This SACCA webinar presentation explores the production and application of geopolymers derived from coal fly ash, a by-product of coal-fired power generation. Developed by researchers from institutions including the University of the Western Cape, the document highlights how industrial waste can be transformed into sustainable construction materials. The content covers the chemistry, processing methods, and performance of fly ash-based geopolymers, alongside real-world project results. With increasing pressure on industries like Eskom to manage waste and reduce emissions, geopolymers present a promising alternative to traditional cement, offering both environmental and economic benefits.

Key Insights / Summary

Key Topics Covered:

  • Coal fly ash contains key elements like silica and alumina, making it suitable for geopolymer production

  • Geopolymers are formed through chemical activation and curing processes, creating durable construction materials

  • Compressive strength of geopolymer products can reach up to 90 MPa, suitable for structural applications

  • Products include paving bricks, roof tiles, pipes, and concrete alternatives

  • Fly ash reuse helps reduce environmental pollution and landfill waste

  • Production can lower CO₂ emissions compared to traditional cement-based materials

  • Costs are competitive, with significant material savings due to high fly ash content (up to 73%)

  • Radiological considerations (e.g. radon emissions) must be assessed for safe use in buildings

Industry Relevance

  • Supports sustainable construction and green building initiatives

  • Provides a practical solution for managing coal ash waste from power plants

  • Reduces reliance on cement, lowering carbon emissions in infrastructure projects

  • Enables cost-effective production of building materials in developing markets

Related Resources

  • Industrial Relations in South Africa: Labour Law and Workplace Compliance

  • Coal Ash Management and Environmental Impact in South Africa

  • Sustainable Construction Materials: Alternatives to Cement and Concrete

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