Natural Gypsum Powder Production Line

Introduction of production line

Natural dihydrate gypsum (CaSO4·2H2O) is also called raw gypsum. After calcination and grinding, β-type hemihydrate gypsum (CaSO4·1/2H2O) can be obtained, namely building gypsum, also known as plaster of paris and plaster. If the calcination temperature is 190 °C, model gypsum can be obtained, and its fineness and whiteness are higher than building gypsum. If the raw gypsum is calcined at 400-500 °C or higher than 800 °C, floor gypsum will be obtained. Its setting and hardening are slower, but the strength, wear resistance and water resistance after hardening are better than ordinary construction gypsum.

The heating medium directly contacts the gypsum material to make it dehydrated into hemihydrate gypsum or anhydrous gypsum. The gypsum rotates forward in a small inclined cylinder, and the heating medium moves in the same or opposite direction. The gypsum dehydration is completed during the movement. Continuous feeding and discharging are continuous operations. Due to the direct fire, the thermal efficiency is higher than that of the externally fired rotary kiln. The fuel can be gas, oil, coal. The direct-heated rotary kilns produced are all calcined natural gypsum, and the fuel is coal. The energy consumption of calcining is about 220,000 to 230,000 calories per ton of finished product, and the product quality is better downstream. It is feasible to calcinate natural gypsum in a direct-heating rotary kiln. If the industrial by-product gypsum is calcined, it is not necessary to dry it before calcining, but the kiln body should have a certain length of drying zone, and the design of moisture removal and dust collection should be emphasized. The equipment structure of the rotary kiln is relatively simple, and it is a mature equipment and many manufacturers in China, and the equipment cost is lower than that of a wok. Has a price advantage.