A sludge thickening apparatus for dosing sludge with a cationic polyelectrolyte, allowing time for the development of a floc structure, placing the dosed sludge onto a surface through which liquid may drain freely by gravity in such a manner that the floc structure is retained, and removing the thickenened thickened sludge from said structure sludge thickening  apparatus for dosing sludge with a cationic polyelectrolyte, allowing time for the development of a floc structure, placing the dosed  sludge onto a surface through which liquid may drain freely by gravity in such a manner that the floc structure is retained, and removing the thickened sludge from said structure. sludge thickening apparatus for dosing sludge with a cationic polyelectrolyte, allowing time for the development of a floc structure, placing the dosed sludge onto a surface through which liquid may drain freely by gravity in such a manner that the floc structure is retained, and removing the thickened sludge from said structure.

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