Sulfur and sorbent performance in pressurized fluidized-bed combustion of gasification residue

Book · Sat Dec 30 23:00:00 EST 1995

OSTI ID:287962

Hippinen, I T; Kudjoi, A S; Jahkola, A K ^[1]

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1. Helsinki Univ. of Technology, Espoo (Finland). Dept. of Energy Engineering

In second generation pressurized fluidized-bed processes the fuel is partially gasified in a fluidized-bed and the solid residue, containing unburned carbon, is led to atmospheric or pressurized fluidized-bed combustion. Calcium-based sulfur absorbent, i.e. limestone or dolomite, can be fed to the gasifier, where it reacts with hydrogen sulfide (H{sub 2}S) forming mainly calcium sulfide (CaS). The calcium sulfide is unstable and must be oxidized to calcium sulfate (CaSO{sub 4}). The gasification residue, including the used absorbent, is fed to the FB combustor, where the sulfide is oxidized. In addition, some of the fuel sulfur will stay in the fuel during the gasification and this sulfur should also be bound to the solids. This paper presents the results of experimental work dealing with the sulfur and calcium compounds in the PFB combustion of gasification residue. The studies have been carried out at helsinki University of Technology with a 130 kW{sub th} PFBC test rig. Cyclone fines and bed char from a pilot scale PFB gasifier have been burned at 0.6 and 1.0 MPa pressures. The oxygen concentration in the flue gas was 0.1 to 10.3% and the bed temperature was 680 to 920 C. The fluidizing velocity was 0.3 to 0.6 m/s. The results show that the sulfur stays in the solids. The measured sulfur dioxide emissions were around 30 ppm. The solid analyses show that most of the sulfide oxidized to other compounds and that sulfide contents of the removed solids were mainly low.

• OSTI ID: 287962
• Report Number(s): CONF-950522--; ISBN 0-7918-1305-3
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
AIR POLLUTION ABATEMENT
CALCIUM CARBONATES
CALCIUM SULFATES
CALCIUM SULFIDES
CHARS
COAL GASIFICATION
COMBINED-CYCLE POWER PLANTS
EXPERIMENTAL DATA
FLUIDIZED-BED COMBUSTION
FLUIDIZED-BED COMBUSTORS
GAS GENERATORS
HOT GAS CLEANUP
HYDROGEN SULFIDES
OXIDATION
PERFORMANCE
PRESSURIZATION
SORBENT INJECTION PROCESSES
SULFIDATION
SULFUR DIOXIDE
TEST FACILITIES