Development of a regenerative sulfur dioxide sorbent system
The absorption and regeneration behaviour of low-cost sorbents to be used for the regenerative desulphurisation of AFBC flue gas was studied. Three sorbent types were selected: natural limestones, agglomerated limestone pellets and barium titanate. Agglomerated limestone pellets appeared to have best absorption and desorption characteristics due to their favourable microstructure. A subgrain model was developed to describe mathematically the sulphation of both natural limestones and agglomerates. The regeneration of calcium sulphate was studied extensively. Strong evidence was found that the regeneration proceeds via a two-step mechanism. In the first step the calcium sulphate is reduced to calcium sulphide. In the second step the calcium sulphide reacts according to an apparent solid-solid reaction with remaining calcium sulphate, yielding calcium oxide and sulphur dioxide. The kinetics of both regeneration steps were studied. The results support the assumed feasibility of a two-step regeneration route that yields concentrated sulphur dioxide.
Bibliographic Reference: EUR 13643 EN (1991) 100 pp., FS, ECU 8.75
ISBN: ISBN 92-826-3020-X
Record Number: 199111476 / Last updated on: 1994-12-02
Original language: en
Available languages: en