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Sample records for dry ashing

  1. FLY ASH RECYCLE IN DRY SCRUBBING

    Science.gov (United States)

    The paper describes the effects of fly ash recycle in dry scrubbing. (Previous workers have shown that the recycle of product solids improves the utilization of slaked lime--Ca(OH)2--for sulfur dioxide (SO2) removal by spray dryers with bag filters.) In laboratory-scale experimen...

  2. Bottom ash handling: why the outlook is dry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-03-15

    The author believes that dry systems are the way forward for bottom ash handling at coal fired power plants. The first two commercial installations of Clyde Bergemann's DRYCON system, in China, are due to enter operation shortly. The DRY ash CONveyor (DRYCON) employs fresh air flow to cool the ash, returning reheat energy to the boiler. It also addresses some problems encountered with previous dry technologies whilst increasing ash capacity and enhancing ash cooking. The advantages of the DRYCON over the wet submerged scraper conveyor are listed. 7 figs.

  3. Drycon dry ash conveyor: dry bottom ash handling system with reduced operating costs and improved plant efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The Drycon dry bottom ash extraction system is designed to remove bottom ash beneath the furnace, cooling it without any need of water. Fresh air in countercurrent flow to the ash is used for the ash cooling. Data presented show how savings of time and costs can be achieved with this system and how a boiler efficiency can be increased using this technology. Considerable advantages in the reliability of operation with new improvements of the design are described. 7 figs.

  4. The use of shale ash in dry mix construction materials

    Science.gov (United States)

    Gulbe, L.; Setina, J.; Juhnevica, I.

    2017-10-01

    The research was made to determine the use of shale ash usage in dry mix construction materials by replacing part of cement amount. Cement mortar ZM produced by SIA Sakret and two types of shale ashes from Narva Power plant (cyclone ash and electrostatic precipitator ash) were used. Fresh mortar properties, hardened mortar bulk density, thermal conductivity (λ10, dry) (table value) were tested in mortar ZM samples and mortar samples in which 20% of the amount of cement was replaced by ash. Compressive strenght, frost resistance and resistance to sulphate salt solutions were checked. It was stated that the use of electrostatic precipitator ash had a little change of the material properties, but the cyclone ash significantly reduced the mechanical strength of the material.

  5. [Conversion methods of freshwater snail tissue dry mass and ash free dry mass].

    Science.gov (United States)

    Zhao, Wei-Hua; Wang, Hai-Jun; Wang, Hong-Zhu; Liu, Xue-Qin

    2009-06-01

    Mollusk biomass is usually expressed as wet mass with shell, but this expression fails to represent real biomass due to the high calcium carbonate content in shells. Tissue dry mass and ash free dry mass are relatively close to real biomass. However, the determination process of these two parameters is very complicated, and thus, it is necessary to establish simple and practical conversion methods for these two parameters. A total of six taxa of freshwater snails (Bellamya sp., Alocinma longicornis, Parafossarulus striatulus, Parafossarulus eximius, Semisulcospira cancellata, and Radix sp.) common in the Yangtze Basin were selected to explore the relations of their five shell dimension parameters, dry and wet mass with shells with their tissue dry mass and ash free dry mass. The regressions of the tissue dry mass and ash free dry mass with the five shell dimension parameters were all exponential (y = ax(b)). Among them, shell width and shell length were more precise (the average percentage error between observed and predicted value being 22.0% and 22.5%, respectively) than the other three parameters in the conversion of dry mass. Wet mass with shell could be directly converted to tissue dry mass and ash free dry mass, with an average percentage error of 21.7%. According to the essence of definition and the errors of conversion, ash free dry mass would be the optimum parameter to express snail biomass.

  6. Study of a large rapid ashing apparatus and a rapid dry ashing method for biological samples and its application

    International Nuclear Information System (INIS)

    Jin Meisun; Wang Benli; Liu Wencang

    1988-04-01

    A large rapid-dry-ashing apparatus and a rapid ashing method for biological samples are described. The apparatus consists of specially made ashing furnace, gas supply system and temperature-programming control cabinet. The following adventages have been showed by ashing experiment with the above apparatus: (1) high speed of ashing and saving of electric energy; (2) The apparatus can ash a large amount of samples at a time; (3) The ashed sample is pure white (or spotless), loose and easily soluble with few content of residual char; (4) The fresh sample can also be ashed directly. The apparatus is suitable for ashing a large amount of the environmental samples containing low level radioactivity trace elements and the medical, food and agricultural research samples

  7. Losses of the elements during dry ashing of plant materials

    International Nuclear Information System (INIS)

    Nonaka, Nobuhiro; Higuchi, Hideo; Hamaguchi, Hiroshi; Tomura, Kenji.

    1981-01-01

    Dry ashing technique has been considered to cause potential errors due to loss of elements by volatilisation or by reaction with the vessel. To obtain an overall view of elemental loss, the dry ashing was applied to the standard reference materials such as Orchard leaves(NBS) and Bamboo leaves. The ashing condition was as follows; The temperature varied from 200 0 C to 800 0 C by stepwise heating and the duration of heating at each temperature was 24 h. Concentrations of 25 elements in a sample were determined by means of atomic absorption spectrometry and neutron activation analysis using a Ge(Li) detector. The results obtained were as follows; (1) The losses for alkali elements were dependent on crucible materials and sample species. The losses increased with temperature and they were serious when a silica dish was used. (2) The loss for mercury was found above 110 0 C and simply increased with temperature. On the other hand, chlorine, bromine, selenium and chromium showed complicated patterns in which the first losses occurred at 200 0 C, no additional losses being observed at each following step of heating between 200 0 C and 450 0 C, and they increased again above 500 0 C. (3) The losses for arsenic and antimony occurred at 200 0 C, but any losses could not be observed above 200 0 C. (4) No losses were detected over the temperature range studied for alkaline earths, rare earths, vanadium, manganese, iron, cobalt, zinc and aluminum. (author)

  8. Failure to phytosanitize ash firewood infested with emerald ash borer in a small dry kiln using ISPM-15 standards.

    Science.gov (United States)

    Goebel, P Charles; Bumgardner, Matthew S; Herms, Daniel A; Sabula, Andrew

    2010-06-01

    Although current USDA-APHIS standards suggest that a core temperature of 71.1 degrees C (160 degrees F) for 75 min is needed to adequately sanitize emerald ash borer, Agrilus planipennis Fairmaire-infested firewood, it is unclear whether more moderate (and economical) treatment regimes will adequately eradicate emerald ash borer larvae and prepupae from ash firewood. We constructed a small dry kiln in an effort to emulate the type of technology a small- to medium-sized firewood producer might use to examine whether treatments with lower temperature and time regimes successfully eliminate emerald ash borer from both spilt and roundwood firewood. Using white ash (Fraxinus americana L.) firewood collected from a stand with a heavy infestation of emerald ash borer in Delaware, OH, we treated the firewood using the following temperature and time regime: 46 degrees C (114.8 degrees F) for 30 min, 46 degrees C (114.8 degrees F) for 60 min, 56 degrees C (132.8 degrees F) for 30 min, and 56 degrees C (132.8 degrees F) for 60 min. Temperatures were recorded for the outer 2.54-cm (1-in.) of firewood. After treatment, all firewood was placed under mesh netting and emerald ash borer were allowed to develop and emerge under natural conditions. No treatments seemed to be successful at eliminating emerald ash borer larvae and perpupae as all treatments (including two nontreated controls) experienced some emerald ash borer emergence. However, the 56 degrees C (132.8 degrees F) treatments did result in considerably less emerald ash borer emergence than the 46 degrees C (114.8 degrees F) treatments. Further investigation is needed to determine whether longer exposure to the higher temperature (56 degrees C) will successfully sanitize emerald ash borer-infested firewood.

  9. Wet vs dry bottom ash handling compared: one plant's experience

    Energy Technology Data Exchange (ETDEWEB)

    Cianci, V. [Magaldi R & D, Salerno (Italy)

    2007-06-15

    A multi-unit coal-fired power station where both dry and wet bottom ash handling systems are employed provides an opportunity for detailed comparison of the two approaches. The study reported in the article was carried out at a plant which has four 314 MWe coal fired units. It was designed for baseload operation and the wet system, coexisting with the dry Magaldi Ash Cooler (MAC) system has high dependability. The design is in fact a hybrid of water impounded hopper system and a submerged chain conveyor (SCC) system for both bottom ash and pyrites handling. Dry ash technology was introduced in 2004. The dry system resulted in water saving of about 258,000 m{sup 3} per year. It also reduces ash disposal costs and increases boiler efficiency due to recovery of much of the heat leaving the boiler. A net thermal power saving of 1316 KWt per MAC system is made. The study also showed that the Superbelt (a steel mesh belt conveyor coupled with overlapping steel plates) applied to dry ash conveying, as in the MAC system, is much more dependable than a chain conveying system, for both wet and dry systems. By 2008 all four units of the plant will be replaced with dry MAC systems. 9 figs., 2 tabs.

  10. Influence of ash on the fiber composition of dried dairy manures

    International Nuclear Information System (INIS)

    Reeves, J.B.; Van Kessel, J.A.S.

    2002-01-01

    The ash content of dried dairy manures is a significant source of error in the determination of their fiber composition. - The objective of this work was to examine the role of ash in the compositional analysis of dried dairy manures. Ninety-nine dairy manures obtained from Connecticut, Maryland, New York, Pennsylvania and Virginia were dried at 60 deg. C, and ground to 20 mesh. Samples were analyzed for neutral and acid detergent fiber, acid detergent lignin, total carbon, total nitrogen, and ash. In addition, cellulose and hemicellulose were computed by difference. Results indicated that high ash contents (8-52% of dry matter) can dramatically and unpredictably alter various measures of fiber composition and are a significant source of error in the determination of manure composition and how it relates to mineralization or other compositional influenced factors. Also, while the ash content of the dried intact manure can easily be determined, it is difficult to estimate the ash contribution to the individual fiber determinations, especially if sequential assays are performed

  11. Rainfall and wet and dry cycle's impact on ash thickness. A laboratory experiment

    Science.gov (United States)

    Pereira, Paulo; Keestra, Saskia; Peters, Piet; Cerdà, Artemi

    2016-04-01

    Ash is the most important and effective soil protection in the immediate period after the fire (Cerda and Doerr, 2008; Pereira et al., 2015a). This protection can last for days or weeks depending on the fire severity, topography of the burned area and post-fire meteorological conditions. In the initial period after the fire, ash is easily transported by wind. However after the first rainfalls, ash is eroded, or bind in soil surface (Pereira et al., 2013, 2015a). Ash thickness has implications on soil protection. The soil protection against the erosion and the ash capacity to retain water increases with the ash thickness (Bodi et al., 2014). Ash cover is very important after fire because store water and releases into soil a large amount of nutrients, fundamental to vegetation recuperation (Pereira et al., 2014). Despite the importance of ash thickness in post fire environments, little information is available about the effects of rainfall and wet and dry cycle's effects on ash thickness. This work aims to fill this gap. The objective of this study is to investigate the impacts of rainfall and wet and dry cycles in the ash thickness of two different under laboratory conditions. Litter from Oak (Quercus robur) and Spruce (Picea abis) were collected to and exposed during 2 hours to produce ash at 200 and 400 C. Subsequently a layer of 15 mm ash was spread on soil surface in small boxes (24x32 cm) and then subjected to rainfall simulation. Boxes were placed at a 17% of inclination and a rainfall intensity of 55 mm/h during 40 minutes was applied. After the rainfall simulation the plots were stored in an Oven at the temperature of 25 C during four days, in order to identify the effects of wet and dry cycles (Bodi et al., 2013). Ash thickness was measured after the first rainfall (AFR), before the second rainfall (BSR) - after the dry period of 4 days - and after the second rainfall (ASR). In each box a grid with 57 points was designed in order to analyse ash thickness

  12. Dry Sliding Friction and Wear Studies of Fly Ash Reinforced AA-6351 Metal Matrix Composites

    Directory of Open Access Journals (Sweden)

    M. Uthayakumar

    2013-01-01

    Full Text Available Fly ash particles are potentially used in metal matrix composites due to their low cost, low density, and availability in large quantities as waste by-products in thermal power plants. This study describes multifactor-based experiments that were applied to research and investigation on dry sliding wear system of stir-cast aluminum alloy 6351 with 5, 10, and 15 wt.% fly ash reinforced metal matrix composites (MMCs. The effects of parameters such as load, sliding speed, and percentage of fly ash on the sliding wear, specific wear rate, and friction coefficient were analyzed using Grey relational analysis on a pin-on-disc machine. Analysis of variance (ANOVA was also employed to investigate which design parameters significantly affect the wear behavior of the composite. The results showed that the applied load exerted the greatest effect on the dry sliding wear followed by the sliding velocity.

  13. Wet-dry cycles effect on ash water repellency. A laboratory experiment.

    Science.gov (United States)

    Pereira, Paulo; Cerdà, Artemi; Oliva, Marc; Mataix, Jorge; Jordán, Antonio

    2014-05-01

    In the immediate period after the fire, the ash layer has a strong influence on soil hydrological processes, as runoff, infiltration and erosion. Ash is very dynamic in the space and time. Until the first rainfall periods, ash is (re)distributed by the wind. After it can cover the soil surface, infiltrate or transported to other areas by water transport (Pereira et al., 2013a, b). This will have strong implications on nutrient redistribution and vegetation recovery. Ash layer may affect soil water repellency in different ways, depending on fire severity, soil properties and vegetation. Ash produced at low temperatures after low-severity burning is usually hydrophobic (Bodi et al., 2011, 2012). Wet-dry cycles have implications on ash physical and chemical properties, changing their effects in space and time. The aim of this study is to analyse the effects of fire temperature and severity on ash water repellency. Pinus sylvestris needles were collected in a Lithuania forest in Dzukija National Park (53º 54' N and 24º 22' E), transported to laboratory and washed with deionized water to remove soil particles and other residues. Needle samples were dried during 24 hours and exposed to different temperatures: 200, 300, 400 and 500 ºC, during 2 hours. Ash colour was analysed according to the Munsell Soil Color charts. Ash was black (10 YR 2/1) at 200 ºC, very dark grey (10YR 3/1) at 300 ºC, gray (10YR 5/1) at 400 ºC and light gray (10YR 7/1) at 500 ºC. Ten samples of ash released after each treatment were placed in plastic dishes (50 mm in diameter) in an amount enough to form a 5 mm thick layer, and ash water repellency was measured according to the Water Drop Penetration Test. Later, ash was carefully wetted with 15 ml of deionized water and placed in an oven during 4 days (96 hours), as in Bodí et al. (2012). This procedure was repeated 5 times in order to observe the effects of wet-dry cycles in ash water repellency. The results showed significant differences

  14. Effect of bagasse ash reinforcement on dry sliding wear behaviour of polymer matrix composites

    International Nuclear Information System (INIS)

    Aigbodion, V.S.; Hassan, S.B.; Agunsoye, J.O.

    2012-01-01

    Highlights: → The influence of wear parameters on the wear rate of RLDPE were investigated. → The predicted wear rate of the RLDPE and it composites were found to lie close to that experimentally observed ones. → The results showed that the addition of bagasse ash as filler materials in RLDPE composites increase the wear resistance. -- Abstract: The tribological behaviour of recycled low density polyethylene (RLDPE) polymer composites with bagasse ash particles as a reinforcement was studied using a pin-on-disc wear rig under dry sliding conditions. The influence of wear parameters like, applied load, sliding speed, sliding distance and percentage of bagasse ash fillers, on the wear rate were investigated. A plan of experiments was performed to acquire data in a controlled way. Scanning electron microscope was used to analyse the worn surface of the samples. Linear regression equation and analysis of variance (ANOVA) were employed to investigate the influence of process parameters on the wear rate of the samples. The predicted wear rate of the RLDPE and it composites were found to lie close to that experimentally observed ones. The confirmation of the experiments conducted using ANOVA to verify the optimal testing parameters show that sliding speed and applied load had significant effect on the wear rate. The results showed that the addition of bagasse ash as filler materials in RLDPE composites increase the wear resistance of the composite greatly.

  15. Increased sensitivity in thick-target particle induced X-ray emission analyses using dry ashing for preconcentration

    International Nuclear Information System (INIS)

    Lill, J.-O.; Harju, L.; Saarela, K.-E.; Lindroos, A.; Heselius, S.-J.

    1999-01-01

    The sensitivity in thick-target particle induced X-ray emission (PIXE) analyses of biological materials can be enhanced by dry ashing. The gain depends mainly on the mass reduction factor and the composition of the residual ash. The enhancement factor was 7 for the certified reference material Pine Needles and the limits of detection (LODs) were below 0.2 μg/g for Zn, Cu, Rb and Sr. When ashing biological materials with low ash contents such as wood of pine or spruce (0.3% of dry weight) and honey (0.1% of wet weight) the gain was far greater. The LODs for these materials were 30 ng/g for wood and below 10 ng/g for honey. In addition, the ashed samples were more homogenous and more resistant to changes during the irradiation than the original biological samples. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  16. Natural weathering in dry disposed ash dump: Insight from chemical, mineralogical and geochemical analysis of fresh and unsaturated drilled cores.

    Science.gov (United States)

    Akinyemi, S A; Akinlua, A; Gitari, W M; Khuse, N; Eze, P; Akinyeye, R O; Petrik, L F

    2012-07-15

    Some existing alternative applications of coal fly ash such as cement manufacturing; road construction; landfill; and concrete and waste stabilisation use fresh ash directly collected from coal-fired power generating stations. Thus, if the rate of usage continues, the demand for fresh ash for various applications will exceed supply and use of weathered dry disposed ash will become necessary alternative. As a result it's imperative to understand the chemistry and pH behaviour of some metals inherent in dry disposed fly ash. The bulk chemical composition as determined by XRF analysis showed that SiO2, Al2O3 and Fe2O3 were the major oxides in fresh ash and unsaturated weathered ashes. The unsaturated weathered ashes are relatively depleted in CaO, Fe2O3, TiO2, SiO2, Na2O and P2O5 due to dissolution and hydrolysis caused by chemical interaction with ingressing CO2 from the atmosphere and infiltrating rain water. Observed accumulations of Fe2O3, TiO2, CaO, K2O, Na2O and SO3 and Zn, Zr, Sr, Pb, Ni, Cr and Co in the lower layers indicate progressive downward movement through the ash dump though at a slow rate. The bulk mineralogy of unsaturated weathered dry disposed ash, as determined by XRD analysis, revealed quartz and mullite as the major crystalline phases; while anorthite, hematite, enstatite, lime, calcite, and mica were present as minor mineral phases. Pore water chemistry revealed a low concentration of readily soluble metals in unsaturated weathered ashes in comparison with fresh ash, which shows high leachability. This suggests that over time the precipitation of transient minor secondary mineral phases; such as calcite and mica might retard residual metal release from unsaturated weathered ash. Chloride and sulphate species of the water soluble extracts of weathered ash are at equilibrium with Na+ and K+; these demonstrate progressive leaching over time and become supersaturated at the base of unsaturated weathered ash. This suggests that the ash dump does not

  17. Application of dry separative methods for decreasing content the residues unburned coal and separation Fe from black coal flies ash

    Directory of Open Access Journals (Sweden)

    František Kaľavský

    2008-06-01

    Full Text Available Main obstacle using of fly ashes in building, that is its main consumer, is the residue of unburned coal; it is expressed of loss onignition - LOI. In present, the valid STN and EU standard limits the content of LOI to 3 – 5 %, in national conditions maximum 7 %.Application of processing technologies also has to assure utilization of fly ash that provides a possibility of complex utilizationof individual products obtained by modification.By means of corona separation, based on different conductivity of individual fly ash elements, it is possible to separate unburnedcoal particles. The fly ash sample from black coal burning in melting boiler that was deposited on fly ash deposit, content of LOIof dielectric particle 6,45 % at 61 % weight yield was achieved. In the samples taken from dry taking of fly ash the non-conductingproduct contained 7,72 % of LOI at 73 % of weight yield.

  18. The determination of optimum condition in water hyacinth drying process by mixed adsorption drying method and modified fly ash as an adsorbent

    Science.gov (United States)

    Saputra, Asep Handaya; Putri, Rizky Anggreini

    2017-05-01

    Water hyacinth is an aquatic weed that has a very fast growth which makes it becomes a problem to the ecosystem. On the other hand, water hyacinth has a high fiber content (up to 20% by weight) which makes it potential to become raw material for composites and textile industries. As an aquatic plant, water hyacinth has a high initial moisture content that reaches more than 90%. Meanwhile the moisture content of fiber as a raw material for composite and textile industry should not be more than 10% to maintain the good quality of the products. Mixed adsorption drying method is one of the innovative method that can replace conventional drying process. Fluidization method which has been commonly used in agricultural and pharmaceutical products drying, can be enhanced by combining it with the adsorption method as performed in this study. In mixed fluidization-adsorption drying method, fly ash as adsorbent and water hyacinth fiber were put together into the fluidization column where the drying air evaporate the moisture content in water hyacinth fiber. In addition, the adsorbent adsorb the moisture content in the drying air to make the moisture content of the drying air remain low. The drying process is performed in various temperature and composition of water hyacinth and adsorbent in order to obtain the optimum drying condition. In addition, the effect of fly ash pellet and fly ash powder to the drying process was also performed. The result shows that the higher temperature and the more amount of adsorbent results in the faster drying rate. Fly ash pellet shows a better adsorption since it has a smaller pore diameter and wider surface area. The optimum temperature obtained from this study is 60°C and the optimum ratio of water hyacinth and fly ash is 50:50.

  19. THE VITAMIN VALUE OF FRUITS OF THE MOUNTAIN ASH AT DIFFERENT WAYS OF THEIR PRESERVATION AND DRYING

    Directory of Open Access Journals (Sweden)

    Vyacheslav Leonidovich Zakharov

    2016-02-01

    Full Text Available In scientific literature the structure there aren’t enough data on influence of ways of preservation of fruits of a mountain ash on their vitamin. As object of research fruits of grades of a mountain ash served. Fruits were analysed by chemical methods on the content of some vitamins, then preserved in the form of compotes, the mountain ash wiped with sugar and dried up. The product was sterilized at a different temperature. Conditions for the best safety of some vitamins are revealed.

  20. Determination of chromium in Bowen's kale, NBS bovine liver, and brewers yeast, before and after dry ashing

    International Nuclear Information System (INIS)

    Versieck, J.; Hoste, J.; De Rudder, J.; Barbier, F.; Vanballenberghe, L.

    1979-01-01

    In view of the persistent controversy about the volatility of chromium in biologic materials, the element was determined by neutron activation analysis in three reference materials before and after dry ashing up to 450 0 C. The following mean values were obtained: 0.364 μg/g and 0.362 μg/g (Bowen's kale), 0.0806 μg/g and 0.0789 μg/g (NBS bovine liver), 2.043 μg/g and 2.094 μg/g (NBS brewers yeast). It was concluded that chromium does not volatilize significantly in experimental conditions of drying and ashing

  1. Dry sliding behavior of aluminum alloy 8011 with 12% fly ash composites

    Science.gov (United States)

    Magibalan, S.; Senthilkumar, P.; Palanivelu, R.; Senthilkumar, C.; Shivasankaran, N.; Prabu, M.

    2018-05-01

    This research focused on the fabrication of aluminum alloy 8011 with 12% fly ash (FA) composite (AA8011%–12% FA) using the stir casting method. A three-level central composite design experiment was developed using response surface methodology with various parameters such as load, time, and sliding velocity varied in the range of 5 to 15 N, 5 to 15 min, and 1.5 to 4.5 m.s‑1, respectively. Dry sliding wear tests were performed as per the experimental design using a pin on disc at room temperature. The obtained regression result indicated that the developed model performed well in relating the wear process parameters and predicted the wear behavior of the composite. The surface plot showed that the wear rate increases with increase in load, time, and sliding velocity. Hardness was evaluated by Vickers hardness testing machine. Moreover, the surface morphology of the worn-out composite was examined using a scanning electron microscope.

  2. Drying Shrinkage Behaviour of Fibre Reinforced Concrete Incorporating Polyvinyl Alcohol Fibres and Fly Ash

    Directory of Open Access Journals (Sweden)

    Amin Noushini

    2014-01-01

    Full Text Available The current study assesses the drying shrinkage behaviour of polyvinyl alcohol fibre reinforced concrete (PVA-FRC containing short-length (6 mm and long-length (12 mm uncoated monofilament PVA fibres at 0.125%, 0.25%, 0.375%, and 0.5% volumetric fractions. Fly ash is also used as a partial replacement of Portland cement in all mixes. PVA-FRC mixes have been compared to length change of control concrete (devoid of fibres at 3 storage intervals: early-age (0–7 days, short-term (0–28 days, and long-term (28–112 days intervals. The shrinkage results of FRC and control concrete up to 112 days indicated that all PVA-FRC mixes exhibited higher drying shrinkage than control. The shrinkage exhibited by PVA-FRC mixes ranged from 449 to 480 microstrain, where this value was only 427 microstrain in the case of control. In addition, the longer fibres exhibited higher mass loss, thus potentially contributing to higher shrinkage.

  3. Investigation on the loss of trace elements in biological materials in different drying and ashing procedures by using radioactive tracers: Pt. 1

    International Nuclear Information System (INIS)

    Wang Yongxian; Qin Junfa; Ji Qianmei; Wu Shimin; Wang Xuepeng; Zhang Yuanxun

    1985-01-01

    By using radioactive tracers it is found that freezing dry is safe for Zn, Mo, Cd and Se in all matrices studied. Oven dry is also safe except for Se in hair. The oxygen plasma ashing does not cause any loss of Zn, Mo and Cd. Different degrees of loss were observed in oven ashing with exception of Zn and Mo in hair and shallot. It is obvious that the loss rate of the trace elements depends on their chemical forms present in the matrices. The retention of the four elements studied on the wall of quartz container can be neglected after oxygen plasma ashing. But Zn, Cd and Mo were retended in various degrees after oven ashing

  4. Effect of wear parameters on dry sliding behavior of Fly Ash/SiC particles reinforced AA 2024 hybrid composites

    Science.gov (United States)

    Bhaskar Kurapati, Vijaya; Kommineni, Ravindra

    2017-09-01

    In the present work AA 2024 alloy reinforced with mixtures of SiC and Fly Ash (FA) particles of 70 µm (5, 10 and 15 wt. %) are fabricated using the stir casting method. Both reinforcements are added in equal weight proportions. The wear test specimens are prepared from both the alloy and composite castings in the dimensions of Ф 4 mm and 30 mm lengths by the wire cut EDM process. The dry sliding wear properties of the prepared composites at room temperature are estimated by pin-on-disc wear testing equipment. The wear characteristics of the composites are studied by conducting the dry sliding wear test over loads of 0.5 Kgf, 1.0 Kgf, 1.5 Kgf, a track diameter of 60 mm and sliding times of 15 min, 30 min, 45min. The experimental results shows that the wear decreases with an increase in the weight percentage of FA and SiC particles in the matrix. Additionally wear increases with an increase in load and sliding time. Further, it is found that the wear resistance of the AA2024-Hybrid composites is higher than that of the AA2024 matrix.

  5. Radioactivity of wood ash

    International Nuclear Information System (INIS)

    Rantavaara, A.; Moring, M.

    2000-01-01

    STUK (Finnish Radiation and Nuclear Safety Authority) has investigated natural and artificial radioactivity in wood ash and radiation exposure from radionuclides in ash since 1996. The aim was to consider both handling of ash and different ways of using ash. In all 87 ash samples were collected from 22 plants using entirely or partially wood for their energy production in 1996-1997. The sites studied represented mostly chemical forest industry, sawmills or district heat production. Most plants used fluidised bed combustion technique. Samples of both fly ash and bottom ash were studied. The activity concentrations of radionuclides in samples of, e.g., dried fly ash from fuel containing more than 80% wood were determined. The means ranged from 2000 to less than 50 Bq kg -1 , in decreasing order: 137 Cs, 40 K, 90 Sr, 210 Pb, 226 Ra, 232 Th, 134 Cs, 235 U. In bott radionuclide contents decreased in the same order as in fly ash, but were smaller, and 210 Pb was hardly detectable. The NH 4 Ac extractable fractions of activities for isotopes of alkaline elements (K, Cs) in bottom ash were lower than in fly ash, whereas solubility of heavier isotopes was low. Safety requirements defined by STUK in ST-guide 12.2 for handling of peat ash were fulfilled at each of the sites. Use of ash for land-filling and construction of streets was minimal during the sampling period. Increasing this type of ash use had often needed further investigations, as description of the use of additional materials that attenuate radiation. Fertilisation of forests with wood ash adds slightly to the external irradiation in forests, but will mostly decrease doses received through use of timber, berries, mushrooms and game meat. (orig.)

  6. Statistical model to predict dry sliding wear behaviour of Aluminium-Jute bast ash particulate composite produced by stir-casting

    Directory of Open Access Journals (Sweden)

    Gambo Anthony VICTOR

    2017-06-01

    Full Text Available A model to predict the dry sliding wear behaviour of Aluminium-Jute bast ash particulate composites produced by double stir-casting method was developed in terms of weight fraction of jute bast ash (JBA. Experiments were designed on the basis of the Design of Experiments (DOE technique. A 2k factorial, where k is the number of variables, with central composite second-order rotatable design was used to improve the reliability of results and to reduce the size of experimentation without loss of accuracy. The factors considered in this study were sliding velocity, sliding distance, normal load and mass fraction of JBA reinforcement in the matrix. The developed regression model was validated by statistical software MINITAB-R14 and statistical tool such as analysis of variance (ANOVA. It was found that the developed regression model could be effectively used to predict the wear rate at 95% confidence level. The wear rate of cast Al-JBAp composite decreased with an increase in the mass fraction of JBA and increased with an increase of the sliding velocity, sliding distance and normal load acting on the composite specimen.

  7. Blackberry wines mineral and heavy metal content determination after dry ashing: multivariate data analysis as a tool for fruit wine quality control.

    Science.gov (United States)

    Amidžić Klarić, Daniela; Klarić, Ilija; Mornar, Ana; Velić, Darko; Velić, Natalija

    2015-08-01

    This study brings out the data on the content of 21 mineral and heavy metal in 15 blackberry wines made of conventionally and organically grown blackberries. The objective of this study was to classify the blackberry wine samples based on their mineral composition and the applied cultivation method of the starting raw material by using chemometric analysis. The metal content of Croatian blackberry wine samples was determined by AAS after dry ashing. The comparison between an organic and conventional group of investigated blackberry wines showed statistically significant difference in concentrations of Si and Li, where the organic group contained higher concentrations of these compounds. According to multivariate data analysis, the model based on the original metal content data set finally included seven original variables (K, Fe, Mn, Cu, Ba, Cd and Cr) and gave a satisfactory separation of two applied cultivation methods of the starting raw material.

  8. Fly ash aggregates. Vliegaskunstgrind

    Energy Technology Data Exchange (ETDEWEB)

    1983-03-01

    A study has been carried out into artificial aggregates made from fly ash, 'fly ash aggregates'. Attention has been drawn to the production of fly ash aggregates in the Netherlands as a way to obviate the need of disposal of fly ash. Typical process steps for the manufacturing of fly ash aggregates are the agglomeration and the bonding of fly ash particles. Agglomeration techniques are subdivided into agitation and compaction, bonding methods into sintering, hydrothermal and 'cold' bonding. In sintering no bonding agent is used. The fly ash particles are more or less welded together. Sintering in general is performed at a temperature higher than 900 deg C. In hydrothermal processes lime reacts with fly ash to a crystalline hydrate at temperatures between 100 and 250 deg C at saturated steam pressure. As a lime source not only lime as such, but also portland cement can be used. Cold bonding processes rely on reaction of fly ash with lime or cement at temperatures between 0 and 100 deg C. The pozzolanic properties of fly ash are used. Where cement is applied, this bonding agent itself contributes also to the strength development of the artificial aggregate. Besides the use of lime and cement, several processes are known which make use of lime containing wastes such as spray dry absorption desulfurization residues or fluid bed coal combustion residues. (In Dutch)

  9. Ash study for biogas purification

    International Nuclear Information System (INIS)

    Juarez V, R. I.

    2016-01-01

    This work evaluates the ashes generated from the wood and coal combustion process of the thermoelectric plant in Petacalco, Guerrero (Mexico) in order to determine its viability as a filter in the biogas purification process. The ash is constituted by particles of morphology and different chemical properties, so it required a characterization of the same by different analytical techniques: as was scanning electron microscopy and X-ray diffraction, in order to observe the microstructure and determine the elemental chemical composition of the particles. Prior to the analysis, a set of sieves was selected to classify as a function of particle size. Four different types of ashes were evaluated: one generated by the wood combustion (wood ash) and three more of the Petacalco thermoelectric generated by the coal combustion (wet fly ash, dry fly ash and dry bottom ash). (Author)

  10. Efficiency of using direct-flow burners and nozzles in implementation of dry-bottom ash removal at the TPP-210A boiler furnace

    Science.gov (United States)

    Arkhipov, A. M.; Kanunnikov, A. A.; Kirichkov, V. S.; Prokhorov, V. B.; Fomenko, M. V.; Chernov, S. L.

    2017-02-01

    In reconstruction of operating pulverized coal-fired boilers, one of the main factors is the choice of a method for slag removal: dry bottom ash removal (DBAR) or slag-tap removal (STR). In this case, ecological and economic aspects should be taken into account, and also the early ignition of pulverized coal fuel, the reliability of operation of the furnace walls in the mode without slagging, and the stability of slag removal should be provided. In this work, issues of changeover of the pulverized coal-fired boilers of the TPP-210A type from the STR mode to the DBAR mode are considered. As of today, the main problems during the operation of these boilers are the high emissions of nitrogen oxides together with flue gases into the atmosphere and the appropriated payoffs, a small range of loads available, the necessity of stabilization of the pulverizedcoal flame sustainability by using the highly reactive fuel, large mechanical fuel underburning, etc. Results of studying aerodynamics of a furnace with DBAR obtained in the process of physical simulation are given; technical solutions and preliminary design (configuration of burners and nozzles in the boiler furnace, conceptual design of the pulverized coal burner, configuration of TPP-210A boiler with the low heat liberation of furnace cross-section and volumetric heat release) are set forth, which are associated with the optimization of aerodynamics of furnace volume, when the direct-flow burners and nozzles are used, and with organization of the efficient staged combustion of solid fuel. Two versions of possible modernization of a boiler unit are considered. Under conditions of the planned increase in the steam production capacity, the most promising measures are as follows: the DBAR implementation with reducing heat releases of the cross-section and volume of the furnace approximately by half, the installation of the direct-flow burners and nozzles with injection of recirculation gases into the active combustion

  11. Engineering properties of fly ash concrete

    International Nuclear Information System (INIS)

    Hilmi Mahmud

    1999-01-01

    This paper presents some of the engineering properties of Malaysian fly ash concrete. Workability, compressive, flexural, tensile splitting, drying shrinkage, elastic modulus and non destructive tests were performed on fly ash and control OPC concrete specimens. Data show that concrete containing 25% fly ash replacement of cement exhibit superior or similar engineering properties to that normal concrete without fly ash. These encouraging results demonstrated the technical merits of incorporating fly ash in concrete and should pave the way for wide scale use of this versatile material in the Malaysian construction industry. (author)

  12. Zooplankton biomass (displacement volume, dry mass, ash-free dry mass) data collected in Eastern Central Atlantic during CIPREA project from 1978-07-25 to 1978-09-12 by France (NODC Accession 0070783)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Zooplankton biomass (displacement volume, dry mass, and ashfree dry mass) data collected in Eastern Central Atlantic during CIPREA project in Jul - Sep 1978 by...

  13. Radioactivity of wood ash; Puun tuhkan radioaktiivisuus

    Energy Technology Data Exchange (ETDEWEB)

    Rantavaara, A.; Moring, M

    2000-01-01

    STUK (Finnish Radiation and Nuclear Safety Authority) has investigated natural and artificial radioactivity in wood ash and radiation exposure from radionuclides in ash since 1996. The aim was to consider both handling of ash and different ways of using ash. In all 87 ash samples were collected from 22 plants using entirely or partially wood for their energy production in 1996-1997. The sites studied represented mostly chemical forest industry, sawmills or district heat production. Most plants used fluidised bed combustion technique. Samples of both fly ash and bottom ash were studied. The activity concentrations of radionuclides in samples of, e.g., dried fly ash from fuel containing more than 80% wood were determined. The means ranged from 2000 to less than 50 Bq kg{sup -1}, in decreasing order: {sup 137}Cs, {sup 40}K, {sup 90}Sr, {sup 210}Pb,{sup 226}Ra, {sup 232}Th, {sup 134}Cs, {sup 235}U. In bott radionuclide contents decreased in the same order as in fly ash, but were smaller, and {sup 210}Pb was hardly detectable. The NH{sub 4}Ac extractable fractions of activities for isotopes of alkaline elements (K, Cs) in bottom ash were lower than in fly ash, whereas solubility of heavier isotopes was low. Safety requirements defined by STUK in ST-guide 12.2 for handling of peat ash were fulfilled at each of the sites. Use of ash for land-filling and construction of streets was minimal during the sampling period. Increasing this type of ash use had often needed further investigations, as description of the use of additional materials that attenuate radiation. Fertilisation of forests with wood ash adds slightly to the external irradiation in forests, but will mostly decrease doses received through use of timber, berries, mushrooms and game meat. (orig.)

  14. Practical use of dry desulfurization equipment using coal ash and effective use of used desulfurizer. Sekitanbai riyo kanshiki datsuryu sochi no jitsuyoka to shiyozumi datsuryuzai no yukoriyo ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, T.; Ueno, T. (The Hokkaido Electric Power CO. Inc., Hokkaido (Japan))

    1992-01-30

    Practical use of dry desulfurization equipment using coal ash installed in Atsuma power plant no.1 is explained. Outline of dry desulferization process is consisted of basic principles and structure of the process which includes desulfurizer production equipment and absorption equipment. When compared with conventional wet process, equipments for waste water and for reheating of exhaust gas are not necessary, and operation maintenance has been more convenient with the simplification of the system and absorber has graded up the elimination function. Advantages of simplification of treatment of used desulfurizer, and absorption of sulfurdioxide by desulfurizer together with characteristics of desulfurizer production are given. As far as practical macineries are concerned, outline of instrument facilities, construction technology and results of experimental operation are reported. Effective Use of desulfurizer using deodorant and hedro treatment has been verified from ammonium absorption experiment and practical investigation results. However use of hedro material has required, conformity of surface caking technology, under water caking technology, under water covering technology and effect on under water living environment. 13 figs., 4 tabs.

  15. Volcanic ash impacts on critical infrastructure

    Science.gov (United States)

    Wilson, Thomas M.; Stewart, Carol; Sword-Daniels, Victoria; Leonard, Graham S.; Johnston, David M.; Cole, Jim W.; Wardman, Johnny; Wilson, Grant; Barnard, Scott T.

    2012-01-01

    Volcanic eruptions can produce a wide range of hazards. Although phenomena such as pyroclastic flows and surges, sector collapses, lahars and ballistic blocks are the most destructive and dangerous, volcanic ash is by far the most widely distributed eruption product. Although ash falls rarely endanger human life directly, threats to public health and disruption to critical infrastructure services, aviation and primary production can lead to significant societal impacts. Even relatively small eruptions can cause widespread disruption, damage and economic loss. Volcanic eruptions are, in general, infrequent and somewhat exotic occurrences, and consequently in many parts of the world, the management of critical infrastructure during volcanic crises can be improved with greater knowledge of the likely impacts. This article presents an overview of volcanic ash impacts on critical infrastructure, other than aviation and fuel supply, illustrated by findings from impact assessment reconnaissance trips carried out to a wide range of locations worldwide by our international research group and local collaborators. ‘Critical infrastructure’ includes those assets, frequently taken for granted, which are essential for the functioning of a society and economy. Electricity networks are very vulnerable to disruption from volcanic ash falls. This is particularly the case when fine ash is erupted because it has a greater tendency to adhere to line and substation insulators, where it can cause flashover (unintended electrical discharge) which can in turn cause widespread and disruptive outages. Weather conditions are a major determinant of flashover risk. Dry ash is not conductive, and heavy rain will wash ash from insulators, but light rain/mist will mobilise readily-soluble salts on the surface of the ash grains and lower the ash layer’s resistivity. Wet ash is also heavier than dry ash, increasing the risk of line breakage or tower/pole collapse. Particular issues for water

  16. Geopolymer obtained from coal ash

    International Nuclear Information System (INIS)

    Conte, V.; Bissari, E.S.; Uggioni, E.; Bernardin, A.M.

    2011-01-01

    Geopolymers are three-dimensional alumino silicates that can be rapidly formed at low temperature from naturally occurring aluminosilicates with a structure similar to zeolites. In this work coal ash (Tractebel Energy) was used as source of aluminosilicate according a full factorial design in eight formulations with three factors (hydroxide type and concentration and temperature) and two-levels. The ash was dried and hydroxide was added according type and concentration. The geopolymer was poured into cylindrical molds, cured (14 days) and subjected to compression test. The coal ash from power plants belongs to the Si-Al system and thus can easily form geopolymers. The compression tests showed that it is possible to obtain samples with strength comparable to conventional Portland cement. As a result, temperature and molarity are the main factors affecting the compressive strength of the obtained geopolymer. (author)

  17. Properties of Fly Ash Blocks Made from Adobe Mould

    Science.gov (United States)

    Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

    2018-06-01

    Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

  18. Properties of Fly Ash Blocks Made from Adobe Mould

    Science.gov (United States)

    Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

    2018-02-01

    Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

  19. Heavy metals in MSW incineration fly ashes

    DEFF Research Database (Denmark)

    Ferreira, Celia; Ribeiro, Alexandra B.; Ottosen, Lisbeth M.

    2003-01-01

    Incineration is a common solution for dealing with the increasing amount of municipal solid waste (MSW). During the process, the heavy metals initially present in the waste go through several transformations, ending up in combustion products, such as fly ash. This article deals with some issues...... related to the combustion of MSW and the formation of fly ash, especially in what concerns heavy metals. Treatment of the flue gas in air pollution control equipment plays an important role and the basic processes to accomplish this are explained. Fly ash from a semi-dry flue gas treatment system...

  20. Determination of Total Solids and Ash in Algal Biomass: Laboratory Analytical Procedure (LAP)

    Energy Technology Data Exchange (ETDEWEB)

    Van Wychen, Stefanie; Laurens, Lieve M. L.

    2016-01-13

    This procedure describes the methods used to determine the amount of moisture or total solids present in a freeze-dried algal biomass sample, as well as the ash content. A traditional convection oven drying procedure is covered for total solids content, and a dry oxidation method at 575 deg. C is covered for ash content.

  1. Silica from Ash

    Indian Academy of Sciences (India)

    management, polymer composites and chemical process design. Figure 1 Difference in color of the ash ... The selection of ash is important as the quality of ash determines the total amount as well as quality of silica recoverable Ash which has undergone maximum extent of combustion is highly desirable as it contains ...

  2. Volcanic Ash fall Impact on Vegetation, Colima 2005

    Science.gov (United States)

    Garcia, M. G.; Martin, A.; Fonseca, R.; Nieto, A.; Radillo, R.; Armienta, M.

    2007-05-01

    An ash sampling network was established arround Colima Volcano in 2005. Ash fall was sampled on the North, Northeast, East, Southeast, South, Southwest and West of the volcano. Samples were analyzed for ash components, geochemistry and leachates. Ash fall ocurred on April (12), May (10, 23), June (2, 6, 9, 10, 12, 14), July (27), September (27), October (23) and November (24). Most of the ash is made of andesitic dome-lithics but shows diferences in crystal, juvenile material and lithic content. In May, some samples contained grey and dark pumice (scoria). Texture varies from phi >4 to phi 0. Leachate concentration were low: SO4 (7.33-54.19) Cl- (2.29-4.97) and F- (0.16-0.37). During 2005, Colima Volcano's ash fall rotted some of the guava and peach fruits and had a drying effect on spearment and epazote plants. Even these small ash amounts could have hindered sugar cane and agave growth.

  3. Stabilization of expansive soil using bagasse ash & lime | Wubshet ...

    African Journals Online (AJOL)

    7-5 soil on the AASHTO classification was stabilized using 3% lime, 15% bagasse ash and 15% bagasse ash in combination with 3% lime by dry weight of the soil. The effect of the additives on the soil was investigated with respect to plastcity, ...

  4. Quality Assessment of Soaps Produced from Palm Bunch Ash ...

    African Journals Online (AJOL)

    Quality Assessment of Soaps Produced from Palm Bunch Ash-Derived Alkali and ... Journal of Applied Sciences and Environmental Management ... The remedial process involved subjecting the dried palm bunch matter to total combustion, ...

  5. Greener management practices - ash mound reclamation

    Energy Technology Data Exchange (ETDEWEB)

    Kapur, S.L.; Shyam, A.K.; Soni, R. [National Thermal Power Corp. Ltd., New Delhi (India)

    2002-12-01

    The dry ash handling system at Dadri has been pioneered for the first time in India by the National Thermal Power Corporation (NTPC). The system is similar to that at the Drax power station in England. The paper reports the successful experimental trials carried out on vegetation of temporary ash mounds to assess the growth potential of local herbs, shrubs, trees and grasses directly on ash with no soil cover or fertiliser. These were extended to trials directly on the available (completed) mound surfaces. The grass Cynodon dactylon germinated well as did seeds of tree species including the Casurarina and Eucalyptus. It is hoped that efforts at Dadri will ultimately transform the ash into a productive and self sustaining ecosystem, as leaf fall adds additional organic material and the weathering process continues. 6 refs., 6 figs.

  6. Volcanic Ash Data Assimilation System for Atmospheric Transport Model

    Science.gov (United States)

    Ishii, K.; Shimbori, T.; Sato, E.; Tokumoto, T.; Hayashi, Y.; Hashimoto, A.

    2017-12-01

    The Japan Meteorological Agency (JMA) has two operations for volcanic ash forecasts, which are Volcanic Ash Fall Forecast (VAFF) and Volcanic Ash Advisory (VAA). In these operations, the forecasts are calculated by atmospheric transport models including the advection process, the turbulent diffusion process, the gravitational fall process and the deposition process (wet/dry). The initial distribution of volcanic ash in the models is the most important but uncertain factor. In operations, the model of Suzuki (1983) with many empirical assumptions is adopted to the initial distribution. This adversely affects the reconstruction of actual eruption plumes.We are developing a volcanic ash data assimilation system using weather radars and meteorological satellite observation, in order to improve the initial distribution of the atmospheric transport models. Our data assimilation system is based on the three-dimensional variational data assimilation method (3D-Var). Analysis variables are ash concentration and size distribution parameters which are mutually independent. The radar observation is expected to provide three-dimensional parameters such as ash concentration and parameters of ash particle size distribution. On the other hand, the satellite observation is anticipated to provide two-dimensional parameters of ash clouds such as mass loading, top height and particle effective radius. In this study, we estimate the thickness of ash clouds using vertical wind shear of JMA numerical weather prediction, and apply for the volcanic ash data assimilation system.

  7. Triple oxygen and sulfur isotope analyses of sulfate extracted from voluminous volcanic ashes in the Oligocene John Day Formation: insight into dry climate conditions and ozone contribution to supereruptions

    Science.gov (United States)

    Workman, J.; Bindeman, I. N.; Martin, E.; Retallack, G.; Palandri, J. L.; Weldon, N.

    2014-12-01

    Large volume pyroclastic silicic eruptions emit hundreds of megatons of SO2 into the troposphere and stratosphere that is oxidized into sulfuric acid (H2SO4) by a variety of reactions with mass independent oxygen signatures (MIF), Δ17O>0. Sulfuric acid is then preserved as gypsum in parental volcanic deposits. Diagenic effects are mass dependent and can dilute, but otherwise do not affect MIF ratios. Pleistocene Yellowstone and Bishop tuffs and modern volcanic eruptions preserved under arid climate conditions in North American playa lakes, preserve small amounts of volcanic sulfate as gypsum. This gypsum's Δ17O>0, in combination with isotopic variations of δ18O, δ33S and δ34S is distinct from sedimentary sulfate and reveals its original MIF sulfate isotopic signal and the effect of super eruptions on the atmosphere, and ozone consumption in particular. We use linear algebraic equations to resolve volcanic versus sedimentary (MIF=0) sources. We have found that many large volume ignimbrites have very high initial Δ17O in volcanic sulfate that can only be acquired from reaction with stratospheric ozone. We here investigate nine thick (>2 m) ash beds ranging in age from ~33-23 Ma in the John Day Formation of central Oregon, including massive 28.6 Ma Picture Gorge tuff of newly identified Crooked River supercaldera. The 28.6 Ma Picture Gorge tuff (PGT) has the highest measured Δ17O of 3.5‰, and other tuffs (Tin Roof, Biotite, Deep Creek) have +1.3 to 3.4‰ Δ17O excesses. Sulfate from modern smaller tropospheric eruptions studied for comparison have a resolvable 0.4‰ range consistent with liquid-phase based H2O2 oxidation. The PGT is coeval with the ignimbrite flare-up in western N. America, the 28-29 Ma eruption of the 5000 km3 Fish Canyon tuff and the 28 Ma Never Summer Field eruption in Nebraska-Colorado that have the highest measured Δ17O of 6‰ (Bao et al. 2003). We speculate on the climatic/atmospheric effects of these multiple ~28 Ma supereruptions

  8. Fiscal 2000 project of inviting proposals for international joint research - invitation for international proposal (Power generation No.1). Achievement report on development of novel high-performance dry type desulfurization agent made from coal ash; 2000 nendo kokusai kyodo kenkyu teian kobo jigyo - kokusai teian kobo (hatsuden No.1). Sekitanbai wo genryo to suru shinki koseino kanshiki datsuryuzai no kaihatsu to riyo seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Efforts are made to develop a technology of using quicklime instead of slaked lime for a reduction in desulfurization cost, based on the technology of the coal ash utilizing dry type desulfurization device operating on coal ash, slaked lime, and gypsum, as hardened by hydration. Activities are conducted in the three fields of (1) basic study, (2) desulfurization agent bench-scale manufacturing test, and (3) study for putting the technology to practical application. In field (1), the basics are studied of the lime slaking process in the manufacture of a dry type desulfurization agent from quicklime, the mechanism is elucidated of the generation of active desulfurization substances, and effective utilization is studied of the desulfurization agent after use. In field (3), conceptual designs are prepared, cost efficiency of desulfurization systems are evaluated, simplified absorption systems are studied, and the trends of dry type desulfurization systems are surveyed. The cost of desulfurization under development is equivalent to that of the wet type method (limestone-gypsum system) when the used desulfurization agent is discarded, and is approximately 60% of the wet type method when the whole amount is effectively utilized. (NEDO)

  9. Biomass ash utilization

    Energy Technology Data Exchange (ETDEWEB)

    Bristol, D.R.; Noel, D.J.; O`Brien, B. [HYDRA-CO Operations, Inc., Syracuse, NY (United States); Parker, B. [US Energy Corp., Fort Fairfield, ME (United States)

    1993-12-31

    This paper demonstrates that with careful analysis of ash from multiple biomass and waste wood fired power plants that most of the ash can serve a useful purpose. Some applications require higher levels of consistency than others. Examples of ash spreading for agricultural purposes as a lime supplement for soil enhancement in Maine and North Carolina, as well as a roadbase material in Maine are discussed. Use of ash as a horticultural additive is explored, as well as in composting as a filtering media and as cover material for landfills. The ash utilization is evaluated in a framework of environmental responsibility, regulations, handling and cost. Depending on the chemical and physical properties of the biomass derived fly ash and bottom ash, it can be used in one or more applications. Developing a program that utilizes ash produced in biomass facilities is environmentally and socially sound and can be financially attractive.

  10. Electrodialytic removal of cadmium from straw combustion fly ash

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Villumsen, Arne

    2004-01-01

    Fly ash from straw combustion contains valuable nutrients when returned to agricultural soils. In many instances, however, this fly ash may contain heavy metals, such as cadmium, at levels which often exceed the limits given by the Danish legislation. Thus before utilizing the nutrients, cadmium...... must be removed from these ashes. The use of an electrodialytic remediation method to remove cadmium from fly ash arising from straw combustion and containing 11.2 mg Cd kg$+-1$/ DM (dry matter) was accessed. After 36 days of remediation at a constant current density of 5.6 mA cm$+-2$/ more than 97...

  11. Asymmetric Ashes

    Science.gov (United States)

    2006-11-01

    , it is. "This has some impact on the use of Type Ia supernovae as standard candles," says Ferdinando Patat. "This kind of supernovae is used to measure the rate of acceleration of the expansion of the Universe, assuming these objects behave in a uniform way. But asymmetries can introduce dispersions in the quantities observed." "Our discovery puts strong constraints on any successful models of thermonuclear supernova explosions," adds Wang. Models have suggested that the clumpiness is caused by a slow-burn process, called 'deflagration', and leaves an irregular trail of ashes. The smoothness of the inner regions of the exploding star implies that at a given stage, the deflagration gives way to a more violent process, a 'detonation', which travels at supersonic speeds - so fast that it erases all the asymmetries in the ashes left behind by the slower burning of the first stage, resulting in a smoother, more homogeneous residue.

  12. Radioisotope conveyor ash meter

    International Nuclear Information System (INIS)

    Savelov, V.D.

    1994-01-01

    Radioisotope conveyor ash meter realizes persistent measuring of ashiness of coal and products of its enrichment on the belt conveyor without contact. The principle of ash meter acting is based on functional dependence of the gamma radiation flows backscattering intensity of radioisotope sources from the ash volume content in the controlled fuel. Facility consists from the ashiness transducer and the processing and control device

  13. Expansion control for cementation of incinerated ash

    International Nuclear Information System (INIS)

    Nakayama, T.; Suzuki, S.; Hanada, K.; Tomioka, O.; Sato, J.; Irisawa, K.; Kato, J.; Kawato, Y.; Meguro, Y.

    2015-01-01

    A method, in which incinerated ash is solidified with a cement material, has been developed to dispose of radioactive incinerated ash waste. A small amount of metallic Al, which was not oxidized in the incineration, existed in the ash. When such ash was mixed with a cement material and water, alkaline components in the ash and the cement were dissolved in the mixing water and then metallic Al reaction with the alkaline compounds resulted in generation of H 2 . Because the H 2 generation began immediately just after the mixing, H 2 bubbles pushed up the mixed grout material and an expanded solidified form was obtained. The expansion leads to lowering the strength of the solidified form and making harmful void. In this study, we tried to control H 2 generation from the reaction of metallic Al in the cementation by means of following two methods, one was a method to let metallic Al react prior to the cementation and the other was a method to add an expansion inhibitor that made an oxide film on the surface of metallic Al. In the pre-treatment, the ash was soaked in water in order to let metallic Al react with it, and then the ash with the immersion solution was dried at 105 Celsius degrees. The pre-treated ash was mixed with an ordinary portland cement and water. The inhibitor of lithium nitrite, sodium nitrite, phosphoric acid, or potassium dihydrogen phosphate was added at the mixing process. The solidified forms prepared using the pre-treated ash and lithium nitrite were not expanded. Phosphoric acid and sodium nitrite were effective for expansion control, but potassium dihydrogen phosphate did not work. (authors)

  14. Experimental Study on Durability Improvement of Fly Ash Concrete with Durability Improving Admixture

    OpenAIRE

    Quan, Hong-zhu; Kasami, Hideo

    2014-01-01

    In order to improve the durability of fly ash concrete, a series of experimental studies are carried out, where durability improving admixture is used to reduce drying shrinkage and improve freezing-thawing resistance. The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on the performance of fly ash concrete are discussed in this paper. The results show that by using durability improving admixture in nonair-entraining fly ash concrete,...

  15. Wood ash used as partly sand and/or cement replacement in mortar

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Esben Østergaard; Jensen, Pernille Erland

    2016-01-01

    , and the present work reports a characterization of three different WAs. Properties of mortar samples with the WAs used as partly cement and/or sand replacement are reported. Compressive strength development and porosity are the mortar properties in focus. The overall aim of the work is to evaluate the influence...... of the ashes were dry and sampled just after the incineration, whereas one ash had a water content of 15%, because the ash was sprayed with water to avoid dust during ash handling at the incineration plant. Regardless of replacing cement or sand with WAs, the compressive strength decreased compared...... to a reference without ash, however, the decrease was small for two of the ashes. Using the ash with the high LoI resulted in significantly lower compressive strength compared to the other two ashes. The mortar samples with two of the ashes (with low LoI) had qualities, which were very encouraging in order...

  16. Increase in efficiency and reduction of generation cost at hard coal-fired power plants. Post-combustion of combustion residues from co-firing of RDF and biomass during dry ash removal

    Energy Technology Data Exchange (ETDEWEB)

    Baur, Guenter [Magaldi Power GmbH, Esslingen (Germany); Spindeldreher, Olaf [RWE Generation SE, Werne (Germany); RWE Generation SE, Essen (Germany)

    2013-09-01

    Secondary as well as substitute fuels are being used in hard coal-fired power plants to improve efficiency and to enlarge fuel flexibility. However, grinding and firing systems of the existing coal-fired plants are not designed for those co-fuels. Any deterioration of the combustion performance would reduce the power output and increase ash disposal costs by increased content of combustion residues. The application of air-cooled ash removal, with simultaneous and controlled post-combustion of unburned residues on the conveyor belt, enlarges the furnace and maintains combustion efficiency even with different fuel qualities. Plant efficiency can also be increased through heat recovery. (orig.)

  17. Flue gas desulfurization gypsum and fly ash

    International Nuclear Information System (INIS)

    1992-05-01

    The Cumberland Fossil Plant (CUF) is located in Stewart County, Tennessee, and began commercial operation in 1972. This is the Tennessee Valley Authority's newest fossil (coal-burning) steam electric generating plant. Under current operating conditions, the plant burns approximately seven million tons of coal annually. By-products from the combustion of coal are fly ash, approximately 428,000 tons annually, and bottom ash, approximately 115,000 tons annually. Based on historical load and projected ash production rates, a study was initially undertaken to identify feasible alternatives for marketing, utilization and disposal of ash by-products. The preferred alternative to ensure that facilities are planned for all by-products which will potentially be generated at CUF is to plan facilities to handle wet FGD gypsum and dry fly ash. A number of different sites were evaluated for their suitability for development as FGD gypsum and ash storage facilities. LAW Engineering was contracted to conduct onsite explorations of sites to develop information on the general mature of subsurface soil, rock and groundwater conditions in the site areas. Surveys were also conducted on each site to assess the presence of endangered and threatened species, wetlands and floodplains, archaeological and cultural resources, prime farmland and other site characteristics which must be considered from an environmental perspective

  18. Solubility and transport of arsenic coal ash

    International Nuclear Information System (INIS)

    Iturbe, R.; Cruickshank, C.; Vega, E.; Silva, A.E.

    1996-01-01

    An experimental method combined with a numerical model allows a comparison of two methods for the disposal of ash that contains arsenic, from the Rio Escondido coal-fired power plant. The calculation yields significant differences in aquifer migration times for the site. The wet disposal method gave 10 years time and the dry method gave 22 years. Experiments were performed on the rate of dissolution of the arsenic from ash samples; and these results indicate a first order kinetics reaction. 8 refs., 8 figs., 8 tabs

  19. Fly ash carbon passivation

    Science.gov (United States)

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  20. Shedding of ash deposits

    DEFF Research Database (Denmark)

    Zbogar, Ana; Frandsen, Flemming; Jensen, Peter Arendt

    2009-01-01

    Ash deposits formed during fuel thermal conversion and located on furnace walls and on convective pass tubes, may seriously inhibit the transfer of heat to the working fluid and hence reduce the overall process efficiency. Combustion of biomass causes formation of large quantities of troublesome...... ash deposits which contain significant concentrations of alkali, and earth-alkali metals. The specific composition of biomass deposits give different characteristics as compared to coal ash deposits, i.e. different physical significance of the deposition mechanisms, lower melting temperatures, etc....... Low melting temperatures make straw ashes especially troublesome, since their stickiness is higher at lower temperatures, compared to coal ashes. Increased stickiness will eventually lead to a higher collection efficiency of incoming ash particles, meaning that the deposit may grow even faster...

  1. Ash study for biogas purification; Estudio de cenizas para purificacion de biogas

    Energy Technology Data Exchange (ETDEWEB)

    Juarez V, R. I.

    2016-07-01

    This work evaluates the ashes generated from the wood and coal combustion process of the thermoelectric plant in Petacalco, Guerrero (Mexico) in order to determine its viability as a filter in the biogas purification process. The ash is constituted by particles of morphology and different chemical properties, so it required a characterization of the same by different analytical techniques: as was scanning electron microscopy and X-ray diffraction, in order to observe the microstructure and determine the elemental chemical composition of the particles. Prior to the analysis, a set of sieves was selected to classify as a function of particle size. Four different types of ashes were evaluated: one generated by the wood combustion (wood ash) and three more of the Petacalco thermoelectric generated by the coal combustion (wet fly ash, dry fly ash and dry bottom ash). (Author)

  2. Ash Utilisation 2012. Ashes in a Sustainable Society. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    Conference themes: Risk assessment, Fly ash- Road construction, Recycling and Greenhouse gases, Storage of ashes, Fertilizer, Metal Mining, Support and Barriers, Construction Material, Civil Engineering, and MSWI bottom ash.

  3. Experience in the radiometric on-line determination of the ash content of raw lignite at the Hagenwerder power station

    International Nuclear Information System (INIS)

    Koerner, G.; Leonhardt, J.; Thuemmel, H.W.; Fritzsche, D.

    1986-01-01

    For power station feed control an ash monitoring system has been working for one year. It comprises a by-pass sampling system including the scatter-transmission ash gauge KRAS-1 (total error 3.8 weight percentage ash on dry basis) which is used for calibrating the non-contact on-stream computer-controlled ash gauge KRAS-2 based on the 2-energy transmission method (total error 4.5 weight percentage ash on dry basis). The economic benefit is estimated to 1.4 million Mark per year. (author)

  4. Trace elements in coal ash

    Science.gov (United States)

    Deonarine, Amrika; Kolker, Allan; Doughten, Michael W.

    2015-01-01

    Coal ash is a residual waste product primarily produced by coal combustion for electric power generation. Coal ash includes fly ash, bottom ash, and flue-gas desulfurization products (at powerplants equipped with flue-gas desulfurization systems). Fly ash, the most common form of coal ash, is used in a range of products, especially construction materials. A new Environmental Protection Agency ruling upholds designation of coal ash as a non-hazardous waste under Subtitle D of the Resource Conservation and Recovery Act, allowing for the continued beneficial use of coal ash and also designating procedures and requirements for its storage.

  5. Removal of chloride from MSWI fly ash.

    Science.gov (United States)

    Chen, Wei-Sheng; Chang, Fang-Chih; Shen, Yun-Hwei; Tsai, Min-Shing; Ko, Chun-Han

    2012-10-30

    The high levels of alkali chloride and soluble metal salts present in MSWI fly ash is worth noting for their impact on the environment. In addition, the recycling or reuse of fly ash has become an issue because of limited landfill space. The chloride content in fly ash limits its application as basis for construction materials. Water-soluble chlorides such as potassium chloride (KCl), sodium chloride (NaCl), and calcium chloride hydrate (CaCl(2) · 2H(2)O) in fly ash are easily washed away. However, calcium chloride hydroxide (Ca(OH)Cl) might not be easy to leach away at room temperature. The roasting and washing-flushing processes were applied to remove chloride content in this study. Additionally, air and CO(2) were introduced into the washing process to neutralize the hazardous nature of chlorides. In comparison with the water flushing process, the roasting process is more efficient in reducing the process of solid-liquid separation and drying for the reuse of Cl-removed fly ash particles. In several roasting experiments, the removal of chloride content from fly ash at 1050°C for 3h showed the best results (83% chloride removal efficiency). At a solid to liquid ratio of 1:10 the water-flushing process can almost totally remove water-soluble chloride (97% chloride removal efficiency). Analyses of mineralogical change also prove the efficiency of the fly ash roasting and washing mechanisms for chloride removal. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Technical note - the incorporation of ash content into gas content

    Energy Technology Data Exchange (ETDEWEB)

    Creech, M.; Mahoney, M. [Powercoal Pty. Ltd., Budgewoi, NSW (Australia)

    1995-12-31

    For gas content analysis in recent years, it has been standard procedure to report results on a `dry ash free` (daf) basis, under the assumption that gas only adsorbs onto coaly material. In order to test the relationship between ash and gas content, samples of various rock types were taken from two drillholes in the Newcastle Coalfield. The results of this study confirmed the correlation between gas content and ash, providing an accurate means of relating gas contents for all carbonaceous rock types. 4 refs., 5 figs., 1 tab.

  7. Pengaruh Penambahan Limbah Padat Abu Terbang Batubara(fly Ash) Terhadap Kekuatan Tekan Dan Porositas Genteng Tanah Liat Kabupaten Pringsewu

    OpenAIRE

    Febriyansyah, Puji; Tarkono,; Zulhanif,

    2013-01-01

    Fly ash, chemicallyis analumino-silicamineral containing Ca, K, and Na elements, fly ash has amoderate to high bonding capacity characteristic , and has acement-forming properties. In this study the authors use the industrial fly ash coal waste as an alternative mixture of tile manufacture. The tiles manufactured by mixing clay, sand, water and fly ash. Then smoothed with ekstuder machine and forming kuweh then aerate for 3 days, before do the dieing process . Tile dried for 4 days, then do f...

  8. Protecting black ash from the emerald ash borer

    Science.gov (United States)

    Les Benedict

    2010-01-01

    Black ash (Fraxinus nigra) is an important resource for Tribes in the Northeast and Great Lakes regions of the North American continent. Ash in North America is being threatened with widespread destruction as a result of the introduction of emerald ash borer beetle (Agrilus planipennis) in 2002. Measures are being taken to slow the spread of emerald ash borer beetle....

  9. DETERMINATION OF METAL CONTENT AND AN ASSESSMENT OF THE POTENTIAL USE OF WASTE CASHEW NUT ASH (CNSA) AS SOURCE FOR POTASH PRODUCTION

    OpenAIRE

    Mary Bosede Ogundiran; Joshua Olajiire Babayemi; Chima Gregory Nzeribe

    2011-01-01

    The potential use of waste cashew nut shell (CNS) ash as a source for potash production was investigated in this study. Managing waste ash generated from cashew nut processing is a major challenge, as land filling and open dumping of the waste ashes have been the main options in management of the ash in Nigeria. Economically viable ways of using waste ash rather than having to dispose of it have to be investigated. The CNS was air-dried for 4 weeks and combusted to ashes; the resulting ash wa...

  10. Forest fuel, ashes and ecology

    International Nuclear Information System (INIS)

    Lundborg, A.

    1994-01-01

    Large-scale use of bioenergy is an essential measure if several of the major environmental problems are to be solved. However, it is important to utilize the possibilities available to produce biofuel without creating new environmental problems. Whole-tree removal gives a considerable reduction in the nitrogen lead which, in combination with the return of ashes, counteracts the nutrient imbalance and acidification in southern Sweden. Forestry of that kind should lead to lower total leaching of nitrogen in comparison with conventional forestry. In situations where there is high deposition of atmospheric sulphur and nitrogen, fuel removal with return of a moderate dose of slowly dissolvable ashes should be a good soil management measure. The humus status and flora/fauna always require some kind of consideration. With compensation measures and retained nutrient status there should be no problems with the humus status on most soils. However, on poor and dry soils, it is suitable to avoid whole-tree removal on account of the humus status. Consideration to nature includes, for example, increasing the number of broad-leaf trees, old trees and dead wood (preferably the trunks). These measures concern all types of forestry and are not linked directly with fuel removal. Removal of felling residues and return of ashes are of minor importance in comparison with this and fit well into forestry adapted to natural values. With correct planning and accomplishment of the removal of forest fuel the natural values of the forest can be retained or even improved. Forestry where fuel is also produced can be designed whereby negative effects are avoided at the same time as positive environmental effects are obtained. 68 refs, 5 figs, 3 tabs

  11. Considerations on comprehensive risk assessment and mitigation planning of volcanic ash-fall

    International Nuclear Information System (INIS)

    Toshida, Kiyoshi

    2010-01-01

    Volcanic ash-fall is inevitable hazard throughout Japan, and causes wide range of effects due to its physical and chemical properties. Nuclear power plants in Japan face the necessity to assess the risk from volcanic ash-fall. Risk assessment of the volcanic ash-fall should include engineering solution and mitigation planning as well as the ash-fall hazard. This report points out the characteristics for reducing the various effects of volcanic ash-fall as follows. Large-scale eruptions produce prominent volcanic ash-falls that can approach power plants at a great distance. Aftermath hazards of ash-fall events, such as remobilization of fine ash particles and generation of lahars, require further assessments. The kind and extent of damages becomes greater whenever ash is wet. Wet ash requires separate assessments in contrast to dry ash. The mitigation and recovery measures at power plants involve quick cleanup operations of volcanic ash. Those operations should be prepared through comprehensive risk assessment, and by cooperation with authorities, during pre-eruption repose period. The comprehensive assessment for volcanic ash-fall hazards, however, has yet to be conducted. Development of risk communication method may result in increased implementation mitigation planning. Numerical analysis of the ash-fall hazards provides quantitative data on particle motions that can be used in the risk assessment. In order to implement the quantitative assessment method, the verification on the effect of ambient air condition to the altitude of volcanic ash cloud is necessary. We need to develop a three-dimensional model of volcanic ash cloud, and calculate motions of ash clouds under multiple conditions of ambient air. (author)

  12. STABILIZATION OF GRANULAR VOLCANIC ASH IN SANA'A AREA

    Directory of Open Access Journals (Sweden)

    SUBHI A. ALI

    2014-02-01

    Full Text Available This paper presents the findings of compaction and strength characteristics of a Granular Volcanic Ash from Sana'a city center, which was mixed with various percentages of two binders to form a stabilized material namely; fine soil and Portland cement. The study showed a significant improvement of the Volcanic Ash properties. The maximum dry density and California bearing ration (CBR were considerably increased by addition of stabilizers at different rates for different binder contents. Optimum fine soil content for the maximum dry density and CBR is determined. A relationship between the optimum moisture content and the binder combination content for different fine soil percentages was established.

  13. First international ash marketing and technology conference

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    A total of 42 papers were presented in sessions with the following headings: production and disposal of ash - an international review; environmental, health, safety, and legal aspects of ash handling; marketing of ash; development of new uses for ash; cementitious use of ash; ash in manufactured products; and geotechnical uses of ash.

  14. Ash cloud aviation advisories

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T.J.; Ellis, J.S. [Lawrence Livermore National Lab., CA (United States); Schalk, W.W.; Nasstrom, J.S. [EG and G, Inc., Pleasanton, CA (United States)

    1992-06-25

    During the recent (12--22 June 1991) Mount Pinatubo volcano eruptions, the US Air Force Global Weather Central (AFGWC) requested assistance of the US Department of Energy`s Atmospheric Release Advisory Capability (ARAC) in creating volcanic ash cloud aviation advisories for the region of the Philippine Islands. Through application of its three-dimensional material transport and diffusion models using AFGWC meteorological analysis and forecast wind fields ARAC developed extensive analysis and 12-hourly forecast ash cloud position advisories extending to 48 hours for a period of five days. The advisories consisted of ``relative`` ash cloud concentrations in ten layers (surface-5,000 feet, 5,000--10,000 feet and every 10,000 feet to 90,000 feet). The ash was represented as a log-normal size distribution of 10--200 {mu}m diameter solid particles. Size-dependent ``ashfall`` was simulated over time as the eruption clouds dispersed. Except for an internal experimental attempt to model one of the Mount Redoubt, Alaska, eruptions (12/89), ARAC had no prior experience in modeling volcanic eruption ash hazards. For the cataclysmic eruption of 15--16 June, the complex three-dimensional atmospheric structure of the region produced dramatically divergent ash cloud patterns. The large eruptions (> 7--10 km) produced ash plume clouds with strong westward transport over the South China Sea, Southeast Asia, India and beyond. The low-level eruptions (< 7 km) and quasi-steady-state venting produced a plume which generally dispersed to the north and east throughout the support period. Modeling the sequence of eruptions presented a unique challenge. Although the initial approach proved viable, further refinement is necessary and possible. A distinct need exists to quantify eruptions consistently such that ``relative`` ash concentrations relate to specific aviation hazard categories.

  15. Influence of fly ash fineness on water requirement and shrinkage of blended cement mortars

    Directory of Open Access Journals (Sweden)

    Vanissorn Vimonsatit

    2015-12-01

    Full Text Available In this paper, the influence of fly ash fineness on water requirement and shrinkage of blended cement mortar was studied. The results indicate that the water requirement and shrinkage characteristic of the blended cement mortar are dependent on fly ash fineness and replacement level. The use of coarse fly ash slightly reduces the water requirement but greatly reduced the drying and the autogenous shrinkage of the blended cement mortars and the reduction is more with an increase in the fly ash replacement level. The finer fly ashes further reduce the water requirement, but increase the drying and the autogenous shrinkages as compared with coarser fly ash. The incorporation of superplasticizer drastically reduces the water requirement, but the effect on the drying and autogenous shrinkages of the normal Portland cement mortar is small. However, for the fly ash mortar, the use of superplasticizer results in a decrease in drying shrinkage and in a substantial increase in the autogenous shrinkage particularly for the fine fly ash at a high replacement level.

  16. Effects of banana peel-ash-extract on cooking time and acceptability ...

    African Journals Online (AJOL)

    Banana peel ash-extract, widely used in indigenous processing of dry beans, was evaluated for chemical composition and potential in reducing cooking time of beans with HTC defect. The peel ash-extract was found to contain substantial amounts of sodium (0.36 g/ml), chloride (0.07 g/ml) and magnesium (0.04g/ml) ions.

  17. Fusion characterization of biomass ash

    DEFF Research Database (Denmark)

    Ma, Teng; Fan, Chuigang; Hao, Lifang

    2016-01-01

    The ash fusion characteristics are important parameters for thermochemical utilization of biomass. In this research, a method for measuring the fusion characteristics of biomass ash by Thermo-mechanical Analyzer, TMA, is described. The typical TMA shrinking ratio curve can be divided into two...... stages, which are closely related to ash melting behaviors. Several characteristics temperatures based on the TMA curves are used to assess the ash fusion characteristics. A new characteristics temperature, Tm, is proposed to represent the severe melting temperature of biomass ash. The fusion...... characteristics of six types of biomass ash have been measured by TMA. Compared with standard ash fusibility temperatures (AFT) test, TMA is more suitable for measuring the fusion characteristics of biomass ash. The glassy molten areas of the ash samples are sticky and mainly consist of K-Ca-silicates....

  18. Melting and Sintering of Ashes

    DEFF Research Database (Denmark)

    Hansen, Lone Aslaug

    1997-01-01

    -1300°C, and a trend of higher fusion temperatures with increasing contents of Al-silicates and quartz was found.c) Fly ashes, bottom ashes and deposits from coal/straw co-firing were all found to consist mainly of metal-alumina and alumina-silicates. These ashes all melt in the temperature range 1000......The thesis contains an experimental study of the fusion and sintering of ashes collected during straw and coal/straw co-firing.A laboratory technique for quantitative determination of ash fusion has been developed based on Simultaneous Thermal Analysis (STA). By means of this method the fraction......, the biggest deviations being found for salt rich (i.e. straw derived) ashes.A simple model assuming proportionality between fly ash fusion and deposit formation was found to be capable of ranking deposition rates for the different straw derived fly ashes, whereas for the fly ashes from coal/straw co-firing...

  19. Enhancing the engineering properties of expansive soil using bagasse ash

    Science.gov (United States)

    Silmi Surjandari, Niken; Djarwanti, Noegroho; Umri Ukoi, Nafisah

    2017-11-01

    This paper deals with stabilization of expansive soil on a laboratory experimental basis. The aim of the research was to evaluate the enhancement of the engineering properties of expansive soil using bagasse ash. The soil is treated with bagasse ash by weight (0, 5, 10, 15, and 20%) based on dry mass. The performance of bagasse ash stabilized soil was evaluated using physical and strength performance tests, namely the plasticity index, standard Proctor compaction, and percentage swelling. An X-ray diffraction (XRD) test was conducted to evaluate the clay mineral, whereas an X-ray fluorescence (XRF) was to the chemical composition of bagasse ash. From the results, it was observed that the basic tests carried out proved some soil properties after the addition of bagasse ash. Furthermore, the plasticity index decreased from 53.18 to 47.70%. The maximum dry density of the specimen increased from 1.13 to 1.24 gr/cm3. The percentage swelling decreased from 5.48 to 3.29%. The outcomes of these tests demonstrate that stabilization of expansive soils using bagasse ash can improve the strength.

  20. Trends in domestic and international markets for ash logs and lumber

    Science.gov (United States)

    Dan. Meyer

    2010-01-01

    While ash is a "minor" commercial hardwood species relative to oak, poplar, and maple, it still accounts for roughly 3 percent of all hardwood lumber produced, with an estimated kiln-dried value exceeding $150 million annually.

  1. Effect of rice husk ash on some geotechnical properties of lateritic

    African Journals Online (AJOL)

    hp

    Keywords: Rice Husk Ash (RHA), Lateritic soil, Sub-grade, Maximum Dry ... stabilizing agent (cement or lime) included ... soil and then with distilled water. The clay mineral identification was done using ... California Bearing Ratio (CBR). 22.05.

  2. Composition and reactivity of ash from sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Willems, M; Pedersen, B; Jorgensen, S S

    1976-01-01

    Sewage sludge and sludge ash produced at 450 to 1050/sup 0/C in the laboratory or in a multiple hearth incinerator were analyzed by chemical and X-ray diffraction methods. Among the ash components were 23 to 32 percent calcium and magnesium phosphates and the following percentages of heavy metals: Zn 0.9, Cu 0.2, Pb 0.1, Cr 0.07, Ni 0.02, and Cd 0.006. As shown by EDTA-extraction, the reactivity of heavy metals was higher in ash produced at 450/sup 0/C than in dry sludge, but lower in ash produced above 800/sup 0/C. Phosphate in the 800 to 900/sup 0/C samples was dissolved in citric acid but not in citrate.

  3. Ashes to ashes: Large Fraxinus germplasm collections and their fates

    Science.gov (United States)

    Kim C. Steiner; Paul. Lupo

    2010-01-01

    As the emerald ash borer (EAB) threatens the survival of our ash species, measures should be taken to preserve their genetic variability in the event that we discover a way to restore populations destroyed by the beetle. As it happens, large germplasm collections exist for our most important and widely distributed eastern species of the genus, white ash (...

  4. Effect of Rice Husk Ash on Cement Stabilized Laterite

    OpenAIRE

    Musa ALHASSAN; Alhaji Mohammed MUSTAPHA

    2007-01-01

    Laterite soil collected from Maikunkele area of Minna, classified as an A-7-6 on AASHTO classification, was stabilized with 2-8% cement by weight of the dry soil. Using British Standard Light (BSL) compaction energy, the effect of Rice Husk Ash (RHA) on the soil was investigated with respect to compaction characteristics, California Bearing Ratio (CBR) and Unconfined Compressive Strength (UCS) tests. Results obtained, indicate a general decrease in Maximum Dry Density (MDD) and increase in Op...

  5. Dry Eye

    Science.gov (United States)

    ... Eye » Facts About Dry Eye Listen Facts About Dry Eye Fact Sheet Blurb The National Eye Institute (NEI) ... and their families search for general information about dry eye. An eye care professional who has examined the ...

  6. Drying kinetic and physical properties of green laird lentil (Lens ...

    African Journals Online (AJOL)

    AMAJU

    2011-05-09

    May 9, 2011 ... features crude protein, oil and ash parameters were specified under different microwave levels. It was concluded ..... Microwave processing of avocado: Volatile flavor profiling and ... microwave drying of garlic cloves. J. Food ...

  7. Ash Properties of Alternative Biomass

    DEFF Research Database (Denmark)

    Capablo, Joaquin; Jensen, Peter Arendt; Pedersen, Kim Hougaard

    2009-01-01

    analysis into three main groups depending upon their ash content of silica, alkali metal, and calcium and magnesium. To further detail the biomass classification, the relative molar ratio of Cl, S, and P to alkali were included. The study has led to knowledge on biomass fuel ash composition influence...... on ash transformation, ash deposit flux, and deposit chlorine content when biomass fuels are applied for suspension combustion....

  8. Fusion characterization of biomass ash

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Teng [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Sino-Danish Center for Education and Research, Beijing, 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Fan, Chuigang; Hao, Lifang [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Li, Songgeng, E-mail: sgli@ipe.ac.cn [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Song, Wenli [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Lin, Weigang [State Key Laboratory ofMultiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 Zhongguancun North Second Street, Beijing 100190 (China); Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

    2016-08-20

    Highlights: • A novel method is proposed to analyze fusion characteristics of biomass ash. • T{sub m} can represent the severe melting temperature of biomass ash. • Compared with AFT, TMA is the better choice to analyze the fusion characteristics of biomass ash. - Abstract: The ash fusion characteristics are important parameters for thermochemical utilization of biomass. In this research, a method for measuring the fusion characteristics of biomass ash by Thermo-mechanical Analyzer, TMA, is described. The typical TMA shrinking ratio curve can be divided into two stages, which are closely related to ash melting behaviors. Several characteristics temperatures based on the TMA curves are used to assess the ash fusion characteristics. A new characteristics temperature, T{sub m}, is proposed to represent the severe melting temperature of biomass ash. The fusion characteristics of six types of biomass ash have been measured by TMA. Compared with standard ash fusibility temperatures (AFT) test, TMA is more suitable for measuring the fusion characteristics of biomass ash. The glassy molten areas of the ash samples are sticky and mainly consist of K-Ca-silicates.

  9. Potential use of fly ash to soil treatment in the Morava region

    Science.gov (United States)

    Bulíková, Lucia; Kresta, František; Rochovanský, Martin

    2017-09-01

    Soil treatment by binders is a standard technology and leads to optimal utilization of excavated soils in road constructions. Soil treatment is controlled in the Czech Republic by EN 14227-15 and Technical Requirement TP 94. Soil treatment using fly ash has not been performed in the Czech Republic, although there is a sufficient normative base. Fly ash produced by burning of hard coal in the Moravian region was tested as a potential binder. Fly ash samples were mixed with loess loams (CI). Tested siliceous fly ash of class F (ASTM C618) did not showed hydraulic properties but it showed positive effect on reducing maximum dry density of mixtures, increasing the IBI value (Immediate bearing index) and decreasing tendency to volume changes when the amount of fly ash was increased. The results of laboratory tests demonstrate the possibility of using fly ashes as a binder for soil treatment.

  10. Lunar ash flows - Isothermal approximation.

    Science.gov (United States)

    Pai, S. I.; Hsieh, T.; O'Keefe, J. A.

    1972-01-01

    Suggestion of the ash flow mechanism as one of the major processes required to account for some features of lunar soil. First the observational background and the gardening hypothesis are reviewed, and the shortcomings of the gardening hypothesis are shown. Then a general description of the lunar ash flow is given, and a simple mathematical model of the isothermal lunar ash flow is worked out with numerical examples to show the differences between the lunar and the terrestrial ash flow. The important parameters of the ash flow process are isolated and analyzed. It appears that the lunar surface layer in the maria is not a residual mantle rock (regolith) but a series of ash flows due, at least in part, to great meteorite impacts. The possibility of a volcanic contribution is not excluded. Some further analytic research on lunar ash flows is recommended.

  11. Evaluation of added phosphorus in six volcanic ash soils

    International Nuclear Information System (INIS)

    Pino N, I.; Casas G, L.; Urbinsa P, M.C.

    1984-01-01

    The behaviour of added phosphorus in six volcanic ash soils (Andepts) was studied. Two phosphate retention solution were used; one of them labeled with 32 P carrier free. The phosphate retention solution (25 ml) was added to 5 gr of air dry soil. The remainder phosphorus in solution was measured through colorimetry and liquid scintillation. Over 85% phosphorus retention was measured in five soils. A phosphate retention solution labeled with 32 P carrier free proved to be efficient for the determination of phosphorus retention rates in the volcanic ash soils studied. (Author)

  12. Soybean growth on fly ash-amended strip mine soils

    Energy Technology Data Exchange (ETDEWEB)

    Fail, Jr, J L; Wochok, Z S

    1977-01-01

    The use of fly ash as an amendment for strip mine soils has been studied under field conditions. Soils ranging in pH from 4.0 to 6.0 were tested. The addition of fly ash in all cases was effective as an acid soil neutralizer and substantially enhanced the growth and development of all experimental plants. The parameters used in growth analyses were plant height, dry weight, root/shoot ratios, nodulation, pod production, and nitrogen fixing capacity for legumes.

  13. Ash dust co-centration in the vicinity of the ash disposal site depending on the size of the pond (“Water Mirror”

    Directory of Open Access Journals (Sweden)

    Zoran Gršić

    2010-09-01

    Full Text Available Thermal power plants Nikola Tesla “A” and “B” are large sources of ash from their ashes/slag deposit sites. Total sizes of ashes/slag depots are 600ha and 382ha, with active cassettes having dimensions ∼200 ha and ∼130 ha. The active cassettes of the disposal sites are covered by rather large waste ponds, the sizes of vary depending on the working condition of a sluice system and on meteorological conditions. Modeling of ash lifting was attempted using results from the dust lifting research. The relation between sizes of ponds and air dust concentration in the vicinity of ash disposal sites was analyzed. As expected, greater sizes of dried disposal site surfaces in combination with stronger winds gave greater dust emission and greater air dust concentration.

  14. Incineration ash conditioning processes

    International Nuclear Information System (INIS)

    Jouan, A.; Ouvrier, N.; Teulon, F.

    1990-01-01

    Incinerable wastes consist of the following standard composition corresponding to projected wastes from a future mixed oxide fuel fabrication plant with an annual throughput of 1700 kg (i.e. 5.7 m 3 ) of ashes produced by the incineration facility: . 50% polyvinyl chloride (glove box sleeves), . 5% polyethylene (bags), . 35% rubber (equal amounts of latex and neoprene), . 10% cellulose (equal amounts of cotton and cleansing tissues). The work focused mainly on compaction by high-temperature isostatic pressing, is described in some detail with the results obtained. An engineering study was also carried out to compare this technology with two other ash containment processes: direct-induction (cold crucible) melting and cement-resin matrix embedding. Induction melting is considerably less costly than isostatic pressing; the operating costs are about 1.5 times higher than for cement-resin embedding, but the volume reduction is nearly 3 times greater

  15. Photosynthetic pigment concentrations, gas exchange and vegetative growth for selected monocots and dicots treated with two contrasting coal fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Yunusa, I.A.M.; Burchett, M.D.; Manoharan, V.; DeSilva, D.L.; Eamus, D.; Skilbeck, C.G. [University of Technology Sydney, Sydney, NSW (Australia). Dept. of Environmental Science

    2009-07-15

    There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hyothesis that photosynthetic pigments concentrations and CO{sub 2} assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organization for Economic Cooperation and Development (OECD) to monocots (barley (Hordeum vulgare) and ryegrass (Secale cereale)) and dicots (canola (Brasica napus), radish (Raphanus sativus), field peas (Pisum sativum), and lucerne (Medicago sativa)) on media amended with fly ashes derived from semi-bituminous (gray ash) or lignite (red ash) coals at rates of 0, 2.5, 5.0, 10, or 20 Mg ha(-1). The red ash had higher elemental concentrations and salinity than the gray ash. Fly ash addition had no significant effect on germination by any of the six species. At moderate rates ({<=}10 Mg ha{sup -1}) both ashes increased (P < 0.05) growth rates and concentrations of chlorophylls a and b, but reduced carotenoid concentrations. Addition of either ash increased A in radish and transpiration in barley. Growth rates and final dry weights were reduced for all of the six test species when addition rates exceeded 10 Mg ha{sup -1} for gray ash and 5 Mg ha{sup -1} for red ash. We concluded that plant dry weights, rather than pigment concentrations and/or instantaneous rates of photosynthesis, are more consistent for assessing subsequent growth in plants supplied with fly ash.

  16. Mechanism research on coupling effect between dew point corrosion and ash deposition

    International Nuclear Information System (INIS)

    Wang, Yun-Gang; Zhao, Qin-Xin; Zhang, Zhi-Xiang; Zhang, Zhi-Chao; Tao, Wen-Quan

    2013-01-01

    In order to study the coupling mechanism between ash deposition and dew point corrosion, five kinds of tube materials frequently used as anti-dew point corrosion materials were selected as research objects. Dew point corrosion and ash deposition experiments were performed with a new type experimental device in a Chinese thermal power plant. The microstructures of the materials and the composition of ash deposition were analyzed by X-ray diffraction (XRD) and Energy Dispersive Spectrometer (EDS). The results showed that the ash deposition layer could be divided into non-condensation zone, the main condensation zone and the secondary condensation zone. The acid vapor condensed in the main condensation zone rather than directly on the tube wall surface. The dew point corrosion mainly is oxygen corrosion under the condition of the viscosity ash deposition, and the corrosion products are composed of the ash and acid reaction products in the outer layer, iron sulfate in the middle layer, and iron oxide in the inner layer. The innermost layer is the main corrosion layer. With the increase of the tube wall temperature, the ash deposition changes from the viscosity ash deposition to the dry loose ash deposition, the ash deposition rate decreases dramatically and dew point corrosion is alleviated efficiently. The sulfuric dew point corrosion resistance of the five test materials is as follows: 316L > ND > Corten>20G > 20 steel. -- Highlights: ► Dew point corrosion and ash deposition tests of five materials were performed. ► Acid vapor condensed in the ash deposit rather than directly on the tube surface. ► Dew point corrosion resistance is as follow: 316L > ND > Corten>20G > 20 steel. ► Dew point corrosion mainly is oxygen corrosion under viscosity ash deposition

  17. Strength and Compaction Analysis of Sand-Bentonite-Coal Ash Mixes

    Science.gov (United States)

    Sobti, Jaskiran; Singh, Sanjay Kumar

    2017-08-01

    This paper deals with the strength and compaction characteristics of sand-bentonite-coal ash mixes prepared by varying percentages of sand, bentonite and coal ash to be used in cutoff walls and as a liner or cover material in landfills. The maximum dry density (MDD) and optimum moisture content (OMC) of sand-bentonite mixes and sand-bentonite-coal ash mixes were determined by conducting the standard proctor test. Also, the strength and stiffness characteristics of soil mixes were furnished using unconfined compressive strength test. The results of the study reveal influence of varying percentages of coal ash and bentonite on the compaction characteristics of the sand-bentonite-coal ash mixes. Also, validation of a statistical analysis of the correlations between maximum dry density (MDD), optimum moisture content (OMC) and Specific Gravity (G) was done using the experimental results. The experimental results obtained for sand-bentonite, sand-bentonite-ash and coal ash-bentonite mixes very well satisfied the statistical relations between MDD, OMC and G with a maximum error in the estimate of MDD being within ±1 kN/m3. The coefficient of determination (R2) ranged from 0.95 to 0.967 in case of sand-bentonite-ash mixes. However, for sand-bentonite mixes, the R2 values are low and varied from 0.48 to 0.56.

  18. Effect of class F fly ash on the durability properties of concrete

    Directory of Open Access Journals (Sweden)

    Ashish Kumer Saha

    2018-01-01

    Full Text Available The present study evaluates the application of class F fly ash as a partial replacement of binder in concrete. The compressive strength of the fly ash samples showed low early compressive strength comparing to the control samples. However, due to pozzolanic reaction strength was improved gradually over a longer period of time, whereas control samples stopped the strength growth after 56-d of curing. The drying shrinkage was reduced with the increment of fly ash content in the mix. The inclusion of fly ash as a binder reduced the porosity of the concrete. As a result, the fly ash concrete exhibited lower water sorptivity and chloride permeability. Furthermore, a significant drop of sorptivity and chloride permeability was observed for fly ash concrete between the curing period of 28–180 days. Microstructural morphology of fly ash samples was investigated to evaluate the reason behind the improved durability characteristics. Keywords: Fly ash, Compressive strength, Drying shrinkage, Permeable void, Water sorptivity, Chloride permeability

  19. Experimental study on durability improvement of fly ash concrete with durability improving admixture.

    Science.gov (United States)

    Quan, Hong-zhu; Kasami, Hideo

    2014-01-01

    In order to improve the durability of fly ash concrete, a series of experimental studies are carried out, where durability improving admixture is used to reduce drying shrinkage and improve freezing-thawing resistance. The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on the performance of fly ash concrete are discussed in this paper. The results show that by using durability improving admixture in nonair-entraining fly ash concrete, the compressive strength of fly ash concrete can be improved by 10%-20%, and the drying shrinkage is reduced by 60%. Carbonation resistance of concrete is roughly proportional to water-cement ratio regardless of water-binder ratio and fly ash replacement ratio. For the specimens cured in air for 2 weeks, the freezing-thawing resistance is improved. In addition, by making use of durability improving admixture, it is easier to control the air content and make fly ash concrete into nonair-entraining one. The quality of fly ash concrete is thereby optimized.

  20. Evaluation of Changes in Index Properties of Lateritic Soil Stabilized with Fly Ash

    Directory of Open Access Journals (Sweden)

    Agapitus AMADI

    2010-12-01

    Full Text Available For soils to be suitable in civil engineering projects, they must meet existing local requirements for index properties in addition to certain strength criteria. Typically, specifications limit these properties to some threshold values which in most cases are project specific. Some lateritic soils in their natural state need some treatment/modification to meet these specification requirements. The objective of this study was to evaluate changes in the index properties (i.e., particle size distribution, Atterberg limits and compaction characteristics of a residually derived lateritic soil following fly ash application. Lateritic soil – fly ash mixtures with up to 20% fly ash by dry weight of soil were tested and specimens for compaction characteristics were prepared at different compaction states (optimum, dry and wet of optimum moisture content and compacted using British Standard Light (BSL compactive effort. While soil – fly ash mixtures containing up to 15% fly ash classify as CL according to USCS classification system and plotted above A-line in the plasticity chart, it was observed that changes in the gradation characteristics of soil sample treated with 20% fly ash resulted in the alteration of its classification to ML as well as the crossing of the A- line to the silty region. The liquid limit (LL varied from 42.2 to 29.53% representing 70% reduction while the plasticity index (PI of specimen treated with 20% fly ash was 16% lower than that of natural soil. The optimum moisture content (OMC ranged from 17.36% for the natural soil to 18.34% for soil mixtures containing 20% fly ash which yielded dry unit weight of 17.2kN/m3 for the natural soil and 16.1kN/m3 for samples treated with 20% fly ash. From the study, useful data were obtained showing substantial and desirable changes in the properties of lateritic soil as a civil engineering material on application of fly ash.

  1. Dry socket

    Science.gov (United States)

    Alveolar osteitis; Alveolitis; Septic socket ... You may be more at risk for dry socket if you: Have poor oral health Have a ... after having a tooth pulled Have had dry socket in the past Drink from a straw after ...

  2. An improved ashing procedure for biologic sample

    Energy Technology Data Exchange (ETDEWEB)

    Zongmei, Wu [Zhejiang Province Enviromental Radiation Monitoring Centre (China)

    1992-07-01

    The classical ashing procedure in muffle was modified for biologic samples. In the modified procedure the door of muffle was open in the duration of ashing process, the ashing was accelerated and the ashing product quality was comparable to that the classical procedure. The modified procedure is suitable for ashing biologic samples in large batches.

  3. An improved ashing procedure for biologic sample

    International Nuclear Information System (INIS)

    Wu Zongmei

    1992-01-01

    The classical ashing procedure in muffle was modified for biologic samples. In the modified procedure the door of muffle was open in the duration of ashing process, the ashing was accelerated and the ashing product quality was comparable to that the classical procedure. The modified procedure is suitable for ashing biologic samples in large batches

  4. Classification of pulverized coal ash

    International Nuclear Information System (INIS)

    Van der Sloot, H.A.; Van der Hoek, E.E.; De Groot, G.J.; Comans, R.N.J.

    1992-09-01

    The leachability of fifty different pulverized coal ashes from utilities in the Netherlands, Federal Republic of Germany and Belgium has been studied. Five different ashes were analyzed according to the complete standard leaching test and the results were published earlier. The examination of a wide variety of ashes under a wide range of pH and Liquid to Solid ratio (LS) conditions creates the possibility of identifying systematic trends in fly ash leaching behaviour and to identify the mechanisms controlling release. 16 figs., 2 tabs., 3 app., 25 refs

  5. Publication sites productive uses of combustion ash

    Science.gov (United States)

    Publication Sites Productive Uses of Combustion Ash For more information contact: e:mail: Public waste combustion ash in landfills. The new technology brief describes recent studies where ash was used

  6. Can ash clog soil pores?

    Science.gov (United States)

    Stoof, Cathelijne; Stoof, Cathelijne; Gevaert, Anouk; Gevaert, Anouk; Baver, Christine; Baver, Christine; Hassanpour, Bahareh; Hassanpour, Bahareh; Morales, Veronica; Morales, Veronica; Zhang, Wei; Zhang, Wei; Martin, Deborah; Martin, Deborah; Steenhuis, Tammo; Steenhuis, Tammo

    2015-04-01

    Wildfire can greatly increase a landscape's vulnerability to flooding and erosion events, and ash is thought to play a large role in controlling runoff and erosion processes after wildfire. Although ash can store rainfall and thereby reduce runoff and erosion for a limited period after wildfires, it has also been hypothesized to clog soil pores and reduce infiltration. Several researchers have attributed the commonly observed increase in runoff and erosion after fire to the potential pore-clogging effect of ash. Evidence is however incomplete, as to date, research has solely focused on identifying the presence of ash in the soil, with the actual flow processes associated with the infiltration and pore-clogging of ash remaining a major unknown. In several laboratory experiments, we tested the hypothesis that ash causes pore clogging to the point that infiltration is hampered and ponding occurs. We first visualized and quantified pore-scale infiltration of water and ash in sand of a range of textures and at various infiltration rates, using a digital bright field microscope capturing both photo and video. While these visualization experiments confirm field and lab observation of ash washing into soil pores, we did not observe any clogging of pores, and have not been able to create conditions for which this does occur. Additional electrochemical analysis and measurement of saturated hydraulic conductivity indicate that pore clogging by ash is not plausible. Electrochemical analysis showed that ash and sand are both negatively charged, showing that attachment of ash to sand and any resulting clogging is unlikely. Ash also had quite high saturated conductivity, and systems where ash was mixed in or lying on top of sand had similarly high hydraulic conductivity. Based on these various experiments, we cannot confirm the hypothesis that pore clogging by ash contributes to the frequently observed increase in post-fire runoff, at least for the medium to coarse sands

  7. Fly ash quality and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Barta, L.E.; Lachner, L.; Wenzel, G.B. [Inst. for Energy, Budapest (Hungary); Beer, M.J. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

    1995-12-01

    The quality of fly ash is of considerable importance to fly ash utilizers. The fly ash puzzolanic activity is one of the most important properties that determines the role of fly ash as a binding agent in the cementing process. The puzzolanic activity, however is a function of fly ash particle size and chemical composition. These parameters are closely related to the process of fly ash formation in pulverized coal fired furnaces. In turn, it is essential to understand the transformation of mineral matter during coal combustion. Due to the particle-to-particle variation of coal properties and the random coalescence of mineral particles, the properties of fly ash particles e.g. size, SiO{sub 2} content, viscosity can change considerably from particle to particle. These variations can be described by the use of the probability theory. Since the mean values of these randomly changing parameters are not sufficient to describe the behavior of individual fly ash particles during the formation of concrete, therefore it is necessary to investigate the distribution of these variables. Examples of these variations were examined by the Computer Controlled Scanning Electron Microscopy (CCSEM) for particle size and chemical composition for Texas lignite and Eagel Butte mineral matter and fly ash. The effect of combustion on the variations of these properties for both the fly ash and mineral matter were studied by using a laminar flow reactor. It is shown in our paper, that there are significant variations (about 40-50% around the mean values) of the above-listed properties for both coal samples. By comparing the particle size and chemical composition distributions of the mineral matter and fly ash, it was possible to conclude that for the Texas lignite mineral matter, the combustion did not effect significantly the distribution of these properties, however, for the Eagel Butte coal the combustion had a major impact on these mineral matter parameters.

  8. Coal ash monitoring equipment

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, C G; Wormald, M R

    1978-10-02

    The monitoring equipment is used to determine the remainder from combustion (ash slack) of coal in wagons designed for power stations. Next to the rails, a neutron source (252 Cf, 241 Am/Be) is situated, which irradiates the coal with neutrons at a known dose, which produces the reaction 27 Al (n ..gamma..) Al 28. The aluminium content is a measure of the remainder. The 1.78 MeV energy is measured downstream of the rail with a detector. The neutron source can only act in the working position of a loaded wagon.

  9. Measurement of natural activity in peat ashes

    International Nuclear Information System (INIS)

    Suomela, J.

    1985-01-01

    High proportions of radioactive materials in peat ashes may involve radiation hazards during handling and deposition of these waste materials. Measurements have been performed to determine the content of radioactive materials in ashes from peat burning. The activities in fly ash and ''solid'' ash in seven peat-fired power plants in Sweden are presented. The methods of analysing and measuring peat ashes for activity from different radionuclides are described. The activity levels in ash samples are given

  10. Stabilization of soft clayey soils with sawdust ashes

    Directory of Open Access Journals (Sweden)

    Karim Hussein

    2018-01-01

    Full Text Available The problems of soft clayey soils are taken in considerations by many Iraqi geologists and civil engineers, because about 35% of the Iraqi clay soils (especially southern Iraq are weak. Thus, it is necessary to improve the properties of such soils for road construction by means of using of various stabilizers such as sawdust ash. The main goal of the present study is to stabilize soft clay models with sawdust ash (SDA additive using different percentages (0, 2, 4, 6, 8 and 10% by dry weight of soil. The results revealed that the additive has adverse effects on the property of soil indices by increasing its liquid limit and plasticity index due to clay content. The mixture of sawdust ashes with soft clay soils improves most other physical and mechanical properties of the soil, as expressed by a general reduction in specific gravity and maximum dry density (MDD, as well as a reduction in the compression coefficients (Cc and Cr with an increase in SDA content. While increasing the optimum moisture content (OMC and the undrained shear strength (cu with the increase in SDA content. The stabilized soils (with 4 and 10% ash content resulted in low CBR values (1.6-1.2% which can be used as sub-base. The SDA can be considered as a cheap and acceptable stabilizing agent in road construction for improving most of the geotechnical properties of the soft clayey soil.

  11. Emerald ash borer flight potential

    Science.gov (United States)

    Robin A. Taylor; Leah S. Bauer; Deborah L. Miller; Robert A. Haack

    2005-01-01

    The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive pest of ash trees (Fraxinus spp.) that is rapidly spreading from the probable introduction site in Detroit, Michigan. The rapid spread to areas outside Michigan is undoubtedly due to phoretic transport on nursery stock, logs, and...

  12. Prospects for ash pond reclamation

    Energy Technology Data Exchange (ETDEWEB)

    Shyyam, A.K.; Shukla, K.S.; Agrawal, D. (National Thermal Power Corporation Ltd., New Delhi (India))

    1993-01-01

    A typical modern coal fired station in India burns 0.7 t/MWh of coal and consequently generates ash at 0.245 t/MWh. The physical nature of ash, low available concentrations of certain plant nutrients and the presence of phytotoxic trace elements render fly ash marginally adequate for plant growth. As fly ash itself was thought to be an inappropriate growth medium for plants, regulators decided that a soil cover is mandatory. There is ample data to suggest that the attributes of fly ash detrimental to plant growth can be ameliorated, allowing the establishment of vegetation directly on fly ash surfaces. The natural revegetation of fly ash disposal sites has been reported in the world. The natural vegetation pioneered by Cynodon at different stages of ecological succession and comprising of species such as [ital Calotropis gigantea], [ital Lippia nodiflora], [ital Ipomea, cornea], [ital Xanthium parviflorum] has been noted at one of the NTPC projects, in Badarpur Thermal Power Station. Since natural reclamation is a time-consuming process, experimental trials of growing some species over the temporary ash lagoon directly (without soil cover) were carried out at Ramagundam Super Thermal Power Project (RSTPP) of NTPC, in South India to achieve faster results than the natural process. 6 refs., 8 figs.

  13. Emerald ash borer life cycle

    Science.gov (United States)

    Leah S. Bauer; Robert A. Haack; Deborah L. Miller; Toby R. Petrice; Houping Liu

    2004-01-01

    The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), native to several Asian countries, was discovered in southeastern Michigan and nearby Ontario in June of 2002. EAB was identified as the cause of extensive ash (Fraxinus spp.) mortality in approximately 2,500 mi2, and...

  14. Leaching from biomass combustion ash

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard

    2014-01-01

    The use of biomass combustion ashes for fertilizing and liming purposes has been widely addressed in scientific literature. Nevertheless, the content of potentially toxic compounds raises concerns for a possible contamination of the soil. During this study five ash samples generated at four...

  15. Plant growth on 'fly ash'

    Energy Technology Data Exchange (ETDEWEB)

    Holliday, R; Hodgson, D R; Townsend, W N; Wood, J W

    1958-04-12

    Plants were grown in plot and pot experiments to assess the toxicity of the fly ash. It was found that plants grouped into three classes: tolerant, moderately tolerant, and sensitive. Boron was found to be a major compoent of the toxic principle of fly ash.

  16. Emerald ash borer biological control

    Science.gov (United States)

    Leah Bauer; Juli Gould; Jian Duan; Mike. Ulyshen

    2011-01-01

    Emerald ash borer (EAB) (Agrilus planipennis), an invasive buprestid from northeast Asia, was identified in 2002 as the cause of ash (Fraxinus) tree mortality in southeast Michigan and adjacent areas of Ontario, Canada. This destructive beetle apparently arrived in North America via infested solid wood packaging materials from...

  17. Emerald Ash Borer (Coleoptera: Buprestidae)

    Science.gov (United States)

    The emerald ash borer, Agrilus planipennis Fairmaire, is an invasive beetle from Asia that has caused large scale ash (Fraxinus spp.) mortality in North America. This book chapter reviews the taxonomy, biology, life history of this invasive pest and its associated natural enemies in both its native ...

  18. ECOLOGICAL AND TECHNOLOGYCAL ASPECTS OF ASH AND SLAG WASTES UTILIZATION

    Directory of Open Access Journals (Sweden)

    Tatyana Aleksandrova

    2017-07-01

    Full Text Available The article presents the results of investigation focused on the utilization of ash and slag wastes (ASW in Russia including investigation of chemical and physical properties of ASW and processing products. Many factors influence the technological properties of ash and slag materials: naturals, processes and environments. The integrated treatment of ash and slag wastes of both stored and re-formed types will allow obtaining the following commercial products: coal concentrate, iron concentrate, aluminosilicate cenospheres, aluminosilicate product. In this study we have analyzed the methods for separation of ASW iron-containing part using the different types of the magnetic separation from the ash and slag material from one of the combined heat and power plant (CHPP in the Russian Far East Federal District. The greatest interest is the dry magnetic separation with travelling electromagnetic field. The subject of research was a sample taken from one of ash dump of CHPP in the Far East. In the study iron concentrate containing Fetotal = 64% was obtained recovery 68% in the low intensity (up to 5 kOe travelling magnetic field.

  19. An efficient and not polluting bottom ash extraction system

    International Nuclear Information System (INIS)

    Carrea, A.

    1992-01-01

    This paper reports that boiler waste water effluent must meet more and more tighter requirements to comply with environmental regulations; sluice water resulting from bottom ash handling is one of the main problems in this context, and many utilities are under effort to maximize the reuse of the sluice water, and, if possible, to meet the aim of zero water discharge from bottom ash handling system. At the same time ash reuse efforts gain strength in order to minimize waste production. One solution to these problems can be found in an innovative Bottom Ash Extraction System (MAC System), marked by the peculiarity to be a continuous dry ash removal; the system has been developed in the last four years by MAGALDI INDUSTRIE SRL in collaboration with ANSALDO Ricerche, the R and D department of ANSALDO, the main Italian Boiler Manufacturer, and is now installed in six ENEL Boilers. The elimination of the water as separation element between the bottom part of the furnace and the outside atmosphere gives advantages mainly from the environmental view point, but a certain improvement in the boiler efficiency has also been demonstrated by the application of the system

  20. Steam gasification of Bulmer coal in the presence of lignite ash

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A.; Furimsky, E.

    1986-01-01

    Steam gasification of blends prepared from Balmer coal and the ash from combustion of Onakawana lignite was performed in a fixed bed reactor. The blends were prepared by co-slurrying followed by drying. In the presence of 20 wt% ash the gasification rate doubled at 830 and 930 C. Direct blending of coal and lignite resulted in an overall increase in carbon conversion at 830 C but had no effect at 930 C. 5 refs.

  1. Wood ash treatment, a cost-effective way to deactivate tannins in Acacia cyanophylla Lindl. foliage and to improve digestion by Barbarine sheep

    Energy Technology Data Exchange (ETDEWEB)

    Ben Salem, H. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)]. E-mail: bensalem.hichem@iresa.agrinet.tn; Abidi, S. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Ecole Superieure d' Agriculture de Mateur, Mateur (Tunisia); Makkar, H.P.S. [Animal Production and Health Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna (Austria); Nefzaoui, A. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)

    2005-08-19

    Three in vitro experiments and one in vivo experiment were carried out to study the effect of wood ash sources (6 L wood ash solution/kg fresh plant leaves) and levels and treatment duration on the nutritive value of acacia leaves. In Experiment 1, samples of fresh (F), dried (D), or dried and ground (DG) acacia were soaked for 6 h in water or acacia wood ash solution (120 g of wood ash dry matter/L of water). Soaking acacia in water decreased total extractable phenols (TP), total extractable tannins (TT) and extractable condensed tannins (CT). Wood ash treatment led to a further decrease of these phenolic compounds and was highest with DG acacia. Experiment 2 investigated different levels of acacia wood ash (0, 120, 180 and 240 g wood ash dry matter/L of water) and treatment duration (1, 2 and 3 days). The higher the level of wood ash, the lower proportion of TP and CT in acacia was noted. In Experiment 3, two sources of wood ash (i.e., acacia and Aleppo pine) and the same solution of each source of wood ash were used eight times. The two sources of wood ash had similar deactivating effect on TP and CT. The rate of decrease of TP and CT was highest when the same wood ash solution was used four consecutive times and decreased progressively thereafter. In these three experiments, water and wood ash treatment reduced organic matter and crude protein content but substantially increased the neutral detergent fibre (NDFom) content of treated acacia. In the fourth experiment, we treated acacia with acacia wood ash (180 g/L of water for 2 days) and the same solution was used five times. Treated and untreated acacia were air-dried and fed ad libitum to two groups, each of four Barbarine rams together with 300 g of concentrate. Wood ash treatment did not affect intake and OM digestibility of the diet but increased crude protein and NDFom digestibility (P < 0.05). Feeding untreated acacia resulted in negative N balances but with wood ash treatment, N balance was positive

  2. Dry Etching

    DEFF Research Database (Denmark)

    Stamate, Eugen; Yeom, Geun Young

    2016-01-01

    generation) to 2,200 × 2,500 mm (eighth generation), and the substrate size is expected to increase further within a few years. This chapter aims to present relevant details on dry etching including the phenomenology, materials to be etched with the different recipes, plasma sources fulfilling the dry...

  3. The Effect of Alkaline Activator Ratio on the Compressive Strength of Fly Ash-Based Geopolymer Paste

    Science.gov (United States)

    Lăzărescu, A. V.; Szilagyi, H.; Baeră, C.; Ioani, A.

    2017-06-01

    Alkaline activation of fly ash is a particular procedure in which ash resulting from a power plant combined with a specific alkaline activator creates a solid material when dried at a certain temperature. In order to obtain desirable compressive strengths, the mix design of fly ash based geopolymer pastes should be explored comprehensively. To determine the preliminary compressive strength for fly ash based geopolymer paste using Romanian material source, various ratios of Na2SiO3 solution/ NaOH solution were produced, keeping the fly ash/alkaline activator ratio constant. All the mixes were then cured at 70 °C for 24 hours and tested at 2 and 7 days, respectively. The aim of this paper is to present the preliminary compressive strength results for producing fly ash based geopolymer paste using Romanian material sources, the effect of alkaline activators ratio on the compressive strength and studying the directions for future research.

  4. The effect of using different sources of dry materials on waste-form grout properties

    International Nuclear Information System (INIS)

    Spence, R.D.; Gilliam, T.M.; McDaniel, E.W.

    1992-01-01

    A reference grout formulation had been developed for a liquid low-level radioactive waste using the following dry materials: ground limestone, ground granulated blast furnace slag, fly ash, and cement. The effect of varying the sources of these dry materials are tested. Two limestones, two fly ashes, two cements, and eight slags were tested. Varying the source of dry materials significantly affected the grout properties, but only the 28-d free-standing liquid varied outside of the preferred range. A statistical technique, Tukey's paired comparison, can be used to ascertain whether a given combination of dry materials resulted in grout properties significantly different from those of other combinations of dry materials

  5. Disposal of fly ash

    International Nuclear Information System (INIS)

    Singh, B.; Foley, C.

    1991-01-01

    Theoretical arguments and pilot plant results have shown that the transport of fly-furnace ash from the power station to the disposal area as a high concentration slurry is technically viable and economically attractive. Further, lack of free water, when transported as a high concentration slurry, offers significant advantages in environmental management and rehabilitation of the disposal site. This paper gives a basis for the above observations and discusses the plans to exploit the above advantages at the Stanwell Power Station. (4 x 350 MWe). This will be operated by the Queensland Electricity Commission. The first unit is to come into operation in 1992 and other units are to follow progressively on a yearly basis

  6. To fractionate municipal solid waste incineration bottom ash: Key for utilisation?

    Science.gov (United States)

    Sormunen, Laura Annika; Rantsi, Riina

    2015-11-01

    For the past decade, the Finnish waste sector has increasingly moved from the landfilling of municipal solid waste towards waste incineration. New challenges are faced with the growing amounts of municipal solid waste incineration bottom ash, which are mainly landfilled at the moment. Since this is not a sustainable or a profitable solution, finding different utilisation applications for the municipal solid waste incineration bottom ash is crucial. This study reports a comprehensive analysis of bottom ash properties from one waste incineration plant in Finland, which was first treated with a Dutch bottom ash recovery technique called advanced dry recovery. This novel process separates non-ferrous and ferrous metals from bottom ash, generating mineral fractions of different grain sizes (0-2 mm, 2-5 mm, 5-12 mm and 12-50 mm). The main aim of the study was to assess, whether the advanced bottom ash treatment technique, producing mineral fractions of different grain sizes and therefore properties, facilitates the utilisation of municipal solid waste incineration bottom ash in Finland. The results were encouraging; the bottom ash mineral fractions have favourable behaviour against the frost action, which is especially useful in the Finnish conditions. In addition, the leaching of most hazardous substances did not restrict the utilisation of bottom ash, especially for the larger fractions (>5 mm). Overall, this study has shown that the advanced bottom ash recovering technique can be one solution to increase the utilisation of bottom ash and furthermore decrease its landfilling in Finland. © The Author(s) 2015.

  7. Influence of the Chernobyl accident on radioactivity of fuel peat and peat ash in Finland

    International Nuclear Information System (INIS)

    Mustonen, R.; Salonen, S.; Itkonen, A.

    1988-04-01

    The accident at the Chernobyl nuclear power plant in April 1986 caused very uneven deposition of radionuclides in Finland. The deposited radionuclides were measured in relative high concentrations in fuel peat and especially in peat ash. The radionuclide concentrations were measured at six peat-fired power plants in different parts of Finland throughout the heating season 1986-87. Also evaporation of different radionuclides in peat combustion and their condensation on fly ash particles were studied at four power plants. The 137 Cs-concentrations in compiled peat samples varied between 30 and 3600 Bq kg -1 dry weight and in ash samples between 600 and 68000 Bq kg -1 . Differences in radionuclide concentrations between the power plants were great and also the radionuclide composition in fuel peat varied regionally. The 137 Cs-concentrations of the fly ash after the ash precipitators varied between 12000 and 120000 Bq kg -1 and fly ash emissions varied from 17 to 1100 mg m -3 , depending on the power plant and the load of the boiler. High radioactivity concentrations in precipitator ash caused some restrictions to the utilization of peat ash for various purposes

  8. Technical note: Vetiver can grow on coal fly ash without DNA damage.

    Science.gov (United States)

    Chakraborty, Rajarshi; Mukherjee, Anita

    2011-02-01

    Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to open lands or ash ponds located near power plants and this has lain to waste thousands of hectares all over the world. Wind and leaching are often the causes of off-site contamination from fly ash dumpsites. Vetiver (Vetiveria zizanioides) grown on fly ash for three months showed massive, mesh-like growth of roots which could have a phytostabilizing effect. The plant achieved this without any damage to its nuclear DNA as shown by comet assay done on the root nuclei, which implies the long-term survival of the plant on the remediation site. Also, when Vetiver is used for phytoremediation of coal fly ash, its shoots can be safely grazed by animals as very little of heavy metals in fly ash were found to be translocated to the shoots. These features make planting of Vetiver a practical and environmentally compatible method for restoration of fly ash dumpsites. Lack of DNA damage in Vetiver has been compared to that in a sensitive plant i.e. Allium cepa. Our results suggested that apart from traditional end-points viz. growth parameters like root length, shoot length and dry weight, comet assay could also be included in a battery of tests for initial, rapid and effective selection of plants for restoration and phytoremediation of polluted sites.

  9. Measuring ash content of coal

    International Nuclear Information System (INIS)

    Clayton, C.G.; Wormald, M.R.

    1980-01-01

    An apparatus for measuring the ash content of coal is claimed. It comprises a means for irradiating a known quantity of coal in a transport container with a known dose of neutrons, a means for detecting γ-rays having a predetermined energy emitted by the irradiated coal, the γ-rays being indicative of the presence of an ash-forming element in the coal, a means for producing a signal related to the intensity of the γ-ray emission and a means responsive to the signal to provide an indication of the concentration of the ash-forming element in the coal

  10. Trophic structure and metal bioaccumulation differences in multiple fish species exposed to coal ash-associated metals

    Energy Technology Data Exchange (ETDEWEB)

    Otter, Ryan [Middle Tennessee State University; Bailey, Frank [Middle Tennessee State University; Fortner, Allison M [ORNL; Adams, Marshall [ORNL

    2012-01-01

    On December 22, 2008 a dike containing coal fly ash from the Tennessee Valley Authority Kingston Fossil Plant near Kingston Tennessee USA failed and resulted in the largest coal ash spill in U.S. history. Coal ash, the by-product of coal combustion, is known to contain multiple contaminants of concern, including arsenic and selenium. The purpose of this study was to investigate the bioaccumulation of arsenic and selenium and to identify possible differences in trophic dynamics in feral fish at various sites in the vicinity of the Kingston coal ash spill. Elevated levels of arsenic and selenium were observed in various tissues of largemouth bass, white crappie, bluegill and redear sunfish from sites associated with the Kingston coal ash spill. Highest concentrations of selenium were found in redear sunfish with liver concentrations as high as 24.83 mg/kg dry weight and ovary concentrations up to 10.40 mg/kg dry weight at coal ash-associated sites. To help explain the elevated selenium levels observed in redear sunfish, investigations into the gut pH and trophic dynamics of redear sunfish and bluegill were conducted which demonstrated a large difference in the gut physiology between these two species. Redear sunfish stomach and intestinal pH was found to be 1.1 and 0.16 pH units higher than in bluegill, respectively. In addition, fish from coal ash-associated sites showed enrichment of 15N & 13C compared to no ash sites, indicating differences in food web dynamics between sites. These results imply the incorporation of coal ash-associated compounds into local food webs and/or a shift in diet at ash sites compared to the no ash reference sites. Based on these results, further investigation into a broader food web at ash-associated sites is warranted.

  11. Washing of fly ash from combustion of municipal solid waste using water as leachant; Vattentvaett av flygaska fraan avfallsfoerbraenning

    Energy Technology Data Exchange (ETDEWEB)

    Steenari, Britt-Marie; Zhao, Dongmei

    2010-03-15

    Ashes from combustion of municipal solid waste contain a large amount of minerals, salts and other metal compounds that are more or less soluble in water. The metal salts are often enriched in the fly ash which leads to a classification of the ash as hazardous waste. This makes ash management complicated and costly. Many stabilisation methods for Municipal Solid Waste Incineration (MSWI) fly ash have been developed and most of them are based on a removal of chloride and sulfate in addition to a binding of metals in less soluble forms. The aim is to avoid the common situation that the ash does not comply to leaching limit values due to release of harmless salts. The aim of this project was to investigate if a simple washing with water can remove enough of the fly ash content of chloride and sulphate so that the ash can be landfilled in a simpler and less costly way than today. The project was focused on fly ashes from the MSWI units owned by Boraas Energi och Miljoe AB and Renova AB Goeteborg, i.e. a electro filter ash from grate fired boilers at Renova and a cyclone ash from a fluid bed boiler at Boraas. The results show that the main part of the chloride content of the ashes can be removed easily, but the washing with water is less effective in the removal of sulphate. A water-to-ash ratio of 1-2 l/kg removes about 100% of chloride but only 8-16% of the sulphate content. In many cases, the leachability of sulphate increases after the washing step. This is due to the rather complex sulphate chemistry with several possible reactions taking place in the ash-water system. For both the tested ashes the high level of chloride leaching is an important factor that prevents admittance on a landfill for hazardous waste without treatment.. The leaching of certain metals, such as Pb, is also high from both ashes but in the case of the Renova fly ash this is dealt with by treatment of the ash according to the Bamberg method. After a water washing with L/S 1-2 (L/kg dry ash

  12. Conditioning processes for incinerator ashes

    International Nuclear Information System (INIS)

    Jouan, A.; Ouvrier, N.; Teulon, F.

    1990-01-01

    Three conditioning processes for alpha-bearing solid waste incineration ashes were investigated and compared according to technical and economic criteria: isostatic pressing, cold-crucible direct-induction melting and cement-resin matrix embedding

  13. Characterisation of wood combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto

    The combustion of wood chips and wood pellets for the production of renewable energy in Denmark increased from 5.7 PJ to 16 PJ during the period 2000-2015, and further increases are expected to occur within the coming years. In 2012, about 22,300 tonnes of wood ashes were generated in Denmark....... Currently, these ashes are mainly landfilled, despite Danish legislation allowing their application onto forest and agricultural soils for fertilising and/or liming purposes. During this PhD work, 16 wood ash samples generated at ten different Danish combustion plants were collected and characterised...... for their composition and leaching properties. Despite the relatively large variations in the contents of nutrients and trace metals, the overall levels were comparable to typical ranges reported in the literature for other wood combustion ashes, as well as with regards to leaching. In general, the composition...

  14. Ash Stabilization Campaign Blend Plan

    International Nuclear Information System (INIS)

    Winstead, M.L.

    1995-01-01

    This Stabilization Blend Plan documents the material to be processed and the processing order for the FY95 Ash Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing ash. The source of the ash is from Rocky Flats and the 232-Z incinerator at the Plutonium Finishing Plant (PFP). The ash is currently being stored in Room 235B and Vault 174 in building 234-5Z. The sludge is to be thermally stabilized in a glovebox in room 230A of the 234-5Z building and material handling for the process will be done in room 230B of the same building. The campaign is scheduled for approximately 12--16 weeks. A total of roughly 4 kg of Pu will be processed

  15. DESIGN ANDFABRICATION OF DISPOSING DRY WASTEMATERIAL USING WASTE DESTROYING MACHINE

    OpenAIRE

    Dr. Nischal P. Mungle1, MahendraNimkar2, ArchanaN. Mungle3, Manjushree Mule4

    2018-01-01

    The dry waste material is type of waste material, waste materials like solid waste, liquid waste in atmosphere leads to unhygienic situation which affects human health and chances of disease increases. In our project by burning the dry waste material we are trying to control the waste materials in atmosphere. By using heating coil we are going to burn the dry waste material and in this way we are eliminating the dry waste materials, the ash which will going to be formed after burning the dry ...

  16. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  17. Briquetting fly ash from power plants for use as a charge in production of FeSiAl alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sosnowski, R.; Jastrzebski, R.; Podbiol, S.; Mendecki, K.

    1983-02-01

    The paper discusses waste product utilization of fly ash from black coal combustion for production of alloys consisting of iron, silicon and aluminium under laboratory conditions. Proportion of fly ash and coal reducing agent was 60% and 40%, grain size distribution of fly ash and coal ranged from 0 to 0.4 mm. Coal pitch and waste products from the cellulose industry were used as binders (resin soap, waste sulfite liquor etc.). Briquetting pressure was 400 kG/cm/sup 2/. Fly ash briquets were stabilized 168 h long and dried from 0.5 h to 1.0 h at 373 to 523 C. Effects of briquet composition, binders, briquetting pressure, stabilizing and drying on physical and mechanical properties of fly ash briquets are analyzed. The results of analyses are shown in 4 diagrams. Shatter test was used for determining briquet properties. The test shows that fly ash briquets with coal pitch, resin soap and waste sulfite liquor used as binders are characterized by compression strength not lower than 245 x 10/sup 4/ Pa and produce less than 5% fines in the shatter test. The tested fly ash briquets are a suitable charge for metallurgy. Effects of fly ash utilization on environmental protection are discussed. (8 refs.)

  18. Utilization of ash fractions from alternative biofuels used in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Nikolaisen, L.; Hinge, J.; Christensen, I. (Danish Technological Inst., Aarhus (Denmark)); Dahl, J. (Force Technology, Broendby (Denmark)); Arendt Jensen, P. (DTU-CHEC, Kgs. Lyngby (Denmark)); Soendergaard Birkmose, T. (Dansk Landbrugsraadgivning, Landscentret, Aarhus (Denmark)); Sander, B. (DONG Energy, Fredericia (Denmark)); Kristensen, O. (Kommunekemi A/S, Nyborg (Denmark))

    2008-07-15

    It is expected, that demand for the traditional biomass resources wood and straw will increase over the next years. In other projects a number of agro industrial waste products has been tested and characterized as fuels for power plants. The annual production in Denmark of these fuels is estimated at roughly 400.000 tons of Dry Matter per year, so the potential is substantial. The agro industrial biomass products include: Grain screening waste, pea shells, soy waste, cocoa waste, sugar beet waste, sunflower waste, shea waste, coffee waste, olive waste, rice shell waste, potato waste, pectin waste, carrageen waste, tobacco waste, rape seed waste and mash from breweries. In the PSO project 5075, 5 different types of fuel pellets was produced, which were rendered suitable for combustion in power plants. In this project, ash is produced from the above mentioned 5 mixtures together with another 2 mixtures produced especially for this project. From the 5 mixtures from PSO 5075, ash is produced at Danish Technological Institute's slag analyzer. These ash products are rendered comparable to ash from grate fired boilers at power plants. The ash/slag from the combustion in the slag analyzer was then grinded - thus resulting in a total of 5 ash products. At DTU CHEC's Entrained Flow Reactor, ash products from the 5+2 mixtures were produced. These ash products are rendered comparable to ash produced form suspension fired boilers at power plants. For each of the 7 mixtures, bottom-, cyclone and filter ash was taken out separately resulting in a total of 21 ash samples. The produced ashes have been evaluated for their properties as directly applied fertilizer. Furthermore, scenarios have been set up to assess the feasibility in producing artificial fertilizer from the ash products, based on known processes. In the main components the content of Na, S, Cl and K is significantly higher in filter ashes, whereas the content of Mg, Al, Si and Ca is significantly lower. The

  19. Pengaruh Kombinasi Fly Ash dan Bottom Ash sebagai Bahan Substitusi pada Campuran Beton terhadap Sifat Mekanis

    OpenAIRE

    Yahya, Tengku Tantoni; Kurniawandy, Alex; Djauhari, Zulfikar

    2017-01-01

    Fly ash and bottom ash were waste that generated from the power plant burning coal process. Fly ash and bottom ash has the potential to be developed as a basic ingredient in concrete composites. This research aimed to obtain the properties of fresh concrete and hard concrete of the combined effect of fly ash and bottom ash as a substitute ingredient in composite concrete. This research has examined the influence of a combination of waste fly ash and bottom ash to the compressive strength of a...

  20. Self compacting concrete incorporating high-volumes of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Bouzoubaa, N. [Natural Resources Canada, Ottawa, ON (Canada). International Centre for Sustainable Development of Cement and Concrete; Lachemi, M. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Civil Engineering

    2004-07-01

    Self-compacting concrete (SCC) is now widely used in reinforced concrete structures. Fine materials such as fly ash ensure that the concrete has the necessary properties of high fluidity and cohesiveness. An experimental study was conducted in which 9 SCC mixtures and one control concrete were produced in order to evaluate SCC made with high-volumes of fly ash. The content of the cementitious materials remained constant at 400 kg/cubic metre, but the ratio of water to cementitious material ranged from 0.35 to 0.45. The viscosity and stability of the fresh concrete was determined for self-compacting mixtures of 40, 50 and 60 per cent Class F fly ash. The compressive strength and drying shrinkage were also determined for the hardened concretes. Results showed that the SCCs developed a 28-day compressive strength ranging from 26 to 48 MPa. It was concluded that high-volumes of Class F fly ash could offer the following advantages to an SCC: reduced construction time and labour cost; eliminate the need for vibration; reduce noise pollution; improve the filling capacity of highly congested structural members; and, ensure good structural performance. 19 refs., 8 tabs., 2 figs.

  1. Ashes from straw and wood-chip fired plants for agricultural usage. Pilot project

    International Nuclear Information System (INIS)

    Morsing, M.; Westborg, S.

    1994-08-01

    The content of nutrients and heavy metals in ashes from the combustion of straw and wood chips at district heating plants is studied, on the basis of results of analyses from Danish municipalities, to determine whether such ashes are suitable for use as fertilizers. Results of the analysis of ashes from 9 wood-chip fired and 26 straw-fired plants are presented. They show significant variations in nutrient and heavy metal content which could be caused by combustion and operational conditions and/or testing methods. On condition that the phosphorous content of straw and wood-chip ashes amount to 1% of the dry matter, 50%-75% of the straw ashes and under 50% of wood chip ashes analyses are within the limit for cadmium stipulated in the Danish Ministry of the Environment's Executive Order no. 736 on the use of wastes for agricultural purposes. This is found to be unsatisfactory. It is suggested that a closer investigation should be undertaken in order to determine which amount of straw and wood-chip ashes can be accepted for use as fertilizers in consideration of the stipulated limits for cadmium content of wastes to be used for agricultural purposes. In addition the technological and economic potentials of dosing of these ashes for this use should be investigated. Fly ash and slag were also included in the analysis results studied and it was found that the cadmium content of slag did not prevent its use as fertilizer, but that the distribution of cadmium in slag, in fly ash and in slam from flue gas cleaning systems related to the combustion of wood chips should be further investigated. (AB)

  2. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  3. Characterization of ashes from biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, F.J.; Hansen, L.A. [Technical Univ. of Denmark. Dept. of Chemical Engineering (Denmark); Soerensen, H.S. [Geological Survey of Denmark and Greenland (Denmark); Hjuler, K. [dk-TEKNIK. Energy and Environment (Denmark)

    1998-02-01

    One motivation for initiating the present project was that the international standard method of estimating the deposit propensity of solid fuels, of which a number of variants exist (e.g. ISO, ASTM, SD, DIN), has shown to be unsuitable for biomass ashes. This goal was addressed by the development of two new methods for the detection of ash fusibility behaviour based on Simultaneous Thermal Analysis (STA) and High Temperature Light Microscopy (HTLM), respectively. The methods were developed specifically for ashes from biofuels, but are suitable for coal ashes as well. They have been tested using simple salt mixtures, geological standards and samples from straw CHP and coal-straw PF combustion plants. All samples were run in a nitrogen atmosphere at a heating rate of 10 deg. C/min. In comparison with the standard method, the new methods are objective and have superior repeatability and sensitivity. Furthermore, the two methods enable the melting behavior to be characterized by a continuous measurement of melt fraction versus temperature. Due to this two-dimensional resolution of the results, the STA and HTLM methods provide more information than the standard method. The study of bottom ash and fly ash as well as deposit samples from straw test firings at the Haslev and Slagelse Combined Heat and Power plants resulted in a better understanding of mineral behaviour during straw grate firing. In these tests a number of straws were fired which had been carefully selected for having different qualities with respect to sort and potassium and chlorine contents. By studying bottom ashes from Slagelse it was found that the melting behaviour correlated with the deposition rate on a probe situated at the outlet part of the combustion zone. (EG)

  4. Faecal-wood biomass co-combustion and ash composition analysis.

    Science.gov (United States)

    Somorin, Tosin Onabanjo; Kolios, Athanasios J; Parker, Alison; McAdam, Ewan; Williams, Leon; Tyrrel, Sean

    2017-09-01

    Fuel blending is a widely used approach in biomass combustion, particularly for feedstocks with low calorific value and high moisture content. In on-site sanitation technologies, fuel blending is proposed as a pre-treatment requirement to reduce moisture levels and improve the physiochemical properties of raw faeces prior to drying. This study investigates the co-combustion performance of wood dust: raw human faeces blends at varying air-to-fuel ratios in a bench-scale combustor test rig. It concludes with ash composition analyses and discusses their potential application and related problems. The study shows that a 50:50 wood dust (WD): raw human faeces (FC) can reduce moisture levels in raw human faeces by ∼40% prior to drying. The minimum acceptable blend for treating moist faeces without prior drying at a combustion air flow rate of 14-18 L/min is 30:70 WD: FC. For self-sustained ignition and flame propagation, the minimum combustion temperature required for conversion of the fuel to ash is ∼400 °C. The most abundant elements in faecal ash are potassium and calcium, while elements such as nickel, aluminium and iron are in trace quantities. This suggests the potential use of faecal ash as a soil conditioner, but increases the tendency for fly ash formation and sintering problems.

  5. 14C age of the ash found in the peat bed of upland dog, Nakagawa-Gun, Hokkaido

    International Nuclear Information System (INIS)

    Igarashi, Yaeko; Kondo, Tsutomu; Fujiwara, Koichiro.

    1983-01-01

    The determination of the 14 C age of volcanic ash forming thin layer, which was found in a peat bed, was carried out. The samples were collected from the peat bed which distributes on the flat top of upland about 450m above sea level. The moor spread in the experimental plantation of the agricultural department of Hokkaido University. The thin layer of volcanic ash was found 20 cm deep in the peat bed and with about 1-3 cm thickness. The determination of 14 C age was made on the peat directly beneath the volcanic ash layer, along with the mineralogical studies. The obtained 14 C age was 480 480 +- 100 Y.B.P. (A.D. 1470), and this is presumed to be the age of eruption of the volcanic ash. The color of the ash was greenish yellow or orange in wet state, and grayish white in dry state. The volcanic ash was fine grained pumiceous, and round or nearly round grains predominate. By macroscopic observation, the grains were found to be composed of fibrous volcanic glass. The volcanic ash was well sorted, and the central grain size was 0.11 mm. Heavy liquid method was applied for the determination of heavy minerals. The weight percentage of heavy minerals was 1.59, and the characteristic of this ash was the entire absence of amphibole. Further investigation is necessary for clarifying the distribution of volcanic ash and the source of eruption. (Ishimitsu, A.)

  6. Utilization of wood ash as seedling media of Cocoa (Theobroma cacao

    Directory of Open Access Journals (Sweden)

    Fitria Nugraheni Sukmawati

    2016-12-01

    Full Text Available An effort to increase productivity is provision of inorganic fertilizers. Inorganic fertilizer application in longtem as found to attenuate the availability of micronutrients and to decrease soil fertility. One possibility to replace inorganic fertilizer is the use of ash derived from plants, such as wood ash. The purpose of this study was to determine the effect of wood ash on soil K availability and to optimize the dose of wood ash which can give good influence on the growth of cocoa seedlings. The experiment was conducted at the experimental station Polytechnic LPP in Wedomartani, Sleman, Yogyakarta. The design used is non factorial randomized block design with 5 treatments, which is the ratio of ash and soil 0: 1 (A1 / Control; 0.25: 1 (A2; 0.5: 1 (A3; 0.75: 1 (A4; and 1: 1 (A5. Observations of treatment effects were made on the seedling height, number of leaves, stem diameter, wet weight and dry weight. Soil analysis was conducted to determine the content of macro elements, micro elements, and pH media. The results showed that ash increases the pH of the media to alkaline range and increase the availability of P and K soil to toxic range. Giving ash reduced the availability of N and caused chlorosis on cocoa seedlings.

  7. A study of fine aggregate replacement with fly ash an environmental friendly and economical solution.

    Science.gov (United States)

    Pofale, A D; Deo, S V

    2010-10-01

    The use of fly ash as a replacement of sand has a great potential to benefit our society in terms of reducing demand of natural sand, reducing environmental problems, conserving energy and reducing landfill area requirement. This paper presents an approach to increase the utilization of fly ash and conserve scarcely available natural sand for sustainable development. The experimental investigation by the inclusion of fly ash as a partial replacement of sand as compared to control cement mortar mixes indicated 50% to 100% increase in the compressive strength of mortar at 91 days. Replacement of 50% sand with fly ash can save about 0.4 m3 sand. Comparison of cost per N/mm2 compressive strength has shown about 40% to 60% saving in cost. Based on the experimental results, correlations are developed for finding out the compressive strength and cost at 28 and 91 days. Sand was replaced with 10% to 50% of fly ash by weight and 0.5, 0.55, 0.6 and 0.65 W/C ratios were used. Flow test performed for mortar revealed that as the percentage replacement of sand with the fly ash increased the flow of the mortar decreased. It was also observed that wet and dry densities were more than the control mortar for 10% & 20% replacement of sand with fly ash but for higher replacement percentage density reduced marginally.

  8. The Effect of Fly Ash on the Corrosion Behaviour of Galvanised Steel Rebarsin Concrete

    Science.gov (United States)

    Tittarelli, Francesca; Mobili, Alessandra; Bellezze, Tiziano

    2017-08-01

    The effect of fly ash on the corrosion behaviour of galvanised steel rebars in cracked concrete specimens exposed to wet-dry cycles in a chloride solution has been investigated. The obtained results show that the use of fly ash, replacing either cement or aggregate, always improves the corrosion behaviour of galvanised steel reinforcements. In particular, the addition of fly ash, even in the presence of concrete cracks, decreases the corrosion rate monitored in very porous concretes, as those with w/c = 0.80, to values comparable with those obtained in good quality concretes, as those with w/c = 0.45. Therefore, fly ash cancels the negative effect, at least from the corrosion point of view, of a great porosity of the cement matrix.

  9. Effect of moisture on the accuracy of coke-ash determination by X-ray backscattering

    International Nuclear Information System (INIS)

    Pandey, H.D.; Prasad, M.S.

    1984-01-01

    Effect of moisture on the rapid non-destructive estimation of ash content in coal specimens using the X-ray backscattering technique has been studied extensively by various workers. In the present work, an attempt has been made to estimate its influence when the technique is extended to coke-ash determinations. From the study of the variation of backscattered intensity with change in the moisture content of a coke specimen, it is observed that the ash content varies significantly at moisture levels higher than 5%. The variation, however, remains within allowable limits if the moisture level is kept below 5%. This observation is confirmed by the actual measurement of ash percentages in thirteen coke specimens containing three different states of moisture levels viz. (i) in the dry state, (ii) with 5% moisture and (iii) with 10% moisture. (author)

  10. Ash in fire affected ecosystems

    Science.gov (United States)

    Pereira, Paulo; Jordan, Antonio; Cerda, Artemi; Martin, Deborah

    2015-04-01

    Ash in fire affected ecosystems Ash lefts an important footprint in the ecosystems and has a key role in the immediate period after the fire (Bodi et al., 2014; Pereira et al., 2015). It is an important source of nutrients for plant recover (Pereira et al., 2014a), protects soil from erosion and controls soil hydrological process as runoff, infiltration and water repellency (Cerda and Doerr, 2008; Bodi et al., 2012, Pereira et al., 2014b). Despite the recognition of ash impact and contribution to ecosystems recuperation, it is assumed that we still have little knowledge about the implications of ash in fire affected areas. Regarding this situation we wanted to improve our knowledge in this field and understand the state of the research about fire ash around world. The special issue about "The role of ash in fire affected ecosystems" currently in publication in CATENA born from the necessity of joint efforts, identify research gaps, and discuss future cooperation in this interdisciplinary field. This is the first special issue about fire ash in the international literature. In total it will be published 10 papers focused in different aspects of the impacts of ash in fire affected ecosystems from several parts of the world: • Fire reconstruction using charcoal particles (Burjachs and Espositio, in press) • Ash slurries impact on rheological properties of Runoff (Burns and Gabet, in press) • Methods to analyse ash conductivity and sorbtivity in the laboratory and in the field (Balfour et al., in press) • Termogravimetric and hydrological properties of ash (Dlapa et al. in press) • Effects of ash cover in water infiltration (Leon et al., in press) • Impact of ash in volcanic soils (Dorta Almenar et al., in press; Escuday et al., in press) • Ash PAH and Chemical extracts (Silva et al., in press) • Microbiology (Barreiro et al., in press; Lombao et al., in press) We believe that this special issue will contribute importantly to the better understanding of

  11. Dry storage

    International Nuclear Information System (INIS)

    Arnott, Don.

    1985-01-01

    The environmental movement has consistently argued against disposal of nuclear waste. Reasons include its irretrievability in the event of leakage, the implication that reprocessing will continue and the legitimacy attached to an expanding nuclear programme. But there is an alternative. The author here sets out the background and a possible future direction of a campaign based on a call for dry storage. (author)

  12. Development of novel ash hybrids to introgress resistance to emerald ash borer into north American ash species

    Science.gov (United States)

    Jennifer L. Koch; David W. Carey; Mary E. Mason

    2008-01-01

    Currently, there is no evidence that any of the native North American ash species have any resistance to the emerald ash borer (EAB). This means that the entire ash resource of the eastern United States and Canada is at risk of loss due to EAB. In contrast, outbreaks of EAB in Asian ash species are rare and appear to be isolated responses to stress (Bauer et al. 2005,...

  13. Growth and elemental content of two tree species growing on abandoned coal fly ash basins

    International Nuclear Information System (INIS)

    Carlson, C.L.; Adriano, D.C.

    1991-01-01

    Differences in aboveground tissue concentrations of trace elements were assessed for sweetgum (Liquidambar styraciflua L.) and sycamore (Plantanus occidentalis L.) growing on two abandoned coal fly ash basins and a control soil. The wet basin (pH = 5.58) had originally received precipitator ash in an ash-water slurry, while the dry basin (pH = 8.26) had received both precipitator and bottom ash in dry form. In general, trees from the wet basin exhibited elevated trace element concentrations in comparison to the controls, while the dry basin trees exhibited reduced concentrations. On eof the most striking differenced in elemental concentrations among the ash basin and control trees was observed for Mn, with the control trees exhibiting concentrations orders of magnitude greater than the ash basin trees. Differences in foliar trace element concentrations among the sites can generally be explained by differences in substrate trace element concentrations and/or substrate pH. While trees from the wet ash basin generally had the highest trace element concentrations, these trees also attained the greatest height and diameter growth, suggesting that the elevated trace element concentrations in the wet basin substrate are not limiting the establishment of these two species. The greater height and diameter growth of the wet basin trees is presumably a result of the greater water-holding capacity of the substrate on this site. Differences in growth and tissue concentrations between sweetgum and sycamore highlight the importance of using more than one species when assessing metal toxicity or deficiency on a given substrate

  14. Characterization of Fly and Bottom Ashes Mixtures Treated using Sodium Lauryl Sulphate and Polyvinyl Alcohol

    Directory of Open Access Journals (Sweden)

    Robert C.G.

    2018-01-01

    Full Text Available Malaysia promotes coal as an option for solid fuel in electric power generation. Demanding of electricity needs, therefore, has led to increase the coal consumption and thus producing more coal waste products. The disposal of coal waste ashes has been a main concern to power generation station due to the need of disposal sites and operational costs. This study investigates the composition of fly ash (FA and bottom ash (BA mixtures with difference component percentage treated with sodium lauryl sulphate (SLS and polyvinyl alcohol (PVA at 1.5 and 2.5 wt% solutions and examined in terms of specific gravity, pH, maximum dry density properties, and its surface morphology. Although the chemical composition of the SLS and PVA treated fly and bottom ashes studied in this current work is not altered extensively, significant changes could be observed in its physicochemical properties. Chemically treated fly and bottom ashes mixtures with SLS and PVA at 1.5 wt% solution exhibited specific gravity of 1.97 to 2.92 and high pH values within range of 9.28 to 10.52. The mixture of BA:FA=0:1 ratio depicting high maximum dry density of 1.35 to 1.56 g/cm3 in both SLS and PVA solutions at 1.5 and 2.5 wt%. Scanning electron microscopy image shows distinct surface morphologies of SLS-treated fly and bottom ashes mixture that the particles are packed closely, strongly bonded similar to popcorn shape due to the effect of active silanol groups acted on coal ashes surface with the presence of Al-O/Si-O/other oxides. These findings suggest that higher level of chemical interaction between the fly and bottom ashes particles, significantly enhances pozzolanic reactions such as shear strength, plasticity, cementing properties, and thus other engineering properties.

  15. Characterization of Fly and Bottom Ashes Mixtures Treated using Sodium Lauryl Sulphate and Polyvinyl Alcohol

    Science.gov (United States)

    Robert, C. G.; Ayob, A.; Zaki, M. F. Muhammad; Razali, M. E.; Lew, E. V.; Hong, P. Y.

    2018-03-01

    Malaysia promotes coal as an option for solid fuel in electric power generation. Demanding of electricity needs, therefore, has led to increase the coal consumption and thus producing more coal waste products. The disposal of coal waste ashes has been a main concern to power generation station due to the need of disposal sites and operational costs. This study investigates the composition of fly ash (FA) and bottom ash (BA) mixtures with difference component percentage treated with sodium lauryl sulphate (SLS) and polyvinyl alcohol (PVA) at 1.5 and 2.5 wt% solutions and examined in terms of specific gravity, pH, maximum dry density properties, and its surface morphology. Although the chemical composition of the SLS and PVA treated fly and bottom ashes studied in this current work is not altered extensively, significant changes could be observed in its physicochemical properties. Chemically treated fly and bottom ashes mixtures with SLS and PVA at 1.5 wt% solution exhibited specific gravity of 1.97 to 2.92 and high pH values within range of 9.28 to 10.52. The mixture of BA:FA=0:1 ratio depicting high maximum dry density of 1.35 to 1.56 g/cm3 in both SLS and PVA solutions at 1.5 and 2.5 wt%. Scanning electron microscopy image shows distinct surface morphologies of SLS-treated fly and bottom ashes mixture that the particles are packed closely, strongly bonded similar to popcorn shape due to the effect of active silanol groups acted on coal ashes surface with the presence of Al-O/Si-O/other oxides. These findings suggest that higher level of chemical interaction between the fly and bottom ashes particles, significantly enhances pozzolanic reactions such as shear strength, plasticity, cementing properties, and thus other engineering properties.

  16. New-Generation Aluminum Composite with Bottom Ash Industrial Waste

    Science.gov (United States)

    Mandal, A. K.; Sinha, O. P.

    2018-06-01

    Industrial waste bottom ash (BA) from a pulverized coal combustion boiler containing hard wear-resistant particles was utilized in this study to form an aluminum composite through a liquid metallurgy route. Composites comprising 5 wt.% and 10 wt.% bottom ash were characterized for their physiochemical, microstructural, mechanical, as well as tribological properties, along with pure aluminum. Scanning electron microscopy (SEM) microstructure revealed uniform distribution of BA particles throughout the matrix of the composite, whereas x-ray diffraction (XRD) analysis confirmed presence of aluminosilicate phase. Addition of 10 wt.% BA improved the Brinell hardness number (BHN) from 13 to 19 and ultimate tensile strength (UTS) from 71 MPa to 87 MPa, whereas ductility was adversely reduced after 5% BA addition. Incorporation of BA particles resulted in reduced dry sliding wear rates examined up to 80 N load compared with aluminum. Hence, such composites having lower cost could be applied as significantly hard, wear-resistant materials in applications in the automotive industry.

  17. New-Generation Aluminum Composite with Bottom Ash Industrial Waste

    Science.gov (United States)

    Mandal, A. K.; Sinha, O. P.

    2018-02-01

    Industrial waste bottom ash (BA) from a pulverized coal combustion boiler containing hard wear-resistant particles was utilized in this study to form an aluminum composite through a liquid metallurgy route. Composites comprising 5 wt.% and 10 wt.% bottom ash were characterized for their physiochemical, microstructural, mechanical, as well as tribological properties, along with pure aluminum. Scanning electron microscopy (SEM) microstructure revealed uniform distribution of BA particles throughout the matrix of the composite, whereas x-ray diffraction (XRD) analysis confirmed presence of aluminosilicate phase. Addition of 10 wt.% BA improved the Brinell hardness number (BHN) from 13 to 19 and ultimate tensile strength (UTS) from 71 MPa to 87 MPa, whereas ductility was adversely reduced after 5% BA addition. Incorporation of BA particles resulted in reduced dry sliding wear rates examined up to 80 N load compared with aluminum. Hence, such composites having lower cost could be applied as significantly hard, wear-resistant materials in applications in the automotive industry.

  18. Solidification of radioactive incinerator ash

    International Nuclear Information System (INIS)

    Schuler, T.F.; Charlesworth, D.L.

    1986-01-01

    The Ashcrete process will solidify ash generated by the Beta Gamma Incinerator (BGI) at the Savannah River Plant (SRP). The system remotely handles, adds material to, and tumbles drums of ash to produce ashcrete, a stabilized wasteform. Full-scale testing of the Ashcrete unit began at Savannah River Laboratory (SRL) in January 1984, using nonradioactive ash. Tests determined product homogeneity, temperature distribution, compressive strength, and final product formulation. Product formulations that yielded good mix homogeneity and final product compressive strength were developed. Drum pressurization and temperature rise (resulting from the cement's heat of hydration) were also studied to verify safe storage and handling characteristics. In addition to these tests, an expert system was developed to assist process troubleshooting

  19. Emerald ash borer biocontrol in ash saplings: the potential for early stage recovery of North American ash

    Science.gov (United States)

    In many parts of North America, ash stands have been reduced by the emerald ash borer (Agrilus planipennis) invasion to a few surviving mature trees and young basal sprouts, saplings, and seedlings. Without a seed bank, ash tree recovery will require survival and maturation of these younger cohorts...

  20. evaluation of atomic absorption spectrophotometry (ashing, non ...

    African Journals Online (AJOL)

    cistvr

    1Department of Agricultural and Food Science and 2Department of ... used techniques, namely atomic absorption spectrophotometry (AAS-Ashing and ..... fact that more preparation steps were involved in the Ashing procedure and thus.

  1. Ash content of lignites - radiometric analysis

    International Nuclear Information System (INIS)

    Leonhardt, J.; Thuemmel, H.W.

    1986-01-01

    The quality of lignites is governed by the ash content varying in dependence upon the geologic conditions. Setup and function of the radiometric devices being used for ash content analysis in the GDR are briefly described

  2. The influence of coal bottom ash and tincal (boron mineral) additions on the physical and microstructures of ceramic bodies

    Energy Technology Data Exchange (ETDEWEB)

    Bayca, S.U.; Batar, T.; Sayin, E.; Solak, O.; Kahraman, B. [Celal Bayar University, Manisa (Turkey). Soma Vocational School

    2008-07-01

    In this paper, the influence of coal bottom ash and tincal additions on the physical properties and microstructures of the standard wall tile body composition was investigated. Water absorption, fang strength, dry and fired shrinkage tests of the incorporated ceramic bodies and reference body were done. Microstructures of sintered tiles were analyzed using a scanning electron microscope (SEM). The results show that tincal additions to the ceramic body improved the physical properties of the tiles. As a result, tincal can be used as a flux material in the ceramic bodies due to its favorable effects on the water absorption and fired strength. The results revealed that bottom ash can be used in the ceramic tile body composition. When bottom ash was used in the ceramic industry, environmental hazards of bottom ash are inhibited. Furthermore, bottom ash is transformed to an economic product.

  3. ETVS - a process for decentral processing of liquid, pasty and solid organic residues into electrical energy and ash, optionally with hydrosoft high-pressure dewatering, fluidized-bed drying, fluidized-bed gasification and heat-and-power cogeneration using product gas; ETVS - Ein Verfahren zur dezentralen Verwertung von fluessigen, pastoesen und festen biologischen Reststoffen in elektrische Energie und Asche, bedarfsweise mit Hydrosoft-Hochdruckentwaesserung, Wirbelschicht-Trockner, Wirbelschicht-Vergaser und Produktgas-Kraft-Waerme-Kopplung

    Energy Technology Data Exchange (ETDEWEB)

    Eder, C.; Eder, G. [Christian Eder Technology, Neunkirchen (Germany); Wied, E. [Bisanz GmbH, Saarbruecken (Germany)

    1999-07-01

    By means of the ETVS process, predominantly liquid organic residues can be converted into electrical energy and mineral ash decentrally, i.e. where they accrue. The process is exemplified with reference to sewage sludge. Sludge containing at least about 4 % dry residue is dewatered to the highest dry substance content possible. The obtained filter cakes are indirectly dried in a fluidized-bed drier using internal process waste heat. Then the organic sewage sludge constituents are gasified in an atmospheric fluidized bed system. The cleaned product gas is used to generate power in a cogeneration power plant, meeting the sewage treatment plant's in-house power demand. The ETVS process is self-sufficient in terms of thermal energy requirement from an initial dry substance content of the filter cake > 40 %. Incineration is a means of disposing of sewage sludge in accordance with the boundary conditions for sewage sludge disposal from 2005, laid down in the technical code on municipal waste. Combining the ETVS process with modern biological treatment stages makes for a substantial cut in the construction and operating cost of sewage treatment plants. (orig.) [German] Mit dem ETVS-Verfahren koennen ueberwiegend fluessige biologische Reststoffe dezentral, d.h. an der Anfallstelle in eigennutzbare elektrische Energie und mineralische Asche umgewandelt werden. Das Verfahren wird am Klaerschlamm beispielhaft dargestellt. Der Klaerschlamm wird ab einem Trockensubstanzgehalt von ca. 4%TR auf moeglichst hohe Trockensubstanzgehalte entwaessert und die dabei erzeugten Filterkuchen mit internen Prozessabwaermen in einem Wirbelschichttrockner indirekt getrocknet. Die organischen Bestandteile des Klaerschlammes werden anschliessend in einer ebenfalls atmosphaerischen Wirbelschichtanlage vergast. Der mit dem gereinigten Produktgas in einer KWK-Anlage erzeugte Strom wird zur Deckung des Eigenbedarfs der Klaeranlage verwandt. Durch die Veraschung liefert das ab einem

  4. Exploring the molecular and biochemical basis of ash resistance to emerald ash borer

    Science.gov (United States)

    Justin G.A. Whitehill; Daniel A. Herms; Pierluigi. Bonello

    2010-01-01

    Larvae of the emerald ash borer (EAB) (Agrilus planipennis) feed on phloem of ash (Fraxinus spp.) trees. It is hypothesized that the resistance of Asian species of ash (e.g., Manchurian ash, F. mandshurica) to EAB is due to endogenous defenses present in phloem tissues in the form of defensive proteins and/or...

  5. Temporal evolution of wildfire ash and its implications for water pollution

    Science.gov (United States)

    Santin, Cristina; Doerr, Stefan H.; Otero, Xose L.; Chafer, Chris J.

    2015-04-01

    Ash, the burnt residue generated from combustion of vegetation, litter and surface soil, covers the ground after every wildfire. The effects of wildfire ash on the post-fire landscape are many and very diverse. It is a source of nutrients and can, therefore, help the recovery of vegetation after fire. Furthermore, in its initial state, the ash layer on the ground can protect the bare soil from rain splash erosion and can act as an adsorbent layer, preventing or delaying post-fire water erosion by runoff. However, when the adsorbent capability of the ash layer is exceeded, this highly erodible material can be transported into the hydrological network and be a major contributor to water contamination. Most previous studies on post-fire erosion and water contamination have focused on soil erosion and associated sediment transfer and overlooked the ash component or, when considered, ash has been included as an unidentified part of the eroded sediment. One of the reasons for overlooking this key post-fire component is the difficulty of ash sampling before it is lost by wind or water erosion or altered by aging on-site. Here we compare the water contamination potential of ash obtained from two fires in the dry eucalyptus forest environment of the Sydney tablelands, Australia: i) 'aged ash' produced during the severe Balmoral wildfire and sampled two months after the event (Jan. 2014) and ii) 'fresh ash' sampled immediately after a high-intensity experimental fire in the same region (Sept. 2014). At the time of sampling, neither of the ash types had been affected by water erosion, however, the aged ash had been subjected to rainfall events and, potentially, to wind erosion during the two months of exposure. Vegetation type, fuel loads and fire severity, determined using remote sensing and on-site observations, were comparable between both areas sampled. Ash physicochemical properties differed, with 'fresh ash' having higher pH and EC values and higher concentration of

  6. Colour, compressive strength and workability of mortars with an iron rich sewage sludge ash

    DEFF Research Database (Denmark)

    Kappel, Annemette; Ottosen, Lisbeth M.; Kirkelund, Gunvor Marie

    2017-01-01

    This paper reports a study of the colour, compressive strength and workability of mortar when cement is partly replaced by sewage sludge ash (SSA). In the study, an iron rich SSA was dry milled into six different fractions. The results showed that the colour, compressive strength and workability...

  7. Effect of Cement–Locust Bean Waste Ash Blend on the Gradation ...

    African Journals Online (AJOL)

    OPC) and up to 8% locust bean waste ash (LBWA) by dry weight of soil to investigate its effect on the gradation and plasticity characteristics of the modified soil. Test results generally show that the gradation and plasticity characteristics of the ...

  8. Transcriptomic signatures of ash (Fraxinus spp. phloem.

    Directory of Open Access Journals (Sweden)

    Xiaodong Bai

    2011-01-01

    Full Text Available Ash (Fraxinus spp. is a dominant tree species throughout urban and forested landscapes of North America (NA. The rapid invasion of NA by emerald ash borer (Agrilus planipennis, a wood-boring beetle endemic to Eastern Asia, has resulted in the death of millions of ash trees and threatens billions more. Larvae feed primarily on phloem tissue, which girdles and kills the tree. While NA ash species including black (F. nigra, green (F. pennsylvannica and white (F. americana are highly susceptible, the Asian species Manchurian ash (F. mandshurica is resistant to A. planipennis perhaps due to their co-evolutionary history. Little is known about the molecular genetics of ash. Hence, we undertook a functional genomics approach to identify the repertoire of genes expressed in ash phloem.Using 454 pyrosequencing we obtained 58,673 high quality ash sequences from pooled phloem samples of green, white, black, blue and Manchurian ash. Intriguingly, 45% of the deduced proteins were not significantly similar to any sequences in the GenBank non-redundant database. KEGG analysis of the ash sequences revealed a high occurrence of defense related genes. Expression analysis of early regulators potentially involved in plant defense (i.e. transcription factors, calcium dependent protein kinases and a lipoxygenase 3 revealed higher mRNA levels in resistant ash compared to susceptible ash species. Lastly, we predicted a total of 1,272 single nucleotide polymorphisms and 980 microsatellite loci, among which seven microsatellite loci showed polymorphism between different ash species.The current transcriptomic data provide an invaluable resource for understanding the genetic make-up of ash phloem, the target tissue of A. planipennis. These data along with future functional studies could lead to the identification/characterization of defense genes involved in resistance of ash to A. planipennis, and in future ash breeding programs for marker development.

  9. Gasification of high ash, high ash fusion temperature bituminous coals

    Science.gov (United States)

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

    2015-11-13

    This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

  10. Ash characteristics and plant nutrients in some aquatic biomasses

    Science.gov (United States)

    Masto, Reginald; Pandit, Ankita; George, Joshy; Mukhopadhyay, Sangeeta; Selvi, Vetrivel; Ram, Lal

    2016-04-01

    Aquatic biomasses are explored as potential fuel source for direct combustion because of their faster growth and no land requirement. The energy density and the ash characteristics of the aquatic biomasses are to be evaluated for their suitability for energy extraction. In the study, four aquatic plant samples namely Eichornia crassipes, Hydrilla verticilleta, Lemna minor, Spirogyra spp were collected from a pond in Digwadih Campus of Central Institute of Mining and Fuel Research, Dhanbad. The biomasses were air dried, powdered and ashed at different temperatures. Volatile C was relatively lower in Spirogyra and Hydrilla (53 %) than Eichornia (62.6 %) or Lemna (59.7 %), whereas fixed C was higher for Eichornia and Lemna (about 10 %) and lower for Hydrilla (1 %). Ultimate analysis showed that the carbon content was in the order Eichornia > Lemna > Spirogyra > Hydrilla. The IR spectra of each raw biomass is compared to their respective ashes obtained at different temperatures (500-900°C). With increase in ashing temperature from 500-900°C there is gradual breakdown of the cellulosic structure hence, peaks around 2900-2800cm-1 caused by aliphatic C-H vibration tends to disappear slowly in ash. More number of peaks appears at lower wavenumbers in ashes of all the biomass samples indicating towards increased percentage of inorganic ion species. Considerable enrichment of SiO2 is validated with prominent peaks at 1100-900 cm-1 in all the ashes. Lemna and Spirogyra has a similar ash composition (Si > Al > Ca > K), whereas, Ca was higher in Hydrilla (Si > Ca > K > Al). Eichornia (Si > K > Ca > Al) has higher K and Ca than Al. SiO2 and Al2O3 were higher in Spirogyra, while SiO2 and CaO in Eichornia and Hydrilla. K first increased from 500-700/800⁰C, and then decreased from 800-900⁰C. Cl is lost slowly in ash from 500-700/800⁰C and then by a drastic reduction from 800-900⁰C. S is enhanced in ash at all temperatures although the change is quite small. Most of the Cl

  11. Impact of Collection Equipment on Ash Variability of Baled Corn Stover Biomass for Bioenergy

    Energy Technology Data Exchange (ETDEWEB)

    William Smith; Jeffery Einerson; Kevin Kenney; Ian J. Bonner

    2014-09-01

    Cost-effective conversion of agricultural residues for renewable energy hinges not only on the material’s quality but also the biorefinery’s ability to reliably measure quality specifications. The ash content of biomass is one such specification, influencing pretreatment and disposal costs for the conversion facility and the overall value of a delivered lot of biomass. The biomass harvest process represents a primary pathway for accumulation of soil-derived ash within baled material. In this work, the influence of five collection techniques on the total ash content and variability of ash content within baled corn stover in southwest Kansas is discussed. The equipment tested included a mower for cutting the corn stover stubble, a basket rake, wheel rake, or shred flail to gather the stover, and a mixed or uniform in-feed baler for final collection. The results showed mean ash content to range from 11.5 to 28.2 % depending on operational choice. Resulting impacts on feedstock costs for a biochemical conversion process range from $5.38 to $22.30 Mg-1 based on the loss of convertible dry matter and ash disposal costs. Collection techniques that minimized soil contact (shred flail or nonmowed stubble) were shown to prevent excessive ash contamination, whereas more aggressive techniques (mowing and use of a wheel rake) caused greater soil disturbance and entrainment within the final baled material. Material sampling and testing were shown to become more difficult as within-bale ash variability increased, creating uncertainty around feedstock quality and the associated costs of ash mitigation.

  12. Coal ash artificial reef demonstration

    International Nuclear Information System (INIS)

    Livingston, R.J.; Brendel, G.F.; Bruzek, D.A.

    1991-01-01

    This experimental project evaluated the use of coal ash to construct artificial reefs. An artificial reef consisting of approximately 33 tons of cement-stabilized coal ash blocks was constructed in approximately 20 feet of water in the Gulf of Mexico approximately 9.3 miles west of Cedar Key, Florida. The project objectives were: (1) demonstrate that a durable coal ash/cement block can be manufactured by commercial block-making machines for use in artificial reefs, and (2) evaluate the possibility that a physically stable and environmentally acceptable coal ash/cement block reef can be constructed as a means of expanding recreational and commercial fisheries. The reef was constructed in February 1988 and biological surveys were made at monthly intervals from May 1988 to April 1989. The project provided information regarding: Development of an optimum design mix, block production and reef construction, chemical composition of block leachate, biological colonization of the reef, potential concentration of metals in the food web associated with the reef, acute bioassays (96-hour LC 50 ). The Cedar Key reef was found to be a habitat that was associated with a relatively rich assemblage of plants and animals. The reef did not appear to be a major source of heavy metals to species at various levels of biological organization. GAI Consultants, Inc (GAI) of Monroeville, Pennsylvania was the prime consultant for the project. The biological monitoring surveys and evaluations were performed by Environmental Planning and Analysis, Inc. of Tallahassee, Florida. The chemical analyses of biological organisms and bioassay elutriates were performed by Savannah Laboratories of Tallahassee, Florida. Florida Power Corporation of St. Petersburg, Florida sponsored the project and supplied ash from their Crystal River Energy Complex

  13. Formation and utilization of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Vargyai, J

    1974-01-01

    General problems of slag and fly ash formation and utilization are discussed. The ever-increasing energy demand, and the comeback of coal as an energy carrier in power plants call for efficient solutions to the problem of slag and fly ash. Slag and fly ash are used for concrete in which they partly replace cement. Other possible uses are the amelioration of acid soils, fireclay manufacture, road construction, and tiles. It is possible to recover metals, such as vanadium, iron, aluminum, and radioactive materials from certain types of fly ash and slag. The utilization of fly ash is essential also with respect to the abatement of entrainment from dumps.

  14. Engineering Behavior and Characteristics of Wood Ash and Sugarcane Bagasse Ash

    Directory of Open Access Journals (Sweden)

    Francisco Grau

    2015-10-01

    Full Text Available Biomasses are organic materials that are derived from any living or recently-living structure. Plenty of biomasses are produced nationwide. Biomasses are mostly combusted and usually discarded or disposed of without treatment as biomass ashes, which include wood and sugarcane bagasse ashes. Thus, recycling or treatment of biomass ashes leads to utilizing the natural materials as an economical and environmental alternative. This study is intended to provide an environmental solution for uncontrolled disposal of biomass ashes by way of recycling the biomass ash and replacing the soils in geotechnical engineering projects. Therefore, in this study, characteristic tests of wood and sugarcane bagasse ashes that are considered the most common biomass ashes are conducted. The test of chemical compositions of biomass ashes is conducted using energy dispersive X-ray spectroscopy (EDS, and Scanning Electron Microscope (SEM, and heavy metal analysis is also conducted. Engineering behaviors including hydraulic conductivity, constrained modulus and shear modulus are examined. Also, coal fly ash Class C is used in this study for comparison with biomass ashes, and Ottawa 20/30 sands containing biomass ashes are examined to identify the soil replacement effect of biomass ashes. The results show that the particle sizes of biomass ashes are halfway between coal fly ash Class C and Ottawa 20/30 sand, and biomass ashes consist of a heterogeneous mixture of different particle sizes and shapes. Also, all heavy metal concentrations were found to be below the US Environmental Protection Agency (EPA maximum limit. Hydraulic conductivity values of Ottawa 20/30 sand decrease significantly when replacing them with only 1%–2% of biomass ashes. While both the constrained modulus and shear modulus of biomass ashes are lower than Ottawa 20/30 sand, those of mixtures containing up to 10% biomass ashes are little affected by replacing the soils with biomass ashes.

  15. Identifying glass compositions in fly ash

    Directory of Open Access Journals (Sweden)

    Katherine eAughenbaugh

    2016-01-01

    Full Text Available In this study, four Class F fly ashes were studied with a scanning electron microscope; the glassy phases were identified and their compositions quantified using point compositional analysis with k-means clustering and multispectral image analysis. The results showed that while the bulk oxide contents of the fly ashes were different, the four fly ashes had somewhat similar glassy phase compositions. Aluminosilicate glasses (AS, calcium aluminosilicate glasses (CAS, a mixed glass, and, in one case, a high iron glass were identified in the fly ashes. Quartz and iron crystalline phases were identified in each fly ash as well. The compositions of the three main glasses identified, AS, CAS, and mixed glass, were relatively similar in each ash. The amounts of each glass were varied by fly ash, with the highest calcium fly ash containing the most of calcium-containing glass. Some of the glasses were identified as intermixed in individual particles, particularly the calcium-containing glasses. Finally, the smallest particles in the fly ashes, with the most surface area available to react in alkaline solution, such as when mixed with portland cement or in alkali-activated fly ash, were not different in composition than the large particles, with each of the glasses represented. The method used in the study may be applied to a fly ash of interest for use as a cementing material in order to understand its potential for reactivity.

  16. Effects of Wood Ash on Soil Fungi

    DEFF Research Database (Denmark)

    Cruz Paredes, Carla

    ), copper (Cu) and nickel (Ni), is a major environmental concern. This work is part of the project ASHBACK (www.ashback.dk) which addresses the potentials and possible problems in re-distributing wood ash to the forest. The aim of this thesis was to determine the effects of biomass ash application...... in a Norway spruce forest where different amounts of wood ash were spread on the soil to study the effects on ectomycorrhizal (ECM) fungi, bioaccumulation of metals in sporocarps, and microbial communities. Laboratory microcosm experiments were run in parallel to the field studies, to compare the effects...... of wood ash with factorial additions of lime and Cd to disentangle the pH and Cd effects of wood ash amendments using community trait distributions. Barley yield, P content, and Cd content were not affected by biomass ashes. Some arbuscular mycorrhizal (AM) fungal species were reduced when biomass ashes...

  17. Thermo-mechanical properties and microfabric of fly ash-stabilized gold tailings.

    Science.gov (United States)

    Lee, Joon Kyu; Shang, Julie Q; Jeong, Sangseom

    2014-07-15

    This paper studies the changes in thermal conductivity, temperature, and unconfined compressive strength of gold tailings and fly ash mixtures during the curing period of 5 days. The microfabric of the cured mixtures was investigated with mercury intrusion porosimetry (MIP). The mixture samples were prepared at their maximum dry unit weight and optimum moisture content. Effect of adding fly ash to gold tailings (i.e., 0, 20, and 40% of the dry weight of tailings) was examined, and a comparison was made on samples prepared at the same fly ash content by replacing gold tailings with humic acid (i.e., gold tailings and humic acid ratios of 100:0, 90:10, and 80:20 by weight) or by varying pore fluid chemistry (i.e., water and salt solutions of 1M NaCl and CaCl2). The results show that the initial thermal conductivity of the samples is sensitive to the mixture proportion and a declination in the thermal conductivity is observed due to hydration of fly ash and evaporation. Inclusion of fly ash and salts into gold tailings improves the unconfined compressive strength but the presence of humic acid in samples leads to the decrease of the strength. MIP results reveal the pore structure changes associated with the packing states of the samples that reflect the influential factors considered. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Utilization of open pit burned household waste ash--a feasibility study in Dhaka.

    Science.gov (United States)

    Haque, Md Obaidul; Sharif, Ahmed

    2014-05-01

    Informal incineration or open pit burning of waste materials is a common practice in the peripheral area of Dhaka, one of the fastest growing mega-cities in the world. This study deals with the effect of open pit burned (i.e. open burned) household waste bottom ash on fired clay bricks. Between 0 to 50% (by weight) of open pit burned household waste bottom ash was mixed with clay to make bricks. The molded specimens were air-dried at room temperature for 24 h and then oven dried at 100 °C for another 24 h to remove the water. The raw bricks were fired in a muffle furnace to a designated temperature (800, 900 and 1000 °C, respectively). The firing behaviour (mechanical strength, water absorption and shrinkage) was determined. The microstructures, phase compositions and leachates were evaluated for bricks manufactured at different firing temperatures. These results demonstrate that open pit burned ash can be recycled in clay bricks. This study also presents physical observations of the incinerated ash particles and determination of the chemical compositions of the raw materials by wet analysis. Open pit burned ash can be introduced easily into bricks up to 20% wt. The concentrations of hazardous components in the leachates were below the standard threshold for inert waste category landfill and their environmental risk during their use-life step can be considered negligible.

  19. Radioisotopic assays of CoASH and carnitine and their acetylated forms in human skeletal muscle

    International Nuclear Information System (INIS)

    Cederblad, G.; Carlin, J.I.; Constantin-Teodosiu, D.; Harper, P.; Hultman, E.

    1990-01-01

    Radioisotopic assays for the determination of acetyl-CoA, CoASH, and acetylcarnitine have been modified for application to the amount of human muscle tissue that can be obtained by needle biopsy. In the last step common to all three methods, acetyl-CoA is condensed with [14C]oxaloacetate by citrate synthase to give [14C]-citrate. For determination of CoASH, CoASH is reacted with acetylphosphate in a reaction catalyzed by phosphotransacetylase to yield acetyl-CoA. In the assay for acetylcarnitine, acetylcarnitine is reacted with CoASH in a reaction catalyzed by carnitine acetyltransferase to form acetyl-CoA. Inclusion of new simple steps in the acetylcarnitine assay and conditions affecting the reliability of all three methods are also described. Acetylcarnitine and free carnitine levels in human rectus abdominis muscle were 3.0 +/- 1.5 (SD) and 13.5 +/- 4.0 mumol/g dry wt, respectively. Values for acetyl-CoA and CoASH were about 500-fold lower, 6.7 +/- 1.8 and 21 +/- 8.9 nmol/g dry wt, respectively. A strong correlation between acetylcarnitine (y) and short-chain acylcarnitine (x), determined as the difference between total and free carnitine, was found in biopsies from the vastus lateralis muscle obtained during intense muscular effort, y = 1.0x + 0.5; r = 0.976

  20. Risk to ash from emerald ash borer: can biological control prevent the loss of ash stands?

    Science.gov (United States)

    Jian J. Duan; Roy G. Van Driesche; Leah S. Bauer; Daniel M. Kashian; Daniel A. Herms

    2015-01-01

    Ash trees (Fraxinus spp.) are an important components of both natural forests and urban plantings in the United States and Canada (Federal Register, 2003; Nowak et al., 2003). There are approximately 16 species of Fraxinus native to North America (Harlow et al., 1996; USGS, 2014), each adapted to different ecological niches across...

  1. Main characteristics of the radioactive enrichment in ashes produced in coal-fired power stations

    International Nuclear Information System (INIS)

    Baeza, Antonio; Corbacho, Jose A.; Cancio, David; Robles, Beatriz; Mora, Juan C.

    2008-01-01

    Under contract with the Spain's 'Nuclear Safety Council', a study is being conducted of the nation's largest nominal output coal-fired power stations. Its purpose is to assess the radiological impact on workers and local populations due to this source of NORM activity. One of the aspects of particular interest is the study of the radioactive enrichment in the combustion wastes relative to the different coals used as fuel (usually local bituminous coal or lignite, or imported coal). These wastes consist of fly ash (mostly fine particles collected in electrostatic precipitators), and bottom ash (larger in size, and collected wet or dry in hoppers below the boilers). In general terms, the enrichment factors measured were between 2 and 18 for the radionuclides 40 K, 226 Ra, 232 Th, and 210 Po. The magnitude of this enrichment factor depended mainly on the ash content of each coal, and hence on the type of coal used as fuel and the specific operation cycle in the different power stations. For the radionuclides 40 K, 226 Ra, and 232 Th, the enrichment was relatively similar in value in the fly and bottom ashes produced by the different types of coal used in the power stations studied. For 210 Po, however, as was expected, the enrichment was much greater in the fly ash than in the bottom ash for each coal analyzed. (author)

  2. Use of lignite fly ash as an additive in alkaline stabilisation and pasteurisation of wastewater sludge

    Energy Technology Data Exchange (ETDEWEB)

    Kocaer, F.O.; Alkan, U.; Baskaya, H.S. [Uludag University, Bursa (Turkey). Faculty of Engineering & Architecture

    2003-10-01

    The possibility of using lignite fly ash in low doses for reducing the pathogen levels in wastewater sludge was investigated. The results showed that using fly ash alone in doses of 40%,80% and 120% (on a dry weight basis), did not produce an alkaline environment for an efficient removal of pathogens. However, using fly ash in conjunction with the minimum amount of quicklime may act as an effective way of fecal coliform removal in both alkaline stabilisation and pasteurisation processes. It was shown that using fly ash in doses of 80% and 120% in alkaline stabilisation and pasteurisation processes prevented the pH decays and regrowth of pathogens during 60 days of storage period. The results of the study confirmed that alkaline pasteurisation process produces a product which is more resistant to pH decays and regrowth of fecal coliforms compared to that of alkaline stabilisation. Consequently, the overall results of this study indicated that the minimum lime and fly ash dosages required to generate a Class B biosolid were 10-15% and 80%, respectively. On the other hand, heating sludge to 50{degree}C prior to the addition of 10-15% quicklime and 80% fly ash followed by further heating to 70{degree}C and then sustaining at this temperature for 30 minutes were sufficient to generate a Class A biosolid.

  3. The durability of fired brick incorporating textile factory waste ash and basaltic pumice

    Energy Technology Data Exchange (ETDEWEB)

    Binici, Hanifi [Kahramanmaras Sutcu Imam Univ., Kahramanmaras (Turkey). Dept. of Civil Engineering; Yardim, Yavuz [Epoka Univ., Tirana (Albania). Dept. of Civil Engineering

    2012-07-15

    This study investigates the durability of fired brick produced with additives of textile factories' waste ash and basaltic pumice. The effects of incorporating waste ash and basaltic pumice on durability and mechanical properties of the clay bricks were studied. Samples were produced with different ratios of the textile factories' waste ash and basaltic pumice added and at different fire temperatures of 700, 900, and 1 050 C for 8 h. The bricks with additives were produced by adding equal amounts of textile factories' waste ash and basaltic pumice, separately and together, with rates of 5, 10 and 20 wt.%. The produced samples were kept one year in sodium sulphate and sodium nitrate and tested under freezing - unfreezing and drying - wetting conditions. Then compression strength and mass loss of the samples with and without additives were investigated. The test results were compared with standards and results obtained from control specimens. The results showed that incorporations up to 10 wt.% of textile factories' waste ash and basaltic pumice is beneficial to the fired brick. Both textile factories' waste ash and basaltic pumice were suitable additives and could be used for more durable clay brick production at 900 C fire temperature. (orig.)

  4. Fly ash as a binder in aggregate base courses

    International Nuclear Information System (INIS)

    Zenieris, P.; Laguros, J.G.

    1988-01-01

    The benefit of adding up to 35 wt% Class C high calcium fly ash to various types of fine and coarse aggregate pavement mixes is described and quantified. The mixes, which were compacted to maximum dry density at optimum moisture content, had variable compressive strengths during the first 28 day of curing; after that they assumed a relatively uniform pattern of strength gain reaching values as high as 11 MPa (1600 psi). Mixes containing 15% fly ash gave unacceptably low strengths. XRD measurements indicated massive formation of ettringite, transforming to monosulfoaluminate and the poorly crystallized hydrated phases of C-A-H, C-A-S-H and C-S-H. This transformation helps explain the gain in strength of the mixes with extended curing. SEM observations depicted progressive packing and densification of the skeletal matrix as the hexagonal phases and C-S-H gained higher crystallinity and formed aggregate masses. Furthermore, these observations suggest that fly ash acts predominantly as a chemical binder and partly as a filler in the aggregate mixes tested

  5. Preparation Of Pure Carbon From Heavy Oil Fly Ash

    International Nuclear Information System (INIS)

    ABU ZAID, A.H.M.

    2010-01-01

    The Egyptian production of heavy oil is approximately 12 million tons of heavy oil per year and approximately 5.3 million tons of this amount is used as fuel in the electric power stations. Based on the fact that the ash content of Egyptian heavy oil is approximately 0.2 %, about 10600 tons of fly ash is produced per/year which causes a lot of environmental problems such as dusting, release of the acidic liquids and heavy metals such as vanadium, nickel, zinc and unburned carbon. Treatment of fly ash by leaching of vanadium and zinc was carried out under different conditions to achieve the best leaching efficiency of both vanadium and zinc by sodium hydroxide. The leaching efficiency obtained was 91% for vanadium and 98% for zinc. This study was concerned with the precipitation of zinc at pH 7.5 as zinc hydroxide and the precipitation of vanadium as ammonium metavanadate at pH 8.5. Leaching of nickel, iron and other elements from the residue was carried out by 2M HCl under different conditions. The achieved leaching efficiency of nickel was 95% where as that of iron was 92%. Precipitation efficiency of both nickel and iron were 99.9%. The residue, which contains mainly unburned carbon, have been washed two times with water and dried at 200 o C then ground to < 300μm. According to the achieved analysis of the obtained carbon, it can be characterized as pure carbon

  6. Effect of fly-ash amended soil on growth of Lactuca sativa L

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, K.; Farooqui, A.; Kulshreshtha, K.; Ahmad, K.J. [National Botanical Research Institute, Lucknow (India). Environmental Botany Lab.

    1995-04-01

    The present study has been undertaken with a view to evaluate the impact of fly-ash amended soil on growth and photosynthetic pigments of Lactuca sativa L. It was seen that 10% treatment showed marked increase in plant growth while 20-30% treated plants showed retarded growth as compared to control. Similar trends of increase and decrease in pigment formation was also observed. Results indicate the utilization of fly-ash in low concentrations for better growth, dry matter production and increased photosynthetic pigments.

  7. Radiochemical studies on Bikini ashes

    Energy Technology Data Exchange (ETDEWEB)

    Shiokawa, T

    1954-01-01

    Decay characteristics of the ashes which were brought back by the crew of the Fukuryu Maru No. 5 were: untreated ash I = ct/sup -1/ /sup 81/, water soluble part t/sup -2/ /sup 71/, insoluble part t/sup -1/ /sup 68/. Radioactive species separated by chemical method with carrier or collector were: nuclide, activity of nuclide (counts/min)/activity of original sample (counts/min), and the date of separation, /sup 89/Sr 6000/80 X 10/sup 4/, April 24; /sup 95/Zr, 280/80 x 10/sup 4/, -; /sup 111/Ag, 200/200 x 10/sup 4/, April 14; /sup 103/Ru, 2.300/25 x 10/sup 4/, etc.

  8. The Ashes of Marci Shore

    Directory of Open Access Journals (Sweden)

    Zbigniew Kopeć

    2013-01-01

    Full Text Available The article discusses Marci Shore’s social and historical thought, as presented in her books: Caviar and Ashes: A Warsaw Generation’s Life and Death in Marxism, 1918-1968 (2006, The Taste of Ashes (2013, and her essays recently published in Polish translation. The author follows the American historian, presenting her concept of modernity, but focuses on the main theme of her research: the contribution of Jewish writers, poets, artists, and intellectuals to the creation of Marxism. The author acknowledges the great value of Marci Shore’s writings, but argues that her panorama of the 20th century would be fuller if her discussion included a reflection on the religious attitude of many Jewish thinkers to Marxism and the USSR. This topic was discussed by Nikolai Berdyaev and Polish thinkers who published in pre-war social journals.

  9. Removal of uranium from simulated fly ash by chloride volatilization method

    International Nuclear Information System (INIS)

    Nobuaki, Sato; Yoshikatsu, Tochigi; Toshiki, Fukui; Takeo, Fujino

    2003-01-01

    Fly ash is generated from LWR nuclear power plant as a low-level waste, which is contaminated with a small amount of radioactive materials, composed mainly of uranium oxide. The constituents of the fly ash are similar to those of the ore; the major components of the ash are oxides of silicon, aluminum, sodium, magnesium, zinc, iron sodium and uranium. In this study, removal of uranium from the simulated fly ash, of which composition was U 3 O 8 : 10, CaO:25, SiO 2 : 25, Al 2 O 3 : 20, MgO: 10, ZnO:5, Fe 2 O 3 : 3 and Na 2 CO 3 : 2 wt%, by chloride volatilization method was examined. The simulated fly ash was chlorinated by the same manner as the dry way processing for the ore; namely, the ash was heated in a flow of chlorine in the presence of carbon at high temperatures. In the case of volatilization of uranium from U 3 O 8 and a simulated fly ash by chlorination using chlorine and carbon, it was seen that uranium of both samples showed similar volatilization behaviour: The volatilization ratio of uranium (VU) increased with increasing temperature from 800 to 1100 C. The VU value attained 99.9% at 1100 C. Iron, silicon and zinc showed similar behaviour to uranium, namely, they vaporized completely. The volatilization ratio of aluminum, magnesium and sodium were still high in a range 80-90%. The volatilization ratio of calcium was ∼40% under the same chlorination condition, though it changed to chloride. For recovery of uranium from fly ash by chlorination using chlorine in the presence of carbon, high volatilization ratio of uranium can be achieved at high temperatures. Volatilization ratio of other components also increases, which decreases the amount of decontaminated residue resulting in the reducing of decontamination effect. Selection of heating condition is important. (author)

  10. Effect of Rice Husk Ash on Cement Stabilized Laterite

    Directory of Open Access Journals (Sweden)

    Musa ALHASSAN

    2007-09-01

    Full Text Available Laterite soil collected from Maikunkele area of Minna, classified as an A-7-6 on AASHTO classification, was stabilized with 2-8% cement by weight of the dry soil. Using British Standard Light (BSL compaction energy, the effect of Rice Husk Ash (RHA on the soil was investigated with respect to compaction characteristics, California Bearing Ratio (CBR and Unconfined Compressive Strength (UCS tests. Results obtained, indicate a general decrease in Maximum Dry Density (MDD and increase in Optimum Moisture Content (OMC, all with increase in RHA Content (2-8% at specified cement contents. There was also a tremendous improvement in the CBR and UCS with increase in the RHA content at specified cement contents to their peak values at between 4-6% RHA. The UCS values also improved with curing age. This indicates the potentials of using 4-6% RHA admixed with less cement contents for laterite soil stabilization.

  11. Life cycle adaption of biofuel ashes. Evaluation of new techniques for pelletizing of biofuel ashes, especially regarding operational properties and environmental effects in the forest after ash recycling. Stage 1

    International Nuclear Information System (INIS)

    Loevgren, Linnea; Lundmark, Jan-Erik; Jansson, Charlotta

    2000-11-01

    greater acid neutralisation capacity. Wood ash differs from lime in that it contains a substantial amount of nutrient elements essential for the forest. The acid neutralisation capacity of the roll pelleted ash was still the same after 100 days of laboratory leaching. The acid neutralisation capacity of self-hardened and crushed ashes usually ceases already after 30 days. It is likely that a well-hardened roll pelleted ash product can, without any great risk of serious damage to ground vegetation, be recycled to the forest during the clearcut stage as a compensation fertiliser following biofuel harvesting. Neither increased nitrification nor leaching of nitrate from soil water is likely to occur. Potassium is considered to be an element that is easily leached from ash. In our laboratory leaching study, on the other hand, as much as 61 % of the original potassium content was still present in the roll pelleted ash after 100 days. The roll pelleting machine has been running a little more than six months at the two mills. In total 1500 tonnes of pellets have been produced. The main part is pellets solely from ash, however, mixtures of ash and lime sludge and ash and green liquor sludge, respectively, have also been pelleted. Our experiences of the roll pelleting machine are very good. The ash products seem well suited to recycling back to the forest. The machine has a production capacity of five tonnes per hour, indicating a production capacity of 10,000 tonnes per year. The running costs, including costs for personnel, spare parts and internal transports, amounted to 87 SEK per tonne of dry ash (i.e. 61 SEK per tonne of ash with 30 % water content) during the long term test. These are low costs compared to other agglomeration techniques. The roll pelleting technique has worked very well on a large scale without any further technical development. As this machine was the first of its kind some adjustments and minor changes were made in the machine and container during the

  12. Utilization technology on slurried ash

    Energy Technology Data Exchange (ETDEWEB)

    Kanbe, Yoshio; Yasuda, Minoru; Furuki, Yasuhiko [The Coal Mining Research Centre, Japan, Tokyo, Japan; Electric Power Development Co., Ltd., Tokyo (Japan))

    1987-08-01

    Three research results of the utilization technology on slurried ash were reported. As for the utilization as the fly ash quick setting (FQS) backfill grout for tail void in shield works of tunneling, grout blending was simplified, the blended solution of cement, clay, additives and water was stabilized, and a favorable workability and long term durability were obtained. As for the utilization as the material of a SMW (soil mixing wall) method for continuous walls in long shaft digging, a fly ash-gypsum-cement (FGC) stabilizer showed an excellent workability and remarkably high water-tightness as compared with conventional cement bentonite. As for the utilization as the material of an injection method of overlay mats in foundation works of light weight structures on the sea bed mud foundation, since a FGC concrete weight in water was remarkably light as 0.7t/m{sup 3}, no both large mold form strength and vibration compacting were required. 10 figs., 8 tabs.

  13. Producing zeolites from fly ash

    International Nuclear Information System (INIS)

    Rayalu, S.; Labhestwar, N.K.; Biniwale, R.B.; Udhoji, J.S.; Meshram, S.U.; Khanna, P.

    1998-01-01

    Fly ash has virtually become a menace of thermal power generation, leading to its devastating effects on the environment. Development of alternate methods of its disposal - especially those with recourse to recovery of valuable materials-has thus become imperative. This paper deals with the utilisation of fly ash for the production of high value-added products, viz., commercial grade zeolites. The physico-chemical and morphological characteristics of fly ash based Zeolite-A (FAZ-A) compares well with commercial Zeolite-A. High calcium binding capacity, appropriate particle/pore size and other detergency characteristics of FAZ-A brings forth its potential as a substitute for phosphatic detergent builder. The technology is extremely versatile, and other products like Zeolite-X, Zeolite-Y, sodalite and mordenite are also amenable for cost effective production with modifications in certain reaction parameters. Low temperature operations, ready availability of major raw materials, simplicity of process and recycling of unused reactants and process water are special features of the process. (author)

  14. False deformation temperatures for ash fusibility associated with the conditions for ash preparation

    Energy Technology Data Exchange (ETDEWEB)

    Wall, T.F.; Gupta, S.K.; Gupta, R.P.; Sanders, R.H.; Creelman, R.A.; Bryant, G.W. [University of Newcastle, Callaghan, NSW (Australia). Cooperative Research Centre for Black Coal Utilization, Dept. of Chemical Engineering

    1999-07-01

    A study was made to investigate the fusibility behaviour of coal ashes of high ash fusion temperatures. Coals and ashes formed in the boiler were sampled in several Australian power stations, with laboratory ashes being prepared from the coals. The laboratory ashes gave lower values for the deformation temperature (DT) than the combustion ashes when the ash had low levels of basic oxide components. Thermo-mechanical analysis, quantitative X-ray diffraction and scanning electron microscopy were used to establish the mechanisms responsible for the difference. Laboratory ash is finer than combustion ash and it includes unreacted minerals (such as quartz, kaolinite and illite) and anhydrite (CaSO{sub 4}). Fusion events which appear to be characteristic of reacting illite, at temperatures from 900 to 1200{degree}C, were observed for the laboratory ashes, these being associated with the formation of melt phase and substantial shrinkage. The combustion ashes did not contain this mineral and their fusion events were observed at temperatures exceeding 1300{degree}C. The low DTs of coal ashes with low levels of basic oxides are therefore a characteristic of laboratory ash rather than that found in practical combustion systems. These low temperatures are not expected to be associated with slagging in pulverised coal fired systems. 10 refs., 3 figs., 2 tabs.

  15. Arsenic, chromium and mercury removal using mussel shell ash or a sludge/ashes waste mixture.

    Science.gov (United States)

    Seco-Reigosa, Natalia; Peña-Rodríguez, Susana; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Sanjurjo, María J; Alvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2013-04-01

    Different batches of valued mussel shell and waste mussel shell ash are characterised. Shell ash has pH > 12 and high electrical conductivities (between 16.01 and 27.27 dS m(-1)), while calcined shell shows pH values up to 10.7 and electrical conductivities between 1.19 and 3.55 dS m(-1). X-ray fluorescence, nitric acid digestion and water extractions show higher concentrations in shell ash for most parameters. Calcite is the dominant crystalline compound in this ash (95.6%), followed by aragonite. Adsorption/desorption trials were performed for mussel shell ash and for a waste mixture including shell ash, sewage sludge and wood ash, showing the following percentage adsorptions: Hg(II) >94%, As(V) >96% and Cr(VI) between 11 and 30% for shell ash; Hg(II) >98%, As(V) >88% and Cr(VI) between 30 and 88% for the waste mixture. Hg and As desorption was ash and the waste mixture, while Cr desorption was between 92 and 45% for shell ash, and between 19 and 0% for the mixture. In view of that, mussel shell ash and the mixture including shell ash, sewage sludge and wood ash could be useful for Hg(II) and As(V) removal.

  16. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Stories Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es el ojo seco? ...

  17. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es el ojo seco? ...

  18. Proceedings of symposium on ash in North America

    Science.gov (United States)

    Charles H. Michler; Matthew D., eds. Ginzel

    2010-01-01

    Includes 5 papers and 30 abstracts covering topics related to the biology and ecology of the ash species, ash utilization and management, emerald ash borer, and other threats to ash, and genetics and conservation of ash species. A paper titled "Population-level variation of Fraxinus americana L. is influenced by climate...

  19. Study over problems related to fuel and ash handling systems; Probleminventering braensle- och askhantering

    Energy Technology Data Exchange (ETDEWEB)

    Njurell, Rolf; Wikman, Karin [AaF-Energi och Miljoe AB, Stockhom (Sweden)

    2003-10-01

    There have been a lot of problems related to fuel and ash handling systems since the combustion of different types of biofuels started in the 70s. Many measures have been taken to solve some of the problems, but others have become part of the daily work. The purpose of this study has been to do a compilation of the fuel and ash handling problems that exist at different types of heat and power plants. The study over problems related to fuel and ash handling systems has been carried out through a questionnaire via the Internet. Directors at about 150 energy production plants were contacted by phone or e-mail in the beginning of the project and asked to participate in the study. 72 of these plants accepted to fill in the questionnaire. After several reminders by e-mails and phone calls there were in the end 32 plants that completed the form. Together they reported about 25 problems related to fuel handling and 27 problems related to ash handling. In general each of the plants reported one problem of each kind. Even if the material from the questionnaire is not enough to make statistical analysis a few conclusions can be made about the most common problems, the cause of the problems and where they appear. Fuel handling problems that occur at several plants are stoppage in the conveying equipment, bridging in the boiler silo or the tipping bunker and problems with the sieve for separation. The distribution of the fuel handling problems is almost equal for all equipment parts (receiving, separation, transport etc.). For the ash handling systems problems with transport of dry bottom ash dominate, followed by and the moistening of fly ash and transport of wet bottom ash. Most of the problems related to fuel handling are caused by the fuel quality. For example several plants have reported that bark is a fuel that is hard to handle. Nevertheless the quality for a specific fuel is not always bad when it is delivered to the plant but the fuel quality might change during

  20. Composites Based on Fly Ash and Clay

    International Nuclear Information System (INIS)

    Fidancevska, E.; Jovanov, V.; Angusheva, B.; Srebrenkoska, V.

    2014-01-01

    Fly ash is a waste generated from the coal combustion during the production of electricity in the thermal power plants. It presents industrial by-product containing Technologically Enhanced Natural Occurring Radioactive Materials (TENORM) with the great potential for valorisation. Fly ash is successfully utilized in cement and concrete industry, also in ceramics industry as component for manufacturing bricks and tiles, and recently there are many investigations for production of glass-ceramics from fly ash. Although the utilization of fly ash in construction and civil engineering is dominant, the development of new alternative application for its further exploitation into new products is needed. This work presents the possibility for fly ash utilization for fabricating dense composites based on clay and fly ash with the potential to be used in construction industry

  1. Possibilities of utilizing power plant fly ashes

    Directory of Open Access Journals (Sweden)

    Mezencevová Andrea

    2003-09-01

    Full Text Available The burning of fossil fuels in industrial power stations plays a significant role in the production of thermal and electrical energy. Modern thermal power plants are producing large amounts of solid waste, mainly fly ashes. The disposal of power plant waste is a large environmental problem at the present time. In this paper, possibilities of utilization of power plant fly ashes in industry, especially in civil engineering, are presented. The fly ash is a heterogeneous material with various physical, chemical and mineralogical properties, depending on the mineralogical composition of burned coal and on the used combustion technology. The utilization of fly ashes is determined of their properties. The fineness, specific surface area, particle shape, density, hardness, freeze-thaw resistance, etc. are decisive. The building trade is a branch of industry, which employs fly ash in large quantities for several decades.The best utilization of fluid fly ashes is mainly in the production of cement and concrete, due to the excellent pozzolanic and cementitious properties of this waste. In the concrete processing, the fly ash is utilized as a replacement of the fine aggregate (fine filler or a partial replacement for cement (active admixture. In addition to economic and ecological benefits, the use of fly ash in concrete improves its workability and durability, increases compressive and flexural strength, reduces segregation, bleeding, shrinkage, heat evolution and permeability and enhances sulfate resistance of concrete.The aim of current research is to search for new technologies for the fly ash utilization. The very interesting are biotechnological methods to recovery useful components of fly ashes and unconventional methods of modification of fly ash properties such as hydrothermal zeolitization and mechanochemical modification of its properties. Mechanochemistry deals with physico - chemical transformations and chemical reactions of solids induced by

  2. Hospital waste ashes in Portland cement mortars

    International Nuclear Information System (INIS)

    Genazzini, C.; Zerbino, R.; Ronco, A.; Batic, O.; Giaccio, G.

    2003-01-01

    Nowadays, most concretes incorporate mineral additions such as pozzolans, fly ash, silica fume, blast furnace slag, and calcareous filler among others. Although the technological and economical benefits were the main reasons for the use of mineral additions, the prevention of environmental contamination by means of proper waste disposal becomes a priority. The chance of incorporating hospital waste ashes in Portland cement-based materials is presented here. Ash characterization was performed by chemical analysis, X-ray diffraction, radioactive material detection, and fineness and density tests. Conduction calorimetry and setting time tests were developed on pastes including ash contents from 0% to 100%. Mortars were prepared including ash contents up to 50% of cement. The results of setting time, temperature development, flexural and compressive strengths, water absorption, density, and leachability are analyzed. Results indicate that Portland cement systems could become an alternative for the disposal of this type of ashes

  3. Processed bottom ash for replacing fine aggregate in making high-volume fly ash concrete

    OpenAIRE

    Antoni; Sulistio Aldi Vincent; Wahjudi Samuel; Hardjito Djwantoro; Hardjito Djwantoro

    2017-01-01

    Bottom ash is a coal plant by-product that is abundant and underutilized. There is the potential use of bottom ash as a fine aggregate replacement in concrete mixtures; however, the problems of water absorption and uniformity of quality of the material need to be overcome first. In this study, bottom ash was treated by sieve separation and pounding to smaller particle size for use as a sand substitute. The physical and chemical characteristics of bottom ash were tested after treatment includi...

  4. Hydration of fly ash cement and microstructure of fly ash cement pastes

    Energy Technology Data Exchange (ETDEWEB)

    Shiyuan, H.

    1981-01-01

    The strength development and hydration of fly ash cement and the influence of addition of gypsum on those were studied at normal and elevated temperatures. It was found that an addition of a proper amount of gypsum to fly ash cement could accelerate the pozzolanic reaction between CH and fly ash, and as a result, increase the strength of fly ash cement pastes after 28 days.

  5. Utilization of Hospital Waste Ash in Concrete

    Directory of Open Access Journals (Sweden)

    Shazim Ali Memon

    2013-01-01

    Full Text Available Hospital waste management is a huge problem in Pakistan. The annual production of medical waste produced from health care facilities, in Pakistan, is around 250,000 tons. This research paper is intended to evaluate the feasibility of using of hospital waste ash obtained from Pakistan Institute of Medical Sciences, Rawalpindi, Pakistan, as partial replacement of cement. The main variable in this research is the amount of hospital waste ash (2, 4, 6 and 8% by weight of cement while the amount of cementitious material, water to cementitious material ratio, fine and coarse aggregate content were kept constant. Test results substantiate that hospital waste ash can be used in concrete. XRD (X-Ray Diffraction of hospital waste ash showed that it is rich in calcite while scanning electron micrographs indicated that the particles of hospital waste ash have highly irregular shape. The slump value, density of fresh concrete and water absorption decreased with the increase in the quantity of hospital waste ash in the mix. At 3 days of testing, the compressive strength of mixes with hospital waste ash was higher than the control mix while at 7 and 28 days the CM (Control Mix showed higher strength than the hospital waste ash mixes except the mix containing 2% hospital waste ash by weight of cement.

  6. Method of reversibly immobilizing sulfate ash

    International Nuclear Information System (INIS)

    Greenhalgh, W.O.

    1984-01-01

    A sulphate ash at least 20% by weight of which consists of sulphates of transuranic elements is immobilised by heating to melting a mixture of the ash, a metal, and a fluxing agent; the metal used is Al, Ce, Sm, Eu or mixtures thereof and it is used in an amount sufficient to reduce the transuranic sulphates in the ash to metal and form an alloy with the metal so produced; sufficient of the fluxing agent is used to reduce the percentage of transuranic sulphates in the mix to form 1% to 10% of the mix and the molten mixture is cooled and the alloy containing the immobilised ash separated. (author)

  7. Utilization of hospital waste ash in concrete

    International Nuclear Information System (INIS)

    Memon, S.; Sheikh, M.

    2013-01-01

    Hospital waste management is a huge problem in Pakistan. The annual production of medical waste produced from health care facilities, in Pakistan, is around 250,000 tons. This research paper is intended to evaluate the feasibility of using of hospital waste ash obtained from Pakistan Institute of Medical Sciences, Rawalpindi, Pakistan, as partial replacement of cement. The main variable in this research is the amount of hospital waste ash (2, 4, 6 and 8% by weight of cement) while the amount of cementitious material, water to cementitious material ratio, fine and coarse aggregate content were kept constant. Test results substantiate that hospital waste ash can be used in concrete. XRD (X-Ray Diffraction) of hospital waste ash showed that it is rich in calcite while scanning electron micrographs indicated that the particles of hospital waste ash have highly irregular shape. The slump value, density of fresh concrete and water absorption decreased with the increase in the quantity of hospital waste ash in the mix. At 3 days of testing, the compressive strength of mixes with hospital waste ash was higher than the control mix while at 7 and 28 days the CM (Control Mix) showed higher strength than the hospital waste ash mixes except the mix containing 2% hospital waste ash by weight of cement. (author)

  8. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Jensen, Peter Arendt; Wu, Hao

    2016-01-01

    . Therefore, timely removal of ash deposits is essential for optimal boiler operation. In order to improve the qualitative and quantitative understanding of deposit shedding in boilers, this study investigates the shear adhesion strength of biomass ash deposits on superheater tubes. Artificial biomass ash...... deposits were prepared on superheater tubes and sintered in an oven at temperatures up to 1000 °C. Subsequently, the deposits were sheared off by an electrically controlled arm, and the corresponding adhesion strength was measured. The results reveal the effect of temperature, ash/deposit composition......, sintering duration, and steel type on the adhesion strength....

  9. Hazards Associated With Recent Popocatepetl Ash Emissions

    Science.gov (United States)

    Nieto, A.; Martin, A.; Espinasa-Pereña, R.; Ferres, D.

    2013-05-01

    Popocatepetl has been producing ash from small eruptions since 1994. Until 2012 about 650 small ash emissions have been recorded at the monitoring system of Popocatépetl Volcano. Ash consists mainly of glassy lithic clasts from the recent crater domes, plagioclase and pyroxene crystals, and in major eruptions, olivine and/or hornblende. Dome forming eruptions produced a fine white ash which covers the coarser ash. This fine ash consists of plagioclase, glass and cristobalite particles mostly under15 microns. During the recent crisis at Popocatépetl, April and May2012 ash fell on villages to the east and west of the volcano, reaching Mexico City (more than 20 million people) and Puebla (2 million people). In 14 cases the plumes had heights over 2 km, the largest on May 2 and 11 (3 and 4 km in height, respectively). Heavier ash fall occurred on April 13, 14, 20, and 23 and May 2, 3, 5, 11, 14, 23, 24 and 25. A database for ash fall was constructed from April 13 with field observations, reports emitted by the Centro Nacional de Comunicaciones (CENACOM), ash fall advisories received at CENAPRED and alerts from the Servicios a la Navegación en el Espacio Aéreo Mexicano (SENEAM). This aim of this database is to calculate areas affected by the ash and estimate the ash fall volume emitted by Popocatépetl in each of these events. Heavy ash fall from the May 8 to May 11 combined with reduced visibility due to fog forced to closure of the Puebla airport during various periods of time, for up to 13 hours. Domestic and international flights were cancelled. Ash eruptions have caused respiratory conditions in the state of Puebla, to the east of the volcano, since 1994 (Rojas et al, 2001), but because of the changing wind conditions in the summer mainly, some of these ash plumes go westward to towns in the State of Mexico and even Mexico City. Preliminary analyses of these eruptions indicate that some ash emissions produced increased respiratory noninfectious problems

  10. Stabilization of Clay Soil Using Tyre Ash

    Directory of Open Access Journals (Sweden)

    Mahmood Dheyab Ahmed

    2017-06-01

    Full Text Available The planning, designing, construction of excavations and foundations in soft to very soft clay soils are always difficult. They are problematic soil that caused trouble for the structures built on them because of the low shear strength, high water content, and high compressibility. This work investigates the geotechnical behavior of soft clay by using tyre ash material burnt in air. The investigation contains the following tests: physical tests, chemical tests, consolidation test, Compaction tests, shear test, California Bearing Ratio test CBR, and model tests. These tests were done on soil samples prepared from soft clay soil; tyre ash was used in four percentages (2, 4, 6, and 8%. The results of the tests were; The soil samples which gave the value of plasticity test were 2% (25, 4% (25.18, 6% (25.3, and 8% (26.7.The soil samples which gave the value of specific gravity were 2% (2.65, 4% (2.61, 6% (2.5, and 8% (2.36.The value of maximum dry density in a compaction test observed with 2% percentage gave the value 15.8 kN/m3, the 4% gave the value 15.4 kN/m 3 34 , 6% gave 15.3 kN/m 3 and 8%with 15.2 kN/m3 .Samples that gave the values of undrained shear strength test were 2% (55 kN/m 2 , 4% (76 kN/m2 , 6% (109 kN/m 2, and 8% (122 kN/m 2. The best of them is 8%. The sample that gave the best value for swelling test was 8%.The best value for compression index Cc was in 8%.The results of CBR test, were improved in all soil samples. The soil samples which gave the value for CBR were 2% (3.507%, 4% (4.308%, 6% (5.586%, and 8% (9.569%. The best value was obtained from 8%.

  11. Attraction of the emerald ash borer to ash trees stressed by girdling, herbicide treatment, or wounding

    Science.gov (United States)

    Deborah McCullough; Therese Poland; David. Cappaert

    2009-01-01

    New infestations of emerald ash borer, Agrilus planipennis Fairmaire, an invasive pest native to Asia, are difficult to detect until densities build and symptoms appear on affected ash (Fraxinus spp). We compared the attraction of A. planipennis to ash trees stressed by girdling (bark and phloem removed...

  12. The Role of Biocontrol of Emerald Ash Borer in Protecting Ash Regeneration after Invasion

    Science.gov (United States)

    Emerald ash borer (EAB) is an invasive Asian beetle that is destroying ash in forests over much of eastern North America because of the high susceptibility of our native ash and a lack of effective natural enemies. To increase mortality of EAB larvae and eggs, the USDA (FS, ARS and APHIS) is carryin...

  13. Factors affecting the survival of ash (Fraxinus spp.) trees infested by emerald ash borer (Agrilus planipennis)

    Science.gov (United States)

    Kathleen S. Knight; John P. Brown; Robert P. Long

    2013-01-01

    Emerald ash borer (Agrilus planipennis) (EAB), an Asian woodboring beetle accidentally introduced in North America, has killed millions of ash (Fraxinus spp.) trees and is spreading rapidly. This study examined the effects of tree- and site-level factors on the mortality of ash trees in stands infested by EAB in OH, USA. Our data...

  14. Use of unwounded ash trees for the detection of emerald ash borer adults: EAB landing behavior

    Science.gov (United States)

    Jordan M. Marshall; Melissa J. Porter; Andrew J. Storer

    2011-01-01

    Incorporation of multiple trapping techniques and sites within a survey program is essential to adequately identify the range of emerald ash borer (EAB) (Agrilus planipennis Fairmaire) infestation. Within natural forests, EAB lands on stick band traps wrapped around girdled ash trees at a rate similar to that on unwounded ash trees. The objective of...

  15. Survey for tolerance to emerald ash borer within North American ash species

    Science.gov (United States)

    Jennifer L. Koch; Mary E. Mason; David W. Carey; Kathleen Knight; Therese Poland; Daniel A. Herms

    2010-01-01

    Since the discovery of the emerald ash borer (EAB) near Detroit, MI, in 2002, more than 40 million ash trees have been killed and another 7.5 billion are at risk in the United States. When the EAB outbreak was initially discovered, our native ash species appeared to have no resistance to the pest.

  16. Characterization of ashes of elephant grass (Pennisetum purpureum) for potential added in mass red ceramic

    International Nuclear Information System (INIS)

    Silva, A.M.F.D.; Sales, K.A.; Monteiro, S.N.; Vieira, C.M.F.

    2012-01-01

    This work is in characterizing ash from biomass grass (Pennisetum purpureums) for incorporation into red ceramic masses. The ashes of elephant grass were generated from burning this dry biomass in an industrial furnace of red ceramic. The morphology of the material generated was observed by an optical microscope. The chemical composition was determined by fluorescence X-ray spectrometry, and the identification of phases by X-ray diffraction. The particle size distribution was obtained by sieving. Thermogravimetric analyzes were also conducted. The results indicate that these ashes are constituted of high quantities of SiO 2 , MgO, CaO and K 2 O, totaling approximately 75% of composition of matter. They have a particle size of 0.7 to 2.2mm featuring. The residue as a kind of coarse particles. Therefore, the results of this study can support future research to the addition of this residue in structural ceramics products (red ceramic)

  17. Geopolymer obtained from coal ash; Geopolimeros obtidos a partir de cinzas de carvao mineral

    Energy Technology Data Exchange (ETDEWEB)

    Conte, V.; Bissari, E.S.; Uggioni, E.; Bernardin, A.M., E-mail: amb@unesc.net [Universidade do Extremo Sul Catarinense (UNESC), Criciuma, SC (Brazil). Grupo de Materiais Ceramicos e Vitreos

    2011-07-01

    Geopolymers are three-dimensional alumino silicates that can be rapidly formed at low temperature from naturally occurring aluminosilicates with a structure similar to zeolites. In this work coal ash (Tractebel Energy) was used as source of aluminosilicate according a full factorial design in eight formulations with three factors (hydroxide type and concentration and temperature) and two-levels. The ash was dried and hydroxide was added according type and concentration. The geopolymer was poured into cylindrical molds, cured (14 days) and subjected to compression test. The coal ash from power plants belongs to the Si-Al system and thus can easily form geopolymers. The compression tests showed that it is possible to obtain samples with strength comparable to conventional Portland cement. As a result, temperature and molarity are the main factors affecting the compressive strength of the obtained geopolymer. (author)

  18. Properties of cement-fly ash grout admixed with bentonite, silica fume, or organic fiber

    International Nuclear Information System (INIS)

    Huang, W.H.

    1997-01-01

    A detailed laboratory study was conducted to investigate the properties of cement-fly ash grout mixtures as barriers for isolation of hazardous and low-level radioactive wastes. In the grout studied, fly ash was used to replace 30 percent by mass of cement. Three additives including bentonite, silica fume, and polypropylene fiber were used individually in the grout mixes to improve the properties of the grouts in different aspects. The flowability, bleeding, and setting time of freshly mixed grouts were determined; and the unconfined compressive strength, pore size distribution, and water permeability were determined for hardened grouts at various curing durations up to 120 days. Finally, the durability of cement-fly ash grouts was carefully examined in terms of the changes in their physical properties after different levels of exposure to sulfate attack and wet-dry cycles

  19. The agronomic landspreading of coal bottom ash: using a regulated solid waste as a resource

    Energy Technology Data Exchange (ETDEWEB)

    Sell, N; McIntosh, T; Severance, C; Peterson, A

    1989-02-01

    Within the US, approximately 8860 Mg of dry coal bottom ash is generated daily, the majority of which is disposed of by landfilling. The disposal cost varies significantly depending on location. In Wisconsin, for example, in 1987 public landfill disposal costs ranged from 8.90 US dollars to 30 US dollars per Mg. However, bottom ash appears to be an acceptable soil amendment which may alter texture and improve tilth by making clay soils more friable and decreasing crust formation. If a generic exemption for this material can be developed with the appropriate regulatory bodies, use of coal bottom ash as a soil amendment has societal and economic advantages. This paper describes the key point of an agronomic management plant. An economic comparison indicates that, based on 1987 costs, agronomic use is only 38% as costly as landfill disposal. 14 refs., 5 tabs.

  20. Geo-environmental application of municipal solid waste incinerator ash stabilized with cement

    Directory of Open Access Journals (Sweden)

    Davinder Singh

    2017-04-01

    Full Text Available The behavior of soluble salts contained in the municipal solid waste incinerator (MSWI ash significantly affects the strength development and hardening reaction when stabilized with cement. The present study focuses on the compaction and strength behavior of mixed specimens of cement and MSWI ash. A series of indices such as unconfined compressive strength, split tensile strength, California bearing ratio (CBR and pH value was examined. Prior to this, the specimens were cured for 7 d, 14 d, and 28 d. The test results depict that the maximum dry density (MDD decreases and the optimum moisture content (OMC increases with the addition of cement. The test results also reveal that the cement increases the strength of the mixed specimens. Thus, the combination of MSWI ash and cement can be used as a lightweight filling material in different structures like embankment and road construction.

  1. The behaviour of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M.H.; Abelha, P.; Lapa, N.; Oliveira, J.S.; Cabrita, I.; Gulyurtlu, I. [INETI, Lisbon (Portugal)

    2003-07-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC with the aim of characterizating the ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials.

  2. A Study on the Evaluation of Field Application of High-Fluidity Concrete Containing High Volume Fly Ash

    Directory of Open Access Journals (Sweden)

    Yun-Wang Choi

    2015-01-01

    Full Text Available In the recent concrete industry, high-fluidity concrete is being widely used for the pouring of dense reinforced concrete. Normally, in the case of high-fluidity concrete, it includes high binder contents, so it is necessary to replace part of the cement through admixtures such as fly ash to procure economic feasibility and durability. This study shows the mechanical properties and field applicability of high-fluidity concrete using mass of fly ash as alternative materials of cement. The high-fluidity concrete mixed with 50% fly ash was measured to manufacture concrete that applies low water/binder ratio to measure the mechanical characteristics as compressive strength and elastic modulus. Also, in order to evaluate the field applicability, high-fluidity concrete containing high volume fly ash was evaluated for fluidity, compressive strength, heat of hydration, and drying shrinkage of concrete.

  3. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett [Park City, UT

    2012-05-15

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with a quantity of spray dryer ash (SDA) and water to initiate a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 40%, and in some cases less than 20%, of the foam index of the untreated fly ash. An optional alkaline activator may be mixed with the fly ash and SDA to facilitate the geopolymerization reaction. The alkaline activator may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  4. Optimization of soil stabilization with class C fly ash.

    Science.gov (United States)

    1987-01-01

    Previous Iowa DOT sponsored research has shown that some Class : C fly ashes are cementitious (because calcium is combined as calcium : aluminates) while other Class C ashes containing similar amounts of : elemental calcium are not (1). Fly ashes fro...

  5. 10 Risk to Ash from Emerald Ash Borer: Can Biological Control Prevent the Loss of Ash Stands

    Science.gov (United States)

    Ash trees were once relatively free of serious, major diseases and insect pests in North America until the arrival of EAB, which was first detected in North America in Michigan in 2002. As of February 2014, EAB had been detected in 22 U.S. states and two Canadian provinces, killing millions of ash ...

  6. Cementing Efficiency of Low Calcium Fly Ash in Fly Ash Concretes

    OpenAIRE

    T. D. Gunneswara Rao; Mudimby Andal

    2014-01-01

    Research on the utilization of fly ash will no longer refer the fly ash as a waste material of thermal power plants. Use of fly ash in concrete making, makes the concrete economical as well as durable. The fly ash is being added to the concrete in three ways namely, as partial replacement to cement, as partial replacement to fine aggregates and as admixture. Addition of fly ash to the concrete in any one of the form mentioned above, makes the concrete more workable and durable than the conven...

  7. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye? Dry Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Inside of Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  8. What Is Dry Eye?

    Science.gov (United States)

    ... Eye? Dry Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Inside of Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  9. Electrodialytic removal of heavy metals from fly ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul

    2002-01-01

    The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration.......The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration....

  10. Improving lithium-ion battery performances by adding fly ash from coal combustion on cathode film

    Energy Technology Data Exchange (ETDEWEB)

    Dyartanti, Endah Retno; Jumari, Arif, E-mail: arifjumari@yahoo.com; Nur, Adrian; Purwanto, Agus [Research Group of Battery & Advanced Material, Department of Chemical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A Kentingan, Surakarta Indonesia 57126 (Indonesia)

    2016-02-08

    A lithium battery is composed of anode, cathode and a separator. The performance of lithium battery is also influenced by the conductive material of cathode film. In this research, the use of fly ash from coal combustion as conductive enhancer for increasing the performances of lithium battery was investigated. Lithium iron phosphate (LiFePO{sub 4}) was used as the active material of cathode. The dry fly ash passed through 200 mesh screen, LiFePO{sub 4} and acethylene black (AB), polyvinylidene fluoride (PVDF) as a binder and N-methyl-2-pyrrolidone (NMP) as a solvent were mixed to form slurry. The slurry was then coated, dried and hot pressed to obtain the cathode film. The ratio of fly ash and AB were varied at the values of 1%, 2%, 3%, 4% and 5% while the other components were at constant. The anode film was casted with certain thickness and composition. The performance of battery lithium was examined by Eight Channel Battery Analyzer, the composition of the cathode film was examined by XRD (X-Ray Diffraction), and the structure and morphology of the anode film was analyzed by SEM (Scanning Electron Microscope). The composition, structure and morphology of cathode film was only different when fly ash added was 4% of AB or more. The addition of 2% of AB on cathode film gave the best performance of 81.712 mAh/g on charging and 79.412 mAh/g on discharging.

  11. Kinetics of fly ash beneficiation by carbon burnout. Quarterly report, July 1--September 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Dodoo, J.N.D.; Okoh, J.M.; Diaz, A.

    1998-08-01

    Oxidation studies of coal fly ash have been carried out at partial pressures in the range 1 atmosphere down to 400 torr. The studies have also been carried out at 1 atmosphere for different temperatures in the range 500 to 750 C. The equipment used was a state-of-the-art Cann Thermogravimetric analyzer having sensitive microbalance that permitted measurements to .1 {micro}g. The analyzer is part of a GC/MS/TG setup in this laboratory. The fly ash was supplied by Delmarva Power Indian River Plant, DE. The samples were dried and stored in a desiccator to ensure that they remained dry prior to combustion. The combustion process inside the TGA is continuous and the heat released can be related to the percent of carbon consumed. The setup provided easy identification of the elements in the fly ash. The elemental analysis was also augmented by use of an energy dispersive X-ray analyzer. In the X-ray analysis the carbon in the fly ash was compared with that in a dolomite (CaMg(CO{sub 3}){sub 2}) standard obtained from the US Bureau of Mines (USBOM). Preliminary data show encouraging results in the rate of reduction of the residual carbon. Both analyses show reduction of carbon after burning.

  12. Possibility of using waste tire rubber and fly ash with Portland cement as construction materials.

    Science.gov (United States)

    Yilmaz, Arin; Degirmenci, Nurhayat

    2009-05-01

    The growing amount of waste rubber produced from used tires has resulted in an environmental problem. Recycling waste tires has been widely studied for the last 20 years in applications such as asphalt pavement, waterproofing systems and membrane liners. The aim of this study is to evaluate the feasibility of utilizing fly ash and rubber waste with Portland cement as a composite material for masonry applications. Class C fly ash and waste automobile tires in three different sizes were used with Portland cement. Compressive and flexural strength, dry unit weight and water absorption tests were performed on the composite specimens containing waste tire rubber. The compressive strength decreased by increasing the rubber content while increased by increasing the fly ash content for all curing periods. This trend is slightly influenced by particle size. For flexural strength, the specimens with waste tire rubber showed higher values than the control mix probably due to the effect of rubber fibers. The dry unit weight of all specimens decreased with increasing rubber content, which can be explained by the low specific gravity of rubber particles. Water absorption decreased slightly with the increase in rubber particles size. These composite materials containing 10% Portland cement, 70% and 60% fly ash and 20% and 30% tire rubber particles have sufficient strength for masonry applications.

  13. Flight potential of the emerald ash borer

    Science.gov (United States)

    Leah S. Bauer; Deborah L. Miller; Robin A.J. Taylor; Robert A. Haack

    2004-01-01

    The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive pest of ash trees (Fraxinus spp.) in North America. Native to several Asian countries, EAB was discovered in six southeastern Michigan counties and southwestern Ontario in 2002. EAB presumably emerged from infested solid wood...

  14. Biology of emerald ash borer parasitoids

    Science.gov (United States)

    Leah S. Bauer; Jian J. Duan; Jonathan P. Lelito; Houping Liu; Juli R. Gould

    2015-01-01

    The emerald ash borer (EAB) (Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), an invasive beetle introduced from China (Bray et al., 2011), was identified as the cause of ash (Fraxinus spp.) mortality in southeast Michigan and nearby Ontario in 2002 (Haack et al., 2002; Federal Register, 2003; Cappaert et al., 2005)....

  15. Wet physical separation of MSWI bottom ash

    NARCIS (Netherlands)

    Muchova, L.

    2010-01-01

    Bottom ash (BA) from municipal solid waste incineration (MSWI) has high potential for the recovery of valuable secondary materials. For example, the MSWI bottom ash produced by the incinerator at Amsterdam contains materials such as non-ferrous metals (2.3%), ferrous metals (8-13%), gold (0.4 ppm),

  16. Coal combustion ashes: A radioactive Waste?

    International Nuclear Information System (INIS)

    Michetti, F.P.; Tocci, M.

    1992-01-01

    The radioactive substances naturally hold in fossil fuels, such as Uranium and Thorium, after the combustion, are subjected to an increase of concentration in the residual combustion products as flying ashes or as firebox ashes. A significant percentage of the waste should be classified as radioactive waste, while the political strategies seems to be setted to declassify it as non-radioactive waste. (Author)

  17. Laboratory rearing of emerald ash borer

    Science.gov (United States)

    Leah S. Bauer; Robert A. Haack; Deborah L. Miller; Houping Liu; Toby Petrice

    2004-01-01

    The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), native to several Asian countries, was identified in 2002 as the cause of ash (Fraxinus spp.) mortality throughout southeastern Michigan and southwestern Ontario. More isolated infestations continue to be found throughout Lower Michigan, northern...

  18. Emerald ash borer survival in firewood

    Science.gov (United States)

    Robert A. Haack; Toby R. Petrice

    2005-01-01

    The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is native to Asia and was first discovered in Michigan and Ontario in 2002. As of October 2004, EAB was only found to breed in ash (Fraxinus) trees in North America. EAB is spreading naturally through adult flight as well as artificially through...

  19. Emerald ash borer biology and invasion history

    Science.gov (United States)

    Robert A. Haack; Yuri Baranchikov; Leah S. Bauer; Therese M. Poland

    2015-01-01

    The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is native to eastern Asia and is primarily a pest of ash (Fraxinus) trees (Fig. 1). Established populations of EAB were first detected in the United States and Canada in 2002 (Haack et al., 2002), and based on a dendrochronology study by Siegert...

  20. Evaluation of atomic absorption Spectrophotometry (ashing, non ...

    African Journals Online (AJOL)

    Three commonly used techniques, namely atomic absorption spectrophotometry (AAS-Ashing and AAS-Non Ashing) and titrimetry (potassium permanganate titration) have been evaluated in this study to determine the calcium content in six food samples whose calcium levels ranged from 0 to more than 250mg/100g ...

  1. Potassic zeolites from Brazilian coal ash for use as a fertilizer in agriculture.

    Science.gov (United States)

    Flores, Camila Gomes; Schneider, Helena; Marcilio, Nilson Romeu; Ferret, Lizete; Oliveira, João Carlos Pinto

    2017-12-01

    Brazilian coal has an ash content ranging from 30 to 50% by weight. Consequently, its use in coal-fired thermoelectric for power production generates a lot of waste. The construction sector is the largest consumer of coal ash, but it cannot absorb the entire amount generated. Thus, other applications for coal ash should be studied in aim to optimize the use of this industrial waste. This research had as focus to synthesize potassic zeolite from of the coal ash into on potassium fertilizer for the grown wheat plant. In this work, it was used a subbituminous coal from Mina do Leão (RS, Brazil) presenting 48.7% ash content on a dry basis. Concerning the synthesis of potassic zeolite, it was adopted the conventional method of hydrothermal treatment with potassium hydroxide. A schedule of experiments was conducted in order to define the optimum condition of zeolite synthesis that was then used an alkaline solution of 5M KOH with a reaction time of 24h at 150°C. According to this procedure, it was obtained a zeolite with a single crystalline phase, identified through X-ray diffraction as Merlinoite. Subsequently, it was performed a set of tests using potassic zeolite asa fertilizer for plants in a greenhouse. The synthesized potassic zeolite showed a good potential for its use as fertilizer in agriculture. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. The Stabilization of Weathered Dolerite Aggregates with Cement, Lime, and Lime Fly Ash for Pavement Construction

    Directory of Open Access Journals (Sweden)

    Felix N. Okonta

    2014-01-01

    Full Text Available An experimental program was performed on weathered dolerite specimens stabilized by adding varying percentages of cement (4, 8, 12, and 16 % and lime (6 and 12 % and a combination of lime and fly ash (6% lime + 12% Fly ash and 12% lime + 12% Fly ash % by dry weight of soil. The strength was examined under three different curing methods, namely, membrane curing (MBC, alternate moist-air curing (MAC, and water curing (WAC, by conducting unconfined compressive strength (UCS tests. Simple polynomial and linear functions (regression models were used to define the relationships between the variables investigated. Membrane curing (MBC gave results close enough to the water curing (WAC to indicate that it can be confidently used on the field during pavement construction. From the results obtained, for class B (interurban collector and major rural roads pavement construction, addition of 8% cement was recommended for road base construction with stabilized WDA. Also the addition of 12 + 12% Lime and Fly Ash was recommended for road subbase construction with stabilized WDA. Stabilized WDA against the prejudiced myths would perform satisfactorily for base and subbase construction in both heavily trafficked and low volume roads with economic quantities of cement, lime, and fly ash in South Africa.

  3. Determining ash content in flotation wastes by means of the MPOF optical ash meter. [Poland

    Energy Technology Data Exchange (ETDEWEB)

    Sikora, T; Sliwa, J

    1982-03-01

    The paper evaluates an experimental unit of the MPOF optical ash meter, developed by the EMAG Research and Production Center for Electrical Engineering and Mining Automation. The MPOF, which is being tested at the coal preparation plant of the 30 lecia PRL mine, is the first system for continuous determination of ash content in flotation tailings developed in Poland. A block scheme of the system is given. It consists of a measuring head and electronic system which processes data supplied by the measuring head and calculates ash content. System operation is based on the principle of determining ash content in a mixture of coal and mineral wastes by measuring mixture reflectivity. Determining ash content in the mixture is possible as reflectivity coefficients for coal and ash are constant. Performance of the MPOF optical ash meter is evaluated; the results are shown in a table and a scheme. Measurement accuracy is satisfactory.

  4. Design of a hydraulic ash transport system

    Energy Technology Data Exchange (ETDEWEB)

    Mirgorodskii, V.G.; Mova, M.E.; Korenev, V.E.; Grechikhin, Yu.A. (Donetskii Politekhnicheskii Institut (USSR))

    1990-04-01

    Discusses general design of a hydraulic ash removal system to be employed at the reconstructed six 225 MW blocks of the Mironov State Regional Power Plant in the USSR. The blocks burn low-grade solid fuel with an ash content of up to 40.5%. Large quantities of ash have to be moved from the plant (total ash production 60 t/h, using 570 t/h of water for cooling and moistening). An optimum hydraulic ash transportation system would include a two-section airlift pumping system, shown in a diagram. Technological advantages of using this airlift system are enumerated, including short pipes, reduction in required water quantity and the possibility of siting hydraulic pumps at zero level.

  5. Environmental considerations on the FBC combustion of dry sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M. Helena; Abelha, Pedro; Gulyurtlu, Ibrahim; Cabrita, Isabel [INETI/DEECA, Lisboa (Portugal)

    2001-07-01

    This paper presents results of on-going research on the incineration of pre-dried granular sewage sludges using a FBC system. Co-combustion is compared with mono-combustion of sludges leads to minor emissions and higher retention of Cd, Pb, Cu, and Zn in the bottom ashes, when compared to co-combustion with coal. The leachability of the sludge is reduced through combustion, as none of the metals, Cd, Cr, Ca Ni, Ph, Zn, Co and Mn were leached from the bottom ashes. These findings may contribute to an improvement in the incineration of sewage sludges and to the development of applications for the ashes in civil engineering activities.

  6. Properties and Leachability of Self-Compacting Concrete Incorporated with Fly Ash and Bottom Ash

    Science.gov (United States)

    Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Jamaluddin, Norwati; Bakri Abdullah, Mohd Mustafa Al

    2016-06-01

    The process of combustion in coal-fired power plant generates ashes, namely fly ash and bottom ash. Besides, coal ash produced from coal combustion contains heavy metals within their compositions. These metals are toxic to the environment as well as to human health. Fortunately, treatment methods are available for these ashes, and the use of fly ash and bottom ash in the concrete mix is one of the few. Therefore, an experimental program was carried out to study the properties and determine the leachability of selfcompacting concrete incorporated with fly ash and bottom ash. For experimental study, self-compacting concrete was produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a replacement for sand with the ratios of 10%, 20%, and 30% respectively. The fresh properties tests conducted were slump flow, t500, sieve segregation and J-ring. Meanwhile for the hardened properties, density, compressive strength and water absorption test were performed. The samples were then crushed to be extracted using Toxicity Characteristic Leaching Procedure and heavy metals content within the samples were identified accordingly using Atomic Absorption Spectrometry. The results demonstrated that both fresh and hardened properties were qualified to categorize as self-compacting concrete. Improvements in compressive strength were observed, and densities for all the samples were identified as a normal weight concrete with ranges between 2000 kg/m3 to 2600 kg/m3. Other than that, it was found that incorporation up to 30% of the ashes was safe as the leached heavy metals concentration did not exceed the regulatory levels, except for arsenic. In conclusion, this study will serve as a reference which suggests that fly ash and bottom ash are widely applicable in concrete technology, and its incorporation in self-compacting concrete constitutes a potential means of adding value to appropriate mix and design.

  7. Investigation on Leaching Behaviour of Fly Ash and Bottom Ash Replacement in Self-Compacting Concrete

    Science.gov (United States)

    Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

    2016-06-01

    Fly ash and bottom ash are some of the waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. In recent years, many researchers have been interested in studying on the properties of self-compacting concrete incorporated with fly ash and bottom ash but there was very limited research from the combination of fly ash and bottom ash towards the environmental needs. Therefore, this research was focused on investigating the leachability of heavy metals of SCC incorporated with fly ash and bottom ash by using Toxicity Characteristic Leaching Procedure, Synthetic Precipitation Leaching Procedure and Static Leaching Test. The samples obtained from the coal-fired power plant located at Peninsula, Malaysia. In this study, the potential heavy metals leached out from SCC that is produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a substitute for sand with the ratios from 10% to 30% respectively were designated and cast. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results indicated that most of the heavy metals leached below the permissible limits from the United States Environmental Protection Agency and World Health Organization limit for drinking water. As a conclusion, the minimum leaching of the heavy metals from the incorporation of fly ash and bottom ash in self-compacting concrete was found in 20% of fly ash and 20% of bottom ash replacement. The results also indicate that this incorporation could minimize the potential of environmental problems.

  8. Ash from Straw and Grain - Chemical Composition, Physical Properties and Technique for Spreading; Aska fraan halm och spannmaal - kemisk sammansaettning, fysikaliska egenskaper och spridningsteknik

    Energy Technology Data Exchange (ETDEWEB)

    Marmolin, Christina; Ugander, Joakim; Gruvaeus, Ingemar; Lundin, Gunnar

    2008-07-01

    oats produce 150-200 kg of ash. Ash from combusted oats from a 3.5 MW power plant in the region of Uppsala and ash from a 20 kW on-farm plant were analysed with respect to particle size distribution, bulk density, moisture content and angle of repose. The ash from the large power plant was also used in a practical spreading test in which a lime spreader and a manure spreader were evaluated. Moisture content of the ash had a great impact on physical properties. Dry ash directly from the furnace consisted to 70% of particles smaller than 0.4 mm and the ash was very dusty. Ash that had been stored outdoors had a moisture content of about 32-35% and contained large clods up to 40 cm in length and also aggregates of finer particles similar to moist gravel. This ash was dust-free. In the evaluation of the spreaders, the ash was collected using boxes measuring 0.5 x 0.5 m and placed with a c-c spacing of 1-2 m across the full spreading width of the spreaders. The results showed that the ash was difficult to handle in both dry and moist condition. The lime spreader had difficulties in achieving a uniform material flow when presented with the moist ash. The uneven flow from the loading bin to the spreader discs also caused variations in the spreading width. It was evident that appropriate mixing and crushing of large clods in the ash before spreading was crucial if acceptable uniformity of spreading we re to be achieved. The lime spreader had a major drawback in that the speed of the spreading discs was synchronised with the speed of the feeder belt from the loading bin. It was therefore impossible to reduce the spreading rate without affecting the spreading width. Using dry ash with the lime spreader produced an M-shaped spreading pattern that was probably caused by the direction of rotation of the spreading discs, which were set for moist material. Another problem with spreading of dry ash with the lime spreader was that the casting width was limited to 10 m, and the

  9. Statistical Analysis of the Effects of Drying Temperature and Pretreatment on the Proximate Composition of Dried Matured Green Plantain (Musa Paradisiaca

    Directory of Open Access Journals (Sweden)

    K.A. Yusuf

    2014-07-01

    Full Text Available Drying has been identified as the efficient means of ensuring continuous food supply to the growing population of any country and to enable the farmers produce more high quality marketable products. In this study, the effects of drying temperature and pretreatment on the quality of dried mature green plantain (Musa paradisiaca were studied using an electrically-powered cabinet dryer. The product was dried from an initial moisture content of 62% (w.b to a moisture content of 11.9% (w.b. A factorial experiment in a Randomized Complete Block Design (RCBD involving three levels of temperature (50, 60 and 70 0C; three levels of pretreatment (blanching, boiling and control and three replications were used. The quality analysis of the dried samples at different level of drying temperatures and pre-treatments was carried out for protein, fat, ash and fibre content and the data obtained were statistically analyzed using SPSS 16.0 software to determine the level of significance among the treatment factors on the dried samples. The protein, fat and fibre content decreased with increase in temperature but the ash content increased with increase in temperature. In pretreatments, control had the highest protein content of 4.27% at 60 0C, lowest fat content of 2.26% at 70 0 C and moderate fibre and ash contents of 0.68% and 1.82% respectively at 60 0C. Boiled sample also had the highest fat content of 4.27% at 50 0C, lowest fat content 2.26% at 70 0C and moderate fibre and ash contents of 0.88% and 1.73% respectively at 60 0C. lastly, blanched sample had the highest fat content of 4.11% at 50 0 C, lowest fat content 2.54% at 70 0C and moderate fibre and ash contents of 0.83% and 1.45% respectively at 60 0C.

  10. Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, H.K.; Kristensen, I.V.; Ottosen, L.M.; Villumsen, A. [Dept. of Geology and Geotechnical Engineering, The Technical Univ. of Denmark, Lyngby (Denmark)

    2001-07-01

    Electroosmotic dewatering has been tested in laboratory cells for 4 different porous materials: chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge from enzyme production. In all cases it was possible to remove water when passing electric DC current through the material. Casagrande's coefficients for the three materials where determined at different water contents. In the electroosmotic experiments shown in this work chalk can be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM. The process was not optimised indicating that higher dry matter contents could be achieved. (orig.)

  11. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Ophthalmology/Strabismus Ocular Pathology/Oncology Oculoplastics/Orbit Refractive Management/Intervention Retina/Vitreous Uveitis Focus On ... Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms Causes of ...

  12. Ash and heavy metals in fluidized-bed combustion of wood wastes; Tuhka ja raskasmetallit puuperaeisen jaetteen kerrosleijupoltossa

    Energy Technology Data Exchange (ETDEWEB)

    Kaessi, T; Aittoniemi, P [IVO Power Engineering, Vantaa (Finland); Kauppinen, E; Latva-Somppi, J; Kurkela, J [VTT Chemical Technology, Espoo (Finland); Partanen, J [IVO Technology Centre, Vantaa (Finland)

    1997-10-01

    Ash formation and deposition mechanisms during co-combustion of pulp mill sludge and bark in industrial bubbling fluidized bed (BFB) combustor have been studied. Similar fuels were used in a bench-scale BFB for co-combustion of sludge and bark pellets and comparative studies with separate combustion of these fuels. Results indicated that in industrial scale unit significant fraction of ash had vaporization. About 14 mass-% of the total fly ash was found in the particle size below 0.2 {mu}m. The vaporized species consisted of potassium (K), sulfur (S), chlorine (Cl) and also of minor quantities of sodium (Na). In the benchscale similar vaporization fractions during co-combustion were measured, about 11 mass-%. During the combustion of bark this ratio, about 20 mass-%, was higher than during sludge combustion. The vaporized ash fraction was in the case of dried sludge combustion about 7 mass-%, but with wet sludge the vaporization rate was remarkably lower, about 1-2 mass-%. An increase in the bed temperature increased also ash vaporization. Test run period without combustion at elevated temperatures produced very low quantities of vaporized ash. The vaporized species in bench-scale test during bark pellet combustion were K, S and Cl, for sludge combustion also Na was clearly detected. No condensation of the vaporized species in bed area or furnace walls was observed. Bed defluidization was studied in the bench-scale unit. During bark pellet combustion the bed-agglomeration proceeded via small ash particle, below 2 {mu}m, coating on sand particle surface and consequent bonding between the ash layers. In the case of sludge combustion the accumulation of large ash particles and sintering of these porous agglomerates was observed to cause bed coarsening and defluidization. (orig.)

  13. Treatment of biofuel ashes for forest recycling

    International Nuclear Information System (INIS)

    Bjurstroem, H.; Sjoeblom, R.

    1997-03-01

    Logging residues are the easiest available fuel for an increased production of energy in Sweden from renewable sources. A consequence of their removal from the forest is that the cycle of mineral nutrients is broken. The purpose of recycling the ash after this fuel to forest land is to compensate for the removal and close again the nutrient cycle. Recycling nutrients and returning the inorganic components of the biomass removed from the forest should be performed in accordance with general principles of environmental protection, health considerations and the good house-keeping of natural resources. The activities should also be carried out in accordance with the needs of the forest and energy plant owners regarding good technology and economy. This implies that functional requirements originating from these principles and needs should be clearly structured and formulated and that such requirements should provide a basis for the continued development work as well as for the implementation of suitable, economical and efficient systems. Returning inorganic constituents implies that the principle of recirculation is followed as well as that nutrients are brought back which improves accretion in the forest. At the same time, the risk of damage to the forest can be assessed as insignificant. Furthermore the risks to human health are also assessed to be insignificant provided that pertinent precautions are taken to avoid dusting. In the present report, technical and economical aspects of importance for the selection of method as well as for the establishment of a system are described and discussed. The need for further development work is identified in the following areas: functional requirements - operational requirements, sampling, testing and quality assurance, granulation, curing processes and drying/sintering. 102 refs, 1 fig, 2 tabs

  14. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    2013-01-08

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  15. Long term effects of ash fertilization of reed canary grass; Laangtidseffekter av askgoedsling vid roerflensodling

    Energy Technology Data Exchange (ETDEWEB)

    Palmborg, Cecilia; Lindvall, Eva

    2011-03-15

    Reed canary grass (RCG) is a bio-energy crop with large potential. It is a 1.5 . 2.5 m tall grass that is harvested in spring when it is grown as a fuel. At spring harvest it yields 3 . 10 ton field dried material per ha and year. One disadvantage when reed canary grass is used as a fuel is the high ash content, 5-10 %. This means that large quantities of ash have to be deposited which is expensive, about 1000 SEK/ton. However, since reed canary grass ash contains reasonable amounts of plant nutrients like phosphorous (P), potassium (K) and magnesium (Mg) it could be recycled as fertilizer in agriculture. The ash can be used without any pretreatment since, in agriculture, plant availability is desirable. The aim of this project, was to evaluate a field experiment, where ash was used as a fertilizer in reed canary grass. The experiment was established at the SLU research station in Umea, Sweden in the spring 2002. Three different fertilizer treatments were applied: Treatment A was fertilized with an ash produced by combustion of RCG together with municipal wastes (paper, plastic, leather), treatment B, an ash from combustion of RCG, and for treatment C commercial fertilizers were used. In total, 100 kg ha-1 of nitrogen (N), 15 kg ha-1 of phosphorous (P) and 80 kg ha-1 of potassium (K), were applied each year in all treatments. The amount of ash in treatment A and B was calculated from the chemical analysis of the ashes to be equal to the required amount of P, while K and N were supplied also by commercial fertilizers. [Table 1. Composition of the ashes] Literature study: There is a lack of knowledge about fertilization with reed canary grass ash, since few experiments have been conducted. The composition of reed canary grass is dependent of harvest date and the soil substrate. The amount of ash and the amount of harmful substances such as potassium and chloride generally decreases over winter, giving an increased fuel quality from spring harvest compared to autumn

  16. A rice husk gasifier for paddy drying

    International Nuclear Information System (INIS)

    Mirani, A.A.; Kalwar, S.A.; Ahmad, M.

    2013-01-01

    Due to energy crisis and constant increase in the price of fossil fuels, the world's trend changes to renewable sources of energy like solar, wind and biomass gasification. Substantial biomass potential is available in Pakistan in the form of agriculture or forest residue (rice straw, rice husk, cotton stalks, corn cobs, wood chips, wood saw, etc.). These can be best utilised for the production of producer gas or synthetic gas that can be used for drying of agricultural crops. The drying process is an important activity of post harvest processing for long-term storage. Rice husk is nowadays commonly used for biomass gasification and its heat content value is about 15MJ/kg. It constitutes about 30 percent of rice production. A rice husk gasifier was developed and evaluated on paddy drying at Japan International Cooperation Agency (JICA), Tsukuba International Center (TBIC), Japan. Rice husk gasifier has following major components; husk feeding system, ash chamber, burner, centrifugal fan, drying chamber, gasifier reactor, air duct and an electric motor of 0.37kW. The average drying plenum air temperature was recorded as 45 degree C during the drying process. The paddy 'IR 28' from initial moisture content of 24% was dried up to 14% moisture content for about 3.33h consuming 3kg/h of rice husk. The efficiency was found to be 58%. The rice husk gasifier can also be used for drying the fruits and vegetables, provided that heat exchanger should be attached with it. The overall performance of rice husk gasifier was satisfactory and will be beneficial for small scale farmers, food processors and millers as well. (author)

  17. Fly Ash in Civil Engineering Stage 1: Inventory/Application; Flygaska i geotekniska anlaeggningar Etapp 1: Inventering/Tillaemplighet

    Energy Technology Data Exchange (ETDEWEB)

    Macsik, Josef; Svedberg, Bo; Lenstroemer, Stina; Nilsson, Thomas [Scandiaconsult, Stockholm (Sweden)

    2004-01-01

    The project presented below is the first phase of a broader project named FACE 'Fly Ash in Civil Engineering'. The objective of the project is to identify environmentally friendly products based on fly ash to be used in geotechnical applications such as road bases etc. In this phase of the project, named 'Inventory/Applicability', different fly ashes have been grouped according to their technical properties and potential applications. The objective of grouping fly ashes is to identify key-properties in order to make future investigations less extensive and also to make it easier to assess potential applications in the future. A total of nine different fly ashes from incineration of bio fuels (Heating Plants and Forest Industry Boilers) were investigated. The investigated fly ashes were all fresh and dry apart from two which originated from landfill. Properties such as grain-size distribution, water content, void-ratio, loss on ignition, compaction properties, increase of shear strength, have been investigated. Analyses of the results indicate that fly ashes can be divided into three main groups A, B and C, where: Group A fly ashes have poor curing properties and need stabilisation agents such as other fly ashes with higher curing capacity or cement (Portland cement, Merit 5000 etc.). Fly ash which has been stored in landfill and has a low content of quick lime is also part of this group. These fly ashes are not appropriate for use without addition of stabilising agent if they are to be used in applications where percolating water and frost-thaw cycles occur. After stabilisation with fresh fly ash and cement, fly ashes from this group can be used in sub-base in roads. Group B fly ashes have medium-high to high content of quick lime and good development of shear strength. These fly ashes can be used without being stabilised with cement. In fact, adding cement can reduce properties of compaction thus reducing the strength of a construction. The

  18. The effect of using different sources of dry materials on waste-form grout properties

    International Nuclear Information System (INIS)

    Spence, R.D.; Gilliam, T.M.; McDaniel, E.W.

    1992-01-01

    A reference grout formulation had been developed for a liquid low-level radioactive waste using the following dry materials: ground limestone, ground granulated blast furnace slag, fly ash, and cement. The effect of varying the sources of these dry materials was tested. Two limestones, two fly ashes, two cements, and eight slags were tested. Varying the source of dry materials significantly affected the grout properties, but only the 28-d free-standing liquid varied outside of the preferred range. A statistical technique, Tukey's paired comparison, can be used to ascertain whether a given combination of dry materials resulted in grout properties significantly different from those of other combinations of dry materials. (author)

  19. SILAGE CANE SUGAR ADDED WITH DRIED BREWER

    Directory of Open Access Journals (Sweden)

    W. J. R. Castro

    2015-02-01

    Full Text Available The objective of this experiment was to evaluate the fermentative parameters and chemical composition of silage cane sugar added with residue dried brewery. The experimental design was completely randomized with four treatments and four replications: 100% cane sugar; 90% of cane sugar + 10% residue dried brewer; 80% of cane sugar + 20% residue dried brewer and 70% cane sugar + 30% dried brewer based on natural matter, composed silages. The sugar cane was chopped in a stationary machine with forage particle size of approximately 2 cm, and homogenized manually with the additives. For storage chopped fresh weight were used in experimental silos capacity of about 4 liters. The results showed that the contents of dry matter and crude protein showed positive linear (P0.05 with mean value of 3.81, while for ether extract and ash results were positive linear (P0.05 for N ammonia presented average value of 4.18. It is concluded that the addition of brewer dehydrated improves the fermentation process of silage cane sugar, in addition to improving their nutritional characteristics.

  20. Characterization of metals released from coal fly ash during dredging at the Kingston ash recovery project.

    Science.gov (United States)

    Bednar, A J; Averett, D E; Seiter, J M; Lafferty, B; Jones, W T; Hayes, C A; Chappell, M A; Clarke, J U; Steevens, J A

    2013-09-01

    A storage-pond dike failure occurred on December 22, 2008 at the Tennessee Valley Authority Kingston Fossil Plant resulting in the release of over 4million cubic meters (5million cubic yards) of fly ash. Approximately half of the released ash was deposited in the main channel of the Emory River, Tennessee, USA. Remediation efforts of the Emory River focused on hydraulic dredging, as well as mechanical excavation in targeted areas. However, agitation of the submerged fly ash during hydraulic dredging introduces river water into the fly ash material, which could promote dissolution and desorption of metals from the solid fly ash material. Furthermore, aeration of the dredge slurry could alter the redox state of metals in the fly ash material and thereby change their sorption, mobility, and toxicity properties. The research presented here focuses on the concentrations and speciation of metals during the fly ash recovery from the Emory River. Our results indicate that arsenite [As(III)] released from the fly ash material during dredging was slowly oxidized to arsenate [As(V)] in the slurry recovery system with subsequent removal through precipitation or sorption reactions with suspended fly ash material. Concentrations of other dissolved metals, including iron and manganese, also generally decreased in the ash recovery system prior to water discharge back to the river. Published by Elsevier Ltd.

  1. Processed bottom ash for replacing fine aggregate in making high-volume fly ash concrete

    Directory of Open Access Journals (Sweden)

    Antoni

    2017-01-01

    Full Text Available Bottom ash is a coal plant by-product that is abundant and underutilized. There is the potential use of bottom ash as a fine aggregate replacement in concrete mixtures; however, the problems of water absorption and uniformity of quality of the material need to be overcome first. In this study, bottom ash was treated by sieve separation and pounding to smaller particle size for use as a sand substitute. The physical and chemical characteristics of bottom ash were tested after treatment including water absorption, sieve analysis, and fineness modulus. Highvolume fly ash (HVFA mortar specimens were made and the compressive strength and flowability test using bottom ash after treatment are compared with that of the sand specimen. Low water to cementitious ratio was used to ensure higher strength from the cementitious paste and superplasticizer demand was determined for each treatment. The result showed that bottom ash can be used as fine aggregate replacement material. Sieve separation of the bottom ash could produce 75% of the compressive strength compared with the control sand specimen, whereas pounded bottom ash could have up to 96% of the compressive strength of the control specimen. A 28-day compressive strength of 45 MPa was achievable with 100% replacement of fine aggregate with bottom ash.

  2. Relationships between waste physicochemical properties, microbial activity and vegetation at coal ash and sludge disposal sites.

    Science.gov (United States)

    Woch, Marcin W; Radwańska, Magdalena; Stanek, Małgorzata; Łopata, Barbara; Stefanowicz, Anna M

    2018-06-11

    The aim of the study was to assess the relationships between vegetation, physicochemical and microbial properties of substrate at coal ash and sludge disposal sites. The study was performed on 32 plots classified into 7 categories: dried ash sedimentation ponds, dominated by a grass Calamagrostis epigejos (AH-Ce), with the admixture of Pinus sylvestris (AH-CePs) or Robinia pseudoacacia (AH-CeRp), dry ash landfill dominated by Betula pendula and Pinus sylvestris (AD-BpPs) or Salix viminalis (AD-Sv) and coal sludge pond with drier parts dominated by Tussilago farfara (CS-Tf) and the wetter ones by Cyperus flavescens (CS-Cf). Ash sites were covered with soil layer imported as a part of technical reclamation. Ash had relatively high concentrations of some alkali and alkaline earth metals, Mn and pH, while coal sludge had high water and C, S, P and K contents. Concentrations of heavy metals were lower than allowable limits in all substrate types. Microbial biomass and, particularly, enzymatic activity in ash and sludge were generally low. The only exception were CS-Tf plots characterized by the highest microbial biomass, presumably due to large deposits of organic matter that became available for aerobic microbial biomass when water level fell. The properties of ash and sludge adversely affected microbial biomass and enzymatic activity as indicated by significant negative correlations between the content of alkali/alkaline earth metals, heavy metals, and macronutrients with enzymatic activity and/or microbial biomass, as well as positive correlations of these parameters with metabolic quotient (qCO 2 ). Plant species richness and cover were relatively high, which may be partly associated with alleviating influence of soil covering the ash. The effect of the admixture of R. pseudoacacia or P. sylvestris to stands dominated by C. epigejos was smaller than expected. The former species increased NNH 4 , NNO 3 and arylsulfatase activity, while the latter reduced activity of

  3. Flue gas desulphurization in a spray tower with de-coupled recycling of soda ash

    Energy Technology Data Exchange (ETDEWEB)

    Liebgott, H.

    1983-05-01

    RD project to develop a ''dry'' process for the desulphurization of flue gases. The process is based on a desulphurization step with a solution of soda ash which is sprayed into the flue gas. The gas is cooled by evaporation but its temperature is still higher than the dew point; reheating is not necessary. The product of the desulphurization is a dry mixture of sodium sulphite and -carbonate. It is intended to reprocess this powder to soda in a central plant - serving several power stations. First sulphite is oxidized to sulphate, which in turn is reacted with calcium chloride to form calcium sulphate and sodium chloride. The latter is introduced into the Solvay-soda ash process which yields calcium chloride as a by-product. Tests were carried out for the desulphurization step and the oxidation of sulphite. The desulphurization tests resulted in poor degrees of SO/sub 2/-removal even with high stoichiometric ratios of soda ash to sulphur dioxide. The preliminary estimates of process economics made before start of experimental work could not be verified. Furthermore, during work on the project, new processes were revealed whereby flue gas is desulphurized in a spray-drying apparatus with a slurry of calcium hydroxide. In an extension of the project, tests were carried out which confirmed these findings. The project was abandoned.

  4. Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge

    DEFF Research Database (Denmark)

    Hansen, H.K.; Christensen, Iben Vernegren; Ottosen, Lisbeth M.

    2003-01-01

    . Casagrande's coefficients were determined for the four materials at different water contents. The experiments in this work showed that chalk could be dewatered from 40% to 79% DM (dry matter), fly ash from 75 to 82% DM, iron hydroxide sludge from 2.7 to 19% DM and biomass from 3 to 33% DM by electroosmosis....... The process was not optimised indicating that higher dry matter contents could be achieved by electroosmosis. It was possible to relate Casagrande's coefficient directly to the electroosmotic coefficient obtained by dewatering experiments....

  5. Gasification reactivity and ash sintering behaviour of biomass feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Moilanen, A.; Nasrullah, M.

    2011-12-15

    Char gasification reactivity and ash sintering properties of forestry biomass feedstocks selected for large-scale gasification process was characterised. The study was divided into two parts: (1) Internal variation of the reactivity and the ash sintering of feedstocks. (2) Measurement of kinetic parameters of char gasification reactions to be used in the modelling of a gasifier. The tests were carried out in gases relevant to pressurized oxygen gasification, i.e. steam and carbon dioxide, as well as their mixtures with the product gases H{sub 2} and CO. The work was based on experimental measurements using pressurized thermobalance. In the tests, the temperatures were below 1000 deg C, and the pressure range was between 1 and 20 bar. In the first part, it was tested the effect of growing location, storage, plant parts and debarking method. The following biomass types were tested: spruce bark, pine bark, aspen bark, birch bark, forestry residue, bark feedstock mixture, stump chips and hemp. Thick pine bark had the lowest reactivity (instantaneous reaction rate 14%/min) and hemp the highest (250%/min); all other biomasses laid between these values. There was practically no difference in the reactivities among the spruce barks collected from the different locations. For pine bark, the differences were greater, but they were probably due to the thickness of the bark rather than to the growth location. For the spruce barks, the instantaneous reaction rate measured at 90% fuel conversion was 100%/min, for pine barks it varied between 14 and 75%/min. During storage, quite large local differences in reactivity seem to develop. Stump had significantly lower reactivity compared with the others. No clear difference in the reactivity was observed between barks obtained with the wet and dry debarking, but, the sintering of the ash was more enhanced for the bark from dry debarking. Char gasification rate could not be modelled in the gas mixture of H{sub 2}O + CO{sub 2} + H{sub 2

  6. Assessment of soda ash calcination treatment of Turkish trona ore

    Directory of Open Access Journals (Sweden)

    Gezer Sibel

    2016-01-01

    Full Text Available Trona is relatively rare, non-metallic mineral, Na2CO3 · NaHCO3 · 2H2O. The pure material contains 70.3% sodium carbonate and by calcination the excess CO2 and water can be driven off, yielding natural soda ash. The terms soda ash and sodium carbonate are used interchangeably. Trona calcining is a key process step in production of soda ash (sodium carbonate anhydrate from the relatively cheap trona ore. The calcination reaction may proceeds in a sequence of steps. Depending on the conditions, it may result in formation of either sodium carbonate monohydrate (Na2CO3 · H2O, sodium sesquicarbonate or weigschederite (Na2CO3 · 3NaHCO3. The Beypazarı Turkish trona deposit is the second largest deposit in the world with the content of 84% trona. The decomposition of trona appeared to be a single stage process across the temperature range studied (150-200 °C with the representative samples of different size fractions in the draught up metallurgical furnace. The optimum particle size and calcination time were −6.35 mm and 30 minutes, respectively, at calcination temperature of 175 °C in a metallurgical furnace. Microwave-induced dry calcination of trona was possible and 5 minutes of calcination time at a power level of 900 was sufficient for complete calcination of −6.35 mm feed. This includes short time calcinations with the goal of improving economics and simplifying the thermal process.

  7. NEW TECHNOLOGY OF ASH AND SLAG CONCRETES

    Directory of Open Access Journals (Sweden)

    PAVLENKO T. M.

    2017-03-01

    Full Text Available Summary. Purpose. Development of scientific-technical bases of manufacture and application of concrete on the basis of ash and slag mixes of thermal power plants. Methods. It is proposed a new technology of preparation of ash and slag concrete mixes. First the ash and slag mix is dispersed through the sieve with meshes 5 mm in a fine-grained fraction and slag. Then, in accordance with the composition of the concrete, obtained fine-grained fraction, slag, cement and tempering water are separately dosed into the mixer. Results. It is proven the high efficiency of the proposed technology of manufacture of ash and slag concretes. It is established that this technological solution allows to increase the strength of concrete by 20...30%, and in the preparation of full-strength concrete to reduce the cement consumption by 15...20%. Scientific novelty. It is developed the new technology of ash and slag mixes application. The concrete mix on the basis of ash and slag mix has an optimal particle size distribution, which ensures the best compaction and, accordingly, the greatest strength of ash and slag concrete with the given cement consumption. Practical significance. The research results promote the mass application of ash and slag mixes of thermal power plants in construction, obtaining of products from the proposed concretes of low cost with high physical-mechanical properties. Conclusion. It is proven the high efficiency of the proposed technology of production of ash and slag concretes. It is established that this technological solution allows increasing concrete strength, and obtaining full-strength concrete to reduce cement consumption. The extensive application of such concrete in construction makes it possible to solve the problem of aggregates for concrete, promotes recycling of TPP waste and consequently the protection of the environment.

  8. Ash wettability conditions splash erosion in the postfire

    Science.gov (United States)

    Gordillo-Rivero, Ángel J.; de Celis, Reyes; García-Moreno, Jorge; Jiménez-Compán, Elizabeth; Alanís, Nancy; Cerdà, Artemi; Pereira, Paulo; Zavala, Lorena M.; Jordán, Antonio

    2015-04-01

    at each point of study were collected monthly and determined gravimetrically after oven drying between November 2012 and May 2013. 3. RESULTS AND DISCUSSION Depending on the intensity of the water repellency, the ash layer fluctuated between wettable and very strongly water repellent. The ash has a high permeability and water storage. However, its hydrophilic character has been emphasized rarely (Cerdà and Doerr, 2008). Different authors have described hydrophobic behaviors depending on the burned vegetation such as oak (Gabet and Sternberg, 2008) or pine forest (Stark, 1977) in the United States, eucalyptus forest in Australia (Khanna et al., 1996 ) or Mediterranean tree and shrub species in Spain (Bodí et al., 2011). In the latter case, Bodí et al. (2011) observed that ash has different properties depending on the combustion conditions, organic carbon content and color. This variability of behavior agrees with the results obtained in the present work. Significant differences between splash erosion from wettable and water-repellent ash zones were found (p authors have suggested that ash acts protecting soil from the direct impact of raindrops and thus reduce sediment dispersion by splash (Cerdà and Doerr, 2008, Larsen et al, 2009; Woods and Balfour, 2008, Zavala et al, 2009). However, there is very little information about the effect of hydrophobicity on splash erosion. In a rainfall simulation experiment under laboratory conditions, Bodí et al. (2012) observed that splash erosion was at least two times higher in samples of water repellent soil than in hydrophilic soil, but no differences in ash loss or thickness of ash layer were observed. 4. CONCLUSIONS Our results highlight the role played by ash water repellency and the influence of burn severity on the development of a pattern of splash erosion intensities. Splash erosion was reduced in one order of magnitude on wettable ash zones. In contrast, the presence of a water-repellent ash layer increases the

  9. Hypocotyl derived in vitro regeneration of pumpkin ash (Fraxinus profunda)

    Science.gov (United States)

    Micah E. Stevens; Paula M. Pijut

    2012-01-01

    Pumpkin ash (Fraxinus profunda (Bush) Bush) is at risk for extirpation by an exotic insect, the emerald ash borer (EAB). Pumpkin ash is limited to wetland areas of the Eastern United States, and has been listed as an endangered species because of EAB activity. Pumpkin ash provides many benefits to the ecosystem, and its wood is used in the...

  10. Electrodialytic removal of Cd from biomass combustion fly ash suspensions

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor M.; Ottosen, Lisbeth M.; Damoe, Anne J.

    2013-01-01

    was investigated with the aim of enabling reuse of the ashes. The ashes originated from combustion of straw (two ashes), wood chips, and co-firing of wood pellets and fuel oil, respectively. A series of laboratory scale electrodialytic remediation experiments were conducted with each ash. The initial Cd...

  11. Column leaching from biomass combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard

    2015-01-01

    The utilization of biomass combustion ashes for forest soil liming and fertilizing has been addressed in literature. Though, a deep understanding of the ash chemical composition and leaching behavior is necessary to predict potential benefits and environmental risks related to this practice....... In this study, a fly ash sample from an operating Danish power plant based on wood biomass was collected, chemically characterized and investigated for its leaching release of nutrients and heavy metals. A column leaching test was employed. The strongly alkaline pH of all the collected eluates suggested...

  12. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Jensen, Peter Arendt; Wu, Hao

    2015-01-01

    This study investigates the shear adhesion strength of biomass ash deposits on superheater tubes. Artificial biomass ash deposits were prepared on superheater tubes and sintered in an oven at temperatures up to 1000°C. Subsequently, the deposits were sheared off with the help of an electrically...... controlled arm. Higher sintering temperatures resulted in greater adhesion strengths, with a sharp increase observed near the melting point of the ash. Repetition of experiments with fixed operation conditions revealed considerable variation in the obtained adhesion strengths, portraying the stochastic...

  13. Fusibility and sintering characteristics of ash

    Energy Technology Data Exchange (ETDEWEB)

    Ots, A. A., E-mail: aots@sti.ttu.ee [Tallinn University of Technology (Estonia)

    2012-03-15

    The temperature characteristics of ash fusibility are studied for a wide range of bituminous and brown coals, lignites, and shales with ratios R{sub B/A} of their alkaline and acid components between 0.03 and 4. Acritical value of R{sub B/A} is found at which the fusion temperatures are minimal. The sintering properties of the ashes are determined by measuring the force required to fracture a cylindrical sample. It is found that the strength of the samples increases sharply at certain temperatures. The alkali metal content of the ashes has a strong effect on their sintering characteristics.

  14. Specifying and using pulverised fuel ash as an engineered fill

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, B.G.; Coombs, R. [University of Newcastle upon Tyne, Newcastle upon Tyne (United Kingdom). Dept. of Civil Engineering

    1996-12-31

    Claims arising from incorrect use of fill materials are often due to a lack of understanding of material behaviour and incomplete or wrong specifications. This is especially the case when using waste products such as pulverised fuel ash (pfa). A review of current and proposed specifications and current practice highlights some of the problems arising when selecting design parameters and acceptance criteria for pfa. Pfa can be considered a particulate material and properties of a pfa can be ascertained at the design stage because the sources are known. Design parameters are post peak effective strength parameters taken from triaxial or direct shear tests on saturated specimens compacted to 90% of the average maximum dry density. Compaction characteristics and design parameters of a particular source can be determined from tests if it is stockpiled pfa, or historical records if it is conditioned pfa. Method compaction can be used to place pfa but site trials should be carried out to determine the best method. Experience has shown that six to eight passes are sufficient, but usually the movement of construction traffic during tipping and spreading pfa will give the minimum required density. Inundation has little effect on compacted ash provided the water content is within acceptable limits, that is within 20% of the average optimum water content. 6 refs., 6 figs., 3 tabs.

  15. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  16. Drying of building lumber

    Energy Technology Data Exchange (ETDEWEB)

    Washimi, Hiroshi

    1988-08-20

    Dried lumber is classified into air dried and kiln-dried lumber. The water content of kiln-dried lumber is specified by the Japan Agricultural Standards. However, since building lumber varies in such factors as the location where it was growing, species and shape, the standards, though relaxed, are not being observed. In fact, lumbered products which are not ''Kiln-dried'' frequently bear ''kiln-dried lumber'' marks. In an attempt to correct the situation, the Forestry Agency has set up voluntary standards, but problems still remain. The conventional drying method consists of first subjecting the lumber to optimum drying, then letting bending and deformations to freely and fully appear, and follow this with corrective sawing to produce planks straight from end to end. Compared with air dried lumber in terms of moisture content, kiln-dried lumber remains much with same with minimal shrinkage and expansion. For oil-containing resin, such normal treatments as drying by heating, steaming and boiling seem to be quite effective. Kiln drying, which is becoming more and more important with changes in the circulation system, consists of the steaming-drying-heating method and the dehumidizing type drying method. The major factor which determines the drying cost is the number of days required for drying, which depends largely on the kind of lumber and moisture content. The Forestry Angency is promoting production of defoiled lumber. (2 figs, 2 tables)

  17. Outlook for ash in your forest: results of emerald ash borer research and implications for management

    Science.gov (United States)

    Kathleen S. Knight

    2014-01-01

    Since its accidental introduction near Detroit, Michigan, in the mid-1990s, emerald ash borer (EAB) has rapidly spread through much of the U.S. and adjacent Canada, leaving millions of dead ash trees in Midwestern states (4,11). Unfortunately, EAB attacks trees as small as an inch in stem diameter and it attacks all five ash species native to the region - white, green...

  18. Determining the ash content of coal flotation tailings using an MPOF optical ash meter

    Energy Technology Data Exchange (ETDEWEB)

    Sikora, T; Sliwa, J

    1982-01-01

    The block layout, a description of the design and principles of operation of an automatic optical, continuous action MPOF type ash meter are presented. The difference in the optical properties of coal and rock is used in the ash meter. The identification of the ash content is conducted on the basis of the spectral characteristics of reflection of a finely dispersed aqueous coal and rock suspension.

  19. Air pollution dry deposition: radioisotopes as particles and volatiles

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    This study focuses on determining volcanic ash and ambient airborne solids concentrations at various sampling sites subsequent to the Mt. St. Helens' eruption in order to develop an experimental basis for models predicting removal of airborne particles and gases by dry deposition onto outdoor surfaces. In addition, deposition rates were determined using dual tracer techniques in the field and in a wind tunnel in the laboratory

  20. Review of ecosystem level impacts of emerald ash borer on black ash wetlands: What does the future hold?

    Science.gov (United States)

    Randall K. Kolka; Anthony W. D' Amato; Joseph W. Wagenbrenner; Robert A. Slesak; Thomas G. Pypker; Melissa B. Youngquist; Alexis R. Grinde; Brian J. Palik

    2018-01-01

    The emerald ash borer (EAB) is rapidly spreading throughout eastern North America and devastating ecosystems where ash is a component tree. This rapid and sustained loss of ash trees has already resulted in ecological impacts on both terrestrial and aquatic ecosystems and is projected to be even more severe as EAB invades black ash-dominated wetlands of the western...

  1. Methods to Improve Survival and Growth of Planted Alternative Species Seedlings in Black Ash Ecosystems Threatened by Emerald Ash Borer

    Science.gov (United States)

    Nicholas Bolton; Joseph Shannon; Joshua Davis; Matthew Grinsven; Nam Noh; Shon Schooler; Randall Kolka; Thomas Pypker; Joseph Wagenbrenner

    2018-01-01

    Emerald ash borer (EAB) continues to spread across North America, infesting native ash trees and changing the forested landscape. Black ash wetland forests are severely affected by EAB. As black ash wetland forests provide integral ecosystem services, alternative approaches to maintain forest cover on the landscape are needed. We implemented simulated EAB infestations...

  2. Project ash cultch: A report on optimal oyster cultch based on a prepared fly ash substratum

    International Nuclear Information System (INIS)

    Price, K.S.; Hansen, K.M.; Schlekat, C.E.

    1991-01-01

    Based on a three year study involving setting, growth, mortality, oyster condition, and metals accumulation, the evidence is extensive and convincing that stabilized coal ash is an acceptable oyster growing cultch (substratum). Oyster larvae are attracted to set on coal ash cultch at commercial fishery densities, tend to grow as well as on natural substrata (oyster shell), and are moderately more exposed to predators on the puck shaped ash materials as produced for this study. Oysters grown for one to two years on coal ash do not accumulate heavy metals and generally are in good health as measured by several biological condition indexes

  3. Biotic and abiotic factors affect green ash volatile production and emerald ash borer adult feeding preference.

    Science.gov (United States)

    Chen, Yigen; Poland, Therese M

    2009-12-01

    The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an exotic woodborer first detected in 2002 in Michigan and Ontario and is threatening the ash resource in North America. We examined the effects of light exposure and girdling on green ash (Fraxinus pennsylvanica Marsh) volatile production, and effects of light exposure, girdling, and leaf age on emerald ash borer adult feeding preferences and phototaxis. Green ash seedlings grown under higher light exposure had lower amounts of three individual volatile compounds, (Z)-3-hexenol, (E)-beta-ocimene, and (Z,E)-alpha-farnesene, as well as the total amount of six detected volatile compounds. Girdling did not affect the levels of these volatiles. Emerald ash borer females preferred mature leaves, leaves from girdled trees, and leaves grown in the sun over young leaves, leaves from nongirdled trees, and leaves grown in the shade, respectively. These emerald ash borer preferences were most likely because of physical, nutritional, or biochemical changes in leaves in response to the different treatments. Emerald ash borer females and males showed positive phototaxis in laboratory arenas, a response consistent with emerald ash borer preference for host trees growing in sunlight.

  4. Performance evaluation of cement-stabilized pond ash-rice husk ash-clay mixture as a highway construction material

    Directory of Open Access Journals (Sweden)

    Deepak Gupta

    2017-02-01

    Full Text Available This paper reports the results of an investigation carried out on clay soil stabilized with pond ash (PA, rice husk ash (RHA and cement. Modified Proctor compaction tests were performed in order to investigate the compaction behavior of clay, and California bearing ratio (CBR tests were performed to determine the strength characteristics of clay. For evaluation purpose, the specimens containing different amounts of admixtures were prepared. Clay was replaced with PA and RHA at a dosage of 30%–45% and 5%–20%, respectively. The influence of stabilizer types and dosages on mechanical properties of clay was evaluated. In order to study the surface morphology and crystallization characteristics of the soil samples, scanning electron microscopy (SEM and X-ray diffraction (XRD analyses were carried out, respectively. The results obtained indicated a decrease in the maximum dry density (MDD and a simultaneous increase in the optimum moisture content (OMC with the addition of PA and RHA. Multiple linear regression analysis (MLRA showed that the predicted values of CBR tests are in good agreement with the experimental values. Developed stabilized soil mixtures showed satisfactory strength and can be used for construction of embankments and stabilization of sub-grade soil. The use of locally available soils, PA, RHA, and cement in the production of stabilized soils for such applications can provide sustainability for the local construction industry.

  5. Producing New Composite Materials by Using Tragacanth and Waste Ash

    OpenAIRE

    Yasar Bicer; Serif Yilmaz

    2013-01-01

    In present study, two kinds of thermal power plant ashes; one the fly ash and the other waste ash are mixed with adhesive tragacanth and cement to produce new composite materials. 48 new samples are produced by varying the percentages of the fly ash, waste ash, cement and tragacanth. The new samples are subjected to some tests to find out their properties such as thermal conductivity, compressive strength, tensile strength and sucking capability of water. It is found that; the thermal conduct...

  6. Coal ash parameters by neutron activation

    International Nuclear Information System (INIS)

    Chrusciel, Edward; Chau, N.D.; Niewodniczanski, J.W.

    1994-01-01

    The coal parameters, ash content and ash slagging index, may be strongly related to the chemical composition of mineral impurities in coal. Based on this assumption the authors have examined the feasibility of neutron activation techniques, both as a laboratory and a well logging method, by recording induced γ-rays in the two energy intervals with the help of a scintillation γ-ray spectrometer. Results from the Upper Silesiab Coal Basin have shown that the method can be used to evaluate the ash content and ash fusion temperature, both in the laboratory and in well logging; the corresponding mean standard deviations being 1.5 wt% and 35 o C; and 3 wt% and 45 o C respectively. (author)

  7. The Ash Wednesday supper a new translation

    CERN Document Server

    Bruno, Giordano

    2018-01-01

    Giordano Bruno's The Ash Wednesday Supper presents a revolutionary cosmology founded on the new Copernican astronomy that Bruno extends to infinite dimensions, filling it with an endless number of planetary systems.

  8. ASH External Web Portal (External Portal) -

    Data.gov (United States)

    Department of Transportation — The ASH External Web Portal is a web-based portal that provides single sign-on functionality, making the web portal a single location from which to be authenticated...

  9. Basic soil benefits from ash utilization

    Energy Technology Data Exchange (ETDEWEB)

    Martens, D.C.; Plank, C.O.

    1970-01-01

    The beneficial effects of fly ash application shown herein are expected to encourage future disposal of the material in agricultural soils. It is foreseen, however, that fly ash disposal in agricultural soils would be unsuccessful if adverse effects on crop production result from its misuse. It seems evident, therefore, that quality control measures will be required to insure proper disposal of the material in agricultural soils. It will be necessary to consider differences in chemical properties of various samples of fly ash and in chemical reactions of samples of fly ash and soils. Differences in tolerances of plants to soluble salt damage and to specific nutrient deficiencies and toxicities will also have to be taken into account. 9 tables.

  10. Volcanic Ash Advisory Database, 1983-2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Volcanic ash is a significant hazard to aviation and can also affect global climate patterns. To ensure safe navigation and monitor possible climatic impact, the...

  11. EFFECT OF PALM EMPTY BUNCH ASH ON TRANSESTERIFICATION OF PALM OIL INTO BIODIESEL

    Directory of Open Access Journals (Sweden)

    Johan Sibarani

    2010-06-01

    Full Text Available Biodiesel conversion from transesterification reaction palm oil with methanol was studied by using an ash of palm empty bunch as a base catalyst. Atomic absorption spectroscopy (AAS and indicator titration analysis were used as tools for characterization of ash sample. Chemical structure of biodiesel was analyzed by GC-MS. The effects of ash sample weight (5, 10, 15, 20 and 25 g immersed in 75 mL methanol and the methanol-palm oil mol ratio (3:1; 6:1; 9:1 and 12:1 toward the conversion of biodiesel were investigated. Biodiesel was prepared by refluxing palm oil and methanol containing ash sample. The reflux was done at room temperature for 2 h. Ester layer was distillated at 74 oC, extracted with aquadest and then dried using Na2SO4 anhydrous. The product was characterized by GC-MS, ASTM D 1298 (specific gravity 60/60 °F, ASTM D 97 (pour point, ASTM D 2500 (cloud point, ASTM D 93 (flash point, ASTM D 445 (kinematics viscosity 40 °C and ASTM D 482 (ash content. The result of GC-MS analysis showed that methyl palmitate is primary content of biodiesel product. A 15 g weight of ash sample gave the maximum biodiesel conversion. By increasing methanol mole quantity, biodiesel conversion increased progressively and maximum at 9:1 methanol-palm oil ratio (84.12 % and decreased on 12:1 ratio (75.58 %. Most of the biodiesel products were similar to those of the diesel physical characters.   Keywords: Biodiesel conversion, transesterification, palm oil, palm empty bunch

  12. Permeability Characteristics of Compacted and Stabilized Clay with Cement, Peat Ash and Silica Sand

    Directory of Open Access Journals (Sweden)

    Seyed Esmaeil Mousavi

    2016-06-01

    Full Text Available The present paper investigates the influence of stabilization with cement, peat ash, and silica sand on permeability coefficient (kv of compacted clay, using a novel approach to stabilize the clay with peat ash as a supplementary material of cement in the compacted and stabilized soil. In order to assess the mentioned influence, test specimens of both untreated and stabilized soil have been tested in the laboratory so that their permeability could be evaluated. Falling head and one dimensional consolidation tests of laboratory permeability were performed on the clay specimens and the chemical compositions of the materials as well as microstructure of the stabilized soil with 18% cement, 2% peat ash, and 5% silica sand were investigated, using X-ray fluorescence and scanning electron microscopy respectively. Results show that for soil stabilization with up to 8% cement content (of the dry weight of the soil, the average value of coefficient of permeability (kv is very close to that of untreated soil, whereas the kv value decreases drastically for 18% cement under identical void ratio conditions. It is further revealed that addition of 18% cement, 2% peat ash, and 5% silica sand had decreased the coefficient of permeability by almost 2.2 folds after 24 h, while about 1.7 folds increase was observed in coefficient of permeability once 13.5% of cement, 1.5% of peat ash, and 20% of silica sand were added. The partial replacement of cement with the 2% peat ash can reduce the consumption of cement for soil stabilization.

  13. Electrodialytic removal of heavy metals from different fly ashes. Influence of heavy metal speciation in the ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2003-01-01

    Electrodialytic Remediation has recently been suggested as a potential method for removal of heavy metals from fly ashes. In this work electrodialytic remediation of three different fly ashes, i.e. two municipal solid waste incinerator (MSWI) fly ashes and one wood combustion fly ash was studied...... in lab scale, and the results were discussed in relation to the expected heavy metal speciation in the ashes. In initial leaching experiments the pH-dependent desorption characteristics of the heavy metals Cd, Pb, Zn and Cu were analogous in the two MSWI ashes, and thus it was expected......-moval efficiencies were observed, especially for Pb and Zn. Cd, the sole heavy metal of environmental concern in the wood ash, was found more tightly bonded in this ash than in the two MSWI ashes. It was suggested that complex Cd-silicates are likely phases in the wood ash whereas more soluble, condensed phases...

  14. Leaching of saltstones containing fly ash

    International Nuclear Information System (INIS)

    Barnes, M.W.; Roy, D.M.; Langton, C.A.

    1985-01-01

    Two types of fly ash were incorporated in saltstones designed for potential encapsulation of Savannah River Plant low level defense waste. These fly ashes have some cementitious properties while at the same time their presence in substitution for cement slows early hydration. Class C fly ash has a high calcium content and is considered cementitious; Class F fly ash has a low calcium content and is not classified as cementitious. Leach tests were performed and physical properties were measured for saltstones containing each class, to see the differences in the effect of the fly ashes. The four waste ions nitrate, nitrite, sodium and sulfate were shown to leach by diffusion. Effective diffusivities were determined for these ions. Data for nitrate, the most important species from the environmental point of view, are shown in Table A. Saltstones made with Class C fly ash have substantially lower leach rates than those made with Class F fly ash. The leach rates, and therefore the square roots of the effective diffusivities, have been found to be proportional to the pore surface area per unit volume (or the ratio of pore volume to pore radius), to the fraction of waste containing solution, and to the inverse of the fraction of calcium in the saltstone. Rates and diffusivities are not proportional to the water to cement ratio, because this number depends on whether the fly ash is counted as cementitious, as in Class C cement, or not cementitious, as in Class F cement. In fact the relatively small amount of calcium in Class F cement contributes to the cementitious properties overall, though not so much as Class C cement. 4 refs., 2 figs., 6 tabs

  15. Assessment of the exposure of islanders to ash from the Soufriere Hills volcano, Montserrat, British West Indies.

    Science.gov (United States)

    Searl, A; Nicholl, A; Baxter, P J

    2002-08-01

    The Soufriere Hills volcano, Montserrat, has been erupting since July 1995 and volcanic ash has fallen on the island throughout most of the eruption. The ash contains substantial quantities of respirable particles and unusually large amounts (15-20%) of the crystalline silica mineral, cristobalite. The purpose of the surveys described here, undertaken between December 1996 and April 2000, was to determine levels of personal exposure of islanders to volcanic ash and cristobalite in order to inform advice on the associated risks to health and the measures required to reduce exposure. Surveys of personal exposure to respirable dust and cristobalite were undertaken using cyclone samplers. In addition, direct reading instruments (DUSTTRAK) were used to monitor ambient air concentrations of PM(10) at fixed sites and also to provide information about exposures to airborne particles associated with selected activities. Environmental concentrations of airborne ash have been greatest in the areas where the most ash has been deposited and during dry weather. Individual exposure to airborne ash was related to occupation, with the highest exposures among gardeners, cleaners, roadworkers, and police at roadside checkpoints. During 1997 many of these individuals were exposed to concentrations of cristobalite that exceeded the ACGIH recommended occupational exposure limit. Since the population became confined to the north of the island in October 1997, even those in relatively dusty occupations have received exposures to cristobalite well below this limit. Most of the 4500 people who have remained on island since the eruption began have not been exposed to sufficiently high concentrations of airborne dust for long enough to be at risk of developing silicosis. However, more than a dozen individuals continued to experience frequent high occupational exposures to volcanic ash, some of whom may have had sufficient exposure to crystalline silica to be at risk of developing mild

  16. Use of wood ash for road stabilisation

    International Nuclear Information System (INIS)

    Lagerkvist, A.; Lind, B.

    2009-01-01

    Due to warmer winters in Sweden, the bearing capacity of forestry roads has become increasingly problematic in recent years. Road stabilization is needed in order to get timber out from the forests. This usually involves the addition of cement to the road body. However, wood ash is a possible substitute for cement because it has similar properties. Using wood ash has the added advantage of saving landfill space. This paper presented an ongoing laboratory study on leaching and mechanical stability, as well as frost-sensitivity using a 30 per cent ash addition to natural soils for reinforcing a forestry road near Timra in central Sweden. The road was being monitored with regard to environmental impact and mechanical properties. The paper discussed the potential of biofuel ashes and the increasing need to reinforce infrastructure due to climate change. The environmental impact from ash use in road constructions was then addressed. It was concluded that the application of ash in road construction would help to strengthen forest roads, make them more resistant to climatic change and render them accessible year-round. 32 refs., 3 tabs., 2 figs.

  17. Utilization of pulverized fuel ash in Malta

    International Nuclear Information System (INIS)

    Camilleri, Josette; Sammut, Michael; Montesin, Franco E.

    2006-01-01

    In Malta all of the waste produced is mixed and deposited at various sites around the island. None of these sites were purpose built, and all of the waste is above groundwater level. The landfills are not engineered and do not contain any measures to collect leachate and gases emanating from the disposal sites. Another waste, which is disposed of in landfills, is pulverized fuel ash (PFA), which is a by-product of coal combustion by the power station. This has been disposed of in landfill, because its use has been precluded due to the radioactivity of the ashes. The aim of this study was to analyze the chemical composition of the pulverized fuel ash and to attempt to utilize it as a cement replacement in normal concrete mixes in the construction industry. The levels of radiation emitted from the ashes were measured by gamma spectrometry. The results of this study revealed that although at early ages cement replacement by PFA resulted in a reduction in compressive strength (P = 0), when compared to the reference concrete at later ages the strengths measured on concrete cores were comparable to the reference concrete (P > 0.05). The utilization of PFA up to 20% cement replacement in concrete did not raise the radioactivity of the concrete. In conclusion, utilization of PFA in the construction industry would be a better way of disposing of the ashes rather than controlling the leachate and any radioactivity emitted by the landfilled ashes

  18. The UZPI ash content monitoring device

    Energy Technology Data Exchange (ETDEWEB)

    Novikov, E.P.; Bezverkhii, E.A.; Mozhaev, L.G.

    1987-07-01

    This paper describes the results of industrial trials (in coal preparation plants) to establish the accuracy of the UZPI device which determines coal ash content using X-ray detection. It is designed to monitor ash content in the 4-40% range in coal with a grain size of 0-100 mm and a coal layer thickness of 50-150 mm (depending on the ash content and grain size). The ash frequently contains oxides, and although variations in magnesium, aluminium, silicon and sulfur oxides have virtually no effect on accuracy of the UZPI, changes in the levels of calcium oxides and particularly iron oxides have a considerable influence on measurement accuracy (caused by changes in their gamma ray scattering cross section values and atomic numbers). The overall sensitivity to ash content in coal varies from 1.6 to 2.4% abs./% while that to iron oxides in ash is 0.4% abs./%. Concludes that this device is suitable for use in coal preparation plants on thin layers of coal, but its efficiency is affected by external influences, e.g. fluctuations in conveyor loading.

  19. Wildland fire ash: future research directions

    Science.gov (United States)

    Bodí, Merche B.; Martins, Deborah A.; Cerdà, Artemi; Balfour, Victoria N.; Santin, Cristina; Doerr, Stefan H.; Pereira, Paulo; Mataix-Solera, Jorge

    2014-05-01

    Ash is a key component of the forest fires affected land (Cerdà, 1998; Bodí et al., 2011; Pereira et al., 2013a). Ash controls the hydrological processes and determines the water repellency (Dlapa et al., 2012) and the infiltration rates (Cerdà and Doerr, 2008;). Moreover, ash is the key factor on runoff initiation and then on the soil erosion. Little is known about the impact of ash in different ecosystems, but during the last decade a substantial increase in the papers that show the role of ash in the Earth and Soil System were published (Bodí et al., 2012; Pereira et al., 2013b).. Ash is being found as the key component of the post-fire pedological, geomorphological and hydrological response after forest fires (Fernández et al., 2012; Martín et al., 2012; Bodí et al., 2013; Guénon et al., 2013; Pereira et al., 2013c). A recent State-of-the-Art review about wildland fire ash (Bodí et al., 2014) compiles the knowledge regarding the production, composition and eco-hydro-geomorphic effects of wildland fire ash. In the present paper we indicate the knowledge gaps detected and suggest topics that need more research effort concerning: i) data collection and analysis techniques: a) To develop standardized sampling techniques that allow cross comparison among sites and avoid inclusion of the underlying soil unless the burned surface soil forms part of the ash layer, b) To develop standardized methods to define and characterize ash, including its color, physical properties such as particle size distribution or density, proportion of pyrogenic C, chemical and biological reactivity and persistence in the environment, c) To validate, calibrate and test measurements collected through remote sensing with on-the-ground measurements. ii) ash production, deposition redistribution and fate: d) To untangle the significance of the effects of maximum temperature reached during combustion versus the duration of heating, e) To understand the production of ash by measuring its

  20. Immersion freezing induced by different kinds of coal fly ash: Comparing particle generation methods and measurement techniques

    Science.gov (United States)

    Grawe, Sarah; Augustin-Bauditz, Stefanie; Clemen, Hans-Christian; Eriksen-Hammer, Stine; Lubitz, Jasmin; Schneider, Johannes; Stratmann, Frank; Wex, Heike

    2017-04-01

    To date, a lot of effort has been put into the identification and characterization of atmospheric ice nucleating particles (INPs), which may influence both weather and climate. The majority of studies focuses on INPs from natural origin such as biological particles or mineral dust particles (Hoose and Möhler 2012, Murray et al. 2012). Combustion ashes, being possible sources of anthropogenic INPs, have rarely been investigated in the past. Ash particles may be emitted into the atmosphere either by the action of wind from ash deposits on the ground (bottom ash), or during the combustion process (fly ash). Two recent studies (Umo et al., 2015; Grawe et al., 2016) identified fly ash from coal combustion as the most efficient of the investigated samples (including also bottom ashes from wood and coal combustion). These results motivate the here presented study in which we investigated the immersion freezing behavior of four coal fly ash samples taken from the filters of different coal-fired power plants in Germany. A combination of two instruments was used to capture the temperature range from 0 °C to the homogeneous freezing limit at around -38 °C. Firstly, the new Leipzig Ice Nucleation Array (LINA) was used, where droplets from an ash-water suspension are pipetted onto a cooled plate. Secondly, we used the Leipzig Aerosol Cloud Interaction Simulator (LACIS; Hartmann et al., 2011), a laminar flow tube in which every droplet contains a single size-segregated ash particle. Here, it was possible to study the effect of different kinds of particle generation, i.e., atomization of an ash-water suspension, and aerosolization of dry ash material. The composition of the ash particles was investigated by means of single particle aerosol mass spectrometry and particles were sampled on filters for environmental scanning electron microscope analysis. Our measurements show that all four fly ash samples feature a similar immersion freezing behavior (ice fractions vary by a

  1. Criticality safety for deactivation of the Rover dry headend process

    International Nuclear Information System (INIS)

    Henrikson, D.J.

    1995-01-01

    The Rover dry headend process combusted Rover graphite fuels in preparation for dissolution and solvent extraction for the recovery of 235 U. At the end of the Rover processing campaign, significant quantities of 235 U were left in the dry system. The Rover Dry Headend Process Deactivation Project goal is to remove the remaining uranium bearing material (UBM) from the dry system and then decontaminate the cells. Criticality safety issues associated with the Rover Deactivation Project have been influenced by project design refinement and schedule acceleration initiatives. The uranium ash composition used for calculations must envelope a wide range of material compositions, and yet result in cost effective final packaging and storage. Innovative thinking must be used to provide a timely safety authorization basis while the project design continues to be refined

  2. Airborne observations of the Eyjafjalla volcano ash cloud over Europe during air space closure in April and May 2010

    Science.gov (United States)

    Schumann, U.; Weinzierl, B.; Reitebuch, O.; Schlager, H.; Minikin, A.; Forster, C.; Baumann, R.; Sailer, T.; Graf, K.; Mannstein, H.; Voigt, C.; Rahm, S.; Simmet, R.; Scheibe, M.; Lichtenstern, M.; Stock, P.; Rüba, H.; Schäuble, D.; Tafferner, A.; Rautenhaus, M.; Gerz, T.; Ziereis, H.; Krautstrunk, M.; Mallaun, C.; Gayet, J.-F.; Lieke, K.; Kandler, K.; Ebert, M.; Weinbruch, S.; Stohl, A.; Gasteiger, J.; Groß, S.; Freudenthaler, V.; Wiegner, M.; Ansmann, A.; Tesche, M.; Olafsson, H.; Sturm, K.

    2011-03-01

    Airborne lidar and in-situ measurements of aerosols and trace gases were performed in volcanic ash plumes over Europe between Southern Germany and Iceland with the Falcon aircraft during the eruption period of the Eyjafjalla volcano between 19 April and 18 May 2010. Flight planning and measurement analyses were supported by a refined Meteosat ash product and trajectory model analysis. The volcanic ash plume was observed with lidar directly over the volcano and up to a distance of 2700 km downwind, and up to 120 h plume ages. Aged ash layers were between a few 100 m to 3 km deep, occurred between 1 and 7 km altitude, and were typically 100 to 300 km wide. Particles collected by impactors had diameters up to 20 μm diameter, with size and age dependent composition. Ash mass concentrations were derived from optical particle spectrometers for a particle density of 2.6 g cm-3 and various values of the refractive index (RI, real part: 1.59; 3 values for the imaginary part: 0, 0.004 and 0.008). The mass concentrations, effective diameters and related optical properties were compared with ground-based lidar observations. Theoretical considerations of particle sedimentation constrain the particle diameters to those obtained for the lower RI values. The ash mass concentration results have an uncertainty of a factor of two. The maximum ash mass concentration encountered during the 17 flights with 34 ash plume penetrations was below 1 mg m-3. The Falcon flew in ash clouds up to about 0.8 mg m-3 for a few minutes and in an ash cloud with approximately 0.2 mg m-3 mean-concentration for about one hour without engine damage. The ash plumes were rather dry and correlated with considerable CO and SO2 increases and O3 decreases. To first order, ash concentration and SO2 mixing ratio in the plumes decreased by a factor of two within less than a day. In fresh plumes, the SO2 and CO concentration increases were correlated with the ash mass concentration. The ash plumes were often

  3. Advanced characterisation of municipal solid waste ashes

    Energy Technology Data Exchange (ETDEWEB)

    Skytte Pedersen, Randi

    2002-12-15

    This report deals with characterisation of Municipal Solid Waste (MSW) ashes from the Danish power plant Maebjergvaerket, Holstebro. MSW has been used as a fuel since the mid 1960's and since then, the MSW incineration plants have experienced operational problems due to deposit formation and corrosion. Inorganic elements tightly or loosely bound in the waste are the main cause of these problems. The tightly bound elements will mainly stay on the grate during combustion, whereas the loosely bound elements are volatilised and recondensed elsewhere in the furnace. Many of the heavy metals form volatile chlorides during the incineration, and the fly ash fraction thus show enrichment in these elements. Presence of chlorides and heavy metals in deposits may cause severe corrosion due to formation of low-melting eutectics. Chlorine gas in the flue gas is also of major concern with respect to corrosion, due to formation of volatile chlorides when chlorine comes in contact with the tube material. Four different ash fractions (bottom ash, super heater ash, economiser ash and fly ash) taken from Maebjergvaerket have been analysed with respect to particle sizes, structures, shapes and composition. The applied methods were scanning electron microscopy (SEM), energy dispersive X-ray analyses (EDX) and mapping, which were used in order to determine sizes, chemical composition and structure of the particles. X-ray powder diffraction (XRD) was used to provide information about crystallography and mineral phases. Chemical analysis was also performed along with a particle size distribution for the fine-grained fractions (economiser and fly ash). The amount of silicates consisting of Ca, Al and Si, were found to decrease through the furnace, whereas the amount of alkali (Na, K) chlorides and heavy metals (Pb, Zn) increased. The bonding in the waste before incineration is the direct cause of this, since silicates are tightly bound and chlorides are loosely bound. There was a

  4. Valorization of MSWI bottom ash for biogas desulfurization: Influence of biogas water content.

    Science.gov (United States)

    Fontseré Obis, Marta; Germain, Patrick; Troesch, Olivier; Spillemaecker, Michel; Benbelkacem, Hassen

    2017-02-01

    In this study an alternative valorization of Municipal Solid Waste Incineration (MSWI) Bottom Ash (BA) for H 2 S elimination from landfill biogas was evaluated. Emphasis was given to the influence of water content in biogas on H 2 S removal efficiency by BA. A small-scale pilot was developed and implemented in a landfill site located in France. A new biogas analyzer was used and allowed real-time continuous measurement of CH 4 , CO 2 , O 2 , H 2 S and H 2 O in raw and treated biogas. The H 2 S removal efficiency of bottom ash was evaluated for different inlet biogas humidities: from 4 to 24g water /m 3 . The biogas water content was found to greatly affect bottom ash efficiency regarding H 2 S removal. With humid inlet biogas the H 2 S removal was almost 3 times higher than with a dry inlet biogas. Best removal capacity obtained was 56gH 2 S/kgdryBA. A humid inlet biogas allows to conserve the bottom ash moisture content for a maximum H 2 S retention. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Prospects for long-term ash survival in the core emerald ash borer mortality zone

    Science.gov (United States)

    Jordan M. Marshall; Andrew J. Storer; Roger Mech; Steven A. Katovich

    2011-01-01

    Attacking all North American ash species (Fraxinus spp.), emerald ash borer (EAB) (Agrilus planipennis Fairmaire) has caused significant mortality within its introduced range. For other forest pests, host bark plays an important role in infestation density and oviposition behavior. The objectives of this study were to (1) locate...

  6. Monitoring ash (Fraxinus spp.) decline and emerald ash borer (Agrilus planipennis) symptoms in infested areas

    Science.gov (United States)

    Kathleen S. Knight; Britton P. Flash; Rachel H. Kappler; Joel A. Throckmorton; Bernadette Grafton; Charles E. Flower

    2014-01-01

    Emerald ash borer (A. planipennis) (EAB) has had a devastating effect on ash (Fraxinus) species since its introduction to North America and has resulted in altered ecological processes across the area of infestation. Monitoring is an important tool for understanding and managing the impact of this threat, and the use of common...

  7. Effect of ash components on the ignition and burnout of high ash coals

    Energy Technology Data Exchange (ETDEWEB)

    Feng, B.; Yan, R.; Zheng, C.G. [Huazhong University of Science and Technology, Wuhan (China). National Laboratory of Coal Combustion

    1998-11-01

    The effect of the ash components on the ignition and burnout of four Chinese high ash coals were studied by thermogravimetric analysis. To investigate the influence of the ash components, comparative experiments were carried out with original, deashed and impregnated coals. Eleven types of ash components, such as SiO{sub 2}, CaCO{sub 3}, MgO, Na{sub 2}CO{sub 3}, K{sub 2}CO{sub 3}, Al{sub 2}O{sub 3}, TiO{sub 2}, Fe{sub 2}O{sub 3}, FeS{sub 2}, NH{sub 4}Fe(SO{sub 4}){sub 2}{center_dot}12H{sub 2}O and FeSO{sub 4},(NH{sub 4}){center_dot}6H{sub 2}O were used in the present study. It was found that most of the ash components have negative effects. The strong influence of some ash components suggests that the combustion characteristics of high ash coal may be determined by the ash composition. 5 refs., 2 figs., 2 tabs.

  8. Breeding strategies for the development of emerald ash borer - resistant North American ash

    Science.gov (United States)

    Jennifer L. Koch; David W. Carey; Kathleen S. Knight; Therese Poland; Daniel A. Herms; Mary E. Mason

    2012-01-01

    The emerald ash borer (Agrilus plannipennis; EAB) is a phloem-feeding beetle that is endemic to Asia. It was discovered in North America in 2002, found almost simultaneously near Detroit, Michigan and Windsor, Ontario, Canada. Adult beetles feed on ash (Fraxinus spp.) foliage, but larval feeding on phloem, cambium, and...

  9. Fly ash dynamics in soil-water systems

    International Nuclear Information System (INIS)

    Sharma, S.; Fulekar, M.H.; Jayalakshmi, C.P.

    1989-01-01

    Studies regarding the effluents and coal ashes (or fly ash) resulting from coal burning are numerous, but their disposal and interactions with the soil and water systems and their detailed environmental impact assessment with concrete status reports on a global scale are scanty. Fly ash dynamics in soil and water systems are reviewed. After detailing the physical composition of fly ash, physicochemical changes in soil properties due to fly ash amendment are summarized. Areas covered include texture and bulk density, moisture retention, change in chemical equilibria, and effects of fly ash on soil microorganisms. Plant growth in amended soils is discussed, as well as plant uptake and accumulation of trace elements. In order to analyze the effect of fly ash on the physicochemical properties of water, several factors must be considered, including surface morphology of fly ash, pH of the ash sluice water, pH adjustments, leachability and solubility, and suspended ash and settling. The dynamics of fly ash in water systems is important due to pollution of groundwater resources from toxic components such as trace metals. Other factors summarized are bioaccumulation and biomagnification, human health effects of contaminants, and the impact of radionuclides in fly ash. Future research needs should focus on reduction of the environmental impact of fly ash and increasing utilization of fly ash as a soil amendment. 110 refs., 2 figs., 10 tabs

  10. AL(0) in municipal waste incinerator ash

    Science.gov (United States)

    Stipp, S. L.; Ronsbo, J. G.; Zunic, T. B.; Christensen, T. H.

    2003-04-01

    Disposal of municipal waste is a challenge to society. Waste volume is substantially decreased by incineration but residual ash usually contains a number of toxic components which must be immobilised to insure environmental protection. One element, chromium, is mobile and toxic in its oxidised state as Cr(VI) but it can be reduced to Cr(III) and immobilised. Reduction can be promoted by ash treatment with Fe(0) or Fe(II), but recent evidence shows that at least some Cr(VI) is reduced spontaneously in the ash. Aspects of ash behaviour suggest metallic aluminium as the reducing agent, but no direct evidence of Al(0) has been found until now. We examined filter ash from an energy-producing, municipal-waste incinerator (Vest-forbrænding) near Copenhagen. X-ray diffraction (XRD) identified expected salts of Na, K and Ca such as halite, sylvite, calcite, anhydrite and gypsum as well as quartz, feldspar and some hematite. Wave-dispersive electron microprobe produced elemen-tal maps of the ash; Al-rich areas were analysed quantitatively by comparison with standards. We identified metallic Al particles, averaging 50 to 100 micrometers in di-ameter, often with a fractured, glassy border of aluminum oxide. The particles were porous, explaining fast Cr(VI) reduction and they contained thin exsolution lamellae of Al-alloys of Pb and Cu or Mn, Fe and Ag, which provide clues of the Al(0) origin in the waste. Sometimes Al(0) occurred inside glassy globes of Al2O3. Time-of-flight secondary ion mass spectroscopy (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS) proved that surface Al concentrations on ash particles were below detection, confirming reactivity of the Al(0) bulk. The persistence of reduced Al through the highly oxidising combustion procedure comes as a surprise and is a benefit in the immobilisation of Cr(VI) from municipal-waste incineration residues.

  11. Bioleaching of trace metals from coal ash using local isolate from coal ash ponds

    Directory of Open Access Journals (Sweden)

    Pangayao Denvert

    2018-01-01

    Full Text Available Bioleaching of chromium, copper, manganese and zinc from coal ash were investigated using isolates from coal ash ponds particularly Psuedomonas spp. Six (6 different coal ash ponds were examined however, after initial screening Psuedomonas spp. were only present in three (3 coal ash ponds. Among the three coal ash ponds, results showed that eight (8 putative Pseudomonas spp. isolates were present that were identified using the Polymerase Chain Reaction (PCR. Using the eight putative Pseudomonas spp. for bioleaching at optimum conditions and 15 days, the pH value ranges from 8.26 to 8.84 which was basic in nature. Moreover, the maximum metal leached were 8.04% Cr, 12.05% Cu, 4.34% Mn and 10.63% Zn.

  12. Ash fusion temperatures and the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.K.; Wall, T.F.; Creelman, R.A.; Gupta, R.P. [University of Newcastle, Newcastle, NSW (Australia). CRC for Black Coal Utilisation

    1998-07-01

    A mechanistic study is detailed in which coal ash is heated with its shrinkage measured continuously up to a temperature of 1600{degree}C. The temperature corresponding to the rapid rate of shrinkage correspond to the formation of eutectics identified on phase diagrams. Samples were therefore heated to these temperatures, cooled rapidly and examined using a scanning electron microscope (SEM) to identify the associated chemical and physical changes. The progressive changes in the range of chemical composition (from SEM), the extent of undissolved ash particles and porosity were then quantified and related to homogenisation, viscosity and ash fusion mechanisms. Alternate ash fusion temperatures based on different levels of shrinkage have also been suggested to characterise the ash deposition tendency of the coals. 13 refs., 9 figs.

  13. Dry Mouth (Xerostomia)

    Science.gov (United States)

    ... Finding Dental Care Home Health Info Health Topics Dry Mouth Saliva, or spit, is made by the salivary ... help keep teeth strong and fight tooth decay. Dry mouth, also called xerostomia (ZEER-oh-STOH-mee-ah), ...

  14. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Dry Eye Symptoms Related Ask an Ophthalmologist Answers Can a six-month dissolvable punctal plug be removed ... my eyes dry after LASIK? Jun 19, 2016 Can I be tested whether I close my eyes ...

  15. Utilization of ashes as construction materials in landfills; Askanvaendning i deponier

    Energy Technology Data Exchange (ETDEWEB)

    Tham, Gustav [Telge AB, Soedertaelje (Sweden); Ifwer, Karin [AaF-Process AB, Stockholm (Sweden)

    2006-03-15

    Large amounts of material will be needed to cover landfill sites in Sweden and other EU states over the next ten years. It is estimated that more than one hundred million tons of material will be required in Sweden alone in order to comply with the EU Landfill Directive (1999/31/EC). Suitable natural materials to be used in landfill cover constructions are not available on site. This report summarises the present use of secondary construction material in waste management with a focus on incineration ash. Information from eleven landfill sites has been compiled and includes the practical experience of using ash as the primary material in landfill cover. Other applications of using ash on landfill sites are also discussed. According to Swedish law, a complete cover of a landfill site consists of five different layers, each having its own specific function. The permeability of the total cover should then satisfy the permeability requirements of 50 litres per square meter and year for non-hazardous waste landfill sites and 5 litres per square meter and year for those with hazardous waste. The main purpose of this report is to describe how ash is used in the different layers and discuss the advantages or disadvantages of the techniques applied. Various landfill sites have submitted information ranging from small test areas on a pilot scale to full scale application of techniques on several hectares. Each project is part of the general Vaermeforsk research program for 2003-2005, Environmentally proper use of ash. The overall results show that incineration ash is a suitable material for use in liner constructions, either alone, or mixed with sewage sludge. Data from water percolating below the liner has indicated that the liners can meet permeability requirements. Special techniques for applying the various layers have been described. It is important to have materials readily available for an area, in order to avoid long period of exposure to dry or wet weather. Some

  16. Speciation of Zinc in ash investigated by X-ray absorption spectroscopy; Zinks foerekomstformer i aska studerade med en roentgenabsorptionsspektrometrisk metod

    Energy Technology Data Exchange (ETDEWEB)

    Steenari, Britt-Marie; Noren, Katarina

    2008-06-15

    Direct identification of trace metal compounds in solid materials is difficult to achieve due to the detection limits of available analytical methods. Although zinc is the most abundant trace metal in combustion residues, the number of publications dealing with its direct speciation is small. Struis and co-workers have published an investigation where they used Extended X-ray Absorption Fine Structure spectroscopy (EXAFS) measurements to identify zinc compounds in municipal solid waste incineration fly ash. The EXAFS technique has been used more often for speciation of Zn in contaminated soil. EXAFS data for farm soil samples showed that zinc was most commonly sequestered in layer silicates, but soil particles containing zinc sulphide, zinc chromite and zinc phosphate were also found. Generally, published results show that zinc after being mobilised in a soil, has a clear tendency to be sequestered in silicates, as sulphides or, if there is phosphate available, as phosphate. The aim of the work presented in this work was to use the EXAFS method to show how zinc in chemically bound in ash from woody fuels and from municipal solid waste (MSW). The results can be used for evaluations of the possible toxicity of ash and in predictions of the leaching of zinc from ash. The investigation comprised dry ashes from two fluidised bed combustors fired with forestry litter, bark and other wood fuels, moistened and aged wood ashes and dry ashes from three MSW incinerators: one fluidised bed combustor and two stoker fired combustors. The spectroscopic measurements were carried out at the beam line I811 in the Swedish national synchrotron facility Maxlab at Lund University. The results showed that the lowest concentration of Zn in ash for which it is possible to get any information about the nearest neighbour atoms around zinc is about 500 mg Zn per kg dry ash. If the concentration is higher than 1000 mg/ kg it is possible to obtain information, not only about the nearest

  17. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ...

  18. Effects of a layer of vegetative ash layer on wettable and water repellent soil hydrology

    Science.gov (United States)

    Bodí, Merche B.; Doerr, Stefan H.; Cerdà, Artemi; Mataix-Solera, Jorge

    2010-05-01

    Following a wildfire, a layer of vegetative ash often covers the ground until it is dissolved or redistributed by wind and water erosion. Much of the existing literature suggests that the ash layer temporally reduces infiltration by clogging soil pores or by forming a surface crust (Mallik et al., 1984; Onda et al., 2008). However, an increasing number of field-based studies have found that, at least in the short term, ash increases infiltration by storing rainfall and protecting the underlying soil from sealing (Cerdà and Doerr, 2008; Woods and Balfour, 2008). On the other hand, after a fire the soil may have produced, enhanced or reduced its water repellency (Doerr et al., 2000). Very few studies have been taken into account the interaction of the ash and the repellent soil. The layer of ash may have similar role as a litter layer in delaying runoff and reducing erosion by storing water. In order to examine this interaction, it was been made a series of experiments using a laboratory rainfall simulation. It has been assessed the effects of an ash layer i) on a wettable and water repellent soil (WDPT > 7200s), ii) with different ash thicknesses (bare soil and 5 mm, 15 mm and 30 mm of ash), iii) preceding and following the first rain after a fire when the ground is still wetted and after being partially dried. Three replicates were done, being a total of 40 simulations. The ash used was collected from a Wildfire in Teruel (Spain) during summer of 2009. The simulations were conducted in metal boxes of 30x30 cm and filled with 3 cm of soil. The slope of the box was set at 10° (17%) and the intensity applied was 78-84 mm h-1during 40 minutes. The splash detachment was determined also using four splash cups. Overland flow and subsurface drainage was collected at 1-minute intervals and the former stored every 5 min to allow determination of sediment concentrations, yield and erosion rates. Each sample was examined at the end in terms of water repellency, infiltration

  19. Plant and animal species composition and heavy metal content in fly ash ecosystems

    International Nuclear Information System (INIS)

    Brieger, G.; Wells, J.R.; Hunter, R.D.

    1992-01-01

    Plant and animal species present on a coal fly ash slurry pond site and a dry deposit site were surveyed and sampled during a two-day period in October. Elemental analyses were determined for most of the species encountered. A total of 48 plant species were observed on the two sites, with 35 species on the wet site, and 20 on the dry site. Eighteen terrestrial and 7 aquatic animal species were found on the wet site, exclusive of vertebrates which were not studied with the exception of a carp (Cyprinus carpio). Eleven terrestrial invertebrate and one aquatic species were observed on the dry site. Neutron activation analysis was carried out for: Se, Hg, Cr, Ni, Zn, Co, Sb, Cd, and As. Using literature values for phytotoxicity, it is concluded that, in general, plants did not accumulate toxic levels of metals. Only one plant (Impatiens biflora Willd.) showed a significant level of Cd. Of 20 plants analyzed on the wet site, 10 had excessive Se concentrations (>5 ppm); on the dry site 6 out of 18 had high Se values. In animals (Gryllus sp.; Melanoplus sp.; Trachelipus sp; Lumbricus terrestris; Physa integra; Cyprinus carpio) the trace metal concentration was generally in between that of control animals and that of the fly ash itself. One exception included Zn, which, although the most variable element examined, was concentrated in all the terrestrial animals to levels higher than in fly ash. Crickets are the most consistent bioconcentrators with Cr, Se, and Zn at higher levels than for control animals. All animals species studied accumulated Se compared to controls. 48 refs., 6 tabs

  20. Grouting of fly ash in sanitary landfills; Injektering av flygaska i hushaallsavfallsdeponi

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, Karin; Berg, Magnus [AaF-Energi och Miljoe AB, Stockhom (Sweden); Andreas, Lale; Lagerkvist, Anders [Luleaa Univ. of Technology (Sweden); Jannes, Sara; Tham, Gustav [Telge Aatervinning AB, Soedertaelje (Sweden); Sjoeblom, Rolf [Tekedo AB, Nykoeping (Sweden)

    2003-10-01

    required. Grouting of about a thousand tons of ash in a landfill is probably needed to achieve noticeable affects. The economic evaluation in this study shows that it is profitable/beneficial to use relatively large grouting equipments for grouting in landfills. The cost will be approximately 800 SEK/tons of dry ash if the equipment has a capacity of 10 tons per hour (including drilling and operating crew). However, this cost could probable be reduced to the same level as today's landfill tax in Sweden (370 SEK/ton) if the drilling and grouting is performed in one step and the work is done in two shifts. Another advantage with large equipment is that the grouting could be performed continuously in a process where drilling of the grouting holes and grouting is done at the same time. Equipment with a capacity of 100-200 liters per minute and a mixing tank for at least 500 kg material is recommended for grouting in landfill areas. The pump should have a maximal pressure of 20-30 bar to open up fractures in the waste during the start of the grouting work.

  1. Drying Shrinkage of Mortar Incorporating High Volume Oil Palm Biomass Waste

    Science.gov (United States)

    Shukor Lim, Nor Hasanah Abdul; Samadi, Mostafa; Rahman Mohd. Sam, Abdul; Khalid, Nur Hafizah Abd; Nabilah Sarbini, Noor; Farhayu Ariffin, Nur; Warid Hussin, Mohd; Ismail, Mohammed A.

    2018-03-01

    This paper studies the drying shrinkage of mortar incorporating oil palm biomass waste including Palm Oil Fuel Ash, Oil Palm Kernel Shell and Oil Palm Fibre. Nano size of palm oil fuel ash was used up to 80 % as cement replacement by weight. The ash has been treated to improve the physical and chemical properties of mortar. The mass ratio of sand to blended ashes was 3:1. The test was carried out using 25 × 25 × 160 mm prism for drying shrinkage tests and 70 × 70 ×70 mm for compressive strength test. The results show that the shrinkage value of biomass mortar is reduced by 31% compared with OPC mortar thus, showing better performance in restraining deformation of the mortar while the compressive strength increased by 24% compared with OPC mortar at later age. The study gives a better understanding of how the biomass waste affect on mortar compressive strength and drying shrinkage behaviour. Overall, the oil palm biomass waste can be used to produce a better performance mortar at later age in terms of compressive strength and drying shrinkage.

  2. Apparent digestibility coefficient of duckweed (Lemna minor), fresh and dry for Nile tilapia (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    El-Shafai, S.A.A.M.; El-Gohary, F.; Verreth, J.A.J.; Schrama, J.W.; Gijzen, H.J.

    2004-01-01

    Dry matter (DMD), protein (PD), ash (AD), fat (FD), gross energy (ED) and phosphorus (PhD) digestibility coefficients were determined for five different iso-N fish diets fed to Nile tilapia (Oreochromis niloticus). The control diet contained fishmeal (35%), corn (29%), wheat (20%), wheat bran (10%),

  3. An analysis of impact on the environmental pollution under accident conditions due to the disposal of ashes from the Nikola Tesla B thermal power plant

    International Nuclear Information System (INIS)

    Milovanovic, D.; Zlvkovic, Z.

    1996-01-01

    The ash disposal area of Nikola Tesla B TPP is presenting considerable potential source of environmental pollution. Due to its vast area, that is for an effective plot of about 400 ha, under unfavorable meteorological conditions the emerging of ash cloud spreading over the surrounding area at distances of over 15 km could be produced. This paper deals with accident conditions at ash disposal area which, after stopping of sprinkling operation or in case of an inadequate sequence of ash tapping, when larger portions of disposal area are dried, turn into area of air polluting sources. Computations of particle dispersions under such conditions have been performed for different meteorological conditions and the results are represented as space distribution of particle deposition on the soil and their concentration in the air. (author). 5 figs., 4 refs

  4. Effects of the addition of oil shale ash and coal ash on physic-chemical properties of CPJ45 cement

    Directory of Open Access Journals (Sweden)

    Nabih K.

    2014-04-01

    Full Text Available We focused our research on recycling industrial wastes, fly ash (F.A, bottom ash (B.A and oil shale ash (S.A in cement production. The study concerns physico-chemical characterization of these products and the influence of their addition on the mechanical proprieties of the CPJ45 cement. XRF allowed us to rank the three additives used according to their contents on major oxides. Coal ashes belong to the class F, and thus possess poozzolanic properties and oil shale ash belongs to the class C and possesses hydraulic and poozolanic properties. The crystalline phases constituting each ash were analysed by XRD. We observe in bottom ash the presence of quartz and mullite. The same crystals are found in fly ash with hematite and magnetite. Oil shale ash is composed of quartz, anhydrite, gehlenite, wollastonite and periclase. The microstructures of fly ash and bottom ash were studied using SEM. The bottom ash was composed respectively of fine particles that are generally irregularly shaped, their dimensions are between 5 and 28μm and of big particles(300 μm. The EDX analysis coupled with an electronic microscope provided some information about the major elements that constitute our samples. The dehydrations of anhydrous and three days hydrated cement were examined by DSC. For hydrated cements we noticed endothermic peaks related to the dehydration of CSH, CH and decomposition of carbonates. The study of the mechanical properties of CPJ45 cement by adding different proportions of fly ash, bottom ash and oil shale ash helped clarifying the percentage of ash that leaded to improve the 28 days mechanical strength. The results show that the cements studied have their maximum mechanical resistance with the addition at 7% of fly ash or 10% of oil shale ash.

  5. Interspecific proteomic comparisons reveal ash phloem genes potentially involved in constitutive resistance to the emerald ash borer.

    Science.gov (United States)

    Whitehill, Justin G A; Popova-Butler, Alexandra; Green-Church, Kari B; Koch, Jennifer L; Herms, Daniel A; Bonello, Pierluigi

    2011-01-01

    The emerald ash borer (Agrilus planipennis) is an invasive wood-boring beetle that has killed millions of ash trees since its accidental introduction to North America. All North American ash species (Fraxinus spp.) that emerald ash borer has encountered so far are susceptible, while an Asian species, Manchurian ash (F. mandshurica), which shares an evolutionary history with emerald ash borer, is resistant. Phylogenetic evidence places North American black ash (F. nigra) and Manchurian ash in the same clade and section, yet black ash is highly susceptible to the emerald ash borer. This contrast provides an opportunity to compare the genetic traits of the two species and identify those with a potential role in defense/resistance. We used Difference Gel Electrophoresis (DIGE) to compare the phloem proteomes of resistant Manchurian to susceptible black, green, and white ash. Differentially expressed proteins associated with the resistant Manchurian ash when compared to the susceptible ash species were identified using nano-LC-MS/MS and putative identities assigned. Proteomic differences were strongly associated with the phylogenetic relationships among the four species. Proteins identified in Manchurian ash potentially associated with its resistance to emerald ash borer include a PR-10 protein, an aspartic protease, a phenylcoumaran benzylic ether reductase (PCBER), and a thylakoid-bound ascorbate peroxidase. Discovery of resistance-related proteins in Asian species will inform approaches in which resistance genes can be introgressed into North American ash species. The generation of resistant North American ash genotypes can be used in forest ecosystem restoration and urban plantings following the wake of the emerald ash borer invasion.

  6. Ge extraction from gasification fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Oriol Font; Xavier Querol; Angel Lopez-Soler; Jose M. Chimenos; Ana I. Fernandez; Silvia Burgos; Francisco Garcia Pena [Institute of Earth Sciences ' Jaume Almera' , Barcelona (Spain)

    2005-08-01

    Water-soluble germanium species (GeS{sub 2}, GeS and hexagonal-GeO{sub 2}) are generated during coal gasification and retained in fly ash. This fact together with the high market value of this element and the relatively high contents in the fly ashes of the Puertollano Integrated Gasification in Combined Cycle (IGCC) plant directed our research towards the development of an extraction process for this element. Major objectives of this research was to find a low cost and environmentally suitable process. Several water based extraction tests were carried out using different Puertollano IGCC fly ash samples, under different temperatures, water/fly ash ratios, and extraction times. High Ge extraction yields (up to 84%) were obtained at room temperature (25{sup o}C) but also high proportions of other trace elements (impurities) were simultaneously extracted. Increasing the extraction temperature to 50, 90 and 150{sup o}C, Ge extraction yields were kept at similar levels, while reducing the content of impurities, the water/fly ash ratio and extraction time. The experimental data point out the influence of chloride, calcium and sulphide dissolutions on the Ge extraction. 16 refs., 9 figs., 6 tabs.

  7. National volcanic ash operations plan for aviation

    Science.gov (United States)

    ,; ,

    2007-01-01

    The National Aviation Weather Program Strategic Plan (1997) and the National Aviation Weather Initiatives (1999) both identified volcanic ash as a high-priority informational need to aviation services. The risk to aviation from airborne volcanic ash is known and includes degraded engine performance (including flameout), loss of visibility, failure of critical navigational and operational instruments, and, in the worse case, loss of life. The immediate costs for aircraft encountering a dense plume are potentially major—damages up to $80 million have occurred to a single aircraft. Aircraft encountering less dense volcanic ash clouds can incur longer-term costs due to increased maintenance of engines and external surfaces. The overall goal, as stated in the Initiatives, is to eliminate encounters with ash that could degrade the in-flight safety of aircrews and passengers and cause damage to the aircraft. This goal can be accomplished by improving the ability to detect, track, and forecast hazardous ash clouds and to provide adequate warnings to the aviation community on the present and future location of the cloud. To reach this goal, the National Aviation Weather Program established three objectives: (1) prevention of accidental encounters with hazardous clouds; (2) reduction of air traffic delays, diversions, or evasive actions when hazardous clouds are present; and (3) the development of a single, worldwide standard for exchange of information on airborne hazardous materials. To that end, over the last several years, based on numerous documents (including an OFCMsponsored comprehensive study on aviation training and an update of Aviation Weather Programs/Projects), user forums, and two International Conferences on Volcanic Ash and Aviation Safety (1992 and 2004), the Working Group for Volcanic Ash (WG/VA), under the OFCM-sponsored Committee for Aviation Services and Research, developed the National Volcanic Ash Operations Plan for Aviation and Support of the

  8. Durability of conventional concretes containing black rice husk ash.

    Science.gov (United States)

    Chatveera, B; Lertwattanaruk, P

    2011-01-01

    In this study, black rice husk ash (BRHA) from a rice mill in Thailand was ground and used as a partial cement replacement. The durability of conventional concretes with high water-binder ratios was investigated including drying shrinkage, autogenous shrinkage, depth of carbonation, and weight loss of concretes exposed to hydrochloric (HCl) and sulfuric (H(2)SO(4)) acid attacks. Two different replacement percentages of cement by BRHA, 20% and 40%, and three different water-binder ratios (0.6, 0.7 and 0.8) were used. The ratios of paste volume to void content of the compacted aggregate (γ) were 1.2, 1.4, and 1.6. As a result, when increasing the percentage replacement of BRHA, the drying shrinkage and depth of carbonation reaction of concretes increased. However, the BRHA provides a positive effect on the autogenous shrinkage and weight loss of concretes exposed to hydrochloric and sulfuric acid attacks. In addition, the resistance to acid attack was directly varied with the (SiO(2) + Al(2)O(3) + Fe(2)O(3))/CaO ratio. Results show that ground BRHA can be applied as a pozzolanic material and also improve the durability of concrete. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Dry and Semi-Dry Tropical Cyclones

    Science.gov (United States)

    Cronin, T.; Chavas, D. R.

    2017-12-01

    Our understanding of dynamics in our real moist atmosphere is strongly informed by idealized dry models. It is widely believed that tropical cyclones (TCs) are an intrinsically moist phenomenon - relying fundamentally on evaporation and latent heat release - yet recent numerical modeling work has found formation of dry axisymmetric tropical cyclones from a state of dry radiative-convective equilibrium. What can such "dry hurricanes" teach us about intensity, structure, and size of real moist tropical cyclones in nature? Are dry TCs even stable in 3D? What about surfaces that are nearly dry but have some latent heat flux - can they also support TCs? To address these questions, we use the SAM cloud-system resolving model to simulate radiative-convective equilibrium on a rapidly rotating f-plane, subject to constant tropospheric radiative cooling. We use a homogeneous surface with fixed temperature and with surface saturation vapor pressure scaled by a factor 0-1 relative to that over pure water - allowing for continuous variation between moist and dry limits. We also explore cases with surface enthalpy fluxes that are uniform in space and time, where partitioning between latent and sensible heat fluxes is specified directly. We find that a completely moist surface yields a TC-world where multiple vortices form spontaneously and persist for tens of days. A completely dry surface can also yield a parallel dry TC-world with many vortices that are even more stable and persistent. Spontaneous cyclogenesis, however, is impeded for a range of low to intermediate surface wetness values, and by the combination of large rotation rates and a dry surface. We discuss whether these constraints on spontaneous cyclogenesis might arise from: 1) rain evaporation in the subcloud layer limiting the range of viable surface wetness values, and 2) a natural convective Rossby number limiting the range of viable rotation rates. Finally, we discuss simulations with uniform surface enthalpy

  10. Thermal treatment of ashes[Fly Ash from Municipal Waste Incineration]; Termisk rening av askor

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, Karin; Berg, Magnus; Bjurstroem, Henrik [AaF-Energi och Miljoe AB, Stockholm (Sweden); Nordin, Anders [Umeaa Univ. (Sweden). Dept. of Applied Physics and Electronics

    2003-04-01

    In this project descriptions of different processes for thermal treatment of ashes have been compiled. A technical and economic evaluation of the processes has been done to identify possibilities and problems. The focus in the project lays on treatment of fly ash from municipal waste incineration but the processes can also be used to treat other ashes. When the ash is heated in the thermal treatment reactor, with or without additives, the material is sintered or vitrified and at the same time volatile substances (Zn, Pb, Cd, Hg etc.) are separated. In general the separation is more effective in processes with reducing conditions compared to oxidizing conditions. Oxidizing processes have both worse separation capacity and require more energy. The oxidizing processes are mainly used to stabilize the ash through vitrification and they are in some cases developed for management of municipal sewage sludge and bottom ash. However, these processes are often not as complex as for example an electric arc melting furnace with reducing conditions. The research today aim to develop more effective electrical melting systems with reducing conditions such as plasma melting furnaces, electric resistance melting furnaces and low frequency induction furnaces. A central question in the evaluation of different thermal treatment processes for ash is how the residues from the treatment can be used. It is not certain that the vitrified material is stable enough to get a high economic value, but it can probably be used as construction material. How the remaining metals in the ash are bound is very important in a long-time perspective. Further studies with leaching tests are necessary to clarify this issue. The heavy metal concentrate from the processes contains impurities, such as chlorine, which makes it unprofitable to obtain the metals. Instead the heavy metal concentrate has to be land filled. However, the amount of material for land filling will be much smaller if only the heavy

  11. Regular Recycling of Wood Ash to Prevent Waste Production (RecAsh). Technical Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Lars E-mail: lars.t.andersson@skogsstyreslen.se

    2007-03-15

    At present, the extraction of harvest residues is predicted to increase in Sweden and Finland. As an effect of the intensified harvesting, the export of nutrients and acid buffering substances from the growth site is also increased. Wood ash could be used to compensate forest soils for such losses. Most wood fuel ash is today often deposited in landfills. If the wood ash is recycled, wood energy is produced without any significant waste production. Ash recycling would therefore contribute to decreasing the production of waste, and to maintaining the chemical quality of forest waters and biological productivity of forest soils in the long term. The project has developed, analysed and demonstrated two regular ash-recycling systems. It has also distributed knowledge gathered about motives for ash recycling as well as technical and administrative solutions through a range of media (handbooks, workshops, field demonstrations, reports, web page and information videos). Hopefully, the project will contribute to decreasing waste problems related to bio-energy production in the EU at large. The project has been organised as a separate structure at the beneficiary and divided in four geographically defined subprojects, one in Finland and three in Sweden (Central Sweden, Northern Sweden, and South-western Sweden). The work in each subproject has been lead by a subproject leader. Each subproject has organised a regional reference group. A project steering committee has been established consisting of senior officials from all concerned partners. The project had nine main tasks with the following main expected deliverables and output: 1. Development of two complete full-scale ash-recycling systems; 2. Production of handbooks of the ash recycling system; 3. Ash classification study to support national actions for recommendations; 4. Organise regional demonstrations of various technical options for ash treatment and spreading; 5. Organise national seminars and demonstrations of

  12. Quality characteristics of Greek fly ashes and potential uses

    Energy Technology Data Exchange (ETDEWEB)

    Skodras, G.; Grammelis, P.; Kakaras, E. [Institute for Solid Fuels Technology and Applications, Ptolemais (Greece); Karangelos, D.; Anagnostakis, M.; Hinis, E. [Nuclear Engineering Section, Mechanical Engineering Department, National Technical University of Athens, Athens (Greece)

    2007-01-15

    The main characteristics of fly ash from Greek coal-fired boilers are presented in this paper in relation to its exploitation potential. Both fuel and fly ash samples were collected and analyzed according to the ASTM Standards. Apart from the typical analyses (proximate, ultimate, ash analysis and calorific value), an ICP-AES spectrometer was used for the analysis of heavy metals in the ash. Experimental measurements in order to determine the radioactivity content of raw fuel and the fly ash were carried out as well. A representative fly ash sample from Ptolemais power plant was evaluated and tested as filler in Self-Compacting Concrete (SCC). Ashes from the Greek brown coal are classified in type C, most of the fly ash being produced in Ptolemais of Northern Greece, while the rest in Megalopolis. Ptolemais fly ash is rich in calcium compounds, while Megalopolis fly ash contains more pyrite. Increased heavy metal concentrations are observed in the fly ash samples of Greek coal. Greek fly ash appears to have not only pozzolanic but also hydraulic behaviour. Furthermore, Greek fly ash, depending on its origin, may have relatively high natural radioactivity content, reaching in the case of Megalopolis fly ash 1 kBq kg{sup -1} of {sup 226}Ra. The laboratory results showed that fly ashes can be a competitive substitute to conventional limestone filler material in SCC. Fly ash is mostly used in Greece in cement industry replacing cement clinker and aiming to the production of special types of Portland cements. However, a more aggressive utilisation strategy should be developed, since low quantities of the total produced fly ash are currently further utilised. (author)

  13. Dry vacuum pumps

    International Nuclear Information System (INIS)

    Sibuet, R

    2008-01-01

    For decades and for ultimate pressure below 1 mbar, oil-sealed Rotary Vane Pumps have been the most popular solution for a wide range of vacuum applications. In the late 80ies, Semiconductor Industry has initiated the development of the first dry roughing pumps. Today SC applications are only using dry pumps and dry pumping packages. Since that time, pumps manufacturers have developed dry vacuum pumps technologies in order to make them attractive for other applications. The trend to replace lubricated pumps by dry pumps is now spreading over many other market segments. For the Semiconductor Industry, it has been quite easy to understand the benefits of dry pumps, in terms of Cost of Ownership, process contamination and up-time. In this paper, Technology of Dry pumps, its application in R and D/industries, merits over conventional pumps and future growth scope will be discussed

  14. Wear behavior of Al-7%Si-0.3%Mg/melon shell ash particulate composites.

    Science.gov (United States)

    Abdulwahab, M; Dodo, R M; Suleiman, I Y; Gebi, A I; Umar, I

    2017-08-01

    The present study examined wear characteristics of A356/melon shell ash particulate composites. Dry-sliding the stainless steel ball against specimen disc revealed the abrasive wear behavior of the composites under loads of 2 and 5N. The composite showed lower wear rate of 2.182 × 10 -4 mm 3 /Nm at 20 wt% reinforced material under load of 5N. Results showed that wear rate decreased significantly with increasing weight percentage of melon shell ash particles. Microstructural analyses of worn surfaces of the composites reveal evidence of plastic deformation of matrix phase. The wear resistance of A356 increased considerably with percentage reinforcement. In other words, the abrasive mass loss decreased with increasing percentage of reinforcement addition at the both applied loads. The control sample suffered a highest mass loss at 5 N applied load.

  15. Synthesis and characterization of zeolite material from coal ashes modified by surfactant

    International Nuclear Information System (INIS)

    Fungaro, D.A.; Borrely, S.I.

    2010-01-01

    Coal ash was used as starting material for zeolite synthesis by means of hydrothermal treatment. The surfactant-modified zeolite (SMZ) was prepared by adsorbing the cationic surfactant hexadecyltrimethylammonium bromide (HDTMA-Br) on the external surface of the zeolite from coal ash. The zeolite structure stability was monitored during the characterization of the materials by FTIR, XDR and SEM. The structural parameters of surfactant-modified zeolite are very close to that of corresponding non-modified zeolite which indicates that the crystalline nature of the zeolite remained intact after required chemical treatment with HDTMA-Br molecules and heating treatment for drying. The most intense peaks in the FTIR spectrum of HDTMA-Br were observed in SMZ spectrum confirming adsorption of surfactant on zeolites. (author)

  16. Mercury release from fly ashes and hydrated fly ash cement pastes

    Science.gov (United States)

    Du, Wen; Zhang, Chao-yang; Kong, Xiang-ming; Zhuo, Yu-qun; Zhu, Zhen-wu

    2018-04-01

    The large-scale usage of fly ash in cement and concrete introduces mercury (Hg) into concrete structures and a risk of secondary emission of Hg from the structures during long-term service was evaluated. Three fly ashes were collected from coal-fired power plants and three blend cements were prepared by mixing Ordinary Portland cement (OPC) with the same amount of fly ash. The releasing behaviors of Hg0 from the fly ash and the powdered hydrated cement pastes (HCP) were measured by a self-developed Hg measurement system, where an air-blowing part and Hg collection part were involved. The Hg release of fly ashes at room temperature varied from 25.84 to 39.69 ng/g fly ash during 90-days period of air-blowing experiment. In contrast, the Hg release of the HCPs were in a range of 8.51-18.48 ng/g HCP. It is found that the Hg release ratios of HCPs were almost the same as those of the pure fly ashes, suggesting that the hydration products of the HCP have little immobilization effect on Hg0. Increasing temperature and moisture content markedly promote the Hg release.

  17. Plant nutrition on fly-ash

    Energy Technology Data Exchange (ETDEWEB)

    Rees, W J; Sidrak, G H

    1956-12-01

    Experiments were performed to determine the plant nutritional potential of fly ash. Chemical analysis indicates that it contains all the essential nutrients. It is deficient in nitrogen and only manganese and aluminum appear to be available in quantities toxic to plants. Barley and spinach grown on fly ash accumulate excessive quantities of Al and Mn in their leaves and exhibit symptoms of toxicities of these metals. Atriplex hastata grows vigorously on the ash, has a high Al and Mn leaf content, but does not show toxicity symptoms. Atriplex, barley and spinach grown at reduced N levels gave lower yields than the normal controls, but symptoms of N deficiency which were evident in barley and spinach were not observed in Atriplex. 17 references, 2 figures, 14 tables.

  18. Lunar ash flow with heat transfer.

    Science.gov (United States)

    Pai, S. I.; Hsieh, T.; O'Keefe, J. A.

    1972-01-01

    The most important heat-transfer process in the ash flow under consideration is heat convection. Besides the four important nondimensional parameters of isothermal ash flow (Pai et al., 1972), we have three additional important nondimensional parameters: the ratio of the specific heat of the gas, the ratio of the specific heat of the solid particles to that of gas, and the Prandtl number. We reexamine the one dimensional steady ash flow discussed by Pai et al. (1972) by including the effects of heat transfer. Numerical results for the pressure, temperature, density of the gas, velocities of gas and solid particles, and volume fraction of solid particles as function of altitude for various values of the Jeffreys number, initial velocity ratio, and two different gas species (steam and hydrogen) are presented.

  19. Production of mineral ash-wool

    International Nuclear Information System (INIS)

    Micevic, Z.; Djekic, S.

    1996-01-01

    The project entitled 'Production of Mineral Ash-Wool' presents a new technology of possible use of the fly ash, generated as a waste product from the fossil fueled power plants, as a basic raw material for manufacturing of different products from a new mineral ash-wool. The wide area of mineral ash-wool application (civil engineering, industry, power generation, etc.) and the advantages of this new technology (important raw material obtained free of charge, substitution of expensive silicate stone, use of electric energy for melting instead for coke, vicinity of factory location close to the fossil fueled power plant, lower product price, reduction of environmental pollution, etc.) have resulted in the performance of the bench scale tests. Positive results have been obtained, as a good initial base for the realization of this project. The named study as an detailed analysis has been carried out for the assessment of: supply and sales market, analysis of possible and selection of an optimal location of the factory in the frame of fossil fueled power plant 'Kosovo', selection of the production capacity and alternative preliminary technical designs of the factory for the mineral ash-wool production. For the studied alternatives, specifications and capital investments evaluations for equipment and works (mechanical, civil engineering and electromechanical part) have been made as well as assessments of production costs. Based on the performed economical and financial analyses, as well as the sensitivity analyses one could be concluded that the investments in the factory for the mineral ash-wool production is highly economically acceptable. (author). 1 fig., 1 tab., 3 refs

  20. The behavior of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Helena M.; Abelha, P.; Cabrita, I. [INETI-DEECA, Lisboa (Portugal); Lapa, N.; Oliveira, J.S. [UNL-Ubia, Monte de Caparica (Portugal)

    2003-07-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FRC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their reactor further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out, and the amount of unburned carbon leaving the combustor but captured in the cyclone was large enough to ensure substantial retention of mercury at low temperatures, and, hence, could contribute to an improvement of the mercury release, which still remains an issue of great concern to resolve during combustion of waste materials.

  1. The behaviour of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed.

    Science.gov (United States)

    Helena Lopes, M; Abelha, P; Lapa, N; Oliveira, J S; Cabrita, I; Gulyurtlu, I

    2003-01-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials.

  2. The behaviour of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed

    International Nuclear Information System (INIS)

    Helena Lopes, M.; Abelha, P.; Lapa, N.; Oliveira, J.S.; Cabrita, I.; Gulyurtlu, I.

    2003-01-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials

  3. Electrodialytic removal of Cd from biomass combustion fly ash

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Simonsen, Peter

    2004-01-01

    Due to a high concentration of Cd, biomass combustion fly ash often fails to meet the Danish legislative requirements for recycling on agricultural fields. In this work the potential of using the method Electrodialytic Remediation to reduce the concentration of Cd in different biomass combustion....... The initial Cd concentration in the ashes varied between 8.8 mg Cd/kg DM (co-firing ash) and 64 mg Cd/kg DM (pre-washed straw ash), and pH varied from 3.7 to 13.3. In spite of large differences in ash characteristics, the electrodialytic remediation experiments indicated a good remediation potential for all...... four ashes. Final Cd concentrations below 2.0 mg Cd/kg were reached in all ashes within 14 days of remediation and legislative requirements were met. After further optimization of the remediation process on the pre-washed straw ash, limiting concentrations were reached after only 48 hours...

  4. Utilization of mixed pond ash in integrated steel plant for ...

    Indian Academy of Sciences (India)

    Unknown

    manufacturing superior quality bricks. PIYUSH ... Nearly 73% of India's total installed power generation capacity ... used to produce superior quality ash bricks, which would be more ..... Kumar V and Sharma P 1999 Fly ash management in iron.

  5. Emerald ash borer infestation rates in Michigan, Ohio, and Indiana.

    Science.gov (United States)

    Eric L. Smith; Andrew J. Storer; Bryan K. Roosien

    2009-01-01

    The goal of this study was to obtain an estimate of the infestation rate of ash trees with emerald ash borer (EAB) (Agrilus planipennis, Fairmaire; Coleoptera; Buprestidae), across its primary infestation zone of...

  6. Effect of Azolla Based - Organic Fertilizer, Rock Phosphate and Rice Hull Ash on Rice Yield and Chemical Properties of Alfisols

    Directory of Open Access Journals (Sweden)

    Sudadi

    2014-07-01

    Full Text Available The application of chemical fertilizer for long time may adverse soil environment. Organic agriculture, for example combination use of azolla based-organic fertilizer, phosphate rock and rice hull ash, was one of ways that able to recover it. Research was conducted in Sukosari, Jumantono, Karanganyar while soi chemical properties analysis was analysed in Soil Chemistry and Fertility Laboratory, Fac. of Agriculture, Sebelas Maret University April to November 2013. Research design used was RAKL with 5 treatments, each repeated 5 times. The treatments applied were P0 (control, P1 ( azola inoculum dosage 250 g/m2 + phosphate rock + rice hull ash equal to 150 kg/ha KCl, P2 (azola inoculum dosage 500 g/m2 + phosphate rock equal to 150kg/ha, SP-36 + rice hull ash equal to 100 kg/ha KCl, P3 (manure dosage of 5 ton/ha,P4 (Urea 250 kg/ha + SP-36 150 kg/ha + KCl 100 kg/ha. Data analysed statistically by F test (Fisher test with level of confident 95% followed by DMRT (Duncan Multiple Range Test if any significant differences. The result showed that the treatment combination of azolla, phosphate rock and rice hull ash increase soil organic matter content, cation exchange capacity, available-P and exchangeable-K as well as rice yield ( (at harvest-dry grain weight and milled-dry grain weight.

  7. High performance of treated and washed MSWI bottom ash granulates as natural aggregate replacement within earth-moist concrete.

    Science.gov (United States)

    Keulen, A; van Zomeren, A; Harpe, P; Aarnink, W; Simons, H A E; Brouwers, H J H

    2016-03-01

    Municipal solid waste incineration bottom ash was treated with specially designed dry and wet treatment processes, obtaining high quality bottom ash granulate fractions (BGF) suitable for up to 100% replacement of natural gravel in concrete. The wet treatment (using only water for separating and washing) significantly lowers the leaching of e.g. chloride and sulfate, heavy metals (antimony, molybdenum and copper) and dissolved organic carbon (DOC). Two potential bottom ash granulate fractions, both in compliance with the standard EN 12620 (aggregates for concrete), were added into earth-moist concrete mixtures. The fresh and hardened concrete physical performances (e.g. workability, strength and freeze-thaw) of high strength concrete mixtures were maintained or improved compared with the reference mixtures, even after replacing up to 100% of the initial natural gravel. Final element leaching of monolithic and crushed granular state BGF containing concretes, showed no differences with the gravel references. Leaching of all mixtures did not exceed the limit values set by the Dutch Soil Quality Degree. In addition, multiple-life-phase emission (pH static test) for the critical elements of input bottom ash, bottom ash granulate (BGF) and crushed BGF containing concrete were assessed. Simulation pH lowering or potential carbonation processes indicated that metal (antimony, barium, chrome and copper) and sulfate element leaching behavior are mainly pH dominated and controlled, although differ in mechanism and related mineral abundance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Effects of different treatments of fly ash and mining soil on growth and antioxidant protection of Indian wild rice.

    Science.gov (United States)

    Bisoi, Sidhanta Sekhar; Mishra, Swati S; Barik, Jijnasa; Panda, Debabrata

    2017-05-04

    The aim of the present study was investigation of the effects of fly ash and mining soil on growth and antioxidant protection of two cultivars of Indian wild rice (Oryza nivara and Oryza rufipogon) for possible phytoremediation and restoration of metal-contaminated site. In this study, Indian wild rice showed significant changes in germination, growth, and biochemical parameters after exposure to different ratio of fly ash and mining soil with garden soil. There was significant reduction of germination, fresh weight, dry weight, leaf chlorophyll content, leaf area, Special Analysis Device Chlorophyll (SPAD) Index, proteins, and activities of antioxidant enzymes in both cultivars of the wild rice grown in 100% fly ash and mining soil compared to the plants grown in 100% garden soil. Results from this study showed that in both cultivars of wild rice, all growth and antioxidant parameters increased when grown in 50% fly ash and mining soil. Taken together, Indian wild rice has the capacity to tolerate 50% of fly ash and mining soil, and can be considered as a good candidate for possible phytoremediation of contaminated soils.

  9. Effect of municipal solid waste incinerator types on characteristics of ashes from different air pollution control devices.

    Science.gov (United States)

    Lu, Chien-Hsing; Chuang, Kui-Hao

    2016-01-01

    The purpose of this paper is to investigate the characteristics of fly and bottom ashes sampled from both fluidized bed (FB) and mass-burning (MB) municipal solid waste incinerators (MSWIs), respectively. Fly ashes from different locations at FB and MB MSWIs equipped with a cyclone, a semi-dry scrubber, and a bag filter as air pollution control devices were examined to provide the baseline information between physicochemical properties and leaching ability. Experimental results of leachability indicated that the bag filter fly ash (FB-FA(B)) from the FB incinerator meets Taiwan regulatory standards set through the toxicity characteristic leaching procedure. X-ray diffraction results revealed the presence of Cr5O12 and Pb2O3 in the cyclone fly ash (MB-FA(C)) and bag filter fly ash (MB-FA(B)), respectively, from the MB incinerator. To observe lead incorporation mechanism, mixture of simulate lead-laden waste with bed material were fired between 600 °C and 900 °C in a laboratory scale FB reactor. The results clearly demonstrate a substantial decrease in lead leaching ratio for products with an appropriate temperature. The concentration of Pb in the MB-FA(B) was 250 times that in the FB-FA(B), suggesting that incineration of MSW in FB is a good strategy for stabilizing hazardous metals.

  10. Selenium bioaccumulation in fish exposed to coal ash at the Tennessee Valley Authority Kingston spill site.

    Science.gov (United States)

    Mathews, Teresa J; Fortner, Allison M; Jett, R Trent; Morris, Jesse; Gable, Jennifer; Peterson, Mark J; Carriker, Neil

    2014-10-01

    In December 2008, 4.1 million cubic meters of coal ash were released into the Emory and Clinch Rivers by the Tennessee Valley Authority Kingston Fossil Plant. Coal ash contains several contaminants, including the bioaccumulative metalloid selenium (Se). Because Se is predominantly accumulated in aquatic organisms through dietary rather than aqueous exposure, tissue-based toxicity thresholds for Se are currently being considered. The proposed threshold concentrations range between 4 μg/g and 9 μg/g Se (dry wt.) in whole body fish, with a proposed fillet threshold of 11.8 μg/g. In the present study, the authors examined the spatial and temporal trends in Se bioaccumulation and examined the relationship between the Se content in fillets and in whole bodies of fish collected around the Kingston spill site to determine whether Se bioaccumulation was a significant concern at the ash spill site. Whereas Se concentrations in fish (whole bodies and fillets) were elevated at sampling locations affected by the Kingston ash spill relative to reference locations, concentrations do not appear to be above risk thresholds and have not been increasing over the 5-yr period since the spill. These findings are not only relevant to guiding the human health and ecological risk assessments at the Kingston ash spill site, but because of current national discussions on appropriate guidelines for Se in fish as well for the disposal of coal combustion wastes, the results are also relevant to the general understanding of Se bioaccumulation in contaminated water bodies. © 2014 SETAC.

  11. Microphysical Properties of Alaskan Volcanic Ash

    Science.gov (United States)

    Puthukkudy, A.; Espinosa, R.; Rocha Lima, A.; Remer, L.; Colarco, P. R.; Whelley, P.; Krotkov, N. A.; Young, K.; Dubovik, O.; Wallace, K.; Martins, J. V.

    2017-12-01

    Volcanic ash has the potential to cause a variety of severe problems for human health and the environment. Therefore, effective monitoring of the dispersion and fallout from volcanic ash clouds and characterization of the aerosol particle properties are essential. One way to acquire information from volcanic clouds is through satellite remote sensing: such images have greater coverage than ground-based observations and can present a "big picture" perspective. A challenge of remote sensing is that assumptions of certain properties of the target are often a pre-requisite for making accurate and quantitative retrievals. For example, detailed information about size distribution, sphericity, and optical properties of the constituent matter is needed or must be assumed. The same kind of information is also needed for atmospheric transport models to properly simulate the dispersion and fallout of volcanic ash. Presented here is a laboratory method to determine the microphysical and optical properties of volcanic ash samples collected from two Alaskan volcanoes with markedly different compositions. Our method uses a Polarized Imaging Nephelometer (PI-Neph) and a system that re-suspends the particles in an air flow. The PI-Neph measures angular light scattering and polarization of the re-suspended particles from 3o to 175o in scattering angle, with an angular resolution of 1o . Primary measurements include phase function and polarized phase function at three wavelengths (445nm, 532nm, and 661nm). Size distribution, sphericity, and complex refractive index are retrieved indirectly from the PI-Neph measurements using the GRASP (Generalized Retrieval of Aerosol and Surface Properties) inversion algorithm. We report the results of this method applied to samples from the Mt. Okmok (2008) and Mt. Katmai (1912) volcanic eruptions. To our knowledge, this is the first time direct measurements of phase matrix elements of ash from Mt. Okmok and Mt. Katmai have been reported. Retrieved

  12. Economic metal recovery from fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Gilliam, T.M.; Canon, R.M.; Egan, B.Z.; Kelmers, A.D.; Seeley, F.G.; Watson, J.S.

    1982-08-01

    Results are presented to show that fly ash can be an economical source of Al/sub 2/O/sub 3/, Fe/sub 2/O/sub 3/ and several other metals. Two processes are examined in detail, the direct acid leach of ash with hydrochloric acid and a pressure digestion-acid leach method. An economic evaluation is presented for each process, and direct acid leaching is considered the most attractive process. The benefits derived from using such a process are discussed. (15 refs.)

  13. Softening behaviour of brown coal ashes. Influence of ash components and gas atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Hegermann, R; Huettinger, K J [Karlsruhe Univ. (T.H.) (Germany, F.R.). Inst. fuer Chemische Technik

    1990-03-01

    The softening behaviour of brown coal ashes during gasification is important for three reasons: (1) Formation of large agglomerates, (2) inactivation of catalytically active ash components, (3) encapsulation of parts of the coal. The softening behaviour of the ashes was studied with a high temperature dilatometer at ambient pressure in various atmospheres (air, CO{sub 2}, Ar/H{sub 2}O, Ar, H{sub 2}/H{sub 2}O, H{sub 2}) using a push-rod with a conical tip. The heating rate was 5 Kmin{sup -1}, the final temperature 1000deg C, the residence time 1 h. (orig.).

  14. Utilization options for fly ash, bottom ash, and slag in Eastern Europe

    Energy Technology Data Exchange (ETDEWEB)

    Manz, O.E.

    1995-12-01

    Since 1967, at least six ash utilization symposiums have been held in the United States, with papers presented by several European authors on the utilization of coal by-products in Eastern Europe. There is currently over 80,000 megawatts of installed coal-fired capacity available in that region. Unfortunately, of the 117,778,000 tonnes of fly ash, bottom ash, and slag produced in Eastern Europe in 1989, only 13% was utilized. This paper outlines the research and levels and kinds of coal by-product utilization taking place in Eastern Europe since the late 1960s.

  15. Ash fusion temperatures and the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.; Wall, T.F.; Creelman, R.A.; Gupta, R. [Univ. of Newcastle, Callaghan (Australia)

    1996-12-31

    A mechanistic study is detailed in which coal ash is heated with its shrinkage measured continuously up to a temperature of 1600{degrees}C. The temperatures corresponding to the rapid rate of shrinkage are shown to correspond to the formation of eutectics identified on phase diagrams. Samples were therefore heated to these temperatures, cooled rapidly and examined with an SEM to identify the associated chemical and physical changes. The progressive changes in the range of chemical analysis (from SEM), the extent of undissolved ash particles and porosity were then quantified and related to homogenization, viscosity and ash fusion mechanisms.

  16. Ash fusion temperatures and the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Wall, T.F.; Creelman, R.A.; Gupta, R.; Gupta, S. [Univ. of Newcastle (Australia)

    1996-10-01

    A mechanistic study is detailed in which coal ash is heated with the shrinkage and electrical resistance measured continuously up to a temperature of 1600{degrees}C. The temperatures corresponding to rapid rates of shrinkage are shown to correspond to the formation of eutectics identified on phase diagrams. Samples where therefore heated to these temperatures, cooled rapidly and examined with an SEM to identify the associated chemical and physical changes. The progressive changes in the range of chemical analysis (from SEM), the extent of undissolved ash particles and porosity are then quantified and related to the shrinkage events and standard ash fusion temperatures.

  17. Associative properties of 137Cs in biofuel ashes

    International Nuclear Information System (INIS)

    Ravila, A.; Holm, E.

    1999-01-01

    The present study aims to reveal how radiocesium is associated to the ash particles derived from biofuel combustion. A sequential extraction procedure was carried out for the characterisation of radiocesium speciation in ash generated by different fuels and burner types. The ash types considered were fly ash and bottom ash collected from Swedish district heating plants using bark wood or peat as fuel. A fraction of the radiocesium in biofuel ash can easily become solubilised and mobilised by water and also, a significant fraction of the radionuclides can be bound to the ash particles in cation-exchangeable forms. Therefore, at using the ash derived from biofuels to recycle mineral nutrients for forestry or short rotation coppicing, radiocesium solubilised and leached from the ash by rains has a potential to rather quickly enter the rooting zone of forest vegetation or energy crops. On the other hand, radiocesium strongly bound to the ash will migrate slowly into the soil column with the successive accumulation of litter and in the process act to maintain the external dose rate at an elevated level for a long time. The results of the sequential extraction procedure and activity determination of the different extracted fractions implies that the bioavailable fraction of radiocesium in ash from bark, wood or peat is in the range between 20-85% of the total ash contents. Peat ash collected from a powder burner strongly retained a large fraction (70-90%) of its radiocesium content while the peat ash from a continuos fluidized bed type burner retained nearly 100% of the radiocesium in the bottom ash and only about 15% in the fly ash

  18. Possibilities for the Use of Wood Ashes in Agriculture

    OpenAIRE

    Barbara Symanowicz; Marcin Becher; Dawid Jaremko; Korneliusz Skwarek

    2018-01-01

    The aim of the study was to determine the agricultural usefulness of the ashes obtained following the combustion of wood of fourteen tree species (pear tree, apple tree, aspen, ash, alder, birch, poplar, hornbeam, pine, common walnut, oak, hazel, bird cherry and spruce) in home fireplaces. The following physical properties of the ashes were determined: colour, solubility, porosity, absorbability, compression strength, degree of fineness, moisture content and spreadability. In the ashes...

  19. Possibilities for stabilization of fly ash from REK 'Bitola' dump

    International Nuclear Information System (INIS)

    Petrushevska, Ljubica; Ivanovska, Pavlina; Ilievski, Zlatko; Peeva, Liljana

    2002-01-01

    The Coal Power Plants environmental problems, mainly, arise from deposited fly ash-solid particles which, under the influence of the wind, heavily pollute the atmospheric air. Prevention of the environmental problems, coming from spraying from the energetic dumps, is achieved with technical and biological stabilization of dumped fly ash. The choice of the stabilization means and methods depends on the physical-chemical properties of the ash. Therefore, the stabilization possibilities of REK 'Bitola' fly ash were investigated. (Original)

  20. Granulated wood ash to forest soil - Ecological effects

    International Nuclear Information System (INIS)

    Rosen, K.; Eriksson, H.; Clarholm, M.; Lundkvist, H.; Rudebeck, A.

    1993-01-01

    This report describes research concerning ecological effects of wood ash recycling to forest soils. The main part of the minerals in the wood fuels are retained in the ashes after combustion. By returning the ashes back to the cleared forest areas, the mineral losses can be reduced. Adding ashes and limestone is a method to vitalize acidified forest soils and restore the production capacity. 48 refs, 26 figs, 8 tabs

  1. Characteristics of silica rice husk ash from Mojogedang Karanganyar Indonesia

    Science.gov (United States)

    Suryana, R.; Iriani, Y.; Nurosyid, F.; Fasquelle, D.

    2018-05-01

    Indonesia is one of the countries in the world as the most abundant rice producer. Many researchers have demonstrated that the highest composition in the rice husk ash (RHA) is silica. Some of the advantages in utilizing silica as the raw material is the manufacture of ceramics, zeolite synthesis, fabrication of glass, electronic insulator materials, and as a catalyst. The amount of silica from rice husk ash is different for each region. Therefore, the study of silica from RHA is still promising, especially rice organic fertilizers. In this study, the rice came from Mojogedang Karanganyar Indonesia. Rice husk was dried under the solar radiation. Then the rice husk was heated in two steps: the first step at a temperature of 300°C and the second step at a temperature of 1200°C with a holding time at 2 h and 1 h, respectively. Furthermore, the temperature of the second step was varied at 1400 °C and 1600 °C. This heating process produced RHA. The content of RHA was observed on the EDAX spectrums while the morphology was observed from SEM images. The crystal structure of RHA was determined from XRD spectrums. The EDAX spectrums showed that RHA composition was dominated by elements Si and O for all the heating temperature. SEM images showed an agglomeration towards larger domains as heating temperatures increase. Analysis of XRD spectra is polycrystalline silica formed with the significant crystal orientation at 101, 102 and 200. The intensity of 101 increases significantly with increasing temperature. It is concluded that the crystal growth in the direction of 101 is preferred.

  2. Effect of municipal solid waste ash on comprehensive strength ...

    African Journals Online (AJOL)

    The blocks were moulded in a CINVA-Ram machine by replacing 0%, 2%, 5% and 10% of municipal solid waste ash (MSW ash) as a stabilizing agent. The compressive strengths of individual blocks were obtained after curing for 7, 14 and 28 days. The 2%MSW ash replacement gave the highest compressive strength and ...

  3. Upshot of Elevated Temperature on Performance Facet of Fly Ash ...

    African Journals Online (AJOL)

    This study investigates the effects of elevated temperature variation on the compressive strength of Fly Ash/Ordinary Portland Cement (OPC) Laterized concrete ... and 10% Fly ash content at 2500C. This is an indication that the strength of Fly ash/OPC Laterized concrete is generally sufficient for use at elevated temperature ...

  4. Improving volcanic ash forecasts with ensemble-based data assimilation

    NARCIS (Netherlands)

    Fu, Guangliang

    2017-01-01

    The 2010 Eyjafjallajökull volcano eruption had serious consequences to civil aviation. This has initiated a lot of research on volcanic ash forecasting in recent years. For forecasting the volcanic ash transport after eruption onset, a volcanic ash transport and diffusion model (VATDM) needs to be

  5. Environmental effects of ash application in forest ecosystems

    DEFF Research Database (Denmark)

    Hansen, Mette

    of ashes being produced and the export of nutrients from the forests. This PhD project aims at investigating how ash application in forest ecosystems affects soil and soil solution properties and whether ash application can be used in a Danish context without environmental harm but with positive effects...

  6. Economic analysis of emerald ash borer (Coleoptera: Buprestidae) management options.

    Science.gov (United States)

    Vannatta, A R; Hauer, R H; Schuettpelz, N M

    2012-02-01

    Emerald ash borer, Agrilus planipennis (Fairmaire) (Coleoptera: Buprestidae), plays a significant role in the health and extent of management of native North American ash species in urban forests. An economic analysis of management options was performed to aid decision makers in preparing for likely future infestations. Separate ash tree population valuations were derived from the i-Tree Streets program and the Council of Tree and Landscape Appraisers (CTLA) methodology. A relative economic analysis was used to compare a control option (do-nothing approach, only removing ash trees as they die) to three distinct management options: 1) preemptive removal of all ash trees over a 5 yr period, 2) preemptive removal of all ash trees and replacement with comparable nonash trees, or 3) treating the entire population of ash trees with insecticides to minimize mortality. For each valuation and management option, an annual analysis was performed for both the remaining ash tree population and those lost to emerald ash borer. Retention of ash trees using insecticide treatments typically retained greater urban forest value, followed by doing nothing (control), which was better than preemptive removal and replacement. Preemptive removal without tree replacement, which was the least expensive management option, also provided the lowest net urban forest value over the 20-yr simulation. A "no emerald ash borer" scenario was modeled to further serve as a benchmark for each management option and provide a level of economic justification for regulatory programs aimed at slowing the movement of emerald ash borer.

  7. Characterization of fly ash from bio and municipal waste

    DEFF Research Database (Denmark)

    Lima, Ana T.; Ottosen, Lisbeth M.; Pedersen, Anne Juul

    2008-01-01

    the co-combustion of wood and oil. The focus is laid on differences in ash characteristics and on the mobility of Cd and Cr. These two heavy metals are chosen because Cd is the problematic heavy metal in bio ashes and Cr is problematic in many ash stabilization methods (in the Cr(VI) state). Based...

  8. Quantification of fusion in ashes from solid fuel combustion

    DEFF Research Database (Denmark)

    Hansen, Lone Aslaug; Frandsen, Flemming; Dam-Johansen, Kim

    1999-01-01

    The fusion of ashes produced during solid fuel combustion greatly affects the tendency of these ashes to cause operational problems in utility boilers. In this paper, a new and quantitative laboratory method for assessing the fusion of ashes based on simultaneous thermal analysis, STA, is described...

  9. Volcanic Ash from the 1999 Eruption of Mount Cameroon Volcano ...

    African Journals Online (AJOL)

    2008-10-21

    Oct 21, 2008 ... fluorine (F) content of the ash was determined by the selective ion electrode method. The results ... the main mineral in volcanic ash responsible for causing silicosis. The F ... volcanic ash with little or no attention to the < 4 µm.

  10. Optimizing and Characterizing Geopolymers from Ternary Blend of Philippine Coal Fly Ash, Coal Bottom Ash and Rice Hull Ash

    Directory of Open Access Journals (Sweden)

    Martin Ernesto Kalaw

    2016-07-01

    Full Text Available Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC, which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerged as a sustainable option vis-à-vis OPC for three reasons: (1 their technical properties are comparable if not better; (2 they can be produced from industrial wastes; and (3 within reasonable constraints, their production requires less energy and emits significantly less CO2. In the Philippines, the use of coal ash, as the alumina- and silica- rich geopolymer precursor, is being considered as one of the options for sustainable management of coal ash generation from coal-fired power plants. However, most geopolymer mixes (and the prevalent blended OPC use only coal fly ash. The coal bottom ash, having very few applications, remains relegated to dumpsites. Rice hull ash, from biomass-fired plants, is another silica-rich geopolymer precursor material from another significantly produced waste in the country with only minimal utilization. In this study, geopolymer samples were formed from the mixture of coal ash, using both coal fly ash (CFA and coal bottom ash (CBA, and rice hull ash (RHA. The raw materials used for the geopolymerization process were characterized using X-ray fluorescence spectroscopy (XRF for elemental and X-ray diffraction (XRD for mineralogical composition. The raw materials’ thermal stability and loss on ignition (LOI were determined using thermogravimetric analysis (TGA and reactivity via dissolution tests and inductively-coupled plasma mass spectrometry (ICP analysis. The mechanical, thermal and microstructural properties of the geopolymers formed were analyzed using compression tests, Fourier transform infra-red spectroscopy (FTIR

  11. Optimizing and Characterizing Geopolymers from Ternary Blend of Philippine Coal Fly Ash, Coal Bottom Ash and Rice Hull Ash.

    Science.gov (United States)

    Kalaw, Martin Ernesto; Culaba, Alvin; Hinode, Hirofumi; Kurniawan, Winarto; Gallardo, Susan; Promentilla, Michael Angelo

    2016-07-15

    Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC), which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerged as a sustainable option vis-à-vis OPC for three reasons: (1) their technical properties are comparable if not better; (2) they can be produced from industrial wastes; and (3) within reasonable constraints, their production requires less energy and emits significantly less CO₂. In the Philippines, the use of coal ash, as the alumina- and silica- rich geopolymer precursor, is being considered as one of the options for sustainable management of coal ash generation from coal-fired power plants. However, most geopolymer mixes (and the prevalent blended OPC) use only coal fly ash. The coal bottom ash, having very few applications, remains relegated to dumpsites. Rice hull ash, from biomass-fired plants, is another silica-rich geopolymer precursor material from another significantly produced waste in the country with only minimal utilization. In this study, geopolymer samples were formed from the mixture of coal ash, using both coal fly ash (CFA) and coal bottom ash (CBA), and rice hull ash (RHA). The raw materials used for the geopolymerization process were characterized using X-ray fluorescence spectroscopy (XRF) for elemental and X-ray diffraction (XRD) for mineralogical composition. The raw materials' thermal stability and loss on ignition (LOI) were determined using thermogravimetric analysis (TGA) and reactivity via dissolution tests and inductively-coupled plasma mass spectrometry (ICP) analysis. The mechanical, thermal and microstructural properties of the geopolymers formed were analyzed using compression tests, Fourier transform infra-red spectroscopy (FTIR), scanning

  12. Drying and energy technologies

    CERN Document Server

    Lima, A

    2016-01-01

    This book provides a comprehensive overview of essential topics related to conventional and advanced drying and energy technologies, especially motivated by increased industry and academic interest. The main topics discussed are: theory and applications of drying, emerging topics in drying technology, innovations and trends in drying, thermo-hydro-chemical-mechanical behaviors of porous materials in drying, and drying equipment and energy. Since the topics covered are inter- and multi-disciplinary, the book offers an excellent source of information for engineers, energy specialists, scientists, researchers, graduate students, and leaders of industrial companies. This book is divided into several chapters focusing on the engineering, science and technology applied in essential industrial processes used for raw materials and products.

  13. Characterization of ash pond ashes from 3rd thermal power plant by SEM/EDX and XRD methods

    OpenAIRE

    A Minjigmaa; Ts Zolzaya; E Bayanjargal; B Davaabal; J Temuujin

    2014-01-01

      Coal combustion by products from ash pond of 3rdthermal power plant of Ulaanbaatar city have been collected in 2010 and 2013 years. The ash samples have been characterized by XRD, XRF and SEM-EDX methods in order to evaluate their chemical and mineralogical composition changes with disposed times. The mineralogical composition of ash varies with time though the chemical composition of the ashes were close each other. Possibly, inefficient operating condition of the TPS shows influence on th...

  14. Ambient Dried Aerogels

    Science.gov (United States)

    Jones, Steven M.; Paik, Jong-Ah

    2013-01-01

    A method has been developed for creating aerogel using normal pressure and ambient temperatures. All spacecraft, satellites, and landers require the use of thermal insulation due to the extreme environments encountered in space and on extraterrestrial bodies. Ambient dried aerogels introduce the possibility of using aerogel as thermal insulation in a wide variety of instances where supercritically dried aerogels cannot be used. More specifically, thermoelectric devices can use ambient dried aerogel, where the advantages are in situ production using the cast-in ability of an aerogel. Previously, aerogels required supercritical conditions (high temperature and high pressure) to be dried. Ambient dried aerogels can be dried at room temperature and pressure. This allows many materials, such as plastics and certain metal alloys that cannot survive supercritical conditions, to be directly immersed in liquid aerogel precursor and then encapsulated in the final, dried aerogel. Additionally, the metalized Mylar films that could not survive the previous methods of making aerogels can survive the ambient drying technique, thus making multilayer insulation (MLI) materials possible. This results in lighter insulation material as well. Because this innovation does not require high-temperature or high-pressure drying, ambient dried aerogels are much less expensive to produce. The equipment needed to conduct supercritical drying costs many tens of thousands of dollars, and has associated running expenses for power, pressurized gasses, and maintenance. The ambient drying process also expands the size of the pieces of aerogel that can be made because a high-temperature, high-pressure system typically has internal dimensions of up to 30 cm in diameter and 60 cm in height. In the case of this innovation, the only limitation on the size of the aerogels produced would be in the ability of the solvent in the wet gel to escape from the gel network.

  15. Slowing ash mortality: a potential strategy to slam emerald ash borer in outlier sites

    Science.gov (United States)

    Deborah G. McCullough; Nathan W. Siegert; John Bedford

    2009-01-01

    Several isolated outlier populations of emerald ash borer (Agrilus planipennis Fairmaire) were discovered in 2008 and additional outliers will likely be found as detection surveys and public outreach activities...

  16. Dry etching for microelectronics

    CERN Document Server

    Powell, RA

    1984-01-01

    This volume collects together for the first time a series of in-depth, critical reviews of important topics in dry etching, such as dry processing of III-V compound semiconductors, dry etching of refractory metal silicides and dry etching aluminium and aluminium alloys. This topical format provides the reader with more specialised information and references than found in a general review article. In addition, it presents a broad perspective which would otherwise have to be gained by reading a large number of individual research papers. An additional important and unique feature of this book

  17. Inflammation in dry eye.

    Science.gov (United States)

    Stern, Michael E; Pflugfelder, Stephen C

    2004-04-01

    Dry eye is a condition of altered tear composition that results from a diseased or dysfunctional lacrimal functional unit. Evidence suggests that inflammation causes structural alterations and/or functional paralysis of the tear-secreting glands. Changes in tear composition resulting from lacrimal dysfunction, increased evaporation and/or poor clearance have pro-inflammatory effects on the ocular surface. This inflammation is responsible in part for the irritation symptoms, ocular surface epithelial disease, and altered corneal epithelial barrier function in dry eye. Anti-inflammatory therapies for dry eye target one or more of the inflammatory mediators/pathways that have been identified in dry eye.

  18. Drying hardwood lumber

    Energy Technology Data Exchange (ETDEWEB)

    Chow, A T

    1988-11-14

    Dried lumber is a high-value-added product, especially when it is of high quality. Lumber damaged during the drying operation can represent substantial lost revenue. It has been demonstrated that dehumidification kilns can improve lumber quality, and reduce energy consumption over conventional drying methods. A summary of the literature on drying hardwood lumber, particularly using heat pump dehumidification, has been prepared to allow the information to be readily accessible to Ontario Hydro personnel who work with customers in the lumber industry. For that purpose, this summary has been prepared from the perspective of the customer, a dry kiln operator. Included are brief descriptions of drying schedules, precautions needed to minimize drying defects in the lumber, and rules-of-thumb for selecting and estimating the capital cost of the drying equipment. A selection of drying schedules and moisture contents of green lumber, a glossary of lumber defects and brief descriptions of the possible preventive measures are also included. 10 refs., 8 figs., 4 tabs.

  19. FLY ASH: AN ALTERNATIVE TO POWDERED ACTIVATED ...

    African Journals Online (AJOL)

    Preferred Customer

    The peaks observed at 1546 and 1511 cm−1 correspond to CO3. 2- group. Symmetric .... The values of RL reported in Table 5 obtained were less than one, indicating that the adsorption of eosin dye ... This work. Coal fly ash. Crystal Violet.

  20. Damping of radioactivity of the Bikini ashes

    Energy Technology Data Exchange (ETDEWEB)

    Horie, K

    1955-01-01

    The radioactivity (..beta..- and ..gamma..-radiation) of the H-bomb ashes was measured over a period of 600 days by means of an electroscope and a Geiger-Mueller counter. Absorption by Al foils shows that the half-life is shorter for radiation of lower energy.

  1. Zeolite from fly ash: synthesis and characterization

    Indian Academy of Sciences (India)

    Unknown

    to attempt making zeolite from fly ash (Höller and Wir- sching 1985; Henmi ... thermal treatment method to synthesize low silica NaX- type zeolite from .... catalytic applications. Mixture of ... amount of Fe2O3 and the oxides of Mg, Ca, P, Ti etc. The chemical ..... This work is partly supported by the Ministry of Human. Resource ...

  2. Zeolite from fly ash: synthesis and characterization

    Indian Academy of Sciences (India)

    Coal fly ash was used to synthesize X-type zeolite by alkali fusion followed by hydrothermal treatment. The synthesized zeolite was characterized using various techniques such as X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, BET method for surface area measurement etc.

  3. Emerald ash borer genetics: an update

    Science.gov (United States)

    Alicia M. Bray; Leah S. Bauer; Robert A. Haack; Therese Poland; James J. Smith

    2008-01-01

    Emerald ash borer (EAB), Agrilus planipennis Fairmaire, samples were collected from introduced sites in Michigan, Ohio, Indiana, Pennsylvania, Illinois, and Ontario, Canada, as well as native sites in China, Japan, and South Korea with the help of a network of collaborators. The beetles were analyzed using DNA sequences from mitochondrial cytochrome...

  4. Phosphorus recovery from sewage sludge char ash

    NARCIS (Netherlands)

    Atienza-Martinez, M.; Gea, G.; Arauzo, J.; Kersten, Sascha R.A.; Kootstra, A.M.J.

    2014-01-01

    Phosphorus was recovered from the ash obtained after combustion at different temperatures (600 °C, 750 °C and 900 °C) and after gasification (at 820 °C using a mixture of air and steam as fluidising agent) of char from sewage sludge fast pyrolysis carried out at 530 °C. Depending on the leaching

  5. 1997 Arthur Ashe Jr. Sport Scholars Awards.

    Science.gov (United States)

    Roach, Ronald

    1997-01-01

    Winners of the "Black Issues in Higher Education" Arthur Ashe Jr. 1997 athletes of the year, one male and one female, are profiled and Sport Scholars are listed for baseball, softball, basketball, fencing, archery, football, handball, soccer, field hockey, crew, swimming, gymnastics, tennis, squash, golf, volleyball, lacrosse, wrestling, water…

  6. Water table response to harvesting and simulated emerald ash borer mortality in black ash wetlands in Minnesota, USA

    Science.gov (United States)

    Robert A. Slesak; Christian F. Lenhart; Kenneth N. Brooks; Anthony W. D' Amato; Brian J. Palik

    2014-01-01

    Black ash wetlands are seriously threatened because of the invasive emerald ash borer (EAB). Wetland hydrology is likely to be modified following ash mortality, but the magnitude of hydrological impact following loss via EAB and alternative mitigation harvests is not clear. Our objective was to assess the water table response to simulated EAB and harvesting to...

  7. Radiobiological waste treatment-ashing treatment and immobilization with cement

    Energy Technology Data Exchange (ETDEWEB)

    Shengtao, Feng; Li, Gong; Li, Cheng; Benli, Wang; Lihong, Wang [China Inst. for Radiation Protection, Taiyuan, Shanxi (China)

    1997-02-01

    This report describes the results of the study on the treatment of radioactive biological waste in the China Institute for Radiation Protection (CIRP). The possibility of radiobiological waste treatment was investigated by using a RAF-3 type rapid ashing apparatus together with the immobilization of the resulted ash. This rapid ashing apparatus, developed by CIRP, is usually used for pretreatment of samples prior to chemical analysis and physical measurements. The results show that it can ash 3 kg of animal carcasses a batch, the ashing time is 5-7 h and the ash content is less than 4 wt%. The ashing temperature not exceeding 450 deg. C was used without any risk of high losses of radionuclides. The ash from the rapid ashing apparatus was demonstrated to be immobilized with ordinary silicate cement. The optimum cement/ash/water formulation of the cemented waste form was 35 {+-} 5 wt% cement, 29 {+-} 2 wt% water, and 36 {+-} 6 wt% ash. The performance of the waste form was in compliance with the technical requirements except for impact resistance. Mixing additives in immobilization formulations can improve the performance of the cemented ash waste form. The additives chosen were DH{sub 4A} flow promoter as a cement additive and vermiculite or zeolite as a supplement. The recommended formulation, i.e. an improved formulation of the cemented ash waste form is that additives DH{sub 4A} flow promoter and vermiculite (or zeolite) are added on the ground of optimum cement/ash/water formulation of the cemented waste form, the dosage of water, DH{sub 4A} and vermiculite (or zeolite) is 70 wt%, 0.5 wt% and {<=} 5 wt% of the cement dosage, respectively. The cemented ash waste forms obtained meet all the requirements for disposal. (author). 12 refs, 7 figs, 13 tabs.

  8. Radiobiological waste treatment-ashing treatment and immobilization with cement

    International Nuclear Information System (INIS)

    Feng Shengtao; Gong Li; Cheng Li; Wang Benli; Wang Lihong

    1997-01-01

    This report describes the results of the study on the treatment of radioactive biological waste in the China Institute for Radiation Protection (CIRP). The possibility of radiobiological waste treatment was investigated by using a RAF-3 type rapid ashing apparatus together with the immobilization of the resulted ash. This rapid ashing apparatus, developed by CIRP, is usually used for pretreatment of samples prior to chemical analysis and physical measurements. The results show that it can ash 3 kg of animal carcasses a batch, the ashing time is 5-7 h and the ash content is less than 4 wt%. The ashing temperature not exceeding 450 deg. C was used without any risk of high losses of radionuclides. The ash from the rapid ashing apparatus was demonstrated to be immobilized with ordinary silicate cement. The optimum cement/ash/water formulation of the cemented waste form was 35 ± 5 wt% cement, 29 ± 2 wt% water, and 36 ± 6 wt% ash. The performance of the waste form was in compliance with the technical requirements except for impact resistance. Mixing additives in immobilization formulations can improve the performance of the cemented ash waste form. The additives chosen were DH 4A flow promoter as a cement additive and vermiculite or zeolite as a supplement. The recommended formulation, i.e. an improved formulation of the cemented ash waste form is that additives DH 4A flow promoter and vermiculite (or zeolite) are added on the ground of optimum cement/ash/water formulation of the cemented waste form, the dosage of water, DH 4A and vermiculite (or zeolite) is 70 wt%, 0.5 wt% and ≤ 5 wt% of the cement dosage, respectively. The cemented ash waste forms obtained meet all the requirements for disposal. (author). 12 refs, 7 figs, 13 tabs

  9. Standardization of spray-dried powder of Piper betle hot water extract

    Science.gov (United States)

    Arawwawala, Liyanage Dona Ashanthi Menuka; Hewageegana, Horadugoda Gamage Sujatha Pushpakanthi; Arambewela, Lakshmi Sriyani Rajapaksha; Ariyawansa, Hettiarachchige Sami

    2011-01-01

    The leaves of Piper betle Linn. (Family: Piperaceae) possess several bioactivities and are used in the Traditional Medical systems of Sri Lanka. The present investigation was carried out to standardize the spray-dried powder of P. betle by (a) determination of physicochemical parameters, presence or absence of heavy metals, and microbial contamination; (b) screening for phytochemicals; and (c) development of High Pressure Liquid Chromatography (HPLC) fingerprint and densitogram. The percentages of moisture content, total ash, acid insoluble ash, water-soluble ash, and ethanol extractable matter of spray-dried powder of P. betle were 2.2-2.5, 6.8-7.0, 0.003-0.005, 4.1-4.3, and 15.8-16.2, respectively. The concentrations of all the tested heavy metals were below the WHO acceptable limits and bacterial species, such as Escherichia coli, Salmonella spp, Staphylococcus aureus, and Pseudomonas aeroginosa were not present in the P. betle spray-dried powder. Phenolic compounds, tannins, flavonoids steroids, and alkaloids were found to be present in the spray-dried powder of P. betle and HPLC fingerprint and densitogram clearly demonstrated the proportional differences of these chemical constituents. In conclusion, the results obtained from this study can be used to standardize the spray-dried powder of P. betle. PMID:21716924

  10. Standardization of spray-dried powder of Piper betle hot water extract.

    Science.gov (United States)

    Arawwawala, Liyanage Dona Ashanthi Menuka; Hewageegana, Horadugoda Gamage Sujatha Pushpakanthi; Arambewela, Lakshmi Sriyani Rajapaksha; Ariyawansa, Hettiarachchige Sami

    2011-04-01

    The leaves of Piper betle Linn. (Family: Piperaceae) possess several bioactivities and are used in the Traditional Medical systems of Sri Lanka. The present investigation was carried out to standardize the spray-dried powder of P. betle by (a) determination of physicochemical parameters, presence or absence of heavy metals, and microbial contamination; (b) screening for phytochemicals; and (c) development of High Pressure Liquid Chromatography (HPLC) fingerprint and densitogram. The percentages of moisture content, total ash, acid insoluble ash, water-soluble ash, and ethanol extractable matter of spray-dried powder of P. betle were 2.2-2.5, 6.8-7.0, 0.003-0.005, 4.1-4.3, and 15.8-16.2, respectively. The concentrations of all the tested heavy metals were below the WHO acceptable limits and bacterial species, such as Escherichia coli, Salmonella spp, Staphylococcus aureus, and Pseudomonas aeroginosa were not present in the P. betle spray-dried powder. Phenolic compounds, tannins, flavonoids steroids, and alkaloids were found to be present in the spray-dried powder of P. betle and HPLC fingerprint and densitogram clearly demonstrated the proportional differences of these chemical constituents. In conclusion, the results obtained from this study can be used to standardize the spray-dried powder of P. betle.

  11. Ash fusion temperatures and their association with the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.K.; Wall, T.F.; Gupta, R.P. [Cooperative Research Centre for Black Coal Utilisation, Newcastle, NSW (Australia); Creelman, R.A. [Creelman (R.A.) and Associates, Sydney, NSW (Australia)

    1997-04-01

    Ash deposition on furnace walls in PF (pulverized fuel) furnaces is called slagging when it occurs in the high temperature areas of furnaces directly exposed to flame radiation and fouling in other regions such as tubes in the convection section of the boiler. There are well documented shortcomings of certain approaches relating to their uncertainties as predictive tools for plant performance such as poor repeatability and re-producibility of ash fusion measurements. The nature of physical and chemical changes occurring during melting of coal ash has been investigated in the current study to provide an alternative procedure to the ash fusion test. Shrinkage measurements are frequently used in metallurgy and ceramic science to study the physical properties of materials at high temperatures. The output of this experiment provides three to four `peaks` (maximum rate of shrinkage with temperature) of different intensity and at different temperatures which are related to melting characteristics of the sample. It was concluded that shrinkage extents exceeding 50 percent indicated that the effect of the ash particle size is of secondary importance compared to ash chemistry in determining shrinkage levels, with fine particles giving rapid shrinkage events 10 degrees C lower in temperature. (author). 7 figs., refs.

  12. Glass-ceramic from mixtures of bottom ash and fly ash.

    Science.gov (United States)

    Vu, Dinh Hieu; Wang, Kuen-Sheng; Chen, Jung-Hsing; Nam, Bui Xuan; Bac, Bui Hoang

    2012-12-01

    Along with the gradually increasing yield of the residues, appropriate management and treatment of the residues have become an urgent environmental protection problem. This work investigated the preparation of a glass-ceramic from a mixture of bottom ash and fly ash by petrurgic method. The nucleation and crystallization kinetics of the new glass-ceramic can be obtained by melting the mixture of 80% bottom ash and 20% fly ash at 950 °C, which was then cooled in the furnace for 1h. Major minerals forming in the glass-ceramics mainly are gehlenite (Ca(2)Al(2)SiO(7)) & akermanite (Ca(2)MgSiO(7)) and wollastonite (CaSiO(3)). In addition, regarding chemical/mechanical properties, the chemical resistance showing durability, and the leaching concentration of heavy metals confirmed the possibility of engineering and construction applications of the most superior glass-ceramic product. Finally, petrurgic method of a mixture of bottom ash and fly ash at 950 °C represents a simple, inexpensive, and energy saving method compared with the conventional heat treatment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Cast-concrete products made with FBC ash and wet-collected coal-ash

    Energy Technology Data Exchange (ETDEWEB)

    Naik, T.R.; Kraus, R.N.; Chun, Y.M.; Botha, F.D. [University of Wisconsin, Milwaukee, WI (United States)

    2005-12-01

    Cast-concrete hollow blocks, solid blocks, and paving stones were produced at a manufacturing plant by replacing up to 45% (by mass) of portland cement with fluidized bed combustion (FBC) coal ash and up to 9% of natural aggregates with wet-collected, low-lime, coarse coal-ash (WA). Cast-concrete product specimens of all three types exceeded the compressive strength requirements of ASTM from early ages, with the exception of one paving-stone mixture, which fell short of the requirement by less than 10%. The cast-concrete products made by replacing up to 40% of cement with FBC ash were equivalent in strength (89-113% of control) to the products without ash. The abrasion resistance of paving stones was equivalent for up to 34% FBC ash content. Partial replacement of aggregates with WA decreased strength of the products. The resistance of hollow blocks and paving stones to freezing and thawing decreased appreciably with increasing ash contents. The cast-concrete products could be used indoors in regions where freezing and thawing is a concern, and outdoors in a moderate climate.

  14. Nutrient supply to reed canary grass as a bioenergy crop. Intercropping and fertilization with ash or sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lindvall, Eva

    2012-07-01

    Production of renewable energy from herbaceous crops on agricultural land is of great interest since fossil fuels need to be replaced with sustainable energy sources. Reed canary grass (RCG), Phalaris arundinacea L. is an interesting species for this purpose. The aim of this thesis was to study different approaches to reduce the requirement of mineral fertilizers in RCG production for bioenergy purposes. Paper I describes a study where fertilization effects and risk of heavy metal enrichment were studied, using annual applications of ash for seven years. Ash from co-combustion of RCG and municipal wastes (mixed ash), pure RCG ash and commercial fertilizers were compared. The experiment was harvested each spring. Paper II describes an ongoing study in which the effects of intercropping RCG in mixture with nitrogen-fixing perennial legumes are examined in two experiments, in combination with various fertilization treatments. Three fertilization treatments were applied: high N, low N (half of the high N) and low N + RCG ash/sewage sludge. A delayed harvest method was used; cutting the biomass in late autumn and harvesting in spring. Besides dry matter yield, the N-fixation rate was estimated. The results from paper I showed no differences between treatments in the dry matter yields or in the heavy metal concentrations in the biomass. Soil samples, taken when the experiment was finished, showed differences between treatments for Cd, Pb and Zn only in the uppermost soil level, highest levels for the mixed ash treatment. The results in paper II showed that at one site the legume proportion in the mixtures was low and did not affect RCG growth negatively. The high N treatment gave a higher spring yield than the low N treatments. Mean rates of N2-fixation in the first production year were 12-28, 33-40 and 55 kg N ha-1 kg for goat's rue (Galega orientalis Lam.), red clover (Trifolium pratense L.), and alsike clover (Trifolium hybridum L.), plots, respectively. At the

  15. Relation of ash composition to the uses of coal

    Energy Technology Data Exchange (ETDEWEB)

    Fieldner, A C; Selvig, W A

    1926-02-01

    The effects of coal ash and ash components on the utilization of coal for coke and gas production, steam generation, water gas production, smithing, and domestic uses were described in a review of literature. Calcite, gypsum, and pyrite which occur in high amounts in coal, increase the ash fusibility of the coal and render it unsuitable for many industrial and domestic uses. As a rule, coal ash of high Si content and low Fe content would not be readily fusible. High amounts of ash in coal also have the effect of reducing the heating value of the coal.

  16. Plutonium dissolution from Rocky Flats Plant incinerator ash

    International Nuclear Information System (INIS)

    Delegard, C.H.

    1985-06-01

    Rockwell Hanford Operations (Rockwell) soon will commence recovery of plutonium from Rocky Flats Plant incinerator ash. In preparation for this processing, Rockwell undertook literature and laboratory studies to identify, select and optimize plutonium dissolution methods for treating the ash. Ash reburning, followed by dissolution in nitric acid containing calcium fluoride, was selected as the processing method for the ash. Recommended values of process parameters were identified. Using the selected process, 99.5% plutonium recovery was achieved, leaving about 12.7 wt % heel residue for an equal weight composite of the three ashes tested. 15 refs., 26 figs

  17. Analysis list: ash2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ash2 Larvae + dm3 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash2.1.tsv ...http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash2.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash2....10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/ash2.Larvae.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Larvae.gml ...

  18. Analysis list: Ash2l [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Ash2l Blood + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2l.1.tsv... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2l.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2...l.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Ash2l.Blood.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Blood.gml ...

  19. Future fly ash marketing; Flugaschevermarktung in der Zukunft

    Energy Technology Data Exchange (ETDEWEB)

    Mauder, R.; Hugot, A. [Evonik Power Minerals GmbH, Dinslaken (Germany)

    2008-07-01

    It can be assumed that the fly ash production volumes will undergo a marked increase over the next few years. The conditions of fly ash production will improve as a result of modern and refurbished power plants, yielding a positive effect on the quality of fly ashes. Other vital parameters of future fly ash marketing are fly ash logistics and the infrastructure of power plants. Basically, economic utilisation of the increased production volumes is possible; however, new and long-term strategies are necessary. (orig.)

  20. Rice Hull Ash and Silicic Acid as Adsorbents for Concentration of Bacteriocins†

    OpenAIRE

    Janes, M. E.; Nannapaneni, R.; Proctor, A.; Johnson, M. G.

    1998-01-01

    A model procedure has been developed for the rapid extraction of five bacteriocins (nisin, pediocin RS2, leucocin BC2, lactocin GI3, and enterocin CS1) from concentrated freeze-dried crude culture supernatants by adsorption onto acid or alkaline rice hull ash (RHA) or silicic acid (SA). Bacteriocins were adsorbed onto RHA or SA by a pH-dependent method and desorbed by decreasing the pH to 2.5 or 3.0 and heating at 90°C for 5 min. The maximum adsorption and optimal pH range for different bacte...

  1. Possibilities of municipal solid waste incinerator fly ash utilisation.

    Science.gov (United States)

    Hartmann, Silvie; Koval, Lukáš; Škrobánková, Hana; Matýsek, Dalibor; Winter, Franz; Purgar, Amon

    2015-08-01

    Properties of the waste treatment residual fly ash generated from municipal solid waste incinerator fly ash were investigated in this study. Six different mortar blends with the addition of the municipal solid waste incinerator fly ash were evaluated. The Portland cement replacement levels of the municipal solid waste incinerator fly ash used were 25%, 30% and 50%. Both, raw and washed municipal solid waste incinerator fly ash samples were examined. According to the mineralogical composition measurements, a 22.6% increase in the pozzolanic/hydraulic properties was observed for the washed municipal solid waste incinerator fly ash sample. The maximum replacement level of 25% for the washed municipal solid waste incinerator fly ash in mortar blends was established in order to preserve the compressive strength properties. Moreover, the leaching characteristics of the crushed mortar blend was analysed in order to examine the immobilisation of its hazardous contents. © The Author(s) 2015.

  2. Synthetic aggregates from combustion ashes using an innovative rotary kiln.

    Science.gov (United States)

    Wainwright, P J; Cresswell, D J

    2001-01-01

    This paper describes the use of a number of different combustion ashes to manufacture synthetic aggregates using an innovative rotary 'Trefoil' kiln. Three types of combustion ash were used, namely: incinerated sewage sludge ash (ISSA); municipal solid waste incinerator bottom ash (MSWIBA-- referred to here as BA); and pulverised fuel ash (Pfa). The fine waste ash fractions listed above were combined with a binder to create a plastic mix that was capable of being formed into 'green pellets'. These pellets were then fired in a Trefoil kiln to sinter the ashes into hard fused aggregates that were then tested for use as a replacement for the natural coarse aggregate in concrete. Results up to 28 days showed that these synthetic aggregates were capable of producing concretes with compressive strengths ranging from 33 to 51 MPa, equivalent to between 73 and 112% of that of the control concrete made with natural aggregates.

  3. Residual Ash Formation during Suspension-Firing of Biomass

    DEFF Research Database (Denmark)

    Damø, Anne Juul; Jappe Frandsen, Flemming; Jensen, Peter Arendt

    2014-01-01

    Through 50+ years, high quality research has been conducted in order to characterize ash and deposit formation in utility boilers fired with coal, biomass and waste fractions. The basic mechanism of fly ash formation in suspension fired coal boilers is well described, documented and may even...... be modeled relatively precisely. Concerning fly ash formation from biomass or waste fractions, the situation is not nearly as good. Lots of data are available from campaigns where different ash fractions, including sometimes also in-situ ash, have been collected and analyzed chemically and for particle size...... distribution. Thus, there is a good flair of the chemistry of fly ash formed in plants fired with biomass or waste fractions, either alone, or in conjunction with coal. But data on dedicated studies of the physical size development of fly ash, are almost non-existing for biomasses and waste fractions...

  4. Ash transformation during co-firing coal and straw

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Peter Arendt; Jensen, Anker Degn

    2007-01-01

    Co-firing straw with coal in pulverized fuel boilers can cause problems related to fly ash utilization, deposit formation, corrosion and SCR catalyst deactivation due to the high contents of Cl and K in the ash. To investigate the interaction between coal and straw ash and the effect of coal...... quality on fly ash and deposit properties, straw was co-fired with three kinds of coal in an entrained flow reactor. The compositions of the produced ashes were compared to the available literature data to find suitable scaling parameters that can be used to predict the composition of ash from straw...... and coal co-firing. Reasonable agreement in fly ash compositions regarding total K and fraction of water soluble K was obtained between co-firing in an entrained flow reactor and full-scale plants. Capture of potassium and subsequent release of HCl can be achieved by sulphation with SO2 and more...

  5. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Dry Eye ... Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es el ojo seco? Written By: Kierstan ...

  6. Dry eye syndrome

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000426.htm Dry eye syndrome To use the sharing features on this page, ... second-hand smoke exposure Cold or allergy medicines Dry eye can also be caused by: Heat or ... Symptoms may include: Blurred vision Burning, itching, ...

  7. Dry Mouth (Xerostomia)

    Science.gov (United States)

    ... mouth Trouble chewing, swallowing, tasting, or speaking A burning feeling in the mouth A dry feeling in the throat Cracked lips ... Food and Drug Administration provides information on dry mouth and offers advice for ... Syndrome Clinic NIDCR Sjogren’s Syndrome Clinic develops new therapies ...

  8. Evaluating energy efficient strategies and product quality for distillers' dried grains with solubles (DDGS) in dry-grind ethanol plants

    Science.gov (United States)

    Lan, Tian

    tested and the response variables were measured which included energy performance (specific power consumption, energy efficiency, drying efficiency, drying rate), physical properties [particle size distribution (PSD), geometric mean particle size (dwg), bulk density, tapped bulk density, true density, color, compressibility index (CI), Hausner ratio (HR)], and chemical properties [acid detergent fiber (ADF), neutral detergent fiber (NDF), oil, crude protein, starch, ash, etc]. The results of the bench-scale study were also compared with data from a previous plant-scale DDGS production process investigation that used similar drying strategies. Results from the experiments indicated that among all 16 drying strategies, the 10% CDS content and 60% DDGS add-back strategy achieved the least specific power consumption (SPC) while the 40% CDS content and 20% DDGS add-back strategy had the highest SPC. The energy efficiency and drying efficiency of the bench-scale data in both drying stage I and drying stage II presented similar trends as process parameters changed. The highest energy and drying efficiencies were achieved in strategies with 10% CDS content while the lowest were in strategies with 40% CDS content. A comparison of the energy and drying efficiencies for the bench-scale strategies conducted in this study with those of similar plant-scale strategies from a previous study showed a similar trend in the data for drying stage 1, even though the actual numbers were quite different for the two experimental scales. On average, the energy and drying efficiencies for the bench-scale study was 40% less than the corresponding plant-scale strategy. CDS content had the most influence on the energy performance during DDGS drying, while percent DDGS add-back had more impact on the SPC given a constant CDS content level. By comparing both the physical properties, bulk density in particular which relates to logistics, and energy performance data, the drying strategy with 20% CDS and

  9. Mapping ash properties using principal components analysis

    Science.gov (United States)

    Pereira, Paulo; Brevik, Eric; Cerda, Artemi; Ubeda, Xavier; Novara, Agata; Francos, Marcos; Rodrigo-Comino, Jesus; Bogunovic, Igor; Khaledian, Yones

    2017-04-01

    In post-fire environments ash has important benefits for soils, such as protection and source of nutrients, crucial for vegetation recuperation (Jordan et al., 2016; Pereira et al., 2015a; 2016a,b). The thickness and distribution of ash are fundamental aspects for soil protection (Cerdà and Doerr, 2008; Pereira et al., 2015b) and the severity at which was produced is important for the type and amount of elements that is released in soil solution (Bodi et al., 2014). Ash is very mobile material, and it is important were it will be deposited. Until the first rainfalls are is very mobile. After it, bind in the soil surface and is harder to erode. Mapping ash properties in the immediate period after fire is complex, since it is constantly moving (Pereira et al., 2015b). However, is an important task, since according the amount and type of ash produced we can identify the degree of soil protection and the nutrients that will be dissolved. The objective of this work is to apply to map ash properties (CaCO3, pH, and select extractable elements) using a principal component analysis (PCA) in the immediate period after the fire. Four days after the fire we established a grid in a 9x27 m area and took ash samples every 3 meters for a total of 40 sampling points (Pereira et al., 2017). The PCA identified 5 different factors. Factor 1 identified high loadings in electrical conductivity, calcium, and magnesium and negative with aluminum and iron, while Factor 3 had high positive loadings in total phosphorous and silica. Factor 3 showed high positive loadings in sodium and potassium, factor 4 high negative loadings in CaCO3 and pH, and factor 5 high loadings in sodium and potassium. The experimental variograms of the extracted factors showed that the Gaussian model was the most precise to model factor 1, the linear to model factor 2 and the wave hole effect to model factor 3, 4 and 5. The maps produced confirm the patternd observed in the experimental variograms. Factor 1 and 2

  10. Comparison of emerald ash borer preference for ash of different species, sun exposure, age, and stress treatments in relation to foliar volatiles and nutrition

    Science.gov (United States)

    Therese M. Poland; Deepa S. Pureswaran; Yigen Chen

    2009-01-01

    We investigated the host selection behavior and feeding preference of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) on six different species of ash including Manchurian ash (F...

  11. Application of paste technology to mitigate the dust emissions from handling of fly and bottom ash at coal fired power plant : CGTEE in Candiota, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Silva Marques, M.E. [Golder Associates Peru, Lima (Peru); Lima, H. [Golder Associates Brazil, Sao Paulo (Brazil); Mandl, B.; Francoeur, R.; Palkovits, F. [Golder Paste Technology Ltd., Mississauga, ON (Canada); Blois, R. [Companhia de Geracao Termica de Energia Electrica, Porto Alegre (Brazil)

    2010-07-01

    This paper discussed a method developed to reduce dust emissions generated in a fly ash handling procedure used at a thermal power plant located in the south of Brazil. The fly ash is collected in dry form at several locations in the plant and pneumatically conveyed to storage silos, where it is moistened with water in a mixer, loaded into dump trucks and deposited in a disposal area near a surface coal mine. The new solution created low density fly ash slurry in localized mixing tanks within the power plant. The low density slurry is pumped to an ash conditioning plant where the slurry is then mixed with the bottom ash, dewatered, and densified. The densified slurry is then pumped to an adjacent coal mine disposal site in order to be used as backfill in mined areas. The proposed method will significantly reduce dust emissions both inside and outside the plant, and will substantially reduce truck traffic at the mine. The method will reduce the environmental impacts associated with fly ash dust emissions in the region. 8 figs.

  12. Degradation rate of sludge/fly ash mixture used as landfill liner; Nedbrytningshastigheten foer taetskikt uppbyggda av slam och aska

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, Karin; Berg, Magnus [AaF-Process AB, Stockholm (Sweden); Svensson, Malin; Ecke, Holger [Luleaa Univ. of Technology (Sweden)

    2005-10-01

    In order to be able to use mixtures of ash and sludge as landfill liner an important aspect is to demonstrate that the degradation of organic matter is slow enough. Therefore, the goal of this project has been to find out for how long a landfill liner material of sludge and ash will be stable and keep its function. The degradation of organic material in two different mixtures of sludge and ash has been studied in laboratory experiments. The rate of degradation was then estimated for barriers of sludge and ash, taking into account construction techniques (mixture, compaction, water content), climate conditions (freezing, drying) and biological processes (NaN{sub 3} additive). The effect of the degradation on the permeability has also been quantified. Organic material may disappear for the landfill liner material through 1) initial leaching of soluble organic material, 2) leaching of organic material after chemical reactions or 3) evaporation during biological degradation. Bacterial activity was not found in the sludge/ash mixtures during the experiments. Therefore, the organic material is probably reduced mainly though leaching according to 1) and 2). The leached amount of TOC (total organic carbon) was measured for all samples of sludge/ash in several experimental cycles. The leached amount of TOC was compared to the initial amount of TOC in the material. The results show a small initial reduction of organic material through leaching but the TOC content in the material is then stabilized. In relation to the total weight of the material the leaching of TOC was similar for the mixtures with 80 % ash and 20 % ash. However, this means that a larger amount of TOC was leached out from the mixtures with a high ash content since the initial amount of organic material was smaller. General conclusions about which ash-sludge ratio that is suitable for a landfill liner material could not be drawn from the experiments from a degradation point of view. If the initial

  13. Drying grain using a hydrothermally treated liquid lignite fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bukurov, Z.; Cvijanovic, P.; Bukurov, M. [Univ. of Novi Sad (Yugoslavia); Ljubicic, B.R. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-01

    A shortage of domestic oil and natural gas resources in Yugoslavia, particularly for agricultural and industrial purposes, has motivated the authors to explore the possibility of using liquid lignite as an alternate fuel for drying grain. This paper presents a technical and economic assessment of the possibility of retrofitting grain-drying plants currently fueled by oil or natural gas to liquid lignite fuel. All estimates are based on lignite taken from the Kovin deposit. Proposed technology includes underwater mining techniques, aqueous ash removal, hydrothermal processing, solids concentration, pipeline transport up to 120 km, and liquid lignite direct combustion. For the characterization of Kovin lignite, standard ASTM procedures were used: proximate, ultimate, ash, heating value, and Theological analyses were performed. Results from an extensive economic analysis indicate a delivered cost of US$20/ton for the liquid lignite. For the 70 of the grain-drying plants in the province of Vojvodina, this would mean a total yearly saving of about US $2,500,000. The advantages of this concept are obvious: easy to transport and store, nonflammable, nonexplosive, nontoxic, 30%-40% cheaper than imported oil and gas, domestic fuel is at hand. The authors believe that liquid lignite, rather than an alternative, is becoming more and more an imperative.

  14. Norm in coal, fly ash and cement

    International Nuclear Information System (INIS)

    Kant, K.; Upadhyay, S.B.; Sharma, G.S.

    2006-01-01

    Coal is technologically important materials being used for power generation and its cinder (fly ash) is used in manufacturing of bricks, sheets, cement, land filling etc. 222 Rn (radon) and its daughters are the most important radioactive and potentially hazardous elements, which are released in the environment from the naturally occurring radioactive material (NORM) present in coal, fly ash and cement. Thus it is very important to carry out radioactivity measurements in coal, fly ash and cement from the health and hygiene point of view. Samples of coal and fly ash from different thermal power stations in northern India and various fly ash using establishments and commercially available cement samples (O.P.C. and P.P.C.) were collected and analyzed for radon concentration and exhalation rates. For the measurements, alpha sensitive LR-115 type II plastic track detectors were used. The radon concentration varied from 147 Bq/m 3 to 443 Bq/m 3 , the radium concentration varied from 1.5 to 4.5 Bq/kg and radon exhalation rate varied from 11.8 mBq.kg -1 .h -1 to 35.7 mBq.kg -1 .h -1 for mass exhalation rate and from 104.5 mBq.m -2 .h -1 to 314.8 mBq.m -2 .h -1 for surface exhalation rate in coal samples. The radon concentration varied from 214 Bq/m 3 to 590 Bq/m 3 , the radium concentration varied from 1.0 to 2.7 Bq/kg and radon exhalation rate varied from 7.8 mBq.kg -1 .h -1 to 21.6 mBq.kg -1 .h -1 for mass exhalation rate and from 138 mBq m -2 h -1 to 380.6 mBq.m -2 .h -1 for surface exhalation rate in fly ash samples. The radon concentration varied from 157.62 Bq/m 3 to 1810.48 Bq/m 3 , the radium concentration varied from 0.76 Bq/kg to 8.73 Bq/kg and radon exhalation rate varied from 6.07 mBq.kg -1 .hr -1 to 69.81 mBq.kg -1 .hr -1 for mass exhalation rate and from 107.10 mBq.m -2 .hr -1 to 1230.21 mBq.m -2 .hr -1 for surface exhalation rate in different cement samples. The values were found higher in P.P.C. samples than in O.P.C. samples. (authors)

  15. Elemental analysis of bottom ash from municipal incinerator by neutron activation analysis

    International Nuclear Information System (INIS)

    Kim, S. H.; Jang, S. H.; Moon, J. H.; Jung, Y. S.; Kim, Y. J.

    2003-01-01

    Elemental analysis of bottom ash generated from municipal solid waste incinerator was performed by neutron activation analysis. For this study, ash samples monthly collected from incinerator in D city were sieved with 5 mm mesh size, dried, pulverized by agate mortar and finally re-sieved with 200μ mesh size. Prepared samples were irradiated by neutrons using NAA No.1 irradiation hole in Korea Atomic Energy Research Institute. Activated samples were measured by gamma-ray spectrometer according to the relevant nuclear properties of target nuclides and the concentration of 33 elements were determined from the collected ash samples. Quality control was conducted by comparative analysis with two NIST standard reference materials simultaneously. Mean values and standard deviations of hazardous elements such as As, Cr, Cu, Fe, Mn, Sb and Zn among the determined elements were 3.8±6.9mg/kg, 620±0.12 %, 4.76±0.37 %, 0.26±0.10 %, 115±29 mg/kg and 0.71±0.19 %, respectively

  16. Using cement, lignite fly ash and baghouse filter waste for solidification of chromium electroplating treatment sludge

    Directory of Open Access Journals (Sweden)

    Wantawin, C.

    2004-02-01

    Full Text Available The objective of the study is to use baghouse filter waste as a binder mixed with cement and lignite fly ash to solidify sludge from chromium electroplating wastewater treatment. To save cost of solidification, reducing cement in binder and increasing sludge in the cube were focused on. Minimum percent cement in binder of 20 for solidification of chromium sludge was found when controlling lignite fly ash to baghouse filter waste at the ratio of 30:70, sludge to binder ratio of 0.5, water to mixer ratio of 0.3 and curing time of 7 days. Increase of sludge to binder ratio from 0.5 to 0.75 and 1 resulted in increase in the minimum percent cement in binder up to 30 percent in both ratios. With the minimum percent cement in binder, the calculated cement to sludge ratios for samples with sludge to binder ratios of 0.5, 0.75 and 1 were 0.4, 0.4 and 0.3 respectively. Leaching chromium and compressive strength of the samples with these ratios could achieve the solidified waste standard by the Ministry of Industry. For solidification of chromium sludge at sludge to binder ratio of 1, the lowest cost binder ratio of cement to lignite fly ash and baghouse filter waste in this study was 30:21:49. The cost of binder in this ratio was 718 baht per ton dry sludge.

  17. Phosphorus leaching from soils amended with thermally gasified piggery waste ash

    DEFF Research Database (Denmark)

    Kuligowski, Ksawery; Poulsen, Tjalfe

    2009-01-01

    In regions with intensive livestock farming, thermal treatment for local energy extraction from the manure and export of the P rich ash as a fertilizer has gained interest. One of the main risks associated with P fertilizers is eutrophication of water bodies. In this study P and K mobility in ash...... from anaerobically digested, thermally gasified (GA) and incinerated (IA) piggery waste has been tested using water loads ranging from 0.1 to 200 ml g−1. Leaching of P from soil columns amended with GA was investigated for one P application rate (205 kg P ha−1 corresponding to 91 mg P kg−1 soil dry...... matter) as a function of precipitation rate (9.5 and 2.5 mm h−1), soil type (Jyndevad agricultural soil and sand), amount of time elapsed between ash amendment and onset of precipitation (0 and 5 weeks) and compared to leaching from soils amended with a commercial fertilizer (Na2HPO4). Water soluble P...

  18. Dry well cooling device

    International Nuclear Information System (INIS)

    Suzuki, Hiroyuki.

    1997-01-01

    A plurality of blowing ports with introduction units are disposed to a plurality of ducts in a dry well, and a cooling unit comprising a cooler, a blower and an isolating valve is disposed outside of the dry well. Cooling air and the atmosphere in the dry well are mixed to form a cooling gas and blown into the dry well to control the temperature. Since the cooling unit is disposed outside of the dry well, the maintenance of the cooling unit can be performed even during the plant operation. In addition, since dampers opened/closed depending on the temperature of the atmosphere are disposed to the introduction units for controlling the temperature of the cooling gas, the temperature of the atmosphere in the dry well can be set to a predetermined level rapidly. Since an axial flow blower is used as the blower of the cooling unit, it can be contained in a ventilation cylinder. Then, the atmosphere in the dry well flowing in the ventilation cylinder can be prevented from leaking to the outside. (N.H.)

  19. Effects of wood ash fertilization on forest floor greenhouse gas emissions and tree growth in nutrient poor drained peatland forests

    International Nuclear Information System (INIS)

    Ernfors, M.; Sikstroem, U.; Nilsson, M.; Klemedtsson, L.

    2010-01-01

    Wood ash (3.1, 3.3 or 6.6 tonnes dry weight ha -1 ) was used to fertilize two drained and forested peatland sites in southern Sweden. The sites were chosen to represent the Swedish peatlands that are most suitable for ash fertilization, with respect to stand growth response. The fluxes of carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) from the forest floor, measured using opaque static chambers, were monitored at both sites during 2004 and 2005 and at one of the sites during the period 1 October 2007-1 October 2008. No significant (p > 0.05) changes in forest floor greenhouse gas exchange were detected. The annual emissions of CO 2 from the sites varied between 6.4 and 15.4 tonnes ha -1 , while the CH 4 fluxes varied between 1.9 and 12.5 kg ha -1 . The emissions of N 2 O were negligible. Ash fertilization increased soil pH at a depth of 0-0.05 m by up to 0.9 units (p 2 ha -1 year -1 and 0.52 m 2 ha -1 year -1 , respectively). The stand biomass, which was calculated using tree biomass functions, was not significantly affected by the ash treatment. The groundwater levels during the 2008 growing season were lower in the high ash dose plots than in the corresponding control plots (p < 0.05), indicating increased evapotranspiration as a result of increased tree growth. The larger basal area increment and the lowered groundwater levels in the high ash dose plots suggest that fertilization promoted tree growth, while not affecting greenhouse gas emissions.

  20. Experience in a 6.2 MW{sub e} pressurized fluidized bed gasifier with high ash Indian coals

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, G.; Rajasekaran, A.; Periyakaruppan, V.; Krishnamoorthy, S. [Bharat Heavy Electricals Ltd., Tiruchirappalli (India)

    2006-07-01

    Bharat Heavy Electrical Limited has installed a 165 tons/day air-blown pressurized fluidized bed gasifier (PFBG) as an add-on to their 6.2 MW IGCC demonstration plant and has operated it for more than 4000 hours. Improvements in the gasifier refractory lining, ash extraction and cooling devices, air distribution and temperature measuring devices were incorporated to improve the reliability and performance. Coal with 30-42% ash and high calorific value in the range of 15-20 MJ/kg was used during these operations with crushed coal of 1-4 mm as well as -6 mm coal with fines. Tests were conducted at gasifier pressure of 0.3-1.0 MPa, fluidized bed temperature of 980-1050{sup o}C and at various fluidized velocities and air to steam ratios. Once through carbon conversion efficiency of 90%, cold gas efficiency of 69% and dry gas calorific value of 4.4-4.6 MJ/Nm{sup 3} were obtained. About 15% char in fly ash (with 40% ash coal) was established by TGA. Seal pot system was added for recyling fly ash from the first cyclone to enhance carbon conversion, other parameters and to reduce the char in fly ash to acceptable level. Trends and correlations were established for constituents of gas, carbon conversion efficiency, cold gas efficiency, calorific value of gas and gas yield. BHEL is currently working with a partner to install a 125 MW IGCC plant. The paper elaborates the schematic and constructional details of the PFBG, operating experience and performance. 3 refs., 9 figs.

  1. Characteristics of Timbers Dried Using Kiln Drying and Radio Frequency-Vacuum Drying Systems

    OpenAIRE

    Rabidin Zairul Amin; Seng Gan Kee; Wahab Mohd Jamil Abdul

    2017-01-01

    Heavy hardwoods are difficult-to-dry timbers as they are prone to checking and internal stresses when dried using a conventional kiln drying system. These timbers are usually dried naturally to reach 15% to 19% moisture content with an acceptable defects. Besides long drying time, timbers at these moisture contents are not suitable for indoor applications since they will further dry and causing, for example, jointing and lamination failures. Drying to a lower moisture content could only be ac...

  2. Ash and burn control through fishbones

    Energy Technology Data Exchange (ETDEWEB)

    Varadarajan, V.; Miley, G.H.

    1989-01-01

    The thermal alphas will accumulate in the center of the ignited thermonuclear plasma in the long pulse experiments. This accumulation increases the Z{sub eff} leading to increased synchrotron losses and decreases the effective fuel density which reduces the power output. Also the ignited plasma is burn-unstable and its temperature is expected to increase above the design point until a stable equilibrium is reached at a higher temperature. This higher operating temperature is not expected to be beneficial. Thus we are faced with the dual problem of ash accumulation and thermonuclear burn instability in the steadily burning tokamak plasma. So some means of controlling them is desirable. Several control schemes for both problems have been proposed. But it is felt that we need alternatives with more desirable characteristics. In this paper, we explore the use of fishbones' as possible scheme that will achieve the dual purpose of ash and burn control. 3 refs.

  3. Production of ceramics from coal fly ash

    Directory of Open Access Journals (Sweden)

    Angjusheva Biljana

    2012-01-01

    Full Text Available Dense ceramics are produced from fly ash from REK Bitola, Republic of Macedonia. Four types of fly ash from electro filters and one from the collected zone with particles < 0.063 mm were the subject of this research. Consolidation was achieved by pressing (P= 133 MPa and sintering (950, 1000, 1050 and 11000C and heating rates of 3 and 100/min. Densification was realized by liquid phase sintering and solid state reaction where diopside [Ca(Mg,Al(Si,Al2O6] was formed. Ceramics with optimal properties (porosity 2.96±0.5%, bending strength - 47.01±2 MPa, compressive strength - 170 ±5 MPa was produced at 1100ºC using the heating rate of 10ºC/min.

  4. Fundamental study of low-NOx combustion fly ash utilization

    International Nuclear Information System (INIS)

    Suuberg, Eric M.; Hurt, Robert H.

    1998-01-01

    This study is principally concerned with characterizing the organic part of coal combustion fly ashes. High carbon fly ashes are becoming more common as by-products of low-NOx combustion technology, and there is need to learn more about this fraction of the fly ash. The project team consists of two universities, Brown and Princeton, and an electrical utility, New England Power. A sample suite of over fifty fly ashes has been gathered from utilities across the United States, and includes ashes from a coals ranging in rank from bituminous to lignite. The characterizations of these ashes include standard tests (LOI, Foam Index), as well as more detailed characterizations of their surface areas, porosity, extractability and adsorption behavior. The ultimate goal is, by better characterizing the material, to enable broadening the range of applications for coal fly ash re-use beyond the current main market as a pozzolanic agent for concretes. The potential for high carbon-content fly ashes to substitute for activated carbons is receiving particular attention. The work performed to date has already revealed how very different the surfaces of different ashes produced by the same utility can be, with respect to polarity of the residual carbon. This can help explain the large variations in acceptability of these ashes as concrete additives

  5. Environmentally friendly use of non-coal ashes in Sweden.

    Science.gov (United States)

    Ribbing, C

    2007-01-01

    The Swedish Thermal Engineering Research Institute (Värmeforsk) initiated an applied research program "Environmentally friendly use of non-coal ashes", in 2002. The program aims at increasing knowledge on the by-products of energy production and their application. The goal of formulating technical and environmental guidelines and assessments is a major point of the program, which is supported by about forty authorities and private organisations. The programme has been divided into four areas: recycling of ashes to forests, geotechnical applications, use in landfilling, and environmental aspects and chemistry. Among all results obtained, the following progress is shown: *Evidence for the positive effects of spreading ashes on forest growth. *A proposal for environmental guidelines on the utilisation of ashes in construction. *A handbook for using non-coal fly ashes in unpaved roads. *Technical and environmental assessments of MSWI bottom ashes in road construction. *Development of the use of ashes with municipal wastewater sludge as a cover for landfills and mine tailings. *Use of ashes from bio-fuels in concrete and replacement of cement in stoop mining. *A method to classify those by-products from combustion that have mirror entries in the EWC as a hazardous or non-hazardous compound. The Ash Programme has also made it possible to increase knowledge on ashes as valuable materials, on quality assurance and on markets for recovered materials.

  6. Coal ash usage in environmental restoration at the Hanford site

    Energy Technology Data Exchange (ETDEWEB)

    Scanlon, P.L.; Sonnichsen, J.C.; Phillips, S.J.

    1994-08-01

    The ash stockpiled next to the 284E steam plant is mixed fly ash, bottom ash, and slag. The ash consists of (1) baghouse residue and (2) a mixture of bottom ash and slag which is washed out of the bottom of the boilers daily. In 1991, a Toxicity Characteristic Leaching Procedure (TCLP) was performed on several samples of this ash (Hazen Research 1991). This procedure is designed to determine the mobility of organic and inorganic anatytes present in liquid, solid, or multiphasic wastes (EPA 1994). The ash tested came from surge bins, conveyor samples, and bottom ash and fly ash from the boilers at 284E. Antimony, cadmium, germanium, molybdenum, silver, thallium, tungsten, and vanadium were tested for, but on all samples were below detection Limits for the testing method. Analytes present in relatively high concentrations (but less than one part per thousand) included barium, boron, chromium, fluorine, and zinc. The size of ash particles passing through a Taylor sieve series was very evenly distributed from 1 to 200m.

  7. Optimization of heat-liberating batches for ash residue stabilization

    International Nuclear Information System (INIS)

    Karlina, O.K.; Varlackova, G.A.; Ojovan, M.I.; Tivansky, V.M.; Dmitriev, S.A.

    1999-01-01

    The ash residue obtained after incineration of solid radioactive waste is a dusting poly-dispersed powder like material that contains radioactive nuclides ( 137 Cs, 90 Sr, 239 Pu, hor ( ellipsis)). Specific radioactivity of the ash can be about 10 5 --10 7 Bq/kg. In order to dispose of the ash, residue shall be stabilized by producing a monolith material. The ash residue can be either vitrified or stabilized into a ceramic matrix. For this purpose the ash residue is mixed with fluxing agents followed by melting of obtained composition in the different type melters. As a rule this requires both significant energy consumption and complex melting equipment. A stabilization technology of ash residue was proposed recently by using heat liberating batches-compositions with redox properties. The ash residue is melted due to exothermic chemical reactions in the mixture with heat-liberating batch that occur with considerable release of heat. Stabilization method has three stages: (1) preparation of a mixture of heating batch and ash residue with or without glass forming batch (frit); (2) ignition and combustion of mixed composition; (3) cooling (quenching) of obtained vitreous material. Combustion of mixed composition occurs in the form of propagation of reacting wave. The heat released during exothermic chemical reactions provides melting of ash residue components and production of glass-like phase. The final product consists of a glass like matrix with embedded crystalline inclusions of infusible ash residue components

  8. Cement Stabilized Soil Blocks Admixed with Sugarcane Bagasse Ash

    Directory of Open Access Journals (Sweden)

    Jijo James

    2016-01-01

    Full Text Available The study involved investigating the performance of ordinary Portland cement (OPC stabilized soil blocks amended with sugarcane bagasse ash (SBA. Locally available soil was tested for its properties and characterized as clay of medium plasticity. This soil was stabilized using 4% and 10% OPC for manufacture of blocks of size 19 cm × 9 cm × 9 cm. The blocks were admixed with 4%, 6%, and 8% SBA by weight of dry soil during casting, with plain OPC stabilized blocks acting as control. All blocks were cast to one target density and water content followed by moist curing for a period of 28 days. They were then subjected to compressive strength, water absorption, and efflorescence tests in accordance with Bureau of Indian standards (BIS specifications. The results of the tests indicated that OPC stabilization resulted in blocks that met the specifications of BIS. Addition of SBA increased the compressive strength of the blocks and slightly increased the water absorption but still met the standard requirement of BIS code. It is concluded that addition of SBA to OPC in stabilized block manufacture was capable of producing stabilized blocks at reduced OPC content that met the minimum required standards.

  9. Stoneware tile manufacturing using rice straw ash as feldspar replacement

    International Nuclear Information System (INIS)

    Alvaro Guzman, A.; John Torres, L.; Martha Cedeno, V.; Silvio Delvasto, A.; Vicente Amigo, B.; Enrique Sanchez, V.

    2013-01-01

    In this research are presented the results of using rice straw ash (RSA) in low proportions as substitute of feldspar for manufacturing stoneware tiles. Specimens of semidry triaxial mixtures, where feldspar was substituted for different percentages (25 % and 50 %) of RSA, were prepared by uniaxial pressing, followed by drying and sintering. Physical and mechanical properties of sintered bodies were evaluated. Porcelain stoneware tile specimens C0 and CF25 reached bending strength and water absorption values were in accordance with standard ISO 13006 (Annex G, BIa) ( ≥ 35 MPa and ≤ 0.5 %, respectively). However, in porcelain stoneware tile specimens CF50 due to bloating phenomenon was not possible obtain commercial tiles in accordance with standard ISO 13006. By using Scanning Electron Microscopy (SEM) needles of primary and secondary mullite were identified in a vitreous phase; and by using X-Ray Diffraction (XRD) mullite and quartz phases were identified. It was concluded that feldspar can be substituted positively by RSA in stoneware tile pastes. (Author)

  10. Radiochemical analysis of the Bikini ashes

    Energy Technology Data Exchange (ETDEWEB)

    Ishibashi, M; Shigematsu, T; Ishida, T

    1954-01-01

    The following nuclides were detected in the Bikini ashes by radiochemical procedures: /sup 45/Ca, /sup 89/Sr, /sup 91/Y, /sup 95/Zr, /sup 103/Ru, /sup 144/Pr, and /sup 237/U. The ion-exchange method was used for analysis of contaminated rain water which fell on the Kyoto area on May 16, 1954 from which the presence of /sup 89/Sr, /sup 95/Zr, and /sup 140/Ba, was detected. Rare earths seemed also to be present.

  11. Biological influence of ash from radioactive fish

    Energy Technology Data Exchange (ETDEWEB)

    Obo, F; Wakamatsu, C; Hiwatashi, Y; Tamari, T. Nakae, Y.; Tajima, D

    1955-01-01

    Bones of a radioactive fish were ashed, extracted with 10 per cent HCl, and the extraction was neutralized with 10 per cent NaOH to give a white precipitate suspended in H/sub 2/O. The suspension was fed to rabbits. Most of the radioactivity was excreted in the feces; a small portion was retained in the cecum. Internal radioactivity was highest in the bones.

  12. Utilisation of high carbon pulverised fuel ash

    OpenAIRE

    Mahmud, Maythem Naji

    2011-01-01

    Coal combustion by-products generated from coal-fired power plant and cause enormous problems for disposal unless a way can be found to utilize these by-products through resource recovery programs. The implementation of air act regulations to reduce NOx emission have resulted millions of tonnes of pulverised fuel ash (PFA) accumulated with high percentage of unburned carbon made it un-saleable for the cement industry. Moreover, alternative fuels such as biomass and import coals were suggested...

  13. What Is Dry Eye?

    Medline Plus

    Full Text Available ... seasonal allergens and dry eye Apr 27, 2015 Choosing Wisely When It Comes to Eye Care, Part ... Name: Member ID: * Phone Number: * Email: * Enter code: * Message: Thank you Your feedback has been sent.

  14. What Is Dry Eye?

    Medline Plus

    Full Text Available ... month dissolvable punctal plug be removed or pushed down the tear duct to insert a permanent punctal ... Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  15. Dry Skin Relief

    Science.gov (United States)

    ... on a budget Skin care products Skin care secrets Skin lighteners Skin of color Summer skin problems ... condition, such as eczema. Additional related information Dermatologists' top tips for relieving dry skin FIND A DERMATOLOGIST ...

  16. Dry process potentials

    International Nuclear Information System (INIS)

    Faugeras, P.

    1997-01-01

    Various dry processes have been studied and more or less developed in order particularly to reduce the waste quantities but none of them had replaced the PUREX process, for reasons departing to policy errors, un-appropriate demonstration examples or too late development, although realistic and efficient dry processes such as a fluoride selective volatility based processes have been demonstrated in France (CLOVIS, ATILA) and would be ten times cheaper than the PUREX process. Dry processes could regain interest in case of a nuclear revival (following global warming fears) or thermal wastes over-production. In the near future, dry processes could be introduced in complement to the PUREX process, especially at the end of the process cycle, for a more efficient recycling and safer storage (inactivation)

  17. Freeze drying method

    International Nuclear Information System (INIS)

    Coppa, N.V.; Stewart, P.; Renzi, E.

    1999-01-01

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser

  18. What Is Dry Eye?

    Medline Plus

    Full Text Available ... removed or pushed down the tear duct to insert a permanent punctal plug? Sep 12, 2017 Why ... Eye from Jennifer Aniston Sep 02, 2016 The link between seasonal allergens and dry eye Apr 27, ...

  19. Cold Vacuum Drying Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Located near the K-Basins (see K-Basins link) in Hanford's 100 Area is a facility called the Cold Vacuum Drying Facility (CVDF).Between 2000 and 2004, workers at the...

  20. Pediatric deep burns caused by hot incense ashes during 2014 Spring Festival in Fuyang city, China.

    Science.gov (United States)

    Wang, Jian; Zhou, Bo; Tao, Ren Qin; Chen, Xu Lin

    2016-01-01

    The Chinese people in Fuyang city, a northwest city of Anhui Province, are accustomed to burning incense at home for blessing during the Spring Festival. Their children, especially toddlers, like playing around the burning incense and are at risk of burning by hot incense ashes. The purpose of this study was to describe the unique cause and clinical characteristics of pediatric deep burns caused by hot incense ashes during 2014 Spring Festival. Twelve consecutive children admitted to our Burn Center and Fuyang People's Hospital during 2014 Spring Festival, with burn injuries caused by hot incense ashes which were epidemiologically studied retrospectively. Data on age, gender, size, depth and site of burn, incidence by day, number of operation, hospital stay, and causes of burns were collected. All patients came from Fuyang city. Of the 12 patients, the average age was 2.17 years, with a range of 1-6. The boy-to-girl ratio was 2: 1. The mean total burn surface area (TBSA) was 5.83%, and 91.67% of the children sustained full-thickness burn. Hands were the most common parts of the body to be injured. Dry necrosis developed in 14 fingers of 3 patients. January 31, 2014, the first day of the Chinese New Year, was the time of highest incidence. Six patients (50%) required surgical intervention while the number of operations including escharectomy, excision, skin grafting, or amputation of necrotic fingers, per patient was 2. A total of 14 fingers were amputated of the necrotic parts. All children survived and mean length of hospital stay of the patients was 20 days. Hot incense ashes cause serious injuries to children in Fuyang city during the Spring Festival. Preventive programs should be directed towards high risk groups to reduce the incidence of this burn.

  1. Characterisation of chloride transport and reinforcement corrosion in concrete under cyclic wetting and drying by electrical resistivity

    NARCIS (Netherlands)

    Polder, R.B.; Peelen, W.H.A.

    2002-01-01

    Concrete prisms were made with four cement types including cements with fly ash and/or blast furnace slag and three waterto- cement (w/c) ratios. Chloride penetration and corrosion of rebars were stimulated by subjecting prisms to cyclic loading with salt solution and drying. Concrete resistivity,

  2. Review of Ecosystem Level Impacts of Emerald Ash Borer on Black Ash Wetlands: What Does the Future Hold?

    Directory of Open Access Journals (Sweden)

    Randall K. Kolka

    2018-04-01

    Full Text Available The emerald ash borer (EAB is rapidly spreading throughout eastern North America and devastating ecosystems where ash is a component tree. This rapid and sustained loss of ash trees has already resulted in ecological impacts on both terrestrial and aquatic ecosystems and is projected to be even more severe as EAB invades black ash-dominated wetlands of the western Great Lakes region. Using two companion studies that are simulating short- and long-term EAB infestations and what is known from the literature, we synthesize our current limited understanding and predict anticipated future impacts of EAB on black ash wetlands. A key response to the die-back of mature black ash will be higher water tables and the potential for flooding and resulting changes to both the vegetation and animal communities. Although seedling planting studies have shown some possible replacement species, little is known about how the removal of black ash from the canopy will affect non-ash species growth and regeneration. Because black ash litter is relatively high in nitrogen, it is expected that there will be important changes in nutrient and carbon cycling and subsequent rates of productivity and decomposition. Changes in hydrology and nutrient and carbon cycling will have cascading effects on the biological community which have been scarcely studied. Research to address these important gaps is currently underway and should lead to alternatives to mitigate the effects of EAB on black ash wetland forests and develop management options pre- and post-EAB invasion.

  3. Recirculation of biomass ashes onto forest soils: Ash composition, mineralogy and leaching properties

    DEFF Research Database (Denmark)

    Maresca, Alberto; Hyks, J.; Astrup, Thomas Fruergaard

    2017-01-01

    In Denmark, increasing amounts of wood ashes are generated from biomass combustion for energy production. The utilisation of ashes on top of forest soil for liming purposes has been proposed asan alternative to landfilling. Danish wood ash samples were collected and characterised with respect......, minor and trace elements were affected significantly by pH: high releases of PO4 3-, Mg, Zn, Cu and Cd were found for acidic conditions relevant to forest soils, while the highest releases of Mo and Cr were observed in alkaline conditions. Mineral phases were selected based on XRD analyses...... critical element compared with soil quality criteria, whereas the maximum theoretical loads of Ba, Cd, Cr, Sr, Mo, Ni, Pb, Sb, Se, Sn and V were relatively low....

  4. Crowdsourcing genomic analyses of ash and ash dieback – power to the people

    Directory of Open Access Journals (Sweden)

    MacLean Dan

    2013-02-01

    Full Text Available Abstract Ash dieback is a devastating fungal disease of ash trees that has swept across Europe and recently reached the UK. This emergent pathogen has received little study in the past and its effect threatens to overwhelm the ash population. In response to this we have produced some initial genomics datasets and taken the unusual step of releasing them to the scientific community for analysis without first performing our own. In this manner we hope to ‘crowdsource’ analyses and bring the expertise of the community to bear on this problem as quickly as possible. Our data has been released through our website at oadb.tsl.ac.uk and a public GitHub repository.

  5. High temperature co-treatment of bottom ash and stabilized fly ashes from waste incineration

    DEFF Research Database (Denmark)

    Sørensen, Mette Abildgaard; Mogensen, E.P.B.; Lundtorp, Kasper

    2001-01-01

    Bottom ashes from two Danish municipal solid waste incineration plants were heated at 900 degreesC with iron oxide stabilized air pollution control residues at actual mass flow ratios (9:1), simulating a treating method for the residues. The two residues were cotreated, producing one combined...... ashes. The process, thus, fixates the metals in the solid residues without altering the leaching properties of the bottom ash too significantly. (C) 2001 Elsevier Science Ltd. All rights reserved....... stream that may be utilized as a secondary road construction material. Scanning electron microscope analysis and grain size distribution analysis indicated that sintering of the particles did not occur. Batch leaching tests at liquid/solid 10 I/kg at a range of pH-values (6-10) quantified with respect...

  6. Three-year progression of emerald ash borer-induced decline and mortality in southeastern Michigan

    Science.gov (United States)

    Kamal J.K. Gandhi; Annemarie Smith; Robert P. Long; Robin A.J. Taylor; Daniel A. Herms

    2008-01-01

    We monitored the progression of ash (Fraxinus spp.) decline and mortality due to emerald ash borer (EAB), Agrilus planipennis, in 38 forest stands in the upper Huron River watershed region of southeastern Michigan from 2004-2007. Black ash (F. nigra), green ash (F. pennsylvanica), and white ash...

  7. Genetic transformation of Fraxinus spp. for resistance to the emerald ash borer

    Science.gov (United States)

    Paula M. Pijut; Rochelle R. Beasley; Kaitlin J. Palla

    2010-01-01

    The emerald ash borer (EAB; Agrilus planipennis Fairmaire) (Coleoptera; Buprestidae) is a wood-boring beetle that poses substantial risk to the ash resource in North America. Ash species native to the United States and known to be susceptible to EAB are Fraxinus pennsylvanica (green ash), F. americana (white ash...

  8. Effect of aggregate structure on VOC gas adsorption onto volcanic ash soil.

    Science.gov (United States)

    Hamamoto, Shoichiro; Seki, Katsutoshi; Miyazaki, Tsuyoshi

    2009-07-15

    The understanding of the gaseous adsorption process and the parameters of volatile organic compounds such as organic solvents or fuels onto soils is very important in the analysis of the transport or fate of these chemicals in soils. Batch adsorption experiments with six different treatments were conducted to determine the adsorption of isohexane, a gaseous aliphatic, onto volcanic ash soil (Tachikawa loam). The measured gas adsorption coefficient for samples of Tachikawa loam used in the first three treatments, Control, AD (aggregate destroyed), and AD-OMR (aggregate destroyed and organic matter removed), implied that the aggregate structure of volcanic ash soil as well as organic matter strongly enhanced gas adsorption under the dry condition, whereas under the wet condition, the aggregate structure played an important role in gas adsorption regardless of the insolubility of isohexane. In the gas adsorption experiments for the last three treatments, soils were sieved in different sizes of mesh and were separated into three different aggregate or particle size fractions (2.0-1.0mm, 1.0-0.5mm, and less than 0.5mm). Tachikawa loam with a larger size fraction showed higher gas adsorption coefficient, suggesting the higher contributions of macroaggregates to isohexane gas adsorption under dry and wet conditions.

  9. Removal of fluoride from drinking water using a modified fly ash adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Debasis Goswami; Arabinda K. Das

    2006-01-15

    Fly ash from a coal-fired power station was chemically modified and utilized for the removal of fluoride from drinking water. Two types of beds were used. Bed I was prepared by treatment with 12M HCl followed by neutralization with 5M NaOH solution. The reaction mass was filtered, washed, dried, and crushed to fine powder. Bed I material was mixed with alum and MgCl{sub 2} solutions and treated with 0.9M Na{sub 2}CO{sub 3} until pH reached to 4.5. Mass was again filtered, washed, dried at 120{sup o}C for 4 h and crushed to fine powder. This bed material is Bed II, which was used for defluoridation. Bed I was used to maintain pH (7.5-8.5) of the final effluent. Fluoride (100 ppm) present in both synthetic mixtures and drinking water samples was allowed to pass through Bed II (15 g) absorbent and effluents were found to contain no fluoride but pH of the effluent was 5.4-5.5. To maintain WHO guidelines for drinking water on pH, this effluent was again passed through Bed I. The effectiveness of the modified fly ash bed was satisfactory.

  10. Acidolysis of coal fly ash by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Torma, A.E.; Singh, A.K. (EG and G Idaho Inc., Idaho Falls, ID (United States). Center for Biological Processing Technology)

    1993-12-01

    The kinetics of aluminium extraction were investigated, using as-received and calcined fly ash samples and a pure culture of [ital Aspergillus niger]. This fungus metabolized sucrose to citric and oxalic acids, which were involved in the acidolysis of fly ash. Aluminium extraction from as-received fly ash was only 5-8%, whereas from calcined fly ash it was up to 93.5%. The order of reaction and the overall reaction rate constant were determined by the van't Hoff technique with respect to the concentration of calcined fly ash. A linearized form of a modified Monod expression was applied to the experimental data to assess the kinetic constants for the acidolysis process. Statistically designed experiments were carried out with calcined fly ash and synthetic solutions containing citric and oxalic acids to determine the optimum leaching conditions. The acidolysis reaction mechanism is discussed. 28 refs., 6 figs., 3 tabs.

  11. Wood ash as a soil additive and liming agent

    International Nuclear Information System (INIS)

    Campbell, A.; Etiegni, L.; Mahler, R.L.

    1991-01-01

    This study evaluated wood ash as an agricultural soil supplement and liming material. Winter wheat (Triticum aestivum) and poplar (Populus sp.) were grown in a greenhouse on six different Idaho soils amended with different ash concentrations. At ash levels equal to or lower than 2%, no detrimental effects were observed. In fact, the biomass of the wheat and the caliper and height of the poplar cuttings increased more at 2% ash 940 metric tons/ha than with the control soil. These results suggest that wood ash could be used in agricultural applications as a low analysis fertilizer containing potassium and as a liming agent. Land application of wood ash could be less expensive and more environmentally sound than present landfilling practices

  12. Physico-chemical characterisation of Indian biomass ashes

    Energy Technology Data Exchange (ETDEWEB)

    K. Umamaheswaran; Vidya S. Batra [Energy and Resources Institute (TERI), New Delhi (India)

    2008-05-15

    India stands fourth in biomass utilisation for various purposes like domestic, commercial and industrial applications. While extensive studies have been made for coal ash characterisation and utilisation, studies on characterisation of biomass ash and its utilisation has not been addressed. In this paper, biomass ash from five sources i.e. rice husk, bagasse, groundnut shell, cashewnut shell, and arecanut shell have been characterised. Chemical composition analysis, particle size analysis, thermal analysis, and microstructure analysis were carried out. Results show that in all ashes silica is the major compound with particle size ranging from 15 to 30 {mu}m and having irregular shape. Ash powders originating from cashewnut shell, arecanut shell and groundnut shell also have compounds of calcium, magnesium and potassium. Bagasse and cashewnut shell ashes have high LOI due to presence of unburnt carbon, P{sub 2}O{sub 5} and other volatiles. 16 refs., 22 figs., 3 tabs.

  13. Biofuel Combustion Fly Ash Influence on the Properties of Concrete

    Directory of Open Access Journals (Sweden)

    Aurelijus Daugėla

    2016-02-01

    Full Text Available Cement as the binding agent in the production of concrete can be replaced with active mineral admixtures. Biofuel combustion fly ash is one of such admixtures. Materials used for the study: Portland cement CEM I 42.5 R, sand of 0/4 fraction, gravel of 4/16 fraction, biofuel fly ash, superplasticizer, water. Six compositions of concrete were designed by replacing 0%, 5%, 10%, 15% 20%, and 25% of cement with biofuel fly ash. The article analyses the effect of biofuel fly ash content on the properties of concrete. The tests revealed that the increase of biofuel fly ash content up to 20% increases concrete density and compressive strength after 7 and 28 days of curing and decreases water absorption, with corrected water content by using plasticizing admixture. It was found that concrete where 20% of cement is replaced by biofuel ash has higher frost resistance.

  14. Changes of the soil environment affected by fly ash dumping site of the electric power plant

    Science.gov (United States)

    Weber, Jerzy; Gwizdz, Marta; Jamroz, Elzbieta; Debicka, Magdalena; Kocowicz, Andrzej

    2014-05-01

    In this study the effect of fly ash dumping site of the electric power plant on the surrounding soil environment was investigated. The fly ash dumping site collect wastes form brown coal combustion of Belchatow electric power station, central Poland. The dumping site is surrounding by forest, where pine trees overgrow Podzols derived from loose quartz sands. The soil profiles under study were located at a distance of 50, 100, 400 and 500 m from the dumping site, while control profiles were located 8 km away from the landfill. In all horizons of soil profiles the mpain hysico-chemical and chemical properties were determined. The humic substances were extracted from ectohumus horizons by Shnitzer's method, purified using XAD resin and freeze-dried. The fulvic acids were passed through a cation exchange column and freeze-dried. Optical density, elemental composition and atomic ratios were determined in the humic and fulvic acids. Organic carbon by KMnO4 oxidation was also determined in the organic soil horizons. The fly ash from the landfill characterized by high salinity and strong alkaline reaction (pH=10), which contributed significantly to the changes of the pH values in soils horizons. The alkalization of soils adjacent to the landfill was found, which manifested in increasing of pH values in the upper soil horizons. The impact of the landfill was also noted in the changes of the soil morphology of Podzols analysed. As a result of the alkalization, Bhs horizons have been converted into a Bs horizons. Leaching of low molecular humus fraction - typical for podzolization - has been minimized as a result of pH changes caused by the impact of the landfill, and originally occurring humic substances in the Bhs horizon (present in the control profiles) have been probably transported out of the soil profile and then into the groundwater.

  15. Utilization of ash from municipal solid waste combustion

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.; Hahn, J.; Magee, B.; Yuen, N.; Sandefur, K.; Tom, J.; Yap, C.

    1999-09-01

    This ash study investigated the beneficial use of municipal waste combustion combined ash from the H-POWER facility in Oahu. These uses were grouped into intermediate cover for final closure of the Waipahu landfill, daily cover at the Waimanalo Gulch Landfill, and partial replacement for aggregate in asphalt for road paving. All proposed uses examine combined fly and bottom ash from a modern waste-to-energy facility that meets requirements of the Clean Air Act Amendments for Maximum Achievable Control Technology.

  16. Removal mechanism of phosphate from aqueous solution by fly ash.

    Science.gov (United States)

    Lu, S G; Bai, S Q; Zhu, L; Shan, H D

    2009-01-15

    This work studied the effectiveness of fly ash in removing phosphate from aqueous solution and its related removal mechanism. The adsorption and precipitation of phosphate by fly ash were investigated separately in order to evaluate their role in the removal of phosphate. Results showed that the removal of phosphate by fly ash was rapid. The removal percentage of phosphate in the first 5min reached 68-96% of the maximum removal of phosphate by fly ash. The removal processes of phosphate by fly ash included a fast and large removal representing precipitation, then a slower and longer removal due to adsorption. The adsorption of phosphate on fly ash could be described well by Freundlich isotherm equation. The pH and Ca2+ concentration of fly ash suspension were decreased with the addition of phosphate, which suggests that calcium phosphate precipitation is a major mechanism of the phosphate removal. Comparison of the relative contribution of the adsorption and precipitation to the total removal of phosphate by fly ash showed that the adsorption accounted for 30-34% of the total removal of phosphate, depending on the content of CaO in fly ash. XRD patterns of the fly ash before and after phosphate adsorption revealed that phosphate salt (CaHPO4 x 2H2O) was formed in the adsorption process. Therefore, the removal of phosphate by fly ash can be attributed to the formation of phosphate precipitation as a brushite and the adsorption on hydroxylated oxides. The results suggested that the use of fly ash could be a promising solution to the removal of phosphate in the wastewater treatment and pollution control.

  17. Ash accumulation effects using bench marked 0-D model

    International Nuclear Information System (INIS)

    Hu, S.C.; Guo, J.P.; Miley, G.H.

    1990-01-01

    Ash accumulation is a key issue relative to our ability to achieve D- 3 He ARIES III burn conditions. 1-1/2-d transport simulations using the BALDUR code have been used to examine the correlation between the global ash particle confinement time and the edge exhaust (or recycling) efficiency. This provides a way to benchmark the widely used 0-D model. The burn conditions for an ARIES-III plasma with various ash edge recycling coefficients are examined

  18. Recovery of aluminum and other metal values from fly ash

    Science.gov (United States)

    McDowell, W.J.; Seeley, F.G.

    1979-11-01

    The invention relates to a method for improving the acid leachability of aluminum and other metal values found in fly ash which comprises sintering the fly ash, prior to acid leaching, with a calcium sulfate-containing composition at a temperature at which the calcium sulfate is retained in said composition during sintering and for a time sufficient to quantitatively convert the aluminum in said fly ash into an acid-leachable form.

  19. Improved prediction and tracking of volcanic ash clouds

    Science.gov (United States)

    Mastin, Larry G.; Webley, Peter

    2009-01-01

    During the past 30??years, more than 100 airplanes have inadvertently flown through clouds of volcanic ash from erupting volcanoes. Such encounters have caused millions of dollars in damage to the aircraft and have endangered the lives of tens of thousands of passengers. In a few severe cases, total engine failure resulted when ash was ingested into turbines and coating turbine blades. These incidents have prompted the establishment of cooperative efforts by the International Civil Aviation Organization and the volcanological community to provide rapid notification of eruptive activity, and to monitor and forecast the trajectories of ash clouds so that they can be avoided by air traffic. Ash-cloud properties such as plume height, ash concentration, and three-dimensional ash distribution have been monitored through non-conventional remote sensing techniques that are under active development. Forecasting the trajectories of ash clouds has required the development of volcanic ash transport and dispersion models that can calculate the path of an ash cloud over the scale of a continent or a hemisphere. Volcanological inputs to these models, such as plume height, mass eruption rate, eruption duration, ash distribution with altitude, and grain-size distribution, must be assigned in real time during an event, often with limited observations. Databases and protocols are currently being developed that allow for rapid assignment of such source parameters. In this paper, we summarize how an interdisciplinary working group on eruption source parameters has been instigating research to improve upon the current understanding of volcanic ash cloud characterization and predictions. Improved predictions of ash cloud movement and air fall will aid in making better hazard assessments for aviation and for public health and air quality. ?? 2008 Elsevier B.V.

  20. Ash chemistry and sintering, verification of the mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Skrifvars, B.J. [Aabo Akademi, Turku (Finland)

    1996-12-01

    In this project four sintering mechanisms have been studied, i.e., partial melting with a viscous liquid, partial melting with a non-viscous liquid, chemical reaction sintering and solid state sintering. The work has aimed at improving the understanding of ash sintering mechanisms and quantifying their role in combustion and gasification. The work has been oriented in particular on the understanding of biomass ash behavior. The work has not directly focused on any specific technical application. However, results can also be applied on other fuels such as brown coal, petroleum coke, black liquor and different types of wastes (PDF, RDF, MSW). In one part of study the melting behavior was calculated for ten biomass ashes and compared with lab measurements of sintering tendencies. The comparison showed that the T{sub 15} temperatures, i.e. those temperatures at which the ashes contained 15 % molten phase, correlated fairly well with the temperature at which the sintering measurements detected sintering. This suggests that partial melting can be predicted fairly accurate for some ashes already with the today existing thermodynamic calculation routines. In some cases, however the melting calculations did not correlate with the detected sintering temperatures. In a second part detailed measurements on ash behavior was conducted both in a semi full scale CFB and a lab scale FBC. Ashes and deposits were collected and analyzed in several different ways. These analyses show that the ash chemistry shifts radically when the fuel is shifted. Fuels with silicate based ashes behaved totally different than those with an oxide or salt based ash. The chemistry was also affected by fuel blending. The ultimate goal has been to be able to predict the ash thermal behavior during biomass thermal conversion, using the fuel and ash elemental analyses and a few operational key parameters as the only input data. This goal has not yet today been achieved. (author)

  1. Chemical composition and properties of spray-dried sugar beet concentrate obtained after ultrafiltration of diffusion juice

    Directory of Open Access Journals (Sweden)

    Regiec Piotr

    2015-03-01

    Full Text Available Ultrafiltration of diffusion juice is a method that can reduce environmental pollution during the production of sugar. A by-product (concentrate of ultrafiltration contains a large amount of sucrose, but due to its properties, it is difficult to manage. The aim of this study was to determine the effects of the temperature used during drying of diffusion juice concentrates on the content of certain components and characteristics of resultant preparations. Diffusion juice obtained from one of the Polish sugar plants was subjected to ultrafiltration and the obtained concentrates were dried in a spray dryer. In the dried samples, the following parameters were analyzed: dry mass, sucrose, total ash, protein, crude fiber and color. It has been declared that the degree of concentration and drying temperature influenced the chemical composition and the properties of the dehydrated diffusion juice concentrates. An increase in drying temperature was accompanied by the increased content of dry mass, protein, ash and fiber content in the preparations. The greater the degree of juice concentration, the greater was the content of dry mass, ash, and fiber. Inversely, the greater the degree of juice concentration, the lower the content of sucrose. The brightest color of the dehydrated product was observed at the drying temperature of 200°C. Spray-drying may be used for waste management after the diffusion juice membrane filtration, and the resultant preparations might be used in the production of feedstuff or food industry in general e.g. as sucrose source, in fermentation processes or in microorganisms propagation.

  2. Geotechnical properties of ash deposits near Hilo, Hawaii

    Science.gov (United States)

    Wieczorek, G.F.; Jibson, R.W.; Wilson, R.C.; Buchanan-Banks, J. M.

    1982-01-01

    Two holes were hand augered and sampled in ash deposits near Hilo, Hawaii. Color, water content and sensitivity of the ash were measured in the field. The ash alternated between reddish brown and dark reddish brown in color and had water contents as high as 392%. A downhole vane shear device measured sensitivities as high as 6.9. A series of laboratory tests including grain size distribution, Atterberg limits, X-ray diffraction analysis, total carbon determination, vane shear, direct shear and triaxial tests were performed to determine the composition and geotechnical properties of the ash. The ash is very fine grained, highly plastic and composed mostly of gibbsite and amorphous material presumably allophane. The ash has a high angle of internal friction ranging from 40-43? and is classified as medium to very sensitive. A series of different ash layers was distinguished on the basis of plasticity and other geotechnical properties. Sensitivity may be due to a metastable fabric, cementation, leaching, high organic content, and thixotropy. The sensitivity of the volcanic ash deposits near Hilo is consistent with documented slope instability during earthquakes in Hawaii. The high angles of internal friction and cementation permit very steep slopes under static conditions. However, because of high sensitivity of the ash, these slopes are particularly susceptible to seismically-induced landsliding.

  3. Assessing fly ash treatment: remediation and stabilization of heavy metals.

    Science.gov (United States)

    Lima, A T; Ottosen, Lisbeth M; Ribeiro, Alexandra B

    2012-03-01

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Strength Characteristics of Fiber Reinforced Quarry Dust Stabilized Fly Ash

    OpenAIRE

    Akshaya Kumar Sabat; Bidula Bose

    2015-01-01

    Effects of quarry dust and polypropylene fiber on compaction properties, shear strength parameters, and California bearing ratio (CBR) of a fly ash have been discussed in this paper. Quarry dust was added to a fly ash from 0 to 60% at an increment of 10%, compaction and soaked CBR tests were conducted on fly ash-quarry dust mixes and the optimum percentage of quarry dust was found out to be 40%. Polypropylene fiber was added to fly ash stabilized with optimum percentage of quarry dust, from 0...

  5. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    KAUST Repository

    Lima, A.T.

    2010-12-17

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

  6. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    KAUST Repository

    Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2010-01-01

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

  7. Characterization of North American lignite fly ashes. II. XRD Mineralogy

    International Nuclear Information System (INIS)

    McCarthy, G.J.; Johansen, D.M.; Thedchanamoorthy, A.; Steinwand, S.J.; Swanson, K.D.

    1988-01-01

    X-ray powder diffraction has been used to determine the crystalline phase mineralogy in samples of fly ash from each of the lignite mining areas of North America. The characteristic phases of North Dakota lignite fly ashes were periclase, lime, merwinite and the sulfate phases anhydrite, thenardite and a sodalite-structure phase. Mullite was absent in these low-Al/sub 2/O/sub 3/ ashes. Montana lignite ash mineralogy had characteristics of ND lignite and MT subbituminous coal fly ashes; mullite and C/sub 3/A were present and the alkali sulfates were absent. Texas and Louisiana lignite fly ashes had the characteristic mineralogy of bituminous coal fly ash: quartz, mullite, ferrite-spinel (magnetite) and minor hematite. Even though their analytical CaO contents were 7-14%, all but one lacked crystalline CaO-containing phases. Lignite fly ashes from Saskatchewan were generally the least crystalline of those studied and had a mineralogy consisting of quartz, mullite, ferrite spinel and periclase. Quantitative XRD data were obtained. The position of the diffuse scattering maximum in the x-ray diffractograms was indicative of the glass composition of the lignite fly ash

  8. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    DEFF Research Database (Denmark)

    Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2012-01-01

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialy......Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through...

  9. Chemical forms of the fluorine and carbon in fly ashes recovered from electrostatic precipitators of pulverized coal-fired plants

    Energy Technology Data Exchange (ETDEWEB)

    Naoto Tsubouchi; Hidekazu Hayashi; Akiyuki Kawashima; Masahide Sato; Noboru Suzuki; Yasuo Ohtsuka [Tohoku University, Sendai (Japan). Institute of Multidisciplinary Research for Advanced Materials

    2011-01-15

    The functionalities of the fluorine and carbon present in fly ashes formed in pulverized coal combustion have been studied with X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD) techniques. The ash samples include 20-130 {mu}g/g-dry and 0.4-4.1 mass%-dry of fluorine and carbon elements, respectively, and these components are enriched at the outermost layer of the ash surface. The F consists of both inorganic and organic functionalities, and the proportion of the latter is as high as 84-98 mol%. The C has different types of surface oxygen species, such as carboxyl, lactone/acid anhydride and phenolic groups, and most of these groups decompose to CO{sub 2} or CO up to 700{sup o}C to yield carbon active sites. When the amount of the O-functional forms increases, the content of organic C-F forms tends to increase almost linearly. On the basis of the above results, it may be speculated as one possibility that the formation of covalent C-F bonds takes place mainly through secondary reactions between gaseous F-containing compounds (HF and/or F{sub 2}) in flue gas and carbon active sites produced below 700{sup o}C downstream of coal-fired boilers. 30 refs., 8 figs., 4 tabs.

  10. Natural rain - induced element leaching from coal ASH; La pluie naturelle - lixiviation d'element de la cendre de charbon

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, A.; Djordjevic, D.; Polic, P. [Belgrade Univ., Dept. of Chemistry, IChTM, Chemistry Center, Belgrade (Yugoslavia)

    2000-07-01

    Six composite samples of coal ash from power plants 'Nikola Tesla' A and B, located in the vicinity of Obrenovac, near Belgrade (Yugoslavia), were subjected to extraction with 1 M acetate solution, pH 5.5, in order to imitate possible leaching of the ash by natural acidic rain. Seven trace and five major elements have been examined, and the obtained amounts were in the range from 0.003 {+-} 0.001 ppm (Cd), to 117 {+-} 27 ppm (Ca), dry ash basis. Though some of the concentrations were higher than allowed by domestic and international regulations it can be concluded that neither of the examined elements represents a serious threat for the environment (at least for the conditions applied in this experiment). Also, both magnesium and iron are carriers of copper, chromium and arsenic, while cadmium is associated with magnesium and manganese. Calcium and manganese are beside magnesium and iron, scavengers of arsenic. (authors)

  11. Briquettes of rice husk, polyethylene terephthalate (PET), and dried leaves as implementation of wastes recycling

    Science.gov (United States)

    Hariyanto, Sucipto; Usman, Mohammad Nurdianfajar; Citrasari, Nita

    2017-06-01

    This research aim is to determine the best briquettes as implementation of wastes recycle based on scoring method, main component composition, compressive strength, caloric value, water content, vollatile content, and ash content, also the suitability with SNI 01-6235-2000. Main component that used are rice husk, 2mm and 6 mm PET, and dried leaves. Composition variation in this research are marked as K1, K2, K3, K4, and K5 with 2 mm PET plastic and K1, K2, K3, K4, and K5 with 6 mm PET plastic. The total weight of the briquettes is 100 g and divided into 90% main components and 10% tapioca as binder. The compressive strength, caloric value, water content, vollatile content, and ash content were tested according to ASTM D 5865-04, ASTM D 3173-03, ASTM D 3175-02, ASTM D 3174-02. The tested results were used to determine the best briquette by scoring method, and the chosen briquettes is K2 with 6 mm PET plastic. The composition is 70% rice husk, 20% 6 mm PET plastic, and 10% dried leaves with the compressive strength, caloric value, water content, vollatile content, and ash content value is 51,55 kg/cm2; 5123 kal/g; 3,049%; 31,823%, dan 12,869%. The suitable value that meet the criteria according to SNI 01-6235-2000 is compressive strength, caloric value, water content, and ash content.

  12. Coal preparation and coal cleaning in the dry process; Kanshiki sentaku to coal cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Z; Morikawa, M; Fujii, Y [Okayama University, Okayama (Japan). Faculty of Engineering

    1996-09-01

    Because the wet process has a problem such as waste water treatment, coal cleaning in the dry process was discussed. When a fluidized bed (using glass beads and calcium carbonate) is utilized instead of the heavy liquid, the fluidized bed will have apparent density as the liquid does, whereas the relative relationship therewith determines whether a substance having been put into the fluidized bed will float or sink. This is utilized for coals. In addition, two powder constituents of A and B may be wanted to be separated using the fluidized extraction process (similar to the liquid-liquid extraction process). In such a case, a fluidized bed in which both constituents are mixed is added with a third constituent C (which will not mix with A, but mix well with B), where the constituents are separated into A and (B + C), and the (B + C) constituent is separated further by using a sieve. If coal has the coal content mixed with ash content and pulverized, it turns into particle groups which have distributions in grain size and density. Groups having higher density may contain more ash, and those having lower density less ash. In addition, the ash content depends also on the grain size. The ash content may be classified by using simultaneously wind classification (for density and grain size) and a sieve (for grain size). This inference may be expanded to consideration of constructing a multi-stage fluidized bed classification tower. 12 figs., 5 tabs.

  13. The influence of using volcanic ash and lime ash as filler on compressive strength in self compacting concrete

    Science.gov (United States)

    Karolina, Rahmi; Panatap Simanjuntak, Murydrischy

    2018-03-01

    Self Compacting Concrete (SCC) is a technology which is developing today in which concrete solidifies by itself without using vibrator. Casting conventional concrete which has a lot of reinforcement bars sometimes finds difficulty in achieving optimal solidity. The method used to solve this problem is by using SCC technology. SCC was made by using filler, volcanic ash, and lime ash as the filling materials so that the concrete became more solid and hollow space could be filled up. The variation of using these two materials was 10%, 15%, 20%, and 25% of the cementitious mass and using 1% of superplasticizer from cementitious material. The supporting testing was done by using the test when the concrete was still fluid and when it was solid. Malleable concrete was tested by using EFNARC 2002 standard in slump flow test, v-funnel test, l-shaped box test, and j-ring test to obtain filling ability and passing ability. In this malleable lime concrete test, there was the decrease, compared with normal SCC concrete without adding volcanic ash and lime ash. Testing was also done in solid concrete in compressive strength, tensile strength, and concrete absorption. The result of the testing showed that the optimum tensile strength in Variation 1, without volcanic ash and lime ash – with 1% of superplasticizer was 39.556 MPa, the optimum tensile strength in Variation 1, without volcanic ash and lime ash- with 1% of super-plasticizer was 3.563 MPa, while the value of optimum absorption which occurred in Variation 5 (25% of volcanic ash + 25% of lime ash + 50% of cement + 1% of superplasticizer) was 1.313%. This was caused by the addition of volcanic ash and lime ash which had high water absorption.

  14. Differential growth and yield by canola (Brassica napus L.) and wheat (Triticum aestivum L.) arising from alterations in chemical properties of sandy soils due to additions of fly ash.

    Science.gov (United States)

    Yunusa, Isa A M; Manoharan, Veeragathipillai; Harris, Rob; Lawrie, Roy; Pal, Yash; Quiton, Jonathan T; Bell, Richard; Eamus, Derek

    2013-03-30

    There is a need for field trials on testing agronomic potential of coal fly ash to engender routine use of this technology. Two field trials were undertaken with alkaline and acidic fly ashes supplied at between 3 and 6 Mg ha⁻¹ to acidic soils and sown to wheat and canola at Richmond (Eastern Australia) and to wheat only at Merredin (Western Australia). Ash addition marginally (PAPSIM at Richmond over a 100-year period (1909-2008) predicted yield increases in 52% of years with addition of ash at 3.0 Mg ha⁻¹ compared with 24% of years with addition of ash at 6.0 Mg ha⁻¹. The simulated yield increases did not exceed 40% over the control with addition of 6 Mg ha⁻¹ ash, but was between 40% and 50% with an addition rate of 3 Mg ha⁻¹. We found no evidence of phytotoxicity in either crop in this unusually dry year and there is still a need for further field assessment in years with favourable rainfall to enable development of clear recommendations on fly ash rates for optimum yield benefits. © 2012 Society of Chemical Industry.

  15. The relationship between the emerald ash borer (Agrilus planipennis) and ash (Fraxinus spp.) tree decline: Using visual canopy condition assessments and leaf isotope measurements to assess pest damage

    Science.gov (United States)

    Charles E. Flower; Kathleen S. Knight; Joanne Rebbeck; Miquel A. Gonzalez-Meler

    2013-01-01

    Ash trees (Fraxinus spp.) in North America are being severely impacted by the invasive emerald ash borer (Agrilus planipennis Fairmaire) which was inadvertently introduced to the US in the 1990s from Asia. The emerald ash borer (EAB) is a phloem boring beetle which relies exclusively on ash trees to complete its life cycle. Larvae...

  16. Gas generation in incinerator ash; Gasbildning i aska

    Energy Technology Data Exchange (ETDEWEB)

    Arm, Maria; Lindeberg, Johanna; Rodin, Aasa; Oehrstroem, Anna; Backman, Rainer; Oehman, Marcus; Bostroem, Dan

    2006-02-15

    In recent years, explosions have occurred in certain phases of ash handling in Sweden. Investigations have revealed that hydrogen may have been present in all cases. The hydrogen is believed to be generated by chemical reactions of aluminium and other metals within the ash in the presence of water. The purpose with this study is to increase the knowledge of gas generation of incinerator ash. Thereby, guides for appropriate ash management can be introduced and the risk for further explosions prevented. The study has comprised analyses of the ash properties, such as chemical and physical composition and the pH, of ash from 14 incineration plants (mostly waste incineration plants). Different fractions of ash materials representing different parts of the process in each plant have been analysed. Furthermore, the fuel and the technical differences between the plants have been analysed. A tool for measuring the gas generation in the laboratory has been developed and the gas generation of the different ash materials at natural and increased pH was measured. Gas analyses and thermodynamic calculations have also been performed. The results showed that: bottom ash from fluidised bed boilers generated small amounts of gas at increased pH, much smaller amounts than the idle pass, cyclone and filter ash did, bottom ash from grate fired boilers generated more gas at increased pH than their cyclone ash and filter ash, with exception of the Linkoeping plant, all bio waste incineration plants generated ash with low gas generation potential, all fly ash materials with a gas generation potential of more than 10 l/kg originated from municipal waste incineration plants, filter ash that had been stored in oxygen rich environment generated significant less gas than fresh filter ash of the same origin, hardly any other gases were generated apart from hydrogen (very small amounts of acetone, furane, benzene and most likely methane were detected in some of the ash materials), there were no

  17. Effects of fly ash fineness on the mechanical properties of concrete

    Indian Academy of Sciences (India)

    ash to have positive impact on mechanical properties of concrete. ... coarse ashes and their physical–chemical properties were evaluated. ... important factor affecting index of puzzolanic activity was fineness of the fly ash, not its chemical.

  18. Alkali content of fly ash : measuring and testing strategies for compliance.

    Science.gov (United States)

    2015-04-01

    Sodium and potassium are the common alkalis present in fly ash. Excessive amounts of fly ash alkalis can cause efflorescence : problems in concrete products and raise concern about the effectiveness of the fly ash to mitigate alkali-silica reaction (...

  19. Effects of water availability on emerald ash borer larval performance and phloem phenolics of Manchurian and black ash.

    Science.gov (United States)

    Chakraborty, Sourav; Whitehill, Justin G A; Hill, Amy L; Opiyo, Stephen O; Cipollini, Don; Herms, Daniel A; Bonello, Pierluigi

    2014-04-01

    The invasive emerald ash borer (EAB) beetle is a significant threat to the survival of North American ash. In previous work, we identified putative biochemical and molecular markers of constitutive EAB resistance in Manchurian ash, an Asian species co-evolved with EAB. Here, we employed high-throughput high-performance liquid chromatography with photodiode array detection and mass spectrometry (HPLC-PDA-MS) to characterize the induced response of soluble phloem phenolics to EAB attack in resistant Manchurian and susceptible black ash under conditions of either normal or low water availability, and the effects of water availability on larval performance. Total larval mass per tree was lower in Manchurian than in black ash. Low water increased larval numbers and mean larval mass overall, but more so in Manchurian ash. Low water did not affect levels of phenolics in either host species, but six phenolics decreased in response to EAB. In both ashes, pinoresinol A was induced by EAB, especially in Manchurian ash. Pinoresinol A and pinoresinol B were negatively correlated with each other in both species. The higher accumulation of pinoresinol A in Manchurian ash after attack may help explain the resistance of this species to EAB, but none of the responses measured here could explain increased larval performance in trees subjected to low water availability. © 2013 John Wiley & Sons Ltd.

  20. Drying of Concrete

    DEFF Research Database (Denmark)

    Hansen, Kurt Kielsgaard; Geiker, Mette Rica; Nygaard, Peter Vagn

    2002-01-01

    Estimated and measured relative humidity (RH) change during drying are compared for two concretes, 1: w/c=0.46 and 2: w/(c+0.5fa+2sf)=0.50. The estimations were undertaken by means of the Swedish program TorkaS 1.0. Measurements were performed by RH-sensors type Humi-Guard. Drying of 150 mm thick...... samples from sides at 60% RH and 22 °C took place from 4 to 56 days after casting. At the end of the drying period the measured RH was about 4% lower than the estimated RH at 1/5th depth from the exposed surface for both concretes. In the middle of the samples, the measured RH of concretes 1 and 2 were 2...

  1. Application of Coal Ash to Postmine Land for Prevention of Soil Erosion in Coal Mine in Indonesia: Utilization of Fly Ash and Bottom Ash

    Directory of Open Access Journals (Sweden)

    Shinji Matsumoto

    2016-01-01

    Full Text Available The increase in the number of coal-fired power plants with the increase in coal production and its consumption has caused the problem of the treatment of a large amount of coal ash in Indonesia. In the past studies, coal ash was applied to postmine land with the aim of improving soil conditions for plant growth; however, heavy rain in the tropical climate may cause soil erosion with the change in soil conditions. This study presents the effects of application of coal ash to postmine land on soil erosion by performing the artificial rainfall test as well as physical testing. The results indicate that the risk of soil erosion can be reduced significantly by applying the coal ash which consists of more than 85% of sand to topsoil in the postmine land at the mixing ratio of over 30%. Additionally, they reveal that not only fine fractions but also microporous structures in coal ash enhance water retention capacity by retaining water in the structure, leading to the prevention of soil erosion. Thus, the risk of soil erosion can be reduced by applying coal ash to topsoil in consideration of soil composition and microporous structure of coal ash.

  2. Patterns among the ashes: Exploring the relationship between landscape pattern and the emerald ash borer

    Science.gov (United States)

    Susan J. Crocker; Dacia M. Meneguzzo; Greg C. Liknes

    2010-01-01

    Landscape metrics, including host abundance and population density, were calculated using forest inventory and land cover data to assess the relationship between landscape pattern and the presence or absence of the emerald ash borer (EAB) (Agrilus planipennis Fairmaire). The Random Forests classification algorithm in the R statistical environment was...

  3. Tensile Adhesion Strength of Biomass Ash Deposits: Effect of the Temperature Gradient and Ash Chemistry

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Nair, Akhilesh Balachandran; Jensen, Peter Arendt

    2018-01-01

    Replacing coal with biomass in power plants is a viable option for reducing net CO2 emissions and combating climate change. However, biomass combustion in boilers may exacerbate problems related to ash deposition and corrosion, demanding effective deposit removal. The tensile adhesion strength...

  4. Spectral analysis of white ash response to emerald ash borer infestations

    Science.gov (United States)

    Calandra, Laura

    The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) is an invasive insect that has killed over 50 million ash trees in the US. The goal of this research was to establish a method to identify ash trees infested with EAB using remote sensing techniques at the leaf-level and tree crown level. First, a field-based study at the leaf-level used the range of spectral bands from the WorldView-2 sensor to determine if there was a significant difference between EAB-infested white ash (Fraxinus americana) and healthy leaves. Binary logistic regression models were developed using individual and combinations of wavelengths; the most successful model included 545 and 950 nm bands. The second half of this research employed imagery to identify healthy and EAB-infested trees, comparing pixel- and object-based methods by applying an unsupervised classification approach and a tree crown delineation algorithm, respectively. The pixel-based models attained the highest overall accuracies.

  5. The effect of nano-silica fertilizer concentration and rice hull ash doses on soybean (Glycine max (L.) Merrill) growth and yield

    Science.gov (United States)

    Suciaty, T.; Purnomo, D.; Sakya, A. T.; Supriyadi

    2018-03-01

    Agriculture is facing a number of challenges included limited water supply, low nutrient use efficiency, etc affected by climate change. Nano-silica is a product of nanotechnology, the frontier technologies to enhance crop productivity under climate change threats. The purpose of the research was to investigate the effects of nano silica concentration and rice hull ash on growth and yield of soybean. The experiment was conducted at Gagasari village, Cirebon, West Java from March until June 2017. The treatments were arranged by using factorial completely randomized block design with two factors. The first factor was a concentration of nano silica fertilizer consisted of four levels i.e., 0, 1.75, 2.5, and 3.75 ml.l‑1. The second factor was doses of rice hull ash consisted of four levels i.e., 0, 1, 2, and 3 ton.ha‑1. Each treatment combinations was repeated three times. The result showed that concentration of nano silica individually affected the number of leaves and number of branches, NAR and RGR, productive branches at 21, 30-45, and 35 daps, respectively. It also affected the seed dry weight plant‑1 and plot‑1. Meanwhile, doses of rice hull ash affected LAI, NAR, and RGR, 15-30, and 30-45 dap, respectively. Dry seed weight plot‑1 was also affected by doses of rice hull ash. There was an interaction effect between nano-silica concentration and doses of rice hull ash on number pods.plant‑1. Combinations of 2.5 ml.l‑1 nano-silica and 3 ton.ha‑1 of rice hull ash gave the highest number pods.plant‑1.

  6. Radioactivity of coals and fly ashes

    International Nuclear Information System (INIS)

    Papastefanou, C.

    2008-01-01

    The level and the behavior of the naturally occurring primordial radionuclides 238 U, 226 Ra, 210 Pb, 232 Th, 228 Ra and 40 K in coals and fly ashes are described. The activity concentrations of the examined coals and originated from coal mines in Greece ranged from 117 to 435 Bq x kg -1 for 238 U, from 44 to 255 Bq x kg -1 for 226 Ra, from 59 to 205 Bq x kg -1 for 210 Pb, from 9 to 41 Bq x kg -1 for 228 Ra and from 59 to 227 Bq x kg -1 for 40 K. These levels are comparable to those appeared in coals of different countries worldwide. The activity concentrations of the examined fly ashes and produced in coal-fired power plants in Greece ranged from 263 to 950 Bq x kg -1 for 238 U, from 142 to 605 Bq x kg -1 for 226 Ra, from 133 to 428 Bq x kg -1 for 210 Pb, from 27 to 68 Bq x kg -1 for 228 Ra and from 204 to 382 Bq x kg -1 for 40 K. The results showed that there is an enrichment of the radionuclides in fly ash relative to the input coal during the combustion process. The enrichment factors (EF) ranged from 0.60 to 0.76 for 238 U, from 0.69 to 1.07 for 226 Ra, from 0.57 to 0.75 for 210 Pb, from 0.86 to 1.11 for 228 Ra and from 0.95 to 1.10 for 40 K. (author)

  7. Radioactivity of Yatagan lignites and their ash

    International Nuclear Information System (INIS)

    Cicek, F.; Mustafaev, I.; Aliyev, C.

    2004-01-01

    Full text: One of harmful factor of Environmental impact of coal combustion is radiation pollution of Environment. The natural radioisotopes - uranium, thorium and potassium and products of their radioactive destruction contains of radionuclides. These radionuclides in composition of fly ash are thrown to atmosphere from coal combustion furnaces. The concentration of radioisotopes in composition of coals changes in the wide ranges: from 3 up to 520 Becquerel per kilogram (Bq/kg) for Uranium-238 and from 3 up to 320 Bq/kg for thorium-232. The radioactive pollution degree of environment depends on radioisotopes content of initial fuels. In this connection at the estimation of outlook and exploitation of coal mines it is necessary to determine of radioisotopes concentration in coals. That is why investigation of radioisotopes concentration of Turkish lignites has great importance. In this work the radionuclide content of Yatagan lignites and their ash, taken from Gekova thermal Electro station have been studied. The total radiation background generated by these samples was investigated by using of dosimeters 8P-5, CRP-88H, PYB-OIP. Radionuclides content of samples was determined in the Institute of Geology Azerbaijan national Academy of Sciences by using of highly sensitivity gamma-spectrometer CAPU-2, designed by Special Constructor Buro G eophysika . The plant allows to determine the radioisotopes content of solid and liquid samples with highly reliability. It has been established that in sample of lignite uranium content (on the radium equivalent) is 68 Bq/kg, potassium-149 Bq/kg and thorium is absent. The total radioactivity of lignite sample is 79,7 Bq/kg. In the ash sample uranium content is 266 Bq/kg, potassium-188 Bq/kg, and total activity reach to 300 Bq/kg. The possibility of application of purification erection for radionuclides from smoke gases of coal combustion is discussed

  8. Detecting Volcanic Ash Plumes with GNSS Signals

    Science.gov (United States)

    Rainville, N.; Larson, K. M.; Palo, S. E.; Mattia, M.; Rossi, M.; Coltelli, M.; Roesler, C.; Fee, D.

    2016-12-01

    Global Navigation Satellite Systems (GNSS) receivers are commonly placed near volcanic sites to measure ground deformation. In addition to the carrier phase data used to measure ground position, these receivers also record Signal to Noise ratio (SNR) data. Larson (2013) showed that attenuations in SNR data strongly correlate with ash emissions at a series of eruptions of Redoubt Volcano. This finding has been confirmed at eruptions for Tongariro, Mt Etna, Mt Shindake, and Sakurajima. In each of these detections, very expensive geodetic quality GNSS receivers were used. If low-cost GNSS instruments could be used instead, a networked array could be deployed and optimized for plume detection and tomography. The outputs of this sensor array could then be used by both local volcanic observatories and Volcano Ash Advisory Centers. Here we will describe progress in developing such an array. The sensors we are working with are intended for navigation use, and thus lack the supporting power and communications equipment necessary for a networked system. Reliably providing those features is major challenge for the overall sensor design. We have built prototypes of our Volcano Ash Plume Receiver (VAPR), with solar panels, lithium-ion batteries and onboard data storage for preliminary testing. We will present results of our field tests of both receivers and antennas. A second critical need for our array is a reliable detection algorithm. We have tested our algorithm on data from recent eruptions and have incorporated the noise characteristics of the low-cost GNSS receiver. We have also developed a simulation capability so that the receivers can be deployed to optimize vent crossing GNSS signals.

  9. Synthesis of geopolymer from biomass-coal ash blends

    Science.gov (United States)

    Samadhi, Tjokorde Walmiki; Wulandari, Winny; Prasetyo, Muhammad Iqbal; Fernando, Muhammad Rizki; Purbasari, Aprilina

    2017-09-01

    Geopolymer is an environmentally attractive Portland cement substitute, owing to its lower carbon footprint and its ability to consume various aluminosilicate waste materials as its precursors. This work describes the development of geopolymer formulation based on biomass-coal ash blends, which is predicted to be the prevalent type of waste when biomass-based thermal energy production becomes mainstream in Indonesia. The ash blends contain an ASTM Class F coal fly ash (FA), rice husk ash (RHA), and coconut shell ash (CSA). A mixture of Na2SiO3 and concentrated KOH is used as the activator solution. A preliminary experiment identified the appropriate activator/ash mass ratio to be 2.0, while the activator Na2SiO3/KOH ratio varies from 0.8 to 2.0 with increasing ash blend Si/Al ratio. Both non-blended FA and CSA are able to produce geopolymer mortars with 7-day compressive strength exceeding the Indonesian national SNI 15-2049-2004 standard minimum value of 2.0 MPa stipulated for Portland cement mortars. Ash blends have to be formulated with a maximum RHA content of approximately 50 %-mass to yield satisfactory 7-day strength. No optimum ash blend composition is identified within the simplex ternary ash blend compositional region. The strength decreases with Si/Al ratio of the ash blends due to increasing amount of unreacted silicate raw materials at the end of the geopolymer hardening period. Overall, it is confirmed that CSA and blended RHA are feasible raw materials for geopolymer production..

  10. A robust method to forecast volcanic ash clouds

    Science.gov (United States)

    Denlinger, Roger P.; Pavolonis, Mike; Sieglaff, Justin

    2012-01-01

    Ash clouds emanating from volcanic eruption columns often form trails of ash extending thousands of kilometers through the Earth's atmosphere, disrupting air traffic and posing a significant hazard to air travel. To mitigate such hazards, the community charged with reducing flight risk must accurately assess risk of ash ingestion for any flight path and provide robust forecasts of volcanic ash dispersal. In response to this need, a number of different transport models have been developed for this purpose and applied to recent eruptions, providing a means to assess uncertainty in forecasts. Here we provide a framework for optimal forecasts and their uncertainties given any model and any observational data. This involves random sampling of the probability distributions of input (source) parameters to a transport model and iteratively running the model with different inputs, each time assessing the predictions that the model makes about ash dispersal by direct comparison with satellite data. The results of these comparisons are embodied in a likelihood function whose maximum corresponds to the minimum misfit between model output and observations. Bayes theorem is then used to determine a normalized posterior probability distribution and from that a forecast of future uncertainty in ash dispersal. The nature of ash clouds in heterogeneous wind fields creates a strong maximum likelihood estimate in which most of the probability is localized to narrow ranges of model source parameters. This property is used here to accelerate probability assessment, producing a method to rapidly generate a prediction of future ash concentrations and their distribution based upon assimilation of satellite data as well as model and data uncertainties. Applying this method to the recent eruption of Eyjafjallajökull in Iceland, we show that the 3 and 6 h forecasts of ash cloud location probability encompassed the location of observed satellite-determined ash cloud loads, providing an

  11. Mixing process influence on thermal and rheological properties of NBR/SiO2 from rice husk ash

    Directory of Open Access Journals (Sweden)

    Ana Maria Furtado de Sousa

    Full Text Available Abstract Silica was extracted from rice husk ash (RHA by a sequence of reactions to produce nanosilica. Two laboratory routes, co-coagulation and spray drying, were used to incorporate the nanosilica into the rubber matrix. Samples were characterized regarding filler incorporation efficiency, thermal stability, rheological behavior and morphology. Thermogravimetric analysis showed that spray-drying was the most efficient filler incorporation process and also the presence of silica increased the thermal resistance of the rubber compound when compared to the unfilled rubber. The rheological behavior showed that NBR filled with silica presented higher elastic torque (S’, storage modulus (G’ and complex viscosity (η* than unfilled rubber. The Payne effect was also observed for the composites produced by spray-drying. In addition, the thermal behavior and Payne effect results were supported by the comparison of morphology observed by FEG-SEM analysis.

  12. Sintering of a class F fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Joseph J. Biernacki; Anil K. Vazrala; H. Wayne Leimer [Tennessee Technological University, Cookeville, TN (United States). Department of Chemical Engineering

    2008-05-15

    The sinterability of a class F fly ash was investigated as a function of processing conditions including sintering temperature (1050-1200{sup o}C) and sintering time (0-90 min). Density, shrinkage, splitting tensile strength, water absorption and residual loss on ignition (RLOI) were evaluated as measures of sintering efficiency. Scanning electron microscopy (SEM), X-ray microanalysis and X-ray diffraction was used to examine microstructure and phase development due to processing. The results show that premature densification can inhibit complete carbon removal and that carbon combustion is influenced by both internal and external mass transfer conditions. 18 refs., 10 figs., 1 tab.

  13. Pemanfaatan Bottom Ash Sebagai Agregat Buatan

    OpenAIRE

    Nuciferani, Felicia Tria; Antoni, Antoni; Hardjito, Djwantoro

    2014-01-01

    The aim of this study is to explore the possible use of bottom ash as artificial aggregates. It is found that the pelletizer method by using mixer without blade is one possibility to manufacture artificial aggregates. The optimum mixture composition of artificial aggregate is found to be 3 BA : 1FA : 0,5 C , by weight, and immersed once in cement slurry. The water content in ssd condition is 27% with the compressive strength of the aggregate 2.4 MPa on the seventh day. Concrete produced with ...

  14. Pecan drying with silica gel

    Energy Technology Data Exchange (ETDEWEB)

    Ghate, S.R.; Chhinnan, M.S.

    1983-07-01

    High moisture in-shell pecans were dried by keeping them in direct and indirect contact with silica gel to investigate their drying characteristics. In-shell pecans were also dried with ambient air from a controlled environment chamber and with air dehumidified by silica gel. Direct contact and dehumidified air drying seemed feasible approaches.

  15. Comparative Study of the Use of Different Biomass Bottom Ash in the Manufacture of Ceramic Bricks

    OpenAIRE

    Eliche-Quesada, D; Felipe Sesé, Manuel Ángel (UNIR); Martínez-Martínez, S; Pérez-Villarejo, L

    2017-01-01

    The present study evaluates the suitability of several types of biomass bottom ashes [wood bottom ash (WBA), pine-olive pruning bottom ash (POPBA), olive stone bottom ash (OSBA), and olive pomace bottom ash (OPBA)] as an alternative source to replace ceramic raw material in the production of clay bricks. The clay and biomass bottom ash were characterized by means of X-ray diffraction (XRD) (crystallinity), X-ray fluorescence spectroscopy (XRF) (chemical composition), carbon, nitrogen, hydroge...

  16. Land application uses for dry FGD by-products

    Energy Technology Data Exchange (ETDEWEB)

    Bigham, J.; Dick, W.; Forster, L.; Hitzhusen, F.; McCoy, E.; Stehouwer, R.; Traina, S.; Wolfe, W. (Ohio State Univ., Columbus, OH (United States)); Haefner, R. (Geological Survey, Columbus, OH (United States). Water Resources Div.)

    1993-04-01

    The 1990 amendments to the Clean Air Act have spurred the development of flue gas desulfurization (FGD) processes, several of which produce a dry, solid by-product material consisting of excess sorbent, reaction products containing sulfates and sulfites, and coal fly ash. Presently FGD by-product materials are treated as solid wastes and must be landfilled. However, landfill sites are becoming more scarce and tipping fees are constantly increasing. It is, therefore, highly desirable to find beneficial reuses for these materials provided the environmental impacts are minimal and socially acceptable. Phase 1 results of a 4 and 1/2 year study to demonstrate large volume beneficial uses of FGD by-products are reported. The purpose of the Phase 1 portion of the project was to characterize the chemical, physical, mineralogical and engineering properties of the FGD by-product materials obtained from various FGD technologies being developed in the state of Ohio. Phase 1 also involved the collection of baseline economic data related to the beneficial reuse of these FGD materials. A total of 58 samples were collected and analyzed. In summary Phase 1 results revealed that FGD by-product materials are essentially coal fly ash materials diluted with unreacted sorbent and reaction products. High volume beneficial reuses will depend on the economics of their substituting for existing materials for various types of applications (e.g. as an agricultural liming material, soil borrow for highway embankment construction, and reclamation of active and abandoned surface coal mines). Environmental constraints to the beneficial reuse of dry FGD byproduct materials, based on laboratory and leachate studies, seem to be less than for coal fly ash.

  17. Utilisation of fly ash for the management of heavy metal containing primary chemical sludge generated in a leather manufacturing industry

    Energy Technology Data Exchange (ETDEWEB)

    Sekaran, G.; Rao, B.P.; Ghanamani, A.; Rajamani, S. [Central Leather Research Institute, Chennai (India). Dept. of Environmental Technology

    2003-07-01

    The present study aims at disposal of primary chemical sludge generated in the tanning industry by solidification and stabilization process using flyash generated from thermal power plant along with binders and also on evaluating the leachability of heavy metal from the solidified product. The primary chemical sludge containing heavy metals iron and chromium were obtained from a garment leather manufacturing company at Chennai in India. The sludge was dried in open environment and it was powdered to fine size in a grinder. Binding increases stabilization of heavy metal in calcined sludge with refractory binders such as clay, fly ash, lime and ordinary Portland cement. Fly ash can be considered as the additional binder for producing stronger bricks, with high metal fixation efficiency, and minimum rate of removal of heavy metal and minimum diffusion co-efficient. 15 refs., 5 figs., 5 tabs.

  18. Characteristics of Timbers Dried Using Kiln Drying and Radio Frequency-Vacuum Drying Systems

    Directory of Open Access Journals (Sweden)

    Rabidin Zairul Amin

    2017-01-01

    Full Text Available Heavy hardwoods are difficult-to-dry timbers as they are prone to checking and internal stresses when dried using a conventional kiln drying system. These timbers are usually dried naturally to reach 15% to 19% moisture content with an acceptable defects. Besides long drying time, timbers at these moisture contents are not suitable for indoor applications since they will further dry and causing, for example, jointing and lamination failures. Drying to a lower moisture content could only be achieved in artificial drying kilns such as conventional kiln, dehumidification kiln, solar kiln, radio frequency-vacuum, etc. The objective of this study was to evaluate the characteristics of 30 mm and 50 mm thick kekatong (Cynometra spp. timber dried using kiln drying (KD and radio frequency-vacuum drying (RFV system. The investigation involved drying time, moisture content (MC variations between and within boards, drying defects, shrinkage, and drying stress. Drying defects include checks (surface, end, and internal checks and warping (bowing, cuping, spring, and twisting. The results showed that RFV drying time was reduced to 50% compared to the KD. RFV dried boards demonstrated a more uniform MC between and within boards. Shrinkage in width and thickness, as well as tangential/radial and volumetric shrinkages were substantially less in RFV boards. The amount of cupping, bowing and spring were very low and negligible in all drying runs. There was no twisting observed in all drying methods. The number of stress-free RFV board was higher than KD. With proper procedure, the RFV technology could be used for drying heavy hardwoods which are difficult to dry in conventional kilns due to excessive drying times and degradation.

  19. The Effect of Operating Conditions on Drying Characteristics and Quality of Ginger (Zingiber Officinale Roscoe) Using Combination of Solar Energy-Molecular Sieve Drying System

    Science.gov (United States)

    Hasibuan, R.; Zamzami, M. A.

    2017-03-01

    , and the falling drying rate, while the constant drying rate is not visible. The result of ginger quality shows that there are no significant changes in the organoleptic analysis, the ash content is about 7.52-7.94% and the oil content is 0.79-0.83%.

  20. Volcanic ash modeling with the NMMB-MONARCH-ASH model: quantification of offline modeling errors

    Science.gov (United States)

    Marti, Alejandro; Folch, Arnau

    2018-03-01

    Volcanic ash modeling systems are used to simulate the atmospheric dispersion of volcanic ash and to generate forecasts that quantify the impacts from volcanic eruptions on infrastructures, air quality, aviation, and climate. The efficiency of response and mitigation actions is directly associated with the accuracy of the volcanic ash cloud detection and modeling systems. Operational forecasts build on offline coupled modeling systems in which meteorological variables are updated at the specified coupling intervals. Despite the concerns from other communities regarding the accuracy of this strategy, the quantification of the systematic errors and shortcomings associated with the offline modeling systems has received no attention. This paper employs the NMMB-MONARCH-ASH model to quantify these errors by employing different quantitative and categorical evaluation scores. The skills of the offline coupling strategy are compared against those from an online forecast considered to be the best estimate of the true outcome. Case studies are considered for a synthetic eruption with constant eruption source parameters and for two historical events, which suitably illustrate the severe aviation disruptive effects of European (2010 Eyjafjallajökull) and South American (2011 Cordón Caulle) volcanic eruptions. Evaluation scores indicate that systematic errors due to the offline modeling are of the same order of magnitude as those associated with the source term uncertainties. In particular, traditional offline forecasts employed in operational model setups can result in significant uncertainties, failing to reproduce, in the worst cases, up to 45-70 % of the ash cloud of an online forecast. These inconsistencies are anticipated to be even more relevant in scenarios in which the meteorological conditions change rapidly in time. The outcome of this paper encourages operational groups responsible for real-time advisories for aviation to consider employing computationally