Overflow entrainment into

The reduced separation efficiency (Eq. 5), also called centrifugal efficiency, is used for separators with Rf > 0, and gives the separation efficiency taking into account only those particles that will be separated or not due to the centrifugal field intensity. Hence, E does not consider the particles that are separated due to entrainment in the overflow stream. 

The modification involved the rerouting of the discharge water from the barometric condenser. Rather than being discharged into a chemical sewer via a sump, the water stream had been routed to a hopper that allowed the entrained heat transfer fluid droplets to drop out of solution md be recovered. Decontaminated water overflowed to the chemical sewer (see Figure 2-17). 

The solvent and steam vapors from the stripper are condensed together and go to a solvent-water separator, where the condensed liquids separate into lightweight hexane floating on the heavier water. The hexane overflows the top of the solvent-water separator and goes to the solvent work tank. Water, with some entrained hexane, syphons from the bottom of the solvent-water separator and goes to a water... 

I-beam interference can be just as troublesome in the space above a chimney tray. In one case history contributed by D. W. Reay (334), this interference is believed to have led to severe vapor maldistribution in a refinery vacuum tower (Fig. 8.66). The maldistributed vapor profile was displayed as a carbon deposit on the siuTace of the bottom packing. The deposit formed an annular ring about 5 ft wide that extended about 1 in into the bed. In that case, liquid was known to overflow the chimneys for several months because of an incorrect location of level tappings. This overflow caused liquid entrainment. Some entrained droplets ultimately carbonized on the base of the bed. Had the vapor profile been uniform, entrainment (and therefore deposit laydown) would have been more uniform. It is believed that vapor from the side chimneys was blocked by the beams and preferentially ascended around the periphery. If liquid overflow (down the risers) had been uneven, the maldistribution could have been further aggravated. 

Feeder overflows only when solids are being conveying into the hopper FRI is small/ air entrained with particles entering the hopper. 

The equilibrium data for leaching must be obtained experimentally since it will depend on the exact nature of the solids, which may change from source to source. If there is no entrainment, the overflow (extract) stream will often contain no inert solids (diluent). However, the raffinate stream will contain solvent. Test data for the extraction of oil from meal with benzene are given in Table 14-2 tPrabhudesai. 1997L In these data, inert solids are not extracted into the benzene. The data are plotted on a triangular... 

The flue gas exits from the bed through the freeboard, where oxidation (particularly of volatiles) is completed and the larger solid particles entrained in the flue gas fall back into the bed. Due to attrition or burnout, ash is usually reduced to a sufficiently small size that it exits the combustor with the flue gas. The bed material that accumulates is typically removed from the bed by an overflow drain, thus taking advantage of the bed s fluid characteristics. 

Duration and rate of transfer into the tank. The quantity of petrol that overflowed Tank 912 at Buncefieid from initial overflow to ignition was approximately 300 tonnes. If the transfer rate or overflow duration is estimated to be significantly different to that at Buncefieid, then this may affect the formation and size of the cloud. An estimate of cloud generation could be made based on modelling such as the HSL entrainment calculator and a 2 m cloud height (for further information see Appendix 1). 

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