How does McCabe Thiele work?
How does McCabe Thiele work?
The reflux liquid travels down the column in the opposite direction to the rising vapor. The liquid “swaps” heavy components in the vapor for light components in the liquid, concentrating the light component in the vapor.
What is the equilibrium line in distillation?
The curved line is called the equilibrium line and describes the compositions of the liquid and vapour in equilibrium at some fixed pressure. This particular VLE plot shows a binary mixture that has a uniform vapour-liquid equilibrium that is relatively easy to separate.
What are the assumptions of McCabe Thiele method?
McCabe–Thiele method
- the molar heats of vaporization of the feed components are equal.
- for every mole of liquid vaporized, a mole of vapor is condensed.
- heat effects such as heats of solution are negligible.
What is the limitation of McCabe-Thiele method?
One of the main disadvantages of the McCabe-Thiele Method is that it is not very useful for analyzing the distillation of mixtures containing more than 2 components. However, the method is still useful as a teaching tool and a conceptual tool.
What is the operating line in a McCabe-Thiele diagram?
McCabe-Thiele diagram The upper operating line is a graphical representation of the vapor/liquid dynamics in each stage in the rectifying section of the column (above the feed stage), while the lower operating line represents the vapor/liquid dynamics in the stripping section of the column (below the feed stage).
How do I calculate the number of trays?
The number of theoretical trays can be calculated taking the logarithm of (6). Graphically, the number of theoretical trays can be determined by plotting the curve in Fig. 4 for a relative volatility of 1.07 (broken line).
What is the operating line in a McCabe Thiele diagram?
How do you calculate operating line?
liquid (L), it can be seen that the operating line is a simple y=mx+b equation. Therefore, with the point (xD,y1) and the slope (L/V), this operating line can be plotted.
How many trays do I need for a distillation column?
Towers concerned with the distillation of liquefied gases are only a few feet in diameter but may be up to 200 ft. in height. A tower used in the fractionation of crude oil may have from 16 to 28 trays, but one used in the fractionation (superfractionation) of liquefied gases may have 30–100 trays.
What is tray efficiency?
Tray efficiency measures the performance of a distillation tray or trays against the maximum theoretical performance. Similarly, a concept called Height Equivalent to Theoretical Plate (HETP) is used to measure the performance in a packed column.
How is the McCabe Thiele method used in distillation?
•The McCabe-Thiele method allows full control over reboiler duty, and it is not uncommon to first solve a problem assuming minimum reflux ratio. Results can be scaled to actual reflux ratio, typically R = 1.4*Rmin.
What was the purpose of the McCabe Thiele diagram?
The McCabe-Thiele diagram enabled decades of effective design and operational analysis of distillation columns, and has been used to teach several generations of chemical engineers to design and trouble- shoot distillation and other cascaded processes. Simplifi ed methods such as McCabe-Thiele are rarely used today for detailed design.
How to calculate the number of stages in binary distillation?
Binary Distillation McCabe Thiele Diagram Binary distillation using Mc-Cabe Thiele Diagram calculates total number of stages, Feed point required to separate a binary mixture with given Relative Volatility, Reflux Ratio, Feed, Bottom, Distillate Mol Fraction CheCalc
What was the CMO of McCabe and Thiele?
M ore than 80 years ago, McCabe and Thiele developed a creative graphical solution tech- nique based on Lewis’s assumption of constant molal overfl ow (CMO) for the rational design of distilla- tion columns (1).