The Most Valuable Things You Need to Know about Gypsum
The main component of gypsum powder is water-containing calcium sulfate (CaSO4 · 2H2O). Gypsum powder and cement, lime, asphalt, resin are also known as the five major gel materials.
It is widely used in construction, building materials, industrial molds and artistic models, chemical industry (sulfuric acid production, paper filler, paint filler), agriculture, food processing, pharmaceutical, and many other industries and applications, which is a very important industrial raw material.
It is usually white and colorless, sometimes may be due to impurities into gray, light yellow, light brown and other colors.
The applications of gypsum powder
This article will share the relevant content of gypsum powder from the use, price, market, selection and production process, hope to help you.
Uses of gypsum powder
Gypsum powder can be divided into the following 4 aspects according to its use:
1. Gypsum powder for construction: At present, the gypsum powder on the market is divided into raw gypsum powder and plaster of Paris, the plaster of Paris is divided into α-type gypsum powder and β-type gypsum powder, and the plaster of Paris is gypsum raw material after 105-200℃ high-temperature heating formed, also known as hemihydrate gypsum. The plaster of Paris is a kind of rigid gelling material. Although it has two kinds of materials, both are rhombic crystals. The physical properties of the two gypsum powders are different. The α-type gypsum powder has good crystallinity and solidity, and it can be used in ceramic molds, sculptures, gypsum lines, and high-end buildings. β-type gypsum powder is mainly used for wall screeding, gypsum board production, painting gypsum powder, etc..
α-type gypsum powder VS β-type gypsum powder
2. Gypsum powder for chemical industry: Gypsum powder can be used as portland cement retarder in the concrete industry. In agriculture, because much of the soil in the south is acidic, and gypsum powder is alkaline. It is possible to sprinkle gypsum powder into the acidic soil and integrate the ph of the soil to make use of a lot of land.
3. Gypsum powder for food: In the food industry, the official name of gypsum powder is called "food additive calcium sulfate", commonly known as "edible gypsum" and can also be used to make tofu.
The uses of gypsum powder
4. Gypsum powder for medicine: In the pharmaceutical industry, gypsum is the main medicine in the famous Chinese medicine "White Tiger Soup". It has a good effect in treating acute high fever, and thirsty irritable. In addition, dentists use plaster to make gum models, and surgeons also use plaster to fix fracture patients.
Market demand for gypsum powder affects its price
In recent years, the gypsum industry has developed rapidly, especially the gypsum building materials industry has continued to maintain a high-speed development trend. Gypsum building materials products are increasingly welcomed by the market and recognized by society, and their applications are becoming more and more widespread. According to the US mining forecast, the world's gypsum demand will increase at a rate of 2.5% in the next few years. It is estimated that the world's gypsum demand will reach 300 million tons in 2030, especially in the United States. The total annual consumption of the gypsum board will reach 2.04 billion square meters.
With the increase in the market demand for gypsum powder, the requirements for its production technology are getting higher and higher, so the price has risen accordingly. The price of gypsum powder is generally calculated in tons. The accuracy and use of gypsum powder are different, and the price is also different. The price of gypsum powder is between $28.8-$403.6 per ton according to the whiteness and fineness. The cooked gypsum powder is about $28.8-$158.6 per ton, the cooking gypsum is about $72.1-$317.2 per ton, and the refined gypsum powder is about $201.8-$720.8 per ton.
How to obtain the total cost of gypsum supply and useIn order to obtain the total cost of gypsum supply and use per ton of pure CaSO4 · 2H2O, the following information is required:
A. The landed cost at the farm gate of gypsum per tonne (gypsum + freight);
B. The cost of spreading or mixing in irrigation water per tonne of gypsum;
C. The purity, as percentage S (wet weight basis).
1. The ex-factory price of Australian recycled gypsum is $ 35.00 per ton, plus $ 25 per ton freight, which is $ 60.00 per ton at the farm gate, and $ 10.00 per ton to spread. Its purity is measured at 17% S wet weight. Total cost of gypsum supply and application per ton of pure CaSO4.2H20 = (35+25+10) × 18.6 / 17 = $ 76.59 per ton.
The total cost of gypsum in Australia
2. The ex-factory price of gypsum mined in New South Wales is $ 15 per ton, plus $ 40.00 per ton freight, which is $ 60.00 per ton at the farm gate, and $ 11.00 per ton to spread. Its purity is measured at 15% S wet weight. Total cost of gypsum supply and application per ton of pure CaSO4.2H20 = (15 + 40+11) × 18.6 / 15 = $ 81.84 per ton.
Buying and using gypsum powderThe world's major gypsum producing countries are the United States, Iran, China, Brazil, Canada, Mexico, Spain, Thailand, etc. The United States, Brazil, China, and Canada are rich in gypsum resources, and their reserves are among the highest in the world. Brazil has 1.3 billion tons, the United States has 700 million tons, and Canada has 450 million tons. The largest consumption area of gypsum is the building decoration material industry, which is mainly used to manufacture gypsum boards for construction and decoration. In many countries, the manufacture of slabs accounts for more than 80% of gypsum consumption.
Matters needing attention
How to choose high quality gypsum powder
1. When choosing, you can observe the color of gypsum powder. It is mainly divided into gray, yellow and white. Most of the gray gypsum powder is architectural gypsum. After careful observation or immersion in swater, small black particles can be found. This type of gypsum is brittle and commonly used for wall decoration.
2. For the same product, consumers are better to compare the materials and price at two or three merchants to determine the price range of the product.
3. When making, gypsum slurry has fluidity, so pay attention to the balance of liquid distribution. Gypsum molding process will release heat, but also will return to moisture, so don't worry in this process, otherwise, all the previous work is wasted.
Production process of gypsum powder
Building gypsum powder production line is usually divided into four parts according to technological requirements, which are the crushing system, the grinding system, the calcining system, and the storage and conveying system. The crusher crushes the large-scale gypsum ore into small particles less than 30mm and sends them to the mill for grinding. After grinding, the gypsum powder that reaches the required fineness of the product is sent to the rotary kiln for calcination by the separator, and the rest is returned to the mill for further grinding until qualified. The qualified gypsum powder after calcination is sent to the clinker bin for storage or sent to the product workshop for use.
Gypsum powder production process
1. Crushing system:
The gypsum raw material enters the crusher through the feeder, and the crusher crushes the large-size gypsum ore into small particles less than 30mm for use. According to the size of gypsum raw materials and different output requirements, you can choose the crusher of the corresponding specifications, such as PE jaw crusher, hammer crusher or impact crusher. In order to protect the environment, it can be equipped with dust removal equipment, to meet the environmental requirements.
2. Material delivery:
The crushed gypsum raw material is transported to the storage silo for use by the elevator. The storage bin is designed according to the requirements of the material storage time to ensure the stable supply of the material. At the same time, all parts of the material turnover adopted elevator to reduce the floor space.
3. Grinding system:
The gypsum raw material in the storage bin enters the Raymond mill by vibrating feeder for fine processing. An electromagnetic vibrating feeder is set under the storage bin, this equipment is interlocked with the mill to adjust the supply of materials according to the running condition of the mill. The materials are fed into the mill uniformly and continuously by the electromagnetic vibration feeder for grinding.
The pulverized gypsum raw powder is blown out by the air current blown by the mill blower, and classified by the analysis machine above the main engine. The fineness of the powder conforms to the specifications enters into the cyclone collector with the air current. After collection, the powder is discharged through the powder outlet pipe. The finished product falls into the screw conveyor and is transported to the next system for calcination.
The air current flows into the blower from the return pipe of the large cyclone collector. The whole system is closed circulation and flows under negative pressure. The amount of air in the circulation path increases because the raw material contains water, which evaporates into gas during the grinding process. This increased air volume is introduced into the bag dust removal from the pipe between the large cyclone collector and the blower to remove the dust in the air and then discharged into the environment to ensure the environment is clean. The particle size of the materials through the pulverizing system changed from 0-30mm to 80-120 mesh, which meets the fineness requirements of gypsum powder.
The process of grinding
4. Calcining System:
The raw powder delivered from the grinding system is sent to a rotary kiln for calcination. The cooked powder after calcination is transported to the finished product warehouse by the elevator.
The structure of rotary klin
Rotary kiln is a gypsum calcining equipment with high sales volume in the market. Its main structure includes kiln head, kiln tail sealing device, rotary cylinder, support device, supporting roller device, etc.. The kiln body is made of super-wear-resisting material newly developed in America, with good high-temperature resistance, impact resistance and toughness, low failure rate, service life is more than 5 times that of ordinary rotary kiln, and the quality is relatively guaranteed.
The finished product does not contain dihydrate gypsum
The quality of building gypsum powder processed by this production line equipment is good. Due to the use of low-temperature heat sources, gypsum is not easy to overheat. As long as the temperature of the material is controlled properly, the finished product does not contain dihydrate gypsum, and anhydrous gypsum is only within 5%, the rest are hemihydrate gypsum. This composition is ideal and the physical properties are stable.
The large demand and wide application of gypsum powder have stimulated the prosperity of many industries and fields, so the production of high-quality gypsum powder is the general trend of the gypsum powder industry in the future.
Fote Heavy Machinery
Fote Heavy Machinery (FTM), as one of the three major mining machinery manufacturers in China, has 37 years of experience. We are always ready to provide you with high-quality milling equipment and the best service.
For any questions about gypsum powder, please ask our professional engineers, we are looking forward to your inquiry.