Purpose: Prioritization of investment projects is a key step in the process of planning the investment activities of organizations. Choosing the suitable projects has a direct impact on the profitability and other strategic goals of organizations. Factors affecting the prioritization of investment projects are complex and the use of traditional methods alone cannot be useful, so there is a need to use a suitable model for prioritizing projects and investment plans. The purpose of this study is to prioritize projects and investment methods for projects (10 projects) considered by the Waste Management Organization of Tabriz Municipality. Methodology: The method of analysis used is the theory of rough, so that first the important investment projects in the field of waste management were determined using the research background and opinion of experts and the weight and priority of the projects were obtained using the Rough Sets Theory. Then, the priority of appropriate investment methods (out of 6 methods) of each project was obtained using Rough numbers, the opinion of experts and other aspects. Findings: The result of the research has been that construction project of a specialized recycling town, plastic recycling project, and recycled tire recycling project are three priority projects of Tabriz Municipality Waste Management Organization, respectively. Three investment methods, civil partnership agreements, BOT, and BOO can be used for them. Originality/Value: Tabriz Municipality Waste Management is an important and influential organization in the activities of the city, in which the investment methods in its projects are mostly based on common contracts and are performed in the same way for all projects. This research offers new methods for projects and their diversity according to Rough Sets technique.

Clustering of investment projects is an essential step in the process of planning the investment projects of organizations. Choosing the right project portfolio has a direct impact on the profitability and other strategic goals of organizations. Factors affecting the clustering of investment projects are many and the use of traditional methods alone cannot be useful, so it is necessary to use a suitable model for clustering projects and investment plans. The purpose of this research is to analysis investment projects of the Tabriz Municipality Waste Management Organization. Methodology: This research is a descriptive -survey method in terms of its objectives. The method used is Fuzzy clustering (FCM), in which the first large investment projects in waste management using the background of participants in research and investment clusters(3 clusters) using the FCM clustering approach is determined, then the priority of the appropriate investment methods (from 6 methods) of each project was obtained using expert judgment and other aspects. Due to the need for planning and clustering of investment projects, using the opinion of experts (10 experts), the importance of projects with ecological perspective was examined. Findings: The result of the research has been that Recycled tire recycling, Glass recycling, Electronic waste recycling, Plastic recycling and Construction project of a specialized recycling town are important projects that located in the first cluster and under normal circumstances, three investment methods, civil partnership agreements, BOT, and partnership contracts (property from the municipality) can be used for them. Originality/Value: Tabriz Municipality Waste Management is an important and influential organization in the activities of the city, in which the investment methods in its projects are mostly based on common contracts and are performed in the same way for all projects. This research offers new methods for projects and their diversity according to clustering technique.