نيلوفر ضيائي

Isfahan power plant is the oldest power plant in the Isfahan region. In recent years, the power plant has used the water of the Zayandehrud River for its internal use and cooling system, which has faced a shortage of water resources in recent years due to the decrease in rainfall and drought and as a result of reducing the volume of water from wells used. Therefore, it has treated the raw municipal wastewater to replace part of the water required for its domestic consumption for the first time in the Iran. In this treatment plant, in the first stage, like in other treatment plants, raw wastewater is converted into effluent, and in the second stage, to the extraction of industrial water, additional treatment steps are performed, during which suspended particles are separated and disinfected. The final result is quality industrial water production for the steam generation cycle. Due to the urgent need for water in the cooling system of the power plant and also the high costs of the wastewater treatment filtration system, the present study was conducted with the aim of the environmental-technical study of pig launcher operations for wastewater filtration and its use for the cooling system of Isfahan power plant. This research is done in two ways to extract reliable results. For this purpose, a pilot was designed to perform the filtration process by a pig, and input samples were taken before the sand filtration of the Isfahan power plant and placed in the pilot for the filtration process. The output results, were compared with the outputs of the sand filtration. In the next stage, key factors: initial investment, energy consumption, operation and maintenance costs, the ratio of treated water to water needed for washing, chemicals required initial, capital return time, environmental compatibility, useful life and BOD, COD, TDS, TSS, etc. removal efficiency identified. In the last step, the ANP-FUZZY was implemented for the technical-environmental assessment of key factors with the proposed options. The fuzzy-AHP was used to determine the weight of effective criteria in the eva‎luation. The results of the ANP model are presented in the form of unbalanced super matrix, weight super matrix, and limit super matrix tables. Then, the final weight of criteria and options were presented. Finally, the results of the ANP-FUZZY model showed that both sand filtration and pig filtration options are close to each other. According to the results of the pilot and ANP-FUZZY model, it can be concluded that pig filtration can be a suitable alternative to sand filtration or along with other filtration systems such as ultrafiltration and reverse osmosis as an efficient option as a hybrid system for filtration of the effluent treatment plant in Isfahan thermal power plant to be considered.

ارزيابي فني-زيست محيطي , فيلتراسيون , پيگ , مدل ANP-FUZZY

Technical-environmental assessment , filtration , pig , ANP-FUZZY model

Niloufar Ziaei

Dr. Alireza Zahedi