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1.
Epidemiol Prev ; 45(3): 155-163, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34212696

RESUMO

BACKGROUND: the exposure to a coal-fired power plant has been shown to increase mortality both for cardiovascular and respiratory causes among an exposed cohort in comparison with a cohort of unexposed. Hazard ratios between 1.30 and 1.90 were found for cardiovascular and respiratory mortality. OBJECTIVES: to estimate the individual life shortening among the exposed due to power plant emissions. DESIGN: survival for cardiovascular and respiratory disease in the exposed vs unexposed groups was estimated by the Kaplan-Meier method. For each gender and exposure, a fictitious cohort with a cumulative 30-year follow up was built combining three subcohorts of age at entry of 55-64, 65-74, and 75-84 years, with 10 years of follow up each. Survivals at 10 years in the 55-64-year subcohort were used as initial risks for 65-74-year subcohort; then, survivals at 10 years of the 65-74-year subcohort were used as initial risk in the 75-84-year subcohort. Eventually, 30-years cumulative follow up cohorts were obtained by gender and exposure. Individual life-shortening in people exposed was estimated as time from death of an exposed subject to the subsequent time when the unexposed cohort reached the same risk of the exposed subject at that time of the death. Here, it is proposed a method to take into account causes other than those considered. SETTING AND PARTICIPANTS: 144,018 subjects aged 55-74 years at entry of both genders belonging to the open cohort of residents of 12 municipalities (including Savona) from 2001 to 2013 in the area where the coal-fired power plant of Vado-Quiliano (Liguria Region, Northern Italy) is located. MAIN OUTCOME MEASURES: individual life shortening. RESULTS: after 5 years of follow up, the individual life shortening due to cardiorespiratory causes varied between 972 and 1,822 days for males and from 612 and 1,578 days among females. Taking into account other causes of death, reduces slightly (3% for males of 75 years at death) the estimate of life shortening found in this study. The comparison between the cohorts requires that the exposed and unexposed groups are comparable, except for the exposure, and that causes other than those considered are taken into account. Socioeconomic status had been found to have little effect on cause-specific death risk indicating that, at least in terms of socioeconomic status, the exposed and unexposed groups were similar. Taking into account causes other than those considered slightly reduced the found estimates (3% at age 75 in males). According to the proposal, the life-shortening for the considered causes is easy to calculate and provides an individual indicator of damage. Inferring from group statistics individual estimates could be the most controversial point of this approach. The proposed estimates are the most credible estimate of individual damage for each occurred death among the exposed people. CONCLUSIONS: an increased hazard ratio for a wide series of causes is equivalent to a life shortening among the exposed. A method to produce reasonable estimates of life-shortening is proposed as the effect of exposure at individual level. This approach is simple and do not require sophisticated statistical tools. It appears a promising approach for other settings.


Assuntos
Carbono , Doenças Cardiovasculares , Exposição Ambiental , Centrais Elétricas , Doenças Respiratórias , Idoso , Idoso de 80 Anos ou mais , Carbono/envenenamento , Doenças Cardiovasculares/mortalidade , Causas de Morte , Cidades/epidemiologia , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Respiratórias/mortalidade
2.
Environ Sci Technol ; 55(13): 9074-9086, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34132542

RESUMO

Children who live near coal-fired power plants are exposed to coal fly ash, which is stored in landfills and surface impoundments near residential communities. Fly ash has the potential to be released as fugitive dust. Using data collected from 263 children living within 10 miles of coal ash storage facilities in Jefferson and Bullitt Counties, Kentucky, USA, we quantified the elements found in nail samples. Furthermore, using principal component analysis (PCA), we investigated whether metal(loid)s that are predominately found in fly ash loaded together to indicate potential exposure to fly ash. Concentrations of several neurotoxic metal(loid)s, such as chromium, manganese, and zinc, were higher than concentrations reported in other studies of both healthy and environmentally exposed children. From PCA, it was determined that iron, aluminum, and silicon in fly ash were found to load together in the nails of children living near coal ash storage facilities. These metal(loid)s were also highly correlated with each other. Last, results of geospatial analyses partially validated our hypothesis that children's proximity to power plants was associated with elevated levels of concentrations of fly ash metal(loid)s in nails. Taken together, nail samples may be a powerful tool in detecting exposure to fly ash.


Assuntos
Cinza de Carvão , Centrais Elétricas , Criança , Carvão Mineral , Cinza de Carvão/análise , Poeira/análise , Humanos , Metais
3.
Environ Monit Assess ; 193(7): 432, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34152479

RESUMO

This study aimed at upgrading the Air Indicator Report for Public Awareness and Community Tracking (Airpacts) model to evaluate the physical effects of sulfur dioxide (SO2) emissions from Shahid Rajaee power plant on the building façades in Qazvin, Iran in 2018. For this purpose, first, the methodological requirements of the model for the study area, including wind speed, relative humidity, and temperature, were analyzed. Then, the concentration of SO2 emission from the power plant stack was calculated using the Aeroqual Model 200. The obtained data were processed and loaded into the Airpacts model version 1.0. After localization of the costs for reconstruction of 1 m2 of façade, including the costs of purchasing materials, installation, and transport from the power plant, the damage posed by SO2 to the building façades in Qazvin was calculated. Outputs of the modified model suggested that the damage to the building façades included cleansing in contact with SO2 was 494,558,878.12 m2. Based on the calculations, the cost of damage caused by SO2 was estimated to be $0.25 per Megawatt-hour (MWh) electricity generation, reaching an amount of $29,422 annually. Based on the localized results obtained by the modified Airpacts, the external cost of damage to the façades was $0.3 per MWh electricity generation, reaching an amount of $35,720 annually. To overcome the constraints of the original model concerning the constant parameters of mixing height and wind speed in the default model algorithm, the two parameters were considered dynamic variables in the modified model.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental , Irã (Geográfico) , Centrais Elétricas , Dióxido de Enxofre/análise
4.
Environ Sci Technol ; 55(10): 7094-7101, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33955737

RESUMO

Capturing gaseous Hg0 using regenerable metal sulfides is a promising technology to recover gaseous Hg0 from both coal-fired flue gas (CFG) and smelting flue gas (SFG) for the centralized control. Gaseous Hg0 concentration in SFG is 2-3 orders of magnitude higher than that in CFG; therefore, the design strategy of metal sulfides for capturing gaseous Hg0 from CFG is quite different from that from SGF. In this work, the structure-activity relationship of metal sulfides to capture Hg0 was investigated according to the remarkable difference in MoO3 loading on sulfureted FeTiOx to capture low/high concentrations of gaseous Hg0. The rate of Hg0 adsorption onto metal sulfides was mainly related to the amounts of adsorption sites and S22- on the surface, the affinity of adsorption sites to gaseous Hg0, and the gaseous Hg0 concentration. Meanwhile, the capacity for Hg0 adsorption was approximately equal to the less of the amount of adsorption sites and S22- on the surface. Furthermore, capturing low concentrations of gaseous Hg0 from CFG required the metal sulfide sorbents having more adsorption sites with strong affinity to gaseous Hg0, while capturing high concentrations of gaseous Hg0 from SFG required the sorbents with enough adsorption sites.


Assuntos
Gases , Mercúrio , Adsorção , Carvão Mineral , Centrais Elétricas , Sulfetos
5.
Environ Sci Technol ; 55(11): 7595-7604, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33979128

RESUMO

Captured CO2 is a potential feedstock to produce fuel/chemicals using renewable electricity as the energy source. We explored resource availability and synergies by region in the United States and conducted cost and environmental analysis to identify unique opportunities in each region to inform possible regional and national actions for carbon capture and utilization development. This study estimated production cost of synthetic methanol and Fischer-Tropsch (FT) fuels by using CO2 captured from the waste streams emitted from six industrial [ethanol, ammonia, natural gas (NG) processing, hydrogen, cement, and iron/steel production plants] and two power generation (coal and NG) processes across the United States. The results showed that a total of 1594 million metric ton per year of waste CO2 can be captured and converted into 85 and 319 billion gallons of FT fuels and methanol, respectively. FT fuels can potentially substitute for 36% of the total petroleum fuels used in the transportation sector in 2018. Technoeconomic analysis shows that the minimum selling prices for synthetic FT fuels and methanol are 1.8-2.8 times the price of petroleum fuel/chemicals, but the total CO2 reduction potential is 935-1777 MMT/year.


Assuntos
Carbono , Metanol , Dióxido de Carbono , Carvão Mineral , Centrais Elétricas , Estados Unidos
6.
J Environ Manage ; 292: 112717, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34015611

RESUMO

As an effective emission reduction approach, CO2 capture and storage (CCS) combined with enhanced water recovery (EWR) technology can not only reduce CO2 emissions, but can also recover deep saline water resources to relieve pressure on regional water resources, and can ensure the energy supply and both social and economic development. However, the environmental benefits and application costs of CCS-EWR are uncertain, and are determined by the technology level, geological conditions, and other physical factors. In this study, an optimal source-sink matching model and a techno-economic assessment model were developed to evaluate the contributions of CCS-EWR to carbon emission reduction and the increase of the water supply by considering various uncertain factors, as well as the corresponding costs. In addition, the Yellow River Basin (YRB) in China was selected as the research region because, while there are abundant coal-fired power plants (CFPPs) in the YRB, the water resources are scarce. The results revealed the following. (1) The maximum CO2 capture capacity of the 236 CFPPs in the YRB is about 738.77 Mt/a, and nearly 13.14 Gt of fresh water could be provided until the 236 CFPPs in the YRB retire, which can partially relieve the pressure on the supply of water resources. (2) With the consideration of the CCS-EWR benefits, the average cost of the 236 CFPPs in the YRB in their residual lifetime to reduce their CO2 emissions by 90% will be no more than 180 CNY/t. (3) The incentive effect of the increase of the industrial water price on the profits of CCS-EWR projects is not significant. CCS-EWR technology has better application prospects in China under the dual constraints of carbon-neutral targets and water shortages, and more policy support is required for its deployment.


Assuntos
Carvão Mineral , Água , Dióxido de Carbono/análise , China , Carvão Mineral/análise , Centrais Elétricas , Rios , Tecnologia
7.
Environ Pollut ; 283: 117397, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030063

RESUMO

Hg is a global concern given its adverse effects on human health, food security and the environment, and it requiring actions to identify major local Hg sources and to evaluate pollution. Our study provides the first assessment of Hg stock trends on the entire Majorca surface, identifying major Hg sources by studying the spatiotemporal soil Hg variation at two successive times (2006 and 2016-17). The Hg soil concentration ranged from 14 to 258 µg kg-1 (mean 52 µg kg-1). Higher concentrations (over 100 µg kg-1) were found in two areas: (i) close to the Alcudia coal-fired power plant; (ii) in the city of La Palma. During the 11-year, the total Hg stock in Majorcan soil increased from 432.96 tons to 493.18 tones (14% increase). Based on a block kriging analysis, soil Hg enrichment due to power plant emissions was clearly detectable on a local scale (i.e. a shorter distance than 18 km from the power plant). Nonetheless, a significant island-wide Hg increase due to diffuse pollution was reported. This result could be extrapolated to other popular tourist destinations in the Mediterranean islands where tourism has increased in recent decades In short, more than 60 tons of Hg have accumulated on Majorca island in 11 years.


Assuntos
Mercúrio , Poluentes do Solo , Carvão Mineral/análise , Monitoramento Ambiental , Humanos , Ilhas , Ilhas do Mediterrâneo , Mercúrio/análise , Centrais Elétricas , Solo , Poluentes do Solo/análise , Espanha
8.
Waste Manag ; 128: 99-113, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33975140

RESUMO

The effects of amending municipal solid waste incineration (MSWI) with carbon capture and storage (CCS) via MEA (Monoethanolamine) technology differ according to the air pollution control technologies and energy recovery systems. Electricity output reduces by one-third for power-only plants and halves for combined heat-and-power plants, while variations in heat recovery depend on the presence of flue gas condensation. MSWI with CCS can capture roughly 800 kg of compressed CO2 per tonne of waste treated. Life cycle assessment (LCA) modelling of MSWI, with and without CCS, illustrates that despite energy penalties, CCS lowers its climate change impact. The difference in climate change impacts as a result of CCS amendment depends on the energy system in which MSWI operates. In a near-future energy system, MSWI with CCS reduces climate change impacts by 700 kg CO2-eq/tonne wet waste compared to MSWI without CCS. The climate change saving of CCS became increasingly larger as the energy system became "greener"; the climate change saving ultimately approached the capture efficiency (85% of CO2 in the flue gas) multiplied by the carbon content of the waste converted to CO2. Sensitivity analysis showed that capture efficiency was the main factor affecting the overall results, with increasing importance in non-fossil fuel-based energy systems. Likely changes in residual waste composition, as source segregation and collection systems improve, had only minor effects on the environmental benefits of CCS. The effects of CCS amendments on 13 other impact categories were marginal compared to the effects of different MSWI configurations.


Assuntos
Carbono , Incineração , Centrais Elétricas , Resíduos Sólidos/análise , Tecnologia
9.
Front Public Health ; 9: 613517, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968876

RESUMO

In this study, we estimate the health benefits of more stringent alternative energy goals and the costs of reducing coal-fired power plant pollution in China projected in 2030. One of our two overarching alternative energy goals was to estimate the health benefits of complete elimination of coal energy, supplemented by natural gas and renewables. The second was a policy scenario similar to the U.S. 2013 Climate Action Plan (CAP), which played a pivotal role leading up to the 2015 Paris Climate Agreement. We used the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model created by the International Institute for Applied Systems Analysis for our model simulations. We found that 17,137-24,220 premature deaths can be avoided if coal energy is completely replaced by alternative energy, and 8,693-9,281 premature deaths can be avoided if coal energy is replaced by alternatives in a CAP-like scenario. A CAP-like scenario using emission-controls in coal plants costs $11-18 per person. Reducing coal energy in China under a CAP-like scenario would free up $9.4 billion in the annual energy budget to spend on alternatives, whereas eliminating the cost of coal energy frees up $32 billion. This study's estimates show that more stringent alternative energy targets in China are worth the investment in terms of health.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , China/epidemiologia , Carvão Mineral , Humanos , Centrais Elétricas
10.
Radiat Prot Dosimetry ; 194(1): 57-64, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-33993315

RESUMO

In this study, electric field and magnetic field strengths at 50 Hz are measured in a solar power plant located far from residential areas, and the measurement results near various sources of the electric and magnetic fields in the power plant are presented. Although the measured values for the electric field caused by the solar panel range between 0.07 and 1.33 V/m, the measured values for the magnetic field by the solar panel range between 0.037 and 0.19 µT. In front of the inverter, the measured value of the electric field reaches 0.7 V/m, whereas the measured value of the magnetic field reaches 2.2 µT. The results are presented and evaluated in light of the exposure limits to electromagnetic fields published by international organisations.


Assuntos
Campos Eletromagnéticos , Energia Solar , Eletricidade , Centrais Elétricas
11.
Waste Manag ; 130: 30-37, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34044362

RESUMO

The selection of fuel for a Combined Heat and Power (CHP) plant can vary over time. By choosing less expensive fuels, operation costs are reduced, however, cheaper fuels generally increase corrosion maintenance costs. The corrosiveness of different fuels has been studied extensively while how the current corrosion attack is influenced by corrosion history, i.e. previous deposit build-up and oxide scale formation, is less studied. This phenomenon may be referred to as a "corrosion memory" effect (Paz et al., 2017). The present work investigates the influence of addition of sulfur to the fuel on the corrosion memory through air-cooled probes in the Waste-to Energy lines at Måbjerg Energy Center (MEC) in Denmark. The results show a corrosion memory effect, i.e. as initially corrosive environment may increase the subsequent corrosion rate and vice versa.


Assuntos
Temperatura Alta , Enxofre , Corrosão , Centrais Elétricas , Temperatura
12.
J Acoust Soc Am ; 149(4): 2238, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33940893

RESUMO

Even though some individuals subjectively associate various symptoms with infrasound, there are very few systematic studies on the contribution of infrasound to the perception, annoyance, and physiological reactions elicited by wind turbine sound. In this study, sound samples were selected among long-term measurement data from wind power plant and residential areas, both indoors and outdoors, and used in laboratory experiments. In the experiments, the detectability and annoyance of both inaudible and audible characteristics of wind turbine noise were determined, as well as autonomic nervous system responses: heart rate, heart rate variability, and skin conductance response. The participants were divided into two groups based on whether they reported experiencing wind turbine infrasound related symptoms or not. The participants did not detect infrasonic contents of wind turbine noise. The presence of infrasound had no influence on the reported annoyance nor the measured autonomic nervous system responses. No differences were observed between the two groups. These findings suggest that the levels of infrasound in the current study did not affect perception and annoyance or autonomic nervous system responses, even though the experimental conditions corresponded acoustically to real wind power plant areas.


Assuntos
Ruído , Centrais Elétricas , Humanos , Percepção
13.
Artigo em Inglês | MEDLINE | ID: mdl-33923606

RESUMO

In order to cope with recent climate change, Korea is reducing the use of heavy oil in petroleum-fired power plants and mixing bio-oils. Accordingly, this must be taken into account when calculating the emissions of air pollutants. However, in the case of Korea, when calculating NH3 emissions, the United States Environmental Protection Agency (EPA) emission factor is applied as it is to calculate emissions, and for petroleum power plants, the heavy oil emission factor proposed by EPA is used as it is to calculate emissions. In petroleum power plants, bio-oil is not mixed in a certain amount and used at a different ratio depending on the situation of the power plant. Therefore, in this study, the NH3 emission factor according to the mixing ratio of bio-heavy oil is calculated and the mixing ratio is calculated. As a result of the analysis, the emission factor according to bio-oil and the mixed ratio was found to be in the range of 0.010~0.033 kg NH3/kL, and it was lower than the heavy oil emission factor 0.096 kg NH3/kL of EPA currently used in Korea. This is because the amount of NH3 through the slip is also small since the use of NH3 for reduction is also low because the NOx emission from the use of bio-oil is low. Considering all of these points, we have statistically analyzed whether emission factors should be developed and applied. As a result of the confirmation, the difference according to the mixed consumption rate was not large.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Amônia , Monitoramento Ambiental , Óleos Vegetais , Polifenóis , Centrais Elétricas , República da Coreia , Estados Unidos
14.
J Environ Manage ; 290: 112367, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33878632

RESUMO

Air pollution currently poses a serious threat to human health and sustainable development in China. In an attempt to reduce nitrogen oxides (NOX) emissions which are the major anthropogenic contributors to air pollution, China initiated an electricity price subsidy (EPS) policy in November 2011 for incentivizing coal-fired power plants to install denitrification units. However, the effectiveness of the policy in the reduction of NOX emissions and its sustainability are yet to be investigated. This study attempts to examine the effects of the EPS policy on NOX emissions and NOX removal, based on a panel-data set covering 113 prefectural-level cities in China during 2008-2015. Using a difference-in-differences (DID) regression model, we find that for each additional power plant in cities, the EPS policy significantly reduces NOX emissions by 1.1% and increases NOX removal by 2.8%. Furthermore, the results reveal that the overall effect of the EPS policy shows a positive trend with time accompanied by an increase in price subsidy, indicating that the efficacy of the policy designed for the reduction of harmful air pollutants is sustainable. In particular, we confirm that compensating for the construction and operation costs of denitrification units is an effective mechanism which encourages the coal-fired power plants to invest more in such units. The findings of the study accentuate the significant implication that economic-incentive policies play a crucial role in combating air pollution and environmental degradation.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , China , Carvão Mineral/análise , Eletricidade , Humanos , Políticas , Centrais Elétricas
15.
J Environ Manage ; 290: 112659, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33894485

RESUMO

Low-carbon power generation has been proposed as the key to address climate change. However, the sustainability and ecological efficiency of the generating plants have not been fully understood. This study applies emergy analysis and systems accounting to a pilot solar power tower plant in China for the first time to elaborate its sustainable and ecological performances. Emergy analysis covers virtually all aspects of sustainability and ecological efficiency by considering different forms of materials inputs, environmental support and human labor on the same unit of "solar joule". The input-output analysis based systems accounting is applied to trace the complete emergy embodied in the supply chain for all product materials of the given plant against the back ground of complex economic network, which improved the accuracy of accounting. This analysis illustrated unexpectedly low sustainability and ecological efficiency of this particular plant compared with the emergy analysis based on the primary materials (steel, iron, cement, etc.). Purchased emergy responses more than 95% of the total and emergy input in the construction phase is more than twice as much as that in the operation phase. Comparisons with other kinds of clean energy technologies indicate previous studies may have overestimated the sustainability and ecological benefits of low-carbon power plants. Thus, it is necessary to establish this kind of unified accounting framework. In addition, sensitivity analysis suggests that strictly controlling monetary costs of purchased inputs, extending service lifetime and improving power generation efficiency can promote higher sustainability and ecological efficiency for solar power tower plants. This study provides a more comprehensive framework for quantitative emergy-based evaluation of the sustainability and ecological efficiency for low-carbon power systems.


Assuntos
Conservação dos Recursos Naturais , Energia Solar , Carbono , China , Ecossistema , Humanos , Centrais Elétricas
16.
Waste Manag ; 126: 578-584, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33864986

RESUMO

The progressive decarbonisation of industry is leading to a reduction in coal consumption and the substitution for coal with other types of fuels, including waste-derived alternative fuels. These fuels are characterised by high variation in the content of highly toxic mercury. Co-combustion with coal can cause significant emissions, exceeding mercury emission limits. Various alternative fuels (refuse-derived fuel (RDF), waste paper, textiles, plastics, film, tires and their char, and sewage sludge) were examined for mercury content. The mercury content in analysed alternative fuels ranged from 0.4 to 92.0 µg Hg/MJ, with an average of 17.7 µg Hg/MJ. The fuels with the highest mercury content were RDFs (2.0-79.3 µg Hg/MJ) and sewage sludge (42.3-92.0 µg Hg/MJ). An acceptable amount of RDF added to hard coal which would remain within the emission limits was estimated to be 9-24% of the chemical energy in the blend. For sewage sludge, this amount was estimated to be 5-13%. For brown coal, with a much higher mercury content than hard coal, co-combustion with alternative fuels has a positive effect on reducing mercury emissions. It is possible to meet the mercury emission limits with a 95% contribution of the chemical energy coming from RDF. The blending of various types of waste supported by mild pyrolysis of high-mercury waste allows alternative fuels with relatively low mercury content to be produced. Such fuels may contribute a reduction in mercury emissions from coal-fired power plants in Poland.


Assuntos
Poluentes Atmosféricos , Mercúrio , Poluentes Atmosféricos/análise , Carvão Mineral/análise , Indústrias , Mercúrio/análise , Polônia , Centrais Elétricas
17.
J Environ Radioact ; 233: 106574, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33798809

RESUMO

Natural radioactivity is released into the environment during the combustion process of coal at various thermal power plants. Coal contains higher contents of α-emitting radionuclides such as 238U, 232Th along with their decay elements, which pose a potential health risk to the population. In the present studies, the effluent waste samples were collected from a coal fired Thermal Power Plant. Samples were collected in the form of solid residues and filtrates. CR-39 detector pieces were then exposed for varying time with residue and filtrate samples for registering the alpha tracks for α-detection and measurement. Thus, registered alpha particles in CR-39 detectors were revealed by employing the conventionally used 6M NaOH/KOH etchant and 5% tetraethyl ammonium bromide (TEAB) as a phase transfer catalyst in 6M NaOH/KOH etchant. Under both compositions of the etchants, CR-39 detectors were etched at 60 °C for 6 h for developing alpha tracks for observations under optical transmission microscope. Alpha track densities (Td) and alpha track diameters in the etched CR-39 detectors for all samples were measured. The introduction of new chemical etchant effectively improved the uniformity in distribution of alpha tracks, enhanced the track density, and reduced the time of track revelation in CR-39 detectors. Therefore, it could be concluded that the phase transfer catalyst TEAB was highly effective in the etchant for alpha track revelation and detection as compared to conventionally used 6M NaOH etching method. Apart from measuring alpha radio activities, the amounts of 238U & 232Th in the samples were also measured by ICP-MS for understanding the alpha radio activities measured in the coal samples.


Assuntos
Monitoramento de Radiação , Radioatividade , Polietilenoglicóis , Centrais Elétricas
19.
Chemosphere ; 276: 130084, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33740650

RESUMO

Anthropogenic NOx, SO2 and CO2 emission from the fossil-fuel-fired power plants has aroused growing attention. This study investigated the removal performance of CO2, SO2 and NOx in flue gas as well as conversion efficiency of nitric- and sulfur-compounds in liquid phase in a biofilter. In order to develop the potential of the biofilter, simulative industry wastewater was employed as the spray solution. The satisfactory flue gas removal performance (75.23% CO2, 100% SO2 and 82.81% NO) were achieved under the optimal operating conditions of biofilter: initial solution pH of 9 and liquid-gas ratio (L/G) of 3. The gas film mass transfer coefficients (kGa) results showed that the resistance of gas mass transfer was decreased with increasing the pH value and L/G ratio, respectively. The final transformation product of NO was mostly N2 while about 78% SO2 was converted to elemental sulfur. The microbial community analysis results showed that the relative abundance of bacteria with denitrification capacity was increased by 3.05% which might have contributed to the conversion of NO intermediates products in present study. Collectively, this biofilter system achieve a better flue gas removal performance via the proper operation system, which provides an economic feasible strategy of flue gas purification and increases potential for industrial application.


Assuntos
Dióxido de Carbono , Dióxido de Enxofre , Bactérias/genética , Óxido Nítrico , Centrais Elétricas
20.
Am J Public Health ; 111(5): 881-889, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33734848

RESUMO

Objectives. To investigate the effects of coal-fired power plant closures on zip code-level rates of emergency department visits for asthma-related conditions among 0- to 4-year-old children in Chicago, Illinois.Methods. We used data on wind, population, PM2.5 (particulates measuring ≤ 2.5 µm in diameter), and zip code-level rates of emergency department visits for asthma-related conditions among 0- to 4-year-old children between 2009 and 2017 in Chicago. The difference-in-differences research design compared rates of emergency department visits in zip codes near 3 coal-fired power plants before and after their closures to rates in zip codes farther away during the same time period.Results. We found that emergency department visits for asthma-related conditions among 0- to 4-year-old children decreased by 12% in zip codes near the 3 coal-fired power plants following their closures relative to rates in zip codes farther away during the same period. The crude and age-specific rates of emergency department visits decreased by 2.41 visits per ten thousand inhabitants and 35.63 visits per ten thousand children aged 0 to 4 years, respectively.Conclusions. Our findings demonstrate that closing coal-fired power plants can lead to improvements in the respiratory health of young children.


Assuntos
Asma/epidemiologia , Carvão Mineral , Serviço Hospitalar de Emergência/estatística & dados numéricos , Material Particulado/análise , Centrais Elétricas/estatística & dados numéricos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Chicago/epidemiologia , Pré-Escolar , Exposição Ambiental/análise , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Características de Residência , Análise Espacial , Tempo (Meteorologia)
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