Two-liquid propulsive system for an artificial satellite and utilization of said system for ejecting the satellite

A process for controlling a two fuel component, propulsive system for an artificial satellite, in particular for a geostationary satellite to provide advance warning of the end of the normal lifetime of the satellite and to ensure that the satellite is extracted from its operating orbit, the process comprising:

• pressurizing the propellant components contained in the fuel tank of an apogee nozzle and a plurality of low-thrust nozzles for controlling the orientation and the orbit of the satellite,
• achieving an unequl distribution of the propellant supply between at least two pairs of associated tanks with each pair comprising a first component tank and a second component tank, whereby a first pair of tanks contains an excess quantity of a first component relative to the quantity of the second component contained in the associated tank while a second pair of tanks contains an excess quantity of the second component relative to the quantity of the first component contained in the associated tank,
• supplying the first and second components to selected nozzles from said first pair of said tanks until the second component is exhausted,
• supplying the first and second components to selected nozzles from the second pair of tanks until the first component is exhausted and
• switching the supply of first and second components to selected nozzles from the tank of each pair still containing said first and second components in order to provide the satellite with the impulse necessary to extract the satellite from its operating or bit.