A different, but important, focus for climate change reduction relates to efforts to reduce steel corrosion (the electrochemical reaction that occurs when metals oxidize and begin to rust). This is because the process of corrosion gradually worsens global carbon emissions. In other words, the more steel that is used and the more it is allowed to corrode, the worse the contribution (notwithstanding some of the efforts made by the steel industry to address environmental concerns).
Replacing corroded metal a major environmental issue, according to research from Ohio State University. There are also economic cost savings to be made. In the U.S. alone, a trillion dollars fighting metallic corrosion. The current economic cost of corrosion is estimated to be 3 to 4 percent of the U.S. gross domestic product.
The objective, the researchers argue, should be to develop new ways to prevent steel from corroding. If corrosion can be reduced, then the need to replace steel is similarly reduced and with this the impact from the greenhouse gases released from steel production are similarly lowered.
A considerable level of energy goes into creating steel. This energy is lost as the steel reverts to rust, where the steel revers to its original form of iron ore. To replace corrode steel, a new energy input is required. Steel production accounts for 27 percent of the carbon emissions of the global manufacturing sector, and about 11 percent of the total global carbon emissions worldwide. The contribution from corroded steel replacement represents between 1.6 and 3.4 percent of all emissions.
Based on current projections, the greenhouse gas emissions produced by the steel industry could reach about 27.5 percent of the world’s total carbon emissions by 2030, with corroded steel representing between 4 and 9 percent of that number. This alone makes the goals set by the Paris Agreement to limit Earth’s warming to 1.5 degrees Celsius unfeasible.
The time taken for steel to corrode depends upon the severity of the environment and the quality of the steel – which is a product of its alloy composition. As well as the natural environment, a risk arises within healthcare and pharmaceutical facilities from chlorine-based disinfectants.
To address the problems relating to steel production requires finding ways to reduce corrosion and ways to decrease global steel demand (but without turning to plastics). This can be partly addressed through multidisciplinary approaches, although efforts in this area will need to increase substantially.
The researchers are seeking a coordinated approach to international policy, as they state in the research paper: “Our goals are to present a new perspective that has been ignored until now and spark debate in the scientific, engineering, and political communities on how to reduce the impact of corrosion on the associated CO2 emissions.”
The research appears in the journal Materials Degradation. The research is titled “The carbon footprint of steel corrosion.”
