In order to separate non clay minerals and organic matter such as quartz, feldspar, mica, iron minerals and titanium minerals in kaolin and produce kaolin products that can meet the needs of various industrial fields, in addition to the purification and impurity removal of kaolin by gravity separation, flotation and magnetic separation, sometimes chemical bleaching, ultra-fine stripping, calcination Kaolin was treated by surface modification and other deep processing methods.
01. Hydraulic classification
Hydraulic classification includes spiral classification (separation + 1mm coarse sand), sedimentation tank classification (separation + 0.053mm fine sand), hydrocyclone classification (separation -0.053mm fine sand), centrifugal classifier or small-diameter hydrocyclone classification (for 0.002 ~ 0.010mm ultra-fine particle classification).
02. High gradient magnetic separation
The magnetic field intensity of more than 1600kA / M is generated by magnetic focusing medium to remove Fe2O3 and TiO2 in kaolin and produce papermaking coatings and advanced ceramic raw materials.
03. Selective flocculation
By adding flocculant, fine-grained quartz, pyrite, alunite and other impurities are selectively separated to produce scraper coated kaolin. Common flocculants include sodium hexametaphosphate, polyacrylamide ammonium, water glass, etc.
04. Chemical bleaching
Adding bleaching agents such as insurance powder can reduce the high valent iron of limonite and hematite in kaolin to soluble ferrous iron, or adding oxidant to oxidize pyrite and dyeing impurities to improve the whiteness of kaolin.
In the stripping machine, the fine medium ball is stirred to produce grinding and stripping effect, so that the kaolin aggregate particles are separated into thin crystals, and the production particle size is less than 2 μ Scraper coated kaolin with m content of more than 90%.
When calcined at 800 ~ 1000 ℃ in Rotary kiln, kaolin loses water, phase transformation, and some impurities volatilize to improve the whiteness and insulation of kaolin, so as to produce cable and rubber plastic filler. Calcination is a necessary processing method for coal series (hard) kaolin.
07. Surface modification
Kaolin is coated with coupling agent to improve its addition in plastic rubber, which is used to treat kaolin filler for rubber and plastic.
The mineral processing of kaolin can be divided into dry process and wet process. According to the properties and uses of kaolin, find suitable beneficiation methods to improve economic benefits.
The main equipment used in the process are jaw crusher, ball mill or raymond mill, spiral classifier, cyclone, magnetic separator, flotation machine, rotary kiln, etc.If you have requirements related to kaolin beneficiation, Fodamon engineers will configure appropriate solutions according to your actual situation.