ASH SINTERING AND DEPOSIT FORMATION IN PFBC

Agglomerated bed material and deposits from various surfaces in the be d area and in the flue gas duct of pressurized fluidized bed combustio n (PFBC) plants were examined by chemical and X-ray diffraction method s. Crystalline compounds present in the deposits were identified and p ossible mechanisms leading to the formation of bed material agglomerat es, deposits and fouling on surfaces in the flue gas duct are discusse d. The results show that all of the chemical systems CaS-CaSO4-alkali species, silicate-alkali-chlorine and silicate systems containing iron -rich oxides are important in the sintering and fouling process. (C) 1 998 Elsevier Science Ltd. All rights reserved.