Assessment of Pollution Prevention Technologies
by Anthony Basco Halog
The understanding of environmental sustainability has been greatly enhanced by examining the Life Cycle Analysis and Assessment (LCA) of various products. The studies provided important answers to what materials and energies are used, how they are used and contribute to stability of the system. However, LCA techniques applied to products and processes implicitly assume that the systems concerned are functioning day to day at stable and operational levels. When these systems fail, the findings of current LCA studies are valueless because the assumed stability of the systems has been disrupted. Often, a failure can create an environmental impact significantly greater than could ever be imagined by investigators attempting to perform impact assessment based on normal operating conditions. One only has to remember the incidents of Bhopal, India, or Chernobyl, Ukraine, to understand the validity of this statement. The inability of current methodologies to account for the unstable variations greatly underestimates the impact of potential material and energy consumption as well as pollution generation. It is hypothesized that new methods are needed which build on current technologies to estimate these impacts. The overall objective of this research is to develop new methods by integrating LCA, Failure Modes and Effects Analysis (FMEA), and Petri Net modeling.
The approach taken in the project is to augment LCA with the knowledge that can be developed from FMEA and modeled using Petri nets. FMEA is a proven and well-used method for predicting complex system and component failures and their effects on system usability and safety. When combined with LCA, FMEA provides the ability to predict system failures and therefore potential requirement for increased material and energy as well as the potential for adverse environmental impacts including pollution generation increase. The use of Petri nets augments the ability to understand interaction between different failure modes and provides the ability to access the environmental impacts caused by combinations of the failure modes. The research in this project consists of three phases. The first phase will involve developing general algorithms and procedures that convert different types of FMEA representations into Petri net models. The second phase will be to develop general computational methods to effectively and efficiently quantify environmental impacts of failures, identify and evaluate pollution prevention solution alternatives. The final phase will involve testing and verifying the methods with industrial case studies and developing a computing system that implement the developed methodologies.
The failure of our system, in terms of the scientific and engineering definition of sustainability, are perturbations that may lead to instabilities achieving sustainability. The inability of current methodologies to account for the unstable variations in systems greatly underestimates the impact of potential material and energy consumption as well as pollution generation. The overall value of this research is to address this problem to sustainability and provide a feasible methodology that enables scientists to predict and perhaps prevent the instabilities which inhibit reaching sustainable development. By knowing what are the possible failures, the environmental stressors that the failures create, and what means exist to prevent the failures, we are more likely to reach the Brundtland Commission’s definition of sustainable development: “meet the needs of the present without compromising the ability of future generations to meet their own needs.”
Key Words: life cycle analysis, environmentally conscious manufacturing, failure modes and effects analysis, Petri net modeling