Daniel Burton on shifting to electric heating systems for more eco-friendly production
The green revolution is accelerating in many industries, as next-generation electric heating systems gradually replace gas burners. But how can a furnace help achieve a business’s sustainability goals?
In aluminium production, for instance, each process presents a specific set of challenges, and heat is the ingredient that solves many of these potential issues. For example, anodes are large carbon blocks that conduct electricity during the aluminium reduction process. Due to the porous nature of their material, anodes accumulate humidity, which can result in explosion or a connection failure upon becoming energised. As a result, the anodes must undergo preheating to dry them out.
At an anode preheating station, a critical part of the process is to raise the temperature of the anode slot to above 100°C in less than one minute, before pouring molten iron into the slot. Extreme heat requires extreme power and, because of this, furnaces play a vital role in fuelling aluminium production.
Cut the cost
However, all of this heat comes at a price. Most commonly, the furnaces that deliver the temperatures needed for aluminium production are powered by fossil fuels. Although fossil fuels are effective, their negative impact on the environment is no secret. Yet demand for aluminium is rising.
While we continue to rely on aluminium, much of this increase in demand is actually part of efforts to reduce emissions. For example, aluminium cars are lighter than those made from steel, which helps to reduce fuel consumption. Aluminium is also easy to recycle, which reinforces its potential as a green resource.
To support this potential, and also to further it, aluminium production must undergo some environmental improvements. One is to switch from fossil fuels to electric-powered furnaces.
Electric heating systems by Kanthal– part of Sandvik Group – are designed for a range of industrial heating applications, including aluminium and steel processing. They are shown to deliver reductions in energy consumption compared with gas-heated systems. In fact, the net efficiency of these electric heating systems is 70%, compared with only 20% for gas. Electric furnaces can also help achieve a cleaner, safer and quieter working environment, making it a much healthier place for employees.
Aluminium production has changed little since the 1800s, when the smelting process was initially pioneered. Because of this, although electric furnaces demonstrate “a new dawn” of sorts for aluminium, the material’s long and unchanged history makes it difficult to realise new innovations.
To help its customers begin the process of switching from fossil fuels to electric-powered furnaces, and to help them reach their own sustainability targets, Kanthal has developed a service portfolio that includes a customised, onsite evaluation service. The service provides calculation models, reports and recommendations to help identify the best electric furnace for each customer’s specific needs.
The services are helping to deliver a measurable and lasting environmental impact for Sandvik, its customers and the planet. This is backed-up by data from measuring 34 installations of Kanthal electric furnaces across the globe. The firm tracks a running total of the CO2 savings that these furnaces have achieved. The total, which updates every second, has counted hundreds of millions of kilograms, so far.
Creative collaboration and identifying the need for change are key to breaking age-old traditions, which include those relating to sustainability and aluminium production. Although it’s clear that we need to change our approaches to industrial heating, executing these changes isn’t always easy.
That’s why, by implementing a progressive evaluation process, Kanthal and Sandvik have demonstrated that a simple switch can deliver considerable progress. Using electric heating for processes such as anode preheating, the right equipment can contribute towards reducing CO2 emissions, even in unlikely applications.
Daniel Burton is with Kanthal, part of Sandvik Group