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Detection of Microplastics in Drinking Water Treatment Plants in Baghdad City/Iraq
2023
H. Sultan, Hassan | Abdul Wahab Shaker Al-Aadhami, Mohammad | Nihad Baqer, Noor
Microplastics are an emerging environmental pollutant detected in different environments, but studies in Iraq are rare, if not nonexistent. Our research aims to detect the presence of microplastics in raw water and drinking water treatment plants in Baghdad. Water samples were collected (1 liter per sample) from four drinking water treatment plants: Al-Fahama station, Al-Fath Al-Mubin station, Al-Dora station, and Al-Madaen station, which receive water from the Tigris River. The microplastic shape was determined by a fluorescent microscope examination after staining with Nile dye. FTIR spectrophotometer used to determine microplastic compounds. The results showed, according to FTIR examination, that the most critical types of microplastic compounds in water samples were Nylon, Polycarbonate, High-density polyethylene, Polystyrene, Polyamide, Polyethylene terephthalate, and Polyurethane, and Microplastics number were (17-62 MPs /L) in raw water, while in drinking water were (9-40 MPs/L). The fibers form is the predominant form of microplastics in natural and drinking for stations: Al-Fahamah (91.6%, 66.6% respectively), Al-Fath Al-Moubin (58.8%, 77.7% respectively ), Al-Doura (65.3%, 52.5% respectively), Drinking water in Al-Madaen station (40.0%). At the same time, the spherical shape is predominant in the raw water of Al-Madaen station (82.2%).In conclusion, the current study indicated the pollution of drinking water treatment plants with microplastics.
Показать больше [+] Меньше [-]Sustainable Energy Transition for Cities Based on Long-Term Planning Supported by a Fuzzy Cognitive Map
2023
Eftekhar, Alireza | Yazdanpanah Dero, Qiuomars | Zaker Esfehani, Alireza
The present study was aims to explore resilience and transformation capabilities and explore their applicability in the field of energy. It focuses especially on the role of the cognitions of stakeholders and decision-makers in the uptake and management of sustainability transitions. Fuzzy cognitive mapping (FCM) is used to aggregate different stakeholders’ views on the functioning and performance of the urban energy system of the city of Tehran. In the case of Tehran, the urban energy network is analyzed in terms of resilience and transformability by studying the degree of connectivity and its influence on both system characteristics. Three scenarios of policy options are simulated to weight their outcomes in terms of sustainability, Scenario A: Optimization of economic incentives; Scenario B: Strong education and awareness campaigns; and Scenario C: Stronger local institutional initiatives. Scenario A shows a potential perverse effect if the current economic structure is maintained, even if the economic crisis is overcome. Combining Scenarios B and C provides the best results in terms of sustainability. This suggests that successful transformation in cities should pivot on a combination of top-down and bottom-up actions to unlock resilient but unsustainable states, and that special care needs to be taken when managing highly connected and/or influential elements of the system, as contextual dependencies might hinder the agency of change, particularly in the context of cities. Network characteristics, such as connectivity, can be useful indicators to inform resilience and transformation management, although the double-edge sword nature of connectivity should be noted.
Показать больше [+] Меньше [-]Use of Eggshell as a Low-Cost Alternative Adsorbent for Elimination of Fluoride from Groundwater
2023
Assami, Zakaria | Messaitfa, Amar
This paper aims to study the possibility of providing a low-cost alternative for the adsorbents used in the fluoride adsorption from water by using eggshells. Indeed, eggshells were used as an adsorbent for fluoride adsorption from a drinking groundwater sample containing (2.14 mg/l) of fluoride. The eggshells were crushed and sieved into three particle sizes (0.2, 0.5, and 1mm) and then heated at different temperatures ranging from 100 to 250°C. XRD, FT-IR, pHpzc, and TG/DTA analysis were used for the characterization of the adsorbents. Adsorption batch experiments were carried out to determine the adsorption capacity of eggshell powder such as, particle size, preparation temperature, contact time, and adsorbent dose. A spectrophotometer UV-VIS was used to assess fluoride removal efficiency. The eggshell powder heated at 250°C with 0.2mm of particle size was found to be the most efficient adsorbent, with a maximum fluoride removal efficiency of 51.4%, a maximum adsorption capacity of 0.052mg/g, and a residual fluoride concentration of 1.1mg/l within 150 minutes. The data of the adsorption kinetic on ES250°0.2 were successfully fitted with the pseudo-second-order model with a satisfying coefficient of determination (R2=0.993). The results of the intra-particle diffusion model showed a multi-linearity, revealing that the diffusion of fluoride into the adsorbent was by two stages with diffusion rate constants of Ki = 0.007 (mg /g/min1/2) and Ki = 0.001(mg /g/min1/2) for the first and second stage respectively. An adsorbent dose of 1.5g and 1 hour of contact time were sufficient to decrease fluoride concentration from 2.14 to 1.1mg/l.
Показать больше [+] Меньше [-]Assessment of Environmental Hazard and Heavy Metal Contamination in Dhaleshwari River Sediment: A Toxicity based Study on Pollution
2023
Islam, Md. Al Sadikul | Hossain, Mohammad Enayet | Nahar, Kamrun | Majed, Nehreen
Developing nations, such as Bangladesh, face an enormous crisis in maintaining natural sustainability due to heavy metal contamination by the peripheral rivers. Frequent heavy metals discharged from tanneries, dyeing, and potential anthropogenic activities in Savar city pollute the Dhaleshwari river, which is an important river of the capital city, Dhaka. The present study aimed to assess the heavy metals contamination in the Dhaleshwari river sediment and evaluate the subsequent ecological risk indices emerging from the deposits. The contamination levels of heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) were analyzed in the Dhaleshwari River sediment. Various environmental indices, such as Potential Enrichment Risk (PER), Geo-accumulation Index (Igeo), Enrichment factor (EF), Toxic unit analysis (TUs), etc., were observed in various compartments. The concentration of heavy metals ranged as follows: Lead (Pb), 297.3-414.6 mg/L; Cadmium (Cd), 1.5-4.4 mg/L; chromium (Cr), 97.9 -282.4 mg/L; Nickle (Ni), 85.1-264.5 mg/L; Iron (Fe), 11800-14375 mg/L. The metal concentrations were higher than the threshold effect level (TEL) and probable effect level (PEL) standards. Based on the TUs, the probability of toxicity is about 76% (TU > 2.3) at the Dhaleshwari river. Comparative evaluation of different environmental indices between present and past studies indicated progressive deterioration of sediments by heavy metals. Linear correlations of heavy metals in sediment samples demonstrated toxic accumulation of heavy metals in the surrounding ecosystem. The study outcomes emphasize the necessity of systematic investigation in the Dhaleshwari river and warranting effective prioritization to ensure river health over industrial wastewater discharge.
Показать больше [+] Меньше [-]The Rhizospheric Soil of Sparganium erectum L. Plant: A new Source of Efficient Bacteria for Azo Dye Decolorization
2023
Nikkhah, Masoumeh | Pourbabaei, Ahmad Ali | Shariati, Shayan | Shakiba, Mina
The purpose of our study was to identify the native bacteria with the ability to degrade azo dyes from the rhizosphere of Sparganium erectum L., and Typha latifolia L. plants that were grown on a drain of a textile mill. Eight and one strain with decolorization ability of Cibacron Brilliant Red EB and Terasil Red 3BL-01 were isolated from the saline rhizosphere of Sparganium erectum L. and latifolia L. plant respectively. Results showed that the bacteria isolated from the rhizosphere of Sparganium erectum L. are more capable of decolorizing azo dyes. Based on the 16S rRNA sequencing, selected strains were identified as follows: Enterobacter ludwigii strain SNP3 (OL719291), Rhodococcus fascians strain SNP5 (OL759129), Pseudomonas aeruginosa strain SNP10 (OL759126), and Bacillus safensis strain SNP13 (OL759127). The results of azo dyes biodegradation tests revealed that strains SNP10, SNP3, and SNP5 were more capable of decolorizing 94-97%, 72.53-73.8, 72.53%, and 71.13-73.5% of Cibacron Brilliant Red EB at concentration 10-20 mg/L within 72 h, respectively. Besides, strain SNP13 was the fastest strain in decolorization of Cibacron Brilliant Red EB with 68% and 59% decolorization activity at 10 and 20 mg/L respectively (24 h). Only strains SNP3 and SNP13 could decolorize 83% and 77% of Terasil Red 3BL-01 (30 mg/L), respectively. For the first time, our research findings illustrated that indigenous rhizospheric bacterial strains isolated from Sparganium erectum L. plants have the potential to apply as an azo dye breakdown tool in textile effluent treatment or other ecosystems.
Показать больше [+] Меньше [-]Assessment of Concentration and Distribution of Contaminants Using Magnetic Susceptibility Measurements
2023
Anis, Naushi | Kumar, Arun | Arya, Ajay
Magnetic properties are used throughout the world to measure the concentration of (ferri) magnetic minerals in soil, sediment and dust. These minerals in soil come from a variety of sources, including air-borne particulate pollution, parent rock and paedogenesis. Changes in the content of magnetic minerals, as well as their spatial and vertical distribution in soil profiles are caused by human activity. Magnetic minerals are distinguished by their affinity for other elements found in soil, such as heavy metal. As a result, magnetic susceptibility has been widely used as an approximation of heavy metal contamination in soil. The current study was conducted in a tropical deciduous forest in Central Uttar Pradesh, namely the kukrail reserve forest in Lucknow to assess heavy metal contamination levels caused by various anthropogenic activities and to confirm the utility of using MS surveying in these types of studies. The current study was conducted at two sites viz. agricultural area and forest area because these sites are the most contaminated ones. Significant correlation between heavy metal concentration and magnetic susceptibility with p<0.005 is noticed for Co, Cr, Pb, Zn, Cu and Fe of agricultural area. Similarly in forest area significant correlation exists between Cr, Ni, Pb and Zn. The χLF values show a significant correlation with the concentration of heavy metals except for Cu and Cr in forest area and Pb and Zn in agricultural area. In comparison to the methodologies of chemical analysis, the χLF measurement techniques provide us with lower cost and less time consuming method for identification of possible soil pollution.
Показать больше [+] Меньше [-]Greening of brick and tile production: an index to evaluate its environmental performance
2023
Oliveira, Leandro | Rebelato, Marcelo | Saran, Luciana
This work presents an index to evaluate the environmental performance of brick and tile manufacturing. The steps used were: 1) process study; 2) waste analysis; 3) determination of the potential impact of waste; 4) normalization of the potential impact; 5) comparative weighting among the potentials; 6) creation of the index. The index considers three parameters: the amount of waste produced, the disposal of waste, and the spatial dispersion of waste. The index was called CIRI (Ceramic Industry Rating Index) and was tested in a ceramic company. The field application showed that the waste that offered the highest environmental impact were gases generated from the burning of chips (30.850%), ashes generated from the burning of chips (30.483%), and steel drums (28.937%), which total of 90.27%. The CIRI index was 28.732%, which shows bad waste management. In view of the findings, two points must be considered: 1) the impacts generated by gaseous could be mitigated by companies by using technologies for drying tiles and bricks with a lower level of environmental impact; 2) entrepreneurs should be concerned about the fate given to the ashes because the dispose practiced is not environmentally correct. The index is useful for assessing the environmental impact of the brick and tile industry. It is useful for managers insofar as a proposal for process improvements. The novelty of this study lies in the index developed, which was designed to consider: the potential for environmental impact, the amount of waste, the spatial coverage, and the adequacy of waste disposal.
Показать больше [+] Меньше [-]Life Cycle Assessment of Crude Oil Processing by Energy Management Approach
2023
Naseri, kioumars | Noorpoor, Alireza | Razavian, Fatemeh | Khoshmaneshzadeh, Behnoush
The first future challenge facing human beings is to supply the world's energy needs. However, energy consumption and resource depletion in industrial processes are significantly increasing. Therefore, life cycle assessment can be an excellent tool to quantify resources and energy consumption in different parts of industrial processes. The combination of process simulation and assessment of process life cycle can be resources & energy consumption in different parts is quantified and can be significantly reduced by optimizing the process, energy wastage. The process stimulation is done by HYSIS software, then by collecting output data, energy and materials flow, life cycle assessment is conducted using SIMAPRO software. According to output of the release list, 1709 items are released into the environment, of which 396, 407, 340 items are released into the air, water, soil, respectively and 556 items are extracted from sources. The most appropriate procedure to assess the life cycle of crude oil processing is Cumulative Energy Demand and Cumulative Exergy Demand energy approach. Based on the first-order analysis, the highest consumption of resources and energy is in the crude oil transmission sector; (Road construction with 44.95 petajoules and transmission pipelines with 19.85 petajoules). Also, regarding the second-order analysis, the highest consumption of resources and energy is related to crude oil production processes with 1.65 petajoules per operation and desalination unit, medium voltage electricity consumption with 0.002194 petajoules and exergy of power lines with 0.00087 petajoules.
Показать больше [+] Меньше [-]Interspecies Peculiarities of Biomarkers Response of Marine Fish Embryos to Oil Pollution
2023
Rudneva, Irina
Shelf areas of the seas and oceans characterizing high productivity are the spawning sites of many aquatic organisms. However, they are strong impacted for anthropogenic pollution, including oil contamination, which negatively influence on marine organisms. The effects of mazut and diesel fuel in the concentrations of 0.05, 0.1 and 0.2 ml/l on the activity of antioxidant enzymes which are recognized as biomarkers of the oxidative stress namely superoxide dismutase (SOD), catalase (CAT), peroxidase (PER) and glutathione reductase (GR) in the developing embryos of two marine blennies Parablennius sanguinolentus and Salaria pavo (Perciformes: Blenniidae) on the V - VI developmental stages were studied. The results demonstrated higher mazut toxicity as compared with diesel fuel. In P. sanguinolentus embryos exposed to mazut the activity of key anti-oxidant enzymes SOD and CAT were significantly higher (+413% and +100% as compared with the control, p<0.05), while in the case of diesel fuel the enzymes level varied insignificantly. In the embryos of S. pavo SOD and CAT activities were also increased at mazut incubation (256% and 103% respectively, p<0.05), while the differences between enzymes level in embryos exposed to diesel fuel were lower. In contaminated S. pavo embryos enzyme activities varied less as compared with the embryos of P. sanguinolentus, therefore they are more resistant and adaptive to oil contamination. The possible mechanisms of fish embryos antioxidant system response to oil pollution are discussed.
Показать больше [+] Меньше [-]Review on Naphthenic Acids: An Important Environmental Pollutants Caused by Oil Extraction and Industries
2023
Sotoudeh, Yaser | Niksokhan, Mohammad Hossein | Karbassi, Abdolreza | Sarafrazi, Mohammad Reza
Naphthenic acids are a group of polar organic carboxylic acids that are present in crude oil naturally. They are cycloaliphatic carboxylic acids which have 10 to 16 carbons, which gained importance since the early twentieth century because of corrosion in oil refineries. Moreover, they are the most important environmental pollutants caused by oil extraction from oil sand reserves. Heavy crude oils which have high concentration of naphthenic acids are usually considered as poor-quality oil and sold at a lower price. Often, the high concentration of naphthenic acids in crude oil reduces the life of the equipment which are used in the exploration and refining process because of corrosion. Hence, researchers are increasingly interested in the chemical properties of naphthenic acids and the acidic components of the crude oils. The most popular methods for the identification and analysis of naphthenic acids are liquid and gas chromatography (GC), liquid-liquid extraction, Fourier transform infrared spectroscopy (FTIR), and solid-phase extraction (SPE). Naphthenic acids are the most important environmental pollutants caused by oil extraction from oil sand reserves. Previous studies have revealed that naphthenic acids can be absorbed by fish, but their distribution in different tissues of fish has not been specified. Experimental samples showed the highest toxicity to fish, while there was less toxicity to invertebrates and algae. Moreover, naphthenates have various industrial utilizations; they are used in synthetic detergents, corrosion inhibitors, lubricants, fuel and oil additives, wood preservatives, insecticides, fungicides, pesticides, wetting agents, napalm thickening agents, and oil desiccants that are utilized in painting and treating wood surfaces.
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