Impact Assessment of the Portuguese National Plan for Municipal Solid Waste 2014–2020

The assessment of the environmental, economic and employment impacts of packaging waste and MSW was commissioned by Sociedade Ponto Verde (SPV), the Portuguese Producer Responsibility Organization (PRO) for packaging waste, and resulted in two studies whose results are summarized here.

Environmental Impacts

The environmental assessment of the MSW management system in 2012 and 2020 was performed using attributional life cycle assessment (LCA). The functional unit selected as the basis for comparison was 1 ton of average MSW managed in Portugal in 2012. Coproducts were taken into account by the “substitution by system expansion” or “avoided burden method” considering the average primary route market consumption mix. The “zero burden assumption” was also used, which means that it was considered that the waste carries none of the upstream burdens into the waste management system (Clift et al. 2000).

For modeling purposes, the various activities were organized as groups of associated processes, as follows: (1) waste generation, (2) collection of sorted MSW (material and biodegradable waste); (3) collection of unsorted MSW; (4) organic recovery; (5) sorting at MRF; (6) mechanical treatment; (7) mechanical-biological treatment; (8) energy recovery; (9) recycling; (10) landfill. The secondary wastes from waste treatment, as also the materials and energy recovery processes, were also taken into account.

The detailed analysis of the most important foreground processes constitutes the backbone of the life cycle inventory and was based on primary data obtained from the companies that handle the waste (e.g. SPV) and on secondary data from LCA databases and scientific bibliography which were adapted to better reflect the Portuguese reality.

The results obtained show that for 7 of the 11 environmental impact categories considered in the study, the reference MSW system configuration leads to a positive or neutral environmental balance. In these cases, the benefits due to the recovery of materials and energy obtained by waste recovery processes (avoided impacts), with special focus on recycling, are bigger or at least equal to the negative impacts generated by the various waste management activities, like collection, sorting, transport, treatment and recovery. In the remaining four impact categories, the benefits obtained from waste recovery are not sufficient to mitigate the impacts generated by its management activities. This is due mainly to a still significant MSW fraction that is not recovered and is mostly eliminated in landfills (in 2012, 5 4 % of the Portuguese MSW was directly put in landfill). This is the case, for example, in the climate change category, where it was estimated that the net GHG emissions reached 1.1 Mt CO2eq in 2012, equivalent to 1.6 % of the annual GHG emissions in Portugal.

Comparing the MSW management as a whole with the specific management of packaging materials, it was found that, on a unit basis, the environmental balance of the packaging materials is more favorable than the remaining fractions. This is due in part to the intrinsic characteristics of packaging materials, but also to higher recycling rates achieved and the consequently lower amount sent to landfill, particularly for glass, paper/cardboard and ferrous metals.

Comparing the 2012 performance with the target for the year 2020 with the strategy defined in PERSU 2020, the results show that the proposed changes will lead to a major qualitative leap in the environmental performance of the sector. For example, it is estimated that the net GHG emissions will be reduced by 47 %, which translates into a emission savings of 522 kt CO2 eq and that the benefits obtained from the recovery of mineral resources, both fossil and renewable, will increase by 61 % compared to 2012. These benefits are due not only to reduction of the quantity sent to landfill, especially the biodegradable fractions, but also to the expected increase

Fig. 14.3 Environmental impacts of MSW management per ton of MSW in 2012 and 2020, according to the objectives of PERSU 2020. Three categories were omitted since in both cases the values were approximately null

in MSW recycling resulting from the increase of selective collection and more efficient treatment and recovery of mixed wastes (Fig. 14.3).

 
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