This document discusses different types of continuous flow reactors used in industrial processing. It describes continuous stirred tank reactors (CSTR), plug flow reactors, and tubular flow reactors. CSTRs mix reactants continuously and are commonly used in fermentation and liquid reactions requiring agitation. Plug flow reactors consist of a tube where reactants flow without mixing and have higher efficiency than CSTRs. Tubular flow reactors also flow reactants through a tube but may have a varying diameter and gradient of concentrations along the flow path.
2. CONTINUOUS REACTORS
•Reactants are added and
products removed
continuously at a constant
mass flow rate. Large daily
product rates are mostly
conducted in continuous
equipment.
4. CSTR
• A continuous stirred tank reactor (CSTR)
is a vessel to which reactants are added
and products removed while the contents
within the vessel are vigorously stirred
using internal agitation or by internally
(or externally) recycling the contents.
• CSTRs may be employed in series or in
parallel.
5. CSTR
• Residence time – average amount of time
a discrete quantity of reagents spend
inside the tank
• Residence time = volumetric flow rate
volume of the tank
• At steady state,the flow rate in must be
equal the mass flow rate out.
7. CSTR APPLICATIONS
• Continuous stirred – tank reactors are most
commonly used in industrial processing, primarily
in homogeneous liquid-phase flow reactions,
where constant agitation is required. They may be
used by themselves , in series , or in a battery.
• Fermentors are CSTRs used in biological processes
in many industries, such as brewing, antibiotics,
and waste treatment.in fermenters, large molecules
are broken down into smaller molecules, with
alcohol produced as a by-products.
8. ADVANTAGES/DISADVANTAGES
OF CSTR
•Good temperature control is easily
maintained
•Cheap to construct
•Reactor has large heat capacity
•Interior of reactor is easily accessed
Disadvantage:
•Conversion of reactant to product per
volume of reactor is small compared
9. PLUG FLOW REACTOR
•Plug flow , or tubular , reactors
consist of a hollow pipe or tube
through which reactants flow .
Pictured below is a plug flow
reactor in the form of a tube
wrapped around an acrylic mold
which is encased in a tank. Water
at a controlled temperature is
10. PLUG FLOW REACTOR
•Reagents may be introduced into
the reactors inlet
•All calculations performed with
PFRs assume no upstream or
downstrem mixing.
•Has a higher efficiency than a CSTR
at the same value.
12. APPLICATIONS OF PLUG FLOW
REACTOR
•Plug flow reactors have a wide variety
of applications in either gas or liquid
phase systems. common industrial
uses of tubular reactors are in
gasoline production, oil cracking,
synthesis of ammonia from its
elements, and the oxidation of sulfur
dioxide to sulfur trioxide.
13. TUBULAR FLOW REACTORS
• A tubular flow reactor (TFR) is a tube (or pipe)
through which reactants flow and are converted
to product.
• The TFR may have a varying diameter along the
flow path.
• In such a reactors, there is a continuous gradient
(in contrast to the stepped gradient characteristic
of a CSTR-inseries battery ) of concentration in
the direction of flow.
• Several tubuler reactors in series or in parallel
may also be used. Both horizontal and vertical
14. TUBULAR FLOW REACTORS
•Chemical reactions take place in a
stream of gas that carries reactants
from the inlet to the outlet
•The catalysts are in tubes uniform
loading is ensured by using special
equipment that charges the same
amount of catalyst to each tube at a
definite rate.
