L-Aspartic acid (L-Asp) poses a dual function, which can affect the evaporation and crystallization process of the high-salinity brine by altering the physical or chemical properties of the salts. MSWI (municipal solid waste incineration) fly ash washing leachate, as a typical high-salinity brine, is utilized here to validate this hypothesis under the simulation guidance. Since L-Asp has stronger adsorption energy on the (110) crystal face of CaCO