Abstract: A rotary drum filter arrangement in which an endless flexible filter belt is trained around at least 270.degree. of the vacuum drum and leaves the vacuum drum for application of a slurry and formation of a cake remote from the drum. In one form of the invention the slurry is applied to a substantially horizontal portion of the belt prior to entry onto the vacuum drum so gravity aids in initial dewatering. In another form of the invention the cake is formed by an auxiliary vacuum drum prior to entry onto the main vacuum drum. By utilizing at least 270.degree. of the vacuum drum after formation of the cake, the invention provides a drier cake, easier adaptation of auxiliary washing and drying equipment and/or permits the use of a smaller vacuum drum.