The reaction between water and partially sulfated lime particles was studied under isothermal conditions using a microcalorimeter. Experiments were performed with spent sorbent particles from two industrial circulating fluidized bed combustors and with lime particles sulfated in the laboratory using a thermogravimetric analyzer. The rate of hydration of the partially sulfated lime particles was found to be independent of particle size, to increase with increasing temperature, and to decrease with increasing level of sulfation of the particles. A first-order kinetic model is shown to correlate well the effect of time and temperature on the extent of hydration of spent sorbent particles from fluidized bed combustors. The apparent activation energy of the hydration reaction is 45 kJ/mol.

Issue Section:
Technical Papers
Keywords:
combustion, fluidised beds, sulphur compounds, calorimetry, water, chemical reactions, sorption, particle size, temperature control
Topics:
Combustion chambers, Fluidized beds, Particle size, Particulate matter, Solids, Temperature, Water, Sorbents
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