A vertical cylindrical dewatering apparatus for dewatering fibrous slurries, slurry of manure and water, or other similar slurries. The apparatus includes a housing that includes a defined chamber having an enclosed top end with a slurry injector into the chamber, a centrally disposed first filtering element that includes first and second flightings, and a second vertical cylindrical filtering element including a support grid. The first and second filtering elements define the chamber. The slurry in-flow port at the top of the apparatus directs the slurry spiraling down between the flightings. The particles start building up at the bottom of the chamber as the water is filtered out from the housing through filtrate drains. Compressed air supplied through a rotating seal down through the centrally disposed filtering element moves through the filter, and through the particles forcing the water from between the particles out through the outer filter element. After the moisture is removed from the particles, a hinge door is opened and a drive motor turns the first filter and flightings for particle removal. An alignment ring is attached to outer edges of the lower end of said flights in order to maintain a clearance of at least ¼ inch between the outer edges and the second filter element.