GREENER ALUMINIUM 21
Why Inert Anodes are a Capital Idea By Paul Adkins* The entire primary aluminum industry has been watching carefully for any news from Elysis, the Alcoa/Rio Tinto joint Venture working to develop an inert anode. First announced in 2018, this project created a new level of interest in inert anodes following almost 20 years of speculation, trial and error and most of all, lack of a breakthrough. Since 2018, Elysis has kept an extremely tight rein on information. Even the usual “leaks” have not materialised. That’s left a vacuum, and as someone once said, speculation loves vacuums. There have been all sorts of expert opinion on the various questions arising from the possibility of an inert anode becoming commercially available. Technical experts have had plenty of time to consider these questions and challenges. How does a technology which occupies a vertical plane fit into an existing pot that operates on a horizontal plane? What if the raw materials required to make an inert anode generate other unpleasant side effects, or are simply too scarce or require mining in pristine areas? And anyway, who is going to teach potline crews how to deal with the various operating vagaries? Although potrooms look like they are sitting there happily bubbling away generating pure aluminum, that’s because the crews know exactly how to keep things that way. There’s no doubt the road ahead of the inert anode will be a difficult one. There’s speculation that Rio or Alcoa will retrofit an existing plant with the new technology, to make said plant into a model that Elysis can use to promote and market the technology. The concept of showcase plants is not new in the primary aluminum industry. Even then, we don’t know what market development strategy might get rolled out. The betting appears to be on technology licensing, which is also a very common practice in aluminum. But other options remain. Since the life cycle of an inert anode is said to be many times more than that of a carbon anode, could one centrally-located anode manufacturing
plant supply the entire world? (At least until enough smelters switch or new plants are built.) That model would gain synergies in procurement of raw materials, and would partially protect the technology from reverse engineering. Speaking of which, it’s my bet that whatever market rollout model Elysis decides on, China will not feature anywhere in their plans. Remembering that the Elysis CEO Vincent Christ used to work with Pechiney, and Pechiney got seriously burned by their technology being
illegally copied by some inside China, I can’t imagine any scenario where China will be a customer. Indeed, there are new moves inside China to tackle the inert anode, after previous attempts failed. So, there are many questions that we are all grappling with on the inert anode. I don’t claim to have any inside information, but I would like to offer one specific thought about this new technology. To me, it doesn’t matter what your view is on the technology, and it doesn’t
matter what outcomes you are looking for if you are examining the technology for your smelter, there’s one overarching fact – inert anodes are a capital idea. But in this case, capital means finance. The easy aspect of this statement is if you are considering building a new smelter. Your investment is going to be in the billions of dollars, regardless of whether you opt for existing technology or the inert anode. In a new smelter scenario, the only way forward that will deliver a return on investment in a decent time frame is to build a single potline now, and purchase anodes. You save yourself the cost of a full anode plant, though you still need a rodding shop and you still need to deal with spent anodes and any scrap anodes. Once the inert anode is proven and fully understood, you go ahead and build line two. (Naturally your new smelter is running on renewable electricity and green alumina.) In this scenario, you still have the question of operating costs. You have made your capital cost decisions, and it’s not too difficult to assess the operating costs of a potline that runs on existing prebake technology. Since you have a potline running, you can afford to wait and assess the case for the inert anode. Right now, nobody knows what the real costs will be – whether it is the cost of the raw materials, the cost of manufacturing the anode, the increased cost of electricity, or the cost of disposing of the inert anode at the end of its life. However, it is worth pointing out that these questions apply for those who might consider retrofitting their plant. Retrofitting is not an easy decision, but whichever way you look at it, it’s a decision involving major capital investment. Even a relatively small plant with say 400 pots will be faced with a major capital decision, since it’s not just the point of electrolysis that shifts. The meeting point where the electricity meets the alumina will shift to a vertical plane, but presumably the rest of the pot will need re-designing. Will centre point feeding still work or will a new feed mechanism be needed? Since the inert
*Managing Director, AZ Global Consulting Ltd Aluminium International Today
P Adkins.indd 1
July/August 2022
06/07/2022 12:52:50
