Study: Steel Corrosion Causes Environmental Issues
A recent study from The Ohio State University is reportedly the first to quantify the environmental impact associated with steel corrosion. According to study co-author and professor in materials science and engineer Gerald Frankel, reducing the amount of steel that needs to be replaced due to corrosion could have measurable effects on how much greenhouse gases are produced to make steel.
The study was recently published in the journal npj Materials Degradation.
About the Research
According to a release from OSU, the United States spends nearly a trillion dollars a year to combat corrosion. Global steel production has consequently increased over the past decades because steel has poor resistance to corrosion.
Additionally, part of that demand is to replace steel used in construction materials that have become corroded over time, in everything from bridges to automobiles.
Previous studies have estimated that the current economic cost of corrosion is about 3 to 4% of the nation’s gross domestic product. However, researchers have reportedly now estimated that these efforts are gradually worsening global carbon emissions.
Up to 3.4% of carbon emissions are the result of replacing steel that has become corroded -- showing the importance of finding ways to prevent or reduce corrosion, a new @OSUengineering study says. https://t.co/SL0LVaFKUD— OSU Research News (@osuresearch) January 24, 2023
“Given society’s reliance on coal fuel, iron and steel production is one of the largest greenhouse gases emitters of any industry,” said Frankel. “But most of the costs associated with the industry actually stem from the energy that goes into creating steel, and that energy is lost as the steel reverts to rust, which is similar to its original form of iron ore.”
Frankel added that the time it takes steel to corrode largely depends on the severity of the environment and the alloy composition, but this environmentally expensive issue is “only getting worse.”
The study found that in 2021, steel production accounted for 27% of the carbon emissions of the global manufacturing sector, or about 10.5% of the total global carbon emissions worldwide. Corroded steel replacement reportedly accounted for about 1.6% to 3.4% of emissions.
To find these numbers, researchers used historical carbon dioxide intensity data to estimate carbon dioxide levels per year beginning from 1960.
On the flip side, the study noted that regulations placed on the steel industry and technological advances in the steelmaking process have resulted in a 61% reduction in energy consumption of the last 50 years.
Frankel said that the results of the study are a “call to action” to policymakers and industry officials to amend and coordinate international policy regarding steel production and corrosion management.
“Coordinated international strategies, as well as decreasing global steel demand, by using best practices for corrosion mitigation, could better improve global corrosion management strategies and drastically reduce the rise in greenhouse gas emissions we’re seeing due to repeatedly replacing corroded steel,” he said.
OSU reports that the study found 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 representing about 4 to 9% of that number.
This result would reportedly make the goals set by the Paris Agreement to limit Earth’s warming, as well as the U.S. domestic climate change goals, almost “completely unfeasible,” according to the report. Management strategies, such as taking advantage of machine learning technologies, could be one method to best reduce Earth’s carbon dioxide levels.
“Global warming is a societal challenge that takes coordination of a lot of multidisciplinary approaches,” said Frankel. “Our work is bringing to light an issue that seems to have gone under the radar in terms of the importance of adding to the problem.”
He also said that more people need to be made aware that a low-carbon steel industry is need to prevent such a dystopia if these conditions cannot be met.
Climate Change Impacting Corrosion
Back in September of 2021, a report issued by the Intergovernmental Panel for Climate Change warned that unavoidable rising sea levels will threaten saltwater intrusion on coastal infrastructure worldwide. To avoid metal and concrete corrosion, the IPCC pushed for a global investment for climate change mitigation.
According to the IPCC report, between 1901 and 2018, the mean sea level around the world rose 20 centimeters—higher than any other century for the last 3,000 years. In looking more closely at the numbers, from 1901 to 1971, the mean sea level rose about 1.3 millimeters each year. From 1971 to 2006, that yearly increase rose to 1.9 mm.
The majority of the sea level rise, however, occurred from 2006 to 2018, where sea level rose roughly 3.7 mm each year.
Since 1971, the IPCC attributes at least 50% of the rising sea levels to thermal expansion. Other contributing factors included melting glaciers (22%), melting ice sheets (20%) and changes in land water storage (8%).
From the research gathered, the IPCC estimates that two-thirds of the Earth’s coastlines will rise by 20% more than the mean global increase. Additionally, due to these rising levels, the extreme sea-level floods that once occurred every century would start to happen annually in half of the outlined locations by as early as the year 2100.
The report went on to further outline the severity of potential saltwater corrosion, noting on the recent collapse of the Champlain Towers South condo building in Surfside, Florida. The tragic collapse was reportedly the result of saltwater corrosion experienced within the structure’s basement. In a 2018 inspection report, it was noted that the building was suffering from “abundant cracking and spalling in various degrees.”
While many different governments have highlighted plans to mitigate climate change and better protect coastal communities, the IPCC adds that regardless of CO2 emission reduction or even elimination, that the rising mean sea levels would continue to increase for hundreds of thousands of years.