ASH BEHAVIOR IN A CFB BOILER DURING COMBUSTION OF COAL, PEAT OR WOOD

This paper presents selected results from an extensive on-site measure ment campaign where the ash behaviour in a 12 MW CFB boiler was studie d during firing of coal, peat and wood. Samples were taken from all in -going (bed material, fuel) and out-going solid material streams (seco ndary cyclone and bag filter) as well as from the bed and the return l eg. Deposit samples were further collected from the cyclone inlet and from two different locations in the convective path. In addition, the boiler operation was monitored, including collection of operational da ta, flue gas temperature profiles and emissions. The paper discusses t he differences in the ash chemistry that were detected between the thr ee different combustion cases and draws conclusions on the impact of t he chemistry on the bed agglomeration and fouling tendency for each fu el. (C) 1997 Elsevier Science Ltd.