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In this study, the anammox process was applied for the first time to the treatment of ammonium-rich liquid residues produced by the two-stage anaerobic digestion of food waste (2sAD-FW); such residues may represent a significant environmental issue if not properly managed. A granular anammox reactor was fed with a progressively increasing share of partially nitritated 2sAD-FW wastewater. An alternative operating strategy based on partial by-pass of the partial nitritation unit was tested, in order to regulate the influent NO2/NH4 molar ratio without chemical addition. High nitrogen removal efficiency (89±1%) and negligible nitrite discharge rates were achieved, together with high nitrogen removal rate / nitrogen loading rate (NRR/NLR, 97±1%) and stable specific anammox activity (0.42±0.03 gN2-N/gVSS•d). The observed NH4removed/NO2-removed/NO3-produced molar ratio was in agreement with anammox stoichiometry, as confirmed by the low contribution (< 5%) of denitrification to nitrogen removal. Moreover, the possibility of using digital color characterization of granular biomass as a novel, simple tool for the monitoring of anammox biomass enrichment and process performance was investigated under dynamic conditions, using real wastewater: changes in granule color correlated well with the increasing share of 2sAD-FW wastewater in the influent (R 2 =83%), as well as with the decrease of anammox biomass abundance in the reactor (R 2 =68%). The results suggest that anammox may be successfully integrated into a 2sAD-FW system, thus enhancing its environmental sustainability.

Pollution by petroleum hydrocarbons is one of the major environmental problems in ports and it is mainly associated with ship/boat traffic and related facilities. Ports are not closed systems and their pollution may impact adjacent coastal areas. Hydrocarbon degraders and particularly the obligate hydrocarbonoclastic bacteria carry out a fundamental and global activity in biological removal of hydrocarbons in marine habitats.This study was carried out within MAPMED, a multidisciplinary project aimed to improve the environmental sustainability of tourist ports in the Mediterranean Sea with regard to monitoring and reduction of hydrocarbon pollution.Three tourist ports were selected as case study sites: Cagliari (Italy), El Kantaoui (Tunisia), and Heraklion (Greece). The degradation potential of the autochthonous bacterial communities was evaluated enumerating heterotrophs and hydrocarbon degraders by MPN in the surface seawater. Heterotrophs were significantly more abundant in seawater from Cagliari port as compared to El Kantaoui and Heraklion ports. On the contrary, higher viable titles of diesel-and phenanthrene-degraders were found in seawater from El Kantaoui port compared to the other two areas. Hydrocarbon-degrading bacteria were isolated and characterized regarding their phylogenetic position and catabolic abilities. The hydrocarbon degradation activities were evaluated by GC-MS in aerobic batch reactors on diesel as carbon source. The majority of degraders from Cagliari were assigned to Pseudomonas whereas strains from El Kantaoui and Heraklion were assigned to Alcanivorax and Marinobacter.The selection of the most appropriate methodologies for the eco-efficient remediation of petroleum-hydrocarbon contamination of selected sites is currently in progress. http://dx.

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