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Title: Reactivation properties of four long-term sulfated limestones

Abstract

Four Canadian limestones - Cadomin, Havelock, Kelly Rock, and Graymont - were investigated for their reactivation properties after long-term sulfation. Each limestone was initially sulfated with 1% SO{sub 2} at 850{sup o}C in a tube furnace for a relatively long time (about 16 h), to achieve an effectively maximally sulfated sample. The samples were subsequently hydrated with liquid water and steam at various conditions to reactivate the unreacted CaO. The hydrated samples were resulfated in a thermogravimetric analyzer for 90 min to evaluate the effect of hydration on the resulfation step. All four samples were significantly reactivated by steam hydration, which was much more effective than was hydration with liquid water, and the overall calcium utilization increased to 80-90% after reactivation, compared to 25-45% typical before reactivation. A scanning electron microscope was used to analyze Cadomin and Havelock samples, and both were uniformly sulfated before hydration. This work indicated that the uniformly sulfated samples could be reactivated given suitable hydration conditions.

Authors:
; ;  [1]
  1. CANMET Energy Technology Centre-Ottawa, Ottawa, ON (Canada). Natural Resources Canada
Publication Date:
OSTI Identifier:
20838256
Resource Type:
Journal Article
Resource Relation:
Journal Name: Energy and Fuels; Journal Volume: 20; Journal Issue: 6; Other Information: ywu@nrcan.gc.ca
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; LIMESTONE; SULFATION; CHEMICAL ACTIVATION; HYDRATION; THERMAL GRAVIMETRIC ANALYSIS; STEAM; SCANNING ELECTRON MICROSCOPY; FLUIDIZED-BED COMBUSTION

Citation Formats

Yinghai Wu, Edward J. Anthony, and Lufei Jia. Reactivation properties of four long-term sulfated limestones. United States: N. p., 2006. Web.
Yinghai Wu, Edward J. Anthony, & Lufei Jia. Reactivation properties of four long-term sulfated limestones. United States.
Yinghai Wu, Edward J. Anthony, and Lufei Jia. Fri . "Reactivation properties of four long-term sulfated limestones". United States. doi:.
@article{osti_20838256,
title = {Reactivation properties of four long-term sulfated limestones},
author = {Yinghai Wu and Edward J. Anthony and Lufei Jia},
abstractNote = {Four Canadian limestones - Cadomin, Havelock, Kelly Rock, and Graymont - were investigated for their reactivation properties after long-term sulfation. Each limestone was initially sulfated with 1% SO{sub 2} at 850{sup o}C in a tube furnace for a relatively long time (about 16 h), to achieve an effectively maximally sulfated sample. The samples were subsequently hydrated with liquid water and steam at various conditions to reactivate the unreacted CaO. The hydrated samples were resulfated in a thermogravimetric analyzer for 90 min to evaluate the effect of hydration on the resulfation step. All four samples were significantly reactivated by steam hydration, which was much more effective than was hydration with liquid water, and the overall calcium utilization increased to 80-90% after reactivation, compared to 25-45% typical before reactivation. A scanning electron microscope was used to analyze Cadomin and Havelock samples, and both were uniformly sulfated before hydration. This work indicated that the uniformly sulfated samples could be reactivated given suitable hydration conditions.},
doi = {},
journal = {Energy and Fuels},
number = 6,
volume = 20,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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