Ammonium recovery from municipal wastewater by ion exchange: Development and application of a procedure for sorbent selection

Ion exchange represents one of the most promising processes for ammonium recovery from municipal wastewater (MWW). However, most previous studies on ammonium ion exchange did not optimize the process or evaluate its robustness under real operational conditions. This experimental study aimed at (i) developing a procedure for the selection of a sorbent for selective ammonium removal/recovery from MWW, (ii) validating the procedure by applying it to several sorbents, (iii) performing a preliminary optimization and robustness assessment of ammonium removal/recovery with the selected sorbent. The application of the procedure to natural and synthetic zeolites and a cation exchange resin confirmed that batch isotherm tests need to be integrated by continuous-flow tests. The selected sorbent, a natural mixture of Chabazite and Phillipsite, resulted in high performances in terms of cation exchange capacity (33 mgN gdry resin-1), ammonium operating capacity (5.2 mgN gdry resin-1), ammonium recovery yield (78-91%) and selectivity towards ammonium. The process performances resulted stable during 7 adsorption/desorption cycles conducted with MWW treatment plant effluents in a 60-cm column. The switch to a highly saline effluent produced in a hotspot of seawater intrusion did not determine significant changes in performances. Contact time was reduced to 6 min without any decrease in performances. Potassium – well tolerated by crops – was selected as the regenerating agent, in the perspective to produce a desorbed product to be re-used as fertilizer. The study shows that Chabazite/Phillipsite has a high capacity to recover ammonium from MWW in a circular economy approach

Examining the Relationship of Clinical and Laboratory Parameters With Infectiousness to Phlebotomus perniciosus and Its Potential Infectivity in Dogs With Overt Clinical Leishmaniasis

Infected dogs are considered the main domestic animal reservoirs for Leishmania infantum parasite. Infectiousness to competent phlebotomine vectors has been associated with many factors, the main being the severity of the disease exhibited by infected dogs. This study examines the relationship between different clinical parameters and the infectiousness to colonized Phlebotomus perniciosus sand flies having a blood meal on dogs. Data obtained in the present study come from an untreated group of Leishmania sick dogs submitted to xenodiagnosis for the evaluation of a spot on insecticide solution. Seventeen dogs were diagnosed as affected by leishmaniasis through clinical examination, immunofluorescence antibody test (IFAT) serology, and loop-mediated isothermal amplification (LAMP). The disease severity (clinical score) was staged by using a numeric value derived from eight clinical and parasitological parameters. Xenodiagnosis was performed on caged dogs exposed for 1.5 h to sand-fly bites. The following parameters related to sand flies were examined: blood feeding (% of blood engorged females), promastigote detection (% of promastigote-positive sand flies), promastigote burden, and the promastigote stage maturation (potential transmissibility rate). Statistical relationship between the clinical score and entomological parameters was investigated, as well as the possible correlation between each clinical and laboratory parameters and sand fly infection/infectivity. The severity of clinical score may influence the blood feeding by, and the probability of promastigote detection in, sand flies; skin lesions seem to be the main factor that influences the rate of blood feeding. Promastigote burden is related to IFAT titer, skin lesions, and clinical score. All entomological parameters are strongly related among them. This study confirms that both P. perniciosus infection and infectivity are influenced by a dog’s clinical condition

Timing methodologies and studies at the FERMI free-electron laser.

Time-resolved investigations have begun a new era of chemistry and physics, enabling the monitoring in real time of the dynamics of chemical reactions and matter. Induced transient optical absorption is a basic ultrafast electronic effect, originated by a partial depletion of the valence band, that can be triggered by exposing insulators and semiconductors to sub-picosecond extreme-ultraviolet pulses. Besides its scientific and fundamental implications, this process is very important as it is routinely applied in free-electron laser (FEL) facilities to achieve the temporal superposition between FEL and optical laser pulses with tens of femtoseconds accuracy. Here, a set of methodologies developed at the FERMI facility based on ultrafast effects in condensed materials and employed to effectively determine the FEL/laser cross correlation are presented

Closing the plastic waste material cycle in the power industry

Cables and wires are widely used in electronic equipment and power industry for transmission of both data and electricity, where the rapid development of power lines and constant update of electronic devices have resulted in an increase of waste cables. However, recycling of cables and wires is mainly focused on the recovery of metallic fraction due to their higher market value, rather than other plastics used in insulation. Polymeric materials from the scrap cables are often disposed in landfills or incinerated, which results significant risks to health and the environment due to the release of hazardous substances. Among different recycling techniques, the pyrolysis process is a promising alternative for waste recycling, where plastics are trasformed into light gases and oils which can be useful raw materials for fuels and/or chemical/polymer production. This study aimed to analyze the problems related to cable waste recycling in detail, especially to the chemical recycling of the main polymers, which is an alternative route to incineration and landfill. An extensive literature search has therefore been carried out on the pyrolysis of the main polymeric materials used in cables, such as polyethylene, cross-linked polyethylene, and polyvinyl chloride. Finally, a method was proposed to analyse different polymers from cables in a pyrolysis reactor on a laboratory scale

From anaerobic membrane bioreactors to water resource recovery facility: experimental validation and sustainability assessment

La transizione dal concetto di ‘’impianto di trattamento delle acque reflue’’ a quello di ‘’impianto di recupero di risorse dalle acque reflue a bassa impronta di carbonio’’ è stata indirizzata affrontando i seguenti temi: il riutilizzo dell'acqua depurata, il recupero di risorse e la valutazione dell'impronta di carbonio. In particolare, per quanto riguarda il riutilizzo dell'acqua depurata sono stati analizzati e confrontati trattamenti convenzionali di affinamento del refluo e soluzioni innovative che prevedono trattamenti anaerobici a membrana. In questo contesto, è stata operata per circa due anni una filiera di trattamento a scala pilota, composta da un reattore anaerobico UASB combinato con una membrana di ultrafiltrazione (AnMBR). Operando con un carico organico (OLR) di 1 kg COD/m3/giorno, la produzione di biogas era di circa 0.39 ± 0.2 L/giorno. L'aumento dell'OLR a 2 kg COD/m3/giorno ha determinato un aumento della produzione di biogas fino a 4.11 ± 3.1 L/giorno. Le condizioni di elevata salinità (1500 mgCl/L) hanno influito negativamente sulla produzione di biogas senza creare fenomeni di sporcamento aggiuntivi alla membrana. L'effluente finale trattato soddisfa gli standard di qualità della CLASSE A del nuovo regolamento UE 741/2020 per il riutilizzo dell'acqua ed è adatto per scopi di fertirrigazione in agricoltura. Un'unità aggiuntiva è stata combinata al trattamento AnMBR per la rimozione dei contaminanti emergenti (CECs), utilizzando polimeri a impronta molecolare (MIPs). È stata avviata una colonna di adsorbimento e il diclofenac è stato utilizzato come composto target. L'efficienza di rimozione è risultata pari al 50%. Sono state inoltre indagate la presenza di microplastiche (MPs) nelle acque reflue. Dai risultati sperimentali lo schema a fanghi attivi convenzionali, in scala reale, ha rimosso l'86% di MPs, mentre la filiera anaerobica su scala pilota ha ottenuto una rimozione del 94%. In questo scenario è stato anche progettato e realizzato un prototipo per il campionamento di volumi di refluo significativi al fine di rilevare concentrazioni rappresentative di MPs. Sono stati affrontati, inoltre, l’aspetto dell’inquinamento dovuto ai sovraflussi di piena della fognatura mista e i problemi relativi alla balneazione delle acque validando in campo filiere di trattamento modulari composte da filtro rotativo dinamico, adsorbimento su carbone attivo granulare e disinfezione UV. I risultati del pilota hanno mostrato rimozioni di TSS, COD ed E.Coli rispettivamente pari al 90%, 69% e 99%. Inoltre, sono stati condotti studi di fattibilità su impianti in piena scala che prevedono l’integrazione di soluzioni di recupero delle risorse quali fosforo, acidi grassi volatili e biopolimeri. In particolare, sono state valutate, utilizzando metodi quali CBA, S-LCA ed SRL, soluzioni eco-innovative, sviluppate nell'ambito del progetto H2020 Smart-Plant da integrare agli impianti esistenti ai fini di chiudere il ciclo dell’acqua. Complessivamente, gli impianti di depurazione integrati con le SMARTechs mostrano benefici ambientali e sociali, con un valore economico totale (TEV) massimo superiore di un 23% rispetto allo scenario di base, mentre i valori di SRL sono risultati nel range 6-7, dimostrando una buona accettazione sociale e un buon potenziale di adattamento delle SMARTechs. Infine, è stato approfondito il tema del Carbon Footprint per il servizio di depurazione, proponendo un nuovo approccio metodologico. La maggior parte dei fattori di emissione considerati è stata validata da campagne di misura in 12 impianti. I valori specifici dell’impronta di carbonio sono pari a 0.04-0.20 tonCO2eq/AE/anno, variabili in base alle dimensioni dell'impianto. Le categorie più impattanti sono state individuate nelle emissioni indirette associate ai GHG disciolti, scaricati nel corpo idrico superficiale e al consumo energetico, che contribuiscono rispettivamente per il 13-70% e il 10-40%.Technical solutions for the transition from ‘wastewater treatment plant’ (WWTP) to the concept of ‘low-carbon water resource recovery facility’ (WRRF) were assessed, addressing i) water reuse, ii) resource recovery and iii) carbon footprint assessment. Specifically, in terms of water reuse, conventional ‘’fit-for-purpose’’ treatments and innovative solutions as anaerobic treatments were analysed and compared. A pilot scale system, placed in a hotspot of seawater intrusion, composed of an upflow granular anaerobic sludge blanket (UASB) reactor coupled with AnMBR (Anaerobic Membrane Bioreactor) was set-up and operated for more than 2 years. At an organic loading rate (OLR) of 1 kg COD/m3/d, biogas production was around 0.39 ± 0.2 L/d. The increase of the OLR to 2 kg COD/m3/d resulted in increase of biogas production to 4.11 ± 3.1 L/d with fermented cellulosic sludge addition. High saline conditions of 1500 mgCl/L adversely affected the biogas production without deteriorating the membrane operation. The final effluent met quality standards of CLASS A of the new EU regulation741/2020 for water reuse and resulted suitable for fertigation purposes in agriculture. An additional unit was coupled with the AnMBR treatment for removing contaminants of emerging concern (CECs), using Molecurarly Imprinted Polymers (MIPs) as adsorbent filler. An adsorption column was started-up and diclofenac was used as target compound. Removal efficiency was up to 50%. Additionally, microplastics (MPs) occurrence and removals in wastewater treatments were investigated. The full-scale conventional activated sludge scheme removed 86% of MPs, while the pilot-scale UASB+AnMBR configuration achieved 94% MPs removal. The results highlighted an accumulation phenomenon of MPs in the sludge and this affected negatively the methanogenic activity of anaerobic biomass. In this scenario also a prototype system for collecting significant wastewater sampling volumes to detect more representative MPs concentrations was designed and realized. On the other hand, water pollution in stormwater and related water bathing issues were addressed assessing combined sewer overflows (CSOs) management strategies and validating advanced compact treatments, composed of dynamic rotating belt filter, adsorption on granular activated carbon and UV disinfection, to minimize their impacts. The results of pilot treatment showed great potential for TSS, COD and E. coli removal efficiencies with more than 90%, 69% and 99%, respectively. Moreover, feasibility studies in full-scale WWTPs, addressing resource recovery solutions, including phosphorous salts, volatile fatty acids and biopolymers recovery were carried out. In particular, real environment eco-innovative solutions, developed within the H2020 Smart-Plant project to renovate existing WWTPs and close the circular value chain, were assessed using Cost-Benefit Analysis (CBA), Social Life Cycle Assessment (S-LCA) and Social Readiness Level (SRL) methods. Overall, the SMARTechs created benefits both from an environmental and social point of view, with a maximum total economic value (TEV) up to +23% compared to baseline scenario. In terms of social assessment SMARTechs fell in SRL range of 6-7, which implies a good societal acceptance and adaptation potential. Finally, Carbon Footprint Assessment for the wastewater treatment service was deeply investigated, proposing a new methodological evidence-based approach. Most of the considered emissions factors for carbon footprint assessment were validated by site-specific measurements campaigns in 12 WWTPs. Specific carbon footprints resulted in the emissions of 0.04-0.20 tonCO2eq/PE/y, varying according to the size of the plant. The most impactful categories were identified for indirect emissions associated with dissolved GHGs discharged in the surface water body and due to energy consumption, which accounted for 13–70% and 10–40%, respectively

Targeted Bio-Based Volatile Fatty Acid Production from Waste Streams through Anaerobic Fermentation: Link between Process Parameters and Operating Scale

Anaerobic processes are proven to have much more environmental and economic benefits than conventional aerobic treatment systems, offering sustainable energy and valuable biochemicals. In recent years, bio-based volatile fatty acid (VFA) production has come into prominence as more value is derived before ending up with other final products. This paper presents a critical review of the research studies on bio-based VFA production from different waste streams (i.e., industrial sludge/waste, organic fraction of municipal solid waste/food waste, municipal wastewater/sludge, combined streams) through anaerobic fermentation. Fundamentals and decisive process parameters (i.e., pH, temperature, retention time, organic loading rate) are reviewed, and their correlations with VFA yields are critically discussed based on 178 cases (156 lab- and 22 pilot-scale). The picture we provided clearly demonstrates that process parameters should be clearly defined and optimized according to the type of waste streams which may have a significant impact on downstream processes in most cases

Demo-scale up-flow anaerobic sludge blanket reactor coupled with hybrid constructed wetlands for energy-carbon efficient agricultural wastewater reuse in decentralized scenarios

The impact of climate change on water availability and quality has affected agricultural irrigation. The use of treated wastewater can alleviate water in agriculture. Nevertheless, it is imperative to ensure proper treatment of wastewater before reuse, in compliance with current regulations of this practice. In decentralized agricultural scenarios, the lack of adequate treatment facilities poses a challenge in providing treated wastewater for irrigation. Hence, there is a critical need to develop and implement innovative, feasible, and sustainable treatment solutions to secure the use of this alternative water source. This study proposes the integration of intensive treatment solutions and natural treatment systems, specifically, the combination of up-flow anaerobic sludge blanket reactor (UASB), anaerobic membrane bioreactor (AnMBR), constructed wetlands (CWs), and ultraviolet (UV) disinfection. For this purpose, a novel demo-scale plant was designed, constructed and implemented to test wastewater treatment and evaluate the capability of the proposed system to provide an effluent with a quality in compliance with the current European wastewater reuse regulatory framework. In addition, carbon-sequestration and energy analyses were conducted to assess the sustainability of the proposed treatment approach. This research confirmed that UASB rector can be employed for biogas production (2.5 L h-1) and energy recovery from organic matter degradation, but its effluent requires further treatment steps to be reused in agricultural irrigation. The AnMBR effluent complied with class A standards for E. coli, boasting a concentration of 0 CFU 100 mL-1, and nearly negligible TSS levels. However, further reduction of BOD5 (35 mg L-1) is required to reach water quality class A. CWs efficiently produced effluent with BOD5 below 10 mg L-1 and TSS close to 0 mg L-1, making it suitable for water reuse and meeting class A standards. Furthermore, CWs demonstrated significantly higher energy efficiency compared to intensive treatment systems. Nonetheless, the inclusion of a UV disinfection unit after CWs was required to attain water class B standards

Targeted Bio-Based Volatile Fatty Acid Production from Waste Streams through Anaerobic Fermentation: Link between Process Parameters and Operating Scale

Anaerobic processes are proven to have much more environmental and economic benefits than conventional aerobic treatment systems, offering sustainable energy and valuable biochemicals. In recent years, bio-based volatile fatty acid (VFA) production has come into prominence as more value is derived before ending up with other final products. This paper presents a critical review of the research studies on bio-based VFA production from different waste streams (i.e., industrial sludge/waste, organic fraction of municipal solid waste/food waste, municipal wastewater/sludge, combined streams) through anaerobic fermentation. Fundamentals and decisive process parameters (i.e., pH, temperature, retention time, organic loading rate) are reviewed, and their correlations with VFA yields are critically discussed based on 178 cases (156 lab- and 22 pilot-scale). The picture we provided clearly demonstrates that process parameters should be clearly defined and optimized according to the type of waste streams which may have a significant impact on downstream processes in most cases

Anaerobic Membrane Bioreactor for Urban Wastewater Valorisation: Operative Strategies and Fertigation Reuse

In European scenario, the potential source for water supply from treated wastewater is actually estimated in 1,100 Mm3/y (EU-ENV, 2015). Anaerobic processes compared with conventional aerobic ones, cause a net reduction of the operative costs and possible reuse for fertigation purposes. The tested anaerobic pilot (HRT 6 h and T 30\ub0C) is constituted from a UASB reactor (16 L). Increment of influent organic loading rate (OLR) was studied for 1 year from 1 to 2 kgCOD/m3/d by feeding raw wastewater (Period 1), methanol (Period 2) and fermented supernatant from cellulosic sludge (Period 3).The biogas production was assessed equal to 0.13 m3biogas/kgCOD (Period 1), to 0.57 m3biogas/kgCOD (Period 2) and to 0.24 m3biogas/kgCOD (Period 3) with methane percentages constant around 33%. UASB effluent has not the final quality to comply limit values for water reuse and fertigation, especially for microbiological parameters. Further treatments could be necessary to achieve the removals of bacteria, such as E.Coli, recalcitrant organic traces and metals. Therefore, some advanced post treatments have been studied in this paper after UASB treatments, like UV disinfection, UV coupled with H2O2 and GAC adsorption. The innovative solution is coupling UASB reactor with anaerobic submerged sidestream AnMBR (UF hollow fiber membrane with 0.03 \u3bcm of nominal pore-size and 0.5 m2 of surface area KOCH, Puron single bundle). Membrane cleaning was carried out using sodium hypochlorite solution (400 ppm) each 45 days to remove organic fouling and to recover the initial permeability of the membrane. The average operative flux at process temperature was equal to 8.8\ub11.9 L/h/m2 and operating TMP of 44.6\ub18.5 mbar was detected. The removal of E.Coli was investigated in the effluent from UASB and in the permeate from AnMBR process. At clean membrane conditions, complete removal of bacteria (99\ub11%) was found. Furthermore, the determination of microplastics distribution was carried out both in the experimental anaerobic pilot and in the conventional full scale aerobic treatment plant. The effluent microplastics were quantified and the removal role of the different operative units was studied