fly ash

American  

noun

1. fine particles of ash of a solid fuel carried out of the flue of a furnace with the waste gases produced during combustion.

2. such ash recovered from the waste gases, used chiefly as a reinforcing agent in the manufacture of bricks, concrete, etc.

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fly ash British  

noun

1. fine solid particles of ash carried into the air during combustion, esp the combustion of pulverized fuel in power stations

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Etymology

Origin of fly ash

First recorded in 1930–35

Example Sentences

Better described as a fine powder, fly ash shares the same strength and texture characteristics as cement, which is often added to concrete to enhance its strength.

From Science Daily • Feb. 23, 2024

Plant staff also isolated the affected part of the silo and shut off any further leakage of the fly ash.

From Washington Times • Dec. 20, 2023

The larger, so-called coarse particles, have diameters between 2.5 and 10 micrometers; some examples of this type of particulate matter include wind-blown dust, fly ash and animal or vegetal particles.

From Salon • Nov. 30, 2023

To mitigate the use of concrete, which is carbon-intensive, the team developed a formula that contained a higher percentage of fly ash, making it more sustainable.

From Los Angeles Times • Sep. 19, 2023

They become concentrated in fly ash, some of which escapes through the chimneys of coal-burning plants.

From "Meltdown" by Deirdre Langeland