Abstract
The pollution caused by the wastes of semi-dry and dry flue gas desulphurisation (FGD) processes and the increasing cost of disposal make their utilisation imperative. The paper presents the first part of a comprehensive investigation to optimise the use of FGD wastes in concrete manufacture. Batches of FGD materials from actual industrial disposal sites and laboratory simulations based on fly ash and gypsum were investigated, representing the following categories: non-siliceous and deleteriously reactive; non-siliceous and non-reactive; siliceous and pozzolanic active. Generic relationships were derived that emphasise the importance ofSO3 content on concrete properties. There is an exponential relationship between strength and SO3 content and also between strength and SiO2+Al2O3. The results show that SiO2–Al2O3–CaSO4- basedFGDwastes withSO3<15% retard early strength but increase long-term strength. Mortars containing fly ash–gypsum (FA–G) blend (25% replacement) with gypsum contents up to 35% (SO3 content up to 18·37%) do not suffer long-term strength reduction. An optimum FA–G blend has an SO3 content less than 10%. Author(s): P.S. Mangat 1 , | J. M. Khatib 2 , | L. Wright 3Citation
Construction Materials, 159(3): 119-127Publisher
Thomas TelfordAdditional Links
http://www.atypon-link.com/TELF/doi/abs/10.1680/coma.2006.159.3.119Type
Journal articleLanguage
enDescription
Metadata onlyISSN
1747650X17476518
ae974a485f413a2113503eed53cd6c53
10.1680/coma.2006.159.3.119