# MASS AND ENERGY BALANCES - 2021/2

Module code: ENG1081

## Module Overview

The conservation of both Mass and Energy are fundamentals on which all Chemical Processing is based.  Being able to properly formulate and solve material and energy balances and in so doing integrate and interpret physical property data from different sources and in a variety of different units is an essential skills for an engineer.   The module covers the fundamental concept used when analysing the mass and energy flows in chemical processing and allows students to apply them to the analysis of a wide variety of real-world situations.

### Module provider

Chemistry and Chemical Engineering

LEE Judy (Chm Proc Eng)

### Module cap (Maximum number of students): N/A

Independent Learning Hours: 96

Lecture Hours: 11

Tutorial Hours: 11

Guided Learning: 10

Captured Content: 22

Semester 1

None.

## Module content

Indicative content includes:

Background               Definitions of relevant quantities and properties.

Units, systems of units and unit conversion – Tutorial Sheet 1

Ideal Gas Laws          Ideal gases, Dalton’s and Amagat’s Laws, Ideal gas mixtures – Tutorial Sheet 2

Vapours                     Single component vapour-liquid-solid equilibrium, critical point, triple point

Saturated vapour pressure, Antoine equation

Raoult’s Law, saturation – Tutorial Sheet 3

Energy                        Energy changes associate with temperature and phase changes

Ideal component heat capacity, enthalpy and internal energy – Tutorial Sheet 4

Enthalpy of formation, reaction enthalpy, equilibrium  – Tutorial Sheet 5

Gibbs Phase Rule     Formulation and application

Material Balances (1)            Definition of system, Basis and formulation of overall and component balances, special equipment dependent balances

Basis and formulation of solution, independent equations and variables

Balances without phase change or reaction – Tutorial Sheet 6

Balances with phase change, and with phase change and reaction –  Tutorial Sheet 7

Fuel and Combustion Calculations            Fuel and combustion reactions, energy released (gross and net CV)

Fuel Calculations – Tutorial Sheet 8

Material Balances (2)            Recycle, purge and bypass and associated balances – Tutorial Sheet 9

Stream Enthalpy Calculations        Enthalpy datum, single phase and two phase streams, “Wise Students Guide to Stream Enthalpy Calculations” – Tutorial Sheet  10

Multiphase stream enthalpy calculations – Tutorial Sheet 11

Energy Balances       Steady state energy balances

Energy balances with and without phase change but without reaction

Energy balances with phase change and reaction – Tutorial Sheet 12

## Assessment pattern

Assessment type Unit of assessment Weighting
Online Scheduled Summative Class Test ONLINE (OPEN BOOK) TEST 20
Examination Online ONLINE (OPEN BOOK) EXAM 80

None

## Assessment Strategy

The assessment strategy is designed to provide students with the opportunity to demonstrate the full range of learning outcomes through the balanced mixture of lecture and tutorial/problem classes coupled with the carefully grades tutorial problems which reflect current industrial practice.

Thus, the summative assessment for this module consists of:

• Class Test – 20%, material covered is the first 5 sections of the module (LO1, LO2, LO3)

• Examination – 80%, 2 hours (LO1, LO2, LO3, LO4, LO5, LO6)

Formative assessment

None

Feedback

Weekly verbal feedback will be given during tutorial classes.

Written feedback on the Class Test

## Module aims

• A systematic appreciation of the principles used to establish material and energy balances for chemical processes.
• An opportunity to extensively practice the techniques of solving material and energy balances in a supportive environment.

## Learning outcomes

 Attributes Developed 1 Recognise the foundations of different unitary systems and fluently convert quantities between them. KC 2 Explain the Ideal Gas laws and confidently analyse systems containing ideal gas mixtures C 3 Confidently use saturated vapour pressure data to analyse single component vapour-liquid equilibrium and using Raoult's Law and Gibbs Phase Rule extend this analysis to multicomponent liquid/gas/vapour systems KCP 4 Demonstrate an ability to formulate a solution to and then solve process material balances which may involve any combination of the following: reactions, multiple phases, multiple series or parallel process units, recycles/bypass/purge. KC 5 Recognise the need for and be able to accurately calculate process energy balances. KC 6 To confidently integrate process material and energy balances for both reactive and non-reactive systems with and without phase change KCP

Attributes Developed

C - Cognitive/analytical

K - Subject knowledge

T - Transferable skills

P - Professional/Practical skills

## Methods of Teaching / Learning

The learning and teaching strategy is designed to:

• Carefully cover in lectures the necessary fundamental material and analytical techniques demonstrating each with appropriate examples

• Allow students adequate time to practice the techniques using a large number of carefully selected tutorial problems (NOTE – In order to become proficient in solving material and energy balances it is necessary that students devote sufficient time to properly solving all the tutorial problems presented.)

The learning and teaching methods include:

• Lectures                                 4 hours per week for 11 weeks

• Tutorial/Problem Classes       1 hour per week for 12 weeks

• Independent learning              7.8 hours per week for 12 weeks (average)

Indicated Lecture Hours (which may also include seminars, tutorials, workshops and other contact time) are approximate and may include in-class tests where one or more of these are an assessment on the module. In-class tests are scheduled/organised separately to taught content and will be published on to student personal timetables, where they apply to taken modules, as soon as they are finalised by central administration. This will usually be after the initial publication of the teaching timetable for the relevant semester.