Intraparticle mass transfer during sulfation by calcined limestone

Conference · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5755775

Simons, G A; Garman, A R

Current sulfation models describe the intraparticle diffusion of SO/sub 2/ through porous CaO, the intrinsic kinetics of the CaO + SO/sub 2/ reaction, the buildup of the product layer (CaSO/sub 4/), and the subsequent particle deactivation due to the relatively slow diffusion of SO/sub 2/ through the CaSO/sub 4/ to the unreacted CaO. These models are analyzed and their results suggest an alternative deactivation mechanism: the plugging of the smallest pores and the associated loss in internal surface area. A pore plugging model is developed which is compatible with a tree-like description of pore branching. The model is validated with both SO/sub 2/ and H/sub 2/S sorption data without invoking any adjustable parameters, such as the product layer diffusion coefficient. For the cases considered, small pore plugging is always the dominant particle deactivation mechanism. 31 refs., and 11 figs.

• Research Organization: Physical Sciences, Inc., Andover, MA (USA)
• DOE Contract Number: AC21-84MC21388
• OSTI ID: 5755775
• Report Number(s): CONF-850810-14; ON: DE85008543
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
014000* -- Coal
Lignite
& Peat-- Combustion
ALKALINE EARTH METAL COMPOUNDS
CALCINATION
CALCIUM COMPOUNDS
CALCIUM OXIDES
CALCIUM SULFATES
CARBONACEOUS MATERIALS
CARBONATE ROCKS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COAL
COMBUSTION
DEACTIVATION
DECOMPOSITION
DIFFUSION
ENERGY SOURCES
FLUIDIZED-BED COMBUSTION
FOSSIL FUELS
FUELS
KINETICS
LIMESTONE
MATERIALS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PYROLYSIS
REACTION KINETICS
ROCKS
SEDIMENTARY ROCKS
SULFATES
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
THERMOCHEMICAL PROCESSES