Effects of catalytic mineral matter on CO/CO sub 2 ratio, temperature and burning time for char combustion

The temperature of a char particle burning in an oxygen containing atmosphere is the product of a strongly coupled balance between particle size and physical properties, heat transfer from the particle, surface reactivity, CO/CO{sub 2} ratio and gas phase diffusion in the surrounding boundary layer and within the particle. CO{sub 2}/CO ratios can be strongly influenced by catalytic material in the carbon and by the char temperature. In this program we are measuring the CO{sub 2}/CO ratio for both catalyzed and uncatalyzed chars over a wide range of temperature. These results will then be used to develop predictive models for char temperature and burning rates. The electrodynamic balance has been successfully used to make such measurements for single 200 {mu}m spherocarb particles. This work has been previously reported (progress reports 1 and 2). The electrodynamic balance has been rebuilt to improve its performance including: (1) Better control of gas flow and composition, (2) High pressure operation capability, (3) Advanced imaging system for size measurement and position determination (4) Capability of high and low temperature measurement, (5) Better position control, (6) Fast computation and memory facilities, (7) Better laser power control. In this report, progress on the calibration of the imaging system, the laser power control system, and calibration of the mass flowrate controller are reported. 6 figs