Prospectus

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PPP-3 Mass Transfer Efficiency – Steam Stripping of an Organic Less Volatile than Toluene Expected Benefit toMembers: More data on steam stripping of water will allow more reliable design with lower safety factors for liquid phase-controlled separations. Present Situation and Proposed Research: In 1988, FRI measured the efficiency of a sieve tray column in steam stripping toluene from water. The measured tray efficiencies were significantly different from those predicted by existing models, both FRI and the open literature. The data have been useful, not only in designing new strippers, but also in advising the EPA regarding the potential costs of mandated cleanup activities. The slope of the equilibrium line for stripping toluene from water at atmospheric conditions is about 2300. Consequently, the value of mV/L for these tests ranged from 120 to 2200. Virtually all of the rest of FRI’s efficiency data is at values of mV/L near 1.0. Models that successfully predict the efficiency of systems with mV/L = 1 do not predict the toluene stripping efficiency without including a function of mV/L; however, the mV/L for toluene stripping is so far removed from that of the other data that almost any arbitrary function will work. In order to obtain efficiency data over a more continuous range of mV/L, a compound less volatile than toluene will be stripped from water. The compound chosen should have an equilibrium line slope between 80 and 200. Traditional Research Idea

Proposed Internals and Test System: Sieve trays and a random packing. Estimated Unit Time: Four weeks per device, eight weeks’ total. Estimated Additional Costs (Beyond Unit Time): Unknown. Background and Discussion:

Compounds with the desired volatility would likely be partially soluble in water. This could lead to the possibility of foaming and/or the existence of two liquid phases in the tower. These phenomena are the subject of other proposals.

PROSPECTUS

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