And waste heat utilization rate can be improved

The utility model discloses a synthetic ammonia production system capable of improving the waste heat utilization rate. Desulfurized natural gas and steam are introduced into a natural gas and steam mixer, the natural gas and steam mixer is connected to a second-section converter through a first mixed gas pipeline, and a first mixed preheater, a second mixed preheater and a heat exchange type first-section converter are further sequentially connected to the first mixed gas pipeline in series; and the reaction gas after the reaction in the second-stage conversion furnace is introduced into theconversion waste gas boiler through a reaction gas pipe. The first mixed gas pipeline is also sequentially connected with two mixed preheaters in series; the waste heat of the reaction gas dischargedfrom the two-stage furnace is recovered to the maximum extent; the temperature of the mixed gas inlet of the heat exchange type first-stage reforming furnace is effectively increased, the reaction efficiency in the heat exchan