Issues with the material of the trays in atmospheric pressure towers
Thread Content
What material is both economical and practical for use in the trays of atmospheric distillation columns in crude oil distillation? The Q235-B we use becomes severely corroded after just two or three years!
Analyze the materials in detail and handle them accordingly. If corrosion resistance for Q235 is required, 304 will suffice; it’s not too expensive either
At high temperatures, 0Cr13 is sufficient, but it must not be contaminated during installation; overall, it is more economical than 304.
302 should be a good choice – it is cheaper than 304, yet offers better corrosion resistance than carbon steel. The fillers we use here are made of 302, and after two years of use, there has been virtually no sign of corrosion
Looking at the situation with crude oil, I’ve seen 316 being used.
Also seeking information on the material used for the trays in the initial distillation tower; it would be helpful to know in which standard this information can be found. . The environment is high-sulfur crude oil; the design temperature is 240 and the design pressure is 0.4 MPa
Then replace it; stop using carbon steel Q235-B and switch to stainless steel 304, or choose a better material depending on the quality of the oil.
Considering double-sided corrosion, 304:victory:
304 will do; 316 is good, but it’s not cost-effective
According to SH/T 3096-2001, when processing high-sulfur, low-acid crude oil, the material for the trays in the atmospheric distillation tower is: “06Cr13 or aluminized carbon steel”’”； When processing high-sulfur, high-acid crude oils, the tray materials for atmospheric distillation columns are: “06Cr13 (for the top 4 layers), 06Cr9Ni10 (304), 06Cr17Ni12Mo2 (316), or ‘aluminized carbon steel’”. Therefore, the sulfur content and acid value of the crude oil must be tested, and the tray material should be determined based on the test results.
It ultimately depends on the properties of the crude oil; if its sulfur content is high, it is recommended to use 316. For distillation processes, the standard material for trays is 304 or 316, with 321 also being used in some cases. The use of Q235-B is very rare. If carbon steel had been chosen during the design phase, it seems that corrosion is not a major issue, and using 304 would be more cost-effective