Efficacy and reliability of upgraded industrial treatment plant at Porto Marghera, near Venice, Italy, in removing nutrients and dangerous micropollutants from petrochemical wastewaters

Chemical and petrochemical wastewaters contain a host of contaminants that require different treatment strategies. Regulation of macropollutants and micropollutants in the final discharge from industrial wastewater treatment plants (WWTPs) have become increasingly stringent in recent decades, requiring many WWTPs to be upgraded. This article presents an analysis of a WWTP treating petrochemicals in Porto Marghera, Italy, that recently was upgraded following legislative changes. Because of strict legal limits for macropollutants and micropollutants and a lack of space necessary for a full-scale WWTP overhaul, the existing activated sludge tank was converted into a membrane biological reactor. The paper presents experimental data collected during a five-month investigation showing the removal rates achieved by the upgraded plant for macropollutants (particularly nitrogen compounds) and micropollutants (heavy metals and organic and inorganic toxic compounds).     

Characterization of post-consumer polyolefin wastes by hyperspectral imaging for quality control in recycling processes

In this paper new analytical inspection strategies, based on hyperspectral imaging (HSI) in the VIS–NIR and NIR wavelength ranges (400–1000 and 1000–1700 nm, respectively), have been investigated and set up in order to define quality control logics that could be applied at industrial plant level for polyolefins recycling. The research was developed inside the European FP7 Project W2Plastics “Magnetic Sorting and Ultrasound Sensor Technologies for Production of High Purity Secondary Polyolefins from Waste”. The main aim of the project is the separation of pure polyethylene and polypropylene adopting an innovative process, the magnetic density separation (MDS). Spectra of plastic particles and contaminants resulting from post-consumer complex wastes and of virgin polyolefins have been acquired by HSI and by Raman spectroscopy. The classification results obtained applying principal component analysis (PCA) on HSI data have been compared with those obtained by Raman spectroscopy, in order to validate the proposed innovative methodology. Results showed that HSI sensing techniques allow to identify both polyolefins and contaminants. Results also demonstrated that HSI has a great potentiality as a tool for quality control of feed (identification of contaminants in the plastic waste) and of the two different pure polypropylene and polyethylene flow streams resulting from the MDS-based recycling process.     

Endocrine-disrupting chemicals in coastal lagoons of the Po River delta: sediment contamination,bioaccumulation and effects on Manila clams

The large estuary that the River Po forms at its confluence into the Adriatic Sea comprises a multitude of transitional environments, including coastal lagoons. This complex system receives the nutrients transported by the River Po but also its load of chemical contaminants, which may pose a substantial (eco)toxicological risk. Despite the high ecological and economic importance of these vulnerable environments, there is a substantial lack of information on this risk. In light of the recent amendments of the European Water Framework Directive (2013/39/EU), the present study investigated the sediment contamination of six coastal lagoons of the Po delta and its effects on Manila clams (Ruditapes philippinarum), exposed in situ for 3 months. Sediment contamination and clam bioaccumulation of a wide range of chemicals, i.e. trace metals (Cd, Cr, Ni, Hg, Pb, As), polybrominated diphenyl ethers (PBDEs), alkylphenols (APs), organochlorine compounds (PCBs, DDTs), polycyclic aromatic hydrocarbons (PAHs) and organotins (TPhT, TBT), suggested a southward increase related to the riverine transports. Where the River Po influence was more direct, the concentrations of contaminants were higher, with nonylphenol and BDE-209 exceeding sediment quality guidelines. Biometric indicators suggested the influence of contamination on organism health; an inverse relationship between PBDEs in sediments and clam condition index has been found, as well as different biota-sediment accumulation factors (BSAFs) in the lagoons.     

Peroxymonosulfate-Co(II) oxidation system for the removal of the non-ionic surfactant Brij 35 from aqueous solution

The non-ionic surfactant Brij 35 was effectively removed from concentrated aqueous solution by the peroxymonosulfate/Co(II) system, using oxone (2KHSO₅·KHSO₄·K₂SO₄) as a source of peroxymonosulfate. At pH = 2.3 and initial Brij 35 concentration in the range 680-2410 mg L⁻¹, 86-94% removal was achieved after 24 h, using Co(II) = 15 μM and oxone = 5.9 mM. The effectiveness of removal did not change when initial pH was in the range 2.3-8.2. After five subsequent additions of Co(II) and oxone to the solution, COD and TOC removals increased up to 64% and 33%, respectively. Radical quenching tests confirmed that sulfate radical was the dominant radical species in the system. The main identified by-products from surfactant degradation were: (a) low molecular weight organic acids; (b) aldehydes and formates with shorter ethoxy chain than Brij 35; (c) alcohol ethoxylates carrying hydroxyl groups bonded to ethoxy chain. By-products identification allowed to hypothesize the pathways of Brij 35 degradation.     

Simulating the production and dispersion of environmental pollutants in aerosol phase in an urban area of great historical and cultural value

Mathematical models were developed to simulate the production and dispersion of aerosol phase atmospheric pollutants which are the main cause of the deterioration of monuments of great historical and cultural value. This work focuses on Particulate Matter (PM) considered the primary cause of monument darkening. Road traffic is the greatest contributor to PM in urban areas. Specific emission and dispersion models were used to study typical urban configurations. The area selected for this study was the city of Florence, a suitable test bench considering the magnitude of architectural heritage together with the remarkable effect of the PM pollution from road traffic. The COPERT model, to calculate emissions, and the street canyon model coupled with the CALINE model, to simulate pollutant dispersion, were used. The PM concentrations estimated by the models were compared to actual PM concentration measurements, as well as related to the trend of some meteorological variables. The results obtained may be defined as very encouraging even the models correlated poorly: the estimated concentration trends as daily averages moderately reproduce the same trends of the measured values.     

Trace element biomonitoring using mosses in urban areas affected by mud volcanoes around Mt. Etna. The case of the Salinelle, Italy

Trace element impact was assessed using mosses in a densely inhabited area affected by mud volcanoes. Such volcanoes, locally called Salinelle, are phenomena that occur around Mt. Etna (Sicily, Italy) and are interpreted as the surface outflow of a hydrothermal system located below Mt. Etna, releasing sedimentary fluids (hydrocarbons and NaCl brines) along with magmatic gases (mainly CO(2) and He). To date, scarce data are available about the presence of trace elements, and no biomonitoring campaigns are reported about the cumulative effects of such emissions. In this study, concentrations of Al, As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, V, and Zn were detected in the moss Bryum argenteum, in soil and water. Results showed that the trace element contribution of the Salinelle to the general pollution was significant for Al, Mn, Ni, and Zn. The comparison of trace concentrations in mosses from Salinelle and Etna showed that the mud volcanoes release a greater amount of Al and Mn, whereas similar values of Ni were found. Natural emissions of trace elements could be hazardous in human settlements, in particular, the Salinelle seem to play an important role in environmental pollution.     

Application of Two Quality Indices as Monitoring and Management Tools of Rivers. Case Study: The Imera Meridionale River, Italy

On the basis of the European Water Framework Directive (2000/60), the water resources of the member states of the European Community should reach good quality standards by 2015. Although such regulations illustrate the basic points for a comprehensive and effective policy of water monitoring and management, no practical tools are provided to face and solve the issues concerning freshwater ecosystems such as rivers. The Italian government has developed a set of regulations as adoption of the European Directive but failed to indicate feasible procedures for river monitoring and management. On a local scale, Sicilian authorities have implemented monitoring networks of watersheds, aiming at describing the general conditions of rivers. However, such monitoring programs have provided a relatively fragmentary picture of the ecological conditions of the rivers. In this study, the integrated use of environmental quality indices is proposed as a methodology able to provide a practical approach to river monitoring and management. As a case study, the Imera Meridionale River, Sicily’s largest river, was chosen. The water quality index developed by the U.S. National Sanitation Foundation and the floristic quality index based on the Wilhelm method were applied. The former enabled us to describe the water quality according to a spatial–temporal gradient, whereas the latter focused on the ecological quality of riparian vegetation. This study proposes a holistic view of river ecosystems by considering biotic and abiotic factors in agreement with the current European regulations. How the combined use of such indices can guide sustainable management efforts is also discussed.