Kaolin also called Chinese clay is a soft white solid that is an essential element in the manufacture of porcelain and porcelain, and is widely used in the manufacture of paper, rubber, paint and many other products.
The name Kaolin comes from a hill in China (Ka yenu Ling) that has been extracted for centuries. The prototypes were sent to different parts of Europe by the French as an example of the material used by the Chinese in Chinese production.
It is mostly used in the coating industry and is washed to remove impurities. Kaolin has the structure of the clay is, but, unlike talc and Mica, etc., its value in the production of more coverage of its share in the optical properties of it.
It is an economic term used for almost white deposits. These deposits often contain ore or products that are obtained from Yen. In the past, the term Chinese soil was used as a synonym of Kaolin. The name comes from the Chinese word meaning the White Hill where the soil is extracted. white porcelain soil is the most widely used in the production of porcelain and ceramics. The United States, Russia, the Czech Republic and Brazil are the largest producers.
Its Stone is divided into soft and hard bond groups according to the type of bond.It is stable in industrial chemical conditions.
Thin crystal plates give good coverage strength and are better for coating on paper and paint. It is often used in industrial as a liquid polymer suspension or Verde. The viscosity of these liquid smears is important. Basically, the value is high in solid percentages due to its very low viscosity. This property is the opposite of the property of bentonite.
This product is first processed in dry form, which includes crushing, drying and softening, which is the product calcined used in ceramics, paint and rubber. Processed wet or rinse with water, minerals, non kaolin from the liquid conductive separates, in this stage kaolin as filler and coating comes to hand.
In a variety of sieves, cyclones and liquid clay can be concentrated up to 30% solid in the settling tank and with a centrifuge of particles with a size of 2 micrometers from the coarse particles can be removed by ultra flotation method. And then the peeling process is sieved filtered and dried, and sometimes calcined.
In the other case, the liquid is divided into two groups, small and large, by centrifugation, hydro cyclone or separation with water, and then the ferrous iron compounds are washed from it. After evaporation by evaporation, rotary or compression suction filter, cake ca
n be removed and dried or transferred to the material with 70% solid for trade.
Its particles are mechanically separated into light and thin particles and calcined at 500 degrees Celsius to form a characteristic crystalline structure. This action increases the brightness.
Even the best types in the world has about 20 percent impurities. Therefore, they should thicken and the alkali of should be reduced to less than 1.5%.
The consumable must have the following characteristics:
1-the percentage aluminum is more than 30%.
2-the amount of iron not more than 1%.
3-the amount of titanium oxide should be reduced to 0.2 percent.
6-increasing the amount compared to other existing minerals.
7-the melting delay of kaolin should be about 1700 degrees Celsius.