Compact device for mixing fluids

A device for mixing fluids for a downflow catalytic reactor (1), said device comprising:

• at least one substantially horizontal collection means (5) provided with a substantially vertical collection conduit (7) for receiving fluids collected by said collection means (5);
• at least one means (8) for injecting a quench fluid opening into said collection conduit (7);
• a mixing chamber (9) located downstream of the collection means (5) in the direction of movement of the fluids, said chamber comprising an inlet end connected directly to said collection conduit (7) and an outlet end (10) for evacuating the fluids;
• and
• a pre-distribution plate (11) comprising a plurality of perforations and comprising at least one riser (13), said plate being located downstream of said mixing chamber (9) in the direction of movement of the fluids;
• characterized in that the section of said mixing chamber (9) is a parallelogram and in that it comprises at least one means (15) for deflection over at least one of the four internal walls of said mixing chamber (9) with a parallelogram section.