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Corrosion in fertilizer industry - 1.2 Elemental sulphur attack

WATCH THE VIDEO HERE OR READ ON BELOW!  Elemental sulphur attack is NOT sulphidation or hydrogen sulphide corrosion. It is an aqueous corrosion phenomenon. It considers two modes -  acidification of sulphur - formation of sulphuric acid 2.      direct cathodic reduction of sulphur with anodic dissolution of iron The lowering of pH is the main source of corrosion in both the methods. The phenomenon is temperature dependent. It increases with increase in temperature and becomes particularly severe above the melting point of sulphur (~112.8 degree Celsius). Hydrogen sulphide present in the petroleum may aggravate the sulphur attack by enhancing uniform pitting corrosion. Monoethylene glycol is used to prevent condensate formation ans may be present in traces in the feedstock petroleum. This enhances the sulphur attack in the form of uniform corrosion, and crevice corrosion. References:  Fang, Haitao, Brown, Bruce, Young, David, and Srdjan Nešic. "Investigation Of Elemental Sulfur Cor

Important terms in API certifications - CRV & IOW - II

CRV can be understood by using a simple example of milk kept for boiling in a pot on a stove. The motive, i.e. the reliability of this process has two main factors - 1) The milk should boil. 2) It should remain the vessel and not overflow. There are three critical variables here - Temperature  Why is this a critical variable?  Answer: The melting point of milk is 92 degrees C. That is the optimum level. If temperature is too low (30 degrees C), the milk may not boil at all. If the temperature is too high (200 degrees C), it may burn quickly. Vessel dimension = volume of milk is 1 ltr Why is this a critical variable?  Answer:  Vessel volume < 1 ltr, milk will not fit in it in the first at all. Vessel volume = 1 ltr, milk will fit, but will overflow on boiling Vessel volume >1 ltr, milk will fit and not overflow. Time Why is this variable critical? If the other two variable are at the optimum level, then -  Too less time (~ 1 min), insufficient for milk to reach boiling point Too m