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Waste Reduction Algorithm: Chemical Process Simulation for Waste Reduction

Traditionally chemical process designs, focus on minimizing cost, while the environmental impact of a process is often overlooked. This may in many instances lead to the production of large quantities of waste materials. It is possible to reduce the generation of these wastes and their environmental impact by modifying the design of the process. The WAste Reduction (WAR) algorithm was developed 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 impacts (PEI). The potential environmental impacts of a chemical is defined as the effect that a chemical would have on the environment if it were simply emitted into the environment. The goal of this methodology is to minimize the PEI for a process instead of minimizing the amount of waste (pollutants) generated by a process.The impact estimation algorithm is sophisticated, yet flexible enough to allow users to emphasize or deemphasize different hazards as needed for particular applications.

WAR includes potential environmental impacts 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 algorithm has been integrated into the commercial simulator ChemCAD. 

Download WAR Software

WAR Installation (EXE)(29 MB)

Download Instructions

  1. Save the install.exe file to your hard drive. Due to the large size of the file, the download may take 15 minutes or lonter, depending on the speed of the connection.
  2. Once the file is saved on your hard drive, exit all open programs on your computer.
  3. Double-click on the install.exe file.
  4. In some cases, the computer may need to be rebooted in order to complete the installation process. Afterward, the WAR algorithm icon will appear on your desktop.
  5. Double-click the icon to start the program.


Environmental Optimization Using the WAste Reduction Algorithm (WAR) – August 2011

Fu, Y., U.M. Diwekar, D.M. Young and H. Cabezas. (2001). “Designing Processes for Environmental Problems.” Chapter 12 in Process Design Tools for the Environment, Edited by S.K. Sikdar and M. El-Halwagi. Taylor and Francis, New York, NY. p. 295–318.

Fu, Y., U.M. Diwekar, D.M. Young and H. Cabezas. (2000). “Process Design for the Environment: A Multi-Objective Framework Under Uncertainty.” Clean Products and Processes, 2, 2: 92–107.

Young, D.M. and H. Cabezas. (2000). “The Waste Reduction (WAR) Algorithm: Environmental Impacts, Energy Consumption, and Engineering Economics.” Waste Management, 20, 8: 605–615.

Young, D.M. and H. Cabezas. (1999). “Designing Sustainable Processes with Simulation: The Waste Reduction (WAR) Algorithm.” Computers & Chemical Engineering, 23, 10: 1477–1491.

Cabezas, H., J.C. Bare and S.K. Mallick. (1999). “Pollution Prevention with Chemical Process Simulators: The Generalized Waste Reduction (WAR) Algorithm - Full Version.” Computers & Chemical Engineering, 23, 4–5: 623–634.

Hilaly, A.K., S.K. Sikdar, H. Cabezas, S.K. Mallick and J. C. Bare. (1998). “Waste Reduction Using Computer-Aided Design Tools.” Encyclopedia of Chemical Processing and Design, Vol. 65, p. 97–119.

Cabezas, H., J.C. Bare and S.K. Mallick. (1997). “Pollution Prevention with Chemical Process Simulators: The Generalized Waste Reduction (WAR) Algorithm.” Computers & Chemical Engineering, 21, 1: S305–S310.

Mallick, S.K., H. Cabezas, J.C. Bare and S.K. Sikdar. (1996). “A Pollution Reduction Methodology for Chemical Process Simulators.” Industrial & Engineering Chemistry Research, 35, 11: 4128–4138.

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