In the August 2021 edition of Modern Casting, Eccomelt LLC’s low carbon replacement for A356.2 primary ingots, eccomelt356.2, garners the attention it deserves in an article entitled “Minimizing the Carbon Footprint of A356 Castings”. The article explores ways that foundries can minimize their carbon footprint, and explains that ” the contribution of melting, casting, heat treating, machining, etc. is very small compared to the carbon footprint of the purchased metal used for the castings, making recycling extremely important.” Foundries are no exception in the movement to lower carbon footprint across the manufacturing sector, and the biggest source of C02 comes from the primary aluminum these companies purchase to make their castings. It is now incumbent upon foundries not only to use low carbon-ingots, recycle internal runaround scrap, and manage their energy consumption, but most importantly, as the article shows, they must maximize recycled content in the new metal they purchase.
Co-authors Greg Wittbecker of CRU and Martin Hartlieb of Viami International, review the latest trends in “low carbon” aluminum brands, such as RenewAl (Rio Tinto) Allow (Rusal), Ecolum (Alcoa) and Reduxa (Hydro), and mention the inert anodes technologies that are being developed. All of these initiatives, though admirable, are “still far away from large volume production on a global scale”, and have growing premiums. The authors circle back to recycled aluminum, which uses only 5% of the energy of primary, at a carbon footprint of 0.673 t Co2e/t Al (in the case of ingots) and conclude that it should be the prime focus of foundries efforts to reduce the carbon footprint of their castings. The article makes special mention of Eccomelt’s innovative non-thermal process, which enables its carbon footprint cradle to gate to be 0.136 t C02/t Al, and 0.112t C02/t AL if shipped loose (without bags), as is often the case. At most, it has a 0.15% Fe content.
Wittbecker and Hartlieb reveal the carbon footprint of any type of customized metal mix that includes eccomelt356.2 (even if it is only 20% of the mix) to be the lowest of all the carbon footprints in their study by far(at 0.04), they also provide specific details of the benefits of eccomelt356.2 by comparing it other alloys: ‘’if you make a casting from 100% “global average” primary A356.2 ingots with a 70% process yield and no internal recycling, those castings would have a carbon footprint of 24.29 t CO2 e / t Al., But if you recycle internally and then replace just 20% of the primary ingots with eccomelt356.2, the carbon footprint drops to half of the original value, i.e. only 12.4 t CO2 e / t Al casting. If low carbon primary A356.2 ingots are used, the values are much lower, but the carbon footprint reduction by internal recycling and using eccomelt356.2 to replace primary ingots has the same effect of cutting the castings’ carbon footprint in half.”
The article also exposes the flaws in the reporting of the grading scale used to quantify and publish carbon footprint. Currently, many primary producers use the IAI standard and publish only “Level 1” (direct and indirect emissions of the smelter), which covers Scope 1 and 2 from the GHG Protocol Corporate Standard that is used to define “low carbon aluminum.” As the authors state, “without getting full Level3/Scope 1-3 numbers (covering the entire value chain including bauxite mining, aluminum refining, etc., and all the logistics), those publications [can…]be misleading”. All the more reason we need engineers like Wittbecker and Hartlieb to inform the industry, as they can provide a scientific analysis of the data based on a full perspective of all variables involved.
The innovation of eccomelt356.2 lies mainly in its proprietary, non-thermal process, which eliminates one carbon-intensive melting step. The process also provides an extremely clean metal, with minimal dross, and allows for high density to maximize furnace and transportation efficiency. Eccomelt LLC, located in both the US and Canada, is available to provide economical, extremely clean, chemically pure aluminum. Alongside Alcan R&D, Eccomelt LLC has developed a patented process that produces a specification alloy from aluminum wheels at a lower cost than traditional methods and creates a CLEAN CHARGE. eccomelt356.2 is a direct substitute for A356.2 primary aluminum, used by OEMs, Tier 1s, foundries, and die casters who are using eccomelt356.2 to cast high-quality automobile parts. Eccomelt LLC ships products to automotive OEMs and foundries within North America including the United States, Canada, and Mexico, and worldwide, such as France, Ireland, Italy, Serbia, Spain, Hungary, and the Czech Republic.
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