Comparing the structural development of sand and rock ilmenite during long-term exposure in a biomass fired 12 MWth CFB-boiler
Artikel i vetenskaplig tidskrift, 2018

Oxygen Carrier Aided Combustion (OCAC) is a novel combustion concept with the purpose to increase the overall efficiency in conventional circulating fluidized bed (CFB) boilers. By replacing the commonly used bed material with an oxygen carrier (OC), the conceptual idea is to utilize the fluid dynamics in a CFB and the inherent oxygen transport supported by the OC to increase the oxygen distribution within the furnace in time and space. The OCAC concept has been successfully validated and further reached long-term demonstration in full scale operation (75-MW th ). This work presents a first evaluation of how ilmenite particles are affected in regard to mechanical resistance during long-term exposure to OCAC conditions in Chalmers 12-MW th CFB-boiler. A sand and a rock ilmenite are evaluated with regard to their mechanical stability. For evaluation, samples of the fresh materials and samples collected during operation in the Chalmers boiler are investigated. The study shows that the two materials differ in how the mechanical degradation occurs with exposure time. The sand ilmenite form cavities which are held together by an ash layer before they are shattered into numerous pieces, whereas the rock ilmenite develops distinct cracks that cause splitting of the particles.

Biomass

Ilmenite

Oxygen carrier aided combustion (OCAC)

Circulating fluidized boiler (CFB)

Författare

Angelica Corcoran

Chalmers, Rymd-, geo- och miljövetenskap, Energiteknik

Pavleta Knutsson

Chalmers, Kemi och kemiteknik, Energi och material, Oorganisk miljökemi

Fredrik Lind

Chalmers, Rymd-, geo- och miljövetenskap, Energiteknik

Henrik Thunman

Chalmers, Rymd-, geo- och miljövetenskap, Energiteknik

Fuel Processing Technology

0378-3820 (ISSN)

Vol. 171 39-44

Ämneskategorier

Kemiska processer

Polymerteknologi

Annan kemiteknik

DOI

10.1016/j.fuproc.2017.11.004

Mer information

Senast uppdaterat

2018-04-05