Temperature Analysis of a Class of Electroheated Fluidised Beds

Abstract

Fluidisation is an important phenomenon which is used in many chemical and physical processes where heat is a salient factor. In this investigation, practical mathematical models for an important class of electrically-heated fluidised beds have been established. Experimental work was conducted upon laboratory pilot plant and the validity of the derived analytic models has been checked experimentally. These models cater, for the first time, for the (heating and cooling) mode dependence and flow dependence of both directly and indirectly heated fluidised beds. The parameters of these models can be established by a simple series of tests. These models greatly simplify the analysis of existing fluidised bed processes and prediction of the performance of proposed processes. New flow diagrams were then derived; these give important conceptual insights into the operation of thermal systems. Using these flow diagrams, new steady-state temperature analysis techniques were developed for preheated fluidised beds. These facile techniques greatly simplify temperature analysis within steady-state fluidised beds, and readily evaluate the thermal saving of each stage in a preheated fluidised bed.