NOVELTY - A biogas closed ecological water purification system contains anaerobic fermentation system (1), 1st gas flow meter (2), integrated data collection system (3), 1st gas line monitoring system (4), biogas storage system (5), nano-membrane gas distribution system (6), diatoms (7), carbon dioxide adsorption tank (8), microaerobic bio-filtration system (9), drying system (10), 2nd gas flow meter, and 2nd gas line monitoring system.    USE - A biogas closed ecological water purification system (claimed).    DETAILED DESCRIPTION - A biogas closed ecological water purification system contains anaerobic fermentation system (1), 1st gas flow meter (2), integrated data collection system (3), 1st gas line monitoring system (4), biogas storage system (5), nano-membrane gas distribution system (6), diatoms (7), carbon dioxide adsorption tank (8), microaerobic bio-filtration system (9), drying system (10), 2nd gas flow meter, and 2nd gas line monitoring system, anaerobic fermentation system in turn connected to 1st gas flow meter, 1st gas line monitoring system, biogas storage system, carbon dioxide adsorption tank storage system, diatoms, and nano-membrane gas distribution system, 1st gas flow meter, 2nd gas flow meter, 1st gas line monitoring system, 2nd gas line monitoring system, and data acquisition system are connected to integrated data collection system, carbon dioxide adsorption tank is connected to microaerobic bio-filtration system, drying system, 2nd gas flow meter, 2nd gas line monitoring system, and gas discharging device (11).    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram of biogas closed ecological water purification system.    Anaerobic fermentation system (1)    1st gas flow meter (2)    Integrated data collection system (3)    1st gas line monitoring system (4)    Biogas storage system (5)    Nano-membrane gas distribution system (6)    Diatoms (7)    Carbon dioxide adsorption tank (8)    Microaerobic bio-filtration system (9)    Drying system (10)    Gas discharging device (11)