Newcastle University

Aims

At the end of the course the students should be able to describe chemical reactors using models. They should be aware of the limitations of ideal reactor models and be able to compare models and then choose a reactor model which is of sufficient complexity to give an answer of the required accuracy.

We start by showing how material balances should be performed for the three fundamental reactor types used in reaction engineering, namely the plug-flow reactor (PFR), the continuous stirred tank reactor (CSTR) and the perfectly-mixed batch reactor. We will see how these material balances can be used to design (by this we primarily mean how to calculate their volume or residence time) reactors when one reaction is taking place. We will also compare the behaviour of the different reactors. We will proceed to look at how the design process must be modified when more than one reaction is occurring. We will see that reactors need not be isothermal. Therefore, we need to look at how reaction rate depends upon temperature for different classes of reaction. Then we will formulate the energy balance for given reactors and use this to investigate the variation of temperature and therefore reaction rate with time or position in the reactor. This in turn will be used to allow us to calculate reactor volumes and residence times for a given duty. In the final section, there is a brief discussion of non-ideal reactors; this is intended to illustrate the limitations of always assuming that reactors behave in an ideal manner.

Original Summary:
Reactors
Introduction to batch and continuous reactor operation, batch reactor design equation, Example 2.1a
Plug flow reactor design equation, Example 2.2a
CSTR design equation, Example 2.3a

Single reactions
Constant pressure and constant volume batch reactors, Example 3.1a
Plug flow reactors, Example 3.2a
Problem class on PFRs
CSTRs
Comparison of PFR and CSTR and CSTRs in series, Example 3.4a
Similarity between series of CSTRs and PFR
Recycle reactor, Example 3.7a

Multiple reactions
Introduction to multiple reactions, parallel reaction of the same order, Parallel Reactions Example
Parallel reactions of different orders, Example 4.3a
Problem class on parallel reaction of different orders
Consecutive reactions, Example 4.4a

Energy balance
Effect of temperature on reaction rate
Forms of the energy balance
PFR energy balance
CSTR energy balance
Energy balance problem class

Non ideal reactors
Non-ideal reactors, RTDs, Example 6.1, Calculation of conversion from RTD, Example 6.2

Outline Of Syllabus

N/A

Teaching Rationale And Relationship

Lectures introduce theoretical concepts that will be practiced in tutorials. The case study provides an opportunity to apply knowledge gained together with knowledge from other modules, to solve a realistic problem.

Assessment Rationale And Relationship

Examination assesses the knowledge and skills gained on closed problems where all necessary information is supplied. Case study assesses the skills obtained on open-ended problems where students must consider what information is needed to achieve a solution.