The invention concerns a device comprising: a base (2)； a moveable or removable door (20), said device having a closed door position； and in the closed door position, a circuit (8) comprising a bag comprising two flexible films and conveying network connectors, and a press (9) comprising a first shell (16) disposed on said front face (5) of said base (2) and a second shell (17) disposed in said door (20)； said bag being clamped between said first shell (16) and said second shell (17) in a state in which conduits of said network for conveying liquid are formed between said films.
