Abstract: Method for removal of fouling (14) and/or plugging (13) out of a bundle (11) of channels (12) by treatment with a liquid (2), in particular out of firmly interconnected channels (12), oriented in parallel to each other, as a catalyst module, which can be carried out very quickly and cost effectively, by filling the channels (12) repeatedly and alternately with the liquid (2) from their ends, and draining at least part of the filled in liquid off the same ends.

Abstract: A second reaction medium is introduced into a first reaction medium flowing in a flow channel and the reaction media are intensively mixed. The second reaction medium (which may be one or more reaction media) is introduced at a plurality or even a multiplicity of positions that are distributed over a cross section of the flow channel. Turbulence flow is induced in the first reaction medium (which may also be one or more reaction media) at the positions where the second reaction medium is introduced. As a result, the intense mixing of the reaction media with one another takes place directly at the locations where the second reaction medium is introduced into the flow channel.