Solid foams as efficient catalyst support – fundamental study on heat, mass and momentum transfer (NSC - OPUS 2, No. 2011/03/B/ST8/05455)
Duration: 2012 - 2016
Description
The solid foams have been studied as the structured catalyst carriers for about ten years. Due to their high porosity (void fraction), they display moderate flow resistances accompanied with large specific surface area and intense heat and mass transfer. Foams are made from various materials (ceramics, metal, glass, carbon) enabling various catalyst deposition techniques. Numerous works has appeared dedicated to solid foams, mainly concerning the catalyst deposition and chemical processes performed in heterogeneous gas-solid systems. However, the research on either the heat and mass transfer, or flow resistance, is rather scarce. Important gaps are well visible and there are no results neither theoretical nor experimental for liquid phase. In the criterial numbers various dimensions are used without grounds. The problem of the flow mechanism for foams is not considered in the literature. For example, for a packed bed of grains the models of flow through capillary or flow around the cylinder or sphere are known. Such a models has not been presented for foams. Thus the fundamental aim of the project is to determine the mechanism of fluid flow through foams.
Objectives
The aim of the project is to perform the experimental research and theoretical analysis on the heat, mass and momentum transfer coefficients for the structured catalytic reactor filled with solid foams. Based on the experimental results, the mechanism will be determined that governs the fluid flow through the solid foams. The research hypothesis is the laminar flow developing in a short capillary channel. This kind of mechanism was proven for stacked wire gauzes by authors. The characteristic dimensions in criterial numbers describing transport phenomena might then be the diameter and the length of the foam cell; the problem is not settled yet. Simultaneously, the still insufficient knowledge will be supplemented of the solid foam transport phenomena. The description of the transport phenomena will be based on the theory thus enabling generalization.
