Every year, the United States spends nearly a trillion dollars fighting metal corrosion, which is an electrochemical reaction that occurs when metals oxidize and begin to rust. By tackling this surprisingly insidious issue, researchers have now estimated how much erosion is gradually exacerbating global carbon emissions.
Global steel production has been rising steadily for decades—and because steel has such a poor resistance to corrosion, part of that demand is to replace steel used in building materials that have worn out over time, in everything from bridges to cars. Reducing the amount of steel that must be replaced due to corrosion could have measurable effects on the amount of greenhouse gases that are produced to make steel, said Gerald Frankel, co-author of the study and professor of materials science and engineering at Ohio State. University,
Although previous studies have estimated the current economic cost of corrosion at about 3 to 4% of a state’s GDP, this new study, led by Ohio State University Mariano Iannuzzi, is the first to quantify the environmental impact associated with steel corrosion.
The study was recently published in the journalmaterial degradation npj.
“Given society’s dependence on coal fuel, iron and steel production is one of the largest greenhouse gas emissions of any industry,” said Frankel. “But most of the costs associated with the industry actually stem from the energy that goes into making the steel, and that energy is wasted as the steel reverts to rust, which is like its original form of iron ore.”
Frankl said the time it takes for steel to corrode depends largely on the severity of the environment and alloy composition, but this environmentally costly problem is getting worse.
Using historical carbon dioxide intensity data to estimate annual carbon dioxide levels starting in 1960, the researchers found that in 2021, steel production accounted for 27% of the global manufacturing sector’s carbon emissions, and about 10.5% of all global carbon emissions. all over the world. Replacement of corroded steel accounts for about 1.6 to 3.4% of emissions.
But the study indicated that there is some good news. Because of the regulations placed on the steel industry, technological advances in the steelmaking process have resulted in a 61% reduction in energy consumption over the past 50 years.
Despite this improvement, the study’s findings are a call to action for policymakers and industry officials to adjust and harmonize international policy regarding steel production and corrosion management, Frankel said.
“Coordinated international strategies, in addition to reducing global demand for steel, through the use of corrosion mitigation best practices, can better improve global corrosion management strategies and significantly reduce the rise in greenhouse gas emissions that we are seeing due to the replacement of frequently corroded steel,” He said.
If actions are not taken to improve steel’s carbon footprint soon, the study suggests that greenhouse gas emissions produced by the steel industry could reach about 27.5% of the world’s total carbon emissions by 2030, with corroded steel accounting for about 4 to 9% of all carbon emissions. that. number. Such an outcome would make the goals set by the Paris Agreement to limit global warming to 1.5°C as well as the domestic climate goals of the United States almost completely useless. The study suggests that management strategies such as leveraging machine learning techniques could be one of the best opportunities we have for reducing carbon dioxide levels on Earth.
However, if humans cannot meet these conditions, the consequences for the Earth’s climate will be severe, so more people need to realize that the low-carbon steel industry is necessary to prevent such a grim reality.
“Global warming is a societal challenge that requires the coordination of a lot of multidisciplinary approaches,” said Frankel. “Our work highlights an issue that seems to have gone under the radar in terms of the importance of adding more to the problem.”