BS ISO 8858-1:2019 pdf free.Hard coal- Froth flotation testing.
6.1 Flotation cell manufactured from stainless steel.
Figure 2 shows the dimensions of the flotation cell. The capacity of the cell with the deflector block and impeller in place is approximately 3,5 1.
It has been shown that the results obtained from laboratory froth flotation tests are very dependent on the procedure used to remove the concentrate from the surface of the pulp. For this reason, a deflector block manufactured from plastics material (see Figure 3) is used to guide the concentrate to a rectangular area in front of the impeller housing. The concentrate can then be removed by means of a scraper (see Figure 4) which is designed to cover the full width of the cell to a constant depth.
In order to establish the volume of pulp which can be contained in the flotation cell, the deflector block is fitted into the cell and water is added to the flotation cell to about 20 mm to 30 mm below the required pulp level. The impeller is started (air valve off) and additional water is added to the required mark (see &4). The impeller is stopped, the deflector block removed, and the volume of water in the flotation cell is measured.
6.2 Impeller assembly, of stainless steel and capable of rotation at frequencies up to 1 500 revolutions per minute (equivalent to a speed of 5,7 rn/s at the periphery). The dimensions of the impeller and diffuser are shown in Figures 5 and f.
The lower face of the impeller shall be positioned no more than 5 mm from the base of the cell.
Impellers constructed of other materials may be used, provided that it can be shown that the characteristics of flotation for the cell are similar to those obtained when a stainless steel impeller is used. To achieve this, different impeller rotational frequencies may be used if necessary.BS ISO 8858-1 pdf download.