More and more smokestacks taller than 500 feet are being built around the United States, according to the Government Accountability Office and the Environmental Protection Agency. For years, commercial and power plant chimneys were looked at as if they were celebrations of industry in the United States.
These commercial chimneys are not built to last forever, though they can last about three decades. The length of their lifespan is determined by a lot of factors, including the climate. Of course, if industrial chimneys are taken care of properly, they can last a lot longer.
In order to extend the life of a power plant chimney, it is important to understand the causes of deterioration of existing chimneys and smokestacks. The moment the building process for a smokestack or chimney has been completed and it is put to work, the deterioration process starts. Though, there may be no outward signs of this for at least a few years.
Once the signs become apparent, the process of deterioration will accelerate rapidly. This often results in the need for serious repairs and renovations. It is worth noting that paying close attention to chimneys before they start to fall apart and doing routine maintenance can prevent the need for extensive repairs.
There are three things to look out for with reinforced concrete chimneys for power plants.
- Flue gas can do a lot of damage. This gas often contains sulfur and other corrosive compounds that start to cause serious wear and tear on chimneys and smokestacks. When flue gas is able to reach the space between the chimney shell and the liner, it will initiate the production of acidic liquid.
- When the liner goes, so does the entire chimney. With no liner to protect the chimney, the gas will come into direct contact with the chimney itself. When this happens, the chimney will be subjected to both chemical stress and thermal stress, both of which can kill power plant chimneys.
- Carbonation can do a lot of damage to chimneys. This is the term for what happens when carbon dioxide comes in direct contact with the walls of the chimney. This can make its pH to decrease, which hurts the general integrity of the structure.
A big issue for many structures, including power plant chimneys is the weather they have to live through. Wind, changing temperatures, rain, and snow can all do a lot of damage to any kind of structure. Chimneys in areas that experience great temperature fluctuations are very susceptible to damage from the climate conditions.
Anytime there is wind, it is possible for a new airflow pattern to be created around taller chimneys and smokestacks. This displaces the air around the chimney, which then increases the velocity of the wind in the area. The result is often a patch of negatively pressured air, which can then pulls out the flue gas. As the flue gas comes in contact with the outside of the chimney, the change in temperature makes it leave deposits that are black, yellow, or brown.
The way the power plant chimney was built can increase or decrease its life span. For smokestacks that are around 500 feet, the process of constructing them involves putting together pieces that come in sections that are seven or 10 feet long. When the joints are colder, there can be problems with the bonding of the concrete. The space between sections provides a perfect way in for water and air to get in and start to cause the steel to break down. In addition to this, the concrete that is used on these larger power plant chimneys can only last between five and seven years.
The best way to deal with these problems is to conduct simple maintenance when the problems first appear and then complicated structural repairs when they get worse.
When smokestacks and power plant chimneys are first built, they look like they would be able to last forever and withstand anything. The best way to keep them in good shape is to pay attention and perform routine maintenance on a regular basis.