NOVELTY - Sulfur tolerant methanation of syngas to replace natural gas, comprises: producing syngas by gasification of raw coal; performing methanation, and discharging crude product gas from top of a slurry bed reactor; separating in a gas-liquid-solid separator, discharging solid phase to perform catalyst regeneration and liquid-phase to recycle inert medium to slurry bed reactor, separating crude product from solid-liquid separator and obtaining qualified gas purified products; and conveying regenerated methanation catalyst into catalyst tank and recycled inert liquid medium to slurry bed reactor.    USE - The method is useful for sulfur tolerant methanation of syngas to replace natural gas (claimed).    ADVANTAGE - The method: exhibits high energy efficiency and low equipment investment and operating costs; and is easily operated.    DETAILED DESCRIPTION - Sulfur tolerant methanation of syngas to replace natural gas, comprises: producing syngas by gasification of raw coal through a gasification furnace; supplying hydrogen to syngas for forming feed gas, compressing, heat transferring, introducing feed gas from bottom of a slurry bed of a gas distributor into a slurry bed reactor equipped with an inert liquid medium and a sulfur tolerant methanation catalyst, performing methanation, discharging the crude product gas from top of the slurry bed reactor, raw gas heat exchanging through the heat exchanger and conveying into a gas-liquid-solid separator for separation; conveying the resulting liquid-solid phase separated from the gas-liquid-solid separator and the inert medium containing catalyst form the bottom of the slurry bed into the liquid-solid separator, discharging the solid phase from the bottom of the liquid-solid separator into the fixed bed catalyst regeneration device to perform catalyst regeneration, separating liquid phase from the liquid-solid separation and discharging into the upper portion of the inert medium storage tank via a pump, which recycles to the slurry bed reactor, and separating the crude product from the solid-liquid separator through the gas heat exchanger and obtaining qualified gas purified products; and conveying regenerated sulfur tolerated methanation catalyst into a catalyst tank and adding recycled inert liquid medium into the slurry bed reactor via the pipeline.