Ash Benefits & Uses

South Africa only produces siliceous (pozzolanic) fly ash
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WHAT ASH IS AVAILABLE?

- Fly ash
- Classified fly ash
- Un-classified fly ash
- Clinker ash
   (old chain grate boilers)
- Cenospheres
   (limited availability)
- Bottom ash
- Disposed ash

South Africa produces in excess of 50 million tons of ash per annum with about a 10 % utilisation.

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WHAT ARE ITS BENEFITS?

In Concrete

- Increased post 28 day strength gain
- Reduced the rate of chloride diffusion through the concrete
- Prevents or retards alkali-silica reaction
- Reduced heat of hydration by up to 20 %
- Reduction of shrinking due to lower water demand
- Increase in overall durability of the concrete
- Improves sulphate resistance
- Improves the workability of fresh concrete
- Reduction in bleed water

Environmental

- Reduction of CO² emission
- Reduces disposal volumes and neutralises waste
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WHAT ARE ITS USES?

Typical uses of ash include:

- Cements and grouts
- Concrete Products & Bricks
- Ready mix concrete
- Artificial aggregates
- Road construction & soil stabilisation
- Soil conditioning
- Mine rehabilitation
- Agriculture
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