Fluidized Bed Combustion (FBC) Fly Ash and Its Performance in Concrete

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Fluidized Bed Combustion (FBC) Fly Ash and Its Performance in Concrete

Author(s): Mona Zahedi and Farshad Rajabipour

Publication: Materials Journal

Volume: 116

Issue: 4

Appears on pages(s): 163-172

Keywords: anthracite coal; ASTM C618; benefication; bituminous coal; fluidized bed combustion; fly ash

Date: 7/1/2019

Abstract:
Concerns over the availability and quality of conventional fly ash for use in concrete has become widespread in recent years. Fluidized bed combustion (FBC) ash, with its annual U.S. production exceeding 14 million tons, could serve as a reasonable alternative. In this study, two compositionally different fly ashes from circulating FBC (CFBC) power plants were evaluated for their compliance with the ASTM C618 standard and their impact on the fresh and hardened properties of concrete. The pozzolanic reactivity of the fly ashes was also quantified based on the emerging RILEM test method. These fly ashes met the chemical and physical requirements of ASTM, except for elevated LOI (in both fly ashes) and elevated SO3 (in one fly ash). Despite this, concrete with proper slump, air content, and strength development could be produced by proper dosing of chemical admixtures. The elevated SO3 was found not to produce deleterious expansions.