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1.
Environ Monit Assess ; 192(11): 699, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044641

RESUMO

The present study was intended to determine the potentially toxic elements (PTEs) concentration in fly ash (FA), soil, plant, and vegetable to assess the impacts of pollution on the nearby areas of coal-fired thermal power plant (TPP). The PTEs concentrations (mg/kg) in FA were Cr (48-74) > Pb (41-65) > Cd (7.4-9.7) > As (3.19-4.43) > Hg (0.518-0.598). The contamination factor (Cf) for Cd was highest in agricultural soil (Cf = 22) followed by roadside soil (Cf = 20), and forest soil (Cf = 15), which showed that the soil was strongly polluted due to the presence of Cd. The ecological risk index (ERI) in the topsoil of roadside area was also very high (1130), due to the high value of ecological risk factor of Cd (898) and Hg (213). The health risk associated with the intake of soil containing PTEs were also estimated by calculating hazard index (HI), and the values showed that the risk posed to children was minimum (HI < 1). But in case of roadside area, the HI was very close to one (0.975) indicating that the prolong exposure may pose severe health risk. The bioaccumulation coefficient of all PTEs for Albizia lebbeck and Madhuca longifolia were < 1, indicating less PTEs accumulation in the plant species. The hazard quotient of all PTEs (except of Hg) through vegetable consumption (Allium cepa and Raphanus sativus) was > 1, which signifies that the long-time consumption of contaminated vegetables may cause severe risk to the people.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , Carvão Mineral , Monitoramento Ambiental , Humanos , Índia , Metais Pesados/análise , Centrais Elétricas , Medição de Risco , Solo , Poluentes do Solo/análise , Verduras
2.
Environ Monit Assess ; 192(10): 652, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32964332

RESUMO

Location selection for offshore wind farms is a major challenge for renewable energy policy, marine spatial planning, and environmental conservation. This selection constitutes a multi-criteria decision-making problem, through which parameters like wind velocity, water depth, shorelines, fishing areas, shipping routes, environmental protection areas, transportation, and military zones should be jointly investigated. The aim of the present study was thus to develop an integrated methodology for assessing the siting of bottom-fixed offshore wind farms in two different countries (with different legal, political, and socio/economic characteristics). Our methodology combined multi-criteria decision-making methods and geographical information systems and was implemented in Cyclades (Greece) and in the sea area of Izmir region (Turkey). Experts used fuzzy sets and linguistic terms to achieve more consistent and independent rankings and results. In the Turkish region, the results showed that 519 km2 (10.23%) of the study area is suitable for offshore wind farms, while in the Greek region, only 289 km2 (3.22%) of the study area was found to be suitable. This spatial suitability analysis may contribute to provide some useful recommendations for the spatial marine planning at the regional scale, as well as for the preliminary assessment of new offshore wind farms in both countries.


Assuntos
Fontes Geradoras de Energia , Sistemas de Informação Geográfica , Monitoramento Ambiental , Grécia , Centrais Elétricas , Turquia , Vento
3.
Environ Pollut ; 266(Pt 3): 115282, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32799176

RESUMO

The comparison of fly ash generated from lignite combustion in a thermal power plant Kolubara A (Veliki Crljeni) and bottom and fly ash from coal waste combustion in a semi-industrial fluidized bed boiler (Vinca) was performed as the function of particle size. The average total concentrations of the 16 EPA priority PAHs in ash fractions are 0.49 mg kg-1 of ash (thermal power plant) and 17.48 mg kg-1 of ash (fluidized bed boiler). The sum of 3- and 4-ring PAHs accounts for more than 93% of overall PAHs concentration, and the most abundant among them is fluoranthene. The portions of PAHs groups defined based on their physico-chemical properties, as obtained from quantitative structure-activity relationship (QSAR) models included in the Vega platform, were determined. These portions, emission factors, and benzo[a]pyrene equivalence concentrations were further on used to estimate the potential environmental impact of ash disposal. The PAHs emission factors are higher compared to values in the air pollutant emission inventory guidebook of the cooperative program for monitoring and evaluation of the long-range transmission of air pollutants in Europe (EMEP/EEA). The overall emission factors of 16 PAHs for combustion of lignite and coal waste are determined to be 0.15 and 249.97 mg kg-1 of fuel, respectively. Based on the ratios of benzo[a]pyrene equivalence concentrations of each ash and correspondent fuel, the disposal of fly ash from the cyclone of fluidized bed boiler represents the highest risk to the environment among tested ashes.


Assuntos
Cinza de Carvão/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Carvão Mineral/análise , Europa (Continente) , Incineração , Centrais Elétricas
4.
PLoS One ; 15(8): e0236958, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760117

RESUMO

Renewable electricity can fully decarbonise the European electricity supply, but large land requirements may cause land-use conflicts. Using a dynamic model that captures renewable fluctuations, I explore the relationship between land requirements and total system cost of different supply-side options in the future. Cost-minimal fully renewable electricity requires some 97,000 km2 (2% of total) land for solar and wind power installations, roughly the size of Portugal, and includes large shares of onshore wind. Replacing onshore wind with offshore wind, utility-scale PV, or rooftop PV reduces land requirements drastically with only small cost penalties. Moving wind power offshore is most cost-effective and reduces land requirements by 50% for a cost penalty of only 5%. Wind power can alternatively be replaced by photovoltaics, leading to a cost penalty of 10% for the same effect. My research shows that fully renewable electricity supply can be designed with very different physical appearances and impacts on landscapes and the population, but at similar cost.


Assuntos
Eletricidade , Energia Renovável , Conservação de Recursos Energéticos/economia , Conservação dos Recursos Naturais/economia , Análise Custo-Benefício , Custos e Análise de Custo , Europa (Continente) , Modelos Teóricos , Recursos Naturais , Centrais Elétricas/economia , Energia Renovável/economia , Energia Solar/economia , Processos Estocásticos , Vento
5.
PLoS One ; 15(8): e0235668, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776932

RESUMO

In this paper, a novel, effective meta-heuristic, population-based Hybrid Firefly Particle Swarm Optimization (HFPSO) algorithm is applied to solve different non-linear and convex optimal power flow (OPF) problems. The HFPSO algorithm is a hybridization of the Firefly Optimization (FFO) and the Particle Swarm Optimization (PSO) technique, to enhance the exploration, exploitation strategies, and to speed up the convergence rate. In this work, five objective functions of OPF problems are studied to prove the strength of the proposed method: total generation cost minimization, voltage profile improvement, voltage stability enhancement, the transmission lines active power loss reductions, and the transmission lines reactive power loss reductions. The particular fitness function is chosen as a single objective based on control parameters. The proposed HFPSO technique is coded using MATLAB software and its effectiveness is tested on the standard IEEE 30-bus test system. The obtained results of the proposed algorithm are compared to simulated results of the original Particle Swarm Optimization (PSO) method and the present state-of-the-art optimization techniques. The comparison of optimum solutions reveals that the recommended method can generate optimum, feasible, global solutions with fast convergence and can also deal with the challenges and complexities of various OPF problems.


Assuntos
Algoritmos , Eletricidade , Dinâmica não Linear , Simulação por Computador , Centrais Elétricas , Software
7.
Waste Manag ; 115: 83-94, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32731137

RESUMO

The European Union is aiming at a circular economy and increased resource efficiency, which requires a waste management at the end-of-life of products. This is especially challenging for new and innovative products for which no recycling infrastructure exists so far. Wind power plants are such a product, for which large amounts of waste are expected within the next years as more and more plants reach their end-of-life. Especially the end-of-life rotor blades of wind power plants pose challenges with regard to waste management, since treatment options for the installed glass and carbon fiber reinforced plastics are still in a development stage. Moreover, material specific characteristics and technical aspects require separate treatment of these materials. To plan efficient treatment infrastructure, detailed knowledge on future waste streams is required. Against this background, this paper aims at estimating the mass of glass and carbon fiber reinforced plastic waste from rotor blades. To do so, we derive material specific weight functions and material specific shares to calculate the amount of installed glass and carbon fiber reinforced plastics in rotor blades. We apply normally distributed life times to project the calculated installed masses into the future and account for uncertainties within a simulation study. The estimation model is applied to a dataset of wind power plants within the European Union. Based on the considered dataset, we estimate that 570 [Mt] of fiber reinforced plastic waste will occur between 2020 and 2030 in the European Union of which 18 [Mt] are carbon fiber reinforced plastic waste.


Assuntos
Fibra de Carbono , Vento , União Europeia , Plásticos , Centrais Elétricas , Reciclagem
8.
Environ Pollut ; 266(Pt 3): 115103, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32650303

RESUMO

Biomass integrated gasification combined cycle (IGCC) is attracting increased interest because it can achieve high system energy efficiency (>50%), which is predicted to increase with the increase in the solar share in biomass IGCC. This study evaluated the potential of crop residues numerically for the co-production of power and bio-fertilizer using ASPEN Plus® simulation software. The results showed that the gas yield increases with increasing temperature and decreasing pressure while the yield of bio-fertilizer is dependent on the biomass composition. The biomass with a low ash content produces high bio-fertilizer at the designated gasification temperature. The IGCC configuration conserves more energy than a directly-fired biomass power plant. In addition, the solar-assisted IGCC attains a higher net electricity output per unit of crop residue feed and achieves net thermal efficiencies of around 53%. The use of such hybrid systems offer the potential to produce 0.55 MW of electricity per unit of solar-thermal energy at a relatively low cost. The ASPEN Plus model predicted that the solar biomass-based IGCC set up is more efficient in increasing the power generation capacity than any other conversion system. The results showed that a solar to electricity efficiency of approximately 55% is achievable with potential improvements. This work will contribute for the sustainable bioenergy production as the relationship between energy production and biomass supplies very important to ensure the food security and environmental sustainability.


Assuntos
Fertilizantes , Energia Solar , Biomassa , Eletricidade , Centrais Elétricas
9.
Environ Monit Assess ; 192(8): 541, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32710394

RESUMO

Coal preparation by-products, such as coal gangue, are inferior fuels enriched with trace elements (TEs). Owing to the issues surrounding the disposal of coal preparation by-products and energy shortages, Chinese researchers have strongly advocated harvesting energy from by-products. However, the secondary environmental pollution caused by such by-products has been overlooked. In this study, we aimed to assess the contamination of soil and maize (Zea mays L.) near a coal gangue-fired power plant (CGPP) in Liupanshui City, Guizhou Province, China, by TEs. The contents of 11 TEs (Be, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, V, and Zn) in soil samples and different maize tissues were measured, and their chemical speciation in soil was also determined. The results showed that the soil in the study area was polluted by the above elements to varying degrees at a very high potential ecological risk. The Cr and Pb levels in niblets of partial samples exceeded the Chinese food safety standards. The TE contents of maize tissues largely depend on the bioavailable fraction of the same elements in the soils, rather than their total contents. Pearson's correlation and hierarchical cluster analyses resulted in three clusters:(1) Pb-Zn-Cd; (2) Co-Cu-Mn-Sb-V-Be; and (3) Cr-Ni. Coal preparation by-products should not be directly combusted without pre-treatment. These results will aid readers and engineers in understanding the adverse effect of CGPPs and provide regulators and policymakers with relevant data to scientifically guide the utilisation of coal preparation by-products.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , China , Carvão Mineral/análise , Monitoramento Ambiental , Centrais Elétricas , Medição de Risco , Solo , Zea mays
10.
Bull Environ Contam Toxicol ; 105(3): 502-512, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32728825

RESUMO

In India, coal utilization in power generation, constitutes as the single largest source of mercury emissions. This study presents mercury content in Indian sub-bituminous and bituminous coals that are primarily used as fuel in large-scale electricity generation facilities. A total of 165 number of coal samples have been collected from the major coal producing regions of the country. Along with the mercury content, other chemical parameters like moisture, ash, volatile matter, total Sulphur and gross calorific value were also analyzed. Mercury concentrations of these coals were found to be between 3 and 554 µg/kg, with an average of 175 µg/kg. Variation of the mercury content with the rank parameters like volatile matter, carbon content, ash and total Sulphur were also assessed. No significant correlations were observed with the rank parameters but a general trend of increasing mercury with ash content is discernible.


Assuntos
Poluentes Atmosféricos/análise , Carvão Mineral/análise , Mercúrio/análise , Centrais Elétricas , Carbono/análise , Cinza de Carvão , Monitoramento Ambiental , Índia , Enxofre
11.
J Environ Manage ; 270: 110862, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721309

RESUMO

To what extent do the short-term negative externalities of fossil fuel use traverse national borders? Transnational negative externalities are thought to motivate international environmental cooperation, but we often lack detailed data on their occurrence. Using a Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT), we offer global estimates of the extent of transboundary air pollution from coal-fired power generation. In an advance of the existing literature, we attribute the air pollution experienced in different locales to specific coal-fired power plants, allowing us to evaluate the extent to which pollution from the coal industry is experienced across different jurisdictions. Our results indicate that the issue is most severe in South Asia and East Asia. When weighting by the population of "receiving" locations, India is found to be the largest emitter of transboundary air pollution, followed by China. Residents of Bangladesh are found to experience the most transboundary air pollution by a wide margin.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Ásia , Bangladesh , China , Carvão Mineral/análise , Índia , Centrais Elétricas
12.
Environ Sci Pollut Res Int ; 27(27): 34357-34368, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32557069

RESUMO

In recent years, the Chinese government has proposed a policy to replace coal use with natural gas and electricity in the northern region to reduce the air pollution caused by the large consumption of coal. In order to assess the air pollution reduction effect of the coal substitution policy in Liaoning Province, this paper proposes a data grouping grey model with a fractional order accumulation (FDGGM (1,1)). The empirical analysis results show that the new grey model can predict the monthly coal consumption more accurately than the traditional DGGM (1,1) model. The MAPEs of the training set in the FDGGM(1,1) and DGGM(1,1) models are 4.58% and 5.48%, and the MAPEs of the test set are 23.89% and 33.78%, respectively. And the policy achieves a great success based on the FDGGM(1,1) model. During the policy implementation period (from January 2015 to December 2018), the coal consumption in Liaoning Province decreased by 27.2501 million tons, while the emissions of CO2, SO2 and NOx fell by 0.714, 0.2316 and 0.2017 million tons, respectively. The results also provide a necessary support to the further implementation of the coal substitution policy.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Carvão Mineral/análise , Gás Natural , Centrais Elétricas
13.
Environ Sci Pollut Res Int ; 27(29): 36121-36131, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32557025

RESUMO

The European roe deer (Capreolus capreolus) is one of the most abundant ungulate species in Europe. Many studies have investigated its distribution, behavior, and ecology, but few have focused on its role as bioindicators for pollutants, particularly regarding antlers, which has been shown to indicate also deer physiology. The presence of geothermal power plants can induce accumulation of potentially polluting elements (such as Tl, S, and Pb). Thus, we collected roe deer samples from areas of Tuscany (Italy) where power plants are present. They were divided according to whether their home range included areas close or far from geothermal power plants. We analyzed the body measurements and the profile of the minerals in the liver and antlers tissues using the ICP-OES technique. Results showed that livers from roe deer close to power plant accumulated higher quantity of Bi, Co, Ni, Tl, and S compared to controls. Males culled close to geothermal power plants had significantly lower values for weight and chest circumference, and also, the antlers showed higher values for Li and Sr in the first sampling position. Thus, despite the small sample size in this preliminary study, antlers and livers of roe deer seem to be a bioindicator of industrial impact on the environment.


Assuntos
Cervos , Animais , Osso e Ossos , Biomarcadores Ambientais , Europa (Continente) , Itália , Masculino , Minerais , Centrais Elétricas , Dados Preliminares
14.
Ecotoxicol Environ Saf ; 202: 110888, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32585485

RESUMO

Road dust from coal utilization is a significant source contributing to the generation of pollutants that can affect the health of people residing within close proximity to roadways. In this study, road dust samples were collected from different directions centered around a coal-fired power plant in Huainan. Black carbon (BC), soot, char, organic carbon (OC) and total carbon (TC), as well as the δ13C of samples, were determined. Compared to the reference locations which were distant from the power plant, the research areas surrounding the power plant were featured by significantly higher OC/BC ratio and TC concentration. The OC/BC showed significant difference in urban vs. rural areas, and at different distances from the central power plant, which implied that the source and spread of carbonaceous species was dominantly affected by wind direction and urban/rural area differences. Surface morphology analysis showed that the road dust was mixed with spherical particles similar to fly ash. High-resolution XPS C1s spectrum revealed the existence of metal carbide, metal carbonate, and CF3 in the road dust samples. The speciation of carbon in road dusts was found correlated with sampling directions and urban functional areas. Based on the δ13C and OC/BC, it could be inferred that coal-related substances might be important sources of road dusts.


Assuntos
Poluentes Atmosféricos/análise , Carvão Mineral/análise , Monitoramento Ambiental , Centrais Elétricas , Carbono/análise , Isótopos de Carbono/análise , China , Cinza de Carvão/análise , Poeira/análise , Fuligem/análise , Vento
15.
J Environ Radioact ; 218: 106261, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32421581

RESUMO

Tritium is a radionuclide commonly observed worldwide in riverine systems. In the Rhône River downstream the Lake Geneva (Switzerland and France), its occurrence is also related to its use for its luminescent properties in watchmaking paints. In fact, tritium is regularly observed at anomalous levels in this river and extreme events such as flushing operations might conduct to its transport downstream. In the Rhône River, characterized by 21 dams downstream the Geneva Lake, such operations are regularly organized to remove the sediments and limit problematic consequences such as siltation and increased flooding hazards. The consequences of dam flushing operations on tritium concentrations were thus investigated. Samples of Suspended Particulate Matter (SPM) and water were collected in the Rhone River downstream of Geneva in June 2012, during a planned flushing operation of three upstream reservoirs (Verbois, Chancy-Pougny and Génissiat). The concentrations of tritiated water (HTO) and organically bound Tritium (OBT) were measured and compared to reference concentrations. The flushing operations had no impact on the HTO concentration while the increases observed were related to the authorized releases of HTO from a nuclear power plant located downstream the dams. High increases of OBT concentrations in SPM were observed at two stations (Creys-Malville and Jons) without clear spatial or temporal trends. These anomalous peaks could be explained by the heterogeneous spatial distribution of technogenic tritium leading to large variations of tritium concentrations within the samples even though collected in areas close to each other. The results highlight the need to investigate the amount of such technogenic tritium currently stored in the upstream Rhone River as it might be significant.


Assuntos
Monitoramento de Radiação , Trítio/análise , Poluentes Radioativos da Água/análise , França , Centrais Elétricas , Rios , Suíça
16.
Chemosphere ; 253: 126714, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464776

RESUMO

Nowadays, the solid waste produced from palm oil has become one of the essential oils in the world in general and especially in Indonesia. Biomass waste is processed through substantial quantities of palm oil extraction. With the reduction in fossil fuels in recent years, it has had an impact on the deterioration of electricity supply at the National and International levels. Biomass is a renewable energy that can replace conventional energy. Besides, power generation from biomass is environmentally friendly and sustainable. This simulation was conducted to analyze the maximum power from the burning of oil palm biomass for the electricity generation. The novelty of the article is the performance and behavior of palm oil biomass-based co-fuel in the power generation process. The biomass wastes used in this simulation include OPF, EFB, PKS, and OPM. The results of this simulation indicate that the maximum power produced with OPF can produce 49.54 MW with variations in the flow rate of biomass at 8 kg/s. While at the time of recycling up to 100% OPM biomass produces 61.05 MW higher than OPF, EFB and PKS. Meanwhile, the OPF-PKS mixed biomass can produce 106.15 MW of power plants when the airflow rate reaches 171 kg/s. The overall results of the simulation for the analysis of the maximum power that can be used as a power station show suitability and can apply in rural/remote areas. Besides, the availability of oil palm biomass in Aceh Province is also sufficient to overcome electricity shortages and reduce dependence on conventional energy.


Assuntos
Óleo de Palmeira , Centrais Elétricas , Resíduos Sólidos , Biomassa , Eletricidade , Combustíveis Fósseis , Indonésia
17.
PLoS One ; 15(5): e0229452, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32357150

RESUMO

Most of South Africa's energy is derived from the combustion of coal in pulverized coal-fired power plants (CFPP). However, when compared with the rest of the world, limited information regarding the main radioactive elements (U and Th) and specific radionuclides of interest (K40, Ra226 and Th232) from South African CFPP is available in the public domain. This paper aims to quantify the U, Th and specific radionuclides found in the coal used in selected South African CFPP in comparison to world averages found in literature. The U and Th concentrations were obtained by ICP-MS. The main radionuclides, K40, Ra226 and Th238, were quantified using gamma spectrometry. The U concentration and Th concentrations for the coal used in all the power plants was above the world average of 1.9 mg/kg and 3.2 mg/kg respectively. The coals with the highest Th content originated from the Mpumalanga power plant, while the U content in the Freestate power plant samples was the highest of the three. The concentrations of the K40 were between 88.43±10.75-110.76±8.92 Bq/kg, which are in-line with world averages of 4-785 Bq/kg. Similarly, the Ra226 and Th232 values were between 21.69±2.83-52.63±4.04 Bq/kg and 19.91±1.24-22.97±1.75 Bq/kg respectively, which are also in line with the world averages of 1-206 Bq/kg and 1-170 Bq/kg respectively. Radiological hazard indices such as radium equivalent (Raeq); external hazard index (Hex) and internal hazard index (Hin), that were estimated from these average radionuclide concentrations were less than the prescribed values found in literature. This indicated that no significant health risk was posed by the coal being used from these coal fields.


Assuntos
Carvão Mineral/análise , Centrais Elétricas , Poluentes Radioativos do Solo/isolamento & purificação , Cinza de Carvão/análise , Humanos , Doses de Radiação , Monitoramento de Radiação , Radioisótopos/química , Radioisótopos/isolamento & purificação , Rádio (Elemento)/química , Rádio (Elemento)/isolamento & purificação , Poluentes Radioativos do Solo/química , África do Sul , Espectrometria gama , Tório/química , Tório/isolamento & purificação , Urânio/química , Urânio/isolamento & purificação
18.
Bull Environ Contam Toxicol ; 105(1): 67-75, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32409854

RESUMO

Hydropower plants (HPPs) can affect the hydrological regime. However, biochemical responses of aquatic animals for the evaluation of this disturbing are not applied yet. The specimens of Unio tumidus were sampled in a reservoir (R) of a small HPP as well as downstream from the dam (DS). Biochemical indexes in the digestive gland and alkali labile phosphates (ALP) in the gonads were examined. The R-mollusks showed low cholinesterase, catalase and caspase-3 activities, and metallothionein concentration, but elevated levels of zinc and copper, oxidized glutathione and protein carbonyls. Concentrations of lactate, pyruvate and ALP, activity of superoxide dismutase and glutathione S-transferase, and lipid peroxidation level were similar in both groups. Integrated biomarker response (IBR/n) index (n = 13) was 2.17 and 0.29 in the R- and DS-groups correspondingly. We suggest that using integrative biological response based on the biochemical markers of bivalve mollusks can be a valid early warning step in assessing 'environmental flow' impact.


Assuntos
Monitoramento Ambiental , Centrais Elétricas , Unio/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Metalotioneína/metabolismo , Moluscos/metabolismo , Rios , Ucrânia , Unio/metabolismo , Poluentes Químicos da Água/análise
19.
Chemosphere ; 251: 126561, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443240

RESUMO

In this study, low-temperature catalytic NO oxidation with H2O2 over Na- and H-exchanged Y and ZSM-5 zeolites was investigated at 140 °C which is the average exhaust temperature of coal-fired power plant. Fast catalytic NO oxidation rates were observed over H-zeolites, and catalytic activity was proportional to the amount of Brønsted acid sites. HZSM-5 and HY zeolites show 65% and 95% NO removal efficiency, respectively, but the catalytic stability of HY was lower than HZM-5 due to partial dealumination during the reaction. In-situ DRIFTS analysis showed that NO+ species coordinated at framework sites played a direct role in the catalytic NO oxidation. Moreover, the possible reaction pathway was proposed to elucidate the mechanism of NO oxidation with H2O2 catalyzed over Brønsted acid sites. The effect of reaction temperature, H2O2 concentration, H2O2 flow and SO2 concentration on NO oxidation were investigated over H-zeolites. The experimental results indicated that the NO removal efficiency was increased with the increase of H2O2 concentration, but decreased with the increase of SO2 concentration. The NO removal efficiency first increased and then decreased with the increase of H2O2 flow and reaction temperature.


Assuntos
Poluentes Atmosféricos/análise , Peróxido de Hidrogênio/química , Óxidos de Nitrogênio/análise , Zeolitas/química , Ácidos/química , Poluentes Atmosféricos/química , Catálise , Temperatura Baixa , Modelos Teóricos , Óxidos de Nitrogênio/química , Oxirredução , Centrais Elétricas
20.
J Environ Sci (China) ; 92: 95-105, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32430136

RESUMO

Particulate matter emissions from ammonia-based wet flue gas desulfurization (Ammonia-WFGD) systems are composed of a filterable particulate matter and a condensable particulate matter (CPM) portion. However, the CPM part has been ignored for a long time, which results in an underestimation of the aerosol problems caused by Ammonia-WFGD systems. In our research, the characteristics of the CPM that emits from an Ammonia-WFGD system are investigated experimentally for the first time, with the US Environmental Protection Agency Method 202 employed as the primary measurement. The influences of some essential desulfurizing parameters are evaluated based on the experimental data. The results show that CPM contributes about 68.8% to the total particulate matter emission. CPM consists mainly of ammonium sulfates/sulfites, with the organic part accounting for less than 4%. CPM is mostly in the submicron fraction, about 71.1% of which originates from the NH3-H2O-SO2 reactions. The appropriate adjustments for the parameters of the flue gas and the desulfurizing solution can inhibit CPM formation to different extents. This indicates that the parameter optimizations are promising in solving CPM emission problems in Ammonia-WFGD systems, in which the pH adjustment alone can abate CPM emission by around 49%. The opposite variations of the parameters need attention because they can cause tremendous CPM emission increase.


Assuntos
Poluentes Atmosféricos/análise , Material Particulado/análise , Amônia , Carvão Mineral , Centrais Elétricas
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