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Concentration cell batteries are quite common in the corrosion of buried pipelines, including those based on differences in metal ion concentrations and those based on differences in oxygen concentration. Concentration cells are also caused, essentially, by the difference in electrical potential of the metals serving as the electrodes. In metal ion concentration cells, this difference arises from varying concentrations of metal ions in the electrolytes at the two electrodes; as the name suggests, oxygen concentration cells are caused by differences in the oxygen concentration in the electrolyte solutions at the two electrodes. Among them, oxygen concentration difference cells are the most common in the corrosion of buried pipelines. This has a lot to do with different soil properties. The oxygen concentration varies in different parts of the pipeline; in the oxygen-poor areas, the natural potential (unbalanced potential) of the pipeline is low, and these areas act as the anode of a corrosion galvanic cell. The rate of anodic dissolution in these areas is significantly higher than that on the other surfaces, resulting in corrosion. Pipelines pass through the junctions of soils with different properties; clay sections are oxygen-poor and prone to corrosion, especially at the junctions between two types of soil or near the end of buried pipelines where they emerge from the ground. In practical applications, buried pipes are often located in different compaction layers, resulting in varying soil porosities and, consequently, differences in the oxygen capacity. This creates the conditions necessary for the formation of oxygen concentration difference cells.