ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
PUBLISHED
SINCE 1984
 
Oil Shale cover
Oil Shale
ISSN 1736-7492 (Electronic)
ISSN 0208-189X (Print)
Impact Factor (2020): 0.934

FULL-SCALE TESTS ON THE CO-FIRING OF PEAT AND OIL SHALE IN AN OIL SHALE FIRED CIRCULATING FLUIDIZED BED BOILER; pp. 250–262

Full article in PDF format | https://doi.org/10.3176/oil.2017.3.04

Authors
TÕNU PIHU, ALAR KONIST, DMITRI NESHUMAYEV, LAURI LOO, ARTJOM MOLODTSOV, ALEKSANDR VALTSEV

Abstract

The paper presents analysis of data obtained from tests of oil shale (OS) and peat co-combustion in a full-scale 250 MWth (useful heat output) circulating fluidized bed (CFB) boiler. The tests were conducted at nominal boiler load, with peat thermal input up to 30%. During the experiments, gas analysis was performed and ash samples were collected. The specific con­sumption of the oil shale and peat blend per useful heat and gross electricity was calculated and other techno-economic characteristics were determined.
   It was found that the co-combustion of oil shale and wet peat increased the CO emission to the level of 60 mg/Nm3. The NOx concentration increased from 120 to 165 mg/Nm3. The SO2 and HCl emissions remained at a very low level – below 20 mg/Nm3. A significant ash reduction, approximately 4%, was measured in the case of a 30% peat content. Due to the high peat moisture, the flue gas volume increased 5–10%. As a result of addition of peat, the content of particulate matter (PM) 10/2.5 was also lower than that by conventional oil shale CFB firing. Oil shale and peat co-combustion can be considered as a viable option and near-term solution for reducing the environmental impact of oil shale power production.


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