Abstract: A waste processing apparatus for separating a target material from other materials lighter than the target material and dust, and for classifying the target material into one or more fractions, comprising a housing having an opening for the input of waste, a first end and a second end; a first sieve screen positioned under the opening and extending between the first and second ends; a first channel, underneath the first sieve screen, for conveying a first air stream from a first channel inlet at the first end of the housing to a first channel outlet at the second end of the housing, the first air stream serving to entrain lighter materials and dust which have passed through the first sieve screen and transporting them to the first channel outlet; a vibrator operable to urge target material that has passed through the first sieve screen towards a first target material outlet at the first end of the housing; wherein the apparatus further comprises a barrier, located between the first sieve screen and the first