Flotation separation efficiency

Figure 10.18 further shows the flotation separation efficiency of galena and sphalerite from the date of the quantity containing Pb or Zn each other in the corresponding concentration. It may be seen that the recovery of ZnS in PbS concentration and PbS recovery in ZnS concentration are very low, indicating that the flotation separation of PbS and ZnS is selective in this new flowsheet. 

The flotation responses of the kaolin samples to the various flotation collectors were measured using the separation efficiency (SE) index. This index combines both grade and recovery to describe the efficiency of the beneficiation process. The mathematical expression used to compute the separation efficiency is the following ... 

Flotation is a complicated process. Its separation efficiency depends not only on the properties of suspended substances the volume ratio of the gas bubbles to the suspended substances, and the retention time of the flotation tank, but also on the bubbles size. Usually, the smaller the bubbles are, the higher the flotation efficiency is. This is simply because smaller bubbles can provide larger specific surface area for particles attachment. Therefore, generation of finely dispersed bubbles is highly desired for any flotation processes. 

A mixed granulate produced from PETP and PVC postconsumer bottles has been separated using the technology of column flotation. The aqueous separation medium pH and surfactant concentration were optimised with respect to separation efficiency, using Response Surface Methods. The study has shown that column flotation could be used to give close to 100% separation of PVC from PETP in a single operation. 15 refs. 

Aggregate Flotation. The investigations of the flotation process considered the same colloid-coagulant system as did the sedimentation studies (see List I). Likewise, the geometry of the reactors employed for (electro)flotation was kept as similar as possible to the geometry of the sedimentation tanks. And the evaluation of separation efficiency proceeded along the same steps of calculation as in the case of sedimentation. 

Hydrochloric acid ( 1 A/) is a suitable medium for formation of the associate. The concentration of tin(II) should be 0.02-0.04 M, and Rhodamine 6G should be in 50-fold excess with respect to Pt. At higher SnCh and dye concentrations the absorbance of the reagent blank increases. The amount of DIPE used in flotation has no effect on the Pt separation efficiency. The time of shaking should not be shorter than 1 min. After the washing with 2 portions of 1 M HCl the absorbance of the reagent blank is not higher than 0.05. 

An air flotation method was proposed for breaking o/w emulsions after its treatment with a cationic, high molecular weight flocculent. It has been found that in the presence of the flocculent the emulsion film is less stable than the starting pseudo-emulsion film, which determines the efficiency of the process [246]. The flocculent improves oil spreading on the water-air surface, thereby enhancing separation efficiency. 

Flotation. Flotation (qv) is used alone or in combination with washing and cleaning to deink office paper and mixtures of old newsprint and old magazines (26). An effective flotation process must fulfill four functions. (/) The process must efficiently entrain air. Air bubble diameter is about 1000 p.m. Typically air bubbles occupy 25—60% of the flotation cell volume. Increa sing the airRquid ratio in the flotation cell is said to improve ink removal efficiency (27). (2) Ink must attach to air bubbles. This is primarily a function of surfactant chemistry. Air bubbles must have sufficient residence time in the cell for ink attachment to occur. (3) There must be minimal trapping of cellulose fibers in the froth layer. This depends on both cell design and surfactant chemistry. (4) The froth layer must be separated from the pulp slurry before too many air bubbles coUapse and return ink particles to the pulp slurry. 

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