Harnessing the power of metals
Over the past decade, metal power as a research field has rapidly evolved at 黑料福利网: from studying the combustion of metals to also investigating the reduction of the resulting oxides back to metals, systems engineering and scaling up. Today, the topic involves multiple departments and a wide variety of valorization efforts with industrial partners. Assistant professor Giulia Finotello and associate professor Yali Tang from the Department of Mechanical Engineering share their experiences with and future plans for this field.
How did you get involved in metal fuels?
YT: 鈥業ron power research had been quite visible on campus for some time, with Philip de Goey developing the conceptual idea and demonstrating iron combustion for the first time. Meanwhile, Niels Deen joined his efforts on reduction or regeneration. Giulia and I were both introduced to the topic by Niels when we joined the Power and Flow group at the Mechanical Engineering department. This research topic immediately caught our interest because of our backgrounds in multiphase flow and chemical engineering, which are the key disciplines for metal fuel research.鈥�
What is it that fascinates you in the subject?
GF: 鈥楾his is a perfect topic to combine curiosity-driven research with making an actual impact on the world. There still are a lot of interesting fundamental questions that need to be resolved, for example about the routes you can take for the reduction of the metal oxide, the materials we use as a feedstock for the metal powders, and the reactor design.鈥� YT: 鈥業 fully agree. Metal fuel technology solves a very urgent societal problem, and at the same time, its development still requires fundamental research. This is what I have always been motivated to work on: application or impact driven fundamental research. And I clearly see what I can contribute, with my expertise on powder technology and multiphase flow.鈥�
Could you explain a little about your own research in this field?
GF: 鈥楳y focus is on using fluidized bed reactors for the reduction of iron oxide. Even though a fluidized bed is proven technology in the chemical industry, applying them to metal fuels raises entirely new questions. Cyclability is central: the powder needs to maintain its properties after repeated use. Understanding how microstructure evolves with each cycle is one of the open questions I find most compelling. I am also looking into flash reduction at high temperatures, which could dramatically increase the reaction speed. In addition to the reduction, I am also studying the production of iron powder, for example from different feedstocks. I look at how feedstock choice, including scrap and secondary materials, carries through into powder properties like size, shape and microstructure, and ultimately into cycle performance. Beyond metal power, this is also very relevant for other applications, like powder metallurgy or additive manufacturing.鈥� YT: 鈥業n the context of metal fuels, I also focus on reduction, and in particular with electrodeposition as a means to turn iron oxide or ore into metallic iron using renewable electricity, skipping the need for hydrogen. We鈥檝e already proven the concept of this novel electrolytic iron powder regeneration in the laboratory. But the 鈥渉ow鈥� remains a fascinating mystery due to the extremely complicated mechanisms. This is the puzzle I am going to solve over the next 5 years within my ERC Starting Grant project, using an interdisciplinary approach 鈥� combining advanced diagnostics, experimentation, numerical modelling, and material characterization. By understanding how, we can, and will, best design, optimize, and scale this process to produce iron fuels with the desired quality.鈥�
How is metal fuel research evolving at 黑料福利网?
YT: 鈥楾he challenges we face in further developing this technology are becoming increasingly interdisciplinary. So, one of the questions is how we can connect the knowledge and expertise that is available in different groups and departments, and advance it to create new cross-boundary knowledge.鈥� GF: 鈥楾o this end, we have set up a Metal Power community under the umbrella of EIRES. Besides the scientific and technological questions, there are also pressing challenges related to the process of implementation. Think of safety, stability, accommodating variability in the supply of hydrogen and electricity, and scaling up to a point where this technology can supply high temperatures to energy-intensive industries.鈥�
What needs to be done before metal fuels will be implemented at large scale?
GF: 鈥楩irst, we need to demonstrate that we can do the oxidation/reduction cycle multiple times in a reliable and robust way. Then, there is a scale up challenge. We need validated models and design rules that allow us to move from lab scale experiments to industrial scale systems without compromising efficiency, safety or powder quality. Beyond the technology itself, we also need to look into other aspects, like safety, social acceptance, and business models. At the moment iron powder is not a market commodity, so it cannot benefit from economies of scale or established supply chains. Until the ecosystem matures, we will need support from governance and industrial partners to create the required supply chain for metal fuels.鈥� YT: 鈥業ndeed, I think that it is imperative that we create ecosystems around this technology. In terms of science, we are in need for interdisciplinary research, ranging from material science and physics to understand metals to the scale of atoms, to process engineering, industrial innovation, and social sciences. When it comes to the deployment of the technology: currently, companies are mainly involved at the level of expressing their interest. We need to bring in targeted companies in the entire value chain, ranging from feedstock/energy supply to end users in sectors that are in need for heat or hydrogen. To this end, we are collaborating with Metalot to connect to a network of stakeholders from industry and government. We also have established close collaborations with startups like RIFT and IRON+, who are the key players implementing the technology itself. Personally, I am also taking part in a new startup called Eyzore, to jointly market our patented technology for the electrolytic iron powder regeneration.鈥�
Where do you expect we鈥檒l stand in 5 years from now?
GF: 鈥楳ore stakeholders will have become closely involved. Not just focusing on the powder and the burner, but on the entire supply chain, all the way up to the end user of the heat. I also expect that we will have a much clearer scientific understanding of how feedstock properties and production conditions translate into performance of the full cycle. That knowledge is what will allow the field to move from demonstration to reliable, scalable deployment. And we will see more initiatives and real cases where metal power can make a difference.鈥� YT: 鈥業 am convinced that in a couple of years this technology will have created real-world impact, via collaborative efforts across academia, startups, and industries 鈥� both inside and beyond 黑料福利网. My ambition is to take our electrolytic regeneration technology from a lab-scale breakthrough to a proven, pilot-scale reality.鈥�
Knight of metal fuels
On the occasion of his retirement las December, Philip de Goey was appointed Knight of the Order of the Lion of the Netherlands. During his farewell symposium, De Goey also received a signed Letter of Support from the Ministry of Climate Policy and Green Growth to work more intensively with Metalot and all partners on the further development of metal powder fuels. De Goey put iron powder on the map as a circular fuel. Besides leading multiple public-private research projects on the topic, he was also one of the founders of the student team SOLID, which laid the foundation for the startup RIFT. And he stood at the base of Metalot, which brings together 黑料福利网, TNO, RIFT, IRON+, and numerous other startups, companies, and universities that aim to exploit metal as a fuel.