阅读说明：本技术 一种稀土氧化物废渣回收稀土氧化物的方法 (Method for recovering rare earth oxide from rare earth oxide waste residues ) 是由 易启辉 钟书岚 刘再良 廖智文 徐剑波 于 2020-05-18 设计创作，主要内容包括：本发明公开了一种稀土氧化物废渣回收稀土氧化物的方法,通过氧化焙烧及粉碎研磨、浓硫酸溶解、草酸沉淀、沉淀焚烧以及溶液处理四个步骤完成回收稀土氧化物,焚烧炉焚烧和马弗炉灼烧的整个过程中产生废气、热气均经过旋风除尘器除尘,除尘后经过气体冷却器进一步回收余热后排出。本发明一种稀土氧化物废渣回收稀土氧化物的方法,回收处理方法简单,相较于传统的稀土氧化物回收方式,能够有效降低生产成本,提高生产效率；本发明通过浓硫酸溶解氧化物废渣,得到的反应物溶液进行稀释可以作为酸性土壤的肥料；本发明实现热循环的目的,能有效地节省能源,并且可以有效地保护了环境和利用余热。(The invention discloses a method for recovering rare earth oxide from rare earth oxide waste residue, which comprises the steps of oxidizing roasting, crushing and grinding, dissolving in concentrated sulfuric acid, precipitating oxalic acid, precipitating and incinerating, and treating solution to recover rare earth oxide. The method for recovering rare earth oxide from the rare earth oxide waste residue is simple in recovery treatment method, and compared with the traditional rare earth oxide recovery mode, the method can effectively reduce the production cost and improve the production efficiency; the invention dissolves oxide waste residue by concentrated sulfuric acid, and the obtained reactant solution is diluted to be used as fertilizer of acid soil; the invention realizes the purpose of heat circulation, can effectively save energy, and can effectively protect the environment and utilize waste heat.)

1. A method for recovering rare earth oxide from rare earth oxide waste residue is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps: oxidizing roasting, crushing and grinding: removing impurities such as water, oil and the like on the surface of the oxide waste residue, putting the cleaned oxide waste residue into an incinerator for incineration, putting the calcined waste residue into a grinder for grinding to powder;

step two: decomposing concentrated sulfuric acid: putting the crushed and ground waste residues into a reaction kettle, adding concentrated sulfuric acid for dissolving, passing through an anticorrosion screen to obtain a solution and a precipitate after dissolving, and keeping the precipitate;

step three: oxalic acid precipitation and precipitation incineration: putting the precipitate obtained in the step two into a second reaction kettle, adding an oxalic acid solution, uniformly stirring, passing through an anticorrosive screen to obtain a solution and an oxalic acid precipitate, drying the oxalic acid precipitate in a dryer, and putting the dried oxalic acid precipitate into a muffle furnace for firing to obtain rare earth oxide;

step four: and (3) putting the solution obtained in the step two into a third reaction kettle, adding carbonate into the reaction kettle, uniformly stirring, filtering through an anticorrosive screen to obtain rare earth carbonate, putting the rare earth carbonate into a dryer for drying, and then putting the dried rare earth carbonate into a muffle furnace for roasting.

2. The method for recovering rare earth oxide from rare earth oxide waste residue according to claim 1, wherein the method comprises the following steps: removing impurities such as water, oil and the like on the surface of the oxide waste residue in the first step, firstly using kerosene for coating, then coating acetic acid, and then using clean water for cleaning for 2-3 times, wherein the temperature of the clean water is 45-50 ℃, drying the cleaned waste residue in a drying furnace, the temperature of the drying furnace is 120-150 ℃, and the drying time is 1 h.

3. The method for recovering rare earth oxide from rare earth oxide waste residue according to claim 1, wherein the method comprises the following steps: in the first step, the incineration temperature of the incinerator is 900-.

4. The method for recovering rare earth oxide from rare earth oxide waste residue according to claim 1, wherein the method comprises the following steps: in the second step, the waste residue is decomposed by concentrated sulfuric acid solution with the concentration of 70-80%, and the reaction is carried out in a reaction kettle according to the ratio of concentrated sulfuric acid to waste residue of 1.8: 1, slowly pouring concentrated sulfuric acid while stirring, standing for 30 minutes after completely pouring to obtain a waste residue-concentrated sulfuric acid mixed solution, and heating the waste residue-concentrated sulfuric acid mixed solution in a box-type furnace at the temperature of 1000-1300 ℃ for 2 hours to obtain a dissolved solution, wherein the dissolving time is 2 hours.

5. The method for recovering rare earth oxide from rare earth oxide waste residue according to claim 1, wherein the method comprises the following steps: in the third step, oxalic acid solution with the concentration of 8-12% reacts with the precipitate, and the reaction is carried out in a second reaction kettle according to the ratio of the oxalic acid solution to the precipitate 3: the oxalic acid solution is slowly poured into the mixture according to the proportion of 1, the mixture is kept stand for 60 minutes after being completely poured into the mixture to obtain a precipitate-oxalic acid mixed solution, the precipitate-oxalic acid mixed solution is filtered and then is dried in a drying machine, the temperature of the drying machine is 120-150 ℃, the drying time is 1 hour, the water content of the oxalic acid precipitate before being dried is 15-20%, and the water content of the oxalic acid precipitate after being dried in a drying furnace is 5-7%.

6. The method for recovering rare earth oxide from rare earth oxide waste residue according to claim 1, wherein the method comprises the following steps: and in the third step, the oxalic acid precipitate is put into a muffle furnace for ignition, the temperature of the muffle furnace is 500-1000 ℃, the ignition time is 1h, hot air during drying of the drying furnace is provided by ignition of the muffle furnace, and the hot air after drying of the drying furnace is recycled into the muffle furnace through a heat exchanger.

7. The method for recovering rare earth oxide from rare earth oxide waste residue according to claim 1, wherein the method comprises the following steps: and in the fourth step, slowly pouring hydrochloride into the third reaction kettle according to the ratio of the solution to the carbonate of 1.5:1, stirring while pouring, standing for 1-3 hours after completely pouring to obtain rare earth carbonate slurry, filtering, putting the rare earth carbonate precipitate into a dryer for drying, wherein the temperature of the dryer is 150 ℃, the drying time is 1 hour, the dried precipitate is put into a muffle furnace for ignition, the temperature of the muffle furnace is 1000 ℃, and the ignition time is 1 hour.

8. The method for recovering rare earth oxide from rare earth oxide waste residue according to any one of claims 3, 6 or 7, characterized in that: waste gas and hot gas generated in the whole process of incineration of the incinerator and firing of the muffle furnace are dedusted by the cyclone deduster, and the dedusted waste gas is discharged after being further recovered by the gas cooler.

Technical Field

The invention relates to the technical field of rare earth oxide recovery, in particular to a method for recovering rare earth oxide from rare earth oxide waste residues.

Background

Rare earth oxide has all obtained extensive application in fields such as oil, pottery, chemical industry, metallurgy, weaving, glass, and along with the development of science and technology, rare earth oxide's demand is bigger and bigger, has a large amount of rare earth oxide in the rare earth oxide waste residue, if not handle, can cause the extremely waste of resource, but if handle inappropriately, can cause great pollution to the environment, must reduce the emission of sewage and harmful gas through some methods in the processing procedure.

However, the existing treatment method for recovering rare earth oxide from rare earth oxide waste residue often has certain limitations, the existing method usually uses an electrolysis method and a hydrochloric acid full-solution method, the electrolysis method needs more equipment, has large energy consumption and high cost, the hydrochloric acid full-solution method can generate a large amount of harmful gas during combustion, pollutes the environment, the generated waste heat cannot be recovered and reused, and the environment can be damaged when the hot gas is discharged into the atmosphere without being treated.

Disclosure of Invention

The invention mainly aims to provide a rare earth oxide recovered from rare earth oxide waste residue, which aims to solve the problems that the existing treatment method for recovering rare earth oxide from rare earth oxide waste residue needs more equipment, has large energy loss and high cost, can generate a large amount of harmful gas during combustion, pollutes the environment, can not recover and reuse the generated waste heat, can damage the environment when hot gas is discharged into the atmosphere without being treated, and the like.

In order to achieve the purpose, the invention adopts the technical scheme that: a method for recovering rare earth oxide from rare earth oxide waste residue is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps: oxidizing roasting, crushing and grinding: removing impurities such as water, oil and the like on the surface of the oxide waste residue, putting the cleaned oxide waste residue into an incinerator for incineration, putting the calcined waste residue into a grinder for grinding to powder;

step two: decomposing concentrated sulfuric acid: putting the crushed and ground waste residues into a reaction kettle, adding concentrated sulfuric acid for dissolving, passing through an anticorrosion screen to obtain a solution and a precipitate after dissolving, retaining the precipitate, and diluting the solution to be used as a raw material for preparing the acid soil fertilizer;

step three: oxalic acid precipitation and precipitation incineration: putting the precipitate obtained in the step two into a second reaction kettle, adding an oxalic acid solution, uniformly stirring, passing through an anticorrosive screen to obtain a solution and an oxalic acid precipitate, drying the oxalic acid precipitate in a dryer, and putting the dried oxalic acid precipitate into a muffle furnace for firing to obtain rare earth oxide;

step four: and (3) putting the solution obtained in the step two into a third reaction kettle, adding carbonate into the reaction kettle, uniformly stirring, filtering through an anticorrosive screen to obtain rare earth carbonate, putting the rare earth carbonate into a dryer for drying, and then putting the dried rare earth carbonate into a muffle furnace for roasting.

Further, in the first step, removing impurities such as water, oil and the like on the surface of the oxide waste residue, firstly, using kerosene to wipe, then coating with the acetic acid, then using clean water to clean for 2-3 times, wherein the temperature of the clean water is 45-50 ℃, drying the cleaned waste residue in a drying furnace, the temperature of the drying furnace is 120-150 ℃, and the drying time is 1 h.

Further, the incineration temperature of the incinerator in the first step is 900-.

Further, in the second step, the waste residue is decomposed by concentrated sulfuric acid solution with the concentration of 70-80%, and the concentrated sulfuric acid and the waste residue are added into a reaction kettle according to the ratio of 1.8: 1, slowly pouring concentrated sulfuric acid while stirring, standing for 30 minutes after completely pouring to obtain a waste residue-concentrated sulfuric acid mixed solution, and heating the waste residue-concentrated sulfuric acid mixed solution in a box-type furnace at the temperature of 1000-1300 ℃ for 2 hours to obtain a dissolved solution, wherein the dissolving time is 2 hours.

Further, oxalic acid solution with the concentration of 8-12% reacts with the precipitate in the third step, and the reaction is carried out in a second reaction kettle according to the ratio of the oxalic acid solution to the precipitate 3: the oxalic acid solution is slowly poured into the mixture according to the proportion of 1, the mixture is kept stand for 60 minutes after being completely poured into the mixture to obtain a precipitate-oxalic acid mixed solution, the precipitate-oxalic acid mixed solution is filtered and then is dried in a drying machine, the temperature of the drying machine is 120-150 ℃, the drying time is 1 hour, the water content of the oxalic acid precipitate before being dried is 15-20%, and the water content of the oxalic acid precipitate after being dried in a drying furnace is 5-7%.

Further, in the third step, the oxalic acid precipitate is put into a muffle furnace for burning, the temperature of the muffle furnace is 500-1000 ℃, the burning time is 1h, hot air during drying of the drying furnace is provided by burning of the muffle furnace, and the hot air after drying of the drying furnace is recycled into the muffle furnace through a heat exchanger.

Further, in the fourth step, hydrochloride is slowly poured into the third reaction kettle according to the ratio of the solution to the carbonate of 1.5:1, stirring is carried out while chamfering, the mixture is completely poured and then stands for 1-3 hours to obtain rare earth carbonate slurry, after filtration, the rare earth carbonate precipitate is put into a dryer for drying, the temperature of the dryer is 120-plus-material temperature 150 ℃, the drying time is 1 hour, after drying, the mixture is put into a muffle furnace for ignition, the temperature of the muffle furnace is 500-plus-material temperature 1000 ℃, and the ignition time is 1 hour

Furthermore, waste gas and hot gas generated in the whole process of incineration of the incinerator and firing of the muffle furnace are dedusted by the cyclone deduster, and the dedusted waste heat is further recovered by the gas cooler and then discharged.

The invention has the following beneficial effects:

the rare earth oxide recovery processing method is simple, can effectively reduce the production cost and improve the production efficiency compared with the traditional rare earth oxide recovery mode, and has strong market popularization value.

The invention can also recover the rare earth oxide by dissolving the oxide waste residue by concentrated sulfuric acid and processing the obtained reactant solution.

The hot air of the dryer is provided by burning of the incinerator and burning of the muffle furnace, and the hot air used by the dryer is fed back to the incinerator and the muffle furnace through the heat exchanger, so that the purpose of thermal circulation is achieved, energy can be effectively saved, and the environment can be effectively protected and waste heat can be effectively utilized by using the gas cooler and the cyclone dust collector.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.