خيارات البحث
النتائج 11 - 20 من 532
Feasibility Analysis of Municipal Wastewater Reinjection Technology
2024
Haijie Hu, Huan Zhang, Lei Han, Le Zhang, Tao Yu and Chengtun Qu
To study the feasibility of using municipal sewage as a reserve water source for oilfield reinjection, the water sample treated by the municipal sewage treatment plant and the produced water of the Chang 2 reservoir were taken as the research objects. Through the analysis of water quality and compatibility, the optimal ratio of reinjection water samples was determined. At the same time, the clay swelling experiment and reservoir damage experiment were carried out. The experimental results show that the salinity of municipal sewage is low, and the content of scale ions is low. When the ratio of produced water to municipal sewage is 7:3, the scale formation amount can reach 42.5 mg.L-1, and when the scale inhibitor is added, the scale formation amount can be reduced to 10.4 mg.L-1. The mixed water sample will not cause clay expansion. Meanwhile, Chang 2 reservoir is moderately weak water sensitive and weak acid sensitive. The oil content, suspended solids content, and median particle size of the mixed water sample during reinjection should be controlled at 5 mg.L-1, 5 mg.L-1, and 5 μm to ensure that the reinjected water sample does not cause damage to the reservoir.
اظهر المزيد [+] اقل [-]Determinants Influencing the Environmental Impact Assessment Compliance Rate by Industries in Aba City, Southeast, Nigeria
2024
C. Sam-Amobi, O. J. Ubani, K. Efobi and Nathan Ajukwara
A United Nations (UN) report on the severity of pollution in cities around the world in 2020 rated Aba City, Nigeria, as the most polluted city in the world. This has become a source of worry and embarrassment for environmental policymakers in the country. The matter of whether industries are efficiently managing their wastes came to the fore, and policymakers questioned the compliance of these industries with environmental laws and Environmental Impact Assessment (EIA) guidelines and the reasons behind the seemingly non-compliance of the industries with these guidelines. The study aimed to investigate the determinants that influence compliance with EIA guidelines by industries in Aba. A survey research method was employed in the study. Questionnaires and interviews were also used to elicit data from industrialists and environmentalists in the study area. 384 industries were sampled in the study. Principal Component Analysis was used to test the hypothesis. The study revealed seven factors that influenced the compliance rate of EIA guidelines by industries, and they include weak public participation (65.5%), ignorance (54.5%), an effective legal system and legislation (42.4%), the cost of compliance (40.5%), weak coordination along the line of departments (town planning officers and consultants) (35.5%), delay in approval (30.5%), and limited scope (28.9%). It was recommended that the government strengthen the legal system as it relates to the implementation of EIA; then, there is a need to involve affected stakeholders in the preparation of EIA documents.
اظهر المزيد [+] اقل [-]Sustainability Analysis of Landfill Cover System Constructed Using Recycled Waste Materials by Life Cycle Assessment
2024
G. Sanoop, Sobha Cyrus and G. Madhu
The sustainability of using industrial by-products for the construction of landfill cover was determined using Life Cycle Assessment (LCA). LCA was carried out on four materials: sand- bentonite mix, red earth- bentonite mix (amended soil), Waste Foundry Sand (WFS)- Bentonite mix, and WFS- marine clay mix. The former two are commonly used cover soils and the latter two are alternative materials proposed. Environmental impacts based on the extraction of resources, processing, transportation to the site, and site preparation were considered using the ‘cradle to site’ approach. Analysis was carried out in OpenLCA software using the ReCiPe (H) Midpoint method of impact assessment. Required data for analysis was taken from the Ecoinvent database supplemented with inputs from a field survey. The use of WFS in landfill cover systems was found to be sustainable using LCA studies when compared to conventional materials.
اظهر المزيد [+] اقل [-]Passivation Effect of Corn Vinasse Biochar on Heavy Metal Lead in Paddy Soil of Pb-Zn Mining Area
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.
اظهر المزيد [+] اقل [-]Enhancing Enzymatic Hydrolysis and Delignification of Sugarcane Bagasse Using Different Concentrations of Sodium Alkaline Pretreatment
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.
اظهر المزيد [+] اقل [-]An Investigation in Temperature Data Analysis of Middle Atmospheric Variation from SABER Satellite
2024
E. Raghavendrakumar, V. Kamalakar and K. Sunil Kumar
This paper focuses on significant data analysis for middle atmospheric variations of height of 0 km 100 km. This data was downloaded from the SABER satellite NASA and analyzed with the help of MATLAB. The analysis includes the determination of propagation of wavelengths and oscillations for the semi-annual oscillation (SAO), Annual oscillations (AO), quasi-annual oscillations (QBO), EINIO southern oscillation (ENSO) from the period of Jan 2002 to Dec 2022 past twenty years data. The monthly mean Temperatures, monthly ozone deviations, and overall mean temperatures with standard deviations are estimated for the following altitude regions concerning troposphere (0-20km), stratospheric (21-50 km), mesospheric (51-90 km), and thermospheric regions (91-105 km). However, the results proved that the maximum temperature variations would affect the ozone depletion for the areas concerning the altitude height of 15-40 km region between troposphere and stratospheric in the temperature range of 260K, and average deviations are found in the order of 0.000010 μm for the troposphere region. The presence of harmful gases such as CO, CO2, NOx, H, and CH4 released from the automobile and powerplant industry may deplete the ozone layer and cause adverse effects.
اظهر المزيد [+] اقل [-]Effect of Humic Acid Fertilizer on Mercury Release from Greenhouse Soils
2024
Z. Zhao, L. Y. Long, H. Gu and R. G. Sun
The elemental mercury (Hg0) release characteristics from the Hg-contaminated soil applied with Humic acid fertilizer (HAF) in the greenhouse were identified. The adsorption features of mercuric ion (Hg2+) on HAF under different reaction times and pH were investigated to elucidate the influencing mechanism of HAF on soil Hg0 release. Besides, the microstructure of HAF loading with Hg2+ was characterized by using Fourier transform infrared spectroscopy (FTIR) and scanning electron micrograph-energy dispersive spectrometry–EDS). The results showed that with the increasing HAF dosage, soil oxidation-reduction potential (Eh), and organic matter (SOM) content, as well as the decreasing soil pH, the soil Hg0 release fluxes showed a decreasing tendency. The soil pH, Eh, SOM, and total Hg content are the key factors that can affect the soil Hg0 release fluxes. The interior air temperature, light intensity, soil moisture, and soil temperature have little impact on soil Hg0 release fluxes when the greenhouse soil is applied with HAF. The HAF can immobilize Hg2+ and reduce its activity by surface precipitation and specific adsorption, then affecting the soil Hg0 release fluxes. The results of this study provide a basis for the application of HAF to reduce soil Hg0 release fluxes in the greenhouse of Hg-contaminated areas.
اظهر المزيد [+] اقل [-]Impact of Cadmium-Induced Stress on Physiological Traits with Induced Osmolyte and Catalase-Mediated Antioxidative Defense in Rice (Oryza sativa L.)
2024
J. Yomso and A. Siddique
Cadmium is one of the most carcinogenic and hazardous heavy metals on the earth for causes many serious diseases and disorders in the plant body. The presence of Cd in the soil is equally harmful to the production of rice crops and human beings. A pot experiment was conducted to analyze the consequences of cadmium-induced stress on the antioxidative defense system in rice plants. The assessment of antioxidative defense mechanism based on the cadmium-induced stress in the range of 100 to 300 ppm while the parameters, Chlorophyll Content Index (SPAD), nitrogen (%), relative water content (%), membrane stability index (%), proline content (μg.g-1), and catalase activity (nm H2O2 mg-1.min-1) were used. The highest reduction in the Chlorophyll Content Index (CCI), nitrogen (%), RWC (%), and MSI (%) was recorded at the highest concentrations of Cd Cl2 (300 ppm). However, at the same time, an increase in proline content (μg.g-1) and catalase activity (nm H2O2 mg-1.min-1) were also detected at all the intervals of the study. The activity of CCI, amino acid, and enzyme were presented in % increase/decrease over the control of Cd-induced stress in rice plants. The reduction (%) in CCI (SPAD) and RWC (%) was recorded maximum at 75 Days after transplanting (DAT), while nitrogen (%) and MSI (%) were recorded at 50 DAT. However, the increase (%) in proline and Catalase activity was maximum at 75 and 50 DAT.
اظهر المزيد [+] اقل [-]Why Renewable Energy Gained Attention and Demand Globally?
2024
S. As’ad
Energy security and stable supply are the most important aspects for any nation. The rising need for energy, caused by both population growth and economic activity, is a problem for many nations throughout the world. Consequently, they have to find a way to meet energy demand while also making sure it is inexpensive and sustainable. The use of renewable energy has gradually become one that is being given a lot of attention since it does not cause any harm to the environment. On the other hand, renewable energy is gaining popularity for a variety of different reasons. A paradigm shift toward renewable resources is relevant, as they have the ability to lessen reliance on fossil fuels and decrease environmental consequences; this article will provide several reasons why renewable energy is attracting attention on a global scale. Indeed, renewable energy is plentiful, clean, and might one day provide all of our energy needs. A country's carbon footprint and reliance on fossil fuels may be reduced by investing in renewable energy sources. In addition, there are several health and environmental problems associated with air and water pollution; nevertheless, renewable energy may assist decrease these problems.
اظهر المزيد [+] اقل [-]Knowledge, Attitude, and Practices on Climate Change Among Rice Farmers in Central Luzon, Philippines
2024
E. N. Farin, R. R. Sazon, R. A. Sazon, D. V. Rogayan Jr., K. B. Manglicmot, S. G. Mendoza and E. M. Cabal
The Philippines has been listed as the topmost affected country by climate change. One of the sectors affected by this climatic change is the agricultural sector. This study aimed to document the knowledge, attitude, and practices (KAPs) on climate change among rice farmers as a baseline study in disseminating the practices on disaster risk reduction management to rice farmers in Central Luzon to reduce risks and improve the rice yield and income of rice farmers. A total of 969 respondents were randomly sampled from the seven provinces of Central Luzon. A survey questionnaire and an unstructured questionnaire were used as instruments in gathering the needed data. Descriptive and thematic analysis were used in analyzing the data. Results revealed that rice farmers are knowledgeable and have favorable attitudes toward the impact of climate change on farming. They sometimes practice climate-smart agricultural practices. Generally, the farmers are affected by weather and climatic conditions as well as the hazards that cause a reduction in rice yield. Climate change has affected farmers in their social well-being, economic aspect, and rice production. In terms of climate change disaster adaptation measures, the farmers sometimes adopt measures in terms of flood and drought and seldom adopt measures in typhoons, erosion, and volcanic eruptions. The study recommends the conduct of capability training on disaster risk reduction in rice production (such as early planting and planting of high-yielding varieties) based on the specific needs of each province.
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