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Feed Condition (q-line) Calculation

Calculates the q-line parameters (liquid fraction, slope, intercept) for McCabe-Thiele distillation analysis based on feed composition and vapor fraction.

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1. Define Input Parameters

2. Engineering Output

Liquid Fraction (q-factor) (q)
- dimensionless
q-line Slope (m)
- dimensionless
q-line Intercept (c)
- dimensionless

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Context & Assumptions

The q-line defines the thermal condition of the feed in a binary distillation column, determining the intersection of rectifying and stripping operating lines on a McCabe-Thiele diagram. This calculation uses the feed composition and vapor fraction to compute the liquid fraction (q), slope, and intercept of the q-line.

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Review the step-by-step derivations, typical industrial limits, and scale-up rules.

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