US Patent 7105085 Device for biological fluid treatment

In a device for biological fluid treatment, fluid is led along surfaces coated with microorganisms, which form parts of disks drivable about a rotation axis. The surfaces are formed by recesses lying in the disks and the disks are arranged to one another such that the leading of the fluid is effected through the recesses, and a recess of one disk is delimited in a channel-forming manner by the adjacent other disk movable relative to this.