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Alloy C276 Plate For Absorption Tower and Packed Column

The absorption tower and packed column consisted of various sections and components including vapour/liquid distillation & absorption, liquid/liquid extraction, catalytic separation, filter dryers and reactions and demisting compartments. On this occasion, NeoNickel supplied C276 water jet cut profiles for manufacture of the packed column trays.

Alloy C276 was selected as it allowed flexibility in design, after service and commissioning of the plant which utilised absorption towers for distillation and separation of corrosive liquids. NeoNickel supplied a full package of C276 plate, sheet, bar, flat bar (cut from plate), pipe and pipe fittings & flanges.

C276 is a solid-solution strengthened, nickel-molybdenum-chromium alloy with a small amount of tungsten, which exhibits excellent corrosion resistance in an assortment of harsh environments including strong oxidizers such as ferric and cupric ions, hot contaminated media (organic and inorganic), formic acid and acetic acid. Moreover, alloy C276 has an excellent resistance to localised corrosion (pitting, crevice corrosion and stress corrosion cracking) in both oxidizing and reducing environments. It also demonstrates outstanding corrosion resistance in brine and sea water applications.  Hence, C276 is generally selected as it allows flexibility in design, after service and commissioning of plants in the refinery, petrochemical and chemical process industries.


Corrosion rates in mixed acid media with chlorides & fluorides

Uniform corrosion mils/year

Corrosive media Temperature C22 C276 C4 625
6%HF + 5% HNO3 60°C 67 207 204 73
1%HF + 5% HNO3 Boiling point 0.5 8 11 1
25%H2SO4 + 5% HNO3 + 4%NaCl Boiling point 12 64 97 713
23%H2SO4 + 1.2%HCl + 1% FeCl3 + 1%CuCl3 Boiling point 7 55 2294 3847