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Exposure and size distribution of nitrated and oxygenated polycyclic aromatic hydrocarbons among the population using different household fuels
2016
Shen, Guofeng | Chen, Yuanchen | Du, Wei | Lin, Nan | Wang, Xilong | Cheng, Hefa | Liu, Junfeng | Xue, Chunyu | Liu, Guangqing | Zeng, E. Y. (Eddy Y.) | Xing, Baoshan | Tao, Shu
Polycyclic aromatic hydrocarbons (PAHs) derivatives like nitrated and oxygenated PAHs are of growing concerns because of considerably higher toxicity and important roles during atmospheric chemical reactions. Residential solid fuel combustion is likely to be one large primary source of these pollutants in developing countries. In this study, inhalation exposure to nitrated and oxygenated PAH derivatives was evaluated among rural residents using carried samplers. The exposure levels of individual nitrated PAHs ranged from 4.04 (9-nitrated phenanthrene) to 89.8 (9-nitrated anthracene) pg/m3, and of oxy-PAHs were 0.570 (benzo[a]anthracene-7, 12-dione) to 7.99 (Benzanthrone) ng/m3, generally higher in wood user than that in anthracite user. A majority of derivatives in particle presented in PM2.5 (80% for nitrated naphthalene and over 90% for other targets) and even fine PM1.0. Mass fractions of PAH derivatives in fine and ultra-fine particles were significantly higher than the fractions of corresponding parent PAHs, indicating more adverse health outcomes induced by these derivatives. The inhalation exposure levels for residents adopting wood gasifier burners was significantly lower than the documented results for those burning wood in typical built-in brick stoves, and comparable to those using LPG and electricity, which provided vital information for clean stove development and intervention programs.
Mostrar más [+] Menos [-]Changes in quality of life and perceptions of general health before and after operation of wind turbines
2016
Jalali, Leila | Bigelow, Philip | McColl, Stephen | Majowicz, Shannon | Gohari, Mahmood | Waterhouse, Ryan
Ontario is Canada’s provincial leader in wind energy, with over 4000 MW of installed capacity supplying approximately five percent of the province’s electricity demand. Wind energy is now one of the fastest-growing sources of renewable power in Canada and many other countries. However, its possible negative impact on population health, as a new source of environmental noise, has raised concerns for people living in proximity to wind turbines (WTs). The aims of this study were to assess the effect of individual differences and annoyance on the self-reported general health and health-related quality of life (QOL) of nearby residents, using a pre- and post-exposure design. Prospective cohort data were collected before and after WT operations, from the individuals (n = 43) in Ontario, Canada. General health and QOL metrics were measured using standard scales, such as SF12, life satisfaction scales developed by Diener (SWLS) and the Canadian Community Health Survey (CCHS-SWL). The mean values for the Mental Component Score of SF12 (p = 0.002), SWLS (p < 0.001), and CCHS-SWL (p = 0.044) significantly worsened after WT operation for those participants who had a negative attitude to WTs, who voiced concerns about property devaluation, and/or who reported being visually or noise annoyed.
Mostrar más [+] Menos [-]The emission abatement policy paradox in Australia: evidence from energy-emission nexus
2016
This paper attempts to investigate the emissions embodied in Australia’s economic growth and disaggregate primary energy sources used for electricity production. Using time series data over the period of 1990–2012, the ARDL bounds test approach to cointegration technique is applied to test the long-run association among the underlying variables. The regression results validate the long-run equilibrium relationship among all vectors and confirm that CO₂ emissions, economic growth, and disaggregate primary energy consumption impact each other in the long-run path. Afterwards, the long- and short-run analyses are conducted using error correction model. The results show that economic growth, coal, oil, gas, and hydro energy sources have positive and statistically significant impact on CO₂ emissions both in long and short run, with an exception of renewables which has negative impact only in the long run. The results conclude that Australia faces wide gap between emission abatement policies and targets. The country still relies on emission intensive fossil fuels (i.e., coal and oil) to meet the indigenous electricity demand.
Mostrar más [+] Menos [-]Phenol Degradation by Suspended Biomass in Aerobic/Anaerobic Electrochemical Reactor
2016
Ailijiang, Nuerla | Chang, Jiali | Wu, Qing | Li, Peng | Liang, Peng | Zhang, Xiaoyuan | Huang, Xia
The effect of direct current (DC) on phenol biodegradation under aerobic/anaerobic condition was investigated in this study using a bioelectrochemical reactor. It was found that phenol biodegradation was inhibited with current ranged from 10 to 40 mA. The growth of biomass was reduced to 43.2 ± 6.6 % for aerobic sludge and 38.6 ± 7.3 % for anaerobic sludge, but the loosely bound extracellular polymer substances (LB–EPS) were increased 91.2 ± 1.3 % for aerobic sludge and 62.8 ± 0.8 % for anaerobic sludge as the current increased from 10 to 40 mA. Adenosine triphosphate (ATP) content of aerobic sludge was also reduced 0.481 ± 0.04-fold and 0.512 ± 0.05-fold lower and 1.34 ± 0.13-fold higher than that of the control when the current was increased from 10 to 40 mA. The results of phosphate buffer saline adding treatment indicated that lower pH caused by a DC above 10 mA was responsible for the reduced phenol biodegradation, leading to the reduction of biomass. However, lower intensity of current (5 mA) had no significant impact on phenol degradation rate, pH, LB–EPS, ATP content, and cell growth of aerobic/anaerobic sludge. These results give us a more detailed understanding of the effects of electricity on the treatment of phenol containing wastewater.
Mostrar más [+] Menos [-]Influence of supporting electrolyte in electricity generation and degradation of organic pollutants in photocatalytic fuel cell
2016
Khalik, Wan Fadhilah | Ong, Soon-An | Ho, Li-Ngee | Wong, Yee-Shian | Voon, Chun-Hong | Yusuf, Sara Yasina | Yusoff, Nik Athirah | Lee, Sin-Li
This study investigated the effect of different supporting electrolyte (Na₂SO₄, MgSO₄, NaCl) in degradation of Reactive Black 5 (RB5) and generation of electricity. Zinc oxide (ZnO) was immobilized onto carbon felt acted as photoanode, while Pt-coated carbon paper as photocathode was placed in a single chamber photocatalytic fuel cell, which then irradiated by UV lamp for 24 h. The degradation and mineralization of RB5 with 0.1 M NaCl rapidly decreased after 24-h irradiation time, followed by MgSO₄, Na₂SO₄ and without electrolyte. The voltage outputs for Na₂SO₄, MgSO₄ and NaCl were 908, 628 and 523 mV, respectively, after 24-h irradiation time; meanwhile, their short-circuit current density, J SC, was 1.3, 1.2 and 1.05 mA cm⁻², respectively. The power densities for Na₂SO₄, MgSO₄ and NaCl were 0.335, 0.256 and 0.245 mW cm⁻², respectively. On the other hand, for without supporting electrolyte, the voltage output and short-circuit current density was 271.6 mV and 0.055 mA cm⁻², respectively. The supporting electrolyte NaCl showed greater performance in degradation of RB5 and generation of electricity due to the formation of superoxide radical anions which enhance the degradation of dye. The mineralization of RB5 with different supporting electrolyte was measured through spectrum analysis and reduction in COD concentration.
Mostrar más [+] Menos [-]Characterization and source identification of trace elements in airborne particulates at urban and suburban atmospheres of Tabriz, Iran
2016
Gholampour, Akbar | Nabizadeh, Ramin | Hassanvand, Mohammad Sadegh | Taghipour, Hasan | Rafee, Mohammad | Alizadeh, Zahra | Faridi, Sasan | Mahvi, Amir Hossein
Concentration of particulate matter (PM₁₀ and total suspended particulate (TSP)) and their elemental constituents were measured to identify the major sources of elements in urban and industrial suburban sites in Tabriz, Iran, from September 2012 to June 2013. TSP and PM₁₀ samples were collected using high-volume samplers. Concentrations of 31 elements in aerosols and crustal soil were determined by ICPMS. The most abundant detected metals in the urban sampling sites were Al (217.5–4019.9 ng m⁻³), Fe (272.5–7658.0 ng m⁻³), Pt (4.7–1994.4 ng m⁻³), and P (13.6–2054.8 ng m⁻³(for TSP and Al (217.6–3687.3 ng m⁻³), Fe (197.1–3724.9 ng m⁻³), Pt (65.9–2054.5 ng m⁻³), and P (11.0–756.6 ng m⁻³(for PM₁₀. In the suburban sampling site, the most abundant detected metals were Al (2083.0–9664.0 ng m⁻³), Fe (360.0–7221.5 ng m⁻³), P (229.4–870.5 ng m⁻³), and Ti (137.3–849.7 ng m⁻³) for TSP and Al (218.5–4179.6 ng m⁻³), Fe (106.3–2005.1 ng m⁻³), P (251.9–908.4 ng m⁻³), and Ba (10.6–584.9 ng m⁻³) for PM₁₀. For the crustal soil, the most abundant detected elements included Al (60,088–60,694 ppm), Fe (19,886–20,474 ppm), Ti (894–3481 ppm), and Si (365–4246 ppm). Key emission sources were identified, and the concentrations contributed from individual sources were estimated. Enrichment factor (EF) explaining a preponderance of the variance in the data was applied to the datasets. EF calculations revealed that non-crustal trace elements were more enriched in the urban than suburban sampling sites. Results of the factor analysis on the elements showed that emissions from road traffic (involving oil and fuel combustions by vehicles, platinum group elements from vehicle exhaust, and resuspension of particulate matter from polluted soil) and construction dust from nearby construction sites and electricity generation plant were the major contributors of anthropogenic metals at ambient atmosphere in Tabriz. Results of this study elucidated the need for developing pollution control strategy, especially vehicle exhaust control, and creating green spaces around the city.
Mostrar más [+] Menos [-]Food waste collection and recycling for value-added products: potential applications and challenges in Hong Kong
2016
Lo, Irene M. C. | Woon, Kok Sin
About 3600 tonnes food waste are discarded in the landfills in Hong Kong daily. It is expected that the three strategic landfills in Hong Kong will be exhausted by 2020. In consideration of the food waste management environment and community needs in Hong Kong, as well as with reference to the food waste management systems in cities such as Linköping in Sweden and Oslo in Norway, a framework of food waste separation, collection, and recycling for food waste valorization is proposed in this paper. Food waste can be packed in an optic bag (i.e., a bag in green color), while the residual municipal solid waste (MSW) can be packed in a common plastic bag. All the wastes are then sent to the refuse transfer stations, in which food waste is separated from the residual MSW using an optic sensor. On the one hand, the sorted food waste can be converted into valuable materials (e.g., compost, swine feed, fish feed). On the other hand, the sorted food waste can be sent to the proposed Organic Waste Treatment Facilities and sewage treatment works for producing biogas. The biogas can be recovered to produce electricity and city gas (i.e., heating fuel for cooking purpose). Due to the challenges faced by the value-added products in Hong Kong, the biogas is recommended to be upgraded as a biogas fuel for vehicle use. Hopefully, the proposed framework will provide a simple and effective approach to food waste separation at source and promote sustainable use of waste to resource in Hong Kong.
Mostrar más [+] Menos [-]Comparison greenhouse gas (GHG) emissions and global warming potential (GWP) effect of energy use in different wheat agroecosystems in Iran
2016
Yousefi, Mohammad | Mahdavi Damghani, Abdolmajid | Khoramivafa, Mahmud
The aims of this study were to determine energy requirement and global warming potential (GWP) in low and high input wheat production systems in western of Iran. For this purpose, data were collected from 120 wheat farms applying questionnaires via face-to-face interviews. Results showed that total energy input and output were 60,000 and 180,000 MJ ha⁻¹ in high input systems and 14,000 and 56,000 MJ ha⁻¹ in low input wheat production systems, respectively. The highest share of total input energy in high input systems recorded for electricity power, N fertilizer, and diesel fuel with 36, 18, and 13 %, respectively, while the highest share of input energy in low input systems observed for N fertilizer, diesel fuel, and seed with 32, 31, and 27 %. Energy use efficiency in high input systems (3.03) was lower than of low input systems (3.94). Total CO₂, N₂O, and CH₄ emissions in high input systems were 1981.25, 31.18, and 1.87 kg ha⁻¹, respectively. These amounts were 699.88, 0.02, and 0.96 kg ha⁻¹ in low input systems. In high input wheat production systems, total GWP was 11686.63 kg CO₂eq ha⁻¹ wheat. This amount was 725.89 kg CO₂eq ha⁻¹ in low input systems. The results show that 1 ha of high input system will produce greenhouse effect 17 times of low input systems. So, high input production systems need to have an efficient and sustainable management for reducing environmental crises such as change climate.
Mostrar más [+] Menos [-]The German R&D Program for CO2 Utilization—Innovations for a Green Economy
2016
Mennicken, Lothar | Janz, Alexander | Roth, Stefanie
Carbon capture and utilization (CCU) is a field of key emerging technologies. CCU can support the economy to decrease the dependency on fossil carbon raw materials, to stabilize electricity grids and markets with respect to a growing share of fluctuating renewable energy. Furthermore, it can contribute to mitigate anthropogenic CO₂ emissions. The German Federal Ministry of Education and Research has provided substantial financial support for research and development projects, stimulating research, development, and innovations in the field of CO₂ utilization. This review provides an overview over the most relevant funding measures in this field. Examples of successful projects demonstrate that CCU technologies are already economically viable or technologically ready for industrial application. CCU technologies as elements of a future “green economy” can contribute to reach the ambitious German sustainability targets with regard to climate protection as well as raw material productivity.
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