CT series of dry type, permanent magnetic roller separator is a kind of midfield magnetic device and it is mainly composed of a sorting roller, magnetic system, driving device and stander. The sorting roller is rolled by stainless steel plate. Magnetic system adopts multi-poles and a big angle design, in which (Neodymium iron boron) NdFeB is as magnetic source to keep it high magnetic field intensity and a big gradient. The driving device adopts electromagnetic control motor suitable for different speed requirements of the sorting roller.