Apparatus for cleaning a suspension, preferably a fiber mass suspension

An apparatus for cleaning a fiber mass suspension, said apparatus comprising:

• a receptacle for receiving the suspension to be cleaned;
• an inlet channel for feeding the suspension into the receptacle;
• an outlet channel for discharging the fiber suspension from the receptacle;
• at least one traversable partition wall for dividing the receptacle into at least an aeration space and a separate nonaeration space, said traversable partition wall being formed in such a way that the spaces are in fluid communication with each other at lower and upper portions of the traversable partition wall so that the suspension may flow from one space into the other across the traversable partition wall;
• an air feed supply for feeding air into the aeration space, said air feed supply causing air bubbles for separating impurities on the surface of the suspension and further causing a flow upwards in the aeration space, over the traversable partition wall and downwards in the nonaeration space on the other side of the traversable partition wall to thereby create a spiral flow around the partition wall between the two spaces;
• at least one nontraversable partition wall in the aeration space for dividing the aeration space into separate parts, said nontraversable partition wall extending within the receptacle such that adjacent parts of the aeration space are not in fluid communication with each other;
• and,
• at least one nontraversable partition wall in the nonaeration space for dividing the other space into separate parts, said nontraversable partition wall extending within the receptacle such that adjacent parts of the nonaeration space are not in fluid communication with each other,
• said nontraversable partition walls of said aeration space and said nonaeration space being positioned in an offset arrangement so that each part of each space is in fluid communication with another part of the other space and the fiber mass suspension is thereby caused to flow from the inlet channel to the outlet channel by moving in turns from one part in one space to another part in the other space and the fiber mass is circulated and cleaned throughout the receptacle.