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1.
J Environ Manage ; 261: 110144, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148255

RESUMEN

Successful water recycling initiatives depend on public acceptance. In this study, we compared risk percpetions of water labeled as recycled or reclaimed.We recruited 1264 subjects in an online panel (Qualtrics) and randomly assigned them either treatment (recycled or reclaimed) water and asked about the contents and perceived risk. Participants in the reclaimed condition were more likely to perceive the water to have harmful ingredients compared to the recycled condition. The odds of direct use acceptance for those in the recycled condition are 1.41 times (or 41%) more likely than those in the reclaimed condition. Similar results were found for indirect uses. A major finding of this study is that terminology influences the perceived contaminants and risk of reused water. Prior studies have found strong evidence that the way reused water is communicated can influence public perception. Policy impilcations favor the use of recycled water, likely due to the positive connotation recycling has in the U.S. today..


Asunto(s)
Opinión Pública , Riesgo , Purificación del Agua , Agua , Humanos , Reciclaje , Aguas Residuales , Abastecimiento de Agua
2.
J Environ Manage ; 261: 109879, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148248

RESUMEN

Heavy metal pollution, because of its high toxicity, non-biodegradability and biological enrichment, has been identified as a global aquatic ecosystems threat in recent decades. Due to the high efficiency, low cost, satisfactory recyclability, easy storage and separation, biosorbents have exhibited a promising prospect for heavy metals treatment in aqueous phase. This article comprehensively summarized different types of biosorbents derived from available low-cost raw materials such as agricultural and forestry wastes. The raw materials obtained are treated with conventional pretreatment or novel methods, which can greatly enhance the adsorption performance of the biosorbents. The suitable immobilization methods can not only further enhance the adsorption performance of the biosorbents, but also facilitate the process of separating the biosorbents from the wastewater. In addition, once biosorbents are put into large-scale use, the final disposal problems cannot be avoided. Therefore, it is necessary to review the currently accepted final disposal methods of biosorbents. Moreover, through the analysis of the adsorption and desorption mechanisms of biosorbents, it is not only beneficial to find the better methods to improve the adsorption performance of the biosorbents, but also better to explain the influencing factors of adsorption effect for biosorbents. Especially, different from many researches focused on biosorbents, this work highlighted the combination of biosorbents with catalytic technologies, which provided new ideas for the follow-up research direction of biosorbents. Finally, the purpose of this paper is to inject new impetus into the future development of biosorbents.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Ecosistema , Aguas Residuales
3.
J Environ Manage ; 261: 109911, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148250

RESUMEN

The leaking of harmful organic liquids into water resources has had hazardous impacts on living organisms. Herein, we demonstrated the fabrication of hybrid sorbents using s-PPG and organosilane cross-linker. The final product exhibited high, quick absorption capacity, great reusability and excellent oil separation performance from wastewater. They also selectively absorb different oils from the bottom and surface of water without any capacity change, even in harsh conditions like wavy and sub-zero water environment. Experimental results demonstrated that the obtained sorbents are efficient to successfully remove oil from water surface, even at harsh conditions, and float on the water surface before and after oil sorption without any capacity loss and structural change. Simple preparation by avoiding time consuming multistep process, initiator, solvent, activator free reaction medium, high and selective sorption characteristics and great reusability could make these sorbents a promising candidate for the cleaning of water from harmful organic liquids, by absorbing them.


Asunto(s)
Contaminación por Petróleo , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Aceites , Aguas Residuales
4.
J Environ Manage ; 261: 110173, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148263

RESUMEN

Green walls that effectively treat greywater have the potential to become a part of the solution for the issues of water scarcity and pollution control in our cities. To develop reliable and efficient designs of such systems, the following two research questions were addressed: what would be the optimal design of a green wall for greywater treatment, and how tall should the system be to assure adequate treatment. This paper reports on (i) a long-term pollutant removal comparison study of two typical green wall configurations: pot and block designs, and (ii) a short-term profile study exploring pollutant retention at different heights of a three-level green wall, across different plant species. Removal of suspended solids (TSS), nitrogen (TN), phosphorus (TP), chemical oxygen demand (COD) and Escherichia coli was tested, as well as various physical parameters. Pot and block designs were found to exhibit similar pollutant removal performance for standard and high inflow concentrations, while the block design was more resistant to drying. However, due to its multiple practical advantages, pot designs are favoured. The greatest removal was achieved within the top green wall level for all studied pollutants, while subsequent levels facilitated further removal of TSS, COD, and TN. Interestingly, colour, pH, and EC increased after each green wall level, which must be taken into account to determine the maximum height of these systems. The optimal size of the system was found to be dependent on plant species choice. The results were used to create practical recommendations for the effective design of greywater treatment green walls.


Asunto(s)
Fósforo , Contaminantes Químicos del Agua , Análisis de la Demanda Biológica de Oxígeno , Ciudades , Color , Nitrógeno , Aguas Residuales
5.
J Environ Manage ; 261: 110189, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148265

RESUMEN

The removal of styrene from wastewater by pervaporation was investigated by using composite PDMS membranes filled with reduced graphene oxide on PES support layers. Graphene oxide was synthesized through modified Hummers' method and then chemically reduced. The filler was characterized by TEM, SEM, XRD, and AFM. The top layers with different PDMS molecular weights were cast on the PES supports, which were prepared by phase inversion method. The characterizations of prepared membranes were investigated by SEM, AFM, contact angle measurement, TGA, and DSC. It was observed that presence of the filler in the polymeric matrix controls the swelling of the membrane and enhances its solubility parameter in favor of styrene. Moreover, it significantly improves the thermal stability of the membranes. The mechanism of separation in the process was found to be affected mainly by enhancing in the membrane's solubility rather than in its diffusivity. The pervaporative performance of prepared membranes showed their great affinity toward styrene so that the separation factor of the optimum membrane (M2/S) was increased about 250% (600.4 in comparison to 241.4 for the unfilled membrane) while its total flux was decreased from 772.5 g m-2.h-1for the unfilled membrane to 321.9 g m-2.h-1. Increasing the molecular weight of PDMS lowered the optimal rGO content due to the complexity of the diffusion path and occupation of free volume by longer polymer chains. Accordingly, a lower total flux (124.7 g m-2.h-1 for high MW compared to 718.0 g m-2.h-1 for low MW) and higher separation factor (822.5 for high MW compared to 230.8 for low MW) were yielded for the same filler content (0.1 wt% rGO).


Asunto(s)
Grafito , Aguas Residuales , Membranas Artificiales , Estireno
6.
J Environ Manage ; 261: 110198, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148271

RESUMEN

Globally, buildings are recognized as one of the highest users of freshwater resources. Consuming enormous amounts of constructional and operational water deplete water resources and ultimately generates a high environmental impact. This is mainly due to the energy required for the water cycle of built environments, which involves raw water treatment and distribution, use within buildings, and wastewater treatment. Moreover, the impact of water use varies significantly among countries/regions, due to different water use cycles. For example, many countries use conventional water treatments, while others rely on advanced desalination. Unlike building energy use, the impact of water use in buildings has not been captured fully in research. Given the significant impact of water use in buildings and global environmental degradation, we aimed to review studies concentrating on constructional and operational water use and associated environmental impacts, as well as studies that employed life cycle assessment (LCA) on this topic. The review indicated that a limited number of studies have focused on this serious issue in recent years, and their aims differed greatly. Therefore, there is a notable research gap in comprehensive environmental impact assessment including the total human water use cycle. Complete environmental assessment through LCA enables building professionals to understand the wide-ranging impact of water use in a building's life cycle from the environmental perspective in a given region. Additionally, this approach can benefit policymakers setting guidelines for new sustainable water strategies aimed at reducing environmental impacts.


Asunto(s)
Purificación del Agua , Agua , Ambiente , Agua Dulce , Humanos , Aguas Residuales
7.
J Environ Manage ; 261: 110208, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148278

RESUMEN

Based on the panel data of 18 prefecture-level and above cities in the Yangtze River Delta region of China during the period of 2007-2016, this paper uses a relative price approach to calculate the degree of market integration (segmentation), and further adopts the dynamic spatial panel Durbin model and the generalized spatial two-stage least squares method to investigate the effect and its mechanism of market integration on environmental pollution. The results show that the degree of market integration and the total emissions, per capita emissions, and emission intensity of three types of pollutants (i.e., sulfur dioxide, industrial wastewater, and industrial smoke and dust) all show an inverted "U-shaped" curve relationship. When market integration exceeds a certain critical level, market integration will have an emission-reduction effect on these three types of pollutants. Most cities in the Yangtze River Delta region are in an emission-reduction state of market integration. Market integration facilitates strengthening the emission-reduction effects of technological innovation, environmental regulation, and energy efficiency. Moreover, both environmental pollution and market integration have a significant spatial spillover effect. The market integration in neighboring regions is conducive to reducing local pollution emissions. We suggest that China should accelerate market-oriented reform and promote regional market integration, so as to make full use of the emission-reduction effect of market integration.


Asunto(s)
Industrias , Ríos , China , Ciudades , Monitoreo del Ambiente , Aguas Residuales
8.
J Environ Manage ; 261: 110219, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148289

RESUMEN

Emission of N2O represents an increasing concern in wastewater treatment, in particular for its large contribution to the plant's carbon footprint (CFP). In view of the potential introduction of more stringent regulations regarding wastewater treatment plants' CFP, there is a growing need for advanced monitoring with online implementation of mitigation strategies for N2O emissions. Mechanistic kinetic modelling in full-scale applications, are often represented by a very detailed representation of the biological mechanisms resulting in an elevated uncertainty on the many parameters used while limited by a poor representation of hydrodynamics. This is particularly true for current N2O kinetic models. In this paper, a possible full-scale implementation of a data mining approach linking plant-specific dynamics to N2O production is proposed. A data mining approach was tested on full-scale data along with different clustering techniques to identify process criticalities. The algorithm was designed to provide an applicable solution for full-scale plants' control logics aimed at online N2O emission mitigation. Results show the ability of the algorithm to isolate specific N2O emission pathways, and highlight possible solutions towards emission control.


Asunto(s)
Óxido Nitroso , Eliminación de Residuos Líquidos , Huella de Carbono , Análisis por Conglomerados , Aguas Residuales
9.
J Environ Manage ; 261: 110220, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148290

RESUMEN

Faecal pollution modelling is a valuable tool to evaluate and improve water management strategies, especially in a context of water scarcity. The reduction dynamics of five faecal indicator organisms (E. coli, spores of sulphite-reducing clostridia, somatic coliphages, GA17 bacteriophages and a human-specific Bifidobacterium molecular marker) were assessed in an intermittent Mediterranean stream affected by a wastewater treatment plant (WWTP). Using Bayesian inverse modelling, the decay rates of each indicator were correlated with two environmental drivers (temperature and streamflow downstream of the WWTP) and the generated model was used to evaluate the self-depuration distance (SDD) of the stream. A consistent increase of 1-2 log10 in the concentration of all indicators was detected after the discharge of the WWTP effluent. The decay rates showed seasonal variation, reaching a maximum in the dry season, when SDDs were also shorter and the stream had a higher capacity to self-depurate. High seasonality was observed for all faecal indicators except for the spores of sulphite-reducing clostridia. The maximum SDD ranged from 3 km for the spores of sulphite-reducing clostridia during the dry season and 15 km for the human-specific Bifidobacterium molecular marker during the wet season. The SDD provides a single standardized metric that integrates and compares different contamination indicators. It could be extended to other Mediterranean drainage basins and has the potential to integrate changes in land use and catchment water balance, a feature that will be especially useful in the transient climate conditions expected in the coming years.


Asunto(s)
Aguas Residuales , Calidad del Agua , Teorema de Bayes , Monitoreo del Ambiente , Escherichia coli , Heces , Humanos , Estaciones del Año , Microbiología del Agua
10.
J Environ Manage ; 261: 110224, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148294

RESUMEN

This work presents the degradation of ampicillin (a highly consumed ß-lactam antibiotic) in aqueous media by sonochemical advanced oxidation processes. Initially, effects of frequency, power and operation mode (continuous vs. pulsed) on the antibiotic degradation by sonochemistry were analyzed. Then, under the suitable operational conditions, pollutant degradation and antimicrobial activity (AA) evolution were monitored. Afterwards, computational calculations were done to establish the possible attacks by the hydroxyl radical to the ampicillin structure. Additionally, the antibiotic degradation in synthetic hydrolyzed urine by ultrasound was performed. Finally, the combination of sonochemistry with Fenton (sono-Fenton) and photo-Fenton (sono-photo-Fenton) was evaluated. Our research showed that ampicillin removal was favored at low frequency, high power (i.e., 375 kHz, 24.4 W) and continuous mode (exhibiting an initial degradation rate of 0.78 µM min-1). Interestingly, ampicillin degradation in the hydrolyzed urine by sonochemistry alone was favored by matrix components (i.e., the pollutant showed a degradation rate in urine higher than in distilled water). The sonochemical process decreased the antimicrobial activity from the treated water (100% removal after 75 min of treatment), which was related to attacks of hydroxyl radical on active nucleus (the computational analysis showed high electron density on sulfur, oxygen and carbon atoms belonging to the penicillin core). Sono-photo-Fenton system achieved the fastest degradation and highest mineralization of the pollutant (40% of organic carbon removal at 180 min of treatment). All these aspects reveal the good possibility of sonochemical advanced oxidation technologies application for the treatment of antibiotics even in complex aqueous matrices such as hydrolyzed urine.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Ampicilina , Peróxido de Hidrógeno , Oxidación-Reducción
11.
J Environ Manage ; 261: 110229, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148299

RESUMEN

Technologies for water recycling within oil refineries have been gaining interest at an extensive rate due to the large volume of wastewater generated, high dependency of water and the progressive scarcity of this valuable resource. Phenols are part of a specific class of organic pollutants that have been contributing to a low-quality effluent in oil refineries due to their hazardous nature and strict environmental legislation associated. The reuse of stripped sour water within refineries is often blocked due to its rich phenolic content. This study evaluates the retention of phenols in refinery wastewater through reverse osmosis (RO) at its major source of emission, for water reclamation. The RO membrane selected exhibited rejections of up to 98% of phenols and 99% of both chemical oxygen demand (COD) and total organic carbon (TOC). Permeate quality remained intact despite flux decline caused by phenolic and hydrocarbon adsorption when the oil content, in the feed, reached 771 ppm. The effluent's low conductivity due to lack of salts led to minor osmotic pressure differences (less than 2.5 bar at a volume concentration factor of 3), therefore, showing appealing performances of reverse osmosis filtration. Characterization of all permeates obtained from cross-flow filtration experiments showed COD levels in line with water reuse quality standards for make-up water in cooling processes.


Asunto(s)
Eliminación de Residuos Líquidos , Purificación del Agua , Filtración , Hidrocarburos , Membranas Artificiales , Ósmosis , Presión Osmótica , Fenoles , Aguas Residuales
12.
J Environ Manage ; 261: 110236, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148306

RESUMEN

The fast growth in the anthropogenic activities, that involve a wide use of pharmaceuticals, has led to the appearance of new toxic and hazardous chemical compounds, called "emerging pollutants", which could cause unpredictable consequences to the ecosystems. The current review is focused on emerging pollutants occurring in food or air and include caffeine and nicotine, as well as on pharmaceuticals, in particular amoxicillin, and the concerns caused by its wide usage for medical purposes. This review, for the first time, analyzes and discusses the potential risks and implications of caffeine, nicotine and amoxicillin as emerging environmental pollutants, a field that remains underrepresented to date. Both caffeine and nicotine belong to life style compounds, while pharmaceutical amoxicillin is one of the very popular ß-lactam antibiotics used to take care of human and animal infections. The review covers the toxic effect caused by caffeine, nicotine and amoxicillin on humans and animals and describes some of the main adsorbents utilized for their removal (e.g., grape stalk, tea waste, wheat grains, bentonite, activated carbon, acid and base modified grape slurry wastes, graphene oxides, modified graphene oxides, zeolites, etc.). The isotherm and kinetic models for the analysis of caffeine, nicotine and amoxicillin adsorption by different adsorbents are presented. The impact of pH, temperature, adsorbent dosage and thermodynamic studies were deeply analyzed. The review also discusses the mechanism of adsorption for the above-mentioned emerging pollutants, which includes π-π interaction, cation-π bonding, electron-donor and electron-acceptor forces, van der Waals forces, electrostatic interactions, etc. The present review has a potential value for chemists, ecologists, toxicologists, environmental engineers, and other professionals that are involved in environmental protection.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Adsorción , Amoxicilina , Cafeína , Ecosistema , Cinética , Nicotina
13.
J Environ Manage ; 261: 110244, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148311

RESUMEN

On-line performance indicators of a microalgae-bacteria consortium were screened out from different variables based on pH and dissolved oxygen on-line measurements via multivariate projection analysis, aiming at finding on-line key state indicators to easily monitor the process. To fulfil this objective, a pilot-scale high-rate pond for urban wastewater treatment was evaluated under highly variable conditions, i.e. during the start-up period. The system was started-up without seed of either bacterial or microalgal biomass. It took around 19 days to fully develop a microalgal community assimilating nutrients significantly. Slight increases in the biomass productivities in days 26-30 suggest that the minimum time for establishing a performant bacteria-microalgae consortium could be of around one month for non-inoculated systems. At this point, the process was fully functional, meeting the European discharge limits for protected areas. The results of the statistical analyses show that both the pH and the dissolved oxygen concentration represent accurately the biochemical processes taking place under the start-up of the process. Both pH and dissolved oxygen represented accurately also the performance of the high-rate algal pond, being affordable, easily-implemented, options for monitoring, control and optimization of industrial-scale processes.


Asunto(s)
Microalgas , Bacterias , Biomasa , Estanques , Eliminación de Residuos Líquidos , Aguas Residuales
14.
J Environ Manage ; 261: 110255, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148317

RESUMEN

Vegetation Filters (VFs) can be a sustainable solution to treat wastewater and to recover resources such as nutrients, water and biomass from small municipalities and isolated dwellings. However, under certain conditions, the leakage of nutrients, especially of nitrate, can represent a limitation. The addition of two sustainable soil amendments, woodchips and biochar, has been tested as a strategy to improve nutrient attenuation in VFs increasing sorption sites and microbial activity. To this end, unsaturated infiltration and batch experiments have been carried out at laboratory scale. The systems for infiltration experiments contain natural soil, natural soil amended with woodchips and natural soil amended with biochar. To determine the sorption capacity of NH4+, batch tests were performed using an amendment/SWW ratio of 1:20 and an NH4+ initial concentration ranging from 30 to 600 mg L-1. Results from the infiltration experiments show a high attenuation (~95%) of total phosphorous (TP) independently of the amendments. Different behaviour is observed for total nitrogen (TN). The removal of this species is obtained only in the soil amended with woodchips (>85%) whereas the natural soil alone and the soil with biochar have no impact on TN attenuation. In these two porous media, all the NH4+ input concentration is transformed to NO3- that infiltrates without further reactions. According to batch experiment results, the potential role of biochar in the nutrient attenuation is limited to sorption processes (Kd (NH4+) = 21.37-193.18 L kg-1). Woodchips act primarily as a labile source of carbon promoting biodegradation, being more effective for nutrient attenuation than the sorption capacity of biochar.


Asunto(s)
Contaminantes del Suelo , Aguas Residuales , Carbón Orgánico , Nitrógeno , Fósforo , Suelo
15.
J Environ Manage ; 261: 110265, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148322

RESUMEN

For the first time, the operational feasibility of the solar photo-Fenton process at neutral pH in continuous flow has been tested for three consecutive days. The aim of the treatment was to remove of contaminants of emerging concern (CECs) from wastewater treatment plant secondary effluents. To this end, a 5 cm-deep raceway pond reactor was run in continuous flow mode and the degradation of the CECs present in real secondary effluents was monitored at their natural concentrations. To keep dissolved iron at neutral pH, ethylenediamine-N,N'-disuccinic acid (EDDS) was used to form the complex Fe(III):EDDS as an iron source for the photo-Fenton reactions. At pilot scale the effects of the Fe(III):EDDS molar ratio (1:1 and 1:2) and hydraulic residence time (HRT) (20 and 40 min) on CEC removal were studied. The best operating condition was 20 min of HRT, giving rise to a treatment capacity of 900 L m-2 d-1 with CEC removal percentages of around 60%. The reactant concentrations were 0.1 mM Fe(III):EDDS at a 1:1 M ratio and 0.88 mM H2O2. Under these operating conditions, the short-term stability of the process was also demonstrated, thus pointing out the potential of this solar technology as a tertiary treatment.


Asunto(s)
Peróxido de Hidrógeno , Contaminantes Químicos del Agua , Compuestos Férricos , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Luz Solar , Aguas Residuales
16.
J Environ Manage ; 261: 110268, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148324

RESUMEN

Some of the microorganisms present in urban wastewater, which include intestinal protozoa and nematodes, can be pathogenic. Their (oo)cyst and egg transmissible stages are very resistant to environmental stresses and disinfectants and they are therefore difficult to remove. Thus, they can constitute a health risk if water or sludge obtained in the purification of wastewater is reused for agricultural purposes. In this context, the presence of intestinal protozoa and nematodes were studied in influents, effluents and sludge from five wastewater treatment plants (WWTPs) in the north of Spain by optical microscopy and PCR techniques. The removal efficiency of different wastewater treatments was also compared. The presence of protozoa has increased among the population discharging waste to WWTPs in recent years. Cryptosporidium spp., Giardia duodenalis, Entamoeba spp. and nematodes were detected in all of the WWTPs. Indeed, this is the first report of Entamoeba histolytica and Entamoeba moshkovskii in Spanish WWTPs. The water treatments studied showed different removal efficiencies for each species of intestinal protozoa, with the aerated lagoons providing the best results. (Oo)cysts were also detected in sludge even after aerobic digestion and dehydration. To avoid risks, (oo)cyst viability should be analysed whenever the sludge is to be used as a fertilizer. This study reinforces the necessity of establishing legal limits on the presence of protozoa in WWTP effluents and sludges, especially if reuse is planned. Further studies are necessary for a better understanding of the presence and behaviour of intestinal parasites.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Nematodos , Animales , Giardia , Aguas del Alcantarillado , España , Eliminación de Residuos Líquidos , Aguas Residuales
17.
Bioresour Technol ; 304: 123035, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32111454

RESUMEN

The aim of this study was to investigate the characteristic of a newly isolated strain Comamonas sp. ZF-3 involved in typical organics degradation in coking wastewater (CWW). The results showed that the isolated strain had efficient biodegradability of phenolic compounds and heterocyclic compounds in CWW, meanwhile, phenol and indole could be respectively used as sole carbon source for its growth, which demonstrated the bioaugmentation potential of the isolated strain in CWW treatment. During phenol and indole degradation processes, part of metabolites (e.g., 2,3-hexanedione, 2-ethyl-1-hexanol, nonanal, 2-propyl-1-heptanol, butanoic acid, butyl ester and butanoic acid, anhydride) remained in effluents, with NH4+-N concentration having no obvious reduction, which implied the biological treatment of CWW should be accomplished by complex microbial communities in many steps.


Asunto(s)
Coque , Comamonas , Fenol , Aguas del Alcantarillado , Aguas Residuales
18.
Bioresour Technol ; 304: 122959, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32135472

RESUMEN

Bioelectrochemical systems like microbial fuel cells (MFCs) are quaint systems known to metamorphose the chemical energy of organic matter into electrical energy using catalytic activity of microorganisms. A novel continuous Auto Circulating Bio-Electrochemical Reactor (AutoCirBER) was developed to fulfil the gap of 'simple, inexpensive and compact design' that can continuously treat larger amount of organic wastewater at shorter residence time and without consuming external energy for liquid mixing. AutoCirBER eliminated the need for external agitation for liquid-mixing and therefore, energy requirements. AutoCirBER was operated in continuous-mode and hydraulic retention time was optimized. The reactor underwent performance check-up viz. COD removal, net power output, columbic efficiency, sludge generation and an attributional life cycle assessment (LCA) was also conducted. AutoCirBER was sustainable to run in continuous-mode and showed more than 90.4% of COD removal, and 59.55 W.h net annual energy recovery. Experimental LCA of AutoCirBER also displays its environmental feasibility in longer run.


Asunto(s)
Fuentes de Energía Bioeléctrica , Aguas Residuales , Reactores Biológicos , Electricidad , Aguas del Alcantarillado , Eliminación de Residuos Líquidos
19.
Environ Monit Assess ; 192(4): 204, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32124056

RESUMEN

Pharmaceuticals are chemical compounds employed as medicinal drugs. They have severe physic-chemical properties which make them destructive for non-target species. Consequently, their continuous addition in the environment may pose hazardous effects. Among these, diclofenac (DCF), a non-steroidal anti-inflammatory drug (NSAID), is extensively used in Pakistan which may lead to its accumulation in both terrestrial and aquatic environment. Present study aims to assess the presence and concentration of pharmaceutically active drug (DCF) in surface water and wastewater of twin cities of Pakistan (Rawalpindi and Islamabad). For this purpose, a validated high-performance liquid chromatography (HPLC) method was adopted involving solid-phase extraction procedure. Wastewater samples were collected from various sites of Rawalpindi and Islamabad. Results of HPLC analysis revealed that DCF was extant with considerably high concentration, not only in wastewater but also in surface water samples. Concentrations as high as 216 µg L-1 was detected in Rawat industrial area and low as 8 µg L-1 was detected in dairy farm wastewater samples collected from Taramri. However, maximum DCF levels in residential wastewater and hospital wastewater were detected to be 105 µg L-1 and 34 µg L-1, respectively. Moreover, the highest detected level (116 µg L-1) was found in surface water of Sawan River. Further, results of ecological risk assessment revealed its possible toxic effects of DCF on various aquatic organisms.


Asunto(s)
Diclofenaco , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Ciudades , Diclofenaco/análisis , Ecosistema , Monitoreo del Ambiente , Pakistán , Preparaciones Farmacéuticas/análisis , Medición de Riesgo , Aguas Residuales , Contaminantes Químicos del Agua/análisis
20.
J Water Health ; 18(1): 1-7, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32129181

RESUMEN

Hospitals' effluents contain a considerable amount of chemicals. Considering the significant volume of wastewater discharged by hospitals, the presence of these chemicals represents a real threat to the environment and human health. Thus, the aim of this study was to evaluate the in vivo and in vitro genotoxicities of three wastewater effluents collected from Tunisian hospitals. The liver of Swiss albino male mice, previously treated with different doses of the hospital wastewaters, was used as a model to detect DNA fragmentation. Our results showed all the hospital effluents caused significant qualitative and quantitative hazards in hepatic DNA. The wastewater collected from Sfax hospital exhibited the highest genotoxic effect, which may be explained by the presence in this effluent of some toxic micropolluants. There was a significant increase in genotoxicity, proportionally to the concentration of effluent. However, the vitotox assay did not show any significant genotoxicity on Salmonella typhimurium TA104 in the presence or absence of microsomal fraction S9. The ratio gentox/cytox was lower than the threshold 1.5. This study assessed the toxicological risk issued from Tunisian hospital wastewaters, which is potentially very harmful, and it has been pointed out that wastewater treatment requires special attention.


Asunto(s)
Monitoreo del Ambiente/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/toxicidad , Animales , Daño del ADN , Hospitales , Humanos , Ratones , Contaminantes Químicos del Agua/análisis
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