CN215909670U

CN215909670U - Annular internal heating vacuum furnace

Info

Publication number: CN215909670U
Application number: CN202121791432.0U
Authority: CN
Inventors: 姚耀春
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-08-03
Filing date: 2021-08-03
Publication date: 2022-02-25
Anticipated expiration: 2031-08-03

Abstract

The utility model provides an annular internal heating vacuum furnace, which comprises a furnace shell, a heat insulation layer, a fireproof support and a furnace bottom, wherein the fireproof support is arranged on the furnace bottom, a heating body is wound on the fireproof support, a material box support is sleeved outside the fireproof support, a material box is arranged on the material box support, the heat insulation layer and the furnace shell are covered on the material box support and are in sealing fit with the furnace bottom, an inert gas hole is formed in the bottom of the furnace bottom, and a vacuum pipe opening and a vacuum pressure gauge are arranged at the top of the furnace shell corresponding to the heat insulation layer.

Description

Annular internal heating vacuum furnace

Technical Field

The present invention relates to vacuum furnaces, and more particularly, to an annular internal heating vacuum furnace.

Background

The lithium iron phosphate anode material in the lithium ion battery anode material has the advantages of high specific capacity, low price, no environmental pollution, good safety and thermal stability and the like, so that the lithium iron phosphate anode material becomes a promising new-generation safe and environment-friendly lithium ion power battery anode material, can be widely applied to the fields of new energy automobiles, energy storage equipment, uninterruptible power supplies, electric tools and the like, and has very wide market prospect.

Most of the current lithium iron phosphate anode materials are prepared by a high-temperature solid-phase synthesis method: mixing lithium salt, iron salt, phosphorus salt and other main materials and some additive in stoichiometric ratioThen, under the protection of inert atmosphere such as argon or nitrogen, the mixture is primarily decomposed at about 300 ℃, then the temperature is raised to 600-800 ℃, and the temperature is kept for more than 12 hours, so that LiFePO can be obtained₄And (3) a positive electrode material.

The large-scale production of lithium iron phosphate anode materials at home and abroad mostly adopts an inert atmosphere protection furnace (such as a mesh belt furnace, a push plate furnace, a rotary kiln and other devices), and the production devices need to be filled with a large amount of protective gases such as nitrogen, argon and the like all the time in the whole material production process; the material is not synthesized in a fully sealed state, the oxygen content in the furnace is not suitable to be controlled, and divalent iron ions and coated carbon are easy to oxidize; the material synthesis time is long, the temperature is high, and the energy consumption is high; waste gases such as carbon dioxide and the like generated in the material synthesis process can not be discharged in a centralized manner, and environmental pollution to a certain degree can be caused. How to prevent the oxidation of ferrous iron and ensure the consistency of products in the synthesis process of the lithium iron phosphate material is the key point of industrialization.

Disclosure of Invention

The utility model aims to provide an annular internal heating vacuum furnace, which overcomes the defects of large inert gas amount, high energy consumption, easy oxidation of ferrous ions, large loss of coated carbon content, poor batch stability, environmental pollution and the like, and can save equipment investment.

The utility model aims to realize the purpose, which comprises a furnace shell, a heat-insulating layer, a fireproof support and a furnace bottom, wherein the fireproof support is arranged on the furnace bottom, a heating body is wound on the fireproof support, a material box support is sleeved outside the fireproof support, a material box is arranged on the material box support, the heat-insulating layer and the furnace shell are covered on the material box support and are in sealed fit with the furnace bottom, an inert gas hole is formed in the bottom of the furnace bottom, and a vacuum pipe opening and a vacuum pressure gauge are arranged at the top of the furnace shell corresponding to the heat-insulating layer.

Compared with the prior art, the utility model has the following advantages and effects:

because the material support and the furnace bottom are connected into a whole, after the materials are subjected to heat preservation and sintering, the furnace shell and the heat preservation layer are lifted away, the materials can be naturally cooled by being exposed in the air, and cooling water can also be introduced into the cooling water containing cavity between the furnace shell and the heat preservation layer for cooling. Inert gas is filled from the bottom, so that the use amount of protective gas such as nitrogen, argon and the like can be greatly reduced, the production cost is reduced, and meanwhile, the material is synthesized in a fully-sealed vacuum state, so that the oxidation of ferrous ions and the loss of the content of coated carbon can be avoided; the oxygen content in the vacuum furnace is accurately controlled, stable production can be realized, and the batch stability is good. Is suitable for preparing the anode material of the ion battery.

Drawings

FIG. 1 is a schematic sectional view of an annular internally heated vacuum furnace according to the present invention;

FIG. 2 is a front schematic view of the matching relationship between the heating body and the furnace bottom of the utility model,

FIG. 3 is a schematic perspective view of FIG. 2;

FIG. 4 is a schematic perspective view of the present invention with the furnace shell, insulation layer and heating body removed;

FIG. 5 is a schematic view of the magazine of the present invention;

FIG. 6 is a schematic top view of the cartridge holder according to the utility model;

in the figure, 1-furnace shell, 2-insulating layer, 3-fire-resistant support, 4-heating body, 5-material box support, 51-material box clamping groove, 52-hoop, 6-material box, 61-concave part, 62-convex strip, 7-vacuum pipe orifice, 8-vacuum pressure gauge, 9-furnace bottom, 10-inert gas hole and 11-fixing hole.

Detailed Description

The utility model is further described with reference to the accompanying drawings, but the utility model is not limited in any way, and any alterations or substitutions based on the teaching of the utility model are within the scope of the utility model.

As shown in attached figures 1-6, the furnace comprises a furnace shell 1, a heat-insulating layer 2, a refractory support 3 and a furnace bottom 9, wherein the refractory support 3 is arranged on the furnace bottom 9, a heating body 4 is wound on the refractory support 3, a material box support 5 is sleeved outside the refractory support 3, a material box 6 is arranged on the material box support 5, the heat-insulating layer 2 and the furnace shell 1 are covered on the material box support 5 and are in sealing fit with the furnace bottom 9, an inert gas hole 10 is arranged at the bottom of the furnace bottom 9, and a vacuum pipe opening 7 and a vacuum pressure gauge 8 are arranged at the top of the furnace shell 1 corresponding to the heat-insulating layer 2.

The feed box support 5 is provided with a feed box clamping groove 51, the bottom of the feed box 6 is provided with a convex strip 62, and the feed box clamping groove 51 is matched with the convex strip 62.

The material box support 5 is provided with an anchor ear 52, and the anchor ear 52 is sleeved on the fire-resistant support 3.

The magazine 6 is provided with a recess 61, and the recess 61 is matched with the refractory support 3.

The magazine slot 51 is a dovetail slot.

And a lifting ring is arranged at the top of the furnace shell 1.

The upper part of the outer wall of the furnace shell 1 is provided with a cooling water inlet, the lower part of the outer wall of the furnace shell 1 is provided with a cooling water outlet, and a cooling water containing cavity is formed between the furnace shell 1 and the heat preservation layer 2.

The furnace shell 1, the heat preservation layer 2 and the furnace bottom 9 are connected through a fixing hole 11, and a sealing ring is arranged between the furnace shell and the furnace bottom 9 for sealing.

Working principle and working process of the utility model

When the annular internal heating vacuum furnace is used, firstly, the prepared materials are placed into the material box 6, the material box 6 is placed on the material box support 5, the convex strip 62 at the bottom of the material box 6 slides into the material box clamping groove 51 on the material box support 5 and is pushed to a certain position, when the cross part of the convex strip 62 is clamped, the material box position is shown to be in place, then the material box support 5 with the material box placed thereon is sleeved on the fireproof support 3 from top to bottom, the hoop 52 on the material box support 5 penetrates through the fireproof support 3, the fireproof support 3 is fixed on the furnace bottom 9, then the heat-insulating layer 2 and the furnace shell 1 (the heat-insulating layer and the furnace shell are of an integrated structure) cover the material box support 5 from top to bottom, and the heat-insulating layer, the furnace shell and the furnace bottom are sealed;

then, a vacuum pump is used for pumping the furnace to high vacuum and then closing the furnace, then inert gases such as nitrogen, argon and the like are injected into the furnace through an inert gas hole at the bottom of the furnace bottom to slight vacuum, and the process is repeatedly circulated until the oxygen content in the furnace is below 10 multiplied by 10 < -6 > (10 ppm); then closing the inert gas pipeline, starting the heating device to heat, extracting waste gas generated in the furnace through the vacuum pipeline in the heating process, then performing centralized pollution discharge treatment, heating to a specified temperature, roasting at a constant temperature for several hours, closing the heating device, then lifting the furnace shell and the heat insulation layer away to expose materials in the air for natural cooling, opening a cooling water inlet and a cooling water outlet on the furnace shell for water cooling, then closing the vacuum-extracting pipeline, opening the inert gas pipeline, injecting inert gas, lifting the furnace shell and the heat insulation layer away after the furnace reaches normal pressure, and taking out the materials.

While the present invention has been described in detail with reference to the embodiments, the scope of the present invention is not limited to the embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.

Claims

1. The utility model provides an annular internal heating vacuum furnace, includes stove outer covering (1), heat preservation (2), fire-resistant pillar (3), stove bottom (9), its characterized in that fire-resistant pillar set up and lie in stove bottom (9), fire-resistant pillar (3) on the winding set up heating member (4), fire-resistant pillar (3) overcoat is equipped with magazine support (5), sets up magazine (6) on magazine support (5), heat preservation (2) and stove outer covering (1) on magazine support (5) and with stove bottom (9) seal fit the bottom of stove bottom (9) be provided with inert gas hole (10) stove outer covering (1) and the corresponding top of heat preservation (2) be provided with vacuum pipe mouth (7) and vacuum pressure table (8).

2. The annular internal heating vacuum furnace as claimed in claim 1, wherein the magazine holder (5) is provided with a magazine slot (51), the bottom of the magazine (6) is provided with a raised line (62), and the magazine slot (51) is matched with the raised line (62).

3. The annular internal heating vacuum furnace as claimed in claim 1 or 2, wherein the magazine support (5) is provided with a hoop (52), and the hoop (52) is sleeved on the refractory support (3).

4. An internally heated annular furnace according to claim 1, wherein the magazine (6) is provided with recesses (61), said recesses (61) being adapted to engage with the refractory supports (3).

5. The annular internal heating vacuum furnace according to claim 2, wherein the magazine clamping groove (51) is a dovetail groove.

6. The annular internally heated vacuum furnace according to claim 1, characterized in that the furnace shell (1) is provided with a lifting ring on top.

7. The annular internal heating vacuum furnace according to claim 1, characterized in that a cooling water inlet is arranged at the upper part of the outer wall of the furnace shell (1), a cooling water outlet is arranged at the lower part of the outer wall of the furnace shell (1), and a cooling water containing cavity is formed between the furnace shell (1) and the insulating layer (2).

8. The annular internal heating vacuum furnace as claimed in claim 1, wherein the furnace shell (1) and the insulating layer (2) are connected with the furnace bottom (9) through fixing holes (11), and are sealed with the furnace bottom (9) through sealing rings.