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.