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Several pesticides and pharmaceuticals (PP) have been detected in the effluent of a full-scale Portuguese Wastewater Treatment Plant (WWTP). Their presence contributed to the environmental burdens associated with the existing treatment of the Municipal Wastewater (MWW) in the impact categories of Human Carcinogenicity, Non-Carcinogenicity, and Freshwater toxicities on average by 85%, 60%, and 90%, respectively (ReciPe2016 and USEtox methods). The environmental and economic assessment of the installation of an Anodic Oxidation (AO) unit for PPs’ removal was performed through Life Cycle and Economic Analysis, considering two types of anodes, the Boron-Doped Diamond (BDD) and the Mixed Metal Oxides (MMO). The operation of the AO unit increased the environmental burdens of the system by 95% on average (USEtox), but these impacts can be partially compensated by the avoided the production of non-renewable energy in the Portuguese electricity mix by biogas cogeneration at the WWTP. If the construction of the AO unit and the manufacturing of the electrodes are considered, the Human and Freshwater Toxicities are often higher than the environmental benefits derived from the PPs’ removal. On the economic side, the MMO configuration is clearly more advantageous, whereas BDD is environmentally more favorable. The issue of the presence of PP in MWW effluents has to be addressed as an integrated solution both improving upstream PP’s management and adopting PP’s removal technologies strongly supported by renewable energies. Further insights are needed for the assessment of fate and of the environmental effects of PP in the sludge.

A Life Cycle Analysis (LCA) based on ReCiPe 2016 model of a biorefinery case-study was performed. On the basis of an existing Portuguese Anaerobic Digestion plant, the proposed biorefinery hypothesized the use of (i) Maize Cob Waste (MCW) as co-substrate for Anaerobic co-Digestion (AcoD) with Organic Fraction Municipal Solid Waste (OFMSW), (ii) the use of MCW derived activated carbons (ACs) in a H2S removal unit, and (iii) the biogas upgrading to biomethane in a Pressure Swing Adsorption unit. The main aim was to compare the environmental benefits obtained from distinct uses of biogas, specifically the cogeneration of electricity/heat and biomethane production.Three biogas production configurations were considered: (i) AD of standalone hydrolysed OFMSW (hOFMSW); (ii) AcoD of hOFMSW and MCW pre-treated with H2O2 (hOFMSW+PreMCW); and (iii) AcoD of hOFMSW with non-pre-treated MCW (hOFMSW+MCW). The increase of biogas and methane yields obtained with AcoD of hOFMSW+MCW provided an overall better environmental performance than other configurations.The biogas upgrading to biomethane from AcoD of hOFMSW+MCW generated higher environmental impacts than cogeneration, due to the AC production and upgrading processes. If an optimised H2S adsorption capacity is considered, the Fossil Resource Scarcity, Mineral Resource Scarcity, and Global Warming human health impact categories decreased by 20%, 15%, and 17%, respectively, when compared to the base-case upgrading scenario. Further decreases of up to 52%, 23%, and 28% for those impact categories, respectively, are observed when the natural gas used in the OFMSW collection and transportation fleet is substituted by biomethane produced in the biorefinery.