In the frosty landscapes where energy infrastructure often ventures, understanding the behavior of soils under freezing conditions is not just academic—it’s a commercial imperative. A recent study published in the journal *Геосистемы переходных зон* (translated to English as *Geosystems of Transition Zones*) sheds light on how saline sands behave when subjected to artificial ground freezing, a technique widely used in the energy sector for excavation support and groundwater control.
Lev Yu. Levin, a researcher at the Mining Institute of the Ural Branch of the Russian Academy of Sciences in Perm, Russia, led the study that delves into the intricate dance of heat and mass transfer in moist saline sand. The research team initiated freezing from one end of sand samples saturated with varying concentrations of NaCl solutions, ranging from fresh water to a briny 104 g/l concentration. By meticulously recording temperature fields with thermocouples and tracking moisture distribution through drying, they uncovered some compelling insights.
“The freezing point of pore water in the sand samples decreased linearly with increasing NaCl concentration, dropping as low as -7°C,” Levin explained. This finding is crucial for energy projects in cold regions, where understanding the freezing behavior of soils can prevent costly infrastructure failures.
One of the most striking observations was the redistribution of moisture during freezing. In non-saline samples, moisture accumulated near the freezing front, a phenomenon attributed to the combined effects of thermodiffusion and phase pressure differences at the water-ice interface. As salinity increased, this effect diminished, reducing the contrast in moisture content between frozen and unfrozen zones.
“This weakening of the moisture redistribution effect with increasing salinity is a key finding,” Levin noted. “It suggests that in saline environments, the dynamics of freezing are significantly different from what we observe in fresh water systems.”
The implications for the energy sector are substantial. Artificial ground freezing is a critical technique for constructing and maintaining infrastructure in permafrost regions, where saline soils are common. Understanding how salinity affects freezing processes can lead to more accurate modeling and better engineering practices, ultimately reducing risks and costs.
The study’s time-space distributions of temperature and moisture provide a robust foundation for parameterizing mathematical models of heat and mass transfer in frozen media. This research not only advances our scientific understanding but also paves the way for more reliable and efficient energy projects in challenging environments.
As the energy sector continues to push into remote and harsh terrains, such insights become invaluable. Levin’s work underscores the importance of tailored solutions for different soil conditions, ensuring that the ground beneath our energy infrastructure remains stable and predictable.
In a field where precision is paramount, this research offers a clearer picture of the freezing process in saline sands, guiding engineers and scientists toward more informed and effective strategies. The journey to harness energy in extreme environments just got a little clearer, thanks to the meticulous work of Levin and his team.