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Let’s discuss the corrosion of industrial waste discharge pipes. The composition of the substances transported through these pipes is complex, and the acidic or alkaline substances present in wastewater can cause corrosion to the pipes； As the retention time of wastewater in the pipes increases, the dissolved oxygen and nitrates in the wastewater are completely consumed; the anaerobic conditions within the pipes facilitate the generation of hydrogen sulfide gas, and H2S causes corrosion to the pipes ； Sulfides in wastewater are converted into H2SO4 through a series of biochemical reactions, which corrodes pipes. Furthermore, for pipelines used to transport certain special fluids, such as oil field produced water, methanol must be injected into the gas production pipelines at the wellhead during gas field exploitation in order to prevent the formation of natural gas hydrates. This results in the creation of alcohol-containing wastewater in the gas field, and such wastewater accelerates pipeline corrosion. Factors that cause corrosion in pipelines in oily wastewater include pH value, dissolved oxygen, dissolved salts, CO2, H2S, bacteria, as well as changes in pressure and temperature. When CO2 and H2S dissolve in water, they form acids that cause corrosion of steel. Additionally, since O2 is a depolarizing agent, the O2 dissolved in water can exacerbate the corrosion of metal pipe walls caused by CO2 and H2S. Some microbial bacteria (such as iron bacteria) can obtain energy for their metabolism in neutral media by altering the valence state of iron ions. The ferric ions produced as a result of these reactions possess strong oxidizing properties, enabling them to oxidize sulfides into sulfuric acid, thereby causing corrosion of pipes. The anti-corrosion treatment of sewage pipes can also make use of internal lining technology; however, due to the complex nature of sewage, high-performance anti-corrosive internal linings are required. This requires us to continuously identify anti-corrosion coatings suitable for different media in pipelines in our future work, in order to solve these problems.