(611b) Chemical Looping Processes: Role of Particle Science and Technology

                                                                                                                                       Chemical Looping Processes: Role of Particle Science and Technology

by

L.- S. Fan

Department of Chemical and Biomolecular

Engineering

The Ohio State University

Columbus, Ohio 43210

Abstract

The concept of chemical looping reactions has been applied to processes used in chemical industries. Fundamental and applied research on chemical looping reactions in energy systems has been extensively carried out. Fossil fuel chemical looping applications started with the steam-iron process using syngas from coal as feedstock in the 1900s through the 1940s and were demonstrated at a pilot scale with the carbon dioxide acceptor process in the 1960s and 1970s. There are presently no chemical looping processes using carbonaceous fuels in commercial operation. However, with CO₂ emission from fossil fuel usage that is now of great concern, interest is high in chemical looping technology applications for CO₂ capture.

Chemical looping technology is a manifestation of the interplay among all the key elements of particle science and technology including particle synthesis, reactivity and mechanical properties, flow stability and contact mechanics, gas-solid reaction engineering and particulates system engineering. This presentation will describe the fundamental and applied aspects of modern chemical looping technology that utilizes fossil and other carbonaceous feedstock. Specifically, it will discuss the characteristics of fluidized bed and moving bed and their impact on the metal oxide conversion in the reducer operation – the key operation - of the chemical looping processes. The energy conversion efficiency and economics of the Coal-Direct Chemical Looping Process and Syngas Chemical Looping Process being developed at Ohio State University based on the moving bed configuration will also be elaborated.