Apparatus for dewatering sludge comprising a primary dewatering section in which the sludge is supported on a filter means sloped downwardly towards the center, and a secondary dewatering section which follows the primary dewatering section and through which the sludge is carried on a non-filtering support which is sloped downwardly towards the side, and means for applying pressure onto the top side of the sludge layer during passage through the primary and secondary dewatering sections.

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