Abstract: An apparatus for processing a solid-liquid material comprises a housing formed with a series of interconnected chambers defined by chamber walls with at least two drums mounted in series within the chambers. Each chamber receives one of the at least two drums for rotatable movement therein. Each chamber and the associated drum are dimensioned to define a region therebetween to retain the solid-liquid material. The regions of adjacent chambers communicate with each other to define a continuous passage from drum to drum through the apparatus. An inlet in the housing admits the solid-liquid material to the passage, and an outlet permits extraction of a processed solid-liquid material from the passage. Each drum rotates in a direction opposite to the adjacent drum to advance the solid-liquid material through the passage from drum to adjacent drum in a sinuous path such that the curvature of the solid-liquid material changes when passing from drum to adjacent drum.