1. scope of application

 Green production of rare earths.

2. Core technologies and processes

 In view of the bottleneck problem of rare earth mining, a magnesium salt system was used to replace the traditional ammonium sulfate leaching ionic rare earth ore to obtain a low-concentration rare earth leaching solution, and a centrifugal extraction and enrichment process was used to replace the traditional ammonium bicarbonate precipitation and enrichment process. Aiming at the bottleneck problem of rare earth separation, self-made magnesium bicarbonate solution was used instead of liquid ammonia, liquid alkali, ammonium bicarbonate or sodium carbonate for saponification, extraction and precipitation crystallization to prepare high-purity rare earth compounds. At the same time, the generated magnesium-containing wastewater and CO2 gas were recycled.

3. main technical parameters

 The rare earth leaching rate of magnesium salt system leaching ore is equivalent to that of ammonium sulfate leaching; the rare earth recovery rate of ion ore is increased by more than 8%. Magnesium bicarbonate solution is used for rare earth extraction, separation and precipitation crystallization. The rare earth extraction rate reaches 99.5%, the purity of rare earth products reaches 3N-5N, and the recycling rate of magnesium salt wastewater and CO2 gas is ≥90%.

4. comprehensive benefits

 Mine ammonia nitrogen pollution and radioactive waste residue pollution have been eliminated from the source, and the problem of ammonia nitrogen and high-salt wastewater treatment during the rare earth separation process has been solved. The comprehensive economic benefits of producing 1 ton of rare earth oxides reach 16,000 - 20,000 yuan.