TY - JOUR
T1 - Influence of modern coal-fired power technologies on fly ash properties and its use in concrete
AU - McCarthy, Michael
AU - Yakub, Hamza I.
AU - Csetenyi, Laszlo
N1 - Acknowledgement is given to the Engineering and Physical Science Research Council (Doctoral Training Award) and UK Quality Ash Association and its members for funding the research described. The helpful technical input and suggestions by Drs Robert Carroll and Lindon Sear during the project are also greatly appreciated.
PY - 2019/10/1
Y1 - 2019/10/1
N2 - The work reported in this paper investigated the properties and use of fly ash (FA) produced from technologies developed to reduce the environmental impact and improve the efficiency of the coal-fired power generation process. These include nitrogen oxides (NO
x) reduction, co-combustion, supercritical steam technology and oxy-fuel combustion. The nine FA samples examined from these technologies were characterised physically, chemically and in terms of their reactivity. Tests were also carried out to determine the consistence (slump) and compressive strength of FA concretes. Comparisons were made with a selection of reference FAs, the requirements of BS EN 450-1 and reported FA studies from the 1980s and 1990s. The results indicated that, for some technologies, the FA tended to be coarser and of higher loss on ignition (co-combustion and in-combustion NO
x reduction) while, for others lower carbon contents were found (supercritical steam) or there was little obvious effect. FA chemistry was slightly affected in some cases, but mainly as expected for the coal being used. There was general agreement between water requirement and activity index with FA fineness for the materials tested. For the FA concretes, similar effects were noted in terms of the dosage of superplasticising admixture needed for a target slump and compressive strength. The behaviour of the materials from the new technologies was found to be similar to that reported in earlier studies on FA and suggests suitability for their use in concrete construction.
AB - The work reported in this paper investigated the properties and use of fly ash (FA) produced from technologies developed to reduce the environmental impact and improve the efficiency of the coal-fired power generation process. These include nitrogen oxides (NO
x) reduction, co-combustion, supercritical steam technology and oxy-fuel combustion. The nine FA samples examined from these technologies were characterised physically, chemically and in terms of their reactivity. Tests were also carried out to determine the consistence (slump) and compressive strength of FA concretes. Comparisons were made with a selection of reference FAs, the requirements of BS EN 450-1 and reported FA studies from the 1980s and 1990s. The results indicated that, for some technologies, the FA tended to be coarser and of higher loss on ignition (co-combustion and in-combustion NO
x reduction) while, for others lower carbon contents were found (supercritical steam) or there was little obvious effect. FA chemistry was slightly affected in some cases, but mainly as expected for the coal being used. There was general agreement between water requirement and activity index with FA fineness for the materials tested. For the FA concretes, similar effects were noted in terms of the dosage of superplasticising admixture needed for a target slump and compressive strength. The behaviour of the materials from the new technologies was found to be similar to that reported in earlier studies on FA and suggests suitability for their use in concrete construction.
KW - cement/cementitious materials
KW - chemical properties
KW - compressive strength
UR - http://www.scopus.com/inward/record.url?scp=85072912310&partnerID=8YFLogxK
U2 - 10.1680/jadcr.17.00208
DO - 10.1680/jadcr.17.00208
M3 - Article
SN - 0951-7197
VL - 31
SP - 435
EP - 447
JO - Advances in Cement Research
JF - Advances in Cement Research
IS - 10
ER -
