When refined oil was poured into the tank for sampling, the corrosion level of the copper sheet was found to be unacceptable; however, after a few days of settling, the corrosion level of the copper sheet became acceptable
Thread Content
When samples were taken from the refined oil inside the tank, the copper sheets showed unacceptable levels of corrosion; tests on samples taken from the tankers that had not yet delivered their cargo also yielded unsatisfactory results. After a few days of settling, however, the copper sheet corrosion levels in both the samples from the large tank and those from the tankers became acceptable. What could be the reason for this? When it fails the test, the copper sheet is purplish-red.
The sample taken from the top part is the one obtained by pouring oil into a tank for sampling, while the sample from the bottom part was obtained after leaving the oil there for a few days. I would appreciate it if someone experienced could give me some advice. Additionally, the oil sample taken right after sampling had a strong odor, but this odor faded after a few days. A sample from the bottom layer, after it had settled for several days, was also tested for copper sheet corrosion, and the color observed was merely a darker orange.
There are currently three possibilities: first, corrosive substances settle at the bottom of the tank; second, the corrosive substances evaporate; third, the corrosive substances get adsorbed by the tank walls.
In such cases, a doctoral-level experiment should be conducted first to identify the specific corrosive agents, after which a more accurate determination can be made based on the results. The doctoral experiment is very simple, and the conditions are easy to meet. I was wondering what the sulfur content standard is for refined oil at your company? Does it meet the standard requirements? The odor is strong and fades after a few days; it is likely due to light sulfur-containing impurities such as H2S. Heavy sulfur-containing impurities are generally sampled through a drain valve, and can be identified by visual inspection. The absorption by the tank wall can be ignored, unless there are deviations from the design parameters.
We don’t have the facilities here to conduct doctoral-level experiments. May I add you on WeChat to ask?
I’m not a professional in laboratory testing either; I only have a basic understanding of it. If you have such a need, you can contact me through the message system. Leaving contact information in posts goes against the forum’s rules: handshake
Do you have an alkali-deodorization device? Are the other two samples consistent?