Design of a Conduction-Cooled Open Gradient Superconducting Magnetic Separation Magnet

Magnetic separation of wastewater is required to solve the problem of water pollution caused by a large amount of wastewater discharge in urbanization and industrialization. Superconducting magnets reduce energy consumption, increase the magnetic field strength, and improve the magnetic separation effect compared with the traditional magnetic separation using permanent magnets and electromagnets. In this article, an open gradient superconducting magnetic separation magnet conduction cooled by a two-stage Gifford McMahon (GM) cryocooler was designed and developed. The open gradient superconducting magnetic separation magnet comprised four saddle-shaped coils and an optimized iron yoke. The radial magnetic flux density was 1 T at a distance of 20 mm from the surface of the coil at an operating current of 120 A, resulting in a magnetic force density of 3.5*10 ⁷ N/m ³ , with a peak field in the coil of 4.82 T. In addition, this article proposed a superconducting coil structure and winding method with an end positioning groove. The design and manufacture of the end former, as well as the magnet structure, was completed. Finally, this article designed a compact cryostat with a two-stage GM cryocooler.