Are there any acid water storage tanks made of stainless steel used in China? Solve? ? ? ?
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This post was last edited by saokun0880 on 2015-8-3 08:47. Are there any acid water storage tanks made of stainless steel used in China? Solve? ? ? ? Is the medium the acidic water from the acidic water stripping unit? ?
It wasn’t specified what type of acidic water it was.
Push it a bit? ? ? ? ? ? ? ? ? ? ? ? ?
In China, carbon steel materials are used for acidic water tanks, with coatings applied on the interior. Types of coatings include epoxy heavy-duty anti-corrosion coatings, epoxy + glass flake coatings, polyurethane coatings, etc.; abroad, epoxy + glass flake coatings are commonly used. In domestic cases, it is often related to construction quality, and in some cases it is related to the choice of paint. Pitting corrosion perforations on the outside of the tank indicate a problem with the coating inside. Acidic water contains phenols, which are solvents that can dissolve certain types of coatings. Its pH is around 9; it has a high concentration of hydrogen sulfide, as well as various other substances, along with small amounts of formic acid and acetic acid. The concentration of chloride ions is also high. Some factories achieve a certain degree of reduction in weld stress in storage tanks, while others do not eliminate weld stress; in such cases, epoxy anti-corrosion coatings with a thickness of over 400 microns can be used, providing a service life of more than 10 years. Using a stainless steel tank is a good idea; some corrosion tests are necessary. The main corrosive agents are high-concentration thiocyanamide and chloride ions, as well as electrochemical corrosion and weld cracking issues. As for the material, a brazed composite plate of carbon steel and 1mm thick 304L stainless steel could be considered (it’s not very expensive). If the lifespan is 8 years, it is more cost-effective than applying paint twice every 4 years.
Composite panels have been considered; the welding quality and difficulty are relatively high. Now consider all-stainless steel plates, and consider the effect of acidic water components on the corrosion of stainless steel. So I’m wondering if there are similar storage tanks available in China.
Epoxy heavy-duty anti-corrosion coatings with a thickness of over 400 microns can last for more than 10 years. Are there any practical examples? ? ? ? ? ? ?
It depends on whether the acidic water contains components that can corrode stainless steel
It seems there are such acid-resistant storage tanks made of stainless steel, but their price is quite high, so they’re not cost-effective. I read some information about them once; at that time I thought they weren’t a good deal and didn’t pay much attention to them. :)
Carbon steel lined with PTFE – works quite well! The original poster, please think about it! Let’s chat when you have time!
In fact, stainless steel such as Alloy31 can be used, and the results will be excellent, but it is extremely expensive. Generally, ordinary materials combined with an internal anti-corrosion layer are more commonly used, but controlling the construction quality of the internal anti-corrosion layer poses a challenge.
Corrosion is related to the composition of the medium, temperature, and pressure; for mixtures, it is advisable to have data from coupon testing for corrosion assessment.