One of the consequences of air pollution that is seldom talked about is the effect of corrosion on man-made materials throughout the world. As air pollution levels have risen in industrialized countries, so too has there been a corresponding increase in corrosion levels. But this doesn’t just affect man-made monuments; it also affects things closer to homes such as vehicles, household electronics, outdoor furniture, and household tools.
Moreover, corrosion can cause damage to communication/data transfer facilities, industrial process control installations, sensitive production, and cultural heritage premises. In all of the applications above one needs to measure the corrosivity.
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Corrosion also degrades important infrastructure such as steel-reinforced- highways, electrical towers, parking structures, and bridges. In short, corrosion is a subject that bears further investigation, so that you can understand how this hidden degradation impacts your life.
What is Corrosion?
Corrosion is the process of decay of a material caused by a chemical reaction to its environment. Corrosion of metal occurs when an exposed surface comes in contact with a gas or liquid, and the process is accelerated by exposure to warm temperatures, acids, and salts.
Although the word ‘corrosion’ is used to describe the decay of metals, all-natural and man-made materials are subject to decay, and the level of pollutants in the air can speed up this process.
The reason is that airborne contaminants, such as corrosive particulate matter (PM), are created because of the chemical reactions between liquids and solids. These same liquids and solids, including salt and black carbon, can interact with the molecules within metals and accelerate decay.
Additionally, gaseous acidic contaminants have a major role in the corrosion of materials, either directly or indirectly as precursors of corrosive particulate matter (PM).
In fact, Sulfur dioxide that is generated by a power plant and vehicle emissions is one of the biggest contributors to corrosion. Sulfur dioxide is particularly aggressive towards copper contacts used in electronic equipment.
High levels of sulfur dioxide can also damage trees and plants by destroying foliage and inhibiting future growth. A recent analysis from Greenpeace also states that high levels of sulfur dioxide result in disastrous air pollution and premature deaths as well.
In other words, sulfur dioxide doesn’t just help degrade metal and other materials; it also results in disastrous air pollution that has some harmful health effects. The U.S. Environmental Protection Agency (EPA) has found that short-term exposure to sulfur dioxide can worsen asthma symptoms and make breathing difficult.
Atmospheric Corrosion Study Sheds More Light
A recent atmospheric corrosion study has helped to shed more light on how airborne pollutants directly affect metals in an industrial city environment.
Researchers began with the thesis that the atmospheric corrosion of metals and their alloys are very common in the industrial city environment due to the high concentration of corrosive pollutants in the air.
In other words, researchers theorized that air pollution in a major city would accelerate the corrosion process and help degrade metals faster than if the pollution was at a lower level.
To test this theory, researchers exposed various metal samples to an industrial city environment for 12 months to determine the effect of airborne particulates on the rate of corrosion. They chose an area within the test city that had a high level of pollutants.
The study found that metals corroded at a much faster rate during the winter when pollution levels were at their highest. This increase in pollution was caused by higher emissions generated by nearby power plants and heating plants, as well as from vehicle emissions and heating furnaces that were in wide use due to the cold weather.
The most common pollutants that accelerated corrosion were sulfur dioxide, carbon dioxide, dust, and humidity.
Additional contaminants resulting in high levels of corrosion include hydrogen sulfide generated by waste facilities; geothermal activity or anaerobic digestion of organic waste; nitrogen dioxide from traffic and combustion processes; hydrochloric acid; chlorine; acetic acid (the vinegar molecule); and process chemicals released to the environment.
Corrosion Hazards for Electronic Equipment
Corrosion induced equipment failure has been a fact since the mechanical telephone switch centers at the beginning of the 19th century.
The extensive use of computers and electronic equipment in today’s society together with the increasing pollution, especially in large cities and in industrial locations, puts even higher demands on finding solutions to lower the risk of failure.
Currently, communication and data transfer facilities are of great importance. One way to reduce the cost of cooling is to use “free cooling” or “air-side economizers” which refers to systems that allow outdoor air to filters pass into the room to provide direct cooling when outdoor temperature and humidity permit.
The Effects of Corrosion
So, what are the effects of corrosion that could actually affect your daily life or working environment?
Direct effects of corrosion may include:
- Damage to commercial airplanes or vehicle electronics
- Damage to hard disks and computers used to control complicated processes (e.g. power plants, petrochemical facilities or pulp and paper mills).
- Damage to server rooms and data centers.
- Damage to museum artifacts
- Costs of repairing or replacing household equipment that fails
“We know that many commercial industries such as oil and gas, paper mills, construction, and electronics used in a multitude of processes are vulnerable to the effects of corrosion,” stated Camfil USA Molecular Filtration Segment Manager. “Without control methods, there is likely to be equipment and structural failure that can have catastrophic consequences. That’s why molecular filtration is so vital to removing corrosive agents from the air and ensuring structural integrity.” Read more about corrosion control in our brochure.
Preventing Corrosion
There are several ways you can prevent corrosion from pollutants that cannot be removed at the source. First, you can use surface treatments on all metals to protect them from airborne pollutants. Second, you can galvanize all metal products, which makes them more resistant to corrosion. And third, you can invest in high-efficiency air filters to improve your indoor air quality and eliminate harmful pollutants that contribute to corrosion processes.
