Toward a new integrated model for urban solid waste management: case study of Cajazeiras, Brazil

Abstract This study examines the implementation and effectiveness of the Public-Non-Governmental (PNG) integrated waste management model in the municipality of Cajazeiras, Paraíba, Brazil. The research addresses a gap in literature by exploring the PNG model, which combines governmental entities, non-governmental organizations (NGOs), and local waste picker cooperatives to enhance urban solid waste (USW) management. A case study was conducted at the Recyclable Materials Processing Unit (RMPU) in Cajazeiras, Paraíba, Brazil, over a four-month period. Data collection involved three on-site observation sessions (averaging six hours each), and documentary analysis of institutional records. Descriptive analysis was employed to examine the management structure, process mapping, and waste volumes. Key findings reveal that the PNG model facilitated the collection and treatment of 287. 503, 1 kg of waste in 2023, with paper (77. 16%), glass (9, 24%), and plastic (7, 44%) constituting most processed materials. The analysis of monthly targets and actual collections provided insights into operational efficiency, while process mapping identified the full waste flow from reception to final disposal. The results address the research question by highlighting key factors influencing the effectiveness of integrated public-private waste management in Brazilian municipalities, including governance structure, logistical organization, and the profile of materials processed. The model also formalized employment for waste pickers, improved living conditions, and fostered community engagement in sustainable practices. However, financial sustainability remains a challenge, with operational costs exceeding revenues in the initial years, the losses in that year were R524. 528, 82. The study highlights the critical role of municipal involvement in selective collection and public awareness campaigns to ensure long-term viability. The research concludes that the PNG model offers a viable alternative for municipalities with similar socio-economic conditions, promoting environmental sustainability and social inclusion. Recommendations include expanding infrastructure, increasing community participation, and strengthening intermunicipal partnerships to optimize waste management outcomes. The study contributes to understanding how inter-municipal associations and PNG models can impact sustainable waste disposal practices. How the PNG model should contribute to the discourse on innovative waste management models, emphasizing the importance of collaborative governance and adaptive strategies in developing regions.