for separating the foreign matter from the fibers and thus foreign matter 12 corresponds generally to plant parts and other contaminants while the fibers 13 generally correspond to cotton flax polyester or the like the apparatus 10 includes a housing 20 which preferably includes a primary separation zone or a first separator in first housing 23 and a second separation zone in second housing 24 an inlet chute 27 connects to housing 20 and communicates with first separator 23 to provide a path for introducing mixture 11 into first housing 23 preferably inlet chute 27 is a chute for feeding a mixture into the primary separation zone first housing 23 further includes an outlet 28 for discharging partially treated fiber therefrom the first separator includes a series of first separator cylinders 30 that extend through and that are rotatably supported by first housing 23 while being rotatably driven by one or more motors not shown preferably variable speed motors each cylinder 30 has a plurality of projections 31 protruding outwardly therefrom for contacting and temporarily engaging mixture 11 to separate fibers 13 from foreign matter 12 and to produce an intermediate mixture of residual fibers and foreign matter 12 the projections are also adapted to centrifugally release the fibers therefrom as the cylinder rotates without assistance from a doffing brush as used herein u201c centrifugally releasable fiber engaging projections.