Title : Corrosion Issues
Abstract:
In the scientific and technical literature, there are quite a number of points of view on the mechanism of reactions between metals and liquid systems. However, the micromechanism of these reactions is not fully considered. But knowledge of this mechanism is necessary to create effective ways to protect pipelines from corrosion. Analysis of the current state of corrosion science shows that electrochemical and chemical approaches to the problem of introduction of oxygen atoms and other components of the liquid phase into the stable and often chemically very stable structure of metals and alloys prevail in it. It has become necessary to take generalizing conclusions from the works of M. Faraday as a theoretical basis for research in this scientific direction. In the XX century a huge amount of experimental material has been accumulated, which confirms the correctness of M. Faraday's views on the effect of electric current on chemical reactions.
Joint consideration of the classification of types of corrosion and the factors necessary to determine the methods of protection against corrosion leads to the following conclusion: the formulation of the concept of "corrosion mechanism", the classification of corrosion types and factors affecting the corrosion process, do not refer to the analysis of the mechanism of the chemical reaction, leading to the introduction of oxygen atoms and other chemical elements in the microstructure of the metal. That is, in fact, the results of corrosion destruction of metal and technological factors affecting the rate of destruction are considered. The mechanism of physical and chemical processes is not considered due to the complexity of taking into account the influence on the rate of these processes of the peculiarities of the microstructure of condensed systems, both solid and liquid.
The above indicates the complexity of electrochemical processes at the interface between the metal/environment, however, in the available literature there is not enough data on the influence of physical and chemical characteristics of the environment (general chemical composition of the medium, microstructure, intermolecular bonds, etc.).
One of the causes of electrochemical corrosion is believed to be stray currents, which result from the leakage of some current from electrical circuits into soil or aqueous solutions, where they enter metal structures. These currents can reach several amperes, resulting in great corrosion damage. For example, the passage of 1 A current for one year will cause 9.1 kg of iron, 10.7 kg of zinc, and 33.4 kg of lead to dissolve.
At the molecular level, the generation of static electricity is due to complex processes when electrons and ions from colliding heterogeneous surfaces with different atomic surface attraction bonds begin to redistribute. The faster the materials or liquids move relative to each other, the lower their resistivity, the larger the areas coming into contact and the forces of interaction, the higher will be the degree of electrification and the electric potential. It is well known, the electric discharge occurs on sharp edges, protrusions, including the protrusions of various sensors of the top of tanks of tanks and reservoirs.
In other words, "stray currents" for the most part are the result of triboelectric effects, which must be taken into account when creating technologies to protect metals from corrosion.
Audience take away:
- Explain how the audience will be able to use what they learn?
- The knowledge obtained will serve to improve research in the theory of chemical reactions and give grounds for clarifying the mechanism of corrosion.
- How will this help the audience in their job?
- The knowledge will help in the development and improvement of various devices to prevent corrosion damage to oil pipelines and other apparatuses in chemical technology.
- Is this research that other faculty could use to expand their research or teaching?
- This knowledge can be used to expand courses in theoretical chemistry and applications of theoretical development.
- Does this provide a practical solution to a problem that could simplify or make a designer’s job more efficient?
- This knowledge will make the work of designers and constructors more effective in terms of creating innovative methods to protect metals from corrosion.
- Will it improve the accuracy of a design, or provide new information to assist in a design problem?
- This knowledge will provide a new basis for solving practical problems in creating innovative technologies for protecting metals from corrosion.
- List all other benefits
- The advantage is the ability to prevent huge losses of oil during transportation through pipelines.
