Abstract: In a disk-type decker that is employed to drain suspensions and that has axially distributed suspension chambers and filtrate chambers that are separated by rotating screen disks and open into a stationary tub, the filtrate chambers are evacuated to increase the throughput of the decker and improve and accelerate drainage. The filtrate chambers are for this purpose divided by radial and axial transverse partitions into individual filtrate-chamber sections distributed along the circumference and sealed off from one another. When the screen disks and hence the filtrate-chamber sections rotate and the sections enter into flow engagement with filtrate outlets at the bottom of the decker, they are simultaneously evacuated, accelerating drainage through the disks. The results are a higher throughput, a lower material density in the filtrate, and lower specific investment costs at the same throughput or material density in the filtrate.