Development of heated-brine-spraying system for concrete pavement deicing using latent heat thermal energy storage

Thin ice formed on the pavement at subzero temperatures is difficult to see and remove, which threatens road safety. Hence, this study introduces an eco-friendly deicing system that heats and stores brine at a minimum temperature of 20 °C using solar energy and latent heat thermal energy storage (LHTES) and sprays it immediately upon snowfall. The LHTES unit was constructed using 500 kg of n-octadecanol and was designed to heat 5 tons of brine solution to 20 °C above atmospheric temperature. The system was validated in a climate-controlled chamber at − 30 °C. The test was conducted for 5 h at a flow rate of 5 L/min, and 168 MJ of thermal energy was used to heat the brine. Brine heated to various temperatures was sprayed onto small, split concrete blocks covered with a 5-mm-thick ice layer. Additionally, a new method based on using infrared cameras to measure emissivity was employed to quantitatively analyze the deicing ratio. The results demonstrated that brine heated to 20 °C achieved a 94.5 % deicing ratio, compared to 0 % for conventional brine. The heated brine exhibited a 94.5 % higher deicing ratio than conventional brine, thanks to improved heat exchange and faster deicing speed due to its higher initial temperature. Finally, a system demonstration was conducted through a field test to evaluate the system's long-term road deicing performance. The field test confirmed the system's reliable and consistent deicing capabilities.