System for preparing hydrogen by using natural gas

The utility model discloses a system for preparing hydrogen by using natural gas, which comprises a desulfurizing tower, a hydrogen conversion furnace, a waste heat boiler, a secondary furnace, a desalted water preheater, a converted gas water cooler, a steam-water separator and a pressure swing adsorption device, the natural gas compressor is connected with the natural gas buffer tank through a first pipeline; the system is reliable in operation, the two converters are arranged in the system for preparing the hydrogen from the natural gas, so that carbon monoxide in the converted gas with reduced temperature and water vapor are subjected to a conversion reaction in the two converters to generate CO2 and H2, the proportion of the hydrogen in the converted gas is further improved, the hydrogen with the purity of 99.9% is produced, and the system is short in technological process, almost non-toxic and low in cost. Equipment and facility investment is low, occupied area is small, and safe and stable production i