CHEMMAT 303 Chemical Reactor Engineering - Course Outlines

Course Prescription

Kinetics of multiple reactions, analysis of basic reactors – batch, plug flow, and continuous stirred tank. Performance under isothermal, adiabatic, and varying temperature. Effect of semi-continuous, counterflow and recycle on performance. Heterogeneous reactions and catalysis, diffusion and reaction in porous catalysts, effects of external mass transfer resistance, fixed and fluidised bed reactors, gas-liquid reactors. Reactor engineering for biological and electrochemical systems.

Course Overview

Programme:

Total of 36 hours lectures, 3 x 2 hours laboratories.

Starting knowledge required:

It is expected that all students have at least entry university level knowledge of mathematics in order to be comfortable with the use of differential calculus in various situations and to be able to perform simple mathematical analytical and numerical derivation/integration.

The students should have been previously exposed with the concepts of material and energy balances and should be able to apply these in unfamiliar circumstances. The students should also have some knowledge of fluid dynamics and thermodynamics for an appreciation of fluid flow, reaction equilibria, heats of reaction, and energy balances.

Scope:

This course consists of two main parts:

1. In the first part of this course, all reactions are presented as being homogeneous reactions and reaction rates are always presented as being volume specific.

As some students may not have come across reaction kinetics before, this part will start with a short introduction, which, will give a definition to the three fundamental reactor types used in reaction engineering and show how material balances should be performed for them. We will investigate how these material balances can be used to design reactors by calculating their volume or residence time. During the course, 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 understand that reactors do not need to 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. As a result, this will be used to allow us to calculate reactor volumes and residence times for a given duty. We will discuss non-ideal reactors; this is intended to illustrate the limitations of always assuming that reactors behave in an ideal manner. This section includes the calculation of the residence time required for attaining the desired conversion of solid reactant in a PFR and CSTR with a simple distribution of particle sizes.

2. In the second part of this course, all reactions are presented as being heterogeneous reactions, which is in turn divided into main sub-categories: catalytic and non-catalytic. In the case of catalytic reactions, the reaction rates are presented in different expressions but mainly being specific to the mass of catalyst used.

This part will start with a short introduction to define a heterogeneous reaction and explain its types. Conversion between different bases used for reaction rate expressions is essential to derive the overall rate of reaction for an in-series linear process and to explain the difference between the true and overall rate of reaction. Following this introduction, the course will proceed with explaining the seven steps in a heterogeneous catalytic reaction. This includes the inter-dependence interaction between mass transfer & reaction, rate limiting step, and development of mass balance over a catalytic pore.

The cacluation part starts with modelling internal and external steps in heterogeneous catalysis and estimating Thiele Modulus and internal effectiveness factor in a single pore of catalyst for a first order reaction. Once the main formulae being derived, it can be further extended to cover the concentration gradient in the entire catalyst particle and to apply the generalized Thiele Modulus. We will explain how non-isothermal behavior (exothermic or endothermic) affects the rate of heterogeneous catalytic reactions.

Advantages and disadvantages of different types of heterogeneous reactors will be discussed to perform calculations of conversion in a packed bed, fluidized bed, continuously stirred and batch reactor. In this frame, applications of Carman-Kozeny equation and Ergun equation will be presented to describe laminar and turbulent flow through randomly packed particles. This explanation will help to calculate particle size and specific surface area of particles, rate of flow of fluid through a packed bed, pressure drop to drive fluid through a packed bed, the superﬁcial liquid velocity at incipient ﬂuidization, and minimum and maximum flow rate in a fluidized bed, reactor diameter and height for fluidization operations.

We shall define the activity of a catalyst and explain the different mechanisms behind catalyst deactivation and which are reversible through catalyst regeneration. The calculation part here includes the catalyst deactivation rate, and how this affects reactor performance, the conversion of a reactant in presence of deactivation and the run time for one cycle of catalyst deactivation. We shall also contrast and compare models to describe fluid-solid non-catalysed reactions.

Course Requirements

Prerequisite: CHEMMAT 202 and 206, or CHEMMAT 212 and 242 Restriction: CHEMMAT 315

Learning Outcomes

By the end of this course, students will be able to:

Explain the principles of reaction engineering including reaction kinetics, stoichiometry, reversible reaction, mass and heat transfer in industrial-scale reactors (Capability 3.1)
Develop design equations for batch reactors, continuous stirred tank reactors and plug flow reactors for single, multiple parallel and series reactions under different conditions of adiabatic and non-isothermal operations (Capability 3.1 and 4.1)
Conclude optimum design of reactors through a comparison between different classification given any set of reaction kinetics in real-industrial problems (Capability 4.1)
Identify the similarity and differences between ideal and real reactors, performance, residence time distribution and its effect on chemical conversion (Capability 3.1)
Define heterogeneous reactions based on different classifications, reaction rate expressions, difference between true and observed rates, deriving overall rate of reaction for in-series linear processes. (Capability 3.1 and 4.1)
Estimate internal and external effects of mass transfer, Thiele modulus, Wagner-Weisz-Wheeler modulus, observed rates of reactions, effect of catalyst size and shape, in both isothermal and non-isothermal effect. (Capability 3.1 and 4.1)
Explain different types and mechanisms of catalyst deactivation, and their effect on reactor performance based on reactant conversion and catalyst life-time (Capability 4.1 and 5.1)
Derive and compare the models being used to describe gas solid non-catalytic reactions, namely shrinking core model and progressive core model. (Capability 4.1)
Demonstrate practical proficiency in laboratory of chemical reactor engineering. (Capability 4.2)

Assessments

Assessment Type	Percentage	Classification
Final Exam	50%	Individual Examination
Laboratories	20%	Individual Coursework
Tests	20%	Individual Test
Assignments	10%	Individual Coursework
4 types	100%

Assessment Type	Learning Outcome Addressed
	1	2	3	4	5	6	7	8	9
Final Exam
Laboratories
Tests
Assignments

Workload Expectations

This course is a standard 15 point course and students are expected to spend 10 hours per week involved in each 15 point course that they are enrolled in.

For this course, you can expect 36 hours of lectures (3 Lec/wk), 6 hours of laboratory work, 50 hours of reading and revision and 58 hours of work on reports, tests and examination preparation. Attending the labs is a compulsory in this course.

Delivery Mode

Campus Experience

Attendance is required at scheduled activities including labs to complete components of the course.

Lectures will be available as recordings. Other learning activities including tutorials and labs will not be available as recordings.

The course will not include live online events including group discussions/tutorials.

Attendance on campus is required for the tests and exam.

The activities for the course are scheduled as a standard weekly timetable.

Learning Resources

Course materials are made available in a learning and collaboration tool called Canvas which also includes reading lists and lecture recordings (where available).

Please remember that the recording of any class on a personal device requires the permission of the instructor.

Textbook:

• Chemical Reaction Engineering, 3rd edition, O. Levenspiel, J Wiley & Sons.

• Elements of Chemical Reaction Engineering, 3rd edition, S. Fogler, Prentice Hall.

Additional Textbook:

• Chemical Engineering Kinetics J.M. Smith, McGraw-Hill

Health & Safety

Students are expected to adhere to the guidelines outlined in the Health and Safety section of the Engineering Undergraduate Handbook, including risk management and safety induction for laboratory work.

Student Feedback

At the end of every semester students will be invited to give feedback on the course and teaching through a tool called SET or Qualtrics. The lecturers and course co-ordinators will consider all feedback and respond with summaries and actions.

Your feedback helps teachers to improve the course and its delivery for future students.

Class Representatives in each class can take feedback to the department and faculty staff-student consultative committees.

According to the students' feedback, no change is required for assessment methods and the course content. The labs will be conducted two weeks before the mid-semester break starts. This reduces the student’s overall workload from other papers towards the end of the semester.

Academic Integrity

The University of Auckland will not tolerate cheating, or assisting others to cheat, and views cheating in coursework as a serious academic offence. The work that a student submits for grading must be the student's own work, reflecting their learning. Where work from other sources is used, it must be properly acknowledged and referenced. This requirement also applies to sources on the internet. A student's assessed work may be reviewed for potential plagiarism or other forms of academic misconduct, using computerised detection mechanisms.

Class Representatives

Class representatives are students tasked with representing student issues to departments, faculties, and the wider university. If you have a complaint about this course, please contact your class rep who will know how to raise it in the right channels. See your departmental noticeboard for contact details for your class reps.

Inclusive Learning

All students are asked to discuss any impairment related requirements privately, face to face and/or in written form with the course coordinator, lecturer or tutor.

Student Disability Services also provides support for students with a wide range of impairments, both visible and invisible, to succeed and excel at the University. For more information and contact details, please visit the Student Disability Services’ website http://disability.auckland.ac.nz

Special Circumstances

If your ability to complete assessed coursework is affected by illness or other personal circumstances outside of your control, contact a member of teaching staff as soon as possible before the assessment is due.

If your personal circumstances significantly affect your performance, or preparation, for an exam or eligible written test, refer to the University’s aegrotat or compassionate consideration page https://www.auckland.ac.nz/en/students/academic-information/exams-and-final-results/during-exams/aegrotat-and-compassionate-consideration.html.

This should be done as soon as possible and no later than seven days after the affected test or exam date.

Learning Continuity

In the event of an unexpected disruption, we undertake to maintain the continuity and standard of teaching and learning in all your courses throughout the year. If there are unexpected disruptions the University has contingency plans to ensure that access to your course continues and course assessment continues to meet the principles of the University’s assessment policy. Some adjustments may need to be made in emergencies. You will be kept fully informed by your course co-ordinator/director, and if disruption occurs you should refer to the university website for information about how to proceed.

Student Charter and Responsibilities

The Student Charter assumes and acknowledges that students are active participants in the learning process and that they have responsibilities to the institution and the international community of scholars. The University expects that students will act at all times in a way that demonstrates respect for the rights of other students and staff so that the learning environment is both safe and productive. For further information visit Student Charter https://www.auckland.ac.nz/en/students/forms-policies-and-guidelines/student-policies-and-guidelines/student-charter.html.

Disclaimer

Elements of this outline may be subject to change. The latest information about the course will be available for enrolled students in Canvas.

In this course students may be asked to submit coursework assessments digitally. The University reserves the right to conduct scheduled tests and examinations for this course online or through the use of computers or other electronic devices. Where tests or examinations are conducted online remote invigilation arrangements may be used. In exceptional circumstances changes to elements of this course may be necessary at short notice. Students enrolled in this course will be informed of any such changes and the reasons for them, as soon as possible, through Canvas.

Capability 3:	Knowledge and Practice
Capability 4:	Critical Thinking
Capability 5:	Solution Seeking

CHEMMAT 303 : Chemical Reactor Engineering

Engineering

2024 Semester Two (1245) (15 POINTS)