60万t/a合成氨系统变换装置“零蒸汽”消耗优化设计

Design Optimization of “Zero Steam” Consumption of the Shift Unit in 600 kt/a Ammonia System

4.0MPa(g)粉煤气化的粗煤气CO干基含量在65%(v)以上,而水气比一般在0.8左右。为了满足合成氨装置中合成气的CO干基含量在0.4%(v)左右的要求,需要向变换装置补充大量的水(或水蒸气)来提高水气比。针对这一特点,通过对变换装置热量回收方案的优化设计,实现整个装置零蒸汽补入,达到节能降耗的目的。

The CO content(dried basis)in crude syngas after pulverized coal gasification at 4.0MPa(g)is above 65%(v),while the water-vapor ratio is normally about 0.8.In order to meet the requirement of 0.4%(v)CO content(dried basis)in the syngas of ammonia plant,a large amount of water(or steam)must be supplied to the shift plant to increase the water-vapor ratio.Against this backdrop,the scheme of heat recovery of shift plant was optimized to achieve zero steam replenishment of the whole plant for the purpose of energy saving and consumption reduction.