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Study on the Technology of Ultrasonic, Chemical and Mechanical Combined Treatment of Oilfield Aging Oil Texto completo
2024
Le Zhang, Jin Hu, Longlong Yan, Si Chen, Yabin Jin, Huan Zhang, Zhe Shen and Tao Yu
Aging oil is a common pollutant in petrochemical enterprises due to its severe emulsification and flocculation, poor settling performance, low oil recovery rate, and high difficulty in treatment. This article adopts the method of mechanical, ultrasonic, and chemical coupling demulsification to treat aging oil, with the water content and oil recovery rate of the treated aging oil as the inspection indicators. The experiment shows that when the oil-water ratio is 1:4, the heating temperature is 50℃, the stirring speed is 180rpm, the ultrasonic frequency is 25kHz, the power is 40W, the ultrasonic time is 25min, and the pH is adjusted to 3-4. The additional amount of FeSO4 is 160mg/L, the additional amount of H2O2 is 0.11%, and the heating stirring reaction is 40min. When the dosage of cationic PAM with an ion degree of 50 is 35mg/L, the centrifugation speed is 3200rpm. The centrifugation time is 20 min, the crude oil recovery rate after aging oil treatment can reach over 94.6%, and the water content of the treated crude oil is less than 0.5%, meeting the standards for crude oil gathering and transportation in China. The oil content in the water generated after aging oil treatment is about 150 mg.L-1, the suspended solids content is 200 mg.L-1, the oil content in the residue is 6%, and the water content is 53%. By analyzing the appearance of aging oil before and after treatment, it was found that when using this process to treat aging oil, the original spatial cross-linking network structure of the aging oil was broken, allowing the water droplets wrapped in the oil to be released, thereby significantly reducing the water content in the recovered oil and improving the oil recovery rate.
Mostrar más [+] Menos [-]Passivation Effect of Corn Vinasse Biochar on Heavy Metal Lead in Paddy Soil of Pb-Zn Mining Area Texto completo
2024
M. Xiong, G. Q. Dai, R. G. Sun and Z. Zhao
The in-lab incubation experiments were conducted to identify the passivation effect of corn vinasse biochar, which was prepared at different temperatures, on heavy metal Pb in paddy soil of the Pb-Zn mining area. The results showed that after 30 days of biochar amended to the soil, the soil pH and organic carbon content increased by 2.72%-8.47% and 27.79%-65.26%, respectively. The CO32- and OH- contained in corn vinasse biochar could react with Pb and generate carbonate and hydroxide of Pb. In comparison with the treatment control, the bioavailable fractions of Pb were reduced by 26.6%, 23.30%, 26.95%, and 35.33%, respectively, in biochar-amended treatments. Exchangeable fractions of Pb decreased by 21.50%, 21.33%, 22.58%, and 22.58% for the treatment 3% (300°C), 6% (300°C), 3% (600°C), and 6% (300°C) corn vinasse biochar, respectively, compared with the treatment control. As a whole, corn vinasse biochar could effectively promote the transformation of Pb in soil from the exchangeable fractions into the Fe-Mn oxide-bound fractions and residue fractions, with a significant passivation effect for Pb in soil and more effective passivation by high-temperature preparation and increased dosage of biochar.
Mostrar más [+] Menos [-]Urban Indian Environment in the Context of a Pandemic Texto completo
2024
Abhijith. S., Akshara S. N. and P. P. Nikhil Raj
The spread of the Coronavirus disease 2019 (COVID-19) has impacted human life severely since November 2019. The urban centers in the world, especially, were highly affected by the diseases. Several socioeconomic and environmental factors probably enhanced the spread of the pandemic and consequent mortality. Many studies examining environmental factors, such as air quality, in urban centers indicate the roles of those factors in the spread of diseases and consequent mortality. However, other socioeconomic factors that directly or indirectly elevate the mass death of people are seldom studied. The present study explores the socioeconomic factors and air quality influencing COVID-19 deaths in urban India. We randomly selected 19 Indian cities and collected each city’s socioeconomic and air quality data from reliable and open sources. The data were analyzed using multivariate data analysis techniques using R statistics. The results showed significant positive relationships, population, and total area of the urban centers.
Mostrar más [+] Menos [-]Enhancing Enzymatic Hydrolysis and Delignification of Sugarcane Bagasse Using Different Concentrations of Sodium Alkaline Pretreatment Texto completo
2024
Arti Yadav, Pushpa Rani, Deepak Kumar Yadav, Nisha Bhardwaj, Asha Gupta and Narsi Ram Bishnoi
Lignin, being highly resistant, needs to be eliminated in the process of extraction of soluble reducing sugar and bioethanol production from lignocellulosic biomass. In the present work, pretreatment of sugarcane bagasse (SCB) was performed using NaOH of various concentrations (1-5%) to facilitate delignification. The hydrolysis efficiency of pretreated SCB was evaluated at different reaction times by the production of reducing sugar using the Cellic CTec2 enzyme. The maximum cellulose content of 57.6% and lignin removal of 62.04% were observed with 2% sodium hydroxide at 121°C autoclaved for 60 min. The hemicellulose content decreased with increasing NaOH concentration with the maximum decrease of 13.6% from native bagasse having 26.5% xylan content. The microstructure, morphology, and chemical composition of SCB were analyzed using Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform InfraRed (FTIR), and XRD. The hydrolysis with 10 FPU.g-1 of enzyme at 48 h of reaction time shows a maximum yield of 12.34 g.L-1 corresponding to 55.53 ± 0.45% at 2% NaOH pretreated SCB. This study claims that lignin components exhibited the highest susceptibility to NaOH pretreatment, which directly affects enzymatic hydrolysis.
Mostrar más [+] Menos [-]Machine Learning-based Calibration Approach for Low-cost Air Pollution Sensors MQ-7 and MQ-131 Texto completo
2024
L. R. S. D. Rathnayake, G. B. Sakura, N. A. Weerasekara and P. D. Sandaruwan
Air quality is a vital concern globally, and Sri Lanka, according to WHO statistics, faces challenges in achieving optimal air quality levels. To address this, we introduced an innovative IoT-based Air Pollution Monitoring (APM) Box. This solution incorporates readily available Commercial Off-The-Shelf (COTS) sensors, specifically MQ-7 and MQ-131, for measuring concentrations of Carbon Monoxide (CO) and Ozone (O3) ,Arduino and "ThingSpeak" platform. Yet, those COTS sensors are not factory-calibrated. Therefore, we implemented machine learning algorithms, including linear regression and deep neural network models, to enhance the accuracy of CO and O3 concentration measurements from these non-calibrated sensors. Our findings indicate promising correlations when dealing with MQ-7 and MQ-131 measurements after removing outliers.
Mostrar más [+] Menos [-]Integrated Riverside Development Along Adyar River, Chennai Texto completo
2024
S. Indhu Kirthika and R. Shanmuga Priyan
Integrated Riverside Development (IRD) is a planning approach that aims to achieve sustainable development of urban areas located along riverbanks. To implement this IRD with controlled regulations, the study is focused on developing a comprehensive riverside development and river zoning regulatory framework that integrates all five main elements, with particular emphasis on economic, ecological, and social factors, in order to reduce encroachment and pollution in the study area. The objectives of the study include analyzing the current land use, recreational parks, encroachments, pollution levels, sewage disposal patterns, and solid waste dumping zones in the study area, as well as studying the socio-economic and eco-environmental aspects of the area. Additionally, identifying and analyzing the major threats to the river and developing a river zoning regulatory framework using the land use matrix technique is also included in the study objectives. The study area (Adyar River) was chosen based on social, ecological, and economic factors, and data was collected through surveys and from government offices. Using the land use matrix method, proposals for riverside development were made, and the zones were classified into development-prohibited, development-restricted, and development-optimized zones. The zones were classified based on the calculated values of Eco sensitivity for each of the three zones. Proposals were then given based on these classified zones, and the levels of development potential were determined. The proposed zoning regulatory framework is expected to have a significant impact in reducing further encroachments and improving connectivity between the city and the river. By considering socio-economic, ecological, and environmental aspects, the study recommends appropriate zoning regulations for riverfront developments that promote sustainable growth.
Mostrar más [+] Menos [-]Determination of Mycotoxigenic Fungi and Total Aflatoxins in Stored Corn from Sites of Puebla and Tlaxcala, Mexico Texto completo
2024
K. Saez-Gomez, R. Avila-Sosa, M. Huerta-Lara, F. Avelino-Flores and R. Munguia-Pérez
This paper aimed to evaluate the contamination with mycotoxigenic fungi and total aflatoxins in stored corn from different sites in Puebla and Tlaxcala, Mexico. Methodology. The study was conducted at two sites in Puebla (San Salvador El Seco and Junta Auxiliar La Resurrección) and two sites in Tlaxcala (Tlaltepango and Nativitas). A total of 80 samples of stored corn were collected. Identification of Aspergillus flavus was performed by microculture techniques and specific taxonomic keys (macromorphological and micromorphological). Then, samples of contaminated corn were selected, and aflatoxin production was confirmed using a direct solid-phase ELISA kit. A total of 25 A. flavus strains were identified. Other possible mycotoxin-producing fungi were Penicillium (n=52) and Fusarium (n=19). Regarding total aflatoxin contamination, all samples were contaminated within a range of 1.589 to 11.854 μg/kg, and the average concentration was 6.3 μg/kg corn. Implications. The detection of mycotoxigenic fungi in the samples tested and of aflatoxins in corn highlights the importance of monitoring these fungi. Since food safety is at risk, it shows the need for methods to control these fungi and their metabolites.
Mostrar más [+] Menos [-]The Global Clothing Oversupply: An Emerging Environmental Crisis Texto completo
2024
M. S. Neethu and R. Bhuvaneswari
Fashion is a potent visual indicator of our times, almost a language that speaks for us and something popular or in style, a zeitgeist. Fashion, specifically fast fashion, has gained prominence in discussions about fashion, sustainability, and environmental awareness. The speed of the hedonic treadmills continues to increase exponentially, and the so-called fast fashion has won legions of young fans who can snap up relatively cheap clothes online, but the trend masks darker environmental problems. Concerns about the fashion industry’s environmental impact have increased in recent years. This realization was prompted by accumulated evidence of a rise in clothing consumption due to greater availability and affordability. This shift has fostered not only heedless and hasty clothing consumption but also heedless and hasty clothing disposal. This article attempts to elucidate the relationship between humans and the environment. It also tries to incorporate the concepts of sustaincentrism and traceability to pave the way for sustainable development. This study employs an experimental survey method to ascertain consumers’ perceptions of sustainable fashion and to assess the implications of their current purchasing behavior. The SPSS software is used to analyze the data’s reliability, and regression analysis was employed to determine the fashion industry’s environmental impact. The survey results indicate optimism for a rise in ethical business strategies and the adoption of sustainable approaches within the fashion industry, thereby establishing a green economy.
Mostrar más [+] Menos [-]Impact of Small Anaerobic Digester on Household Economy of Bangladeshi Livestock Farmers Texto completo
2024
N. Sultana, J. S. Khanam, K. S. Huque, B. K. Roy, N. Huda and M. K. Alam
An extensive survey was performed covering all the regions of the country to find out the overall impacts of bio-digester on the economy of livestock farmers. Five districts were selected; ten farmers with having bio-digester of 3.2 m3 on average and ten farmers who have no bio-digester were selected from each district. Through direct interviewing and farm monitoring, all farm characteristics, i.e., diurnal biogas production, power generation, cooking time, income and expenditures, farmer’s gross earnings, and manure management practices data were collected accordingly. Descriptive statistics and student t-test was made to express the comparison response of the farms by using XL and SPSS software. It was observed that the owners of anaerobic digesters earned significantly (p < 0.001) more than the traditional farmers by selling animals and biogas (1715 & 306; 1146 & 0.00 USD, respectively). Not only that, by selling milk and fresh manure, the owners of bio-digester harvested more (p < 0.05) annual income than non-bio-digester farmers (4162, 3408 & 60.91, 44.63 USD, respectively). Though the expenditure of farmers having digester was high, but in a single fiscal year, they earned more (p < 0.05) profit than the conventional farmers (USD 4329 & 2842, respectively). However, owners of bio-digester used 67.2 % of their produced manure for gas production. Regarding storing manure as biomass and using it for cooking purposes significant difference (p < 0.001) was observed that was also reflected in the total manure management system of a farm. The farmers having no bio-digester stored 71.95% of their total manure in solid form, whereas the farmers who had bio-digester only stored 20.4% of their manure, which made a significant (p < 0.001) difference. From the biogas chamber, in an average one farmer used a gas stove for 4-5 hours and a gas lamp for 6-8 hours, which saved at least the expenditure of 18 USD per month/household. The notable thing was that the bio-digester alone contributed 7% to those farmers’ gross economy by producing gas. It can be recommended that the rural householders could generate power by installing bio-digester and turn a small bio-digester as a beneficial avenue of their household economy.
Mostrar más [+] Menos [-]Selection of White-Rot Fungi for Decolorization of Palm Oil Mill Effluent and Evaluation of Biodegradation and Biosorption Processes Texto completo
2024
Sanhathai Ridtibud, Nuttika Suwannasai, Apichaya Sawasdee, Verawat Champreda, Cherdchai Phosri, Sarper Sarp, Nipon Pisutpaisal and Siriorn Boonyawanich
Ten species of white-rot fungi were evaluated for their ability to decolorization of palm oil mill effluent. The highest decolorization efficiency was found with Trametes elegans (PP17-06), followed by Ganoderma sp.2 (PW17-06) and Ganoderma sp.2 (PW17-177), respectively. T. elegans was further evaluated for the long-term performance of decolorization for 24 d. The optimal retention time for the decolorization was 8 d, with a color removal efficiency of 47.7%. Beyond 18 d of incubation, decolorization efficiency was reduced due to the autolysis of enzymes. During the biodegradation process, manganese peroxidase enzyme activities reached a maximum of 36.03 U.L−1. However, no significant laccase and lignin peroxidase activities were observed. T. elegans was also assessed for decolorization performance through biosorption on mycelial biomass. The synthesis of the enzyme was prevented by exposing the mycelium to HgCl2. Within an optimal contact time of 2 d, decolorization efficiency reached 12.5% with ADMI reduction from 4259.0 (±20.1) ADMI to 3727 (±104.04) ADMI. Results indicate that the adsorption capacity was reached at this time, and no significant color removal can be achieved by biomass. Results obtained in this study showed the potential of T. elegans in decolorizing palm oil mill effluent.
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