urban waste

Rapid socio-economic development has significantly increased municipal solid waste (MSW) generation. Several urban waste management strategies have been analyzed to address environmental impacts and evaluate energy-based sustainability. This study evaluates emergy-derived Environmental Yield Ratio (EYR) and net emergy across different waste treatment methods.

A descriptive-analytical approach was applied. Emergy values for each input were calculated by converting physical quantities (mass, energy, monetary units) into standard emergy units using appropriate transformity factors. Stored emergy was also estimated. Emergy-based indicators were then derived to assess resource investment efficiency and potential for emergy recovery among waste management options.

Composting demonstrated Karaj's highest net emergy efficiency among the evaluated strategies. Emergy investment per gram of MSW was calculated as follows: sanitary landfill (6.51 × 10⁶ sej/g), incineration (4.61 × 10⁶ sej/g), and composting (8.06 × 10⁵ sej/g). EYR and net emergy values confirm composting as the most environmentally favorable alternative.

Emergy analysis indicates a direct relationship between higher EYR and increased net emergy. Composting outperforms sanitary landfilling in environmental performance, offering the most sustainable urban waste management solution for Karaj. Open Access Policy: This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/

Nowadays, the development of green entrepreneurship plays an important role in sustainable employment, reducing environmental issues, economic development, and moving towards sustainable development. Thus, the present study has been carried out aiming to identify and analyze the factors facilitating the green entrepreneurship process in the field of urban waste using a mixed (quantitative-qualitative) method.

The present study was carried out with a mixed approach (exploration projects). For this purpose, using theoretical sampling logic, 14 experts were selected by snowball technique and the required data were collected through semi-structured in-depth interviews to achieve theoretical saturation. In the quantitative section, data were collected through interaction questionnaires handed out to 26 experts who were selected through purposive sampling, and the integrated DEMATEL-ISM technique was employed to build a regular hierarchical structure.

Layer-by-layer model was displayed in 4 levels using DEMATEL-ISM technique. The first layer consists of improving laws and regulations and designing a suitable landscape as the most infrastructural, the second layer includes improving infrastructure issues, expanding supportive issues, culturalization and increasing public awareness, the third layer includes exploiting the potentials of the region and attracting private sector participation, and the fourth layer comprises of entrepreneurial management.

The results show that the first step in creating a facilitator environment for green entrepreneurship process in the field of urban waste is to improve the macro structures that should be facilitated mainly by the central government, the second step is related to the proper infrastructure and preparation of public space governing the society. In the third step, it was found that the development and utilization of the region’s potential increases its operational effectiveness. Finally, with entrepreneurial management, all activities that occurred at previous levels can be used effectively.

One of the most important environmental challenges of many developing countries is the disposal of urban waste as a sustainable solution. This study aimed to determine the most suitable location for the landfill in Hamidiyeh County using the hierarchical analysis model (AHP) and (GIS).

At first, 11 criteria were selected in three socioeconomic, hydrological, and geomorphological environments as effective criteria. Then the spatial data in the GIS software was transformed into new information layers. Each of the criteria and sub-criteria was weighted through the process of AHP according to the importance of them in locating the landfill.

The highest and the lowest weight belonged to socioeconomic criterion and the geomorphological criterion with a weight of 0.594 and 0.157, respectively. Finally, the appropriate location map was created for the landfill in four classes including completely appropriate, appropriate, inappropriate, and completely inappropriate. The results showed that 60% of the area was suitable for the landfill site. The site proposed for landfill based on the estimated land area for the next 20 years, was the C site located in the northwest with an area of 2505.788 hectares. In general, C site was more suitable than other sites, and there was little risk for pollution of surface water and environment. It also had the lowest cost of transporting and depositing waste to the landfill, in compliance with the environmental conditions.

The selected site should be considered by Hamidiyeh municipal waste management authorities to bury waste, concerning the unsuitable location of the current landfill site of the city.