The wet process includes three stages of ore preparation, beneficiation processing and product processing. The preparation phase includes operations such as batching, crushing and sizing. The mash is to mix the kaolin ore with water and dispersant in the pulverizer. The mashing operation can disperse the ore. Prepare the appropriate fine kaolin slurry for the sorting operation, and remove the large sand at the same time.
The beneficiation stage may include hydraulic grading, flotation, selective flocculation, magnetic separation, chemical treatment (bleaching), etc. to remove different impurities. The prepared slurry is firstly removed by a sputum washing tank, a float classifier or a cyclone, and then divided into two parts by a continuous centrifuge, a hydrocyclone, a hydraulic sorter or a vibrating fine screen (325 mesh). Two grades of thickness. The fine-grained grade of the classifier is fed into HGMS (high-gradient magnetic separator) to remove iron-titanium impurities. The product is detached by stirring and scouring and then leached by iron oxide. The clay which is high enough in brightness and has good coating properties can be magnetically removed. Stripped and sent directly to the leaching operation. After leaching, alum is added to the slurry to coagulate the clay minerals to facilitate dehydration.
The bleached clay is dewatered using a high speed centrifuge, a rotary vacuum filter or a filter press. Dewatering by filter or filter press. The filter cake is redispersed into a slurry of 55% to 65% solids and then spray dried to make a loose dry product. Part of the dry product was mixed into the dispersed slurry to make 70% solids and shipped to the paper mill.
The final product, which is not selected, has low brightness and can only be obtained by magnetic separation, froth flotation or selective flocculation in the process. However, these independent operations have their own advantages and disadvantages, so the industry usually uses a combined process of two or three of these processes for the comprehensive utilization of clay resources.