Distillation is a method of separating mixtures based on differences in their volatilities through boiling and condensation. Key points:
- It involves heating a mixture to vaporize more volatile components, cooling to condense the vapor into separate products.
- Common uses include separating crude oil, purifying water and air, producing alcoholic beverages.
- Types include simple, fractional, flash, and vacuum distillation. Flash distillation partially vaporizes a liquid through pressure reduction.
- Distillation columns contain internals like trays or packings to facilitate vapor-liquid contact during separation. Fractional distillation uses multiple equilibrium stages for high purity products.
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.
There are three main types of evaporators: natural circulation, forced circulation, and film evaporators. Natural circulation evaporators include evaporating pans, evaporating stills, and short tube evaporators. Forced circulation evaporators use pumps to circulate the liquid through a heated tube bundle. Film evaporators spread the liquid as a thin film over a heated surface, including wiped film, long tube climbing film, and long tube falling film evaporators. Each type has distinct construction features and advantages for different applications in concentrating liquids and removing solvents.
The document discusses different types of distillation processes including simple distillation, fractional distillation, flash distillation, distillation under reduced pressure, and steam distillation. It defines distillation as a method of separation using selective vaporization and condensation. For each process, it covers the principles, equipment setup, working, advantages, disadvantages, and applications. The key principles discussed include Raoult's law, Dalton's law, and how distillation separates mixtures based on differences in boiling points.
The document discusses various evaporation techniques used to concentrate solutions by removing water or other volatile solvents, including horizontal tube evaporators, vertical tube evaporators, climbing film evaporators, falling film evaporators, and forced circulation evaporators. It describes the basic principles, components, working, advantages, and applications of each evaporator type. The key purpose of evaporation is to concentrate aqueous solutions by removing water.
Definition of drying
Importance of drying
Difference between drying and evaporation
Drying is defined as removal of the liquid from a material by application of heat & is accomplished by transfer of a liquid from the surface into an unsaturated vapor phase .
Drying is the final removal of water from material (usually by heat)
Drying is commonly the last stage in a manufacture process
Non-thermal drying
1- As Squeezing wetted sponge
2- Adsorption by desiccant (desiccation)
3- Extraction.
Preservation of drug products
Preparation of bulk drugs
Improved handling
Improved characteristics
Equipments
Drying is necessary in order to avoid deterioration. A few examples are…
--blood products, tissues… undergo microbial growth
--effervescent tablets, synthetic & semi synthetic drugs undergo…. chemical decomposition.
The document describes the plate and frame filter press. It has the following key points:
1. It uses surface filtration where slurry enters the frame under pressure and flows through the filter medium, with filtrate collected on the plates.
2. It is made of plates and frames, usually of aluminum alloy, with studded or grooved plates to support the filter cloth.
3. Multiple plates and frames are arranged in parallel to increase filtration rate, with inlet and outlet channels connecting the plates and frames.
4. It operates in two steps - filtration where cake is formed, and washing using additional wash plates and channels to efficiently wash the entire cake surface.
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.
There are three main types of evaporators: natural circulation, forced circulation, and film evaporators. Natural circulation evaporators include evaporating pans, evaporating stills, and short tube evaporators. Forced circulation evaporators use pumps to circulate the liquid through a heated tube bundle. Film evaporators spread the liquid as a thin film over a heated surface, including wiped film, long tube climbing film, and long tube falling film evaporators. Each type has distinct construction features and advantages for different applications in concentrating liquids and removing solvents.
The document discusses different types of distillation processes including simple distillation, fractional distillation, flash distillation, distillation under reduced pressure, and steam distillation. It defines distillation as a method of separation using selective vaporization and condensation. For each process, it covers the principles, equipment setup, working, advantages, disadvantages, and applications. The key principles discussed include Raoult's law, Dalton's law, and how distillation separates mixtures based on differences in boiling points.
The document discusses various evaporation techniques used to concentrate solutions by removing water or other volatile solvents, including horizontal tube evaporators, vertical tube evaporators, climbing film evaporators, falling film evaporators, and forced circulation evaporators. It describes the basic principles, components, working, advantages, and applications of each evaporator type. The key purpose of evaporation is to concentrate aqueous solutions by removing water.
Definition of drying
Importance of drying
Difference between drying and evaporation
Drying is defined as removal of the liquid from a material by application of heat & is accomplished by transfer of a liquid from the surface into an unsaturated vapor phase .
Drying is the final removal of water from material (usually by heat)
Drying is commonly the last stage in a manufacture process
Non-thermal drying
1- As Squeezing wetted sponge
2- Adsorption by desiccant (desiccation)
3- Extraction.
Preservation of drug products
Preparation of bulk drugs
Improved handling
Improved characteristics
Equipments
Drying is necessary in order to avoid deterioration. A few examples are…
--blood products, tissues… undergo microbial growth
--effervescent tablets, synthetic & semi synthetic drugs undergo…. chemical decomposition.
The document describes the plate and frame filter press. It has the following key points:
1. It uses surface filtration where slurry enters the frame under pressure and flows through the filter medium, with filtrate collected on the plates.
2. It is made of plates and frames, usually of aluminum alloy, with studded or grooved plates to support the filter cloth.
3. Multiple plates and frames are arranged in parallel to increase filtration rate, with inlet and outlet channels connecting the plates and frames.
4. It operates in two steps - filtration where cake is formed, and washing using additional wash plates and channels to efficiently wash the entire cake surface.
The forced circulation evaporator uses a pump to circulate liquid through steam-jacketed tubes at high pressure, preventing boiling. This superheated liquid exits the tubes into a flash chamber where the sudden pressure drop causes flashing to vapor. A deflector separates the vapor from the concentrated liquid, which returns to the pump for further evaporation. Forced circulation provides efficient heat transfer, separation of phases, and suitability for concentrating thermolabile or high viscosity substances, though the equipment has higher costs due to powering the pump.
Drying is defined as the removal of water or other liquids from a material through the application of heat. It involves three steps: heat transfer to the material, mass transfer of moisture to the surface and evaporation, and transfer of vapor away from the material. There are several theories that describe the drying mechanism, including diffusion, capillarity, and pressure gradient theories. The drying rate curve shows an initial adjustment period, constant rate period, falling rate periods, and an equilibrium moisture content where drying stops. Factors like material properties, air conditions, and particle size influence the drying process and rate.
The climbing film evaporator uses long, narrow steam-jacketed tubes to heat and evaporate liquid. As the preheated liquid rises through the tubes, bubbles form and coalesce into larger bubbles that trap liquid and rise as well. This forms a liquid film on the tube walls that rapidly vaporizes. The mixture of vapor and entrained liquid is then separated by an entrainment separator at the top, with vapor exiting and concentrated liquid collected below. Climbing film evaporators are well-suited for heat-sensitive and foaming liquids due to their short contact time and ability to break foam. However, they are also expensive to construct and maintain.
The document discusses various topics related to drying of solids, including the classification of dryers, principles of drying, temperature patterns in dryers, heat transfer during drying, phase equilibria, and the drying curve. It describes different types of dryers such as adiabatic dryers, non-adiabatic dryers, and cross-circulation dryers. It also discusses factors that influence the drying process such as the nature of the solid, methods of contacting the solid and gas, and how drying occurs in three phases - initial, constant rate, and falling rate periods.
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities in heating and cooling processes. It involves selectively boiling the more volatile components by heating the mixture and then condensing the vapor.
There are several types of distillation including simple distillation, fractional distillation, steam distillation and vacuum distillation. Simple distillation is used to separate components with large differences in volatility, while fractional distillation allows separation of mixtures with components of similar volatility by conducting multiple distillation steps. Distillation finds applications in purification of solvents, separation of essential oils, and production of alcoholic beverages and petroleum products among others. Key aspects of distillation systems include the still, condenser and
This document discusses fluidized bed dryers (FBDs) used in pharmaceutical manufacturing. It provides information on:
1) The principle of fluidization where hot air is passed through granules in a container, lifting and suspending them in a "fluidized state" for drying.
2) The construction of FBDs using stainless steel with a detachable bowl, fan, filters and air inlets/outlets.
3) The working where granules are placed in the dryer and hot air flows through them to achieve drying before the air exits.
The document discusses evaporation and different types of evaporators used in evaporation processes. It defines evaporation as the process of removing water or other volatile solvent from an aqueous solution by heating. Various factors that affect evaporation rate are also outlined, such as temperature, vapor pressure, surface area, etc. Different types of evaporators described include open kettle, horizontal tube, vertical tube, falling film, forced circulation, and multiple effect evaporators. Applications of evaporation in industries like pharmaceuticals, food processing, and water treatment are also mentioned.
3. economy of multiple effect evaporatorShital Patil
A multiple-effect evaporator, as defined in chemical engineering, is an equipment for efficiently using the heat from steam to evaporate water.
Steam is mostly used as heating medium in Multiple effect evaporator.
Multiple Effect Evaporation remains one of the popular method for the concentration of aqueous solutions.
This document provides an overview of drying as an important unit operation in the pharmaceutical industry. It discusses the purposes of drying, different periods of drying, and classifications of dryers. It also describes several types of dryers commonly used in the pharmaceutical industry, including tray dryers, rotary dryers, fluidized bed dryers, freeze dryers, and dryers for slurries and suspensions. Special dryers like microwave and radio frequency dryers are also briefly mentioned.
Distillation is a process that separates mixtures into their component parts based on differences in their boiling points. It involves vaporizing a liquid mixture and condensing the vapor to obtain purified fractions. There are several types of distillation processes that can be used for applications like purification of organic solvents, separation of drugs and petroleum products, and recovery of volatile oils and solvents. Some key distillation techniques described in the document include simple distillation, fractional distillation, distillation under reduced pressure, steam distillation, and molecular distillation.
introduction, theory of drying, applications of drying, construction & working about fluidised bed dryer,use of tray dryer,construction about vacuum dryer, construction & working about drum dryer, construction about spray dryer
Evaporation is a separation process where a solvent is vaporized from a solution to concentrate it. There are several types of evaporators used in evaporation, including horizontal tube evaporators, vertical tube evaporators, and climbing film evaporators. Multiple effect evaporators can reuse vapor from one effect in the next to improve heat economy. Evaporation finds applications in industries like sugar production, dairy processing, fertilizer production, and petroleum refining to separate and concentrate components.
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.
Molecular distillation is a distillation process that occurs under high vacuum conditions. This allows molecules to travel through the vapor phase without intermolecular collisions before condensing individually on a nearby surface. There are two main types of molecular stills - falling film stills and centrifugal stills. Falling film stills use a heated surface and wipers to create a thin liquid film for evaporation, while centrifugal stills rotate a bucket at high speeds to create an evaporating liquid film on the inner wall. Both utilize a short path between evaporation and condensation surfaces to minimize molecular collisions in the vapor phase. Molecular distillation is useful for separating compounds with similar boiling points.
Evaporation is the process where a liquid is converted into a gas below the boiling point due to heat. It occurs at the surface of the liquid as mass is transferred from the surface. Several factors affect evaporation such as temperature, vapor pressure, surface area, and time. Common evaporators used are steam jacketed kettles, horizontal tube evaporators, and rising film evaporators. Steam jacketed kettles are simple but less efficient while rising film evaporators provide a large heat transfer area and minimize contact time.
The document discusses multiple effect evaporators, which are used to efficiently concentrate solutions by removing solvent, mainly water, through evaporation. It explains that multiple effect evaporators use heat from steam to evaporate water in multiple stages, making the process more economical than single effect evaporators. Multiple effect evaporators are divided into three categories based on feed direction: forward feed, backward feed, and mixed feed. They have various applications like product concentration, solvent recovery, and crystallization. Key advantages include being an advanced system that is easy to operate and maintain cost effectively.
This document provides an overview of crystallization processes. It discusses how crystals form from solutions or melts via nucleation and growth. Primary and secondary nucleation are described. Mass transfer and population balance theories are used to model crystal growth rates and size distributions. The document outlines how continuous crystallizers like MSMPR systems operate and how residence time affects crystal size distribution. Methods for controlling crystal size like double draw-off, fines removal, and classified product removal are also summarized.
Vacuum distillation allows purification of compounds that cannot be readily distilled under normal atmospheric pressure or that may decompose at high temperatures. It works by reducing pressure above the boiling liquid, lowering the boiling point so compounds evaporate and separate based on differences in their boiling points. Key advantages are faster processing, ability to distill higher boiling point solvents without damage, and improved separation, yield, and purity. It finds applications in separating thermolabile substances and preparing extracts while preserving active constituents.
Distillation is a method to separate mixtures based on differences in volatility. It involves boiling the mixture and condensing the vapor produced. Simple distillation produces an impure distillate while fractional distillation uses a fractionating column for multiple vaporization-condensation cycles, allowing better separation. Vacuum distillation uses reduced pressure for distillation at lower temperatures to prevent degradation. Batch distillation processes mixtures in batches while continuous distillation constantly feeds and removes fractions.
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.
The forced circulation evaporator uses a pump to circulate liquid through steam-jacketed tubes at high pressure, preventing boiling. This superheated liquid exits the tubes into a flash chamber where the sudden pressure drop causes flashing to vapor. A deflector separates the vapor from the concentrated liquid, which returns to the pump for further evaporation. Forced circulation provides efficient heat transfer, separation of phases, and suitability for concentrating thermolabile or high viscosity substances, though the equipment has higher costs due to powering the pump.
Drying is defined as the removal of water or other liquids from a material through the application of heat. It involves three steps: heat transfer to the material, mass transfer of moisture to the surface and evaporation, and transfer of vapor away from the material. There are several theories that describe the drying mechanism, including diffusion, capillarity, and pressure gradient theories. The drying rate curve shows an initial adjustment period, constant rate period, falling rate periods, and an equilibrium moisture content where drying stops. Factors like material properties, air conditions, and particle size influence the drying process and rate.
The climbing film evaporator uses long, narrow steam-jacketed tubes to heat and evaporate liquid. As the preheated liquid rises through the tubes, bubbles form and coalesce into larger bubbles that trap liquid and rise as well. This forms a liquid film on the tube walls that rapidly vaporizes. The mixture of vapor and entrained liquid is then separated by an entrainment separator at the top, with vapor exiting and concentrated liquid collected below. Climbing film evaporators are well-suited for heat-sensitive and foaming liquids due to their short contact time and ability to break foam. However, they are also expensive to construct and maintain.
The document discusses various topics related to drying of solids, including the classification of dryers, principles of drying, temperature patterns in dryers, heat transfer during drying, phase equilibria, and the drying curve. It describes different types of dryers such as adiabatic dryers, non-adiabatic dryers, and cross-circulation dryers. It also discusses factors that influence the drying process such as the nature of the solid, methods of contacting the solid and gas, and how drying occurs in three phases - initial, constant rate, and falling rate periods.
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities in heating and cooling processes. It involves selectively boiling the more volatile components by heating the mixture and then condensing the vapor.
There are several types of distillation including simple distillation, fractional distillation, steam distillation and vacuum distillation. Simple distillation is used to separate components with large differences in volatility, while fractional distillation allows separation of mixtures with components of similar volatility by conducting multiple distillation steps. Distillation finds applications in purification of solvents, separation of essential oils, and production of alcoholic beverages and petroleum products among others. Key aspects of distillation systems include the still, condenser and
This document discusses fluidized bed dryers (FBDs) used in pharmaceutical manufacturing. It provides information on:
1) The principle of fluidization where hot air is passed through granules in a container, lifting and suspending them in a "fluidized state" for drying.
2) The construction of FBDs using stainless steel with a detachable bowl, fan, filters and air inlets/outlets.
3) The working where granules are placed in the dryer and hot air flows through them to achieve drying before the air exits.
The document discusses evaporation and different types of evaporators used in evaporation processes. It defines evaporation as the process of removing water or other volatile solvent from an aqueous solution by heating. Various factors that affect evaporation rate are also outlined, such as temperature, vapor pressure, surface area, etc. Different types of evaporators described include open kettle, horizontal tube, vertical tube, falling film, forced circulation, and multiple effect evaporators. Applications of evaporation in industries like pharmaceuticals, food processing, and water treatment are also mentioned.
3. economy of multiple effect evaporatorShital Patil
A multiple-effect evaporator, as defined in chemical engineering, is an equipment for efficiently using the heat from steam to evaporate water.
Steam is mostly used as heating medium in Multiple effect evaporator.
Multiple Effect Evaporation remains one of the popular method for the concentration of aqueous solutions.
This document provides an overview of drying as an important unit operation in the pharmaceutical industry. It discusses the purposes of drying, different periods of drying, and classifications of dryers. It also describes several types of dryers commonly used in the pharmaceutical industry, including tray dryers, rotary dryers, fluidized bed dryers, freeze dryers, and dryers for slurries and suspensions. Special dryers like microwave and radio frequency dryers are also briefly mentioned.
Distillation is a process that separates mixtures into their component parts based on differences in their boiling points. It involves vaporizing a liquid mixture and condensing the vapor to obtain purified fractions. There are several types of distillation processes that can be used for applications like purification of organic solvents, separation of drugs and petroleum products, and recovery of volatile oils and solvents. Some key distillation techniques described in the document include simple distillation, fractional distillation, distillation under reduced pressure, steam distillation, and molecular distillation.
introduction, theory of drying, applications of drying, construction & working about fluidised bed dryer,use of tray dryer,construction about vacuum dryer, construction & working about drum dryer, construction about spray dryer
Evaporation is a separation process where a solvent is vaporized from a solution to concentrate it. There are several types of evaporators used in evaporation, including horizontal tube evaporators, vertical tube evaporators, and climbing film evaporators. Multiple effect evaporators can reuse vapor from one effect in the next to improve heat economy. Evaporation finds applications in industries like sugar production, dairy processing, fertilizer production, and petroleum refining to separate and concentrate components.
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.
Molecular distillation is a distillation process that occurs under high vacuum conditions. This allows molecules to travel through the vapor phase without intermolecular collisions before condensing individually on a nearby surface. There are two main types of molecular stills - falling film stills and centrifugal stills. Falling film stills use a heated surface and wipers to create a thin liquid film for evaporation, while centrifugal stills rotate a bucket at high speeds to create an evaporating liquid film on the inner wall. Both utilize a short path between evaporation and condensation surfaces to minimize molecular collisions in the vapor phase. Molecular distillation is useful for separating compounds with similar boiling points.
Evaporation is the process where a liquid is converted into a gas below the boiling point due to heat. It occurs at the surface of the liquid as mass is transferred from the surface. Several factors affect evaporation such as temperature, vapor pressure, surface area, and time. Common evaporators used are steam jacketed kettles, horizontal tube evaporators, and rising film evaporators. Steam jacketed kettles are simple but less efficient while rising film evaporators provide a large heat transfer area and minimize contact time.
The document discusses multiple effect evaporators, which are used to efficiently concentrate solutions by removing solvent, mainly water, through evaporation. It explains that multiple effect evaporators use heat from steam to evaporate water in multiple stages, making the process more economical than single effect evaporators. Multiple effect evaporators are divided into three categories based on feed direction: forward feed, backward feed, and mixed feed. They have various applications like product concentration, solvent recovery, and crystallization. Key advantages include being an advanced system that is easy to operate and maintain cost effectively.
This document provides an overview of crystallization processes. It discusses how crystals form from solutions or melts via nucleation and growth. Primary and secondary nucleation are described. Mass transfer and population balance theories are used to model crystal growth rates and size distributions. The document outlines how continuous crystallizers like MSMPR systems operate and how residence time affects crystal size distribution. Methods for controlling crystal size like double draw-off, fines removal, and classified product removal are also summarized.
Vacuum distillation allows purification of compounds that cannot be readily distilled under normal atmospheric pressure or that may decompose at high temperatures. It works by reducing pressure above the boiling liquid, lowering the boiling point so compounds evaporate and separate based on differences in their boiling points. Key advantages are faster processing, ability to distill higher boiling point solvents without damage, and improved separation, yield, and purity. It finds applications in separating thermolabile substances and preparing extracts while preserving active constituents.
Distillation is a method to separate mixtures based on differences in volatility. It involves boiling the mixture and condensing the vapor produced. Simple distillation produces an impure distillate while fractional distillation uses a fractionating column for multiple vaporization-condensation cycles, allowing better separation. Vacuum distillation uses reduced pressure for distillation at lower temperatures to prevent degradation. Batch distillation processes mixtures in batches while continuous distillation constantly feeds and removes fractions.
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.
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.
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.
Distillation is a process that separates mixtures into individual components based on differences in their boiling points. It works by heating the mixture to vaporize components with lower boiling points, which are then cooled and condensed.
The key principles are that vapor pressure increases with temperature, allowing the lower boiling components to vaporize first. According to Raoult's law, the vapor produced will be enriched in the more volatile components compared to the liquid mixture.
There are several types of distillation including simple, fractional, vacuum, and azeotropic distillation. Simple distillation is used when components have very different boiling points while fractional distillation with multiple stages is needed for similar boiling points. Vacuum distillation lowers the
This document discusses different types of azeotropes:
- An azeotrope is a mixture of liquids that cannot be separated by simple distillation as the vapor has the same composition as the liquid.
- A minimum boiling azeotrope has a boiling point lower than its constituent liquids. Repeated distillation of such a mixture cannot produce a distillate richer in one component than the azeotrope composition.
- A maximum boiling azeotrope has a boiling point higher than its constituent liquids. Repeated distillation of such a mixture results in distillates moving away from the azeotrope composition and residues moving towards it.
This document provides information about azeotropic distillation prepared by Claire E. Canoy for their 2nd year Chemical Engineering Technology course. It defines azeotropic distillation as adding an entrainer component to a feed mixture to form a new azeotrope that can be separated into its components by distillation. The entrainer allows either the separation of a closely boiling pair or the separation of an azeotrope into its components. A diagram shows the process of mixing the feed and entrainer before distillation in two columns to separately remove the key components and recycle the entrainer.
This document provides an introduction to distillation, including:
1) Defining distillation and describing how it separates mixtures based on differences in boiling points.
2) Outlining the main components of distillation columns, including trays/plates, reboilers, condensers, and reflux drums.
3) Explaining the basic operation of distillation columns, including how vapors and liquids flow internally and how feeds, products, and reflux streams flow externally.
4) Describing common types of trays/plates used in distillation columns, including bubble cap, valve, and sieve trays, and how they enhance vapor-liquid contacting.
The document discusses evaporation as a unit operation used to concentrate solutions by removing water or other volatile solvent. It describes different types of evaporators used for this purpose, including batch pans, rising film evaporators, falling film evaporators, and multiple effect evaporators. The key components and working principles of evaporators are explained. Specific examples of evaporation applications are also provided.
An overview of distillation column design concepts and major design considerations. Explains distillation column design concepts, what you would provide to a professional distillation column designer, and what you can expect back from a distillation system design firm. To speak with an engineer about your distillation column project, call EPIC at 314-207-4250.
This presentation details out all the process in an Oil Refinery. If you are looking to have a hawk eye view of all the oil refinery process, this presentation will set you on.
Simple explained.
After crude oil is desalted and dehydrated, it is separated into fractions through distillation. However, the distilled fractions cannot be used directly and require further processing due to differences between crude oil properties and market needs. The complexity of refining processes is also due to environmental regulations that require cleaner products. Distillation involves heating crude oil to separate it based on boiling points, but the distilled fractions need additional conversion processes before they can be used or sold.
Rufoz Hitek is an engineering company that specializes in designing and manufacturing distillation, extraction, and absorption systems. They also offer turnkey projects. The company has over 30 years of experience and is ISO 9001 certified. Their goal is to partner with customers to design customized, efficient, and reliable production solutions that meet all requirements.
"Mixing Innovation in Food Industry".
Seminar on Regional Innovation System and Food.
Derio, 1st April 2011.
Xabier de la Maza
Jon Ander Egaña
Mari Jose Aranguren
Edurne Magro
Distillation Blending and Cutpoint Temperature Optimization (DBCTO) in Schedu...Brenno Menezes
To improve efficiency, effectiveness and economy of mixing/blending, reacting/converting and separating/fractionating inside the oil-refinery.
To integrate blending of several streams’ distillation curves with also shifting or adjusting cutpoints of distilled streams (i.e., initial and/or final boiling-points, IBP and FBP) in order to manipulate their TBP curves in an either off- or on-line environment (Kelly et al, 2014).
This document discusses liquid-liquid extraction (LLE) models, applications, equilibrium relationships, and equipment. Key points include: LLE can be modeled using phase rules and mass balances accounting for temperature, pressure, and compositions of both phases; equilibrium data is needed to calculate stage-by-stage extraction; common equipment includes mixer-settlers, spray columns, and sieve tray towers; and processes that utilize LLE include separation of aromatics and biopharmaceutical production.
The document discusses the benefits of exercise for mental health. It states that regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help alleviate symptoms of mental illness.
This document is an introduction to a workbook called "What Do You Want To Do With Your Life?" by Hans Glint. It aims to help readers develop a life plan by answering the question "What do I want to do with my life?" rather than "What should I do with my life?". The introduction discusses how children are often asked what they want to be when they grow up, but are conditioned to think about their future in terms of what others expect rather than their own desires. It argues the importance of focusing on one's own happiness and changing the question to a empowering form focused on personal wants rather than obligations. The workbook will guide readers through exercises to explore their past, present, and future to develop a
Distillation is a process that separates mixtures into individual components based on differences in their boiling points. It works by heating the mixture to vaporize components with lower boiling points. When the vapor cools, the condensate contains more of the volatile components. Distillation columns contain trays or packings to facilitate contact between the vapor and liquid phases, allowing for efficient separation. Column design is based on vapor-liquid equilibrium data for the specific mixture and aims to achieve the desired separation with minimum energy usage and costs.
The document discusses crude oil refining processes. It begins by explaining that crude oil is initially separated into fractions through distillation, but the distilled fractions require further processing to meet market needs. Additional complexity arises from environmental regulations requiring cleaner products. The document then provides details on various refining processes like distillation, solvent extraction, and cracking used to convert crude oil fractions into useful products like gasoline and diesel.
Distillation is a process that separates liquid mixtures into individual fractions based on differences in boiling points. It works by heating the mixture to vaporize components with lower boiling points, which are separated from higher-boiling components as vapors rise and condense. Distillation columns continuously process feed streams and are the most common type, while batch columns introduce feed in discrete batches. Distillation units have components like trays or packings for enhanced separation, a reboiler for vaporization, a condenser to condense vapors, and a reflux drum to collect condensed liquids and return some to the column. Separation depends on differences in vapor pressure and relative volatility between mixture components.
Distillation is a process that separates liquid mixtures into individual fractions based on differences in boiling points. It works by heating the mixture to vaporize components with lower boiling points. There are two main types of distillation columns - batch columns which process feed intermittently, and continuous columns which process a steady stream of feed. Distillation columns contain internals like trays or packings to enhance separation, a reboiler for vaporization, a condenser to cool vapors, and a reflux drum to collect condensed liquids and provide reflux. Separation occurs due to differences in vapor pressure and relative volatility between components in the mixture.
This document discusses different types of distillation processes used to separate liquid mixtures based on volatility. It focuses on the design and components of distillation columns. Distillation processes separate mixtures through evaporation and condensation, and include simple, fractional, vacuum, and steam distillation. A distillation column consists of a vertical shell containing internal trays or packings to facilitate separation, and components like a condenser, reboiler, and reflux drum. The condenser converts vapors into liquid, the reboiler generates vapors from the column bottom, and the reflux drum holds condensed vapors to recirculate liquid back up the column.
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.
Slides for the eLearning course Separation and purification processes in biorefineries (https://open-learn.xamk.fi) in IMPRESS project.
Subject: Distillation
Subject: 0.2 Introduction to distillation.
The document discusses different types of liquid-liquid extraction columns. It describes rotating disc columns, which use countercurrent flow and a rotating disc to agitate the two phases and facilitate mass transfer. Agitated columns are also discussed, using mechanical devices like impellers to create dispersion throughout the column. Various agitated column designs are explored, including baffled columns with mixing and settling zones. Pulse columns are also mentioned as a type of agitated column without internal mechanical parts.
Distillation is a process used to separate mixtures based on differences in their boiling points. It involves heating the mixture until it vaporizes, then cooling the vapors until they condense. There are several types of distillation processes. Simple distillation is used to purify liquids. Fractional distillation separates mixtures with components of different boiling points. Steam distillation is used for mixtures containing water. Vacuum distillation allows distillation of substances that decompose at their normal boiling points. Destructive distillation involves decomposition during heating.
Distillation is one of unit operation which is uses for separation of two or more liquids which have difference in boiling points. Basic theory and calculation of Distillation which will help to understand Distillation and stage calculation. it will be helpful for students who are studying chemical engineering and fresh engineers in chemical process industries.
Distillation is a widely used separation process that separates liquid mixtures into products with different compositions based on volatility. It works by contacting vapor and liquid phases in equilibrium stages, where the more volatile components concentrate in the vapor phase and the less volatile components concentrate in the liquid phase. A distillation column contains multiple equilibrium stages to facilitate separation through a cascade of vapor and liquid flows contacting across the stages from bottom to top. Distillation columns produce an overhead distillate product from the top and a bottoms product from the bottom with different compositions based on volatility.
Distillation is a process of separating mixtures by boiling and condensing their components with differing volatilities. It works by heating a liquid mixture to its boiling point, vaporizing components, and then condensing the vapor to liquid, allowing different components to separate. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and vacuum distillation. Distillation is used in pharmacy to purify water and organic solvents, and prepare volatile oils, aromatic waters, and other official compounds.
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: 0.2 Introduction to distillation.
continuous distillation with rectification process and its working principal with diagram and also its use in industrial applications.
design and operations explained.
Types of Distillation & column internalsBharat Kumar
More:- https://chemicalengineeringworld.com
Distillation is a method of separating the components of a solution which depends upon distribution of the substances between a gas and liquid phase, applied to cases where all components are present in both phases.
* What is distillation ?
* Types of Distillation
* Batch Distillation
* Azeotropic Distillation
* Flooding
* Priming
* Coning
* Weeping
* Dumping
* Packed Column
* Tray column
* Reflux Ratio
* Relative volatility
* Distillation column
Distillation is a method of separating mixtures based on differences in volatility (volatility is the tendency of a substance to vaporize. Volatility is directly related to a substance's vapor pressure.) of components in a boiling liquid mixture. Distillation is a unit operation, or a physical separation process, and not a chemical reaction
Nrl final report BY Muhammad Fahad Ansari 12IEEM14fahadansari131
The document is an internship report submitted by a group of students from various universities in Pakistan who completed internships at National Refinery Limited in Karachi in 2010. It includes an introduction to National Refinery Limited and lists its major products. It also provides descriptions of some of the key equipment used at oil refineries, including distillation columns, reboilers, condensers, and different types of trays used in distillation columns.
The document discusses various topics related to continuous distillation processes including:
1) Material balance diagrams for continuous distillation columns and individual plates within the column. Different sections of the column like the rectifying and stripping sections are identified.
2) Common tray designs for distillation columns including bubble cap trays and sieve trays. Operation of these trays and factors influencing liquid-vapor contact are explained.
3) Operating parameters that can impact column performance are reviewed such as feed conditions, pressure drop across the column, flooding, weeping, entrainment, reboiler temperature control and vacuum maintenance. Column diameter is also noted as an important design factor.
Distillation, distillation process for pharma students, simple distillation, ...RajkumarKumawat11
Distillation, distillation process for pharma students, simple distillation, fractional distillation, distillation under reduced pressure, steam distillation, destructive distillation, water for injection and sterile water
Wauquier, j. p._-_petroleum_refining_i_crude_oil_-_petroleum_products_-_proce...Khalid Nawaz
This document provides an overview of topics related to petroleum refining, including: the composition of crude oil and petroleum products; fractionation and analysis of crude oils; characterization of crude oils and fractions; methods for calculating hydrocarbon properties; characteristics of petroleum products for energy and non-energy uses; standards and specifications for products; evaluation of crude oils; refining activities for motor fuels and lubricants; and an introduction to refining processes. It includes appendices on pure component characteristics and standard test methods.
NPSH (Net Positive Suction Head) refers to the amount of pressure available to prevent cavitation in a pump. It is calculated as the suction pressure plus velocity head minus vapor pressure. The available NPSH (NPSHa) in a system must exceed the required NPSH (NPSHr) specified by the pump manufacturer to avoid cavitation. As a pump's elevation above an open tank increases, the NPSHa decreases and vaporization may occur, limiting the maximum elevation. The maximum elevation depends on atmospheric pressure and fluid vapor pressure, which increases with temperature.
Dynamic pressure represents a fluid's kinetic energy and is defined as one-half the fluid's density multiplied by the square of its velocity. It can be calculated using the formula pd = 1/2 ρ v^2, where pd is the dynamic pressure, ρ is the fluid's density, and v is its velocity. For example, the dynamic pressure of water flowing at 20°C with a density of 1000 kg/m^3 and a velocity of 5 m/s is calculated to be 12.5 kPa.
The Bernoulli equation is a statement of the conservation of energy in fluids. It states that for steady, incompressible flow, the sum of pressure, potential and kinetic energies per unit volume is constant at any point along a streamline. The Bernoulli equation can be used to calculate things like the velocity of fluid flowing out of a tank through an orifice, where increasing velocity decreases pressure and vice versa. It is commonly applied to situations like venturi meters and pitot tubes.
This document discusses different types of pressure sensors. It begins by explaining how pressure is commonly measured in absolute or gauge terms. It then describes various mechanical and electrical methods for pressure measurement, including elastic pressure transducers like Bourdon tubes, diaphragms, and bellows, as well as electric methods using strain gauges, capacitance, piezoelectricity, and resonant wires. Specific types of sensors are then explained in more detail, such as how strain gauges and capacitive sensors detect pressure changes. The document concludes by noting factors like process conditions, pressure range, and required sensitivity that influence the selection of an appropriate pressure sensor.
Test your knowedge in chemical engineering by khalid nawazKhalid Nawaz
This document contains 10 multiple choice questions testing knowledge of chemical engineering concepts. The questions cover topics like chemical dehumidification processes, triangular notch discharge angles, the effect of temperature on water surface tension, the key element that controls steel properties, minimum emissivity surfaces, desalination, cavitation, heat storage capacities, definitions of dry bulb temperature and dew point, and factors that liquid pressure depends on.
Boilers are closed vessels made of steel that transfer heat from fuel combustion to water to generate steam. They come in two main types: fire tube boilers where hot gases pass through tubes surrounded by water, and water tube boilers where water passes through tubes surrounded by hot gases. Boilers must generate maximum steam, be lightweight, safe, affordable, and easy to access for maintenance. Steam is used for power generation, heating, and in chemical processes. Boiler efficiency is important and various accessories like economizers and superheaters are used to improve it. Understanding boilers is essential for the chemical industry as most used are high efficiency, safe water tube designs.
The document compares different flow measuring devices, including orifice meters, Venturi meters, rotameters, and Pitot tubes. It discusses how each device works, including that orifice meters use a drilled plate to measure pressure changes, Venturi meters use converging pipes to increase velocity and measure pressure differences, rotameters measure the position of a float inside a tapered tube, and Pitot tubes measure velocity by comparing static and impact pressures. The document concludes by comparing the devices based on their suitability for different fluid types, pressure losses, accuracy, and most common use in chemical industries.
This document discusses prilling and granulation processes. Prilling involves spraying molten material into a prilling tower where it solidifies into spherical prills due to contact with upward air flow. Granulation converts fine particles into stronger, larger agglomerates using compression or a binding agent. The key difference is that prilling does not use a binder, produces hollow prills of varying sizes with more breakage, while granulation uses a binder to form solid, uniform size particles with less breakage and longer storage life. Granulation is commonly used in pharmaceuticals while prilling is used in fertilizer and explosive manufacturing.
This document provides information on various drying methods and concepts related to drying pharmaceutical materials. It discusses convective drying methods like tray drying and fluidized bed drying. It also covers drum drying, spray drying, vacuum drying, and microwave drying. Key points covered include heat and mass transfer principles in drying, factors that influence drying rate, types of moisture in materials, and terminology used in drying like equilibrium moisture content. Advantages and disadvantages of different drying methods are also summarized.
The document discusses cooling towers, which are used to transfer heat from cooling water to the atmosphere. There are two main types - natural draft towers which use convection to circulate air, and mechanical draft towers which use fans. Mechanical draft towers can be either counter-flow or cross-flow design. The cooling tower cools water by contacting it with air, allowing evaporation which removes heat from the water so it can be recirculated for cooling processes.
Software Engineering and Project Management - Introduction, Modeling Concepts...Prakhyath Rai
Introduction, Modeling Concepts and Class Modeling: What is Object orientation? What is OO development? OO Themes; Evidence for usefulness of OO development; OO modeling history. Modeling
as Design technique: Modeling, abstraction, The Three models. Class Modeling: Object and Class Concept, Link and associations concepts, Generalization and Inheritance, A sample class model, Navigation of class models, and UML diagrams
Building the Analysis Models: Requirement Analysis, Analysis Model Approaches, Data modeling Concepts, Object Oriented Analysis, Scenario-Based Modeling, Flow-Oriented Modeling, class Based Modeling, Creating a Behavioral Model.
artificial intelligence and data science contents.pptxGauravCar
What is artificial intelligence? Artificial intelligence is the ability of a computer or computer-controlled robot to perform tasks that are commonly associated with the intellectual processes characteristic of humans, such as the ability to reason.
› ...
Artificial intelligence (AI) | Definitio
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
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
2. Distillation
• Distillation is a method of separating mixtures based on differences in
their volatilities in a boiling liquid mixture. Distillation is a physical
separation process, and not a chemical reaction.
• Uses:-
1. Crude oil
2. Water is distilled to remove impurities
3. Air is distilled to separate its components
4. Distillation of fermented solutions to produce distilled beverages
with a higher alcohol content.
The premises where distillation is carried out, especially distillation of
alcohol, are known as a distillery.
4. Flash Distillation
⑴ The flash distillation process
consists of three parts.
a. Vaporizing a definite fraction
of the liquid ;
b. Separating the vapor from the
liquid;
c. Condensing the vapor.
Heater
Separator
Condenser
Overhead
Product
Bottom
Product
Throttle
5. Features
a. Continuous steady state
Operating conditions (T & P)
are constant.
b. Compositions & flow rates of
feed , products of overhead
and bottom are constant。
c. There is equilibrium always
between phases of vapor and liquid .
7. Flash Distillation
Flash evaporation is the partial vaporization that occurs when a
saturated liquid stream undergoes a reduction in pressure by passing
through a valve or other device. If the valve or device is located at the
entry into a pressure vessel so that the flash evaporation occurs within
the vessel, then the vessel is often referred to as a flash drum.
If the saturated liquid is a single-component liquid (for example, liquid
propane or liquid ammonia), a part of the liquid immediately "flashes"
into vapor. Both the vapor and the residual liquid are cooled to the
saturation temperature of the liquid at the reduced pressure. This is often
referred to as "auto-refrigeration" and is the basis of most conventional
vapor compression refrigeration systems.
If the saturated liquid is a multi-component liquid (for example, a
mixture of propane, isobutane and normal butane), the flashed vapor is
richer in the more volatile components than is the remaining liquid.
8. Flash Distillation:
Flash distillation (sometimes called "equilibrium distillation") is a single
stage separation technique. A liquid mixture feed 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.
Simple flash separations are very common in industry, particularly
petroleum refining. Even when some other method of separation is to be
used, it is not uncommon to use a "pre-flash" to reduce the load on the
separation itself.
9. When is flash distillation used?
flash distillation = a single equilibrium stage
1. when very crude separation is needed
e.g., oil/water separation in crude oil refining
2. when volatilities of components in the mixture
are very different
e.g., water desalination (4000 plants worldwide, producing 3.4
billion gallons potable H2O daily)
10. Batch Distillation
Production of vapor by boiling the
liquid mixture to be separated and
condensing the vapors without
allowing any liquid to return to the
still.
11. Continuous Distillation
Based on the return of part of the
condensate to the still under such
conditions that this returning liquid
is brought into intimate contact
with the vapors on their way to the
condenser.
12. PLATE CONTACTORS:
Cross flow plate are the most commonly used plate
contactor in distillation. In which liquid flows
downward and vapours flow upward. The liquid move
from plate to plate via down comer. A certain level of
liquid is maintained on the plates by weir.
13. I prefer Sieve Plate because:
• Pressure drop is low as compared to bubble cap trays
• Their fundamentals are well established, entailing low risk.
• The trays are low in cost relative to many other types of
trays.
• They can easily handle wide variations in flow rates.
• They are lighter in weight. It is easier and cheaper to install.
• Maintenance cost is reduced due to the ease of cleaning.
15. BASIC DISTILLATION EQUIPMENT
AND OPERATION
Main Components of Distillation Columns
Distillation columns are made up of several components, each of
which is used either to tranfer heat energy or enhance materail
transfer. A typical distillation contains several major components:
• a vertical shell where the separation of liquid components is carried
out
• column internals such as trays/plates and/or packings which are used
to enhance component separations
• a reboiler to provide the necessary vaporisation for the distillation
process
• a condenser to cool and condense the vapour leaving the top of the
column
• a reflux drum to hold the condensed vapour from the top of the
column so that liquid (reflux) can be recycled back to the column
16. BASIC DISTILLATION EQUIPMENT
AND OPERATION
The vertical shell
houses the column
internals and together
with the condenser
and reboiler,
constitute a
distillation column. A
schematic of a typical
distillation unit with a
single feed and two
product streams is
shown below:
17. BASIC DISTILLATION EQUIPMENT
AND OPERATION
Basic Operation and Terminology
The liquid mixture that is to be processed is
known as the feed and this is introduced usually
somewhere near the middle of the column to a
tray known as the feed tray. The feed tray
divides the column into a top (enriching or
rectification) section and a bottom (stripping)
section. The feed flows down the column where
it is collected at the bottom in the reboiler.
18. BASIC DISTILLATION
EQUIPMENT AND OPERATION
Basic Operation and Terminology
Heat is supplied to the reboiler to
generate vapour. The source of
heat input can be any suitable fluid,
although in most chemical plants
this is normally steam. In refineries,
the heating source may be the
output streams of other
columns. The vapour raised in the
reboiler is re-introduced into the
unit at the bottom of the column.
The liquid removed from the
reboiler is known as the bottoms
product or simply, bottoms.
19. BASIC DISTILLATION EQUIPMENT
AND OPERATION
Basic Operation and Terminology
The vapour moves up the column,
and as it exits the top of the unit,
it is cooled by a condenser. The
condensed liquid is stored in a
holding vessel known as the reflux
drum. Some of this liquid is
recycled back to the top of the
column and this is called the
reflux. The condensed liquid that
is removed from the system is
known as the distillate or top
product.
Thus, there are internal flows of
vapour and liquid within the column
as well as external flows of feeds
and product streams, into and out
of the column.
20. COLUMN INTERNALS
Trays and Plates
The terms "trays" and "plates" are used interchangeably.
There are many types of tray designs, but the most
common ones are :
Bubble cap trays
A bubble cap tray has riser or
chimney fitted over each hole, and
a cap that covers the riser. The
cap is mounted so that there is a
space between riser and cap to
allow the passage of vapour.
Vapour rises through the chimney
and is directed downward by the
cap, finally discharging through
slots in the cap, and finally
bubbling through the liquid on the
tray.
21. • Because of its high cost and complexity, most
modern column designs favour the use of sieve or
valve trays over bubble-cap trays. Bubble-caps
should only be used where very low vapour rates
have to be handled, or adequate residence time is
necessary for separation and/or chemical reaction,
or in applications where a positive liquid seal is
essential at all flow rates.
22. COLUMN INTERNALS
Sieve trays
Sieve trays are simply metal
plates with holes in them.
Vapour passes straight
upward through the liquid on
the plate. The arrangement,
number and size of the holes
are design parameters.
Because of their efficiency, wide
operating range, ease of
maintenance and cost factors,
sieve and valve trays have
replaced the once highly thought
of bubble cap trays in many
applications.
23. • he sieve tray was developed. Sieve tray has almost
the opposite characteristics of the bubble-cap tray.
It is inexpensive to male. With proper design, it has
low pressure drop, fairly good capacity and
efficiency. However, its turn down ratio often does
not meet flexibility demanded by the operating
facility.
24. COLUMN INTERNALS
Liquid and Vapour Flows in a Tray Column
The next few figures show the direction of vapour and
liquid flow across a tray, and across a column.
25. COLUMN INTERNALS
Each tray has 2 conduits, one on each side, called
‘downcomers’. Liquid falls through the downcomers by gravity
from one tray to the one below it. The flow across each plate
is shown in the above diagram on the right.
A weir on the tray ensures that
there is always some liquid
(holdup) on the tray and is
designed such that the the holdup
is at a suitable height, e.g. such
that the bubble caps are covered
by liquid.
Being lighter, vapour flows up the
column and is forced to pass
through the liquid, via the
openings on each tray. The area
allowed for the passage of vapour
on each tray is called the active
tray area.
26. COLUMN INTERNALS
As the hotter vapour passes through the liquid on the tray
above, it transfers heat to the liquid. In doing so, some of
the vapour condenses adding to the liquid on the tray.
The condensate, however, is richer in the less volatile
components than is in the vapour. Additionally, because of
the heat input from the vapour, the liquid on the tray boils,
generating more vapour. This vapour, which moves up to
the next tray in the column, is richer in the more volatile
components. This continuous contacting between vapour
and liquid occurs on each tray in the column and brings
about the separation between low boiling point
components and those with higher boiling
27. COLUMN INTERNALS
Tray Designs
A tray essentially acts as a mini-column, each accomplishing a
fraction of the separation task. From this we can deduce that
the more trays there are, the better the degree of separation
and that overall separation efficiency will depend significantly on
the design of the tray. Trays are designed to maximise vapour-
liquid contact by considering
• the liquid distribution and
• vapour distribution
on the tray. This is because better vapour-liquid contact means
better separation at each tray, translating to better column
performance. Less trays will be required to achieve the same
degree of separation. Attendant benefits include less energy
usage and lower construction costs.
There is a clear trend to improve separations by supplementing
the use of trays by additions of packings.
28. COLUMN INTERNALS
Packings
Packings are passive devices that are designed to
increase the interfacial area for vapour-liquid contact.
The following pictures show 3 different types of packings.
These strangely shaped pieces are supposed to impart good
vapour-liquid contact when a particular type is placed together
in numbers, without causing excessive pressure-drop across a
packed section. This is important because a high pressure drop
would mean that more energy is required to drive the vapour up
the distillation column.
29. COLUMN INTERNALS
Packings versus Trays
A tray column that is facing throughput problems may be
de-bottlenecked by replacing a section of trays with
packings. This is because:
• packings provide extra inter-facial area for liquid-vapour
contact
• efficiency of separation is increased for the same column
height
• packed columns are shorter than trayed columns
Packed columns are called continuous-contact columns
while trayed columns are called staged-contact columns
because of the manner in which vapour and liquid are
contacted.
30. COLUMN REBOILERS
There are a number of designs of reboilers. It is beyond the scope
of this set of introductory notes to delve into their design principles.
However, they can be regarded as heat-exchangers that are
required to transfer enough energy to bring the liquid at the bottom
of the column to boiling boint. The following are examples of typical
reboiler types.
31. DISTILLATION PRINCIPLES
Separation of components from a liquid mixture via
distillation depends on the differences in boiling points of
the individual components. Also, depending on the
concentrations of the components present, the liquid
mixture will have different boiling point characteristics.
Therefore, distillation processes depends on the vapour
pressure characteristics of liquid mixtures.
32. DISTILLATION PRINCIPLES
Vapour Pressure and Boiling
The vapour pressure of a liquid at a particular temperature is the
equilibrium pressure exerted by molecules leaving and entering the
liquid surface. Here are some important points regarding vapour
pressure:
• energy input raises vapour pressure
• vapour pressure is related to boiling
• a liquid is said to ‘boil’ when its vapour pressure equals the
surrounding pressure
• the ease with which a liquid boils depends on its volatility
• liquids with high vapour pressures (volatile liquids) will boil at
lower temperatures
• the vapour pressure and hence the boiling point of a liquid mixture
depends on the relative amounts of the components in the mixture
• distillation occurs because of the differences in the volatility of the
components in the liquid mixture