Corrosion of 304, 316, 318 materials
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With increasing environmental regulations, various organizations have begun to implement \"zero-discharge projects for the evaporation and crystallization of high-concentration brine\" in recent years. During this process, the salt content in the solution (with typical components such as NaCl and Na2SO4) increases as concentration rises, which in turn raises the requirements regarding the corrosion resistance of the materials used for equipment and pipelines. Austenitic stainless steel 304 cannot be used in environments with high Cl- levels; however, it may be applicable when Cl- levels are low but other components are present in high concentrations. In cases of general corrosion, simply increasing the thickness of the material is sufficient. But currently, due to the high concentration of other components, steels of grades 316, 317, 318, or even higher are often used. Could this represent an overly conservative design approach that leads to increased costs?
No matter how good the material is, it will suffer from corrosion over time. It is possible to use materials that are resistant to corrosion and abrasion in order to protect the equipment in advance, and to carry out regular inspections throughout the period to ensure proper protection.
Yes, for intergranular corrosion in conventional equipment under normal pressure, using ordinary materials and conducting regular inspections along with timely replacements should be much more cost-effective
Material selection is not a one-time solution; periodic inspections are essential. Corrosion-resistant materials should be used, along with regular inspections and replacements.
I agree with you, but when it comes to long-term work, few projects see it through to the end successfully
As the mother liquor continues to evaporate and concentrate, the concentration of CL ions increases. In environments with high system temperatures, 304 material is prone to corrosion; titanium material is also easily corroded if the pH level is not properly controlled. To ensure the long-term stable operation of the system, I believe 316 is the minimum required material
With a high chloride ion content, titanium materials provide the best corrosion resistance. However, the specific usage environment still needs to be taken into account