The simplifying assumption adopted in Illes method for distillation states that vapor and liquid enthalpy-concentration curves are __________________?
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Answer: C. Both parallel and straight
Explanation
Illes method assumes enthalpy-concentration curves for vapor and liquid are both parallel and straight. This simplifying assumption linearizes the energy balance equations for multi-component distillation calculations. Assuming parallel and straight enthalpy curves greatly simplifies graphical design procedures for separation columns. Enthalpy-concentration diagrams are essential for analyzing non-ideal distillation systems with heat effects. Idealized assumptions like constant molar overflow or Illes simplifications make complex calculations manageable. Graphical methods rely on straight operating lines to determine theoretical stages efficiently.
Process design engineers use simplified graphical methods to estimate column sizing before running simulations. Understanding these assumptions helps identify when rigorous computer simulation models are strictly required. Applying Illes method speeds up preliminary feasibility studies for binary and ternary distillation units. Option A is incomplete because it ignores the crucial assumption that the curves are also straight. Option B is incomplete because it omits the requirement that the enthalpy curves must be parallel. Option D is incorrect because Illes method explicitly assumes both parallel and straight curve properties.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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