What is Fly Ash?

Fly ash is a fine, powdery byproduct generated from the combustion of pulverized coal in thermal power plants. It primarily consists of silica, alumina, and iron oxides, with its composition varying based on the type of coal burned. Fly ash particles are typically spherical and range in size from 1 to 100 microns.

Fly ash is collected from flue gases by electrostatic precipitators or filter bags before the gases are released into the atmosphere, making it an important material for reducing environmental pollution.

Due to its pozzolanic properties, fly ash reacts chemically with calcium hydroxide in the presence of water to form compounds that contribute to the strength and durability of concrete. This makes it a valuable supplementary cementitious material widely used in construction to enhance the performance and sustainability of concrete.

Using fly ash in concrete improves workability, reduces permeability, and increases resistance to chemical attack, while also lowering the heat of hydration. Additionally, incorporating fly ash helps reduce cement consumption, which decreases carbon dioxide emissions associated with cement production.

Fly ash is also utilized in road construction, soil stabilization, and as a filler in various industrial products.

While fly ash is generally safe to handle, inhalation of fine particles can irritate the respiratory system, so protective measures such as masks and proper ventilation are recommended during handling and transport.

USES AND APPLICATIONS

INDUSTRIES

Fly ash is commonly used in:

• Cement and concrete manufacturing as a pozzolanic additive
• Road and infrastructure construction
• Soil stabilization and reclamation projects
• Manufacturing of lightweight aggregates and bricks
• Waste management and environmental remediation