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Title: Emissions From Oxy-Combustion of Raw and Torrefied Biomass
Abstract This work assesses the evolution of acid gases from raw and torrefied biomass (distiller’s dried grains with solubles and rice husk) combustion in conventional (air) and simulated oxy-combustion (oxygen/carbon dioxide) environments. Emphasis was placed on the latter, as oxy-combustion of renewable or waste biomass, coupled with carbon capture and utilization or sequestration, could be a benefit toward mitigating global warming. The oxy-combustion environments were set to 21%O2/79%CO2 and 30%O2/70%CO2. Results revealed that combustion of either raw or torrefied biomass generated CO2 emissions that were lower in 21%O2/79%CO2 than at 30%O2/70%CO2, whereas CO emissions exhibited the opposite trend. Emissions of CO from combustion in air were drastically lower than those in the two oxy-combustion environments and those in 21%O2/79%CO2 were the highest. Emissions of NO followed the same trend as those of CO2, while HCN emissions followed the same trend as those of CO. Emissions of NO were higher than those of HCN. The emissions of SO2 were lower in oxy-combustion than in air combustion. Moreover, combustion of torrefied biomass generated higher CO2 and NO, comparable CO and SO2, and lower HCN emissions than combustion of raw biomass. Out of the three conditions tested in this study, oxy-combustion of biomass, either in the raw and torrefied state, attained the highest combustion effectiveness and caused the lowest CO, HCN, and SO2 emissions when the gas composition was 30%O2/70%CO2.  more » « less
Award ID(s):
1810961
PAR ID:
10169681
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Energy Resources Technology
Volume:
142
Issue:
12
ISSN:
0195-0738
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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