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Predictable pollution: An assessment of weather balloons and associated impacts on the marine environment – An example for the Great Barrier Reef, Australia
2014
O’Shea, Owen R. | Hamann, Mark | Smith, Walter | Taylor, Heidi
Efforts to curb pollution in the marine environment are covered by national and international legislation, yet weather balloons are released into the environment with no salvage agenda. Here, we assess impacts associated with weather balloons in the Great Barrier Reef World Heritage Area (GBRWHA). We use modeling to assess the probability of ocean endpoints for released weather balloons and predict pathways post-release. In addition, we use 21months of data from beach cleanup events to validate our results and assess the abundance and frequency of weather balloon fragments in the GBRWHA. We found between 65% and 70% of balloons land in the ocean and ocean currents largely determine final endpoints. Beach cleanup data revealed 2460 weather balloon fragments were recovered from 24 sites within the GBRWHA. This is the first attempt to quantify this problem and these data will add support to a much-needed mitigation strategy for weather balloon waste.
显示更多 [+] 显示较少 [-]Real time observation system for monitoring environmental impact on marine ecosystems from oil drilling operations
2014
Godø, Olav Rune | Klungsøyr, Jarle | Meier, Sonnich | Tenningen, Eirik | Purser, Autun | Thomsen, Laurenz
Environmental awareness and technological advances has spurred development of new monitoring solutions for the petroleum industry.This paper presents experience from a monitoring program off Norway. To maintain operation within the limits of the government regulations Statoil tested a new monitoring concept. Multisensory data were cabled to surface buoys and transmitted to land via wireless communication. The system collected information about distribution of the drilling wastes and the welfare of the corals in relation to threshold values.The project experienced a series of failures, but the backup monitoring provided information to fulfil the requirements of the permit. The experience demonstrated the need for real time monitoring and how such systems enhance understanding of impacts on marine organisms. Also, drilling operations may improve by taking environmental information into account. The paper proposes to standardize and streamline monitoring protocols to maintain comparability during all phases of the operation and between drill sites.
显示更多 [+] 显示较少 [-]Spatial distribution of organic and pyritic sulfur in surface sediments of eutrophic Jiaozhou Bay, China: Clues to anthropogenic impacts
2014
Chen, Ke-Ke | Zhu, Mao-Xu | Yang, Gui-Peng | Fan, De-Jiang | Huang, Xiang-Li
Anthropogenic perturbations exert important impacts on sulfur geochemistry in marine sediments. In the study, chemical extraction was used to quantify four sulfur pools, i.e., pyrite, humic-acid sulfur (HA-S), fulvic-acid sulfur (FA-S), and residual organic sulfur (ROS), in surface sediments of eutrophic Jiaozhou Bay. Results show that riverine inputs are the main control on organic matter (OM) distribution in the sediments. OM enrichment in the eastern coast is mainly due to discharges of anthropogenic wastes. Spatial coupling of pyrite and FA-S vs. TOC points to the impacts of OM enrichment on formation and preservation of pyrite and FA-S. Poor spatial coupling of HA-S vs. TOC is due to low fractions of diagenetic OS in the pool. ROS is mainly from riverine inputs and anthropogenic OS has been superimposed on this pool. Spatial coupling among TOC, pyrite-S and FA-S is a sensitive indicator of anthropogenic impacts on benthic processes of the bay.
显示更多 [+] 显示较少 [-]Evaluation of airborne Actinomycetes at waste application facilities
2014
Awad, Abdel Hameed | El Gendy, Safa A.
This study aimed to evaluate airborne meso–and–thermophilic actinomycete concentrations and their types at a wastewater treatment plant and a biosolid landfill, in Egypt. Air samples were collected at 200m upwind, and onsite and 300m downwind by using liquid impinger sampler, calibrated to draw 12.5L/min, for 20 minutes. The concentrations ranged between 0.0–7 360CFU/m3 for mesophilic, and 106–586CFU/m3 for thermophilic actinomycetes. Airborne actinomycete concentrations exceeded the suggested occupational exposure limit value of 100CFU/m3. No significant correlations were found between actinomycete concentrations onsite and 300m downwind distance. At the biosolid landfill, upwind thermophilic actinomycetes significantly differed (p<0.05) from onsite and 300m downwind. A total of 40 and 69 airborne actinomycete isolates belonging to 8 genera were identified at the wastewater treatment plant and biosolid landfill. Streptomyces were the dominant actinomycete species. Streptomyces diastaticus, Pseudonocardia compacta and Catellatospora ferruginea were only detected at the biosolid landfill site. Meso–and–thermophilic actinomycetes positively associated with relative humidity, and wind speed positively correlated with onsite thermophilic actinomycetes (r=0.65) at the biosolid landfill. Temperature showed negative effect on survivability of mesophilic actinomycetes (r=-0.8) onsite of the wastewater treatment plant. Waste application facilities increase actinomycete concentrations onsite which may consequently deteriorate air quality in the nearby areas.
显示更多 [+] 显示较少 [-]National inventory of mercury release into different phase media estimated by UNEP Toolkit in South Korea
2014
Pudasainee, Deepak | Seo, Yong-Chil | Kim, David Junghoon | Hong, Ji-Hyung | Park, Jung-Min
This paper summarizes the national inventory of mercury release into all media (air, water, land, impurity in products, general wastes and sector specific disposal) from South Korea, using UNEP mercury Toolkit. Total mercury input and release, distribution into different media, major contributors by source categories are discussed. The total quantified mercury release into different phase media was 284.0 t/y and 281.3 t/y in Level 1 and 2 estimation, respectively. Mercury release from primary metal production, waste incineration, extraction and use of fuels/energy sources were dominant. The replacement of output distribution factors in the Toolkit by real data from mass balance study in the anthropogenic sources resulted decrease in the share of mercury emission into air from 20.6% to 9.6%. Comparison of mercury releases into the atmosphere estimated by the Toolkit Level 2 with real distribution factors data and our earlier estimation with measurements in the selected industries showed only a little discrepancy, with reasonable variation. These differences are due to the use of efficient process technology and air pollution control devices. Since most mercury is released in waste and byproducts, recovery and safe storage issues are to be emphasized in the future studies.
显示更多 [+] 显示较少 [-]Citric Acid-Assisted Phytoextraction of Lead in the Field: The Use of Soil Amendments
2014
Freitas, Eriberto Vagner | Nascimento, Clístenes Williams | Silva, Wildson Morais
The increased industrial and economic developments that have occurred in recent decades, particularly in mining, agricultural and metal recycling activities have decisively contributed to the increased concentration of heavy metals in soil. This study was carried out to evaluate the performance of Sorghum bicolor and Chrysopogon zizanioides in the citric acid-assisted phytoextraction of Pb in a field experiment setup in an area contaminated by automotive battery waste. Two soils amendments were used and they were dolomitic limestone and silicate slag at doses of 4.74 and 12.80 t ha⁻¹, respectively. Commercial citric acid was applied in each experimental parcel on the 63rd day of the cultivation in order to enhance Pb solubilisation and plant availability. Citric acid, which was applied at a dose of 40 mmol kg⁻¹of soil, was efficient in the solubilisation of Pb in soil and in the induction assisting of the removal of Pb from soil by the both species tested. Commercial citric acid is indicated for use in the area, due to its low cost and high biodegradability. Due to the low natural solubility of Pb and the large amount of time required, i.e. more than 900 years, phytoextraction without the application of chelating agents is not viable for remediation of the study area. Sorghum grown in soil amended with silicate slag combined with the application of the chelating agent commercial citric acid is the recommended phytoextraction programme for the remediation of an area with moderate Pb contamination.
显示更多 [+] 显示较少 [-]Photocatalytic Properties of Silver Incorporated Titania Nanoparticles Immobilized on Waste-Derived Polystyrene
2014
Altın, İlknur | Sökmen, Münevver
Silver-doped TiO₂(Ag-TiO₂) immobilized onto polystyrene (PS) waste was prepared using a thermal attachment method. Its efficiencies as a photocatalyst under UVA light (λ = 365 nm) for the removal of Cr(VI), methylene blue, Escherichia coli, and Aspergillus niger from water were studied. The results showed that Ag-TiO₂-PS material removes pollutants at significantly high rates and especially posseses strong disinfection properties. The morphological study of Ag-TiO₂-PS material was carried out using X-ray diffraction, scanning electron microscope, and energy dispersive X-ray spectroscopy. The catalyst can be prepared using waste PS employing a simple immobilization method and it is highly effective for the removal of biological and chemical impurities from drinking and underground water supplies.
显示更多 [+] 显示较少 [-]Modeling the Odor Generation in WWTP: An Integrated Approach Review
2014
Carrera-Chapela, Fabio | Donoso-Bravo, Andres | Souto, José A. | Ruiz-Filippi, Gonzalo
Nuisance odors generation from waste and wastewater treatment plants are a cause of public discomfort and complaints. This situation impairs the air quality and represents a growing social and public health problem, especially in developing countries. Several modeling approaches have been developed and successfully implemented in the frame of a wastewater treatment plant for both the biological treatment and physicochemical processes. The mathematical modeling of the odor generation process is still considered a quite complex issue, mainly due to the fact that olfactory nuisance can be caused by many different chemical compounds and the perception of odors is influenced by subjective thresholds. Moreover, the impact of odor sources on air quality is highly conditioned by complex atmospheric dispersion processes. This review presents a critical state-of-art and assessment where information related to odor emissions impact studies as well as modeling applications are compiled and discussed.
显示更多 [+] 显示较少 [-]Spent Potassium Silicate Drilling Fluid Affects Soil and Leachate Properties
2014
Yao, Linjun | Naeth, M Anne | Chanasyk, David S.
Potassium silicate drilling fluid (PSDF) is a relatively new type of drilling waste generated by the oil and gas industry. PSDF effects on soil, vegetation, and ground water must be determined before its land disposal and use in reclamation can be regulated. A laboratory column leachate study was conducted to quantify the response of select soil and leachate properties to PSDF at various depths in soil column profiles. A spent PSDF was applied to two soils (sand and loam textures) at four rates (20, 40, 60, 120 m³ ha⁻¹) with two application methods (incorporated, sprayed). Changes to soil and leachate properties were at values that would not be detrimental to most plant species when PSDF was applied at ≤60 m³ ha⁻¹. Applying PSDF at 120 m³ ha⁻¹had significant effects on soil properties and leachate quality. Hydraulic conductivity and field capacity were significantly reduced, and soil available potassium and sulfate concentrations, pH, and salinity increased with PSDF. Incorporated PSDF in the upper 10 cm of soil accelerated PSDF element transport through soil columns to leachate and increased organic carbon and salinity in leachate. PSDF application rate significantly reduced soil field capacity, available nitrogen, and increased salinity at the highest rates in loam soil, suggesting a threshold beyond which conditions will not be suitable for land spraying PSDF. This research demonstrates that PSDF has potential to improve soil short term water availability, macronutrient potassium and sulfur for disposal on cultivated and uncultivated lands. This potential should be field tested.
显示更多 [+] 显示较少 [-]Removal of Remazol Brilliant Blue R From Aqueous Solution by Pirina Pretreated with Nitric Acid and Commercial Activated Carbon
2014
Dağdelen, Sevgi | Acemioğlu, Bilal | Baran, Evrim | Koçer, Oğuzhan
Pirina, a waste of olive oil factory, was used as an adsorbent for the removal of remazol brilliant blue R (RBBR) from aqueous solution by adsorption process. The pirina was pretreated with HNO₃before batch adsorption experiments. The effects of contact time, initial concentration, pH, temperature, and ionic strength on dye removal were investigated. While the amount of the dye removed by the pirina was increasing with increasing initial concentration and temperature, it decreased with an increase in pH. Moreover, commercial activated carbon (CAC) was also used to compare with the pirina in removing the RBBR. The maximum amounts of the RBBR removed by the pirina and the CAC were 23.63 and 199.45 mg g⁻¹per unit mass of the adsorbents, and the removal efficiencies of them were found as 94.52 and 99.72 %, respectively. Ionic strength in the presence of NaCl and KCl had also a reducing effect on the removal efficiency. The adsorption isotherm was in the best harmony with Langmuir, Freundlich, and Temkin models. The adsorption kinetic obeyed the pseudo-second-order and the intra-particle diffusion models. The values of the r²from the pseudo-second-order kinetic and intra-particle diffusion were between 0.984–0.999 and 0.85–0.996, respectively. From thermodynamic studies, it was seen that the adsorption was of spontaneous and endothermic nature. The values of ΔG° of the adsorption were between −3,218 and −8,867 J mol⁻¹. The values of ΔH° and ΔS° were 50,134 J mol⁻¹and 179 J mol⁻¹ K⁻¹, respectively. Moreover, SEM and FT-IR studies were also performed.
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