Earth’s Cryosphere, 2020, vol. XXIV, No. 1, pp. 49-54
10.21782/EC2541-9994-2020-1(49-54)
INFLUENCE OF GAS COMPOSITION AND PRESSURE ON THERMOPHYSICAL PROPERTIES OF GAS-SATURATED FROZEN AND THAWED SANDS
E.M. Chuvilin1, D.A. Davletshina1,2, B.A. Bukhanov1, S.I. Grebenkin1, M.V. Ogienko1, Ch. Badetz3, J.V. Stanilovskaya3
1 Skolkovo Institute of Science and Technology, 3, Nobil str., Skolkovo Innovation Center,
Moscow, 143026, Russia; e.chuvilin@skoltech.ru
2 Lomonosov Moscow State University, Faculty of Geology, 1, Leninskie Gory, Moscow, 119991, Russia
3 Total S.A., 92078, Paris, 2 place Jean Millier, La Défense, France
Results of the experimental study of the gas composition and pressure effects on thermal conductivity and heat capacity of frozen and thawed sand saturated with different gases (nitrogen, methane, carbon dioxide, and a mixture of gases (50% CH4 + 50% CO2)) have been presented. According to results, the maximum gas pressure was set below the pressure of the gas hydrate formation. The experiments were conducted in a specially designed pressure chamber, which allowed to measure thermophysical characteristics of the gas-saturated sediments at temperatures below and above freezing point. The first ever data of gas pressure effect on thermal conductivity and heat capacity in the freezing sand saturated with different gases were obtained. The results revealed that thermophysical characteristics of the unfrozen gas-saturated sandy samples are practically independent of the gas composition and pressure. It has been established that a pressure increase in several saturating gases (N2, CH4, a CH4 + CO2 mixture, and CO2) cause a reduc-tion of thermal conductivity of the frozen sand, against an increase in the heat capacity. Carbon dioxide as highly soluble gas affecting the composition of unfrozen pore water, has the greatest influence on changes in the thermophysical parameters.
Key words: gas-saturated sediment, freezing under gas pressure, experimental modeling, thermal conductivity, heat capacity, methane, carbon dioxide, nitrogen
Please cite as:
Badetz Ch., Stanilovskaya J.V.Influence of gas composition and pressure on thermophysical properties of gas-saturated frozen and thawed sands. Earth’s Cryosphere, 2020, vol. XXIV, No. 1, pp. 49-54, DOI:10.21782/EC2541-9994-2020-1(49-54)