When we use the air cooler, the heat exchange tube often leaks. So what is the reason for this situation? Today, the editor will give you an analysis of the reasons for the leakage of the heat exchange tube of the air cooler.
1. Corrosion
In the petroleum refining process, the main corrosive substances to the equipment are: sulfur compounds, inorganic salts, naphthenic acid, nitrogen compounds, etc. Although the content of these impurities is small, the harm is great. In addition, the solvents and acid-base chemicals added during crude oil processing will also form corrosive media and accelerate the corrosion of equipment. The typical corrosion type for air coolers is the low-temperature (t<120°C) HCl-H2S-H2O corrosion of the atmospheric and vacuum unit, the constant-top condensing cooling system and the hydrogenation unit's fractionation tower top system.
2. Tube bundle corrosion (except for uniform corrosion of finned tubes)
The possible places are: the entrance of the finned tube medium, the inner wall of the finned tube bending downwards, the outer wall of the equipment fin tube near the tube box without fins, and the fin tube with liner at the end of the liner. The inner wall, the part where the medium vortex may be generated, etc. The inner wall of the tube bundle for dry air cooling and combined air cooling; there is no fin part outside the fin tube.
3. Defects and improper selection of tube bundle materials
As the nature of crude oil continues to deteriorate, the sulfur content in crude oil has increased in recent years, which has also led to the increasing corrosion of air coolers. Therefore, the selection of equipment has become more and more important, and improper selection of materials will lead to The service life of the equipment is greatly reduced. In addition, if the use time is too long, the heat exchange tube will also leak.