A mobile system for separating donor blood by gravitational force into erythrocyte concentrate and plasma. The system includes a first bag serving as a reservoir for the blood to be separated and at least a second and third bag for respectively receiving the erythrocyte concentrate and plasma, and also multiple tubes for connecting the flexible bags to a separator module having a separating membrane in the form of a bundle of hollow fibers. This system is divided into at least one first and one second sterilely packaged, individual subsystem. The first subsystem includes the individual bags and associated connection tubes and the second subsystem includes the separator module, and male/female connectors.
