The invention relates to a continuously operating process for producing nitrobenzene, comprising the following steps: a) nitriding benzene in adiabatic conditions with sulfuric acid and nitric acid, using a stoichiometric excess of benzene in relation to the nitric acid, in multiple parallel reactors; b) first combining the raw process products of the nitridation from the parallel reactors to form a mixed flow in a device provided specifically for this purpose, then separating the mixed flow into a sulfuric acid phase and a nitrobenzene phase in a downstream phase separation apparatus; and c) processing the nitrobenzene phase, obtaining nitrobenzene. The invention also relates to a production plant suitable for carrying out the claimed process.