NOVELTY - Anaerobic water purification system comprises: an anaerobic water purification unit receiving water to be treated and providing an anaerobic-treated water output; and biomass carriers (120) for supporting anaerobic microorganisms in the anaerobic water purification unit.    USE - The anaerobic water purification system is useful for anaerobic/aerobic water purification (claimed) including waste water treatment.    ADVANTAGE - The anaerobic water purification system utilizes biomass carriers that: allow obviating the conventional three-phase separation, before biogas collection; increase the effective surface area of subsystem and immobilize bacteria, hence preventing wash out and conversion; and significantly reduce the amount of energy required for aeration in aerobic water purification subsystem compared to conventional systems.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) an anaerobic/aerobic water purification system (A1) comprising: an anaerobic water purification subsystem (102) receiving water to be treated and providing an anaerobic-treated water output; and an aerobic water purification subsystem (110) integrated with the anaerobic water purification subsystem, receiving the anaerobic-treated water output and providing an anaerobic- and aerobic-treated water output;    (2) an anaerobic/aerobic water purification system (A2) comprising: an anaerobic water purification subsystem receiving water to be treated, which includes biomass carriers for supporting anaerobic microorganisms, and providing an anaerobic treated water output; and an aerobic water purification subsystem, receiving the anaerobic-treated water output and providing an anaerobic- and aerobic-treated water output;    (3) an anaerobic/aerobic water purification system (A3) comprising: an anaerobic water purification subsystem receiving water to be treated and providing an anaerobic-treated water output; an aerobic water purification subsystem located physically above the anaerobic water purification subsystem, receiving the anaerobic-treated water output and providing an anaerobic- and aerobic-treated water output; and a gas collection volume (124) located above the anaerobic water purification subsystem and below the aerobic water purification subsystem for collecting gas produced by the anaerobic water purification subsystem;    (4) a method (M1) for an anaerobic/aerobic water purification, comprising: anaerobic water purification providing an anaerobic-treated water output; and aerobic water purification integrated with the anaerobic water purification, receiving the anaerobic-treated water output and providing an anaerobic- and aerobic-treated water output;    (5) a method (M2) for an anaerobic/aerobic water purification, comprising: anaerobic water purification utilizing biomass carriers for supporting anaerobic microorganisms and providing an anaerobic-treated water output; and aerobic water purification receiving the anaerobic-treated water output and providing an anaerobic- and aerobic-treated water output;    (6) an anaerobic/aerobic liquid purification system comprising: an anaerobic liquid purification subsystem comprising an inlet for receiving liquid to be treated and an outlet providing an anaerobic-treated liquid output; and an aerobic liquid purification subsystem comprising an inlet for receiving the anaerobic-treated liquid output and an outlet for providing an anaerobic- and aerobic-treated liquid output, where the inlet of the aerobic liquid purification subsystem is connected to the outlet of the anaerobic liquid purification subsystem; and    (7) an anaerobic/aerobic liquid purification comprising: anaerobic purifying of liquid in an anaerobic liquid purification subsystem provided with an anaerobic-treated liquid outlet; aerobic purifying of liquid in an aerobic liquid purification subsystem provided with an inlet for receiving the anaerobic-treated liquid; and integrating the subsystems by connecting the outlet of the anaerobic subsystem to the inlet of the aerobic subsystem.    DESCRIPTION OF DRAWING(S) - The figure shows a simplified illustration of the anaerobic/aerobic water purification system.    Anaerobic water purification subsystem (102)    Aerobic water purification subsystem (110)    Biomass carriers (120)    Gas supply inlet (122)    Gas collection volume (124)