Series connections on underflow

This system may or may not use intermediate pumps. If it does not, the additional backpressure on the underflows of stages 1 and 2 has to be compensated for by throttling the overflow orifices of these stages. Otherwise, the overflow rates would be much greater than for the same cyclones operated under balanced conditions. 

The last conclusion is qualitatively the same as that for the overflow series in that they both sharpen the cut. Even quantitatively, when using a symmetrical sharpness index derived from the reduced grade efficiency curves, one obtains very much the same results for the underflow series as contained in 

The overflow series gives a steeper G (x) in the coarser part, above the cut size, and this means that it gives a cleaner fine product than the underflow series. In the fines region, however, it is less steep and thus misplaces more of 

A special case of this separator series is the countercurrent washing system and this is capable of thickening at the same time. In this arrangement, as 

In washing, thickening and recovery applications we try to set the cut size of the system below the finest particle size present in the feed, so that any loss of particles into the system overflow is minimized. The problem is that, as was shown in the previous section, the underflow series that is needed for 

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