The invention relates to an apparatus and a process for taking up particles, in particular particles of oil, algae or dirt, from a water surface (2). A hull structure (1) is moved over the water surface (2). In this case, a flow (6) of water laden with particles is produced in the region of a bottom surface (7) of the hull structure (1). The flow (6) is broken away or interrupted along a vortexing edge (13) in the region of the bottom hull-structure surface (7), with the result that a vortex flow (14) is produced for at least some of the particle-laden water. The vortex flow (14) passes into a vortex flow space (15). With the aid of localizing means, the vortex flow (14) is localized in a separation section (23) of the vortex flow space (15), with the result that particles of the particle-laden water which are picked up by the vortex flow (14) can be separated from the separation section (23).