Sulfur retention in an oxy-fuel bubbling fluidized bed combustor: Effect of coal rank, type of sorbent and O 2 /CO 2 ratio

Abstract

In this work, SO 2 retention via calcium-based sorbents added in a continuous bubbling 17 fluidized bed combustor (~3 kWth) operating in oxy-fuel combustion mode is analyzed. 18Tests were performed at different operating temperatures with three sorbents, two 19 limestones and one dolomite, and with three coals, ranging from lignite to anthracite, to 20 analyze the influence of coal rank, type of sorbent, sorbent particle size, and O 2 /CO 2 21 feeding ratio on the sulfation process. 22It was found that the combustor temperature had a strong influence on the limestones 23 sulfur retention with a maximum at 900-925 ºC. The behavior of the limestones was 24 qualitatively similar with the three coals, attaining the highest sulfur retention values 25

Morphological analysis of sulfated Ca-based sorbents under conditions corresponding to oxy-fuel fluidized bed combustion

“…5). Previous studies demonstrated that dolomites are able to reach high sulfation conversions, near 1 with respect to Ca content, both in calcining and noncalcining conditions during oxyfuel combustion in fluidized beds [24], as observed in Fig. 3.…”

Oxyfuel combustion for CO2 capture in power plants

“…There are several review papers (Buhre et al, 2005;Tan et al, 2005;Wall, 2007;Wall et al, 2009;Normann et al, 2009;Toftegaard et al, 2010;Davidson and Santos, 2010;Scheffknecht et al, 2011;Stanger and Wall, 2011;Chen et al, 2012;Lockwood, 2014) and books (Zheng, 2011;Toporov, 2014) published in the open literature. All of them have provided comprehensive information about the different aspects of oxy-PC combustion.…”

“…Simplified schematic flow diagram of oxy-PC coal fired power plant with CO2 capture, including possible locations for flue gas recirculation and O2 addition -adapted fromDavidson and Santos (2010).…”

A review of oxy-fuel combustion in fluidized bed reactors

“…Conversely, the N 2 O emission decreased with the increase in operating temperature. In a subsequent study, de las Obras‐Loscertales et al evaluated SO 2 retention by three different calcium‐based sorbents (a dolomite and two limestones). Tests were respectively performed with three different coal types (lignite, bituminous and anthracite) at different operating temperatures to evaluate the influence of sorbent type and particle size, coal rank, temperature and O 2 /CO 2 feed ratios on sulfation.…”

“…De las Obras‐Loscertales et al reported experimental results conducted in a 3 kWth BFB furnace under oxy‐combustion atmosphere, where sulfur retention through Ca‐based sorbents and the influence of coal rank were studied. The limestone was observed to have a greater sulfur retention capability when combustion temperature was increased to about 925 °C.…”