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A Master Plan Realization for an Integrated and Sustainable Management System for Household and Similar Wastes in Morocco’s Landfills by Sizing a Methanation and Composting Unit Texte intégral
2023
Akram Farhat, Ayoub Aziz, Kaoutar Lagliti and Mohammed Fekhaoui
This work is a decision support contribution in Morocco’s household and similar waste management. This management based on total waste landfilling leads to several environmental impacts, such as the use of large land areas, also the gaseous pollutants released, such as methane. Our first action was to collect reference data on the composition of this waste through a physicochemical characterization in the landfill in the city of Mohammadia. We sorted the waste generated by four types of populations with different living standards. A quantity of 500 to 2315 kg was treated, which allowed us to classify the household waste studied into nine main components. The sorting results are (organic matter 54.94%, plastic 15,18%, paper and cardboard 9,72%, textiles 7,46%, sanitary textiles 5,82%, metals 2,20%, glass 1, 89%, Wood 1,82% and Other 1,28%). Thus, these results revealed organic matter dominance and an increase in the plastic rate, which did not exceed 8% in the past. Added to this, the physicochemical parameters results are (volatile matter 60,26%, Humidity rate 59,05%, a total organic carbon (TOC) 33,47%, and a lower heating value (LHV) 1840,3 kcal.kg-1). From these data, we can easily deduce that installing a sorting platform with a methanation and composting unit is the most suitable choice for recovering our waste. Therefore, we have chosen the methanation technology that meets the results obtained (dry batch and mesophilic) and sized this unit to assess its electricity production capacity that can be produced in our landfills. We carried out a scenario with a load factor of 0,9 and an electrical efficiency of 39%. The study results are 9 digesters to be built, 6.700 MW.y-1 of electrical energy produced, 14.523 tons.y-1 of refined compost, and 2.128.680 m3.y-1 of biomethane produced. By offering our own integrated and sustainable management system for household and similar waste, we have connected the landfill bins and the digesters to the same motor to avoid biogas leaks from the bins to the atmosphere and increase electrical efficiency by controlling the gas flow.
Afficher plus [+] Moins [-]Influence of Vermicomposted Coal Fly Ash on Morphological and Cytological Attributes of Ricinus communis L. Texte intégral
2023
R. U. Raval, D. B. Kapdi, N. H. Bhavsar, V. V. Surati, J. D. Solanki, S. R. Panjabi, P. M. Patel, Y. H. Vaidya, D. N. Verma and K. P. Patel
In view of the environmental problems generated by the large-scale production of fly ash, increasing attention is now being paid to the recycling of fly ash as a good source of nutrients. To reduce the cost of fly ash disposal and best utilization, it aimed to convert the fly ash into valuable vermicompost. Stated throughout the experiment, we opted for a soil sample and fly ash and pressed with different concentrations (control, 20%, 50%, 80% and 100%). Subsequently, all the mixtures were vermicomposted for 60 days by adding 100 Earthworms (Eisenia foetida) in each pile. The X-ray fluorescence spectroscopy measured the composition of the metal in fly ash as well as the nutritional content in the soil. This is followed by examining the morphological characteristics and cytogenetic study of Ricinus communis L. The present study indicated that E. foetida mitigates the toxicity of fly ash and is hence used as valuable vermicompost.
Afficher plus [+] Moins [-]Study on the Experimental Conditions of Adsorption of Lanthanum (III) on Boron Nitride Nanosheets Texte intégral
2023
C. Fu, Y. He, C. Yang, J. He, L. Sun, G. Sheng, X. Zhang, L. Wang, L. Li and W. Linghu
This paper investigated the adsorption properties of boron nitride materials for La(III), and the possible action mechanism was put forward based on experiments. Then the boron nitride materials were characterized by SEM, TEM, XRD, and FT-IR before and after adsorption. In addition, the effects of pH, the amount of adsorbent, the concentration of La(III) solution, and adsorption time on the adsorption efficiency were also investigated. It is found that under a certain amount of adsorbent when the pH is 7.0 and the concentration of La(III) is 40 mg.L-1, the adsorption ability of La(III) is the best. The maximum adsorption capacity is 201.45 mg.g-1. The adsorption kinetic data are in good agreement with the pseudo-second-order and intra-particle diffusion models. These results show that boron nitride has a good application prospect for removing and recovering La(III) in water and has a certain practical application value.
Afficher plus [+] Moins [-]Computer Vision Based Machine Learning and Deep Learning Approaches for Identification of Nutrient Deficiency in Crops: A Survey Texte intégral
2023
M. Sudhakar and R. M. Swarna Priya
Agriculture is a significant industry that plays a major role in a country’s sustainable environment and economic development. The global population demands increased food production with minimal losses. Nutrient deficiency is one of the major and crucial factors influencing crop production significantly. Common techniques for determining crop nutrition status are the diagnosis of plant morphology, Enzymology, chemical effects, fertilization, etc. However, the above techniques are invasive and time-consuming or infeasible while considering varied production practices in different locations, environments and climatic conditions. Computer Vision is an area of Computer Science that deals with creating Artificial Intelligence based vision systems that can use image data, process, and analyze as humans perform. Early Detection of Crop Nutrient deficiencies favors the farmers to monitor the affected crops and plan for the manure or fertilizer application, which supports to regain of the crop’s efficiency for attaining its maximum yield. Modern computer vision systems rely on Machine Learning (ML), Remote sensing, Satellite imagery, unmanned aerial vehicles (UAVs), Internet of things (IoT) based sensor devices, and Deep Learning (DL) models that use algorithms to extract required features from data. The objective of this work is to provide an overview of recent research and identify the scope of computer vision-based technologies used for identifying crop nutrient content and deficiency, find research challenges in predicting nutrient imbalance in comparison with plant diseases that show certain similar characteristics, thereby to improve crop health and production.
Afficher plus [+] Moins [-]Recent Advances and Sustainable Approaches Towards Efficient Wastewater Treatment Using Natural Waste Derived Nanocomposites: A Review Texte intégral
2023
K. Haroon, J. Kherb, C. Jeyaseelan and M. Sen
Pollutants like arsenic, chromium, or other toxic heavy metals have the most dreadful impact on humans or animals and also become a threat worldwide. Introducing these contaminants into the environment is not just due to the chemical industry but also coexists in combined form in underground rocks, contaminating groundwater during breakdown. Epidemics are now largely blamed on toxic pollution in many different nations worldwide. The issue has gotten worse in underdeveloped nations, where metal contamination of the groundwater affects more than a million people. Different techniques are used to remove toxic pollutants from water, but most are expensive and energy intensive. Adsorption is preferable for removing contaminants such as heavy metals or chemical dyes. As nanomaterials have been demonstrated to be more effective as nanocomposites, we used an adsorbent of nanomaterial to use the adsorption approach. These materials have become more well-liked because of their useful applications and improved characteristics. Magnetic synthesized nanocomposites have magnetic properties, which become beneficial for adsorption as it enhances adsorption capacity. The insertion of the plant or aggregate waste material for nanocomposite synthesis inhibits the growth of bacteria or other microorganisms, preventing the material from getting infected if it is in the environment. In this review paper, we have focused on the green synthesis of nanomaterials used for water treatment.
Afficher plus [+] Moins [-]Environmental Protection Measures for Unplanned Land Use and Land Cover Changes in a Subbasin of the Ganga River System Texte intégral
2023
Zeenat Ara, Ramakar Jha and A. R. Quaff
In the Ganga river system, unplanned land use land cover (LULC) changes have serious threat to the environment. Protective measures are essential at local, regional, and global scales to save human life and the environment. In the present work, the land use and land cover (LULC) changes have been studied from 2002 to 2021 in a basin area between river Gandak and river Burhi Gandak in India. For the analysis, Landsat 5, 7, and 8 satellite data have been used to analyze the changes in vegetation, urban land, open land, water body, and wet soil in the last two decades. The result shows that from 2002 to 2021 the agricultural area and open land have decreased by 16.12% (158,676 ha) and 11.85% (116794.8 ha), respectively. The urban and the waterlogged area have increased by 24.32% (240,070 ha) and 4.75% (46937.3 ha), respectively. The environmental protection measures, namely conjunctive use, multiple cropping practices, land reclamation, and decentralized urban development to reduce floating population, have been studied and recommended in the study region for better land use/land cover.
Afficher plus [+] Moins [-]Microplastic Pollution in Seawater: A Review Study Texte intégral
2023
Sheela Upendra and Jasneet Kaur
Due to its detrimental effects, notably on the well-being and biota of the ocean, microplastic contamination is becoming a bigger concern. Because of this, the issue of microplastics in the marine ecosystem is currently a major concern. The purpose of the study is to objectively evaluate the most recent data supporting the impact of microplastic contamination in seawater. When creating the standards for assessing the literature, P.I.C.O. was taken into account. For this inquiry, databases were selected and used throughout the data-collecting process. We checked PubMed, CINAHL, Google, Hinari, and the Cochrane Library. Boolean operators (AND, OR) and keywords were employed in the search to avoid oversaturating the data. Keywords used as per MeSH: Microplastic, plastics, seawater, ocean, pollution, microplastic exposure. The last five years (Since 2017) worth of studies were incorporated. Boolean search for relevant terms used. This limited my query to 188 records through various database searches. Several things were removed because they were unrelated to the study’s subject. Due to its detrimental impact on marine biota, the issue of microplastic contamination in the marine ecosystem is a current concern. Microplastics, which serve as a vector, become stuck with harmful pollutants. It is necessary to implement conservation management strategies and assistance for different educational programs to protect the environment from these hazardous microplastics. Humans are exposed to plastic waste when eating fish tainted with plastic. As a result, there are various outbreaks of chronic diseases, and people suffer the effects. The public’s education on the harmful effects of microplastics is a crucial need in this field. As a result, many inventions would be promoted to decrease the use and consumption of plastic and its products.
Afficher plus [+] Moins [-]Chemical Pretreatment of Rice and Wheat Straws to Reduce the Recalcitrant Structure: Comparative and Kinetic Studies with Different Chemicals for Biogas Production Texte intégral
2023
Nikita Kanaujia, Shalu Rawat and Jiwan Singh
In this study, a comprehensive comparison of two different chemical pretreatments of wheat straw (WS) and rice straw (RS) was made. The pretreatment was performed using piranha solution and p-toluenesulfonic acid (PTSA) to dissolve the biomass’s complex lignin and hemicellulose matrix to enhance its methane production. Energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopes (SEM), and X-ray diffraction (XRD) analysis, were used to analyze the characteristics of untreated and pretreated feedstock. WS and RS treated with piranha solution showed maximum methane yield (1234 mL and 1196 mL, respectively). The piranha pretreatment increased the methane yield of wheat straw by 2.37 folds and rice straws by 2.31 folds. The maximum VFA concentration was observed in WS on the 14th day in the piranha-treated sample, 1553.33 ± 2.8 mg.L-1, while in RS on the 21st day in the untreated sample, 676 ± 5.77 mg.L-1. SEM analysis of piranha-treated WS indicated a reduction in recalcitrant structure. Deformation of C-O, C=C, C-C-O, and C-H bonds in cellulose, hemicellulosic, and lignin as a result of chemical pretreatment in WS and RS was also indicated by FTIR analysis. The modified Gompertz model (MGM) and logistic function model (LFM) appropriately defined the degradation process and explained cumulative biogas’ kinetic. Pretreatment with piranha solution reduces the complexity of WS and RS, thus increasing methane production by reducing the retention time.
Afficher plus [+] Moins [-]Effect of Elevated Ozone on Soybean (Glycine max L.) Cultivar: Role of Orange Juice and Synthetic Ascorbic Acid Texte intégral
2023
Indra Jeet Chaudhary, Bhavna Nigam and Dheeraj Rathore
Ozone is a hazardous gas for the environment and negatively affects plant and human health. These days, phytoextracts are commonly used as a source of bioactive compounds for reducing the detrimental environmental effects on plants. In the presented study, soybean cultivar JS-335 was used to assess the protective role of synthetic ascorbic acid (SAA) and orange juice (25% orange juice, enriched ascorbic acid) under ozone stress conditions. The results showed that under ozone stress, soybean cultivar JS-335 reduced growth and biomass and negatively affected the biochemical properties of plants due to these changes, finally causing yield losses. Foliar-applied OJ >and SAA improved plant growth and development and increased crop yield. It was discovered that a 25% OJ coupled with ascorbic acid and other essential nutrients and biomolecules was almost as effective as a 100 ppm SAA in reducing the harmful effects of ozone stress on soybean plants. As a result, it was determined that OJ, a less expensive source of ascorbic acid, can improve ozone resistance in plants in ozone-prone areas.
Afficher plus [+] Moins [-]Occurrence of Heavy Metals in Soil and Selected Edible Plants in the Vicinity of Major Lead-Zinc Mining Sites in Ebonyi State, Nigeria Texte intégral
2023
E.B. Ogbuene, O.G. Aloh, C.T. Eze, O.O. Eze, T.E. Ugochukwu, A.M. Oroke, C.E. Izueke-Okolo, A.V. Ozorme, C.J. Ibekwe and C.A. Eze
The occurrence of heavy metals in soil and selected edible plants (Manihot esculenta, Dioscorea rotundata, Ipomoea batatas, Telfairia occidentalis, and Chromolaena odorata) in the vicinity of major Lead-Zinc mining sites in Ebonyi State, Nigeria was investigated. The concentrations of the detected heavy metals in soil from the study sites ranged from 0.38-77830.99 (mg.kg-1). The limit values for all detected metals in soil from the mining sites were exceeded in most instances. The results showed that the plant species accumulated heavy metals near the mining sites to varying levels in their shoots and roots. The limit values for all detected heavy metals in the edible plants were not exceeded except in a few instances. The plant species demonstrated varying effectiveness for phytoextraction, indicating their appropriateness in the phytoremediation of heavy metal-contaminated soil. Therefore, examining the environmental consequences of uncontrolled mining activity in the vicinity of the mining sites with a scientific approach has helped to increase our knowledge of the pollution problem in the mining sites, reveal the ferocity of the situation, and contribute to the techniques presently in use for monitoring chemical pollution in a mining-impacted ecosystem.
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