Verifying the feasibility of wastewater-based epidemiological monitoring for the small catchment and sewage networks with significant pretreatment.

Wastewater-based epidemiology (WBE) has emerged as a valuable tool for COVID-19 monitoring, especially as the frequency of clinical testing diminishes. Beyond COronaVIrus Disease 19 (COVID-19), the tool's versatility extends to addressing various public health concerns, including antibiotic resistance and drug consumption. However, the complexity of sewage systems introduces noise when measuring chemical tracer concentrations, potentially compromising their applicability for modeling.

On the use of hydrodynamic modelling and random forest classifiers for the prediction of hypoxia in coastal lagoons.

Hypoxia is one of the fundamental threats to water quality globally, particularly for partially enclosed basins with limited water renewal, such as coastal lagoons. This work proposes the combined use of a machine learning technique, field observations, and data derived from a hydrodynamic and heat exchange numerical model to predict, and forecast up to 10 days in advance, the occurrence of hypoxia in a eutrophic coastal lagoon. The random forest machine learning algorithm is used, training and validating a set of models to classify dissolved oxygen levels in the lagoon.

Evaluation of different molecular systems for detection and quantification of SARS-CoV-2 RNA from wastewater samples.

Wastewater-based epidemiology has proved to be a suitable approach for tracking the spread of epidemic agents including SARS-CoV-2 RNA. Different protocols have been developed for quantitative detection of SARS-CoV-2 RNA from wastewater samples, but little is known on their performance. In this study we compared three protocols based on Reverse Transcription Real Time-PCR (RT-PCR) and one based on Droplet Digital PCR (ddPCR) for SARS-CoV-2 RNA detection from 35 wastewater samples.

Recovery of structural extracellular polymeric substances (sEPS) from aerobic granular sludge: Insights on biopolymers characterization and hydrogel properties for potential applications.

Nowadays, wastewater treatment plants (WWTPs) are transforming into water resource recovery facilities (WRRFs) where the resource recovery from waste streams is pivotal. Aerobic granular sludge (AGS) is a novel technology applied for wastewater treatment. Extracellular polymeric substances (EPS) secreted by microorganisms promote the aggregation of bacterial cells into AGS and the structural fraction of EPS (sEPS) is responsible for the mechanical properties of AGS.

Rigid and film bioplastics degradation under suboptimal composting conditions: A kinetic study.

The present research investigates the degradation rate of bioplastics under various composting conditions, including suboptimal ones. Lab-scale tests were carried out setting three variables: temperature (37°C-58°C), humidity (30%-60%) and duration of the thermophilic and the maturation phases (15-60 days). The composting tests were carried out following modified guideline ISO 20200:2015 and lasted for 60 days.

Heavy metal biosorption by Extracellular Polymeric Substances (EPS) recovered from anammox granular sludge.

The recovery and conversion of Extracellular Polymeric Substances (EPS) from sewage sludge into bio-based commodities might improve the economics and environmental sustainability of wastewater treatment. This contribution explores the application of EPS from anammox granular waste sludge as biosorbent for the removal of heavy metals, specifically lead, copper, nickel, and zinc. Adsorption capacities equivalent or higher than well-established adsorbent media emerged from single-metal biosorption studies (up to 84.

Aerobic Granular Sludge-Membrane BioReactor (AGS-MBR) as a Novel Configuration for Wastewater Treatment and Fouling Mitigation: A Mini-Review.

This mini-review reports the effect of aerobic granular sludge (AGS) on performance and membrane-fouling in combined aerobic granular sludge-membrane bioreactor (AGS-MBR) systems. Membrane-fouling represents a major drawback hampering the wider application of membrane bioreactor (MBR) technology. Fouling can be mitigated by applying aerobic granular sludge technology, a novel kind of biofilm technology characterized by high settleability, strong microbial structure, high resilience to toxic/recalcitrant compounds of industrial wastewater, and the possibility to simultaneously remove organic matter and nutrients.

A highly efficient multi-step methodology for the quantification of micro-(bio)plastics in sludge.

The present study develops a multi-step methodology for identification and quantification of microplastics and micro-bioplastics (together called in the current work micro-(bio)plastics) in sludge. In previous studies, different methods for the extraction of microplastics were devised for traditional plastics, while the current research tested the methodology on starch-based micro-bioplastics of 0.1-2 mm size.

Efficient carbon, nitrogen and phosphorus removal from low C/N real domestic wastewater with aerobic granular sludge.

This work reports on simultaneous nitrification, denitrification and phosphorus removal treating real domestic wastewater with low carbon/nitrogen (C/N) ratio by aerobic granular sludge (AGS). Operations at high sludge retention time (SRT = 61 ± 24 days) resulted in low biomass yield per chemical oxygen demand removed (COD) (0.21 ± 0.

Monitoring of degradation of starch-based biopolymer film under different composting conditions, using TGA, FTIR and SEM analysis.

This paper presents the results of a composting lab-scale test carried out on Mater-Bi® film, a starch-based biopolymer. The test material is composed by starch, additives and polybutylene adipate terephthalate (PBAT). The test lasted for 45 days and was developed in three replicates under different temperature and moisture conditions, with the aim to assess the influence on Mater-Bi® degradation of less favourable composting conditions as short thermophilic phase, absence of moistening, and a combination of the two factors.

Water safety plans and risk assessment: A novel procedure applied to treated water turbidity and gastrointestinal diseases.

Water Safety Plans (WSPs), as recommended by the World Health Organization (WHO), can help drinking water suppliers to identify potential hazards related to drinking water and enable improvements in public health outcomes. In this study we propose a procedure to evaluate the health risk related to turbidity in finished water by determining the cases of drinking water-related gastrointestinal diseases. The results of several epidemiological studies and three-year time series turbidity data, coming from three different drinking water treatment plants (WTPs) located in Tuscany (Italy), have been used to determine the relationship between drinking water turbidity and gastroenteritis incidence and to assess the health risk attributable to the turbidity of tap water.

Hydrogels formed by anammox extracellular polymeric substances: structural and mechanical insights.

The recovery of biopolymers from the waste sludge produced in wastewater treatments and their application in other industrial sectors, would substantially increase the environmental and economical sustainability of the process, promoting the development of a circular economy. In this study, extracellular polymeric substances (EPS) extracted from anammox granular waste sludge, were investigated and characterized. Rheological and differential scanning calorimetry measurements on EPS aqueous dispersions indicate the formation of an extended 3-D network above a threshold concentration, with a clear dependence of the mechanical and water retention properties on EPS content.

Methodologies to assess biodegradation of bioplastics during aerobic composting and anaerobic digestion: A review.

Bioplastics are emerging on the market as sustainable materials which rise to the challenge to improve the lifecycle of plastics from the perspective of the circular economy. The article aims at providing a critical insight of research studies carried out in the last 20 years on the degradation of bioplastics under aerobic composting and anaerobic digestion conditions. It mainly focuses on the various and different methodologies which have been proposed and developed to monitor the process of biodegradation of several bioplastic materials: CO and CH measurements, mass loss and disintegration degree, spectroscopy, visual analysis and scanning electron microscopy.

Extraction, recovery and characterization of structural extracellular polymeric substances from anammox granular sludge.

The composition and colloidal properties of extracellular polymeric substances (EPS) from anammox granular sludge were investigated through a complete set of spectroscopic and scattering techniques. To fully characterize EPS, we developed a robust and reproducible extraction/recovery protocol specific for anammox biofilms, based on the change of water affinity under alternated alkaline and acidic conditions, each monitored with Z-potential and dynamic light scattering analysis. This method enabled both extraction as a colloidal suspension and recovery as a solid of large amounts of EPS (0.

Nitrifying biomass characterization and monitoring during bioaugmentation in a membrane bioreactor.

A membrane bioreactor (MBR), fed with domestic wastewater, was bioaugmented with nitrifying biomass selected in a side-stream MBR fed with a synthetic high nitrogen-loaded influent. Microbial communities evolution was monitored and comparatively analysed through an extensive bio-molecular investigation (16S rRNA gene library construction and terminal-restriction fragment length polymorphism techniques) followed by statistical analyses. As expected, a highly specialized nitrifying biomass was selected in the side-stream reactor fed with high-strength ammonia synthetic wastewater.

European trends in greenhouse gases emissions from integrated solid waste management.

The European Union (EU) has 28 member states, each with very different characteristics (e.g. surface, population density, per capita gross domestic product, per capita municipal solid waste (MSW) production, MSW composition, MSW management options).

Modeling bioaugmentation with nitrifiers in membrane bioreactors.

Bioaugmentation with nitrifiers was studied using two pilot-scale membrane bioreactors, with the purpose of assessing the suitability of state-of-the-art activated sludge models (ASMs) in predicting the efficiency of bioaugmentation as a function of operating conditions. It was demonstrated that the temperature difference between seeding and seeded reactors (ΔT) affects bioaugmentation efficiency. Experimental data were accurately predicted when ΔT was within a range of up to 10 °C at the higher range, and when the temperature was significantly lower in the seeded reactor compared to the seeding one, standard ASMs overestimated the efficiency of bioaugmentation.

Biodegradation of naphthalenesulphonate polymers: the potential of a combined application of fungi and bacteria.

The potential of several fungi and their synergy with bacterial biomasses were evaluated as a solution for the removal of 2-naphthalensulphonic acid polymers (2-NSAPs) from petrochemical wastewater, characterized by a chemical oxygen demand (COD) greater than 9000 mg/L. The ability of fungi to grow on 2-NSAP mixtures was preliminarily investigated using a solid medium, and then the action of the selected strains, both in suspended and immobilized form, was evaluated in terms of degradation, depolymerization, sorption and an increase in biodegradability of 2-NSAP. Among the 25 fungi evaluated two, in particular, Bjerkandera adusta and Pleurotus ostreatus, have been found to significantly depolymerize 2-NSAP yielding to the corresponding monomer (2-naphthalenesulphonic acid, 2-NSA), which has been further degraded by a bacterial consortia selected in a wastewater treatment plant (WWTP).

Monitoring the oxygen transfer efficiency of full-scale aeration systems: investigation method and experimental results.

This paper reports the results of a series of off-gas tests aimed at monitoring the evolution of the oxygen transfer efficiency in an urban wastewater treatment plant (3,500 population equivalent) located in Tuscany (Italy). The tests were conducted over a 2-year period starting with the testing of the aeration system. It was found that in the absence of membrane-panel cleaning operations, the oxygen transfer efficiency under standard conditions in process water (αSOTE) dropped from 18 to 9.

Characterization and comparison of bacterial communities selected in conventional activated sludge and membrane bioreactor pilot plants: a focus on Nitrospira and Planctomycetes bacterial phyla.

A pilot-scale membrane bioreactor (MBR) and a conventional activated sludge system (CAS) were in parallel operated to investigate the impact of the separation technology on the structure and functionality of the selected microbial community. Microbial communities as well as nitrogen removal efficiency of the biomass were characterized. Kinetics and microbial community structure turned out to be duly correlated.

Techno-economic evaluation of the application of ozone-oxidation in a full-scale aerobic digestion plant.

This paper deals with the application of the ozone-oxidation in a full scale aerobic sludge digester. Ozonation was applied continuously to a fraction of the biological sludge extracted from the digestion unit; the ozonated sludge was then recirculated to the same digester. Three different ozone flow rates were tested (60,500 and 670g O3 h(-1)) and their effects evaluated in terms of variation of the total and soluble fractions of COD, nitrogen and phosphorous, of total and volatile suspended solids concentrations and Sludge Volume Index in the aerobic digestion unit.

Biomass accumulation modelling in a highly loaded biotrickling filter for hydrogen sulphide removal.

A pilot scale test on a biotrickling filter packed with polyurethane foam cubes was carried out for 110 d at high volumetric mass load (up to 280 g m(bed)(-3) h(-1)) with the aim of studying the accumulation of solids in the treatment of H(2)S. Removal rate up to 245 g m(bed)(-3) h(-1) was obtained; however, an accumulation of gypsum, elemental sulphur and, above all, inert biomass was identified as the cause of an increased pressure drop over the long term. A mathematical model was applied and calibrated with the experimental results to describe the accumulation of biomass.

Factors affecting the growth rates of ammonium and nitrite oxidizing bacteria.

The maximum specific growth rates of both ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) were investigated under varying aerobic solids retention time (SRT(a)) and in the presence/absence of anoxic (alternating) conditions. Two bench SBRs, reactor R1 and R2, were run in parallel for 150d. Reactor R1 was operated in aerobic conditions while R2 operated in alternating anoxic/aerobic conditions.