Since the solid particles in the wastewater are kept early in the channel, that provides advantages in terms of operation and reduces waste load for following steps of the system. All wet parts are made of stainless steel. Due to compact design, both waste elevation and squeezing of screenings is provided at the same machine. Wastes are automatically transferred to the waste container by auger. The screenings caught by micron sieve is small as 200-micron size.