Environmental Implications of Quarry Rock Dust: A Sustainable Alternative Material to Sand in Concrete

Sand is a vital natural resource of our ecosystem, yet the construction industry is threatening its availability. Excessive mining of sand imposes adverse effects on our environment, and this problem is becoming extremely severe as it is exposing the river ecosystem and endangering marine biodiversity across the world (i.e., Tamil Nadu in India, Poyang in China, and California in the United States). Quarry rock dust (QRD), a waste obtained during the quarrying process is a significant source of air pollution yet has the potential of becoming a sustainable and economical alternative to sand in concrete. Studies confirmed that replacing sand in conventional concrete with QRD increases its durability and robustness by ten percent. The objective of this study is to determine QRD's environmental implications through carbon footprint analysis. To achieve this, the research utilizes one of the very few case studies of Barbados Quarry site that produces more than 35,000 tons of aggregates per month and 500,000 tons of QRD is produced as a by-product. This research prepares a preliminary life cycle analysis of QRD, its carbon dioxide emissions as well as the economical analysis of QRD. The findings of this study promote the use of QRD considering its less environmental impact in comparison to sand when used in concrete. The study also encourages a paradigm shift in concrete practices, which not only paves for a more resilient alternative to concrete but also a more sustainable construction process.