Partial replacement of cement by lignite fluid combustion ash and its impact on concrete sulphate resistance

conference paper

English

This paper presents findings concerning testing of concrete with partial cement replacement by fluid combustion ashes as to sulphate resistance. Concrete samples have been exposed to aggressive media for a period of 18 months. Secondary raw material exploitation for building material, among others, also for concrete production is a long-time trend. Fly ash is one of waste originating in heat and power plants with coal combustion. More and more combustion plants switch to combustion in floatation i.e. fluid combustion. Such combustion produces ashes of chemistry diametrically different from classic combustion ones. Ash originates with dust coal combustion in heat and power plants. Ash in flue gas is trapped in dust settling chambers in their mechanical or electrostatic separators. All mineralogical components are exposed to high temperature for various time periods during combustion, and - moreover - they can pass through oxidizing/reducing environment. Ashes contain always residues of original solid fuel or, as the case may be, residues of metamorphosed fuel.

concrete, cement, fluid ash

BROŽOVSKÝ, J.; MARTINEC, P.

1. 1. 2004

VUT V Brně

Brno

25

29

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