the present invention relates to a method and apparatus for the continuous discharge of water from suspension , especially from fibrous pulp , whereby pulp is caused to thicken without having the water to be removed through a thick uncontrollably gathered fiber mat . in accordance with the invention the suspension to be thickened is fed into a filtering chamber , the suspension is formed as a layer that is continuously being mixed for equalizing the consistency differences , the liquid is continuously removed from the suspension and the thickness of the fiber mat being formed on the filter surface is controlled by subjecting said mat to shear stresses . the above described method is realized by an apparatus , in which at least one of the co - operating surfaces , the filtering surface and its counter surface , is provided with means for non - mechanically limiting the thickness of a fiber mat on the filtering surface , whereby a uncontrolled formation of a fiber mat on the filtering surface is prevented .