481
Rectification tower is equipment of a kind of chemical industry, working object is a few mordant solution mostly, tower of acetic acid rectify also includes among them. To most metal considering acetic acid solution metropolis generation corrodes action, when choosing material of tower of acetic acid rectify to pledge so, want more careful, after all what material can accord with the making requirement of equipment?
Device of tower of acetic acid rectify reachs the job below more complex medium condition in higher temperature, its material must have a few special demands. Be more than 65 ¡æ to contacting temperature and the acetic acid that is less than 120 ¡æ , if contain machine or inorganic impurity, installation is fine choose the stainless steel that contain molybdenum; The acetic acid equipment that is less than 65 ¡æ to the contact chooses 18-8 austenite stainless steel to wait to also can achieve a requirement. The meeting in the thick acetic acid that because titanium is mixed,contains acetic anhydride is corroded, because this is mixed in second of high temperature armour,also meet in acid have crevice corrosion happening, do not suit to use this kind of data to not be more than the acetic acid equipment of 120 ¡æ . Additional, nickel and nickel alloy have better corrosion resistance in stainless steel of acetic acid geometric ratio, but because nickel and nickel alloy price are higher, so its apply got very big limitation.