Prospectus

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PPP-1 Mass Transfer Efficiency – Different Physical Properties

Traditional Research Idea

Expected Benefit to Members: More reliable design with lower safety factors for distillations involving non-hydrocarbon chemicals. Present Situation and Proposed Research: Fundamental theories for modeling of mass transfer efficiency predict that an increase in surface tension should reduce efficiency. However, the chemical systems tested by FRI (mostly hydrocarbons) are such that the effect of surface tension cannot be distinguished from the effects of other physical properties. In order to predict efficiency reliably, the model should be based on data that allows the effects of the various physical properties to be determined independently. Efficiency data for a system whose physical properties relate differently from hydrocarbons will be collected at total reflux (L/V=1). Proposed Internals and Test System : Sieve trays and a packing Estimated Unit Time: Three weeks for each contacting device or six weeks total. Estimated Additional Costs (Beyond Unit Time): None Background and Discussion: Hydrocarbons have been preferred as test fluids by FRI because of cost, corrosion, health, safety, and environmental considerations. However, the relationship between the various physical properties of hydrocarbons is very similar, so that it is difficult to determine which property causes any particular observed effect. Data on systems with a different physical property correlation are needed for model improvement. Choosing an appropriate test system will be difficult, because many otherwise suitable systems contain chemicals that are toxic and/or corrosive. FRI does, however, have experience with some non-ideal systems such as propylene glycol and water.

PROSPECTUS

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