www.epa.gov/research
science in ACTION
INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE
Environmental Optimization Using the WAste Reduction Algorithm (WAR)
Introduction
Traditionally chemical process designs
were optimized using purely
economic measures such as rate of
return. The WAste Reduction
algorithm (WAR) was developed by
EPA scientists so that environmental
impacts of designs could easily be
evaluated. The goal of WAR is to
reduce environmental and related
human health impacts at the design
stage.
The WAR Algorithm
The WAR algorithm evaluates
processes in terms of potential
environmental impacts1"4. The
Potential Environmental Impact or
PEI of a chemical is defined as the
effect that a chemical would have on
the environment if it were simply
emitted into the environment.
Illustrated below, the WAR
algorithm assesses the
environmental friendliness of the
manufacturing portion of the product
life cycle. WAR characterizes the
PEI of the streams entering and
leaving the process boundaries.
The output rate of potential environmental impact for each category is shown in
the WAR screen shot below.
Energy
generation
process
Chemical Process
Results graph screen
Output rate of PEI*
4500
4000-
3500
£" 3000
A
Ml
£ 2500-
13 2000-
a
E 1500-
1000-
500-
'
GWP
Impact Categories
Unit 700 • Unit 701
* Impacts do HOT include the impact of product stream(s) and do include the impact of energy generation
** The total impact is calculated using impact weights so it may not equal the sum of the individual categories
WAR includes PEI from eight
categories:
• Human Toxicity Potential by
Ingestion
• Human Toxicity Potential by
Exposure
• Aquatic Toxicity Potential
• Terrestrial Toxicity Potential
• Global Warming Potential
• Ozone Depletion Potential
• Smog Formation Potential
• Acidification Potential
WAR GUI
To facilitate the use of the WAR
algorithm, EPA scientists
developed WAR GUI, the WAste
Reduction Algorithm Graphical User
Interface. WAR GUI is a freely
available program that allows users
to enter the necessary data for the
WAR algorithm:
• The flow rate and composition
of each stream entering and
leaving the chemical process
• The energy consumption rate
The process data can be entered
manually or imported from an
ASPEN Plus™ process simulator
output file. WAR GUI also allows
users to weight the different impact
categories based on preference.
U.S. Environmental Protection Agency
Office of Research and Development
EPA 600-F11027
August 2011
-------
WAR GUI Results
WAR GUI presents the results of the
WAR algorithm using a variety of
tables and graphs. For example the
user can compare the output rate of
potential environmental impact for
each category.
WAR Applications
The WAR algorithm has been used
to evaluate numerous processes in
order to determine the tradeoffs
between economic performance and
environmental impact. WAR has
been used to evaluate a fermentation
process for making penicillin3, the
production of benzene from toluene4
and recently ethanol generation from
corn and sugar cane5.
Below is a screen shot of the main
screen for the WAR GUI.
Collaboration
The WAR algorithm has been added
to AmsterCHEM's COFE (CAPE-
OPEN Flowsheeting Environment)6.
COFE is a freely available software
package for simulating chemical
processes7. COFE was built using
CAPE-OPEN standards which allow
software components from different
developers to be compatible8. It is
hoped that broad implementation of
CAPE-OPEN standards will enable
WAR to also be incorporated
directly into all commercial process
simulators.
References
1. Young, D.; Cabezas, H.
Computers and Chemical
Engineering, 23 (1999) 1477-
1491.
2. Young, D.; Sharp, R.; Cabezas, H.
Waste Management, 20 (2000)
605-615.
3. Hilary, A.; Sikdar, S. Industrial &
Engineering Chemistry Research,
34(1995)2051-2059.
4. Smith, R.; Mata, T.; Young, D.;
Cabezas, H.; Costa, C. Journal of
Cleaner Production, 12 (2004)
125-129.
5. Quintero, I; Montoya, M;
Sanchez, O.; Giraldo, O.;
Cardona, C. Energy, 33 (2008)
385-389.
6. Barrett, W; van Baten, J.; Martin,
T. Computers & Chemical
Engineering, in press (2011).
7. http://www.cocosimulator.org/
8. http://colan.org/
Mam screen
Step 1 Qedte new case hislwy tile or load S3wd case
hislwy tile
Step ? Add nflw case sniffy or import a case shiny from
ASPEN itpuil lite
Step :3 EditrVww case* information (Option)
Step.) FditMew Weighting Profits
Step 5: View Results
Stop 6' Create and view results file
5-EPA
New case history fil<
New Gase btudy
View/Edit Weights
Import cats.® study
IrumASPtN hie
View Hesults Graph
Create Resutts File
Vitrw itesulls Table
V«w Resets Tito
Vic-* Energy
Comparison Graph
Exit WAR
Contacts
Todd Martin, Ph.D., Office of Research
& Development, 513-569-7682,
martin.todd@epa.gov
Douglas Young, Ph.D., Office of
Research & Development, 513-569-
7624, young.douglas@epa.gov
U.S. Environmental Protection Agency
Office of Research and Development
EPA 600-F11027
August 2011
------- |