Episode Transcript
[00:00:10] Speaker A: Welcome to the EU Energy Projects Podcast, a podcast series from Enlida and France focusing on the clean energy transition for the European Union and the EU Commission funded energy projects that will help us achieve it. My name is Aretid Daradimu. I am the editor of the EU Energy Projects Podcast and your host.
[00:00:34] Speaker B: In this episode of the EU Energy Projects Podcast, I'm joined by Paolo Veronese, professor of Metallurgy at the University of Modena, who is going to talk about the Metal Wave project.
Welcome Paola, and thanks for joining us today.
[00:00:53] Speaker C: Thank you very much for inviting me and I'm willing to answer your questions, if any.
[00:00:58] Speaker B: Well, the first place to start is with what the Metawave project is and its background and what its aims are.
[00:01:09] Speaker C: Okay. We decided to give it this name even if it's not an acronym, because the original project name was more complex like High temperature heating processes with breakthrough microwave in digital technologies for increased energy efficiency. But it's too long. So MetaWave gives the idea that we are going to develop microwave based solutions addressing also the topic of having virtual power plants and digital twins, but with the main goal of replacing fossil fuel based heating systems with advanced microwave based technologies and in the meantime also to develop new materials, for instance refractories and susceptors which are functional to the processes and also to modify their properties by adding 2D materials to improve the microabsorption capabilities.
This project is rather interesting because it brings together 20 partners with we are coming from nine different countries with very different expertise. So it's a really synergic processes aimed at improving energy efficiency, reducing so the energy consumption and lowering the greenhouse emissions, and by the way by also increasing productivity. And we are focusing on three main sectors which are quite known for being energy intensive, like ceramics, firing tiles, in particular the asphalt and heating aggregates and the aluminum sectors. And in this framework the baking of the anodes which are used during the smelting process.
[00:02:54] Speaker B: But just to go back a step, why specifically microwave as the heating technology?
[00:03:00] Speaker C: Yes, we decided to use microwaves because of their volumetric, selective and rapid nature of heating.
And in this framework they are quite useful when you want to process multi phase materials or materials having a low thermal conductivities, and in this case materials which are not able to withstand high temperature gradients. So microwaves are the best choice when you want to rapidly heat even bulk materials without waiting for the long times which are usually required by heat transfer.
[00:03:37] Speaker B: And you mentioned the four different industries.
What are the sort of challenges and differences that have emerged with These, well,
[00:03:46] Speaker C: the industries that we are targeting, they are all characterized by a very high energy consumption. And there were some challenges because you cannot make make a completely new process.
In case of the ceramic firing, the main idea was to replace the current gas burners with plasma torches powered by microwaves. And in that case we are able to reduce the amount of gases flowing in tunnel kilns, and so also saving a lot of energy because of the high efficiency of microwave plasma generation.
In case of the asphalt, the idea was to change from a process which nowadays, using extremely high temperatures, to heat aggregates, to a process that volumetrically heats the aggregates in all the bulk volume, but at a lower surface temperature. And this enables the use of recycled asphalt, which cannot be used nowadays in conventional systems. And the very last, the use of microwaves to bake anodes. Well, in that case, it was probably the most challenging condition because we are moving from a material which is basically an electrical insulator when it's cold, and after baking, it becomes an electric conductor. And that's why we had to involve not only microwave heating, but also induction heating. So coupling two different heating methods and moving from what is nowadays performed in large quantities, with hundreds and hundreds of anodes being baked simultaneously for days, to processes dedicated to single anodes, which is the best for improving and assessing their quality.
[00:05:30] Speaker B: So what have been the major sort of milestone achievements so far?
[00:05:35] Speaker C: Well, I said that we are halfway along the project, and up to now we have completely demonstrated the laboratory scale, the feasibility of the process that we had in mind. In particular, we have already made the new, we call them recircular refractors because they are made by more than 80% of recycled materials by use of geopolymerization. And these materials, properly added also with other waste like copper slag, can be able to withstand temperatures also in excess of 1300 degrees, which is exactly the main target of the most high temperature probes that we have.
But in this project, we also have already developed new measurement systems based on fiber optics and thermal camera, which are particularly useful in harsh environments, like the ones of the Metawave project, where we need to measure temperature in presence of high temperature, but especially of high electromagnetic fields, which must not be perturbed by the measurement tools.
We use numerical simulation as well to design new applicators for microwaves, focusing not only on energy efficiency, but setting new objectives like the maximum allowable temperature gradient within the load, which is a relatively new approach and allowed us to design proper applicators.
Moreover, these models have been used to develop digital twins they are on their way. So these digital twins will allow us to perform experiments without really having the need to change completely experimental setup and so to optimize the conditions for our processes. And in this, the validation of these digital twins models will be performed thanks to the network of sensors that would be installed compliant to IEC 6149 standard, which allow the continuous monitoring of the main parameters of our systems. And this is going to lead to the definition of the so called virtual power plant, which is a way to use energy at its best, to use it when it's more available or cheaper, as you can guess. Also the economical aspect is not trivial. And so to have these processes running at full power when we have most availability of energy, but for instance, keeping them in steady state or posing them when there is less availability of energy or the energy costs are higher.
And in this framework, with the three companies we are working with, which is metal, and for the aluminum gresterragon for ceramic tiles and cofa for asphalt, we have already started the installations of the systems.
The system to bake anodes is already running in our facility and it's only waiting for temperature sensor installation.
The one dedicated to ceramic tiles firing has been already demonstrated at the lower volume. And we had plasma torches powered by six kilowatt microwaves, able to reach 1300s, which was 1300 degrees, sorry, which was the target temperature.
And for the heating of inerts for asphalt, where this really astonishing achievement of being able to process recycled asphalt, which usually being contaminated on the surface by the asphalt itself, it's difficult to process at high temperature. And in this case we are finalizing the tunnel kiln which will be used for this application.
[00:09:16] Speaker B: And can you expand a bit more on the next steps?
[00:09:20] Speaker C: Yeah, the next step, of course it's to and the installation of the prototypes in the final plants, most of them will be running in parallel with the existing processes, so that we are able to compare both productivity and energy efficiency enhancement. And moreover, the next large need is to connect all these prototypes to on the Internet, so that we can generate a lot of data which will be used to develop reduced order models and to better define what are the digital twins of our systems. And this will allow us to assess any possible critical conditions, if any, but also to identify the best conditions to
[00:10:06] Speaker B: run our processes and what steps are being taken to ensure that the solutions are both as sustainable and energy efficient as possible.
[00:10:15] Speaker C: Well, the project was already focused on these topics from the very beginning.
So we started already from the numerical simulations having as the main target the maximization of energy efficiency.
Then when we were thinking about the refractories needed for such processes, again we selected low environmental impact processes like geopolymerization, which is a kind of cold setting for refractories. And by the way, achieving excellent results in terms of low thermal conductivity of the refractories, which means for such processes, also, low energy consumptions, lower heat losses during the process.
And so we use this data coming also from simulation to estimate the expected carbon dioxide reduction in terms of emissions.
And in this, by also setting this vehicle power plant, we kind of have been able to map when it's better to operate with these processes, when it's better to go with conventional processes, or when use these new processes to boost the existing work. But this for environmental sustainability. But for the economical sustainability, we also run some calculations showing when the installation costs and the running costs are covered. And some of these plants have a payback time, really of few months in the framework of continuous producing, for instance, recycled asphalt.
So everything. Keeping also in mind that there is another kind of sustainability that we have to guarantee, which is the safety sustainability. So these equipment are intrinsically safe, because in case the microwave leakage is detected, all the generators are inhibited and they cannot emit microwaves any longer. So they are already compliant with existing standards. But we added this extra feature for the safety of the operators and other
[00:12:17] Speaker B: specific emission reduction targets.
[00:12:21] Speaker C: Well, when we first met together with all the partners, we had in mind to achieve a minimum guaranteed heating efficiency of the processes, ranging from 70 to 90%, which in practice it translates into reducing energy consumption by 30%, which if we take into account the current production of the compounds which are involved, it amounts more or less to 420 gigawatt hours of energy saved.
And this of course, is expected to reduce emissions proportionally.
And we quantify these in more or less 95,000 tons of carbon dioxide emission saved. But this was at the very beginning.
Now, after making the simulations and running the prototypes, even at a smaller scale, I can give you more precise figures. For instance, in ceramic tile firing, we are able to save 38% of energy.
And this by also recovering the heat from the gases which are being used in the plasma torque.
For the case of heating aggregates, we have an astonishing more than 50% savings of energy. But what is really probably the most promising aspect is the possibility of processing recycled asphalt for the baking of anodes. It's a more complex situation because we are not implementing in our processes the recovery of the volatiles or post combustion of gases.
But if these were implemented in that case, by moving from conventional gas firing to microwave heating plus induction heating, we can save more than 52% of energy.
So these are the main advantages that we at the moment we have been able to quantify.
[00:14:10] Speaker B: And to what extent can the solutions be adapted to other energy intensive industries?
[00:14:16] Speaker C: Well, in principles, some of the solutions that we had in mind can be already used to retrofit existing plants. For instance, if you think about the plasma torches, they have dimensions which allow them to replace existing gas burners. So not only in the ceramic industry, but for instance, in the heat treatment of metals or the glass sector, this is quite a straightforward, easy way to adapt to other applications.
But this is not only the option, because by having direct generation of heat, like in the case of heating of aggregates, we can translate this to other materials characterized by low thermal conductivity. This already happened in the food sector, of course, but now we can move to more, let's say, complex inorganic materials, thermal insulators, in particular refractories and so on.
And the idea of coupling microwaves and induction heating, which is what we are doing for the anode baking, is another successful example of a technology which is adapting to a load which is changing as you process it. Because we start with an insulator, we end up with a conductor.
So a pure microwave heating could not work like a pure induction heat. It could not work. But coupling the two allows to process these carbon based materials very successful. And in this we have also a kind of cooperation. We have a project running parallel to ours, we're not involved in it, which for instance, use microwaves to produce carbon fibers for composite material. So as you can see, it's quite a straightforward transferring to other activities if needed.
[00:16:08] Speaker B: And are the solutions quite easy to install or do they take up much, you know, they're bulky or require much adaptation in the industry.
[00:16:20] Speaker C: Okay, let's say when it comes to replacing burners, the torch itself, it's not bulky, more or less, the dimensions are the same of the burners. The micro generation part is some. Something more, let's say bulky, but there is space around the kiln to install for the generators.
It's completely different if we change the approach, because in the case of heating of aggregates, we move from a very high temperature trommel furnace with temperatures in excess of 1000 degrees C to a process which stays below 200 degrees C, because the final temperature target was to heat these aggregates at 70 to 200 degrees C maximum. So in this change, we, in this case, we really changed the way the process is working. So moving from a trommel to a tunnel kiln with a conveyor belt. And this may require some changes in the loading and unloading sections of the plant, but that's it.
The main difference is when it comes to anode baking, because we are moving from this huge batch processing to single processing of each unit. And in this case it's a completely revolution of the way the anodes are baked. But in this case we can guarantee a much better quality and reproducibility of the heat treatment.
[00:17:42] Speaker B: And what are the plans to ensure the uptake of the solutions beyond the end of the project?
[00:17:48] Speaker C: Well, the project itself was already involving quite detailed dissemination program which ranges from participating to exhibitions in the three sectors to scientific publications.
And we think that this dissemination was already affected because some of the partners have already been contacted by other industrial partners trying to investigate the applicability of some of our new processes to their products or even simply to transfer those solutions.
Of course, the uptake is not only something which depends on dissemination, but depends also on the will of the people to adopt a new solution.
And I must admit that when it comes to microwaves, there is a kind of skepticism which comes from the use of radiation. So people is worried about the term they're using waves that you cannot see.
That's why we have invested a lot on making the equipment quite safe.
You have possibility to measure in real time what are the emissions, if any, from the plants, because two out of three are continuously open plants where you have input and output ports. And in that framework, the new susceptors that we have developed developed allow to attenuate any possible microwave leakage, making the system really safe from the operator point of view.
[00:19:21] Speaker B: Okay, good. Well, thank you very much, Paolo. And we look forward to following the progress of the project as it progresses.
[00:19:30] Speaker C: Okay, thank you very much. And don't forget to visit our website where there will be the most updated news and achievements that we we have.
[00:19:41] Speaker A: You've been listening to the EU Energy Projects Podcast, a podcast brought to you by Enlit and France. You can find us on Spotify, Apple and the Enlit World website.
Just hit subscribe and you can access our other episodes too. I'm Aretita Radimo, thank you for joining us.
