The invention discloses a
processing method of fine bastnaesite. The
processing method comprises the following steps: (1) carrying out ball-milling treatment on fine bastnaesite, so as to obtain fine bastnaesite particles; (2) mixing the fine bastnaesite particles with concentrated
sulfuric acid, and curing, so as to obtain cured ores; (3)
roasting the cured ores, so as to obtain roasted ores; (4) carrying out
slurry mixing, water leaching and
filtration on the roasted ores, so as to obtain
leachate and leached
slag; (5) extracting the
leachate, so as to obtain
rare earth and
thorium-containing extraction liquid; (6) carrying out back extraction on the
thorium-containing extraction liquid, so as to obtain
thorium nitrate. By virtue of the
processing method, Sichuan fine bastnaesite can be effectively processed, furthermore, the flow is simple, the REO
leaching rate is high, the
energy consumption is low, the consumption of auxiliary materials is low, meanwhile, the content of radioactive thorium is greatly decreased into a standard range,
fluorine and radioactive thorium are not emitted in the whole process, the leached
slag can be directly emitted after being washed, the environment is protected, furthermore,
rare earth can be effectively separated, and
fluorine and thorium resources can be comprehensively utilized, so that the processing method is a novel clean production process for metallurgical treatment of fine bastnaesite.