Impact of Uncertainty of Physical Properties on CO2 Absorption Design

Abstract

The mass transfer coefficients, interfacial area and pressure drop of a packed bed are essential properties that need to be evaluated prior to the design of a CO2 absorption column. Various mathematical models have been proposed to predict these properties under different process conditions. This work has compared several mathematical models for pressure drop, mass transfer coefficients and interfacial area and discussed how the uncertainty of physical properties and process conditions affect the evaluation of packed bed height in a CO2 absorption column. A case study has been performed to study the propagation of uncertainty in input variables through the packed bed height design equations. Here, it was found as 12% from uncertainty in physical properties and 60% from uncertainty in choice of mathematical model of the calculated packed bed height. A recommended safety factor for the absorption packing height is 60 % for a generic packing, but this safety factor can be reduced considerably if experimental data for pressure drop and mass transfer coefficients are available for the specific packing.