Preliminary mathematical model for a CO₂ chemical absorption column with amines

Abstract

The design and optimization of absorption columns require models capable of representing coupled phenomena of mass transfer, chemical reaction, liquid-vapor equilibrium, heat transfer, and hydrodynamics. In this work, a preliminary and theoretical formulation of a packed column for chemical CO₂ absorption with amines is proposed, oriented toward its subsequent algebraic implementation in the General Algebraic Modeling System (GAMS) software. The model is built from integral balances of mass, momentum, mechanical and thermal energy applied over a control volume. The liquid-vapor equilibrium and chemical speciation are calculated using the Electrolyte Non-Random Two-Liquid (e-NRTL) physicochemical model previously developed and validated for amine-CO₂-H₂O systems. Likewise, possible correlations available in the literature to estimate stream properties, transfer coefficients, and pressure drop are discussed. Finally, it is proposed that the resulting differential equations must be discretized, transforming the model into a nonlinear algebraic system implementable in GAMS.