Theoretical progress in treating the flue gas with ceramic membranes

Abstract

The ceramic membrane separation is the key technology to solving problems caused by the moisture and the waste heat recovery from the wet flue gas. It involves research contents of the condensation, the transmembrane process and the irreversibility. This work summarizes problems in these three aspects, provides corresponding solutions based on the research status, and hopes to solve problems by combining experiments and numerical simulations. Aiming at the condensation characteristics, the critical criterion for the condensation mode conversion of the wet flue gas inside pores will be defined, followed by the characterization of the temporal and the spatial distribution of the condensate so as to shed light on limitations of the theoretical strengthening of the condensation heat transfer. Aiming at the transmembrane process, a theoretical model of the heat and mass coupled transfer will be developed. Constitutive relations between transfer fluxes and driving forces under steady and unsteady conditions will be analyzed to reveal mechanisms of the heat and mass coupled transfer in the physical field. Aiming at the irreversibility, a comprehensive efficiency evaluation model will be generated for the heat and the moisture recovery of multi-stage ceramic membrane modules covering irreversible losses, and to determine the matching relationship between the energy flow and the material flow. The novelty of this work is clarifying the heat and mass transfer problem under the physical scenario of treating the wet flue gas by ceramic membranes, which may provide references for the future research in this field.