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Power Recovery and Sulfate Removal from Rubber Wastewater with the Novel Model Multi-Electrode Microbial Fuel Cell
2021
Chaijak, Pimprapa | Sato, Chikashi
Microbial fuel cell (MFC) is a well-known technology that can convert contaminated substrate in the wastewater to electrical power. To gain more power output, the multi-electrode MFC was developed owing to it has a high surface area for anaerobic microbe adhesion. Here we show the multi-anode was made from the bamboo charcoal was combined with laccase-based cathode in the ceramic separator MFC for the rubber wastewater treatment and enhancing the power generation. The untreated rubber wastewater with initial COD and contaminated sulfate concentration of 3,500 mg/L and 1,100 mg/L was used as a anolyte. The 843.33±5.77 mA/m3 of CD, the 711.23±9.76 mW/m3 of PD were generated. Moreover, this system reached 83.07±3.01% of sulfate removal when it was operated at 30 °C for 12 hr. This study recommended that multi-anode with laccase based MFC can more successfully produce energy from untreated rubber wastewater. it will be greater in terms of electricity generation and sulfate removal.
Afficher plus [+] Moins [-]Identification and Characterization of Phenolic and Flavonoids Compounds Extracted from Tunisian Pomegranate Fruit Peel Exposed to Air Pollution: Gabes City, Tunisia
2021
Ben Amor, Afef | Ben Atia Zrouga, Khaoula | Chaira, Nizar | Ben Yahia, Leila | Nagaz, Kamel
The pomegranate (Punica granatum) fruit peel exposed to mixture air pollutants were collected from two sites with different air quality around the industrial area of Gabes city, Tunisia. The first site presented the ‘Polluted site’, which is situated in the oasis close to the industrial area. While, the second site referred to the ‘Control site’ located at 37 km from the industrial area. Using HPLC ES-MS, 21 phenols were identified and quantified in methanol extract from pomegranate fruit peel. The results showed that various phytochemical substances, including phenols acids and flavonoids, were identified and quantified in the peel extract. The polyphenols content and the flavonoids contents in peel obtained from polluted site were higher than that collected from the control site. The concentrations of the identified polyphenols were ranged between 0.39 and 7803.68 mg/ kg DW. The stimulation of some free phenolic compounds such syringic acid, transfrulic acid, epicatechin, rutin and quercetin was enregistred only in peel collected from contaminated environment. The quali-qualitative changes between sites are probably related to the difference in the air quality. The increase of polyphenols could be implicated during adaptive mechanisms under air pollution. Phenolic composition changes in Punica granatum peel could be also suggested as useful approach air pollution monitoring.
Afficher plus [+] Moins [-]Assessment of water quality of Oum Er Rabia River by Microbiological Quality Index and Water Quality Index
2021
Abba, El Hassan | Idrissi, Imam | Bennani, Younes | El Yaacoubi, Adnane | Cherroud, Sanae | Ainane, Tarik | Khaffou, Mhamed
Water resource management requires simple tools to enable managers to make decisions. This is the case for water quality indices that provide access to clear, synthetic and well-targeted information. In this study, we have chosen two indices based on two different approaches, the Microbiological Quality Index (MQI), which is determined from bacteriological analyses of water, and the Water Quality Index (WQI), which is based on physicochemical parameters. The Water Quality Index (WQI) shows a longitudinal upstream-downstream variation and ranges from is between five (5) (Null Faecal Contamination) at sampling point P1 and 3.4 (Moderate Fecal Contamination) at P2. The Water Quality Index (WQI) ranges from a low of 14.08 (excellent water quality) at the P1 level to a high of 93.05 at the P2 level (poor water quality) receiving wastewater discharges. The WQI results for P3 and P4, show that the water is of good quality (downstream of P2), which shows the degree of self-purification of the Oum Er Rabia River, regardless of the sampling period. Finally, the results of the MQI corroborate those obtained with the WQI for the water quality of the different sampling points.
Afficher plus [+] Moins [-]Electronic Waste in Bangladesh: Its Present Statutes, and Negative Impacts on Environment and Human Health
2021
Khuda, Kudrat-E
Technology has made the life of Bangladeshi people very flexible with new inventions. In most cases, here the people depend on these technological devices. These devices, along with various facilities, have also invited a series of problems mostly due to the lack of proper management. The Bangladeshi citizens often leave electronic devices that went bad or became unusable, in landfills, rivers, canals, and open spaces. As these devices possess a variety of toxic substances, dumping huge amounts of electronic waste can pollute the environment and threaten human health. Around 2.7 million metric tons of e-waste are generated each year in Bangladesh. Only 20-30% of this waste is recycled while the rest amount is released in landfills, rivers, canals, and open spaces posing a serious threat to the health and environment. Bangladesh has experienced rapid advancement in the technological sectors over the years. Therefore, it is a must to take steps necessary for avoiding the future jeopardized situation because of e-waste. The present e-waste management in Bangladesh experiences a number of drawbacks such as challenges in incentivization, unhygienic conditions of informal recycling, insufficient law and policy, less awareness, and lack of enthusiasm on part of the corporate to address the critical issues. In spite of the alarming levels of e-pollution in the country, the concerned authorities are yet to take any effective step or formulate any legislation to prevent the existing e-pollution. Moreover, the prevailing environmental laws are not adequate to address the issue and its application is still largely absent.
Afficher plus [+] Moins [-]Developing an Environmental-Friendly Trend of Thermal and Electrical Load Profiles in Ilam Industrial Town
2021
Taheri, Ramezan | Nasrabadi, Touraj | Yousefi, Hossein
Recently, making use of emerging fuels such as municipal waste has been proposed as an alternative for conventional fuels and also as a way for municipal waste disposal. This research, while modeling the thermal and electrical profiles of Ilam Industrial Town, examines the possibility of supplying the required fuel from municipal waste by the year 2041. For this purpose, different combined heat and power (CHP) scenarios were implemented in the LEAP software. According to the results, electricity generation will start gradually from the year of operation of the power plants in 2025 and reach more than 4.3 GWh in 2026. The production process will be incremental and is expected to reach 115.9, 119.1, 111.8, 118.4, 123.1, 118.9, 118.4, 118.4 GWh, respectively under the scenarios of gasifier CHP, CHP turbine incinerator, CHP steam incinerator, landfill CHP, syngas CHP, anaerobic digester CHP, combined gasifier and incinerator CHP, and ultimately improve to 118.9 GWh under the scenario of optimized gasifier and incinerator CHP. The required power plant capacity under the above-mentioned scenarios is expected to be approximately 21 MW by the year 2041and modify to 20.5 MW under the optimization scenario. The incinerator, combined-incinerator-and-gasifier, and optimization scenarios meet the supply and demand conditions of the generated waste, and in other scenarios, either the CHP supply share should be lower than 50% or the additional waste should be supplied from the nearby villages and towns.
Afficher plus [+] Moins [-]Human Health Risks Associated with Potentially Harmful Elements from Urban Soils of Hamedan City, Iran
2021
Tashakor, Mahsa | Modabberi, Soroush
Previous studies have shown that certain urban elements and arsenic are significantly concentrated in the surface soils of Hamedan, the largest city in western Iran. This study was carried out to assess the non-cancer and cancer risks from exposure to these potentially harmful elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) for Hamedan residence. In so doing, thirty-one urban and three background soil samples were analyzed by ICP-MS and the Risk Assessment Model established by the USEPA was applied to assess the health risk. It was found that the hazard index values for all the concerned elements are below 1, which indicates negligible to low non-carcinogenic risk for the exposed population. Nevertheless, some close to threshold values were recognized for As, Cr, and Pb implying that these elements have the potential to cause non-cancer risk for Hamedan citizens in case of long-term overexposure. The contribution of HQ-ingestion to total HI was the highest while the health effect associated with the inhalation exposure was trivial. Children were found to be more susceptible to potentially harmful elements than adults. The cancer risk calculation revealed that both children and adults are at increasing risk of developing cancer over a lifetime through ingestion, inhalation, and skin contact. All of the verified elements exceeded the tolerable level (1×10-6) of cancer risk however arsenic and chromium were found to be the most carcinogenic elements followed by Pb, Ni, and Cd. The carcinogenic risks were moderate for adults and high for children. This study indicates the necessity of designing effective strategies to reduce elemental pollution and to mitigate adverse human health effects of PHEs in Hamedan.
Afficher plus [+] Moins [-]Assessment of Variations and Correlation of Ozone and its Precursors, Benzene, Nitrogen Dioxide, Carbon monoxide and some Meteorological Variables at two Sites of Significant Spatial Variations in Delhi, Northern India
2021
Sharma, Ram Chhavi | Sharma, Niharika
Ozone(O3), and its precursors, Benzene (C6H6), Nitrogen Dioxide(NO2), Carbon Monoxide (CO) and meteorological parameters Temperature, Relative Humidity and Wind Speed were measured in urban air of two sites of significant spatial variations, Delhi Milk Scheme (DMS), Sadipur and Netaji Subhash Chander Institute of Technology(NSIT) Dwarka, during 2017–2018. Samples collected by Central Pollution Control Board (CPCB) has been analysed. The concentrations of Benzene, Nitrogen dioxide and Carbon monoxide were found to be more at DMS than NSIT site in winter season (11.137±3.258, 5.540±1.441, 55.333±12.741, 44.667±10.066μg/m3, 1.433±0.058, 1.033±0.287mg/m3 respectively) and summer season (3.167±1.222, 2.233±0.929, 50.333±2.082, 31.333±6.658μg/m3, 0.743±0.151, 0.443±0.051mg/m3 respectively) while Ozone was found to be more at NSIT than DMS site (40.333±3.215, 34.433±2.503μg/m3 respectively). The maximum concentrations of Benzene for the DMS and NSIT sites, respectively, were 32.4μg/m3 and 17.7μg/m3 and was observed in the month of November while minimum were 1.0μg/m3 and 0.6μg/m3 and was observed in the month of June. For Ozone, the maximum concentrations for the DMS and NSIT sites, respectively, were 100μg/m3 and 101μg/m3 and was observed in the month of June while minimum were 33.0μg/m3 and 28.0μg/m3 and was observed in the month of February and December respectively. Regression analyses were performed to correlate O3 concentrations with C6H6, NO2 and CO in order to infer their possible sources. The study reveals that there is significant correlation of O3 with C6H6 (r2=0.475) and CO (r2=0.985) in summer at DMS and with C6H6 (r2=0.902) & NO2(r2=0.728) in winter at NSIT. The correlation of O3, C6H6, NO2 and CO with Temperature, Relative Humidity and Wind Speed has also been investigated to understand their influence on these pollutants.
Afficher plus [+] Moins [-]Environmental Pollution and Disaggregated Economic Policy Uncertainty: Evidence from Japan
2021
Odugbesan, Jamiu Adetola | Aghazadeh, Sarah
Though, the attention of researchers on exploring the impact of economic policy uncertainty on carbon emissions is on increase, however, the impact of different types of economic policy uncertainty remains unexplored. Thus, this study investigates the impact of different types of economic policy uncertainty on carbon emissions in Japan. A monthly data from 1987M1 to 2019M12 was used, while the FMOLS, DOLS, CCR and ARDL estimators were employed for examining the cointegration among the variables, as well as the long- and short-run relationship between types of economic policy uncertainty and carbon emissions. The study findings revealed a long-run cointegration among energy consumption, per capita income, fiscal, exchange rate, monetary, and trade policy uncertainties and carbon emissions. Moreover, this study found energy consumption, exchange rate, monetary, and trade policy uncertainties to contribute significantly to the increase of carbon emissions in Japan. Finally, this study suggests that environmental policy makers in Japan should take into account the economic policy uncertainty so as to promote robust information for climate policy that will be targeted at ameliorating the carbon emissions in Japan.
Afficher plus [+] Moins [-]Treatment Oilfield Produced Water using Coagulation/Flocculation Process (case study: Alahdab Oilfield)
2021
Jabbar, Hussein Ali | Alatabe, Mohammed jaafar Ali
Produced water is a large amount of water wasted throughout the crude oil extraction process, it's a mixture of the well's deposition water and the water of oil wells extraction water. Produced water contains oil, suspended solids and dissolves solid. This study tested produced water collected from Alahdab oilfield/middle oil company for oil content and suspended solid contamination using chemical precipitation and coagulation-flocculation for reinjection and environmental considerations. Coagulation/flocculation is a common method used as primary purification to oily wastewater treatment due to its usability, performance, and low cost. Coagulant experimental was completed by A jar test device, additives of ferric sulfate and aluminium sulfate were in a range about (10 ـ 40) ppm, as well as polyelectrolyte- (polyacrylamide) as an additional flocculent in the range (1.5-3) ppm. The results show that ferric sulfate was more efficient at removing turbidity than aluminium sulfate under the same conditions, with the best removal of turbidity at dose concentration 30 ppm of Ferric sulfate and a flocculent dose concentration of 2.5 ppm of polyacrylamide, also with oil content decreasing from 396.71 ppm to 53.56 ppm.
Afficher plus [+] Moins [-]Improving Phytoremediation Efficiency of Copper-spiked Calcareous Soils by Humic Acid Applications
2021
Saffari, Vahid Reza | Saffari, Mahboub
In current study, the enhanced efficiency of copper (Cu) phytoremediation potential of Calendula officinalis L. was investigated in a Cu-spiked calcareous soil, using foliar and soil application of humic acid. For this purpose, in a greenhouse experiment, seedlings of C. officinalis were transferred to Cu-spiked soils (0, 250 and 500 mg/kg) and treated separately with soil (soil drench) and foliar (spraying plant leaves) humic acid applications at different levels (0, 10, 20 μM). The humic acid treatments were applied 2 weeks after transferring plant, and eventually the various biochemical-physiological traits and phytoremediation indices of Cu in C. officinalis were measured at (specific) time points. According to the results, C. officinalis grew normally without any toxicity signs in Cu-spiked soils, however with increasing the Cu levels, the dry weight biomass decreased and antioxidant enzymes activities increased. Both foliar and soil humic acid application in Cu-spiked soils increased dry weight biomass, photosynthetic pigment contents, Cu concentration, and bioconcentration factor (BCF). Furthermore, the application of this organic substance, obviously moderated the Cu stress since the antioxidant enzymes activities reduced compared to the control. Based on the results, the obtained translocation factor (TF) and BCF values of Cu, which were >1, indicated that this plant is a Cu-hyperaccumulator, which could extract Cu via phytoextraction mechanism. Generally, the results of this study showed that, among the humic acid treatments, application of 20 μM (especially soil drench application) had the best effect on increasing Cu phytoremediation efficiency in the studied soil and it recommended to enhance the efficiency of Cu phytoremediation in calcareous soils.
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