The Nippon Gases offices in Madrid hosted the 4th General Assembly of the Twinghy project in October 2024.

The project started in 2023, and will continue for three years. The project has a total budget of over EUR 8 million and has nine participating companies or organizations. Half of the total budget is funded  by the EU and the rest by the participating companies and organizations.

The objective of the project is to explore the use of hydrogen as a viable alternative to traditional natural gas combustion in reheating furnaces in the steel sector. By developing a digital twin, a virtual copy of the physical system, the project aims to simulate and optimize the hydrogen combustion process. By combining simulation and experimentation, the project aims to provide a deeper understanding of how the technology performs, safety aspects and environmental impact, to facilitate informed decision-making and promote the transition to sustainable energy practices. The project also looks at oxygen, so-called oxyfuel combustion. The use of pure oxygen as a substitute for combustion air significantly reduces energy demand and increases reheating? furnace efficiency. Oxygen is also the other product obtained when producing hydrogen in the electrolysis of water, the most likely method for hydrogen production for Sweden.

SSAB is participating in Twinghy through Carl Ellström, who currently works in process development on the rolling side in Oxelösund. Jonas Engdahl from Borlänge joins him in the project.

What has happened in the project so far?
“We are looking at hydrogen heating of slabs before rolling. In practical terms, a plant in Spain is being expanded for hydrogen and tests will be carried out there with different combinations of hydrogen and natural gas. Due to the current poor availability of hydrogen, a flexible approach is needed.That’s how we work too, we have a slab furnace that can run on coke oven gas, natural gas and LPG.The advantage of hydrogen is lower CO2 emissions. At the same time, extensive simulation of combustion is carried out by another group in order for the gases to burn at an even temperature with optimal combustion.”

What will SSAB contribute?
“We are working with SWERIM to model the heating process for better precision and lower energy consumption.”

What are your hopes for the project?
“We look forward to increased use of green hydrogen in industry and through participation in this project, we will gain both direct experience and a better technical understanding of how conversion to hydrogen heating can be made, and the economic viability of such an investment.”

FACTS

Consortium: CELSA Spain, Fives Spain, Nippon Gases Spain, RWTH Aachen Germany, University of Oulu Finland, SSAB Sweden, SWERIM Sweden, BSC Spain, Calderys Spain.

SWERIM is SSAB's partner in this research project. SWERIM is building a model based on energy balance based on data from slab furnace 2 in Oxelösund.