Reactor Continuous stirred tank reactor CSTR

The document describes different types of reactors used in chemical processes. It discusses batch reactors,

1. Kinetics and Reactor Design Design and operation of CSTR Chapter 3

2. 2 Introduction

3. 3 Chemical Reactions and Rate of Reactions: The rate equation (i.e. rate law) is an algebraic equation that is solely a function of the properties of the reacting materials and reaction conditions including species, temperature, pressure or type of catalyst, if any at a point in the system. Reaction rate definition is independent of reactor type. Rate of reaction is change of concentration with respect to time! Mathematically, it can be represented as: Dimension: Units: where k (T ) is a function of temperature. The rate law must be determined experimentally. The common form of the rate law is: − r A = kC A a C B b Rate constant dimension (K)   n= a+b   Units:  

4. 4 Relative Rates of Reaction It is defined for each species in the chemical reaction, i.e. - -

5. 5 Extent of Reaction (Mass balance calculations) This can also be written in terms of a molar flow as, n i = n i,0 + ν i ξ . . The ratio of the change in the number of moles present, d N i , to the stoichiometric coefficient, ν i , for the reactant is the same in each case, and this ratio is called the extent of reaction, ξ, N i = N i,0 + ν i ξ

6. 6 Conversion

7. 7 General Mole Balance for Reactors

8. 8 Continuous Stirred Tank Reactor (CSTR): Definition: Continuous Stirred Tank Reactors (CSTR) are defined to be flow reactors characterized by intense mixing so that the properties anywhere inside the reactor are exactly the same as that of the exist stream. Input Rate Liquid Surface V Stirrer Schematic Representation of CSTR: Output Rate Assumptions : Steady state Well-mixed

9. 9 Continuous Stirred Tank Reactor (CSTR): 1- Steady state: No accumlation dNi / dt =0

10. 10 Continuous Stirred Tank Reactor (CSTR):

11. 11 Continuous Stirred Tank Reactor (CSTR):

12. 12 Continuous Stirred Tank Reactor (CSTR):

13. 13 Continuous Stirred Tank Reactor (CSTR):

14. 14 Thank you