The issue of corrosion is highly relevant, both for the industry and for the economy of a country. In European countries and the USA it is estimated that the losses caused by this phenomenon are between 2 and 5% of the Gross Domestic Product (GDP). Due to the type of substances they handle, the petrochemical, chemical, pharmaceutical and naval industries are the ones that report the most problems related to corrosion.
Corrosion is the result of a chemical reaction that deteriorates metals until they are transformed into more stable compounds, either in the form of oxides or salts. The magnitude and speed with which corrosion occurs will depend on the environment in which it is generated; for example, humidity, the presence of corrosive material and high temperatures are factors that are frequently associated with higher levels of corrosion.
Avoiding corrosion has become a priority task for companies, since the damage caused translates into economic losses and, in extreme cases, endangers human lives.
Technologies and solutions that help control corrosion are a fundamental axis for safety and industrial competitiveness.
Corrosion in the Chemical industry
Many chemical manufacturing processes such as hydrochloric acid, sulfuric acid, caustic soda, hydrogen peroxide, and the like as building blocks or catalysts serve to produce the final products. Many of these chemicals are corrosive and toxic, which means they must be handled with care. Historically, such products were among the first to be produced, in some cases the history stretching back over 100 years.
The corrosive nature of such products was understood early on and materials of construction included lead lining, rubber lining, glass enameling and even in some cases the use of wood in some reactors and filters to control the corrosion problem.
The three most common causes for which facilities and equipment corrode are related to the type of substances that are handled:
- Aggressive substances for metals: aqueous solutions with different concentrations of salts. In addition, some physicochemical parameters that can promote corrosion are pH, oxygen and dissolved gases, hardness and temperature.
- Acid substances: solutions with corrosive acids such as sulfuric, hydrochloric, nitric and hydrofluoric acids.
- Basic substances: solutions with caustic hydroxides and hypochlorites.
In this type of industrial environment where highly corrosive compounds are present, the facilities normally require constant maintenance and care to avoid deterioration or destruction of the equipment.
Recommendations to avoid corrosion
In the high volume continuous processes used to produce most basic chemicals, materials of construction used to handle any corrosive products have been standardized PTFE and PFA liners where operating temperatures allow, both metals and exotic alloys where temperatures exceed 200 ° C and pressures are high.
SIESA's coated pipe systems are used to handle chemical products such as hydrochloric acid, hydrofluoric acid, chromic acid and various compounds derived from halogens, such as chlorides, bromides and fluorides. These systems do not require expensive maintenance compared to bare metal that requires constant maintenance.
Impact of corrosion in the industry
Corrosion is a problem that generates significant damage that not only impacts the industry but also the entire productive infrastructure of the country. A poorly attended corrosion problem can generate from small leaks to strong explosions in which the risks include the loss of human lives. Other minor but more common impacts are decreased equipment life, environmental damage, plant shutdowns, product contamination, damage to adjacent equipment, and hazardous conditions.
Due to the above, it is essential to take adequate measures that help control the deterioration of the facilities and that allow the design of new and future projects that include innovative materials.
Corrosion is a problem that affects the facilities, equipment and tools of various industries, including the chemical and petrochemical industry, and that has serious consequences in the productive, economic, environmental and health areas. For this reason, it is important to know the types of anticorrosive materials that exist and thus choose the most appropriate and consistent with the processes and substances used.