MODELS AS METAPHORS - THE ROLE OF MODELING IN POLLUTION PREVENTION

Models can be considered as metaphors of some part of the physical world. The comparisons between implicit models and the systems they represent may not be explicitly expressed. Physical models represent reality by simulating some important physical characteristics of the real system. Mathematical models describe reality by mathematical relationships that can be as simple as an empirical equation or as complex as large sets of partial differential equations. All types of models contain assumptions and abstractions, and many contain computations. The broad definition applied to models leads to many applications in pollution prevention. They can be used to design new processes that produce products without the environmental problems of existing processes or they can be used to develop methods of operating existing processes that result in reduced pollution. They also can be used to evaluate environmental risks and to compare the environmental impacts of alternative products and processes. An example of applying models to environmental risks associated with converting to a recycled cooling water system is presented.