This document provides an overview of different types of bioreactors and mixing within them. It discusses continuous stirred tank reactors (CSTR), bubble column reactors, airlift reactors, packed bed reactors, and trickle bed reactors. For each type of bioreactor, it describes the basic design and operation and highlights factors that influence mixing, such as mechanical agitation, rising gas bubbles, liquid circulation patterns, and concurrent liquid and gas flow through a fixed catalyst bed.
Bioprocess development and technology-Introduction,History of bioprocess,Milestones of Bioprocess development,Bioprocess development,Impact on Biotechnology
this presentation is all about how the parameters are that are controlled in a bioreactor. it is one of the important chapter in bio process engineering.
Bioprocess development and technology-Introduction,History of bioprocess,Milestones of Bioprocess development,Bioprocess development,Impact on Biotechnology
this presentation is all about how the parameters are that are controlled in a bioreactor. it is one of the important chapter in bio process engineering.
This presentation gives all the required information about pack bed bioreactor, including, advantages, disadvantages, applications and even how to overcome the disadvantages. Packed bed bioreactor is the major type of bioreactor used in waste water treatment as it involves the usage of catalyst. There are different types of packed bed bioreactors and they are used according to the desired product. There is picture representation and also tabular form of differentiation.
I have also mentioned the references at the end.
A bioreactor is an installation for the production of microorganisms outside their natural but inside an artificial environment. The prefix “photo” particularly describes the bio-reactor's property to cultivate phototrophic microorganisms, or organisms which grow on by utilizing light energy.
These organisms use the process of photosynthesis to build their own biomass from light and carbon dioxide. Members of this group are Plants, Mosses, Microalgae, Cyanobacteria and Purple Bacteria.
Photobioreactor or PBR, is the controlled supply of specific environmental conditions for respective species.
Photobioreactor allows much higher growth rates and purity levels than anywhere in natural or habitats similar to nature.
The function of the bioreactor is to provide a suitable environment in
which an organism can efficiently produce a target product—the target product might be.
Cell biomass
Metabolite
Bioconversion Product
The performance of any bioreactor depends on the following key factors:
Agitation rate
Oxygen transfer
pH
Temperature
There is no universal bioreactor.
The general requirements of the bioreactor are as follows:
The design and construction of bioreactors must keep sterility from the start point to end of the process.
Optimal mixing with low, uniform shear.
Adequate mass transfer, oxygen.
Clearly defined flow conditions.
Feeding substrate with prevention of under or overdosing.
Suspension of solids.
Gentle heat transfer.
Compliance with design requirements such as: ability to be sterilized; simple construction; simple measuring, control, regulating techniques; scale-up; flexibility; long term stability; compatibility with up- downstream processes; antifoaming measures.
A fluidized bed reactor (FBR) is a type of reactor device that can be used to carry out a variety of multiphase chemical reactions.
In this type of reactor, a fluid (gas or liquid) is passed through a solid granular material (usually a catalyst possibly shaped as tiny spheres) at high enough velocities to suspend the solid and cause it to behave as though it were a fluid.
This process, known as fluidization, imparts many important advantages to the FBR.
As a result, the fluidized bed reactor is now used in many industrial applications
Batch and Continuous Sterilization of Media in Fermentation Industry Dr. Pavan Kundur
Continuous sterilization is the rapid transfer of heat to medium through steam condensate without the use of a heat exchanger. ... This is more efficient than batch sterilization because instead of expending energy to heat, hold, and cool the entire system, small portions of the inlet streams are heated at a time.
The heart of the fermentation or bioprocess technology is the Fermentor or Bioreactor. A bioreactor is basically a device in which the organisms are cultivated to form the desired products. it is a containment system designed to give right environment for optimal growth and metabolic activity of the organism.
A fermentor usually refers to the containment system for the cultivation of prokaryotic cells, while a bioreactor grows the eukaryotic cells (mammalian, insect cells, etc).
This presentation gives all the required information about pack bed bioreactor, including, advantages, disadvantages, applications and even how to overcome the disadvantages. Packed bed bioreactor is the major type of bioreactor used in waste water treatment as it involves the usage of catalyst. There are different types of packed bed bioreactors and they are used according to the desired product. There is picture representation and also tabular form of differentiation.
I have also mentioned the references at the end.
A bioreactor is an installation for the production of microorganisms outside their natural but inside an artificial environment. The prefix “photo” particularly describes the bio-reactor's property to cultivate phototrophic microorganisms, or organisms which grow on by utilizing light energy.
These organisms use the process of photosynthesis to build their own biomass from light and carbon dioxide. Members of this group are Plants, Mosses, Microalgae, Cyanobacteria and Purple Bacteria.
Photobioreactor or PBR, is the controlled supply of specific environmental conditions for respective species.
Photobioreactor allows much higher growth rates and purity levels than anywhere in natural or habitats similar to nature.
The function of the bioreactor is to provide a suitable environment in
which an organism can efficiently produce a target product—the target product might be.
Cell biomass
Metabolite
Bioconversion Product
The performance of any bioreactor depends on the following key factors:
Agitation rate
Oxygen transfer
pH
Temperature
There is no universal bioreactor.
The general requirements of the bioreactor are as follows:
The design and construction of bioreactors must keep sterility from the start point to end of the process.
Optimal mixing with low, uniform shear.
Adequate mass transfer, oxygen.
Clearly defined flow conditions.
Feeding substrate with prevention of under or overdosing.
Suspension of solids.
Gentle heat transfer.
Compliance with design requirements such as: ability to be sterilized; simple construction; simple measuring, control, regulating techniques; scale-up; flexibility; long term stability; compatibility with up- downstream processes; antifoaming measures.
A fluidized bed reactor (FBR) is a type of reactor device that can be used to carry out a variety of multiphase chemical reactions.
In this type of reactor, a fluid (gas or liquid) is passed through a solid granular material (usually a catalyst possibly shaped as tiny spheres) at high enough velocities to suspend the solid and cause it to behave as though it were a fluid.
This process, known as fluidization, imparts many important advantages to the FBR.
As a result, the fluidized bed reactor is now used in many industrial applications
Batch and Continuous Sterilization of Media in Fermentation Industry Dr. Pavan Kundur
Continuous sterilization is the rapid transfer of heat to medium through steam condensate without the use of a heat exchanger. ... This is more efficient than batch sterilization because instead of expending energy to heat, hold, and cool the entire system, small portions of the inlet streams are heated at a time.
The heart of the fermentation or bioprocess technology is the Fermentor or Bioreactor. A bioreactor is basically a device in which the organisms are cultivated to form the desired products. it is a containment system designed to give right environment for optimal growth and metabolic activity of the organism.
A fermentor usually refers to the containment system for the cultivation of prokaryotic cells, while a bioreactor grows the eukaryotic cells (mammalian, insect cells, etc).
The following presentation is only for quick reference. I would advise you to read the theoretical aspects of the respective topic and then use this presentation for your last minute revision. I hope it helps you..!!
Fluidized Bed Reactor - Basic Mechanism, Mass Transfer in Fluidized Beds, Reaction Behaviour in a Fluidized Bed, Mole Balance on the Bubble, the Cloud, and the Emulsion, Advantages & Disadvantages, Current Applications of FBR.
The following presentation is only for quick reference. I would advise you to read the theoretical aspects of the respective topic and then use this presentation for your last minute revision. I hope it helps you..!!
Mayur D. Chauhan
The CAWT's Dr. Gordon Balch's presentation to the Alberta Onsite Wastewater Management Association (March 2015).
Emerging Technologies in Onsite Wastewater Treatment.
The ppt discusses about the design of bubble and airlift bioreactor. It also deals with their application, advantages and disadvantages. Pictorial representation of bioreactors are provided for better understanding of the bioreactors. It helps to gain knowledge on the different type of bioreactors
This is a presentation on agitation and mixing of fluids. Agitation is the heart of all chemical methods. Every production process require agitation. That's why it is very important to make sure that the agitation is properly handled in a process. In this presentation we are going to discuss about agitation of fluids only. It doesn't contain the whole thing but the basic ideas about agitation.
Chemical reaction engineering is that engineering activity which is concerned with the exploitation of chemical reactions on commercial scale.
The areas of different fields of science like:
Oil Refining
Pharmaceuticals
Biotechnology
Chemical Industries
Sustainable Development
Report on Types of fluid flow
fluid dynamics
Introduction
In physics, fluid flow has all kinds of aspects: steady or unsteady, compressible or incompressible, viscous or non-viscous, and rotational or irrotational to name a few. Some of these characteristics reflect properties of the liquid itself, and others focus on how the fluid is moving. Note that fluid flow can get very complex when it becomes turbulent. Physicists haven’t developed any elegant equations to describe turbulence because how turbulence works depends on the individual system whether you have water cascading through a pipe or air streaming out of a jet engine. Usually, you have to resort to computers to handle problems that involve fluid turbulence. Types of fluid flow:
Aerodynamic force
Cavitation
Compressible flow
Couette flow
Free molecular flow
Incompressible flow
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
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👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
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- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
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A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
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Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
2. Contents
Fluid Flow in Bioreactors.
Mixing in CSTR (Continuous Stir Reactor).
Mixing in Bubble Column Reactor.
Mixing in Airlift Reactor.
Mixing in Packed Bed Reactor.
Mixing in Trickle bed Reactor.
Mixing in Fluidised Bed Reactor.
3. INTRODUCTION
A fluid is a substance which undergoes
continuous deformation
when subjected to a shearing force .
A simple shearing force which causes thin
parallel plates to slide over each other,
as in a pack of cards.
Fluids in bioprocessing often contain suspended
solids , consist of more than one phase , and
have non Newtonian properties .
A shear force must be applied to produce
fluid flow.
4. Two physical properties are used to classify fluids .
VISCOSITY and DENSITY.
DENSITY : Compressible fluids and Incompressible fluids .
VISCOCITY : an ideal or perfect fluid is a hypothetical liq. Or
gas which is incompressible and has zero viscosity.
Inviscid fluids and viscid fluids.
fluids can also be classified further as Newtonian and
non Newtonian .
NEWTONIAN FLUIDS : which obeys the newton’s laws of
viscosity i.e.
t = mdv/dy ; where t = shear stress, m = viscosity of fluid,
dv/dy = shear rate, rate of strain or velocity gradient.
NON NEWTONIAN FLUIDS : which do not obey the
Newton's law of viscosity.
5. FLUIDS IN MOTION
When a fluid flows through pipe or over a solid object ,
the velocity of the fluid varies depending on position.
One way of representing variation in velocity is
streamlines,
which follow the flow path. Constant velocity is shown by
equidistant spacing of parallel streamlines . As in fig. 1.
Where as in fig . 2 there is a reducing space between
the streamlines indicates that velocity at top and bottom
of the object is greater than at the front and back.
Therefore ,
slow fluid flow is called STREAMLINE or LAMINAR
FLOW.
And in fast motion, fluid particles cross and recross the
streamline and the motion is called as TURBULENT
FLOW.
6. REYNOLDS NUMBER
A parameter used to characterise fluid flow .
For full flow in pipes with cross section , Reynolds number Re is :
Re = Duρ/μ ; where D is pipe diameter ,
u is the average linear velocity of the fluid,μ is fluid viscosity.
For a stirred vessel there is another definition of the Reynold no.
Rei = Ni Di² ρ / μ ; where Rei is the impeller Reynolds no. ,
Ni is the stirrer speed , ρ is the fluid density , Di is the impeller
diameter.
The Reynolds no. is a dimensionless variable .
Reynolds no. is named after OSBORNE Reynolds , who published in
1883
a classical series of papers on the nature of flow in pipes.
7. NON NEWTONIAN FLUIDS
Most slurries , suspensions
and dispersions are non
Newtonian .
Many fermentation
processes involve materials
which exhibit non
Newtonian behaviour , such
as starches, extracellular
polysaccharides ,and culture
broth containing cell
suspensions or pellets.
8.
9. HYDRODYNAMIC BOUNDARY
LAYERS
The part of the fluid where flow is affected by the solid is called the
‘’ boundary layer ‘’.
Contact between moving fluid and the plate causes the
formation of the boundary layer beginning at the leading
edge and developing on both top and bottom of plate.
When fluid flows over a stationary object , a thin film of
fluid in contact with the surface adheres it to prevent
slippage over the surface. fluid velocity at the surface
of the plate in fig 7.3 b is therefore zero.
When a part of flowing fluid has been brought to rest ,
the flow of adjacent fluid layers is slowed down by the
action of ‘ viscous drag ‘ .
Compared with velocity uB in the bilk fluid , velocity in the
boundary layer is zero at the plate surface but increases
with distance from the plate to reach uB near the outer limit
of boundary layer .
10. BOUNDARY LAYER SEPERATION
What happens when contact is
broken between a fluid and a solid
immersed in
the flow path ?
when fluid reaches the top or
bottom of the plate its momentum
prevents it from
making the sharp turn around the
edge . As a result fluid separates from
the plate
and proceeds outwards into the
bulk fluid .
11. Stir Tank Reactor
The continuous stirred-tank
reactor, also known back mix
reactor, is a common ideal
reactor type in chemical
engineering.
A CSTR often refers to a model
used to estimate the key unit
operation variables when using a
continuous agitated-tank reactor
to reach a specified output.
12. Mixing Method
Mixing method:
Mechanical agitation
• Baffles are usually used
to reduce vortexing
• Applications: free and
immobilized enzyme
reactions
• High shear forces may
damage cells
• Require high energy
input
13. An ideal CSTR has complete back -mixing
resulting in a minimisation of the substrate
concentration, and a maximisation of the
product concentration, relative to the final
conversion, at every point within the reactor
the effectiveness factor being uniform
throughout. Thus, CSTRs are the preferred
reactors, everything else being equal, for
processes involving substrate inhibition or
product activation. They are also useful
where the substrate stream contains an
enzyme inhibitor, as it is diluted within the
reactor. This effect is most noticeable if the
inhibitor concentration is greater than the
inhibition constant and [S]0/Km is low for
competitive inhibition or high for
uncompetitive inhibition, when the inhibitor
14. Bubble column Bioreactor
A bubble column reactor is an apparatus
used for gas-liquid reactions first
applied by Helmut Gerstenberg.
It consists of vertically arranged
cylindrical columns. The introduction
of gas takes place at the bottom
of the column and causes a turbulent
stream to enable an optimum gas
exchange.
In BCR, gas & liquid reactants are
compacted in presence of finely
dispersed catalyst are used in different
applications from fermentations to
production of chemicals &
pharmaceuticals. They have high
volumetric productivity & excellent heat
15. Mixing
Bubble column reactors are widely used to
carry out multi-phase reactions. Mixing and
transport processes are the key issues in the
design of bubble columns, especially for
processes involving multiple reactions where
selectivity to the desired product is important.
Under such circumstances, liquid phase
mixing often decides the reactor performance.
The local flow field and turbulence governs the
fluid mixing and is interrelated in a complex
way with the design and operating parameters.
16. Mixing
Both axial and radial mixing are possible in
bubble column reactor. Mixing in axial
direction is a function of aeration rate,
geometry of the column and the properties
of the fluid. Rising gas bubbles carry
elements of circulating fluid in bubble wakes
produce axial mixing. Because bubble rises
faster than the liquid, a certain amount of
liquid is carried forward faster than the bulk
flow of the liquid. This produces mixing in
the axial direction.
For tubular reactors, axial mixing is usually
several times higher than radial mixing.
Thus, for most practical purposes, attention
is focused only on axial mixing.
In case of radial mixing, bubbles may
impinge on the walls of the reactor and
break consequently with improvement of
mass transfer.
17. Airlift reactor
Air-lift bioreactors are similar to
bubble column reactors, but differ
by the fact
that they contain a draft tube.
The draft tube is always an inner
tube
or an external tube .This kind of
air-lift bioreactor is called "air-lift
bioreactor
with an external loop” which
improves circulation and oxygen
transfer and
equalizes shear forces in the
reactor.
18. Mixing
Mixing method: Airlift
• In these reactors mixing circulation and
aeration is performed by gas injection and if
needed by additional external liquid
circulation to obtain the required mixing
pattern. The figure, gives an example of a
possible configuration. This usually results in
less shear for a given quality of mixing than in
stirred tanks. Air lifts give more vigorous
recirculation for the same air flow, but often
lower oxygen transfer rates than bubble
columns. To limit shear, small bubbles can be
used in aeration, but depending on conditions
this may cause excessive foaming and
requires more energy for their generation at
porous distributors.
19. Packed-bed reactor
Packed-bed reactors are
used with immobilized or
particulate biocatalysts.
Medium can be fed either
at the top or bottom and
forms a continuous liquid
phase. The advantage of
using a packed bed reactor
is the higher conversion per
weight of catalyst than
other catalytic reactors. The
conversion is based on the
amount of the solid catalyst
rather than the volume of
the reactor.
20. Mixing
In packed bed reactors, cells are
immobilized on large particles. These
particles do not move with the liquid.
Packed bed reactors are simple to
construct and operate but can suffer
from blockages and from poor oxygen
transfer.
Continuous packed bed reactors are
the most widely used reactors for
immobilized enzymes eg.
Amiloglucosidase and immobilized
microbial cells. In these systems, it is
necessary to consider the pressure
drop across the packed bed or column,
and the effect of the column
dimensions on the reaction rate.
21. Trickle-bed reactor
The trickle-bed reactor is another
variation of the packed bed reactors.
Liquid is sprayed onto the top of the
packing and trickles down through
the bed in small rivulets.
It is considered to be the simplest
reactor type for performing catalytic
reactions where a gas and liquid
(normally both reagents) are present
in the reactor and accordingly it is
extensively used in processing plants.
22. Mixing
In a trickle bed reactor the liquid and gas phases flow
concurrently downwards through a fixed bed of catalyst
particles while the reaction takes place. In certain cases,
the two-phases also flow concurrently upwards. The
concurrent upward flow operation provides better radial
and axial mixing than the downward flow operation, thus
facilitating better heat transfer between the liquid and
solid phases. This is highly useful in exothermic reactions
where heat is required to be removed continuously from
the reactor. However, due to higher axial mixing in the
upward flow operation, the degree of conversion, a
crucial factor in the operation is preferred. Because of
lower axial mixing, better mechanical stability and less
flooding is achieved , thus facilitating processing of
higher flow rates and increased reactor capacity.
23. Flow Regimes
Trickle bed reactors operate in a variety of
flow regimes ranging from gas-continuous
to liquid-continuous patterns. They usually
fall into two broad categories referred to as
low interaction regime (trickle flow regime)
and high interaction regime (pulse, spray,
bubble and dispersed bubble flow regimes).
The low interaction regime is observed at
low gas and liquid flow rates and is
characterized by a weak gas-liquid
interfacial activity and a gravity-driven
liquid flow. High interaction regime is
characterized by a moderate to intense gas-
liquid shear due to moderate to high flow
rate of one or both of the fluids. As a result,
various flow patterns arise depending on the
gas and liquid flow rates and the physical
properties of the liquid.
Schematic diagram of the trickle flow
24. Fluidized bed reactor
Fluidized bed reactor (FBR) is a type
of reactor device that can be used to
carry out a variety
of multiphase chemical reactions. In this
type of reactor, a fluid (gas or liquid)
is passed through a granular solid
material (usually a catalyst possibly
shaped as tiny spheres) at high
enough velocities to suspend the solid
and cause it to behave as though it were
a fluid. This process, known
as fluidization, imparts many important
advantages to the FBR.
25. Mixing
The solid substrate (the catalytic material
upon which chemical species react) in the
fluidized bed reactor is typically supported
by a porous plate, known as a
distributor. The fluid is then forced through
the distributor up through the solid material.
At lower fluid velocities, the solids remain in
place as the fluid passes through the voids
in the material. As the fluid velocity is
increased, the reactor will reach a stage
where the force of the fluid on the solids is
enough to balance the weight of the solid
material. This stage is known as incipient
fluidization and occurs at this minimum
fluidization velocity. Once this minimum
velocity is surpassed, the contents of the
reactor bed begin to expand and swirl
around much like an agitated tank or boiling
pot of water. The reactor is now a fluidized
26. References
NChE Journal (Vol. 21, No. 2)
Wikipedia
Braz. J. Chem. Eng. vol.31 no.1 São
Paulo Jan./Mar. 2014
Trans IChemE, Part A, Chemical Engineering
Research and Design, 2004, 82(A10): 1367–
1374
N. Kantarci et al. / Process Biochemistry 40
(2005) 2263–2283