(49a) Mathematical Modeling of Rtsa Using Polymeric/Supported Amine Hollow Fibers-Single Fiber Model

Abstract

The use of novel polymeric hollow fiber contactors loaded with CO₂ adsorbents has been recently demonstrated as a new and scalable process configuration for post-combustion CO₂ capture. The hollow fiber morphology allows coupling of efficient heat transfer with effective gas contacting, potentially giving lower parasitic loads on the power plant compared to traditional contacting strategies using solid sorbents¹. In this study, a two dimensional mathematical model of a rapid pressure swing adsorption (RTSA) process is developed to predict the fiber-sorbent performance during post-combustion CO₂ capture from flue gas. In particular, the model has been developed in several stages moving from simple models with no mass transfer to more complex physical situations with coupled heat and mass transfer between the gas, fiber sorbent and water flow in the bore. The first stage of this project is focused on developing a single fiber model to simulate a three-step RTSA system accounting for adsorption, heating/desorption and cooling steps. The sensitivity of the model to parameter values such as water velocity, initial temperatures, fiber dimension and heat and mass transfer characteristics of polymer, sorbent and water are evaluated accordingly by considering the amount of utility and overall parasitic load on power plant usage for this process. These models are implemented using gPROMS ® version 3 for simulating a complete RTSA cycle. The outcome of the modeling effort is used to guide the experimental team in the development of the fiber and sorbent properties, and to provide input to the techno-economic modeling of the process.

Reference

¹ R.P. Lively et al. Hollow Fiber Adsorbents for CO₂ Removal from Flue Gas, Ind. Eng. Chem. Res. 2009, 48, 7314–7324.