The aging effect of plaster of Paris

                                                 The aging effect of plaster of Paris

New making or calcined plaster of Paris is typically stored after this process, called the aging process. Some plaster of Paris after aging can make its physical performance has been improved to varying degrees of, however some gypsum powder processing equipment for processing of plaster of Paris by Chen but to reach this goal. What if the plaster need to aging and aging mechanism, these problems has aroused the attention of scholars both at home and abroad, because the mechanism of research for stable building gypsum plaster of Paris Chen and the quality of the products is of great significance.

After calcination of plaster of Paris (rheological properties of building gypsum) will change in the process of storage, this is because the gypsum production equipment caused by absorption of water vapor in the air. Retrogradation degree of building gypsum has obviously affect the water demand and hardening speed, such as the water reduce this feature before and after aging for production of low water demand of high-strength gypsum and gypsum board production secondary processing products save dry heat loss is very good.

Opinions vary on aging mechanism at present, one of which is that used in the method of dehydration p type half water gypsum type (including Ⅲ anhydrite and not dehydration of dihydrate gypsum) is an aggregate of tiny crystals, in the high energy state. At this time, such as add cold water, tiny grain damage and loss of energy. Another theory is that in wet air, part of the high energy state of calcium ion and sulfate ion as a vehicle for the adsorption of water transfer to the crystallization of crack, the decrease of the surface area slowly lose energy. Lose energy of grain even if the water is not to undermine, these phenomena can be seen as p type gypsum to type a plaster.