CN-121988467-A - Cascaded cyclone separator for plasma graphitization system

Abstract

The invention discloses a cascading cyclone separator for a plasma graphitization system, which relates to the technical field of high-temperature gas-solid separation equipment, in particular to a cascading cyclone separator for a plasma graphitization system. The first separator separates graphite powder of 5 μm or more, the second separator separates graphite powder of 1-5 μm, the water cooling jacket is communicated with circulating water, the water temperature at the outlet is 40 ℃ or less, a collecting tank is arranged below the powder outlet, a cooling water channel of a cascade pipeline and a water channel of the water cooling jacket can be connected in parallel/in series, the separator is made of high-temperature resistant stainless steel, and the polishing roughness of the inner wall is 0.8 μm or less. The outlet of the system gas inlet 473K is less than or equal to 300K after separation and cooling, the maximum air pressure drop is 98.14-154.73Pa, and the critical separation particle size is 0.99-48.35 mu m.

Inventors

• ZHANG JIAQING
• WANG FUDONG
• YAO MIN

Assignees

• 江苏中丹科源新材料有限公司

Dates

Publication Date

20260508

Application Date

20260123

Claims (10)

1. 1. A cascading cyclone for a plasma graphitization system, comprising: the gas inlet of the first cyclone separator (1) is communicated with the outlet of the main reactor of the plasma graphitization system through a connecting pipeline; The gas inlet of the second cyclone separator (2) is communicated with the gas outlet of the first cyclone separator (1) through a cascade pipeline; the wall surfaces of the first cyclone separator (1) and the second cyclone separator (2) are respectively provided with a water cooling jacket (3) for reducing the internal temperature of the separators; the cascade pipe is composed of double-layer sleeves, wherein the outer layer is a cooling water channel (4), and the inner layer is an air flow channel (5).
2. 2. A cascade cyclone for a plasma graphitization system according to claim 1, wherein: The diameter of the straight section of the first cyclone separator (1) is 0.2-0.3m, the diameter of an inlet circular tube is 0.05-0.07m, the diameter of a gas outlet is 0.1-0.13m, the diameter of a powder outlet is 0.06-0.08m, the overall height is 0.5-1.2m, and the depth of an exhaust pipe is 0.025-0.042m; The diameter of the straight section of the second cyclone separator (2) is 0.1-0.2m, the diameter of the circular inlet pipe is 0.04-0.06m, the diameter of the gas outlet pipe is 0.05-0.08m, the diameter of the powder outlet pipe is 0.02-0.04m, the overall height is 0.3-0.7m, and the depth of the exhaust pipe is 0.015-0.022m.
3. 3. The cascade cyclone separator for a plasma graphitization system as claimed in claim 1, wherein the first cyclone separator (1) is used for separating graphite powder with a particle size of 5 μm or more, and the second cyclone separator (2) is used for separating graphite powder with a particle size of 1-5 μm.
4. 4. The cascading cyclone separator for the plasma graphitization system according to claim 1, wherein the cooling medium of the water cooling jacket (3) is circulating water, the inlet water temperature is normal temperature, and the outlet water temperature is not more than 40 ℃.
5. 5. The cascading cyclone separator for the plasma graphitization system according to claim 1, wherein the collecting tanks (6) are arranged below the powder outlets of the first cyclone separator (1) and the second cyclone separator (2) and are used for storing separated graphite powder.
6. 6. A cascade cyclone separator for a plasma graphitization system according to claim 1, characterized in that the cooling water channel (4) of the cascade line is connected in parallel or in series with the cooling water channel of the water cooling jacket (3).
7. 7. A cascade cyclone for a plasma graphitization system according to claim 1, characterized in that the air inlets of the first cyclone (1) and the second cyclone (2) are tangential inlets and the air flow swirls along the wall surface.
8. 8. The cascading cyclone separator for a plasma graphitization system as set forth in claim 1, wherein the gas inlet temperature of the plasma graphitization system is 473K, and the outlet gas temperature is reduced to below 300K after two-stage separation and cooling.
9. 9. The cascading cyclone separator for a plasma graphitization system according to claim 1, wherein the pressure drop of the separator under the working condition of maximum air quantity is 98.14-154.73Pa, and the critical separation particle size is 0.99-48.35 μm.
10. 10. The cascading cyclone separator for a plasma graphitization system according to any one of claims 1 to 9, wherein the separator is made of high temperature resistant stainless steel, and the inner wall surface is polished to have a roughness of 0.8 μm or less.

Description

Cascaded cyclone separator for plasma graphitization system Technical Field The invention relates to the technical field of high-temperature gas-solid separation equipment, in particular to a cascade cyclone separator for a plasma graphitization system. Background The core of the plasma graphitization technology is that the extremely high temperature (usually in the range of thousands of degrees centigrade) of the plasma is utilized to make the carbon material undergo the structural transformation to obtain the graphite powder with high crystallinity. During this process, the main reactor outlet will produce a gas stream containing high temperature graphite particles, which are widely distributed, varying from submicron to tens of microns, and which are themselves at a high temperature (up to 473K or even higher). In order to recycle graphite powder and reduce the temperature of the subsequent exhaust gas, the high-temperature dust-containing gas must be effectively separated and cooled, which is a key link for ensuring continuous and stable operation of the system, improving the product yield and meeting the environmental protection requirement. Currently, for separation of high temperature dust-containing gas, common methods include filtration, electrostatic precipitation, cyclone separation, and the like. Although the filtering method can realize high-efficiency trapping of fine particles, the filtering material is easy to age and block under the high-temperature condition, frequent in replacement, high in operation cost and insufficient in reliability under the high-temperature impact of plasma graphitization, the electrostatic precipitation method has a certain limit on the gas temperature, the high temperature can influence the electrode insulativity and discharge stability, the equipment is complex, the energy consumption is high, and the maintenance difficulty is high. In contrast, the cyclone separator has simple structure, better high temperature resistance, no moving parts and relatively low pressure loss, and is suitable for being used as a primary or intermediate stage means of high-temperature gas-solid separation. However, the traditional cyclone separator has obvious limitations in the process of treating dust with large grain size span and high-temperature working conditions, namely, the single separator is difficult to realize high-efficiency grading trapping of coarse grains and fine grains at the same time, so that part of fine grains escape or excessive abrasion of coarse grains is caused inside, the high-temperature airflow directly enters the separator to cause excessive wall heat load, local overheating and even material failure, the separation efficiency and the equipment service life are influenced, and the traditional cyclone separator is limited in cooling measures, so that the temperature of the gas is difficult to be reduced to the level required by subsequent working procedures or emission only by natural heat dissipation, and the downstream equipment is easy to be damaged by heat or waste of heat energy. In the plasma graphitization system, since graphite powder has higher economic value, the trapping rate must be improved to the maximum extent, especially, fine particles with particle size smaller than 5 μm have large specific surface area and high reactivity, and if the graphite powder is directly discharged along with waste gas, not only the product is lost, but also the environment is possibly polluted. In the prior art, a multi-cyclone series connection mode is adopted to widen the separation particle size range, but most of interstage connecting pipelines are not specially cooled, high-temperature air flow still generates thermal shock to the pipelines and the lower separator in the conveying process, and in addition, a conventional single-stage or multi-stage cyclone system lacks systematic optimization in the aspects of size matching, pressure drop control and temperature gradient management, and the problems of overload of a front stage, reduction of efficiency of a rear stage, overlarge overall pressure drop and the like are easy to occur. For example, in some designs, the diameter of the first-stage separator is too large, which results in lower separation efficiency of fine particles, while the diameter of the second-stage separator is too small and is easily blocked by coarse particles, and if the interstage pipeline is of a single-layer structure, the cooling effect is poor, and a heat exchanger needs to be additionally arranged, so that the complexity and the occupied space of the system are increased. Aiming at the problems, it is necessary to develop a high-temperature gas-solid separation device special for a plasma graphitization system, which can realize high-efficiency grading trapping of coarse and fine graphite powder under the high-temperature condition, and simultaneously effectively control the temperature of a separator and a connecting pipeline thr