CN205443473U - Electrolysis tombarthite smoke and dust gas clean system - Google Patents

Abstract

An electrolytic rare earth flue gas purification system, comprising an induced draft fan connected to the gas collection hood pipe of the electrolytic furnace, the outlet of the induced draft fan is connected to a cyclone dust collector, the gas outlet of the cyclone dust collector is connected to a water mist dust removal tower, and the water mist dust removal tower is connected to the outlet of the induced draft fan The gas outlet of the mist dedusting tower is connected to the bottom inlet of the chemical spray purification tower, and the liquid outlet of the chemical spray purification tower is connected to the bottom inlet of the chemical spray purification tower through a liquid circulation loop; the top of the chemical spray purification tower is provided with a gas Water separation chamber; the electrolytic rare earth flue gas purification system also includes a dry recovery pool connected to the solid outlet of the cyclone dust collector, and a wet recovery pool connected to the solid outlet of the water mist dedusting tower. The utility model uses three-stage purification methods of cyclone dust removal, water film dust removal and chemical reaction removal of fluoride and fluoride to comprehensively recover the rare earth floating in the smoke and dust, improve the recovery rate of the rare earth process, and at the same time have a good purification effect on the tail gas, and can make the generated Exhaust emissions meet standards.

Description

An electrolysis rare earth flue gas purification system

technical field

The utility model belongs to the field of machinery, and relates to a rare earth electrolysis device, in particular to an electrolysis rare earth smoke gas purification system.

Background technique

Rare earths are known as industrial vitamins. Now it has become an extremely important strategic resource. Rare earth element oxides refer to oxides of 15 lanthanide elements with atomic numbers from 57 to 71 in the periodic table of elements, and oxides of scandium (Sc) and yttrium (Y), which are chemically similar to lanthanide elements, a total of 17 elements . Rare earth elements have been widely used in petroleum, chemical industry, metallurgy, textile, ceramics, glass, permanent magnet materials and other fields. With the advancement of science and technology and continuous breakthroughs in application technology, the value of rare earth oxides will increase.

Industrial mass production of rare earth metals generally uses molten salt electrolysis. The process uses rare earth fluoride molten salt system as electrolyte, graphite as electrolytic cell and anode material, and tungsten rod as cathode. In the molten rare earth fluoride (REF ₃ , LiF) system, the rare earth oxide (REO) is added to dissolve, and the rare earth fluoride dissociates into rare earth ions (RE ³⁺ ) and (F ^- ), and the rare earth oxide (REO) dissociates into Rare earth ions (RE ³⁺ ) and oxygen ions (O ^2- ). Under the action of an electric field, the positively charged rare earth ions move to the cathode and gain electrons at the cathode to precipitate rare earth metals (RE); the negatively charged F ^- and O ^2- oxygen ions move to the anode and lose electrons at the anode to generate F ₂ And O ₂ , O ₂ reacts with graphite anode (C) at about 1000°C to generate CO ₂ .

Utility model content

In order to overcome the technical defect of air pollution caused by the discharge of harmful gas fluorine gas produced in the existing process of rare earth electrolysis production, the utility model discloses an electrolysis rare earth fume gas purification system.

The utility model relates to an electrolytic rare earth flue gas purification system, which includes an induced draft fan connected to the gas collecting hood pipeline of the electrolytic furnace, the outlet of the induced draft fan is connected with a cyclone dust collector, and the gas outlet of the cyclone dust collector is connected with a water mist dust removal tower The inlet is connected, the gas outlet of the water mist dedusting tower is connected to the bottom inlet of the chemical spray purification tower, and the liquid outlet of the chemical spray purification tower is connected to the bottom inlet of the chemical spray purification tower through a liquid circulation loop; the chemical spray There is a gas-water separation chamber at the top of the purification tower;

The liquid circulation loop includes a sedimentation tank connected to the liquid outlet of the chemical spray purification tower, a filter device connected to the solid outlet of the sedimentation tank, and an adjustment tank connected to the liquid outlet of the sedimentation tank, and the outlet of the adjustment tank is connected through a clarification tank The bottom inlet of the chemical spray purification tower; the liquid outlet of the filter device is connected to the deployment pool;

The electrolytic rare earth flue gas purification system also includes a dry recovery tank connected to the solid outlet of the cyclone dust collector, and a wet recovery tank connected to the solid outlet of the water mist dedusting tower, the dry recovery tank outlet, the wet recovery tank solid outlet and The feed port of the electrolytic furnace is connected, and the liquid outlet of the wet recovery pool is connected with the preparation pool.

Preferably, the liquid outlet of the wet recovery pool is connected to the adjustment pool through a clear water pool.

Preferably, it also includes a solid drying tank connected to the solid outlet of the filtering device.

Using the electrolysis rare earth smoke gas purification system described in the utility model, compared with the prior art, the three-stage purification method of cyclone dust removal, water film dust removal, chemical reaction and fluorine and fluoride in the tail gas is used to comprehensively recover the rare earth floating in the smoke , improve the recovery rate of the rare earth process, and at the same time remove the fluorine in the flue gas by water mist spraying, the purification effect is good, and the exhaust gas produced can be discharged up to the standard.

Description of drawings

Fig. 1 is a schematic diagram of connection of various parts of a specific embodiment of the electrolysis rare earth smoke gas purification system described in the utility model;

The names of reference signs in the figure are: 1-gas collecting hood, 2-electrolytic furnace, 3-solid drying pool, 4-induced fan, 5-cyclone dust collector, 6-water mist dust removal tower, 7-chemical spray purification Tower, 8-gas-water separation chamber, 9-sedimentation tank, 10-filtration device, 11-adjustment tank, 12-clarification tank, 13-dry recovery tank, 14-wet recovery tank, 15-clear water tank.

detailed description

Below in conjunction with accompanying drawing, the specific embodiment of the utility model is described in further detail.

As shown in Figure 1, the electrolytic rare earth smoke gas purification system described in the utility model includes an induced draft fan 4 connected to the gas collecting cover 1 of the electrolytic furnace, the outlet of the induced draft fan is connected with a cyclone dust collector 5, and the cyclone dust collector 5 The gas outlet is connected to the water mist dedusting tower 6, the gas outlet of the water mist dedusting tower 6 is connected to the bottom inlet of the medicament spray purification tower 7, and the liquid outlet of the medicament spray purification tower 7 is connected to the medicament spray through a liquid circulation loop. There is an inlet at the bottom of the shower purification tower; a gas-water separation chamber 8 is provided at the top of the chemical spray purification tower.

The liquid circulation loop includes a sedimentation tank 9 connected to the liquid outlet of the chemical spray purification tower, a filter device 10 connected to the solid outlet of the sedimentation tank, and a blending tank 11 connected to the liquid outlet of the sedimentation tank, and the outlet of the blending tank 11 passes through The clarification tank 12 is connected to the bottom inlet of the chemical spray purification tower 7; the liquid outlet of the filter device 10 is connected to the blending tank 11;

The electrolytic rare earth flue gas purification system also includes a dry recovery tank 13 connected to the solid outlet of the cyclone dust collector 5, and a wet recovery tank 14 connected to the solid outlet of the water mist dedusting tower 6, the dry recovery tank outlet, wet recovery The solid outlet of the pool is connected to the feed port of the electrolytic furnace 2, and the liquid outlet of the wet recovery pool is connected to the blending pool 11.

The utility model is applied in the rare earth electrolytic smelting process. The gas collecting hood is arranged above the furnace mouth of the electrolytic furnace 2. After the induced draft fan 4 generates negative pressure, the rare earth dust under the gas collecting hood 1 is sucked into the cyclone dust collector 5, and the cyclone dust collector removes dust. The mechanism is to make the dust-laden air flow rotate, and the dust particles are separated from the air flow by centrifugal force and collected on the wall of the container, and then the dust particles fall into the ash hopper by gravity. The cyclone dust collector discharges the larger solid particles in the airflow to the dry recovery tank at the bottom. After the airflow passes through the cyclone dust collector, it continues to enter the water mist dedusting tower 6, which sprays water mist and continues to absorb the volume in the airflow. Smaller solid particles, the water that has absorbed the solid particles is collected to the wet recovery tank under the action of gravity, and the remaining air flow continues to enter the chemical spray purification tower for chemical absorption, where alkaline solutions such as lime can be sprayed Water defluorides the gas flow to remove acid ions such as fluoride ions that may be produced during the rare earth smelting process.

After precipitation in the wet recovery tank, the solid matter settled at the bottom and the solid particles collected in the dry recovery tank can be directly sent back to the electrolytic furnace for secondary smelting. The gas-water separation chamber 8 installed on the top of the chemical spray tower purification tower is equipped with a gas-water separator. After separating the gas and water, the non-polluting gas is discharged from the top, and the water falls to the bottom of the chemical spray tower, where it is collected by the liquid circulation loop. .

The water discharged from the bottom of the chemical spray tower first enters the sedimentation tank 9, and after a proper period of precipitation in the sedimentation tank, the sediment at the bottom enters the filter device 10, and at the same time, the clear water in the upper layer of the sedimentation tank 9 directly enters the deployment tank 11, and the filter device filters the solids , the remaining clear water enters the deployment tank 11, and the pH value of the water in the deployment tank can be reduced by adding alkaline substances through chemical reactions in the deployment tank, and the deployment tank can also be connected with the sedimentation tank and the wet recovery tank 14 liquid outlets to collect the relatively clear water discharged by the two liquid water, and further remove impurities through the clear water pool 12. The impurities can be removed by means of precipitation, flocculation, etc. to obtain clear recycled water, and sent to the chemical spray tower for recycling. A clear water pool 15 can be connected between the wet recovery pool 14 and the deployment pool 11. After the wet recovery pool has settled for an appropriate time, the clear water enters the clear water pool 15 for storage, and the sediment is directly sent back to the electrolytic furnace.

Compared with the prior art, the electrolysis rare earth smoke gas purification system described in the utility model adopts the three-stage purification method of cyclone dust removal, water film dust removal, and chemical reaction fluorine removal compound to comprehensively recover the rare earth floating in the smoke and improve the rare earth The process recovery rate is high, and at the same time, the fluorine in the flue gas is removed by water mist spraying, the purification effect is good, and the generated tail gas can be discharged up to the standard.

The foregoing are various preferred embodiments of the present utility model. If the preferred implementations in each preferred embodiment are not obviously self-contradictory or based on a certain preferred implementation, each preferred implementation can be arbitrarily superimposed and combined. The specific parameters in the described embodiments and the embodiments are only for clearly expressing the utility model verification process of the utility model person, and are not used to limit the patent protection scope of the utility model, and the patent protection scope of the utility model is still defined by its claims. As the standard, all equivalent structural changes made by using the description and drawings of the utility model should be included in the protection scope of the utility model in the same way.

Claims (3)

1. An electrolytic rare earth flue gas purification system is characterized in that, comprising an induced draft fan connected to the electrolytic furnace gas collecting hood pipeline, the outlet of the induced draft fan is connected with the cyclone dust collector, and the gas outlet of the cyclone dust collector is connected with the water mist dust removal The tower inlet is connected, the gas outlet of the water mist dedusting tower is connected with the bottom inlet of the chemical spray purification tower, and the liquid outlet of the chemical spray purification tower is connected to the bottom inlet of the chemical spray purification tower through a liquid circulation loop; the chemical spray There is a gas-water separation chamber at the top of the leaching purification tower; The liquid circulation loop includes a sedimentation tank connected to the liquid outlet of the chemical spray purification tower, a filter device connected to the solid outlet of the sedimentation tank, and an adjustment tank connected to the liquid outlet of the sedimentation tank, and the outlet of the adjustment tank is connected through a clarification tank The bottom inlet of the chemical spray purification tower; the liquid outlet of the filter device is connected to the deployment pool; The electrolytic rare earth flue gas purification system also includes a dry recovery tank connected to the solid outlet of the cyclone dust collector, and a wet recovery tank connected to the solid outlet of the water mist dedusting tower, the dry recovery tank outlet, the wet recovery tank solid outlet and The feed port of the electrolytic furnace is connected, and the liquid outlet of the wet recovery pool is connected with the preparation pool. 2. The electrolytic rare earth flue gas purification system according to claim 1, characterized in that the liquid outlet of the wet recovery pool is connected to the preparation pool through a clear water pool. 3. The electrolytic rare earth flue gas purification system as claimed in claim 1, further comprising a solid drying pool connected to the solid outlet of the filter device.