The Department of Energy’s radical innovation arm targets the difficult decarbonization process of turning minerals into metals.
“We need to be able to provide those metals, but we have to do it in a different way,” he said. Christina Chang, member of the DOE’s Advanced Research and Projects Agency-Energy (ARPA-E).
The smelter uses about 4 percent of the world’s energy and produces about 7 percent of its global greenhouse gas emissions, Chang said, not including downstream emissions that occur when metals are re-melted and transformed. in materials or products.
“Our vision is the global production of metals using only air, water and clean energy as inputs,” Chang said at the ARPA-E Innovation Summit In the past week.
Clean energy can take the form of renewable sources to power all-electric smelting processes. Those processes can take the form of electrolysis in which metal oxides are dissolved in a solution of electrolytes. When electrical current is applied, metal migrates to one pole and oxygen to another.
If that electricity comes from renewable energy, the process does not emit carbon. And it may be possible to bubble hydrogen through the mixture to extract the oxygen as water, Chang said.
Basic technology exists today, but it is too expensive and too slow to be competitive, so ARPA-E hopes to foster innovations to overcome those challenges and develop technology that is economical and scalable.
Metals can also be melted by induction, the technology used in those smart stoves that will heat your pot but won’t burn your hand. The metals industry already uses induction for melting, Chang said, but not for melting.
More energy can be saved by melting and melting in one step, Chang said, about the status quo process of melting ore to make metal, melting metal to make material, melting material to make products.
In that way, new processes can have efficiency benefits as well as environmental benefits.
“Our legacy reactors, like the glass furnace to make iron, are not only inefficient and polluting, but they were designed and built so long ago that they don’t even fit well with the minerals we mine today,” Chang said. “Even with carbon capture as an interim solution, these legacy reactors have a limited life span.”
ARPA-E has issued a Information request of innovators who may come up with ideas for smelting minerals in highly efficient, clean energy-driven, and inherently scalable ways to meet the world’s demand for metal products. The deadline is June 14.