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Evaluating Domestic Wastewater Treatment Efficiency of Field Scale Hybrid Flow Constructed Wetland in Series Texto completo
2024
Vishwakarma, Smily | Dharmendra, Dharmendra
Constructed wetlands (CWs) are man-made systems designed to treat a range of residential, commercial, and industrial wastewaters. The objective of the study was to evaluate the efficiency of wastewater treatment systems using constructed wetlands. The effectiveness of removing chemical and physical pollutants was also evaluated. The setup consisted of a hybrid flow system composed of upflow constructed wetland and a horizontal flow constructed wetland connected in series that is used for primary treatment of the influent of domestic wastewater. Two systems were analyzed: one cultivated with the ornamental species Canna Indica, and one cultivated with the cattail Cymbopogon flexuosus. It consisted of two treatment sections consisting of two plant species Cymbopogon citratus (lemon grass – first CW) and Canna xalapensis Horan (Canna Indica – second CW). The water quality parameters i.e., BOD, COD, TSS were analyzed according to APHA (American Public Health Association) by daily sampling. The CW was monitored for the quality of wastewater inflows and outflows and nutrient accumulation in plants. Results showed that the maximum COD removal for Lemon Grass and Canna Indica beds were 75% and 70% respectively at 200mg/L COD loading in the CW setup over a six-month period respectively. The maximum BOD removal found in Lemon Grass and Canna Indica beds were 73% and 64% respectively at a feed concentration of 200mg/L COD. Both the CWs together as one unit showed similar rates of TSS removal irrespective of the type of wetland plant species and were more efficient in treating wastewater.
Mostrar más [+] Menos [-]Properties of the Nuisance Dust Particles in Sulaymaniyah City, Northeastern Iraq Texto completo
2024
Othman Abdulla, Shahen | Souri, Bubak
Nuisance dust particles have emerged as a significant environmental concern within the Middle Eastern region. The principal aim of this research was to conduct an extensive investigation into the physical and chemical attributes of dust-fall particles located within the city of Sulaymaniyah, northeastern Iraq. Over a period of six months, a total of 72 dust-fall particle samples were systematically gathered from three distinct stations, with intervals of seven days. In addition to quantitative analysis, this study included detailed morphological examinations and mineralogical composition assessments, facilitated through the application of analytical methodologies, including Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). The outcomes of these analytical procedures revealed predominantly irregular shapes of the dust particles, characterized by the presence of quartz and calcite minerals, confirming their natural origin due to wind-driven erosion originating from the arid desert landscapes of Iraq and its neighboring southern and western countries. Moreover, this investigation extended to encompass a comprehensive evaluation of both water-soluble and insoluble fractions, in addition to the overall concentration levels of alkali and alkaline earth metals including sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg). Furthermore, the levels of heavy metals of manganese (Mn), iron (Fe), copper (Cu), and arsenic (As) were investigated. The extent of pollution associated with these elements was assessed through the application of the Geo-accumulation index (Igeo) which revealed that, during the study, calcium, magnesium, and copper demonstrated noticeable levels of contamination within the dust-fall particles of Sulaymaniyah city.
Mostrar más [+] Menos [-]A Case Study of Extreme Temperature with Air Pollution and Health Risk in Yazd Province during July 2019 Texto completo
2024
Fazel-Rastgar, Farahnaz | Khansalari, Sakineh | Sivakumar, Venkataraman
This investigation aims to study synoptic analysis in the dynamic structure accompanied by air pollution of extreme heat during July 2019 in the Yazd province. The time-series data analysis for the yearly surface air temperatures during the past two decades shows a significant peak surface air temperature in July 2019 in Yazd province. The long-term mean and anomalies of the daily basis (2001 to 2019) for the daily mean sea level pressure show a decrease in pressure with a maximum of about 6 hPa and an increase in geopotential height at 500 hPa with a maximum of about 20-30 gpm (geopotential meter), which has led to an increase in the average daily temperature of about 2 to 4 degrees Celsius. Also, showed high values for Ozone mass mixing ratio over the study area mostly over the west with a maximum of ~92 ppb in Yazd province on 1 July 2019. The AIRS (Atmospheric Infrared Sounder on NASA's Aqua satellite) data shows a positive trend (2003- 2019) for the total daytime Ozone column-averaged over the study area during July. Furthermore, the results of this work obtained from OMI satellite observation show a significant increase in the ultraviolet aerosol index (UVAI) during the study period time. This study shows the recent extreme weather changes in the study area which may be necessary for a better future forecast for heat warnings along with poor air quality and health risk when such events may happen in the future.
Mostrar más [+] Menos [-]A Simulation to Assess the Probability of the Spread of Radioactive Materials from the Zaporizhzhia Nuclear Power Plant using the HYSPLIT Model Texto completo
2024
Valizadeh, Behshad | Heydarizade, Yassin | Tayebi, Javad | Rezaie, Mohammad Reza
Today, world pollution is increasing, and many pollutants such as radioactive elements enter to environment through human activity contaminants play an essential role in human life and health. Therefore, the examination of models for dispersion caused by radioactive substances is an important issue. This article is a simulation study of the hypothetical scenario of the Zaporizhzhia Nuclear Power Plant (ZNPP) in Ukraine, which is one of the NPPs in Europe. This scenario includes the occurrence of an accident in the power plant that entry of pollutants to environment and creates an environmental disaster. The simulation of this scenario was done using the Hyspli4 )Hybrid Single-Particle Lagrangian Integrated Trajectory) model and NOAA website data of ZNPP (include the wind information, temperature, humidity, and atmospheric pressure in different spatial and temporal scales) to predict and deal with pollutants. The simulation was conducted in the first week of April 2023 for 131 I and 137Cs elements, which are important elements that come out of the power plant and cause many problems. The results show the highest annual dose and concentration are 4.6 mSv/year and 2.7E+06 Bq.s/m3 respectively. It also shows that in the event of pollution, the entry of contaminated materials into the Dnieper River and the western edge of the blackened sea will bring a great disaster. Also, the eastern and northeastern regions of Ukraine, especially Kharkiv and the western borders of Russia, lead to pollution that causes radiation hazard, so the news should be shared with everyone before an actual incident occurs.
Mostrar más [+] Menos [-]The Impact of Surfactant on Aquatic Ecosystems: A Study on Biochemical Alterations in Clarias gariepinus Induced with Linear Alkylbenzene Sulfonates Texto completo
2024
Ikpesu, Thomas Ohwofasa
The toxicity of linear alkylbenzene sulfonates (LABs) to Clarias gariepinus was investigated. For 30 days, the fish were exposed to LABs at 0.00, 0.50, 1.00, 1.50, and 2.00 mg/L. After each trial period, one fish from each plastic tub was chosen and its heart was punctured for blood samples. The blood samples were then collected and deposited in pre-designated bottles for analysis. Following blood collection, a fish was dissected and its organs were extracted. The organs were preserved in liquid nitrogen at -25oC until they were analyzed. A portable refractometer was used to quantify total serum protein content. A microplate reader was used to measure reduced glutathione (GSH). Albumin was quantified using the Bromocresol Green albumin assay kit, whereas alanine aminotransferase activity was assessed colorimetrically. Subtracting albumin from protein concentration yielded the globulin content. On days 23 and 30, protein content corresponds positively with exposure length and differs significantly (p < 0.05) between the control and treatment groups. The activity of GSH reduced slightly but not significantly (p > 0.05). Significant variations in albumin and globulin (p < 0.05) only on day 30. AAS activity differs significantly (p < 0.05) between treatments and the control. This study demonstrated that LAB exposure can be harmful to human health. Because anthropogenic sources are the primary source of LAB exposure, authorities must implement strict mitigation measures to limit this risk.
Mostrar más [+] Menos [-]Characteristics of microplastics in the sludge of wastewater treatment plants Texto completo
2024
Kamani, Hossein | Ghayebzadeh, Mehdi | Ganji, Fatemeh
In recent decades, one of the environmental concerns is contamination with emerging pollutants of microplastics. Microplastics enter the environment through wastewater treatment plants and can absorb harmful pollutants. This study investigated microplastic pollution in the sludge of Zahedan wastewater treatment plants. To investigate microplastic pollution in the sludge of Zahedan wastewater treatment plants, 5 kg samples of sludge were passed through stainless-steel sieves and digested using H2O2 solution. NaCl was used based on density to separate microplastics. FESEM and FTIR analyses were used to investigate the surface morphology and polymer type of microplastics. The abundance of microplastic particles in the sludge ranged from 71-95 N/Kgdry.sludge, and their size varied from 25-500 micrometers. The most common color observed was transparent, and the fiber shape was the most prevalent. The study highlights the importance of addressing microplastic pollution in wastewater treatment plants to prevent harmful effects on the environment. Also, the data obtained from this study can be used to improve the treatment process and understand the removal of microplastics in urban wastewater treatment plants.
Mostrar más [+] Menos [-]Trace metal exposure and health concerns in Bangladeshi rivers: a seasonal comparison of the Buriganga, Shitalakhya, Meghna, Karnaphuli, and Padma rivers' water, sediment, and fish Texto completo
2024
Hasan, Nahid Bin | Fahad, Md. Abu | Zahid, Abdullah-Al | Hasan, Mahadi | Rahaman, Ashiqur | Hossain, Sakhawat | Sarker, Tama Rani | Hossain, Mohammad Nazmul | Khatun, Nazma
We determined the levels of nine heavy elements in water, sediment, and the edible tissues of three frequently eaten fish species collected from the five polluted rivers in different divisions of Bangladesh. These samples were randomly taken from five rivers and analyzed by Flame Atomic Absorption Spectroscopy. We found seasonal fluctuations in the hierarchy of mean concentration for different heavy metals in five rivers’ fish, water, and sediments. In the water, the concentrations of Cd, Cr, Cu, Fe, Mn, Pb, Zn, Ni, and Hg ranged from 0.010-0.081, 0.016-5.531, 0.013-2.445, 0.860-22.924, 0.043-1.424, 0.015-0.933, 0.091-1.451, 0.012-2.888, and 0.010-0.032 mg/l where in the sediment the concentrations ranged from 0.1-1.47, 4.21-284.1, 0.12-28.46, 1860-14971.33, 122.1-480.8, 0.84-42.15, 2.14-210.35, 15.3-30.4, and 0.17-10.44 mg/kg. For fishes concentrations ranging from BDL-0.78, 0.04-86.45, 0.01-1.67, 4.19-102, 0.08-0.94, 0.01-0.99, 0.08-9.56, 0.01-4.56, and BDL-0.2 mg/kg were reported for the above metals order respectively. The highest concentration (mean) of Cr and Fe in waters and sediments was 1023 times and 13020.72 % higher than WHO’s standard and Toxicity Reference Values (TRV), respectively. Besides, the bioaccumulation factors (BAF) of the selected elements for the studied fishes were found to be between 0.036-626.25, where the pollution load index (PLI) for the five rivers ranged from 0-0.95 and the concentration factor (CF) found between 0.02-4.03. Estimated daily Intake (EDI) as well as Target hazard quotients (THQs) analyses revealed potential risks for fish consumers, particularly the level of some metals exceeding the WHO/FAO's tolerable limit, which indicates that the rivers' water and fish are dangerous to humankind.
Mostrar más [+] Menos [-]A comparison between two polychaete species; Marphysa gravelyi and Dendronereis aestuarina in terms of heavy metal accumulation from three differently polluted mangrove ecosystems of Northern Kerala, India. Texto completo
2024
Jithin, Kothalil | Dinesh, Kaippilly
Three separate mangrove ecosystems in Kerala's Kannur district were examined for trace metal build-up in sediment and two polychaete species, Marphysa gravelyi and Dendronereis aestuarina. By classifying the areas according to the intensity of anthropogenic activity, metal deposition in polychaete tissue was investigated. ICP-MS was used to assess the heavy metal load and the accumulation of metals in sediment in the range of, Zn 24.37-59 mg/kg, Ni 23.67- 59.25 mg/kg, Cu 11.27- 38.6 mg/kg, Pb 4.5- 16.4 mg/kg, Cd 0.1-1.8 mg/kg, Fe 1.25- 3.67 %, and Al 0.65-2.43 %. The soil sample's Zn concentration was at its highest and heavy metals accumulated in the pattern Zn˃Ni˃Cu˃Pb˃Cd. By just switching the concentrations of Ni and Cu, polychaetes' trace metal concentrations follow the same pattern as those found in soil, however, M. gravelyi was discovered to have larger amounts of accumulation when compared to D. aestuarina, mostly for metals like Zn and Pb. Based on data compiled from all stations, the average concentration of accumulation for Zn was 62.34 mg/kg & 43.45 mg/kg, and for Pb, it was 6.59 mg/kg & 1.86 mg/kg in M. gravelyi and D. aestuarina, respectively. Most metal buildup is found in mangrove soil, which has higher levels of organic carbon and clay particles. The findings imply that D. aestuarina is an organism that is sensitive to pollution and that M. gravelyi is a species that is extremely tolerant of pollution, suggesting that the species can be used to anticipate the state of its surrounding environment.
Mostrar más [+] Menos [-]Evaluation of heavy metal contamination in sediments of the Umayo Lagoon, Peru, and the behaviour of local actors Texto completo
2024
Atilio Salas-Ávila, Dante | Chaiña Chura, Fermin | Belizario Quispe, German | Quispe Mamani, Edgar | Hurtado Chavez, Edgar | Rojas Chahuares, Felix | Quispe Borda, Wenceslao | Hermoza Gutierrez, Marian | Salas Mercado, Dante
Multidisciplinary studies that integrate socioenvironmental aspects into the assessment of water resources contamination significantly enhance the identification of its sources. In the present study, an assessment of heavy metal contamination in sediments of Umayo Lagoon and the behavior of local actors was conducted. The concentrations of As, Cd, Cu, Hg, Pb, and Zn were determined and evaluated using international regulations. These data enabled the creation of distribution maps to pinpoint accumulation zones of different metals and suggest their possible sources of origin. The results were compared with the behavior of local actors, addressing three analytical characteristics: feelings, thoughts, and attitudes. Evidence showed contamination by As (18.11 mg/kg), Hg (0.19 mg/kg), and Cd (0.96 mg/kg), likely originating from mining activities, cheese plants, and agriculture. In terms of social aspects, intense emotions were expressed due to the presence of diseases and livestock mortality associated with metal contamination, causing anxiety and fear in the population. The incorporation of socioenvironmental aspects in the contamination assessment aligned with the physicochemical results, achieving identification of the sources of Umayo Lagoon.
Mostrar más [+] Menos [-]Removal of Benzyl butyl phthalate by Polyetheretherketone/polyvinylalcohol nanocomposite Modified with Zinc oxide nanoparticles Adsorbent from Wastewater Texto completo
2024
Cheraghi, Reza | Abrishamkar, Maryam | Jalali Jahromi, Hossein | Hoseini, Farzaneh
The applicability of Polyetheretherketone/polyvinylalcohol nanocomposite modified with zinc oxide nanoparticles synthesis for the removal of benzyl butyl phthalate from wastewater. Identical techniques, including BET, FT-IR, XRD, and SEM, have to characterize this unknown material. The investigation shows the applicability of adsorbent PEEK/PVA/ZnONPs, as an available, suitable, and low-cost adsorbent for adequately removing the benzyl butyl phthalate from wastewater. The impacts of variables, including benzyl butyl phthalate concentration, adsorbent, pH, and time (15 mgL-1, 0.3 g, 5.0, and 60 min). Based on the received data, the adsorption of benzyl butyl phthalate on the PEEK/PVA/ZnONPs adsorbent agrees well with the Langmuir adsorption model isotherm (qm = 34.24 mgg-1). The results of the thermodynamic parameter showed a negative enthalpy (-77.0 KJ/mol), a negative Gibbs free energy (-11.7 KJ/mol), and negative entropy (-274.0 J/K.mol). This led to the conclusion that the adsorption process is energetically possible, and exothermic was also spontaneous. This work indicates that the PEEK/PVA/ZnONPs, used as an ecologically adapted, adsorbent holds promise for eliminating benzyl butyl phthalate from wastewater.
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