Modeling the Causal Loop Diagram of the Waste Management Cycle and Providing a Solution to Organize the Existing Situation (Kerman Case Study)

Organizing the collection of valuable recyclable waste at the city level has always been a major challenge for municipalities due to unprincipled activities. So far, various attempts have been made to organize these people in Iran, but all of them have failed. Almost all municipalities have accepted the presence of these people as an informal part of urban waste management. The purpose of this study is to create a new financial structure in the form of an activity license and investigate the informal flow of waste collectors in three scenarios by the causal loop diagram of the waste management cycle in Vensim software. The causal loop model obtained in this research brings a new and complete understanding of stakeholders, effective variables in cooperation, and competition between formal and informal actors in the waste management cycle of Kerman City.

To simulate the performance of different financial license pricing scenarios, the concepts of simulation of system thinking, dynamic planning, and CLD model have been used in Vensim software. At first, the CLD model of the waste cycle in Kerman City was drawn and analyzed using local conditions, the infrastructures of Kerman Municipality, and the behavior of actors in collecting recyclable waste. The drawing model was developed in Vensim software based on the collected field data and statistics from 2021 to 2022. The new scenario was defined based on the use of financial licenses to organize the informal collectors of recycled waste and separation from the origin of the definition and the assumptions of the model. Three scenarios of the existing situation, the basic license price of 500000 and 1000000 Tomans were examined and compared with each other.

  According to the results, in scenario 2, the municipality's share of the recycling market has increased by about 204%, and the amount of the municipality's profit, including the amount of the license issuance along with the discount, has increased by 232%. In scenario 3, the municipality's share of the recycling market has increased by about 400% compared to the current situation, and compared to the second scenario, it has increased by 64%, and the amount of the municipality's profit has increased by 507% compared to the current situation.

Financial licenses in the field of municipal waste management have been used in their simplest form so far, which have been mostly ineffective. The use of smart financial and licensing systems based on field conditions, the dynamics of actors' behavior, and smart policies can be a suitable solution for organizing urban waste management, especially the informal waste collection fleet.