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Based on the background information regarding the different types of corrosion in atmospheric and vacuum distillation units mentioned earlier, the following are the key areas where anti-corrosion measures must be taken regularly: First, the initial condensation dew point area of the tower top cooling system. This area suffers from the most severe corrosion throughout the entire unit, as it is exposed to a highly corrosive environment composed of HCl, H₂S, and H₂O. The risk of corrosion due to concentrated hydrochloric acid in this initial condensation zone is extremely high; therefore, it is necessary to implement regular anti-corrosion procedures using the “one removal and three injections” method. At the same time, wall thickness monitoring through regular measurements is essential to prevent corrosion-related leaks at the inlets of air coolers and water coolers. II. The high-temperature side line area in the middle and lower sections of the vacuum distillation tower: This area is subject to both high-temperature sulfur corrosion and naphthenic acid corrosion; it affects the tower walls, packing, extraction pipelines, as well as the associated heat exchangers along the second, third, and fourth extraction lines. It is necessary to regularly monitor the iron ion content in the oil from these side lines, to add high-temperature corrosion inhibitors, and to check for signs of packing corrosion and thinning during shutdowns; material upgrades may be required when necessary. III. High-temperature areas such as heating furnace tubes and oil transfer lines: The temperature in these areas generally exceeds 240°C, and they are subject to the combined corrosion effect of high temperatures, sulfur, and naphthenic acids. High-flow media further exacerbate erosion corrosion; therefore, it is necessary to regularly check the wall thickness of the furnace tubes and conduct corrosion coupon analyses to monitor the effectiveness of high-temperature corrosion inhibitors in forming a protective film, thereby preventing localized corrosion and perforation of the furnace tubes. IV. Other auxiliary components that require regular anti-corrosion treatment include the upper trays of atmospheric pressure towers, as well as the air preheaters and flues in heating furnaces. These are subject to corrosion caused by low-temperature HCl and sulfuric acid dew point, respectively; therefore, regular corrosion inspections and anti-corrosion maintenance are necessary to ensure the long-term operational efficiency of the entire installation.