Method of separating a composite liquid into at least two components

A method for separating a composite liquid into at least a first component and a second component, comprising:

• centrifuging a separation bag contained in a fixed volume separation compartment, the separation bag comprising a first volume and containing a content comprising a second volume of the composite liquid and a residual volume of a gas so as to cause the sedimentation of at least the first component and the second component in the separation bag, wherein the first volume is different from the second volume;
• displacing a volume of a hydraulic fluid against the separation bag comprising:
• applying a pressure onto the separation bag;
• causing a transfer of the volume of the gas contained in the separation bag into at least one component bag;
• and
• causing a transfer of a first fraction of the content of the separation bag into a first component bag connected to the separation bag;
• determining a volume of the hydraulic fluid being displaced so as to cause the transfer of the gas until the first fraction of the content of the separation bag starts to transfer into the first component bag;
• and
• determining the second volume of the composite liquid in the separation bag from the fixed volume of the separation compartment, and the determined volume of the hydraulic fluid being displaced so as to cause the transfer of the gas until the first fraction of the content starts to transfer into the first component bag.