Steam batch distillation

STEAM - Multicomponent, Semi>Batch Steam Distillation... 

Figure 5.233. Schematic of the semi-batch steam distillation.

Bioremediation of Soil Particles 591 Spouted Bed Reactor Mixing Model 390 Steady-State, Two-Pass Heat Exchanger 515 Multicomponent, Semi-Batch Steam Distillation 508 Space-Time-Yield and Safety in a Semi-Continuous Reactor 365... 

T0431 IT Corporation, Batch Steam Distillation and Metals Extraction T0434 IT Corporation, Biological Polishing Treatment T0438 IT Corporation, Enhanced Natural Degradation (END)... 

T0431 IT Corporation, Batch Steam Distillation and Metals Extraction... 

The estimated treatment costs per ton, inclnding capital recovery, for the batch steam distillation are 299 to 393/ton and 266 to 350/ton at a 500-ton site and a 2500-ton site, respectively. 

Fig. 5.1 Automatic batch steam distillation unit (Interdyne).

Continuous steam stripping, in which the solvent-rich mixture is fed to the top of the column and steam is injected into the base, has a lower steam requirement than batch steam distillation. To reduce a toluene/involatile mixture from 0.9 to 0.1 mole fraction of solvent will theoretically require 0.315 kg steam/kg toluene, not allowing for the heating up of the mixture, compared with batch steam distillation at about 0.43 kg/kg. 

It is normal practice to undertake batch steam distillation at a constant steam input rate since the condenser is likely to be the rate-controlling component of the equipment. Thus the marginal cost per kg of the recovered solvent not only reflects its high steam requirement but also its high plant occupation time. 

Note We will see in Problem 9.E2 that batch steam distillation requires less steam than continuous steam distillation. 

During the batch steam distillation, the mole fraction of the volatile organics in the still varies, and thus, the still tenperature determined by Eq. (8 15) varies. Equation (9z23h) can be integrated numerically in steps. The total moles of water required is n plus the moles of water condensed to heat the feed and still pot, and to vaporize the volatile organics. 

During most of the batch operation, the mole fraction of the volatile organic is considerably higher than it is at the end of the batch. In continuous steam distillation the mole fraction of the volatile organic is always at its lowest value. Thus, batch steam distillation requires less steam for a given separation than continuous steam distillation. 

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