Track 2: Materials over Time: Points of Change
Alkali Activated Bricks: Building a Path to a Greener India
Tuesday, September 25
8:30 AM - 10:00 AM
Location: BNCC- 101BG
India is home to over 1.35 billion people, making it the second most populous nation in the world, with studies predicting it will surpass China for the largest population by 2030. This spike in population leads to an inevitable increase in the demand for buildings and infrastructure. Historically, the clay fired brick is the most commonly used building material in India due to its low manufacturing cost and the availability of clay throughout the country. Despite the clay fired brick’s long standing dominance as the building material of choice for housing, a number of environmental concerns surrounding its production have raised concern about its future use, making the demand for more sustainable building materials a pressing issue in India.
In parallel with the growing population, India is experiencing rapid industrialization and generating vast quantities of industrial wastes and byproducts such as carbon dioxide. While some of these wastes are being recycled, the majority are land-filled or disposed of illegally, posing serious hazards to both the environment and human health.
In this presentation, you will learn how a multidisciplinary team of professors, postdocs, and students from MIT are addressing one challenge, namely working to sustainably meet the unprecedented need for building materials stemming from population growth, by leveraging another, the production of vast quantities of waste from industrial activity. Their continuing research aims to utilize industrial ash byproducts as a raw material in the production of affordable and sustainable bricks that can be used for new construction and restoration of existing structures.
The technological strategy employed in creating these bricks is alkali-activation, a method that depends on a chemical reaction between amorphous alumina and silica rich solids and an alkaline activator. This strategy uses a low energy curing process allowing the bricks to gain strength at ambient temperature.
The industrial byproduct utilized in the research is boiler ash, a waste produced at small to medium sized factories that generate their own energy by burning a variety of raw materials. The continuous change in the quantity and quality of raw material sources produce ash with a high variability in its physical and chemical properties, thus far creating a barrier to finding a beneficial use for this waste.
This presentation will highlight the team’s findings over the past five years of research and discuss the next steps that are being carried out for these bricks to be implemented. While this presentation is atypical for APT, the hope is that it will garner interest and further research and development in sustainable building materials in India and other third world countries.
- Understand how significant population growth and rapid industrialization in India are driving the demand for building and infrastructure, creating a need for more sustainable building materials.
- List the differences in the mineralogical and micro-structural properties of boiler ash and fly ash as it relates to their use in alkali activated materials.
- Compare the properties of alkali activated bricks and traditional clay fired bricks as measured by their technical, environmental, and economical performance.
- Recognize the importance of research and development into affordable and sustainable materials in the developing world.