Dear Mohammad,

Roughing is the first stage of flotation which produces a rougher concentrate. The objective is to remove the maximum amount of the valuable mineral at as coarse a particle size as practical.The finer an ore is ground, the greater the energy that is required, so it makes sense to fine grind only those particles that need fine grinding. Complete liberation is not required for rougher flotation, only sufficient liberation to release enough gangue from the valuable mineral to get a high recovery. The primary objective of roughing is to recover as much of the valuable minerals as possible, with less emphasis on the quality of the concentrate produced. The rougher flotation step is often followed by a scavenger flotation step that is applied to the rougher tailings. The objective is to recover any of the target minerals that were not recovered during the initial roughing stage. This might be achieved by changing the flotation conditions to make them more rigorous than the initial roughing, or there might be some secondary grinding to provide further liberation.

The concentrate from the rougher scavengers could be returned to the rougher feed for refloating.

From this text we can conclude that a variety of parameters can decrease the metal (molybdenum) in the rougher and scavenger cells.

For example the following shows how we can increase or decrease the metal in these cells using the equations depicted below

(a) Ratio of Concentration, the weight of the feed relative to the weight of the concentrate, The Ratio of Concentration is F/C, where F is the total weight of the feed and C is the total weight of the concentrate. One limitation with this calculation is that it uses the weights of the feed and concentrate. While this data is available in laboratory experiments, in the plant it is likely that the ore is not weighed and only assays will be available. However, it is possible to express the ratio of concentration in terms of ore assays. Starting with the mass balance equations, and the definition of the ratio of concentration:

F = C + T, Ff = Cc + Tt, Ratio of Concentration = F/C

where F, C, and T are the % weights of the feed, concentrate, and tailings, respectively; and f, c, and t are the assays of the feed, concentrate, and tailings. We now need to eliminate T from these equations so that we can solve for F/C:

Ff = Cc + Tt, and multiplying (F = C + T) by t gives us:

Ft = Ct + Tt, so subtracting this equation from the previous eliminates T and gives:

F(f - t) = C(c - t), and rearranging produces the equation for the ratio of concentration:

F/C = (c – t)/(f – t)

(b) % Metal Recovery, or percentage of the metal in the original feed that is recovered in the concentrate. This can be calculated using weights and assays, as (Cc)/(Ff)·100. Or, since C/F = (f – t)/(c – t), the % Metal Recovery can be calculated from assays alone using 100(c/f)(f – t)/(c –t).

(c) % Metal Loss is the opposite of the % Metal Recovery, and represents the material lost to the tailings. It can be calculated simply by subtracting the % Metal Recovery from 100%.

(d) % Weight Recovery is essentially the inverse of the ratio of concentration, and equals 100·C/F = 100·(f – t)/(c – t).

(e) Enrichment Ratio is calculated directly from assays as c/f, weights are not involved in the calculation.

For the effect of other parameters see attached file.

Hoping this will be helpful,

Rafik

hi dear abhishek raj,

thank for your answer to my question, can you give me one solution to decease molybdenum in tail when clay increase in the feed. you know that clay make more problem in the flotation treatment.  

beat regards,

Mohammad jafari

hi dear Rafik

thank for your answer to my question, i am studying your solution but  a cant see one solution which you had been used to decrease clay interaction in the molybdenum flotation.

 can you give me one solution to decease molybdenum in tail when clay increase in the feed. you know that clay make more problem in the flotation treatment. clay have surface electric pot, and its size is like fine particles and this properties of the clay particle make more problem in the molybdenum flotation system  

beat regards,

Mohammad jafari

Dear Mohammad,

You should play with the parameters of this equation:

F/C = (c – t)/(f – t)

Rafik