Abstract: In order to solve the low unit area treatment capacity, nonideal separation effect and feeding external moisture not over 7% problem existed in the large pneumatic dry separation equipment, a CFX-48A mode differential type pneumatic dry separator was researched and developed.The site application results showed tha t the differential type pneumatic dry separator could make the treatment capacity increased by 10%-30% for the unit area of the equipment, could save the energy by 5 0%-65%，the separation effect Ep value was 0. 17, reduced by 0.06 and could make the external moisture content of the feeding with suitable range from