Material selection issues for 70% phosphoric acid concentration reactors
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What material should be used for a 70% phosphoric acid concentration tank with a maximum temperature of 110 degrees? . The enamel-lined reactors we’re using now won’t do; they suffer from severe corrosion. . Hero, please help……
Could you provide more details about the operating conditions? If that’s not convenient, you can also send me an email; I can have our laboratory abroad check the data under these conditions. baoseti@sohu.com or ahuang@alleghenyludlum.com
I checked, and it seems that a graphite lining might work; I’m not sure though if it’s actually feasible. . Listen to the issuer's opinion
At 70% and 126 degrees, 904L/Sanicro28/254SMO/654SMO can be used to ensure a corrosion rate of 0.1–1 mm per year; at 70% and 90 degrees, the corrosion rate is less than 0.1 mm per year. So for 70% and 110 degrees, one of the above 4 options can be used
What we did for a company in Suzhou was to provide graphite linings for reactors, which offer excellent corrosion resistance.
The details regarding 254SMO aren’t very clear; there might be some issues. INCONEL825 can be used for heat exchangers in phosphate production
It is recommended that you choose a reactor lined with PTFE
This post was last edited by starsday on 2009-8-28 at 15:29. Harris Corporation developed the G-series alloys years ago specifically to resist corrosion caused by phosphoric acid; however, the advancement of super stainless steel technology has rendered the G-series alloys obsolete in the market. Generally, super stainless steels can meet the requirements of such applications, such as AL-6XN, 926, 254SMO, etc. – these materials are commonly used by first-class equipment manufacturers in China. Here are some example values: AL-6XN: corrosion rate in 85% phosphoric acid at 70 degrees Celsius
Alloy 825 will do
The corrosion resistance of metal materials can be found in relevant tables; Hastelloy B alloy or (20C-30N) material can be used