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1.
Chemosphere ; 359: 142303, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734250

RESUMO

The world is facing water crises because freshwater scarcity has become a global issue due to rapid population growth, resulting in the need for more industries, agriculture, and domestic sectors. Therefore, it is challenging for scientists and environmental engineers to treat wastewater with cost-effective treatment techniques. As compared to conventional processes (physical, chemical, and biological), advanced oxidation processes (AOP) play an essential role in the removal of wastewater contaminants, with the help of a powerful hydroxyl (OH•) through oxidation reactions. This review study investigates the critical role of O3-based Advanced Oxidation Processes (AOPs) in tackling the complex difficulties of wastewater treatment. Effective treatment methods are critical, with wastewater originating from various sources, including industrial activity, pharmaceutical manufacturing, agriculture, and a wide range of toxins. O3-based AOPs appear to be powerful therapies capable of degrading a wide range of pollutants, including stubborn organics, medicines, and pesticides, reducing environmental and human health risks. This review sheds light on their efficacy in wastewater treatment by explaining the underlying reaction mechanisms and applications of several O3-based AOP processes, such as O3, O3/UV, and O3/H2O2. Ozone, a powerful oxidizing agent, stimulates the breakdown of complex chemical molecules by oxidation processes, which are aided further by synergistic combinations with ultraviolet (UV) radiation or hydrogen peroxide (H2O2). Notably, while ozonation alone may not always produce the best outcomes, it acts as an essential pretreatment step prior to traditional treatments, increasing total treatment efficiency. Furthermore, O3-based AOPs' transformational capacity to convert organic chemicals into simpler, more stable inorganic forms with little sludge creation emphasizes its sustainability and environmental benefits. This study sheds light on the processes, uses, and benefits of O3-based AOPs, presenting practical solutions for sustainable water management and environmental protection. It is a valuable resource for academics, engineers, and politicians looking for new ways to combat wastewater contamination and protect water resources.


Assuntos
Oxirredução , Ozônio , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Ozônio/química , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Peróxido de Hidrogênio/química , Purificação da Água/métodos , Raios Ultravioleta
2.
Foods ; 12(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36832794

RESUMO

We previously reported a sustainable food waste management approach to produce an acceptable organic liquid fertiliser for recycling food waste called "FoodLift." This study follows our previous work to evaluate the macronutrients and cation concentrations in harvested structural parts of lettuce, cucumber, and cherry tomatoes produced using food waste-derived liquid fertiliser (FoodLift) and compare them against commercial liquid fertiliser (CLF) under hydroponic conditions. N and P concentrations in the structural parts of lettuce and the fruit and plant structural parts of cucumber appear to be similar between FoodLift and CLF (p > 0.05), with significantly different N concentrations in the various parts of cherry tomato plants (p < 0.05). For lettuce, N and P content varied from 50 to 260 g/kg and 11 to 88 g/kg, respectively. For cucumber and cherry tomato plants, N and P concentrations ranged from 1 to 36 g/kg and 4 to 33 g/kg, respectively. FoodLift was not effective as a nutrient source for growing cherry tomatoes. Moreover, the cation (K, Ca, and Mg) concentrations appear to significantly differ between FoodLift and CLF grown plants (p < 0.05). For example, for cucumber, Ca content varied from 2 to 18 g/kg for FoodLift grown plants while Ca in CLF-grown cucumber plants ranged from 2 to 28 g/kg. Overall, as suggested in our previous work, FoodLift has the potential to replace CLF in hydroponic systems for lettuce and cucumber. This will lead to sustainable food production, recycling of food waste to produce liquid fertiliser, and will promote a circular economy in nutrient management.

3.
Sci Rep ; 12(1): 17207, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36241755

RESUMO

Selenium in wastewater is of particular concern due to its increasing concentration, high mobility in water, and toxicity to organisms; therefore, this study was carried out to determine the removal efficiency of selenium using iron and manganese-based bimetallic micro-composite adsorbents. The bimetallic micro-composite adsorbent was synthesized by using the chemical reduction method. Micro-particles were characterized by using energy-dispersive X-ray spectroscopy for elemental analysis after adsorption, which confirms the adsorption of selenium on the surface of the micro-composite adsorbent, scanning electron microscopy, which shows particles are circular in shape and irregular in size, Brunauer-Emmett-Teller which results from the total surface area of particles were 59.345m2/g, Zeta particle size, which results from average particles size were 39.8 nm. Then it was applied to remove selenium ions in an aqueous system. The data revealed that the optimum conditions for the highest removal (95.6%) of selenium were observed at pH 8.5, adsorbent dosage of 25 mg, and contact time of 60 min, respectively, with the initial concentration of 1 ppm. The Langmuir and Freundlich isotherm models match the experimental data very well. The results proved that bimetallic micro-composite could be used as an effective selenium adsorbent due to the high adsorption capacity and the short adsorption time needed to achieve equilibrium. Regarding the reusability of bimetallic absorbent, the adsorption and desorption percentages decreased from 50 to 45% and from 56 to 53%, respectively, from the 1st to the 3rd cycle.


Assuntos
Selênio , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Íons/análise , Ferro/química , Cinética , Manganês/análise , Águas Residuárias/análise , Água/química , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 838(Pt 1): 155608, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35504370

RESUMO

Changes in land use and land cover (LULC) due to land development can lead to an increase in diffuse microbial pollutions and, consequently, degradation of the receiving aquatic ecosystem. However, the mechanisms underlying these phenomena are rarely considered in hydrological models. Therefore, in this study, fecal indicator bacteria (FIB) and total suspended solids (TSS) in a temperate catchment were simulated using a well-established water quality model (Personal Computer Storm Water Management Model) to systematically quantify the factors influencing their dynamics and the effects of stormwater management. Additionally, high-resolution data (e.g., water quality variables and LULC changes) were used to calibrate the model, which accurately reproduced the physical and biological features of the catchment. The results showed that increases in bare land areas and impervious cover in the catchment exceeded the Korean (as well as the USEPA-based) standard recreational water quality criteria for fecal contamination and TSS. Dissolved organic compounds (only during storm events), TSS, and total nitrogen (except during the pre-development phase) were the strongest predictors in shaping FIB dynamics. The multiple control of stormwater management reduced the FIB and TSS concentrations by approximately 65% in the catchment. The results of this study not only provide conclusions on the drivers of FIB and TSS dynamics and their quantitative contribution but also help in designing a methodology for empirical and ecological predictions of diffuse microbial and TSS pollution in a catchment with ongoing land development.


Assuntos
Ecossistema , Monitoramento Ambiental , Bactérias , Monitoramento Ambiental/métodos , Fezes/microbiologia , Chuva , Movimentos da Água , Qualidade da Água
5.
Environ Sci Pollut Res Int ; 29(3): 4748-4761, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34410601

RESUMO

Pakistan has remained an energy-deficient country, and most of the industrial sectors are closed due to the loading shedding of electricity. Even though Pakistan is located on the "solar belt" and receives over 2 MWh/m2 solar irradiation per year with 1500-3000 h of sunshine, unfortunately solar energy is not harnessed to fulfill the energy needs of the country. Solar flat plate collectors (SFPC) are widely employed for collecting solar radiations from the sun. Currently, worldwide solar thermal energy is widely used in household and commercial equipment for energy collection and utilization. The working fluid selected for this research work is water; numerical simulations were performed using Ansys FLUENT. On selected geographical coordinates, solar ray tracing model was employed to incorporate solar heat flux. Nawabshah (NWB), Hyderabad (HYB), Jacobabad (JCB), and Mirpurkhas (MPK) cities were selected for the measuring of performance of SPFC. Firstly, parallel to ground (at a 0° tilt angle) orientation of SFPC was performed. Furthermore, the performance of SFPC was measured using tilt angles of 15°, 30°, and 45°, respectively. The maximum exit water temperature in JCB at a tilt angle of 30° was 97.8 °C in March and a minimum of 88.09 °C in June. In HYD, at a tilt angle of 45°, the maximum temperature rise was recorded at 98.01 °C in November and the minimum was noticed at 76.37 °C in June. While in JCA, at an angle of 30°, the highest temperature was recorded at 97.83 °C in February and a minimum of 78.54 °C in June. The specific aim of this research study was to measure the performance of the SFPC at different tilt angles and at varying geographical coordinates through numerical simulations.


Assuntos
Energia Solar , Temperatura Alta , Paquistão , Temperatura , Água
6.
Environ Sci Pollut Res Int ; 28(44): 63227-63236, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34227004

RESUMO

The increasing issue of global warming has received tremendous attention from researchers around the world as researchers are actively publishing their findings related to environmental issues such as greenhouse gas emissions, carbon footprint, and air quality. In this bibliometric review, Scopus database was accessed to retrieve publications from 1971 to 2021, related to carbon footprint of buildings which is significantly associated with global warming and air quality. The results suggested that 41% of publications were published in close access journals requiring nominal subscription fee and/or institutional permissions for access to articles. Only 1% of publications were in press for publication, while 99% of them were online available. The trend of publications on carbon footprint has increased after 2002 and is also increasing in recent years as the topic is widely studied in many fields such as environmental sciences, engineering, materials sciences, earth and planetary sciences, chemical engineering, and energy. Approximately 97% publications were peer-reviewed journal articles. The authors, i.e., Aresta, M., Lin, T.P., and Persily, A.K., published highest number of publications among all on topic of carbon footprint. However, other authors, i.e., Cai, W., Chen, Z., Ma, M. Paik, I., and Pomponi, F., have published two publications each on carbon footprint of buildings. The funding for research on carbon footprint of buildings is mainly received from the National Institute of Standards and Technology, Lawrence Berkeley National Laboratory, and Tianjin University. However, the National Taiwan University, George Mason University, and Universita degi Studi di Bari hold 3% share in total number of publications on carbon footprint of buildings. As China and the USA are countries with highest share in global carbon footprint, both countries also have highest contribution in research on carbon footprint, followed by South Korea, the UK, Japan, Italy, Germany, Taiwan, etc. The study also concluded that, due to its wider readability and understanding, most of the publications were in the English language.


Assuntos
Bibliometria , Pegada de Carbono , China , Bases de Dados Factuais , Humanos , Tecnologia
7.
Environ Sci Pollut Res Int ; 27(27): 33835-33847, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32533489

RESUMO

This study examines the performance level of hybrid woven protective clothing (HWPC), manufactured from Kevlar® (K) and Ramie (R) yarns. The weave structures (plain, twill 1/3) and variables fiber ratios were used to produce HWPC. The performance level of HWPC was measured according to EN 388:2016. We came to the conclusion that blade cut resistance of plain and twill structure sustained protection level up to increase of KR 80:20 and KR 70:30, respectively; puncture resistance of K100% and HWPC remained in the same level of protection for plain and twill weaves; Abrasion resistance of K100% and HWPC of plain and twill weaves samples presented abrasive performance of same protection level, but the average number of cycles sustained for twill weave samples was slightly higher than plain weave. However, comparing the plain and twill weaves sample for tear resistance, twill weave samples have higher tear resistance than plain weave. A gray relational analysis and Taguchi method was performed to optimize the performance of two structures with variable fiber ratios. It was established that the article produced with K&R yarns with KR 80:20 ratio and twill weave presented the best performance against all test runs. The main objective of this study is to reduce plastic pollution by reducing the amount of synthetic fiber proportion in personal protective clothing and thereby reducing the dependence on nonrenewable sources for synthetic fiber. The 41 g/m2 reduction of Kevlar® fiber has been made in a conventional PC with ramie fiber, without compromising the protection level. This will enhance the sustainability of HWPC.


Assuntos
Roupa de Proteção , Têxteis
8.
Sci Total Environ ; 663: 764-775, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30738258

RESUMO

The application and comparison of receptor modeling techniques based on ambient air quality and particulate matter increasingly being studied. However, less is known about the comparison of receptor modeling techniques using spatial runoff quality data to identify and quantify the stormwater runoff pollution. This study compared the performance of principal component analysis-multiple linear regressions (PCA-MLR) and positive matrix factorization (PMF) models on stormwater runoff data collected from a small catchment (Site 1) with urban development activity and a sub-watershed outlet (Site 2). In both sites, the PCA-MLR model identified three pollution sources, whereas PMF identified five with a detailed source mechanism including two additional sources. Furthermore, the spatial land-use land-cover (LULC) analysis results indicate that the Site 1 exhibited a rapid conversion of the native area into a built-up area over the monitoring period compared to Site 2. Based on the modeling results, domestic wastewater and soil erosion were the major source of pollution at Site 1 and Site 2, respectively. The performance evaluation statistics including Nash coefficient (0.86-0.99), % error (<-14 to 2), and coefficient of determination (R2 ≤ 0.99) showed better performance for the PMF model than the PCA-MLR model. Overall, the PMF receptor modeling approach was found to be more robust for the current study sites with different land use types. The findings of this study could provide a basis for further application of these receptor models and their comparison using spatial-temporal ionic and sediment related runoff monitoring data. Also, the models from this research could be combined with other receptor models on runoff quality data (e.g. CMB or UNMIX) to explore and inter-compare the outcomes, and to determine how the model results are affected by modifications to input data and model parameters. Therefore, further research is required to precisely assess the accuracy of both receptor models.

9.
Environ Monit Assess ; 191(2): 110, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30689056

RESUMO

The construction sites have been considered the type of land use with the highest pollution potential, especially due to the erosion of exposed soil surfaces. The runoff monitoring of the construction site was carried out since June 2011 through December 2015. Based on land use land cover (LULC) classification, the monitoring period was divided into active and post-construction phases. Total suspended solids (TSS) showed evident inter-phase variability in average annual event mean concentration (AAEMC) and wash-off pattern. We suggested that stringent runoff control measures should be adopted during active construction phase. Similarly, Personalized Computer Storm Water Management Model (PCSWMM) was applied to evaluate the performance of the time-paced discrete and composite sampling scheme in continuously changing LC scenario. It was found that even though the time-paced composite sampling scheme is more cost effective, it showed lower performance in EMC estimation when compared with the time-paced discrete sampling approach. The results also showed that the storm event monitored at a time discrete frequency of 5 min, 10 min, and 15 min, the maximum expected mean bias will be under the accepted level of 10% of the true EMC value. We concluded that construction phase-specific modifications in sampling scheme provides a view to generate near accurate estimates.


Assuntos
Monitoramento Ambiental/métodos , Águas Residuárias/análise , Movimentos da Água , Indústria da Construção , Chuva , Solo , Águas Residuárias/estatística & dados numéricos
10.
Water Environ Res ; 87(9): 813-22, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26961476

RESUMO

The monitoring of stormwater runoff from Light Rail Transit (LRT) facilities is insufficient in many regions around the world. In this study, runoff quality and quantity were monitored during operational and non-operational LRT phases during 2010-2013. The event mean concentration (EMC) of pollutants showed little statistical variability during both phases. The antecedent dry day (ADD) showed a strong to moderate positive correlation with most pollutant EMCs during the non-operational phase. The existence and magnitude of the first flush from LRT runoff was found to be similar to those from other transportation land uses. The comparison of LRT runoff data with an adjacent road bridge site showed that the pollutant EMC and unit load were 2 to 9 times higher from the road bridge. It was suggested that LRT automated operation and the elevated track makes this transportation mode a viable option for the management of non-point source pollution.


Assuntos
Ferrovias , Chuva/química , Movimentos da Água , Poluentes Químicos da Água/análise , Monitoramento Ambiental , República da Coreia
11.
Water Environ Res ; 85(3): 203-10, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23581235

RESUMO

Urban land-use areas with high imperviousness, such as bridges, highways, and parking lots, are known to be responsible for relatively large amounts of stormwater runoff and high concentration of pollutants particularly in the "first flush". This study was conducted to determine the effect of first flush from urban land-use sites located in Yongin City, Korea, on runoff amounts and pollutant concentration. It was observed that, on most pollutant parameters, the effect was apparent when the data were analyzed qualitatively but it was relatively weak when analyzed quantitatively. A stronger effect was observed from a bridge site than from a parking lot site. Pollutant loads, washed off at 40 and 60% runoff volume, respectively, were also determined for further analysis of the first flush effect to find an improved strategy for best management practices. In this study, no correlation was observed between rainfall intensity and runoff duration with first flush effect.


Assuntos
Monitoramento Ambiental/métodos , Movimentos da Água , Coreia (Geográfico) , Chuva
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