Abstract: An ammonia synthesis process using multi-stage reaction-adsorption coupled method under 3 MPa is proposed. It means that both reaction tower and adsorption tower are divided into three parts, and connected in the form of "reaction 1-adsorption 1-reaction 2-adsorption 2-reaction 3-adsorption 3". The proposed method can break through the limitation of thermal equilibrium, and achieve a higher net ammonia concentration. Aspen Plus software is employed to simulate this process, which is compared with ammonia synthesis processes respectively using 10 MPa Brown method and 3 MPa single-stage reaction-adsorption coupled method under the same ammonia production. It is shown from the results that the process using multi-stage reaction-adsorption method can increase the net ammonia concentration from 6% to 15.04%, drop the reaction tower inlet flow rate by 56.22%, and reduce the power consumption of recycle compressor by 46.37%. It shows a significant effect in energy conservation and emission reduction.
朱明, 梅华. 3 MPa分段式反应吸附耦合的氨合成工艺模拟[J]. 现代化工, 2021, 41(8): 208-213.
ZHU Ming, MEI Hua. Simulation of 3 MPa multi-stage reaction-adsorption coupled process for ammonia synthesis. Modern Chemical Industry, 2021, 41(8): 208-213.
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