Bag for a circuit of a biological liquid treatment installation

A bag for a circuit of an installation for treatment of a biological liquid by tangential filtration, comprising:

• a plurality of connectors and a network for conveying liquid between said connectors, said conveying network being formed by a plurality of conduits;
• and
• two flexible films fastened to each other, said conduits being formed between the two said flexible films;
• a first conduit extending longitudinally between a flow pump connector emerging on a first side of said bag and a tangential filter connector emerging on a second side of said bag which is an opposite side to said first side;
• a second conduit extending longitudinally from a first side of said conduit between a supply container connector emerging on said first side of said bag, and another tangential filter connector emerging on said second side of said bag which is an opposite side to said first side;
• a third conduit extending from a second side of said conduit, which is an opposite side to said first side of said conduit, starting at a collecting container connector, until it enters said first conduit;
• and
• a fourth conduit extending from the first side of said conduit, starting at a transfer pump connector, until it enters said second conduit;
• whereby said bag is configured such that the liquid to treat passes within said bag via said fourth conduit, then passes to a supply container via said second conduit, then passes as far as the tangential filter by the action of a flow pump via said first conduit, a first treated liquid passing from the tangential filter to the supply container via said second conduit and a second treated liquid passing from the tangential filter to a collecting container via said first conduit.