In the heart of Ghana, a groundbreaking study led by Michael Commeh at the Technology Consultancy Centre – International Center for Innovation, Manufacturing, Technology Transfer and Entrepreneurship (UNESCO c2c for Engineering Education in Africa) at Kwame Nkrumah University of Science and Technology is turning agricultural waste into a goldmine for the construction industry. The research, published in ‘Discover Civil Engineering’ (translated to English as Discover Civil Engineering), focuses on transforming rice husk waste into valuable biochar and pozzolanic ashes, offering a sustainable alternative to traditional cementitious materials.
Rice husk, a byproduct of rice milling, is typically discarded, contributing to environmental pollution. However, Commeh’s team has developed a novel approach to convert this waste into rice husk ash (RHA) and biochar using a locally built pyrolysis system. This process not only reduces waste but also enhances the pozzolanic properties of the materials, making them suitable for use in cementitious blends.
The study delves into the chemical composition and mechanical performance of these new materials. By replacing Ordinary Portland Cement (OPC) with varying percentages of RHA and biochar, the team conducted compressive strength tests on mortar mixes. The results were promising: a 10% replacement of RHA showed the highest strength at 12.1 N/mm2, while other mixes, except for the control and 15% biochar, demonstrated improved strength over the control.
“Utilizing rice husk ash in cementitious materials not only encourages efficient circular economy principles but also promotes environmentally sustainable infrastructure,” Commeh emphasized. This research underscores the potential of bio-renewable resources in construction, paving the way for sustainable development and the transition of agro-waste cementitious mixes from small-scale trials to industrialized production.
The implications of this research are vast. By reducing the reliance on OPC, a significant contributor to CO2 emissions, the construction industry can take a substantial step towards sustainability. The locally built pyrolysis system used in the study offers a scalable solution that can be adopted globally, transforming agricultural waste into valuable construction materials.
As the world grapples with climate change and resource depletion, Commeh’s work offers a beacon of hope. It demonstrates how innovative thinking and technological advancements can turn waste into wealth, creating a more sustainable future for the construction industry and beyond. This research is a testament to the power of circular economy principles and the potential of bio-renewable resources in shaping the future of construction.