1. Equipment for separating liquid from solid material suspended therein such as sewage and the like, comprising: an endless dewatering belt formed as a single layer and having a flat receiving surface perforated with a plurality of transverse slits; a head drum located within said dewatering belt for driving it to define an upstream and a downstream direction; at least one station for loading onto said dewatering belt the liquid containing the suspended material; at least one pressing stage defined by an endless pressing belt arranged to bear against said dewatering belt downstream of said at least one loading station for compressing the material disposed thereon, said pressing belt being substantially impervious to the liquid, imperforate, and smooth-surfaced; a plurality of rollers located within said pressing belt and adapted to permit said pressing belt to run thereover; a corresponding plurality of biassing means each connected to one of said rollers located within said pressing belt; a plurality of support rollers located within said dewatering belt, each of said support rollers being arranged in cooperating opposed relation to a corresponding roller located within said pressing belt thereby establishing points of maximum pressure therebetween exerted on said belts by said biassing means through said rollers; each of said support rollers being substantially the same diameter as its corresponding pressure roller and having its axis of rotation vertically aligned with the respective axis of rotation thereof; and circumferential groove means formed in said support rollers for permitting free flow of liquid through said dewatering belt onto said grooved support rollers at said points of maximum pressure.