Sorption Transport Models for Indoor Air Quality Analysis

Abstract
Sorption filtration is presently being investigated as one means to control the quality of air in buildings, yet methods to integrate models of sorption filtration devices with multi-zone indoor air quality analysis procedures, to enable rational design of these devices, have not appeared. This paper reviews the theoretical bases of sorption models recently developed for multizone contaminant dispersal analysis and presents new work to extend these models to the problem of sorption filtration modeling. Four generic families of models are presented that account for (1) the equilibrium limits of reversible sorption processes with or without (2) boundary layer diffusion transport at the adsorbent surface and (3) diffusion transport within the adsorbent proper, and, for filtration devices, (4) convection-diffusion transport within the filtration medium. All models are formulated as mass transport elements that may be directly assembled with existing elements to model contaminant dispersal in multizone building/HVAC systems of arbitrary complexity. A comparison of the model families is made, criteria are presented to aid in the selection of the model family to use, and results of first applications of these models are presented that provide some validation of the theory.