Preheating spiral feeding device

The invention relates to the field of industrial biomass gasification furnaces, in particular to a preheating spiral feeding device, and aims to solve the problems that biomass fuel needs to be preheated when entering a gasification furnace, and fuel gas discharged from the gasification furnace is high in temperature, high in tar content and the like. The fuel gas purification device comprises a screw rod, a screw cylinder, a fuel gas purifier, a power device, bearings, a lubricating structure, a fuel inlet, a fuel outlet, a fuel gas inlet, a fuel gas outlet, a tar outlet and other elements, and is characterized in that the screw rod is arranged in the screw cylinder, the screw rod is provided with screw blades, and the two ends of the screw rod are provided with the bearings; one end of the screw rod is connected with a power device through a coupling, and the screw cylinder is sleeved in the gas purifier; the working principle is as follows: high-temperature fuel gas from the gasification furnace is subject