Pressure swing adsorption hydrogen extraction is based on the physical adsorption of gas molecules on the internal surface of adsorbent (porous solid material). Using the characteristics that adsorbent is easy to adsorb high boiling point components and difficult to adsorb low boiling point components under the same pressure， the adsorption capacity increases (adsorption part) under high pressure and decreases (desorption part) under reduced pressure， feed gas passes through the adsorbent bed under pressure， The high boiling point impurity components relative to hydrogen are selectively adsorbed， and the hydrogen of low boiling point components is not easy to be adsorbed， but the separation of hydrogen and impurity components is achieved through the adsorbent bed. Then， the adsorbed impurity components are desorbed under reduced pressure to regenerate the adsorbent， so as to facilitate the adsorption and separation of impurities again.

The four adsorption towers of the unit carry out adsorption and desorption preparation process alternately to achieve continuous production of hydrogen. In the process of adsorption desorption， some high-purity oxygen is still retained in the tower after adsorption. This part of high-purity oxygen is used to equalize and flush the other two towers just after desorption. The qualified ammonia dissociation gas passes through the pressure swing adsorption system with alternating operation of the adsorption tower to adsorb and separate all impurities at one time to obtain high-purity finished hydrogen with qualified purity and impurity content.

Main steps of process flow:

Step 1: liquid ammonia raw material is gasified into ammonia at high temperature

Step 2: ammonia purification unit is used to remove water and residual ammonia

Step 3: increase the concentration of decomposed hydrogen through PSA process

Ammonia decomposition hydrogen production equipment (first step)

Ammonia purification equipment (step 2)

Ordinary hydrogen purification (step 3)