The sifter (also refered to as sieves, screens and screeners) is a separator, usually oscillating, with a number of screens. It is used to separate crumbles or granules which are too large, both in pellet and crumble manufacture, and to screen off the dusty portion (fines) of the feed for return to the pelleter for further processing. The sifter (See picture below) is a means of ensuring a good quality product with the right particle size and a low level of fines, which are wasteful to feed.