Mechanical separation device

A rotary tool for a mechanical separator, the tool can optionally comprise: a center shaft having a longitudinal axis; a plurality of longitudinal paddles coupled to the shaft, at least one paddle of the plurality of paddles having an inner edge and aligned radially relative to the longitudinal axis, wherein the at least one paddle has an elongate extent along the longitudinal axis with opposing lateral sides along the elongate extent; and a flange having a triangular shape in a radial cross-section, the flange affixed to the inner edge of the at least one paddle and having an apex radially inward of the at least one paddle. Other examples of the application include the rotary tool having a plurality of tools and the mechanical separator having the capability of being raised or lowered to alter a residence time of slurry within the mechanical separator.