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Special Report

80ºC is critical temperature for the and 9) the ease of maintenance and Consulting Resources Corporation,
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Care should be taken that the re- Hileman, B., Long, J.R., and
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immediately after shutdown to pre- sion. Sudden changes in operating pres- Chlor-Alkali Plants, Pamphlet #
vent migration of the caustic from sure and flow velocity may generate 10, Chlor-Alkali Producers outside
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2+
As higher concentration of Ca and and crevice corrosion. Non-uniform New York, (1976).
Mg ions accelerate corrosion, the heat transfer can lead to the formation Bertram, B.M., Sodium Chloride,
2+

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be avoided at temperature > 77 C. rect contact between such metals should Coin, R.J., Brine Treatment, 16th
o

Ti surface may be cleaned by be avoided by design of by insertion of Annual Electrode Corporation,
immersing it in 35% HNO – 5% insulators. However, the insulating ma- Chlorine/chlorate Industry Seminar,
3
HF solution for 2-5 minutes terials, gaskets, and seals may lead to Cleveland, (2000).
followed by a water rinse. crevice corrosion. Leakage of air may Davis, W.H., Open Cell-Room Ope-

accelerate general corrosion of carbon rations, 24th Chlorine Institute Plant
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196 Chemical Weekly December 3, 2024

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