In December 2019, a pilot plant for low-temperature acid roasting of rare earth concentrate using an externally heated rotary kiln that developed, designed, and manufactured by SNE has been successfully commissioned. The system operated continuously for over 72 hours, with all performance metrics meeting design requirements. Process parameters remained stable, and product indicators were qualified, earning unanimous approval from the owner.

This pilot plant is a collaborative effort between SNE and Northern Rare Earth Group, organized by the Northern Rare Earth Technology Center. SNE was responsible for developing, designing, manufacturing, and installation of the facility. The project site is located at the No. 1 Smelting Plant of Northern Rare Earth (Huamei).

The pilot plant was designed based on the characteristics of the sulfuric acid method for rare earth acid roasting, fully leveraging the advantages of the externally heated rotary kiln. It incorporates a structure to prevent material buildup on the walls, addressing issues such as high sulfuric acid consumption, corrosion, ring formation, poor furnace sealing, large exhaust gas volumes, high dust content, and the inability to recycle materials during the rare earth acidification process.

The successful commissioning of this low-temperature acid roasting facility for rare earth concentrate in an externally heated rotary kiln indicates that the process route for acid roasting using such kilns is both reasonable and feasible. This represents a new breakthrough in the sulfuric acid method for rare earth acidification and lays a solid foundation for upgrading the refinery process equipment and core facilities used for rare earth refinery plant.