[ COVER STORY ]
Tenova offers a full range of burners that operate seamlessly between natural gas and hydrogen .
inject smaller amounts of DRI into the hot liquid , ensuring a more efficient melting process .”
Tenova has also tackled the challenge of homogenizing the liquid steel bath within the large vessel . In collaboration with ABB , they introduced the Consteerer ®, a magnetic induction system that continuously stirs the molten steel inside the furnace .
The size and capacity of modern EAFs also pose greater challenges to the electrical grid . While continuous charging of the furnace can reduce disturbances to the grid , with the size of the EAF increased additional equipment must be added , such as Statcom systems . “ As a further improvement we are now
fundamentally changing how we connect the grid to the furnace and supply energy , proposing a system by General Electric called Direct Feed , which uses a high-voltage inverter instead of a transformer . This drastically reduces disturbances sent back to the grid , which is essential . If we do not meet the limits set for grid connections , we cannot install the furnace . Our innovations enable us to stay within these limits ,” Mr . Pancaldi remarked . “ Overall , this represents a completely different machine from what existed years ago , much more sophisticated and digitally controlled .”
From gas to green
In the downstream portion of its business , Tenova is actively contributing to emissions reduction by decarbonizing heat generation . “ CO 2 is produced downstream mainly because steel must be heated multiple times , often to very high temperatures , around 1100 – 1200 degrees Celsius . Traditionally , gas-fired burners have been used for this stage ,” stated Mr . Pancaldi .
To address this challenge , Tenova has transitioned from conventional burners to recuperative and regenerative burners , which recycle the heat lost by the system to preheat the incoming gas or air . This process has been enhanced through improved combustion control using digital tools .
“ We are also striving to electrify heat generation as much
10 Green Steel World | Issue 15 | November 2024