Direct reduction method for producing sponge iron by transforming from hydrocarbon-rich gas

The invention relates to a direct reduction method for producing sponge iron by transforming from hydrocarbon-rich gas, and belongs to the technical field of metallurgy. According to the invention, a non-catalytic pure oxygen transforming process is adopted for raw material gas transforming and reforming, a partial oxidation method is adopted for heating, and a traditional high-temperature tubular heating furnace is abandoned, so that the problem of carbon precipitation is avoided while the investment is reduced and the heat transfer efficiency is improved; meanwhile, the requirement for the variety of the feed gas is wide, a catalyst is not needed in the reforming and transforming reaction, complex pretreatment before transforming of the feed gas is omitted, and the problem that the catalyst loses efficacy due to impurity components is solved. The furnace top gas of the shaft furnace is recycled, the heat of the high-temperature furnace top gas is effectively recovered and fully utilized by adopting a high-t