Particle size analysis method - screening analysis

Particle size analysis

The size of the ore (meteogenesis block) is called the particle size. The samples used for the optional study or the materials processed by the selected plant are all mixtures of various mineral grains of different particle sizes. The mixture of ore particles is divided into several levels according to particle size, and these levels are called grain sizes. The shed size of the granules in the material is most called the particle size composition. The measurement of the particle size composition or particle size distribution of the material and the direct or indirect understanding of the particle size characteristics of the material, such as surface area, is called particle size analysis.

Particle size analysis is an important task that is often encountered in many industrial sectors. Such as the cement industry, metallurgical industry, coal powder preparation, work trials, and even food processing sectors "will be used in particle size analysis, it is also an optional research work in an essential test items. Granular analysis is often required for raw ore and products.

The particle size stripping method and its applicable particle size range are as follows:

There are many methods for determining the particle size, and there are more than ten known methods, which can be basically divided into four types, and the sedimentation analysis, the counting method and the ratiometric surface method are used for the screening and screening. Due to the complexity of the granularity problem, it is still difficult to have an all-encompassing omnipotent method in the test. In order to describe the particle size characteristics more comprehensively, it is often necessary to use several methods, which are complementary to each other, and generally adopt different measurement methods according to the particle size. Various measurement methods and their applicable scope are shown in Table 4-1. Screening analysis

The sieving method is used to divide the material into several levels of particle size analysis methods according to particle size, which is called sieving analysis.
Screening of coarse-grained materials In the beneficiation test, the sample size generally encountered is less than 100 mm. For materials with less than 100 millimeters of water and greater than 0.045 millimeters, the particle size composition is usually determined by sieve analysis. Wherein the size exclusion 6 millimeters to 100 millimeters materials, belonging to sieve analysis of coarse material, the use of steel or iron wire mesh holes god hand woven mesh to which method is to use a mesh sieve for screen sizes different The ore is divided into several grades, and then the weight of each grade is weighed separately. If the ore contains mud and water is high, and a large amount of slime and fine ore adhere to the large ore, they should be washed away to avoid affecting the accuracy of the screening.
The fine-grained material is sieved to a size ranging from 6 mm to 0.045 亳. The screening analysis is usually carried out in the laboratory using the test sieve.
Dry screening is to first set the standard sieve in order, pour the sample onto the uppermost sieve surface, put it on the vibrating screen cover, sieve it on the machine for 10~15 minutes, then remove the lowermost sieve. screening checked by hand in a blanket or glossy paper, resulting in a minute if the undersize material is less than 0.1 to 1% of the amount of material on the screen (this value is no uniform national standard of difficulty, and ore the nature, brittle materials requirements can not be too high) is considered to sieve analysis has been completed, or we need to continue sieve analysis. When the sample contains water and contains a lot of mud, the materials should be bonded to each other.