Selection of an Optimal Alternative for Wastewater Disposal in Combined Cycle Power Plants for Semi-arid Areas Using Analysis Hierarchical Process (AHP)

Living in arid and semi-arid regions is disrupted due to lack of water, and fossil fuel sources of combined cycle thermal power plants play an important role in generating electricity in these areas. The wastewater of these plants often contains various pollutants, including heavy metals, whose discharge to the environment can have a wide range of negative impacts. In this study, a model is presented to select the optimum disposal option of combined cycle power plants in semi-arid areas using the Analysis Hierarchical Process (AHP). The criteria and sub-criteria for determining optimal wastewater disposal in combined cycle power plants were selected based on consultation with experts in three main technical (۱۱ sub-criteria), economical (۴ sub-criteria), and environmental (۴ sub-criteria). The wastewater disposal option indicated that the environmental and technical criteria score for the evaporation pond is ۰.۰۶۹ and ۰.۱۲۶ and ۰.۲۲۸ and ۰.۲۰۵ for the zero liquid discharge, respectively. The results showed that environmental and then technical and economic criteria are the most important. Also, the most important environmental, technical, and economical sub-criteria are the safety of workers and people, system performance to achieve output standards, and operation and maintenance costs, respectively. To evaluate the model, the proposed method was applied to two combined cycle power plants in Yazd Province with an arid and semi-arid climate in central Iran. The results showed that regarding the characteristics of the power plants and the conditions of the area that is facing water shortage, the best option for disposal of wastewater in both plants is zero liquid discharge.

کلیدواژه ها:

Combined cycle power plant ، Hierarchical Analysis ، Semi-arid climate ، Wastewater disposal