A dewatering screw press has a hopper, a discharge outlet, a cylindricalscreen flexiblymounted to the hopper and rigidly connected to the discharge outlet, a screwmounted torotate beginning in the hopper and ending at the discharge outlet, the screwhaving anouter surface contacting the cylindrical screen, and at least one vibratormounted to thecylindrical screen. Dewatering efficiency is improved by vibrations that arestrong nearthe middle of the screen, while reducing or eliminating vibration near thedischarge endof the screen where pressure is highest and a breaking of the seal between thescrewand the screen due to vibration can reduce dewatering of sludge near thedischarge endof the screen.
