This document discusses distillation of binary mixtures. It begins by defining distillation as a process that separates a feed mixture into multiple products, often an overhead distillate and a bottoms product, using the differences in volatility between components. The key design factors for distillation include feed composition, desired separation, operating pressure, reflux ratio, number of stages, condenser/reboiler type, and column internals. Vapor-liquid equilibrium concepts like relative volatility and Raoult's law determine the feasibility of separation. Single-stage processes like flash distillation, simple batch distillation, and steam distillation are also introduced.
1) Distillation is a method used to separate components of a liquid solution based on differences in how the components distribute between the vapor and liquid phases when heated to their boiling points.
2) Raoult's law describes vapor-liquid equilibrium for ideal solutions, relating the partial pressure of a component in vapor phase to its mole fraction in the liquid phase. Boiling point diagrams can be constructed using vapor pressure data.
3) Equilibrium or flash distillation involves heating a liquid mixture to partially vaporize it in a single stage, separating the vapor and liquid which approach equilibrium compositions.
The McCabe-Thiele method is a graphical technique for determining the minimum number of stages required for distillation. It involves plotting the equilibrium relationship between liquid and vapor phases on a diagram and constructing operating lines to represent the mass balances in the rectifying and stripping sections. Intersections between the lines indicate the number of ideal stages. The method was developed in 1925 and remains useful for preliminary column design. Key considerations include the feed composition and enthalpy, reflux ratio, and use of partial condensers or reboilers.
This booklet contains mainly the concepts of distillation which are required by the plant designers as well as plant operational teams. This will help readers to get more of insight of distillation column understanding.
This experiment aimed to determine how concentration affects the weight and volume of cake obtained from a plate and frame filter press, as well as the length of time needed to obtain a certain volume of filtrate. The results showed that as concentration increased, the time required to collect a set volume of filtrate also increased. A linear relationship was observed between volume of filtrate and time per volume of filtrate, with an r-squared value of 0.95, indicating these variables increased proportionally. Sources of error included possible equipment defects and variability in cake weights.
The document discusses azeotropic and steam distillation. It defines azeotropes as mixtures that have the same composition in both the liquid and vapor phases, preventing separation through simple distillation. There are two types: minimum boiling and maximum boiling azeotropes. Methods to separate azeotropes include pressure swing distillation, azeotropic distillation using an entrainer, and steam distillation for heat-sensitive compounds. Azeotropic distillation works by forming a new low-boiling azeotrope with the entrainer, then separating the components in a decanter. Steam distillation uses water vapor to carry compounds over at lower temperatures than simple distillation
The document describes continuous flash distillation. Flash distillation involves partially vaporizing a liquid mixture, allowing the vapor and liquid to reach equilibrium, and then withdrawing them separately. Material balances are used to model flash distillation. The flash distillation process is commonly used in the petroleum industry to separate petroleum fractions by heating the fluid and "flashing" it into an overheated vapor stream and residual liquid stream.
This document provides information about an advanced chemical engineering thermodynamics course, including:
1) The course covers basic definitions, concepts, relationships for pure components and mixtures including pvT relationships and thermodynamic property relationships.
2) Relevant textbooks are listed for reference.
3) Methods for determining pvT properties of pure components and mixtures are discussed, including experimental determination, databases, equations of state, and process simulators.
4) The Lydersen and Pitzer methods for corresponding states are summarized, which use critical compressibility factor and acentric factor respectively as third parameters to determine compressibility factor from reduced temperature and pressure.
1) Conversion and reactor sizing for different reactor types such as batch, CSTR, PFR and reactors in series are discussed. Key equations for calculating conversion and sizing reactors given reaction rate data are presented.
2) Examples are provided to calculate the volume of a CSTR and PFR needed to achieve 80% conversion of a reactant based on rate data, and to compare the required volumes between reactor types.
3) For an isothermal reaction, a CSTR typically requires a larger volume than a PFR to achieve the same conversion due to operating at the lowest reaction rate throughout the reactor.
1) Distillation is a method used to separate components of a liquid solution based on differences in how the components distribute between the vapor and liquid phases when heated to their boiling points.
2) Raoult's law describes vapor-liquid equilibrium for ideal solutions, relating the partial pressure of a component in vapor phase to its mole fraction in the liquid phase. Boiling point diagrams can be constructed using vapor pressure data.
3) Equilibrium or flash distillation involves heating a liquid mixture to partially vaporize it in a single stage, separating the vapor and liquid which approach equilibrium compositions.
The McCabe-Thiele method is a graphical technique for determining the minimum number of stages required for distillation. It involves plotting the equilibrium relationship between liquid and vapor phases on a diagram and constructing operating lines to represent the mass balances in the rectifying and stripping sections. Intersections between the lines indicate the number of ideal stages. The method was developed in 1925 and remains useful for preliminary column design. Key considerations include the feed composition and enthalpy, reflux ratio, and use of partial condensers or reboilers.
This booklet contains mainly the concepts of distillation which are required by the plant designers as well as plant operational teams. This will help readers to get more of insight of distillation column understanding.
This experiment aimed to determine how concentration affects the weight and volume of cake obtained from a plate and frame filter press, as well as the length of time needed to obtain a certain volume of filtrate. The results showed that as concentration increased, the time required to collect a set volume of filtrate also increased. A linear relationship was observed between volume of filtrate and time per volume of filtrate, with an r-squared value of 0.95, indicating these variables increased proportionally. Sources of error included possible equipment defects and variability in cake weights.
The document discusses azeotropic and steam distillation. It defines azeotropes as mixtures that have the same composition in both the liquid and vapor phases, preventing separation through simple distillation. There are two types: minimum boiling and maximum boiling azeotropes. Methods to separate azeotropes include pressure swing distillation, azeotropic distillation using an entrainer, and steam distillation for heat-sensitive compounds. Azeotropic distillation works by forming a new low-boiling azeotrope with the entrainer, then separating the components in a decanter. Steam distillation uses water vapor to carry compounds over at lower temperatures than simple distillation
The document describes continuous flash distillation. Flash distillation involves partially vaporizing a liquid mixture, allowing the vapor and liquid to reach equilibrium, and then withdrawing them separately. Material balances are used to model flash distillation. The flash distillation process is commonly used in the petroleum industry to separate petroleum fractions by heating the fluid and "flashing" it into an overheated vapor stream and residual liquid stream.
This document provides information about an advanced chemical engineering thermodynamics course, including:
1) The course covers basic definitions, concepts, relationships for pure components and mixtures including pvT relationships and thermodynamic property relationships.
2) Relevant textbooks are listed for reference.
3) Methods for determining pvT properties of pure components and mixtures are discussed, including experimental determination, databases, equations of state, and process simulators.
4) The Lydersen and Pitzer methods for corresponding states are summarized, which use critical compressibility factor and acentric factor respectively as third parameters to determine compressibility factor from reduced temperature and pressure.
1) Conversion and reactor sizing for different reactor types such as batch, CSTR, PFR and reactors in series are discussed. Key equations for calculating conversion and sizing reactors given reaction rate data are presented.
2) Examples are provided to calculate the volume of a CSTR and PFR needed to achieve 80% conversion of a reactant based on rate data, and to compare the required volumes between reactor types.
3) For an isothermal reaction, a CSTR typically requires a larger volume than a PFR to achieve the same conversion due to operating at the lowest reaction rate throughout the reactor.
The experiment examined pressure drop across a packed column as a function of air and water flow rates. Pressure drop increased with higher flow rates of both air and water. The relationship between log pressure drop and log air flow rate was plotted, showing they follow the same trend as theoretical predictions. Pressure drop rose sharply before a "flooding point" where liquid accumulated and filled the column.
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project (https://www.spire2030.eu/impress).
Section: Distillation
Subject: 2.1 Material balances
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project (https://www.spire2030.eu/impress).
Section: Distillation
Subject: 1.2 Flash distillation.
Excess gibbs free energy models,MARGULES EQUATION
,REDLICH-KISTER EQUATION,VAN LAAR EQUATION
,WILSON AND “NRTL” EQUATION
,UNIversal QUAsi Chemical equation
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project.
Section: Distillation
Subject: 0.3 Basic concepts of distillation
Feed conditions in distillation column with respect to feed plate and refluxIhsan Wassan
This document discusses feed conditions in distillation columns with respect to the feed plate and reflux. It defines key terms like distillation, relative volatility, and reflux. It explains that the condition of the feed stream determines the relation between flows above and below the feed plate. The amount of saturated liquid versus vapor in the feed is quantified by a variable q. Feed can be saturated liquid/vapor or a mixture, determining the slope of the q-line. Feed plates help separate mixtures, and more reflux improves separation efficiency, allowing fewer plates for a given separation. Total reflux passes vapor and liquid without product removal, while minimum reflux is the lowest ratio enabling separation with infinite plates.
1. The document discusses vapor-liquid equilibrium (VLE) and some simple models for calculating VLE, including Raoult's law and Henry's law.
2. Raoult's law assumes an ideal gas in the vapor phase and an ideal solution in the liquid phase. Henry's law is applicable for very dilute solutions and low pressures where the vapor can be treated as an ideal gas.
3. Examples are provided to demonstrate calculating bubble point, dew point, and equilibrium conditions using these models. Modified Raoult's law is also introduced, which accounts for non-ideality in the liquid phase using activity coefficients.
batch distillation, multi stage batch distillationKarnav Rana
This document discusses batch distillation. It begins by contrasting batch and continuous distillation, noting that batch distillation is useful when small amounts of products with varying compositions are needed. The key difference is that batch distillation involves no continuous feed or product withdrawal. Rayleigh's equation is then derived and explained, providing a critical third equation to solve batch distillation problems using material balances. Graphical and numerical integration techniques are presented for using Rayleigh's equation to determine unknown values like the final liquid amount.
Introduction to multicomponent distillationSujeet TAMBE
This document provides an introduction and overview of multicomponent distillation processes. It discusses key concepts like key components, distributed vs. undistributed components, and challenges in designing multicomponent distillation columns compared to binary systems. The document then outlines the steps of the Fenske-Underwood-Gilliland short cut design method for solving multicomponent distillation problems, including calculating the minimum number of stages, minimum reflux ratio, actual number of stages, and feed stage location.
This document summarizes various distillation techniques including differential distillation, flash vaporization, continuous rectification, and determining the ideal number of plates. It discusses mass balances, operating lines, reflux ratios, and how changing the number of plates and reflux ratio influences distillation column design and performance. Key aspects covered include equilibrium relationships, material flowing between plates, determining flow rates, and using diagrams to analyze fractionation.
The document discusses the McCabe Thiele method for analyzing distillation columns. It begins by defining the rectifying section operating line (ROL) equation as yn+1 = (R/(R+1))xn + (1/(R+1))xD, where R is the reflux ratio.
It then explains that the McCabe Thiele method uses equilibrium curves and operating lines on a graphical diagram to determine the minimum number of theoretical stages needed for a given separation. The method involves constructing triangles between the equilibrium curve and operating line, with each triangle representing one theoretical tray.
I found no good source for extractive distillation on the internet.So i decided to make one myself.This ppt discusses about the technology,its working and benefits.It compares extractive distillation side by side to azeotropic distillation and counts the advantages.
This document discusses enthalpy balances in distillation. It defines enthalpy and provides enthalpy-concentration diagrams. Equations for total and individual enthalpy balances are presented for the rectifying and stripping sections. The document describes how to solve the equations using an iterative approach with enthalpy data. It also discusses how to calculate the feed enthalpy parameter q using enthalpy values. An example problem calculates q for a benzene-toluene mixture.
This document discusses vapor/liquid equilibrium (VLE) and provides models for predicting VLE using simple models like Raoult's law and Henry's law. It defines key terms like mass fraction, mole fraction, molar concentration. Duhem's theorem is introduced which states that the equilibrium state is determined by fixing any two independent variables for a closed system. Simple calculations are shown for using Raoult's law to determine the bubble point and dew point temperatures and pressures of a binary system from its phase compositions or known temperature. P-x-y and T-x-y diagrams are used to illustrate the VLE behavior between the phases.
The document discusses the basics of distillation column design. It explains that column design begins with building a model of how the chemicals will separate based on their properties like vapor pressure and boiling point. The model is used to identify the minimum number of theoretical stages or trays needed for effective separation. Key design considerations include parameters like flood ratio, weeping point, efficiency, reflux ratio, and HETP. The document also outlines the basic components of a distillation column like the condenser, reboiler, and trays or packing material. It notes the inputs needed from the client and outputs provided by an expert column designer.
This document provides an overview of applied fluid dynamics for agitation and mixing. It discusses key topics such as:
- Common agitation and mixing equipment like impellers, tanks, baffles, and their design considerations.
- The differences between agitation and mixing, and how each promotes mass and heat transfer.
- Design equations for sizing equipment, determining power requirements, and calculating time of mixing using concepts like power number and mixing time factors.
- The use of computational fluid dynamics software to model agitation and mixing systems.
This experiment aims to discover the effect of initial concentration and initial height on sedimentation characteristics of calcium carbonate particles suspended in water. Data was collected for calcium carbonate suspensions at different concentrations (2-10%) and initial heights, measuring the settling velocity over time. The results show an inverse relationship between concentration and settling velocity, with higher concentrations settling more slowly. Higher initial heights also resulted in higher settling velocities compared to the same concentration at a lower initial height. Graphs of settling velocity versus limiting concentration were similar for all cases tested.
This document discusses reflux ratios in distillation columns. It defines total, minimum, and optimum reflux ratios. Total reflux uses all overhead vapor as reflux, allowing calculation of minimum required plates. Minimum reflux is the maximum ratio requiring infinite plates for desired separation. Optimum reflux minimizes total costs by balancing fixed costs that decrease with higher reflux against increasing operating costs.
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project.
Section: Distillation
Subject: 1.1 Vapor Liquid Equilibrium
Distillation is a common separation technique that relies on differences in boiling points. It can be energy intensive and account for over 50% of operating costs. There are various types of distillation columns, including batch vs continuous, binary vs multi-component, and tray vs packed columns. Key components include a shell, internals, reboiler, condenser, and reflux drum. McCabe-Thiele design uses vapor-liquid equilibrium data to determine the theoretical number of stages needed for separation.
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize components with lower boiling points and then condensing the vapors. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to lower boiling points of heat-sensitive materials. Distillation is an important separation technique used in pharmacy, chemistry, and other fields.
The experiment examined pressure drop across a packed column as a function of air and water flow rates. Pressure drop increased with higher flow rates of both air and water. The relationship between log pressure drop and log air flow rate was plotted, showing they follow the same trend as theoretical predictions. Pressure drop rose sharply before a "flooding point" where liquid accumulated and filled the column.
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project (https://www.spire2030.eu/impress).
Section: Distillation
Subject: 2.1 Material balances
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project (https://www.spire2030.eu/impress).
Section: Distillation
Subject: 1.2 Flash distillation.
Excess gibbs free energy models,MARGULES EQUATION
,REDLICH-KISTER EQUATION,VAN LAAR EQUATION
,WILSON AND “NRTL” EQUATION
,UNIversal QUAsi Chemical equation
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project.
Section: Distillation
Subject: 0.3 Basic concepts of distillation
Feed conditions in distillation column with respect to feed plate and refluxIhsan Wassan
This document discusses feed conditions in distillation columns with respect to the feed plate and reflux. It defines key terms like distillation, relative volatility, and reflux. It explains that the condition of the feed stream determines the relation between flows above and below the feed plate. The amount of saturated liquid versus vapor in the feed is quantified by a variable q. Feed can be saturated liquid/vapor or a mixture, determining the slope of the q-line. Feed plates help separate mixtures, and more reflux improves separation efficiency, allowing fewer plates for a given separation. Total reflux passes vapor and liquid without product removal, while minimum reflux is the lowest ratio enabling separation with infinite plates.
1. The document discusses vapor-liquid equilibrium (VLE) and some simple models for calculating VLE, including Raoult's law and Henry's law.
2. Raoult's law assumes an ideal gas in the vapor phase and an ideal solution in the liquid phase. Henry's law is applicable for very dilute solutions and low pressures where the vapor can be treated as an ideal gas.
3. Examples are provided to demonstrate calculating bubble point, dew point, and equilibrium conditions using these models. Modified Raoult's law is also introduced, which accounts for non-ideality in the liquid phase using activity coefficients.
batch distillation, multi stage batch distillationKarnav Rana
This document discusses batch distillation. It begins by contrasting batch and continuous distillation, noting that batch distillation is useful when small amounts of products with varying compositions are needed. The key difference is that batch distillation involves no continuous feed or product withdrawal. Rayleigh's equation is then derived and explained, providing a critical third equation to solve batch distillation problems using material balances. Graphical and numerical integration techniques are presented for using Rayleigh's equation to determine unknown values like the final liquid amount.
Introduction to multicomponent distillationSujeet TAMBE
This document provides an introduction and overview of multicomponent distillation processes. It discusses key concepts like key components, distributed vs. undistributed components, and challenges in designing multicomponent distillation columns compared to binary systems. The document then outlines the steps of the Fenske-Underwood-Gilliland short cut design method for solving multicomponent distillation problems, including calculating the minimum number of stages, minimum reflux ratio, actual number of stages, and feed stage location.
This document summarizes various distillation techniques including differential distillation, flash vaporization, continuous rectification, and determining the ideal number of plates. It discusses mass balances, operating lines, reflux ratios, and how changing the number of plates and reflux ratio influences distillation column design and performance. Key aspects covered include equilibrium relationships, material flowing between plates, determining flow rates, and using diagrams to analyze fractionation.
The document discusses the McCabe Thiele method for analyzing distillation columns. It begins by defining the rectifying section operating line (ROL) equation as yn+1 = (R/(R+1))xn + (1/(R+1))xD, where R is the reflux ratio.
It then explains that the McCabe Thiele method uses equilibrium curves and operating lines on a graphical diagram to determine the minimum number of theoretical stages needed for a given separation. The method involves constructing triangles between the equilibrium curve and operating line, with each triangle representing one theoretical tray.
I found no good source for extractive distillation on the internet.So i decided to make one myself.This ppt discusses about the technology,its working and benefits.It compares extractive distillation side by side to azeotropic distillation and counts the advantages.
This document discusses enthalpy balances in distillation. It defines enthalpy and provides enthalpy-concentration diagrams. Equations for total and individual enthalpy balances are presented for the rectifying and stripping sections. The document describes how to solve the equations using an iterative approach with enthalpy data. It also discusses how to calculate the feed enthalpy parameter q using enthalpy values. An example problem calculates q for a benzene-toluene mixture.
This document discusses vapor/liquid equilibrium (VLE) and provides models for predicting VLE using simple models like Raoult's law and Henry's law. It defines key terms like mass fraction, mole fraction, molar concentration. Duhem's theorem is introduced which states that the equilibrium state is determined by fixing any two independent variables for a closed system. Simple calculations are shown for using Raoult's law to determine the bubble point and dew point temperatures and pressures of a binary system from its phase compositions or known temperature. P-x-y and T-x-y diagrams are used to illustrate the VLE behavior between the phases.
The document discusses the basics of distillation column design. It explains that column design begins with building a model of how the chemicals will separate based on their properties like vapor pressure and boiling point. The model is used to identify the minimum number of theoretical stages or trays needed for effective separation. Key design considerations include parameters like flood ratio, weeping point, efficiency, reflux ratio, and HETP. The document also outlines the basic components of a distillation column like the condenser, reboiler, and trays or packing material. It notes the inputs needed from the client and outputs provided by an expert column designer.
This document provides an overview of applied fluid dynamics for agitation and mixing. It discusses key topics such as:
- Common agitation and mixing equipment like impellers, tanks, baffles, and their design considerations.
- The differences between agitation and mixing, and how each promotes mass and heat transfer.
- Design equations for sizing equipment, determining power requirements, and calculating time of mixing using concepts like power number and mixing time factors.
- The use of computational fluid dynamics software to model agitation and mixing systems.
This experiment aims to discover the effect of initial concentration and initial height on sedimentation characteristics of calcium carbonate particles suspended in water. Data was collected for calcium carbonate suspensions at different concentrations (2-10%) and initial heights, measuring the settling velocity over time. The results show an inverse relationship between concentration and settling velocity, with higher concentrations settling more slowly. Higher initial heights also resulted in higher settling velocities compared to the same concentration at a lower initial height. Graphs of settling velocity versus limiting concentration were similar for all cases tested.
This document discusses reflux ratios in distillation columns. It defines total, minimum, and optimum reflux ratios. Total reflux uses all overhead vapor as reflux, allowing calculation of minimum required plates. Minimum reflux is the maximum ratio requiring infinite plates for desired separation. Optimum reflux minimizes total costs by balancing fixed costs that decrease with higher reflux against increasing operating costs.
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project.
Section: Distillation
Subject: 1.1 Vapor Liquid Equilibrium
Distillation is a common separation technique that relies on differences in boiling points. It can be energy intensive and account for over 50% of operating costs. There are various types of distillation columns, including batch vs continuous, binary vs multi-component, and tray vs packed columns. Key components include a shell, internals, reboiler, condenser, and reflux drum. McCabe-Thiele design uses vapor-liquid equilibrium data to determine the theoretical number of stages needed for separation.
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize components with lower boiling points and then condensing the vapors. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to lower boiling points of heat-sensitive materials. Distillation is an important separation technique used in pharmacy, chemistry, and other fields.
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize components with lower boiling points and then condensing the vapors. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to lower boiling points of heat-sensitive materials. Distillation is an important separation technique used in pharmacy, chemistry, and other fields.
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize more volatile components, which are then condensed and collected. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to reduce boiling points of heat-sensitive materials. Distillation is used in pharmacy and chemistry to extract and purify substances.
Distillation is a physical separation process that separates mixtures based on differences in their boiling points. It involves heating a mixture until it vaporizes, cooling the vapors until they condense, and collecting the purified liquid fractions. Simple distillation uses one equilibrium stage while fractional distillation uses multiple equilibrium stages to improve separation efficiency. Raoult's law describes vapor pressures in ideal mixtures but some mixtures form azeotropes that cannot be separated by distillation alone.
Solvent extraction,Leaching, gas absorption equipmentVinithaKannan1
Solvent extraction, leaching, and gas absorption are separation processes used in food processing. Solvent extraction uses immiscible liquids to separate solutes. Liquid-liquid extraction uses mixing tanks or columns, while solid-liquid extraction uses static beds. Gas absorption uses agitated vessels or multistage columns like packed towers to transfer gases into liquids. Equipment is designed using equilibrium models and mass transfer principles to maximize separation efficiency.
A fractional distillation apparatus utilizes multiple vaporization-condensation cycles through a fractionating column to more efficiently separate components compared to simple distillation. For a mixture of 80% toluene and 20% benzene, simple distillation would result in a vapor enriched to 55% toluene and 45% benzene. However, with fractional distillation using multiple theoretical plates, the composition after each cycle becomes more enriched in the lower boiling benzene. After 7 cycles, the distillate collected would be 99% pure benzene, demonstrating the improved separation efficiency of fractional distillation over simple distillation.
This document discusses fractional distillation and the boiling point of liquids. It explains that the boiling point is the temperature at which the vapor pressure of a liquid equals the surrounding pressure. For pure liquids, the boiling point remains constant as boiling occurs. However, for liquid mixtures, the boiling temperature rises over time as the more volatile component evaporates first. Fractional distillation takes advantage of vapor enrichment to separate mixtures based on differences in boiling points. Multiple vaporization-condensation steps in a distillation column allow for near pure separation of components.
This document provides an overview of properties of pure substances and the steam power cycle. It begins by defining a pure substance and describing the three phases of matter: liquid, gas and vapor. It then explains the phase change process that water undergoes from compressed liquid to superheated vapor. Property diagrams like P-V, P-T, T-V and h-s diagrams are introduced to illustrate the thermodynamic properties. The ideal Rankine cycle and its processes are described along with methods to improve cycle efficiency like regeneration and reheat. Finally, it discusses other cycles like binary vapor cycles and combined cycles.
This document provides an overview of properties of pure substances and steam power cycles. It defines a pure substance as having a fixed chemical composition and discusses the three phases of matter. It describes the phase change process that water undergoes from compressed liquid to superheated vapor. Key concepts covered include saturation temperature and pressure, property diagrams, use of steam tables and Mollier charts, dryness fraction determination methods, and the ideal Rankine cycle. Variations of the Rankine cycle like reheat, regenerative, binary vapor, and combined cycles are also summarized.
This PowerPoint presentation discusses various types of distillation processes including simple distillation, fractional distillation, flash distillation, azeotropic distillation, and steam distillation. It explains the basic principles and components of distillation, differences between continuous and batch distillation, factors that influence column efficiency, and challenges with separating azeotropic mixtures. Key concepts covered include Raoult's law, distillation curves, reflux ratios, and minimum and maximum boiling azeotropes.
continuous distillation with rectification process and its working principal with diagram and also its use in industrial applications.
design and operations explained.
The presentation describes various aspects of the distillation process involved in pharmaceutical industry. It includes definition, applications and types of distillation process. It focuses on simple distillation, fractional distillation, distillation under reduced pressure, steam distillation, molecular distillation vacuum distillation. It also explains boiling point composition curves, Raoult's law, Dalton's law, real solutions and ideal solutions.
The document describes procedures for simple and fractional distillation. Simple distillation allows separation of compounds with a boiling point difference of over 40-50°C, while fractional distillation using a fractionating column can separate compounds that boil within 50°C of each other. The document outlines the setup and procedure for simple distillation of an acetone-water mixture, including recording temperature and volume collected. Fractional distillation of the same mixture is then described using the fractionating column to achieve better separation.
This document discusses different types of distillation processes including simple distillation and fractional distillation. Simple distillation involves a single vaporization and condensation cycle that produces an impure distillate. Fractional distillation uses a fractionating column containing packing materials between the distillation flask and head. This allows for multiple vaporization and condensation cycles, improving separation of components in the mixture. The document describes components of distillation columns like trays, packings, reboilers and condensers and how they facilitate fractional distillation.
Continuous distillation columns - Characteristics at different operating cond...Noaman Ahmed
This document discusses different operating conditions of continuous distillation columns under total reflux, including four types of total reflux. It describes total reflux, where no distillate or bottom products leave the column. It also discusses the material balance equation and introduces the Θ method and Newton Raphson method for determining column specifications under Type 1 total reflux conditions, where distillate and bottom rates are finite as reflux ratio approaches infinity. The document provides an example application of the Θ method and compares it to the Newton Raphson method.
Full Distillation technique where you find about various terminologies, its principle in which raolt's law and henry's law, assembly, classification. Distillation apparatus with their principle, advantages and disadvantages and detailed abour steam distillation and azeotropic distillation.
Thermody Properties of Pure Substance (1).pptethiouniverse
- A pure substance has a fixed chemical composition regardless of phase. Water can exist as ice, liquid water, or water vapor while maintaining the same molecular formula.
- A pure substance can change between solid, liquid, and gas phases depending on temperature and pressure. The phase change occurs at the saturation temperature and pressure.
- During a phase change, energy is absorbed or released in the form of latent heat. The latent heat of fusion is released during freezing and the latent heat of vaporization is released during condensation.
Distillation is a process that separates liquids in a mixture based on differences in their boiling points. It works by heating the mixture to vaporize components, then cooling to condense them. There are several types including simple, flash, and rectification distillation. Rectification uses a fractionating column with trays to continuously refine the vapor into pure products. Key factors that determine separation include relative volatility and vapor-liquid equilibrium curves. Distillation is widely used in oil refining and other industrial separations.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Design and optimization of ion propulsion dronebjmsejournal
Electric propulsion technology is widely used in many kinds of vehicles in recent years, and aircrafts are no exception. Technically, UAVs are electrically propelled but tend to produce a significant amount of noise and vibrations. Ion propulsion technology for drones is a potential solution to this problem. Ion propulsion technology is proven to be feasible in the earth’s atmosphere. The study presented in this article shows the design of EHD thrusters and power supply for ion propulsion drones along with performance optimization of high-voltage power supply for endurance in earth’s atmosphere.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
3. BITS Pilani, Pilani Campus
• A feed mixture of two or more components is separated
into two or more products
• often limited to, an overhead distillate and
• a bottoms product
• Most often, the feed is a liquid or a vapor–liquid mixture
• The bottoms product is almost always a liquid
• The distillate may be a liquid, a vapor, or both
• The separation requires that
• a second phase be formed so that both liquid and vapor are
present and can make contact while flowing counter currently to
each other in a trayed or packed column
Distillation (Fractionation)
4. BITS Pilani, Pilani Campus
• components have different volatilities so that they partition
between phases to different extents, and
• the two phases are separable by gravity or mechanical means
• Distillation differs from absorption and stripping
• the second fluid phase is usually created by thermal means
(vaporization and condensation)
• rather than by the introduction of a second phase that may contain
an additional component or components not present in the feed
mixture
5. BITS Pilani, Pilani Campus
Distillation of a binary mixture
of benzene and toluene
6. BITS Pilani, Pilani Campus
• Feed flow rate, composition, temperature, pressure, and phase
condition
• Desired degree of component separation
• Operating pressure (which must be below the critical pressure of
the mixture)
• Pressure drop, particularly for vacuum operation
• Minimum reflux ratio and actual reflux ratio
• Minimum number of equilibrium stages and actual number of
equilibrium stages (stage efficiency)
• Type of condenser (total, partial, or mixed)
• Degrees of liquid reflux subcooling
• Type of reboiler (partial or total)
Design and Analysis Factors
7. BITS Pilani, Pilani Campus
• Type of trays or packing
• Column height
• Feed-entry stage
• Column diameter
• Column internals, and materials of construction
• Heat lability and chemical reactivity of feed components
Design and Analysis Factors
8. BITS Pilani, Pilani Campus
• Temperature and phase of the feed are determined at
the feed-tray pressure by an adiabatic-flash calculation
across the feed valve
• As the feed vapor fraction increases
• the required reflux ratio (L/D) increases
• but the boilup ratio (V/B) decreases
• The column operating pressure in the reflux drum should
correspond to a distillate temperature
• Some what greater than the supply temperature of the cooling
water to the overhead condenser
Some Initial Considerations
9. BITS Pilani, Pilani Campus
• However, if this pressure approaches the critical
pressure of the more volatile component
• then a lower pressure must be used and a refrigerant is required
as coolant
• If the estimated pressure is less than atmospheric,
• the operating pressure at the top is often set just above
atmospheric to avoid vacuum operation
• unless the temperature at the bottom of the column is limited by
decomposition, polymerization, excessive corrosion, or other
chemical reactions
• In that case, vacuum operation is necessary
Some Initial Considerations
10. BITS Pilani, Pilani Campus
• For given (1) feed, (2) desired degree of separation, and
(3) operating pressure
• A minimum reflux ratio exists
• that corresponds to an infinite number of theoretical stages
• A minimum number of theoretical stages exists
• that corresponds to an infinite reflux ratio
• The design trade-off is between the number of stages and the
reflux ratio
Some Initial Considerations
11. BITS Pilani, Pilani Campus
• Successful applications of distillation methods
• Depends greatly upon an understanding of the equilibria existing
between vapor and liquid phases of the mixture
Vapor-Liquid Equilibrium
Relations
12. BITS Pilani, Pilani Campus
• An ideal law, can be defined for vapor-liquid phases in
equilibrium (only ideal solution e.g. benzene-toluene,
hexane-heptane etc.)
• Composition in liquid:
• Composition in vapor:
Phase Rule and Raoult’s Law
AAA xPp =
BA xx +=1
BA yy +=1
13. BITS Pilani, Pilani Campus
• Boiling-point diagram for system benzene (A)-toluene (B)
at a total pressure of 101.32 kPa.
Constant Pressure Equilibria
Dew point is the temperature at which the
saturated vapour starts to condense.
Bubble-point is the temperature at which
the liquid starts to boil.
The difference between liquid and vapour
compositions is the basis for distillation
operations.
If we start with a cold liquid composition is
xA1 = 0.318 (xB1 = 0.682) and heat the
mixture, it will start to boil at 98ºC.
The first vapor composition in equilibrium
is yA1 = 0.532 (yB1 = 0.468).
Continue boiling, the composition xA will
move to the left since yA is richer in A.
14. BITS Pilani, Pilani Campus
• The boiling point diagram can be calculated from
• (1) the pure vapor-pressure data in the table below and
• (2) the following equations:
Constant Pressure Equilibria
Ppp BA =+
PxPxP ABAA =−+ )1(
P
xP
P
p
y AAA
A ==
16. BITS Pilani, Pilani Campus
• Calculate the vapor and liquid compositions in
equilibrium at 95ºC (368.2K) for benzene-toluene using
the vapor pressure from the table at 101.32 kPa.
• Solution: At 95ºC from Table for benzene, PA = 155.7
kPa and PB = 63.3 kPa. Substituting into Eq.(5) and
solving,
155.7(xA) + 63.3(1-xA) = 101.32 kPa (760 mmHg)
Hence, xA= 0.411 and xB= 1 – xA = 1 - 0.411 = 0.589.
Substituting into eqn.(6),
Constant Pressure Equilibria
PxPxP ABAA =−+ )1(
632.0
32.101
)411.0(7.155
====
P
xP
P
p
y AAA
A
17. BITS Pilani, Pilani Campus
• A common method of plotting the equilibrium data is
• yA is plotted versus xA for the benzene-toluene system
• The 45º line is given to show that yA is richer in component A
than is xA.
Constant Pressure Equilibria
18. BITS Pilani, Pilani Campus
• An azeotrope is a mixture of two or more liquids in such
a ratio that its composition cannot be changed by simple
distillation.
• The maximum temperature Tmax corresponds to a
concentration xAZ and xAZ = yAZ
• The plot of yA versus xA would show the curve crossing the 45o
line at this point
• Acetone-chloroform is an example
• A minimum boiling azeotrope with yAZ = xAZ at Tmin
• Ethanol-water is such a system
Nonideal System
19. BITS Pilani, Pilani Campus
Nonideal System
Maximum-boiling azeotropeMinimum-boiling azeotrope
A mixture whose total pressure is
greater than that computed from
ideality
A mixture whose total pressure is
less than that computed from
ideality
21. BITS Pilani, Pilani Campus
• It is a measure of the differences in volatility between 2
components
• hence their boiling points
• It indicates how easy or difficult a particular separation will be
• Where αAB is the relative volatility of A with respect to B in the
binary system.
• Raoult’s Law:
• when αAB is above 1.0, a separation is possible.
Relative Volatility of Vapor-
Liquid Systems
)1)(1(
/
/
/
AA
AA
BB
AA
AB
xy
xy
xy
xy
−−
==α
AAB
AAB
A
x
x
y
)1(1 −+
=
α
α
P
xP
y AA
A =
B
A
AB
P
P
=α
P
xP
y BB
B =
22. BITS Pilani, Pilani Campus
• A single equilibrium stage is
• the two different phases are brought into intimate contact with
each other
• The mixing time is long enough and the components are
essentially at equilibrium in the two phases after separation
• Total mass balance:
• Component balance:
Single-Stage Equilibrium Contact
for Vapor-LiquidSystem
V1 V2
L0 L1
Where
V1, V2 is a vapor
L0, L1is a liquid
MVLVL =+=+ 1120
AMAAAA MxyVxLyVxL =+=+ 11112200
23. BITS Pilani, Pilani Campus
• Distillation has two main methods in practice:
• Production of vapor by boiling the liquid mixture to be separated
in a single stage and recovering and condensing the vapors
• No liquid is allowed to return to the single-stage still to contact
the rising vapors
• Returning of a portion of the condensate to the still
• The vapors rise through a series of stages or trays, and part of the
condensate flows downward through the series of stages or trays
countercurrently to the vapors (“fractional distillation, distillation with
reflux, or rectification”)
Simple Distillation Methods
24. BITS Pilani, Pilani Campus
• There are 3 important types of distillation that occur in a
single stage or still
• Equilibrium or Flash Distillation
• Simple batch or differential distillation
• Simple steam distillation
Simple Distillation Methods
25. BITS Pilani, Pilani Campus
• Single stage separation technique
• A liquid mixture is pumped through a heater to raise the
temperature and enthalpy of the mixture
• It then flows through a valve and the pressure is reduced,
causing the liquid to partially vaporize
• Once the mixture enters a big enough volume (the “flash drum”),
the liquid and vapor separate
• Because the vapor and liquid are in such close contact up until
the “flash” occurs, the product liquid and vapor phases approach
equilibrium
Equilibrium or Flash
Distillation
26. BITS Pilani, Pilani Campus
• Total mass balance:
• Component balance:
• Material balance for more volatile component :
• Where, f = V/F = molal fraction of the feed that is vaporized and
withdrawn continuously as vapor
• 1-f = one as liquid
heater
SeparatorLVF +=
AAF LxyVFx +=
AAF xfyfx )1( −+=AAF x
F
V
F
F
y
F
V
x )()( −+=
27. BITS Pilani, Pilani Campus
• A mixture of 50% mole normal heptane and 50% normal
octane at 30ºC is continuously flash distilled at 1
standard atmosphere so that 60 mol% of the feed is
vaporized. What will be the composition of the vapor and
liquid products?
Problem
xA 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
yA 0.247 0.453 0.607 0.717 0.796 0.853 0.898 0.935 0.968
Solution: Given: xF = 0.5, f = 0.6; Find: xA, yA
Basis: F = 100 mols
Applying the mass balance yields:
Since
LVF +=
60)100(6.0 === fFV
4060100 =−=−= VFL
28. BITS Pilani, Pilani Campus
Material balance for more volatile component,
Subtituting value of f =0.6 and xF =0.5 we get,
Assuming that xA = 0.5 and solving yA = 0.5.
Next, assuming that xA=0 and solving, yA = 0.83.
(These point are plotted on the graph.)
At the intersection of this line with the equilibrium curve,
yA = 0.58 and xA = 0.39.
AAF xfyfx )1( −+=
AAF x
F
V
F
F
y
F
V
x )()( −+=
AA xy )6.01(6.05.0 −+=
AA xy 4.06.05.0 +=
29. BITS Pilani, Pilani Campus
yA
xA
xF =0.5
yF = 0.5
x=0
y-intercept= 0.834
xA =0.39
yA = 0.58
1st
2nd
3th
30. BITS Pilani, Pilani Campus
Simple Batch or Differential
Distillation
• The pot is filled with liquid
mixture and heated.
• Vapour flows upwards though
the column and condenses at
the top.
• Part of the iquid is returned to
the column as reflux, and the
remainder withdrawn as
distillate.
• Nothing is added or withdrawn
from the still until the run is
completed.
32. BITS Pilani, Pilani Campus
• The total moles of component A left in the still nA will be
nA = xn
• Where,
• n is the moles of liquid left in the still at a given time
• y and x is the vapor and liquid compositions
• If a small amount of liquid dn is vaporized
• the change in the moles of component A is ydn, or dnA.
• Differentiating equation gives
Simple Batch or Differential
Distillation
ydnxdnndx
xdnndxxnddnA
=+
+== )(
xy
dx
n
dn
−
=
33. BITS Pilani, Pilani Campus
• dx/(y-x) can be integrated graphically or numerically
using tabulated equilibrium data or an equilibrium curve
• For ideal mixture:
Simple Batch or Differential
Distillation
∫∫ =
−
=
1
0 0
1
1
0
ln
x
x
n
n
n
n
xy
dx
n
dn
xy
dx
n
dn
−
= Rayleigh equation
B
A
AB
B
A
x
x
y
y
α=
B
B
AB
A
A
B
A
AB
B
A
B
A
n
dn
n
dn
n
n
dn
dn
dndn
dndn
α
α
=
==
AB
A
A
B
B
n
n
n
n
α/1
00
=
B
B
AB
A
A
n
n
n
n
00
lnln α=
Integrating
34. BITS Pilani, Pilani Campus
• A batch of crude pentane contains 15 mole percent n-butane and 85 percent n-
pentane. If a simple batch distillation at atmospheric pressure is used to remove
90 percent of butane, how much pentane will be removed? What will be the
composition of the remaining liquid?
Solution: An average value of 3.5 is used for αAB.
Basis: 1 mol feed
(butane) (pentane)
From equation:
nB = total mole of B left in still, nA = total mole A left in still.
n0B = total initial mole of B in still, n0A = total initial mole A in still.
Problem
15.0=OAn 015.0=An 85.0=OBn
AB
A
A
B
B
n
n
n
n
α/1
00
=
35. BITS Pilani, Pilani Campus
• Total mole of liquid left in still:
• Mole fraction of butane in liquid left:
( ) 518.01.0
85.0
5.3/1
==Bn
440.0)85.0(518.0 ==Bn
moln 455.0015.044.0 =+=
033.0
455.0
015.0
==Ax
36. BITS Pilani, Pilani Campus
• At atmospheric pressure high boiling liquids cannot be
purified by distillation
• Since the components of the liquid may decompose at high
temperature required
Simple Steam Distillation
37. BITS Pilani, Pilani Campus
• Often the high temperature substances are essentially
insoluble in water
• So a separation at lower temperatures can be obtained by
simple steam distillation
• This method is often used to separate a high boiling
component from small amount of nonvolatile impurities
• If the total pressure is fixed
• Since there are two liquid phases, each will exert its own
vapor pressure at the prevailing temperature and cannot
be influenced by the presence of the other
Simple Steam Distillation
38. BITS Pilani, Pilani Campus
• When the sum of the separate vapor pressures equals
the total pressure, the mixture boils and
• Where
• PA is vapor pressure of pure water A
• PB is vapor pressure of pure B
• Then the vapor composition is
• The ratio moles of B distilled to moles of A distilled is
Simple Steam Distillation
PPP BA =+
P
P
y A
A =
P
P
y B
B =
A
B
A
B
P
P
n
n
=
39. BITS Pilani, Pilani Campus
• This method has the disadvantage that
• Large amount of heat must be used to evaporate the water
simultaneously with the high boiling compounds
Simple Steam Distillation
40. BITS Pilani, Pilani Campus
• A mixture contains 100 kg of H2O and 100 kg of ethyaniline (mol wt = 121.1
kg/kg mol), which is immiscible with water. A very slight amount of
nonvolatile impurity is dissolved in the organic. To purify the ethyaniline it is
steam-distilled by bubbling saturated steam into the mixture at a total
pressure of 101.32 kPa (1 atm). Determine the boiling point of the mixture
and the composition of the vapor. The vapor pressure of each of the pure
compounds is as follows (T1):
Problem
Temperature PA(water)
(kPa)
PB(ethylaniline)
(kPa)
K ºC
353.8 80.6 48.5 1.33
369.2 96.0 87.7 2.67
372.3 99.15 98.3 3.04
386.4 113.2 163.3 5.33
41. BITS Pilani, Pilani Campus
Solution
PPP BA =+
Temperature PA
(water)
(kPa)
PB
(ethylaniline)
(kPa)
P=PA+PB
(kPa)
K ºC
353.8 80.6 48.5 1.33 49.83
369.2 96.0 87.7 2.67 90.37
372.3 99.15 98.3 3.04 101.34
386.4 113.2 163.3 5.33 169.23
The boiling temperature = 99.15ºC since total pressure in this temperature is
equal to atmospheric pressure.
The vapor composition are:
97.0
32.101
3.98
===
kPa
kPa
P
P
y A
A
03.0
32.101
04.3
===
P
P
y B
B
42. BITS Pilani, Pilani Campus
• A column containing the equivalent of N theoretical
stages
• a total condenser in which the overhead vapor leaving the top
stage is totally condensed to a bubble point
• liquid distillate and a liquid reflux that is returned to the top stage
• a partial reboiler in which liquid from the bottom stage is partially
vaporized to give a liquid bottoms product
• vapor boilup that is returned to the bottom stage and
• An intermediate feed stage.
Distillation with Reflux and
McCabe- Thiele method
43. BITS Pilani, Pilani Campus
Distillation with Reflux and
McCabe- Thiele method
44. BITS Pilani, Pilani Campus
• For components with close boiling points
• the temperature change over the column is small and relative
volatility is almost constant
Distillation with Reflux and
McCabe- Thiele method
45. BITS Pilani, Pilani Campus
• In 1925, McCabe and Thiele [5] published a graphical
method for combining the equilibrium curve with material
balance operating lines to obtain
• for a binary-feed mixture and selected column pressure
• the number of equilibrium stages and
• reflux required for a desired separation of feed components
Distillation with Reflux and
McCabe- Thiele method
46. BITS Pilani, Pilani Campus
• Typical input specifications and results (outputs) from the
McCabe–Thiele construction for a single-feed, two-
product distillation are
Distillation with Reflux and
McCabe- Thiele method
47. BITS Pilani, Pilani Campus
Distillation with Reflux and
McCabe- Thiele method
48. BITS Pilani, Pilani Campus
• From the specification of xD and xB for the LK, distillate
and bottoms rates, D and B, are fixed by material
balance, since
• But, B = F – D and therefore,
• Besides the equilibrium curve, the McCabe–Thiele
method includes
• A 45o reference line, operating lines for the upper rectifying
section and the lower stripping section of the column, and a fifth
line (the q-line or feed line) for the phase or thermal condition of
the feed.
Distillation with Reflux and
McCabe- Thiele method
50. BITS Pilani, Pilani Campus
• The rectifying section of equilibrium stages extends from
the top stage, 1, to just above the feed stage, f
• Consider a top portion of the rectifying stages, including
the total condenser
Rectifying-Section Operating
Line
51. BITS Pilani, Pilani Campus
• A material balance for the LK over the envelope for the
total condenser and stages 1 to n is as follows:
• Solving for yn+1 gives the equation for the rectifying
section operating line:
• This equation relates LK compositions yn+1 and xn of
passing streams Vn+1 and Ln, respectively
Rectifying-Section Operating
Line
52. BITS Pilani, Pilani Campus
• This straight line equation is the locus of compositions of
all passing streams in the rectifying section
• L and V must not vary from stage to stage in the rectifying
section
• This is the case if:
• The two components have equal and constant molar enthalpies
of vaporization (latent heats)
• Component sensible-enthalpy changes (CPDT) and heat of
mixing are negligible compared to latent heat changes
• The column is insulated, so heat loss is negligible
• Column pressure is uniform (thus, no pressure drop).
Rectifying-Section Operating
Line
53. BITS Pilani, Pilani Campus
• These assumptions leading to the condition of constant
molar overflow in the rectifying section
• Since a total material balance for the rectifying-section
envelope gives Vn+1 = Ln + D
• if L is constant, then V is also constant for a fixed D
• Rewriting equation:
• Thus, the slope of the operating line in the rectifying
section is a constant L/V, with V > L and L/V < 1
Rectifying-Section Operating
Line
55. BITS Pilani, Pilani Campus
• For constant molar overflow in either the rectifying or the
stripping section, only material balances and an
equilibrium curve are required
• Energy balances are needed only to determine
condenser and reboiler duties
• Liquid entering stage 1 at the top is the external reflux
rate, L0, and its ratio to the distillate rate, L0=D, is reflux
ratio R
• Because of constant molar overflow, R = L/D is a
constant in the rectifying section
Rectifying-Section Operating
Line
56. BITS Pilani, Pilani Campus
• Since V = L+ D, the slope of the operating line is readily
related to the reflux ratio:
• Similarly,
• Combining equations produces the most useful form of
the operating line for the rectifying section:
• If R and xD are specified, plots as a straight line
Rectifying-Section Operating
Line
57. BITS Pilani, Pilani Campus
• The stripping section extends from the feed to the
bottom stage
Stripping-Section Operating
Line
Consider a bottom portion of stripping
stages including the partial re-boiler and
extending up from stage N to stage m+1,
below the feed entry
58. BITS Pilani, Pilani Campus
• A material balance for the LK over the envelope results
in
• Solving for ym+1:
• where L and V are total molar flows (which may be different from
L and V in the rectifying section because of feed addition)
• Vapor leaving the partial reboiler is assumed to be in
equilibrium with the liquid bottoms product, B, making
the partial reboiler an equilibrium stage
Stripping-Section Operating
Line
59. BITS Pilani, Pilani Campus
• With the constant-molar overflow assumption, VB =
is constant in the stripping section
• Since
Stripping-Section Operating
Line