Vedanta Aluminium, the largest aluminium producer in India, has announced the development of a groundbreaking process to significantly reduce the generation of bauxite residue, commonly known as red mud in the alumina refining process. The process reduces bauxite residue by a remarkable 30% by eliminating iron values while simultaneously recovering a higher alumina yield, reducing the total organic content from bauxite during the alumina refining. The process significantly enhances resource efficiency and curbs energy consumption during refining. The research project was led by the company’s Research & Development (R&D) department in collaboration with the Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur (IIT KGP), with special support from the Lanjigarh, Odisha unit, home to Vedanta’s world-class alumina refinery. This cutting-edge development will enhance the company’s operational excellence and have a sustainable impact on the global aluminium industry.
Bauxite is the primary ore for aluminium, and it undergoes an intermediate refining stage, known as the Bayer process, to produce alumina, which is then subjected to electrolysis to produce aluminium. This refining process generates bauxite residue as a by-product. To produce 1 kg of aluminium, it requires 2 kg of alumina, which consumes 6 kg of bauxite, leaving behind 4 kg of bauxite residue. Managing this voluminous by-product sustainably has been a long-standing industry challenge. Vedanta Aluminium is actively engaged in minimising bauxite residue and exploring avenues to extract value from it. The company has developed a revolutionary process, which has been successfully validated in the laboratory and patented. Presently, the company is focusing on establishing a pilot plant to implement and assess the process, along with determining its potential advantages.
On the breakthrough, Mr. GG Pal, Dy. CEO – Alumina Business, Vedanta Ltd., said, “At Vedanta Aluminium, operational efficiency is of paramount importance for us in achieving sustainability. Toward this goal, we are aggressively focusing on our in-house R&D initiatives to drive tech-led innovative solutions to address existing industry problems.”
Sharing his thoughts on the development, Dr. Amit Chatterjee, Chief Research & Development Officer, Aluminium Business, Vedanta Ltd., said, “We look forward to implementing our groundbreaking process in bauxite residue management in our refinery operations. This is a significant milestone that will offer a pathway to enhanced resource efficiency and energy conservation and contribute towards reshaping the global aluminium industry.”
Dr. Chenna Rao Borra, Assistant Professor, Department of Metallurgical and Materials Engineering, IIT Kharagpur said, “Vedanta Aluminium’s dedication to R&D for sustainability goals is truly inspiring. The reduction of bauxite residue has been one of the key challenges for the aluminium industry, requiring significant technological advancements. The process, developed through the collaborative efforts of IIT Kharagpur and the company, will not only significantly improve bauxite residue management but also contribute to reducing the carbon footprint in the process.”
Vedanta Aluminium is the first company in the country to extract the entire volume of water from bauxite residue slurry and recycle it back into operational use, achieving Zero Liquid Discharge (ZLD) and demonstrating its commitment to water conservation. The remaining bauxite residue is densely packed in dried form and stored in a specially constructed and scientifically managed concretized area called the Bauxite Residue Reservoir. This containment method prevents bauxite residue from inadvertently leaching into the groundwater. For this processing purpose, the company was the first in the country to establish a Bauxite Residue Processing Plant. With the new method implementation, this residue generation will be reduced further.
Additionally, Vedanta Aluminium is actively collaborating with research institutes to develop innovative technologies for the utilization of bauxite residue. These technologies include the beneficiation of bauxite residue to enrich Rare Earth Elements (REEs), the recovery of alumina and iron values, and processes for extracting and separating titanium and REEs like Scandium. This effort is crucial because bauxite residue houses valuable metals, including iron, alumina, REEs, and titanium dioxide.
Vedanta Aluminium, a business of Vedanta Limited, is India’s largest producer of aluminium, manufacturing more than half of India’s aluminium i.e., 2.29 million tonnes in FY23. It is a leader in value-added aluminium products that find critical applications in core industries. Vedanta Aluminium ranks 2nd in the Dow Jones Sustainability Index (DJSI) 2022 world rankings for aluminium industry, a reflection of its sustainable development practices. With its world-class aluminium smelters, alumina refinery and power plants in India, the company fulfils its mission of spurring emerging applications of aluminium as the ‘Metal of the Future’ for a greener tomorrow. www.vedantaaluminium.com
Indian Institute of Technology, Kharagpur is a higher educational and academic institute, known globally for nurturing industry-ready professionals for the world and is a pioneer institution to provide Excellence in Education, producing affordable technology innovations. Set up in 1951 in a detention camp as an Institute of National Importance, the Institute ranks among the top five institutes in India and is awarded, “The Institute of Eminence”, by the Govt. of India in 2019. The Institute is engaged in several international and national mission projects and ranks significantly in research output with about 19 academic departments, 12 schools, 18 centers (including 5 Centre of Excellence) and 2 academies with vast tree-laden campus, spreading over 2100 acres having 15,720+ students. Currently, it has about 810+ faculty, 880+ employees and 1270+ projects.