ИСТИНА

The process of hydrate formation in porous ice-containing medias is studied poorly.Paying attention to this fact we worked out a special experimental technique for studying hydrate formation in ice-containing sediments investigation. The sand and sandy loam samples with various degree of ice pores filling from 29 to 80% were used as the objects of studies. The experiments were carried out under constant negative temperatures in interval from -2 oC to -9oC. The hydrate-forming gases were methane and CO2. During the experiments the kinetics of gas consumption in porous media was investigated and also part of porous water turned into hydrate and hydrate- saturation of sediment samples were estimated. During the experiments it was determined that sufficient active processes of methane and CO2 hydrates formation take place in porous ice-containing medias under negative temperatures. Intensity of hydrate accumulation depends on degree of ice filling of pores, which defines a surface of ice-gas contact. It was experimentally shown that maximum hydrate-saturation of porous media occurs at optimum value of ice- saturation. The most favourable degree of ice pores filling is in range of 45-65%. If value of ice- saturation is more than this, hydrate formation reduces in consequence of decreasing of gas-ice surface. In the course of experiments the influence of porous media composition, type of gas and also the influence of phase translation of ice into water on the kinetics of hydrate accumulation in porous media were considered.