Hydrogen sulfide capture by limestone and dolomite at elevated pressure. 2: Sorbent particle conversion modeling
- Aabo Akademi Univ., Turku (Finland). Dept. of Chemical Engineering
The physical structure of a limestone or dolomite to be used in in-bed sulfur capture in fluidized bed gasifiers has a great impact on the efficiency of sulfur capture and sorbent use. In this study an unreacted shrinking core model with variable effective diffusivity is applied to sulfidation test data from a pressurized thermogravimetric apparatus (P-TGA) for a set of physically and chemically different limestone and dolomite samples. The particle size was 250--300 {micro}m for all sorbents, which were characterized by chemical composition analysis, particle density measurement, mercury porosimetry, and BET internal surface measurement. Tests were done under typical conditions for a pressurized fluidized-bed gasifier, i.e., 20% CO{sub 2}, 950 C, 20 bar. At these conditions the limestone remains uncalcined, while the dolomite is half-calcined. Additional tests were done at low CO{sub 2} partial pressures, yielding calcined limestone and fully calcined dolomite. The generalized model allows for determination of values for the initial reaction rate and product layer diffusivity.
- OSTI ID:
- 225473
- Journal Information:
- Industrial and Engineering Chemistry Research, Vol. 35, Issue 3; Other Information: PBD: Mar 1996
- Country of Publication:
- United States
- Language:
- English
Similar Records
Hydrogen sulfide capture by limestone and dolomite at elevated pressure. 1: Sorbent performance
Product layer development during sulfation and sulfidation of uncalcined limestone particles at elevated pressures