In this study, co-digestion of mixed sewage sludge from a wastewater treatment plant (WWTP) and partially dephenolised two-phase olive pomace (DOP) as a co-substrate was addressed with the aim of improving the biodigestibility of both substrates. The introduction of DOP into WWTP anaerobic digester facilities could significantly increase biomethane production and enhance the sustainability of both activities. An improvement in the system’s performance was supported by stability parameters: total alkalinity increased and stabilised with the addition of 5% v/v DOP, and the specific energy loading rate was maintained at 0.177 ± 0.03 d−1, which indicated better buffer capacity and stability in the bioreactor, and the possibility of enhancing the organic loading rate. In terms of average daily biogas production rate, an increase of 39% was achieved, up to 0.39 ± 0.11 L L−1d−1. Moreover, there was a 40% and 37% improvement in specific methane production and methane production rate, respectively, up to 0.28 ± 0.02 L CH4 g TVS−1 and 0.26 ± 0.08 L L−1d−1. In addition, the proposed strategy leads to an energy saving of 20,328.6 kWh year−1 at the WWTP as a result of the electric energy production surplus, corresponding to an annual saving of €3293.23.

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The study reports the performance of a sanitary effluent treatment constituted by a septic tank, anaerobic filter and constructed wetland. The study monitored nutrient's, carbonaceous material's and thermotolerant coliform's (CT) removal efficiency during 12 months. The treatment system included a septic tank, an anaerobic filter and a horizontal subsurface flow constructed wetland cultivated with Typha spp. Effluent samples were monthly collected before and after the septic tank, anaerobic filter and wetland. The removal efficiency for N-NH + 4 was 37.6%, 66.3% for total P, 37% for COD, 54% for BOD and 99.4% for CT. The anaerobic filter and wetland were more efficient than the septic tank. P-total reduction was higher in the constructed wetland than in the anaerobic filter. Climatic conditions influenced the evaluated constituent's removal being the highest values during hot months. Desempenho do tratamento de esgoto com tanque séptico, filtro anaeróbico e wetland construído com Typha spp RESUMOO objetivo desta pesquisa foi avaliar o desempenho do tratamento do esgoto sanitário, no que se refere à remoção de nutrientes, material carbonáceo e coliformes termotolerantes, durante 12 meses de monitoramento. O sistema de tratamento era composto por um tanque séptico, filtro anaeróbio e wetland construído com escoamento horizontal subsuperficial cultivado com Typha spp. As amostras do efluente foram coletadas mensalmente antes e após passar pelo tanque séptico, filtro anaeróbio e wetland. A partir das análises realizadas, notouse que a eficiência do sistema na remoção para N-NH+4 foi de 37,6%; 66,3% para P-total; 37% para DQO; 54% para DBO e 99,4% para coliformes termotolerante. Em relação ao desempenho das fases, foi constatado que o filtro anaeróbio e o leito cultivado foram mais eficientes na Rev. Ambient. Água vol. 7 (supplement) -Taubaté 2019 2 Paulo Fortes Neto et al.redução do que o tanque séptico. A redução de P-total foi mais acentuada no wetland construído do que no filtro anaeróbio. A remoção dos constituintes investigados foi influenciada pela condição climática, sendo os maiores valores observados no período de verão e os menores no período de inverno.Palavras-chave: macrófitas, remoção de nutrientes, wetland construído.