Calculation of the quantity of reagent-collector supplied to the pulp during flotation

Abstract

Purpose. Development of theoretical assumptions and methods for calculating a sufficient amount of surface-active substance (SAS) reagent-collector necessary for flotation enrichment, for example, fly ash from thermal power plants (TPP). The methods. Any cross-section of the surface of solid particles is a random function with alternating ridges and depressions in the projection. Comparing the surface of a particle with the surface of an oval or a sphere gives a deviation in a larger or smaller direction, that is, protrusions and depressions are formed. Depressions are the initiators of the accumulation of an excess amount of surface-active substance. Let's call them voids. To study the patterns of changes in the surface, it was useda statistical approach by visual examination under a microscope of surface irregularities of coal particles of TPP ash removal to determine the volume of voids. To obtain quantitative results, the ratio of the content of cavities to the volume of the particle was determined. The calculation of the amount of reagent-collector necessary to fill the voids of the surface of the particles was determined by comparison with the results of laboratory studies. Findings. The larger the size of the particles, the greater the change in surface roughness of the particle, the greater the content of cavities that will be filled by the surface-active substance and the smaller the difference between the surface of the ridges and the surface of the depressions. Thus, the amount of surface-active substance required for a satisfactory flotation process also depends on the particle size composition of the raw material. On this basis, a methodology for calculating the optimal (nominal) surface-active substance consumption for flotation of TPP ash was developed. The consumption of the collector reagent for the flotation of coal ash particles was obtained, which was 2989.6 g/t. The originality. Analytical ratios were obtained, with the help of which it is possible to estimate the content of voids in the particles of the useful component and their relation to the volume of the particle, and then to determine the required amount of surface-active substance for the flotation process. Practical implementation. The developed technique makes it possible to calculate the optimal (nominal) amount of surface-active substance necessary for extracting coal particles by flotation from TPP ash.