Method of improving rare earth grade of hybrid rare earth ores

Abstract

The invention relates to a method of improving the rare earth grade of hybrid rare earth ores. The method is characterized by comprising the following steps: grinding the hybrid rare earth ores firstly until granules with the granularity being 200 meshes account for 85 percent or more, and then carrying out size mixing and flotation separation, wherein flotation separation is composed of roughing, scavenging and concentrating, the flotation separation temperature is larger than 80 DEG C, the activity of a collector is strengthened by raising the flotation separation temperature, and thus the dosage of the collector is lowered, and the rare earth recovery rate is also ensured; with adoption of a flotation flow combined by closed cycle and opened flow, middlings produced during flotation separation returns last flotation separation after being thickened through washing, reagent removal and desliming or directly returns last flotation separation sequentially, and various products including rare earth ore concentrates with higher grade, one or more kinds of middle-grade rare earth ore concentrates and low-grade rare earth ore tailings can be simultaneously obtained, or two kinds of products including higher-grade rare earth ore concentrates and low-grade rare earth ore tailings are obtained only through flotation separation; and the adopted reagents are as follows: sodium silicate is taken as an inhibitor, the collector is a hydroxamic acid collector, and pine camphor oil is taken as a foaming agent. The method is wide in application range, multiple in product varieties, little in reagent dosage and high in rare earth recovery rate, can be directly applied to large rare earth concentration plants and realizes diversification of hybrid rare earth ore concentrate products.

Description

technical field [0001] The invention relates to a method for increasing the grade of rare earth in a mixed type rare earth ore, which belongs to the field of ore dressing. Background technique [0002] Mixed rare earth ores refer to rare earth ores composed of bastnaesite and monazite in a certain proportion, mainly referring to Baotou Baiyan Obo mixed light rare earth ores. The rare earth reserves of Baotou Baiyun Obo Mine rank first in the world, accounting for 83% of my country's total. It is one of the earliest rare earth deposits discovered and developed in my country. , the rare earth utilization rate is less than 10%. Most of the rare earth resources are discharged to Baotou Iron and Steel tailings dam stockpiling along with iron mining. is still increasing. [0003] At present, the way to recover rare earth resources is mainly to recover from the tailings of Baotou Steel’s iron beneficiation. A small amount of rare earth ore processing plants directly recover from Ba...

AI Technical Summary

Problems solved by technology

The smelting process determines the types of rare earth concentrate products. At present, the rare earth concentrator only produces two kinds of rare earth concentrate products with a grade of about 50% and a grade of 55-60%. The rare earth concentrate with a grade of about 50% is used to extract rare earth by concentrated sulfuric acid roasting The rare earth concentrate with a grade of 55-60% is used to extract rare earths by caustic soda decomposition. The two mainstream processes have certain three-waste pollution problems that cannot be solved. The production method of the rare earth concentrator is to use the tailings after iron separation in Baotou Steel as raw material , the raw material rare earth grade is 8-10%, the particle size is -200 mesh, and the particle size is 80-85%. The open-circuit process is used to produce 50% rare earth concentrate, the tailing rare earth grade is about 2-5%, and the rare earth recovery rate is about 60%. When the particle size of the raw material is finer or the flotation conditions are better, the rare earth concentrate with a product grade of 55-60% will be produced, but the recovery rate of rare earth will decrease, so the rare earth concentrator does not have a comprehensive flotation process to control the concentrate. The grade, type, and recovery rate of ore are only formulated according to the actual flotation conditions in production, which limits the development of rare earth beneficiation.

[0004] In order to solve the single type of concentrate in the rare earth industry and the pollution of three wastes in smelting, the new process of acid leaching, alkali solution, separation and smelting of rare earth concentrates with a grade of more than 65% developed by the team of Professor Li Mei of Inner Mongolia University of Science and Technology has solved the three wastes pollution of rare earth smelting. , the new process has built a production demonstration line of 65% rare earth concentrate, and produced more than 2,000 tons of 65% rare earth concentrate. Combining production lines for large-scale production, rare earth concentrators still only produce two kinds of rare earth concentrate products with a grade of about 50% and a grade of 55-60% according to the old process, which limits the development of rare earth beneficiation and smelting

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