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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.
Afficher plus [+] Moins [-]Evaluation of the Contaminated Area Using an Integrated Multi-Attribute Decision-Making Method
2024
A. Mohamed Nusaf and R. Kumaravel
Air pollution affects public health and the environment, creating great concern in developed and developing countries. In India, there are numerous reasons for air pollution, and festivals like Diwali also contribute to air contamination. Determining the polluted region using several air contaminants is significant and should be analyzed carefully. This study aims to analyze the air quality in Tamil Nadu, India, during the Diwali festival from 2019 to 2021, based on multiple air pollutants. The study models the impact of air pollution as a Multi-Attribute Decision-Making (MADM) problem. It introduces a hybrid approach, namely the Analytical Hierarchy Process-Entropy-VlseKriterijumska Optimizacija I Kompromisno Resenje (AHP-Entropy-VIKOR) model, to analyze and rank the areas based on the quality of air. A combined approach of AHP and entropy is employed to determine the weights of multiple air pollutants. The VIKOR approach ranks the areas and identifies the areas with the worst air quality during the festival. The proposed model is validated by performing the Spearman’s rank correlation with two existing MADM methods: Combinative Distance Based Assessment (CODAS) and Weighted Aggregates Sum Product Assessment (WASPAS). Sensitivity analysis is carried out to assess the effects of the priority weights and the dependency of the pollutants in ranking the regions. The highest air pollution level during the festival was seen in Cellisini Colony (2019), Rayapuram (2020), T. Nagar and Triplicane (2021) in their respective year. The results demonstrate the consistency and efficiency of the proposed approach.
Afficher plus [+] Moins [-]Water Resource Impacts of Irrigation: The Case of the Main Irrigation Canal from the M’Pourie Plain to Rosso in Mauritania
2024
Mewgef El Ezza dite Hanane Djieh Cheikh Med Fadel B. A. Dick, E. C. S’Id, M. B. Ammar, Y. M. Sidi, L. S. Mohamed, A. Semesdy, M. L. Yehdhih and M. Fekhaoui
An important factor in determining agricultural production is the availability of irrigation water in the main canal of the M’Pourie plain. This factor affects both the intensification of crops and the size of the irrigation areas. The main Senegal River canal in Rosso, Mauritania, runs across the Plaine of M’Pourie. This study aims to assess the physicochemical quality of the water used for irrigation and agriculture in the main irrigation canal on the M’Pourie plain. The measurements were made from 2021 to 2022, and the following physical and chemical parameters were monitored: pH, temperature, electrical conductivity, salt content, calcium, magnesium, sodium, and potassium; ammonium bicarbonate; chloride; nitrite; nitrate; nitrogen; sulfate; and sodium adsorption ratio (SAR). These measurements were analyzed using volumetric, spectroscopic, and spectrophotometric methods. After conducting statistical analysis and comparing the results with Moroccan quality standards for surface water utilized in irrigation, it has been discovered that the average pH value is 7.51, indicating a neutral state. However, the average nitrite and ammonium values exceed Moroccan standards at 5.16 mg.L-1 and 0.41 mg.L-1, respectively. The water’s low mineralization is attributed to its low electrical conductivity, with an average of 52.2 μS.cm-1. Based on the analysis of the Senegal River water used for irrigation in the M’Pourie plain, it has been determined that its sodium adsorption ratio and electrical conductivity classify it as belonging to class C1S1. This indicates that the water has low salinity and is excellent for irrigation, with a low risk of alkalinization.
Afficher plus [+] Moins [-]Threshold Effect of Trade on Climate Change in South Africa
2024
Teboho J. Mosikari and Kesaobaka Mmelesi
The relationship between trade and climate change is not a simple linear relationship. In this paper, using the threshold regression model, we estimated the effect of trade on climate change in South Africa. The paper applied the LM test to examine the nonlinear inference approach to test whether nonlinearity existed and if the threshold model was relevant to the study. The results show that when energy use is set as the threshold variable, the relationship between trade and climate change measured as methane is U-shaped. Also, in other models of GHG as climate change indicators, the results show that the effect of trade on climate change is not dynamic. This result supports the idea that high and low trade effects may have different impacts on climate change indicators. It is, therefore, recommended that all exporters in South Africa resort to more innovative environmental mechanisms to reduce the contribution to climate. The suggestion for future studies is to consider exports of different sectors to climate change. This approach will avoid the generalization of exporting firms as the worst emitters.
Afficher plus [+] Moins [-]Recent Progress of Novel Porous Materials in Wastewater Treatment
2024
Deqi Kong, Hua Chen, Zhen Xiang and Bin Wang
Unavoidably, the expansion of industry causes the release of numerous heavy metals, radionuclides, and organic pollutants into the environment. Due to these pollutants, the extremely toxic, highly carcinogenic chemicals provide a serious risk to people and aquatic life. Wastewater pollutants must be removed to safeguard the ecology. A huge specific surface area, multiple binding sites, a plethora of functional groups, variable pore size, and simplicity of surface modification are just a few advantages of porous materials. They are considered viable candidate materials for the efficient and selective removal of contaminants from aqueous solutions in a range of difficult circumstances due to their benefits. This work reviews the characteristics, methods of functionalization, and ways of modification of many novel porous materials in recent years. The use of these porous materials in the treatment of wastewater was examined. The development potential of porous materials is finally summed up.
Afficher plus [+] Moins [-]Competitive Adsorption of Cd(II) and Zn(II) on Biochar, Loess, and Biochar-loess Mixture
2024
Y. W. Li, B. W. Zhao, L. Wang, Y. Q. Li, T. Wang, Y. H. Jia and M. L. Zhao
Combined heavy metal contamination in soil is a common phenomenon. Biochar amendment into the soil is considered to be an alternative for immobilization remediation of soil contaminated with heavy metals due to its adsorption and alkalization. However, much attention has been paid to the adsorption and immobilization of single heavy metals by biochar. In this paper, the competitive adsorption of Cd(II) and Zn(II) on biochar derived from cotton straw and pig manure at 500℃ (BCS500 and BPM500), loess and biochar-loess mixtures were investigated using the batch equilibrium method. The results showed that the adsorption capacities of biochars, loess, and biochar-loess mixtures to Cd(II) and Zn(II) in the mixed Cd-Zn systems increased with the increase of initial metal concentrations of Cd(II) and Zn(II). The adsorptive capacities of BCS500 and BPM500 to Cd(II) in mixed Cd-Zn system were 33% and 35% less than those in the single Cd(II)systems, while the adsorptive capacities to Zn(II) were 62% and 56% less than those in the single Zn(II) systems. The adsorptive capacities of loess to Cd(II) and Zn(II) in mixed Cd-Zn systems were 29% and 55% less than those in the single metal systems. The adsorptive capacities of loess-BCS500 (LBCS) and loess-BPM500 (LBPM) to Cd(II) in mixed Cd-Zn system were 40% and 38% less than those in the single Cd(II) systems, while the adsorptive capacities to Zn(II) were 63% and 60% less than those in the single Zn(II)systems. Moreover, the competitive adsorptive capacity of Cd(II) is greater than that of Zn(II). It can be seen that when heavy metal pollution with similar nature of multiple elements exists in soil, the amount of adsorbent should be increased to resist the possible weakened adsorption caused by competitive adsorption in order to guarantee an effective absorption treatment.
Afficher plus [+] Moins [-]Impact of Small Anaerobic Digester on Household Economy of Bangladeshi Livestock Farmers
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.
Afficher plus [+] Moins [-]Analysis of the Phytochemical Composition of Leaves of Six Superior Salt-Tolerant Mulberry Germplasm Grown Under Coastal Saline Soils of South 24 Parganas District of West Bengal, India
2024
Ritwik Acharya, Debnirmalya Gangopadhyay, S. Rehan Ahmad and Phalguni Bhattacharyya
The nutritive value of mulberry leaves makes it the only food of silkworms (Bombyx mori L.). It is recorded that 6.73 million hectares of area are affected by salinity and sodicity stresses covering various states of the country, which is becoming one of the major threats to popularizing sericulture in India. In the present study, chlorophyll, protein, catalase, peroxidase, and superoxide dismutase content of leaves of six mulberry germplasm viz., English Black, Kolitha-3, C776, Rotundiloba, BC259, and S1 grown under coastal saline soils of South 24 Parganas district of West Bengal, India was investigated. Results demonstrated a sharp decrease in the chlorophyll (2.35 to1.19 mg.g FW-1) and protein (30.10 to 15.20 mg.g FW-1) contents of leaves of all the mulberry germplasm with increasing soil salinity (1.60 to 22.70 dS.m-1). On the contrary, the number of stress-related antioxidant enzymes like catalase, peroxidases, and superoxide dismutase increased from 1.15 to 5.43, 1.43 to 4.76, and 8.65 to 25.15 g-1 FW.min-1, respectively. Overall, the field study indicated the superiority of Kolitha-3 and C776 grown in Canning (Canning I and II), Basanti, Namkhana, Kakdwip, and Sagar blocks of coastal regions of South 24 Parganas. The study deals with issues of the utilization of scarce land promoting income-generating avenues like sericulture in saline areas.
Afficher plus [+] Moins [-]Hunting Resource Management by Population Size Control by Remote Sensing Using an Unmanned Aerial Vehicle
2024
S. Ivanova and A. Prosekov
The study was carried out on the territory of the Kemerovo region-Kuzbass (Western Siberia, Russia). The purpose of the study was to obtain information on the species diversity and population of big-game animals. The monitoring was carried out on the forest territories of the region’s administrative districts. In the course of remote sensing using an unmanned aerial vehicle, the presence of all types of animals under consideration, except for the bear, was recorded. The deviation of the population number determined using the traditional method of digital technologies varied up to 50%. It was established that environmental measures organized and carried out by the regional administration and hunting farms improved the situation and stabilized the population of the main group of game animals. It was found that when using a sufficiently high sensitivity of the thermal imager (the used thermal imager had a very high sensitivity class ≤ 60 mK at 300 K), long-haired animals, which are characterized by a lower intensity of thermal radiation (for example, wolves) are identified and recognized in the images. The larger the animal and the worse the thermal insulation layer (wool or feathers), the easier it is to identify it in infrared images and the lower the sensitivity requirements of thermal imagers. The ability to recognize and record smaller animals and birds requires additional research on existing technologies. Our research has confirmed the validity of digital remote monitoring methods for managing the wildlife of hunting farms and nature conservation areas of the Siberian Taiga territories.
Afficher plus [+] Moins [-]The Suitability of Fe3O4/Graphene Oxide Nanocomposite for Adsorptive Removal of Methylene Blue and Congo Red
2024
Viet Cao, Phuong Anh Cao, Duy Linh Han, Minh Tuan Ngo, Truong Xuan Vuong and Hung Nguyen Manh
In this study, Fe3O4/GO nanocomposite was synthesized by hydrothermal method and tested for its efficiency in removing methylene blue (MB) and congo red (CR) from water. The synthesized nanocomposite was characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The optimal values for MB and CR removal were determined to be pH 6.0, an adsorbent weight of 50.0 mg, and a contact time of 10 min. The adsorption isotherms of the contaminants on the nanocomposite were analyzed using the Freundlich model, indicating a heterogeneous distribution of active sites on the adsorbent surface. The highest adsorption capacity of MB and CR is 135.1 and 285.7 mg.g-1, respectively. Moreover, Fe3O4/GO nanocomposite recycled five cycles with proper adsorption capacity. Overall, the Fe3O4/GO nanocomposite holds great promise for efficient and sustainable water treatment, providing safe and clean water globally.
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