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

Large concrete beam prototypes have been created using both fly ash and pond ash and shown to meet Australian Standards for engineering performance and environmental requirements.

From Science Daily • May 15, 2024

Shortly before 9 a.m. local time, the three plant employees were working on unplugging the facility’s western silo which contains fly ash, a type of coal ash and a byproduct from creating power.

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

A worldwide spike in fly ash from burning coal also occurs in 1950.

From Los Angeles Times • Sep. 3, 2023

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

From "Meltdown" by Deirdre Langeland