NOVELTY - Solid anaerobic and aerobic composting system of organic garbage and sludge, comprises a high-solid anaerobic digester (2), an aerobic compost device (3) and dryer (4). The solid anaerobic digester is installed with a marsh gas purifying device (8). The aerobic compost device is set with a blower (11). The marsh gas purifying device is connected with a marsh gas burning device (9) which is in turn connected with the high-solid anaerobic digester, aerobic compost device and dryer.    USE - The solid anaerobic and aerobic composting system is useful for treating organic garbage and sludge for producing carbon dioxide, methane (claimed), and humus and solid waste product. The produced solid waste product is used as fertilizer. The generated methane is useful for producing electricity.    ADVANTAGE - The solid anaerobic and aerobic composting system treats organic garbage and sludge at suitable temperature and time during reaction process, reduces solid waste content and harmful effects, and inactivates bacteria in the solid waste.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for treating organic garbage and sludge, which involves performing mixing process, anaerobic digestion treatment and aerobic composting process, where the mixing process is performed by subjecting the organic garbage and sludge to the mixer (1) and stirring uniformly, and the anaerobic digestion treatment is performed by adding putting the mixed solid waste with high solid through the anaerobic digester for performing anaerobic digestion to make the solid content of the waste to 20-35%, and finally, the aerobic composting process is performed by subjecting the anaerobic digestion product to the aerobic compost device.    DESCRIPTION OF DRAWING(S) - The drawing shows schematic view of solid anaerobic and aerobic composting system.    Mixer (1)    High-solid anaerobic digester (2)    Aerobic compost device (3)    Dryer (4)    Stirrer (7)    Marsh gas purifying device (8)    Marsh gas burning device (9)    Marsh gas generating device (10)    Blower (11)    Fertilizer production device (12)    Tailing collecting device (13)