Ej. Anthony et al., A NEW MECHANISM FOR FBC AGGLOMERATION AND FOULING IN 100 PERCENT FIRING OF PETROLEUM COKE, Journal of energy resources technology, 119(1), 1997, pp. 55-61
In art effort to clarify the causes of agglomeration and fouling in fl
uidized bed combustion of petroleum coke, a detailed study was made of
samples taken from different locations of an industrial-sized CFBC ba
iler, including deposits formed after 7 and 96 days of operation. It w
as found that vanadium, the suspected cause of the agglomeration, does
not accumulate in fouled regions and that no low melting oxides were
present. Neither could any low melting eutectics be expected from the
vanadium compounds identified Therefore, the high concentrations of va
nadium in the petroleum coke fuel cannot explain the formation of aggl
omerates. Fouling is attributed to molecular cramming effect caused by
the nearly quantitative conversion of the CaO to CaSO4 and the absenc
e of fuel-derived ash providing inert material, which could contribute
discontinuities between the sintered anhydrite grains and prevent mas
sive consolidation of deposits.