The first aim is to meet the requirements of the users by eliminating the foreign matters in the raw coal, reducing the content of ash and sulfur, and improving the content of coal.
The second aim is to use and save the coal reasonably and effectively by dividing the coal into different specifications.
Besides, the flotation process can eliminate most of the ash and 50-70% yellow iron sulfur, which can reduce the environmental pollution.
However, when the gas capacity goes above a certain point, the air dispersion decreases.
With the rotation speed increasing, the air dispersion and the turbulence of the iron ore concentrator both increase.
The optimal fluid characteristics happened at the rotation speed of 2000rpm.
If the rotation speed goes higher continually, the turbulent effect increases, and then the flotation performance goes worse.
The fluid is fluctuated and the surface of the flotation cell is not stable for shallow cell. When the depth of cell increases, a stable flotation zone (bubble zone and separation zone) is formed, and the fluid characteristics are getting better.
Hence, the deep cell represents better flotation performance than the shallow one.
For the deep cell, the negative pressure is getting bigger, thus the bigger axle torsion is needed.
Compared to the standard cell (h=144mm), the best aeration rate is varying from 250 L/h to 300L/h and the best rotation speed is changing from 2000rpm to 2200rpm for deep cell.
The measurements of air dispersion accord well with the results of FLUENT stimulation, which shows the accuracy of the stimulation results.
Adjust the quality and recycle and control the processing capacity of the water which is used to make coal slurry are much important.
As for the quality and recycle, "over thick” should be avoided, especially when the coal materials are too fine.
The necessary dilution is the reasonable guarantee of quality and recycling in ore beneficiation procedure.