Material selection issue for methanol gas-to-gas heat exchangers?
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Material selection issue for methanol gas-to-gas heat exchangers? In the low-pressure methanol synthesis process, what material is suitable for use as the heat exchanger material at the inlet of the methanol synthesis tower for the methanol gas? 15 chromium-molybdenum, 20# boiler steel, 16 manganese, 304 stainless steel – what impact do these materials have on methanol synthesis?
15 chromium-molybdenum is usually chosen; what problems will arise if 20# boiler steel is used?
It is best to use 304 stainless steel, followed by 15 chromium-molybdenum steel; avoid using 20# boiler steel and 16 manganese steel.
After using 20# boiler steel, a certain facility found that the catalyst’s service life was only one year.
The corrosion resistance of stainless steel generally increases as the chromium content rises. The underlying principle is that when there is sufficient chromium in the steel, a very thin and dense oxide film forms on its surface, which prevents further oxidation or corrosion. An oxidizing environment can strengthen this film, whereas a reducing environment will inevitably destroy it, leading to the corrosion of steel.