Iranian Journal of

Backgrounds and Objectives: Landfill site selection is an important action in integrated solid waste management process. Difference criteria should be paid attention in site selection, so using of special methods are necessary to assimilate the criteria. In this research, GIS software and Analytical Hierarchy Process were used.
Materials and Methods: First of all, maps were built in considering to economical, social and environmental factors, in next step, each layer, was graded. Low grade showed non coordination or less coordination and high grade showed more coordination.
Results: Assimilate of graded map in AHP process, separates area into unsuitable, suitable and very
suitable parts.
Conclusion: Very suitable parts can have high priority in decision making and also suitable parts can have high priority for development projects in future.

Background and objectives: Nowadays, landfilling is most common method in many countries owing to lower cost and adaptation to wide range of solid waste. Site selection of landfill requires evaluating several parameters such as municipal government requirements, environmental regulations and a large number of quantitative and qualitative criteria. The aim of current study was to compare AHP and TOPSIS in landfill site selection. For this purpose, two mentioned methods were applied to select suitable site in Karaj. Materials and methods: In present study, 4 candidate sites in south of Karaj were selected for landfill by overlaying data layers (digital maps) and query functions in Arc GIS 9.2. Prioritizations between alternatives were conducted by AHP and TOPSIS technique according to the criteria mentioned. Eventually, we compared and evaluated the AHP results and TOPSIS results with each other. Result: According to AHP, site prioritization was 3,2,4,1 respectively whereas, in the case of TOPSIS, it was ranked 4,3,2,1, respectively. These results showed that both methods are suitable to determine site priority. Conclusion: As in AHP, alternatives are compared with respect to goal and criteria, consequently it has better precision and higher accuracy and confidence compared with TOPSIS.

Background and Objectives: Nemone Tehran Poultry Slaughterhouse having an area of 13000 m² is located at District 3, Region 5 of Tehran Municipality and in Morad Abad Quarter .This study aimed at analysis the environmental impacts of the abovementioned slaughterhouse. For this purpose, we applied analytical hierarchy process (AHP) as one of the multiple criteria decision making methods (MCDM). Materials and Method: First, we determined the criteria and options required through analyzing the project impacts. Then, for final validity of criteria, we used experts questionnaire. Special vector technique through using the Expert Choice software was used in order to set priorities for criteria and options. Results: Analysis of the slaughterhouse effluent indicated that it can neither be discharged into the surface water and well nor suitable for irrigation and agricultural purposes. Noise evaluation showed that rate of noise measured is beyond the standard limits. The laboratory experiment results on air pollutants was lower than the standard level. Conclusion: The results indicated that from the pollution perspective in the slaughterhouse, wastewater weighted 0.497 is the primary preference and sound, air, and odour weighted 0.229, 0.136 and 0.080 are the subsequent preferences. Cultural and socioeconomical environment ranked hgiher relative to the chemical-physical environment and then biological environment. Finally, regarding to the main significant environmental problem of slaughterhouse (Wastewater), optimization of the slaughterhouse wastewater treatment system and constant monitoring of the external sewage quality is in priority.

Background and Objectives: In this experimental study, we used Analytical Hierarchy Process method to determine the best wastewater treatment process for dairy products factories. That is a multi-criteria decision making techniques and is based on expert knowledge. Materials and Methods: First, we formed the hierarchical structure and defined the main criteria and indicators. Then, we investigated the current situation of the treatment process through field observations and conducting influent-effluent analysis. Later, we converted the results obtained into quantitative indices. Then we weighted the main criteria, and their related sub criteria, depending on existing conditions we performed the experiments required and considered the experts ideas. Finally, Evaluation and prioritization of the options was conducted using Expert choice software. Then the sensitivity analysis was performed for main criteria and we evaluated the influence of the parameters weight change on the options. Results: In comparison with the main criteria, environmental criteria were more important followed by engineering criteria, economic and management criteria. Conclusions: Due to the influence of various parameters in choosing optimal wastewater treatment, Multi-criteria decision-making methods are necessary. Finally, “UASB + Aeration” was found to be the first priority followed by “Anaerobic filter + Aeration”, “Anaerobic lagoon + Aeration (2) + Sedimentation (2)”,” Anaerobic filter + Aeration (2) + Sedimentation (2)”. “Septic tank + Trickling filter + Aeration” system was found to be less preferable than other options.