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A master's thesis from Aalborg University
Book cover


CFD modelling and optimization of ammonia synthesis-absorption integrated reactor under mild conditions

Term

4. term

Publication year

2025

Submitted on

Pages

28

Abstract

In the Thesis, integrated absorption-enhanced ammonia synthesis is investigated using Computational Fluid Dynamics (CFD) integrated with two kinetic models that describe the synthesis and the absorption. The project is focused on modeling, validating, and optimizing a single-vessel reactor. The absorptionenhanced ammonia synthesis is proposed as a potential sustainable alternative to the conventional Haber Bosch process. The model is validated using experimental data found in the literature. And the accuracy of the CFD model is tested through a grid independence study. A parametric study showed that a configuration that incorporated multiple layers of catalyst and absorbent was capable of achieving hydrogen conversions comparable to those of a single pass in the Haber Bosch process, but at lower operating conditions. Multiple Object Optimization using the central composite design highlighted the critical role of gas hourly space velocity (GHSV) and reactor geometry in balancing conversion efficiency and absorption capacity. The findings confirm that CFD-based modeling is a viable tool for studying ammonia production under renewable energy– compatible conditions, while also emphasizing the need for further experimental validation and economic assessment.