Hydrogen sulfide capture by limestone and dolomite at elevated pressure. 2: Sorbent particle conversion modeling

Journal Article · Fri Mar 01 04:00:00 EST 1996 · Industrial and Engineering Chemistry Research

DOI:https://doi.org/10.1021/ie950539j· OSTI ID:225473

Zevenhoven, C A.P.; Yrjas, K P; Hupa, M M ^[1]

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1. 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, Journal Name: Industrial and Engineering Chemistry Research Journal Issue: 3 Vol. 35; ISSN IECRED; ISSN 0888-5885
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
ADSORBENTS
CALCINATION
CARBON DIOXIDE
DOLOMITE
FLUIDIZED BEDS
GAS GENERATORS
HYDROGEN SULFIDES
LIMESTONE
MATHEMATICAL MODELS
MORPHOLOGY
REMOVAL
SORBENT INJECTION PROCESSES
SULFIDATION
THERMAL GRAVIMETRIC ANALYSIS