Conference Agenda

Molten metal safety in many smelters is an afterthought. This mistake comes back to haunt them later when molten metal incidents occur in the potlines, casthouses, and rodshops. Not only are production stoppages commonplace but workers are being injured and killed. There is a gap in literature detailing molten iron and aluminium safety in a smelter. This paper will explain why explosions occur with aluminum as well as iron. This paper will review specific molten metal incidents and explain how they could have been prevented. Common reasons for molten metal explosions in smelters will be discussed. Failure to consider both molten iron and molten aluminium safety in smelter not only endangers workers but the smelter as a whole.

Over the past decade, annual bauxite exports from Guinea have increased from 18.5 million tonnes (dry) in 2013 to 111 million tonnes (dry) in 2023, representing a compound annual growth rate (CAGR) of approximately 20 %. Almost all of the additional tonnes mined and exported from Guinea over the ten-year period have been destined for China, despite the enormous geographic distance between the two countries. Guinean bauxite is characterized by its high gibbsite content and low reactive silica content, which makes it highly desirable for alumina production, typically using low-temperature (LT) Bayer processing. Chinese domestic bauxite is characterized by its high diaspore content and high silica content, which requires high-temperature (HT) Bayer processing. This paper seeks to explore the drivers behind China’s voracious appetite for imported bauxite, its ability to adapt existing refining capacity from HT to LT Bayer processing and how Guinea has managed to position itself as the country of choice for Chinese bauxite importers.

The objective of this paper is to explain the transformation of the Aluminium Bahrain (Alba) safety culture during the period of 2007-2019. I joined Alba as General Manager of Finance in 2007 and completed my career as CEO at the end of 2019. During my time at Alba I also held the roles of Chief Financial Officer, Chief Marketing Officer and Chief Supply Chain Officer.

Alba is one of the largest industrial companies in the Middle East and was the first primary aluminium smelter in the region. Alba is the largest smelter outside China with an annual production of 1.6 Mt per annum. Alba is a huge contributor to the Bahrain economy with the Alba and the whole aluminium industry representing approximatively 12 % of the GDP of the country.

Today Alba is considered a world leader in safety, winning many accolades for its safety performance and the continued goal to achieve zero injuries. However, this was not always the case and there was a period of time when Alba had poor safety performance. When I joined Alba in 2007, I would describe the safety culture as one of compliance where there were many policies and procedures, but it was a just “Check the box” exercise.

Anyone who has worked in an aluminium smelter knows that there are significant inherent risks in the operation. There is dealing with the electrical hazard risks in the potline areas as well as the movement of liquid metal at 965 ºC, large hot furnaces as well as many vehicles and cranes in constant motion around the plant. Given the nature of these risks it is critical that the company have a strong safety culture. Sadly, safety was not the number one priority when I joined Alba and the focus was on production targets. The prevailing attitude toward safety was it is not my job, that is the job of the Safety Manager.

Hindalco, a flagship company of Aditya Birla Group, began its journey in 1958 from Renukoot, Uttar Pradesh state of India, as a first integrated plant of Independent India. Renukoot plant received bauxites from Lohardaga mines and hydropower from G B Pant Sagar Dam project to produce 40 ktpa alumina refinery and 20 ktpa aluminium smelter. Over the years, through successive organic expansions the company reached to 242 ktpa by 1999. This was followed by expansion through acquisition of INDAL and Novelis, a biggest expansion by an Indian company to become the largest Flat Rolled Products (FRP) producer in the world. In the last two decades, Hindalco continued its expansion by adding Utkal alumina refinery and new state of the art AP36 smelters at Mahan and Aditya.

During this journey, a range of technologies were adopted to achieve the best technical and financial performance. For alumina extraction from Boehmitic bauxite of Lohardaga, the company mastered double digestion technology. We were first in world to test the Gas Suspension Calciner technology of FLSmidth and commissioned a plant in 1986 replacing the rotary kiln technology for production of smelter grade alumina. Many technical initiatives and strategic collaborations helped Utkal alumina refinery to become one of the lowest cost producers of alumina.

The best plant practices and technical inquisitiveness helped us to develop and implement in-house technologies like copper insert collector bars, magnetic compensation loop, energy efficient cell lining designs, etc. for both old and new smelters. These technology developments helped to not only reduce specific energy consumption but also achieve high quality metal with special LME grading, including best quality P0202 grade metal from Mahan smelter.

The technological partnership of our downstream plants with Novelis and Aleris has realised a range of new products and applications. We are leading the lightweighting of mobility sector in India by introducing aluminium bulkers, trailers, railway wagons and range of products for Electric Vehicles (EV) like battery foils, separators and enclosures.

As a responsible producer, we have a special focus on sustainability with a target of net zero in emission, discharge and land fill by 2050. Various technology initiatives from generation and storages of renewable energy, 100 % utilisation of bauxite residue, decarbonisation technologies areas assisted company to rank number 1 in Dow Jones Sustainability World Index, consecutively for the last 3 years. Adoption of Industry 4.0 driven digital technology transformations in various areas of aluminium value chain and customer centricity, is also facilitating to achieve these challenging targets.

In the past 20 years, the Chinese primary aluminum industry faced new challenges, such as the stricter standards for both carbon emission and energy-saving, the impoverishment of bauxite resources, the deterioration of petroleum coke quality, the complexity of the spatial and temporal distribution characteristics of high/ultra-high amperage cells, and the shortage of labor resources. Therefore, the technical teams of Chinese aluminum industry, represented by experts from Aluminum Corporation of China and Central South University, developed a complete set of energy-saving, low-carbon and digital, intelligent aluminum electrolysis technology. This was a major breakthrough in energy conservation and carbon reduction, and played a key role in maintaining the global leading position of energy consumption indicators for Chinese aluminum industry. A new method for online monitoring and regulation of the spatial and temporal distribution characteristics of high/ultra-high amperage aluminum electrolysis cells was proposed, and the key technology of intelligent optimization and manufacturing of aluminum electrolysis was developed. This technology is based on distributed monitoring and digital twin, resulting in "the digital intelligence of distribution parameters" for the control of aluminum electrolysis process, which opened new opportunities for energy saving, carbon emission reduction, and process efficiency improvement. The combination of innovative cathode design, and multi-field optimization improved magnetohydrodynamic stability of the cells. Energy saving technology, based on steady flow and heat preservation, was developed, which enabled the cell voltage reduction for a further energy saving in varying cell operation environment and production conditions of Chinese aluminum industry. The production and application of dust-free prebaked anodes solved technical problems caused by the quality deterioration of both anodes and alumina.

The application of these technologies reduced cathode voltage drop by about 150 mV, increased the current efficiency by 0.5~1.5 %, reduced the amount of carbon dust by half, increased the labor productivity by more than 30 %, and reduced energy consumption by 200 to 600 kWh/t Al. In 2023, the average overall AC power consumption of Chinese primary aluminum was 13324 kWh/t Al, a decrease of 2155 kWh/t Al compared with that of 20 years ago, which is absolutely a tremendous improvement in energy conservation and emission reduction.

Panel discussion following the presentations