This invention named RoyAl provides a way to form a composition for constructing road subgrades using by-products from alumina refineries. The composition comprises a mixture of bauxite residues (BRs), ordinary Portland cement (OPC), sodium silicate (SS), sodium hydroxide, and fly ash (FA), dispersed in water to form a thick slurry. The invention describes a methodology for constructing road subgrades with this composition, involving steps like surface preparation, mixture pouring, compaction, drying, and curing. This innovative method eliminates the need for pre-processing, making it more economical and efficient. The solution is eco-friendly, leveraging industrial by-products to create sustainable and durable road subgrades, contributing to the reduction of environmental pollution.
Figure (1) Patch of trials for subgrade construction executed in Hindalco’s Alumina plant
Bauxite residues (BRs) generated from the Bayer's process in alumina refineries present significant environmental and storage challenges due to their high alkalinity and substantial volume. These residues are often stockpiled at industrial sites, posing risks of soil, air, and groundwater pollution. The global annual production of BRs exceeds 120 million tons, with an accumulated quantity reaching up to 3 gigatons. Traditional disposal and management methods are not sustainable, economical, or environmentally friendly.
- No pre-processing required: Eliminates steps like drying, crushing, or sintering, making the process more time-efficient and cost-effective.
- Direct bulk utilization of BRs: Facilitates the immediate use of Bauxite Residues, reducing storage and disposal issues.
- Environmentally friendly: Reduces the ecological impact of industrial waste, promoting sustainable practices.
- Cost-effective and economical: Lowers overall costs by utilizing waste materials and minimizing processing requirements.
- Enhanced road construction quality: Provides a durable and reliable subgrade material, improving the longevity and performance of road infrastructure.
Two pilot scale demonstration were done in HINDALCo Alumina plant at Utkal(UAIL) and Vedanta Lanjigarh. A subgrade construction was undertaken as per the process recommended in the Patent. The trial patch of subgrade was tested for load bearing by light automobiles and lab test were performed to estimate California Bearing Ratio (CBR) for subgrade strength measurement. The trial patch had a CBR value of 11.6% and 12.3% for 180 mm and 600 mm thickness respectively. This proved the strength of the subgrade to be at par with the current available alternatives. The trial patch was also tested for a leaching test to address environmental concerns. The leaching test also confirmed the lab results and were found to be satisfactory as per environmental requirements. This establishes that the patented resolution is an environmentally friendly high performing methodology.
The technology is ready to be deployed without any further modifications. The results from both the field trials have been evaluated and found to be confirming the lab results, thereby extending the confidence in full-scale deployment.
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This strategy helps reduce environmental pollution and the ecological footprint of alumina refineries by converting hazardous waste into valuable construction material. This not only lowers waste management costs but also enhances road construction practices by offering a cost-effective and durable subgrade material.
- Road construction
- Pavement construction
- Embankment construction
Geography of IP
Type of IP
201921014911
410479