Plaster is the powdered form of gypsum, obtained by firing (calcination). The gypsum, in other words, bihydrate calcium sulfate (CaSO4*2H2O) is fired at as low a temperature as 150-160°C. Since the plaster hardens quickly when it is mixed with water by absorbing the water it has lost it is used in buildings, relief and decoration, orthopedics, dentistry, sculpture, and also for desalination of soil. It is used as a coater in the construction sector with additional additives. Firing time is directly proportional to its water content.
Plaster Production Technology
Since gypsum delivered to the plant is generally 300-500mm, it is crushed initially. Gypsum is delivered to the feeding unit through a belt conveyor and the crushing process commences there. The size of gypsum reaches 0-10mm after the crushing process. The material stored upon crushing is fed to the kiln. Feeding of raw plaster to the kiln is carried out through an auger conveyor. Steam forming in the kiln is discharged through the pipe system. The firing (calcination) process takes 1-3 hours at 130-160°C. The material is then discharged to the storing bunker. Calcined gypsum is delivered to the gypsum grinding mill upon the stocking-cooling process. The material processed to the required size during grinding is separated with a separator and is sent to the material stock ready for packaging. The grinding of larger material is continued until the required fraction is obtained. All processes are completed upon delivery of the stocked material to the filling machine. The production of plaster ready for delivery to the market is carried out briefly at Varlık Makina Plaster Production Plant using this method.
Construction Chemical Plant