| dc.description.abstract | Deicers such as sodium chloride (NaCl) and magnesium chloride (MgCl2) play an important role in winter road maintenance. To apply deicers on winter maintenance in a more efficient way, the properties of deicers including ice melting capacity and ice melting rate should be evaluated accurately.
The purpose of this thesis is to develop the test of measuring ice melting rate of deicers with a calorimeter. The calorimeter was successfully used to measure the ice melting capacity in an accurate way and attempted to measure the ice melting rate with extreme assumptions on the salt concentration during the melting process in the previous study. So, the objective of this thesis is to explore the real salt concentration during the melting process, which could fill the gap of knowledge and improve the tests on measuring melting rate with calorimetry.
In this study, both tests that directly tracing the concentration in the calorimeter during the melting process and exploring the law of concentration development in more general conditions are attempted. Tracing directly was not successful due to the limitations of calorimeter and the failure reasons are analyzed for the future study. Regard tests that exploring in more general conditions, two deicers (NaCl and MgCl2) are designed to be tested at three different temperatures (-5℃, -10℃, -15℃). The salt concentration in meltwater and temperature of the samples are measured at different time points.
Based on the results, it is possible to find that the concentration would get closer to the freezing point concentration gradually and away from the solubility concentration during the melting. Also, at a specific temperature, the Percentage Value might start around a certain value and end with a certain value during the melting process. New assumptions are proposed and applied on the tests at -15 ℃. Compared with the results of previous assumption, new assumptions can achieve some improvements. | |