Optimal Planning for a Thermal Discharge Treatment System

Abstract

The characteristics and economic implications of thermal pollution are considered within the context of the planning of a treatment system for a series of hypothetical nuclear power plants that are to be located adjacent to a river. It is assumed that these power plants will discharge sufficient heated cooling water to make these treatment facilities necessary. The problem that is being considered is to determine the optimal planning of a treatment system. The objective of the planning procedure is to minimize the total annual cost for the construction and operation of the entire system. The constraint on this minimization process is not to violate a maximum temperature requirement within each reach or section of the river. The problem is solved by considering the effect that a bypass‐piping system has on temperatures within the river. The technique of bypass piping consists of piping waste water downstream to reaches of a river where the regenerative powers of the physical system have reduced the level of pollution to the extent that more waste water may be disposed. By noting that the bypass‐piping system allows the beginning and end temperatures of a section of the river to be controlled, a procedure can be developed for separating the optimization model of the entire system. This model is separated into a set of small subproblems that are solved by simulation and a system problem that is solved by dynamic programing. The results of the implementation of this model showed that the bypass‐piping system significantly reduced the cost of the entire treatment system.