Halide aerosols in circulating fluidised bed co-combustion. Role of coal bound kaolin

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)


Interna författare/redaktörer


Publikationens författare: Vainikka P, Silvennoinen J, Taipale R, van Alphen C, Moilanen A, Falcon R, Yrjas P, Hupa M
Förläggare: ELSEVIER SCIENCE BV
Publiceringsår: 2011
Tidskrift: Fuel Processing Technology
Tidskriftsakronym: FUEL PROCESS TECHNOL
Volym: 92
Nummer: 9
Artikelns första sida, sidnummer: 1738
Artikelns sista sida, sidnummer: 1749
Antal sidor: 12
ISSN: 0378-3820


Abstrakt

An experimental campaign was carried out with a circulating fluidised bed (CFB) pilot scale combustor to study the role of coal bound kaolin in the fate of solid recovered fuel (SRF) originated halide aerosols. A combustion experiment was carried out with SRF-Spruce Bark mixture as a reference. High kaolinite coal and paper pigment kaolin, one at a time, were mixed with the SRF-Bark in increasing proportions until dp <1 mu m fine particles were absent as measured from 780 degrees C combustion gases by means of a dilution probe and low pressure impactor (LPI). This fine particle mode was absent after mixing sufficiently either coal or kaolin with SRF-Bark and only traces of water soluble alkali metal salts were found in the CFB fly ash. These conditions were achieved when kaolin was mixed with the SRF-Bark for 52 times on a molar basis compared to the Na + K initially found in the aerosols. This proportioning was found to be the same for the additive kaolin and coal bound kaolinite. Na and K in the fly ash seem to be bound chemically to the kaolin as alkali aluminosilicates rather than in water soluble alkali sulphates. This is indicated by their solubility behaviour.


Nyckelord

Aerosol, Co-combustion, Fine particle, Fluidised bed combustion, Kaolin, Solid recovered fuel

Senast uppdaterad 2019-06-12 vid 03:44