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Результаты 461-470 из 548
Heavy Metal Contamination Assessment in Sediments, Soils and Surface Waters in Agriculture-Based Rural Chhattisgarh, India, and Evaluation of Irrigation Water Quality
2023
Manash Protim Baruah, Subhajit Das, Monjil Rajkonwar and Mahesh Thirumala
Regional geochemical mapping was carried out in Bilaspur and Korba Districts of Chhattisgarh, and stream sediments/slope wash, soil, and water samples were analyzed for concentration of heavy metals. The study contributes to understanding heavy metals contamination of sediments, soils, and water due to anthropogenic activity, mainly in agriculture-based rural areas. The study reveals that high geochemical anomalies observed for heavy metals like Ni, Cr, As, and Zn in sediments and soil samples are due to the extensive uses of phosphatic fertilizer and soil amendments in the form of poultry and swine manure. Water quality assessment of major streams in the study areas shows that the water is suitable for domestic and agricultural uses. Correlation analysis reveals that the chemical weathering of rock-forming minerals doesn’t control the surface water chemistry of the study area and is also an anthropogenic source of sodium in water. This study also shows the importance of the country’s geochemical mapping database, which will have much broader applications than conventional mineral exploration and geological mapping.
Показать больше [+] Меньше [-]Assessment of SO2 Emissions from Cement Industries Utilizing Limestone with High Pyritic Sulfur Content: Case Study of Cement Plants in the Jaintia Hills District, Meghalaya, India
2023
Arnab Mandal, M. K. Choudhury, Nazimuddin and Prashant Gargava
In properly operated Cement Plants, SO2 emissions are mostly caused by pyritic sulfur (sulfides) in the used limestones, accounting for approximately 85% of the raw mill in the plant. However, the pyritic sulfur content in limestones of the Jaintia Hills district of Meghalaya and their influence on the SO2 Emission from cement industries of Meghalaya have not been studied so far. The current study is conducted to perform an in-depth investigation of pyritic sulfur content in limestone reserves used by Meghalaya Cement Industries to assess the SO2 emission in the cement industries using high pyritic sulfur limestones and review the existing technology for the recommendation of the most suitable technology to minimize the SO2 Emissions. Random testing of collected limestone samples from various locations of Captive Mining sites in Cement Industries is performed to assess average pyritic sulfur concentration along different mining benches. Pyritic Sulfur Content (wt.%) in collected limestones varies from 0.15% to 3.5%. Polynomial Regression Analysis shows that Avg.SO2 Emission(Y) from Klin Stack can be represented as a function of pyritic sulfur content (X) (wt.%) of used limestones in the process: Y = 273.7X2 + 21.46X + 422.76. Based on the pyritic sulfur content in limestones, it is observed that “the more the Pyritic Sulfur content is, Darker the Limestone Samples are.” Hence, A Colour Scale has been prepared to visualize higher pyritic sulfur content in limestones. For longer-term sustainability, installing a Flue-Gas Desulfurization (FGD) unit at the kiln stack outlet may be included in the manufacturing process of cement plants to reduce the SO2 Emissions from Stack.
Показать больше [+] Меньше [-]Fuzzy Indicators of the Forecast of Environmental Safety Taking into Account the Impact of Natural and Technosphere Factors
2023
Alexey Gordienko, Eduard Tshovrebov, Boris Boravskiy and Filyuz Niyazgulov
The emergence and uncontrolled development of environmental hazards in the processes of life in the absence of appropriate response measures in many cases leads to the emergence of man-made emergencies with dangerous consequences for public health and the environment. It is proposed to evaluate the results of complex monitoring and forecasting of these dangerous processes in a new format of creating a fuzzy scale of indicators of the level of environmental safety of life support of territories based on the theory of fuzzy sets. The study aims to develop a fuzzy scale of indicators for predicting the state of environmental protection. Protection of the population and territories from environmental threats and possible man-made emergencies. Within the framework of the purpose of the study, a fuzzy scale of threshold levels of environmental safety of territories and economic objects has been developed based on the theory of fuzzy sets and the mathematical apparatus of soft computing. The practical significance of the developments is confirmed by the successful application of the proposed scale of indicators and indicators in assessing the environmental hazard of life support systems of settlements and industrial enterprises affecting the environment.
Показать больше [+] Меньше [-]Ability of Water Lettuce (Pistia stratiotes) And Water Hyacinth (Eichhornia crassipes) To Remove Methylene Blue Anionic Surfactant (MBAS) From Detergent Wastewater
2023
N. Hendrasarie and C. Redina
ABS was the first surfactant used in detergent formulations, but because its molecular structure is branched, it is difficult to decompose biologically, making ABS a toxic compound for the environment. This study aims to remove MBAS surfactant, using a combination of phytoremediation and filtration methods to remove surfactant (MBAS) Chemical Oxygen Demand (COD) from detergent wastewater by optimizing operating factors such as pH, contact time, plant type, and filter media. Water lettuce (Pistia stratiotes) and water hyacinth (Eichhornia crassipes) were selected as plant species and silica-activated carbon was used as filter media. Water lettuce and hyacinth were grown in a 10-liter reactor with detergent wastewater samples for 6 and 12 days. Filter media are placed in the reactor in use, and aeration is done. The efficiency for reducing COD was 81.73%, and the efficiency for surfactant was 99.42% for each experiment, which was thought to be because of plant adsorption and filtering processes. The water lettuce (Pistia stratiotes) plant had the maximum adsorption capability for all the qualities evaluated, with a surfactant content in the roots of 27543.24 (mg/kg MBAS), compared to the water hyacinth plant, which only absorbed 2597.95 (mg/kg MBAS).
Показать больше [+] Меньше [-]Production of a Database on Short-Lived Climate Pollutants (SLCP) and the Elaboration of Projection Scenarios of these Emissions Using the LEAP Software - The Case of Morocco
2023
Y. Kasseh, A. Touzani and S. EL Majaty
Short-lived climate pollutants (SLCPs) have significant effects on climate, human health, and the environment. In Morocco, steps are being taken to reduce SLCP emissions, but effective policymaking requires a thorough understanding of emission sources and trends. In this paper, we present a study on the production of a database on SLCP emissions in Morocco, as well as the development of scenarios to project these emissions using LEAP software. The results of this analysis allow us to better understand the emissions sources and evaluate the impact of different emission reduction policies.
Показать больше [+] Меньше [-]Biodiesel from Dunaliella salina Microalgae Using Base Catalyzed Transesterification – An Assessment through GC/MS, FTIR and NMR Studies
2023
V. Hariram, M. Janarthanan, R. Christu Paul, A. Sivasankar, M. Wasim Akram, E. Sangeethkumar, V. Ramanathan, P. Sajid Khan and S. Manikanta Reddy
Algal biofuels are a promising renewable feedstock to produce energy that can supplement future energy demands greatly. The present study aims to utilize Dunaliella salina, a hypersaline, unicellular greenish-orange micro-algae, to produce bio-oil. F/2 nutrient media and trace metal and vitamin solution under carbon-dioxide-rich conditions were used to cultivate the microalgae. Ultrasonic extraction method at 60 Hz for 90 min isolated 650 mL of bio-oil. A single-stage based-catalyzed transesterification process with methanol and sodium hydroxide yielded 380 mL of Pure Dunaliella salina biodiesel at % an extraction efficiency of 87%. The Phytochemical screening on the cultivated Dunaliella sp. was performed to understand its feasibility to be used as a fuel for IC engines. Furthermore, the obtained biodiesel was characterized using Fourier Transform Infrared Spectrometer (FTIR), Gas Chromatography Mass Spectrometer (GCMS), and Nuclear Magnetic Resonance (NMR) spectral analysis.
Показать больше [+] Меньше [-]Assessment of the Vulnerability of Groundwater to Biological Contamination in the Khartoum State, Sudan
2023
H. B. Abbas, A. E. Elmanssury, S. A. Dafaalla and S. Arif Pasha
This study aims to determine how vulnerable groundwater in Khartoum is to contamination. For this purpose, the DRASTIC Index idea was used. A descriptive cross-sectional analytical analysis is designed in this study. A total of 279 boreholes were sampled from a total of 1015 boreholes (27.5 percent). The following criteria were utilized to define the DRASTIC Index: depth, net recharge, aquifer media, soil texture, terrain, video media, and soil conductivity. Standard bacteriological test methodologies were used for groundwater. The biological data from the 279 boreholes revealed that total coliform, thermo-tolerant coliform, and E. coli were found in 34.4 percent, 18.6 percent, and 0.36 percent of the boreholes, respectively. Bacteriological contamination is common in Sharge Elnile, although only a few cases have been reported in Khartoum. According to the study, the bulk of boreholes in Khartoum State were built without any criteria. Many sources of contamination were discovered within a radius of less than 120 meters, which was deemed to violate Khartoum State’s Environmental Health Law of 2002. For this reason, bacteriological contamination is common in Sharge Elnile, although only a few cases have been reported in Khartoum.
Показать больше [+] Меньше [-]A Comprehensive Study of Variation in Water Quality Parameters to Design a Sustainable Treatment Plant
2023
Shifana Fatima Kaafil and Shamim Shaukat Khan
In this paper, greywater samples are collected from the kitchens of different types of buildings (residential and commercial) located in different districts within the city of Jeddah, Saudi Arabia. The collected samples are analyzed and compared with the potable water from the same region. The parameters investigated are pH, conductivity, total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), total hardness, temporary hardness, permanent hardness, alkalinity, chloride, and biochemical oxygen demand (BOD). It was found that the amount of total suspended solids is very high in the greywater samples. It shows the presence of both temporary and permanent hardness. Their alkalinity values are greater than hardness. It may be due to the number, lifestyle, age of the occupants, presence of children, and social and cultural behavior of residents. The concentration of BOD level is very low, which shows that the greywater samples have lower concentrations of organic compounds. Design details of the greywater treatment plant are suggested based on the results of the analysis. This includes a screening chamber, grit chamber, settling tank, and filtration unit. The treated greywater is recommended for reuse for gardening, landscaping, and toilet flushing purposes.
Показать больше [+] Меньше [-]Carbon Emissions from Energy Use in India: Decomposition Analysis
2023
Sebak Kumar Jana and Wietze Lise
To become the fastest-growing large economy in the world, India has set a target growth rate of 9%, reaching an economy of $5 trillion by 2024-25. It is an immense challenge to meet the growth target and keep the CO2 emissions under control. The present paper aims to discover the determinants for explaining CO2 emissions in India by conducting a complete decomposition analysis, where the residuals are fully distributed to the determinants for the country from 1990-2018. The analysis reveals that the biggest contributor to the rise in CO2 emissions in India is the expansion of the economy (scale effect). The intensity of CO2 and the change in the composition of the economy, which nearly move in tandem, also contribute to the rise in CO2 emissions, although more slowly. A declining energy intensity of the Indian economy is responsible for a considerable reduction in CO2 emissions. As a typical result for an upcoming economy, this paper did not find evidence for an environmental Kuznets curve. This implies that continued economic growth will lead to increased CO2 emissions.
Показать больше [+] Меньше [-]Abundance, Characteristics, and Microplastics Load in Informal Urban Drainage System Carrying Intermixed Liquid Waste Streams
2023
K. Upadhyay and S. Bajpai
This first-of-its-kind study systematically assesses the abundance and characteristics of Microplastics (MPs) in different categories of informal open drains (nallas) carrying different liquid waste streams from different functional areas of an Indian city. Such drains are part of the informal urban drainage system that carries wastewater, stormwater, industrial effluent, and rural runoff. Logistical and locational limitations of traditional wastewater (WW) sampling methods severely limit their application in open drains. To overcome sampling challenges owing to complex geography, vast drainage network spread across different functional areas of the entire city, and local challenges, appropriately modified sampling strategies were adopted to collect samples from 35 open WW drains (small/local, intermediatory, and large). MPs (50μm-5mm) were present in a bucket, and net samples obtained from all 35 WW drains. The average MP concentration in WW drains was 4.20 ± 1.40 particles/L (bucket samples) and 5.19 ± 1.32 particles/L (net samples). A declining trend of MPs abundance was observed from larger to smaller drains, confirming that smaller and intermediatory drains (carrying WW from different functional areas of the city) are discharging their MP loads into larger drains. Intermixing different WW streams (municipal WW, stormwater surface runoff, agricultural runoff, and industrial WW) increases MP levels in drains. The local riverine ecosystem is being put at risk by a daily MPs load of 12.6 x 108 particles discharged from 9 larger drains into the local river Kharun. To protect the riverine ecosystem, controlling the high daily MPs load from such drains is important. Diversion of WW drains through constructed wetlands built near river banks can be a cost-effective solution. Because the entire Indian subcontinent and parts of Africa rely mainly on such drains having similar characteristics and local conditions, the findings of this study reflect the status and pattern of MPs pollution in informal drains of the entire Indian subcontinent and can be used by stakeholders and governments to take mitigative and preventive measures to manage the MPs pollution and protect the local riverine ecosystem.
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