Joint Chemical Engineering Committee
Technical Meeting
Design Processes for Least Energy Waste
DATE & TIME
th
Tuesday 30 August 2016
5.30pm for 6pm start
Light refreshments will be
served
VENUE
CPD
Engineers Australia Auditorium
Ground Floor, 8 Thomas Street
Chatswood NSW 2067
Eligible for 1 Continuing
Professional Development hour
REGISTRATION FEE
(incl. GST)
REGISTRATIONS CLOSE
26th August 2016
EA & IChemE members - Free
Students - Free
Non-members $30
Topic: Designing processes for least energy waste using a new thermodynamic technique
In this talk Prof. Glasser will present a way to assess the energy requirements of a process that gives the
feasible constraints of the process with a view to minimising its energy consumption. A key feature of the
approach is the appearance of the energy term work which has been typically neglected unlike the more
familiar energy term, heat. It is here that (change in) Gibbs Free Energy is used to express the totality of
work as the sum of heat, as enthalpy, mechanical work (e.g. as compression) and chemical potential.
Chemical processes can be regarded as heat engines and indeed their Carnot temperatures (those at
which heat carries the correct amount of work) can be determined. Distillation is a good example with heat
entering in the reboiler and exiting at the condenser. If heat is supplied at temperatures: (i) greater than the
Carnot temperature, the process will consume more work than it needs or (ii) less than the Carnot
temperature then the process is infeasible.
A diagram that shows regions of feasibility can be constructed using a chart of enthalpy versus the Gibbs
Free Energy of the process, the so-called G-H diagram. The chart also has an axis for Carnot temperature
which varies from minus infinity to infinity. The feasible zones are then found by choosing feasible Carnot
temperatures at which to run the individual pieces of equipment. For example steam provides constraints
because its useful temperature range is known (not necessarily its Carnot temperature), while the natural
process of photosynthesis, being driven by sunlight has a Carnot temperature about the same as that of the
sun.
The implications of the method are that a process can be examined in a logical and systematic way that
shows where the most energy-efficient and typically most economic process conditions exist. By using the
method, process designers will be stimulated to look at alternatives that better satisfy the feasible
constraints and answer the questions above by calculating achievable targets for processes.
Joint Chemical Engineering Committee
Technical Meeting
Design Processes for Least Energy Waste
Speaker
David Glasser is a Professor of Chemical Engineering and co-director of the Material and Process
Synthesis (MaPS) research unit at the University of South Africa (UNISA). He was a Professor of Chemical
Engineering, Head of Department of Chemical Engineering, and Dean of the Faculty of Engineering at
University of the Witwatersrand. He holds a B.S. in chemical engineering from University of Cape Town,
and a Ph.D. in chemical engineering from Imperial College and an Honorary DSc(Eng) from the University
of the Witwatersrand. His research interests have spanned nearly all aspects of chemical engineering,
including reaction engineering, process synthesis and design, heat and mass transfer, and
thermodynamics. He has had numerous awards and gold medals including the Billiton-NSTF Lifetime
Achievement Award.
For further information contact - Dr Jeffrey Shi
Phone: 0411449522 | Email: [email protected]
Event hosted by: Joint Chemical Engineering Committee