Gypsum

What is gypsum

Gypsum is a monoclinic mineral, the main component of which is calcium sulfate (CaSO4). Gypsum generally refers to gypsum and anhydrite. Gypsum is also known as dihydrate gypsum, hydrated gypsum or soft gypsum. It is usually in dense block or fibrous form, with Mohs hardness of 2. Anhydrite is anhydrous calcium sulfate, which is usually dense block or granular, white and gray white Glass luster, Mohs hardness of 3-3.5. China is rich in gypsum mineral resources, and the total proven reserves of various types of gypsum are about 57 billion tons, ranking first in the world.

Application of gypsum

With the rapid development of national economy, gypsum has been widely promoted and applied in different fields. Gypsum has been highly valued in the fields of construction, agriculture, thermal power plant, chemical industry, etc., forming a huge emerging industry, promoting the rapid development of circular economy.

1. Construction and building materials: the gypsum obtained by calcining gypsum to 170 ℃ can be used for coating ceiling, wood board, etc.; gypsum can be used as cement and cementitious material, and used as filler in plastic, rubber, coating, asphalt, linoleum and other industrial production; it can also be used as the main raw material of coagulation and expansion agent, anti cracking agent, self leveling mortar, etc.

2. Chemical industry: gypsum can be used to produce sulfuric acid and light cement; ammonium sulfate and light calcium carbonate can be produced.

3. Agriculture: gypsum can be used to improve soil and adjust pH; it can be used as calcium and sulfur compound mineral fertilizer in mushroom cultivation; it can be used as compound mineral feed additive in poultry and livestock.

Four Thermal power plant: with the continuous increase of environmental protection, the role of gypsum in thermal power plants is increasingly prominent. In the desulfurization process, choosing a good desulfurizer is the key to absorb sulfur dioxide. Limestone can be used as a high-efficiency desulfurizer. The smaller the particle size of limestone powder, the more conducive to the absorption of sulfur dioxide, the more efficient and rapid the combustion of flue gas Carry out desulfurization and purification.

Gypsum powder making process

The first stage: crushing of raw materials

The large gypsum material is crushed by the crusher to the feed fineness (15mm-50mm) that can enter the pulverizer.

The second stage: grinding

After crushing, small pieces of gypsum are sent to the storage hopper by the elevator, and then evenly and quantitatively fed into the grinding chamber of the mill by the feeder for grinding.

Stage three: grading

The milled materials are graded by the grading system, and the unqualified powders are returned to the host machine for regrinding after being graded by the classifier.

Stage four: collection of finished products

The powder meeting the fineness will flow through the pipeline into the dust collector for separation and collection. The collected finished powder will be sent to the finished product bin by the conveying device through the discharge port, and then packaged by powder loading tanker or automatic packer.