The Study On Inhibition Of Crystallization By Sodium Acetate Trihydrate Supercooled Solution

The supercooled solution of sodium acetate trihydrate is prone to crystal precipitation during long-term storage.This phenomenon will seriously restrict the use and thermal storage performance of sodium acetate trihydrate in long-term thermal storage units.Based on our previous exploratory research work,we found that adding a certain proportion of thickener to sodium acetate trihydrate can significantly inhibit the crystal precipitation of sodium acetate trihydrate supercooled solution.In order to obtain the thickener with the best effect of inhibiting the crystallization of sodium acetate trihydrate supercooled solution,we screened out fifteen thickeners from five types of commonly used thickeners,added them to sodium acetate trihydrate,and an experimental study on long-term stability of sodium acetate trihydrate supercooled solution was carried out,the experimental samples that meet the long-term stability requirements were subjected to several heating and cooling cycle experiments to test their excitation temperature and latent heat of phase transition,and the scientific discussion was made on the inhibition mechanism of crystal precipitation after mixed the thickener.Through the research on polyacrylic acid thickeners,it was found that when maleic acid thickeners were mixed into sodium acetate trihydrate with 42% water content,the supercooled solution had no crystal precipitation during 120-150 days,and its excitation When the temperature is around-13°C,the latent heat of phase transition does not decrease.Therefore,maleic acid is the thickener that can most effectively inhibit the precipitation of crystals in supercooled solution of sodium acetate trihydrate.Experiments have shown that the maleic acid thickener can significantly improve the stability of the supercooled solution after mixing with sodium acetate trihydrate in an indoor environment.It meets the conditions and requirements for long-term storage of phase change heat,and provides an effective way and method for using sodium acetate trihydrate to realize long-term cross-season heat storage in the future.