Evaluating the Efficiency of School Waste Collection Systems: A Qualitative and Quantitative Analysis

The quantitative and qualitative characterization of waste generated within educational institutions represents a fundamental step in evaluating the most suitable actions to optimize its management by the body in charge. In this context, a research activity was launched with the primary aim of describing waste production in the involved school complexes and estimating the relative waste sorting efficiencies. In particular, the study focused on waste production and collection across 14 classrooms in middle and high schools in the Southern Padua Province, all of which are served by the local waste management company S.E.S.A. SpA. The activities carried out made it possible to apply rigorous methodologies for conducting waste composition analysis campaigns, with specific reference to paper, plastic and metals, and residual waste fractions. The applied methodology allowed establishing a total school waste production equal to 10.81 g/person•day, a low value compared to literature data. This discrepancy could be explained by the collection procedures, which focused specifically on waste generated within classrooms, while overlooking waste produced in common areas used by students throughout the day. The detected fractions are plastic and metals (39%), paper (36%), organic waste (15%), and residual waste (10%). The trend monitored through the four sequential waste composition analysis campaigns confirms the stability of this compositional pattern. The monitoring of temporal progress highlighted, in particular, an increase in the efficiency of collection quality within the bins dedicated to plastic and metals (reaching a purity level of 80%) and to paper (reaching a purity level of 82%), supported by targeted educational and awareness-raising activities. This aspect is already a fundamental indicator for the progressive reduction of the residual waste share, which overall constitutes a small and unavoidable fraction of waste (1.06 g/person•day), however, from waste composition analysis, it appears contaminated by other potentially recyclable materials, such as organic waste, exhibiting a purity level of approximately 52%. Furthermore, the study evaluated how student age and different activities carried out by them could have an influence on their separation behaviors of discarded material. Indeed, the data show that: lower secondary schools record a total production of 10.32 g/person•day, in which paper represents the clearly dominant fraction with 47% of the total, and upper secondary schools present a slightly higher per capita production, equal to 11.30 g/person•day, with plastic becoming the main fraction, covering 45% of the overall waste. Regardless of the absolute values obtained, the results of the activity allowed to identify the methodological criticalities to be resolved for conducting future representative and rigorous plans of school waste characterization. In particular, the need has emerged to carry out the analysis no longer at the level of individual classes, but rather on the entirety of the waste collected in the entire school, in order to increase the representativeness of the collected data. In fact, although data show that waste streams are correctly separated by students in the classroom, with efficiencies in line with typical benchmark values, the main critical issues could emerge in the subsequent stages of the logistical and organizational management of the overall waste stream within the school premises.