UTILIZING POWER PLANT WASTE FOR SUSTAINABLE BUILDING MATERIALS: ADVANCING NIGERIA’S CIRCULAR ECONOMY

Abstract

Power plant waste, including fly ash, slag, bottom ash, and flue gas desulfurization (FGD) gypsum, offers a sustainable solution to address environmental, economic, and resource challenges in construction. This study explores the potential of these byproducts to replace conventional materials in Nigeria’s construction industry, aligning with global sustainability trends. Comprehensive characterization revealed their compatibility with pozzolanic and cementitious applications, meeting chemical and physical requirements. Concrete with fly ash replacement up to 20% achieved comparable compressive strength (32.1 MPa at 28 days) to conventional cement, with enhanced durability through reduced water absorption (6.9%) and minimal freeze-thaw weight loss (1.1%). Life-cycle analysis demonstrated substantial environmental benefits, including reductions in greenhouse gas emissions (up to 28%) and energy consumption (up to 25%). Economic analysis showed cost savings ranging from 11% to 23% at optimal replacement levels. Despite these advantages, challenges such as variability in material properties and inadequate infrastructure highlight the need for standardized preprocessing methods and regulatory support. Recommendations include establishing regulatory frameworks, incentivizing recycling, and investing in infrastructure to enable scalability. The findings emphasize the transformative potential of power plant waste in advancing sustainable construction practices, reducing environmental footprints, and promoting resource efficiency in developing nations. Future research should focus on optimizing higher replacement levels, assessing long-term performance, and evaluating socio-economic impacts to facilitate widespread adoption.