Material conveying and drying integrated system based on field energy coupling

Abstract

The application relates to a material conveying and drying integrated system based on field energy coupling, belonging to the technical field of material drying and conveying. The system comprises a flexible composite conveying belt, an electromagnetic-microwave composite heating module and an ORC power generation system. The flexible composite conveying belt is composed of a graphene base material layer and a piezoelectric ceramic surface layer. A memory alloy hinge is located in the graphene base material layer. An FBG sensor optical fiber is embedded in the neutral axis plane of the graphene base material layer. Through the synergistic effect of an electromagnetic field and a microwave field and waste heat power generation, the water content of the material is reduced to below 5%, and the comprehensive energy efficiency ratio of the system is greater than or equal to 2.0. The system combines organic Rankine cycle (ORC) power generation technology, realizes efficient material drying and energy recovery, and is suitable for green conveying of high-moisture coal slime, copper concentrate and the like.

Description

Technical Field

[0001] This utility model belongs to the field of bulk material conveying technology, and specifically relates to an integrated material conveying and drying system based on field energy coupling. Background Technology

[0002] The existing technology has the following drawbacks: 1. Traditional hot air drying systems have high energy consumption, thermal efficiency of less than 40%, and uneven temperature distribution can easily lead to material carbonization; 2. Single electromagnetic or microwave heating technologies have poor drying effects on heterogeneous materials due to insufficient energy penetration depth; 3. The waste heat recovery system is separated from the drying equipment, resulting in an overall energy efficiency ratio (COP) of less than 1.5 and low energy utilization. Summary of the Invention

[0003] Based on the above-mentioned shortcomings, this utility model proposes an integrated material conveying and drying system and control method based on field energy coupling. By combining composite field energy coupling with ORC waste heat power generation technology, the drying efficiency and energy utilization rate are greatly improved.

[0004] The technical solution of this utility model is: an integrated material conveying and drying system based on field energy coupling, the key technical points of which include: Flexible composite conveyor belt: The flexible composite conveyor belt 1 is driven by drive rollers at both ends. The flexible composite conveyor belt is composed of a graphene substrate layer and a piezoelectric ceramic surface layer. The shape memory alloy hinge is located inside the graphene substrate layer. The axis of the shape memory alloy hinge is perpendicular to the running direction of the conveyor belt. The two ends of the shape memory alloy hinge are fixed to the graphene substrate layer by laser micro-welding. The FBG sensor optical fiber is embedded in the neutral axis plane of the graphene substrate layer. The optical fiber of the FBG sensor passes through the microchannel on the shape memory alloy hinge and is fixed by high-temperature silicone adhesive. Electromagnetic-microwave composite heating module: includes an electromagnetic induction coil array and a microwave resonant cavity. The electromagnetic induction coil array is placed on an insulating support directly below the flexible composite conveyor belt. The microwave resonant cavity is located downstream of the electromagnetic induction coil array and has a cavity through which the flexible composite conveyor belt passes. The cavity forms a three-dimensional surrounding structure in a local area of ​​the flexible composite conveyor belt. The top of the cavity is separated from the surface of the flexible composite conveyor belt by a distance that satisfies the requirement of uniform microwave field coverage of the material. The microwave resonant cavity is aligned with the center line of the electromagnetic coil array. The ORC power generation system includes an evaporator, which is connected to the exhaust port of the microwave resonant cavity via a waste heat recovery pipeline. The evaporator outlet is connected to a turbine, which is connected to a condenser via a pipeline. The condenser is connected to the working fluid pump of the turbine via a pipeline, and the working fluid pump of the turbine is connected to the evaporator in a closed loop. The multi-sensor feedback controller is connected to the FBG sensor, magnetron, evaporator, and turbine.

[0005] In the above scheme, the deformation recovery rate of the shape memory alloy hinge is ≥98%, and the spacing is 150-250mm.

[0006] In the above scheme, the dynamic adjustment range of the power ratio of the electromagnetic field and the microwave field is 1:0.5-1:2.

[0007] In the above scheme, each FBG sensor is arranged at equal intervals along the longitudinal direction of the conveyor belt, with a spacing of 0.5-1.5m.

[0008] The beneficial effects of this utility model are as follows: This utility model provides an integrated material conveying and drying system based on field energy coupling, including a flexible composite conveyor belt, an electromagnetic-microwave composite heating module and an ORC power generation system. Through the synergistic effect of electromagnetic field and microwave field and waste heat power generation, the moisture content of the material is reduced to below 5%, and the system's comprehensive energy efficiency ratio is ≥2.0. Combined with Organic Rankine Cycle (ORC) power generation technology, it realizes efficient material drying and energy recovery, and is suitable for green conveying in scenarios such as high moisture content coal slime and copper concentrate. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram of the overall system structure; Figure 2 This is a schematic diagram of the electromagnetic-microwave composite heating field distribution; Figure 3 Here is a flow chart of the working fluid circulation in the ORC power generation system; The numbers in the diagram are as follows: 1-Flexible composite conveyor belt, 11-Graphene substrate layer, 12-Piezoelectric ceramic layer, 13-Memory alloy hinge, 14-FBG sensor; 2-Electromagnetic induction coil array, 21-High frequency power supply module; 3-Microwave resonant cavity, 31-Magnetron; 4-ORC power generation system; 41-evaporator; 42-turbine; 43-condenser; 5-waste heat recovery pipeline; 6-multi-sensor feedback controller; 7-bottom support. Detailed Implementation

[0011] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the following description is provided in conjunction with the appendix. Figure 1-3 The present invention will be further described in detail below with reference to specific embodiments.

[0012] This embodiment of the integrated material conveying and drying system based on field energy coupling includes a flexible composite conveyor belt 1, which runs horizontally through the entire system. Both ends are driven by drive rollers, and support rollers are installed below. The bottom layer of the flexible composite conveyor belt is a graphene substrate layer 11 with a thickness of 0.3-0.8 μm, providing support and thermal conductivity. The surface layer is a piezoelectric ceramic layer 12 with a thickness of 0.1-0.3 mm, which directly contacts the material and enhances heat transfer efficiency. Segmented shape memory alloy hinges 13 are located inside the graphene substrate layer 11, with a spacing of 150-250 mm. They can withstand high-temperature deformation below 200°C. The hinge axis is perpendicular to the running direction of the flexible composite conveyor belt 1. The two ends of the shape memory alloy hinges 13 are fixed to the graphene substrate 11 by laser micro-welding (weld point diameter ≤ 0.5 mm), allowing the flexible composite conveyor belt 1 to automatically bend / recover with temperature changes. An FBG sensor 14 is embedded in the neutral axis plane of the graphene substrate layer 11, with the neutral axis plane 0.15-0.25 mm from both the upper and lower surfaces. The FBG sensor 14 is arranged longitudinally along the conveyor belt, with a temperature detection accuracy of ±0.5℃ and a strain detection accuracy of ±5με. The optical fiber of the FBG sensor 14 passes through the microchannel reserved in the shape memory alloy hinge 13 and is fixed with high-temperature silicone. The signal line of the FBG sensor 14 is led out from the side to the controller 6. An electromagnetic induction coil array 2 is placed on an insulating support 50-100 mm directly below the flexible composite conveyor belt 1. The insulating support is welded to the bottom support 7 of the flexible composite conveyor belt 1 and is driven by a high-frequency power module 21 (operating frequency 10kHz–1MHz), with a power density of 2-5kW / m², used to induce eddy current heating inside the material. A microwave resonant cavity 3 is located downstream of the electromagnetic induction coil array 2, with a dual-frequency design (915MHz and 2.45GHz), a power density of 1-3kW / m³, and penetrates non-polar molecules to achieve bulk heating. The microwave resonant cavity 3 is placed on the ground via its built-in support. The cavity of the microwave resonant cavity 3 encloses the top and sides (bottom open) of the flexible composite conveyor belt 1, forming a three-dimensional surrounding structure in a localized area. The top of the cavity is 80-120mm from the surface of the conveyor belt 1, ensuring uniform microwave field coverage of the material. The bottom of the microwave resonant cavity 3 is open, with a gap of ≤5mm between it and the flexible composite conveyor belt 1 (sealed with a metal brush to prevent leakage), and is aligned with the centerline of the electromagnetic induction coil array 2, with a deviation of ≤±2mm (laser calibration). The magnetron 31 is installed on the side wall of the cavity and feeds microwaves (dual-frequency 915MHz / 2.45GHz) through a waveguide. The induction coil array 2 induces eddy current heating below the flexible composite conveyor belt 1, while the microwave resonant cavity 3 forms a three-dimensional heating field. This dual-field coupling solves the problem of insufficient penetration depth in traditional drying methods.

[0013] The ORC power generation system 4 in this embodiment includes an evaporator 41, a turbine 42, and a condenser 43. The turbine should be selected with a rotational speed of 2000-4000 rpm and a power generation efficiency of ≥15%. The evaporator 41 is connected to the exhaust port of the microwave resonant cavity 3 through a waste heat recovery pipeline 5 to preheat the fresh air temperature to 45-55℃. The turbine 42 is directly flange-connected to the outlet of the evaporator 41. The condenser 43 is located downstream of the turbine 42 and is connected to the pump of the turbine 42 in a closed loop through a pipeline. The multi-sensor feedback controller 6 is an independent control cabinet that receives signals from the FBG sensor 14 and outputs commands to the power supply 21, the magnetron 31, and the ORC power generation system 4.

[0014] The workflow of the integrated material conveying and drying system based on field energy coupling in this embodiment is as follows: First, the electromagnetic field rapidly heats the metallic impurities; then, 915MHz microwaves penetrate the high-moisture material; when the moisture content drops below 15%, 2.45GHz precision dehydration is switched on; the humid and hot exhaust gas is recovered by the ORC system to generate electricity; finally, dried material with a moisture content of <5% is output. This process design takes into account the staged characteristics of the material dehydration process. Feeding: Wet materials (such as coal slime with high moisture content) enter from the left end of conveyor belt 1.

[0015] Primary heating: When passing above the electromagnetic induction coil array 2, the metallic impurities in the material generate eddy currents due to electromagnetic induction, which rapidly heats the surface and shallow layers of the material (eddy current effect). At the same time, the microwave resonant cavity 3 penetrates the interior of the material (non-polar molecules, such as water molecules) at 915MHz, converting electromagnetic energy into heat energy through dielectric loss, thereby achieving uniform heating inside the material.

[0016] Secondary heating: After the moisture content drops to 15%, the microwave switches to 2.45GHz for precise dehydration, and the electromagnetic field power is reduced (power ratio 1:1).

[0017] Waste heat recovery: The hot and humid waste gas is drawn into the waste heat pipeline 5 and releases heat in the ORC evaporator 41.

[0018] Discharge: The dried material (moisture content <5%) is discharged from the right end of the conveyor belt.

[0019] The system in this embodiment can also be further closed-loop controlled using a controller: for example, the FBG sensor 14 monitors temperature / strain in real time, and the controller 6 dynamically adjusts for temperature deviation and strain anomalies. This part can be implemented through a control algorithm, and subsequent control can be set by those skilled in the art as needed. It is not included in the protection scope of this embodiment and will not be described in detail.

[0020] Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A material conveying and drying integrated system based on field energy coupling, characterized in that, include: Flexible composite conveyor belt: The flexible composite conveyor belt is driven by drive rollers at both ends. The flexible composite conveyor belt is composed of a graphene substrate layer and a piezoelectric ceramic surface layer. The shape memory alloy hinge is located inside the graphene substrate layer, and the axis of the shape memory alloy hinge is perpendicular to the running direction of the conveyor belt. The two ends of the shape memory alloy hinge are fixed to the graphene substrate layer by laser micro-welding. The FBG sensor optical fiber is embedded in the neutral axis plane of the graphene substrate layer. The optical fiber of the FBG sensor passes through the microchannel on the shape memory alloy hinge and is fixed by high-temperature silicone adhesive. Electromagnetic-microwave composite heating module: includes an electromagnetic induction coil array and a microwave resonant cavity. The electromagnetic induction coil array is placed on an insulating support directly below the flexible composite conveyor belt. The microwave resonant cavity is located downstream of the electromagnetic induction coil array and has a cavity through which the flexible composite conveyor belt passes. The cavity forms a three-dimensional surrounding structure in a local area of ​​the flexible composite conveyor belt. The top of the cavity is separated from the surface of the flexible composite conveyor belt by a distance that satisfies the requirement of uniform microwave field coverage of the material. The microwave resonant cavity is aligned with the center line of the electromagnetic coil array. The ORC power generation system includes an evaporator, which is connected to the exhaust port of the microwave resonant cavity via a waste heat recovery pipeline. The evaporator outlet is connected to a turbine, which is connected to a condenser via a pipeline. The condenser is connected to the working fluid pump of the turbine via a pipeline, and the working fluid pump of the turbine is connected to the evaporator in a closed loop. The multi-sensor feedback controller is connected to the FBG sensor, magnetron, evaporator, and turbine.

2. The integrated material conveying and drying system based on field energy coupling according to claim 1, characterized in that: The shape memory alloy hinge has a deformation recovery rate of ≥98% and a spacing of 150-250mm.

3. The integrated material conveying and drying system based on field energy coupling according to claim 1, characterized in that: The dynamic adjustment range of the power ratio between the electromagnetic field and the microwave field is 1:0.5-1:

2.

4. The integrated material conveying and drying system based on field energy coupling according to claim 1, characterized in that: Each FBG sensor is arranged at equal intervals along the longitudinal direction of the conveyor belt, with a spacing of 0.5-1.5m.

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