The device (1) has a rectilinear pipe (100) for circulating particles suspension (200), where the pipe includes sufficient length for development of a suspension layer in solid phase. Abrupt enlargement (111) of the pipe disturbs flow of suspension in the pipe and causes formation of recirculation vortex locally increasing thickness of a recirculation zone (210). A secondary pipe (121) is placed at the level of a region of a device formed with center (211), a periphery (213) and an outer zone (220) where the suspension is rich in liquid phase due to the recirculation vortex. An independent claim is also included for a method for extracting a suspension from a liquid.
