## 2 A Case Study for the MSW Management of the Procida Island
### Life Cycle Inventory
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{1}{c}{**Separately**} & \multicolumn{1}{c}{**Input**} & \multicolumn{1}{c}{**Sorting**} & \multicolumn{1}{c}{**Input**} & \multicolumn{1}{c}{**Remanufacturing**} & \multicolumn{1}{c}{**Substitutability**} \\ \multicolumn{1}{c}{**Collected Fraction**} & \multicolumn{1}{c}{**Composition to**} & \multicolumn{1}{c}{**Efficiency**} & \multicolumn{1}{c}{**Composition to**} & \multicolumn{1}{c}{**Efficiency**} & \multicolumn{1}{c}{**Substitutability**} \\ \hline
**Paper 3** & & & & & \\ \hline Paper and cardboard & 49\% & 95\% & - & - & - \\ packaging & 49\% & 95\% & - & - & - \\ \hline Other fractions & 51\% & - & - & - & - \\ \hline Paper to testliner & - & - & 56\% & 95\% & 0.9 \\ \hline Paper to newspapers & - & - & 44\% & 90\% & 0.94 \\ \hline
**Glass 4** & & & & & \\ \hline _Glass_ & 100\% & 90\% & 100\% & 100\% & 1 \\ \hline
**Metals 5** & & & & & \\ \hline _Fe_ & 82\% & 83\% & 83\% & 88\% & 1 \\ \hline _Non-Fe_ & 18\% & 94\% & 17\% & 94\% & 0.9 \\ \hline \hline \end{tabular}  
* \({}^{1}\) Corepla [16] and Conai [24] provided data for input compositions to sorting and remanufacturing phases, together with those related to sorting efficiencies; data from [21; 22] were used for remanufacturing efficiencies and substitutability factors, respectively. [2] They include PET, polylogfn, and stintens. It was assumed to be composed of 49% PET, 13% HDPE, 25% LDPE, 11% PP, and 2% PS. [3] Comico [17] provided data for input composition to sorting phases and sorting efficiencies; data from [22] were used for input composition to remanufacturing, remanufacturing efficiencies, and substitutability factors. [4] Coreve [18] provided data for input compositions to sorting and remanufacturing phases, together with those related to sorting and remanufacturing efficiencies; data from [22] were used for the substitutability factor. [5] Ricrea [19] and Cial [20] provided data for input compositions to sorting and remanufacturing phases, together with those related to sorting efficiencies; data from [22] were used for remanufacturing efficiencies and substitutability factors.  
\end{table} 
Table 1: _Cont._Organic fractions. The management of biowaste separately collected in Procida greatly improved over the last ten years, moving from exclusive utilisation of aerobic composting processes (in 2011) to the adoption of anaerobic digestion (AD) with production of energy or, in some cases, biomethane (in 2021). The aerobic process is carried out in bio-cells tunnels, with a residence time of 45 days, necessary to produce about 300 kg/t\({}_{\text{biowaste}}\) of compost used for landfill capping. The exhaust gases from bio-cells are treated in a biofilter to remove odorous substances and pollutants before their release into the atmosphere, while leachate generated is sent to an external treatment plant [8]. The anaerobic digestion process is implemented in a continuous-flow, stirred-tank reactor working under wet and mesophilic conditions (37-39 \({}^{\circ}\)C) and having a treatment capacity of 35,000 t\({}_{\text{biowaste}}\)/y. It produces about 140 m\({}^{3}\)N/t\({}_{\text{biowaste}}\) of biogas, containing 50.8%vol of CH\({}_{4}\), 44.6%vol of CO\({}_{2}\), and 4.6%vol of other compounds, which is sent to a combined heat and power (CHP) unit, having conversion efficiencies of 38% for electricity and 45% for thermal energy [25]. The environmental burdens deriving from biowaste management are shown in Table 3, quantified for both the process units starting from the same reference composition, as reported in ANNEX B.