Knowledge

Purification method of Diatomite Beneficiation

2018-09-21
Diatomite purification methods are mainly divided into: physical, chemical and physical and chemical synthesis method. 
1. Scrubbing method 
The precondition of purifying diatomite by scrubbing is to fine-grained the raw material by scrubbing, as far as possible to the consolidation of the diatom shell of the clay and other mineral impurities, for the separation and purification to create conditions, and then according to the different mineral properties and the range of particles, which quartz mud, iron ore, sand particles large, because the settlement can be first separated, And the clay impurity stone stirred scrub has been dispersed into very small particles, and diatomite with the same negative charges, mutual repulsion, so has good suspension and dispersibility, it can be in the slurry to add oxygen and other dispersants to strengthen the montmorillonite suspension and dispersion, montmorillonite particles are difficult to precipitate, The settling velocity of diatomite particles in slurry is much faster than that of montmorillonite particles, and the suspension with Montmorillonite as the main solution can be obtained, and the Diatomite is the main diatom soil. 
The specific surface area and pore volume of diatomite were Kong Wei by scrubbing method to remove some clay minerals such as montmorillonite and coarse sediment. The effects of scrubbing concentration, scrubbing time, scrubbing times and dispersing agents on the physical purification of Ai Xiansheng Monchey low grade diatomite were studied. 
The Scrubbing method can remove impurities outside the diatom shell, but it is not effective for removing impurities in the diatom micropore. The process of purifying diatomite by scrubbing is simple, the investment of equipment is less, and it is easy to realize industrialized production, but the area is larger, the water consumption is large, the production cycle is longer, and the drying energy of the diatom refined soil is larger. 
2, 2.2 acid leaching method 
By stripping the piece after pickling, remove most of the ore pulp iron and aluminum and other impurities, sedimentation grade the second time to obtain the 91.27% of the silicon content of diatomite concentrate, after coarse selection, stripping, acid leaching of concentrate to meet the expected requirements, the silicon content from 71.86% to 91.27%, effective removal of impurities, enhance the specific surface area, The production rate of the whole process is about 40%. 
Guilong Zhang has studied the modification effect of acid leaching on diatom pore structure, and concluded that the acid leaching method not only enhances the content of diatomite, but also modifies the structure of diatom pore, and the effect of acid leaching on the filtration performance and porosity of Diatomite was studied by Osman San. Diatomite filtration materials and porous ceramic materials were prepared by acid leaching diatomite. 
Wenfei and other people through the stripping of the piece after pickling, remove most of the ore pulp in the iron and aluminum impurities, and then by a single settlement classification of 91.27% of the silicon content of diatomite concentrate, after coarse selection, stripping, acid leaching of the final concentrate to meet the expected requirements, the silicon content from 71.86% to 91.27%, impurities can be effectively removed, There is a great improvement over the surface, and the production rate of the whole process is about 40%. Guilong Zhang et people studied the modification of the structure of diatom pore by acid leaching, and concluded that the acid leaching method could not only improve the diatom content, but also modify the structure of diatom pore. Osman San et people studied the effect of acid leaching on the filtration performance and porosity of diatomite, Diatomite filtration materials and porous ceramic materials were prepared by acid leaching diatomite. 
However, the conventional acid leaching method, which has long time of purification, large acid dosage, high cost, pollution environment and so on, is unfavorable to industrial production, which greatly affects its application prospect, and the study of microwave enhanced diatomite acid leaching technology not only can shorten the leaching time, but also improve the leaching rate.