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

In fact, the heaps of fly ash waste produced by coal-processing power plants are often just as — if not more radioactive — than nuclear waste sites.

From Salon • Jun. 2, 2024

Although Dr. Siddiqua doesn't foresee a huge uptick in rammed earth homes and buildings sprouting up in the short term, the addition of materials like fly ash into composite cements has already begun.

From Science Daily • Feb. 23, 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

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