Apparatus for heating volatile matter-containing powder by using joule heating, and heating method

Abstract

Provided in the present invention are an apparatus for heating volatile matter-containing powder by using Joule heating, and a method. A first electrode tip and a second electrode tip are both vertically arranged, a chamber for placing volatile matter-containing powder into is disposed on a second electrode, the first electrode tip is located above the second electrode tip, and the first electrode tip may be pressed tightly onto the volatile matter-containing powder in the chamber. The method comprises the steps of: controlling a first electrode tip to press tightly onto volatile matter-containing powder; performing power-on, such that the first electrode tip, the volatile matter-containing powder and a second electrode tip form a conductive path; and monitoring the temperature of the volatile matter-containing powder in real time, and when the temperature of the volatile matter-containing powder reaches a target temperature, immediately controlling the power-on loop to power off, and then immediately controlling the first electrode tip to snap open. The present invention can significantly prolong the self-conducting time of a volatile matter-containing powder material during heating, and can stably and quickly heat the volatile matter-containing powder material, such that the volatile matter-containing powder material is heated more sufficiently, thereby improving the heating rate of the volatile matter-containing powder material, and enhancing the effect of the interaction between a volatile matter and a powder matrix.

Description

Device and method for heating powder containing volatile components using Joule heat Technical Field

[0001] The invention belongs to the technical field of processing powder materials containing volatile components, and particularly relates to a device and a heating method for heating powder containing volatile components by utilizing Joule heat. Background Art

[0002] Using Joule heat to treat rubber and organic matter to quickly and efficiently transform them into high-value-added products is an advanced Joule heat processing material technology. It has great advantages especially for volatile powders that continuously form films before treatment and remain attached to or close to the heat source after heat treatment.

[0003] The core of Joule heat processing technology is the self-heating of the product upon application of electricity. The faster the temperature rises, the better the treatment effect. However, for powder materials that cannot be attached to a heat source and contain volatile components, the treatment effect is poor. One of the main reasons is that the positive and negative electrode rods are fixed and parallel to the horizontal plane. When the material is heated to the vaporization temperature of the volatile components due to self-heating during application of electricity, the volatile components quickly escape, causing the powder material to become fluffy before heat treatment, increasing its resistance and thus rapidly reducing the temperature rise rate. After that, the powder material relies on heat generation from the heat source and heat transfer to maintain or increase the powder material temperature, rather than the Joule heat generated by the power supply to maintain or maintain the material temperature.

[0004] In the prior art, document CN116943569A discloses an apparatus for flash-heating pulverized coal to produce olefins. The apparatus comprises a pulse power supply and a reaction chamber. The apparatus also includes electrodes connected to the positive and negative electrodes of the pulse power supply, with their ends distal to the pulse power supply extending into the reaction chamber to form an electric field. The reaction chamber is also equipped with a conveying mechanism capable of forming airflow channels along its inner and outer surfaces. However, this solution still utilizes the typical horizontal arrangement of the positive and negative electrodes, which is still not conducive to stable and rapid heating of volatile-containing powder materials and is unable to effectively extend the self-conducting time of the volatile-containing powder materials during heating. Summary of the Invention

[0005] In order to at least effectively prolong the self-conductivity time of the volatile-containing powder material during the heating process, the present invention provides a device and a heating method for heating the volatile-containing powder using Joule heat.

[0006] The present invention adopts the following technical solutions.

[0007] A device for heating volatile powder using Joule heat includes a first electrode head and a second electrode head. The first electrode head and the second electrode head are both arranged vertically. A chamber for placing the volatile powder is provided on the second electrode head. The first electrode head is located above the second electrode head. The first electrode head can be pressed tightly against the volatile powder in the chamber. During the power-on process, the current flows vertically through the volatile powder and self-conducts and self-heats the volatile powder. The first electrode head can also move upward at a set time.

[0008] In order to heat the volatile powder material more stably and quickly, the surface of the electrode head in contact with the volatile powder is a horizontal surface.

[0009] As a preferred solution, the chamber is an open groove-shaped structure.

[0010] As a preferred solution, the first electrode head can be loosely fitted in the chamber, and the loose fit is no greater than 5 mm.

[0011] Furthermore, the first electrode head is connected to an actuator, which is used to control the first electrode head to quickly spring upward at a set time. The actuator is also used to control the first electrode head to be pressed down according to a set pressure.

[0012] Furthermore, a temperature monitoring system is included, which is used to monitor and provide feedback on the temperature of the volatile powder in the chamber in real time.

[0013] In the present invention, during the power-on process, the volatile powder is always in a compacted state.

[0014] A heating method for the aforementioned device for heating volatile powder using Joule heat comprises the following steps: step 1, adding volatile powder into a chamber when the first electrode head is in a pop-up state; step 2, controlling the first electrode head to press downward according to a set pressure so that the first electrode head is pressed tightly against the volatile powder; step 3, applying power so that the first electrode head, the volatile powder, and the second electrode head form a conductive path; step 4, monitoring the temperature of the volatile powder in real time, and when the temperature of the volatile powder reaches the target temperature, immediately controlling the power circuit to be de-energized, and immediately controlling the first electrode head to pop up.

[0015] As a preferred solution, the volatile powder is acidified graphite with a particle size of 15-30 microns.

[0016] Beneficial effects: The present invention can significantly prolong the self-conductivity time of volatile-containing powder materials during the heating process, can stably and quickly heat-treat volatile-containing powder materials, so that the volatile-containing powder materials are heated more fully, and the heating rate of the volatile-containing powder materials is improved; by adopting the scheme of the present invention, it is possible to ensure that the current is conducted in the material before the volatiles of the volatile-containing powder materials escape and before the target temperature is reached, thereby avoiding the disadvantages of indirect heating treatment of powder materials in the existing method. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] [Corrected 16.06.2025 according to Rule 91] Figure 1 is a schematic diagram of the electrode device for heating volatile-containing powder using Joule heat in Example 1. [0017.1][Corrected 16.06.2025 according to Rule 91] Figure 2 is a high-resolution transmission microscope image of the sample prepared in Example 1. [0017.2] [Corrected 16.06.2025 according to Rule 91] Figure 3 is a high-resolution transmission microscope image of the sample prepared in Example 2. [0017.3] [Corrected 16.06.2025 according to Rule 91] Figure 4 is a high-resolution transmission microscope image of the sample prepared in Example 6. [0017.4] [Corrected 16.06.2025 according to Rule 91] Figure 5 is a transmission microscope image of a carbon powder raw material - a few-layer graphene sample. DETAILED DESCRIPTION

[0018] The following is a clear and complete description of the technical solutions of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0019] As shown in Figure 1, a device for heating volatile powder using Joule heat includes a first electrode head 1 and a second electrode head 3. The electrode heads are made of silicon carbide ceramics. The first electrode head 1 and the second electrode head 3 are arranged vertically. A chamber for placing volatile powder 2 is provided on the second electrode. The first electrode head 1 is located above the second electrode head 3. The first electrode head 1 can be pressed on the volatile powder 2 in the chamber, and during the power-on process, the volatile powder 2 is always in a compressed state. The current flows through the volatile powder 2 in a vertical direction and self-conducts and self-heats the volatile powder 2. The first electrode head 1 can also move upward at a set time. Among them, the surface of the electrode head in contact with the volatile powder 2 is a horizontal plane, and the chamber is an open groove structure; the first electrode head 1 can be loosely fitted in the chamber, and the fitting gap is not greater than 5 mm; the first electrode head 1 is connected to an actuator, which is used to control the first electrode head 1 to quickly bounce upward at a set time, and the actuator is also used to control the first electrode head 1 to be pressed down according to a set pressure; it also includes a temperature monitoring system, which is used to monitor and feedback the temperature of the volatile powder 2 in the chamber in real time.

[0020] A heating method for a device for heating volatile powder using Joule heat in this embodiment includes the following steps: Step 1, adding volatile powder 2 into a chamber when a first electrode head 1 is in a pop-up state; Step 2, controlling the first electrode head 1 to be pressed downward according to a set pressure so that the first electrode head 1 is pressed tightly against the volatile powder 2; Step 3, applying power so that the first electrode head 1, the volatile powder 2, and the second electrode head 3 form a conductive path; Step 4, real-time monitoring of the temperature of the volatile powder 2, and when the temperature of the volatile powder reaches the target temperature, immediately controlling the power circuit to be de-energized, and immediately controlling the first electrode head 1 to pop open.

[0021] In Example 1, we used heated acidified graphite (particle size 15-30 microns) as an example: using the conventional heating method (two horizontally arranged electrode heads with graphite located between them, power of 1600W, and a graphite layer thickness of 4mm), heating to the target temperature (650°C) took 18 seconds and consumed 28.8kJ of energy. Using the heating scheme in this example (power of 900W, a graphite layer thickness of 4mm), heating to the target temperature took only 23 seconds and consumed 20.7kJ of energy. In comparison, the heating efficiency in this scheme was significantly improved, and the heating process was more stable.

[0022] [Corrected 16.06.2025 according to Rule 91] Example 2: 0.25 g of a ball-milled mixed powder sample of sodium hydroxide and few-layer graphene powder was prepared at a mass ratio of 1:3.33. The sample tube was placed horizontally, with the positive and negative electrodes facing each other horizontally. The heating power and time were 2100 W and 20 s, respectively. The maximum abundance (dV / dD) of the graphene micropores obtained by acid washing and drying was 0.0345 cm3 ·g -1 nm -1 , the specific surface area is 927.36m 2 / g.

[0023] [Corrected 16.06.2025 according to Rule 91] Example 3: 0.25 g of a ball-milled mixed powder sample of sodium hydroxide and few-layer graphene powder was used as an example, with a mass ratio of 1:3.33. The sample tube was placed vertically, with the electrodes facing each other, and the powder sample sandwiched between them. The heating power and time were 2100 watts and 15 seconds, respectively. A spring was used to apply a 1.02 mm extension force to the top of the upper electrode. The maximum abundance (dV / dD) of the graphene micropores obtained by acid washing and drying was 0.0296 cm 3 ·g -1 nm -1 , the specific surface area is 916.23m 2 / g.

[0024] [Corrected 16.06.2025 according to Rule 91] Example 4: 0.25 g of a ball-milled mixed powder sample of sodium hydroxide and few-layer graphene powder in a mass ratio of 1:3 was used as an example: the sample tube was placed vertically with the electrodes facing each other, and the powder sample was placed in the middle; the heating power and time were 2100 watts and 15 seconds, respectively, and a spring was used to apply a 1.46 mm extension force to the top of the upper electrode. The maximum abundance (dV / dD) of the graphene micropores obtained by acid washing and drying was 0.0322 cm 3 ·g -1 nm -1 , the specific surface area is 924.62m 2 / g.

[0025] [Corrected 16.06.2025 according to Rule 91] Example 5: 0.25 g of a ball-milled mixed powder sample of sodium hydroxide and few-layer graphene powder in a mass ratio of 1:3 was used as an example: the sample tube was placed vertically with the electrodes facing each other, and the powder sample was placed in the middle; the heating power and time were 2100 watts and 15 seconds, respectively, and a spring was used to apply a 2.12 mm extension force to the top of the upper electrode. The maximum abundance (dV / dD) of the graphene micropores obtained by acid washing and drying was 0.0485 cm 3 ·g -1 nm -1 , the specific surface area is 952.85m 2 / g.

[0026] [Corrected 16.06.2025 according to Rule 91] Example 6: 0.25 g of a ball-milled mixed powder sample of sodium hydroxide and few-layer graphene powder in a mass ratio of 1:3.33 was used as an example: the sample tube was placed vertically with the electrodes facing each other, and the powder sample was placed in the middle; the heating power and time were 2100 watts and 15 seconds, respectively, and a spring was used to apply a 2.81 mm extension force to the top of the upper electrode. The maximum abundance (dV / dD) of the graphene micropores obtained by acid washing and drying was 0.0493 cm 3 ·g -1 nm -1 , the specific surface area is 948.73m 2 / g.

[0027] [Corrected 16.06.2025 according to Rule 91] Example 7: 0.25 g of a ball-milled mixed powder sample of sodium hydroxide and few-layer graphene powder in a mass ratio of 1:3.33 was used as an example: the sample tube was placed vertically with the electrodes facing each other, and the powder sample was placed in the middle; the heating power and time were 2100 watts and 15 seconds, respectively, and a spring was applied to the top of the upper electrode to apply a 2.95 mm extension force. The maximum abundance (dV / dD) of the graphene micropores obtained by acid washing and drying was 0.0483 cm 3 ·g -1 nm -1 , the specific surface area is 942.63m 2 / g.

[0028] [Corrected 16.06.2025 according to Rule 91] For example, a 0.25g sample of a ball-milled mixture of sodium hydroxide and few-layer graphene powder in a mass ratio of 1:3.33 was used: the sample tube was placed vertically, with the electrodes facing each other, and the powder sample sandwiched between them. The heating power and time were 2100 watts and 15 seconds, respectively, and a spring applied a 3.22mm extension force to the top of the upper electrode. The maximum abundance (dV / dD) of the graphene micropores obtained by acid washing was 0.0486cm 3 ·g -1 nm -1 , the specific surface area is 928.44m 2 / g.

Claims

1. A device for heating volatile powder using Joule heat, comprising a first electrode head and a second electrode head, characterized in that: The first electrode head and the second electrode head are both arranged vertically. A chamber for placing volatile powder is provided on the second electrode. The first electrode head is located above the second electrode head. The first electrode head can be pressed tightly on the volatile powder in the chamber. During the power-on process, the current flows through the volatile powder in a vertical direction and self-conducts and self-heats the volatile powder. The first electrode head can also move upward at a set time.

2. The device for heating volatile powder using Joule heat according to claim 1, characterized in that: The surface of the electrode head in contact with the volatile powder is a horizontal surface.

3. The device for heating volatile powder using Joule heat according to claim 1, wherein: The chamber is an open groove-shaped structure.

4. The device for heating volatile powder using Joule heat according to claim 3, wherein: The first electrode head can be clearance-fitted in the cavity, and the clearance is no greater than 5 mm.

5. The device for heating volatile powder using Joule heat according to claim 3, wherein: The first electrode head cannot directly contact the second electrode head. Preferably, the upper surface of the powder sample is slightly higher than the upper port of the chamber by 0.5 mm.

6. The device for heating volatile powder using Joule heat according to claim 1, wherein: The first electrode head is connected to an actuator, which is used to control the first electrode head to quickly spring upward at a set time. The actuator is also used to control the first electrode head to press down according to a set pressure.

7. The device for heating volatile powder using Joule heat according to claim 1, wherein: It also includes a temperature monitoring system, which is used to monitor and feedback the temperature of the volatile powder in the chamber in real time.

8. The device for heating volatile powder using Joule heat according to any one of claims 1 to 7, characterized in that: During the power-on process, the volatile powder is always in a compressed state.

9. A heating method using the device for heating volatile powder using Joule heat according to any one of claims 1 to 8, characterized in that the steps include: Step 1: Add volatile powder into the chamber when the first electrode head is in an open state; Step 2: Control the first electrode head to press down according to a set pressure so that the first electrode head is pressed tightly against the volatile powder; Step 3, applying power to form a conductive path among the first electrode head, the volatile powder, and the second electrode head; Step 4: monitor the temperature of the volatile powder in real time. When the temperature of the volatile powder reaches the target temperature, immediately control the power circuit to be de-energized and immediately control the first electrode head to be ejected.

10. The heating method according to claim 8, wherein: The volatile powder is acidified graphite with a particle size of 15-30 microns.

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