Coal fly ash is a compound blend of anthropogenic materials formed during the combustion of pulverized coal in coal-fired power plants. They carry environmental concerns that lead to air and water pollution. The efforts have been done for reducing the production of coal fly. Cenospheres are light, low density, thin-walled hollow ceramic microsphere with distinctive properties. Conventional cenosphere production procedures involve the separation of cenospheres from coal fly ash. Fine fractions of non-magnetic cenospheres comprise 2.6–3.5 wt % Fe2O3 and embrace globules with an even smooth surface and shells with different degrees of absorbency. The aluminum absorption rise leads to an increase in the mullite phase content and a decrease in the average sphere diameter, shell thickness and porosity, glass-crystalline, and the crystalline quartz content.
The advantages of Cenospheres:
- Spherical shape
- Free flowing
- High-melting point
- Electrical properties
- Low oil absorption
- Good packaging factors
- Versatile filler with applications in an extensive range of products for both commercial and industrial use.
However, in each case, Fillite is used for its unique properties, such as strength, low density, and chemical resistance. Fillite can be used for the applications in Cement, Latex emulsions, Polyurethane, PVC, Epoxy Resins, and Unsaturated Polyester Resins.
- Cenospheres are made up of silica, iron, and alumina.
- They have a size ranging from 1 to 500 microns with a usual compressive strength of 3000+ psi.
- Colors range from white to dark gray.
- They are chemically inert & are reclaimable and labeled as environmentally sound.
- They are formed during the molten state of ash and attain spherical shape to have minimum surface tension.
The residue from coal after combustion has been a challenge for Indian power sector, which is dominated by coal. Presently the country produces approximately 160 million tons of fly ash, of which merely 80 million tones is being utilized. Improvements in the durability and strength of manufacturers’ end products and a reduction in product weight enhance marketing strategies are required. Manufacturers are dedicated in producing quality chemical and physical product on a consistent basis is critical for the end use customer.