SBIR Phase I: Using Geopolymerisation of Natural Aluminosilicate Minerals to Develop Sustainable Masonry Materials

This Small Business Innovation Research Phase I project aims to manufacture a masonry building block from materials that could radically improve the environmental profile of one of the most common construction products on the planet. The research will investigate the feasibility of using engineered alkali-activated soil blends to promote geopolymerisation in the presence of nanoaluminosilicates using a novel manufacturing process. The specific fine particle components, specifically clay minerals, micas and feldspars, are commonly found in soil and recycled materials from commercial aggregate and quarrying operations. The intellectual merits of the project include a deeper understanding of geopolymerisation in the presence of nanoaluminosilicates, the measurement of the structural capabilities of engineered soil blends composed of these materials under extreme compaction, and the ability to utilize a wide range of natural soil sources to produce durable, structurally-stable masonry products. The anticipated result is an environmentally-sustainable stabilized earth building block, with equivalent performance to traditional concrete blocks, but with a reduction in embodied energy by as much as 90% due to the total elimination of energy-intensive Portland cement binders. The broader impact/commercial potential of this project is the potential to transform traditional cement-based masonry products on a global scale. The product will meet a clear market need for sustainable materials in both the US and global construction marketplace. The elimination of traditional ordinary Portland cement (OPC) in masonry blocks will provide valuable social and environmental benefits to the public in the form of reduced carbon dioxide (CO2) emissions, increased economic activity, and improved public health. Approximately 8 billion concrete blocks are manufactured in the US annually to support construction activities, requiring the use of 15 million metric tons (MMT) of OPC. The manufacture of this cement emits approximately 14 MMT of CO2, which represents 0.25% of the 6,000 MMT of industrial CO2 emissions overall in the US. The use of soil, a ubiquitous, innocuous and unlimited resource, as the principal component of stabilized earth mix designs, promises the possibility of sustainable cradle-to-cradle environmental performance over a full product life cycle. From an economic perspective, green construction, which is projected to reach $96-140 billion by 2014, is the fastest growing segment of the construction market, which itself is a key driver of the national economy.