RUSSIAN JOURNAL OF EARTH SCIENCES, VOL. 17, ES5003, doi:10.2205/2017ES000611, 2017
I. K. Ivanova, V. V. Koryakina, M. E. Semenov, I. I. Rozhin
The study is focused on the results of kinetic analysis of processes of crystallization and melting of hydrates synthesized in model systems "natural gas + water" and "natural gas + asphaltene-resin-paraffin deposits (ARPD) + water". Synthesis and decomposition of hydrates in the systems under investigation were carried out in a calorimetric cell of differential scanning calorimetry (DSC). The kinetics description of processes is carried out applying the Avrami equation. Based on the obtained data, the rate constants, order of reactions, and half-life time periods of formation/decomposition of the hydrate-containing phase in paraffin deposits and water have been calculated. It has been determined that, with an increase in the water content of samples, the kinetics of crystal formation is determined by diffusion of a hydrate-forming agent in the liquid, and the process can proceed throughout the volume. The rate of hydrate-paraffin decomposition is two times less, in comparison with hydrates obtained in distilled water, which indicates the stability of the hydrate -paraffins. It has been identified that, with an increase of the water content in the ARPD emulsions, the degree of water conversion into hydrate decreases. Prediction of hydrate- paraffin formation in gas and oil wells has shown that P.T - conditions for hydrate- paraffin formation correspond to the actual thermobaric conditions of several oil and gas fields located in the permafrost area.
Accepted November 13, 2017.
Citation: Ivanova, I. K., V. V. Koryakina, M. E. Semenov, I. I. Rozhin (2017), Kinetics of cristallization and melting of hydrate - paraffins and prediction of their formation in oil wells of Nepa-Botuobian anticlise (Eastern Siberia), Russ. J. Earth Sci., 17, ES5003, doi:10.2205/2017ES000611.
Copyright 2017 by the Geophysical Center RAS.