Heating without gas : The green revolution


The green revolution is accelerating in many industries, as next-generation electric heating systems gradually replace gas burners.

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 degrees Celsius 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. While 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 ones 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 are designed for a range of industrial heating applications, including aluminium and steel processing. They are shown to deliver significant reductions in energy consumption compared with gas-heated systems. In fact, the net efficiency of Kanthal electric heating systems is 70 per cent, compared with only 20 per cent for gas.

Electric furnaces can also help achieve a cleaner, safer and quieter working environment, making it a much healthier place for employees.

Go green

Aluminium production has changed little since the 1800s, when the smelting process was initially pioneered. Because of this, while 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. Kanthal 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.

Winning results

To recognise the success of Kanthal’s sustainable innovation, Kanthal Services was nominated for the first Sandvik Sustainability Award in Memory of Sigrid Göransson, named in honour of the famous Swedish philanthropist (1872-1963) who was born, and died, in Sandviken, Sweden, the town where the Sandvik company was founded.

Award entries came from all three of Sandvik Group’s business units — Sandvik Materials Technology, Sandvik Rock and Mining Technology, and Sandvik Machining Solutions — all of which have made considerable progress towards the group’s sustainability goals. These objectives include halving Sandvik Group’s CO2 impact by 2030, towards which Kanthal Services significant contribution saw it crowned as the winner of this year’s award.

In addition to aiding Sandvik’s goals, Kanthal’s evaluation has helped its customers meet their own sustainability and workplace targets, comply with regional emissions rules, and has even facilitated support from the Government of Sweden for expansion projects.

Creative collaboration and identifying the need for change are key to breaking age-old traditions, which include those relating to sustainability and aluminium production. While it’s clear that we need to change our approaches to industrial heating, executing these changes isn’t always easy.

Article by —
Daniel Burton,

Daniel Burton is Business Manager at Kanthal, a part of the Sandvik Group