NOVELTY - A batch production system of bio-methane using wet fraction organic municipal solid waste (MSW) comprises segregator subs-system (100) which contains fractionalizer and air density separator and adaptably separates MSW in dry faction, wet fraction and inert fraction, modular digestion sub-system (300) which receives feed from segregator sub-system and has automatic sealing unit and digesters and collection unit, and automatic purification sub-system (400) which connects with collection unit to purify evolved biogas into 91-93% bio-methane.    USE - A system for batch production of bio-methane using wet fraction organic municipal solid waste (MSW) (claimed).    ADVANTAGE - System is efficient even at places having low/sub-zero atmospheric temperature.    DETAILED DESCRIPTION - A batch production system of bio-methane using wet fraction organic municipal solid waste (MSW) comprises segregator subs-system (100) which contains fractionalizer and air density separator and adaptably separates MSW in dry faction, wet fraction and inert fraction, modular digestion sub-system (300) which receives feed from segregator sub-system and has automatic sealing unit and digesters and collection unit, and automatic purification sub-system (400) which connects with collection unit to purify evolved biogas into 91-93% bio-methane and has housing configured with balloon coupled with slidable ring and sensors and purifier. Automatic sealing unit has overhead tank coupled with ball valve, overflow pipe, collection tank and pump. Overhead tank is adaptably configured in-line at digesters through ball valve and digesters of modular digestion sub-system connected to collection tank through overflow pipe. Modular digester (250) has inner tank (220) and flexible lid to facilitate anaerobic digestion. Collection unit is coupled with flexible lid and collects evolved biogas from each modular digester. An INDEPENDENT CLAIM is included for a batch production of bio-methane gas using wet fraction MSW which involves collecting and segregating MSW in dry fraction, wet fraction and inert fraction using segregator sub-system, layering of 1st layer containing mixture A having mother culture, water and alkali flakes, adding segregated wet from fraction from segregator sub-system over 1st layer, layering 2nd layer having mixture B containing mother culture and alkali flakes, allowing anaerobic digestion of water submerged contents by anaerobically sealing the inner tank for 70-120 days, layering 3rd layer having mixture C containing digested sludge, mother culture, water and alkali flakes, allowing anaerobic digestion of mixture C for 70-120 days, collecting evolved biogas and removing digested sludge from modular digester, refilling modular digester with 1st layer having mixture D containing mother culture, water and alkali flakes, adding segregated wet fraction over 1st layer containing mixture D, layering 2nd layer having mixture E containing mother culture and alkali flakes, allowing anaerobic digestion of water submerged contents for 70-120 days, and purifying evolved biogas from modular digester by subjecting biogas in automatic purification sub-system to produce purified bio-methane.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the system for batch production of bio-methane using wet fraction organic waste and cross-sectional view of the modular digestion subs-system.    Segregator subs-system (100)    Inner tank (220)    Modular digester (250)    Modular digestion sub-system (300)    Automatic purification sub-system (400)