METHOD OF DIAGNOSING EMERGENCY STATE OF RESERVOIR Russian patent published in 2015 - IPC G01N17/02 

FIELD: chemistry.

SUBSTANCE: method of diagnosing an emergency state of a reservoir in a corrosion medium includes placing into it an electrode system, which contains the working electrode to be tested, an additional electrode and a comparison electrode, successive determination of the potential of the working electrode to be tested in an open circuit, the potential of pitting-formation, the resource of pitting-stability by the potential as the difference between the pitting-formation potential and an open-circuit potential. A control working electrode is additionally introduced into the electrode system and its potential in the open circuit is determined. Then the threshold value of the potential of the working electrode to be tested is selected. The control working electrode is connected to the potentiostat as the comparison electrode. The working electrode to be tested is periodically polarised at the zero value and at a selected threshold value of the potential, changing the duration of the polarisation period, with the registration of the current strength and the amount of electricity, which passed through the electrode system. A conclusion about the emergency state of the reservoir is made by the presence of pitting corrosion on the working electrode to be in the polarisation period, namely by the appearance of current fluctuation with a certain amplitude in the polarisation period, which is quantitatively evaluated by the value of the amount of electricity, which passed through the electrode system.

EFFECT: increased accuracy of diagnosing the emergency state of the reservoir due to the determination of the quantitative evaluation of pitting corrosion in conditions, close to real ones.

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