Vedanta Aluminium to Help Develop Low Carbon Cement Products
India’s largest producer of the aluminium and value-added products Vedanta Aluminium Business has invited partnerships from cement producers for using its by-products for manufacturing low carbon cement. The company expressed its interest for long-term collaboration with cement industry players on opportunities of using fly ash and bauxite residue in cement manufacturing, in a national workshop conducted with global industry experts. Fly ash and bauxite residue, the two most voluminous by-products generated by the aluminium industry, can be used in cement and concrete manufacturing, providing cement manufacturers significant benefits in terms of quality output, cost and sustainability.
Fly ash can partially replace cement in concrete (or be used to produce blended cement), significantly improving durability and workability of cement. With a 30-33% blending ratio, fly ash can help save 270 kg of carbon emissions for every tonne of cement produced. Bauxite residue can be added to the raw mix in clinker manufacturing to replace virgin bauxite, improving its hydraulic properties and strength. Owing to high concentration of iron oxide and alumina, bauxite residue is a better substitute for laterite, used in clinker manufacturing. Moreover, the residual caustic in bauxite residue helps in controlling the emission of sulphur when used directly, making it a better fit for the purpose. Both fly ash and bauxite residue being industrial wastes themselves come with significant cost and energy advantages as well.
Vedanta Aluminium supplied over 300,000 tonnes of fly ash to various cement plants in India in 2020-21. Since Feb’21, the company has also supplied over 30,000 tonnes of bauxite residue to cement manufacturers. The Business is additionally supplying fly ash free of cost to hundreds of local brick making MSMEs in its catchment.