Electrowinning Iron?

Vincent J. Curtis

20 Mar 21

RE:  Building support for green steel in Hamilton by Eugene Ellmen.  Op-ed piece in the Hamilton Spectator 20 Mar 21.  Mr. Ellmen is a Hamilton based writer on sustainable business and finance.

The article was written by someone without technical sophistication, and the material the article was based on was intended to fool those not technically sophisticated.  It worked.  Image that, green steel by electrowinning, obviating the need to use carbon and produce carbon dioxide!  Fantastic, no?  Fantastic yes!

I studied an electrowinning process for obtaining metallic iron from ore in 1975 when I worked for the Algoma Ore Division of Algoma Steel.  I concluded that the chemistry of iron did not favor an electrowinning process.  The article shows that nothing has changed since 1975, and the process being advanced is for favorable publicity but without hope of realization before, or after, 2050.

The first sign of gullibility is that the author has no idea how much electrical power is required to make millions of tons of iron per year.  Even to contemplate the process you’re going to need a dedicated nuclear power generator to deliver all that carbon-free power reliably.  You need power to reduce millions of tons of iron ore to a colloidal powder (think talcum powder), and then you need more power to reduce the iron oxide to millions of tons of metal.  If you understood from the outset all the waste and pollution generated by the colloidizing process, in the spent liquors created by processing millions of tons, and that a multi-billion dollar nuclear power generation plant was needed to power the process, the idea that the steel produced was “green” might be questioned.  Such a process could never be economical as compared to the current process of the direct reduction of ore pellets by coke to pig iron.

Another sign of innocence is that the electrolysis process is a black box in the flow chart.  The literature shows only a generic electrolysis process, meaning they haven’t even figured out the electrochemistry for iron.  Another tell are the references to using hydrogen in the process.  Most people have no idea how dangerously explosive hydrogen is.  The current blast furnace process cannot afford to use coke that is too wet because at high temperatures, water decomposes to hydrogen and oxygen, and that free hydrogen can explosively recombine with oxygen in the cooler parts of the furnace.  Imagine a Saturn V rocket exploding on the launch pad, or the Hindenburg disaster, and you get some idea of the danger when tons and tons of hydrogen are being handled.

The reason why large users of carbon are putting out these speculations on electrowinning iron is that it keeps gullible politicians and other people off their backs with false hopes of eliminating carbon use.  Oh, and the government gladly funds research into these impractical ideas in the hope that something can be found.

Inadvertently, the author is acting as a shill for these large carbon users.

If the starting point for green steel were the construction of a multi-billion dollar nuclear generating plant, the environmentalists would cancel the whole project.

-30-