Key Takeaways
- CSIR develops technology to convert hazardous foundry sand into eco-friendly bricks
- New unit to produce 5,000 bricks daily using 30 tonnes of waste sand
- Solution addresses India’s 3 million tonnes annual foundry waste problem
India’s hazardous foundry sand waste will now be transformed into eco-friendly construction materials through innovative technology developed by the Council for Scientific and Industrial Research (CSIR). This breakthrough addresses a major environmental challenge while creating cost-effective building solutions.
Scale of the Foundry Waste Problem
India’s foundry industry, the world’s second largest after China, generates approximately 3 million tonnes of waste sand annually. This toxic byproduct contains heavy metals and poses serious environmental threats including land contamination, water pollution, and air quality degradation through dust particles.
The problem is particularly acute for small and medium-sized foundries, which constitute over 85% of India’s approximately 5,000 foundry units. These enterprises often lack resources for proper waste treatment, leading to improper disposal practices.
CSIR’s Technological Breakthrough
CSIR’s National Institute for Interdisciplinary Science and Technology (NIIST) has partnered with private industry to establish a production unit that will manufacture around 5,000 bricks per day. The facility will consume approximately 30 tonnes of waste sand daily.
“NIIST has systematically studied the reactivity of the foundry sand waste with cement, lime, gypsum, and polymer modified binders and documented the critical parameters such as strength, density, water absorption properties usually required for building bricks,” a CSIR statement said.
“The continued scientific studies resulted in a process for making bricks through a simple cement bonded compression moulding technique,” the statement added.
Product Specifications and Applications
The manufactured bricks comply with IS-1077 standards for common burnt clay building bricks and offer several advantages:
- Completely avoids using natural raw materials like clay, sand, and gravel
- Available in aesthetically appealing colors for architectural applications
- Suitable for paving tiles, hard aggregates, and interlocks
The technology represents a significant step toward sustainable waste management in India’s vital foundry industry, which employs approximately 500,000 people directly and indirectly.



