A multi-stage pressure swing feeding device based on a pressurized fluidized bed gasifier

Abstract

The application provides a multi-stage variable-pressure feeding device based on a pressurized fluidized bed gasification furnace, which comprises a multi-stage gradient pressure cabin, the multi-stage gradient pressure cabin comprises a normal-pressure pretreatment cabin, a medium-pressure transition cabin and a high-pressure transition cabin arranged in sequence from top to bottom, and pressure gradient is realized through a sealing isolation mechanism between cabin sections; the normal-pressure pretreatment cabin is internally provided with a biomimetic myxomycete fiber net and a microwave plasma pretreatment module; the medium-pressure transition cabin and the high-pressure transition cabin are both provided with a magnetic suspension execution unit; and the application further comprises a control system electrically connected with the microwave plasma pretreatment module, the magnetic suspension execution unit and sensors arranged in the cabin sections. The application realizes multi-stage pressure transition by decomposing high-pressure sealing into multi-stage pressure transition through the step-by-step variable-pressure design of the three-stage gradient pressure cabin, reduces single-stage pressure difference and sealing energy consumption, realizes non-blocking dispersion and rapid dehydration of large-size and high-moisture materials through the biomimetic myxomycete fiber net and the microwave plasma pretreatment module, avoids material adhesion and accumulation bridging through the magnetic suspension execution unit, and realizes full-process automatic collaborative control through the control system.

Description

Technical Field

[0001] This invention relates to the field of energy and chemical technology, and in particular to a multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier. Background Technology

[0002] The resource utilization of agricultural waste has become a core issue in energy structure transformation, ecological environmental protection, and sustainable agricultural development. Traditional disposal methods result in energy waste and ecological burden, while traditional gasification technology faces three major world-class challenges in treating agricultural waste: difficulty in feeding materials, low efficiency, and high tar content, which seriously restricts the industrial-scale gasification utilization.

[0003] Pressurized fluidized bed gasification technology, due to its high conversion efficiency and low pollutant emissions, has been listed as a key technology for the large-scale utilization of biomass energy in my country. However, the technical bottlenecks that its feeding system has long faced have severely restricted its industrial implementation.

[0004] 1. Conflict between energy consumption and "dual carbon" goals: Traditional feeding devices rely on mechanical seals or packing seals to maintain a high-pressure environment of 1~10MPa in the gasifier, and the energy consumption of the seals accounts for 30%~40% of the total energy consumption of the system, which is contrary to my country's energy development needs of "reducing carbon emissions and reducing energy consumption".

[0005] 2. Material compatibility does not meet the realities of rural areas: Agricultural waste in my country is characterized by its dispersed sources, uneven size (maximum diameter exceeding 20cm), and large fluctuations in moisture content (30%~70%). Traditional equipment requires complex pretreatment processes (crushing and drying), increasing equipment investment and operation and maintenance costs, making it difficult to adapt to large-scale application scenarios in rural areas.

[0006] 3. Stability restricts industrial scaling: The response lag of multi-stage pressure switching is ≥100ms. Pressure fluctuations cause the gasifier reaction conditions to become unbalanced, and the gasification efficiency decreases by 10%~15%, which cannot meet the requirements of "large-scale and high stability" industrial development of biomass energy in my country.

[0007] 4. In the face of national policies such as "banning the burning of agricultural waste" and "comprehensive utilization of straw", existing equipment is difficult to achieve the dual goals of "environmental compliance + resource value-added" due to low conversion efficiency and high operating costs, resulting in a large amount of agricultural waste remaining idle. Summary of the Invention

[0008] To address the aforementioned technical problems, this invention proposes a multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier, which solves the problems of existing fluidized bed gasifier feeding devices that mostly use single-stage or two-stage pressure, rely on mechanical packing seals, and suffer from rapid wear and high energy consumption.

[0009] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0010] A multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier includes a multi-stage gradient pressure chamber, comprising an atmospheric pressure pretreatment chamber, a medium-pressure transition chamber, and a high-pressure transition chamber arranged sequentially from top to bottom. Pressure gradients are achieved between the chambers through a sealing and isolation mechanism. The atmospheric pressure pretreatment chamber is equipped with a biomimetic slime mold fiber mesh and a microwave plasma pretreatment module. Both the medium-pressure and high-pressure transition chambers are equipped with magnetic levitation actuators. The device also includes a control system, which is electrically connected to the microwave plasma pretreatment module, the magnetic levitation actuators, and sensors located in each chamber. This invention, through the step-by-step pressure variation design of the three-stage gradient pressure chambers, decomposes the high-pressure seal into multi-stage pressure transitions, reducing single-stage pressure difference and sealing energy consumption. The biomimetic slime mold fiber mesh and microwave plasma pretreatment module enable non-clogging dispersion and rapid dehydration of large-sized, high-moisture materials. The magnetic levitation actuators allow materials to flow in a non-contact suspended state, completely avoiding material adhesion and bridging. The control system is electrically connected to each module, achieving fully automated and coordinated control of the entire process.

[0011] Furthermore, in order to achieve the functions of material dispersion and pretreatment, the biomimetic slime mold fiber mesh is laid laterally inside the atmospheric pressure pretreatment chamber; the microwave plasma pretreatment module is embedded in the side wall of the atmospheric pressure pretreatment chamber.

[0012] Furthermore, to facilitate the acquisition of the particle size and moisture content of the material, a feed inlet is provided at the top of the atmospheric pressure pretreatment chamber; a quantum dot material sensor is installed at the feed inlet to detect the particle size and moisture content of the material.

[0013] Furthermore, in order to achieve pressure isolation between the three-stage compartments, the sealing isolation mechanism includes a first rotary sealing gate valve and a second rotary sealing gate valve; the first rotary sealing gate valve is located between the atmospheric pressure pretreatment compartment and the intermediate pressure transition compartment; the second rotary sealing gate valve is located between the intermediate pressure transition compartment and the high pressure transition compartment; the first rotary sealing gate valve and the second rotary sealing gate valve are opened and closed alternately.

[0014] Furthermore, in order to remove dirt from the sealing surface in real time, the first rotary sealing gate valve includes a valve body, a rotating main shaft with a valve plate disposed in the valve body, a central cone seat and an annular mounting seat coaxially connected to the rotating main shaft; an ultrasonic cavitation cleaning ring is integrated inside or on the surface of the central cone seat; a shape memory alloy spring brush is provided on the annular mounting seat, and the shape memory alloy spring brush is arranged around the ultrasonic cavitation cleaning ring; the rotating main shaft is driven by an external motor disposed outside the valve body.

[0015] Furthermore, in order to detect media leakage or residue inside the first rotary sealing gate valve, a fluorescent material sensor is also provided on the valve body. The fluorescent material sensor is located near the monitoring window of the valve body to detect media leakage or residue in the internal dynamic sealing gap, and triggers the ultrasonic cavitation cleaning ring and the shape memory alloy spring brush to perform cleaning.

[0016] Furthermore, to prevent fine debris from accumulating and clogging inside the chamber, the intermediate-pressure transition chamber includes an intermediate-pressure transition chamber body, an electromagnetic coil 1 located at the top of the intermediate-pressure transition chamber body, and a magnetically levitated pressure-resistant conical hopper 1 inside the intermediate-pressure transition chamber body; the magnetically levitated pressure-resistant conical hopper 1 generates a levitational magnetic field through the electromagnetic coil 1 to maintain a levitational gap 1 that is not in contact with the inner wall of the intermediate-pressure transition chamber body.

[0017] Furthermore, in order to enable the material to maintain non-contact suspension flow under a high pressure environment of 1~10MPa, the high pressure transition chamber includes a high pressure transition chamber body and an electromagnetic coil II located at the top of the high pressure transition chamber body. The high pressure transition chamber is equipped with a magnetically levitated pressure-resistant conical bucket II. The magnetically levitated pressure-resistant conical bucket II maintains a non-contact suspension gap II with the inner wall of the high pressure transition chamber by generating a suspension magnetic field through the electromagnetic coil II.

[0018] Furthermore, to assist in feeding, a screw feeder is provided at the bottom of the high-pressure transition chamber. One end of the screw feeder is connected to a motor, and a material blowing fan is coaxially connected to the rotating shaft of the screw feeder.

[0019] Furthermore, in order to form a smooth pressure gradient, the pressure gradient of the multi-stage gradient pressure chamber is as follows: the atmospheric pressure pretreatment chamber is at atmospheric pressure, the medium pressure transition chamber is 0.5~2MPa, and the high pressure transition chamber is 1~10MPa.

[0020] The beneficial effects of this invention are:

[0021] 1. This invention utilizes a three-stage gradient pressure chamber design: atmospheric pressure pretreatment chamber → medium-pressure transition chamber → high-pressure transition chamber. This design breaks down high-pressure sealing into multi-stage pressure transitions, and combined with magnetic levitation contactless sealing technology, significantly reduces the energy consumption of high-pressure sealing. Testing shows that the energy consumption of high-pressure sealing is ≤0.5kWh / t, a reduction of over 65% compared to traditional methods, meeting the carbon reduction and energy conservation requirements of the "dual carbon" target.

[0022] 2. This invention involves horizontally laying a biomimetic slime mold fiber mesh in an atmospheric pressure pretreatment chamber. The mesh structure, woven from modified carbon fiber with a porosity of 60% to 80%, can automatically wrap and disperse blocky materials with a size ≤30cm, preventing accumulation and bridging. Simultaneously, in conjunction with a microwave plasma pretreatment module, agricultural waste with a moisture content ≤70% can be rapidly dehydrated to below 20% within 10 to 20 seconds, eliminating the need for external crushing and drying equipment. This significantly broadens the adaptability of raw materials and reduces pretreatment costs.

[0023] 3. The present invention sets up a magnetic levitation execution unit in the medium-pressure transition chamber and the high-pressure transition chamber. The magnetic levitation pressure-resistant conical bucket maintains a non-contact suspension gap of 0.05~0.1mm with the inner wall of the chamber through electromagnetic coils, so that the material is suspended and dispersed, which completely avoids the adhesion, accumulation and bridging of fine residues. The blockage rate is as low as 0.03%, which is far superior to traditional devices.

[0024] 4. This invention uses a nickel-titanium shape memory alloy screw feeder, whose screw pitch can be automatically adjusted according to temperature or pressure (5~20cm). Combined with a quantum dot material sensor for real-time detection of material particle size (accuracy ±0.1mm), the control system can dynamically adjust the screw pitch and rotation speed to achieve adaptive and stable conveying of materials of different particle sizes (<10cm, 10~20cm, >20cm), with a feeding efficiency of 5.2t / h, an improvement of 200%.

[0025] 5. This invention integrates an ultrasonic cavitation cleaning ring and a shape memory alloy spring brush within the first rotary sealing gate valve, forming a composite self-cleaning mechanism of "mechanical brushing + ultrasonic cavitation"; at the same time, a fluorescent material sensor is set up to monitor the leakage or residue in the dynamic sealing gap in real time, and once the standard is exceeded, the cleaning is triggered, which effectively ensures the sealing reliability and stability of long-term operation.

[0026] 6. This invention employs quantum dot material sensors and fluorescent material sensors, combined with a PLC + touch screen control system, to achieve real-time online monitoring of material particle size, moisture content, and sealing leakage, as well as automated linkage of pressure regulation, feed speed control, and self-cleaning triggering. It supports manual / automatic switching and fault alarms, significantly improving the intelligence level and ease of operation and maintenance of the device.

[0027] 7. This invention is specifically designed for the characteristics of agricultural waste in my country, which is "large in size (≤30cm) and high in moisture (≤70%)". It can directly process raw materials such as straw and rice husks that have not undergone complex pretreatment. The feeding efficiency is ≥5t / h, the high-pressure sealing energy consumption is ≤0.5kWh / t, and the blockage rate is ≤0.1%. While meeting the environmental protection policy of prohibiting burning, it realizes the efficient recycling and energy utilization of agricultural waste resources, and has significant economic and ecological benefits. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of the present invention.

[0030] Figure 2 This is a schematic diagram of the atmospheric pressure pretreatment chamber of the present invention.

[0031] Figure 3 This is a schematic diagram of the sealing and isolation mechanism of the present invention.

[0032] Figure 4 This is a schematic diagram of the intermediate-pressure transition chamber of the present invention.

[0033] Figure 5 This is a schematic diagram of the high-pressure transition chamber of the present invention.

[0034] Figure 6 This is a schematic diagram of the process of the present invention.

[0035] In the diagram: 4. Atmospheric pressure pretreatment chamber; 401. Bionic slime mold fiber mesh; 402. Feed inlet; 403. Microwave plasma pretreatment module; 5. Sealing and isolation mechanism; 501. Ultrasonic cavitation cleaning ring; 502. Shape memory alloy spring brush; 503. Valve body; 504. Fluorescent material sensor; 6. Medium-pressure transition chamber; 601. Electromagnetic coil one. 603. Edge ring one; 604. Medium-pressure transition chamber; 605. Rotary outlet; 606. Second rotary sealing gate valve; 607. Suspension gap one; 608. Magnetic levitation pressure-resistant conical bucket one; 609. Medium-pressure transition chamber; 6010. Titanium alloy inner cavity; 7. High-pressure transition chamber; 701. Electromagnetic coil two; 702. Edge ring two; 703. Magnetic levitation pressure-resistant conical bucket two; 704. Outlet; 705. Motor; 707. High-pressure transition chamber; 708. Suspension gap two; 7010. Screw feeder; 7011. Material blowing fan. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier described in Embodiment 1 of the present invention, such as... Figures 1-6 As shown, the device comprises three pressure gradient chambers: an atmospheric pressure pretreatment chamber 4, a medium-pressure transition chamber 6, and a high-pressure transition chamber 7, from top to bottom. Pressure gradients are achieved between the chambers via a sealing and isolation mechanism 5. The atmospheric pressure pretreatment chamber 4 is at atmospheric pressure, the medium-pressure transition chamber 6 is at 0.5–2 MPa, and the high-pressure transition chamber 7 is at 1–10 MPa. This gradient design decomposes the high-pressure seal into multiple transition stages, reducing the pressure difference between individual stages and thus minimizing sealing energy consumption and leakage risk.

[0038] like Figure 2 As shown, the atmospheric pressure pretreatment chamber 4 is equipped with a biomimetic slime mold fiber mesh 401 and a microwave plasma pretreatment module 403. The biomimetic slime mold fiber mesh 401 is laid horizontally inside the atmospheric pressure pretreatment chamber 4, and is woven from modified carbon fibers into a mesh structure with a porosity of 60%~80%, mimicking the mesh morphology of slime mold hyphae. It can automatically wrap around and disperse blocky materials, preventing material accumulation and bridging, and ensuring that the material is evenly distributed in the central area of ​​the chamber. The microwave plasma pretreatment module 403 is embedded in the side wall of the atmospheric pressure pretreatment chamber 4. It bombards the material surface with low-temperature plasma, rapidly dehydrating high-moisture materials within 10~20 seconds, while simultaneously breaking down surface gelatinous impurities, creating favorable conditions for subsequent pressure transition and high-pressure conveying.

[0039] Furthermore, both the medium-pressure transition chamber 6 and the high-pressure transition chamber 7 are equipped with magnetic levitation actuators. Each magnetic levitation actuator includes an electromagnetic coil and a magnetically levitation pressure-resistant conical hopper. After being energized, the electromagnetic coil generates a levitation magnetic field, causing the conical hopper to levitate in the center of the chamber, maintaining a non-contact gap with the inner wall of the chamber. When materials fall, they are dispersed to the surrounding areas upon encountering the suspended conical hopper, preventing fine debris from accumulating and clogging at the bottom of the chamber. This non-contact flow guiding method completely solves the industry problem of material adhesion and bridging in traditional devices.

[0040] Furthermore, the atmospheric pressure pretreatment chamber 4 is equipped with a quantum dot material sensor (for detecting material particle size and moisture content) and a liquid level sensor; the medium-pressure transition chamber 6 and the high-pressure transition chamber 7 are both equipped with pressure sensors. The device also includes a control system, which uses a PLC and a touch screen, electrically connected to the microwave plasma pretreatment module 403, the electromagnetic coil of the magnetic levitation actuator, and the pressure sensors, liquid level sensors, and material sensors located in each chamber. The control system integrates functions such as material monitoring, pressure regulation, and feed rate control, and can adjust the operating parameters of each module in real time based on sensor feedback to achieve fully automatic closed-loop control.

[0041] In another embodiment, the control system is also connected to a pressure compensation unit, which may be a high-pressure air source buffer tank or a proportional regulating valve conventional in the art, to maintain the pressure stability of each compartment.

[0042] Example 2 further describes the specific structure of the sealing and isolation mechanism 5, such as... Figure 3As shown. The sealing and isolation mechanism includes a first rotary sealing gate valve 5 and a second rotary sealing gate valve 606. The first rotary sealing gate valve 5 is located between the atmospheric pressure pretreatment chamber 4 and the medium-pressure transition chamber 6; the second rotary sealing gate valve 606 is located between the medium-pressure transition chamber 6 and the high-pressure transition chamber 7. The first rotary sealing gate valve and the second rotary sealing gate valve 606 open and close alternately, with an opening and closing response time ≤50ms. This alternating action ensures that the pressure in each chamber does not leak during material transfer, maintaining a stable pressure gradient.

[0043] The first rotary sealing gate valve 5 includes a valve body, a rotating main shaft with a valve plate disposed within the valve body, a central cone seat coaxially connected to the rotating main shaft, and an annular mounting seat. For example... Figure 3 As shown, an ultrasonic cavitation cleaning ring 501 is integrated inside or on the surface of the central cone seat. A shape memory alloy spring brush 502 is mounted on the annular mounting base, and the shape memory alloy spring brush 502 is arranged in a ring around the ultrasonic cavitation cleaning ring 501. The rotating spindle is driven by an external motor located outside the valve body, causing the central cone seat, annular mounting base, and spring brushes to rotate synchronously. During operation, the spring brush rotates synchronously with the annular mounting base, utilizing the temperature response characteristics of the shape memory alloy to automatically adjust the fit between the brush bristles and the fixed sealing surface under different operating conditions, achieving self-compensating sealing, compensating for wear caused by long-term operation, and physically removing scale and particulate impurities from the sealing surface. Simultaneously, the ultrasonic cavitation cleaning ring 501 located at the center generates a high-frequency cavitation effect, forming micro-jets and shock waves within the sealing gap, peeling away stubborn stains. The synergistic effect of both forms a composite cleaning mechanism of "mechanical brushing + ultrasonic cavitation," which can effectively prevent media leakage and extend the seal life.

[0044] In addition, such as Figure 3 As shown, the valve body is also equipped with a fluorescent material sensor 504. The fluorescent material sensor 504 is located near the monitoring window of the valve body and is used to detect media leakage or residue in the dynamic sealing gap inside the first rotary gate valve 5. Once leakage or excessive dirt is detected, the sensor immediately sends a signal to the control system, triggering the ultrasonic cavitation cleaning ring 501 and the shape memory alloy spring brush 502 to perform cleaning. This achieves on-demand cleaning rather than timed cleaning, ensuring sealing reliability and avoiding unnecessary energy consumption.

[0045] The rest is the same as in Example 1.

[0046] Example 3: This example describes in detail the magnetic levitation actuator in the intermediate-pressure transition chamber 6, such as... Figure 4 As shown.

[0047] The intermediate-pressure transition chamber 6 includes an intermediate-pressure transition chamber body 604, an electromagnetic coil 601 located at the top of the intermediate-pressure transition chamber body 604, and a magnetically levitated pressure-resistant conical hopper 608 inside the intermediate-pressure transition chamber body 604. When the electromagnetic coil 601 is energized, it generates a controlled levitation magnetic field. Under the action of the magnetic field, the magnetically levitated pressure-resistant conical hopper 608 is suspended in the center of the chamber, maintaining a non-contact suspension gap 607 of 0.05~0.1mm between it and the inner wall of the intermediate-pressure transition chamber body 604. This gap is extremely small, sufficient to prevent a large amount of material particles from leaking from the sides, while ensuring smooth material passage. After entering the chamber from above, the material impacts the surface of the suspended conical hopper, is dispersed to the surrounding areas, and flows downwards along the annular gap between the conical surface and the chamber wall. Because the conical hopper is in a suspended state, material will not accumulate on its surface, and fine particles will not linger in the dead corners at the bottom of the chamber, thus completely avoiding the material bridging and clogging problems common in traditional equipment.

[0048] Furthermore, a pressure sensor is installed on the intermediate-pressure transition chamber 604 to monitor the internal pressure in real time and feed it back to the control system. When the pressure fluctuation exceeds the set value (e.g., 0.1 MPa), the control system immediately activates the pressure compensation unit to precisely replenish the pressure, ensuring that the pressure in the intermediate-pressure transition chamber 6 remains stable within the range of 0.5~2 MPa.

[0049] The rest is the same as in Example 2.

[0050] Example 4 describes in detail the magnetic levitation actuator in the high-pressure transition chamber 7. For example... Figure 5 As shown, the high-pressure transition chamber 7 includes a high-pressure transition chamber body 707 and an electromagnetic coil 701 located on top of the high-pressure transition chamber body 707. The high-pressure transition chamber 7 contains a magnetically levitated pressure-resistant conical bucket 703. The magnetically levitated pressure-resistant conical bucket 703 generates a levitation magnetic field through the electromagnetic coil 701, maintaining a non-contact levitation gap 708 with the inner wall of the high-pressure transition chamber body 707. Because the high-pressure transition chamber 7 operates at a higher pressure (1~10MPa), its chamber wall thickness and sealing requirements are correspondingly increased, but the working principle of levitation and flow guidance is the same as that of the medium-pressure transition chamber. This modular magnetic levitation design allows the same control logic to be applied to chambers of different pressure levels, reducing system complexity and manufacturing costs.

[0051] The rest is the same as in Example 3.

[0052] In Example 5, a screw feeder 7010 is provided at the bottom of the high-pressure transition chamber 707. One end of the screw feeder 7010 is connected to a motor 705, and the motor speed can be steplessly adjusted within the range of 0~50 r / min. A material blowing fan 7011 is coaxially connected to the rotating shaft of the screw feeder 7010. When the screw feeder rotates, the fan rotates accordingly, generating auxiliary airflow to blow the material towards the outlet 704, preventing the material from accumulating at the outlet.

[0053] Furthermore, the screw of the 7010 screw feeder is made of Ni-Ti shape memory alloy, and its pitch 7012 can be automatically adjusted according to temperature or pressure, with an adjustment range of 5~20cm. The working principle of this feature is as follows: when conveying larger particles, the resistance on the screw increases, the local temperature rises, the shape memory alloy undergoes a phase change, and the pitch automatically increases to accommodate the passage of large particles; when conveying smaller particles, the pitch automatically decreases to maintain a high filling rate and conveying efficiency. This adaptive adjustment requires no external sensors or controller intervention, relying entirely on the physical properties of the material itself, greatly improving the feeder's adaptability to different materials. Combined with a control system that dynamically adjusts the motor speed based on the particle size information detected by the quantum dot sensor (reducing the speed to increase torque for large particles and increasing the speed to increase the conveying capacity for small particles), the screw feeder can stably convey agricultural waste with a very wide size range (<10cm to >30cm) without human intervention, with a processing capacity of 45 tons / hour.

[0054] Furthermore, a pressure sensor is installed on the high-pressure transition chamber 707 to monitor the pressure in the high-pressure chamber and feed it back to the control system. In a preferred embodiment, a quantum dot material sensor is also installed at the feeder inlet inside the high-pressure transition chamber 7 to detect the particle size and moisture content of the material using the fluorescence properties of quantum dots. The control system dynamically adjusts the pitch and rotation speed of the screw feeder 7010 based on the detection results to achieve stable conveying of different materials.

[0055] The rest is the same as in Example 4.

[0056] Example 6: This example describes the complete working process of the multi-stage variable pressure feeding device based on the pressurized fluidized bed gasifier, based on Example 5.

[0057] (1) Feeding and pretreatment

[0058] Agricultural waste (such as wheat straw, miscellaneous wood, etc.) with a size ≤30cm and a moisture content ≤70% is fed into the atmospheric pressure pretreatment chamber 4 through the feed hopper 402. The material first passes through a horizontally laid biomimetic slime mold fiber mesh 401. This mesh, woven from modified carbon fiber with a porosity of 60%~80%, can entangle and disperse lumpy materials, preventing accumulation and bridging, and ensuring uniform distribution of the material in the central area of ​​the chamber. Subsequently, the microwave plasma pretreatment module 403, embedded in the side wall of the chamber, is activated. With a power of 5~15kW and an operating temperature of 800~1200K, it bombards the material surface with low-temperature plasma, reducing the moisture content from 70% to below 20% within 10~20 seconds, while simultaneously breaking down surface gelatinous impurities without damaging the internal combustible structure of the material. A quantum dot material sensor installed at the feed hopper 402 continuously monitors the particle size (accuracy ±0.1mm) and moisture content (accuracy ±0.1%), and the data is fed back to the control system. If the moisture content of the material is higher than the set value (15%~25%), the spring brush at the bottom of the trigger device will sweep the unqualified material back to the biomimetic slime fiber mesh 401 for reprocessing.

[0059] (2) Pressure transition

[0060] When the pretreated material accumulates to half its volume at the bottom of the atmospheric pressure pretreatment chamber 4, the first rotary sealing gate valve 5 automatically opens (opening time 1~2s). After the material falls into the intermediate pressure transition chamber 6, the first rotary sealing gate valve 5 immediately closes. The intermediate pressure transition chamber 6 is equipped with a magnetic levitation actuator: the top electromagnetic coil 601 generates a magnetic field, causing the magnetically levitated pressure-resistant conical bucket 608 to levitate in the center of the chamber, maintaining a non-contact suspension gap 607 of 0.05~0.1mm between it and the inner wall of the intermediate pressure transition chamber 604. As the material falls from above, it is dispersed and flows outwards upon encountering the suspended conical bucket, flowing downwards through the gap between the partition and the chamber wall, preventing the accumulation and blockage of fine debris. Pressure sensors within the intermediate pressure transition chamber 6 provide real-time pressure data. If the pressure fluctuation exceeds 0.1MPa, the pressure compensation unit accurately replenishes the pressure within 20ms, maintaining the intermediate pressure chamber pressure within the range of 0.5~2MPa. When the material accumulates to 1 / 3 of the volume of the intermediate-pressure transition chamber 6, the second rotary sealing gate valve 606 opens, allowing the material to enter the high-pressure transition chamber 7. Subsequently, the second rotary sealing gate valve 606 closes. The first rotary sealing gate valve 5 and the second rotary sealing valve 606 open and close alternately, with an opening and closing response time of ≤50ms, ensuring that there is no pressure leakage between the chambers.

[0061] (3) High-pressure transmission

[0062] After the material enters the high-pressure transition chamber 7, it is also affected by the magnetic levitation actuator: the electromagnetic coil 701 is energized to generate a magnetic field, which suspends the magnetically levitated pressure-resistant conical bucket 703, maintaining a levitation gap 708 of 0.05~0.1mm between it and the inner wall of the high-pressure transition chamber 707, guiding the material to fall evenly. The pressure inside the high-pressure transition chamber 7 is maintained at 1~10MPa, matching the downstream pressurized fluidized bed gasifier. After falling to the bottom of the chamber, the material enters the nickel-titanium shape memory alloy screw feeder 7010. The screw of this screw feeder is made of Ni-Ti shape memory alloy, and the screw pitch 7012 can be automatically adjusted according to temperature or pressure, with an adjustment range of 5~20cm. The control system dynamically adjusts the rotation speed of the screw feeder based on the particle size information detected by the quantum dot sensor: for particle size > 20cm, the screw pitch is 15-20cm and the rotation speed is 10-15r / min; for particle size 10-20cm, the screw pitch is 10-15cm and the rotation speed is 15-25r / min; for particle size < 10cm, the screw pitch is 5-10cm and the rotation speed is 25-50r / min. If the detected material moisture content is still higher than 20%, the control system increases the microwave plasma power by 5-10kW and extends the pretreatment time by 5 seconds. The screw feeder 7010 is driven by a motor 705 with a rotation speed of 0-50r / min and a processing capacity of 45 tons / hour. The material blowing fan 7011 is coaxially connected to the rotating shaft of the screw feeder, assisting in pushing the material to the outlet 704 and stably feeding it into the pressurized fluidized bed gasifier.

[0063] (4) Self-cleaning and monitoring

[0064] During continuous operation of the device, the ultrasonic cavitation cleaning ring 501 and shape memory alloy spring brush 502 integrated inside the first rotary sealing gate valve 5 are activated at a set cycle (e.g., once every hour, each lasting 10 seconds), forming a composite cleaning mechanism of "mechanical brushing + ultrasonic cavitation". The shape memory alloy spring brush 502 rotates synchronously with the rotating spindle, automatically adjusting the fit between the brush bristles and the sealing surface using the temperature response characteristics of the memory alloy to compensate for wear and physically remove scale and particulate impurities from the sealing surface. The ultrasonic cavitation cleaning ring 501 generates a cavitation effect at its center, enhancing the cleaning effect. A fluorescent material sensor 504 is fixedly installed next to the valve body monitoring window, collecting fluorescent signals in the sealing gap in real time to detect media leakage or residue. When leakage or excessive dirt is detected, the system immediately triggers the ultrasonic cavitation cleaning ring 501 and the shape memory alloy spring brush 502 for cleaning. The control system uses a PLC and touch screen, integrating material monitoring, pressure regulation, feed rate control, and self-cleaning trigger functions, recording data such as pressure, feed rate, energy consumption, and material parameters of each chamber every 5 minutes. When abnormal pressure occurs, the system suspends feeding; when a blockage alarm occurs, emergency cleaning is initiated (spring brush operates for 30 seconds), and if ineffective, the machine is stopped for cleaning; when energy consumption exceeds the limit, the microwave power and feeding speed are automatically matched, and the energy recovery module is checked.

[0065] (5) Shutdown operation

[0066] After stopping the feed, maintain the system until the materials in the atmospheric pressure pretreatment chamber 4 and the medium-pressure transition chamber 6 are completely emptied (confirmed by the liquid level sensor), and all the materials in the high-pressure transition chamber 7 are pushed to the gasifier. Then, shut down the screw feeder 7010. Turn off the microwave plasma pretreatment module 403, gradually reduce the power of the pressure compensation unit until shutdown, and keep the energy recovery module running until power is cut off. Release the pressure in each chamber at a rate of 0.1 MPa / min until it drops to atmospheric pressure (0.1 MPa). Finally, start the comprehensive cleaning procedure (ultrasonic + spring brush operation for 5 minutes) to remove residual materials from the chamber walls and valves, turn off the power to the control system, record the operating data and fault conditions, and complete the shutdown.

[0067] Example 7: This example tests the core performance indicators of the multi-stage variable pressure feeding device based on Example 5.

[0068] Test material: wheat straw, initial moisture content 65%, size ≤30cm.

[0069] Test Method: Material was fed into the feed chamber 402, and the device was run continuously for 2 hours. The power of the microwave plasma pretreatment module 403 was set to 12kW, the pressure of the medium-pressure transition chamber 6 to 1.2MPa, the pressure of the high-pressure transition chamber 7 to 5MPa, and the initial screw pitch of the screw feeder 7010 to 10cm and the rotation speed to 30r / min. The data acquisition system recorded parameters such as feeding efficiency, high-pressure sealing section energy consumption, and microwave dehydration time every 5 minutes. The test results are shown in the table below:

[0070] index Design Requirements Experimental results Feeding efficiency Greater than 5 tons per hour 5.2t per hour Congestion rate Less than or equal to 0.1% 0.03% Microwave dehydration time 10~20s 15s High-pressure sealing energy consumption Less than or equal to 0.5 kWh per ton 0.42 kW / hour per ton

[0071] Test results show that after 2 hours of continuous operation, the average feeding efficiency of the device is 5.2t / h, which meets the design requirements (≥5t / h); the blockage rate is 0.03%, which is lower than the design requirements (≤0.1%); the microwave dehydration time is 15s, which is within the design range (10~20s); and the energy consumption of the high-pressure sealing section is 0.42kWh / t, which is lower than the design requirements (≤0.5kWh / t).

[0072] The test results above show that the device of the present invention meets or exceeds the design specifications in terms of feeding efficiency, clogging rate, dehydration time and high pressure sealing energy consumption. In particular, the high pressure sealing energy consumption is reduced by more than 65% compared with traditional devices (usually 1.2~1.5kWh / t).

[0073] Example 8 is an adaptive feeding test for materials of different particle sizes, based on Example 5.

[0074] 50 kg each of mixed wood materials with particle sizes <10 cm, 10-20 cm, and >20 cm were fed to test the adaptive capability of the shape memory alloy screw feeder. 1. Preparation Stage: 50 kg of each of the three groups of mixed wood materials with different particle sizes was weighed to ensure uniform particle size distribution. 2. Debugging Stage: The feeder was started, initially set to a screw pitch of 10 cm and a rotation speed of 30 r / min. Formal testing began after the equipment stabilized. 3. Testing Stage: Small, medium, and large-sized mixed wood materials were sequentially fed into the feeder. During the feeding process of each group of materials, the dynamic adjustment range of the screw pitch and rotation speed, the stable feeding time, and the material blockage were recorded in real time using monitoring equipment. After each group of materials was tested, the inside of the feeder was cleaned, the next group of materials was replaced, and the above operation was repeated. 4. Replication Verification: To ensure data reliability, each experiment was repeated 3 times, and the average value was taken as the final result. The test results are shown in the table below:

[0075] Material particle size Pitch adjustment range Speed ​​adjustment range Less than 10cm 5~10cm 25~50 revolutions per minute 10~20 10~15cm 15~25 revolutions per minute Greater than 20cm 15~20cm 10-15 revolutions per minute

[0076] The results showed that for materials <10cm, the screw pitch automatically adjusted to 5~10cm, and the rotation speed was 25~50r / min; for materials 10~20cm, the screw pitch adjusted to 10~15cm, and the rotation speed was 15~25r / min; for materials >20cm, the screw pitch adjusted to 15~20cm, and the rotation speed was 10~15r / min. No blockage occurred during the entire test, indicating that the shape memory alloy screw feeder can dynamically adjust parameters according to the material particle size, adapting to the stable conveying of materials of different volumes.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some or all of the technical features thereof, within the spirit and principles of the present invention, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier, characterized in that, The system includes a multi-stage gradient pressure chamber, which consists of an atmospheric pressure pretreatment chamber (4), a medium-pressure transition chamber (6), and a high-pressure transition chamber (7) arranged sequentially from top to bottom. The pressure gradient between each chamber is achieved through a sealing and isolation mechanism. The atmospheric pressure pretreatment chamber (4) is equipped with a biomimetic slime mold fiber mesh (401) and a microwave plasma pretreatment module (403). The medium-pressure transition chamber (6) and the high-pressure transition chamber (7) are both equipped with magnetic levitation actuators. The system also includes a control system, which is electrically connected to the microwave plasma pretreatment module (403), the magnetic levitation actuators, and the sensors located in each chamber.

2. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to claim 1, characterized in that, The biomimetic slime mold fiber mesh (401) is laid horizontally inside the atmospheric pressure pretreatment chamber (4); the microwave plasma pretreatment module (403) is embedded in the side wall of the atmospheric pressure pretreatment chamber (4).

3. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to claim 2, characterized in that, The atmospheric pressure pretreatment chamber (4) is provided with a feed inlet (402) at the top; a quantum dot material sensor is installed at the feed inlet (402) to detect the particle size and moisture content of the material.

4. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to any one of claims 1 to 3, characterized in that, The sealing and isolation mechanism includes a first rotary sealing gate valve (5) and a second rotary sealing gate valve (606); the first rotary sealing gate valve (5) is located between the atmospheric pressure pretreatment chamber (4) and the medium pressure transition chamber (6); the second rotary sealing gate valve (606) is located between the medium pressure transition chamber (6) and the high pressure transition chamber (7); the first rotary sealing gate valve and the second rotary sealing gate valve (606) are opened and closed alternately.

5. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to claim 4, characterized in that, The first rotary sealing gate valve (5) includes a valve body, a rotating main shaft with a valve plate disposed in the valve body, a central cone seat coaxially connected to the rotating main shaft, and an annular mounting seat; an ultrasonic cavitation cleaning ring (501) is integrated inside or on the surface of the central cone seat; a shape memory alloy spring brush (502) is provided on the annular mounting seat, and the shape memory alloy spring brush (502) is arranged around the ultrasonic cavitation cleaning ring (501); the rotating main shaft is driven by an external motor disposed outside the valve body.

6. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to claim 5, characterized in that, The valve body is also equipped with a fluorescent material sensor (504). The fluorescent material sensor (504) is located near the monitoring window of the valve body to detect media leakage or residue in the internal dynamic sealing gap, and triggers the ultrasonic cavitation cleaning ring (501) and the shape memory alloy spring brush (502) to perform cleaning.

7. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to any one of claims 1 to 3, 5 and 6, characterized in that, The medium-pressure transition chamber (6) includes a medium-pressure transition chamber body (604) and an electromagnetic coil (601) located on the top of the medium-pressure transition chamber body (604). The medium-pressure transition chamber body (604) is equipped with a magnetically levitated pressure-resistant conical bucket (608). The magnetically levitated pressure-resistant conical bucket (608) generates a levitation magnetic field through the electromagnetic coil (601) and maintains a levitation gap (607) that does not contact the inner wall of the medium-pressure transition chamber body (604).

8. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to claim 7, characterized in that, The high-pressure transition chamber (7) includes a high-pressure transition chamber body (707) and an electromagnetic coil two (701) located on the top of the high-pressure transition chamber body (707). The high-pressure transition chamber (7) is equipped with a magnetically levitated pressure-resistant conical bucket two (703). The magnetically levitated pressure-resistant conical bucket two (703) generates a levitation magnetic field through the electromagnetic coil two (701) and maintains a non-contact levitation gap two (708) with the inner wall of the high-pressure transition chamber body (707).

9. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to claim 8, characterized in that, The bottom of the high-pressure transition chamber (707) is provided with a screw feeder (7010), one end of which is connected to a motor (705), and a material blowing fan (7011) is coaxially connected to the rotating shaft of the screw feeder (7010).

10. The multi-stage variable pressure feeding device based on a pressurized fluidized bed gasifier according to any one of claims 1 to 3, 5, 6, 8 and 9, characterized in that, The pressure gradients of the multi-stage gradient pressure chambers are as follows: the atmospheric pressure pretreatment chamber (4) is at atmospheric pressure, the medium pressure transition chamber (6) is at 0.5~2MPa, and the high pressure transition chamber (7) is at 1~10MPa.

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