NOVELTY - Hydrogen-carbon ratio control system comprises numerous or distributed gas methanation reactor, supplementary methanation reactor, carbon monoxide-enriched air inlet pipeline, hydrogen gas-enriched air inlet pipeline, 1st control valve, 2nd control valve, and main pipeline in which numerous or distributed gas methanation reactor is connected to supplementary methanation reactor through main pipeline, and carbon monoxide-enriched air inlet pipeline and hydrogen gas-enriched air inlet pipeline are arranged in parallel and intersected to main pipeline.    USE - Hydrogen-carbon ratio control system (claimed).    ADVANTAGE - System has simple structure and precised control, process is simple and fast, and product has better quality.    DETAILED DESCRIPTION - Hydrogen-carbon ratio control system comprises numerous or distributed gas methanation reactor, supplementary methanation reactor, carbon monoxide (CO)-enriched air inlet pipeline, hydrogen gas (H2)-enriched air inlet pipeline, 1st control valve, 2nd control valve, and main pipeline in which numerous or distributed gas methanation reactor is connected to supplementary methanation reactor through main pipeline, CO-enriched air inlet pipeline and H2-enriched air inlet pipeline are arranged in parallel and intersected to main pipeline, 1st control valve is located on track of CO-enriched air inlet pipeline, and 2nd control valve is located on track of H2-enriched air inlet pipeline. An INDEPENDENT CLAIM is included for use of hydrogen-carbon ratio control system which involves discharging reaction gas from numerous or distributed gas methanation reactor through 1st control valve or 2nd control valve, regulating, adding CO-enriched and H2-enriched distributed gas, and entering into supplementary methanation reactor.    DESCRIPTION OF DRAWING(S) - The drawing shows an additional schematic diagram of hydrogen-carbon ratio control system.    Online analysis device (8)    1st bypass pipeline (9)    2nd bypass pipeline (10)    1st bypass valve (11)    2nd bypass valve (12)