Separation performance of flotation column with dilution water in pulp zone

Flotation columns show a good separation performance for fine coal slime and have been widely used in coal preparation plants. In this study, to reduce the ash content of the concentrate, dilution water was added to the pulp zone of the flotation column. Tailings discharge was also correspondingly increased to ensure the balance of coal pulp in the flotation column. The results indicate that ash content and yield of concentrate decrease with the increasing dilution water. The flotation efficiency index increases initially and then decreases as the rate of dilution water increases, and the highest flotation efficiency index is obtained at a dilution water rate of 0.18 cm/s, this indicates that appropriate addition of dilution water in the pulp zone improves the separation performance of the flotation column. In addition, the closer the dilution water is to the bottom of the flotation column, the better the separation performance of the flotation column becomes. Moreover, compared with a conventional flotation column with a feed pulp concentration of 40 g/L, the flotation column with dilution water has a similar pulp concentration in the pulp zone and shows a better separation performance.

Automated summary

The study demonstrates that adding dilution water in the pulp zone of a flotation column can improve separation performance by reducing ash content and concentrate yield. The optimal dilution water flow rate should be around 0.18 cm/s, and positioning the dilution water closer to the bottom of the column enhances separation efficiency. Compared to a conventional flotation column, the use of dilution water results in similar pulp concentration in the pulp zone and better separation performance.