Hydrodynamics of gas-solid fluidization at ultra-high temperatures

Abstract

The interest in processing granular materials in fluidized beds at ultra-high temperatures has grown recently to reduce energy consumption and CO2 emissions in relation to numerous high-temperature solid-state reactions. The present research focuses on understanding the hydrodynamics of gas-solid fluidization at temperatures up to 1650 °C to aid the development of ultra-high temperature fluidized bed reactors. Experiments are conducted in a fluidized bed of 30 mm diameter at temperatures up to 1650 °C with corundum and magnesite oxide particles. The fluidization stability is examined based on bed pressure drop measurements using a non-isothermal experimental method. The results demonstrate that stable fluidization of these particles at ultra-high temperatures can be attained by using particles of large and broad size distribution and operating at sufficiently high gas velocities. This article also discusses the bed pressure drop fluctuation, minimum fluidization velocity, and pressure drop offset at ultra-high temperatures.