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Evaluation of the Energy Factor and Equivalent CO2 Gas Emission by Utilization of Industrial By-products in Concrete for Environmental Protection Full text
2023
B. Saravanan, R. Divahar, S. P. Sangeetha and M. Bhuvaneshwari
Climate change and global warming are two of the world’s most pressing environmental issues. With CO2 being one of the most significant greenhouse gases released into the atmosphere, and cement and concrete manufacturing accounting for roughly 10% of worldwide CO2 emissions, the construction sector must employ an environmentally sustainable substance as a substitute for cement. The CO2 emissions, energy factor, and strength qualities of concrete were investigated. Those negative reaction of conventional cementitious substances is reduced by the development of binary and ternary cementitious systems. In this study, two mineral admixtures obtained from industrial waste substances, red mud (RM) and silica fume (SF), had been used as the alternatives for cement and fine aggregate was fully replaced by manufactured sand (M-sand). An experimental examination of the compressive strength, water absorption, density of concrete, equivalent CO2 emission, and energy factor for environmental benefits with the comparison of RM on SF-based eco-friendly concrete mix of M30 grade was used. A binary and ternary blended cementitious system with RM and SM was created with twelve various mix proportions, varying from 0-20% by 5% increases. From the binary blended cementitious system (BBS), based on the observed mechanical characteristic of concrete it was found that the optimum level of RM was 15% and SF was 10 % by the volume of cement. Similarly, for the ternary blended cementitious system (TBS), the level of 10% RM and 10% SF in the cement mixture provides a much higher improvement in compression strength compared to the alternative trials. The negative sign implies that replacing cement with RM and SF reduces energy consumption (-1.91% to -6.97%) and CO2 emissions (-4.52% to -16.16%). The use of mineral admixtures such as RM and SM in supplementary cementitious materials results in a significant outcome and potential impact on the production of sustainable concrete that addresses environmental issues.
Show more [+] Less [-]Evapotranspiration Over the Indian Region: Implications of Climate Change and Land Use/Land Cover Change Full text
2023
Garima Singh and Sudhir Kumar Singh
Evapotranspiration (ET) plays a significant role in climatic studies, directly influencing the hydrological cycle, energy balance equation, and surface vegetation. ET comprises three components: bare soil or ground evaporation, evaporation, and transpiration, in which vegetation removes water influenced by food grain production. In turn, soil moisture availability depends on precipitation characteristics over land, surface net radiation, and wind speed are the major climatic factors that together determine the magnitude of ET. This controls moisture availability in the lower troposphere, hence atmospheric stability, chances of cloud formation, and precipitation. Though the study of evapotranspiration is important for determining agricultural water consumption and analyzing drought situations, there is a lot of uncertainty in its accurate estimation. Land use/Land cover changes (LULCC) occurring throughout the Indian subcontinent have been found to affect the characteristics of low to moderate rainfall events and surface temperature extremes (Halder et al. 2016). A global warming scenario will change the hydrological cycle, and the impact of anthropogenic factors has also necessitated the need to understand the mechanisms that control changes in ET over India. In this study, we want to analyze the relationship between transpiration and the Normalized Difference Vegetation Index (NDVI) and investigate the relationship between canopy interception with respect to NDVI all over the Indian region. Attempts have been made to assess the impact of changes in climate and LULC on ET and its three components over the Indian region from 1981 till the present time. The monsoon season increases precipitation, and soil evaporation is found to increase at first, along with an increase in NDVI followed by canopy evaporation and transpiration. It is noted that changes in precipitation and LULCC across the Indian subcontinent have contributed significantly to changes in ET in different seasons. As variability in surface net radiation also plays an important role in controlling changes in total ET, it is being investigated.
Show more [+] Less [-]Assessment of Particulate and Gaseous Fluoride in Phosphate Fertilizer Industry Full text
2023
S. Jawahar, K. Shridhar, V. Dhananjayan, K. Panjakumar, B. Ravichandran, A. Ravinder Nath and Nirmala Babu Rao
Fluorides are emitted in both gaseous and particle forms in the industrial sector. However, studies usually only report total fluoride content. Therefore, the study aimed to assess the particulate, gaseous fluoride and correlate it with the respirable dust particles in Single Super Phosphate (SSP), Granular Single Super Phosphate (GSSP), and administration divisions of the industry. Respirable dust particles, particulate fluoride, and hydrogen fluoride in the work environment were collected on a filter cassette containing an MCE filter paper (0.8 micron 37-mm) and Na2CO3 impregnated backup pad, respectively, using a personal sampler. The fluoride samples were analyzed using Ion Selective Electrode (ISE) and expressed as milligrams per meter cube (mg.m-3). The respirable dust, particulate, and gaseous fluoride content were found to have statistically significant differences (p<0.001) between the divisions (SSP, GSSP, and administration) in the static monitoring, whereas, in the case of personal monitoring, no significant differences were observed. Average airborne respirable, particulate, and gaseous fluoride levels in static monitoring were 1.37, 1.03, 0.20 mg.m-3, 0.018, 0.008, 0.001 mg.m-3, and 0.808, 0.403, 0.026 ppm in SSP, GSSP and administration respectively, whereas in personal monitoring the average respirable, particulate and gaseous fluoride concentrations were 1.18, 0.85, 0.30 mg.m-3, 0.0013, 0.007, 0.002 mg.m-3 and 0.356, 0.258, 0.011 ppm in SSP, GSSP and administration respectively. The present study observed that the levels of fluoride decreased with an increase in distance from SSP, followed by GSSP and administration. It indicates that the fluoride exposure was inversely proportional to the distance of the source. This study outcome will help to design a policy and intervention to mitigate fluoride exposure among workers.
Show more [+] Less [-]Impact of Nanoplastics on Marine Life: A Review Full text
2023
S. Das
Minute plastic subdivisions like microplastics and nanoplastics have recently gained considerable attention because of their toxic effects on the environment and human health. Many plastics have been consumed worldwide regularly, and most are thrown away after a single use. They all end up in the sea and ocean, leading to a large debris of plastic garbage in the marine environment. Different physical and chemical processes occur in the marine ecosystem to degrade the macroplastics into micro- and nano-level plastics. Owing to their small size and large surface area, nanoplastics can easily be ingested into the tissues and organs of various marine species (both vertebrates and invertebrates) and accumulate more toxic materials in them than micro and macroplastics. Several reports have been obtained on the toxicity of plastics and microplastics on marine organisms. Still, till now, a cursory report has been found on the potential risk of nanoplastics in connection with marine life. This review highlights the origins of nanoplastics (NPs), their properties, characterization, and impact on marine ecosystems, along with their remediation and future aspects. The review will also untangle and specify the area of nanoplastics on which further research is urgently needed to better understand its toxic effect and eco-friendly restoration on the environment, especially on marine life.
Show more [+] Less [-]Heavy Metal Remediation from Water/Wastewater Using Bioadsorbents - A Review Full text
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.
Show more [+] Less [-]Effect of Fulvic Acid on the Denitrification in Deep Subsurface Wastewater Infiltration System Full text
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.
Show more [+] Less [-]Emerging Trends in Wastewater Treatment of Semiconductor Industry: A Review Full text
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.
Show more [+] Less [-]Ambient Air Quality Monitoring with Reference to Particulate Matter (PM10) in Kolhapur City Full text
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.
Show more [+] Less [-]Household Energy Fuel Choice in Nigeria Residential Urban Area Full text
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.
Show more [+] Less [-]Biodiesel from Dunaliella salina Microalgae Using Base Catalyzed Transesterification – An Assessment through GC/MS, FTIR and NMR Studies Full text
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.
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