Double-acid leaching method for fluorine-containing rare earth ore

The fluorine-containing rare earth ore double-acid leaching method comprises the steps that fluorine-containing rare earth ore is subjected to oxidizing roasting, reduction leaching and solid-liquid separation, and first slag is obtained; carrying out double-acid leaching reaction on the first slag material, and carrying out solid-liquid separation to obtain a second slag material and a second material liquid; filtering and washing the second slag material, and carrying out solid-liquid separation to obtain a third slag material and a third material liquid; the third slag material is subjected to heating dissolution and heat preservation sedimentation, and supernate is obtained; obtaining a KBF4 product from the supernate; performing double salt precipitation on the second feed liquid, and performing solid-liquid separation to obtain fourth slag and fourth feed liquid; treating the fourth slag material to obtain rare earth chloride feed liquid and a precipitator sodium sulfate; evaporating and concentrating t