, the effluent from the aerobic zone enters the desulfurization tower of the all-element graded resource recovery unit to remove moisture, and then enters the sulfide catalytic conversion device to be directionally catalytically converted into elemental sulfur. It is then purified by the supercritical CO2 purification and circulation device. In the supercritical CO2 purification and circulation device, it undergoes depressurization desorption, activated carbon adsorption to remove impurities, condensation liquefaction and pressurization and heating. The purified elemental sulfur is then used by the SCP refining system to be washed, spray dried, screened and sterilized by ultraviolet irradiation in sequence to obtain SCP as feed raw material.

[0019] The PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation employs a random forest algorithm for parameter prediction and intelligent regulation. During application, the multi-dimensional data acquisition module receives data from the online pollutant concentration monitoring and feedback module in the supercritical CO2 fluid circulation-heat exchange integrated system, the trace pollutant-specific sensing module in the supramolecular biomimetic MOFs intelligent adaptive sieving unit, the metabolic flow monitoring sensor in the PN / A-Candida utilis metabolic flow precision regulation unit, and the resource purity online detection module in the all-element graded resource recovery unit. This data is then transmitted to the ANSYS Fluent+Python coupled digital twin model for processing. After processing, the data is stored in the consortium blockchain traceability system and then enters the intelligent decision control module to make decisions. This intelligent decision control module controls various adaptive control valve groups, the intelligent membrane stacking layer number adjustment device, the adsorption-regeneration linkage system, the nutrient salt precision dosing system, and the microbial community activity regulation module via signal connections. After making a decision, the intelligent decision control module adjusts and controls each unit.

[0020] Furthermore, the gradient composite photocatalytic material is a Ti substrate with a bottom layer thickness of 5 mm. 0.8 Fe 0.2 O2, Ti with a middle layer thickness of 3mm 0.7 Cu 0.3 O2 and Ti with a top layer thickness of 2mm 0.6 Zn 0.4 O2.

[0021] Furthermore, the bipolar nanosecond pulsed plasma generator has a pulse width of 5~50ns and a peak voltage of 10~30kV.

[0022] Furthermore, the temperature of the gradient-doped photocatalytic reaction bed is 31.1~40℃, and the gas phase residence time is 2.5~8s;

[0023] The supercritical CO2 fluid in the supercritical CO2 fluid circulation-heat exchange integrated system is controlled at a critical temperature of 31.1~40℃ and a pressure of 7.38~8.0MPa.

[0024] The flow rate of the extracted coal gas entering the supramolecular biomimetic MOFs intelligent adaptive sieving unit is 0.5~2m / s.

[0025] Furthermore, during the screening process, when the concentrations of NH3 and HCN are found to be excessive, the PLC intelligent control system controls the intelligent adjustment device for the number of membrane stacking layers to automatically increase the number of composite biomimetic membrane stacking layers in the module, while reducing the gas flow rate of the extraction gas entering the membrane module to prolong the reaction residence time.

[0026] When the concentration is detected to be far below the threshold, the intelligent adjustment device for controlling the number of membrane stacking layers automatically reduces the number of composite biomimetic membrane stacking layers in the module, while appropriately increasing the gas flow rate of the extracted gas entering the membrane module.

[0027] When the residual concentrations of NH3 and HCN in the screened gas exceed the set safety thresholds, the PLC intelligent control system determines that the currently operating membrane stack module is close to adsorption saturation and needs to enter the regeneration process. The intelligent adjustment device for the number of membrane stack layers will physically remove the composite bionic membrane determined to be saturated from the main airflow or switch it through a valve to remove it from the main purification channel and enter the closed regeneration chamber of the adsorption-regeneration linkage system. At the same time, the PLC intelligent control system issues a command to start the adsorption-regeneration linkage system, switch the gas path valves and start the heating device to purge and desorb pollutants with hot air, and then heat the inert carrier gas to a specific temperature. The resulting hot airflow passes in reverse through the composite bionic membrane. After the hot purge, or for pollutants with poor thermal stability, the adsorption-regeneration linkage system injects CO2 into the regeneration chamber and pressurizes and heats it to a supercritical state for supercritical cleaning.

[0028] After the regeneration process is completed, a cold, dry, inert gas is introduced to rapidly cool the composite biomimetic membrane to room temperature, preventing high temperatures from damaging organic components such as chitosan. At the same time, the PLC intelligent control system may perform a brief self-check to confirm that the membrane has regained its activity. The intelligent adjustment device for the number of membrane stacking layers will reinsert the regenerated composite biomimetic membrane into the working position, or switch it back to the main gas flow through a valve to enter the next adsorption cycle.

[0029] Furthermore, the carbon-to-nitrogen ratio of each zone in the partitioned co-culture reactor is 3:1, the dissolved oxygen concentration in the anaerobic zone is ≤0.1mg / L, the dissolved oxygen concentration in the microaerobic zone is 0.2~0.5mg / L, the dissolved oxygen concentration in the aerobic zone is 1.0~1.5mg / L, the temperature in each zone is 28~32℃, and the pH value is 7.2~7.8.

[0030] During the treatment process, metabolic flow monitoring sensors monitor the metabolic activity, substrate consumption rate, and product (SCP) generation rate of microorganisms in the reaction tank in real time. Based on the C / N / P nutrient ratio required for microbial growth and the substrate consumption feedback from the metabolic flow monitoring sensors, the frequency and dosage of nutrient salt dosing pumps are dynamically adjusted to maintain the ratio of PN / A bacteria to Candida utilis at 3:1, ensuring that the microorganisms are in optimal growth condition. Simultaneously, based on the activity status and reaction rate of microorganisms in each zone, the power and frequency of ultrasound in the microbial activity regulation module are adjusted in real time. When the metabolic flow monitoring sensors detect a decrease in reaction rate, the PLC intelligent control system automatically optimizes the ultrasound parameters by controlling the microbial activity regulation module.

[0031] Furthermore, the catalytic conversion unit for sulfide catalytic conversion has a catalytic conversion temperature of 300~350℃, a pressure of 0.3~0.5MPa, and a catalyst of Co-Mo / Al2O3;

[0032] The spray drying temperature in the SCP refining system is 120~150℃, the particle size of the sieve is 100~200μm, and the UV sterilization dose is 25~30mJ / cm. 2 .

[0033] Furthermore, the PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation uses ANSYS Fluent+Python to couple digital twin models to intelligently regulate system parameters, while recording carbon footprint data and generating unique traceability codes through a consortium blockchain traceability system.

[0034] The ANSYS Fluent+Python coupled digital twin model and consortium blockchain traceability system are detailed below:

[0035] Data Acquisition and Simulation:

[0036] The system uses ANSYS Fluent software to perform fluid dynamics simulation of the entire purification process;

[0037] On-site sensors collect real-time data on gas flow, temperature, pressure, and pollutant concentration, and input the data into the Fluent model for real-time calibration, establishing a "digital twin" synchronized with the physical entity;

[0038] Intelligent decision-making:

[0039] The Python script serves as the core of the control logic, reading the simulation results and real-time sensor data from the digital twin model.

[0040] The Python algorithm dynamically adjusts the operating parameters of the three cascaded units based on the type and concentration of pollutants.

[0041] When a high tar content is detected, Python will automatically increase the peak voltage of the plasma generator;

[0042] When residual ammonia is detected, Python will adjust the light intensity or gas residence time of the photocatalytic reaction bed.

[0043] When the system temperature is too high, Python will instruct the supercritical CO2 system to increase the circulation flow rate to enhance heat exchange and cooling.

[0044] Implementation and Feedback:

[0045] Control commands issued by Python are sent to various hardware devices via the PLC;

[0046] At the same time, the system uploads all operational data to the blockchain to achieve an immutable record of the carbon footprint, which can be used for subsequent carbon trading accounting or environmental compliance audits.

[0047] Closed-loop control:

[0048] The trace pollutant sensing module at the outlet continuously monitors the purification effect; when the outlet concentration exceeds the standard, the system will immediately trigger an alarm and automatically backtrack to adjust the parameters of the preceding units, forming a fully closed-loop intelligent control process of monitoring, simulation, decision-making, execution, and re-monitoring.

[0049] A coal gas fermentation-level ultra-deep purification system based on pyrolysis-precision screening-flow-directed control, the system being used in the above method;

[0050] The system includes a cross-media collaborative pyrolysis unit, a supramolecular biomimetic MOFs intelligent adaptation sieving unit, a PN / A-candida utilis metabolic flow precise regulation unit, and a full-element graded resource recovery unit, which are connected in series through adaptive control valve groups. It also includes a PLC intelligent control system that communicates bidirectionally with each unit, which is a digital twin-blockchain carbon footprint traceability and intelligent regulation system. The PLC intelligent control system is signal-connected to each adaptive control valve group.

[0051] The cross-media synergistic pyrolysis unit includes a bipolar nanosecond pulsed plasma generator, a gradient-doped photocatalytic reaction bed, and a supercritical CO2 fluid circulation-heat exchange integrated system connected in series. The outlet of the supercritical CO2 fluid circulation-heat exchange integrated system is also connected to the inlet of the supramolecular biomimetic MOFs intelligent adaptive sieving unit through an adaptive control valve group.

[0052] The supramolecular biomimetic MOFs intelligent adaptive sieving unit includes a membrane module, an intelligent adjustment device for the number of membrane stacks, an adsorption-regeneration linkage system, and a trace pollutant-specific sensing module. The membrane module is composed of at least one Zn-MOF-74@cellulose-chitosan composite biomimetic membrane stacked in parallel, and the membrane module is vertically arranged in the central core area of ​​the sieving unit. The intelligent adjustment device for the number of membrane stacks is directly connected to the membrane module, and the adjustment device is assembled on the top of the membrane module. Its output end is fixedly connected to the top of the membrane module and is powered by a drive motor. The adsorption-regeneration linkage system forms a closed loop connection with the membrane module. It is arranged around the outside of the membrane module and is connected to the inlet and outlet of the membrane module. The trace pollutant-specific sensing module is fixedly installed on the outlet side of the membrane module, with its detection probe facing the discharge end of the membrane module. The trace pollutant-specific sensing module is connected to the PLC intelligent control system. The PLC intelligent control system is also connected to the intelligent adjustment device for the number of membrane stacks and the adsorption-regeneration linkage system.

[0053] The PN / A-Candida utilis metabolic flow precision control unit includes a partitioned co-culture reaction tank. The tank is divided into three independent and interconnected reaction zones: an anaerobic zone, a microaerobic zone, and an aerobic zone, which are arranged in sequence by partitions. The partitions have reserved connection ports. The inlet end of the anaerobic zone is also connected to the outlet end of the membrane module.

[0054] The PN / A-Candida utilis metabolic flow precision control unit also includes a nutrient salt precision dosing system. Its discharge end is connected to the anaerobic zone, microaerobic zone and aerobic zone inside the reaction tank through a conveying pipeline, and the outlet end of the conveying pipeline extends into each zone.

[0055] The anaerobic, microaerobic, and aerobic zones are equipped with metabolic flow monitoring sensors and microbial activity regulation modules. The metabolic flow monitoring sensors are installed on the inner side of the pool wall of each zone, and the detection probes extend to the material reaction area of ​​each zone. The signal output terminals of the metabolic flow monitoring sensors are connected to the metering pump of the nutrient salt precision dosing system and the microbial activity regulation module through the PLC intelligent control system.

[0056] The microbial community activity regulation module is installed on the outside of each zone, and the ultrasonic transmitter is fixedly connected to the wall of each zone. The control end of the microbial community activity regulation module establishes a signal connection with the metabolic flow monitoring sensor through the PLC intelligent control system.

[0057] The all-element graded resource recovery unit includes a desulfurization tower, a sulfide catalytic conversion device, a supercritical CO2 purification and circulation device, an SCP refining system, and an online resource purity detection module;

[0058] The desulfurization tower is located at the front of the unit. Its inlet is connected to the outlet of the aerobic tank, and its outlet is connected to the inlet of the sulfide catalytic conversion device. The outlet of the sulfide catalytic conversion device is connected to the inlet of the supercritical CO2 purification and circulation device. The SCP purification system is arranged in parallel behind the supercritical CO2 purification and circulation device and is connected to the outlet of the supercritical CO2 purification and circulation device.

[0059] The online resource purity detection module is connected to the discharge end of the sulfide catalytic conversion unit, the supercritical CO2 purification and circulation unit, and the SCP refining system, respectively, and the detection probe corresponds to the discharge end of each unit.

[0060] The PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation includes a multi-dimensional data acquisition module connected by sequential signals, an ANSYS Fluent+Python coupled digital twin model, a consortium blockchain traceability system, and an intelligent decision control module.

[0061] Among them, the multi-dimensional data acquisition module is connected to the pollutant concentration online monitoring and feedback module in the supercritical CO2 fluid circulation-heat exchange integrated system, the trace pollutant specific sensing module in the supramolecular biomimetic MOFs intelligent adaptation sieving unit, the metabolic flow monitoring sensor in the PN / A-Candida utilis metabolic flow precise regulation unit, and the resource purity online detection module in the all-element graded resource recovery unit.

[0062] The intelligent decision control module is connected to each adaptive control valve group, the intelligent adjustment device for the number of membrane stacks, the adsorption-regeneration linkage system, the nutrient salt precision dosing system, and the microbial activity regulation module.

[0063] Furthermore, in the cross-medium synergistic pyrolysis unit, an adaptive control valve group is installed between the three devices: the bipolar nanosecond pulse plasma generator, the gradient-doped photocatalytic reaction bed, and the supercritical CO2 fluid circulation-heat exchange integrated system. The adaptive control valve group is connected to the PLC intelligent control system. At the same time, the supercritical CO2 fluid circulation-heat exchange integrated system is also equipped with a pollutant concentration online monitoring and feedback module, which is also connected to the PLC intelligent control system. The PLC intelligent control system is also connected to the supercritical CO2 fluid circulation-heat exchange integrated system.

[0064] The beneficial effects of the coal gas fermentation-level ultra-deep purification system and method based on pyrolysis-precision sieving-flow-directed control of the present invention are as follows:

[0065] This invention significantly outperforms existing technologies in all core indicators of gas purification and resource recovery. Specifically, the H2S removal rate is ≥99.95% and the NH3 removal rate is ≥99.9%, far exceeding wet desulfurization combined with activated carbon adsorption technology (H2S removal rate 85-95%, NH3 removal rate 70-80%) and single MOF adsorption technology (H2S removal rate 90-96%, NH3 removal rate 85-90%). The final purified gas purity reaches the ppb level (H2S ≤0.05 mg / m³). 3 NH3 ≤ 0.1 mg / m³ 3 This is superior to the sub-ppb level of adsorption by single MOFs (H2S≥0.5mg / m³). 3 NH3 ≥ 1 mg / m³ 3 ) and wet desulfurization combined with activated carbon adsorption at the mg / m³ level (H2S≥5mg / m³) 3 NH3 ≥ 10 mg / m³ 3 Regarding resource recovery, this invention can achieve the resource recovery of industrial-grade sulfur (99.9%) and SCP feed ingredients (60% protein), with a resource recovery rate of ≥45%, while the two existing technologies have no resource recovery capability and a rate of 0; in terms of system energy consumption, this invention is ≤0.8kWh / Nm 3 The efficiency is lower than that of wet desulfurization combined with activated carbon adsorption (≥1.33 kWh / Nm³). 3 ) and single MOF adsorption (≥1.1kWh / Nm 3 Under operating conditions with a flow rate fluctuation of ±20%, the purification efficiency of this invention fluctuates by ≤2%, which is far superior to the two existing technologies (≥15% and ≥10%, respectively). At the same time, this invention has the ability to trace the carbon footprint of the entire process, which is not available in existing technologies.

[0066] This invention achieves several technological breakthroughs and innovations. It is the first to construct a five-unit closed-loop system, overcoming the shortcomings of existing technologies that are single-function and lack coordination. It achieves simultaneous removal of five key pollutants in coal gas at the ppb level, filling a gap in fermentation-grade coal gas purification technology. Through a multi-unit collaborative mechanism, the overall purification effect far exceeds that of simple superposition, increasing purification efficiency by over 20% and reducing energy consumption by 40%. Resource utilization efficiency is significantly improved, with a resource recovery rate of 45%, achieving a virtuous cycle of full coverage of purification costs and profitability. It is the first to integrate digital twin and blockchain technologies to construct a green traceability system, supporting green certification and contributing to a 10-15% product premium. Simultaneously, it possesses extreme stability and adaptability, with purification efficiency fluctuations of ≤2% under extreme operating conditions, and can be adapted to more than three types of coal gas, significantly lowering the application threshold.

[0067] The gradient composite photocatalytic material, Zn-MOF-74@cellulose-chitosan biomimetic membrane, and partitioned co-culture reaction tank used in this invention are all specifically designed and have been experimentally verified to have superior performance.

[0068] This invention fills a gap in existing technologies by adding three major functions: targeted resource utilization, intelligent adaptation, and carbon footprint traceability. This invention clearly defines key technical parameters, making it highly repeatable and practical. Attached Figure Description

[0069] Figure 1 This is a process flow diagram from Embodiment 1 of the present invention. Detailed Implementation

[0070] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0071] Example 1: A Coal Gas Fermentation-Level Ultra-Deep Purification System and Method Based on Pyrolysis-Precision Sieving-Flow Directional Control

[0072] This embodiment is a coal gas fermentation-level ultra-deep purification system based on pyrolysis-precision screening-flow-directed regulation. It includes a cross-media collaborative pyrolysis unit, a supramolecular biomimetic MOFs intelligent adaptive screening unit, a PN / A-Candida utilis metabolic flow precision regulation unit, and a full-element graded resource recovery unit, which are connected in series through adaptive control valve groups. It also includes a PLC intelligent control system (model: S7-1500) that communicates bidirectionally with each unit, using a digital twin-blockchain carbon footprint traceability and intelligent regulation. The PLC intelligent control system is signal-connected to each adaptive control valve group. Each unit is linked through the adaptive control valve group and the PLC intelligent control system, forming a closed-loop system of pyrolysis, screening, conversion, recovery, and regulation.

[0073] The cross-medium synergistic pyrolysis unit (with a newly added synergistic activation mechanism and intelligent regulation) includes a bipolar nanosecond pulsed plasma generator (model: NP-30kV, output power 5kW) connected in series, and a gradient-doped photocatalytic reaction bed (size: Φ500mm×2000mm, material: 316L stainless steel, pressure resistance 0.1-1.0MPa, temperature resistance 2080℃). The gradient-doped photocatalytic reaction bed is equipped with upper and lower gas distributors. The gradient composite photocatalytic material is fixed between the two distributors in the form of modular packing, with a 10-15% bed expansion space reserved to prevent gas deviation. The system features a short-circuit, high-flow-rate supercritical CO2 fluid circulation system. Operating control parameters include a reaction temperature of 31.1~40℃, coordinated with the supercritical CO2 fluid temperature to reduce system heat exchange energy consumption; a gas phase residence time of 2.58s, which can be adaptively adjusted according to the inlet gas pollutant concentration to ensure H2S, COS, and tar mist cracking efficiency ≥99.5%. The gradient-doped photocatalytic reactor is equipped with online temperature and pressure monitoring instruments, with data uploaded in real-time to the PLC intelligent control system for closed-loop control of operating parameters. It also includes a supercritical CO2 fluid circulation-heat exchange integrated system (circulation pump model: PCO2-50, flow rate 50m³ / h). 3 The outlet of the supercritical CO2 fluid circulation-heat exchange integrated system is connected to the inlet of the supramolecular biomimetic MOFs intelligent adaptive sieving unit via an adaptive control valve group. Furthermore, an adaptive control valve group is installed between the bipolar nanosecond pulsed plasma generator, the gradient-doped photocatalytic reaction bed, and the supercritical CO2 fluid circulation-heat exchange integrated system. This adaptive control valve group is connected to the PLC intelligent control system. Additionally, the supercritical CO2 fluid circulation-heat exchange integrated system includes an online pollutant concentration monitoring and feedback module (sensor model: GAS-300), which is also connected to the PLC intelligent control system. The PLC intelligent control system is also connected to the supercritical CO2 fluid circulation-heat exchange integrated system to control the CO2 circulation rate. The online pollutant concentration monitoring and feedback module adjusts the CO2 circulation rate within the supercritical CO2 fluid circulation-heat exchange integrated system by detecting the H2S concentration.

[0074] The gradient-doped photocatalytic reaction bed is arranged from top to bottom as follows: inlet end, upper gas distributor, catalytic packing fixing chamber, and lower gas distributor. The gradient-doped photocatalytic reaction bed has an outlet end on one side. The shell is equipped with a heat-insulating jacket and is connected to the heat exchange pipeline of the supercritical CO2 fluid circulation-heat exchange integrated system to achieve coordinated control of the reaction temperature. The inlet end is connected to the outlet of the bipolar nanosecond pulse plasma generator through an adaptive control valve group, and the outlet end is connected to the inlet of the supercritical CO2 fluid circulation-heat exchange integrated system through an adaptive control valve group. The monitoring instruments of the equipment are all connected to the PLC intelligent control system.

[0075] The supramolecular biomimetic MOFs intelligent adaptive sieving unit (with added dynamic response and regeneration linkage) includes a membrane module, an intelligent adjustment device for the number of membrane stack layers (drive motor model: SM-20), an adsorption-regeneration linkage system (model: ZS-200, core components include: modular closed regeneration chamber, programmable gas path switching valve group, heating / cooling temperature control module, supercritical CO2 injection branch, inert carrier gas purging branch, and exhaust gas pretreatment module; this system forms a closed-loop linkage with the membrane module and PLC intelligent control system, enabling non-stop online regeneration of a single membrane without interrupting the overall purification process), and a trace pollutant specific sensing module (detection limit 0.01ppb, model: MS-100).

[0076] The membrane module is composed of at least one Zn-MOF-74@cellulose-chitosan composite biomimetic membrane (single membrane size: Φ450mm×20mm) stacked in parallel. Each Zn-MOF-74@cellulose-chitosan composite biomimetic membrane is sealed and fixed by a 316L stainless steel frame to form an independent standardized membrane unit. The single membrane size is Φ450mm×20mm, and the frame has reserved guide rail slots and sealing grooves. The main body of the membrane module includes a vertical shell, vertical parallel guide rails, standardized membrane units, an intelligent adjustment device for the number of membrane stacking layers, and inlet and outlet flow channels. The inlet and outlet of the shell are equipped with rectification structures to ensure uniform gas distribution. The standardized diaphragm unit is installed on all diaphragm surfaces. The guide rail spacing matches the diaphragm unit frame. When adding a diaphragm unit, simply insert it vertically along the guide rail to complete the installation of a single diaphragm. A 5-8mm uniform airflow channel is reserved between adjacent diaphragms to ensure that the gas flows evenly across the diaphragm surface without any flow deviation or dead zones. The drive motor of the intelligent diaphragm stacking layer adjustment device is linked with the guide rail transmission structure. It can automatically complete the insertion, removal, and layer adjustment of diaphragms through PLC commands without the need for manual disassembly. When replacing or adding diaphragms, simply pull the diaphragm to be replaced out of the guide rail and replace it with a new standardized diaphragm unit. The operation is convenient and the maintenance cost is low.

[0077] The inlet of the supramolecular biomimetic MOFs intelligent adaptive sieving unit is connected to the outlet of the supercritical CO2 fluid circulation-heat exchange integrated system through an adaptive control valve group. The outlet is connected to the inlet of the PN / A-Candida utilis metabolic flow precision control unit. The sensing module, regulating device, and regeneration system of the membrane module are all connected to the PLC intelligent control system.

[0078] The membrane module is vertically arranged in the central core area of ​​the screening unit, following a conventional placement method. As the core carrier for material screening and trace pollutant adsorption, its arrangement and position ensure that the material flows evenly across the membrane surface, maximizing screening and adsorption efficiency. The composite biomimetic membrane introduces chitosan (10%-15% by mass) into the Zn-MOF-74 framework. Through a Schiff base reaction, amino (-NH2) and aldehyde (-CHO) groups are crosslinked to form a three-dimensional network structure of MOFs-cellulose-chitosan. The tensile strength is ≥15MPa, an 80% improvement over pure MOF membranes. The adsorption selectivity coefficient for NH3 / CO2 is ≥50, and the adsorption selectivity coefficient for HCN / CH4 is ≥45.

[0079] The intelligent adjustment device for the number of membrane stacking layers is directly connected to the membrane module. The adjustment device is assembled on the top of the membrane module, and its output end is fixedly connected to the top of the membrane module. Through the power transmission of the drive motor, the number of stacking layers of the composite biomimetic membrane in the membrane module can be precisely adjusted, thereby adapting to the screening requirements of different materials and realizing intelligent control of screening accuracy. Its position arrangement facilitates power transmission and does not interfere with the material flow and subsequent regeneration operation.

[0080] The adsorption-regeneration linkage system forms a closed-loop connection with the membrane module and is the core system for realizing online switching and composite regeneration. It is arranged around the outside of the membrane module and is connected to the inlet and outlet of the membrane module. It can realize the adsorption and screening of materials when they flow through the membrane module, and can also regenerate the saturated membrane module through a modular switching mechanism without stopping the overall screening operation after the membrane module reaches adsorption saturation. It realizes the coordinated linkage of adsorption and regeneration. Its connection method ensures the smooth flow of materials and regeneration media, and its position arrangement takes into account both linkage efficiency and the compactness of the overall unit structure.

[0081] The trace pollutant specific sensing module is fixedly installed on the outlet side of the membrane module, with its detection probe facing the discharge end of the membrane module. The trace pollutant specific sensing module is connected to the PLC intelligent control system. The PLC intelligent control system is also connected to the membrane stacking layer number intelligent adjustment device and the adsorption-regeneration linkage system.

[0082] The PLC intelligent control system uses a trace pollutant-specific sensing module to detect the content of trace pollutants in the material after screening by the membrane module in real time, thereby determining the adsorption saturation state of the membrane module, controlling the opening and closing degree of the adaptive control valve group at the front end of the supramolecular biomimetic MOFs intelligent adaptation screening unit, controlling the intelligent adjustment device for the number of membrane stacking layers to adjust the number of composite biomimetic membrane stacking layers in the membrane module, and controlling the adsorption and regeneration speed of the adsorption-regeneration linkage system.

[0083] The PN / A-Candida utilis metabolic flow precision control unit (with added community synergistic activation and metabolic pathway optimization) includes a partitioned co-culture reaction tank (size: 3m×2m×1.5m, effective volume 8m³). 3 The partitioned co-cultivation reactor is divided into three independent but interconnected reaction zones—anaerobic, microaerobic, and aerobic—by vertical partitions (anaerobic zone 60%, microaerobic zone 20%, aerobic zone 20%). The partitions have pre-reserved connection ports to ensure orderly material flow and fully mixed-flow water delivery, preventing short-circuiting and enabling segmented control of hydraulic retention time (HRT) (anaerobic zone HRT = 8~12h, microaerobic zone HRT = 4~6h, aerobic zone HRT = 4~6h) to avoid inhibiting microbial metabolism. The inlet of the anaerobic zone is also connected to the outlet of the membrane module. The anaerobic zone is equipped with a water and air distribution system, while the microaerobic and aerobic zones are equipped with aeration systems and online dissolved oxygen monitoring probes.

[0084] The PN / A-Candida utilis metabolic flow precision control unit also includes a conventional nutrient salt precision dosing system (metering pump model: JXM-50), whose outlet end is connected to the anaerobic zone, microaerobic zone and aerobic zone inside the reaction tank through a conveying pipeline, and the outlet end of the conveying pipeline extends into each zone.

[0085] The anaerobic, microaerobic, and aerobic zones are equipped with conventional metabolic flow monitoring sensors (model: MFS-200) and conventional microbial activity regulation modules (embedded low-frequency ultrasonic generator model: US-40). The metabolic flow monitoring sensors are installed on the inner walls of each zone, with the detection probes extending to the material reaction area of ​​each zone to ensure full contact between the probes and the materials. The signal output of the metabolic flow monitoring sensors establishes bidirectional signal connections with the metering pump of the nutrient precision dosing system and the microbial activity regulation module through a PLC intelligent control system. This allows for real-time monitoring of the concentration of key substrates in each zone, simultaneously transmitting the monitoring signals to the nutrient precision dosing system and the microbial activity regulation module, triggering nutrient dosing regulation and microbial activity enhancement operations.

[0086] The microbial community activity regulation module is installed on the outside of each zone, and the ultrasonic transmitter is fixedly connected to the wall of each zone, with the ultrasonic range covering the interior of each zone. The control end of the module establishes a signal connection with the metabolic flow monitoring sensor through the PLC intelligent control system, and can start or adjust the low-frequency ultrasonic parameters according to the metabolic flow monitoring results and the microbial community activity status.

[0087] The all-element graded resource recovery unit (with added graded recovery and purity control) includes a desulfurization tower, a sulfide catalytic conversion device (i.e., catalytic conversion furnace, size: Φ300mm×1500mm, material: Hastelloy, catalyst Co-Mo / Al2O3 loading: 50kg), a conventional supercritical CO2 purification and circulation device (purification column size: Φ200mm×1000mm), a conventional SCP refining system (including a washing device, spray dryer, screening machine and ultraviolet irradiation sterilizer connected in sequence, wherein the spray dryer model: SD-100), and a resource purity online detection module (model: PP-500).

[0088] The desulfurization tower is located at the front end of the unit. Its inlet is connected to the outlet of the aerobic pool, and its outlet is connected to the inlet of the sulfide catalytic conversion device. The outlet of the sulfide catalytic conversion device is connected to the inlet of the supercritical CO2 purification and circulation device. The SCP purification system is arranged in parallel behind the supercritical CO2 purification and circulation device and is connected to the outlet of the supercritical CO2 purification and circulation device.

[0089] The online purity detection module (model PP-500) is connected to the discharge end of the sulfide catalytic conversion unit, the supercritical CO2 purification and circulation unit, and the SCP refining system, respectively, with the detection probe corresponding to the discharge end of each unit; the supercritical CO2 purification and circulation unit forms a closed loop through pipelines to achieve circulating purification.

[0090] All components work together in a coordinated manner. After catalytic conversion, the sulfides are purified in a supercritical fluid processing unit. Then, the SCP is processed by the SCP refining system. The purity detection module monitors the purity of each product in real time to ensure that key indicator requirements are met.

[0091] The digital twin-blockchain carbon footprint traceability and intelligent control PLC intelligent control system (with added intelligent decision-making and traceability enhancement) includes a multi-dimensional data acquisition module (acquiring 20+ parameters, sampling frequency 1 time / second), an ANSYS Fluent+Python coupled digital twin model, a consortium blockchain traceability system (consortium blockchain node server, 8 cores 16G, storage capacity 1TB, number of nodes 5, i.e., 5 units: raw material supply, purification enterprise, testing agency, fermentation enterprise, certification agency), and an intelligent decision control module (i.e., PLC controller, S7-1500, supporting 20 analog inputs).

[0092] The multi-dimensional data acquisition module is connected to the online pollutant concentration monitoring and feedback module in the supercritical CO2 fluid circulation-heat exchange integrated system, the trace pollutant specific sensing module in the supramolecular biomimetic MOFs intelligent adaptive sieving unit, the metabolic flow monitoring sensor in the PN / A-Candida utilis metabolic flow precision control unit, and the resource purity online detection module in the all-element graded resource recovery unit. The multi-dimensional data acquisition module receives data from these units and transmits it to the ANSYS Fluent+Python coupled digital twin model for processing. The processed data is then stored in the consortium blockchain traceability system and subsequently enters the intelligent decision control module to make a decision. The intelligent decision control module is connected to each adaptive control valve group, the intelligent membrane stack number adjustment device, the adsorption-regeneration linkage system, the nutrient salt precision dosing system, and the microbial activity regulation module. After making a decision, the intelligent decision control module adjusts and controls each unit by controlling these components.

[0093] This embodiment describes a method for ultra-deep purification of coal gas at the fermentation stage, based on pyrolysis-precision screening-flow-directed control. Figure 1 As shown, the specific steps include the following:

[0094] Take Ti 0.8 Fe 0.2 O2 (bottom layer, 5mm thickness) - Ti 0.7 Cu 0.3 O2 (middle layer, 3mm thickness) - Ti 0.6 Zn 0.4 A gradient composite photocatalytic material with O2 (top layer, 2mm thickness) was prepared in situ on a 316L stainless steel porous support using multi-target magnetron sputtering. (The gradient composite photocatalytic material was custom-processed by established domestic manufacturers with qualifications in vacuum coating and ceramic catalytic materials, such as Beijing Chuangshi Weina Technology Co., Ltd. and Shenyang Keyi Vacuum Technology Co., Ltd.). The substrate of the gradient composite photocatalytic material used a 316L stainless steel porous support with a porosity ≥40%, ensuring sufficient contact between the gas and the catalytically active sites. After activation by high-energy electron plasma, the photoresponse range was extended to 4... The photocatalytic activity of the gradient-doped photocatalytic material (which has a photocatalytic activity of more than 60% higher than that of a single-doped material) is loaded into a gradient-doped photocatalytic reaction bed in the visible light region of 400~550nm. At the same time, the gradient composite photocatalytic material is added into a bipolar nanosecond pulsed plasma generator. The lattice defects of the gradient composite photocatalytic material are activated by high-energy electrons (energy 5~10eV), so that the photoresponse range is extended to the visible light region (400~550nm). The pulse width of the bipolar nanosecond pulsed plasma generator is 30~50ns and the peak voltage is 10~30kV, preferably 25kV.

[0095] The activated gradient composite photocatalytic material, along with the coal gas to be treated after dust removal and cooling to 30-40°C, enters the gradient-doped photocatalytic reaction bed for pyrolysis to remove H2S, COS, and tar mist. The pollutant pyrolysis efficiency is ≥99.5% (H2S pyrolysis rate ≥99.8%, tar mist pyrolysis rate ≥99.6%). The temperature of the gradient-doped photocatalytic reaction bed is 31.1-40°C (in synergy with the supercritical CO2 fluid temperature), and the gas phase residence time is 2.5-8s (4s in this embodiment).

[0096] The pyrolysis products (such as H2, CO, CH4, etc.) enter a supercritical CO2 fluid circulation-heat exchange integrated system for supercritical extraction to further remove H2S. The supercritical CO2 fluid in the supercritical CO2 fluid circulation-heat exchange integrated system is controlled at a critical temperature of 31.1~40℃ and a pressure of 7.38~8.0MPa (35℃ and 7.8MPa in this embodiment). The PLC system automatically adjusts the circulation velocity of the supercritical CO2 fluid in the supercritical CO2 fluid circulation-heat exchange integrated system to 1~3m / s (2m / s in this embodiment). When the pollutant concentration online monitoring and feedback module detects H2S ≥ 100mg / m³, the system will perform a supercritical extraction. 3 At the same time, the PLC intelligent control system automatically increases the circulation flow rate to ensure that the pyrolysis products quickly leave the reaction zone and avoid secondary polymerization.

[0097] After extraction, the coal gas enters the membrane module of the supramolecular biomimetic MOFs intelligent adaptive sieving unit at a speed of 0.5~2 m / s (0.8 m / s in this example) for precise sieving. During the sieving process, the residual concentrations of NH3 and HCN in the sieved coal gas at the membrane module outlet are monitored by a trace pollutant-specific sensing module, achieving ppb-level precise sieving. Based on this residual concentration data, the number of composite biomimetic membrane stacking layers in the module is adjusted by an intelligent adjustment device (generally 3~8 layers, 8 layers in this example), and the adsorption and regeneration rates of the adsorption-regeneration linkage system are controlled. The supramolecular biomimetic MOFs intelligent adaptive sieving unit achieves a sieving accuracy of 0.01 ppb, with an NH3 adsorption capacity ≥180 mg / g, an HCN adsorption capacity ≥160 mg / g, and a rejection rate of ≤0.5% for effective components such as CO2 and CH4.

[0098] During the screening process, the residual concentrations of NH3 and HCN in the screened gas at the outlet of the membrane module are monitored by a trace pollutant-specific sensing module to achieve precise screening at the ppb level. Based on the residual concentration data, the intelligent adjustment device for the number of membrane stacking layers is used to adjust the number of composite biomimetic membrane stacking layers in the membrane module and control the adsorption and regeneration speed of the adsorption-regeneration linkage system. The regeneration cycle of the adsorption-regeneration linkage system is 12 hours (repeated by 12 minutes of thermal regeneration and 6 minutes of CO2 backflushing).

[0099] When the concentrations of NH3 and HCN are detected to exceed the standard (above the set threshold, i.e., NH3 ≥ 0.5 mg / m³), 3 When the concentration is detected to be significantly lower than the threshold (i.e., NH3 ≤ 0.1 mg / m³), the PLC intelligent control system automatically increases the number of composite biomimetic membrane stacking layers in the module (by 2-3 layers) to increase the contact area and adsorption / reaction depth. Simultaneously, the gas flow rate after extraction entering the membrane module is reduced to prolong the reaction residence time, ensuring precise sieving at the ppb level. 3 When the membrane stacking layer number adjustment device is activated, it automatically reduces the number of composite biomimetic membrane stacking layers in the module (reducing by 1-2 layers) to lower system pressure drop and energy consumption. Simultaneously, it appropriately increases the gas flow rate after extraction entering the membrane module to improve processing efficiency. When the membrane module is determined to be saturated with adsorption, it automatically switches to the regeneration program, achieving membrane regeneration through hot air purging and supercritical CO2 cleaning. After regeneration, the membrane adsorption capacity decreases by ≤5%.

[0100] The adsorption-regeneration linkage system is designed to efficiently revitalize saturated membrane modules through modular switching, while ensuring overall purification continuity.

[0101] When the residual concentrations of NH3 and HCN in the sieved gas exceed the set safety threshold (for example, NH3 concentration exceeding 0.1 mg / m³ for 5 consecutive minutes), 3(If the background value is low or shows an upward trend), the PLC intelligent control system determines that the currently operating membrane stack module is close to adsorption saturation and needs to enter the regeneration process. The intelligent adjustment device for the number of membrane stack layers will physically remove the composite biomimetic membrane determined to be saturated from the main airflow or switch it through a valve to remove it from the main purification channel and enter the closed regeneration chamber of the adsorption-regeneration linkage system. At the same time, the PLC intelligent control system issues a command to start the adsorption-regeneration linkage system, switch the gas path valves and start the heating device. 80~120°C hot air is used to purge (10~15min) to desorb 80% of the pollutants. Then, an inert carrier gas (such as nitrogen) is heated to a specific temperature (e.g., 50~80°C, depending on the thermal stability of Zn-MOF-74). The resulting hot airflow passes in the opposite direction through the composite biomimetic membrane (backflushing). The heat energy breaks the binding force between NH3 / HCN molecules and the active sites of MOFs, blowing out the adsorbed pollutants, thereby removing most of the volatile and moderately bound pollutants. After thermal purging, or for pollutants with poor thermal stability, the adsorption-regeneration linkage system injects CO2 into the regeneration chamber and pressurizes and heats it to a supercritical state (critical point approximately 31.1℃, 7.38MPa) for supercritical cleaning (5~8min), desorbing the remaining 20% ​​of pollutants. The regeneration energy consumption is reduced by 60% compared to single thermal regeneration. Supercritical CO2 can penetrate deep into the microporous structure of MOFs, dissolving and carrying away residual heavy molecules or polymers that are difficult to remove by thermal purging, preventing membrane pore blockage, restoring the membrane's initial porosity and flux, and extending the membrane's service life.

[0102] After the regeneration process is complete, a cold, dry, inert gas is introduced to rapidly cool the composite biomimetic membrane to room temperature, preventing damage to organic components such as chitosan from high temperatures. Simultaneously, the PLC intelligent control system may perform a brief self-check (such as measuring air permeability) to confirm that the membrane has regained its activity. The intelligent membrane stacking layer adjustment device reinserts the regenerated composite biomimetic membrane into its working position, or switches it back to the main gas flow via a valve, allowing it to enter the next adsorption cycle. The membrane adsorption capacity decreases by ≤5% after regeneration, and the number of regeneration cycles is ≥80.

[0103] After screening, the coal gas enters the partitioned co-culture reaction tank of the PN / A-Candida utilis metabolic flow precision control unit. The small molecule organic matter and ammonia nitrogen remaining in the coal gas are subjected to anaerobic, microaerobic and aerobic treatment in sequence to degrade pollutants and synthesize SCP. After treatment, the product has a COD removal rate of ≥98%, an ammonia nitrogen removal rate of ≥99%, and an SCP protein content of ≥60%. The anaerobic zone has a heating time of 10 hours, the microaerobic zone has a heating time of 5 hours, and the aerobic zone has a heating time of 5 hours. The carbon-to-nitrogen ratio (C / N) of each zone is 3:1. The dissolved oxygen concentration in the anaerobic zone is ≤0.1 mg / L, the dissolved oxygen concentration in the microaerobic zone is 0.2~0.5 mg / L, and the dissolved oxygen concentration in the aerobic zone is 1.0~1.5 mg / L. The temperature of each zone is 28~32℃, and the pH value is 7.2~7.8 (in this implementation, the dissolved oxygen concentration is 0.08 mg / L in the anaerobic zone, 0.3 mg / L in the microaerobic zone, and 1.2 mg / L in the aerobic zone. The temperature of each zone is 30℃, the pH value is 7.5, the ultrasonic frequency is 30 kHz, and the power is 80 W).

[0104] During the treatment process, metabolic flow monitoring sensors continuously monitor the metabolic activity of microorganisms, the consumption rate of substrates (small molecule organic matter and ammonia nitrogen), and the production rate of byproducts (SCP) in the reaction tank. Based on the C / N / P nutrient ratios required for microbial growth, and combined with the substrate consumption data (key substrates such as methanol, acetic acid, and ammonia nitrogen) fed back by the metabolic flow monitoring sensors, nutrient salts (such as phosphorus sources and trace element Fe) are dynamically adjusted. 3+ Mn 2+ The frequency and dosage of the dosing pump were adjusted to regulate the ratio of PN / A bacteria to Candida utilis at 3:1, ensuring optimal microbial growth and targeted enhancement of the metabolic pathway from ammonia nitrogen → N2 small organic molecules → single-cell protein (SCP), thereby efficiently degrading pollutants. Simultaneously, based on the activity status and reaction rate of microorganisms in each zone, the power and frequency of the ultrasonic waves in the microbial activity regulation module were adjusted in real time (frequency 20~40kHz, power 50~100W). Appropriate ultrasonic stimulation can promote cell membrane permeability, accelerate mass transfer, increase the ammonia nitrogen degradation rate by 35%, and the SCP synthesis rate by 40%. When the metabolic flow monitoring sensor detects a decrease in the reaction rate, the PLC intelligent control system automatically optimizes the ultrasonic parameters through the microbial activity regulation module to reactivate the reaction system. The final purified gas discharged from the aerobic zone (H2S ≤ 0.05 mg / m³) 3 NH3 ≤ 0.1 mg / m³ 3 Tar mist ≤ 0.01 mg / m³ 3 HCN ≤ 0.005 mg / m 3 The traceability code is simultaneously provided to downstream users when the material is introduced into the fermentation system.

[0105] After treatment by the PN / A-Candida utilis metabolic flow precision control unit, the effluent from the aerobic zone enters the desulfurization tower of the all-element graded resource recovery unit to remove moisture (moisture content ≤0.5%), and then enters the sulfide catalytic conversion device (temperature 300~350℃, pressure 0.3~0.5MPa, in this embodiment 300℃, pressure 0.4MPa). The sulfide is directionally catalytically converted into elemental sulfur using the Co-Mo / Al2O3 catalyst, and then passed through a supercritical fluid. The sulfur is purified using a CO2 purification and circulation device. In this device, sulfur undergoes depressurization desorption, activated carbon adsorption for impurity removal, condensation and liquefaction, and pressurization and heating to achieve a purity ≥99.95% and a circulation recovery rate ≥99%. After purification, the sulfur is then subjected to a series of processes using an SCP refining system: washing, spray drying (120~150℃, 130℃ in this example), sieving (100~200μm), and ultraviolet irradiation sterilization (dose 25~30mJ / cm²). 2 ), obtained SCP as feed ingredient, and the product meets the first-class standard of "Feed Ingredient Single-Cell Protein" (GB / T 38587-2020).

[0106] The resource recovery rate of the entire system of this invention is ≥45%, and the resource recovery value per unit of coal gas treated is ≥2.3 yuan / Nm³. 3 .

[0107] The PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation employs a random forest algorithm for parameter prediction and intelligent regulation. It automatically sends regulation commands when deviations from thresholds, with a response time ≤3s. Through real-time data acquisition, it intelligently regulates system parameters, and generates traceability codes by uploading carbon footprint data to the blockchain. During application, a multi-dimensional data acquisition module receives data from the online pollutant concentration monitoring and feedback module in the supercritical CO2 fluid circulation-heat exchange integrated system, the trace pollutant-specific sensing module in the supramolecular biomimetic MOFs intelligent adaptation sieving unit, the metabolic flow monitoring sensor in the PN / A-Candida utilis metabolic flow precision regulation unit, and the resource purity online detection module in the all-element graded resource recovery unit. This data is then transmitted to ANSYS. The data is processed using a Fluent+Python coupled digital twin model. After processing, the data is stored in a consortium blockchain traceability system. The consortium blockchain traceability system adopts a consortium blockchain + IPFS distributed storage architecture (on-chain data generates a unique traceability code, supporting multi-institution queries), with 5 nodes. Then, the data enters the intelligent decision control module to make a decision. The intelligent decision control module controls the signals of each adaptive control valve group, the intelligent adjustment device for the number of membrane stacking layers, the adsorption-regeneration linkage system, the nutrient salt precision dosing system, and the microbial activity regulation module. After making a decision, the intelligent decision control module realizes the adjustment and control of each unit.

[0108] Among them, the PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation uses ANSYS Fluent + Python to couple the digital twin model to intelligently regulate system parameters, and at the same time records carbon footprint data and generates a unique traceability code through the consortium blockchain traceability system.

[0109] The ANSYS Fluent+Python coupled digital twin model and consortium blockchain traceability system are detailed below:

[0110] Data Acquisition and Simulation (Perception Layer):

[0111] The system uses ANSYS Fluent software to perform fluid dynamics simulation of the entire purification process (from pyrolysis to photocatalysis to supercritical).

[0112] On-site sensors collect real-time data on gas flow, temperature, pressure, and pollutant concentration, and input the data into the Fluent model for real-time calibration, establishing a "digital twin" synchronized with the physical entity;

[0113] Intelligent decision-making (brain level):

[0114] The Python script serves as the core of the control logic, reading the simulation results and real-time sensor data from the digital twin model.

[0115] The Python algorithm dynamically adjusts the operating parameters of the three cascaded units based on the type and concentration of pollutants.

[0116] If a high tar content is detected, Python will automatically increase the peak voltage of the plasma generator (e.g., from 15kV to 25kV).

[0117] If residual ammonia is detected, Python will adjust the light intensity or gas residence time of the photocatalytic reaction bed.

[0118] If the system temperature is too high, Python will instruct the supercritical CO2 system to increase the circulation flow rate to enhance heat exchange and cooling.

[0119] Execution and Feedback (Execution Layer):

[0120] The control commands issued by Python are sent to various hardware devices (high-voltage power supply, valves, pumps) through the PLC (Programmable Logic Controller).

[0121] At the same time, the system puts all operational data (energy consumption, processing volume, removal rate) on the blockchain to achieve an immutable record of the carbon footprint for subsequent carbon trading accounting or environmental compliance audits.

[0122] Closed-loop control:

[0123] The trace pollutant sensor module (MS-100) at the outlet continuously monitors the purification effect. If the outlet concentration exceeds the standard, the system will immediately trigger an alarm and automatically backtrack to adjust the parameters of the preceding units, forming a fully closed-loop intelligent control process of monitoring, simulation, decision-making, execution, and re-monitoring.

[0124] In this embodiment, the flow rate of the original gas is 500 Nm³. 3 / h, its pollutant concentration H2S is 850mg / m³ 3 COS is 65 mg / m² 3 Tar mist is 120 mg / m³ 3 NH3 is 80 mg / m³ 3 HCN is 15 mg / m² 3 The effective components are CO 25%, CO2 15%, H2 55%, CH4 3%, and N2 2%. The gas is treated using the aforementioned ultra-deep purification method for coal gas fermentation based on pyrolysis-precision sieving-flow-directed control. Specifically, in the cross-media synergistic pyrolysis unit, the pulse width of the bipolar nanosecond pulsed plasma generator is 30-50 ns, the peak voltage is 25 kV, the temperature of the gradient-doped photocatalytic reaction bed is 35℃, and the supercritical CO2 flow rate of the supercritical CO2 fluid circulation-heat exchange integrated system is 2 m / s, and the pressure is 7.8 MPa. In the supramolecular biomimetic MOFs intelligent adaptive sieving unit, the initial membrane stack number is 8 layers, the flow rate of the extracted coal gas entering the membrane module is 0.8 m / s, and the adsorption-regeneration linkage system... The regeneration cycle is 12 hours (repeated with 12 minutes of thermal regeneration and 6 minutes of CO2 backflushing); in the PN / A-Candida utilis metabolic flow precision control unit, the HRT in the anaerobic zone is 10 hours, the HRT in the microaerobic zone is 5 hours, and the HRT in the aerobic zone is 5 hours. The ultrasonic frequency of each zone is 30 kHz, the power is 80 W, and the C / N ratio is 3:1. The dissolved oxygen concentration is 0.08 mg / L in the anaerobic zone, 0.3 mg / L in the microaerobic zone, and 1.2 mg / L in the aerobic zone; the catalytic conversion temperature of the sulfide catalytic conversion device in the all-element graded resource recovery unit is 320℃, the pressure is 0.4 MPa, and the spray drying temperature of the SCP purification system is 130℃.

[0125] The final purified gas concentration of H2S after treatment using the above method is 0.03 mg / m³. 3 NH3 is 0.08 mg / m³ 3 Tar mist was 0.008 mg / m³. 3 HCN was 0.003 mg / m³. 3 COS was not detected; meanwhile, the sulfur recovery rate was 4.2 kg / h (purity 99.92%) and the SCP recovery rate was 12.5 kg / h (protein content 61.2%); the energy consumption of the entire process was 0.72 kWh / Nm³.3 The resource recovery rate is 47.3%; when the original gas flow rate fluctuates by ±20%, the purification efficiency fluctuates by 1.5%.

[0126] Example 2: A method for ultra-deep purification of coal gas at the fermentation stage based on pyrolysis-precision screening-flow-directed control

[0127] In this embodiment, the flow rate of the original gas is 800 Nm³. 3 / h, its pollutant concentration H2S is 120mg / m³ 3 COS is 20 mg / m² 3 Tar mist is 30 mg / m³ 3 NH3 is 35 mg / m³ 3 HCN is 5 mg / m 3 The effective components contained were 28% CO, 18% CO2, 3% H2, 0.5% CH4, and 50.5% N2. The gas was treated using the coal gas fermentation-level ultra-deep purification method based on pyrolysis-precision sieving-flow-directed control described in Example 1, with the only differences being: the pulse width of the bipolar nanosecond pulsed plasma generator in the cross-media synergistic pyrolysis unit was 20-30 ns, the peak voltage was 20 kV, the photocatalytic reaction bed temperature was 32°C, the gas phase residence time was 3 s, the supercritical CO2 flow rate in the supercritical CO2 fluid circulation-heat exchange integrated system was 1.5 m / s, and the pressure was 7.5 MPa; in the supramolecular biomimetic MOFs intelligent adaptive sieving unit, the initial membrane stack number was 5 layers, and the flow rate of the extracted coal gas entering the membrane module was 1.2 m / s. The regeneration cycle of the adsorption-regeneration linkage system is 15 hours (repeated for 12 minutes of thermal regeneration and 6 minutes of CO2 backflushing); in the PN / A-Candida utilis metabolic flow precision control unit, the HRT in the anaerobic zone is 8 hours, the HRT in the microaerobic zone is 4 hours, and the HRT in the aerobic zone is 4 hours. The ultrasonic frequency of each zone is 25 kHz, the power is 60 W, the C / N ratio is 3:1, and the dissolved oxygen concentration is 0.08 mg / L in the anaerobic zone, 0.3 mg / L in the microaerobic zone, and 1.2 mg / L in the aerobic zone; the catalytic conversion temperature of the sulfide catalytic conversion device in the all-element graded resource recovery unit is 310℃, the pressure is 0.35 MPa, and the spray drying temperature of the SCP purification system is 125℃.

[0128] The final purified gas concentration of H2S after treatment using the above method is 0.04 mg / m³. 3 NH3 is 0.09 mg / m³ 3 Tar mist was 0.009 mg / m³. 3 HCN was 0.004 mg / m³. 3COS was not detected; meanwhile, the sulfur recovery rate was 0.95 kg / h (purity 99.91%), and the SCP recovery rate was 8.2 kg / h (protein content 60.5%); the energy consumption of the entire process was 0.76 kWh / Nm³. 3 The resource recovery rate is 44.1%; when the pollutant concentration fluctuates by ±30%, the purification efficiency fluctuates by 1.8%.

[0129] Example 3: A method for ultra-deep purification of coal gas at the fermentation stage based on pyrolysis-precision screening-flow-directed control

[0130] In this embodiment, the flow rate of the original gas is 300 Nm³. 3 / h, its pollutant concentration H2S is 350mg / m³ 3 COS is 40 mg / m² 3 Tar mist is 80 mg / m³ 3 NH3 is 50 mg / m³ 3 HCN is 10 mg / m 3 The effective components contained were 22% CO, 16% CO2, 58% H2, 2% CH4, and 2% N2. The gas was treated using the coal gas fermentation-level ultra-deep purification method based on pyrolysis-precision sieving-flow-directed control described in Example 1, with the only differences being: the pulse width of the bipolar nanosecond pulsed plasma generator in the cross-media synergistic pyrolysis unit was 10-20 ns, the peak voltage was 18 kV, the photocatalytic reaction bed temperature was 31.1℃, the gas phase residence time was 5 s, the supercritical CO2 flow rate in the supercritical CO2 fluid circulation-heat exchange integrated system was 1.8 m / s, and the pressure was 7.38 MPa; in the supramolecular biomimetic MOFs intelligent adaptive sieving unit, the initial membrane stack number was 6 layers, and the flow rate of the extracted coal gas entering the membrane module was 0.6 m / s. The regeneration cycle of the adsorption-regeneration linkage system is 10 hours (repeated with 12 minutes of thermal regeneration and 6 minutes of CO2 backflushing); in the PN / A-Candida utilis metabolic flow precision control unit, the HRT of the anaerobic zone is 12 hours, the HRT of the microaerobic zone is 6 hours, and the HRT of the aerobic zone is 6 hours. The ultrasonic frequency of each zone is 35 kHz, the power is 70 W, the C / N ratio is 3:1, and the dissolved oxygen concentration is 0.08 mg / L in the anaerobic zone, 0.3 mg / L in the microaerobic zone, and 1.2 mg / L in the aerobic zone; the catalytic conversion temperature of the sulfide catalytic conversion device in the all-element graded resource recovery unit is 330℃, the pressure is 0.45 MPa, and the spray drying temperature of the SCP purification system is 135℃.

[0131] The final purified gas concentration of H2S after treatment using the above method is 0.02 mg / m³. 3 NH3 is 0.07 mg / m³ 3 Tar mist concentration was 0.007 mg / m³.3 HCN was 0.002 mg / m³. 3 COS was not detected; meanwhile, the sulfur recovery rate was 1.7 kg / h (purity 99.93%) and the SCP recovery rate was 7.8 kg / h (protein content 62.0%); the energy consumption of the entire process was 0.70 kWh / Nm³. 3 The resource recovery rate is 46.8%; when the original gas flow rate fluctuates by ±20% and the pollutant concentration is -30%, the purification efficiency fluctuates by 1.2%.

[0132] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A method for ultra-deep purification of coal gas at the fermentation stage based on pyrolysis-precision sieving-flow-directed control, characterized in that, The method includes the following specific steps: Gradient composite photocatalytic materials are added into a bipolar nanosecond pulsed plasma generator and activated using high-energy electrons. The activated gradient composite photocatalytic material, together with the dust-removed and cooled coal gas to be treated, enters the gradient-doped photocatalytic reaction bed to carry out the cracking reaction to remove H2S, COS and tar mist; The pyrolysis products are fed into a supercritical CO2 fluid circulation-heat exchange integrated system for supercritical extraction to further remove H2S. After extraction, the gas enters the membrane module of the supramolecular biomimetic MOFs intelligent adaptive sieving unit at a speed of 0.5~2 m / s for precise sieving. During the sieving process, the residual concentrations of NH3 and HCN in the gas after sieving at the outlet of the membrane module are monitored by a trace pollutant-specific sensing module to achieve ppb-level precise sieving. Based on the residual concentration data, the intelligent adjustment device for the number of membrane stacking layers is used to adjust the number of composite biomimetic membrane stacking layers in the module and control the adsorption and regeneration speed of the adsorption-regeneration linkage system. After screening, the coal gas enters the partitioned co-culture reaction tank of the PN / A-Candida utilis metabolic flow precision control unit. The small molecule organic matter and ammonia nitrogen remaining in the coal gas are subjected to anaerobic, microaerobic and aerobic treatment in sequence to degrade pollutants and synthesize SCP. The final purified gas discharged after aerobic treatment is introduced into the fermentation system, and the traceability code is provided to downstream users simultaneously. After the PN / A-Candida utilis metabolic flow precise control unit is completed, the effluent from the aerobic zone enters the desulfurization tower of the all-element graded resource recovery unit to remove moisture, and then enters the sulfide catalytic conversion device to be directionally catalytically converted into elemental sulfur. It is then purified by the supercritical CO2 purification and circulation device. In the supercritical CO2 purification and circulation device, it undergoes depressurization desorption, activated carbon adsorption to remove impurities, condensation liquefaction and pressurization and heating. The purified elemental sulfur is then used by the SCP refining system to be washed, spray dried, screened and sterilized by ultraviolet irradiation in sequence to obtain SCP as feed raw material. The PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation uses random forest algorithm for parameter prediction and intelligent regulation. During application, the multi-dimensional data acquisition module receives data from the pollutant concentration online monitoring and feedback module in the supercritical CO2 fluid circulation-heat exchange integrated system, the trace pollutant specific sensing module in the supramolecular biomimetic MOFs intelligent adaptive sieving unit, the metabolic flow monitoring sensor in the PN / A-Candida utilis metabolic flow precision control unit, and the resource purity online detection module in the all-element graded resource recovery unit. This data is then transmitted to the ANSYS Fluent+Python coupled digital twin model for processing. After processing, the data is stored in the consortium blockchain traceability system and then enters the intelligent decision control module to make decisions. The intelligent decision control module controls various adaptive control valve groups, the intelligent membrane stacking layer number adjustment device, the adsorption-regeneration linkage system, the nutrient salt precision dosing system, and the microbial activity regulation module via signal connections. After making a decision, the intelligent decision control module adjusts and controls each unit.

2. The method according to claim 1, characterized in that, The gradient composite photocatalytic material is a Ti substrate with a bottom layer thickness of 5 mm. 0.8 Fe 0.2 O2, Ti with a middle layer thickness of 3mm 0.7 Cu 0.3 O2 and Ti with a top layer thickness of 2mm 0.6 Zn 0.4 O2.

3. The method according to claim 1, characterized in that, The pulse width of the bipolar nanosecond pulsed plasma generator is 5~50ns and the peak voltage is 10~30kV.

4. The method according to claim 1, characterized in that, The temperature of the gradient-doped photocatalytic reaction bed is 31.1~40℃, and the gas phase residence time is 2.5~8s; The supercritical CO2 fluid in the supercritical CO2 fluid circulation-heat exchange integrated system is controlled at a critical temperature of 31.1~40℃ and a pressure of 7.38~8.0MPa. The flow rate of the extracted coal gas entering the supramolecular biomimetic MOFs intelligent adaptive sieving unit is 0.5~2m / s.

5. The method according to claim 1, characterized in that, During the screening process, when the concentrations of NH3 and HCN are found to be excessive, the PLC intelligent control system controls the intelligent adjustment device for the number of membrane stacking layers to automatically increase the number of composite biomimetic membrane stacking layers in the module, while reducing the gas flow rate of the extracted gas entering the membrane module to prolong the reaction residence time. When the concentration is detected to be far below the threshold, the intelligent adjustment device for controlling the number of membrane stacking layers automatically reduces the number of composite biomimetic membrane stacking layers in the module, while appropriately increasing the gas flow rate of the extracted gas entering the membrane module. When the residual concentrations of NH3 and HCN in the screened gas exceed the set safety thresholds, the PLC intelligent control system determines that the currently operating membrane stack module is close to adsorption saturation and needs to enter the regeneration process. The intelligent adjustment device for the number of membrane stack layers will physically remove the composite bionic membrane determined to be saturated from the main airflow or switch it through a valve to remove it from the main purification channel and enter the closed regeneration chamber of the adsorption-regeneration linkage system. At the same time, the PLC intelligent control system issues a command to start the adsorption-regeneration linkage system, switch the gas path valves and start the heating device to purge and desorb pollutants with hot air, and then heat the inert carrier gas to a specific temperature. The resulting hot airflow passes in reverse through the composite bionic membrane. After the hot purge, or for pollutants with poor thermal stability, the adsorption-regeneration linkage system injects CO2 into the regeneration chamber and pressurizes and heats it to a supercritical state for supercritical cleaning. After the regeneration process is completed, a cold, dry, inert gas is introduced to rapidly cool the composite biomimetic membrane to room temperature, preventing high temperatures from damaging organic components such as chitosan. At the same time, the PLC intelligent control system may perform a brief self-check to confirm that the membrane has regained its activity. The intelligent adjustment device for the number of membrane stacking layers will reinsert the regenerated composite biomimetic membrane into the working position, or switch it back to the main gas flow through a valve to enter the next adsorption cycle.

6. The method according to claim 1, characterized in that, The carbon-nitrogen ratio of each zone in the partitioned co-culture reactor is 3:

1. The dissolved oxygen concentration in the anaerobic zone is ≤0.1mg / L, the dissolved oxygen concentration in the microaerobic zone is 0.2~0.5mg / L, and the dissolved oxygen concentration in the aerobic zone is 1.0~1.5mg / L. The temperature in each zone is 28~32℃ and the pH value is 7.2~7.

8. During the treatment process, metabolic flow monitoring sensors monitor the metabolic activity, substrate consumption rate, and product (SCP) generation rate of microorganisms in the reaction tank in real time. Based on the C / N / P nutrient ratio required for microbial growth and the substrate consumption feedback from the metabolic flow monitoring sensors, the frequency and dosage of nutrient salt dosing pumps are dynamically adjusted to maintain the ratio of PN / A bacteria to Candida utilis at 3:1, ensuring that the microorganisms are in optimal growth condition. Simultaneously, based on the activity status and reaction rate of microorganisms in each zone, the power and frequency of ultrasound in the microbial activity regulation module are adjusted in real time. When the metabolic flow monitoring sensors detect a decrease in reaction rate, the PLC intelligent control system automatically optimizes the ultrasound parameters by controlling the microbial activity regulation module.

7. The method according to claim 1, characterized in that, The catalytic conversion unit for sulfide catalytic conversion operates at a temperature of 300~350℃, a pressure of 0.3~0.5MPa, and uses Co-Mo / Al2O3 as the catalyst. The spray drying temperature in the SCP refining system is 120~150℃, the particle size of the sieve is 100~200μm, and the UV sterilization dose is 25~30mJ / cm. 2 .

8. The method according to claim 1, characterized in that, The PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation uses ANSYS Fluent+Python to couple digital twin models to intelligently regulate system parameters, while recording carbon footprint data and generating unique traceability codes through a consortium blockchain traceability system. The ANSYS Fluent+Python coupled digital twin model and consortium blockchain traceability system are detailed below: Data Acquisition and Simulation: The system uses ANSYS Fluent software to perform fluid dynamics simulation of the entire purification process; On-site sensors collect real-time data on gas flow, temperature, pressure, and pollutant concentration, and input the data into the Fluent model for real-time calibration, establishing a "digital twin" synchronized with the physical entity; Intelligent decision-making: The Python script serves as the core of the control logic, reading the simulation results and real-time sensor data from the digital twin model. The Python algorithm dynamically adjusts the operating parameters of the three cascaded units based on the type and concentration of pollutants. When a high tar content is detected, Python will automatically increase the peak voltage of the plasma generator; When residual ammonia is detected, Python will adjust the light intensity or gas residence time of the photocatalytic reaction bed. When the system temperature is too high, Python will instruct the supercritical CO2 system to increase the circulation flow rate to enhance heat exchange and cooling. Implementation and Feedback: Control commands issued by Python are sent to various hardware devices via the PLC; At the same time, the system uploads all operational data to the blockchain to achieve an immutable record of the carbon footprint, which can be used for subsequent carbon trading accounting or environmental compliance audits. Closed-loop control: The trace pollutant sensing module at the outlet continuously monitors the purification effect; when the outlet concentration exceeds the standard, the system will immediately trigger an alarm and automatically backtrack to adjust the parameters of the preceding units, forming a fully closed-loop intelligent control process of monitoring, simulation, decision-making, execution, and re-monitoring.

9. A coal gas fermentation-level ultra-deep purification system based on pyrolysis-precision screening-flow-directed control, characterized in that, The system is used in the method according to any one of claims 1-8; The system includes a cross-media collaborative pyrolysis unit, a supramolecular biomimetic MOFs intelligent adaptation sieving unit, a PN / A-candida utilis metabolic flow precise regulation unit, and a full-element graded resource recovery unit, which are connected in series through adaptive control valve groups. It also includes a PLC intelligent control system that communicates bidirectionally with each unit, which is a digital twin-blockchain carbon footprint traceability and intelligent regulation system. The PLC intelligent control system is signal-connected to each adaptive control valve group. The cross-media synergistic pyrolysis unit includes a bipolar nanosecond pulsed plasma generator, a gradient-doped photocatalytic reaction bed, and a supercritical CO2 fluid circulation-heat exchange integrated system connected in series. The outlet of the supercritical CO2 fluid circulation-heat exchange integrated system is also connected to the inlet of the supramolecular biomimetic MOFs intelligent adaptive sieving unit through an adaptive control valve group. The supramolecular biomimetic MOFs intelligent adaptive sieving unit includes a membrane module, an intelligent adjustment device for the number of membrane stacks, an adsorption-regeneration linkage system, and a trace pollutant-specific sensing module. The membrane module is composed of at least one Zn-MOF-74@cellulose-chitosan composite biomimetic membrane stacked in parallel, and the membrane module is vertically arranged in the central core area of ​​the sieving unit. The intelligent adjustment device for the number of membrane stacks is directly connected to the membrane module, and the adjustment device is assembled on the top of the membrane module. Its output end is fixedly connected to the top of the membrane module and is powered by a drive motor. The adsorption-regeneration linkage system forms a closed loop connection with the membrane module. It is arranged around the outside of the membrane module and is connected to the inlet and outlet of the membrane module. The trace pollutant-specific sensing module is fixedly installed on the outlet side of the membrane module, with its detection probe facing the discharge end of the membrane module. The trace pollutant-specific sensing module is connected to the PLC intelligent control system. The PLC intelligent control system is also connected to the intelligent adjustment device for the number of membrane stacks and the adsorption-regeneration linkage system. The PN / A-Candida utilis metabolic flow precision control unit includes a partitioned co-culture reaction tank. The tank is divided into three independent and interconnected reaction zones: an anaerobic zone, a microaerobic zone, and an aerobic zone, which are arranged in sequence by partitions. The partitions have reserved connection ports. The inlet end of the anaerobic zone is also connected to the outlet end of the membrane module. The PN / A-Candida utilis metabolic flow precision control unit also includes a nutrient salt precision dosing system. Its discharge end is connected to the anaerobic zone, microaerobic zone and aerobic zone inside the reaction tank through a conveying pipeline, and the outlet end of the conveying pipeline extends into each zone. The anaerobic, microaerobic, and aerobic zones are equipped with metabolic flow monitoring sensors and microbial activity regulation modules. The metabolic flow monitoring sensors are installed on the inner side of the pool wall of each zone, and the detection probes extend to the material reaction area of ​​each zone. The signal output terminals of the metabolic flow monitoring sensors are connected to the metering pump of the nutrient salt precision dosing system and the microbial activity regulation module through the PLC intelligent control system. The microbial community activity regulation module is installed on the outside of each zone, and the ultrasonic transmitter is fixedly connected to the wall of each zone. The control end of the microbial community activity regulation module establishes a signal connection with the metabolic flow monitoring sensor through the PLC intelligent control system. The all-element graded resource recovery unit includes a desulfurization tower, a sulfide catalytic conversion device, a supercritical CO2 purification and circulation device, an SCP refining system, and an online resource purity detection module; The desulfurization tower is located at the front of the unit. Its inlet is connected to the outlet of the aerobic tank, and its outlet is connected to the inlet of the sulfide catalytic conversion device. The outlet of the sulfide catalytic conversion device is connected to the inlet of the supercritical CO2 purification and circulation device. The SCP purification system is arranged in parallel behind the supercritical CO2 purification and circulation device and is connected to the outlet of the supercritical CO2 purification and circulation device. The online resource purity detection module is connected to the discharge end of the sulfide catalytic conversion unit, the supercritical CO2 purification and circulation unit, and the SCP refining system, respectively, and the detection probe corresponds to the discharge end of each unit. The PLC intelligent control system for digital twin-blockchain carbon footprint traceability and intelligent regulation includes a multi-dimensional data acquisition module connected by sequential signals, an ANSYS Fluent+Python coupled digital twin model, a consortium blockchain traceability system, and an intelligent decision control module. Among them, the multi-dimensional data acquisition module is connected to the pollutant concentration online monitoring and feedback module in the supercritical CO2 fluid circulation-heat exchange integrated system, the trace pollutant specific sensing module in the supramolecular biomimetic MOFs intelligent adaptation sieving unit, the metabolic flow monitoring sensor in the PN / A-Candida utilis metabolic flow precise regulation unit, and the resource purity online detection module in the all-element graded resource recovery unit. The intelligent decision control module is connected to each adaptive control valve group, the intelligent adjustment device for the number of membrane stacks, the adsorption-regeneration linkage system, the nutrient salt precision dosing system, and the microbial activity regulation module.

10. The system according to claim 9, characterized in that, In the cross-medium synergistic pyrolysis unit, an adaptive control valve group is installed between the three devices: the bipolar nanosecond pulsed plasma generator, the gradient-doped photocatalytic reaction bed, and the supercritical CO2 fluid circulation-heat exchange integrated system. The adaptive control valve group is connected to the PLC intelligent control system. At the same time, the supercritical CO2 fluid circulation-heat exchange integrated system is also equipped with a pollutant concentration online monitoring and feedback module, which is also connected to the PLC intelligent control system. The PLC intelligent control system is also connected to the supercritical CO2 fluid circulation-heat exchange integrated system.

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