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This work focuses on the application of the protocol for the assessment of the environmental footprint of products and organisations, performed accordingly with the prescriptions of the European Commission Recommendation 2013/179/EU. Although scientific and technical literature already reports some example cases carried out in several industrial fields, this methodology has not been run yet for the evaluation of the environmental performances of a wastewater treatment plant. The research has been carried out on a real scale plant, by acquiring, in parallel, operation data, chemical, physical and biological parameters throughout a 2-week campaign. Effluent toxicity towards the aquatic ecosystem was measured, by adopting a multi-tiered approach, the test organisms being crustaceans, bacteria and algae, respectively. The protocol for the evaluation of the environmental footprint was followed by considering as input data either the results of the chemical, physical and biological analyses or those deriving from the bioassays execution. The findings clearly illustrate the invaluable importance of bioassays in the process of evaluation of the environmental impact of any work, together with the need of combining different tests based on specific endpoints and involving organisms playing different trophic roles. [ABSTRACT FROM AUTHOR]

This work focuses on the Thermophilic Aerobic Membrane Reactor (TAMR) process. The research was carried out on a full-scale facility where, all along a 12-year period, daily monitoring and process audit tests were conducted for the process analysis and optimization. The plant treated -light and high-strength aqueous wastes and two different configurations were adopted: (1) thermophilic biological reactor + ultrafiltration (TAMR) and (2) TAMR + nanofiltration (TAMR + NF). In the latter case, the average chemical oxygen demand removal yield was equal to 89% and an effective denitrification (nitrogen oxides removal equal to 96%) was achieved by reducing the dissolved oxygen concentration in the bioreactor. Low specific sludge production was observed. Poor sludge settling properties were measured by a lab-scale settling test; respirometric tests (nitrogen uptake rate and ammonia uptake rate) showed the presence of denitrification and the inhibition of nitrification. Hydrodynamic tests revealed the presence of a significant dead space, thus showing room for improving the overall process performance. Finally, the rheological properties of the sludge were measured as a function of the biomass concentration, pH, temperature, and aeration scheme. [ABSTRACT FROM AUTHOR]

This research was carried out on a full-scale pure oxygen thermophilic plant, operated and monitored throughout a period of 11 years. The plant treats 60,000 t y-1 (year 2013) of high-strength industrial wastewaters deriving mainly from pharmaceuticals and detergents production and landfill leachate. Three different plant configurations were consecutively adopted: (1) biological reactor + final clarifier and sludge recirculation (2002-2005); (2) biological reactor + ultrafiltration: membrane biological reactor (MBR) (2006); and (3) MBR + nanofiltration (since 2007). Progressive plant upgrading yielded a performance improvement chemical oxygen demand (COD) removal efficiency was enhanced by 17% and 12% after the first and second plant modification, respectively. Moreover, COD abatement efficiency exhibited a greater stability, notwithstanding high variability of the influent load. In addition, the following relevant outcomes appeared from the plant monitoring (present configuration): up to 96% removal of nitrate and nitrite, due to denitrification; low-specific biomass production (0.092 kgVSS kgCODremoved-1 ), and biological treatability of residual COD under mesophilic conditions (BOD5/COD ratio = 0.25-0.50), thus showing the complementarity of the two biological processes. [ABSTRACT FROM AUTHOR]

Wastewater treatment plant (WWTP) effluents are considered to be a major source for the release in the aquatic environment of endocrine-disrupting compounds (EDCs). Ozone has proved to be a suitable solution for polishing secondary domestic effluents. In this work, the performance of a fullscale ozonation plant was investigated in order to assess the removal efficiency of four target EDCs: nonylphenol, nonylphenol monoethoxylate, nonylphenol diethoxylate and bisphenol A. The studied system was the tertiary treatment stage of a municipal WWTP which receives an important industrial (textile) load. Chemical analyses showed that the considered substances occurred with a significant variability, typical of real wastewaters; based on this, ozonation performance was carefully evaluated and it appeared to be negatively affected by flow-rate increase (during rainy days, with consequent contact time reduction). Moreover, EDCs' measured removal efficiency was lower than what could be predicted based on literature data, because of the relatively high residual content of biorefractory compounds still present after biological treatment. [ABSTRACT FROM AUTHOR]

In 2008, the G. Tovini Foundation (Brescia, Italy), together with the Universities of Brescia (Italy) and Dakar (Senegal), started a cooperation project (23PA07a) in the rural community of Patar (Senegal). The aim of the project was to improve the living conditions of the village people by controlling the quality of drinking water. Therefore, a 'multiple barrier approach', based on risk prevention, risk management, monitoring and compliance for insuring a safe drinking water supply, was applied including water treatment at household level and the assessment of the chemical-microbial risk. Water treatment was applied in order to reduce fluoride concentration in groundwater. Risk assessment was done throughout the chain from the catchment to the consumer so as to initiate appropriate remedial and preventive actions. Water was sampled from different points all along the supply system in order to verify the evolution of water quality and to identify the sources of pollution. Fluorides and microorganisms exceeded the World Health Organisation Guide Values, thus representing a serious health problem. In addition, while fluorides are naturally present in groundwater, microbiological contamination is mainly due to human habits (lack of hygiene) and therefore it increased during water transport and domestic storage. [ABSTRACT FROM AUTHOR]

Municipal sewage and WWTP effluents are considered to be a major source of pollution, regarding the occurrence of endocrine disrupting compounds (EDCs) in the environment. Although removal potential of many EDCs by conventional WWTPs is recognised, literature data are not easily comparable. Besides, in order to reach very low concentrations, a further treatment might be sometimes required. Positive results can be achieved by tertiary chemical oxidation; nevertheless, technical-economic suitability is still to be fully demonstrated. In this work, two estrogen-like susbstances were considered: nonylphenol (NP) (and its parent compounds) and bisphenol A (BPA). The experimental work was conducted at Verona (Northern Italy) WWTP (370,000 p.e.): after a 15 days sampling campaign, which was carried out in order to calculate mass balance of target compounds, chemical oxidation tests were performed on effluent by means of UV/H2O2 process and ozonation. Technical-economic feasibility of these solutions is discussed. [ABSTRACT FROM AUTHOR]

Full scale applications of activated sludge thermophilic aerobic process for treatment of liquid wastes are rare. This experimental work was carried out at a facility, where a thermophilic reactor (1,000 m³ volume) is operated. In order to improve the global performance of the plant, it was decided to upgrade it, by means of two membrane filtration units (ultrafiltration -UF-, in place of the final sedimentation, and nanofiltration -NF-). Subsequently, the integration with chemical oxidation (O3 and H2O2/UV processes) was taken into consideration. Studied solutions dealt with oxidation of both the NF effluents (permeate and concentrate). Based on experimental results and economic evaluation, an algorithm was proposed for defining limits of convenience of this process. [ABSTRACT FROM AUTHOR]

Alteration and decay of cultural heritage are caused by natural and anthropogenic factors, involving physical, chemical and biological phenomena. Deterioration processes often occur by means of phase transitions, most of which require months, years or also centuries to take place. This work is focused on phase transitions of marble monuments: main alteration processes of calcite are reviewed, including sulphation (and related crust formation), photochemical smog, oxalate patina and airborne sea-salts impact. Beside real case studies, experiments carried out at laboratory scale are proposed to predict material durability. Particular attention has been given to X-ray diffraction as one of the main characterization techniques, which represent a crucial step in cultural heritage conservation and restoration. [ABSTRACT FROM AUTHOR]

This research is aimed at assessing the particular kind of damage caused by the interaction between atmospheric pollution and the marble surface of a magnificent late gothic church, Milan Cathedral, restored in the early 1970s. On the basis of visual inspections and diagnostic investigations the facade appears to be seriously damaged by surface erosion and thick black crusts; biological crusts, micro-fractures and detachments are widely present. This paper reports on SR-μXRD data collected at the Synchrotron Radiation Source (SRS), Daresbury Laboratory, and at the European Synchrotron Radiation Source (ESRF) from selected samples, covered with black crusts, originating from the Milan Cathedral facade. Mineralogical maps of the deterioration layers have been recorded by two spatial resolutions (5–100 μm), from the bulk of the stone material to the outer layer of the black surface. These maps help in elucidating the mechanism of formation of the black crusts. [ABSTRACT FROM AUTHOR]

In this work, a real wastewater (deriving from the chemical-pharmaceutical field) was treated by means of H2O2/UV process under different conditions in a pilot-scale plant. Several methods were used in order to assess the oxidation efficiency and to understand the main reaction features. It was shown that nonconventional COD measurement (with a 75°C digestion of the sample) is helpful for understanding reaction mechanisms, when integrated with TOC and COD analyses and GC-MS determinations. For the biodegradability study, beside BOD (5 and 20 days) measurements, OUR and AUR tests provide additional information especially when wastewater is tested by taking the activated sludge from the treatment plant which should really be fed with it. Finally, dehydrogenase activity measurements can show the presence of complex organic matter, which may be degraded only by an acclimated biomass. [ABSTRACT FROM AUTHOR]

Compares different method for evaluating the biomass activity in activated sludge systems. Flow cytometric analysis; Heterotrophic bacteria plate count; Enzymatic activity determination; Oxygen Utilization Rate tests.

Describes some experiences concerning the application of chemical oxidation in the treatment of industrial wastewater in combination with other chemical-physical and/or biological processes. Wastewater from saturated and unsaturated polyester resin production; Assessment of optimal process conditions for the treatment of a wastewater from polystyrene production.