Abstract
We studied the compositions of various scales obtained from common salt making factories by chemical analysis and X-ray diffractive methods. Analysis were made on about fifty samples taken from the preheater and evaporator of vacuum system or thermocompression system equipments, and “Shijoka” or net type concentrating installation. We found that the principal component of scales from vacuum system evaporator or preheater is calcium sulphate, and that of thermocompression evaporator or preheater consists of calcium carbonate, magnesium hydroxide and calcium sulphate, but that of evaporator or preheater of vacuum system is calcium carbonate, when used the brine concentrated in flowing down salt field.
