β Scribed by Nearchos J. Christofides; Robert C. Brown
No coin nor oath required. For personal study only.
We are investigating a method for simultaneous determination of devolatilization and char burnout times based on the analysis of CO 2 emissions from a fluidized bed combustor. The technique is nonintrusive and can be performed under realistic combustion conditions. Our method involves batching coal samples in a fluidized bed combustor that is heated with propane gas or other fuel. To validate our technique, control tests were carried out using single-sized coal. Carbon dioxide profiles versus time for the batch tests are analyzed with linear models to obtain characteristic time constants for coal devolatilization and char combustion. The technique gives results that are comparable to times measured by more conventional, visual techniques. Our approach does not require special sample preparation, can be performed in actual combustion equipment, and employs standard boiler instrumentation.
π SIMILAR VOLUMES
A diagnostic modei for the determination of similarity profiles of turbulence and mean-wind gradient in the planetary boundary layer is developed. Vertical profiles of a turbulence length scale and the flux Richardson number are formulated through the extension of the relationships for the constant