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Bubble Transport in Fluidized-Bed Combustion

One of the technologies in development at NETL is fluidized-bed combustion, an environmentally friendly system to burn biomass in a powdered bed by heating it from the bottom in a cylinder. This combustion process can use virtually any fuel and burn it efficiently.

PSC and NETL scientists collaborated to simulate this process using sophisticated software, called MFIX. In one animation from these computations (top), color corresponds to the percentage of gas versus solid, as the powdered fuel (red) in the bottom of the cylinder heats and forms bubbles that rise into the upper-half (blue) of the cylinder.

An important objective of fluidized-bed combustion is minimizing ozone emissions, and the simulation tracks ozone as it rises — to see if it escapes the cylinder. In another animation (bottom) shown here, color represents relative ozone concentration. This is the first 3D simulation of this process, and it shows asymmetries in the gas plume rising from the bed, which couldn't be detected in earlier 2D simulations.