Hot Coal Gas Desulfurization With Manganese-Based Sorbents
- Dept. of Civil Engineering, Univ. of Minnesota, Minneapolis, MN (United States)
The objective of this project is to develop a pellet formulation which is capable of achieving low sulfur partial pressures and a high capacity for sulfur, loaded from a hot fuel gas and which is readily regenerable. Furthermore the pellet must be strong for potential use in a fluidized and regenerable over many cycles of loading and regeneration. Regeneration should be in air or oxygen-depleted air to produce a high-concentration sulfur dioxide. Fixed-bed tests were conducted with several formulations of manganese sesquioxide and titania, and alumina. They were subject to a simplified fuel gas of the oxygen-blown Shell type spiked with a 30,000 ppmv concentration of H{sub 2}S. Pellet crush strengths for 4 and 2 mm diameter pellets was typically 12 lbs per pellet and 4 lbs per pellet, respectively. For the most favorable of the formulations tested and under the criteria of break-through at less than 100 ppmv H{sub 2}S and loading temperatures of 5000 {degrees}C and an empty-bed space velocity of 4, 000 per hour, breakthrough occurred an effective loading of sulfur of 27 to 29% over 5 loading and regeneration cycles. At 90% of this saturation condition, the observed level of H{sub 2}S was below 10 ppmv. For regeneration, a temperature of 9000 {degrees}C is required to dissociate the sulfide into sulfur dioxide using air at atmospheric pressure. The mean sulfur dioxide concentration which is achieved during regeneration is 8% with empty-bed space velocities of 700/hr. TGA tests on individual pellets indicate that bentonite is not desirable as a bonding material and that Mn/Ti ratios higher than 7:1 produce relatively non-porous pellets. Whereas the reactivity is rapid below 12% conversion, the kinetics of conversion decreased significantly above this level. This observation may be the result of plugging of the pellet pores with sulfided product creating inaccessible pore volumes or alternately an increase in diffusional resistance by formation of MnS.
- Research Organization:
- USDOE Morgantown Energy Technology Center (METC), WV (United States)
- Sponsoring Organization:
- USDOE Assistant Secretary for Fossil Energy, Washington, DC (United States)
- DOE Contract Number:
- FG22-94PC94212
- OSTI ID:
- 420302
- Report Number(s):
- DOE/PC/94212-97/C0730; CONF-960757-22; ON: DE97051027
- Resource Relation:
- Conference: Advanced coal-fired power systems review meeting, Morgantown, WV (United States), 16-18 Jul 1996; Other Information: PBD: [1996]
- Country of Publication:
- United States
- Language:
- English
Similar Records
KINETICS OF Mn-BASED SORBENTS FOR HOT COAL GAS DESULFURIZATION
Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly report, December 15, 1993--March 15, 1997
Related Subjects
40 CHEMISTRY
HOT GAS CLEANUP
SORBENT RECOVERY SYSTEMS
COAL GAS
DESULFURIZATION
MANGANESE OXIDES
SORPTIVE PROPERTIES
HYDROGEN SULFIDES
ABSORPTION
SULFUR
PELLETS
SULFUR DIOXIDE
FLUIDIZED-BED COMBUSTION
TEMPERATURE DEPENDENCE
EXPERIMENTAL DATA
TITANIUM OXIDES
ALUMINIUM OXIDES