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Heavy Metal Remediation from Water/Wastewater Using Bioadsorbents - A Review Полный текст
2023
Akhil Tewari, Dinesh S. Bhutada and Vinayak Wadgaonkar
This paper aims to emphasize heavy metals’ impact on water and its removal mechanism with a focus on adsorption. Furthermore, factors affecting bio adsorption, such as temperature, pH, RPM, and initial heavy metal concentration, have been studied for different heavy metals and bioadsorbents. A comparison of their adsorption capacities and efficiencies has been made. This review reviewed different bioadsorbents for their suitability in removing cadmium, lead, and copper ions from water and wastewater, typically by using adsorption as a methodology. A suitable summary compares various heavy metal removal techniques and their advantages and limitations. For adsorption, the characteristics of bioadsorbents and their activation steps have been consolidated. Furthermore, the effects of operational parameters and adsorption mechanisms have been discussed in the review. Apart from assessing the suitability of bioadsorbent, a novel bioadsorbent has been suggested for copper ions removal. The findings shall be significantly useful in applying bioadsorbent in water/wastewater treatment fields to reduce heavy metal pollution. Thorough and well-planned research in this field can facilitate the creation of sustainable and durable technology for wastewater treatment, addressing the increasing demand for safe and dependable water resources, focusing on making it cost-effective and recyclable.
Показать больше [+] Меньше [-]Effect of Fulvic Acid on the Denitrification in Deep Subsurface Wastewater Infiltration System Полный текст
2023
Jingjing Lv, Jingjing Li, Yanyan Dou, Guoke Chen, Yubing Ye and Li’an Hou
This work aims to explore the impact of fulvic acid (FA) on denitrification within the purification process of sewage in the deep subsurface wastewater infiltration system (DSWIS). In the system, an organic glass column (height = 2.40 m; radius = 0.30 m) was filled with several layers of soil. Simulated domestic wastewater and extracted FA from landfill leachate were used in the experiments. It was found that before and after the addition of FA, COD, and NH4+-N were efficiently removed when a hydraulic load was 8 cm·d-1. Moreover, after FA addition, the removal efficiency of TN was enhanced from 67.74% to 78.01%. Organic matter transformation analysis indicated that in the under part, the shortage of carbon sources limited the denitrification prior to FA addition, resulting in a low TN removal efficiency. However, after adding FA, more FA-like substances were transferred into protein-like matters than before the addition of FA, which has helped produce more easily biodegradable organics for denitrification. So, the addition of FA could enhance the denitrification process in the system of DSWIS.
Показать больше [+] Меньше [-]Emerging Trends in Wastewater Treatment of Semiconductor Industry: A Review Полный текст
2023
Hemant S. Sadafale and R.W. Gaikwad
The semiconductor industry produces a lot of wastewater. These wastewaters can affect the environment if they are not treated. As a result, one of the semiconductor industry’s primary concerns and duties is the treatment and disposal of wastewater from the industry. Many processes, including electrocoagulation, electro-adsorption, and coagulation-flocculation using both natural and synthetic coagulants, have been invented over the years for purifying semiconductor effluent. The long-term viability of this system is unknown although it generates solid by-products (sludge) and requires routine sludge disposal, both of which raise the operational expenses of effluent treatment. Thus, a sustainable alternative method of removing contaminants from the semiconductor industry is needed to advance toward pollution prevention and green innovation. The hydrodynamic cavitation technique has improved over time and is useful for treating water and wastewater. This article gives an insight into different wastewater technologies, so proper technology must be chosen.
Показать больше [+] Меньше [-]Ambient Air Quality Monitoring with Reference to Particulate Matter (PM10) in Kolhapur City Полный текст
2023
C. S. Bhosale, P. R. Mane, J. S. Salunkhe, V. M. Mothgare, S. S. Sutar, S. B. Manglekar, A. S. Jadhav and P. D. Raut
Air is an important medium for all living beings and is essential for the well-being of all. Monitoring of air is important to know the quality of air. The air quality monitoring was carried out in Kolhapur City under the National Air Monitoring Program. The present study involves the assessment of PM10 as described in the National Ambient Air Quality Standards (NAAQS). The source apportionment study related to particulate matter was carried out in Kolhapur City. The study also determined the average PM10 concentration in the city as it will be useful for preparing an action plan to reduce PM10 concentration. PM10 concentration was calculated as per the standard method adopted by CPCB. Sampling was carried out for 8 hours in three shifts twice a week at each sampling site for three consecutive years. Mahadwar Road (MR) and Dabholkar Corner (DC) were selected per the surrounding residential area, population density, and traffic conjunction. The third site Shivaji University (SUK), was selected as a control site. The results indicated that the PM10 level has risen above the prescribed standards of NAAQS. The reason for the rise in PM10 may be due to fossil fuel burning, construction activity, vehicles, and unpaved roads. The Analysis of Variance (ANOVA) technique is used to check the equality of the mean concentration of PM10 at these three locations and found a significant difference between mean concentrations of PM10, suggesting increased particulate matter.
Показать больше [+] Меньше [-]Household Energy Fuel Choice in Nigeria Residential Urban Area Полный текст
2023
O. J. Ubani, A. Okosun, G. Chukwurah and Ivo Henry
In most Nigerian cities, there have been an increased number of trading in charcoals, firewood, and sawdust. Yet, the fast citing of cooking gas refilling stations in these areas requires much to be studied since their increasing number suggests great demand for cooking gas. The knowledge of the different household fuel choices and the drivers of this choice was lacking in Nigerian cities, thus the inability of energy policymakers to predict and plan household fuel agenda in Nigeria. The thrust of this paper was to analyze the household energy fuel choice and the pattern of consumption as well as analyze the household socioeconomic factors that influenced the fuel choice in the Abakaliki urban area of Ebonyi State, Nigeria. Stratified and simple random sampling was adopted in the study. Regression was used to consider the relationship between energy fuel choice and household socioeconomic factors. It was revealed that there was a mixture of traditional and modern energy fuel choices in the study area, with the modern energy fuel choices (gas and electricity) having higher patronage. There was a significant relationship between energy fuel choice and household socioeconomic factors. It was recommended, among others, that a clear energy fuel policy that will adopt the identified explorable household socioeconomic factors that influence the choice of energy fuel be developed.
Показать больше [+] Меньше [-]Biodiesel from Dunaliella salina Microalgae Using Base Catalyzed Transesterification – An Assessment through GC/MS, FTIR and NMR Studies Полный текст
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 [-]Risk Perception of Healthcare Workers Regarding Polymer Medical Waste Management Полный текст
2023
Jasneet Kaur, Sheela Upendra and Shital Barde
Despite the relatively small amounts produced, medical waste is a significant issue for the government and the healthcare industry primarily because it poses threats to persons and the environment. Healthcare wastes pose threats to the environment and public health, but knowledge of these concerns and how they relate to management techniques is still lacking. Evaluating waste management practices and healthcare staff expertise is critical to identify shortcomings and lower risk levels. The study was conducted at three selected private hospitals. These three hospitals contain 462 beds, all together with 184 healthcare workers. The study was designed as a descriptive cross-sectional study, and three private healthcare institutions in the study region were evaluated. These 100 healthcare workers were chosen by purposive sampling. The hospitals under consideration include general surgical, Gynecological, pediatric, and various specialty treatments. Data was gathered for the study utilizing a quantitative questionnaire, which includes closed-ended structured questionnaires. The results showed that most healthcare workers practice waste segregation at source. Chemical cross-linking was very poor. However, waste shredding technology is being used substantially. Risk perception among Healthcare workers regarding polymer help waste management showed more of average to high risk. The study concluded that despite the existence of policies and plans, execution is still subpar at private healthcare institutions. The creation of guidelines for hospital waste management, their distribution to other institutions, and their encouragement to do a critical self-evaluation should all be required by the government.
Показать больше [+] Меньше [-]Palladium-Based Catalytic Treatment and a Rhizobacterial-Assisted Detoxification for the Enhanced Removal of Lindane Полный текст
2023
Rachana Sharma and Prabhu Thangadurai
This study aimed to assess the efficacy of a bimetallic system consisting of Mg0-Pd0 and the bacterium Acinetobacter sp. for the complete detoxification of lindane. Our results demonstrate that palladium immobilized on activated charcoal achieved a removal rate of >99% for 100 mg.L-1 of Lindane within 10 minutes, with the accumulation of trace amounts of intermediates. The reductive transformation of lindane followed 1st-order kinetics, with a calculated rate constant (kobs) of 0.77 min-1. The bimetallic system resulted in the formation of a non-toxic hydrocarbon as the end-product, indicating complete dehalogenation of lindane. Furthermore, Acinetobacter sp. effectively mineralized >98% of 100 mg.L-1 of Lindane after 26 h of cultivation without any accumulation of toxic metabolite(s) in the reaction medium, demonstrating the efficiency of the biological system. Integrating both chemical and biological systems could provide significant advantages for the treatment of lindane, reducing the treatment time and overall cost. This synergistic approach can significantly enhance the overall removal efficiency of lindane from contaminated soil and water.
Показать больше [+] Меньше [-]Predictability Augmentation by In-silico Study to In-vivo and In-vitro Results of Lung Doses of Airborne Fine and Ultrafine Particles Inhaled by Humans at Industrial Workplaces Полный текст
2023
M. Ali
This study correlates computational predictions with in vivo and in vitro experimental results of inhaled fine and ultrafine particulate matter (PM) transport, dissemination, and deposition in the human respiratory airways. Epidemiological studies suggest that workplace exposure to anthropogenic pollutant PMs is a risk factor for increased susceptibility to acute broncho-pulmonary illnesses. However, investigations on detailed human inhalation and PM transport processes are restrictive from time, cost, and ethical perspectives. Computational simulation based on the Multiple Path Particle Dosimetry (MPPD) model was employed to quantify the risks associated with workplace exposure of these PMs. Here, the physical, mechanical, and electrical properties of PMs of carbon black (CB) and ultrafine particles (UFPs) from wire-cut electrical discharge machining (WEDM), with mass median aerodynamic diameter (CMAD) in the range of 1 nm to 1000 nm, were used as input parameters of MPPD. Additionally, it mimicked occupational workers’ age, body mass index, and oronasal-combinational nose and mouth breathing exposure time. The deposition results were compared with several vivo and in vitro experimental data reported in the literature, and satisfactory agreements were found. For example, a total lung dose of CB-PMs of 100 nm is the highest (28%), while a 380 nm dose is the lowest (15%). Afterward, deposition increases with particle size, reaching 26% for 1000 nm. In the case of WEDM-UFPs, about 98% of all 1.0 nm inhaled particles remain in the lung. Subsequently, the deposition dose decreases with the particle size and reaches up to 28% for 100 nm particles. Approximately 51% of deposited WEDM-UFPs are of CMAD ≤ 5 nm. The images of lung geometry also observed the maximum deposited mass and mass flux rate in the head, tracheobronchial, and pulmonary airways.
Показать больше [+] Меньше [-]The Role of Stakeholders in Achieving Sustainable Agriculture: A Case Study in Sragen Regency, Indonesia Полный текст
2023
R. C. Sartika, Y. Purwaningsih, E. Gravitiani and P. Nitiyasa
Rice farming plays a crucial role in maintaining national resilience and stability. However, its sustainability is faced with complex and multidimensional challenges. One of the challenges agricultural sustainability faces is the reduction of farmland due to the construction of toll roads. The development of the Solo-Mantingan-Ngawi toll road has significantly impacted the reduction of agricultural land in Sragen Regency, the second-largest rice-producing area in Central Java after Grobogan. This issue will threaten national food security if left unaddressed without further intervention. The development of sustainable agriculture is expected to be a solution to promoting food resilience. However, stakeholder involvement is necessary for successful development. This research aims to identify the stakeholders involved in developing sustainable agriculture to promote food resilience in Sragen Regency. This study adopts a mixed-method approach with data collection through in-depth interviews. The analytical tool used in this research is MACTOR (Matrix of Alliance and Conflict: Tactic, Objectives, and Recommendation). The study identified the stakeholders influencing the development of sustainable agriculture in Sragen Regency as Farmer Groups, Farmers, Village Heads, Agriculture Extenders, and the Department of Agriculture and Food Security. These findings serve as a basis for developing collaborative patterns among all stakeholders required to develop sustainable agriculture to achieve food resilience in the Sragen Regency.
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