What happened during the emergency repair of the absorption tower trays back then

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The last edit to this post was made by in the blink of an eye on 2018-7-13 at 19:11. I remember that around 2005, in the blink of an eye was transferred from a unit in the two-wing area to the command center for the plant’s key projects, and soon after that he was moved to the plant’s sulfuric acid production workshop. At that time, my mentor (who was also the workshop supervisor) was quite supportive of me and gave me the freedom to put my skills into practice. Right after starting my career, I was tasked with carrying out emergency repairs on the absorption tower trays. At that time, it was found that the circulating cooling water was acidic; after investigation, the scope of the problem was narrowed down to several absorption tower heat exchangers. At that time, both the first and second absorption towers in the sulfuric acid I system used plate exchangers (made of Hastelloy C276), with the acid side being laser-welded. On the spot, instructions were given to carry out repairs on the 2 plate exchangers that had experienced leaks; it was required that the large nuts on the pressure plates of these exchangers be tightened evenly, with a checkmark being made next to each bolt after it was turned 60 degrees. Through the above adjustments, the leakage from the plate exchanger in the second absorption tower was resolved, and it was confirmed that there were plate perforations in the plate exchanger of the first absorption tower. Since there were no spare acid coolers available at that time, the factory rushed to place orders for acid coolers; meanwhile, taking advantage of the fact that the cast-iron heat exchangers had not yet been removed, it connected the existing cast-iron heat exchangers to the acid circulating in one of the absorption towers. The emergency repair took 3 days and 3 nights at that time; in the blink of an eye, it was again 3 days and 3 nights without getting any sleep, and I could barely stand anymore. It was only later that it became clear that in absorption towers, Hastelloy C276 would inevitably suffer from corrosion and perforation due to the acid temperature at the inlet exceeding 90 degrees. A quick check on those two plate exchangers shows that their prices aren’t high; they are products from Nippon Sakai.