Cascading density separators for facilitating density-based classification of particulate material

A cascading density separator for facilitating density-based classification of particulate material, the cascading density separator comprising:

• a basin defining an interior channel, wherein the basin comprises a first lateral wall and a second lateral wall, wherein the second lateral wall comprises an outwardly angled deflection portion at a 45° angle relative to an axis of a spiral classifier disposed in the interior channel, wherein the basin is configured for:
• receiving a slurry of a particulate material;
• guiding the slurry along the interior channel;
• and
• deflecting via the outwardly angled deflection portion, at least a portion of the particulate material from an elevated position to a lower position within the interior channel for reintroduction;
• the spiral classifier positioned within the basin and interposed between the first lateral wall and the second lateral wall, wherein the spiral classifier is configured for:
• rotating about the axis;
• transporting a denser material from the particulate material upward within the interior channel;
• and
• displacing the particulate material toward the outwardly angled deflection portion during the rotating;
• and
• a spray nozzle mounted to the basin, wherein the spray nozzle is configured for:
• spraying water into the interior channel;
• and
• washing a lighter material from the particulate material downward for discharge while enabling the denser material to be retained and lifted by the spiral classifier.