Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.



No description

salah ali

on 11 October 2013

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of CSTR REACTOR

Introduction of CSTR REACTOR
To describe the dynamic behavior of a CSTR mass, component and energy balance equations must be developed. This requires an understanding of the functional expressions that describe chemical reaction.

Usage examples ofCSTR
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.

Introduction of CSTR REACTOR
CSTR Reactor is used in prepolymerization process in polystyrene plant
Introduction of CSTR REACTOR
The continuous stirred-tank reactor (CSTR), also known as vat- or back mix reactor is a common ideal reactor type in chemical engineering.

Introduction of CSTR REACTOR
Continuous stirred-tank reactors (CSTR) are open systems, where material is free to enter or exit the system.

Introduction of CSTR REACTOR
CSTR are very well mixed, so the contents have relatively uniform properties such as temperature, density, etc.
Introduction of CSTR REACTOR
Multiple CSTR can also be used when two immiscible liquids or viscous liquids are present and require a high agitation rate.
Stirring blades,also called agitators,are used to mix the reactants. Below are pictures of various agitators that could be used inside a CSTR.

Mole Balance on Reactor 2

Characteristics Continuously Stirred Tank Reactor (CSTR)
Kinds of Phases Present :
1. Liquid phase
2. Gas-liquid
3. Solid-liquid

Characteristics Continuously Stirred Tank Reactor (CSTR)
Usage :
When agitation and good mixing are required .

Characteristics Continuously Stirred Tank Reactor (CSTR)
Advantages :
1.Continuous operation
2.Good temperature control
3.Easily adapts to two phase runs
4.Good control
5.Simplicity of construction
6.Low operating cost
7.Easy to clean
Characteristics Continuously Stirred Tank Reactor (CSTR)
Disadvantages :
Conversion of reactant to product per volume of reactor is small compared to other flow reactors
Sizing of CSTR
To derive the CSTR sizing equation,we begin with the general mole balance :

Sizing of CSTR
Writing the mole balance expression for a stirred tank:
Consider a well-mixed tank of liquid. The inlet stream flow is FAO (m3/s) with density ρin (kg/m3). The volume of the liquid in the tank is V (m3) with constant density ρ (kg/m3). The flow leaving the tank is FA (m3/s) with liquid density ρ (kg/m3).

Sizing of CSTR
1) Steady state therefore

2) Well mixed therefore rA is the same throughout the reactor

Rearranging the generation

-rA = kCA where k=constant and CA=molar concentration (mole/dm3)
From the definition of conversion, FA = FAo (1-X) or FAo - FA = FAoX, so the equation can be rewritten:

Sizing of CSTR
Given rA and FAO and x, one can size any type of CSTRreactor.

Sizing of CSTR(Reactors in Series)
One can also design any sequence of reactors in series provided there are no side streams by defining the overall conversion at any point.

Sizing of CSTR(Reactors in Series)
Mole Balance on Reactor 1:
Sizing of CSTR(Reactors in Series)
Mole Balance on Reactor2 :
Full transcript