Joule heat solid distillation apparatus

Abstract

In order to solve the problems of low temperature, poor efficiency and inconvenient operation of solid mixture separation, the utility model provides a solid distillation device of joule heat effect, through short time high current power -on generates joule heat high temperature, directly leads to the gasification or decomposition of solid material, simultaneously in the top collection light component gas and bottom collection heavy component gas, has realized the effective separation of solid mixture. The device has high heating temperature, short heating time and high separation efficiency, and can be replaced with different size reaction tubes according to the need, and meets the needs of laboratory and industrial application.

Description

Technical Field

[0001] This utility model belongs to the technical field of solid material separation and purification equipment, specifically relating to a device that achieves solid gasification separation and multi-fraction collection through Joule heating. Background Technology

[0002] The basic principle of Joule heating is that heat is generated when an electric current passes through a conductor. This phenomenon was discovered by British physicist James Joule in 1841 and is therefore called "Joule heating." In recent years, researchers have applied this principle to the field of rapid electric heating, generating high temperatures (up to 3000°C or higher) through a large current for a short time, a process known as "rapid Joule heating." The mixture heated to this high temperature vaporizes or decomposes, potentially enabling the separation of different components of a solid substance.

[0003] In 2021, Rice University designed a miniature Joule heating distillation apparatus, which uses a small quartz tube sealed with an O-ring to achieve Joule heating, with a cold trap connected below the quartz tube to collect the distillation products (Nature Communications, Vol. 12, No. 5794). Although this Joule heating provides a new process route for the distillation of solid mixtures, current Joule heating distillation apparatuses generally have low throughput and difficult product collection due to technical limitations such as the need for hollow electrodes to allow gas to escape and the fact that solid mixtures are generally non-conductive. This makes it difficult to meet the needs of laboratory and industrial production. In particular, Joule heating distillation apparatuses have three problems: first, the O-ring is only heat-resistant up to 300 °C, while Joule heating typically ranges from 800 to 3000 °C, so the O-ring is easily burned out during the Joule heating process; second, the reaction tube volume is too small, and excessive volatiles and gases can cause the quartz tube to burst and explode; third, it can only collect heavy volatiles such as heavy metal compounds, and cannot collect lighter volatiles, thus failing to meet the purpose of distillation. Utility Model Content

[0004] This invention aims to provide a Joule thermal solid distillation apparatus that uses Joule thermal heating to rapidly decompose or vaporize solid materials. Based on the density differences of the vaporized components, light components are directionally enriched in the top collection zone, while heavy components are efficiently deposited in the bottom collection zone, thereby achieving precise separation of multiple fractions or components.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A Joule thermal solid distillation apparatus includes a support base, a graphite bottom plate, a graphite top plate, ceramic screws, an insulating reaction tube, a tubular heating element, an infrared temperature probe, a top funnel, a bottom funnel, and a conical flask. The apparatus consists of a graphite base plate placed on an insulated support base; the graphite base plate and graphite top plate are fixed together with ceramic screws to form a rigid frame, while maintaining insulation between them; an insulated reaction tube is embedded in the center of the graphite base plate and graphite top plate; the solid reactant to be distilled is placed inside the insulated reaction tube, and the outer wall of the reaction tube tightly wraps the heating element, with the upper and lower ends of the heating element fixedly connected to the graphite base plate and graphite top plate, respectively; a bottom funnel is located on the insulated reaction tube, and a top funnel is inverted on top of the bottom funnel to form a relatively sealed cavity for collecting the distilled light components; a conical flask is located below the insulated reaction tube, and a hollow graphite plug is used to support the solid reactant between the conical flask and the reaction tube, ensuring that the distilled heavy component gas can pass through the graphite plug and enter the conical flask; an infrared temperature probe is aimed at the center of the heating element to measure its Joule temperature. The entire solid distillation apparatus is placed inside a vacuum chamber, with the graphite base plate and graphite top plate connected to the positive and negative terminals of a DC power supply to generate Joule heat.

[0007] The reaction tube can be made of quartz, alumina, zirconium oxide, boron nitride, or silicon carbide.

[0008] The heating element can be graphite felt, graphite paper, silicon carbide, or tungsten wire.

[0009] The bottom of the inner wall of the bottom funnel has a ring of lower baffles.

[0010] This utility model has the following beneficial effects: (1) When Joule heat is generated by electricity, the temperature rises rapidly, the solid reactants begin to vaporize or decompose, the less dense gaseous components evaporate upwards, condense in the top funnel, and are collected in the bottom funnel. Due to the presence of the baffle in the bottom funnel, they remain in the bottom funnel; the more dense gaseous components pass through the hollow graphite plug below and are deposited in the conical flask below. (2) After distillation at one temperature is completed, the upper funnel cavity and the lower conical flask can be easily replaced to continue collecting components at higher temperatures. By repeating this process multiple times, light and heavy components at different temperatures can be collected, achieving continuous separation of multiple components. (3) Conductive or non-conductive solid materials can be added to the reaction tube. For non-conductive materials, external graphite felt can be used for heat conduction to assist heating, expanding the applicability of this equipment. (4) The size of the reaction tube can be changed according to needs, and its specifications and size can be adjusted according to actual needs to flexibly realize distillation operations of different processing scales and meet various application scenarios of experimental and pilot-scale. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of a Joule thermal solid distillation apparatus proposed in this utility model.

[0012] Legend:

[0013] 1. Support base; 2. Graphite base plate; 3. Graphite top plate; 4. Ceramic screw; 5. DC power supply; 6. Reaction tube; 7. Heating element; 8. Solid reactant; 9. Infrared temperature probe; 10. Hollow graphite plug; 11. Conical flask; 12. Top funnel; 13. Bottom funnel; 14. Bottom funnel baffle; 15. Vacuum chamber. Detailed Implementation

[0014] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0015] In the following implementation examples, unless otherwise specified, the experimental methods mentioned refer to conventional experimental methods. Similarly, the raw materials used can be purchased commercially unless specific requirements are specified. It should be noted that the power supply used in this embodiment is a 40 kW DC power supply, the voltage and current of which are adjustable, with a maximum voltage of 100V and a maximum current of 400A.

[0016] like Figure 1 As shown, the Joule thermal solid distillation apparatus provided in this embodiment includes: a support base 1, a graphite bottom plate 2, a graphite top plate 3, a ceramic screw 4, a DC power supply 5, a reaction tube 6, a heating element 7, a solid reactant 8, an infrared temperature probe 9, a hollow graphite plug 10, a conical collecting flask 11, a top funnel 12, a bottom funnel 13, a small baffle 14 inside the bottom funnel, and a vacuum chamber 15.

[0017] The graphite base plate 2 and graphite top plate 3 each have four smooth through holes. Four ceramic screws 4 pass through these two graphite plates and are secured with nuts to form a rigid support structure. The graphite base plate 2 and graphite top plate 3 also each have three screw holes for mounting the heating element 7, fixing the heating element around the reaction tube. The reactant powder 8 to be distilled is placed in the centrally located reaction tube 6. The heating current required by this device is provided by a DC power supply 5.

[0018] The current flows through the electrodes of the graphite bottom plate 2 into the heating element 7, which is tightly wrapped around the outer wall of the reaction tube, and then flows back to the DC power supply 5 through the electrodes of the graphite top plate 3, forming a closed circuit. When energized, the heating element 7 generates Joule heat, and the resulting high-temperature heat is conducted through the tube wall to the reactant powder 8 inside, causing it to vaporize or decompose under high temperature. During the reaction, the light components migrate along the upper airflow and condense and accumulate in the baffled quartz funnel 13 and glass funnel 12, while the heavy components are introduced by gravity through the hollow graphite plug 10 and settle into the conical flask 11 at the bottom.

[0019] In terms of the specific assembly structure, the graphite base plate and top plate measure 150 mm × 100 mm × 20 mm. Four 16 mm diameter through holes are drilled 20 mm from each corner to accommodate 16 mm diameter, 110 mm long ceramic screws 4, thus achieving a fixed connection between the two plates. Each of the graphite top and base plates has a 14 mm diameter through hole in its center for connecting the insulating reaction tube 6 to the quartz funnel 13. The top and base plates also have 10 mm diameter, 30 mm deep screw holes for connecting the positive and negative terminals of the power supply. Additionally, two 6 mm diameter, 21 mm deep screw holes are drilled, and the heating element is fixed using two 80 mm × 20 mm × 5 mm graphite pressure plates. The graphite base plate also has an 18 mm diameter through hole in its center for connecting the reaction tube, the graphite hollow plug, and the conical flask.

[0020] The heating element 7 is a commercially available graphite felt measuring 100 mm × 94 mm × 3 mm, while the insulating reaction tube is a boron nitride tube with an inner diameter of 16 mm, an outer diameter of 22 mm, and a length of 60 mm. The graphite felt tightly wraps around the outer wall of the boron nitride tube and is firmly pressed and fixed by upper and lower graphite pressure plates. A graphite hollow plug 10 is connected to the lower end of the reaction tube, and a 13 mm diameter stainless steel sintered mesh is placed on top of it to prevent the reaction raw materials from settling into the collection chamber. The other end of the graphite hollow plug is connected to the conical flask 11 at the bottom to receive the settled heavy component products. The entire device, from top to bottom, consists of a graphite top plate, ceramic screws, a boron nitride reaction tube, graphite felt, a graphite bottom plate, a graphite hollow plug, and a conical flask, exhibiting a stable and compact structure.

[0021] After assembly, the entire device is placed inside a vacuum chamber 14 measuring 400 mm × 400 mm × 500 mm. A 1 g fly ash sample is added through the central hole of the graphite top plate, and a quartz funnel 13 and a glass funnel 12 are assembled to form the top condensation module. The graphite felt used has a resistance of 2.5 Ω, and the system is equipped with a matching infrared temperature probe 9, with a temperature measurement range of 400-3600℃. The probe is positioned behind the graphite felt, aligned with the heating area, to achieve non-contact temperature monitoring. Thus, the assembly of the Joule thermal solid-state distillation apparatus is complete.

[0022] During operation, a vacuum was first applied to -0.098 MPa, the output voltage was adjusted to 60 V and the current to 170 A, and the heating element temperature reached 2800 ℃, which was maintained for 10 seconds. During the reaction, condensed products were continuously collected in the quartz funnel and conical flask. After the reaction was completed, the collection components were removed, and 0.5 g of distilled product was collected in the top and bottom funnels, and 0.02 g of distilled product was collected in the conical flask.

[0023] In summary, the Joule thermal solid distillation apparatus provided in this embodiment has the advantages of compact structure, precise temperature control, short separation time, and high efficiency. It can efficiently realize rapid distillation and bidirectional collection of multiple fractions, providing a reliable apparatus solution for high-temperature fractionation of solid materials.

[0024] The above description is merely one embodiment of this utility model and is not intended to limit the patent scope of this utility model. Any equivalent structural or procedural modifications made based on the content of this utility model specification, or direct or indirect applications in other related technical fields, shall fall within the patent protection scope of this utility model.

Claims

1. A Joule thermal solid distillation apparatus, characterized in that, The system includes a support base, a graphite base plate, a graphite top plate, ceramic screws, an insulating reaction tube, a tubular heating element, an infrared temperature probe, a top funnel, a bottom funnel, and a conical flask. The graphite base plate rests on the insulating support base. The graphite base plate and top plate are fixed together with ceramic screws to form a rigid frame, maintaining insulation between them. The insulating reaction tube is embedded in the center of the graphite base plate and top plate. The solid reactant to be distilled is placed inside the insulating reaction tube, and the heating element is tightly wrapped around the outer wall of the tube. The upper and lower ends of the heating element are fixedly connected to the graphite base plate and top plate, respectively. The bottom funnel is located on the insulated reaction tube, and the top funnel is inverted on top of the bottom funnel to form a relatively sealed cavity for collecting the distilled light components. The conical flask is located below the insulated reaction tube, and a hollow graphite plug is used between the conical flask and the reaction tube to support the solid reactants and ensure that the distilled heavy component gas can pass through the graphite plug and enter the conical flask. An infrared temperature probe is aimed at the middle of the heating element to measure the Joule temperature of the heating element. The entire solid distillation apparatus is placed in a vacuum chamber, and the graphite bottom plate and graphite top plate are connected to the positive and negative terminals of a DC power supply to generate Joule heat.

2. The Joule thermal solid distillation apparatus according to claim 1, characterized in that, The reaction tube is made of quartz, alumina, zirconium oxide, boron nitride, or silicon carbide.

3. The Joule thermal solid distillation apparatus according to claim 1, characterized in that, The heating element is made of graphite felt, graphite paper, silicon carbide, or tungsten wire.

4. The Joule thermal solid distillation apparatus according to claim 1, characterized in that, The bottom of the inner wall of the bottom funnel has a ring of lower baffles.

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