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Sample records for bottom ash financial

  1. A method for treating bottom ash

    NARCIS (Netherlands)

    Rem, P.C.; Van Craaikamp, H.; Berkhout, S.P.M.; Sierhuis, W.; Van Kooy, L.A.

    2007-01-01

    A method for treating bottom ash from a waste incineration plant. The invention relates in particular to a method for treating bottom ash from a domestic waste incineration plant. In accordance with the invention bottom ash having a size ranging up to 2 mm is treated by removing a previously determi

  2. 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),

  3. 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),

  4. Toxicity of waste gasification bottom ash leachate.

    Science.gov (United States)

    Sivula, Leena; Oikari, Aimo; Rintala, Jukka

    2012-06-01

    Toxicity of waste gasification bottom ash leachate from landfill lysimeters (112 m(3)) was studied over three years. The leachate of grate incineration bottom ash from a parallel setup was used as reference material. Three aquatic organisms (bioluminescent bacteria, green algae and water flea) were used to study acute toxicity. In addition, an ethoxyresorufin-O-deethylase (EROD) assay was performed with mouse hepatoma cells to indicate the presence of organic contaminants. Concentrations of 14 elements and 15 PAH compounds were determined to characterise leachate. Gasification ash leachate had a high pH (9.2-12.4) and assays with and without pH adjustment to neutral were used. Gasification ash leachate was acutely toxic (EC(50) 0.09-62 vol-%) in all assays except in the algae assay with pH adjustment. The gasification ash toxicity lasted the entire study period and was at maximum after two years of disposal both in water flea (EC(50) 0.09 vol-%) and in algae assays (EC(50) 7.5 vol-%). The grate ash leachate showed decreasing toxicity during the first two years of disposal in water flea and algae assays, which then tapered off. Both in the grate ash and in the gasification ash leachates EROD-activity increased during the first two years of disposal and then tapered off, the highest inductions were observed with the gasification ash leachate. The higher toxicity of the gasification ash leachate was probably related to direct and indirect effects of high pH and to lower levels of TOC and DOC compared to the grate ash leachate. The grate ash leachate toxicity was similar to that previously reported in literature, therefore, confirming that used setup was both comparable and reliable. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Ash Management Review—Applications of Biomass Bottom Ash

    Directory of Open Access Journals (Sweden)

    Harpuneet S. Ghuman

    2012-10-01

    Full Text Available In industrialized countries, it is expected that the future generation of bioenergy will be from the direct combustion of residues and wastes obtained from biomass. Bioenergy production using woody biomass is a fast developing application since this fuel source is considered to be carbon neutral. The harnessing of bioenergy from these sources produces residue in the form of ash. As the demand for bioenergy production increases, ash and residue volumes will increase. Major challenges will arise relating to the efficient management of these byproducts. The primary concerns for ash are its storage, disposal, use and the presence of unburned carbon. The continual increase in ash volume will result in decreased ash storage facilities (in cases of limited room for landfill expansion, as well as increased handling, transporting and spreading costs. The utilization of ash has been the focus of many studies, hence this review investigates the likely environmental and technological challenges that increased ash generation may cause. The presence of alkali metals, alkaline earth metals, chlorine, sulphur and silicon influences the reactivity and leaching to the inorganic phases which may have significant impacts on soils and the recycling of soil nutrient. Discussed are some of the existing technologies for the processing of ash. Unburned carbon present in ash allows for the exploration of using ash as a fuel. The paper proposes sieve fractionation as a suitable method for the separation of unburnt carbon present in bottom ash obtained from a fixed-bed combustion system, followed by the application of the gasification technology to particle sizes of energy importance. It is hoped that this process will significantly reduce the volume of ash disposed at landfills.

  6. Biodegradable organic matter in municipal solid waste incineration bottom ash.

    Science.gov (United States)

    Zhang, Shuo; Herbell, Jan-Dirk; Gaye-Haake, Birgit

    2004-01-01

    For investigation of the behavior of municipal solid waste incineration bottom ash in landfill, we have analysed bottom ash samples taken after the quench tank as well as after five months of storage in the laboratory for elements and organic constituents. Water extractable organic carbon, particulate organic carbon, amino acids, hexosamines and carbohydrates considerably decreased during the five months of storage and their spectra revealed microbial reworking. This shows that the organic matter present in the bottom ash after incineration can provide a substrate for microbial activity. The resulting changes of the physico-chemical environment may effect the short-term behavior of the bottom ash in landfill. Copyright 2004 Elsevier Ltd.

  7. Use of Unprocessed Coal Bottom Ash as Partial Fine Aggregate ...

    African Journals Online (AJOL)

    2012r

    Bottom ash, the solid residue from electric power ... consumption and greenhouse gas emissions (GHG). In addition, it helps ... economic sense; they are often less costly than the materials they replace. (American Coal Ash ... and Kim and Lee (2011), observed a decrease in density due to the low specific gravity of the ash.

  8. 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.

  9. Pretreatment and utilization of waste incineration bottom ashes

    DEFF Research Database (Denmark)

    Astrup, Thomas

    2007-01-01

    Within recent years, researchers and authorities have had increasing focus on leaching properties from waste incineration bottom ashes. Researchers have investigated processes such as those related to carbonation, weathering, metal complexation, and leaching control. Most of these investigations...

  10. Effects of colemanite waste, coal bottom ash, and fly ash on the properties of cement

    Energy Technology Data Exchange (ETDEWEB)

    Kula, I.; Olgun, A.; Erdogan, Y.; Sevinc, V. [Celal Bayar University, Manisa (Turkey)

    2001-03-01

    The physical and chemical properties of colemanite ore waste from concentrator, coal bottom ash, fly ash, cement+ash mixtures, cement+colemanite ore waste, and their effects on the mechanical properties of concrete were investigated. These materials with different proportion were substituted with Portland cement. Physical properties such as setting time, volume expansion, and compressive strength were determined and compared to reference mixture and Turkish standards (TS). The results showed that cement replacement materials had clear effects on the mechanical properties. The use of fly ash and bottom ash even at the concentration of 25% showed either comparable or better result compared to reference mixture. Although replacement of Portland cement by 9 wt.% of colemanite ore waste causes reduction in the compressive strength, the values obtained are within the limit of TS. As a result, colemanite ore waste, fly ash, and bottom ash may be used as cementitious materials.

  11. Mswi bottom ash for upgrading of biogas and landfill gas.

    Science.gov (United States)

    Mostbauer, P; Lenz, S; Lechner, P

    2008-07-01

    A new upgrading process for biogas and landfill gas (LFG) has been designed recently by the authors' institute. The process uses the alkalinity of the fine fraction of bottom ash from municipal solid waste incineration (MSWI) for sorbing CO2 and H2S. Results from process development and optimisation are presented in this paper. It is expected that nearly pure CH4 can be produced for substitution of fossil fuels. Simultaneously, the leachability of MSWI bottom ash is clearly reduced.

  12. Formation of Humic Substances in Weathered MSWI Bottom Ash

    Directory of Open Access Journals (Sweden)

    Haixia Zhang

    2013-01-01

    Full Text Available The study aimed at evaluating the humic substances (HSs content from municipal solid waste incinerator (MSWI bottom ash and its variation with time and the effect of temperature on HSs formation. The process suggested by IHSS was applied to extract HSs from two different bottom ash samples, and the extracted efficiency with NaOH and Na4P2O7 was compared. MSWI bottom ash samples were incubated at 37∘C and 50∘C for 1 year. HSs and nonhumic substances were extracted from the bottom ash sample with different incubated period by 0.1 M NaOH/Na4P2O7. Results show that the rate of humic acid formation increased originally with incubation time, reached a maximum at 12th week under 37∘C and at 18th week under 50∘C, and then decreased with time. More humic acid in MSWI bottom ash was formed under 50∘C incubated condition compared with that incubated under 37∘C. Also, the elemental compositions of HSs extracted from bottom ash are reported.

  13. Behaviour of cement-treated MSWI bottom ash.

    Science.gov (United States)

    Pecqueur, G; Crignon, C; Quénée, B

    2001-01-01

    MSWI bottom ash is the residue of combustion. The use of bottom ash in road construction is wide spread. French legislation forbids the disposal of resuable waste in special landfill from 2002. Moreover, "arrêté du 9 mai 1994" provides environmental criteria (leaching threshold, etc.), and evaluates this material according to utilisation in road construction. In such application, bottom ash is often treated with binder to improve its mechanical features. Nevertheless, bottom ash is subject to chemical problems. These problems induce an expansion which brings about cracking and finally road destruction. Therefore, it is necessary to estimate the swelling potential of MSWI bottom ash prior utilisation. This is one of the aims of the European contract "Mashroad" (contract BRST CT97-5150). This study involved 4 years of work on cement-treated MSWI bottom ash. It examined different tests that show the importance of oxidation of aluminium in the swelling reaction and the efficiency of different treatments. Different binders were used in order to have different proportions of clinker. The kinetic aspects of aluminium-binder reaction were also studied. Finally, we present a special cell to measure the swelling pressure of these materials is presented.

  14. Removal of pollutants from wastewater by coal bottom ash.

    Science.gov (United States)

    Lin, Chiu-Yue; Yang, Dong-Hao

    2002-09-01

    Coal bottom ash produced from a thermal power plant was used in a batch experiment to investigate the adsorption characteristic of this bottom ash. The adsorbate solutions were synthetic wastewaters contained copper (Cu2+) or COD and a sanitary landfill leachate. The influences of various factors, such as contact time, pH, initial adsorbate concentration and temperature on the sorption have been studied. Experimental results show that coal bottom ash had a good adsorption capacity for copper and COD and could reduce the concentrations of various pollutants in the leachate. The adsorption capacities of each gram of coal bottom ash were 0.48 mg Cu (at pH 4 and temperature 25 degrees C) and 7.5 mg COD (at pH 5 and temperature 25 degrees C); their adsorption behaviors conformed to Freundlich's adsorption model. In treating leachate, the removal efficiencies of COD, NH3--N, total Kjeldah nitrogen, phosphorus, Fe3+, Mn2+ and Zn2+ were 47, 39.4, 31.1, 92.9, 96.5, 94.3 and 82.2%, respectively. Based on these results we can conclude that it is possible to use coal bottom ash for removing pollutants from wastewaters. The adsorption capacities of coal bottom ash for pollutants were also determined.

  15. 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.

  16. Glass phase in municipal and industrial waste incineration bottom ashes

    Science.gov (United States)

    Rafał Kowalski, Piotr; Michalik, Marek

    2015-04-01

    Waste incineration bottom ash is a material with rising significance in waste streams in numerous countries. Even if some part of them is now used as raw materials the great amount is still landfilled. High temperature of thermal processes (>1000°C) together with fast cooling results in high content of glass in bottom ash. Its chemical composition is influenced by various factors like composition of raw wastes and used incineration technique. Most of bottom ash grains are composed of glass with large amount of mineral phases and also metallic constituents embedded into it. Glass susceptibility for alteration processes together with the characteristics of glass-based grains can bring environmental risk in time of improper or long term storage on landfill site. In this study bottom ashes from thermal treatment of municipal and industrial (including hazardous and medical) wastes were studied to determine glass content, its chemical composition with emphasis on metal content (especially potentially hazardous) and its relations to metallic components of grains. Samples were collected from two thermal treatment plants in Poland. Qualitative and quantitative X-ray diffraction (XRD) analyses were used for determination of mineral composition of studied samples. Rietveld method and addition of internal standard for determination of amorphous phase content were used. Scanning electron microscopy fitted with energy dispersive spectrometry (SEM-EDS) were used for detailed analysis of glass and glass associated phases. Waste incineration bottom ash is a multi-components material rich in amorphous phase. It dominant part is represented by Si-rich glass. It is a main component of bottom ash grains but it contains minerals present in large quantities and also various forms of metallic elements. Glass within grains is often porous and cracked. In bottom ashes from thermal treatment of municipal wastes ~ 45-55 wt % of amorphous phase were present, mostly in form of glass with high

  17. Influence of Fly Ash, Bottom Ash, and Light Expanded Clay Aggregate on Concrete

    Directory of Open Access Journals (Sweden)

    S. Sivakumar

    2015-01-01

    Full Text Available Invention of new methods in strengthening concrete is under work for decades. Developing countries like India use the extensive reinforced construction works materials such as fly ash and bottom ash and other ingredients in RCC construction. In the construction industry, major attention has been devoted to the use of fly ash and bottom ash as cement and fine aggregate replacements. In addition, light expanded clay aggregate has been introduced instead of coarse aggregate to make concrete have light weight. This paper presents the results of a real-time work carried out to form light weight concrete made with fly ash, bottom ash, and light expanded clay aggregate as mineral admixtures. Experimental investigation on concrete mix M20 is done by replacement of cement with fly ash, fine aggregate with bottom ash, and coarse aggregate with light expanded clay aggregate at the rates of 5%, 10%, 15%, 20%, 25%, 30%, and 35% in each mix and their compressive strength and split tensile strength of concrete were discussed for 7, 28, and 56 days and flexural strength has been discussed for 7, 28, and 56 days depending on the optimum dosage of replacement in compressive strength and split tensile strength of concrete.

  18. Comparative study on the characteristics of fly ash and bottom ash geopolymers.

    Science.gov (United States)

    Chindaprasirt, Prinya; Jaturapitakkul, Chai; Chalee, Wichian; Rattanasak, Ubolluk

    2009-02-01

    This research was conducted to compare geopolymers made from fly ash and ground bottom ash. Sodium hydroxide (NaOH) and sodium silicate (Na(2)SiO(3)) solutions were used as activators. A mass ratio of 1.5 Na(2)SiO(3)/NaOH and three concentrations of NaOH (5, 10, and 15M) were used; the geopolymers were cured at 65 degrees C for 48 h. A Fourier transform infrared spectrometer (FT-IR), differential scanning calorimeter (DSC), and scanning electron microscope (SEM) were used on the geopolymer pastes. Geopolymer mortars were also prepared in order to investigate compressive strength. The results show that both fly ash and bottom ash can be utilized as source materials for the production of geopolymers. The properties of the geopolymers are dependent on source materials and the NaOH concentration. Fly ash is more reactive and produces a higher degree of geopolymerization in comparison with bottom ash. The moderate NaOH concentration of 10 M is found to be suitable and gives fly ash and bottom ash geopolymer mortars with compressive strengths of 35 and 18 MPa.

  19. Flowable Backfill Materials from Bottom Ash for Underground Pipeline

    Directory of Open Access Journals (Sweden)

    Kyung-Joong Lee

    2014-04-01

    Full Text Available The purpose of this study was to investigate the relationship between strength and strain in manufacturing controlled low strength materials to recycle incineration bottom ash. Laboratory tests for controlled low strength materials with bottom ash and recycled in-situ soil have been carried out. The optimum mixing ratios were 25%–45% of in-situ soil, 30% of bottom ash, 10%–20% of fly ash, 0%–3% of crumb rubber, 3% of cement, and 22% of water. Each mixture satisfied the standard specifications: a minimum 20 cm of flowability and 127 kPa of unconfined compressive strength. The average secant modulus (E50 was (0.07–0.08 qu. The ranges of the internal friction angle and cohesion for mixtures were 36.5°–46.6° and 49.1–180 kPa, respectively. The pH of all of the mixtures was over 12, which is strongly alkaline. Small-scale chamber tests for controlled low strength materials with bottom ash and recycled in-situ soil have been carried out. Vertical deflection of 0.88–2.41 mm and horizontal deflection of 0.83–3.72 mm were measured during backfilling. The vertical and horizontal deflections of controlled low strength materials were smaller than that of sand backfill.

  20. Precious Metals in Municipal Solid Waste Incineration Bottom Ash

    Energy Technology Data Exchange (ETDEWEB)

    Muchova, Lenka; Bakker, Erwin; Rem, Peter [Faculty of Civil Engineering and Geosciences, Materials and Environment, TU Delft (Netherlands)], E-mail: P.C.REM@TUDELFT.NL

    2009-04-15

    Municipal solid waste incineration (MSWI) bottom ash contains economically significant levels of silver and gold. Bottom ashes from incinerators at Amsterdam and Ludwigshafen were sampled, processed, and analyzed to determine the composition, size, and mass distribution of the precious metals. In order to establish accurate statistics of the gold particles, a sample of heavy non-ferrous metals produced from 15 tons of wet processed Amsterdam ash was analyzed by a new technology called magnetic density separation (MDS). Amsterdam's bottom ash contains approximately 10 ppm of silver and 0.4 ppm of gold, which was found in particulate form in all size fractions below 20 mm. The sample from Ludwigshafen was too small to give accurate values on the gold content, but the silver content was found to be identical to the value measured for the Amsterdam ash. Precious metal value in particles smaller than 2 mm seems to derive mainly from waste of electrical and electronic equipment (WEEE), whereas larger precious metal particles are from jewelry and constitute the major part of the economic value. Economical analysis shows that separation of precious metals from the ash may be viable with the presently high prices of non-ferrous metals. In order to recover the precious metals, bottom ash must first be classified into different size fractions. Then, the heavy non-ferrous (HNF) metals should be concentrated by physical separation (eddy current separation, density separation, etc.). Finally, MDS can separate gold from the other HNF metals (copper, zinc). Gold-enriched concentrates can be sold to the precious metal smelter and the copper-zinc fraction to a brass or copper smelter.

  1. The Effects of Bottom Ash from MSWI Used as Mineral Additions in Concrete

    Directory of Open Access Journals (Sweden)

    Che Amat Roshazita

    2017-01-01

    Full Text Available Municipal solid waste incinerators (MSWI produce by products which can be classified as bottom and fly ashes. The bottom ash accounts for 85–90 % of the solid product resulting from MSW combustion. The aimed of the present work is to study the effect of replacing partial of bottom ash were manufactured. Fresh and hardened properties of the concrete were compared in order to study the suitable cement-bottom ash replacement. Bottom ash was found to have some reactivity, but without greatly affecting the hydration process of OPC at 10 % replacement. However at more than 10 % replacement, the addition of bottom ash greatly affected strength.

  2. Workability and strength of lignite bottom ash geopolymer mortar.

    Science.gov (United States)

    Sathonsaowaphak, Apha; Chindaprasirt, Prinya; Pimraksa, Kedsarin

    2009-08-30

    In this paper, the waste lignite bottom ash from power station was used as a source material for making geopolymer. Sodium silicate and sodium hydroxide (NaOH) were used as liquid for the mixture and heat curing was used to activate the geopolymerization. The fineness of bottom ash, the liquid alkaline/ash ratio, the sodium silicate/NaOH ratio and the NaOH concentration were studied. The effects of the additions of water, NaOH and napthalene-based superplasticizer on the workability and strength of the geopolymer mortar were also studied. Relatively high strength geopolymer mortars of 24.0-58.0 MPa were obtained with the use of ground bottom ash with 3% retained on sieve no. 325 and mean particle size of 15.7 microm, using liquid alkaline/ash ratios of 0.429-0.709, the sodium silicate/NaOH ratios of 0.67-1.5 and 7.5-12.5M NaOH. The incorporation of water improved the workability of geopolymer mortar more effectively than the use of napthalene-based superplasticizer with similar slight reduction in strengths. The addition of NaOH solution slightly improves the workability of the mix while maintaining the strength of the geopolymer mortars.

  3. The Use of Coal Bottom Ash In Hot Mix Asphalt

    Directory of Open Access Journals (Sweden)

    Charles Begyina Kodjo Nketsiah

    2015-05-01

    Full Text Available Bottom ash is a waste material from coal burnt to generate electric power. It is incombustible and non-biodegradable; hence, the best way to dispose it is by recycling rather than incineration and land filling. Past research on bottom ash in road building have focused mainly on embankment filling, sub-base and base courses; except boiler slag which has received much attention in Hot Mix Asphalt (HMA. Bottom ash from Tanjung Bin Power Station was thus investigated through laboratory testing to justify its use in HMA construction in Malaysia. This Paper analysed the data with regards to performance in HMA. In the Marshall Mix design, the material largely satisfied the Stability, Flow and Stiffness requirements which were comparable to that of conventional aggregates, although void contents were a bit higher. When blended with granite, all the parameters were met. Contrary to past suggestions that bottom ash in HMA consumes more bitumen, the 6.4% (51.20g Optimum Bitumen Content (OBC achieved in this study does not necessarily translate into high consumption, compared to OBC of 5.3% (59.63g in the case of granite. The HMA also proved to be highly resistant to moisture-induced damage and satisfied the minimum JKR specification for Static Uniaxial Load Strain.

  4. Speciation of Chromium in Bottom Ash Obtained by the Incineration of the Leather Waste Shavings

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    k. louhab

    2006-01-01

    Full Text Available The evolution of bottom ash morphology and chromium metals behavior during incineration of a leather waste shavings at different incineration temperature have been studied. The Cr, Ca, Mg, Cl rates in bottom ashes, flay ashes and emitted gases in different incineration temperature of the tannery wastes are also determined. The morphology of the bottom ashes obtained by incineration at different temperature from the leather waste shavings was examined by MEB. The result show that the temperature and the length of incineration influence on the structure of the bottom ash and on the chromium in the bottom ash.

  5. Effect of fuel properties on the bottom ash generation rate by a laboratory fluidized bed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Rozelle, P.L.; Pisupati, S.V.; Scaroni, A.W. [Penn State University, University Park, PA (United States). Dept. of Energy & Geoenvironmental Engineering

    2007-06-15

    The range of fuels that can be accommodated by an FBC boiler system is affected by the ability of the fuel, sorbent, and ash-handling equipment to move the required solids through the boiler. Of specific interest is the bottom ash handling equipment, which must have sufficient capacity to remove ash from the system in order to maintain a constant bed inventory level, and must have sufficient capability to cool the ash well below the bed temperature. Quantification of a fuel's bottom ash removal requirements can be useful for plant design. The effect of fuel properties on the rate of bottom ash production in a laboratory FBC test system was examined. The work used coal products ranging in ash content from 20 to 40+ wt. %. The system's classification of solids by particle size into flyash and bottom ash was characterized using a partition curve. Fuel fractions in the size range characteristic of bottom ash were further analyzed for distributions of ash content with respect to specific gravity, using float sink tests. The fuel fractions were then ashed in a fixed bed. In each case, the highest ash content fraction produced ash with the coarsest size consist (characteristic of bottom ash). The lower ash content fractions were found to produce ash in the size range characteristic of flyash, suggesting that the high ash content fractions were largely responsible for the production of bottom ash. The contributions of the specific gravity fractions to the composite ash in the fuels were quantified. The fuels were fired in the laboratory test system. Fuels with higher amounts of high specific gravity particles, in the size ranges characteristic of bottom ash, were found to produce more bottom ash, indicating the potential utility of float sink methods in the prediction of bottom ash removal requirements.

  6. 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.

  7. Lipid peroxidation and oxidative status compared in workers at a bottom ash recovery plant and fly ash treatment plants.

    Science.gov (United States)

    Liu, Hung-Hsin; Shih, Tung-Sheng; Chen, I-Ju; Chen, Hsiu-Ling

    2008-01-01

    Fly ash and ambient emissions of municipal solid waste incinerators contain polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAHs), other organic compounds, metals, and gases. Hazardous substances such as PCDD/Fs, mercury vapors and other silicates, and the components of bottom ash and fly ash elevate the oxidative damage. We compared oxidative damage in workers exposed to hazardous substances at a bottom ash recovery plant and 3 fly ash treatment plants in Taiwan by measuring their levels of plasma malondialdehyde (MDA) and urine 8-hydroxydeoxyguanosine (8-OH-dG). Significantly higher MDA levels were found in fly ash treatment plant workers (3.20 microM) than in bottom ash plant workers (0.58 microM). There was a significant association between MDA levels in workers and their working environment, especially in the fly ash treatment plants. Levels of 8-OH-dG varied more widely in bottom ash workers than in fly ash workers. The association between occupational exposure and 8-OH-dG levels may be affected by the life style of the workers. Because more dioxins and metals may leach from fly ash than from bottom ash, fly ash treatment plant workers should, as much as possible, avoid exposing themselves to fly ash.

  8. 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.

  9. 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...

  10. Occupational exposure and DNA strand breakage of workers in bottom ash recovery and fly ash treatment plants.

    Science.gov (United States)

    Chen, Hsiu-Ling; Chen, I-Ju; Chia, Tai-Pao

    2010-02-15

    Various environmental hazards and metals are liberated either into bottom ash or carried away with gases and subsequently trapped in fly ash. Many studies have reported an increase of DNA damage is related to hazardous exposure of municipal waste incinerators. By detecting DNA damage, we compared the DNA migration imposed in workers potentially exposed to hazardous substances, including PCDD/Fs, metals, and silica particles, at a bottom ash recovery plant and fly ash treatment plants in Taiwan. Higher tail moment (TMOM) was found in workers at fly ash treatment plants (7.55) than in the workers in bottom ash plants (2.64), as well as those in blue collar was higher than in white collar workers (5.72 vs. 3.95). Meanwhile, the significantly higher DNA damage was also shown in workers with high integrated exposure score than those with low. The air samplings for particle mass, Cr, and Al concentrations also showed the higher levels in fly ash treatment plants than in the workers in bottom ash plants. Meanwhile, the air samplings inside the two plants suggested that the particle size might be important to affect the workers inhaling the metal into the human body and finally caused to their DNA damage. The data concluded that an elevated DNA damage may be expected in workers at fly ash treatment plants than those at bottom ash plants; however, the occupational hazards in both types of plants, especially at different particle size interval, need more thorough assessment in future studies.

  11. Physical and Chemical Properties of Coal Bottom Ash (CBA) from Tanjung Bin Power Plant

    Science.gov (United States)

    Izzati Raihan Ramzi, Nurul; Shahidan, Shahiron; Zulkhairi Maarof, Mohamad; Ali, Noorwirdawati

    2016-11-01

    The objective of this study is to determine the physical and chemical characteristics of Coal Bottom Ash (CBA) obtained from Tanjung Bin Power Plant Station and compare them with the characteristics of natural river sand (as a replacement of fine aggregates). Bottom ash is the by-product of coal combustion during the electricity generating process. However, excess bottom ash production due to the high production of electricity in Malaysia has caused several environmental problems. Therefore, several tests have been conducted in order to determine the physical and chemical properties of bottom ash such as specific gravity, density, particle size distribution, Scanning Electron Microscopic (SEM) and X- Ray Fluorescence (XRF) in the attempt to produce sustainable material from waste. The results indicated that the natural fine aggregate and coal bottom ash have very different physical and chemical properties. Bottom ash was classified as Class C ash. The porous structure, angular and rough texture of bottom ash affected its specific gravity and particle density. From the tests, it was found that bottom ash is recommended to be used in concrete as a replacement for fine aggregates.

  12. Greenlandic Waste Incineration Fly And Bottom Ash As Secondary Resource In Mortar

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.; Jensen, Pernille Erland

    2016-01-01

    Today, 900 tons incineration fly ash is shipped abroad annually from Greenland for deposits, whereas the 6,000 tons incineration bottom ash is deposited locally. These incineration ashes could be valuable in concrete production, where the cement has to be shipped to Greenland. For this purpose...... and cement with fly ash. Based on the compressive strength tests, it is found that using Greenlandic incineration ashes in mortar as 5% cement replacement could consume all ash instead of disposals, and could thus turn the ashes into a local resource and simultaneously reduce the import of cement....

  13. Utilization of Meat and Bone Meal Bottom Ash in Ceramics

    Directory of Open Access Journals (Sweden)

    Virginija VALANČIENĖ

    2011-03-01

    Full Text Available During utilization of animal waste meat and bone meal (MBM is received, realization and use of which has been stopped due to risk for the transmission of the bovine spongiform encephalopathy infection. The MBM must be safely stored or treated. Most often meat and bone meal undergoes thermal treatment. During combustion large quantities of residues (ashes are received, the recycled use of which has been given a lot of attention lately. In this work it was investigated the impact of the additive of the bottom ash (BA formed during combustion of the MBM on the properties of forming mass and ceramic body of hydromica clay, and also it was evaluated a possibility to use the MBM BA in manufacturing of building ceramics. After replacing the sand in porous ceramics by this additive the plasticity of the forming mass, drying and firing shrinkage as well as density of ceramic body changed insignificantly whereas the compressive strength increased by 8 % - 22 %. So the MBM BA can be utilized in production of porous ceramics.http://dx.doi.org/10.5755/j01.ms.17.1.256

  14. Utilization of Meat and Bone Meal Bottom Ash in Ceramics

    Directory of Open Access Journals (Sweden)

    Virginija VALANČIENĖ

    2011-03-01

    Full Text Available During utilization of animal waste meat and bone meal (MBM is received, realization and use of which has been stopped due to risk for the transmission of the bovine spongiform encephalopathy infection. The MBM must be safely stored or treated. Most often meat and bone meal undergoes thermal treatment. During combustion large quantities of residues (ashes are received, the recycled use of which has been given a lot of attention lately. In this work it was investigated the impact of the additive of the bottom ash (BA formed during combustion of the MBM on the properties of forming mass and ceramic body of hydromica clay, and also it was evaluated a possibility to use the MBM BA in manufacturing of building ceramics. After replacing the sand in porous ceramics by this additive the plasticity of the forming mass, drying and firing shrinkage as well as density of ceramic body changed insignificantly whereas the compressive strength increased by 8 % - 22 %. So the MBM BA can be utilized in production of porous ceramics.http://dx.doi.org/10.5755/j01.ms.17.1.256

  15. Modeling the formation of the quench product in municipal solid waste incineration (MSWI) bottom ash.

    Science.gov (United States)

    Inkaew, Kanawut; Saffarzadeh, Amirhomayoun; Shimaoka, Takayuki

    2016-06-01

    This study investigated changes in bottom ash morphology and mineralogy under lab-scale quenching conditions. The main purpose was to clarify the mechanisms behind the formation of the quench product/layer around bottom ash particles. In the experiments, the unquenched bottom ashes were heated to 300°C for 1h, and were quenched by warm water (65°C) with different simulated conditions. After having filtered and dried, the ashes were analyzed by a combination of methodologies namely, particle size distribution analysis, intact particle and thin-section observation, X-ray diffractometry, and scanning electron microscope with energy dispersive X-ray spectroscopy. The results indicated that after quenching, the morphology and mineralogy of the bottom ash changed significantly. The freshly quenched bottom ash was dominated by a quench product that was characterized by amorphous and microcrystalline calcium-silicate-hydrate (CSH) phases. This product also enclosed tiny minerals, glasses, ceramics, metals, and organic materials. The dominant mineral phases produced by quenching process and detected by XRD were calcite, Friedel's salt, hydrocalumite and portlandite. The formation of quench product was controlled by the fine fraction of the bottom ash (particle size ash-water reactions and formation of the quench product in the bottom ash was proposed.

  16. Synthesis and characterization of geopolymer from bottom ash and rice husk ash

    Science.gov (United States)

    Anggarini, Ufafa; Sukmana, Ndaru C.

    2016-02-01

    All Geopolymer (GP) has been synthesized from bottom ash and rice husk ash. This research aims to determine the effect of Si/Al ratio on geopolymer synthesis. Geopolymer was synthesized with various Si/Al ratio of 2, 3 and 4. The characterization result using XRD and SEM indicated that by using a different ratio of Si/A, it will produce geopolymer with varied structure and morphology. Diffractogram result shows that polymerization has been done for all samples (GP2, GP3, Gp4) with the presence of hump peak at 2θ = 27-35°. In GP4, no peak at 2θ = 18° indicating sodalite phase forming. Besides that, the morphology of geopolymer with a varied ratio of Si/Al shows that higher ratio will produce geopolymer with higher particle size. The highest compressive strength of geopolymer was obtained at a ratio of Si/Al = 4, with a maximum load of 12866 kgf.

  17. Contribution of natural organic matter to copper leaching from municipal solid waste incinerator bottom ash

    NARCIS (Netherlands)

    Zomeren, van A.; Comans, R.N.J.

    2004-01-01

    The leaching of heavy metals, such as copper, from municipal solid waste incinerator (MSWI) bottom ash is a concern in many countries and may inhibit the beneficial reuse of this secondary material. The enhanced leaching of copper from three MSWI bottom ash samples by dissolved organic carbon (DOC)

  18. Adsorption of organic pollutants from coking and papermaking wastewaters by bottom ash

    Energy Technology Data Exchange (ETDEWEB)

    Sun Weiling [Department of Environmental Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871 (China)], E-mail: sunweiling@iee.pku.edu.cn; Qu Yanzhi; Yu Qing; Ni Jinren [Department of Environmental Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871 (China)

    2008-06-15

    Bottom ash, a power plant waste, was used to remove the organic pollutants in coking wastewater and papermaking wastewater. Particular attention was paid on the effect of bottom ash particle size and dosage on the removal of chemical oxygen demand (COD). UV-vis spectra, fluorescence excitation-emission matrix (FEEM) spectra, Fourier transform infrared (FTIR) spectra, and scanning electron microscopic (SEM) photographs were investigated to characterize the wastewaters and bottom ash. The results show that the COD removal efficiencies increase with decreasing particle sizes of bottom ash, and the COD removal efficiency for coking wastewater is much higher than that for papermaking wastewater due to its high percentage of particle organic carbon (POC). Different trends of COD removal efficiency with bottom ash dosage are also observed for coking and papermaking wastewaters because of their various POC concentrations. Significant variations are observed in the FEEM spectra of wastewaters after treatment by bottom ash. New excitation-emission peaks are found in FEEM spectra, and the fluorescence intensities of the peaks decrease. A new transmittance band in the region of 1400-1420 cm{sup -1} is observed in FTIR spectra of bottom ash after adsorption. The SEM photographs reveal that the surface of bottom ash particles varies evidently after adsorption.

  19. Impact of separated bottom ashes on the parameters of concrete mix and hardened concrete

    Directory of Open Access Journals (Sweden)

    Wałach Daniel

    2016-01-01

    This paper analyses the impact of the addition of bottom ashes obtained from hard coal combustion in conventional and fluidised bed boilers on the properties of fresh and hardened concrete. A concrete mix composition was developed by an experimental method, which was then modified with the use of bottom ashes. The impact of the substitution of cement and aggregates with bottom ash on the concrete properties was examined. For all the obtained series of concretes, tests were performed for the consistency of the fresh concrete using the concrete slump test, the compressive strength and tensile strength of the concrete after 3, 7 and 28 days of maturing and their absorption. The experiments have shown significant declines in the strength parameters of the concretes being analysed in the case of the substitution of cement with separated bottom ash. However, substituting relevant aggregate fractions with separated bottom ash resulted in an increase in both the compressive strength and the tensile strength in the analysed concretes.

  20. Comparison of various bioassays for dioxins measurements in fuel gas, fly ash and bottom ash

    Energy Technology Data Exchange (ETDEWEB)

    Ota, S.; Kin-ichi, S. [Ministry of the Environment, Tokyo (Japan); Masatoshi, M.; Shin-ichi, S. [National Institute for Environmental Studies, Tsukuba (Japan)

    2004-09-15

    In Japan, the control standards for dioxins (PCDDs, PCDFs and Co-PCBs) in the emission gas, fly and bottom ashes from waste incinerators have been defined in the Law Concerning Special Measures against Dioxins (Dioxins Law). Based on the Dioxins law, an installation personnel of waste incinerators of specified facilities shall measure dioxins in the emission gas and fly and bottom ashes more than once every year followed by reporting the results to their prefectural governor. The present regulating procedure has been set to use high-resolution gas chromatography/ high-resolution mass spectrometry (HRGC/HRMS, hereafter GC/MS) systems to determine dioxin-concentrations. However, the GC/MS measurements are often money- and timeconsuming, since they need complicated steps for sample preparation, expensive equipments and highly skilled technicians. Therefore, it is of high priority to develop rapid and economical alternative methods to measure dioxins. Recently, various assays using biological reactions have drawn a high degree of attention as a candidate for alternative measurement methods of dioxins. During the past decade several studies demonstrated the utility of a chemical (GC/MS) and biological (bioassays/biomarkers) control of waste thermal recycling processes like pyrolysis or incineration treatment. In this paper, we report the results of our recent examinations on the possibility to apply various bioassays to supplementary methods for the present procedure.

  1. Properties of Concrete using Tanjung Bin Power Plant Coal Bottom Ash and Fly Ash

    Directory of Open Access Journals (Sweden)

    Abdulhameed Umar Abubakar

    2012-12-01

    Full Text Available Coal combustion by-products (CCPs have been around since man understood that burning coal generates electricity, and its utilization in concrete production for nearly a century. The concept of sustainable development only reawaken our consciousness to the huge amount of CCPs around us and the need for proper reutilization than the current method of disposal which has  severe consequences both to man and the environment. This paper presents the result of utilization of waste from thermal power plants to improve some engineering properties of concrete. Coal bottom ash (CBA and fly ash were utilized in partial replacement for fine aggregates and cement respectively. The results of compressive strength at 7, 28, 56 & 90 days curing are presented because of the pozzolanic reaction. Other properties investigated include physical properties, fresh concrete properties and density. The results showed that for a grade 35 concrete with a combination of CBA and fly ash can produce 28 day strength above 30 MPa.

  2. 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

  3. Stabilisation of MSWI bottom ash with sulphide-rich anaerobic effluent.

    Science.gov (United States)

    Sivula, Leena; Väisänen, Ari; Rintala, Jukka

    2008-03-01

    Effluent of an anaerobic sulphate-reducing wastewater treatment process was used to stabilise bottom ash. The effect of stabilisation on the concentration and binding of Ca, P, S, Cu, Pb, Zn, As, Cr, and Mo were studied by comparing results of sequential extraction from fresh and stabilised bottom ash. The stabilisation treatment improved the retention of Ca, Cu, Pb, S, and Zn in bottom ash compared to a treatment with ion-exchanged water. In addition to retention, Cu, S, and Zn were accumulated from the anaerobic effluent in the bottom ash. Concentrations of As, Cr, and Mo remained on the same level, whereas leaching of P increased compared to control treatment with ion-exchanged water. Improved retention and accumulation were the result of increased binding to less soluble fractions. The highest increases were in the sulphide and organic carbon bound fraction and in the carbonate fraction. Enhanced carbonation was probably due to CO2 deriving from the degradation of organic carbon. Flushing of stabilised bottom ash with ion-exchanged water ensured that the observed changes were not easily reversed. Most of the sulphide in the anaerobic effluent was removed when it was passed through bottom ash. The objective was to study the feasibility of sulphide-rich anaerobic effluent in bottom ash stabilisation and changes in the binding of the elements during stabilisation. In addition, the ability of the process to remove sulphide from the effluent was observed.

  4. Eco-friendly porous concrete using bottom ash aggregate for marine ranch application.

    Science.gov (United States)

    Lee, Byung Jae; Prabhu, G Ganesh; Lee, Bong Chun; Kim, Yun Yong

    2016-03-01

    This article presents the test results of an investigation carried out on the reuse of coal bottom ash aggregate as a substitute material for coarse aggregate in porous concrete production for marine ranch applications. The experimental parameters were the rate of bottom ash aggregate substitution (30%, 50% and 100%) and the target void ratio (15%, 20% and 25%). The cement-coated granular fertiliser was substituted into a bottom ash aggregate concrete mixture to improve marine ranch applications. The results of leaching tests revealed that the bottom ash aggregate has only a negligible amount of the ten deleterious substances specified in the Ministry of Environment - Enforcement Regulation of the Waste Management Act of Republic Korea. The large amount of bubbles/air gaps in the bottom ash aggregate increased the voids of the concrete mixtures in all target void ratios, and decreased the compressive strength of the porous concrete mixture; however, the mixture substituted with 30% and 10% of bottom ash aggregate and granular fertiliser, respectively, showed an equal strength to the control mixture. The sea water resistibility of the bottom ash aggregate substituted mixture was relatively equal to that of the control mixture, and also showed a great deal of improvement in the degree of marine organism adhesion compared with the control mixture. No fatality of fish was observed in the fish toxicity test, which suggested that bottom ash aggregate was a harmless material and that the combination of bottom ash aggregate and granular fertiliser with substitution rates of 30% and 10%, respectively, can be effectively used in porous concrete production for marine ranch application.

  5. Sustainability assessment and prioritisation of bottom ash management in Macao.

    Science.gov (United States)

    Sou, W I; Chu, Andrea; Chiueh, P T

    2016-12-01

    In Macao, about 7200 t yr(-1) of bottom ash (BA) is generated and conventionally landfilled with construction waste. Because the properties of BA are similar to those of natural aggregates, it is suitable to be recycled as construction material. However, pre-treatment processes for BA reuse may require more resource input and may generate additional environmental impacts. Life cycle assessment, multi-media transport model analysis, cost-benefit analysis and the analytical hierarchy process were conducted to evaluate the impacts of current and potential BA management scenarios regarding environmental, economic, social and regulatory aspects. The five analysed scenarios are as follows: (0) BA buried with construction and demolition waste (current system); (1) pre-treated BA used to replace 25% of the natural aggregate in asphalt concrete; (2) pre-treated BA used to replace 25% of the natural aggregate in cement concrete; (3) pre-treated BA used to replace 25% of cement in cement concrete; and (4) pre-treated BA sent to China, blended with municipal solid waste for landfill. The results reveal the following ranking of the scenarios: 3 > 2 > 0 > 1 > 4. Scenario 3 shows the best conditions for BA recycling, because the quantity of cement concrete output is the highest and this brings the greatest economic benefits. Our use of integrated analysis provides multi-aspect investigations for BA management systems, particularly in accounting for site-specific characteristics. This approach is suitable for application in other non-western regions. © The Author(s) 2016.

  6. Co-sintering of treated APC-residues with bottom ash

    DEFF Research Database (Denmark)

    Bergfeldt, B.; Jensen, Dorthe Lærke; Vehlow, J.;

    2001-01-01

    the influence of co-sintering of Ferrox products with bottom ashes on the quality of the residues and the effects on the combustion process. Only few elements showed higher concentrations in the bottom ashes of these co-combustion tests compared to reference tests. No significant effect on the leaching...... behaviour of the bottom ashes could be found. During the co-combustion process an increase in SO2 concentrations in the raw gas and slightly lower temperatures in the fuel bed could be observed....

  7. Long-term Performance of MSWI Bottom Ash in a Test Road Construction

    OpenAIRE

    Paul Christian Frogner-Kockum; Jan Erik Lindqvist

    2016-01-01

    The study focuses on long-term performances of MSWI bottom ash used as a reinforcement layer in a 8 years old road-construction. Long term properties may change under the combined effects of loading, climate- and chemical conditions. Characterization of the chemical changes in aged MSWI bottom ash is thus of prime interest as secondary alteration is a key process for the ageing of these kind of materials. The MSWI bottom ash in this study comprises a 60 meter-long segment of a test road, whic...

  8. Solidification/stabilization of fly and bottom ash from medical waste incineration facility.

    Science.gov (United States)

    Anastasiadou, Kalliopi; Christopoulos, Konstantinos; Mousios, Epameinontas; Gidarakos, Evangelos

    2012-03-15

    In the present work, the stabilization/solidification of fly and bottom ash generated from incinerated hospital waste was studied. The objectives of the solidification/stabilization treatment were therefore to reduce the leachability of the heavy metals present in these materials so as to permit their disposal in a sanitary landfill requiring only a lower degree of environmental protection. Another objective of the applied treatment was to increase the mechanical characteristics of the bottom ash using different amounts of Ordinary Portland Cement (OPC) as a binder. The solidified matrix showed that the cement is able to immobilize the heavy metals found in fly and bottom ash. The TCLP leachates of the untreated fly ash contain high concentrations of Zn (13.2 mg/l) and Pb (5.21 mg/l), and lesser amounts of Cr, Fe, Ni, Cu, Cd and Ba. Cement-based solidification exhibited a compressive strength of 0.55-16.12 MPa. The strength decreased as the percentage of cement loading was reduced; the compressive strength was 2.52-12.7 MPa for 60% cement mixed with 40% fly ash and 6.62-16.12 MPa for a mixture of 60% cement and 40% bottom ash. The compressive strength reduced to 0.55-1.30 MPa when 30% cement was mixed with 70% fly ash, and to 0.90-7.95 MPa when 30% cement was mixed with 70% bottom ash, respectively. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Trace element geochemistry of feed coal, fly and bottom ashes of Turkish power plants: implications for ash utilisation

    Energy Technology Data Exchange (ETDEWEB)

    Gayer, R.A.; Karayigit, A.I.; Goldsmith, S.; Onacak, T.; Rose, M. [Cardiff University, Cardiff (United Kingdom). Dept of Earth Sciences

    1998-12-31

    Recent environmental concern has led to studies of the fate of environmentally sensitive elements (ESEs) during the combustion of coal in power plants. Of particular interest has been the partioning of potentially hazardous trace elements in coal-combustion waste products (fly ash and bottom ash) and in flue gases. This paper reports on a preliminary investigation into the trace element geochemistry of feed coals, bottom ash and fly ash in thirteen power units in Turkey. It concentrates on sixteen trace elements, five of which are of major environmental concern (Be, As, Mo, Pb, and Tl), two of moderate concern (Cu and Zn), three of minor concern (Mn, Co and Ba). Two of the ESEs are radiogenic (Th and U). Ti, Cs, La, and W, which show interesting distributions, are also considered. The approach has been to analyse the feed coals to highlight any significant element enrichment and to carry out mass balance calculations to determine the partioning of elements between bottom and fly ash. Results indicate that solid residues, particularly fly ash may show unusually high concentrations of moderately volatile ESEs such as As, Pb, Tl, Mo, Be and Zn. The use of such enriched fly ash should be treated with caution. 9 refs., 2 figs., 3 tabs.

  10. Characterization of bottom ashes from coal pulverized power plants to determine their potential use feasibility

    Energy Technology Data Exchange (ETDEWEB)

    Menendez, E.; Alvaro, A. M.; Argiz, C.; Parra, J. L.; Moragues, A.

    2013-07-01

    The disposal of coal by products represents environmental and economical problems around the world. Therefore, the reuse and valorisation of this waste has become an important issue in the last decades. While high-value construction products containing fly ash were developed and its use is actually totally accepted as an addition to cement, the use of the bottom ash as supplementary cementitious material has not been allow. This paper examines the chemical and physical properties of fly ashes and bottom ashes from two different coal power plants in order to compare them and analyse the potential feasibility of bottom ash as cement replacement. The mechanical properties of cement mortars made with different percentages of both ashes were also study. The results obtained showed similar chemical composition of both kinds of ashes. The compressive strength values of mortars with 10 % and 25 % of cement replacement (at 28 days) were above the limits established in European standards and there were not significant differences between fly ash and bottom ash from both origins. (Author)

  11. [Research on degradation of methylene blue by coal bottom ash-microwave irradiation method].

    Science.gov (United States)

    Wu, Shi-Wei; Li, Na; Li, Guang-Zhe; Li, Guo-De

    2010-05-01

    Coal bottom ash is rich in metals and transition metals, and with microwave irradiation these metals can effectively degradate organic matter. Methylene blue degradation by coal bottom ash-microwave irradiation mainly through hydroxyl radicals to degrade organic matter, and metals and rare metals in bottom ash can be used as a catalyst for deep oxidation of organic matter, can reduce processing costs, and reduce environmental pollution. In the present paper the main parameters including the amount of coal bottom ash, H2O2 dosage and time of microwave irradiation were investigated. The UV-visible spectra of methylene blue were determined. The results show that: under coal bottom ash and H2O2 microwave condition the degeneration rate of methylene blue was almost 100%. The dosage of coal ash can accelerate the reaction process, speeding up the degradation of methylene blue. The increase of H2O2 may provide more * OH and speed up the reaction process, but when up to a certain amount, the influence is weakened. The lengthening of microwave time may enhance the reaction temperature, and urge the methylene blue to degrade completely. For 0.125 g x L(-1) of methylene blue, by adding 1.0 g coal bottom ash, 5 mL H2O2 and under mesotherm microwave temperature for 4 min, the methylene blue can be all degradated.

  12. Leaching behavior of polychlorinated dibenzo-p-dioxins and furans from the fly ash and bottom ash of a municipal solid waste incinerator.

    Science.gov (United States)

    Yasuhara, Akio; Katami, Takeo

    2007-01-01

    The leaching behavior of dioxins from landfill containing bottom ash and fly ash from municipal solid waste incineration has been investigated by leaching tests with pure water, non-ionic surfactant solutions, ethanol solutions, or acetic acid solutions as elution solvents for a large-scale cylindrical column packed with ash. Larger amounts of dioxins were eluted from both bottom ash and fly ash with ethanol solution and acetic acid solution than with pure water. Large quantities of dioxins were leached from fly ash but not bottom ash by non-ionic surfactant solutions. The patterns of distribution of the dioxin congeners in the leachates were very similar to those in the bottom ash or fly ash from which they were derived.

  13. Copper speciation in municipal solid waste incinerator bottom ash leachates; Kopparformer i lakvatten fraan energiaskor

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Susanna; Gustafsson, Jon Petter [Royal Inst. of Tech., Stockholm (Sweden); Schaik, Joris van; Berggren Kleja, Dan [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden); Hees, Patrick van [Oerebro Univ. (Sweden)

    2006-03-15

    The formation of copper (Cu) complexes with dissolved organic carbon (DOC) in bottom ash from municipal solid waste incineration (MSWI) may increase the total amount of Cu released but at the same time reduce its toxicity. In this study, DOC in a MSWI bottom ash leachate was characterized and the Cu-binding properties of different DOC fractions in the ash leachate and in a soil solution were studied. This knowledge may be used for improved environmental assessment of MSWI bottom ash in engineering applications. The Cu{sup 2+} activity at different pH values was measured potentiometrically using a Cu-ion selective electrode (Cu-ISE). Experimental copper complexation results were compared to speciation calculations made in Visual MINTEQ with the NICA-Donnan model and the Stockholm Humic Model (SHM). The MSWI bottom ash leachate contained a larger proportion of hydrophilic organic carbon than the investigated soil solution and other natural waters. The hydrophilic fraction of both samples showed Cu{sup 2+} binding properties similar to that of the bulk, cation-exchanged, leachate. For the ash leachate, the pH dependence of the Cu activity was not correctly captured by neither the SHM nor the NICA-Donnan model, but for the soil solution the model predictions of Cu speciation were in good agreement with the obtained results. The complex formation properties of the ash DOC appears to be less pH-dependent than what is assumed for DOC in natural waters. Hence, models calibrated for natural DOC may give inconsistent simulations of Cu-DOC complexation in MSWI bottom ash leachate. A Biotic Ligand Model for Daphnia Magna was used to provide an estimate of the copper concentrations at LC50 for a simulated bottom ash leachate. It was concluded that the Cu concentrations in certain bottom ash leachates are high enough to pose an ecotoxicological risk; however, after dilution and soil sorption, the risks for neighboring water bodies are most likely negligible. Three processes were

  14. Treated bottom ash medium and method of arsenic removal from drinking water

    Science.gov (United States)

    Gadgil, Ashok

    2009-06-09

    A method for low-cost arsenic removal from drinking water using chemically prepared bottom ash pre-treated with ferrous sulfate and then sodium hydroxide. Deposits on the surface of particles of bottom ash form of activated iron adsorbent with a high affinity for arsenic. In laboratory tests, a miniscule 5 grams of pre-treated bottom ash was sufficient to remove the arsenic from 2 liters of 2400 ppb (parts per billion) arsenic-laden water to a level below 50 ppb (the present United States Environmental Protection Agency limit). By increasing the amount of pre-treated bottom ash, even lower levels of post-treatment arsenic are expected. It is further expected that this invention supplies a very low-cost solution to arsenic poisoning for large population segments.

  15. Quality assurance of MSWI bottom ash. Environmental properties; Kvalitetssaekring av slaggrus. Miljoemaessiga egenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, Peter [Lund Univ. (Sweden). Engineering Geology

    2006-04-15

    In Sweden, several hundred tonnes of MSWI bottom ash are generated annually at 29 incineration plants for municipal solid waste. So far bottom ash has mainly been disposed in to landfills or used as cover material in landfills or in other construction works at landfills. A few applications of bottom ash in construction works outside landfills have been reported. A large problem for the market of bottom ash and other secondary materials outside Swedish waste treatment plants is the lack of roles and regulations for a non-polluting use. During 2002 Hartlen and Groenholm presented a proposal to a system to assure the quality of bottom ash after homogenization and stabilization. They notice that the leaching of salts and metals to ground water constitutes the largest risk for the environment during use of bottom ash. Therefore, a quality assurance of environmental properties should be based on leaching tests. The aim of this project was to study how the control of environmental properties of bottom ash (at first hand leaching properties) earlier described in e.g. a product information sheet should be worked out. The starting-point has been a control system for bottom ash developed by Sysav. Different leaching tests illustrate however different aspects of the environmental properties, e.g. short-term and long-term leaching. Limit and target values for different variables could affect both the possibilities to use bottom ash as well as the sampling from storage heaps. We have chosen to investigate pH, availability and leached amount and the connection between these variables. the possibilities to use pH or the availability to assess both short-term and longterm leaching properties. how the number of subsamples that should be collected from a storage heap is affected by different control variables and quality requirements. how bottom ash is stabilized by today's storage technology and how the technology could be improved. Our sample test of bottom ash from Swedish

  16. Biogas--municipal solid waste incinerator bottom ash interactions: sulphur compounds removal.

    Science.gov (United States)

    Ducom, Gaëlle; Radu-Tirnoveanu, Daniela; Pascual, Christophe; Benadda, Belkacem; Germain, Patrick

    2009-07-30

    This study focuses on a new way of reusing municipal solid waste incinerator bottom ash: landfill gas purification before energetic valorisation. A pilot plant was designed and operated on a landfill site located in France (Loire). One kilogram bottom ash is able to sequestrate more than 3.0 g of hydrogen sulphide, 44 mg of methyl mercaptan, and 86 mg of dimethyl sulphide. Hydrogen sulphide retention is probably due to acid-basic reactions conducting to sulphur mineralisation under the form of low solubility metal sulphides. The reaction medium is hydration water. The retention mechanism for methyl mercaptan is probably similar but dimethyl sulphide is most likely retained by physical adsorption. As methane is not retained by bottom ash, the landfill gas energetic content will not be lowered. There seems to be no appreciable difference in these results whether bottom ash is fresh or carbonated. These results are encouraging in the perspective of a field scale application of this biogas treatment process.

  17. Comparison between laboratory and field leachability of MSWI bottom ash as a road material.

    Science.gov (United States)

    Izquierdo, Maria; Querol, Xavier; Josa, Alejandro; Vazquez, Enric; López-Soler, Angel

    2008-01-15

    The leaching properties of bottom ash from municipal solid waste incineration (MSWI) used as an aggregate substitute in unbound pavement layers are evaluated. The mechanical behaviour of bottom ash is acceptable for this application, but the potential environmental consequences constitute the most important limitation on the use of bottom ash as a road material. The environmental properties of bottom ash are assessed by means of the Dutch availability test NEN 7341 and the single-batch and two-stage batch European EN 12457 laboratory leaching tests. Furthermore, an experimental unbound pavement stretch is constructed to provide information on leaching behaviour under field conditions. In this high infiltration scenario, the results from predicted (based upon laboratory leaching tests) and measured releases (under field conditions) are compared, evidencing that predictions based on compliance leaching tests may be highly realistic. The depletion period of the extractable fraction of a number of elements in these field conditions is also quantified.

  18. Innovative use of recovered municipal solid waste incineration bottom ash as a component in growing media.

    Science.gov (United States)

    Sormunen, Annika; Teo, Kanniainen; Tapio, Salo; Riina, Rantsi

    2016-07-01

    The utilisation of municipal solid waste incineration bottom ash has been extensively studied, for example, in the unbound layers of roads and the products of cement and concrete industry. On the other hand, less attention has been given to other innovative utilisation possibilities, such as using the municipal solid waste incineration bottom ash as a component in growing media of plants. The municipal solid waste incineration bottom ash contains useful substances, such as calcium, that can influence plant growth in a positive manner. Therefore, the utilisation of this waste-derived material in the growing media may substitute the use of commercial fertilisers. Since the municipal solid waste incineration bottom ash also contains hazardous substances that can be toxic to plants, the main aim of this study was to add different amounts of recovered municipal solid waste incineration bottom ash in the growing media and to evaluate the effect of this material on plant growth. Based on the obtained results, the concentration of, for example copper and zinc, increased in test plants; ryegrass and barley, when recovered municipal solid waste incineration bottom ash was added in their growing media. On the other hand, this did not have a significant effect on plant growth, if compared with the growth of plants in commercially produced growing medium. Furthermore, the replacement of natural sand with municipal solid waste incineration bottom ash had a positive liming effect in the growing media. Overall, these findings suggest that the utilisation of recovered municipal solid waste incineration bottom ash as a component in growing media is possible and, thus, may allow more widespread and innovative use of this waste-derived material. © The Author(s) 2016.

  19. Removal of hydrogen sulfide gas and landfill leachate treatment using coal bottom ash.

    Science.gov (United States)

    Lin, C Y; Hesu, P H; Yang, D H

    2001-06-01

    Coal bottom ashes produced from three thermal power plants were used in column and batch experiments to investigate the adsorption capacity of the coal ash. Hydrogen sulfide and leachates collected from three sanitary landfill sites were used as adsorbate gas and solutions, respectively. Experimental results showed that coal bottom ash could remove H2S from waste gas or reduce the concentrations of various pollutants in the leachate. Each gram of bottom ash could remove up to 10.5 mg of H2S. In treating the landfill leachate, increasing ash dosage increased the removal efficiency but decreased the adsorption amount per unit mass of ash. For these tested ashes, the removal efficiencies of chemical oxygen demand (COD), NH3-N, total Kjeldhal nitrogen (TKN), P, Fe3+, Mn2+, and Zn2+ were 36.4-50, 24.2-39.4, 27.0-31.1, 82.2-92.9, 93.8-96.5, 93.7-95.4, and 80.5-82.2%, respectively; the highest adsorption capacities for those parameters were 3.5-5.6, 0.22-0.63, 0.36-0.45, 0.027-0.034, 0.050-0.053, 0.029-0.032, and 0.006 mg/g of bottom ash, respectively. The adsorption of pollutants in the leachate conformed to Freundlich's adsorption model.

  20. Use of Coal Bottom Ash as Mechanical Stabiliser in Subgrade Soil

    Directory of Open Access Journals (Sweden)

    Abdus Salaam Cadersa

    2014-01-01

    Full Text Available This paper presents the laboratory investigation work which forms part of a full scale research road project in Mauritius where coal bottom ash is used as mechanical stabiliser in a saprolitic subgrade soil. Three mixtures of subgrade soil and CBA were investigated in the laboratory, each containing varying percentages of coal bottom ash by weight (15%, 30%, and 40%, resp.. The laboratory research indicated that the mechanical properties of the subgrade soil are improved with the addition of bottom ash. Highest values for soaked and unsoaked CBR values were obtained for the mixture containing 30% by weight of bottom ash, which were 145% and 95%, respectively, as compared to 40% and 55% for the subgrade soil alone. Upon addition of coal bottom ash, a considerable decrease in swelling potential during soaking was observed for the mixture containing 40% by weight of CBA. The swell decreased from 0.17% for the subgrade soil alone to 0.04% for the mixture containing 40% by weight of CBA. Moreover, a CBA content of 30% resulted in a mix of intermediate plasticity as compared to the subgrade soil which is highly plastic. It is concluded that coal bottom ash can be used successfully as a mechanical stabilizer in the experimental subgrade soil by addition of 30 to 40% of CBA.

  1. Quality assurance of MSWI bottom ash. Environmental properties; Kvalitetssaekring av slaggrus. Miljoemaessiga egenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, Peter [Lund Univ. (Sweden). Dept. of Engineering Geology

    2006-04-15

    In Sweden several hundred tonnes of MSWI bottom ash are generated annually at 29 incineration plants for municipal solid waste. So far bottom ash has mainly been disposed in to landfills or used as cover material in landfills or in other construction works at landfills. A few applications of bottom ash in construction works outside landfills have been reported. A large problem for the market of bottom ash and other secondary materials outside Swedish waste treatment plants is the lack of roles and regulations for a non-polluting use. During 2002 Hartlen and Groenholm (HG) presented a proposal to a system to assure the quality of bottom ash after homogenization and stabilization. A quality assurance of environmental properties should be based on leaching tests. The aim of this project was to study how the control of environmental properties of bottom ash earlier described in e.g. a product information sheet should be worked out. The starting-point has been a control system for bottom ash developed by the Sysav company. Different leaching tests illustrate however different aspects of the environmental properties, e.g. short-term and long-term leaching. Limit and target values for different variables could affect both the possibilities to use bottom ash as well as the sampling from storage heaps. We have chosen to investigate: pH, availability and leached amount and the connection between these variables; the possibilities to use pH or the availability to assess both short-term and long term leaching properties; how the number of subsamples that should be collected from a storage heap is affected by different control variables and quality requirements; how bottom ash is stabilized by today's storage technology and how the technology could be improved. Our sample test of bottom ash from Swedish incineration plants indicates that the availability of elements such as Cd, Cu, Cr, Ni, Pb and Zn in bottom ash usually is below Sysav's target values. Extreme values

  2. Free swell characteristics of PCC bottom ash-bentonite mixtures with curing for use as fill or liner material

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S.; Burrus, N. [South Illinois University, Carbondale, IL (United States). Dept. for Civil & Environmental Engineering

    2005-07-01

    Bottom ash is a coal combustion product (CCP) obtained from burning of pulverized coal to produce electricity. Most of the bottom ash from pulverized coal combustion (PCC) plants is disposed of in landfills and/or ash ponds. Over the last decade, there has been increased attention aimed toward the use of PCC bottom ash in geotechnical applications. The particle size distribution of pulverized coal combustion (PCC) bottom ash is similar to that of natural sand. Naturals and is commonly used in the construction industry in place of cohesive soils by adding admixtures to amend its properties. Several studies have been completed to determine the properties of bottom ash amended with bentonite. However, due to significant volume change characteristics of bentonite, soils or similar granular materials amended with it need to be evaluated for their swelling behavior. In addition, studies all bottom ash-bentonite mixtures have shown that strength and stiffness characteristics of these mixtures change significantly with curing. Therefore, in order to evaluate the use of bottom ash as a fill or landfill liner material, this study was initiated to investigate the effect of curing and moisture content on the swelling: characteristics of pulverized coal combustion bottom ash amended with bentonite. Bottom ash specimens containing 15 and 20 percent bentonite and prepared at 14, 16 and 18 percent initial moisture content were tested in this investigation. Results presented show the swelling characteristics of bottom ash-bentonite mixtures with curing age up to 60 days.

  3. Levels and patterns of polycyclic aromatic hydrocarbons in coal-fired power plant bottom ash and fly ash from Huainan, China.

    Science.gov (United States)

    Ruwei, Wang; Jiamei, Zhang; Jingjing, Liu; Liu, Guijian

    2013-08-01

    Fly ash and bottom ash samples were collected from a coal-fired power plant located in Anhui province, China. Mineral phases and morphologies of the samples were determined by X-ray diffraction and scanning electron microscopy, respectively. Sixteen polycyclic aromatic hydrocarbon (PAH; 16 compounds specified in United States Environmental Protection Agency Method 610) properties in ash samples were investigated. In fly ashes, ∑16PAH (total amount of 16 PAHs) and ∑CPAH (total amount of 8 carcinogenic PAHs) levels varied from 0.93 to 2.08 μg/g and from 0.26 to 0.87 μg/g, respectively. In bottom ashes, ∑16PAH and ∑CPAH levels varied from 2.83 to 5.32 and 1.76 to 3.76 μg/g, respectively. Fly ashes were dominated by medium molecular-weight PAHs and low molecular-weight PAHs, whereas bottom ashes were abundant in 5- and 6-ring PAH species. The CPAHs levels of some ashes, especially bottom ashes, are greater than the limits regulated by several countries, indicating that this type of coal combustion product requires special treatment before landfill. PAH levels and patterns in fly ash were evidently affected by particle size, and total organic content had a closer correlation with PAH content than particle size in bottom and fly ash, which may be due to unburned carbon existing in bottom ash.

  4. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

    Directory of Open Access Journals (Sweden)

    M. Adama

    2016-01-01

    Full Text Available Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (Igeo and pollution load indices (PLI were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69, Pb (143.80, Cr (99.30, and Cd (7.54 in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

  5. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site.

    Science.gov (United States)

    Adama, M; Esena, R; Fosu-Mensah, B; Yirenya-Tawiah, D

    2016-01-01

    Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

  6. X-Ray Diffraction Analysis of Bottom Ash Waste after Plasma Treatment

    Science.gov (United States)

    Volokitin, G.; Abzaev, Yu; Skripnikova, N.; Volokitin, O.; Shekhovtsov, V.

    2017-04-01

    The paper deals with the plasma-chemical synthesis of melts produced from the bottom ash waste for the production of new construction materials with enhanced performance characteristics. Phase composition of the plasma-treated bottom ash waste is detected by the X-ray diffraction analysis. The bottom ash waste is a mixture of SiO2 minerals. The structure and phase composition of this mixture are investigated after the plasma treatment. The obtained results are compared with the original state of the mixture. The identification and the qualitative content of ash waste as a multi-phase system are complicated by the overlapped reflections and a possible existence of the intermediate amorphous phase.

  7. Sieving of municipal solid waste incineration (MSWI) bottom ash; Siktning av askor fraan avfallsfoerbraenning

    Energy Technology Data Exchange (ETDEWEB)

    Todorovic, Jelena

    2010-07-01

    Waste-to-Energy is steadily increasing in Sweden and more than 46 % of municipal solid waste (MSW) is being incinerated. Solid residues from MSW incineration (MSWI) mainly constitute of bottom ash and air pollution control (APC) residues. Bottom ashes from MSWI amounted to 0.7 millions of tons and APC residues to 0.2 millions of tons in 2008. Bottom ashes from MSWI contain pollutants like metals (e.g. Pb, Zn, Cu), metalloids (e.g. As, Se), elements forming oxyanions (e.g. Sb, Cr, Mo) and easily soluble salts like chlorides and sulphates. These constituents can leach out polluting the environment if ash comes in contact with water. Treatment methods for decreasing the amount of pollutants in ashes or their mobility are therefore needed. Sieving was investigated as a separate or a complementary treatment method for MSWI ashes. Hypothesis was that the large share of pollutant concentrations could be removed from the ashes through separation of the finest fractions. The rest is less harmful to the environment, more acceptable as secondary construction material or less costly to landfill. Investigation included three MSWI ashes, namely bottom ash from Boraas Energy och Miljoe's plant with fluid bad, boiler ash from the same plant and bottom ash from Renova's stocker grate type plant. Ashes were sieved in 2-4 size fractions. Total content of pollutants and their leachability (batch leaching test, L/S=10 l/kg) was assessed for each of the fractions. Leaching results were compared to limit values stipulated by Swedish Environmental Protection Agency for acceptance of waste at landfills as wells as to recommendations for reuse of waste as a construction material. Results from bottom ash from the stocker grate type incinerator and from the boiler ash confirm the hypothesis that pollutants leach out in higher concentrations from the finer fractions. A large amount of pollutant could be removed from the ashes through sieving, but the goal to produce a fraction that

  8. Review: Application of coal bottom ash as aggregate replacement in highway embankment, acoustic absorbing wall and asphalt mixtures

    Science.gov (United States)

    Afiza Mohammed, Syakirah; Rehan Karim, Mohamed

    2017-06-01

    Worldwide annual production of coal bottom ash waste was increased in the last decade and is being dumped on landfill over the years. Its improper disposal has become an environmental concern and resulted in a waste of recoverable resources. There is a pressing and on-going need to develop new recycling methods for coal bottom ash. The utilization of coal bottom ash in highway engineering is one of the options to reduce the environmental problems related to the disposal of bottom ash. The present review describe the physical and chemical properties of coal bottom ash waste and its current application as highway embankment material, as acoustic absorbing material and as aggregate replacement in asphalt mixtures. The purpose of this review is to stimulate and promote the effective recycling of coal bottom ash in highway engineering industry.

  9. Reducing Heavy Metal Element from Coal Bottom Ash by Using Citric Acid Leaching Treatment

    Directory of Open Access Journals (Sweden)

    Yahya Ahmad Asyari

    2017-01-01

    Full Text Available Coal ash is the residue that is produced during coal combustion for instance fly ash, bottom ash or boiler slag which was primarily produced from the combustion of coal. With growth in coal burning power station, huge amount of coal bottom ash (CBA considered as hazardous material which are normally disposed in an on-site disposal system without any commercialization purpose. Previous researchers have studied the extraction of silica from agricultural wastes such as palm ash and rice husk ash (RHA and CBA by using leaching treatment method. In this study, the weaker acid, citric acid solution was used to replace the strong acid in leaching treatment process. Result showed that the heavy metal content such as Copper (Cu, Zinc (Zn and Lead (Pb can be decrease. Meanwhile the silica can be extracted up to 44% from coal bottom ash using citric acid leaching treatment under the optimum reaction time of 60 minutes with solution temperature of 60°C and concentration of citric acid more than 2%.

  10. Aluminium recovery from waste incineration bottom ash, and its oxidation level.

    Science.gov (United States)

    Biganzoli, Laura; Grosso, Mario

    2013-09-01

    The recovery of aluminium (Al) scraps from waste incineration bottom ash is becoming a common practice in waste management. However, during the incineration process, Al in the waste undergoes oxidation processes that reduce its recycling potential. This article investigates the behaviour of Al scraps in the furnace of two selected grate-fired waste-to-energy plants and the amount recoverable from the bottom ash. About 21-23% of the Al fed to the furnace with the residual waste was recovered and potentially recycled from the bottom ash. Out of this amount, 76-87% was found in the bottom ash fraction above 5 mm and thus can be recovered with standard eddy current separation technology. These values depend on the characteristics and the mechanical strength of the Al items in the residual waste. Considering Al packaging materials, about 81% of the Al in cans can be recovered from the bottom ash as an ingot, but this amount decreases to 51% for trays, 27% for a mix of aluminium and poly-laminated foils and 47% for paper-laminated foils. This shows that the recovery of Al from the incineration residues increases proportionally to the thickness of the packaging.

  11. Retention and leaching of nitrite by municipal solid waste incinerator bottom ash under the landfill circumstance.

    Science.gov (United States)

    Yao, Jun; Kong, Qingna; Zhu, Huayue; Long, Yuyang; Shen, Dongsheng

    2015-01-01

    The retention and leaching of nitrite by municipal solid waste incinerator (MSWI) bottom ash could affect its migration in the landfill. In this study, the effect of the dosage of MSWI bottom ash as well as the variation of the landfill environmental parameters including pH, anions and organic matter on the nitrite retention and leaching behavior was investigated by batch experiments. The highest removal percentage (73.0%) of nitrite was observed when the dosage of MSWI bottom ash was 10 g L(-1) in 2 mg L(-1) nitrite solution. Further increase of the dosage would retard the retention, as the nitrite leaching from MSWI bottom ash was enhanced. The optimum retention of nitrite was observed when the pH was 5.0, while the leaching of nitrite showed a consistent reduction with the increase of pH. Besides, the presence of Cl(-), SO4(2)(-) and acetic acid could enhance the leaching of nitrite and mitigate the retention process. However, the retention of nitrite was enhanced by PO4(3)(-), which was probably due to the formation of the apatite, an active material for the adsorption of the nitrite. These results suggested that MSWI bottom ash could affect the migration of nitrite in the landfill, which was related to the variation of the landfill circumstance. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Effects of substrate induced respiration on the stability of bottom ash in landfill cover environment.

    Science.gov (United States)

    Ilyas, A; Lovat, E; Persson, K M

    2014-12-01

    The municipal solid waste incineration bottom ash is being increasingly used to construct landfill covers in Sweden. In post-closure, owing to increased cover infiltration, the percolating water can add external organic matter to bottom ash. The addition and subsequent degradation of this external organic matter can affect metal mobility through complexation and change in redox conditions. However, the impacts of such external organic matter addition on bottom ash stability have not been fully evaluated yet. Therefore, the objective of this study was to evaluate the impact of external organic matter on bottom ash respiration and metal leaching. The samples of weathered bottom ash were mixed with oven dried and digested wastewater sludge (1%-5% by weight). The aerobic respiration activity (AT4), as well as the leaching of metals, was tested with the help of respiration and batch leaching tests. The respiration and heavy metal leaching increased linearly with the external organic matter addition. Based on the results, it was concluded that the external organic matter addition would negatively affect the quality of landfill cover drainage. © The Author(s) 2014.

  13. Utilization of power plant bottom-ash particles as stabilizer in aluminum foams

    Energy Technology Data Exchange (ETDEWEB)

    Asavavisithchai, Seksak; Prapajaraswong, Attanadol [Chulalongkorn Univ., Bangkok (Thailand). Dept. of Metallurgical Engineering

    2013-07-01

    Aluminum foams, produced via powder metallurgical (PM) process, normally require the addition of ceramic particles in compaction stage, in order to increase both foamability of precursors and mechanical properties of the final foam products. Bottom ash particles are a by-product waste obtained from thermoelectric power plants which are commonly found to be used in landfill facilities. The major chemical constituent, approximately between 30 wt.-% and 60 wt.-%, of bottom ash particles is SiO{sub 2}, depending on chemical composition in coal, sintering condition and environment, and other process parameters. In this study, we explore the feasibility of utilizing bottom ash particles of thermoelectric power plant wastes as stabilizer in aluminum foams. A small amount of two-size bottom ash particles (mean size of 78 {mu}m and 186 {mu}m), between 1 wt.-% and 5 wt.-%, have been added to aluminum foams. Foam expansion, macro- and microstructures as well as mechanical properties, such as compressive strength and microhardness, were investigated. The results from the present study suggest that bottom ash particles can be used as a stabilizing material which can improve both cellular structure and mechanical properties of aluminum foams. (orig.)

  14. Behavior study of trace elements in pulverized lignite, bottom ash, and fly ash of Amyntaio power station, Greece.

    Science.gov (United States)

    Megalovasilis, Pavlos; Papastergios, Georgios; Filippidis, Anestis

    2013-07-01

    The Kozani-Ptolemais-Amyntaio basin constitutes the principal coal field of Greece. Approximately 50% of the total power production of Greece is generated by five power stations operating in the area. Lignite samples, together with the corresponding fly ash and bottom ash were collected, over a period of 3 months, from the power plant of Amyntaio and analyzed for their content in 16 trace elements. The results indicate that Y, Nb, U, Rb, Zr, Ni, Pb, Ba, Zn, Sr, Cu, and Th demonstrate an organic affinity during the combustion of lignite, while V has an inorganic affinity. Three elements (Co, Cr, and Sc) show an intermediate affinity.

  15. The Laconia, New Hampshire bottom ash paving project: Volume 3, Physical Performance Testing Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Bottom ash is the principal waste stream from the combustion of municipal solid waste (MSW). It is comprised of grate ash (97%), the slag material discharged at the end of the grate system, and grate sifting (3%), the material that melts or falls through the grate structure. This project was conducted to demonstrate the feasibility of using municipal solid waste grate ash as an aggregate substitute in the construction of a pavement binder course for a portion of Rt. 3 in Laconia, New Hampshire. The research was conducted over a two year period during 1993 and 1994. This study is the culmination of an earlier two year characterization study between 1990 and 1992 that documented the physical and environmental characteristics of the bottom ash as it was produced at the Concord, N.H. waste-to-energy (@) facility and used in an asphaltic binder course. Together, these two studies provide a complete evaluation of the potential for using grate ash or bottom ash in asphalt binder course or as recycled asphalt pavement (RAP) in base courses in pavements.

  16. Characterisation of MSWI bottom ash for potential use as subbase in Greenlandic road construction

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Jørgensen, Anders Stuhr; Ingeman-Nielsen, Thomas

    2012-01-01

    The waste management situation in Greenland needs to be improved. Most waste in towns is incinerated with only limited separation prior to incineration and the bottom ash residue is disposed of at uncontrolled disposal sites. The bottom ash could be a valuable resource within the expansion...... was acceptable for reuse after some small adjustments in the grain size distribution to prevent frost sensitivity. Results obtained from heavy metal content and heavy metal leaching complied with the Danish guideline values for reuse of waste materials in construction. Leaching of Cu and Cr was high from small...

  17. Leachate formation and characteristics from gasification and grate incineration bottom ash under landfill conditions.

    Science.gov (United States)

    Sivula, Leena; Sormunen, Kai; Rintala, Jukka

    2012-04-01

    Characteristics and formation of leachates from waste gasification and grate firing bottom ash were studied using continuous field measurements from 112 m(3) lysimeters embedded into landfill body for three years. In addition, the total element concentrations of the fresh ash were analysed and laboratory batch tests were performed to study leachate composition. The three-year continuous flow measurement showed that about one fifth of the leachates were formed, when the flow rate was >200 l/d, covering 13) major part of the study. In the grate ash leachate pH was lower (landfill conditions. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Effect of mixes made of coal bottom ash and fly ash on the mechanical strength and porosity of Portland cement

    Directory of Open Access Journals (Sweden)

    Argiz, C.

    2013-03-01

    Full Text Available New additions to the cement are needed to achieve a more sustainable and durable construction material. Within this context, bottom ashes can be used as a main constituent of Portland cements when it is mixed in an optimized proportion with fly ashes. The mechanical characteristics of standarized mortars made of mixes of pulverized coal combustion bottom and fly ashes are studied. The mortars were made of ordinary Portland cement (CEM I 42.5 N and mixes of bottom ashes with fly ashes in similar proportions to those of CEM II/A-V, CEM II/B-V and CEM IV/A (V. Summing up, it can be said that the utilization of bottom ashes mixed with fly ashes in replacement levels from 0% to 100% do not affect significantively on the mechanical caracteristics of the mortars considered in the present study which had an addition maximum content of 35%.

    La utilización de nuevas adiciones en el cemento es necesaria con el fin de obtener un material más sostenible y durable. En este sentido, las cenizas de fondo o cenicero de las centrales termoeléctricas de carbón se podrían reciclar siendo empleadas como un componente principal de los cementos Portland. Se han estudiado las propiedades mecánicas de unos morteros normalizados elaborados con mezclas de cenizas volantes con cenizas de fondo fabricados con unos porcentajes similares a los correspondientes de los CEM II/A-V, CEM II/B-V y CEM IV/A (V. En conclusión, la utilización de mezclas de cenizas de fondo o cenicero con cenizas volantes sustituyendo a éstas últimas entre el 0% y el 100%, no influye significativamente en el comportamiento mecánico de los morteros estudiados en los que el contenido máximo de adición ha sido del 35%, si bien afecta a determinados aspectos microestructurales, como la cantidad y distribución de poros capilares.

  19. Quality criteria for bottom ashes for civil construction. Part II Technical characteristics of bottom ashes; Kvalitetskriterier foer bottenaskor till vaegoch anlaeggningsbyggnad. Etapp II Bottenaskors tekniska egenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Bahr, Bo von; Loorents, Karl-Johan; Ekvall, Annika; Arvidsson, Haakan [SP Swedish National Testing and Research Inst., Boraas (Sweden)

    2006-01-15

    This report is the presentation of the second of two stages. This stage deals mainly with the testing of three different types of ashes and the evaluation and suitability of the chosen test methods. The project only relates to the technical aspects of ashes. The report is written in such a way that both ash owners (e.g. Energy companies) and those who build roads and constructions will find it meaningful. All test methods that are used for traditional materials (gravel and crushed rock) is not fitting for ashes. New test methods for some properties that will be tested must therefore be presented, tested practically and evaluated. The project encompasses both road and construction building but has a focus on road construction since there the highest and comprising demands are defined. Three bottom ashes of different types have been studied regarding some tenfold mechanical/physical parameters, essential for the functionality of the ash as a construction material. An important conclusion is that ash is from a functionality and characterisation point of view, an undefined concept that encloses materials with widely different properties. Despite that only three ashes have been looked into the range of results are varying large for some properties. This is especially true for the loose bulk density, water absorption and grain size distribution. It is also clear that some of the standard test methods for aggregates need to be exchanged by other methods, which are more adapted to alternative materials. One such example is water absorption, a property that further influences frost resistance, frost heave and such. All the proposed test methods that been used in the project is considered fitting for its purpose. The test methods can be divided into two categories the ones that yield easy assessable results and those that yield results hard to appraise. To the first group belong grain size distribution, loose bulk density, thermal conductivity, permeability and frost heave

  20. Carbon speciation in municipal solid waste incinerator (MSWI) bottom ash in relation to facilitated metal leaching

    NARCIS (Netherlands)

    Zomeren, van A.; Comans, R.N.J.

    2009-01-01

    The release of inorganic and organic contaminants from municipal solid waste incinerator (MSWI) bottom ash is controlled to a large extent by the release of dissolved organic carbon (DOC), and in particular by the reactive humic (HA) and fulvic acids (FA) subfractions of DOC. The properties of organ

  1. Effect of accelerated aging of MSWI bottom ash on the leaching mechanisms of copper and molybdenum

    NARCIS (Netherlands)

    Dijkstra, J.J.; Zomeren, van A.; Meeussen, J.C.L.; Comans, R.N.J.

    2006-01-01

    The effect of accelerated aging of Municipal Solid Waste Incinerator (MSWI) bottom ash on the leaching of Cu and Mo was studied using a "multisurface" modeling approach, based on surface complexation to iron/aluminum (hydr) oxides, mineral dissolution/precipitation, and metal complexation by humic s

  2. Process identification and model development of contaminant transport in MSWI bottom ash

    NARCIS (Netherlands)

    Dijkstra, J.J.; Sloot, van der H.A.; Comans, R.N.J.

    2002-01-01

    In this work we investigate to what extent we are able to predict experimental data on column leaching of heavy metals from municipal solid waste incinerator (MSWI) bottom ash, using the current knowledge on processes controlling aqueous heavy metal concentrations in combination with a multicomponen

  3. Microwave-assisted synthesis of geopolymers from fluidised bed gasifier bottom ash

    CSIR Research Space (South Africa)

    Oboirien, BO

    2013-09-01

    Full Text Available -1 International Conference of Coal Science and Technology, State College, Pennysylvania, USA, 29 September- 3 October 2013 Microwave-assisted synthesis of geopolymers from fluidised bed gasifier bottom ash B.O. Oboirien1, B.C. North1 and E. R. Sadiku2...

  4. Leaching from MSWI bottom ash: Evaluation of non-equilibrium in column percolation experiments

    DEFF Research Database (Denmark)

    Hyks, Jiri; Astrup, Thomas; Christensen, Thomas Højlund

    2009-01-01

    Impacts of non-equilibrium on results of percolation experiments on municipal solid waste incineration (MSWI) bottom ash were investigated. Three parallel column experiments were performed: two columns with undisturbed percolation and one column with two sets of 1-month-long flow interruptions...

  5. The Properties of Special Concrete Using Washed Bottom Ash (WBA as Partial Sand Replacement

    Directory of Open Access Journals (Sweden)

    Mohd Syahrul Hisyam Mohd Sani

    2011-07-01

    Full Text Available This paper presents the use of Washed Bottom Ash (WBA as fine aggregate in special concrete. The WBA is a waste material that is taken from electric power plant and the source material is called as bottom ash. To substitute the amount of carbon usage in concrete the bottom ash was utilized and fully submerged in water for 3 days to produce as WBA with low carbon composition. The aim of the study is to investigate the feasibility and potential use of washed bottom ash in concreting and concrete applications. The results of the physical and chemical properties of WBA were discussed. Different concrete mixes with constant water to cement ratio of 0.55 were prepared with WBA in different proportions as well as one control mixed proportion. The mechanical properties of special concrete with 30% WBA replacement by weight of natural sand is found to be an optimum usage in concrete in order to get a favourable strength and good strength development pattern over the increment ages.

  6. Adsorption and desorption characteristics of crystal violet in bottom ash column

    Directory of Open Access Journals (Sweden)

    Puthiya Veetil Nidheesh

    2012-06-01

    Full Text Available This study described adsorption of Crystal Violet (CV by bottom ash in fixed-bed column mode. Equilibrium of adsorption was studied in batch mode for finding adsorption capacity of bottom ash. In fixed bed column adsorption, the effects of bed height, feed flow rate, and initial concentration were studied by assessing breakthrough curve. The slope of the breakthrough curve decreased with increasing bed height. The breakthrough time and exhaustion time were decreased with increasing influent CV concentration and flow rates. The effect of bed depth, flow rate and CV concentration on the adsorption column design parameters were analyzed. Bed depth service time (BDST model was applied for analysis of crystal violet adsorption in the column. The adsorption capacity of bottom ash was calculated at 10% breakthrough point for different flow rates and concentrations. Desorption studies reveals that recovery of CV from bottom ash was effective by using CH3COOH than H2SO4, NaOH, HCl and NaCl solutions.

  7. ADSORPTION AND DESORPTION CHARACTERISTICS OF CRYSTAL VIOLET IN BOTTOM ASH COLUMN

    Directory of Open Access Journals (Sweden)

    Puthiya Veetil Nidheesh

    2012-01-01

    Full Text Available This study described adsorption of Crystal Violet (CV by bottom ash in fixed-bed column mode. Equilibrium of adsorption was studied in batch mode for finding adsorption capacity of bottom ash. In fixed bed column adsorption, the effects of bed height, feed flow rate, and initial concentration were studied by assessing breakthrough curve. The slope of the breakthrough curve decreased with increasing bed height. The breakthrough time and exhaustion time were decreased with increasing influent CV concentration and flow rates. The effect of bed depth, flow rate and CV concentration on the adsorption column design parameters were analyzed. Bed depth service time (BDST model was applied for analysis of crystal violet adsorption in the column. The adsorption capacity of bottom ash was calculated at 10% breakthrough point for different flow rates and concentrations. Desorption studies reveals that recovery of CV from bottom ash was effective by using CH3COOH than H2SO4, NaOH, HCl and NaCl solutions.

  8. Major and trace elements in coal bottom ash at different oxy coal combustion conditions

    CSIR Research Space (South Africa)

    Oboirien, BO

    2014-09-01

    Full Text Available This paper presents a detailed study on the effect of temperature on the concentration of 27 major and trace elements in bottom ash generated from oxy fuel-combustion. The major elements are Na, Mg, Al, K, Ca and Fe and the minor and trace elements...

  9. 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 H2S elimination from landfill biogas was evaluated. Emphasis was given to the influence of water content in biogas on H2S 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 CH4, CO2, O2, H2S and H2O in raw and treated biogas. The H2S removal efficiency of bottom ash was evaluated for different inlet biogas humidities: from 4 to 24gwater/m(3). The biogas water content was found to greatly affect bottom ash efficiency regarding H2S removal. With humid inlet biogas the H2S removal was almost 3 times higher than with a dry inlet biogas. Best removal capacity obtained was 56gH2S/kgdryBA. A humid inlet biogas allows to conserve the bottom ash moisture content for a maximum H2S retention. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Leaching kinetics of bottom ash waste as a source of calcium ions.

    Science.gov (United States)

    Koech, Lawrence; Everson, Ray; Neomagus, Hein; Rutto, Hilary

    2015-02-01

    Bottom ash is a waste material from coal-fired power plants, and it is known to contain elements that are potentially toxic at high concentration levels when disposed in landfills. This study investigates the use of bottom ash as a partial substitute sorbent for wet flue gas desulfurization (FGD) processes by focusing on its leaching kinetics in adipic acid. This was studied basing on the shrinking core model that was applied to the experimental data obtained by the authors presented at the International Conference on Industrial, Manufacturing, Automation and Mechanical Engineering, Johannesburg, South Africa, November 27-28, 2013) on dissolution of bottom ash. The leaching rate constant was obtained from different reaction variables, namely, temperature, pH, acid concentration, and solid-to-liquid ratio, that could affect the leaching process. The solid sample of bottom ash was characterized at different leaching periods using X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that solid-to-liquid ratio had a significant effect on the leaching rate constant when compared with other variables. The leaching kinetics showed that diffusion through the product layer was the rate-controlling step during leaching, and the activation energy for the process was found to be 18.92 kJ/mol.

  11. Mechanical and leaching properties of blended systems containing OPC and incinerator bottom ash

    Energy Technology Data Exchange (ETDEWEB)

    Onori, R.; Polettini, A.; Pomi, R. [Rome Univ. (Italy). Dept. of Hydraulics, Transportation and Roads

    2010-07-01

    Chemical and mechanical activation processes were applied to improve the reactivity of incinerator bottom ash in Portland cement mixtures. Sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium chloride (CaCI{sub 2}) and calcium sulfate (CaSO{sub 4}) activators were used in experiments conducted to determine bottom ash content, activator type, and activator dosages for varying amounts of cement and bottom ash. The study evaluated the evolution of mechanical strength and the leaching behaviour of both major and trace elements from the activated bottom ash and Portland cement mixtures. Results of the study showed that the use of CaCI{sub 2} improved the hydration process in the mixtures. A positive effect on mechanical strength was noted when CaSO{sub 4} was used as an activator. Trace metals were efficiently immobilized within the hardened materials for all the tested activators. Geochemical modelling was used to determine the main hydration phases of the leaching solutions. No mineral phases were identified as potential solubility-controlling solids. Results of the study indicated the presence of heavy metals as complex phase assemblages in the hardened materials. 40 refs., 2 tabs., 8 figs.

  12. Chemical extraction of organic carbon to reduce the leaching potential risk from MSWI bottom ash.

    Science.gov (United States)

    Guimaraes, A L; Okuda, T; Nishijima, W; Okada, M

    2005-10-17

    The performance of extraction solvents, including organic and inorganic solvents, for organic carbon extraction from municipal solid waste incinerator (MSWI) bottom ash was evaluated. The total carbon (TC) extracted was used to ascertain the efficiency of extraction solvents and the reduction of dissolved organic carbon (DOC) leaching potential was used to evaluate the capacity of solvents to minimize environmental impacts of MSWI bottom ash over short- and long-term considerations in landfill sites. Extract final pH value was a prominent parameter affecting TC extraction. The higher efficiency was obtained at the lower extract final pH and acid or neutral condition was necessary to achieve approximately 30% of TC extraction from bottom ash. On the basis of the results of TC extraction, the efficiency of organic carbon reduction was evaluated using organic carbon leaching potential. Hydrochloric acid was the best solvent to extract organic carbon in controlled pH conditions. Hydrochloric acid reduced the organic carbon leaching potential of MSWI bottom ash by about 68% at neutral leaching pH.

  13. Numerical modelling of the generation and transport of heat in a bottom ash monofill.

    Science.gov (United States)

    Klein, R; Nestle, N; Niessner, R; Baumann, T

    2003-06-27

    Municipal solid waste is incinerated to reduce its volume, toxicity and reactivity. Several studies have shown that the resulting bottom ash has a high exothermic capacity. Temperature measurements in municipal solid waste incineration (MSWI) bottom ash landfills have found temperatures up to 90 degrees C. Such high temperatures may affect the stability of the landfill's flexible polymer membrane liner (FML) and may also lead to an accelerated desiccation of the clay barrier. The purpose of this study was to gain detailed knowledge of temperature development under several disposal conditions in relation to the rate of ash disposal, the variation of layer thickness, and the environmental conditions in a modern landfill. Based on this knowledge, a simulation was developed to predict temperature development. Temperature development was simulated using several storage periods prior to the deposition and several modes of emplacement. Both the storage time and the mode of emplacement have a significant influence on the temperature development at the sensitive base of the landfill. Without a preliminary storage of the fresh quenched bottom ash, high temperatures at the bottom of a landfill cannot be avoided.

  14. Characteristics of residual organics in municipal solid waste incinerator bottom ash.

    Science.gov (United States)

    Lin, Yen-Ching; Yen, Jui-Hung; Lateef, Shaik Khaja; Hong, Pui-Kwan Andy; Lin, Cheng-Fang

    2010-10-15

    Although heavy metals in bottom ash have been a primary issue in resource recovery of municipal solid waste incinerator residues in past decades, less studied are potentially toxic and odorous organic fractions that exist as they have not been completely oxidized during the mass burn process. Using supercritical fluid extraction (SFE) and soxtec extraction (SE) techniques, this study investigated the characteristics of un-oxidized organic residues contained in bottom ash from three municipal solid waste incinerators in Taiwan during 2008-2009. All together 99 organics were identified in bottom ash samples using gas chromatography-mass spectrometry (GC-MS). Among the identified organics, aromatic compounds were most frequently detected. No polycyclic aromatic hydrocarbons were extracted by SFE or SE. Several phthalates (e.g., phthalic acid isobutyl tridec-2-yn-1-yl ester, dibutyl phthalate and 2-butoxyethyl butyl benzene-1,2-dicarboxylate), organic phosphates (e.g., octicizer and phosphoric acid isodecyl diphenyl ester), and aromatics and amines including pyridine, quinoline derivatives, chloro- and cyano-organics were successfully extracted. Aromatic amines (e.g., 1-nitro-9,10-dioxo-9,10-dihydro-anthracene-2-carboxylic acid diethylamide and 3-bromo-N-(4-bromo-2-chlorophenyl)-propanamide) and aromatic compounds (other than amines) (e.g., 7-chloro-4-methoxy-3-methylquinoline and 2,3-dihydro-N-hydroxy-4-methoxy-3,3-dimethyl indole-2-one) are probably the major odorous compounds in bottom ash. This work identifies organic pollutants in incinerated bottom ash that have received far less attention than their heavy metals counterpart.

  15. Moessbauer effect study of fly and bottom ashes from an electric generating plant

    Energy Technology Data Exchange (ETDEWEB)

    Vandenberghe, R. E., E-mail: Robert.Vandenberghe@UGent.be; Resende, V. G. de; De Grave, E. [Ghent University, Department of Subatomic and Radiation Physics (Belgium)

    2009-06-15

    Samples of a fly ash and a bottom ash, each before and after ignition, have been investigated by X-ray diffraction and Moessbauer spectroscopy in order to explain the observed negative loss of ignition (LOI). It is shown that the ashes after ignition contain more maghemite resulting from newly formed magnetite. Moreover, the fly ash which contained already magnetite exhibited an increase of hematite after ignition. Both oxidation processes can be responsible for a weight gain which compensates the loss due to the burning of the remaining carbon. The magnetite and the alpha-iron formed after ignition is originated by an unidentified compound represented by a Fe{sup 2+} doublet in the Moessbauer spectrum.

  16. Foamed bitumen stabilization of MSWI bottom ash; Skumbitumenstabilisering av bottenaska fraan avfallsfoerbraenning

    Energy Technology Data Exchange (ETDEWEB)

    Bendz, David [Swedish Geotechnical Inst., Linkoeping (Sweden); Jacobsson, Torbjoern [Swedish National Road and Transport Research Inst., Linkoeping (Sweden); Svensson, Mikael; Flyhammar, Peter [Lund Inst. of Technology (Sweden). Dept. of Water Resources Engineering

    2006-04-15

    Foamed bitumen is a mixture of bitumen, water and air. Bitumen that is heated to 175 deg C expands about 10-30 times compared to its original volume when injecting small amounts of water and air under high pressure. By exposing a granulate material to foamed bitumen the particles will be covered with a bitumen film. This will give the particles hydrophobic properties, as well as a smaller specific surface. At the same time the mechanical properties of the material are expected to improve due to the cohesive properties of the bitumen covered particles. The treatment can be made both offsite and in situ. The objective of this project was to investigate the possibility to treat municipal solid waste bottom ash with foamed bitumen to achieve improved leaching and mechanical properties. The following leaching tests have been performed on the original bottom ash and two foamed bitumen treated ashes with 2 and 4.5 % bitumen, respectively: one-stage batch test (EN 12457-4), pH-static test (prEN 14997), column test (prEN 14405) and monolithic leaching test (NEN 7345). In addition, the specific surface and intra-particle porosity were determined by BET N2 adsorption experiments on selected fractions of bottom ash. The results showed that the specific surface decreased with more than 50 % and manifested itself in a lower buffer capacity at both low and high pH. For most elements no significant difference in leaching behavior where found when comparing the results from the leaching tests for the three materials at their own pH. This is thought to be due to that sufficient specific area available for leaching exists to reach equilibrium despite the foam bitumen treatment. The results from the one-stage batch test show a minor reduction in leaching for Cl{sup -}, S, SO{sub 4}{sup -2}, NO{sub 3}{sup -}, Sb, and Ca for the foamed bitumen treated ashes. The results from the column test of the foamed bitumen stabilized ashes showed an increased leaching of some elements, especially

  17. Effect of ferrous metal presence on lead leaching in municipal waste incineration bottom ashes.

    Science.gov (United States)

    Oehmig, Wesley N; Roessler, Justin G; Zhang, Jianye; Townsend, Timothy G

    2015-01-01

    The recovery of ferrous and non-ferrous metals from waste to energy (WTE) ash continues to advance as the sale of removed metals improves the economics of waste combustion. Published literature suggests that Fe and Fe oxides play a role in suppressing Pb leaching in the Toxicity Characteristic Leaching Procedure (TCLP); further removal of ferrous metals from WTE ashes may facilitate higher Pb leaching under the TCLP. Eight WTE bottom ash size-fractions, from three facilities, were evaluated to assess the effect of metallic Fe addition and ferrous metal removal on TCLP leaching. Metallic Fe addition was demonstrated to reduce Pb leaching; the removal of ferrous metals by magnet resulted in a decrease in total available Pb (mg/kg) in most ash samples, yet Pb leachability increased in 5 of 6 ash samples. The research points to two chemical mechanisms to explain these results: redox interactions between Pb and Fe and the sorption of soluble Pb onto Fe oxide surfaces, as well as the effect of the leachate pH before and after metals recovery. The findings presented here indicate that generators, processors, and regulators of ash should be aware of the impact ferrous metal removal may have on Pb leaching, as a substantial increase in leaching may have significant implications regarding the management of WTE ashes. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Performance appraisal of industrial waste incineration bottom ash as controlled low-strength material.

    Science.gov (United States)

    Razak, Hashim Abdul; Naganathan, Sivakumar; Hamid, Siti Nadzriah Abdul

    2009-12-30

    Controlled low-strength material (CLSM) is slurry made by mixing sand, cement, ash, and water. It is primarily used as a replacement for soil and structural fillings. This paper presents the findings of a preliminary investigation carried out on the performance of industrial waste incineration bottom ash as CLSM. CLSM mixes were designed using industrial waste incineration bottom ash, and cement. Tests for density, setting time, bleed, and compressive strength on cubes under various curing conditions, corrosivity, and leaching of heavy metals and salts were carried out on the CLSM mixtures, and the results discussed. Compressive strength for the designed CLSM mixtures ranged from 0.1 to 1.7 MPa. It is shown that the variations in curing conditions have less influence on the compressive strength of CLSM at high values of water to cement ratio (w/c), but low values of w/c influences the strength of CLSM. The CLSM produced does not exhibit corrosive characters as evidenced by pH. Leaching of heavy metals and salts is higher in bleed than in leachate collected from hardened CLSM. Cement reduces the leaching of Boron in bleed. It is concluded that there is good potential for the use of industrial waste incineration bottom ash in CLSM.

  19. Potential exposure levels and health effects of neighborhood exposure to a municipal incinerator bottom ash landfill.

    Science.gov (United States)

    Stern, A H; Munshi, A A; Goodman, A K

    1989-01-01

    An investigation was conducted to assess the potential exposure levels and pursuant public health implications of neighborhood exposure to a municipal incinerator bottom ash landfill. This site received ash from a single incinerator without pollution control devices from 1954-1973. Soil was sampled for 10 heavy metals, polychlorinated dibenzodioxins, polychlorinated dibenzofurans, 2,3,7,8-tetrachlorodioxin and furan congeners, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons. Soil concentrations for these substances were converted to estimates of exposure, health effects, and/or cancer risk by the application of a general exposure model and exposure/effect and exposure/risk models for specific substances. The results of soil analysis and modeling indicate that the level of lead detected on the site was considerably above the recommended levels of the Centers for Disease Control (CDC) and may lead to an elevated blood lead level in exposed children above that currently defining a case of lead poisoning. The potential for health effects resulting from exposure to other substances measured in the soil on this site is considered to be small, and no significant increased cancer risk is expected. Comparison of levels of various substances obtained at this site with levels obtained in fresh bottom ash in other studies suggests that these results may be applicable to exposures from other municipal incinerator bottom ash landfills.

  20. Preliminary Examination of the System Fly Ash-Bottom Ash-Flue Gas Desulphurization Gypsum-Portland Cement-Water for Road Construction

    Directory of Open Access Journals (Sweden)

    R. Tokalic

    2013-01-01

    Full Text Available This paper describes an investigation into the use of three power plant wastes: fly ash, flue gas desulphurization gypsum, and bottom ash for subbase layers in road construction. Two kinds of mixtures of these wastes with Portland cement and water were made: first with fly ash consisting of coarser particles (<1.651 mm and second with fly ash consisting of smaller particles (<0.42 mm. The mass ratio of fly ash-Portland cement-flue gas desulphurization gypsum-bottom ash was the same (3 : 1 : 1 : 5 in both mixtures. For both mixtures, the compressive strength, the mineralogical composition, and the leaching characteristics were determined at different times, 7 and 28 days, after preparation. The obtained results showed that both mixtures could find a potential use for subbase layers in road construction.

  1. Migration of nitrate, nitrite, and ammonia through the municipal solid waste incinerator bottom ash layer in the simulated landfill.

    Science.gov (United States)

    Yao, Jun; Chen, Luxi; Zhu, Huayue; Shen, Dongsheng; Qiu, Zhanhong

    2017-04-01

    Simulated landfill was operated for 508 days to investigate the effect of municipal solid waste incinerator (MSWI) bottom ash layer on the migration of nitrate, nitrite, and ammonia when it was used as the intermediate layer in the landfill. The result suggested that the MSWI bottom ash layer could capture the nitrate, nitrite, and ammonia from the leachate. The adsorption of the nitrate, nitrite, and ammonia on the MSWI bottom ash layer was saturated at the days 396, 34, and 97, respectively. Afterwards, the nitrogen species were desorbed from the MSWI bottom ash layer. Finally, the adsorption and desorption could reach the equilibrium. The amounts of adsorbed nitrate and nitrite on the MSWI bottom ash layer were 1685.09 and 7.48 mg, respectively, and the amount of the adsorbed and transformed ammonia was 13,773.19 mg, which was much higher than the desorbed. The water leaching test and synthetic precipitation leaching procedure (SPLP) results showed that the leachable nitrate, nitrite, and ammonia in the MSWI bottom ash were greatly increased after the landfill operation, suggesting that the adsorbed nitrogen could be finally leached out. Besides, the results also showed that MSWI bottom ash layer could affect the release of nitrate and ammonia at the initial stage of the landfill. However, it had little effect on the release of nitrite.

  2. Modelling of landfill gas adsorption with bottom ash for utilization of renewable energy

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Chen

    2011-10-06

    Energy crisis, environment pollution and climate change are the serious challenges to people worldwide. In the 21st century, human being is trend to research new technology of renewable energy, so as to slow down global warming and develop society in an environmentally sustainable method. Landfill gas, produced by biodegradable municipal solid waste in landfill, is a renewable energy source. In this work, landfill gas utilization for energy generation is introduced. Landfill gas is able to produce hydrogen by steam reforming reactions. There is a steam reformer equipment in the fuel cells system. A sewage plant of Cologne in Germany has run the Phosphoric Acid Fuel Cells power station with biogas for more than 50,000 hours successfully. Landfill gas thus may be used as fuel for electricity generation via fuel cells system. For the purpose of explaining the possibility of landfill gas utilization via fuel cells, the thermodynamics of landfill gas steam reforming are discussed by simulations. In practice, the methane-riched gas can be obtained by landfill gas purification and upgrading. This work investigate a new method for upgrading-landfill gas adsorption with bottom ash experimentally. Bottom ash is a by-product of municipal solid waste incineration, some of its physical and chemical properties are analysed in this work. The landfill gas adsorption experimental data show bottom ash can be used as a potential adsorbent for landfill gas adsorption to remove CO{sub 2}. In addition, the alkalinity of bottom ash eluate can be reduced in these adsorption processes. Therefore, the interactions between landfill gas and bottom ash can be explained by series reactions accordingly. Furthermore, a conceptual model involving landfill gas adsorption with bottom ash is developed. In this thesis, the parameters of landfill gas adsorption equilibrium equations can be obtained by fitting experimental data. On the other hand, these functions can be deduced with theoretical approach

  3. Batch and Column Operations for the Removal of Fluoride from Aqueous Solution Using Bottom Ash

    Directory of Open Access Journals (Sweden)

    S.T. Ramesh

    2012-06-01

    Full Text Available Millions of people rely on drinking water that contains excess fluoride. In fluoride endemic areas, especially small communities with staggered habitat, defluoridation of potable water supply is still a problem. In this study, adsorption potential of bottom ash was investigated for defluoridation of drinking water using batch and continuous fixed bed column studies. Batch sorptive defluoridation conducted under experimental conditions such as pH, temperature, particle size, agitation time and dosage. Adsorption isotherms have been modeled by Langmuir and Freundlich isotherms. The fluoride sorption capacity at breakthrough point for bottom ash was greatly influenced by bed depth. The results were then analyzed using the Bed Depth Service Time (BDST Model and various performance parameters like Adsorption Capacity, Critical Bed Depth, and Adsorption Rate Constant were evaluated. With the observed data Thomas model and Yoon Nelson Model fitted well and constants are found.DOI: http://dx.doi.org/10.5755/j01.erem.60.2.1396

  4. Corrosion and mechanical performance of reinforced mortar and concrete made with MSWI bottom ash

    Directory of Open Access Journals (Sweden)

    Rita Ávila

    2017-07-01

    Full Text Available Electrochemical monitoring was performed to evaluate the influence of municipal solid waste incineration residues (MSWI made concrete, on reinforcement corrosion, using four different steel reinforce-ments grades, traditional carbon steel B-500-SD and three stainless steels, the austenite AISI 304, duplex AISI 2304, and lean-duplex AISI 2001, embedded in mortars manufactured using bottom ash as aggregates from the incineration of municipal solid waste (MSW, in partial and total substitution of natural aggregate. In addition, it has been studied the mechanical behaviour of the mortar and concrete matrix in the presence of MSWI aggre-gates. The use of MSWI bottom ash as an aggregate, results in a notable improvement of the resistance charac-teristics of conventional mortar and concrete, made out only of natural aggregate. Moreover, electrochemical measures show that the steels remain in passive state throughout all the exposure period (3 years.

  5. Adsorption of Ammonia on Municipal Solid Waste Incinerator Bottom Ash Under the Landfill Circumstance

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jun; Kong, Qingna; Zhu, Huayue; Zhang, Zhen [Taizhou University, Linhai (China); Long, Yuyang; Shen, Dongsheng [Zhejiang Gongshang University, Hangzhou (China)

    2015-08-15

    The adsorption characteristics of ammonia on MSWI bottom ash were investigated. The effect of the variation of the landfill environmental parameters including pH, anions and organic matter on the adsorption process was discussed. Results showed that the adsorption could be well described by pseudo-second-order kinetics and Langmuir model, with a maximum adsorption capacity of 156.2 mg/g. The optimum adsorption of ammonia was observed when the pH was 6.0. High level of ion and organic matter could restrict the adsorption to a low level. The above results suggested that MSWI bottom ash could affect the migration of ammonia in the landfill, which is related to the variation of the landfill circumstance.

  6. A Review: The Effect of Grinded Coal Bottom Ash on Concrete

    Directory of Open Access Journals (Sweden)

    Basirun Nurul Fasihah

    2017-01-01

    Full Text Available This paper offers a review on the use of grinded coal bottom ash (CBA on the concrete properties as demonstrated by strength test and microstructure test. Amount of CBA from power plant station was disposed in landfill because of the particle shape had a rough particles. By finding an alternative way to gain its surface area by grinding and used as replacement material as cement replacement may give a good side feedback on the strength and morphology of concrete. Most of the prior works studied on the grinded fly ash and grinded rice husk ash. The study on the influence of grinded CBA on the properties of concrete still limited and need more attention Therefore, the review on the effect of grinded CBA on the strength and microstructure of concrete are discussed.

  7. The partitioning of calcium and sulfur between bottom ash and flyash in a commercial CFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Rozelle, P.L.; Pisupati, S.V.; Morrison, J.L.; Scaroni, A.W.

    1999-07-01

    As part of a program to examine the effect of sorbent properties on sulfation performance in the circulating fluidized bed (CFB) combustion process, a series of sorbents varying in chemical composition was tested under similar operating conditions in a 30 MW(e) CFB boiler. These sorbents ranged from 27.8 to 55.2 wt% CaO, and from 0.54 to 18.8 wt% MgO. The fuel used was a high ash content (68 wt%) coal refuse. Parameters of boiler operation were established from distributed control system data, used to screen test results, and data were eliminated from consideration where changes in boiler load or bed inventory levels were seen prior to sampling of bottom ash and flyash streams. This, and the development of a set of simultaneous equations for measuring individual ash stream flow rates, allowed the computation of calcium and sulfur material balances around the boiler for each sorbent test. The partitioning of calcium and sulfur to the bottom ash and flyash streams was examined. It was found that the majority of both calcium and sulfur fed to the boiler was removed with the flyash, regardless of the sorbent. It was further found that across the range of sorbent properties, the flow of sulfur as a solid with the flyash was relatively uniform (71 to 86 wt% of that fed to the boiler). Calcium to sulfur ratios in the bottom ash were uniformly higher than those found for the corresponding flyash streams, indicating that attrition may play a key role in overall sorbent performance. The calcium balance data also indicated that thermally induced fractures (TIFs) may affect attrition.

  8. The impact of thermal treatment and cooling methods on municipal solid waste incineration bottom ash with an emphasis on Cl.

    Science.gov (United States)

    Yang, Shuo; Saffarzadeh, Amirhomayoun; Shimaoka, Takayuki; Kawano, Takashi; Kakuta, Yoshitada

    2016-10-01

    Municipal solid waste incineration (MSWI) bottom-ash products possess qualifications to be utilized in cement production. However, the instant use of bottom ash is inhibited by a number of factors, among which the chlorine (Cl) content is always strictly restricted. In this paper, the unquenched MSWI bottom ash was used as the experimental substance, and the influences of thermal treatment and cooling methods on the content and existence of Cl in the ash residues were investigated. The characterization of the MSWI bottom-ash samples examined by utilizing X-ray diffraction, optical microscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy. The experimental results show that as a function of thermal treatment, the reduction rate of Cl is slight below 15.0%, which is relatively low compared with water washing process. Different cooling methods had impacts on the existing forms of Cl. It was understood that most of Cl existed in the glass phase if the bottom ash was air cooled. Contrarily in case of water-quenched bottom ash, Cl could also be accumulated in the newly-formed quench products as chloride salts or hydrate substances such as Friedel's salt.

  9. MSWI bottom ash for thermal energy storage: an innovative and sustainable approach for its reutilization

    OpenAIRE

    Valle-Zermeño, Ricardo del; Barreneche Güerisoli, Camila; Cabeza, Luisa F.; Formosa, Joan; Fernández, Ana Inés; Chimenos, J. M.

    2016-01-01

    The management of Municipal Solid Waste (MSW) is a very important issue that must be dealt by the perspective of the 3 Rs (Reuse, reduce, recycle. MSW incineration bottom ash (BA) accounts for 85–95% of the total solids that remained after incineration. Finding suitable alternatives for its revalorization is very attractive, especially in terms of environmental sustainability. Thermal energy storage (TES) is a complementary technology of renewable energy. The aim of this study is to evaluate ...

  10. Investigations of physicochemical properties of bottom-ash materials for use them as secondary raw materials

    Science.gov (United States)

    Mal'chik, A. G.; Litovkin, S. V.; Rodionov, P. V.

    2015-09-01

    In this paper chemical content and particle size distribution of bottom-ash material are defined; results of differential thermal and X-ray analyzes are given; processes of phase transformations occurring during heating, are examined for possible use of the waste to produce ceramic products. Studies have shown that effective specific activity of radionuclides in the material under examination would have no effect on radiation safety of the finished product.

  11. Adsorption of Crystal Violet Dye from Aqueous Solution onto Zeolites from Coal Fly and Bottom Ashes

    Directory of Open Access Journals (Sweden)

    Tharcila Colachite Rodrigues Bertolini

    2013-11-01

    Full Text Available The adsorption of the cationic dye Crystal Violet (CV over zeolites from coal fly ash (ZFA and bottom ash (ZBA was evaluated. The coal fly ash (CFA and the coal bottom ash (CBA used in the synthesis of the zeolites by alkaline hydrothermal treatment were collected in Jorge Lacerda coal-fired power plant located at Capivari de Baixo County, in Santa Catarina State, Brazil. The zeolitic materials were characterized predominantly as hydroxy-sodalite and X. The dye adsorption equilibrium was reached after 10 min for ZFA and ZBA. The kinetics studies indicated that the adsorption followed the pseudo-second order kinetics and that surface adsorption and intraparticle diffusion were involved in the adsorption mechanism for both the adsorbents. The equilibrium data of ZFA was found to best fit to the Langmuir model, while ZBA was best explained by the Freundlich model. The maximum adsorption capacities were 19.6 mg g-1 for the CV/ZFA and 17.6 mg g-1 for the CV/ZBA.

  12. Removal of Mn(II) from the acid mine wastewaters using coal fired bottom ash

    Science.gov (United States)

    Mahidin, M.; Sulaiman, T. N.; Muslim, A.; Gani, A.

    2017-06-01

    Acid mine wastewater (AMW), the wastewater from mining activities which has low pH about 3-5 and contains hazardous heavy metals such as Cu, Fe, Mn, Zn, Pb, etc. Those heavy metals pollution is of prime concern from the environmental view point. Among the heavy metals, Mn occupies the third position in the AMW from one the iron ore mining company in Aceh, Indonesia. In this study, the possibility use of bottom ash from coal fired boiler of steam power plants for the removal of Mn(II) in AMW has been investigated. Experimental has been conducted as follows. Activation of bottom ash was done both by physical and chemical treatments through heating at 270 °C and washing with NaOH activator 0.5 and 1 M. Adsorption test contains two parts observation; preliminary and primary experiments. Preliminary study is addressed to select the best condition of three independent variables i.e.: pH of AMW (3 & 7), bottom ash particle size (40, 60 & 100 mesh) and initial Mn(II) concentrations (100 & 600 mg/l). AMW used was synthetics wastewater. It was found that the best value for NaOH is 1 M, pH is 7, particle size is 100 meshes and initial Mn(II) concentration is 600 mg/l from the adsorption efficiency point of view. The maximum adsorption capacity (q e) is 63.7 mg/g with the efficiency of 85%.

  13. Effect of electric arc vitrification of bottom ash on the mobility and fate of metals.

    Science.gov (United States)

    Ecke, H; Sakanakura, H; Matsuto, T; Tanaka, N; Lagerkvist, A

    2001-04-01

    Increasing amounts of municipal solid waste incineration (MSWI) residues are treated prior to landfilling or reuse. In Japan, electric arc melting is used for bottom ash vitrification that generates a glasslike slag. The objective of this paper was to assess this pretreatment technique with respect to its effect on metal mobility and metal content. Both bottom ash and slag were sampled and analyzed on total solids (TS), fixed solids (FS), particle density (pp), specific BET surface area, particle size distribution, and total element content. A six-step wet sequential extraction procedure was used for assessing metal mobility. The results were qualitatively verified by scanning electron microscopy. The major conclusion was that the availability of various metals was affected differently by electric arc vitrification. Metals were solidified, stabilized, and/or separated from the slag. The mobility of Cr, Cu, Zn, Pb, and Ca was reduced. In slag, majorfractions of these elements were found in moderately reducible phases or in the residual slag lattice. The approximately three-fourths of Pb [174 +/- 7 mg (kg of FS)-1] and half of Zn content [676 +/- 352 mg (kg of FS)-1] were most likely removed from bottom ash through evaporation. The total content increases of Al, Cr, Ni, and Cd (51 +/- 3, 621 +/- 27, 138 +/- 19, and 99 +/- 32%, respectively) were probably caused by the wear of furnace refractories.

  14. Properties of ceramics prepared using dry discharged waste to energy bottom ash dust.

    Science.gov (United States)

    Bourtsalas, Athanasios; Vandeperre, Luc; Grimes, Sue; Themelis, Nicolas; Koralewska, Ralf; Cheeseman, Chris

    2015-09-01

    The fine dust of incinerator bottom ash generated from dry discharge systems can be transformed into an inert material suitable for the production of hard, dense ceramics. Processing involves the addition of glass, ball milling and calcining to remove volatile components from the incinerator bottom ash. This transforms the major crystalline phases present in fine incinerator bottom ash dust from quartz (SiO(2)), calcite (CaCO(3)), gehlenite (Ca(2)Al(2)SiO(7)) and hematite (Fe(2)O(3)), to the pyroxene group minerals diopside (CaMgSi(2)O(6)), clinoenstatite (MgSi(2)O(6)), wollastonite (CaSiO(3)) together with some albite (NaAlSi(3)O(8)) and andradite (Ca(3)Fe(2)Si(3)O(12)). Processed powders show minimal leaching and can be pressed and sintered to form dense (>2.5 g cm(-3)), hard ceramics that exhibit low firing shrinkage (ceramic tiles that have potential for use in a range of industrial applications.

  15. Performance Appraisal of Controlled Low-strength Material Using Sewage Sludge and Refuse Incineration Bottom Ash

    Institute of Scientific and Technical Information of China (English)

    甄广印; 周海燕; 赵天涛; 赵由才

    2012-01-01

    This research evaluated the use of sewage sludge and refuse incineration bottom ash to replace calcium sulfoaluminate cement (CSA) in making controlled low-strength material (CLSM). Various properties of CLSM mixtures were characterized in terms of unconfined compressive strength, microstructure and leachability. It was found that the strength of tested CLSM mixtures ranged from 3.6 to 9.0 MPa, over the upper excavatable limit of 2.1 MPa. The micro-structural analysis revealed that sewage sludge and bottom ash were crystallochemically in- corporated within CLSM system_s by forming the needle-like ettringite (C3A'3CS'_H32) with exiguous tu.bers via the typical Pozzolanic Reaction, leading to a dense and low-porosity microst;'ucture. Furthermore,-the toxicity characteristic leaching procedure evidenced that the cumulative leachable metals in the leachate were much below the regulatory thresholds. The potential for us!ng sewage sludge and bottom ash!n CLSM makin.g was thus confirmed.

  16. Quantification of the resource recovery potential of municipal solid waste incineration bottom ashes

    Energy Technology Data Exchange (ETDEWEB)

    Allegrini, Elisa, E-mail: elia@env.dtu.dk [Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby (Denmark); Maresca, Alberto; Olsson, Mikael Emil [Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby (Denmark); Holtze, Maria Sommer [Afatek Ltd., Selinevej 18, 2300 Copenhagen S (Denmark); Boldrin, Alessio; Astrup, Thomas Fruergaard [Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby (Denmark)

    2014-09-15

    Highlights: • Ferrous and non-ferrous metals were quantified in MSWI bottom ashes. • Metal recovery system efficiencies for bottom ashes were estimated. • Total content of critical elements was determined in bottom ash samples. • Post-incineration recovery is not viable for most critical elements. - Abstract: Municipal solid waste incineration (MSWI) plays an important role in many European waste management systems. However, increasing focus on resource criticality has raised concern regarding the possible loss of critical resources through MSWI. The primary form of solid output from waste incinerators is bottom ashes (BAs), which also have important resource potential. Based on a full-scale Danish recovery facility, detailed material and substance flow analyses (MFA and SFA) were carried out, in order to characterise the resource recovery potential of Danish BA: (i) based on historical and experimental data, all individual flows (representing different grain size fractions) within the recovery facility were quantified, (ii) the resource potential of ferrous (Fe) and non-ferrous (NFe) metals as well as rare earth elements (REE) was determined, (iii) recovery efficiencies were quantified for scrap metal and (iv) resource potential variability and recovery efficiencies were quantified based on a range of ashes from different incinerators. Recovery efficiencies for Fe and NFe reached 85% and 61%, respectively, with the resource potential of metals in BA before recovery being 7.2%ww for Fe and 2.2%ww for NFe. Considerable non-recovered resource potential was found in fine fraction (below 2 mm), where approximately 12% of the total NFe potential in the BA were left. REEs were detected in the ashes, but the levels were two or three orders of magnitude lower than typical ore concentrations. The lack of REE enrichment in BAs indicated that the post-incineration recovery of these resources may not be a likely option with current technology. Based on these results

  17. Mineralogical characterization of municipal solid waste incineration bottom ash with an emphasis on heavy metal-bearing phases.

    Science.gov (United States)

    Wei, Yunmei; Shimaoka, Takayuki; Saffarzadeh, Amirhomayoun; Takahashi, Fumitake

    2011-03-15

    Municipal solid waste incineration (MSWI) bottom ash contains a considerable amount of heavy metals. The occurrence and uneven distribution of these heavy metals in bottom ash can increase the complexity of such residues in terms of long-term behavior upon landfilling or recycling. Bottom ashes sampled from three stoker-type incinerators in Japan were analyzed in this paper. This study presents detailed information on the mineralogical characterization of bottom ash constituents and the weathering behavior of these constituents by means of optical microscopy and scanning electron microscopy. It was revealed that bottom ash mainly consists of assorted silicate-based glass phases (48-54 wt% of ash) and mineral phases including melilites, pseudowollastonite, spinels, and metallic inclusions (Fe-P, Fe-S, Fe-Cu, Cu-Sn, Cu-Zn, Cu-S, and Cu-Pb dominated phases), as melt products formed during the incineration process. The compounds embedded in the glass matrix, e.g. spinels and metallic inclusions, played the most important role in concentration of heavy metals (Pb, Zn, Cu, Cr, Mn, Ni, etc.). Other phases such as refractory minerals and ceramics, frequently found in ash, were of less significance in terms of their influence on the involvement of heavy metals. Analysis of lab-scale artificially weathered and 10-year landfilled bottom ash samples revealed that secondary mineralization/alteration of the bottom ash constituents principally carbonation and glass evolution substantially decreased the potential risk of the heavy metals to the surrounding environment. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Stimulation of methane oxidation potential and effects on vegetation growth by bottom ash addition in a landfill final evapotranspiration cover.

    Science.gov (United States)

    Kim, Gil Won; Ho, Adrian; Kim, Pil Joo; Kim, Sang Yoon

    2016-09-01

    The landfilling of municipal solid waste is a significant source of atmospheric methane (CH4), contributing up to 20% of total anthropogenic CH4 emissions. The evapotranspiration (ET) cover system, an alternative final cover system in waste landfills, has been considered to be a promising way to mitigate CH4 emissions, as well as to prevent water infiltration using vegetation on landfill cover soils. In our previous studies, bottom ash from coal-fired power plants was selected among several industrial residues (blast furnace slag, bottom ash, construction waste, steel manufacture slag, stone powder sludge, and waste gypsum) as the best additive for ET cover systems, with the highest mechanical performance achieved for a 35% (wtwt(-1)) bottom ash content in soil. In this study, to evaluate the field applicability of bottom ash mixed soil as ET cover, four sets of lysimeters (height 1.2m×width 2m×length 6m) were constructed in 2007, and four different treatments were installed: (i) soil+bottom ash (35% wtwt(-1)) (SB); (ii) soil+compost (2% wtwt(-1), approximately corresponding to 40Mgha(-1) in arable field scale) (SC); (iii) soil+bottom ash+compost (SBC); and (iv) soil only as the control (S). The effects of bottom ash mixing in ET cover soil on CH4 oxidation potential and vegetation growth were evaluated in a pilot ET cover system in the 5th year after installation by pilot experiments using the treatments. Our results showed that soil properties were significantly improved by bottom ash mixing, resulting in higher plant growth. Bottom ash addition significantly increased the CH4 oxidation potential of the ET cover soil, mainly due to improved organic matter and available copper concentration, enhancing methanotrophic abundances in soil amended with bottom ash. Conclusively, bottom ash could be a good alternative as a soil additive in the ET cover system to improve vegetation growth and mitigate CH4 emission impact in the waste landfill system. Copyright © 2016

  19. Effect of kaolin addition on the performance of controlled low-strength material using industrial waste incineration bottom ash.

    Science.gov (United States)

    Naganathan, Sivakumar; Razak, Hashim Abdul; Hamid, Siti Nadzriah Abdul

    2010-09-01

    Incineration of industrial waste produces large quantities of bottom ash which are normally sent to secured landfill, but is not a sustainable solution. Use of bottom ash in engineering applications will contribute to sustainability and generate revenue. One way of using the industrial waste incineration bottom ash is in controlled low-strength material (CLSM). Use of bottom ash in CLSM has problems related to bleeding and excessive strength development and so an additive has to be used to control bleeding and strength development. The main objective of this research is to study the effect of kaolin addition on the performance of CLSM made using industrial waste incineration bottom ash. CLSM mixes were made with bottom ash, cement, and refined kaolin. Various tests were performed on the CLSM in fresh and hardened states including compressive strength, water absorption, California bearing ratio (CBR) and the tests for concentration of leachable substances on the bleed and leachate. The compressive strength of CLSM tested ranged from 0.11 to 9.86 MPa. CBR values ranged from 6 to 46, and water absorption values from 12 to 36%. It was shown that the addition of kaolin delayed the initial setting time of CLSM mixtures, reduced bleeding, lowered the compressive strength, and increased the values of water absorption, sorption, and initial surface absorption. The CLSM tested did not have corrosivity. It was shown that the hardened CLSM was non hazardous, and the addition of kaolin increased the concentration of heavy metals and salts in the bleed and leachate.

  20. A top-bottom price approach to understanding financial fluctuations

    Science.gov (United States)

    Rivera-Castro, Miguel A.; Miranda, José G. V.; Borges, Ernesto P.; Cajueiro, Daniel O.; Andrade, Roberto F. S.

    2012-02-01

    The presence of sequences of top and bottom (TB) events in financial series is investigated for the purpose of characterizing such switching points. They clearly mark a change in the trend of rising or falling prices of assets to the opposite tendency, are of crucial importance for the players' decision and also for the market stability. Previous attempts to characterize switching points have been based on the behavior of the volatility and on the definition of microtrends. The approach used herein is based on the smoothing of the original data with a Gaussian kernel. The events are identified by the magnitude of the difference of the extreme prices, by the time lag between the corresponding events (waiting time), and by the time interval between events with a minimal magnitude (return time). Results from the analysis of the inter day Dow Jones Industrial Average index (DJIA) from 1928 to 2011 are discussed. q-Gaussian functions with power law tails are found to provide a very accurate description of a class of measures obtained from the series statistics.

  1. Long-term Performance of MSWI Bottom Ash in a Test Road Construction

    Directory of Open Access Journals (Sweden)

    Paul Christian Frogner-Kockum

    2016-02-01

    Full Text Available The study focuses on long-term performances of MSWI bottom ash used as a reinforcement layer in a 8 years old road-construction. Long term properties may change under the combined effects of loading, climate- and chemical conditions. Characterization of the chemical changes in aged MSWI bottom ash is thus of prime interest as secondary alteration is a key process for the ageing of these kind of materials. The MSWI bottom ash in this study comprises a 60 meter-long segment of a test road, which was sampled eight years after construction. The objective of the sampling was to obtain a very low degree of disturbance to the application’s in-situ properties. Access to the sub-base was achieved by removing the surface course and unbound base course, leaving the top surface of the unbound sub-base reachable.  Epoxy impregnated slabs were also used for a micro textural and chemical characterization by SEM/EDS of the bottom ash sub-base layer. No cracks that imply movements or rotation of particles in the road construction or other disturbances as due to the sampling process were found. This undisturbed material made it possible to study chemical processes and structural changes that have been ongoing in the test road since it was constructed. The SEM/EDS analysis showed that most particles had reacted to some extent and that reaction-products surrounding aluminum particles were undisturbed. Partly decomposed particles indicate that the reaction (that has been ongoing since the road was constructed has been slow and incomplete because of the coexistence of metallic aluminum and aluminum hydroxide. It also shows that the material not has been subjected to any physical influence during these 8 years that otherwise would have moved the reaction products from the particles that originally have reacted. Clay mineralization that indicates long-term ageing of the ash material was also detected by XRPD. The pH of the material was lower than 8.5, indicating a

  2. Characterization of bottom ash from two hospital waste incinerators in Rabat, Morocco.

    Science.gov (United States)

    Bakkali, Meriem E L; Bahri, Meriem; Gmouh, Said; Jaddi, Hassan; Bakkali, Mohammed; Laglaoui, Amin; Mzibri, Mohammed E L

    2013-12-01

    The uncontrolled disposal of bottom ash generated by the incineration units of hazardous and infected wastes in developed countries are the main cause of significant damage, such as contamination of the soil, as well as surface and underground waters, which may put both the environment and public health at risk. In Morocco, little information is available on the chemical properties of the resulting ashes. In this study, 16 hospital waste ash samples were collected from the incinerators of the two main hospitals in Rabat: Ibn Sina and Cheikh Zayd. A series of tests was conducted, including particle size distribution, mineralogical and chemical composition, and heavy metal leaching behaviour. The results showed that the samples were composed mainly of P2O5 (18%), SiO2 (17%), Na2O (16%), CaO (14%) and SO3 (10%). Moreover, chemical analysis clearly demonstrated that medical waste (MW) contains large amounts of waste generated by domestic activities in the hospital, with a lack of sorting system in the monitoring of MW. Furthermore, the ashes contained high concentrations of heavy metals such as zinc, lead, chromium and nickel with a vast range of 0.5-25071 mg/kg. Leaching tests showed that the extracted amounts of all the heavy metals were lower, with concentrations waste acceptance criteria regarding these heavy metals.

  3. New methodology for assessing the environmental burden of cement mortars with partial replacement of coal bottom ash and fly ash.

    Science.gov (United States)

    Menéndez, E; Álvaro, A M; Hernández, M T; Parra, J L

    2014-01-15

    This paper assess the mechanical an environmental behaviour of cement mortars manufactured with addition of fly ash (FA) and bottom ash (BA), as partial cement replacement (10%, 25% and 35%). The environmental behaviour was studied by leaching tests, which were performed under several temperature (23 °C and 60 °C) and pH (5 and 10) conditions, and ages (1, 2, 4 and 7 days). Then, the accumulated amount of the different constituents leached was analysed. In order to obtain an environmental burden (EB) value of each cement mixture, a new methodology was developed. The EB value obtained is related to the amount leached and the hazardous level of each constituent. Finally, the integral study of compressive strength and EB values of cement mixtures allowed their classification. The results showed that mortars manufactured with ordinary Portland cement (OPC) and with coal BA had similar or even better environmental and mechanical behaviour than mortars with FA. Therefore, the partial replacement of cement by BA might be as suitable or even better as the replacement by FA.

  4. Influence of natural pozzolan, colemanite ore waste, bottom ash, and fly ash on the properties of Portland cement

    Energy Technology Data Exchange (ETDEWEB)

    Targan, S.; Olgun, A.; Erdogan, Y.; Sevinc, V. [Dumlupinar University, Kutahya (Turkey). Dept. of Chemistry

    2003-08-01

    The effect of natural pozzolan (NP), colemanite ore waste (CW), coal fly ash (FA), and coal bottom ash (BA) on the properties of cement and concrete was examined. The parameters studied included compressive strength, bending strength, volume expansion, and setting time. A number of cements were prepared (in the presence of fixed quantity of 10% FA, 10% BA, and 4% CW) by the replacement of Portland cement (PC) with NP in range of 5 - 30%. The results showed that the final setting time of cement pastes were generally accelerated when the NP replaced part of the cement. However, NP exhibited a significant retarding effect when used in combination with CW. The results also showed that the inclusion of NP at replacement levels of 5% resulted in an increase in compressive strength of the specimens compared with that of the control concrete. The replacement of PC by 10 - 15% of NP in the presence of fixed quantity of CW improves the bending strength of the specimens compared with control specimens after 60 days of curing age.

  5. An investigation on the use of tincal ore waste, fly ash, and coal bottom ash as Portland cement replacement materials

    Energy Technology Data Exchange (ETDEWEB)

    Kula, I.; Olgun, A.; Sevinc, V.; Erdogan, Y. [Dumlupinar University, Kutahya (Turkey). Dept. of Chemistry

    2002-02-01

    The possibility of using tincal ore waste (TW), coal bottom ash (BA), and fly ash (FA) as partial replacement in concrete was examined through a number of tests. The properties examined include setting time, compressive strength, mortar expansion, water consistency of mortar, and microstructure. The results showed that compressive strength of all specimens containing 1 wt.% of TW was higher than that of the control at the 28th day of curing. At 90 days, the contribution to strength by BA + TW and FA + TW was higher than in the concrete-prepared equivalent TW beyond 3 wt.% of Portland cement (PC) replacement. With the replacement of 3-5 wt.% of PC by TW, the compressive strength of the concrete decreased compared to control concrete. However, the values obtained are within the limit of Turkish Standards. Adding BA or FA with TW improved the performance relative to TW replacement only. Increasing replacement of TW gives rise to a higher setting time. As a result. TW, BA, and FA samples may be used as cementitious materials.

  6. The relationship between mineral contents, particle matter and bottom ash distribution during pellet combustion: molar balance and chemometric analysis.

    Science.gov (United States)

    Jeguirim, Mejdi; Kraiem, Nesrine; Lajili, Marzouk; Guizani, Chamseddine; Zorpas, Antonis; Leva, Yann; Michelin, Laure; Josien, Ludovic; Limousy, Lionel

    2017-03-21

    This paper aims to identify the correlation between the mineral contents in agropellets and particle matter and bottom ash characteristics during combustion in domestic boilers. Four agrifood residues with higher mineral contents, namely grape marc (GM), tomato waste (TW), exhausted olive mill solid waste (EOMSW) and olive mill wastewater (OMWW), were selected. Then, seven different pellets were produced from pure residues or their mixture and blending with sawdust. The physico-chemical properties of the produced pellets were analysed using different analytical techniques, and a particular attention was paid to their mineral contents. Combustion tests were performed in 12-kW domestic boiler. The particle matter (PM) emission was characterised through the particle number and mass quantification for different particle size. The bottom ash composition and size distribution were also characterised. Molar balance and chemometric analyses were performed to identify the correlation between the mineral contents and PM and bottom ash characteristics. The performed analyses indicate that K, Na, S and Cl are released partially or completely during combustion tests. In contrast, Ca, Mg, Si, P, Al, Fe and Mn are retained in the bottom ash. The chemometric analyses indicate that, in addition to the operating conditions and the pellet ash contents, K and Si concentrations have a significant effect on the PM emissions as well as on the agglomeration of bottom ash.

  7. Effect of accelerated carbonation and zero valent iron on metal leaching from bottom ash.

    Science.gov (United States)

    Nilsson, M; Andreas, L; Lagerkvist, A

    2016-05-01

    About 85% of the ashes produced in Sweden originated from the incineration of municipal solid waste and biofuel. The rest comes from the thermal treatment of recycled wood, peat, charcoal and others. About 68% of all ashes annually produced in Sweden are used for constructions on landfills, mainly slopes, roads and embankments, and only 3% for construction of roads and working surfaces outside the landfills (SCB, 2013). Since waste bottom ash (BA) often has similar properties to crushed bedrock or gravel, it could be used for road constructions to a larger extent. However, the leaching of e.g. Cr, Cu, Mo, Pb and Zn can cause a threat to the surrounding environment if the material is used as it is. Carbonation is a commonly used pre-treatment method, yet it is not always sufficient. As leaching from aged ash is often controlled by adsorption to iron oxides, increasing the number of Fe oxide sorption sites can be a way to control the leaching of several critical elements. The importance of iron oxides as sorption sites for metals is known from both mineralogical studies of bottom ash and from the remediation of contaminated soil, where iron is used as an amendment. In this study, zero valent iron (Fe(0)) was added prior to accelerated carbonation in order to increase the number of adsorption sites for metals and thereby reduce leaching. Batch, column and pHstat leaching tests were performed and the leaching behaviour was evaluated with multivariate data analysis. It showed that leaching changed distinctly after the tested treatments, in particular after the combined treatment. Especially, the leaching of Cr and Cu clearly decreased as a result of accelerated carbonation. The combination of accelerated carbonation with Fe(0) addition reduced the leaching of Cr and Cu even further and reduced also the leaching of Mo, Zn, Pb and Cd compared to untreated BA. Compared with only accelerated carbonation, the Fe(0) addition significantly reduced the leaching of Cr, Cu and Mo

  8. Improved electrical efficiency and bottom ash quality on waste combustion plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Peter A.; Nesterov, I.; Boejer, M.; Hyks, J.; Astrup, T.; Kloeft, H.; Dam-Johansen, K.; Lundtorp, K.; Hedegaard Madsen, O.; Frandsen, F. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Mogensen, Erhardt (Babcock and Wilcox Voelund A/S, Glostrup (Denmark))

    2010-07-01

    Investigations making it possible to evaluate and further develop concepts to improve electrical efficiency in a waste combustion plant were performed. Furthermore, one objective of the study was to investigate the possibilities of improving waste bottom ash leaching properties by use of a rotary kiln treatment. The project work included construction of a bench-scale rotary kiln, performing ash rotary kiln treatment experiments, conducting gas suction probe measurements on a waste incineration plant and making some concept evaluations. The influence of the rotary kiln thermal treatment on the leaching of Ca, Al, Si, Mg, Ba, Sr, Cl, Cu, Pb, Zn, Cr, Mo, sulfate, DOC and carbonate was determined. As a result of these tests, the rotary kiln thermal treatment of bottom ashes can be recommended for reducing the leaching of Cu, Pb, Cl, Zn and DOC; however, an increased leaching of Cr and Mo should be expected. The combustion conditions above the grate of a waste incineration plant were investigated and the release and concentration of volatile ash species in the flue gas such as Cl, Na, K, Ca, Pb, Zn and S were measured. The conducted measurements show that flue gas from grate sections 3 and 4 can produce a sufficiently hot flue gas that contains only low concentrations of corrosive species, and therefore can be used to increase superheater temperatures. Implementation of the so-called flue gas split concept together with other steam circle modifications on a waste combustion plant, and using a reasonable increase in final steam temperature from 400 to 500 deg. C, have the potential to increase electrical efficiency from 24 to 30% (with respect to lower fuel heating value) in a waste combustion plant. (Author)

  9. Monitoring the species of arsenic, chromium and nickel in milled coal, bottom ash and fly ash from a pulverized coal-fired power plant in western Canada.

    Science.gov (United States)

    Goodarzi, F; Huggins, F E

    2001-02-01

    The concentration of As, Cr and Ni and their speciation (As3+;5+, Cr3+;6+ and Ni0;2+) in milled coal, bottom ash and ash collected by electrostatic precipitator (ESP) from a coal fired-power plant in western Canada were determined using HGAAS, ICP-AES and XANES. The chemical fractionation of these elements was also determined by a sequential leaching procedure, using deionized water, NH4OAC and HCI as extracting agents. The leachate was analyzed by ICP-AES. Arsenic in the milled coal is mostly associated with organic matter, and 67% of this arsenic is removed by ammonium acetate. This element is totally removed from milled coal after extraction with HCI. Arsenic occurs in both the As3+ and the As5+ oxidation states in the milled coal, while virtually all (>90%) of the arsenic in bottom ash and fly ash appears to be in the less toxic arsenate (As5+) form. Both Ni and Cr in the milled coal are extracted by HCI, indicating that water can mobilize Ni and Cr in an acidic environment. The chromium is leached by water from fly ash as a result of the high pH of the water, which is induced during the leaching. Ammonium acetate removes Ni from bottom ash through an ion exchange process. Chromium in milled coal is present entirely as Cr3+, which is an essential human trace nutrient. The Cr speciation in bottom ash is a more accentuated version of the milled coal and consists mostly of the Cr3+ species. Chromium in fly ash is mostly Cr3+, with significant contamination by stainless-steel from the installation itself.

  10. The weathering of municipal solid waste incineration bottom ash evaluated by some weathering indices for natural rock.

    Science.gov (United States)

    Takahashi, Fumitake; Shimaoka, Takayuki

    2012-12-01

    The weathering of municipal solid waste incineration (MSWI) residues consists of complicated phenomena. This makes it difficult to describe leaching behaviors of major and trace elements in fresh/weathered MSWI bottom ash, which was relevant interactively to pH neutralization and formation of secondary minerals. In this study, mineralogical weathering indices for natural rock profiles were applied to fresh/landfilled MSWI bottom ash to investigate the relation of these weathering indices to landfill time and leaching concentrations of component elements. Tested mineralogical weathering indices were Weathering Potential Index (WPI), Ruxton ratio (R), Weathering Index of Parker (WIP), Vogt's Residual Index (V), Chemical Index of Alternation (CIA), Chemical Index of Weathering (CIW), Plagioclase Index of Alternation (PIA), Silica-Titania Index (STI), Weathering Index of Miura (Wm), and Weatherability index of Hodder (Ks). Welch's t-test accepted at 0.2% of significance level that all weathering indices could distinguish fresh and landfilled MSWI bottom ash. However, R and STI showed contrasted results for landfilled bottom ash to theoretical expectation. WPI, WIP, Wm, and Ks had good linearity with reclamation time of landfilled MSWI bottom ash. Therefore, these four indices might be applicable as an indicator to identify fresh/weathered MSWI bottom ash and to estimate weathering time. Although WPI had weak correlation with leachate pH, other weathering indices had no significant correlation. In addition, all weathering indices could not explain leaching concentration of Al, Ca, Cu, and Zn quantitatively. Large difficulty to modify weathering indices correctly suggests that geochemical simulation including surface sorption, complexation with DOM, and other mechanisms seems to be the only way to describe leaching behaviors of major and trace elements in fresh/weathered MSWI bottom ash. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. A comparative study of geopolymers synthesized from OXY-combustion and chemical looping combustion bottom ashes

    CSIR Research Space (South Africa)

    Nkuna, CN

    2017-04-01

    Full Text Available Fourier transformation infrared spectroscopy (FTIR) was performed with a Perkin Elmer 133 spectrum RX FT-IR system, the samples were analyzed using the KBr pellet technique (3mg 134 powder sample mixed with 100mg of KBr) [16]. Thermo-gravimetric analysis... for the blending of a more reactivity material such as metakaolin with 365 FBC, OXY-FBC and CLC bottom ashes in the production of geopolymer for binders in the 366 construction industry. This is due to an incomplete formation of a dense N-A-S-H gel, hence 367 a...

  12. 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.

  13. Feasibility of manufacturing geopolymer bricks using circulating fluidized bed combustion bottom ash.

    Science.gov (United States)

    Chen, Chen; Li, Qin; Shen, Lifeng; Zhai, Jianping

    2012-06-01

    This paper presents a study on geopolymer bricks manufactured using bottom ash from circulating fluidized bed combustion (CFBC). The alkali activators used for synthesis were sodium silicate, sodium hydroxide, and potassium hydroxide and lithium hydroxide solutions. The study included the impact of alkali activator on compressive strength. The reaction products were analysed by XRD, FT-IR and SEM/EDS. The compressive strength of bricks was dependent on the modulus of the sodium silicate activator and the type and concentration of alkali activator. The highest compressive strength could be gained when the modulus was 1.5, and the value could reach 16.1 MPa (7 d after manufacture) and 21.9 MPa (28 d after manufacture). Under pure alkaline systems, the compressive strength was in the order of 10 M KOH > 10 M NaOH > 5 M LiOH > 5 M KOH > 5 M NaOH. Quartz was the only crystalline phase in the original bottom ash, and no new crystalline phase was found after the reaction. The main product of reaction was amorphous alkali aluminosilicate gel and a small amount of crystalline phase was also found by SEM.

  14. Effects of Coal Combustion Additives on the Forms and Recovery of Uranium in Coal Bottom Ash

    Science.gov (United States)

    Tang, Ye; Li, Yilian

    2017-04-01

    Recovering uranium from uranium-rich coal ash is an important way to utilize unconventional uranium resource. Although it might be expected that the uranium in residual form would prevent uranium recovery from coal ash, raising the recovery rate in way of controlling residual uranium has not yet been studied. In this study, three different kinds of combustion promoting additives were investigated by coal combustion experiments, in order to decrease the proportion of residual-form uranium in ash and increase the acid leaching rate. Analytical procedures included Tessier sequential extraction, acidleaching, and characterization(ICP-MS, XRF, BET and SEM-EDS). It was showed that the effects of additives in reducing residual uranium were as the following order: alkaline earth metal compounds > transition metal compounds> alkali metal compounds. Adding alkali metal additives(KCl, NaCl, K2CO3, Na2CO3) raised the percentage of residual uranium largely. Additionally, one transition metal additive(Fe2O3) reached a decreasing amplitude of 5.15%, while the other two additives(MnO2 and Fe3O4)made the rates increased. However, coal combustion with alkaline earth metal compounds mixed had target effects. Among this kind of additives(Ca(OH)2, CaCO3, CaO, CaCl2), CaCO3displayed the best effect on restricting the rising proportion of residual uranium by 18%. Moreover, the leaching recovery research indicated that CaCO3 could raise the recovery rate by 10.8%. The XRF profiles supported that the CaCO3 could lower the concentration of SiO2 in the bottom ash from 79.76% to 49.69%. Besides, The BET and SEM revealed that the decomposition of CaCO3 brought about a variation of surface structures and area, which promoted the contact between the leaching agent and bottom ash. The uranium content increase was determined by ICP-MS and EDS. These findings suggest that CaCO3 could be a favorable additive for the controlling of residual uranium and improvement of uranium recovery rates. Key words

  15. Removal of vertigo blue dyes from Batik textile wastewater by adsorption onto activated carbon and coal bottom ash

    Science.gov (United States)

    Kusmiyati, L., Puspita Adi; Deni, V.; Robi Indra, S.; Islamica, Dlia; Fuadi, M.

    2016-04-01

    Removal of vertigo blue dye from batik textile wastewater was studied by adsorptionprocess onto activated carbon (AC) and coal bottom ash (CBA).The influence of experimental conditions (pH solution, dye concentration, and contact time) were studied on the both adsorbents. At equilibrium conditions, the data were fitted to Langmuir and Freundlich adsorption models. The maximum adsorption capacity calculated from the Langmuir model for carbon active was 6.29mg/g at pH that found to be considerably higher than that obtained for coal bottom ash 3.72mg/g pH 9. From Freundlich model, the maximum adsorption capacity is less for coal bottom ash (pH 9) than that for carbon active (pH4).

  16. Stabilization/solidification of fly ashes and concrete production from bottom and circulating ashes produced in a power plant working under mono and co-combustion conditions.

    Science.gov (United States)

    Barbosa, Rui; Lapa, Nuno; Lopes, Helena; Gulyurtlu, Ibrahim; Mendes, Benilde

    2011-01-01

    Two combustion tests were performed in a fluidized bed combustor of a thermo-electric power plant: (1) combustion of coal; (2) co-combustion of coal (68.7% w/w), sewage sludge (9.2% w/w) and meat and bone meal (MBM) (22.1% w/w). Three samples of ashes (bottom, circulating and fly ashes) were collected in each combustion test. The ashes were submitted to the following assays: (a) evaluation of the leaching behaviour; (b) stabilization/solidification of fly ashes and evaluation of the leaching behaviour of the stabilized/solidified (s/s) materials; (c) production of concrete from bottom and circulating ashes. The eluates of all materials were submitted to chemical and ecotoxicological characterizations. The crude ashes have shown similar chemical and ecotoxicological properties. The s/s materials have presented compressive strengths between 25 and 40 MPa, low emission levels of metals through leaching and were classified as non-hazardous materials. The formulations of concrete have presented compressive strengths between 12 and 24 MPa. According to the Dutch Building Materials Decree, some concrete formulations can be used in both scenarios of limited moistening and without insulation, and with permanent moistening and with insulation.

  17. The Characteristics of Asphalt Concrete Binder Course (AC-BC Mixture with Bottom Ash as Aggregate Substitute

    Directory of Open Access Journals (Sweden)

    Sugiyanto G.

    2015-01-01

    Full Text Available Highways serve nearly 80-90% of the population mobility and flow of goods. Utilization of bottom ash, a waste from coal combustion, in highway construction is one of the alternatives to reduce environmental pollution and support Clean Development Mechanism Program of Kyoto Protocol. The aim of this study is to analyze the characteristics of AC-BC mixture that uses bottom ash as partial substitute of fine aggregate and comparing with a standard mixture. Laboratory tests are performed on two different types of mixtures. The tests show that optimum asphalt content for AC-BCStandard mixture is 5.20% while AC-BCBottom Ash mixture is 5.25%. Bottom ash has higher porosity along with a little break field and has round shape so that the asphalt absorption is bigger than the crushed stone. Bottom ash can be used as an alternative aggregate to increase the value of flow of the AC-BC mixture, thus converting waste to valuable material.

  18. The use of the bottom ashes and of the steelmaking slags in the manufacturing technologies of the building materials

    Directory of Open Access Journals (Sweden)

    L. G. Popescu

    2016-07-01

    Full Text Available The energetic and metallurgy industries of Romania represent the main waste sources significant from the point of quantitative view: the bottom ashes and the blast furnace and secondary metallurgical slags. Starting from the knowledge of the main chemical-physical properties of these two types of industrial wastes, there were inquired the exploitation possibilities in the technological practice, by using in the manufacturing of some building materials, for which these wastes represent the exclusive raw material source. The experiments considered the granular aggregate properties of the bottom ash and of the blast furnace slag, completed by the hydraulic binder of the secondary metallurgical slag, after the fine crushing.

  19. Wood pellet fly ash and bottom ash as an effective liming agent and nutrient source for rye grass (Lolium perenne L.) and oats (Avena sativa).

    Science.gov (United States)

    Park, Nathan D; Michael Rutherford, P; Thring, Ronald W; Helle, Steve S

    2012-01-01

    Fly ash (FA) and bottom ash (BA) from a softwood pellet boiler were characterized and evaluated as soil amendments. In a greenhouse study, two plant species (rye grass, Lolium perenne L. and oats, Avena sativa) were grown in three different treatments (1% FA, 1% BA, non-amended control) of a silty loam soil. Total concentrations of plant nutrients Ca, K, Mg, P and Zn in both ashes were elevated compared to conventional wood ash. Concentrations of Cd, Cr, Pb, Se and Zn were found to be elevated in the FA relative to BA and the non-amended soil. At 28 d, oat above-ground biomass was found to be significantly greater in soil amended with FA. Potassium and Mo plant tissue concentrations were significantly increased by addition of either ash, and FA significantly increased Zn tissue concentrations. Cadmium and Hg tissue concentrations were elevated in some cases. As soil amendments, either pellet ash is an effective liming agent and nutrient source, but high concentrations of Cd and Zn in FA may preclude its use as an agricultural soil amendment in some jurisdictions. Lower ash application rates than those used in this study (i.e. <1%) may still provide sufficient nutrients and effective neutralization of soil acidity.

  20. Exposure to toxicants in soil and bottom ash deposits in Agbogbloshie, Ghana: human health risk assessment.

    Science.gov (United States)

    Obiri, S; Ansa-Asare, O D; Mohammed, S; Darko, H F; Dartey, A G

    2016-10-01

    Recycling of e-waste using informal or crude techniques poses serious health risk not only to the workers but also to the environment as whole. It is against this background that this paper sought to measure health risk faced by informal e-waste workers from exposure to toxicants such as lead, cadmium, chromium, copper, arsenic, tin, zinc and cobalt via oral and dermal contact with bottom ash and soil. Using random sampling techniques, 3 separate sites each (where burning and manual dismantling of e-wastes are usually carried) were identified, and a total of 402 samples were collected. The samples were analysed using standard methods for chemical analysis prescribed by the American Water Works Association (AWWA). Concentrations of Pb, Cd, Cr, Cu, As, Sn, Zn and Co in bottom ash samples from location ASH1 are 5388 ± 0.02 mg/kg (Pb), 2.39 ± 0.01 mg/kg (Cd), 42 ± 0.05 mg/kg (Cr), 7940 ± 0.01 mg/kg (Cu), 20 ± 0.07 mg/kg (As), 225 ± 0.04 mg/kg (Sn), 276 ± 0.04 mg/kg (Zn) and 123 ± 0.04 mg/kg (Co), while concentrations of the aforementioned toxicants in soil samples at location ASG1 are as follows: 1685 ± 0.14 mg/kg (Pb), 26.89 ± 0.30 mg/kg (Cd), 36.86 ± 0.02 mg/kg (Cr), 1427 ± 0.08 mg/kg (Cu), 1622 ± 0.12 mg/kg (As), 234 ± 0.25 mg/kg (Sn), 783 ± 0.31 mg/kg (Zn) and 135 ± 0.01 mg/kg (Co); used as input parameters in assessing health risk faced by workers. The results of cancer health risk faced by e-waste workers due to accidental ingestion of As in bottom ash at ASH1 is 4.3 × 10(-3) (CTE) and 6.5 × 10(-2) (RME), i.e. approximately 4 out of 1000 e-waste workers are likely to suffer from cancer-related diseases via central tendency exposure (CTE parameters), and 7 out of every 100 e-waste worker is also likely to suffer from cancer cases by reasonable maximum exposure (RME) parameters, respectively. The cancer health risk results for the other sampling sites were found to have exceeded the acceptable

  1. Comparison of activated carbon and bottom ash removal of reactive dye from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Dincer, A.R.; Gunes, Y.; Karakaya, N.; Gunes, E. [Trakya University, Tekirdag (Turkey). Dept. of Environmental Engineering

    2007-03-15

    The adsorption of reactive dye from synthetic aqueous solution onto granular activated carbon (GAC) and coal-based bottom ash (CBBA) were studied under the same experimental conditions. As an alternative to GAC CBBA was used as adsorbent for dye removal from aqueous solution. The amount of Vertigo Navy Marine (VNM) adsorbed onto CBBA was lower compared with GAC at equilibrium and dye adsorption capacity increased from 0.71 to 3.82 mg g{sup -1}, and 0.73 to 6.35 mg g{sup -1} with the initial concentration of dye from 25 to 300 mg l{sup -1} respectively. The initial dye uptake of CBBA was not so rapid as in the case of GAC and the dye uptake was slow and gradually attained equilibrium.

  2. LCA of management strategies for RDF incineration and gasification bottom ash based on experimental leaching data

    DEFF Research Database (Denmark)

    Gianfilippo, Martina Di; Costa, Giulia; Pantini, Sara

    2016-01-01

    The main characteristics and environmental properties of the bottom ash (BA) generated from thermal treatment of waste may vary significantly depending on the type of waste and thermal technology employed. Thus, to ensure that the strategies selected for the management of these residues do...... not cause adverse environmental impacts, the specific properties of BA, in particular its leaching behavior, should be taken into account. This study focuses on the evaluation of potential environmental impacts associated with two different management options for BA from thermal treatment of Refuse Derived...... Fuel (RDF): landfilling and recycling as a filler for road sub bases. Two types of thermal treatment were considered: incineration and gasification. Potential environmental impacts were evaluated by life-cycle assessment (LCA) using the EASETECH model. Both non-toxicity related impact categories (i...

  3. Hazard remediation and recycling of tea industry and paper mill bottom ash through vermiconversion.

    Science.gov (United States)

    Goswami, Linee; Patel, Arbind Kumar; Dutta, Ganesh; Bhattacharyya, Pradip; Gogoi, Nirmali; Bhattacharya, Satya Sundar

    2013-07-01

    Considerable amount of bottom ash (BA) is produced by tea and paper factories in Northeast India. This significantly deteriorates soil and surface water quality through rapid acidification, releasing sulfur compounds and heavy metals. The present investigation endeavoured to convert this waste to organic manure through vermicomposting by Eisenia fetida. Substantial increment in bioavailability of N, P, K, Fe, Mn and Zn along with remarkable decline in toxic metal like Cr due to vermicomposting was noteworthy. Furthermore, vermicomposted mixtures of Tea Factory BA (TFBA) or Paper Mill BA (PMBA) with organic matter (OM) attributed profuse pod yield of French Bean (Phaseolus vulgaris L.). Hence, bioconversion of TFBA and PMBA is highly feasible through vermicomposting and the converted materials can be utilized as potential organic fertilizer.

  4. Life cycle assessment of resource recovery from municipal solid waste incineration bottom ash

    DEFF Research Database (Denmark)

    Allegrini, Elisa; Vadenbo, Carl; Boldrin, Alessio

    2015-01-01

    Bottom ash, the main solid output from municipal solid waste incineration (MSWI), has significant potential for the recovery of resources such as scrap metals and aggregates. The utilisation of these resources ideally enables natural resources to be saved. However, the quality of the recovered...... breakeven points beyond which the burdens of the recovery processes outweigh the environmental benefits from valorising metals and mineral aggregates. Experimental data for the quantity and quality of individual material fractions were used as a basis for LCA modelling. For the aggregates, three disposal...... routes were compared: landfilling, road sub-base and aggregate in concrete, while specific leaching data were used as the basis for evaluating toxic impacts. The recovery and recycling of aluminium, ferrous, stainless steel and copper scrap were considered, and the importance of aluminium scrap quality...

  5. Testing the possibility for reusing mswi bottom ash in Greenlandic road construction

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Jørgensen, Anders Stuhr; Villumsen, Arne

    2012-01-01

    In Greenland waste has traditionally been dumped at open disposal sites combined with uncontrolled incineration. In the mid 1990’ties the first waste strategy was implemented in Greenland. As a result simple and small municipal solid waste incineration (MSWI) plants were implemented in towns...... and settlements primarily to minimize the amount of waste at the disposal sites. In Greenland the household waste is generally sorted into four fractions [1]: combustible, metal, hazardous waste and mixed waste and there are problems of sorting the metal and hazardous waste properly from the combustible waste...... as filler in roads [3]. Thus, pretreatment or better sorting of the waste before incineration is necessary to improve the quality of the bottom ash before reuse as road fill is possible. References [1] Eisted, R., Christensen, T.H.: Waste management in Greenland: Current situation and challenges. Waste...

  6. Bioaccumulations of heavy metals in Ipomoea aquatica grown in bottom ash recycling wastewater.

    Science.gov (United States)

    Milla, Odette Varela; Rivera, Eva B; Huang, Wu-Jang

    2014-05-01

    A plant bioassay using hydroponically grown Ipomoea aquatica (water spinach) was applied to assess the phytotoxicity of untreated and treated wastewaters from a municipal solid waste incineration bottom ash recycling facility. The 50%-diluted, untreated wastewater exhibited acute toxicity (plants died within 24 hours). Highly diluted doses (3 and 6%) of both wastewater types displayed no significant differences when compared with the control. Treating the wastewater through sequential physical filtration and chemical precipitation processes decreased not only the dissolved solids content but also the pH and salt content. In addition, significant accumulations of Sr, Cr, and Sn were observed in the hydroponically grown I. aquatica plant tissues; in particular, the bioaccumulation of Sr in the leaves and roots was unexpectedly high.

  7. Treatment of leachate from MSWI bottom ash landfilling with anaerobic sulphate-reducing process.

    Science.gov (United States)

    Sivula, Leena J; Väisänen, Ari O; Rintala, Jukka A

    2007-02-01

    Removal of sulphate and toxic elements from the leachate of a field landfill lysimeter (112m(3)), containing municipal solid waste incineration (MSWI) bottom ash, was studied. The leachate was treated in two parallel laboratory upflow anaerobic sludge blanket (UASB) reactors without and with ethanol as additional carbon source. With ethanol more than 65% of sulphate was removed, while without ethanol removal was negligible. The treatment removed Ba, Ca, Cu, Mn, Mo, Ni, Pb, Tl, Sb, Se, Sr, and Zn of the studied 35 trace and other elements. The sequential extraction of the reactor sludge at the end of runs confirmed that with a few exceptions (Ba, Ca, and Cu) the main mechanism by which the elements were removed was precipitation as sulphides.

  8. Life cycle assessment of resource recovery from municipal solid waste incineration bottom ash.

    Science.gov (United States)

    Allegrini, Elisa; Vadenbo, Carl; Boldrin, Alessio; Astrup, Thomas Fruergaard

    2015-03-15

    Bottom ash, the main solid output from municipal solid waste incineration (MSWI), has significant potential for the recovery of resources such as scrap metals and aggregates. The utilisation of these resources ideally enables natural resources to be saved. However, the quality of the recovered scrap metals may limit recycling potential, and the utilisation of aggregates may cause the release of toxic substances into the natural environment through leaching. A life cycle assessment (LCA) was applied to a full-scale MSWI bottom ash management and recovery system to identify environmental breakeven points beyond which the burdens of the recovery processes outweigh the environmental benefits from valorising metals and mineral aggregates. Experimental data for the quantity and quality of individual material fractions were used as a basis for LCA modelling. For the aggregates, three disposal routes were compared: landfilling, road sub-base and aggregate in concrete, while specific leaching data were used as the basis for evaluating toxic impacts. The recovery and recycling of aluminium, ferrous, stainless steel and copper scrap were considered, and the importance of aluminium scrap quality, choice of marginal energy technologies and substitution rates between primary and secondary aluminium, stainless steel and ferrous products, were assessed and discussed. The modelling resulted in burdens to toxic impacts associated with metal recycling and leaching from aggregates during utilisation, while large savings were obtained in terms of non-toxic impacts. However, by varying the substitution rate for aluminium recycling between 0.35 and 0.05 (on the basis of aluminium scrap and secondary aluminium alloy market value), it was found that the current recovery system might reach a breakeven point between the benefits of recycling and energy expended on sorting and upgrading the scrap.

  9. Speciation of Cu in MSWI bottom ash and its relation to Cu leaching

    Energy Technology Data Exchange (ETDEWEB)

    Arickx, S. [Department of Chemical Engineering, Katholieke Universiteit Leuven, W. de Croylaan 46, B-3001 Leuven (Belgium)], E-mail: stefanie.arickx@telenet.be; Gerven, T. van [Department of Chemical Engineering, Katholieke Universiteit Leuven, W. de Croylaan 46, B-3001 Leuven (Belgium); Boydens, E.; L' Hoest, P.; Blanpain, B. [Department of Metallurgy and Materials Engineering, Katholieke Universiteit Leuven, Kasteelpark Arenberg 44, B-3001 Leuven (Belgium); Vandecasteele, C. [Department of Chemical Engineering, Katholieke Universiteit Leuven, W. de Croylaan 46, B-3001 Leuven (Belgium)], E-mail: carlo.vandecasteele@cit.kuleuven.be

    2008-12-15

    In Flanders, recycling of bottom ash is mainly inhibited by the high leaching of Cu. Although it has been proved that dissolved organic C plays a major role in the Cu leaching, the possible role of inorganic Cu mineral speciation has never been experimentally examined. In this study the speciation of Cu is investigated using a combination of optical microscopy and electron microprobe -WDX/EDX. Several Cu species were determined. Metallic Cu (with or without an oxide shell), CuO and Cu{sub 2}O were the most abundant. These particles were most likely present in wire-like structures. Copper also occurred as alloy (brass, bronze, zamak), and was found frequently together with typical elements such as Ca, Cl and S. Finally, small metallic Cu particles seemed to be trapped in or precipitated on oxides and silicates. Based on this Cu speciation study, pure Cu minerals were selected and leached as a function of time. The solubility after equilibrium of all studied Cu minerals never exceeded 20 {mu}g/L (which equals 10% of the total Cu leaching). The effect of heating (2 h at 400 deg. C) on the speciation of Cu was investigated using the same combination of techniques. Results show that metallic Cu seemed to be converted to Cu oxide (mostly CuO) and that the particles were more porous after heating. These conclusions were verified by XRD analysis of the heated pure Cu minerals. After heating, the Cu minerals were also leached as a function of time, to study the impact on Cu leaching. Results indicate that their leaching had slightly increased in comparison with the non-heated Cu minerals. However, the major decrease in Cu leaching in heated bottom ash, more than neutralizes this effect and thus can be attributed to the destruction of organic matter and not to the (small) change in Cu speciation.

  10. Use of bottom ash from thermal power plant and lime as filler in bituminous mixtures

    Directory of Open Access Journals (Sweden)

    López-López, E.

    2015-06-01

    Full Text Available This study focuses on the characterization of bottom ash (PCC-BA and determining the mechanical characteristics of hot mix asphalt (HMA using PCC-BA and hydrated lime (HL as filler. Physical and chemical characterization of the bottom ash was carried out to evaluate its eventual reutilization as filler substitute. The materials tested in this study were made using 0%, 25%, 50%, 70% and 100% of PCC-BA combined with HL. HMA mixes were evaluated in terms of their engineering properties, namely: air voids in the mixes, water sensitivity, stiffness modulus, performance in wheel tracking test and fatigue resistance. The results obtained indicate that HMA mixes with a filler blend of 70% PCC-BA and 30% HL fulfil European standards and are suitable for light traffic or small infrastructures.Este estudio se centra en la caracterización de las cenizas de fondo (PCC-BA y la determinación de las características mecánicas de mezclas bituminosas en caliente (HMA, utilizando cenizas de fondo y la cal hidratada (HL como filler. Se realizó la caracterización física y química de las cenizas de fondo para evaluar su empleo como sustituto de filler. Las mezclas ensayadas en este estudio se realizaron utilizando 0%, 25%, 50%, 70% y 100% de cenizas de fondo combinadas con cal hidratada. Se evaluaron propiedades ingenieriles de las mezclas bituminosas, tales como los huecos de aire en las mezclas, la sensibilidad al agua, el módulo de rigidez, el ensayo de pista y la resistencia a la fatiga. Los resultados obtenidos indican que las mezclas bituminosas fabricadas con una combinación de filler del 70% de cenizas de fondo y el 30% cal hidratada, cumplen con las normas europeas y son adecuados para su aplicación con tráficos ligeros o en pequeñas infraestructuras.

  11. Corporate Health and Wellness and the Financial Bottom Line

    Science.gov (United States)

    Conradie, Christina Susanna; van der Merwe Smit, Eon; Malan, Daniel Pieter

    2016-01-01

    Objective: The research objective was to test the hypothesis that corporate health and wellness contributed positively to South African companies’ financial results. Methods: The past share market performance of eligible healthy companies, based on Discovery's Healthy Company Index, was tracked under three investment scenarios and compared with the market performance on the basis of the JSE FTSE All Share Index. Results: The evidence supports the hypothesis that a culture of health and wellness provides a financial advantage, in so far as the portfolio of healthy companies consistently outperformed the market over the selected simulations. Conclusions: Given the limitations of the investigation, namely small sample size, the brevity of the period of investigation, and the reliance on accessibility sampling, the research provides the first and preliminary evidence supportive of the direct financial benefits of companies’ wellness programs. PMID:26849271

  12. Hydrothermal solidification of municipal solid waste incineration bottom ash with slag addition.

    Science.gov (United States)

    Jing, Zhenzi; Ran, Xianqiang; Jin, Fangming; Ishida, Emile H

    2010-01-01

    Hydrothermal solidification of municipal solid waste incineration (MSWI) bottom ash has been carried out under saturated steam pressure (1.56 MPa) at 200 degrees C for up to 24 h by mixing quartz, slaked lime and water-cooled blast furnace slag (WBFS). The strength enhancement for the WBFS addition was best. The strength development was shown to be due mainly to tobermorite formation, and the tobermorite formation densified matrix, thus promoting the strength development. WBFS seemed to have a higher reactivity than the quartz during the initial hydrothermal process, which provided more silica available to harden the solidified specimens. However, a longer curing time (24 h) was favorable to the quartz dissolution for tobermorite formation, which in turn, enhanced the strength for quartz addition. Curing time affected the crystal morphology evolution, and the stubby plate of tobermorite seemed to result in a high strength enhancement in this study. Laboratory leaching tests were conducted to determine the amount of heavy metals dissolved from the final solidified specimens, and the leaching results showed that after hydrothermal processing the heavy metals dissolved from the solidified specimens were reduced effectively. As such, the hydrothermal processing may have a high potential for recycling/reusing MSWI ash on a large scale.

  13. Strength properties of concrete incorporating coal bottom ash and granulated blast furnace slag.

    Science.gov (United States)

    Ozkan, Omer; Yüksel, Isa; Muratoğlu, Ozgür

    2007-01-01

    Coal bottom ash (CBA) and fly ash (FA) are by-products of thermal power plants. Granulated blast-furnace slag (GBFS) is developed during iron production in iron and steel plants. This research was conducted to evaluate the compressive strength property and some durability characteristics of concrete incorporating FA, CBA, and GBFS. FA is used as an effective partial cement replacement; CBA and GBFS are used as partial replacement for fine aggregate without grinding. Water absorption capacity, unit weight and compressive strengths in 7, 28, and 90-day ages were assessed experimentally. For these experiments, concrete specimens were produced in the laboratory in appropriate shapes. The samples are divided into two main categories: M1, which incorporated CBA and GBFS; and M2, which incorporated FA, CBA, and GBFS. Remarkable decreases are observed in compressive strength and water absorption capacity of the concrete; bulk density of the concrete is also decreased. It can be concluded that if the content of CBA and GBFS is limited to a reasonable amount, the small decreases in strength can be accepted for low strength concrete works.

  14. Synthesis of thermostable geopolymer from circulating fluidized bed combustion (CFBC) bottom ashes.

    Science.gov (United States)

    Xu, Hui; Li, Qin; Shen, Lifeng; Wang, Wei; Zhai, Jianping

    2010-03-15

    Circulating fluidized bed combustion (CFBC) bottom ashes (CBAs) are a class of calcined aluminosilicate wastes with a unique thermal history. While landfill disposal of hazardous element-containing CBAs poses serious challenge, these wastes have long been neglected as source materials for geopolymer production. In this paper, geopolymerization of ground CBAs was investigated. Reactivity of the CBAs was analyzed by respective dissolution of the ashes in 2, 5, and 10N NaOH and KOH solutions. Geopolymer pastes were prepared by activating the CBAs by a series of alkalis hydroxides and/or sodium silicate solutions. Samples were cured at 40 degrees C for 168 h, giving a highest compressive strength of 52.9 MPa. Of the optimal specimen, characterization was conducted by TG-DTA, SEM, XRD, as well as FTIR analyses, and thermal stability was determined in terms of compressive strength evolution via exposure to 800 or 1050 degrees C followed by three cooling regimes, i.e. cooling in air, cooling in the furnace, and immerging in water. The results show that CBAs could serve as favorable source materials for thermostable geopolymers, which hold a promise to replace ordinary Portland cement (OPC) and organic polymers in a variety of applications, especially where fire hazards are of great concern.

  15. Vitrified bottom ash slag from municipal solid waste incinerators - Phase relations of CaO-SiO2-Na20 oxide system

    NARCIS (Netherlands)

    Zhang, Z.; Xiao, Y.; Yang, Y.; Boom, R.; Voncken, J.H.L.

    2009-01-01

    Vitrification is considered to be an attractive technology for bottom ash treatment because it destroys the hazardous organics, contributes to immobilization of the heavy metals, and additionally it reduces drastically the volume. The main components of the vitrified bottom ash slag are SiO2 , CaO,

  16. Geochemical modelling and identification of leaching processes in MSWI bottom ash : implications for the short-term and long-term release of contaminants

    NARCIS (Netherlands)

    Meima, J.A.

    1997-01-01

    Municipal Solid Waste Incinerator (MSWI) bottom ash is the major residue that remains after the incineration of Municipal Solid Waste. The slag-like material is produced world-wide in very large and everincreasing quantities. In the past the bottom ash was usually disposed, nowadays it is increasing

  17. Vitrified bottom ash slag from municipal solid waste incinerators - Phase relations of CaO-SiO2-Na20 oxide system

    NARCIS (Netherlands)

    Zhang, Z.; Xiao, Y.; Yang, Y.; Boom, R.; Voncken, J.H.L.

    2009-01-01

    Vitrification is considered to be an attractive technology for bottom ash treatment because it destroys the hazardous organics, contributes to immobilization of the heavy metals, and additionally it reduces drastically the volume. The main components of the vitrified bottom ash slag are SiO2 , CaO,

  18. The leaching of major and trace elements from MSWI bottom ash as a function of pH and time

    NARCIS (Netherlands)

    Dijkstra, J.J.; Sloot, van der H.A.; Comans, R.N.J.

    2006-01-01

    In this paper, the leaching behaviour of major components (Al, Ca, SO4, Mg, Si, Fe, Na and DOC) and trace elements (Ni, Zn, Cd, Cu, Pb, Mo and Sb) from MSWI bottom ash is studied as a function of time over a wide range of pH, under pH-controlled conditions. Equilibrium geochemical modelling using th

  19. Use of bottom ash from olive pomace combustion in the production of eco-friendly fired clay bricks.

    Science.gov (United States)

    Eliche-Quesada, D; Leite-Costa, J

    2016-02-01

    Olive pomace bottom ash was used to replace different amounts (10-50wt%) of clay in brick manufacturing. The aim of this study is both studying bricks properties and showing a new way of olive pomace bottom ash recycling. Properties of waste bricks were compared to conventional products following standard procedures in order to determine the maximum waste percentage. The amount of olive pomace bottom ash is limited to 20wt%, obtaining bricks with superior engineering properties when 10wt% of waste is added. Adding higher amount of waste (30-50wt%) resulted in bricks with water absorption and compressive strength values on the edge of meeting those established by standards. Therefore, the addition of 10 and 20wt% of olive pomace bottom ash produced bricks with a bulk density of 1635 and 1527kg/m(3) and a compressive strength of 33.9MPa and 14.2MPa, respectively. Fired bricks fulfil standards requirements for clay masonry units, offering, at the same time, better thermal insulation of buildings due to a reduction in thermal conductivity of 14.4% and 16.8% respectively, compared to control bricks (only clay). Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Influence of Bottom Ash Replacements as Fine Aggregate on the Property of Cellular Concrete with Various Foam Contents

    Directory of Open Access Journals (Sweden)

    Patchara Onprom

    2015-01-01

    Full Text Available This research focuses on evaluating the feasibility of utilizing bottom ash from coal burning power plants as a fine aggregate in cellular concrete with various foam contents. Flows of all mixtures were controlled within 45 ± 5% and used foam content at 30%, 40%, 50%, 60%, and 70% by volume of mixture. Bottom ash from Mae Moh power plant in Thailand was used to replace river sand at the rates of 0%, 25%, 50%, 75%, and 100% by volume of sand. Compressive strength, water absorption, and density of cellular concretes were determined at the ages of 7, 14, and 28 days. Nonlinear regression technique was developed to construct the mathematical models for predicting the compressive strength, water absorption, and density of cellular concrete. The results revealed that the density of cellular concrete decreased while the water absorption increased with an increase in replacement level of bottom ash. From the experimental results, it can be concluded that bottom ash can be used as fine aggregate in the cellular concrete. In addition, the nonlinear regression models give very high degree of accuracy (R2>0.99.

  1. Mechanisms contributing to the thermal analysis of waste incineration bottom ash and quantification of idfferent carbon species

    NARCIS (Netherlands)

    Rocca, S.; Zomeren, van A.; Costa, G.; Dijkstra, J.J.; Comans, R.N.J.; Lombardi, F.

    2013-01-01

    The focus of this study was to identify the main compounds affecting the weight changes of bottom ash (BA) in conventional loss on ignition (LOI) tests and to obtain a better understanding of the individual processes in heterogeneous (waste) materials such as BA. Evaluations were performed on BA sam

  2. Full Scale Tests of Short-Term Municipal Solid Waste Incineration Bottom Ash Weathering Before Landfill Disposal

    Directory of Open Access Journals (Sweden)

    Franco Marchese

    2009-01-01

    Full Text Available Problem statement: Natural weathering is the most economic method of treatment in order to reduce the release of heavy metals present in the residue. Approach: The aim of the study was to optimize the minimum weathering times that were useful to reduce the lead release to within the Italian limits for landfill disposal. The mechanism of short-term weathering of MSWI bottom ash had been studied and its effect on the leaching of lead had been evaluated. Two bottom ash heaps had been realized for the experimental assessment: In one case an open-air situation was used, in the other, a heap placed under shelter was not exposed to rain. Results: The weathering course was monitored through the results of a leaching test that was carried out at different ageing times (EN 12457-2:2002. The total carbonates were also measured, at the same time, on the fine fraction of the weathered bottom ash (2 was fixed by air. The pH value was controlled by Portlandite dissolution only at the beginning, after the pH control seems to be due to aluminum hydroxides. Conclusion: The most significant changes in the bottom ash were found to occur in the first 60 days. It had been possible to verify the limited influence of washing phenomena while it was confirmed that carbonation was the most important process in short-term weathering and that it had an important rule on limiting lead release.

  3. The leaching of trace elements from municipal solid waste incinerator bottom ash at different stages of weathering

    NARCIS (Netherlands)

    Meima, J.A.; Comans, R.N.J.

    1999-01-01

    For a proper assessment of the environmental impact of the utilisation and disposal of Municipal Solid Waste Incinerator (MSWI) bottom ash it is necessary to understand weathering processes and their effects on (trace) element leaching. The authors have investigated the processes that control the le

  4. The leaching of trace elements from municipal solid waste incinerator bottom ash at different stages of weathering

    NARCIS (Netherlands)

    Meima, J.A.; Comans, R.N.J.

    1999-01-01

    For a proper assessment of the environmental impact of the utilisation and disposal of Municipal Solid Waste Incinerator (MSWI) bottom ash it is necessary to understand weathering processes and their effects on (trace) element leaching. The authors have investigated the processes that control the le

  5. Experimental investigation of the Rowe's dilatancy law on an atypical granular medium from a municipal solid waste incineration bottom ash

    Science.gov (United States)

    Becquart, Frédéric; Abriak, Nor Edine

    2013-06-01

    Municipal Solid Waste Incineration (MSWI) bottom ashes are irregular granular media because of their origin and are very heterogeneous with a large quantity of angular particles of different chemical species. MSWI bottom ash is a renewable granular resource alternative to the use of non-renewable standard granular materials. Beneficial use of these alternative granular materials mainly lies in road engineering. However, the studies about mechanical properties of such granular media still remain little developed, those being mainly based on empirical considerations. In this paper, a study of mechanical behaviour of a MSWI bottom ash under axisymmetric triaxial loadings conditions is presented. Samples are initially dense after Proctor compaction, are saturated and tested in drained conditions, under different effective confining pressures ranging from 100 to 600 kPa. The evolutions of volumetric strains show an initial contracting phase followed by a dilatancy phase, more pronounced when the confining pressure is low. The stresses ratios at the characteristic state and at the critical state appear in good agreement and with a null rate of volume variation. The angles of internal friction and dilatancy of the studied MSWI bottom ash are estimated and are similar to conventional granular materials used especially in road engineering. The dilatancy law of Rowe is well experimentally verified on this irregular recycled granular material.

  6. Evaluation and prediction of emissions from a road built with bottom ash from municipal solid waste incineration (MSWI).

    Science.gov (United States)

    Aberg, Annika; Kumpiene, Jurate; Ecke, Holger

    2006-02-15

    In autumn 2001, a full-scale test road was built with municipal solid waste incineration (MSWI) bottom ash at the Dåvamyran landfill, Umeå, Northern Sweden. Leachates were collected from asphalted sections with either bottom ash or gravel as filling material. In this research, 12 months of ash leachate sampling were evaluated with respect to emissions of contaminants such as trace metals and chlorides (Cl). The usefulness of regression models describing trace metal mobility from bottom ash was also tested as predictive tools for reusability applications of MSWI bottom ash. Cl, Cu, and Cr had the highest mobility (considering leachate concentrations) in the ash leachate, though concentrations of Cl and Cu decreased during the sampling period (Cl from 10,000 to 600 mg l(-1); Cu from 1600 to 500 microg l(-1)). An increased mobility of Cr during the autumns (about 3-4 times higher compared to the summer) was noted with a maximum value of nearly 70 microg l(-1) during autumn 2001. Pb showed a very low mobility over the entire year with leachate concentrations of around 3-4 microg l(-1). Chemical equilibrium calculations using Minteq indicated that several Cu minerals were oversaturated in the leachate, thus mineral precipitation could be responsible for declining amounts of Cu in the leachate. Adsorption to iron oxides was found to be a probable explanation for the low mobility of Pb. A reasonably good agreement between regression models and field values were achieved for Ni, Pb, Zn, and Cu, while the models for Cd and Cr were less promising. Even though a large part of the variation (R2=61-97%) in the leaching experiment could be explained by only pH and L/S, field data were much more scattered than expected from field pH.

  7. M(o)ssbauer spectroscopic studies the characterization of three China coal and the corresponding fly-ashes and bottom ashes

    Institute of Scientific and Technical Information of China (English)

    YAO Duo-xi; ZHI Xia-chen

    2006-01-01

    Three fresh China coals (lignitie, bituminite and anthracite) from different geological origin and the corresponding fly and bottom ashes were studied by room temperature(RT) M(o)ssbauer spectroscopy(MS). The iron-bearing minerals were characterized to was found in bituminite and anthracite coal.The M(o)ssbauer spectra of the fly and bottom ashes as a result of pulverised coal combustion(PCC) in Xiaolongtan,Shuicheng and Luohuang Power Plants are comprised of superimposed sextets and doulets of oxides includes maghemite(γ-Fe2O3), magnitite(Fe3O4), haematite(α-Fe2O3), magnesioferite (MgFe2O4), Fe3+/Fe2+-mullite, Fe3+-glass silicate andmetallic iron. The studies also show that iron-bearing minerals in coals are largely dependant on geological regions and coal rank, the composition of the corresponding fly and bottom ashes will not only depend on the type and mineralogy of the feed coal but also on the local nature of combustion.

  8. Development of a sintering process for recycling oil shale fly ash and municipal solid waste incineration bottom ash into glass ceramic composite

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhikun; Zhang, Lei; Li, Aimin, E-mail: leeam@dlut.edu.cn

    2015-04-15

    Highlights: • Glass ceramic composite is prepared from oil shale fly ash and MSWI bottom ash. • A novel method for the production of glass ceramic composite is presented. • It provides simple route and lower energy consumption in terms of recycling waste. • The vitrified slag can promote the sintering densification process of glass ceramic. • The performances of products decrease with the increase of oil shale fly ash content. - Abstract: Oil shale fly ash and municipal solid waste incineration bottom ash are industrial and municipal by-products that require further treatment before disposal to avoid polluting the environment. In the study, they were mixed and vitrified into the slag by the melt-quench process. The obtained vitrified slag was then mixed with various percentages of oil shale fly ash and converted into glass ceramic composites by the subsequent sintering process. Differential thermal analysis was used to study the thermal characteristics and determine the sintering temperatures. X-ray diffraction analysis was used to analyze the crystalline phase compositions. Sintering shrinkage, weight loss on ignition, density and compressive strength were tested to determine the optimum preparation condition and study the co-sintering mechanism of vitrified amorphous slag and oil shale fly ash. The results showed the product performances increased with the increase of sintering temperatures and the proportion of vitrified slag to oil shale fly ash. Glass ceramic composite (vitrified slag content of 80%, oil shale fly ash content of 20%, sintering temperature of 1000 °C and sintering time of 2 h) showed the properties of density of 1.92 ± 0.05 g/cm{sup 3}, weight loss on ignition of 6.14 ± 0.18%, sintering shrinkage of 22.06 ± 0.6% and compressive strength of 67 ± 14 MPa. The results indicated that it was a comparable waste-based material compared to previous researches. In particular, the energy consumption in the production process was reduced

  9. Arsenic remediation of drinking water using iron-oxide coated coal bottom ash

    Energy Technology Data Exchange (ETDEWEB)

    MATHIEU, JOHANNA L.; GADGIL, ASHOK J.; ADDY, SUSAN E.A.; KOWOLIK, KRISTIN

    2010-06-01

    We describe laboratory and field results of a novel arsenic removal adsorbent called 'Arsenic Removal Using Bottom Ash' (ARUBA). ARUBA is prepared by coating particles of coal bottom ash, a waste material from coal fired power plants, with iron (hydr)oxide. The coating process is simple and conducted at room temperature and atmospheric pressure. Material costs for ARUBA are estimated to be low (~;;$0.08 per kg) and arsenic remediation with ARUBA has the potential to be affordable to resource-constrained communities. ARUBA is used for removing arsenic via a dispersal-and-removal process, and we envision that ARUBA would be used in community-scale water treatment centers. We show that ARUBA is able to reduce arsenic concentrations in contaminated Bangladesh groundwater to below the Bangladesh standard of 50 ppb. Using the Langmuir isotherm (R2 = 0.77) ARUBA's adsorption capacity in treating real groundwater is 2.6x10-6 mol/g (0.20 mg/g). Time-to-90percent (defined as the time interval for ARUBA to remove 90percent of the total amount of arsenic that is removed at equilibrium) is less than one hour. Reaction rates (pseudo-second-order kinetic model, R2>_ 0.99) increase from 2.4x105 to 7.2x105 g mol-1 min-1 as the groundwater arsenic concentration decreases from 560 to 170 ppb. We show that ARUBA's arsenic adsorption density (AAD), defined as the milligrams of arsenic removed at equilibrium per gram of ARUBA added, is linearly dependent on the initial arsenic concentration of the groundwater sample, for initial arsenic concentrations of up to 1600 ppb and an ARUBA dose of 4.0 g/L. This makes it easy to determine the amount of ARUBA required to treat a groundwater source when its arsenic concentration is known and less than 1600 ppb. Storing contaminated groundwater for two to three days before treatment is seen to significantly increase ARUBA's AAD. ARUBA can be separated from treated water by coagulation and clarification, which is expected to

  10. Alteration of municipal solid waste incineration bottom ash focusing on the evolution of iron-rich constituents.

    Science.gov (United States)

    Wei, Yunmei; Shimaoka, Takayuki; Saffarzadeh, Amirhomayoun; Takahashi, Fumitake

    2011-01-01

    Municipal solid waste incineration (MSWI) bottom ash contains a considerable amount of Fe-rich constituents. The behaviors of these constituents, such as dissolution and precipitation, are quite important as they regulate the distribution of a series of ions between the liquid (percolated fluid) and solid (ash deposit) phases. This paper studied both fresh and weathered MSWI bottom ash from the mineralogical and geochemical viewpoint by utilizing optical microscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX), and powder X-ray diffraction. The analysis results revealed that for the fresh bottom ash, iron preferentially existed in the chemical forms of spinel group (mainly Fe(3)O(4), and a series of Al- or Ti- substituted varieties), metallic inclusions (including Fe-P, Fe-S, Fe-Cu-Pb), hematite (Fe(2)O(3)) and unburned iron pieces. In the 1-20 years weathered bottom ash collected from a landfill site, interconversions among these Fe-rich constituents were identified. Consequently, numerous secondary products were developed, including goethite (α-FeOOH), lepidocrocite (γ-FeOOH), hematite, magnetite, wustite (FeO), Fe-Si-rich gel phase. Of all these transformation products, hydrous iron oxides were the most common secondary minerals. Quantitative chemical analysis of these secondary products by SEM/EDX disclosed a strong association between the newly formed hydrous iron oxides and heavy metals (e.g. Pb, Zn, Ni, and Cu). The results of this study suggest that the processes of natural weathering and secondary mineralization contribute to reduction of the potential risks of heavy metals to the surrounding environments. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Effect of Mass Proportion of Municipal Solid Waste Incinerator Bottom Ash Layer to Municipal Solid Waste Layer on the Cu and Zn Discharge from Landfill.

    Science.gov (United States)

    Kong, Qingna; Yao, Jun; Qiu, Zhanhong; Shen, Dongsheng

    2016-01-01

    Municipal solid waste incinerator (MSWI) bottom ash is often used as the protection layer for the geomembrane and intermediate layer in the landfill. In this study, three sets of simulated landfills with different mass proportion of MSWI bottom ash layer to municipal solid waste (MSW) layer were operated. Cu and Zn concentrations in the leachates and MSW were monitored to investigate the effect of MSWI bottom ash layer on the Cu and Zn discharge from the landfill. The results showed that the Zn discharge was dependent on the mass proportion of MSWI bottom ash layer. The pH of landfill was not notably increased when the mass proportion of MSWI bottom ash layer to MSW layer was 1 : 9, resulting in the enhancement of the Zn discharge. However, Zn discharge was mitigated when the mass proportion was 2 : 8, as the pH of landfill was notably promoted. The discharge of Cu was not dependent on the mass proportion, due to the great affinity of Cu to organic matter. Moreover, Cu and Zn contents of the sub-MSW layer increased due to the MSWI bottom ash layer. Therefore, the MSWI bottom ash layer can increase the potential environmental threat of the landfill.

  12. Effect of Mass Proportion of Municipal Solid Waste Incinerator Bottom Ash Layer to Municipal Solid Waste Layer on the Cu and Zn Discharge from Landfill

    Directory of Open Access Journals (Sweden)

    Qingna Kong

    2016-01-01

    Full Text Available Municipal solid waste incinerator (MSWI bottom ash is often used as the protection layer for the geomembrane and intermediate layer in the landfill. In this study, three sets of simulated landfills with different mass proportion of MSWI bottom ash layer to municipal solid waste (MSW layer were operated. Cu and Zn concentrations in the leachates and MSW were monitored to investigate the effect of MSWI bottom ash layer on the Cu and Zn discharge from the landfill. The results showed that the Zn discharge was dependent on the mass proportion of MSWI bottom ash layer. The pH of landfill was not notably increased when the mass proportion of MSWI bottom ash layer to MSW layer was 1 : 9, resulting in the enhancement of the Zn discharge. However, Zn discharge was mitigated when the mass proportion was 2 : 8, as the pH of landfill was notably promoted. The discharge of Cu was not dependent on the mass proportion, due to the great affinity of Cu to organic matter. Moreover, Cu and Zn contents of the sub-MSW layer increased due to the MSWI bottom ash layer. Therefore, the MSWI bottom ash layer can increase the potential environmental threat of the landfill.

  13. Innovative treatment trains of bottom ash (BA) from municipal solid waste incineration (MSWI) in Germany.

    Science.gov (United States)

    Holm, Olaf; Simon, Franz-Georg

    2017-01-01

    The industrial sector of bottom ash (BA) treatment from municipal solid waste incineration (MSWI) in Germany is currently changing. In order to increase the recovery rates of metals or to achieve a higher quality of mineral aggregates derived from BA, new procedures have been either implemented to existing plants or completely new treatment plants have been built recently. Three treatment trains, which are designated as entire sequences of selected processing techniques of BA, are introduced and compared. One treatment train is mainly characterized by usage of a high speed rotation accelerator whereas another is operating completely without crushing. In the third treatment train the BA is processed wet directly after incineration. The consequences for recovered metal fractions and the constitution of remaining mineral aggregates are discussed in the context of legislative and economical frameworks. Today the recycling or disposal options of mineral residues still have a high influence on the configuration and the operation mode of the treatment trains of BA despite of the high value of recovered metals.

  14. Characterization of MSWI bottom ashes towards utilization as glass raw material.

    Science.gov (United States)

    Monteiro, R C C; Figueiredo, C F; Alendouro, M S; Ferro, M C; Davim, E J R; Fernandes, M H V

    2008-01-01

    The characterization of the bottom ashes produced by two Portuguese municipal solid waste incinerators (MSWI) was performed with the aim of assessing the feasibility of using this waste as raw material in the production of glass that can be further processed as glass-ceramics for application in construction. Density and particle size distribution measurements were carried out for physical characterization. Chemical characterization revealed that SiO(2), a network glass former oxide, was present in a relatively high content (52-58wt%), indicating the suitability for this waste to be employed in the development of vitreous materials. CaO, Na(2)O and K(2)O, which act as fluxing agents, were present in various amounts (2-17wt%) together with several other oxides normally present in ceramic and glass raw materials. Mineralogical characterization revealed that the main crystalline phases were quartz (SiO(2)) and calcite (CaCO(3)) and that minor amounts of different alkaline and alkaline-earth aluminosilicate phases were also present. Thermal characterization showed that the decomposition of the different compounds occurred up to 1100 degrees C and that total weight loss was ceramics to be applied in construction.

  15. Production of pyroxene ceramics from the fine fraction of incinerator bottom ash.

    Science.gov (United States)

    Bourtsalas, A; Vandeperre, L J; Grimes, S M; Themelis, N; Cheeseman, C R

    2015-11-01

    Incinerator bottom ash (IBA) is normally processed to extract metals and the coarse mineral fraction is used as secondary aggregate. This leaves significant quantities of fine material, typically less than 4mm, that is problematic as reuse options are limited. This work demonstrates that fine IBA can be mixed with glass and transformed by milling, calcining, pressing and sintering into high density ceramics. The addition of glass aids liquid phase sintering, milling increases sintering reactivity and calcining reduces volatile loss during firing. Calcining also changes the crystalline phases present from quartz (SiO2), calcite (CaCO3), gehlenite (Ca2Al2SiO7) and hematite (Fe2O3) to diopside (CaMgSi2O6), clinoenstatite (MgSiO3) and andradite (Ca3Fe2Si3O12). Calcined powders fired at 1080°C have high green density, low shrinkage (ceramics that have negligible water absorption. The transformation of the problematic fraction of IBA into a raw material suitable for the manufacture of ceramic tiles for use in urban paving and other applications is demonstrated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Geopolymers with a high percentage of bottom ash for solidification/immobilization of different toxic metals.

    Science.gov (United States)

    Boca Santa, Rozineide A Antunes; Soares, Cíntia; Riella, Humberto Gracher

    2016-11-15

    Geopolymers are produced using alkali-activated aluminosilicates, either as waste or natural material obtained from various sources. This study synthesized geopolymers from bottom ash and metakaolin (BA/M) in a 2:1wt ratio to test the solidification/immobilization (S/I) properties of heavy metals in geopolymer matrices, since there is very little research using BA in this type of matrices. Therefore, a decision was made to use more than 65% of BA in geopolymer synthesis with and without the addition of heavy metals. The S/I tests with metals used 10, 15 and 30ml of a waste solution after pickling of printed circuit boards containing metals, including Pb, Cr, Cu, Fe, Sn, As and Ni, in different proportions. As alkali activator, the NaOH and KOH were used in the concentrations of 8 and 12M in the composition of Na2SiO3 in 1:2vol ratios. To test S/I efficiency, tests were conducted to obtain the leached and solubilized extract. The analysis was carried out through X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Scanning Electron Microscope (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS) and compressive strength tests. The geopolymer showed a high degree of S/I of the metals; in some samples, the results reached nearly 100%.

  17. Distribution and mode of occurrence of uranium in bottom ash derived from high-germanium coals.

    Science.gov (United States)

    Sun, Yinglong; Qi, Guangxia; Lei, Xuefei; Xu, Hui; Li, Lei; Yuan, Chao; Wang, Yi

    2016-05-01

    The radioactivity of uranium in radioactive coal bottom ash (CBA) may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride (HF) leaching, Siroquant (Rietveld) quantification, magnetic separation, and electron probe microanalysis (EPMA). The Tessier sequential extraction showed that the uranium in the residual and Fe-Mn oxide fractions was dominant (59.1% and 34.9%, respectively). The former was mainly incorporated into aluminosilicates, retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite (Fe3O4) and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment.

  18. Coal bottom ash and pine wood peelings as root substrates in a circulating nutriculture system

    Energy Technology Data Exchange (ETDEWEB)

    Woodard, M.A.; Bearce, B.C.; Cluskey, S.; Townsend, E. (West Virginia University, Morgantown, WV (USA). Division of Plant and Soil Science)

    1993-06-01

    'Inca Yellow' marigolds ([ital Tagetes erecta L.]) were planted in polyethylene bags containing coal bottom ash (CBA), pine wood peelings (PWP), a mixture of 1 CBA: 1 PWP (v/v), and loose Grodan Rockwool (RW) and grown in a circulating nutriculture system. Three fertigation frequencies of 12,6, or 4 cycles per 12-hour light period were set with a duration of 5 minutes each. Flower diameters of marigolds grown in CBA, PWP, and CBA-PWP exceeded flower diameters of RW-grown marigolds, and days from planting to harvest were less in CBA and CBA-PWP than in the other two media. There was no interaction between medium and fertigation frequency. Foliar analysis showed no significant differences in plant elemental composition among root media or fertigation frequencies. Postharvest PWP water extracts contained higher P levels than extracts of other media, and CBA-PWP water extracts contained higher K, Ca, and Mg. In the CBA-PWP mixture, decomposition products from PWP may have increased P solubility and solubilized the K, Ca, and Mg in CBA.

  19. Impact of MSWI Bottom Ash Codisposed with MSW on Landfill Stabilization with Different Operational Modes

    Directory of Open Access Journals (Sweden)

    Wen-Bing Li

    2014-01-01

    Full Text Available The aim of the study was to investigate the impact of municipal solid waste incinerator (MSWI bottom ash (BA codisposed with municipal solid waste (MSW on landfill stabilization according to the leachate quality in terms of organic matter and nitrogen contents. Six simulated landfills, that is, three conventional and three recirculated, were employed with different ratios of MSWI BA to MSW. The results depicted that, after 275-day operation, the ratio of MSWI BA to fresh refuse of 1 : 10 (V : V in the landfill was still not enough to provide sufficient acid-neutralizing capacity for a high organic matter composition of MSW over 45.5% (w/w, while the ratio of MSWI BA to fresh refuse of 1 : 5 (V : V could act on it. Among the six experimental landfills, leachate quality only was improved in the landfill operated with the BA addition (the ratio of MSWI BA to fresh refuse of 1 : 5 (V : V and leachate recirculation.

  20. Impact of MSWI bottom ash codisposed with MSW on landfill stabilization with different operational modes.

    Science.gov (United States)

    Li, Wen-Bing; Yao, Jun; Malik, Zaffar; Zhou, Gen-Di; Dong, Ming; Shen, Dong-Sheng

    2014-01-01

    The aim of the study was to investigate the impact of municipal solid waste incinerator (MSWI) bottom ash (BA) codisposed with municipal solid waste (MSW) on landfill stabilization according to the leachate quality in terms of organic matter and nitrogen contents. Six simulated landfills, that is, three conventional and three recirculated, were employed with different ratios of MSWI BA to MSW. The results depicted that, after 275-day operation, the ratio of MSWI BA to fresh refuse of 1 : 10 (V : V) in the landfill was still not enough to provide sufficient acid-neutralizing capacity for a high organic matter composition of MSW over 45.5% (w/w), while the ratio of MSWI BA to fresh refuse of 1 : 5 (V : V) could act on it. Among the six experimental landfills, leachate quality only was improved in the landfill operated with the BA addition (the ratio of MSWI BA to fresh refuse of 1 : 5 (V : V)) and leachate recirculation.

  1. Use of municipal solid waste incineration bottom ashes in alkali-activated materials, ceramics and granular applications: A review.

    Science.gov (United States)

    Silva, R V; de Brito, J; Lynn, C J; Dhir, R K

    2017-06-29

    This paper presents a literature review on the incorporation of municipal solid waste incinerated bottom ash as raw material in several markets, other than those where it is conventionally used, such as geotechnical applications and road pavement construction. The main findings of an ample selection of experimental investigations on the use of the bottom ash as precursor of alkali-activated materials, as an adsorbent material for the removal of hazardous elements from wastewater and landfill gases, as soil replacement in agricultural activities, as partial or complete substitute of raw materials for the manufacture of ceramic-based products, as landfill cover and as biogas production enhancer, were gathered, collated and analysed. Copyright © 2017. Published by Elsevier Ltd.

  2. Improved electrical efficiency and bottom ash quality on waste combustion plants. Appendix A7 to A10

    Energy Technology Data Exchange (ETDEWEB)

    Hyks, J.; Astrup, T.; Jensen, Peter A.; Nesterov, I.; Boejer, M.; Frandsen, F.; Dam-Johansen, K.; Hedegaard Madsen, O.; Lundtorp, K. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Mogensen, Erhardt (Babcock and Wilcox Voelund A/S, Glostrup (Denmark))

    2010-07-01

    Investigations making it possible to evaluate and further develop concepts to improve electrical efficiency in a waste combustion plant were performed. Furthermore, one objective of the study was to investigate the possibilities of improving waste bottom ash leaching properties by use of a rotary kiln treatment. The project work included construction of a bench-scale rotary kiln, performing ash rotary kiln treatment experiments, conducting gas suction probe measurements on a waste incineration plant and making some concept evaluations. The influence of the rotary kiln thermal treatment on the leaching of Ca, Al, Si, Mg, Ba, Sr, Cl, Cu, Pb, Zn, Cr, Mo, sulfate, DOC and carbonate was determined. As a result of these tests, the rotary kiln thermal treatment of bottom ashes can be recommended for reducing the leaching of Cu, Pb, Cl, Zn and DOC; however, an increased leaching of Cr and Mo should be expected. The combustion conditions above the grate of a waste incineration plant were investigated and the release and concentration of volatile ash species in the flue gas such as Cl, Na, K, Ca, Pb, Zn and S were measured. The conducted measurements show that flue gas from grate sections 3 and 4 can produce a sufficiently hot flue gas that contains only low concentrations of corrosive species, and therefore can be used to increase superheater temperatures. Implementation of the so-called flue gas split concept together with other steam circle modifications on a waste combustion plant, and using a reasonable increase in final steam temperature from 400 to 500 deg. C, have the potential to increase electrical efficiency from 24 to 30% (with respect to lower fuel heating value) in a waste combustion plant. The appendices deal with the influence of kiln treatment on incineration bottom ash leaching; the influence of kiln treatment on corrosive species in deposits; operational strategy for rotary kiln; alkali/chloride release during refuse incineration on a grate. (Author)

  3. Improved electrical efficiency and bottom ash quality on waste combustion plants. Appendix A1 to A3

    Energy Technology Data Exchange (ETDEWEB)

    Nesterov, I.; Jensen, Peter A.; Dam-Johansen, K.; Kloeft, H.; Boejer, M. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Mogensen, Erhardt (Babcock and Wilcox Voelund A/S, Esbjerg (Denmark))

    2010-07-01

    Investigations making it possible to evaluate and further develop concepts to improve electrical efficiency in a waste combustion plant were performed. Furthermore, one objective of the study was to investigate the possibilities of improving waste bottom ash leaching properties by use of a rotary kiln treatment. The project work included construction of a bench-scale rotary kiln, performing ash rotary kiln treatment experiments, conducting gas suction probe measurements on a waste incineration plant and making some concept evaluations. The influence of the rotary kiln thermal treatment on the leaching of Ca, Al, Si, Mg, Ba, Sr, Cl, Cu, Pb, Zn, Cr, Mo, sulfate, DOC and carbonate was determined. As a result of these tests, the rotary kiln thermal treatment of bottom ashes can be recommended for reducing the leaching of Cu, Pb, Cl, Zn and DOC; however, an increased leaching of Cr and Mo should be expected. The combustion conditions above the grate of a waste incineration plant were investigated and the release and concentration of volatile ash species in the flue gas such as Cl, Na, K, Ca, Pb, Zn and S were measured. The conducted measurements show that flue gas from grate sections 3 and 4 can produce a sufficiently hot flue gas that contains only low concentrations of corrosive species, and therefore can be used to increase superheater temperatures. Implementation of the so-called flue gas split concept together with other steam circle modifications on a waste combustion plant, and using a reasonable increase in final steam temperature from 400 to 500 deg. C, have the potential to increase electrical efficiency from 24 to 30% (with respect to lower fuel heating value) in a waste combustion plant. The appendices deal with incineration bottom ash leaching properties; design and construction of rotary kiln facility; manual to rotary kiln experiments. (Author)

  4. Improved electrical efficiency and bottom ash quality on waste combustion plants. Appendix A4 to A6

    Energy Technology Data Exchange (ETDEWEB)

    Kloeft, H.; Jensen, Peter A.; Nesterov, I.; Hyks, J.; Astrup, T. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Mogensen, Erhardt (Babcock and Wilcox Voelund A/S, Glostrup (Denmark))

    2010-07-01

    Investigations making it possible to evaluate and further develop concepts to improve electrical efficiency in a waste combustion plant were performed. Furthermore, one objective of the study was to investigate the possibilities of improving waste bottom ash leaching properties by use of a rotary kiln treatment. The project work included construction of a bench-scale rotary kiln, performing ash rotary kiln treatment experiments, conducting gas suction probe measurements on a waste incineration plant and making some concept evaluations. The influence of the rotary kiln thermal treatment on the leaching of Ca, Al, Si, Mg, Ba, Sr, Cl, Cu, Pb, Zn, Cr, Mo, sulfate, DOC and carbonate was determined. As a result of these tests, the rotary kiln thermal treatment of bottom ashes can be recommended for reducing the leaching of Cu, Pb, Cl, Zn and DOC; however, an increased leaching of Cr and Mo should be expected. The combustion conditions above the grate of a waste incineration plant were investigated and the release and concentration of volatile ash species in the flue gas such as Cl, Na, K, Ca, Pb, Zn and S were measured. The conducted measurements show that flue gas from grate sections 3 and 4 can produce a sufficiently hot flue gas that contains only low concentrations of corrosive species, and therefore can be used to increase superheater temperatures. Implementation of the so-called flue gas split concept together with other steam circle modifications on a waste combustion plant, and using a reasonable increase in final steam temperature from 400 to 500 deg. C, have the potential to increase electrical efficiency from 24 to 30% (with respect to lower fuel heating value) in a waste combustion plant. The appendices deal with collection of slags for the rotary kiln experiments; overview of the thermal treatment experiments - phase 1; a journal paper with the title ''Quantification of leaching from waste incineration bottom ash treated in a rotary kiln

  5. Geotechnical properties of MSW-incinerated bottom ash%垃圾焚烧炉渣的土工特性

    Institute of Scientific and Technical Information of China (English)

    许四法; 杨杨; 王哲

    2011-01-01

    To solve the problem of incinerator residue disposal and recycle, the changes of geotechnical properties of the bottom ash with time were investigated by indoor physical tests and SEM.The results show that the initial particle size is large when its diameter increases and the maximum dry density decreases with the time; that the bottom ash is in high initial void ratio and compressibility, but because of the adsorption and the hydrated reaction, the void ratio deceases with the time; and that the compressive strength increases and the deformation decreases with the time.Finally, the causes of the change on the geotechnical characteristics of the bottom ash with the time were analyzed by the electron microscopy,which provids a reference for efficacious utilization of bottom ash.%为了有效处理和利用炉渣,以炉渣为研究对象,采用室内物理试验和扫描电镜,探讨炉渣的性质随时间变化的特性.试验结果表明:随着放置时间的增加、粗颗粒变多以及最大干密度变小,炉渣的初始孔隙比较大,属于中高压缩性土,但由于吸附和水化反应,孔隙比随时间减小;同样,无侧限抗压强度随时间增加,变形下降.最后,通过电子显微镜分析了炉渣的土工特性随时间变化的原因,为炉渣的有效利用提供参考.

  6. Mechanisms contributing to the thermal analysis of waste incineration bottom ash and quantification of different carbon species.

    Science.gov (United States)

    Rocca, Stefania; van Zomeren, André; Costa, Giulia; Dijkstra, Joris J; Comans, Rob N J; Lombardi, Francesco

    2013-02-01

    The focus of this study was to identify the main compounds affecting the weight changes of bottom ash (BA) in conventional loss on ignition (LOI) tests and to obtain a better understanding of the individual processes in heterogeneous (waste) materials such as BA. Evaluations were performed on BA samples from a refuse derived fuel incineration (RDF-I) plant and a hospital waste incineration (HW-I) plant using thermogravimetric analysis and subsequent mass spectrometry (TG-MS) analysis of the gaseous thermal decomposition products. Results of TG-MS analysis on RDF-I BA indicated that the LOI measured at 550°C was due to moisture evaporation and dehydration of Ca(OH)(2) and hydrocalumite. Results for the HW-I BA showed that LOI at 550°C was predominantly related to the elemental carbon (EC) content of the sample. Decomposition of CaCO(3) around 700°C was identified in both materials. In addition, we have identified reaction mechanisms that underestimate the EC and overestimate the CaCO(3) contents of the HW-I BA during TG-MS analyses. These types of artefacts are expected to occur also when conventional LOI methods are adopted, in particular for materials that contain CaO/Ca(OH)(2) in combination with EC and/or organic carbon, such as e.g. municipal solid waste incineration (MSWI) bottom and fly ashes. We suggest that the same mechanisms that we have found (i.e. in situ carbonation) can also occur during combustion of the waste in the incinerator (between 450 and 650°C) demonstrating that the presence of carbonate in bottom ash is not necessarily indicative for weathering. These results may also give direction to further optimization of waste incineration technologies with regard to stimulating in situ carbonation during incineration and subsequent potential improvement of the leaching behavior of bottom ash.

  7. Development of a sintering process for recycling oil shale fly ash and municipal solid waste incineration bottom ash into glass ceramic composite.

    Science.gov (United States)

    Zhang, Zhikun; Zhang, Lei; Li, Aimin

    2015-04-01

    Oil shale fly ash and municipal solid waste incineration bottom ash are industrial and municipal by-products that require further treatment before disposal to avoid polluting the environment. In the study, they were mixed and vitrified into the slag by the melt-quench process. The obtained vitrified slag was then mixed with various percentages of oil shale fly ash and converted into glass ceramic composites by the subsequent sintering process. Differential thermal analysis was used to study the thermal characteristics and determine the sintering temperatures. X-ray diffraction analysis was used to analyze the crystalline phase compositions. Sintering shrinkage, weight loss on ignition, density and compressive strength were tested to determine the optimum preparation condition and study the co-sintering mechanism of vitrified amorphous slag and oil shale fly ash. The results showed the product performances increased with the increase of sintering temperatures and the proportion of vitrified slag to oil shale fly ash. Glass ceramic composite (vitrified slag content of 80%, oil shale fly ash content of 20%, sintering temperature of 1000 °C and sintering time of 2h) showed the properties of density of 1.92 ± 0.05 g/cm(3), weight loss on ignition of 6.14 ± 0.18%, sintering shrinkage of 22.06 ± 0.6% and compressive strength of 67 ± 14 MPa. The results indicated that it was a comparable waste-based material compared to previous researches. In particular, the energy consumption in the production process was reduced compared to conventional vitrification and sintering method. Chemical resistance and heavy metals leaching results of glass ceramic composites further confirmed the possibility of its engineering applications.

  8. Potential usage of fly and bottom ash from thermal power plant ”Nikola Tesla” landfill, Serbia

    Directory of Open Access Journals (Sweden)

    Čudić Vladica V.

    2012-01-01

    Full Text Available In Serbia, the ash from power plants has long been labelled as hazardous waste. With the adoption of the appropriate legislation this ash became secondary raw material with the potential usage. In this paper an analysis of the fly and bottom ash composition, which are disposed of in the power plant “Nikola Tesla A” landfill, is presented. Thirty samples, divided into three sets, were analyzed for trace elements As, Ba, Be, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Ti, V and Zn. The first and second set of samples were taken at the depth of 0.0-0.6 m, from cassette III, at the place of waste discharge (set I and in the centre of the cassette (set II.The third set of samples was taken from the same cassette spot but at the different depth. The estimated variations in quality within individual sets, as well as the comparison between sets I and II, were done. The repeatability of results by the depth of cassette (set III was also analyzed. The mixture consisting of 79.4% limestone, 17% clay, 0.5% sand, 0.55% iron ore, 0.55% from steel mill waste and 2% ash from the thermal power plant "Nikola Tesla A" was adopted as the reputable mixture for cement making. For concrete making, the same cement mixture was used but with 2.1% of the same ash material added. The results showed possibility of further fly and bottom ash use as the cement and concrete material.

  9. COMPARATIVE STUDY OF HEAVY METALS IN BOTTOM ASH FROM INCINERATORS AND OPEN PIT FROM HEALTHCARE FACILITIES IN GHANA

    Directory of Open Access Journals (Sweden)

    Richard Amfo-Otua

    2015-03-01

    Full Text Available Treatment of healthcare waste either by incinerating or open burning in a pit produces bottom ashes which contains heavy metals and other chemicals which are toxic, persistent and accumulate in the food chain resulting in adverse health effects in human and the environment. The study investigated the level of heavy metals in the ashes of thermally treated medical waste from four health care facilities in Ghana. Two batch of the ash samples were collected from two hospital incinerators and the other two from medical waste burnt in an open-pit. The samples were collected on different days but within the same month, stored and transported to Water Research Institute laboratory for heavy metals analysis. The concentrations of Pb, Cd, Cr and Hg were assessed using Atomic Absorption Spectrophotometry (AAS. The results proved that the concentrations of heavy metals were higher for the waste treated in the incinerator than those burnt in the open pit. The average concentration of the metals in the ashes were in the following decreasing order Pb>Cr>Hg>Cd. The mean concentration of Pb from the incinerated bottom ash was 147.5mg/kg and Cd was 2.5mg/kg whilst the open pit was (69.67mg/kg and (1.34mg/kg respectively. All the metals investigated exceeded the Dutch and Danish limit values for maximum permissible levels of heavy metals in good soil quality and therefore classified as harmful and toxic and therefore proper attention should be given to the ash disposal at the landfill sites.

  10. Potential Use of Malaysian Thermal Power Plants Coal Bottom Ash in Construction

    Directory of Open Access Journals (Sweden)

    Abdulhameed Umar Abubakar

    2012-11-01

    Full Text Available As Malaysia focuses its attention to the call for a “greener” culture, so did the engineers and those in the scientific community especially the construction industry who is a major contributor to the depletion of green house gases. The engineering and construction community has now taken up the challenge for the use of “green and recycled by-products” in construction. One of those by-products is the Coal Bottom Ash (CBA from thermal power plants that faces an increasing production running into hundreds of thousand tonnes in Malaysia alone, and its method of disposal is relegated to landfills alone with no other commercial usage. The construction industry is now forced to rethink on the utilization of the industrial by-products as supplementary materials due to the continuous depletion of natural aggregates in construction. A significant amount of research has been conducted elsewhere on CBA to ascertain its pozzolanic activity, compressive strength in concrete and mortar, durability, water absorption characteristics and density, in order to ensure its usage as a construction material. In this paper, a critical review of the strength characteristics of concrete and mortar as influenced by CBA as partial replacement of fine aggregate is presented based on the available information in the published literatures. Diverse physical and chemical properties of CBA from different power plants in Malaysia are also presented. The influence of different types, amounts and sources of CBA on the strength and bulk density of concrete is discussed. The setting time, workability and consistency as well as the advantages and disadvantages of using CBA in construction materials are also highlighted. An effective utilization of CBA in construction materials will significantly reduce the accumulation of the by-products in landfills and thus reduce environmental pollution.

  11. Reuse of MSWI bottom ash mixed with natural sodium bentonite as landfill cover material.

    Science.gov (United States)

    Puma, Sara; Marchese, Franco; Dominijanni, Andrea; Manassero, Mario

    2013-06-01

    The research described in this study had the aim of evaluating the reuse of incinerator slag, mixed with sodium bentonite, for landfill capping system components. A characterization was performed on pure bottom ash (BA) samples from an incinerator in the north of Italy. The results show that the BA samples had appropriate properties as covers. The compacted dry unit weight of the studied BA (16.2 kN m(-3)) was lower than the average value that characterizes most conventional fill materials and this can be considered advantageous for landfill cover systems, since the fill has to be placed on low bearing capacity ground or where long-term settlement is possible. Moreover, direct shear tests showed a friction angle of 43°, corresponding to excellent mechanical characteristics that can be considered an advantage against failure. The hydraulic conductivity tests indicated a steady-state value of 8 × 10(-10) m s(-1) for a mixture characterized by a bentonite content by weight of 10%, which was a factor 10 better than required by Italian legislation on landfill covers. The results from a swell index test indicated that fine bentonite swelled, even when divalent cations were released by the BA. The leaching behaviour of the mixture did not show any contamination issues and was far better than obtained for the pure BA. Thus, the BA-bentonite mixture qualified as a suitable material for landfill cover in Italy. Moreover, owing to the low release of toxic compounds, the proposed cover system would have no effect on the leachate quality in the landfill.

  12. Accelerated carbonation using municipal solid waste incinerator bottom ash and cold-rolling wastewater: Performance evaluation and reaction kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Chang, E-E [Department of Biochemistry, Taipei Medical University, 250 Wu-Hsing Street, Taipei City, Taiwan 110, Taiwan, ROC (China); Pan, Shu-Yuan [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Rd., Taipei City, Taiwan 10673, Taiwan, ROC (China); Yang, Liuhanzi [School of Environment, Tsinghua University, Haidin District, Beijing 100084 (China); Chen, Yi-Hung [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei City, Taiwan 10608, Taiwan, ROC (China); Kim, Hyunook [Department of Energy and Environmental System Engineering, University of Seoul (Korea, Republic of); Chiang, Pen-Chi, E-mail: pcchiang@ntu.edu.tw [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Rd., Taipei City, Taiwan 10673, Taiwan, ROC (China)

    2015-09-15

    Highlights: • Carbonation was performed using CO{sub 2}, wastewater and bottom ash in a slurry reactor. • A maximum capture capacity of 102 g CO{sub 2} per kg BA was achieved at mild conditions. • A maximum carbonation conversion of MSWI-BA was predicted to be 95% by RSM. • The CO{sub 2} emission from Bali incinerator could be expected to reduce by 6480 ton/y. • The process energy consumption per ton CO{sub 2} captured was estimated to be 180 kW h. - Abstract: Accelerated carbonation of alkaline wastes including municipal solid waste incinerator bottom ash (MSWI-BA) and the cold-rolling wastewater (CRW) was investigated for carbon dioxide (CO{sub 2}) fixation under different operating conditions, i.e., reaction time, CO{sub 2} concentration, liquid-to-solid ratio, particle size, and CO{sub 2} flow rate. The MSWI-BA before and after carbonation process were analyzed by the thermogravimetry and differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. The MSWI-BA exhibits a high carbonation conversion of 90.7%, corresponding to a CO{sub 2} fixation capacity of 102 g per kg of ash. Meanwhile, the carbonation kinetics was evaluated by the shrinking core model. In addition, the effect of different operating parameters on carbonation conversion of MSWI-BA was statistically evaluated by response surface methodology (RSM) using experimental data to predict the maximum carbonation conversion. Furthermore, the amount of CO{sub 2} reduction and energy consumption for operating the proposed process in refuse incinerator were estimated. Capsule abstract: CO{sub 2} fixation process by alkaline wastes including bottom ash and cold-rolling wastewater was developed, which should be a viable method due to high conversion.

  13. Impacts of natural weathering on the transformation/neoformation processes in landfilled MSWI bottom ash: a geoenvironmental perspective.

    Science.gov (United States)

    Saffarzadeh, Amirhomayoun; Shimaoka, Takayuki; Wei, Yunmei; Gardner, Kevin H; Musselman, Craig N

    2011-12-01

    Natural weathering processes are significant mechanisms that noticeably affect the fundamental nature of incineration ash residues. To provide a greater understanding of these processes, a MSWI (mono)landfill site in the north east of the US was selected as the target for systematic investigation of the natural weathering of bottom ash residues. Samples of various ages were collected from locations A (1 yr), B (10 yrs), C (13-14 yrs) and D (20 yrs) of the landfill in 2009. We investigated the phase transformation of the collected bottom ash particles, neoformation processes as well as the behavior and distribution of certain heavy metals (Cu, Pb, Zn, Ni, and Cr) in the neoformed phases using optical microscopy, SEM-EDX, and bulk examinations. at the preliminary stage, the waste metallic particles (Al, Fe, and Cu) and unstable minerals such as lime, portlandite, ettringite and hydrocalumite convert to oxide and hydroxide (hydrate) phases, calcite, alumina gel and gypsum. At the intermediate stage, the decomposition of melt products including magnetite spinels and metallic inclusions is triggered due to the partial dissolution of the melt glass. At the longer time horizon it is possible to track the breakdown of the glass phase, the extensive formation of calcite and anhydrite, Al-hydrates and more stable Fe-hydrates all through the older ash deposits. Among the dominant secondary phases, we propose the following order based on their direct metal uptake capacity: Fe-hydrates>Al-hydrates>calcite. Calcite was found to be the least effective phase for the direct sorption of heavy metals. Based on overall findings, a model is proposed that demonstrates the general trend of ash weathering in the landfill. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Cellular Mutagenicity and Heavy Metal Concentrations of Leachates Extracted from the Fly and Bottom Ash Derived from Municipal Solid Waste Incineration

    Science.gov (United States)

    Chen, Po-Wen; Liu, Zhen-Shu; Wun, Min-Jie; Kuo, Tai-Chen

    2016-01-01

    Two incinerators in Taiwan have recently attempted to reuse the fly and bottom ash that they produce, but the mutagenicity of these types of ash has not yet been assessed. Therefore, we evaluated the mutagenicity of the ash with the Ames mutagenicity assay using the TA98, TA100, and TA1535 bacterial strains. We obtained three leachates from three leachants of varying pH values using the toxicity characteristic leaching procedure test recommended by the Taiwan Environmental Protection Agency (Taiwan EPA). We then performed the Ames assay on the harvested leachates. To evaluate the possible relationship between the presence of heavy metals and mutagenicity, the concentrations of five heavy metals (Cd, Cr, Cu, Pb, and Zn) in the leachates were also determined. The concentrations of Cd and Cr in the most acidic leachate from the precipitator fly ash and the Cd concentration in the most acidic leachate from the boiler fly ash exceeded the recommended limits. Notably, none of the nine leachates extracted from the boiler, precipitator, or bottom ashes displayed mutagenic activity. This data partially affirms the safety of the fly and bottom ash produced by certain incinerators. Therefore, the biotoxicity of leachates from recycled ash should be routinely monitored before reusing the ash. PMID:27827867

  15. THE VALUE RELEVANCE OF THE FINANCIAL STATEMENTS’ BOTTOM LINES IN THE EMERGING EGYPTIAN CAPITAL MARKET

    OpenAIRE

    2015-01-01

    This study aims to examine the value relevance of the bottom lines of the financial statements in the Egyptian context after the inception of the new version of Egyptian Accounting Standards of 2006. Considering the tradition accounting value of conservatism and the firm size, the price and return models are operationalized using a sample of the most actively traded companies on the Egyptian Stock Market in the period from 2007-2009. Three important conclusions captured from th...

  16. The Utilization of Bottom Ash Coal for Briquette Products by Adding Teak Leaves Charcoal, Coconut Shell Charcoal, and Rice Husk Charcoal

    Directory of Open Access Journals (Sweden)

    Syafrudin Syafrudin

    2015-01-01

    Full Text Available The limitations of the availability of energy sources especially fuel oil has become a serious threat for the society. The use of coal for energy source as the replacement of fuel oil, in one hand, is very profitable, but on the other hand, will cause problem which is the coal ash residue. This coal ash is a by-product of coal combustion. This coal ash contains bottom ash. Through this observation, the bottom ash can be processed to be charcoal if added by teak leaves, coconut shell, and rice husk. Also, this observation needs to add binder materials for further processing in order to form briquette. It can be used as alternative fuel, the utilization of bottom ash and biomass will give positive impact to the environment. This observation was conducted by using compositions such as bottom ash, teak leaves, coconut shell, and rice husk. The treatment was using comparison 100%:0% ; 80%:20% ; 60%:40% ; 50%:50% ; 40%:60% ; 20%:80% ; 0%:100%. The result that the best briquette was on the composition of 20% bottom ash : 80% coconut shell. The characteristic values from that composition were moisture content of 3.45%, ash content of 17,32%, calorific value of 7.945,72 Cal/gr, compressive strength of 2,18 kg/cm2, level of CO of 105 mg/m3, and heavy metals Cu of 29,83 µg/g and  Zn 32,99 µg/g. The characteristic value from each briquette composition treatment showed that the increasing usage proportion of biomass as added material for briquette was able to increase its moisture content and calorific value. Besides, it is also able to decrease its ash content and compressive strength

  17. Temperature development in a modern municipal solid waste incineration (MSWI) bottom ash landfill with regard to sustainable waste management.

    Science.gov (United States)

    Klein, R; Baumann, T; Kahapka, E; Niessner, R

    2001-05-30

    Municipal solid waste is treated in incineration plants to reduce the volume, the toxicity and the reactivity of the waste. The final product, municipal solid waste incineration (MSWI) bottom ash, was considered as a material with a low reactivity, which can safely be deposited in a MSWI bottom ash landfill, or which can be used, e.g. in road construction after further treatment. However, temperature measurements in MSWI bottom ash landfills showed temperatures up to 90 degrees C, caused by exothermic reactions within the landfill. Such high temperatures may affect the stability of the flexible polymer membrane liner (FML) and may also lead to an accelerated desiccation of the clay barrier. At the beginning of this study it was uncertain whether those reported results would be applicable to modern landfills, because the treatment techniques in MSWI and landfills have changed, bottom and fly ash are stored separately, and the composition of the incinerated waste has changed significantly since the publication of those results. The aim of this study was to gain detailed knowledge of temperature development under standard disposal conditions in relation to the rate of ash disposal, the variation of layer thickness, and the environmental conditions in a modern landfill. Temperatures were measured at nine levels within the body of a landfill for a period of nearly 3 years. Within 7 months of the start of the disposal, a temperature increase of up to 70 degrees C within the vertical centre of the disposal was observed. In the upper and central part of the landfill this initial temperature increase was succeeded by a decrease in temperature. The maximum temperature at the time of writing (May 2000) is about 55 degrees C in the central part of the landfill. The maximum temperature (45.9 degrees C) at the FML was reached 17 months after the start of the deposition. Since then the temperatures decreased at a rate of 0.6 degrees C per month. Temperature variation within each

  18. Accelerated carbonation using municipal solid waste incinerator bottom ash and cold-rolling wastewater: Performance evaluation and reaction kinetics.

    Science.gov (United States)

    Chang, E-E; Pan, Shu-Yuan; Yang, Liuhanzi; Chen, Yi-Hung; Kim, Hyunook; Chiang, Pen-Chi

    2015-09-01

    Accelerated carbonation of alkaline wastes including municipal solid waste incinerator bottom ash (MSWI-BA) and the cold-rolling wastewater (CRW) was investigated for carbon dioxide (CO2) fixation under different operating conditions, i.e., reaction time, CO2 concentration, liquid-to-solid ratio, particle size, and CO2 flow rate. The MSWI-BA before and after carbonation process were analyzed by the thermogravimetry and differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. The MSWI-BA exhibits a high carbonation conversion of 90.7%, corresponding to a CO2 fixation capacity of 102g perkg of ash. Meanwhile, the carbonation kinetics was evaluated by the shrinking core model. In addition, the effect of different operating parameters on carbonation conversion of MSWI-BA was statistically evaluated by response surface methodology (RSM) using experimental data to predict the maximum carbonation conversion. Furthermore, the amount of CO2 reduction and energy consumption for operating the proposed process in refuse incinerator were estimated. Capsule abstract: CO2 fixation process by alkaline wastes including bottom ash and cold-rolling wastewater was developed, which should be a viable method due to high conversion.

  19. Utilisation of MSWI bottom ash as sub-base in road construction: first results from a large-scale test site.

    Science.gov (United States)

    Hjelmar, Ole; Holm, Jesper; Crillesen, Kim

    2007-01-31

    The preferred management option for municipal solid waste incinerator (MSWI) bottom ash in Denmark is utilisation rather than landfilling, but the current environmental quality criteria for bottom ash to be utilised in bulk quantities are rather strict. To evaluate the impact and risk assessments, upon which those criteria are based, a large-scale test site has been established. Three different MSWI bottom ashes have been used as sub-base in six test units ranging from 100 to 200 m2 with top covers of asphalt, flagstones and pebbles, respectively. All units, except one, are equipped with bottom liners and leachate collection equipment. The test site provides information on the leachate quality and quantity as a function of time under different conditions and on the flow pattern in asphalt and flagstone covered roads and squares with MSWI bottom ash sub-base. In addition, the leaching behaviour of the bottom ashes has been studied in the laboratory. The test site was established in October 2002 and the project is still ongoing. Water balance results indicate that the water flow distribution is strongly influenced by lateral flow on or in the upper part of the bottom ash layer and possibly by preferential flow. Comparisons between eluates from laboratory leaching tests on the bottom ashes and observations of the leachate from the site as a function of L/S show fairly good agreement for salts but less agreement for some trace elements. Most likely, this is partly due to the fact that the pH observed in the leachate from the field sites is lower than that observed in the eluates from the laboratory leaching tests.

  20. Metallic elements occurrences within metallic fragments in the municipal waste incineration bottom ash

    Science.gov (United States)

    Kowalski, Piotr; Kasina, Monika; Michalik, Marek

    2017-04-01

    Bottom ash (BA) from municipal solid waste incineration (MSWI) is composed of grainy ash material, residual components and metallic fragments (from few µm up to 3-5 cm). Its mineral and chemical composition is related to the composition of the waste stream in the incinerator operational area. Wide use of thermal techniques in management of solid waste makes important the studies on valuable components and their distribution within the material in terms of their further processing. By using various valorization or extraction techniques it is possible to extend the range of its possible further application. To investigate metallic elements distribution within metallic fragments of the MSWI BA material produced in municipal waste incineration plant in Poland were collected in 2015 and 2016. BA and its components were investigated using spectroscopic methods of chemical analysis: ICP-OES, ICP-MS, LECO and EDS (used for microanalysis during SEM observations). BA is a material rich in Si (22.5 wt%), Ca (13.4 wt%), Fe (4 wt%), Al (5.2 wt%) and Na (3.5 wt%), composed of equal part of amorphous (silicate glass dominated) and crystalline phase (rich in silicates, aluminosilicates, oxides of non- and metallic elements and sulphates). The content of metallic elements (Al, Fe, Mg, Ti, Mn, Cr, Ni, Sc, Mo, Cu, Pb, Zn, Sn) is 11.5 wt% with domination of Al (5.2 wt%) and Fe (4 wt%) and elevated values of Mg (1 wt%), Ti (0.54 wt%), Cu (0.26 wt%) and Zn (0.27 wt%) (Kowalski et al., 2016). They were mostly concentrated in the form of metallic fragments, mainly as metallic inclusions in the size of 1-20 µm and separated metallic grains in the size of 50-300 µm. Metallic fragments present in the BA are characterized by their composition heterogeneity and various oxygen content. Fragments are rarely composed of single metallic element and usually in their composition up to few main elements dominated over others. The most common were Fe-, Al- and Zn-rich fragments forming respectively

  1. Use of leaching tests to quantify trace element release from waste to energy bottom ash amended pavements.

    Science.gov (United States)

    Roessler, Justin G; Townsend, Timothy G; Ferraro, Christopher C

    2015-12-30

    A series of roadway tests strips were paved on-site at a landfill in Florida, U.S. Waste to energy (WTE) bottom ash was used as a partial course aggregate replacement in a hot mix asphalt (HMA) and a Portland cement concrete (PCC) pavement, along with control HMA and PCC sections. This allowed for a comparison of the relative degree of leaching between both materials (HMA and PCC) as well as between the ash-amended and control pavements. Batch and monolithic tank leaching tests were conducted on the pavements. Testing of the PCC samples demonstrated that Mo and Al were elevated above regulatory thresholds for both the control and ash amended samples. Further leach testing demonstrated that the release of Mo was likely from the PCC and not a result of the inclusion of the BA into pavement. Batch leach testing of ash-amended HMA samples revealed Sb as a constituent of potential concern. The results of the monolith leaching test displayed leaching of Sb within the same order of magnitude as the regulatory threshold. Calculation of the leachability index (LI) for Sb found that it would have limited mobility when incorporated in the HMA matrix. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. LCA of management strategies for RDF incineration and gasification bottom ash based on experimental leaching data.

    Science.gov (United States)

    Di Gianfilippo, Martina; Costa, Giulia; Pantini, Sara; Allegrini, Elisa; Lombardi, Francesco; Astrup, Thomas Fruergaard

    2016-01-01

    The main characteristics and environmental properties of the bottom ash (BA) generated from thermal treatment of waste may vary significantly depending on the type of waste and thermal technology employed. Thus, to ensure that the strategies selected for the management of these residues do not cause adverse environmental impacts, the specific properties of BA, in particular its leaching behavior, should be taken into account. This study focuses on the evaluation of potential environmental impacts associated with two different management options for BA from thermal treatment of Refuse Derived Fuel (RDF): landfilling and recycling as a filler for road sub bases. Two types of thermal treatment were considered: incineration and gasification. Potential environmental impacts were evaluated by life-cycle assessment (LCA) using the EASETECH model. Both non-toxicity related impact categories (i.e. global warming and mineral abiotic resource depletion) and toxic impact categories (i.e. human toxicity and ecotoxicity) were assessed. The system boundaries included BA transport from the incineration/gasification plants to the landfills and road construction sites, leaching of potentially toxic metals from the BA, the avoided extraction, crushing, transport and leaching of virgin raw materials for the road scenarios, and material and energy consumption for the construction of the landfills. To provide a quantitative assessment of the leaching properties of the two types of BA, experimental leaching data were used to estimate the potential release from each of the two types of residues. Specific attention was placed on the sensitivity of leaching properties and the determination of emissions by leaching, including: leaching data selection, material properties and assumptions related to emission modeling. The LCA results showed that for both types of BA, landfilling was associated with the highest environmental impacts in the non-toxicity related categories. For the toxicity

  3. Improved electrical efficiency and bottom ash quality on waste combustion plants. Appendix A11 to A14

    Energy Technology Data Exchange (ETDEWEB)

    Hedegaard Madsen, O.; Boejer, M.; Jensen, Peter A.; Dam-Johansen, K.; Lundtorp, K. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Mogensen, Erhardt (Babcock and Wilcox Voelund A/S, Glostrup (Denmark))

    2010-07-01

    Investigations making it possible to evaluate and further develop concepts to improve electrical efficiency in a waste combustion plant were performed. Furthermore, one objective of the study was to investigate the possibilities of improving waste bottom ash leaching properties by use of a rotary kiln treatment. The project work included construction of a bench-scale rotary kiln, performing ash rotary kiln treatment experiments, conducting gas suction probe measurements on a waste incineration plant and making some concept evaluations. The influence of the rotary kiln thermal treatment on the leaching of Ca, Al, Si, Mg, Ba, Sr, Cl, Cu, Pb, Zn, Cr, Mo, sulfate, DOC and carbonate was determined. As a result of these tests, the rotary kiln thermal treatment of bottom ashes can be recommended for reducing the leaching of Cu, Pb, Cl, Zn and DOC; however, an increased leaching of Cr and Mo should be expected. The combustion conditions above the grate of a waste incineration plant were investigated and the release and concentration of volatile ash species in the flue gas such as Cl, Na, K, Ca, Pb, Zn and S were measured. The conducted measurements show that flue gas from grate sections 3 and 4 can produce a sufficiently hot flue gas that contains only low concentrations of corrosive species, and therefore can be used to increase superheater temperatures. Implementation of the so-called flue gas split concept together with other steam circle modifications on a waste combustion plant, and using a reasonable increase in final steam temperature from 400 to 500 deg. C, have the potential to increase electrical efficiency from 24 to 30% (with respect to lower fuel heating value) in a waste combustion plant. The appendices deal with electrical efficiency by dividing the combustion products; release of potentially corrosive constituents from the grate; CFD modeling of grate with and without vertical divider. (Author)

  4. PERBANDINGAN NILAI KALOR BIOBRIKET YANG TERBUAT DARI BOTTOM ASH LIMBAH PLTU DAN BIOMASSA CANGKANG KOPI DENGAN VARIASI KOMPOSISI DAN JENIS PENGIKAT YANG BERBEDA

    Directory of Open Access Journals (Sweden)

    Budi Gunawan

    2015-12-01

    Full Text Available Tujuan dari penelitian ini adalah membuat biobriket dari bahan bottom ash limbah Pembangkit Listrik Tenaga Uap (PLTU dengan biomassa cangkang kopi dengan zat pengikat tetes tebu serta menguji nilai kalor yang dihasilkan. Metode yang digunakan dalam penelitian ini adalah; pembuatan biobriket dengan memvariasi komposisi antara bottom ash dengan biomassanya serta zat pengikat yang berbeda. Variasi komposisi antara biomassa cangkang kopi dengan bootom ash yang digunakan adalah 60% : 40% dan 70% : 30%, sedangkan bahan perekatnya menggunakan tetes tebu dan tepung kanji. Pengujian yang dilakukan adalah menguji nilai kalor dari biobriket yang dihasilkan menggunakan alat uji calloriboom. Dari hasil pengujian didapatkan biobriket dengan komposisi 70% biomassa cangkang kopi dan 30% bottom ash dengan pengikat tetes tebu mempunyai nilai kalor yang paling tinggi dibandingkan dengan komposisi dan pengikat yang lain dengan nilai kalor yang dihasilkan yaitu 2496,18 kal/gr. Nilai kalor ini dipengaruhi oleh kandungan karbon aktif yang terdapat pada arang cangkang kopi dan besar kecilnya kandungan carbon, oxygen dan ash yang dimiliki, semakin tinggi kandungan carbon dan oxygen maka makin tinggi pula nilai kalor yang kandungan kalor yang terdapat pada jenis perekat tetes tebu lebih tinggi dari pada tepung kanji. [Title: Comparison of Calorific Value of Biobriket Made of Bottom Ash Waste and Biomass Plant Shell Coffee by Varying Composition and Types of Binder] This study is aimed to make biobriket of bottom ash material waste biomass power plant and different binder of coffee shell (molasses as well as measuring the calorific value. The method in this study are by manufacturing biobricket by varying the composition of bottom ash with biomass and different binder. Biomass composition variation of the shell coffee and bottom ash are 60%:40% and 70%:30%. The binder used are molasses and starch. This experiment was carry out by measuring the calorific value of produced

  5. Numerical model for a watering plan to wash out organic matter from the municipal solid waste incinerator bottom ash layer in closed system disposal facilities.

    Science.gov (United States)

    Ishii, Kazuei; Furuichi, Toru; Tanikawa, Noboru

    2009-02-01

    Bottom ash from municipal solid waste incineration (MSWI) is a main type of waste that is landfilled in Japan. The long-term elution of organic matter from the MSWI bottom ash layers is a concern because maintenance and operational costs of leachate treatment facilities are high. In closed system disposal facilities (CSDFs), which have a roof to prevent rainfall from infiltrating into the waste layers, water must be supplied artificially and its quantity can be controlled. However, the quantity of water needed and how to apply it (the intensity, period and frequency) have not been clearly defined. In order to discuss an effective watering plan, this study proposes a new washout model to clarify a fundamental mechanism of total organic carbon (TOC) elution behavior from MSWI bottom ash layers. The washout model considers three phases: solid, immobile water and mobile water. The parameters, including two mass transfer coefficients of the solid-immobile water phases and immobile-mobile water phases, were determined by one-dimensional column experiments for about 2 years. The intensity, period and frequency of watering and other factors were discussed based on a numerical analysis using the above parameters. As a result, our washout model explained adequately the elution behavior of TOC from the MSWI bottom ash layer before carbonation occurred (pH approximately 8.3). The determined parameters and numerical analysis suggested that there is a possibility that the minimum amount of water needed for washing out TOC per unit weight of MSWI bottom ash layer could be determined, which depends on the two mass transfer coefficients and the depth of the MSWI bottom ash layer. Knowledge about the fundamental mechanism of the elution behavior of TOC from the MSWI bottom ash layer before carbonation occurs, clarified by this study, will help an effective watering plan in CSDFs.

  6. Fly and bottom ashes from biomass combustion as cement replacing components in mortars production: rheological behaviour of the pastes and materials compression strength.

    Science.gov (United States)

    Maschio, Stefano; Tonello, Gabriele; Piani, Luciano; Furlani, Erika

    2011-10-01

    In the present research mortar pastes obtained by replacing a commercial cement with the equivalent mass of 5, 10, 20 and 30 wt.% of fly ash or bottom ash from fir chips combustion, were prepared and rheologically characterized. It was observed that the presence of ash modifies their rheological behaviour with respect to the reference blend due to the presence, in the ashes, of KCl and K2SO4 which cause precipitation of gypsum and portlandite during the first hydration stages of the pastes. Hydrated materials containing 5 wt.% of ash display compression strength and absorption at 28 d of same magnitude as the reference composition; conversely, progressive increase of ash cause a continuous decline of materials performances. Conversely, samples tested after 180 d display a marked decline of compression strength, as a consequence of potassium elution and consequent alkali-silica reaction against materials under curing.

  7. Full factorial experimental design analysis of Rhodamine B removal from water using organozeolite from coal bottom ash

    Directory of Open Access Journals (Sweden)

    Raquel R. Alcântara, Rafael O. R. Muniz, Denise A. Fungaro

    2016-01-01

    Full Text Available Zeolitic material synthesized using coal bottom ash asraw materialwas modified by cationic surfactant. Raw bottom ash and zeolitic materials were characterized using various techniques to obtain its physical and chemical properties. Surfactant modified zeolite (SMZBA was used as alternative low-cost adsorbent for removal of Rhodamine B (RB dye from aqueous solution. Dye adsorption equilibrium was attained after 40 min of the contact time and adsorption kinetics were described by the pseudo second order kinetic model. Equilibrium adsorption data were adjusted using non-linear equations of the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R models. Error analysis showed that D-R was the most appropriate for fitting the experimental data.The reuse of the remaining solution generated from the synthesis of zeolite was effective. To optimize the operating conditions, the temperature, pH, adsorbent dosage and initial concentration of the dye were investigated by full factorial experimental design method; adsorbent dosage, initial concentration and interaction of the two were found as the most significant factors with P = 0.02 lower than 95% confidence level. The results showed that SMZBA is a good adsorbent for the removal of RB from aqueous effluent.

  8. Assessment of Pb-slag, MSWI bottom ash and boiler and fly ash for using as a fine aggregate in cement mortar.

    Science.gov (United States)

    Saikia, Nabajyoti; Cornelis, Geert; Mertens, Gilles; Elsen, Jan; Van Balen, Koenraad; Van Gerven, Tom; Vandecasteele, Carlo

    2008-06-15

    Three types of wastes, metallurgical slag from Pb production (SLG), the sand-sized (0.1-2 mm) fraction of MSWI bottom ash from a grate furnace (SF), and boiler and fly ash from a fluidised bed incinerator (BFA), were characterized and used to replace the fine aggregate during preparation of cement mortar. The chemical and mineralogical behaviour of these wastes along with the reactivities of the wastes with lime and the hydration behaviour of ordinary Portland cement paste with and without these wastes added were evaluated by various chemical and instrumental techniques. The compressive strengths of the cement mortars containing waste as a partial substitution of fine aggregates were also assessed. Finally, leaching studies of the wastes and waste containing cement mortars were conducted. SLG addition does not show any adverse affect during the hydration of cement, or on the compressive strengths behaviours of mortars. Formation of expansive products like ettringite, aluminium hydroxide and H2 gas due to the reaction of some constituents of BFA and SF with alkali creates some cracks in the paste as well as in the cement mortars, which lower the compressive strength of the cement mortars. However, utilization of all materials in cement-based application significantly improves the leaching behaviour of the majority of the toxic elements compared to the waste as such.

  9. Pilot scale evaluation of the BABIU process--upgrading of landfill gas or biogas with the use of MSWI bottom ash.

    Science.gov (United States)

    Mostbauer, P; Lombardi, L; Olivieri, T; Lenz, S

    2014-01-01

    Biogas or landfill gas can be converted to a high-grade gas rich in methane with the use of municipal solid waste incineration bottom ash as a reactant for fixation of CO2 and H2S. In order to verify results previously obtained at a laboratory scale with 65-90 kg of bottom ash (BA), several test runs were performed at a pilot scale, using 500-1000 kg of bottom ash and up to 9.2 Nm(3)/h real landfill gas from a landfill in the Tuscany region (Italy). The input flow rate was altered. The best process performance was observed at a input flow rate of 3.7 Nm(3)/(htBA). At this flow rate, the removal efficiencies for H2S were approximately 99.5-99%. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Thermal treatment of stabilized air pollution control residues in a waste incinerator pilot plant. Part 2: Leaching characteristics of bottom ashes.

    Science.gov (United States)

    Baun, Dorthe L; Christensen, Thomas H; Bergfeldt, Brita; Vehlow, Jürgen; Mogensen, Erhardt P B

    2004-02-01

    With the perspective of generating only one solid residue from waste incineration, co-feeding of municipal solid waste and air pollution control residues stabilized by the Ferrox process was investigated in the TAMARA pilot plant incinerator as described in Bergfeldt et al. (Waste Management Research, 22, 49-57, 2004). This paper reports on leaching from the combined bottom ashes. Batch leaching test, pH-static leaching tests, availability tests and column leaching tests were used to characterize the leaching properties. The leaching properties are key information in the context of reuse in construction or in landfilling of the combined residue. In general, the combined bottom ashes had leaching characteristics similar to the reference bottom ash, which contained no APC residue. However, As and Pb showed slightly elevated leaching from the combined bottom ashes, while Cr showed less leaching. The investigated combined bottom ashes had contents of metals comparable to what is expected at steady state after continuous co-feeding of APC residues. Only Cd and Pb were partly volatilized (30-40%) during the incineration process and thus the combined bottom ashes had lower contents of Cd and Pb than expected at steady state. Furthermore, a major loss of Hg was, not surprisingly, seen and co-feeding of Ferrox-products together with municipal solid waste will require dedicated removal of Hg in the flue gas to prevent a build up of Hg in the system. In spite of this, a combined single solid residue from waste incineration seems to be a significant environmental improvement to current technology.

  11. DNA damage induced by coal dust, fly and bottom ash from coal combustion evaluated using the micronucleus test and comet assay in vitro.

    Science.gov (United States)

    Matzenbacher, Cristina Araujo; Garcia, Ana Letícia Hilario; Dos Santos, Marcela Silva; Nicolau, Caroline Cardoso; Premoli, Suziane; Corrêa, Dione Silva; de Souza, Claudia Telles; Niekraszewicz, Liana; Dias, Johnny Ferraz; Delgado, Tânia Valéria; Kalkreuth, Wolfgang; Grivicich, Ivana; da Silva, Juliana

    2017-02-15

    Coal mining and combustion generating huge amounts of bottom and fly ash are major causes of environmental pollution and health hazards due to the release of polycyclic aromatic hydrocarbons (PAH) and heavy metals. The Candiota coalfield in Rio Grande do Sul, is one of the largest open-cast coal mines in Brazil. The aim of this study was to evaluate genotoxic and mutagenic effects of coal, bottom ash and fly ash samples from Candiota with the comet assay (alkaline and modified version) and micronucleus test using the lung fibroblast cell line (V79). Qualitative and quantitative analysis of PAH and inorganic elements was carried out by High Performance Liquid Chromatography (HPLC) and by Particle-Induced X-ray Emission (PIXE) techniques respectively. The samples demonstrated genotoxic and mutagenic effects. The comet assay modified using DNA-glicosilase formamidopirimidina (FPG) endonuclease showed damage related to oxidative stress mechanisms. The amount of PAHs was higher in fly ash followed by pulverized coal. The amount of inorganic elements was highest in fly ash, followed by bottom ash. It is concluded that the samples induce DNA damage by mechanisms that include oxidative stress, due to their complex composition, and that protective measures have to be taken regarding occupational and environmental hazards.

  12. Removal of boron from ceramic industry wastewater by adsorption-flocculation mechanism using palm oil mill boiler (POMB) bottom ash and polymer.

    Science.gov (United States)

    Chong, Mei Fong; Lee, Kah Peng; Chieng, Hui Jiun; Syazwani Binti Ramli, Ili Izyan

    2009-07-01

    Boron is extensively used in the ceramic industry for enhancing mechanical strength of the tiles. The discharge of boron containing wastewater to the environment causes severe pollution problems. Boron is also dangerous for human consumption and causes organisms' reproductive impediments if the safe intake level is exceeded. Current methods to remove boron include ion-exchange, membrane filtration, precipitation-coagulation, biological and chemical treatment. These methods are costly to remove boron from the wastewater and hence infeasible for industrial wastewater treatment. In the present research, adsorption-flocculation mechanism is proposed for boron removal from ceramic wastewater by using Palm Oil Mill Boiler (POMB) bottom ash and long chain polymer or flocculant. Ceramic wastewater is turbid and milky in color which contains 15 mg/L of boron and 2000 mg/L of suspended solids. The optimum operating conditions for boron adsorption on POMB bottom ash and flocculation using polymer were investigated in the present research. Adsorption isotherm of boron on bottom ash was also investigated to evaluate the adsorption capacity. Adsorption isotherm modeling was conducted based on Langmuir and Freundlich isotherms. The results show that coarse POMB bottom ash with particle size larger than 2 mm is a suitable adsorbent where boron is removed up to 80% under the optimum conditions (pH=8.0, dosage=40 g bottom ash/300 ml wastewater, residence time=1h). The results also show that KP 1200 B cationic polymer is effective in flocculating the suspended solids while AP 120 C anionic polymer is effective in flocculating the bottom ash. The combined cationic and anionic polymers are able to clarify the ceramic wastewater under the optimum conditions (dosage of KP 1200 B cationic polymer=100 mg/L, dosage of AP 120 C anionic polymer=50 mg/L, mixing speed=200 rpm). Under the optimum operating conditions, the boron and suspended solids concentration of the treated wastewater were

  13. Experimental evaluation of two different types of reactors for CO2 removal from gaseous stream by bottom ash accelerated carbonation.

    Science.gov (United States)

    Lombardi, L; Carnevale, E A; Pecorini, I

    2016-12-01

    Low methane content landfill gas may be enriched by removing carbon dioxide. An innovative process, based on carbon dioxide capture and storage by means of accelerated carbonation of bottom ash is proposed and studied for the above purpose. Within this research framework we devoted a preliminary research activity to investigate the possibility of improving the way the contact between bottom ash and landfill gas takes place: this is the scope of the work reported in this paper. Two different types of reactors - fixed bed and rotating drum - were designed and constructed for this purpose. The process was investigated at laboratory scale. As the aim of this phase was the comparison of the performances of the two different reactors, we used a pure stream of CO2 to preliminarily evaluate the reactor behaviors in the most favorable condition for the process (i.e. maximum CO2 partial pressure at ambient condition). With respect to the simple fixed bed reactor concept, some modifications were proposed, consisting of separating the ash bed in three layers. With the three layer configuration we would like to reduce the possibility for the gas to follow preferential paths through the ash bed. However, the results showed that the process performances are not significantly influenced by the multiple layer arrangement. As an alternative to the fixed bed reactor, the rotating drum concept was selected in order to provide continuous mixing of the solids. Two operating parameters were considered and varied during the tests: the filling ratio and the rotating speed. Better performances were observed for lower filling ratio while the rotating speed showed minor importance. Finally the performances of the two reactors were compared. The rotating drum reactor is able to provide improved carbon dioxide removal with respect to the fixed bed one, especially when the rotating reactor is operated at low filling ratio values and slow rotating speed values. Comparing the carbon dioxide

  14. Metals accumulations during thermal processing of sewage sludge - characterization of bottom ash and air pollution control (APC) residues

    Science.gov (United States)

    Kasina, Monika; Kowalski, Piotr R.; Michalik, Marek

    2016-04-01

    Due to increasing mass of sewage sludge, problems in its management have appeared. Over years sewage sludge was landfilled, however due to EU directives concerning environmental issues this option is no longer possible. This type of material is considered hazardous due to highly concentrated metals and harmful elements, toxic organic substances and biological components (e.g. parasites, microbes). Currently in Europe, incineration is considered to be the most reasonable method for sewage sludge treatment. As a result of sludge incineration significant amount of energy is recovered due to high calorific value of sewage sludge but bottom ash and APC residues are being produced. In this study we show the preliminary results of chemical and mineral analyses of both bottom ash and APC residues produced in fluidized bed boiler in sewage sludge incineration plant in Poland, with a special emphasis on metals which, as a part of incombustible fraction can accumulate in the residual materials after thermal processing. The bottom ash was a SiO2-P2O5-Fe2O3-CaO-Al2O3 dominated material. Main mineral phases identified in X-ray diffraction patterns were: quartz, feldspar, hematite, and phosphates (apatite and scholzite). The bottom ash was characterized by high content of Zn - 4472 mg kg-1, Cu - 665.5 mg kg-1, Pb - 138 mg kg-1, Ni - 119.5 mg kg-1, and interestingly high content of Au - 0.858 mg kg-1 The APC residues composition was dominated by soluble phases which represent more than 90% of the material. The XRD patterns indicated thenardite, halite, anhydrite, calcite and apatite as main mineral phases. The removal of soluble phases by dissolution in deionised water caused a significant mass reduction (ca. 3% of material remained on the filters). Calcite, apatite and quartz were main identified phases. The content of metals in insoluble material is relatively high: Zn - 6326 mg kg-1, Pb - 514.3 mg kg-1, Cu - 476.6 mg kg-1, Ni - 43.3 mg kg-1. The content of Cd, As, Se and Hg was

  15. Corrosivity and leaching behavior of controlled low-strength material (CLSM) made using bottom ash and quarry dust.

    Science.gov (United States)

    Naganathan, Sivakumar; Razak, Hashim Abdul; Hamid, Siti Nadzriah Abdul

    2013-10-15

    This paper reports the corrosivity and leaching behavior of CLSM made using two different industrial wastes i.e. bottom ash from an incineration facility and quarry dust. The leachate samples were derived from fresh and hardened CLSM mixtures, and studied for leaching and electrical resistivity. The release of various contaminants and the consequent environmental impact caused by the contaminants were studied by the measurement of contaminants in the bleed, in the leachate at 28 days, and on the leachate derived from crushed block and whole block leaching done over a period of 126 days. Results indicated that the CLSM mixtures are non corrosive; diffusion was the leaching mechanism; and the contaminants were found to be moderate to low mobility.

  16. Development of Ecoefficient Engineered Cementitious Composites Using Supplementary Cementitious Materials as a Binder and Bottom Ash Aggregate as Fine Aggregate

    Directory of Open Access Journals (Sweden)

    Jin Wook Bang

    2015-01-01

    Full Text Available The purpose of this study is to develop ecoefficient engineered cementitious composites (ECC using supplementary cementitious materials (SCMs, including fly ash (FA and blast furnace slag (SL as a binder material. The cement content of the ECC mixtures was replaced by FA and SL with a replacement rate of 25%. In addition, the fine aggregate of the ECC was replaced by bottom ash aggregate (BA with a substitution rate of 10%, 20%, and 30%. The influences of ecofriendly aggregates on fresh concrete properties and on mechanical properties were experimentally investigated. The test results revealed that the substitution of SCMs has an advantageous effect on fresh concrete’s properties; however, the increased water absorption and the irregular shape of the BA can potentially affect the fresh concrete’s properties. The substitution of FA and SL in ECC led to an increase in frictional bond at the interface between PVA fibers and matrix, improved the fiber dispersion, and showed a tensile strain capacity ranging from 3.3% to 3.5%. It is suggested that the combination of SCMs (12.5% FA and 12.5% SL and the BA aggregate with the substitution rate of 10% can be effectively used in ECC preparation.

  17. 城市生活垃圾焚烧炉渣中铅的溶出特性研究%Leaching Characteristic of Pb from MSWI Bottom Ash

    Institute of Scientific and Technical Information of China (English)

    孔庆娜; 姚俊

    2013-01-01

    The leaching characteristic of Pb from two types of municipal solid waste incinerator (MSWI) bottom ash,namely grate furnace MSWI bottom ash and fluidized bed MSWI bottom ash,was studied with batch titration procedure and Visual MINTEQ.The results showed the leaching of Pb depended on the pH.Furthermore,the leaching of Pb was controlled by the equilibrium of PbMoO4 for the two types of MSWI bottom ash.%利用浸出试验和Visual MINTEQ模型,对2种不同炉型的城市生活垃圾焚烧炉渣中铅的溶出特性进行了研究.结果表明,无论是炉排炉型生活垃圾焚烧炉渣还是流化床型生活垃圾焚烧炉渣,其铅的溶出行为均受pH的影响,并且受到PbMoO4溶解平衡的控制.

  18. Mass-balance estimation of heavy metals and selected anions at a landfill receiving MSWI bottom ash and mixed construction wastes.

    Science.gov (United States)

    Oygard, Joar Karsten; Gjengedal, Elin; Måge, Amund

    2005-08-31

    An estimation of the heavy metal and anion mass-balance was made for municipal solid waste incinerator bottom ash deposited at a construction and industrial waste landfill. The mass-balance was found by comparing the content of metals and anions in the landfill leachate to the metal and anion content in the deposited bottom ash. The discharge of heavy metals ranged from 0.001% for Pb to 0.55% for Cr, which is approximately at the same level as in regular municipal solid waste (MSW) landfills. Landfilled organic material and silicates from construction waste might have contributed to the retention of metals. Chloride, and to a lesser extent sulphate, appeared to be readily released from the landfill. It was estimated that a mass corresponding to 80% of the Cl- and 18% of the SO(4)2- in the bottom ash was discharged annually. Low retention, especially of chloride, may lead to a rapid decline in the discharge of this ion in the future when the landfilling of bottom ash is discontinued.

  19. Pilot-scale road subbase made with granular material formulated with MSWI bottom ash and stabilized APC fly ash: environmental impact assessment.

    Science.gov (United States)

    del Valle-Zermeño, R; Formosa, J; Prieto, M; Nadal, R; Niubó, M; Chimenos, J M

    2014-02-15

    A granular material (GM) to be used as road sub-base was formulated using 80% of weathered bottom ash (WBA) and 20% of mortar. The mortar was prepared separately and consisted in 50% APC and 50% of Portland cement. A pilot-scale study was carried on by constructing three roads in order to environmentally evaluate the performance of GM in a real scenario. By comparing the field results with those of the column experiments, the overestimations observed at laboratory scale can be explained by the potential mechanisms in which water enters into the road body and the pH of the media. An exception was observed in the case of Cu, whose concentration release at the test road was higher. The long-time of exposure at atmospheric conditions might have favoured oxidation of organic matter and therefore the leaching of this element. The results obtained showed that immobilization of all heavy metals and metalloids from APC is achieved by the pozzolanic effect of the cement mortar. This is, to the knowledge of the authors, the only pilot scale study that is considering reutilization of APC as a safe way to disposal.

  20. Dioxin-like compound compositional profiles of furnace bottom ashes from household combustion in Poland and their possible associations with contamination status of agricultural soil and pine needles

    Energy Technology Data Exchange (ETDEWEB)

    Wyrzykowska, B.; Hanari, N.; Orlikowska, A.; Yamashita, N.; Falandysz, J. [University of Gdansk, Gdansk (Poland)

    2009-06-15

    A compositional profile of PCDDs, PCDFs, non- and mono-ortho PCBs, and PCNs of several type furnace bottom ashes obtained after the heating muffle stove for domestic use combustion of hard coal, coke, wood, and solid domestic waste mixture have been examined as possible contributors to environmental diffusion with these compounds in Poland. The uppermost concentration of dioxin-like compounds with 2.0 ng TEQ kg{sup -1} dry weight found for wood ash was dominated by PCDDs and PCDFs, while for other types of ashes were in the range from 0.052 ng TEQ kg{sup -1} to 0.67 ng TEQ kg{sup -1} dry weight. The multivariate statistical analysis displayed some compositional similarity of PCDDs, PCDFs and PCNs between the ashes and environmental pine needle or agricultural soil matrices collected in Poland.

  1. Analysis and interpretation of the leaching behaviour of waste thermal treatment bottom ash by batch and column tests.

    Science.gov (United States)

    Di Gianfilippo, Martina; Costa, Giulia; Verginelli, Iason; Gavasci, Renato; Lombardi, Francesco

    2016-10-01

    This paper investigates the leaching behaviour of specific types of waste thermal treatment bottom ash (BA) as a function of both pH and the liquid-to-solid ratio (L/S). Specifically, column percolation tests and different types of batch tests (including pH-dependence) were applied to BA produced by hospital waste incineration (HW-I), Refuse Derived Fuel (RDF) gasification (RDF-G) and RDF incineration (RDF-I). The results of these tests were interpreted applying an integrated graphical and modelling approach aimed at identifying the main mechanisms (solubility, availability or time-controlled dissolution and diffusion) governing the release of specific constituents from each type of BA. The final aim of this work was in fact to gain insight on the information that can be provided by the leaching tests applied, and hence on which ones may be more suitable to apply for assessing the leaching concentrations expected in the field. The results of the leaching tests showed that the three samples of analysed BA presented differences of orders of magnitude in their leaching behaviour, especially as a function of pH, but also in terms of the L/S. These were mainly related to the differences in mineralogy of the samples. In addition, for the same type of bottom ash, the comparison between the results of batch and percolation column tests, expressed in terms of cumulative release, showed that for some constituents (e.g. Mg for HW-I BA and Cu for RDF-G BA) differences of over one order of magnitude were obtained due to variations in pH and DOC release. Similarly, the eluate concentrations observed in the percolation tests, for most of the investigated elements, were not directly comparable with the results of the pH-dependence tests. In particular, in some cases the percolation test results showed eluate concentrations of some constituents (e.g. K and Ca in HW-I BA) of up to one order of magnitude higher than the values obtained from the pH-dependence experiments at the same p

  2. Mechanical Properties of High Strength Concrete Containing Coal Bottom Ash and Oil-Palm Boiler Clinker as Fine Aggregates

    Directory of Open Access Journals (Sweden)

    Soofinajafi Mahmood

    2016-01-01

    Full Text Available This research aims to utilize Coal Furnace Bottom ash (CBA and Oil-Palm Boiler Clinker (OPBC as fine aggregate in concrete mix proportions. They are solid wastes from power plant and Oil Palm industry, respectively. Since these by-products do not have any primary use and are pure waste, an opportunity to use them as aggregate in concrete industry not only is economical but also will be an environmental friendly opportunity leading towards a more sustainable production chain. CBA and OPBC sands had similar grading to normal sand but have lower density and higher water absorption. In a high strength concrete, normal sand was replaced up to 25% with either CBA or OPBC. Test results showed that although water absorption of these wastes was more than normal sand but the slump value of concrete containing each of these wastes showed that these concretes had good workability. All mixes containing these wastes had slightly lower compressive strength at early ages and equivalent or higher compressive strength at later ages compared to control mix. The 28-day compressive strength of these concretes was in the range of 69–76 MPa which can be categorized as high strength concrete. In general, the performance of OPBC was better than CBA at 25% replacement level. However, it is recommended that at least 12.5% of total volume of fine aggregate in a high strength concrete is used of CBA or OPBC.

  3. Copper leaching of MSWI bottom ash co-disposed with refuse: effect of short-term accelerated weathering.

    Science.gov (United States)

    Su, Lianghu; Guo, Guangzhai; Shi, Xinlong; Zuo, Minyu; Niu, Dongjie; Zhao, Aihua; Zhao, Youcai

    2013-06-01

    Co-disposal of refuse with municipal solid waste incinerator (MSWI) bottom ash (IBA) either multi-layered as landfill cover or mixed with refuse could pose additional risk to the environment because of enhanced leaching of heavy metals, especially Cu. This study applied short-term accelerated weathering to IBA, and monitored the mineralogical and chemical properties of IBA during the weathering process. Cu extractability of the weathered IBA was then evaluated using standard leaching protocols (i.e. SPLP and TCLP) and co-disposal leaching procedure. The results showed that weathering had little or no beneficial effect on Cu leaching in SPLP and TCLP, which can be explained by the adsorption and complexation of Cu with DOM. However, the Cu leaching of weathered IBA was reduced significantly when situated in fresh simulated landfill leachate. This was attributed to weakening Cu complexation with fulvic acid or hydrophilic fractions and/or intensifying Cu absorption to neoformed hydr(oxide) minerals in weathered IBA. The amount of total leaching Cu and Cu in free or labile complex fraction (the fraction with the highest mobility and bio-toxicity) of the 408-h weathered IBA were remarkably decreased by 86.3% and 97.6% in the 15-day co-disposal leaching test. Accelerated weathering of IBA may be an effective pretreatment method to decrease Cu leaching prior to its co-disposal with refuse. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Potential for leaching of heavy metals in open-burning bottom ash and soil from a non-engineered solid waste landfill.

    Science.gov (United States)

    Gwenzi, Willis; Gora, Dorcas; Chaukura, Nhamo; Tauro, Tonny

    2016-03-01

    Bottom ash from open-burning of municipal waste practised in developing countries poses a risk of heavy metal leaching into groundwater. Compared to incineration ash, there is limited information on heavy metal leaching from open-burning ash and soil from non-engineered landfills. Batch and column experiments were conducted to address three specific objectives; (1) to determine aqua regia extractable concentrations of heavy metals in fresh ash, old ash and soil from beneath the landfill, (2) to determine the relationship between heavy metal leaching, initial and final pH of leaching solution, and aqua regia extractable concentrations, and (3) to determine the breakthrough curves of heavy metals in ashes and soil. Aqua regia extractable concentrations of Cd, Zn, Mn, Cu, Ni and Pb were significantly higher (p heavy metals were not correlated with aqua regia extractable concentrations. Final pH of leachate rebounded to close to original pH of the material, suggesting a putative high buffering capacity for all materials. Both batch and column leaching showed that concentrations of leached heavy metals were disproportionately lower (heavy metals was further evidenced by sigmoidal breakthrough curves. Heavy metal retention was attributed to precipitation, pH-dependent adsorption and formation of insoluble organo-metallic complexes at near-neutral to alkaline pH. Overall, the risk of heavy metal leaching from ash and soil from the waste dump into groundwater was low. The high pH and the presence of Zn, Fe, Mn and Cu make ash an ideal low-cost liming material and source of micronutrients particularly on acidic soils prevalent in sub-Saharan Africa.

  5. A Comparative Study of Fouling and Bottom Ash from Woody Biomass Combustion in a Fixed-Bed Small-Scale Boiler and Evaluation of the Analytical Techniques Used

    Directory of Open Access Journals (Sweden)

    Lara Febrero

    2015-05-01

    Full Text Available In this work, fouling and bottom ash were collected from a low-power boiler after wood pellet combustion and studied using several analytical techniques to characterize and compare samples from different areas and determine the suitability of the analysis techniques employed. TGA results indicated that the fouling contained a high amount of organic matter (70%. The XRF and SEM-EDS measurements revealed that Ca and K are the main inorganic elements and exhibit clear tendency in the content of Cl that is negligible in the bottom ash and increased as it penetrated into the innermost layers of the fouling. Calcite, magnesia and silica appeared as the major crystalline phases in all the samples. However, the bottom ash was primarily comprised of calcium silicates. The KCl behaved identically to the Cl, preferably appeared in the adhered fouling samples. This salt, which has a low melting point, condenses upon contact with the low temperature tube and played a crucial role in the early stages of fouling formation. XRD was the most useful technique applied, which provided a semi-quantitative determination of the crystalline phases. FTIR was proven to be inadequate for this type of sample. The XRF and SEM-EDS, techniques yield similar results despite being entirely different.

  6. Life cycle assessment of disposal of residues from municipal solid waste incineration: recycling of bottom ash in road construction or landfilling in Denmark evaluated in the ROAD-RES model.

    Science.gov (United States)

    Birgisdóttir, H; Bhander, G; Hauschild, M Z; Christensen, T H

    2007-01-01

    Two disposal methods for MSWI bottom ash were assessed in a new life cycle assessment (LCA) model for road construction and disposal of residues. The two scenarios evaluated in the model were: (i) landfilling of bottom ash in a coastal landfill in Denmark and (ii) recycling of bottom ash as subbase layer in an asphalted secondary road. The LCA included resource and energy consumption, and emissions associated with upgrading of bottom ash, transport, landfilling processes, incorporation of bottom ash in road, substitution of natural gravel as road construction material and leaching of heavy metals and salts from bottom ash in road as well as in landfill. Environmental impacts associated with emissions to air, fresh surface water, marine surface water, groundwater and soil were aggregated into 12 environmental impact categories: Global Warming, Photochemical Ozone Formation, Nutrient Enrichment, Acidification, Stratospheric Ozone Depletion, Human Toxicity via air/water/soil, Ecotoxicity in water/soil, and a new impact category, Stored Ecotoxicity to water/soil that accounts for the presence of heavy metals and very persistent organic compounds that in the long-term might leach. Leaching of heavy metals and salts from bottom ash was estimated from a series of laboratory leaching tests. For both scenarios, Ecotoxicity(water) was, when evaluated for the first 100 yr, the most important among the twelve impact categories involved in the assessment. Human Toxicity(soil) was also important, especially for the Road scenario. When the long-term leaching of heavy metals from bottom ash was evaluated, based on the total content of heavy metals in bottom ash, all impact categories became negligible compared to the potential Stored Ecotoxicity, which was two orders of magnitudes greater than Ecotoxicity(water). Copper was the constituent that gave the strongest contributions to the ecotoxicities. The most important resources consumed were clay as liner in landfill and the

  7. Bottom ash from fluidising bed boilers as filler material in district heating pipe culverts. Chemical and geotechnical characterisation; Pannsand som kringfyllnadsmaterial foer fjaerrvaermeroergravar. Kemisk och geoteknisk karaktaerisering av fluidbaeddsand

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Roger; Rogbeck, Jan; Suer, Pascal

    2004-01-01

    Bottom ashes from fluid bed boilers have been characterised, both geotechnically and chemically, in order to investigate the possibility to use them as filler material in district heating pipe culverts. Bottom ashes from both biofuel boilers and waste boilers are represented in this project. The companies which ashes have been characterised are Sundsvall Energi AB, Sydkraft OestVaerme AB, Sydkraft MaelarVaerme AB, Eskilstuna Miljoe och Energi, Stora Enso Fors, Soederenergi and Fortum Vaerme. A total of ten ashes have been analysed where three ashes originates from Sundsvall Energi AB, two from Sydkraft OestVaerme AB and one from the each of the remaining companies. The chemical analyses have been performed both on fresh ashes and on ashes aged for three months. The geotechnical analyses performed are grain size distribution, packing abilities and permeability. Chemical analyses performed are total content, available content, leaching tests (leaching both by shaking method and column procedure) and organic analyses (PAH, EOX, TOC, dioxin and fenol). The geotechnical analyses show that the ashes fulfils the demands that are put on the filler material used in district heating pipe culverts. When using the ashes in applications, light compaction should be performed due to the risk of crushing the material which may cause an increased amount of fine material. The leachability of fine material is larger than for coarse material. The ashes are relatively insensitive to precipitation. Bio fuel based bottom ashes have a lower content of environmental affecting substances than waste fuel based ashes. This is also shown in the leaching analyses. The leaching water from fresh ashes contains a higher concentration of leachable components than aged ashes. When aged the pH in the ashes decreases due to carbon uptake and hydration and this makes metals as Pb, Cu, Cr and Zn less mobile. On the other hand, an increase in leachability of Sb, Mo and SO{sub 4} is shown when the ashes

  8. 城市生活垃圾焚烧底灰的水热固化研究%Hydrothermal solidification of municipal solid waste incineration bottom ash

    Institute of Scientific and Technical Information of China (English)

    单成冲; 潘莉莉; 吴科; 潘晓辉; 景镇子

    2011-01-01

    利用水热技术对城市生活垃圾底灰进行资源化利用研究,将其固化为一种强度高、重金属溶出少的建筑材料.主要研究了添加消石灰固化生活垃圾底灰的硬化机理,并且为了100%利用垃圾焚烧灰,也研究了添加垃圾飞灰固化底灰的方法.同时还进行了重金属浸出试验,测试固化体中重金属溶出量.研究结果表明,托勃莫来石晶体的生成是影响固化体强度的主要原因,而且托勃莫来石的生成量越多,样品的强度越高.飞灰也可以作为一种固化添加剂对底灰进行水热固化,且添加飞灰的硬化机理和消石灰相同.经过水热固化,固化体的重金属溶出量可大大降低.水热技术有望成为一种城市生活垃圾底灰资源化利用的有效方法.%Solidification of municipal solid waste incineration (MSWI) bottom ash into a building material with high strength and less heavy metal dissolution has been carried out using a hydrothermal processing method. The hardening mechanism of hydrothermal solidification of MSWI bottom ash by adding slaked lime was investigated in this study. Moreover,leaching tests were also conducted to determine the amount of heavy metals dissolved from the solidified specimens. The experimental results showed that the strength development of the solidified specimens with slaked lime addition was due primarily to the tobermorite formation and the more the tobermorite formed,the higher the strength was. MSWI fly ash also could be used as an additive to solidify bottom ash,and the hardening effect of solidification was favored to be similar to that with slaked lime addition. Under the hydrothermal processing,the amount of heavy metals dissolved from the solidified specimens was reduced greatly. As such,the hydrothermal processing may have a high potential for recycling MSWI bottom ash.

  9. Assessment of the aerobic preparation and bottom ash addition as pretreatment steps before landfilling: impact on methanogenesis kinetics and leachate parameters.

    Science.gov (United States)

    Mansour, Alicia A; Motte, Antoine; Pallier, Virginie; Feuillade-Cathalifaud, Geneviève; Ponthieux, Arnaud

    2012-10-01

    This work focuses on assessing the impact of two types of waste pretreatment: addition of bottom ashes and aerobic pretreatment on both the onset and kinetics of methanogenesis and the evolution of different parameters in the leachate. It also studies the correlation between methane production and the different parameters measured in the leachate produced. A total of six 68-L pilots were thus used with fresh municipal solid waste (MSW) shredded to a 40-mm size. After 14 months of landfilling, the control has produced less than 10 NLkg(-1)DM, which corresponds to around 7% of its biochemical methane potential (BMP). Nevertheless, on one hand for aerobically pretreated waste, the lag phase before the onset of methanogenesis is significantly reduced to 0.9 month compared to more than 1 year for the control. In addition to that, on average 110 NLkg(-1)DM (90% of the BMP) is produced within around 6.5 months. On the other hand, the waste with added bottom ash shows a slight improvement of the lag phase over the control for one of the duplicate: 6.1 months of lag phase. At this stage, on average of 26 NLkg(-1)DM waste are detected (22% of the BMP) no final conclusion concerning the impact of bottom ashes could be made. The data obtained for the leachate parameters agrees with the observations on methane production. Statistical correlation study shows that the two components of the corrected PCA interpret 76% of the variability of the data: SUVA (specific UV absorbance at 254 nm) and HPI(*) (% of hydrophilic compounds) are identified as interesting parameters for following up the biodegradation in landfill conditions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Synthesis of zeolitic-type adsorbent material from municipal solid waste incinerator bottom ash and its application in heavy metal adsorption

    OpenAIRE

    Chiang, Yi Wai; Ghyselbrecht, Karel; Santos, Rafael; Meesschaert, Boudewijn; Martens, Johan

    2012-01-01

    Municipal solid waste incinerator (MSWI) bottom ash (BA) was converted to zeolitic-type adsorbent materials by hydrothermal conversion under strongly alkaline conditions. The conversion product was determined to be a mixture of sodium aluminum silicate hydrate (SASH) (Na2O·Al2O3·1.68SiO2·1.73H2O) and tobermorite (Ca5Si6O16(OH)2·4H2O). The BET specific surface area was 22.1 m2/g, which represented a significant gain compared to the BA (4.6 m2/g) due to the formation of micropores and mesopores...

  11. Preservation of natural aquatic ecosystems by application of bottom coal ash based bioreactor for in situ treatment of anthropogenic effluents

    Science.gov (United States)

    Anker, Y.; Nisnevitch, M.; Tal, M.; Cahan, R.; Michael, E.

    2012-12-01

    One consequence of global climate change is recharge decrease at sub tropical and Mediterranean regions to both the surface and the ground fresh water resources. As a general rule, when water source quantity is reduced, the level of salination, as well as chemical and biological pollutants, tends to increase. The situation is more severe whenever the drainage basin is (a) heavily populated from urban, industrial and agricultural areas, (b) has wide areas of thin or non soil cover and (c) has a karstic structure and morphology. These latter conditions are typical to many regions around the Middle East; whereas pollution hazard to Mid Eastern streams is greater than to those in more humid regions owing to their relative small size and poor dilution capacity. The consequence of this ongoing and increasing anthropogenic pollution is endangerment of natural aquatic habitats and due to decrease in fresh water supply availability also to human sustainability. The ecological impact may involve transition of ephemeral (Wadi) streams into intermittent ones with the accompanied biodiversity change or extinction once the pollution is extreme. The impact on indigenous human communities might be as severe owing to drinking water quality decrease and the consequent decrease id quantity as well as damage to dryland farming. In setting of operations applied to the Yarkon Taninim watershed (central Israel) management, a pilot biofilter facility for sustainable preservation and rehabilitation of natural fluvial ecosystems was tested. This biofilter is planned to operate through low impact concept assimilating natural treatment processes occurring during runoff recharge through a porous flow media. The facility is constructed out of several grain sizes of bottom coal ash aggregate, which was found to be a better microbial mats growing stratum, compared to common natural aggregates such as tuff and lime pebbles (and also has an EPA directive for wastewater treatment). The biofilter is

  12. INTRINSIC FACTORS AND FIRM FINANCIAL ANALYSIS WITH TRIPPLE BOTTOM LINES AS INTERVENING VARIABLE AGAINST FIRM VALUE Empirical Studies on Property and Real Estate Companies Year 2010-2013

    Directory of Open Access Journals (Sweden)

    Mia Andika Sari

    2016-09-01

    Full Text Available This research conducted to examine the influence of intrinsic factors which being peroxided with Capital Structure, Firm Size, Firm Age and Financial factors that being peroxided with liquidity, profitability also with another activities using triple bottom lines as Intervening Variable against Firm Value of Property Industries. The data that being used in this study were obtained from published financial statements during the period 2010 to 2013, as well as annual reports that can be accessed through the IDX website. Data analysis technique used in this study is a regression with panel data and path analysis. The results of this research showed that intrinsic factors and financial variables have a significant influence on the firm value, as well as intrinsic factors and financial variables have a significant influence on the triple bottom lines. From the results of path analysis demonstrated that the indirect effect using the triple bottom lines as a intervening variable was greater than the direct effect.

  13. Use of waste materials--Bottom Ash and De-Oiled Soya, as potential adsorbents for the removal of Amaranth from aqueous solutions.

    Science.gov (United States)

    Mittal, Alok; Kurup Krishnan, Lisha; Gupta, Vinod K

    2005-01-31

    Bottom Ash, a power plan t waste material and De-Oiled Soya, an agriculture waste product were successfully utilized in removing trisodium 2-hydroxy-1-(4-sulphonato-1-naphthylazo)naphthalene-3,6-disulphonate--a water-soluble hazardous azo dye (Amaranth). The paper incorporates thermodynamic and kinetic studies for the adsorption of the dye on these two waste materials as adsorbents. Characterization of each adsorbent was carried out by I.R. and D.T.A. curves. Batch adsorption studies were made by measuring effects of pH, adsorbate concentration, sieve size, adsorbent dosage, contact time, temperature etc. Specific rate constants for the processes were calculated by kinetic measurements and a first order adsorption kinetics was observed in each case. Langmuir and Freundlich adsorption isotherms were applied to calculate thermodynamic parameters. The adsorption on Bottom Ash takes place via film diffusion process at lower concentrations and via particle diffusion process at higher concentrations, while in the case of De-Oiled Soya process only particle diffusion takes place in the entire concentration range.

  14. Separation Process of Municipal Solid Waste Incineration Bottom Ash%生活垃圾焚烧炉渣分选处理工艺研究

    Institute of Scientific and Technical Information of China (English)

    黄炳辉

    2013-01-01

      通过一个实例,分析介绍了生活垃圾焚烧炉渣分选处理的一种工艺。实践证明:综合利用破碎、筛分、磁力分选、跳汰分选、摇床分选等固废处理技术,对炉渣进行分选预处理,可有效回收利用Fe、Cu、Al等废旧金属,有效分离收集未燃尽的剩余垃圾,并妥善处理,从而使炉渣的性质满足资源化利用的技术要求,变废为宝。%This article takes an example to introduce a separation process of municipal solid waste incineration bottom ash .It has proven that sScrap metal like iron ,copper and aluminum can be recycled and fully used by using the combination technology such as crushing ,screening ,Magnetic ,jigging ,oscillating ,etc .This method is also very efficient for unburnt residual waste's separation and treatment ,so as to make sure that bottom ash can be utilized completely .

  15. Process development for the removal and recovery of hazardous dye erythrosine from wastewater by waste materials-Bottom Ash and De-Oiled Soya as adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Alok [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal 462007 (India)]. E-mail: aljymittal@yahoo.co.in; Mittal, Jyoti [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal 462007 (India); Kurup, Lisha [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal 462007 (India); Singh, A.K. [Department of Applied Chemistry, University Institute of Technology, RGPV, Bhopal 462036 (India)

    2006-11-02

    Erythrosine is a water-soluble xanthene class of dye. It is widely used as colorant in foods, textiles, drugs and cosmetics. It is highly toxic, causes various types of allergies, thyroid activities, carcinogenicity, DNA damage behaviour, neurotoxicity and xenoestrogen nature in the humans and animals. The photochemical and biochemical degradation of the erythrosine is not recommended due to formation of toxic by-products. The present paper is an attempt to remove erythrosine from wastewater using adsorption over Bottom Ash-a power plant waste and De-Oiled Soya-an agricultural waste. Under the batch studies, effect of concentration of dye, temperature, pH of the solution, dosage of adsorbents, sieve size of adsorbents, etc., have been studied for the uptake of the dye over both adsorbents. The adsorption process verifies Langmuir and Freundlich adsorption isotherms in both the cases and based on the data different thermodynamic parameters have been evaluated. Batch studies also include kinetic measurements, rate constant study, mass transfer behaviour and establishment of mechanistic pathway for both the cases. For the bulk removal of the dye column operations have been carried out and breakthrough capacities of the Bottom Ash and De-Oiled Soya columns have been calculated. Attempts have also been made for the recovery of the adsorbed dye from exhausted columns by eluting dilute NaOH and more than 90% of the dye was recovered.

  16. Variation of the phytotoxicity of municipal solid waste incinerator bottom ash on wheat (Triticum aestivum L.) seed germination with leaching conditions.

    Science.gov (United States)

    Phoungthong, Khamphe; Zhang, Hua; Shao, Li-Ming; He, Pin-Jing

    2016-03-01

    Municipal solid waste incinerator bottom ash (MSWIBA) has long been regarded as an alternative building material in the construction industry. However, the pollutants contained in the bottom ash could potentially leach out and contaminate the local environment, which presents an obstacle to the reuse of the materials. To evaluate the environmental feasibility of using MSWIBA as a recycled material in construction, the leaching derived ecotoxicity was assessed. The leaching behavior of MSWIBA under various conditions, including the extractant type, leaching time, liquid-to-solid (L/S) ratio, and leachate pH were investigated, and the phytotoxicity of these leachates on wheat (Triticum aestivum L.) seed germination was determined. Moreover, the correlation between the germination index and the concentrations of various chemical constituents in the MSWIBA leachates was assessed using multivariate statistics with principal component analysis and Pearson's correlation analysis. It was found that, heavy metal concentrations in the leachate were pH and L/S ratio dependent, but were less affected by leaching time. Heavy metals were the main pollutants present in wheat seeds. Heavy metals (especially Ba, Cr, Cu and Pb) had a substantial inhibitory effect on wheat seed germination and root elongation. To safely use MSWIBA in construction, the potential risk and ecotoxicity of leached materials must be addressed.

  17. A Case Study of Landfill Leachate Using Coal Bottom Ash for the Removal of Cd2+, Zn2+ and Ni2+

    Directory of Open Access Journals (Sweden)

    Julia Ayala

    2016-11-01

    Full Text Available The removal of Cd2+, Zn2+ and Ni2+ by coal bottom ash has been investigated. In single metal system, metal uptake was studied in batch adsorption experiments as a function of pH (2–3, contact time (5–180 min, initial metal concentration (50–400 mg/L, adsorbent concentration (5–40 g/L, particle size, and ionic strength (0–1 M NaCl. Removal percentages of metals ions increased with increasing pH and dosage. Removal efficiency at lower concentrations was greater than at higher values. The maximum amount of metal ion adsorbed in milligrams per gram was 35.4, 35.1 and 34.6 mg/g for Zn2+, Cd2+ and Ni2+, respectively, starting out from an initial solution at pH 3. Simultaneous removal of Zn2+, Cd2+ and Ni2+ ions from ternary systems was also investigated and compared with that from single systems. Cd2+ uptake was significantly affected by the presence of competing ions at pH 2. The results obtained in the tests with landfill leachate showed that bottom ash is effective in simultaneously removing several heavy metals such as Ni, Zn, Cd, As, Mn, Cu, Co, Se, Hg, Ag, and Pb.

  18. Separation and characterization of magnetic fractions from waste-to-energy bottom ash with an emphasis on the leachability of heavy metals.

    Science.gov (United States)

    Wei, Yunmei; Mei, Xiaoxia; Shi, Dezhi; Liu, Guotao; Li, Li; Shimaoka, Takayuki

    2017-06-01

    Magnetic fractions were extracted from pulverized waste-to-energy (WTE) bottom ashes using a combined wet-dry extraction method. The resulting magnetic and non-magnetic fractions were subjected to compositional, mineralogical, and redox state analyses by X-ray diffraction (XRD), X-ray fluorescence, and X-ray photoelectron spectroscopy (XPS), respectively. The distribution and leaching toxicity of heavy metals were assessed to evaluate potential effects on the environment. Compositional analyses revealed that Fe accounted for 35% of the magnetic fraction of pulverized ashes, which was approximately seven times that of the raw ash. In addition to Fe, elemental Ni, Mn, and Cr were also significantly enriched in the magnetic fractions. The mineralogical analysis determined that Fe was primarily present as hematite and magnetite, and metallic iron was also identified in the magnetic fraction samples. The XPS analysis further proved the existence of zero-valence Fe. However, a significant amount of Fe remained in the non-magnetic fractions, which could partially be ascribed to the intergrowth structure of the various minerals. The elevated concentrations of toxicity characteristic leaching procedure (TCLP)-extracted Mn, Ni, Cr, Cu, Pb, and Zn were primarily ascribed to the lower buffering capability of the magnetic fractions, with the enrichment of Mn, Ni, and Cr in the magnetic fractions also contributing to this elevation.

  19. Chemical and radiological characterization of fly and bottom ash landfill of the former sulfate pulp factory Plaški and its surroundings.

    Science.gov (United States)

    Oreščanin, Višnja; Kollar, Robert; Buben, Kresimir; Mikelic, Ivanka Lovrencic; Kollar, Karlo; Kollar, Melkior; Medunic, Gordana

    2012-01-01

    The subject of this study was chemical and radiological characterization of the fly and bottom ash, by-product of the combustion of coal used as an energy source in the former sulfate pulp factory in Plaški. The research involves determination of the concentration of macro, micro and trace elements and activities of the radionuclides in: (i) ash from different positions of the landfill; (ii) soil samples in the zone of the influence of the landfill; (iii) control soil samples and (iv) sediment sample from the river Dretulja. Besides, in situ measurement of an effective dose rate above ash/soil was also determined. In relation with the control soil the average increase of the concentrations of the elements Ca, Cd, Hg, Ni, Se, Sr, Th and U in the samples taken from the fly and bottom ash landfill as well as soil samples within the radius of 300 m from the landfill was 38.3, 6.7, 9.9, 8.5, 9.4, 7.2, 3.6 and 5.7 times, respectively. In these samples, the concentrations of the above mentioned elements were in the following ranges: calcium from 7.94 to 19.7 %; cadmium from 0.33 to 1.66 mg/kg; mercury from 0.18 to 0.49 mg/kg; nickel from 260 to 1500 mg/kg; selenium from 2.7 to 21 mg/kg; strontium from 176 to 542 mg/kg; thorium from 8 to 55 mg/kg and uranium from 5.6 to 19.7 mg/kg. Compared to the world's average soil concentration, uranium and thorium values increased 3.7 and 1.7 times, respectively. The mean value of the total effective dose rate measured in the air at the height of 1 m for all samples of ash and soil under the influence of the landfill was 1.60 mSv/yr. Compared to the Croatian average (0.7015 mSv/yr), the determined mean value for the Plaški landfill is two times higher. However, compared to the local background (0.14 mSv/yr), the mean value of the total effective dose rate measured above the Plaški landfill is 11.4 times higher. In the samples of ash and contaminated soil regardless of the sampling location the activity concentrations of the

  20. Experience of the environmental impact in the use of MSWI bottom ash as subbase layer; Erfarenheter av miljoepaaverkan vid anvaendning av slaggrus som foerstaerkningslager

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, Peter

    2008-12-15

    This report presents an evaluation of the environmental impact that the use of MSWI bottom ash as a subbase layer in asphalt parking spaces and drives can cause. The focus has been on the migration of mobile ions such as salts (chloride and sulfate), because these substances can be used as early indicators of the migration of contaminants. The results can be seen as a conservative assessment of other types of substances which are less soluble and mobile. The background of the project was that the Malmoe City Environmental Department wanted an evaluation of the environmental impact caused by the use of bottom ash in the area of Svaagertorp, just south of Malmoe urban area, because elevated levels of chloride and sulfate in water samples from several ground water pipes were found. In response to this request, Sysav Utveckling initiated a project to assess the environmental impact of the current object. At Svaagertorp, bottom ash has been used to build a number of parking spaces and drives. A relatively large amount of bottom ash (approximately 40 000 tons) have been used. The aim of the project was to investigate the environmental impacts of the use of bottom ash in construction projects. To achieve this objective, the project should describe and evaluate the importance of various sources of pollution (the source term) describe the mechanisms that control the migration of contaminants in the area describe the local environmental impact. The evaluation of the environmental consequences was based on a synthesis of several different field studies and analysis; resistivity soundings with cpt-probe, surface resistivity measurements with a measuring system of the type ABDEM Lund Imaging System, analysis of surface and ground water samples and analysis of soil samples and soil profiles. Numerical modeling of two simplified scenarios was used to support the interpretations of the results from field surveys. Environmental impacts at Svaagertorp The overall assessment within

  1. Study on the feasibility of municipal solid waste incineration bottom ash reutilization%城市垃圾焚烧底灰资源化处理的可行性研究

    Institute of Scientific and Technical Information of China (English)

    胡艳军; 李国建; 宁方勇; 任建莉

    2011-01-01

    对天津某城市垃圾焚烧发电厂的垃圾焚烧底灰进行采样,测试评价了不同粒径焚烧底灰的工程特性及环境风险,并以焚烧底灰为骨料制备混凝土平板试件,分析了焚烧底灰中杂质组分对再生建筑材料的工程特性影响.研究发现,焚烧底灰的颗粒级配分布、主要元素成分及含量、砂当量、压实强度与天然建筑骨料相似,且不同粒径的焚烧底灰在使用过程中无毒性重金属浸出危害.但焚烧底灰作为建筑材料使用过程中,易出现裂缝等质量损伤状况,从焚烧底灰自身特性和其中的杂质组分在碱性环境下变化规律着手,分析了再生建筑材料产生损伤的可能原因,提出改善焚烧底灰工程性能的措施.%The municipal solid waste incineration (MSWI) bottom ash was sampled in Tianjin MSW incineration power plant to investigate the engineering and environmental properties of different sized bottom ash. The MSWI bottom ash was applied as aggregate to prepare construction stick specimen, and possible influences of the special components contained in bottom ash on engineering properties of the recycled construction material were analyzed. The results showed that MSWI bottom ash had similar properties to natural construction aggregates, such as particle size distribution, major elements and theirconcentrations, sand equivalent, compaction density. Meanwhile, reutilization of the bottom ash was friendly to environment. However, a few cracks in the construction stick specimen were found during testing period. The factors influencing the cracks in the stick was analyzed in terms of the specific components of the bottom ash and other physical properties. Finally, method and technology of improving the properties of the recycled bottom ash aggregate were proposed.

  2. FINANCIAL PROBLEMS OF BOTTOM 40 PERCENT BUMIPUTERA IN MALAYSIA: A POSSIBLE SOLUTION THROUGH WAQF-BASED CROWDFUNDING

    Directory of Open Access Journals (Sweden)

    Abidullah ABID

    2017-02-01

    Full Text Available Low savings by the bottom 40 percent Bumiputera triggered low wealth accumulation and greater wealth inequality. The issue behind the low savings is the increase in food prices, taxes, and interest rates for the borrowers. In response to these problems, the Malaysian government provides cash transfer BRIM as one of redistributive measures. However, it is still not enough as many of the bottom 40 percent are neglected to avail the facility. In such circumstances, the role of community-based cash and credit transfer schemes such as cash waqf can be more fruitful. However due to inefficiency of the awqaf institutions regarding financial management, the system cannot contribute effectively. Therefore, the main aim of the paper is to provide an efficient mechanism which can ensure effectiveness in terms of transparency, collection and distribution of cash endowments and its benefits. Hence, by means of library research, we have proposed a conceptual framework. It is suggested that collection and distribution of cash waqf through crowdfunding platform would solve both transparency, collection and distribution issues. This study would provide a ground for those researchers and practitioners who are working on finding the right approach to implement waqf in more efficient way.

  3. INTRINSIC FACTORS AND FIRM FINANCIAL ANALYSIS WITH TRIPPLE BOTTOM LINES AS INTERVENING VARIABLE AGAINST FIRM VALUE Empirical Studies on Property and Real Estate Companies Year 2010-2013

    OpenAIRE

    Sari, Mia Andika; Wiralaga, Harya Kuncara; Warokka, Ari

    2016-01-01

    This research conducted to examine the influence of intrinsic factors which being proxied with Capital Structure, Firm Size, Firm Age and Financial factors that being proxied with liquidity, profitability also with another activities using tripple bottom lines as Intervening Variable against Firm Value of Property Industries. The data that being used in this study were obtained from published financial statements during the period 2010 to 2013, as well as annual reports that can be accessed t...

  4. Heavy metal leaching from aerobic and anaerobic landfill bioreactors of co-disposed municipal solid waste incineration bottom ash and shredded low-organic residues.

    Science.gov (United States)

    Inanc, Bulent; Inoue, Yuzo; Yamada, Masato; Ono, Yusaku; Nagamori, Masanao

    2007-03-22

    In this study, heavy metal leaching from aerobic and anaerobic landfill bioreactor test cells for co-disposed municipal solid waste incineration (MSWI) bottom ash and shredded low-organic residues has been investigated. Test cells were operated for 1 year. Heavy metals which were comparatively higher in leachate of aerobic cell were copper (Cu), lead (Pb), boron (B), zinc (Zn), manganese (Mn) and iron (Fe), and those apparently lower were aluminum (Al), arsenic (As), molybdenum (Mo), and vanadium (V). However, no significant release of heavy metals under aerobic conditions was observed compared to anaerobic and control cells. Furthermore, there was no meaningful correlation between oxidation-reduction potential (ORP) and heavy metal concentrations in the leachates although some researchers speculate that aeration may result in excessive heavy metal leaching. No meaningful correlation between dissolved organic carbon (DOC) and leaching of Cu and Pb was another interesting observation. The only heavy metal that exceeded the state discharge limits (10mg/l, to be enforced after April 2005) in the aerobic cell leachate samples was boron and there was no correlation between boron leaching and ORP. Higher B levels in aerobic cell should be due to comparatively lower pH values in this cell. However, it is anticipated that this slightly increased concentrations of B (maximum 25mg/l) will not create a risk for bioreactor operation; rather it should be beneficial for long-term stability of the landfill through faster washout. It was concluded that aerobization of landfills of heavy metal rich MSWI bottom ash and shredded residues is possible with no dramatic increase in heavy metals in the leachate.

  5. Experimental Studies and Application of a Composite Fluidized Bed Bottom Ash Cooler%复合式流化床冷渣器的试验研究及工业应用

    Institute of Scientific and Technical Information of China (English)

    曾兵; 卢啸风; 赵鹏; 甘露; 舒茂龙

    2011-01-01

    A novel fluidized bed bottom ash cooler and the main technical characteristics are introduced. Experiments about gas-solid flow characteristics were conducted in a cold test bed. The experiment results show that the separation chamber has a good separation effect on the boiler bottom ash, and the ash flow characteristic is also good. The separation effect has a direct influence on the operation results of the new ash cooler and can be regulated by adjusting the operation and structure parameters. According to the experiment results, the composite fluidized bed bottom ash cooler (CFBAC) has been industrially applied in a 300MW circulating fluidized bed (CFB) unitl The application results show that the CFBAC has a good cooling effect of bottom ash, a well separation effect, an excellent adaptability on particle size and a large discharge capacity over 30 t/h. The CFBAC could be one direction of the future CFB boiler bottom ash cooler.%提出一种新型流化床冷渣器,介绍了其主要技术特点,并对其气固流动特性进行冷态试验研究。试验结果表明,分选仓喷动床结构对锅炉底渣的粗细颗粒分选作用相当明显,灰渣颗粒整体呈“溢流一底流一溢流”方式有较好的流动特性。分选仓分选效果直接决定着该冷渣器的运行效果,可以通过调节运行参数和结构参数来控制。根据试验结果设计的复合式流化床冷渣器已成功应用于某300Mw循环流化床机组冷渣器改造中。工业应用结果表明,该冷渣器具有较好的底渣冷却效果和粗细颗粒分选效果,底渣粒度适应性强,最大出力超过30讹。复合式流化床冷渣器可作为未来大型循环流化床锅炉冷渣器的发展方向之一。

  6. 垃圾焚烧炉渣活性激发及对水泥性能的影响%Stimulation of MSWI Bottom Ash Activity and Effects on Cement Performance

    Institute of Scientific and Technical Information of China (English)

    李相国; 宋留庆; 马保国; 方晨炜; 汪杰

    2012-01-01

    The author studied properties of cement that partially replaced by MWIS bottom ash as a cement admixture, and investigated slag cement' s activity of stimulating and environmental safety. The results show that: MWIS bottom ash is of weak activity, with bottom ash replaces cement increases, water for cement standard consistency slowly increased, setting time slightly extended, but has little effect on cement strength reduced. The dosage of MWIS bottom ash in PO 42.5 cement even reached 25 %. PO 32. 5 cement production requirements can be satisfied. In the aspects of stimulating the activity, the added of Ca-based activators into cement can improve the early and late strength (CaCl2 will result in late strength's retraction), Conversely, Na-based activators will reduce the intensity. MWIS bottom ash as cement admixture reduces the shrinkage of cement paste. MWIS bottom ash dosage of 35%, the mortar test block dissolution of heavy metal content is much lower than the limit of maximum allowable concentration of national standard and will not bring secondary pollution to the environment%通过外掺法研究了城市生活垃圾焚烧炉渣用作水泥混合材对水泥性能的影响,同时考察了炉渣活性激发和炉渣水泥的环境安全性.实验结果表明:炉渣具有较弱的火山灰活性,随着其掺入量的增加,水泥标准稠度用水量增加,凝结时间延长,水泥强度下降,当PO 42.5水泥中炉渣掺量达到25%时仍能达到PO 32.5水泥生产要求.在炉渣活性激发方面,钙系列激发剂能够提高炉渣水泥的早期和后期强度(CaCl2会使后期强度倒缩),钠系列激发剂均会降低其强度.炉渣的掺入能够降低水泥净浆化学收缩率.在炉渣掺量35%时,砂浆试块的重金属极限溶出含量远低于国家标准最高允许浓度,不会对环境带来二次污染.

  7. Sustainable High Quality Recycling of Aggregates from Waste-to-Energy, Treated in a Wet Bottom Ash Processing Installation, for Use in Concrete Products

    Directory of Open Access Journals (Sweden)

    Philip Van den Heede

    2015-12-01

    Full Text Available Nowadays, more efforts towards sustainability are required from the concrete industry. Replacing traditional aggregates by recycled bottom ash (BA from municipal solid waste incineration can contribute to this goal. Until now, only partial replacement has been considered to keep the concrete workability, strength and durability under control. In this research, the feasibility of a full aggregate replacement was investigated for producing prefabricated Lego bricks. It was found that the required compressive strength class for this purpose (C20/25 could be achieved. Nevertheless, a thorough understanding of the BA properties is needed to overcome other issues. As BA is highly absorptive, the concrete’s water demand is high. This workability issue can be dealt with by subjecting the fine BA fraction to a crushing operation to eliminate the porous elements and by pre-wetting the fine and coarse BA fractions in a controlled manner. In addition, a reactive NaOH washing is needed to avoid formation of longitudinal voids and the resulting expansion due to the metallic aluminum present in the BA. Regarding the long-term behavior, heavy metal leaching and freeze-thaw exposure are not problematic, though there is susceptibility to acetic and lactic acid attack and maybe increased sensitivity to alkali-silica reaction.

  8. 垃圾焚烧底渣中重金属的研究%Study on heavy metals in solid waste incineration bottom ash

    Institute of Scientific and Technical Information of China (English)

    徐朝友; 梅凡民; 刘翠

    2011-01-01

    采用Tessier四步分级提取法对垃圾焚烧飞灰中的4种重金属(锌、镍、铜、镉)的化学形态进行了研究.结果表明,金属Cd主要以底渣态的形式存在(占总镉质量的61.22%~62.41%),Ni,Zn以底渣态和铁锰氧化态为主,Cu主要以有机结合态为主(占总铜质量的60.97%~62.29 %).同时4种金属的生物有效性由高到低顺序依次为Ni,Cd,Zn,Cu.%The 4 heavy metals (Zn, Ni, Cu, Cd) in solid waste incineration bottom ash are studied by Four-step sequential chemical extraction method of Tessier. The results show that metal Cd mainly exists in residual fraction (account for 61.22% to 62.41 % of the total mass of cadmium), metal Ni and Zn mainly exists in residual fraction and Fe-Mn oxide fraction, metal Cu mainly exists in organic fraction (account for 60. 97% to 62.29% of the total mass of copper). The bioavailability of four heavy metals from high to low is Ni, Cd, Zn, Cu.

  9. Sustainable High Quality Recycling of Aggregates from Waste-to-Energy, Treated in a Wet Bottom Ash Processing Installation, for Use in Concrete Products

    Science.gov (United States)

    Van den Heede, Philip; Ringoot, Niels; Beirnaert, Arno; Van Brecht, Andres; Van den Brande, Erwin; De Schutter, Geert; De Belie, Nele

    2015-01-01

    Nowadays, more efforts towards sustainability are required from the concrete industry. Replacing traditional aggregates by recycled bottom ash (BA) from municipal solid waste incineration can contribute to this goal. Until now, only partial replacement has been considered to keep the concrete workability, strength and durability under control. In this research, the feasibility of a full aggregate replacement was investigated for producing prefabricated Lego bricks. It was found that the required compressive strength class for this purpose (C20/25) could be achieved. Nevertheless, a thorough understanding of the BA properties is needed to overcome other issues. As BA is highly absorptive, the concrete’s water demand is high. This workability issue can be dealt with by subjecting the fine BA fraction to a crushing operation to eliminate the porous elements and by pre-wetting the fine and coarse BA fractions in a controlled manner. In addition, a reactive NaOH washing is needed to avoid formation of longitudinal voids and the resulting expansion due to the metallic aluminum present in the BA. Regarding the long-term behavior, heavy metal leaching and freeze-thaw exposure are not problematic, though there is susceptibility to acetic and lactic acid attack and maybe increased sensitivity to alkali-silica reaction. PMID:28787809

  10. Model simulations for describing water transport in a landfill with bottom ash from a municipal solid waste incinerator (MSWI): model validation and scenarios.

    Science.gov (United States)

    Hartmann, Frank; Bader, Hans-Peter; Scheidegger, Ruth

    2004-10-01

    In the present study the water movement in a bottom ash landfill from a municipal solid waste incinerator (MSWI) was investigated. The pore regime of such landfills consists of macropores (with diameter > 50 microm), which make up about two-thirds of the total porosity and micropores. The program MACRO, which describes flow through porous media and takes both macro- and micropore flows into account, was applied. The model was calibrated with a time series from the landfill Riet, near Winterthur in Switzerland. In the present study the model was recalibrated at a time series for 1 year. With this scenario the influence of an expected reduction or increase of the porosity on leachate behaviour of such landfills over a long time (> 100 years) was studied ('long-term behaviour'). It has been shown that reliable information about water percolation can only be provided by obtaining more information about the hydraulic structure of such landfills. In particular, the number of macropores and the porosity exert great influence on the water movement.

  11. The rare earth elements in municipal solid waste incinerators ash and promising tools for their prospecting

    Energy Technology Data Exchange (ETDEWEB)

    Funari, Valerio, E-mail: valerio.funari@unibo.it [Dipartimento di Scienze Biologiche, Geologiche e Ambientali (BiGeA)—University of Bologna, Piazza di Porta San Donato 1, Bologna (Italy); Bokhari, Syed Nadeem Hussain [General and Analytical Chemistry—Montanuniversität Leoben, Franz-Josef-Str. 18, Leoben (Austria); Vigliotti, Luigi [Istituto di Scienze Marine (ISMAR-CNR)—National Research Council, Via Piero Gobetti 101, Bologna (Italy); Meisel, Thomas [General and Analytical Chemistry—Montanuniversität Leoben, Franz-Josef-Str. 18, Leoben (Austria); Braga, Roberto [Dipartimento di Scienze Biologiche, Geologiche e Ambientali (BiGeA)—University of Bologna, Piazza di Porta San Donato 1, Bologna (Italy)

    2016-01-15

    Highlights: • The REE concentrations of bottom and fly ashes from municipal incinerators are investigated. • First attempt toward discriminating the magnetic signature (susceptibility) of ashes from incinerators. • New methods and parameters for REE prospecting, which can be determined quickly and with limited costs, are provided. - Abstract: Bottom and fly ashes from Municipal Solid Waste Incinerators (MSWI) are hazardous products that present concern for their safe management. An attractive option to reduce their impact both on the environment and the financial commitment is turning MSWI ashes into secondary raw materials. In this study we present the REE content and distribution of bottom and fly ashes from MSWI after a highly effective digestion method and samples analysis by ICP–MS. The chondrite-normalised REE patterns of MSWI bottom and fly ash are comparable with that of crustal averages, suggesting a main geogenic source. Deviations from typical crustal pattern (e.g., Eu, Tb) disclose a contribution of likely anthropogenic provenance. The correlation with major elements indicates possible sources for REE and facilitates a preliminary resource assessment. Moreover, magnetic susceptibility measurements can be a useful prospecting method in urban ores made of MSWI ashes. The relationship between REE and some influencing parameters (e.g., Pricing Influence Factor) emphasises the importance of MSWI ash as alternative source of REE and the need of further efforts for REE recovery and purification from low concentrations but high flows waste.

  12. Analysis and Improvement of Problems in Operation of Bottom Ash Cooler of Wind and Water Union%风水联合冷渣器在运行中的问题分析及改进

    Institute of Scientific and Technical Information of China (English)

    王凯; 胡娜娜

    2013-01-01

      风水联合冷渣器广泛应用于大型循环流化床锅炉,但在运行中出现了诸多问题。针对某电厂风水联合冷渣器在运行中出现的问题,提出了改进措施与建议。%Bottom ash cooler of wind and water union was widely used in large-scale circulating fluidized bed boiler. Howev-er, there were many problems in operation. Aiming at problems in operation of bottom ash cooler of wind and water union, the paper was put forward improving measures and suggestions.

  13. 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.

  14. Influence of bacteria on lanthanide and actinide transfer from specific soil components (humus, soil minerals and vitrified municipal solid waste incinerator bottom ash) to corn plants: Sr-Nd isotope evidence

    Energy Technology Data Exchange (ETDEWEB)

    Aouad, Georges [Ecole et Observatoire des Sciences de la Terre, Centre de Geochimie de la Surface/CNRS UMR 7517, 1 rue Blessig, 67084 Strasbourg Cedex (France); Stille, Peter [Ecole et Observatoire des Sciences de la Terre, Centre de Geochimie de la Surface/CNRS UMR 7517, 1 rue Blessig, 67084 Strasbourg Cedex (France)]. E-mail: pstille@illite.u-strasbg.fr; Crovisier, Jean-Louis [Ecole et Observatoire des Sciences de la Terre, Centre de Geochimie de la Surface/CNRS UMR 7517, 1 rue Blessig, 67084 Strasbourg Cedex (France); Geoffroy, Valerie A. [UMR 7156 Universite Louis-Pasteur/CNRS, Genetique Moleculaire, Genomique Microbiologie, Departement Micro-organisme, Genomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex (France); Meyer, Jean-Marie [UMR 7156 Universite Louis-Pasteur/CNRS, Genetique Moleculaire, Genomique Microbiologie, Departement Micro-organisme, Genomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex (France); Lahd-Geagea, Majdi [Ecole et Observatoire des Sciences de la Terre, Centre de Geochimie de la Surface/CNRS UMR 7517, 1 rue Blessig, 67084 Strasbourg Cedex (France)

    2006-11-01

    Experiments have been performed to test the stability of vitrified municipal solid waste (MSW) incinerator bottom ash under the presence of bacteria (Pseudomonas aeruginosa) and plants (corn). The substratum used for the plant growth was a humus-rich soil mixed with vitrified waste. For the first time, information on the stability of waste glasses in the presence of bacteria and plants is given. Results show that inoculated plant samples contained always about two times higher lanthanide and actinide element concentrations. Bacteria support the element transfer since plants growing in inoculated environment developed a smaller root system but have higher trace element concentrations. Compared with the substratum, plants are light rare earth element (LREE) enriched. The vitrified bottom ash has to some extent been corroded by bacteria and plant activities as indicated by the presence of Nd (REE) and Sr from the vitrified waste in the plants. {sup 87}Sr/{sup 86}Sr and {sup 143}Nd/{sup 144}Nd isotope ratios of plants and soil components allow the identification of the corroded soil components and confirm that bacteria accelerate the assimilation of elements from the vitrified bottom ash. These findings are of importance for landfill disposal scenarios, and similar experiments should be performed in order to better constrain the processes of microbially mediated alteration of the MSW glasses in the biosphere.

  15. 干式排渣在大型电站锅炉上的运行特性分析%Operating Characteristic Analysis of Dry Bottom Ash Handling System on Power Station Boiler

    Institute of Scientific and Technical Information of China (English)

    董信光; 李洪涛; 冷成岗; 李德功

    2012-01-01

    Comparing to the discharging slag by water, the dry bottom ash handling system has many advantages such as simple structure, water conserving, more useful. When the bottom ash system has been changed from water mode to dry mode, the operating characteristics of boiler will be varied, which is analyzed and optimized in detailed. Positive and negative impacts are found, which can be referred when the bottom ash system revised and boiler operating.%和水力除渣方式相比,干式排渣有结构简单、节水、干渣经济价值高等优点。将原水力除渣改为干式排渣后,锅炉的运行特性会发生变化,通过对干式排渣运行特性的全面分析和优化,找出积极因素和负面影响,为除渣系统的改造和运行提供参考。

  16. Influence of bacteria on lanthanide and actinide transfer from specific soil components (humus, soil minerals and vitrified municipal solid waste incinerator bottom ash) to corn plants: Sr-Nd isotope evidence.

    Science.gov (United States)

    Aouad, Georges; Stille, Peter; Crovisier, Jean-Louis; Geoffroy, Valérie A; Meyer, Jean-Marie; Lahd-Geagea, Majdi

    2006-11-01

    Experiments have been performed to test the stability of vitrified municipal solid waste (MSW) incinerator bottom ash under the presence of bacteria (Pseudomonas aeruginosa) and plants (corn). The substratum used for the plant growth was a humus-rich soil mixed with vitrified waste. For the first time, information on the stability of waste glasses in the presence of bacteria and plants is given. Results show that inoculated plant samples contained always about two times higher lanthanide and actinide element concentrations. Bacteria support the element transfer since plants growing in inoculated environment developed a smaller root system but have higher trace element concentrations. Compared with the substratum, plants are light rare earth element (LREE) enriched. The vitrified bottom ash has to some extent been corroded by bacteria and plant activities as indicated by the presence of Nd (REE) and Sr from the vitrified waste in the plants. (87)Sr/(86)Sr and (143)Nd/(144)Nd isotope ratios of plants and soil components allow the identification of the corroded soil components and confirm that bacteria accelerate the assimilation of elements from the vitrified bottom ash. These findings are of importance for landfill disposal scenarios, and similar experiments should be performed in order to better constrain the processes of microbially mediated alteration of the MSW glasses in the biosphere.

  17. Characteristics of fly ash and bottom ash from the municipal solid waste incineration plant in Shanghai%上海地区生活垃圾焚烧灰渣元素组成及微观特征研究

    Institute of Scientific and Technical Information of China (English)

    曹玲玲; 刘可; 曾建荣; 龙时磊; 包良满; 马陈燕; 李燕

    2014-01-01

    利用同步辐射X射线荧光法(Synchrotron radiation X-ray fluorescence,SR-XRF)、离子色谱(Ion Chromatography,IC)、扫描电镜及其能谱分析(Scanning electron microscopy and X-ray energy dispersive microanalysis,SEM-EDX)、同步辐射微束X射线荧光法(Synchrotron radiation micro-beam X-ray fluorescence,μ-XRF)等手段研究上海某垃圾焚烧厂生活垃圾焚烧产物飞灰(Fly ash,FA)、炉渣(Bottom ash,BA)的元素浓度、离子组成、微观形貌、元素面分布,采用电感耦合等离子体质谱(Inductively Coupled Plasma Mass Spectrometry,ICP-MS)和X射线吸收精细结构谱(X-ray absorption near-edge structure,XANES)研究灰渣中Pb的同位素比值和化学种态.研究发现,飞灰中多数金属元素浓度高于炉渣中的,Pb、Cd明显富集于飞灰中,元素的富集因子显示Pb、Cd、Cu、Zn等呈极度污染状态.灰渣中水溶性成分主要为Ca、Na、K的氯化盐和硫酸盐,飞灰中离子浓度普遍高于炉渣中的.飞灰颗粒相对于炉渣颗粒粒径小、表面粗糙,更易于重金属的吸附.灰渣颗粒物的元素Pb、Zn、Cu、Cr、Fe、Mn等并不是均匀分布的,而是呈现局部明显富集.飞灰和炉渣Pb的来源相似,化学种态相似,主要为PbCl2、PbS和PbO.生活垃圾在焚烧过程中元素的迁移分布与元素本身的特性、焚烧环境相关,上海地区生活垃圾焚烧飞灰是危险废弃物,需稳定化处理后才能填埋,炉渣的资源化利用必需经过预处理.

  18. Characterisation of major component leaching and buffering capacity of RDF incineration and gasification bottom ash in relation to reuse or disposal scenarios.

    Science.gov (United States)

    Rocca, Stefania; van Zomeren, André; Costa, Giulia; Dijkstra, Joris J; Comans, Rob N J; Lombardi, Francesco

    2012-04-01

    Thermal treatment of refuse derived fuel (RDF) in waste-to-energy (WtE) plants is considered a promising solution to reduce waste volumes for disposal, while improving material and energy recovery from waste. Incineration is commonly applied for the energetic valorisation of RDF, although RDF gasification has also gained acceptance in recent years. In this study we focused on the environmental properties of bottom ash (BA) from an RDF incineration (RDF-I, operating temperature 850-1000°C) and a RDF gasification plant (RDF-G, operating temperature 1200-1400°C), by evaluating the total composition, mineralogy, buffering capacity, leaching behaviour (both at the material's own pH and as a function of pH) of both types of slag. In addition, buffering capacity results and pH-dependence leaching concentrations of major components obtained for both types of BA were analysed by geochemical modelling. Experimental results showed that the total content of major components for the two types of BA was fairly similar and possibly related to the characteristics of the RDF feedstock. However, significant differences in the contents of trace metals and salts were observed for the two BA samples as a result of the different operating conditions (i.e. temperature) adopted by the two RDF thermal treatment plants. Mineralogy analysis showed in fact that the RDF-I slag consisted of an assemblage of several crystalline phases while the RDF-G slag was mainly made up by amorphous glassy phases. The leached concentrations of major components (e.g. Ca, Si) at the natural pH of each type of slag did not reflect their total contents as a result of the partial solubility of the minerals in which these components were chemically bound. In addition, comparison of total contents with leached concentrations of minor elements (e.g. Pb, Cu) showed no obvious relationship for the two types of BA. According to the compliance leaching test results, the RDF-G BA would meet the limits of the Italian

  19. 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

  20. Hydrological and geochemical factors affecting leachate composition in municipal solid waste incinerator bottom ash. Part I: The hydrology of Landfill Lostorf, Switzerland

    Science.gov (United States)

    Johnson, C. Annette; Richner, Gérald A.; Vitvar, Tomas; Schittli, Nina; Eberhard, Mark

    1998-10-01

    The objective of the investigation of the municipal solid waste incinerator (MSWI) bottom ash landfill, Landfill Lostorf, was to determine the residence time of water in the landfill and the flow paths through the landfill. Over a period of 22 months, measurements of rainfall, landfill discharge and leachate electrical conductivity were recorded and tracer experiments made. Over the yearly period 1995, approximately 50% of the incident rainfall was measured in the discharge. An analysis of single rain events showed that in winter, 90-100% of rainfall was expressed in the landfill discharge, whereas in summer months, the value was between 9 and 40% depending on the intensity of the rain event. The response to rainfall was rapid. Within 30-100 h, approximately 50% of water discharged in response to a rain event had left the landfill. The discharge was less than 4 l/min for approximately 50% of the measurement periods. Qualitative tracer studies with fluorescein, pyranine and iodide clearly showed the existence of preferential flow paths. This was further substantiated by quantitative tracer studies of single rain events using 18O/ 16O ratios and electrical conductivity measurements. The proportion of rainwater passing directly through the landfill was found to be between 20 and 80% in summer months and around 10% in winter months. The difference has been ascribed to the water content in the landfill. The average residence time of the water within the landfill has been estimated to be roughly 3 years and this water is the predominant component in the discharge over a yearly period.

  1. Impact of co-landfill proportion of bottom ash and municipal solid waste composition on the leachate characteristics during the acidogenesis phase.

    Science.gov (United States)

    He, Pin-Jing; Pu, Hong-Xia; Shao, Li-Ming; Zhang, Hua

    2017-08-14

    Incineration has become an important municipal solid waste (MSW) treatment strategy, and generates a large amount of bottom ash (BA). Although some BA is reused, much BA and pretreatment residues from BA recycling are disposed in landfill. When BA and MSW are co-landfilled together, acid neutralization capacity and alkaline earth metal dissolution of BA, as well as different components of MSW may change environmental conditions within the landfill, so the degradation of organic matter and the physical and chemical properties of leachate would be affected. In this study, the effect of co-landfilled BA and MSW on the leachate characteristics during the hydrolysis and acidogenesis phase was studied using different BA/MSW ratios and MSW compositions. The results showed that the co-landfill system increased leachate pH, electric conductivity and alkalinity. For MSW with a high content of degradable components, the release and degradation of total organic carbon (TOC) and volatile fatty acids (VFA) from MSW were promoted when the BA ratio by wet weight was less than 50%, and the biodegradability of leachate was improved. When the BA ratio exceeded 50%, the degradation of organic matters was inhibited. For MSW with low content of degradable components, when the proportion of BA was less than 20%, the release and degradation of TOC and VFA from MSW were promoted and alkalinity increased. When the BA ratio exceeded 20%, the degradation of organic matters was inhibited. The 50% BA ratio could improve the bio-treatability of leachate indicated by the leachate pH and C/N ratio. However, BA inhibited the release of nitrogen (TN and NH4(+)-N) at all BA ratios and MSW compositions. At the same time, the addition of BA increased the risk of leachate collection system clogging due to the dissolution and re-precipitation of alkaline earth metals contained in BA. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. The Vaendoera test road, Sweden: A case study of long-term properties of roads constructed with MSWI bottom ash; Projekt Vaendoera: En studie av laangtidsegenskaper hos vaegar anlagda med bottenaska fraan avfallsfoerbraenning

    Energy Technology Data Exchange (ETDEWEB)

    Bendz, David; Arm, Maria; Westberg, Gunnar; Sjoestrand, Karin; Lyth, Martin; Wik, Ola [Swedish Geotechnical Inst., Linkoeping (Sweden); Flyhammar, Peter [Lund Inst. of Technology (Sweden). Dept. of Water Resources Engineering

    2006-03-15

    The accumulated effects of leaching and aging in a subbase layer of bottom ash were investigated in this study. The paved test road were constructed in 1987 in Linkoeping, Sweden, and has been used until the start of this study. The objective of this study was to investigate: (i) the accumulated effects of leaching and aging (ii) the accumulated effects of load and aging on the geotechnical properties (iii) the prerequisites for separate excavation of the bottom ash for possible reuse. The study started in September 2003 and included tests with falling weight deflectometer, triax testing on undisturbed core samples of bottom ash, sampling for chemical analysis. Three trenches were excavated in the test road, samples of the subbase layer and the subgrade were taken in the shaft walls and brought to the laboratory for leaching tests (EN 12457-2) and extraction, respectively. The extraction procedure was used to estimate extractable and chemically available fractions. It was found that the steady increase of stiffness which had been detected by falling weight deflectometer during the first years after construction had ceased. The undisturbed samples showed stiffness comparable with recently produced bottom ash from the same incineration plant, but lower stiffness if compared with the reference material of crushed rock. The permanent deformation was significantly larger for the samples compared with the crushed rock and recent (1999-2001) bottom ash from other incineration plants. The spatial distribution patterns of leachable easily soluble constituents reveal the existence of horizontal gradients, directed from the center of the road towards the shoulders of the road. This implies that horizontal transport by diffusion is the rate limiting leaching process for all easily soluble constituents underneath the pavement in a road. The bottom ash that was used in the sub-base layer was fresh at the time of the construction of the test road with a pH of about 11. Measured p

  3. Application of the electrical characterization to the study of the hydrated phases of the cement with coal bottom ash; Aplicacion de la caracterizacion electrica al estudio de las fases hidratadas de cemento con adicion de escorias de centrales termicas

    Energy Technology Data Exchange (ETDEWEB)

    Menendez, E.; Frutos, J. de; Alvaro, A. M.

    2014-02-01

    The present paper investigates the influence of using Bottom and Fly Ash as partial replacement of cement in the hydration process. Through measurements of electrical impedance spectroscopy (EIS) and X -ray diffraction (XRD), we analyze from the early stages to the hydration process to the end. Values of EIS, XRD and its relation, are used to determine transformation of hydrated phases, and for each of the substitutions, is indicated as modified the hydrated phase as a function of time and compared it with the reference material. It also proves the relevance of using EIS measures in real time, and as non destructive testing to characterize the hydration process of these materials. (Author)

  4. Physicochemical Properties and Recycling Technology of Bottom Ash of Sewage Sludge Incineration%污泥焚烧底灰的理化性质及再利用技术

    Institute of Scientific and Technical Information of China (English)

    王少波; 贾廷纲; 缪幸福; 米琼; 刘大江; 赵由才

    2014-01-01

    The problem of disposal and utilization of bottom ash of sewage sludge incineration in sludge incineration process must be solved. In this paper,the physicochemical properties in terms of particle size,shear,compression consolidation,permeability,heavy metals content of two different kinds of bottom ash of sewage sludge incineration were studied and compared with the original sewage sludge properties to analyze the effect of incineration on sewage sludge treatment. The reuse technology of bottom ash of sewage sludge incineration was also explored based on its physicochemical properties. The results show that bottom ash of sewage sludge incineration belongs to sandy soil,and the shear strength significantly increases after the incineration,which can reach 76. 23 ~80. 03 kPa;the heavy metal content is over standard,while the heavy metal leaching amount is less than the corresponding standard limit. It can be used in subgrade materials,CO2 capture and sea reclamation.%污泥焚烧底灰的处理处置与资源化利用是污泥焚烧过程中必须解决的难题。该文通过对两种不同的污泥焚烧底灰的粒径、抗剪、压缩固结性、渗透性以及重金属含量等理化性质进行了研究,并将其与原生污泥性质进行对比,分析焚烧处理对污泥理化性质的影响,并进一步根据焚烧底灰性质,探索其再利用途径。结果表明污泥焚烧底灰属于砂土,且抗剪强度较污泥焚烧前有明显增大,可达76.23~80.03 kPa;重金属含量有所超标,但重金属浸出量均小于相应标准限定值,可进行路基材料、CO2捕集、填海造陆等再利用。

  5. 干式排渣系统网条生产设备的研制%Development of Steel Net Strip Producing Equipment in Dry Bottom Ash Handling System

    Institute of Scientific and Technical Information of China (English)

    张培林

    2015-01-01

    Stainless steel net strip is the key components of dry bottom ash handling system,usually be cold manufactured by the stainless steel wire of the greater tensile strength,the process is complex,the forming is difficult and in the same time,there is not the professional production equipment interiorly for manufacturing such products.We developed the net strip winding machine for the engineering demand of dry bottom ash handling system.The net strip product,manufactured through this equipment,has been well validated in engineering practice,this equipment fill a domestic gap in the field,with the great value of development and application.%网条是干式排渣系统的关键零部件,通常采用抗拉强度较大的不锈钢丝冷加工而成,其加工工艺复杂,成形难度大,而目前国内尚无此类产品的专业生产设备.针对干式排渣系统的工程需求,研制了网条绕制机.该设备绕制的网条产品在工程实践中得到了很好的验证,填补了该领域的国内空白,具有广泛的应用与开发价值.

  6. Adsorption isotherms, kinetics and column operations for the removal of hazardous dye, Tartrazine from aqueous solutions using waste materials--Bottom Ash and De-Oiled Soya, as adsorbents.

    Science.gov (United States)

    Mittal, Alok; Mittal, Jyoti; Kurup, Lisha

    2006-08-25

    Adsorbents, Bottom Ash (a power plant waste) and De-Oiled Soya (an agricultural waste) exhibit good efficacy to adsorb a highly toxic dye, Tartrazine. Through the batch technique equilibrium uptake of the dye is observed at different concentrations, pH of the solution, dosage of adsorbents and sieve size of adsorbents. Langmuir and Freundlich adsorption isotherms are successfully employed on both the adsorbents and on the basis of these models the thermodynamic parameters are evaluated. Kinetic investigations reveal that more than 50% adsorption of dye is achieved in about 1h in both the cases, whereas, equilibrium establishment takes about 3-4h. The linear plots obtained in rate constant and mass transfer studies further confirm the applicability of first order rate expression and mass transfer model, respectively. The kinetic data treated to identify rate controlling step of the ongoing adsorption processes indicate that for both the systems, particle diffusion process is predominant at higher concentrations, while film diffusion takes place at lower concentrations. The column studies reveal that about 96% saturation of both the columns is attained during their exhaustion, while about 88 and 84% of the dye material is recovered by eluting dilute NaOH solution through exhausted Bottom Ash and De-Oiled Soya columns, respectively.

  7. Adsorption isotherms, kinetics and column operations for the removal of hazardous dye, Tartrazine from aqueous solutions using waste materials-Bottom Ash and De-Oiled Soya, as adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Alok [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal 462 007 (India)]. E-mail: aljymittal@yahoo.co.in; Mittal, Jyoti [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal 462 007 (India); Kurup, Lisha [Department of Applied Chemistry, Maulana Azad National Institute of Technology, Bhopal 462 007 (India)

    2006-08-25

    Adsorbents, Bottom Ash (a power plant waste) and De-Oiled Soya (an agricultural waste) exhibit good efficacy to adsorb a highly toxic dye, Tartrazine. Through the batch technique equilibrium uptake of the dye is observed at different concentrations, pH of the solution, dosage of adsorbents and sieve size of adsorbents. Langmuir and Freundlich adsorption isotherms are successfully employed on both the adsorbents and on the basis of these models the thermodynamic parameters are evaluated. Kinetic investigations reveal that more than 50% adsorption of dye is achieved in about 1 h in both the cases, whereas, equilibrium establishment takes about 3-4 h. The linear plots obtained in rate constant and mass transfer studies further confirm the applicability of first order rate expression and mass transfer model, respectively. The kinetic data treated to identify rate controlling step of the ongoing adsorption processes indicate that for both the systems, particle diffusion process is predominant at higher concentrations, while film diffusion takes place at lower concentrations. The column studies reveal that about 96% saturation of both the columns is attained during their exhaustion, while about 88 and 84% of the dye material is recovered by eluting dilute NaOH solution through exhausted Bottom Ash and De-Oiled Soya columns, respectively.

  8. Estudo do efeito da quantidade de óxido de ferro em cinzas pesadas de carvão mineral na obtenção de vitrocerâmicos Study of iron oxide quantity on bottom ashes from mineral coal to glass ceramic production

    Directory of Open Access Journals (Sweden)

    Cláudia Terezinha Kniess

    2002-11-01

    Full Text Available Bottom ash has been used as raw material to glass and glass ceramic production because it is a source of SiO2 and Al2O3. However, the high concentration of iron (about 10% wt. difficulty the control of the nucleation and the crystallization processes. The iron content was reduced by magnetic process, where the magnetite phase was mainly removed. In order to compare glass ceramics obtained from original and low iron bottom ashes, microstructural and dilatometric characterizations were performed.

  9. 干、湿式除渣系统对锅炉效率影响的研究%Study on the Impact of Dry and Wet Bottom Ash Handling Systems on Boiler Efficiency

    Institute of Scientific and Technical Information of China (English)

    许华; 张华伦; 王仕能; 党楠

    2013-01-01

    So far the impacts of air-cooling dry-type bottom ash handling system on boiler efficiency are still controversial and very few authoritative conclusions have been drawn.After three years' research on the system,the mathematical models including boiler efficiency and cooling air volume are established.Combining with the tests conducted in two 1 000-MW boilers of one power plant,it is concluded that the dry-type bottom ash handling system does have impacts on boiler combustion and lower the boiler efficiency under most circumstances.In addition,the impacts of the dry-type bottom ash handling system are greater than those of the wet-type system.The easy-cooking coal is not a suitable choice for the boilers with dry-type system.If the coal quality of the power plant fluctuates drastically,it is critical to choose the dry-type system meticulously.%风冷干式除渣系统对锅炉效率的影响目前尚存争议,缺少权威定论.通过为期3年的对干式除渣系统的研究,建立了锅炉效率、炉渣冷却风量等参数的数学模型,坐合对某电厂1000MW锅炉干式除渣系统的运行测试,得出干式除渣系统在多数情况下影响锅炉燃烧、降低锅炉效率;干式除渣系统比湿式除渣系统对锅炉燃烧及效率的影响更大;易结焦煤不宜采用干式除渣系统;当电厂燃煤煤质变化较大时,应慎重采用干式除渣系统等结论.

  10. Environmental assessment of the reuse of municipal solid waste incineration bottom ash in quarry backfilling; Evaluation environnementale de la valorisation de machefers d'incineration d'ordures menageres en remplissage de carriere

    Energy Technology Data Exchange (ETDEWEB)

    Brons-Laot, G.

    2002-10-15

    The leaching behaviour of three different MSWI bottom ashes-based materials containing hydraulic binders is assessed in the conditions specified by the quarry backfilling application. An adapted approach methodology is applied: - physical, mineralogical and chemical characterizations of materials, - use of parametric tests to determine the effect of main scenarios factors on the release, - chemical modelling based on mineralogical and experimental leaching data with geochemical calculation codes, - chemical reaction / transport coupled modelling. The main results demonstrate that: - the batch and dynamic tests allow to obtain enough data to model and to predict the long term behaviour, - the chemical modelling of the solid / liquid equilibrium permits the determination of the chemical reactions involved and the prediction of pollutants solubilization in different chemical contexts, - the new materials (source term) present a low environmental impact in the conditions specified by the considered scenarios. (author)

  11. Environmental assessment of the reuse of municipal solid waste incineration bottom ash in quarry backfilling; Evaluation environnementale de la valorisation de machefers d'incineration d'ordures menageres en remplissage de carriere

    Energy Technology Data Exchange (ETDEWEB)

    Brons-Laot, G.

    2002-10-15

    The leaching behaviour of three different MSWI bottom ashes-based materials containing hydraulic binders is assessed in the conditions specified by the quarry backfilling application. An adapted approach methodology is applied: - physical, mineralogical and chemical characterizations of materials, - use of parametric tests to determine the effect of main scenarios factors on the release, - chemical modelling based on mineralogical and experimental leaching data with geochemical calculation codes, - chemical reaction / transport coupled modelling. The main results demonstrate that: - the batch and dynamic tests allow to obtain enough data to model and to predict the long term behaviour, - the chemical modelling of the solid / liquid equilibrium permits the determination of the chemical reactions involved and the prediction of pollutants solubilization in different chemical contexts, - the new materials (source term) present a low environmental impact in the conditions specified by the considered scenarios. (author)

  12. Geotechnical engineering properties of incinerator ash mixes.

    Science.gov (United States)

    Muhunthan, B; Taha, R; Said, J

    2004-08-01

    The incineration of solid waste produces large quantities of bottom and fly ash. Landfilling has been the primary mode of disposal of these waste materials. Shortage in landfill space and the high cost of treatment have, however, prompted the search for alternative uses of these waste materials. This study presents an experimental program that was conducted to determine the engineering properties of incinerator ash mixes for use as construction materials. Incinerator ash mixes were tested as received and around optimum compacted conditions. Compaction curves, shear strength, and permeability values of fly ash, bottom ash, and their various blends were investigated. Bottom ash tends to achieve maximum dry density at much lower water content than does fly ash. The mixes displayed a change in their cohesion and friction angle values when one of the two mix components was altered or as a result of the addition of water. The permeability of bottom ash is quite comparable to that of sand. The permeability of fly ash lies in the range of those values obtained for silts and clays. A 100% bottom ash compacted at the optimum water content has a lower density value and yields a higher friction angle and cohesion values than most construction fills. This would encourage the use of bottom ash as a fill or embankment material because free drainage of water will prevent the buildup of pore water pressures.

  13. A Cold Model Experimental Study on the Flow Characterisitcs of Bed Baterial in A Fluidized ed Bottom Ash Cooler in a CFB Boiler

    Institute of Scientific and Technical Information of China (English)

    LuXiaofeng; LiYourong

    2000-01-01

    A cold model experimental study on the flowing characteristics of bed meterial between a fluidized bed ash cooler and a furnace of CFB boiler were discussed in this paper.The research results showed that flowing status of the bed material in a bubbling bed,which was run with a circulating fluidized bed together in parallel operation,was influenced by the pressure difference between the CFB and the bubbling bed,the switch status of unlocking air ,and the structure of the exit of the bubbling bed.There was a circulating flow of bed material between CFB and bubbling bed.

  14. Influence of Bed Ash and Fly Ash Replacement in Mortars

    Directory of Open Access Journals (Sweden)

    S. L. Summoogum-Utchanah

    2015-03-01

    Full Text Available The study evaluates the influence of fly ash and bottom ash as partial cement substitutes in mortars by studying the particle size distribution, consistency, flow, fresh density, air content, compressive strength and flexural strength characteristics. The results revealed that fly ash and cement had relatively the same particle size distribution unlike bottom ash. In the fresh state, as the amount of pozzolans increased in the mixtures, the mortars showed an enhancement in workability, were susceptible to water loss by bleeding, and exhibited a decline in fresh density. The early strength gains of the fly ash samples were low but reached higher than the control after 28 days of curing. The flexural strength increased as the fly ash content rose to reach a maximum at 20 % replacement. However, the 2-day compressive strength of bottom ash samples was higher than the control but decreased after 28 days of curing while the flexural strength declined with addition of bottom ash except at 5 % substitution.

  15. Ashes from fluidized bed combustion of residual forest biomass

    NARCIS (Netherlands)

    Cruz, Nuno C.; Rodrigues, Sónia M.; Carvalho, Lina; Duarte, Armando C.; Pereira, Eduarda; Romkens, Paul; Tarelho, Luís A.C.

    2017-01-01

    Although bottom ash (BA) [or mixtures of bottom and fly ash (FA)] from clean biomass fuels is currently used as liming agent, additive for compost, and fertilizer on agricultural and forest soils in certain European countries, in several other countries most of the ashes are currently disposed in la

  16. Settling characteristics of some Indian fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Jain, M.K.; Sastry, B.S. [Indian Institute of Technology, Kharapur (India). Dept. of Mining Engineering

    2003-07-01

    The paper examines the aspects of the solid liquid separation (settling characteristics) of some of the fly ash obtained from coal-fired power plants in India. The application of a coagulating or flocculating agent (polymer) to improve the two properties as indicated is a typical industrial practice. The sources for this study comprise of fly ash, pond ash, and bottom ash and the settling characteristics are studied in conjunction with the flocculating agent polyacrylamide. 4 refs., 4 figs., 3 tabs.

  17. Monitoring of test roads with MSWI bottom ash in the sub-base. Measurements with falling weight deflectometer on test structures in Malmoe and Umeaa; Uppfoeljning av befintliga slaggrusprovvaegar. Fallviktsmaetning paa provstraeckor paa Toerringevaegen i Malmoe och Daavamyran i Umeaa

    Energy Technology Data Exchange (ETDEWEB)

    Arm, Maria [Swedish Geotechnical Inst., Linkoeping (Sweden)

    2005-03-01

    There are a number of Swedish test roads and test areas with processed municipal solid waste incinerator bottom ash, here called MSWI gravel. It is used in different road layers and for different purposes. Many of these have been monitored through falling weight deflectometer (FWD) measurements. The main purpose of this project is to increase the knowledge of the long-term strength of MSWI gravel, when it is used as a road material. Another purpose is to take advantage of the existing test roads. FWD measurements have been performed on two of the existing test roads with MSWI gravel in the sub-base. One road was constructed in 2001 and is situated in Umeaa, close to the Daava power station of Umeaa Energi. The other test road was constructed in 1998 in Toerringe, outside Malmoe. In both cases a test structure as well as a reference structure has been measured. Both test roads have been measured before and the data from this project have been evaluated in the same way as earlier (layer moduli for different layers and surface modulus for the whole road structure respectively). The result is presented and compared with the earlier data. The values obtained for the MSWI gravel have also been related to the corresponding values for the crushed rock material in the reference structures. The result shows that in Toerringe, the stiffness of the MSWI gravel has not changed compared with the results from earlier measurements. However, in Daava the stiffness of the test structure was lower in 2004 than in 2002. In both test roads, the test structure had lower stiffness than the reference structure. In Toerringe, the ratio between the stiffness of the test structure and the stiffness of the reference structure was unchanged. In Daava, however, the stiffness ratio had increased. The stiffness increase that has been observed on an older test road in Linkoeping has not been observed on these roads with MSWI gravel of more 'modern' type. It is maybe due to the longer

  18. Solidification of dewatered sewage sludge using bottom ash of MSWI as skeleton material%以垃圾焚烧底灰为骨料的脱水污泥固化试验

    Institute of Scientific and Technical Information of China (English)

    陈萍; 冯彬; 詹良通

    2014-01-01

    Dehydrate sewage sludge is low in sheared strength, and its landfilling disposal has safety issues. Experimental study on the solidification of dewatered sewage sludge was carried out by using the bottom ash of municipal solid waste incinerator (MSWI) as skeleton material, and using cement, lime, gypsum as solidification materials. Unconfined compressive strength (UCS) tests, water resistance tests, and leaching test were performed to investigate the solidification effect. The experimental results demonstrated that the optimum solidification materials were cement and gypsum, and the optimum adding mixture ratio of dry mass of sewage sludge was 50%. Measured UCS of the solidified sludge met the requirement for safe landfilling. The optimum adding mixture ratio of MSWI bottom ash was 100%, which resulted in the volume change ratio being less than 1.0. The water resistance capacity of the sludge solidified by cement and gypsum was high. The leaching tests showed that gypsum was the optimum solidification material, the measured concentration of Cu, Zn, Pb and COD of the leachate was significantly lower than the untreated sludge. Furthermore, the pH of the leachate was close to 7.0. Leachate was low in toxicity, with minor effect on the environment.%针对机械脱水污泥强度低,难以安全填埋的问题,采用生活垃圾焚烧底灰作为骨架材料和水泥、石灰、石膏作为固化剂,开展污泥固化试验研究,并通过无侧限抗压强度试验、耐水性试验、浸出毒性试验对固化效果进行评价.结果表明,较优的固化剂种类为水泥和石膏,掺入量为污泥干基的50%,无侧限抗压强度可以满足填埋要求.最优垃圾焚烧底灰掺入量为100%,固化污泥增容比小于1.0,能够起到减容作用.水泥、石膏固化污泥耐水性能均较好.浸出毒性试验结果表明,最优固化剂种类为石膏,浸出液Cu、Zn、Pb离子浓度及COD值均较原泥大幅降低,可以起到良好的稳定

  19. Comparison of leachable trace element levels in coal gasifier ash with levels in power plant ash

    Energy Technology Data Exchange (ETDEWEB)

    Bombaugh, K.J.; Milosavljevic, M.; Janes, T.K.

    1984-04-01

    The levels of 14 trace elements in leachates from three types of ash of a common origin coal were compared. The study was conducted over a one year period at the Kosovo plant in Obilic, Yugoslavia comparing coal gasifier ash with fly ash and bottom ash from a coal-fired power plant using lignite from the Dobro Solo mine. Results obtained indicate that levels of Sb, As, Be, Cr, Cu, Pb, Mo, Ni and Zn in gasifier ash leachate were similar to those in fly ash leachate. Barium levels in gasifier ash leachate averaged 2.7 times that in fly ash and selenium levels averaged 0.33 times. The average ratio for the total set was 0.99. The set average, relative to bottom ash, was 2.1 with the nickel ratio differing significantly from the average. Metal oxides, CaO, MgO, Na/SUB/2O, K/SUB/2O and MgO; in the Kosovo gasifier ash were found at levels similar to those in Kosovo fly ash, and except for K/SUB/2O, were approximately twice those in bottom ash. Concentration levels of all components showed relatively small variations averaging 50% of their mean annual concentration over the test period. (14 refs.)

  20. 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.

  1. 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.)

  2. 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.)

  3. Leachability of municipal solid waste ashes in simulated landfill conditions.

    Science.gov (United States)

    Li, Loretta Y; Ohtsubo, Masami; Higashi, Takahiro; Yamaoka, Shinya; Morishita, Tomotaka

    2007-01-01

    In Japan the volume of municipal solid waste is reduced by incineration, with fly ash and bottom ash disposed in controlled landfills. The leachability of anions and heavy metal cations, Zn, Cu and Pb, from MSW fly ash and bottom ash at different pHs was examined using batch- and column-leaching tests. The MSW ashes had a high capacity for neutralizing acids. Behaviour during leaching depended on the pH of the solution. For the volumes applied, the leachabilities of MSW fly ash were very similar at pHs from 3 to 6. Due to its amphoteric nature, Pb is leachable at pHs of approximately 10 or more, with leachate concentrations of about 3 and 3-10mg/L for the fly ash and bottom ash, respectively, much higher than for Zn and Cu. Pb concentrations for most leaching solutions were 1 and 3mg/L for the fly ash and bottom ash, respectively. Zn, and Cu leached at low concentrations for solutions of pH 3-6. Na and K ions leached at high concentrations of approximately 5000 mg/L in the first batch leaching test, decreasing to 10mg/L by the fourth leach. Ca and Mg ions leached more gradually than Na and K. Cl(-) and SO(4)(2+) ions were the major anions in the MSW ash. The high pH and cation leaching are expected to have negative impacts on the performance of clay liners.

  4. Element budgets of forest biomass combustion and ash fertilisation - a Danish case-study

    DEFF Research Database (Denmark)

    Ingerslev, Morten; Skov, Simon; Sevel, Lisbeth

    2011-01-01

    the retention of various elements in the different ash fractions and utilise the nutrient recovery to evaluate the fertiliser quality of the examined ash. The mass and element flux of wood chips, bottom ash, cyclone fly ash and condensation sludge at Ebeltoft central heating plant was studied over a four day...

  5. Stabilization/solidification of TSCA incinerator ash

    Energy Technology Data Exchange (ETDEWEB)

    Spence, R.D.; Trotter, D.R.; Francis, C.L.; Morgan, I.L.

    1994-06-01

    Stabilization/solidification is a well-known waste treatment technique that utilizes different additives and processes. The Phoenix Ash Technology of the Technical Innovation Development Engineering Company is such a technique that uses Cass C fly ash and mechanical pressure to make brick waste forms out of solid wastes, such as the bottom ash from the Toxic Substances Control Act incinerator at the Oak Ridge K-25 Site. One advantage of this technique is that no volume increase over the bulk volume of the bottom ash occurs. This technique should have the same high pH stabilization for Resource Conservation and Recovery Act metals as similar techniques. Also, consolidation of the bottom ash minimizes the potential problems of material dispersion and container corrosion. The bottom ash was spiked with {sup 99}{Tc} to test the effectiveness of the bricks as a physical barrier. The {sup 99}{Tc} leachability index measured for these bricks was 6.8, typical for the pertechnetate anion in cementitious waste forms, indicating that these bricks have accessible porosity as high as that of other cementitious waste forms, despite the mechanical compression, higher waste form density, and water resistant polymer coating.

  6. 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)

  7. Health Risk Assessment of Heavy Metal Pollution of Agricultural Use of Municipal Solid Waste Incineration Bottom Ashes%村镇生活垃圾焚烧底渣农用的重金属污染风险评价

    Institute of Scientific and Technical Information of China (English)

    张刚; 王德建; 俞元春; 王灿; 庄锦贵

    2016-01-01

    随着生活垃圾焚烧处理方式的不断推广,生活垃圾焚烧底渣的处置也成为一个日益严峻的问题。为了明确生活垃圾底渣农用的可行性,于2014年在江苏常熟农业生态实验站进行了小白菜(Brassica rapa L. Chinensis Group.)盆栽试验,各施肥处理土壤中分别添加底渣的比例为0%、5%、10%、20%、50%、100%,以不施肥处理和单施底渣(10%)处理为对照。于小白菜收获时,取样分析小白菜产量、品质,以及小白菜和土壤中Cd、Cr、Cu、Ni、Pb、Zn含量,并采用内梅罗综合污染指数法和目标危害系数法评价了底渣农用的重金属污染风险。结果表明,施用适量的底渣可以有效增加小白菜产量,亦增加了小白菜中可溶性糖、维生素 C 和硝酸盐含量,并且硝酸盐含量未超过中国无公害蔬菜安全要求;小白菜地上部重金属含量和土壤重金属含量在不同处理中均随底渣施用比例的增加而增加,且底渣施用量超过12.2%时,土壤内梅罗综合污染指数大于1,土壤呈轻度重金属污染,底渣施用量超过15%时,小白菜地上部重金属Cr含量超过中国食物污染物的限量标准;小白菜单一重金属目标风险系数在不同处理中均小于1,而底渣用量大于或等于10.7%时小白菜重金属复合目标风险系数大于1,存在食用健康风险,健康风险以Pb、Cd为主,并且儿童更易遭受小白菜重金属危害。因此,在保证小白菜产量、品质和土壤安全下,底渣一次性安全施用比例不能超过10%。%As incineration is more widely chosen as one of the major treatments of municipal solid waste in China, the disposal of municipal solid waste incineration bottom ashes (MSWIBA) has become an increasingly serious problem. In order to identify the feasibility of agricultural use of MSWIBA a pot experiment in greenhouse was tested with a local pakchoi as material in Changshu agro

  8. Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling

    Science.gov (United States)

    Park, D.; Woo, N. C.; Kim, H.; Yoon, H.; Chung, D.

    2011-12-01

    By 2009, coal ashes produced from coal-based power plants in Korea have been reused as cement supplement materials; however, the rest is mostly disposed in landfills inside the plant properties. Continuous production of coal ashes and limited landfill sites require more recycles of coal ashes as base materials, specifically in constructions of roads and of huge industrial complex. Previous researches showed that coal ashes could contain various metals such as arsenic(As), chromium(Cr), lead(Pb), nickel(Ni), selenium(Se), etc. In this study, we collected four types of bottom ashes and two of fly ashes from four coal-based power plants. These ash samples were tested with distilled water through the column leaching process in oxidized conditions. The column test results were compared with those of total digestion, sequential extraction processes and TCLP. Concentrations of metals in outflows from columns are generally greater in fly ashes than in bottom ashes, specifically for As, Se, B, Sr and SO4. Only one fly ash (J2-F) shows high concentrations of arsenic and selenium in leachate. Sequential extraction results indicate that these metals are in readily soluble forms, such as adsorbed, carbonated, and reducible forms. Results of TCLP analysis indicate no potential contaminants leached from the ashes. In conclusion, recycling of coal combustion ashes could be encouraged with proper tests such as sequential and leaching experiments.

  9. Associative properties of {sup 137}Cs in biofuel ashes

    Energy Technology Data Exchange (ETDEWEB)

    Ravila, A.; Holm, E. [Lund Univ. (Sweden). Dept. of Radiation Physics

    1999-07-01

    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.

  10. Bottom Production

    CERN Document Server

    Nason, P; Schneider, O; Tartarelli, F; Vikas, P; Baines, J T M; Baranov, S P; Bartalini, P; Bay, A; Bouhova-Thacker, E; Cacciari, M; Caner, A; Coadou, Y; Corti, G; Damet, J; Dell'Orso, R; De Mello-Neto, J R T; Domenech, J L; Drollinger, V; Eerola, Paule Anna Mari; Ellis, Nick; Epp, B; Frixione, Stefano; Gadomski, S; Gavrilenko, I; Gennai, Simone; George, S; Ghete, V M; Guy, L P; Hasegawa, Y; Iengo, R; Jacholkowska, A; Jones, R; Kharchilava, A I; Kneringer, E; Koppenburg, P; Korsmo, M; Krämer, M; Labanca, N; Lehto, M H; Maltoni, F; Mangano, Michelangelo L; Mele, S; Nairz, A; Nakada, Tatsuya; Nikitin, N V; Nisati, A; Norrbin, E; Palla, Fabrizio; Rizatdinova, F K; Robins, S A; Rousseau, D; Sanchis-Lozano, M A; Shapiro, M; Sherwood, P; Smirnova, L; Smizanska, M; Starodumov, Andrei; Stepanov, N; Voft, R

    2000-01-01

    We review the prospects for bottom production physics at the LHC. Members of the working group who has contributed to this document are: J. Baines, S.P. Baranov, P. Bartalini, A. Bay, E. Bouhova, M. Cacciari, A. Caner, Y. Coadou, G. Corti, J. Damet, R. Dell'Orso, J.R.T. De Mello Neto, J.L. Domenech, V. Drollinger, P. Eerola, N. Ellis, B. Epp, S. Frixione, S. Gadomski, I. Gavrilenko, S. Gennai, S. George, V.M. Ghete, L. Guy, Y. Hasegawa, P. Iengo, A. Jacholkowska, R. Jones, A. Kharchilava, E. Kneringer, P. Koppenburg, H. Korsmo, M. Kraemer, N. Labanca, M. Lehto, F. Maltoni, M.L. Mangano, S. Mele, A.M. Nairz, T. Nakada, N. Nikitin, A. Nisati, E. Norrbin, F. Palla, F. Rizatdinova, S. Robins, D. Rousseau, M.A. Sanchis-Lozano, M. Shapiro, P. Sherwood, L. Smirnova, M. Smizanska, A. Starodumov, N. Stepanov, R. Vogt

  11. Bottom production

    Energy Technology Data Exchange (ETDEWEB)

    Baines, J.; Baranov, S.P.; Bartalini, P.; Bay, A.; Bouhova, E.; Cacciari, M.; Caner, A.; Coadou, Y.; Corti, G.; Damet, J.; Dell-Orso, R.; De Mello Neto, J.R.T.; Domenech, J.L.; Drollinger, V.; Eerola, P.; Ellis, N.; Epp, B.; Frixione, S.; Gadomski, S.; Gavrilenko, I.; Gennai, S.; George, S.; Ghete, V.M.; Guy, L.; Hasegawa, Y.; Iengo, P.; Jacholkowska, A.; Jones, R.; Kharchilava, A.; Kneringer, E.; Koppenburg, P.; Korsmo, H.; Kramer, M.; Labanca, N.; Lehto, M.; Maltoni, F.; Mangano, M.L.; Mele, S.; Nairz, A.M.; Nakada, T.; Nikitin, N.; Nisati, A.; Norrbin, E.; Palla, F.; Rizatdinova, F.; Robins, S.; Rousseau, D.; Sanchis-Lozano, M.A.; Shapiro, M.; Sherwood, P.; Smirnova, L.; Smizanska, M.; Starodumov, A.; Stepanov, N.; Vogt, R.

    2000-03-15

    In the context of the LHC experiments, the physics of bottom flavoured hadrons enters in different contexts. It can be used for QCD tests, it affects the possibilities of B decays studies, and it is an important source of background for several processes of interest. The physics of b production at hadron colliders has a rather long story, dating back to its first observation in the UA1 experiment. Subsequently, b production has been studied at the Tevatron. Besides the transverse momentum spectrum of a single b, it has also become possible, in recent time, to study correlations in the production characteristics of the b and the b. At the LHC new opportunities will be offered by the high statistics and the high energy reach. One expects to be able to study the transverse momentum spectrum at higher transverse momenta, and also to exploit the large statistics to perform more accurate studies of correlations.

  12. Ash behavior and de-fluidization in low temperature circulating fluidized bed biomass gasifier

    DEFF Research Database (Denmark)

    Narayan, Vikas

    . It was observed that of the total fuel ash entering the system, a large fraction (40-50%) of the ash was retained in the secondary cyclone bottoms and a lower amount (8-10%) was released as dust in the exit gas; the residual ash was accumulated within the fluidized bed system. A dominant fraction of alkali...... by the ash particle size and the cut size of the primary and secondary cyclones. A model accounting for the ash collection by the plant cyclones was developed which predicted the product gas ash particle release reasonably well. The present work also aims to understand the effect of biomass fuel ash...

  13. Ash and heavy metals in fluidized bed-combustion; Tuhka ja raskasmetallit puuperaeisen jaetteen kerrosleijupoltossa

    Energy Technology Data Exchange (ETDEWEB)

    Kaessi, T.; Aittoniemi, P. [IVO International, Vantaa (Finland)

    1996-12-01

    Combustion ashes and submicron fly ash particles were characterized in two industrial boilers (bubbling vs. circulating fluidized bed) burning paper mill deinking sludge and bark or wood as support fuel. Bulk samples from fly ash, circulating ash and bottom ash were analyzed. Fine particles in fly ash were monitored and sampled for microscopic studies. The mass size distribution of fly ash was measured and the chemical composition according to particle size was analyzed. The results showed that ash consists of large and friable clusters formed by sintering of small mineral particles originating from paper fillers. Very few ash particles were fused and they were found only among the smallest particles. No agglomerates of fused particles were found. If the residence time in furnace is long enough sintering may proceed further and ash structure grows more dense. No indication of ash vaporization was detected. These results were similar for bubbling and circulating fluidized bed boilers. (author)

  14. Rapid toxicity screening of gasification ashes.

    Science.gov (United States)

    Zhen, Xu; Rong, Le; Ng, Wei Cheng; Ong, Cynthia; Baeg, Gyeong Hun; Zhang, Wenlin; Lee, Si Ni; Li, Sam Fong Yau; Dai, Yanjun; Tong, Yen Wah; Neoh, Koon Gee; Wang, Chi-Hwa

    2016-04-01

    The solid residues including bottom ashes and fly ashes produced by waste gasification technology could be reused as secondary raw materials. However, the applications and utilizations of these ashes are very often restricted by their toxicity. Therefore, toxicity screening of ash is the primary condition for reusing the ash. In this manuscript, we establish a standard for rapid screening of gasification ashes on the basis of in vitro and in vivo testing, and henceforth guide the proper disposal of the ashes. We used three different test models comprising human cell lines (liver and lung cells), Drosophila melanogaster and Daphnia magna to examine the toxicity of six different types of ashes. For each ash, different leachate concentrations were used to examine the toxicity, with C0 being the original extracted leachate concentration, while C/C0 being subsequent diluted concentrations. The IC50 for each leachate was also quantified for use as an index to classify toxicity levels. The results demonstrated that the toxicity evaluation of different types of ashes using different models is consistent with each other. As the different models show consistent qualitative results, we chose one or two of the models (liver cells or lung cells models) as the standard for rapid toxicity screening of gasification ashes. We may classify the gasification ashes into three categories according to the IC50, 24h value on liver cells or lung cells models, namely "toxic level I" (IC50, 24h>C/C0=0.5), "toxic level II" (C/C0=0.05gasification plants every day. Subsequently, appropriate disposal methods can be recommended for each toxicity category. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Screening coal combustion fly ashes for application in geopolymers

    NARCIS (Netherlands)

    Valcke, S.L.A.; Pipilikaki, P.; Sarabér, A.J.; Fischer, H.R.; Nugteren, H.W.

    2013-01-01

    Driven by cost and sustainability, secondary resource materials such as fly ash, blast furnace slag, and bottom ash are increasingly used for alternative types of concrete binders, such as geopolymers. Because secondary resources may be highly variable from the perspective of geopolymers, it is ofte

  16. Utilization of blended fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash in geopolymer.

    Science.gov (United States)

    Chindaprasirt, Prinya; Rattanasak, Ubolluk

    2010-04-01

    In this paper, synthesis of geopolymer from fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash was studied in order to effectively utilize both ashes. FBC-fly ash and bottom ash were inter-ground to three different finenesses. The ashes were mixed with as-received PCC-fly ash in various proportions and used as source material for synthesis of geopolymer. Sodium silicate (Na(2)SiO(3)) and 10M sodium hydroxide (NaOH) solutions at mass ratio of Na(2)SiO(3)/NaOH of 1.5 and curing temperature of 65 degrees C for 48h were used for making geopolymer. X-ray diffraction (XRD), scanning electron microscopy (SEM), degree of reaction, and thermal gravimetric analysis (TGA) were performed on the geopolymer pastes. Compressive strength was also tested on geopolymer mortars. The results show that high strength geopolymer mortars of 35.0-44.0MPa can be produced using mixture of ground FBC ash and as-received PCC-fly ash. Fine FBC ash is more reactive and results in higher degree of reaction and higher strength geopolymer as compared to the use of coarser FBC ash. Grinding increases reactivity of ash by means of increasing surface area and the amount of reactive phase of the ash. In addition, the packing effect due to fine particles also contributed to increase in strength of geopolymers.

  17. Bench-scale synthesis of zeolite A from subbituminous coal ashes with high crystalline silica content

    Energy Technology Data Exchange (ETDEWEB)

    Chareonpanich, M.; Jullaphan, O.; Tang, C. [Kasetsart University, Bangkok (Thailand). Dept. of Chemical Engineering

    2011-01-15

    In this present work, fly ash and bottom ash with high crystalline silica content were obtained from the coal-fired boilers within the paper industries in Thailand. These coal ashes were used as the basic raw materials for synthetic zeolite production. The crystal type and crystallinity, specific surface area and pore size, and textural properties of zeolite products were characterized by using X-ray diffraction spectroscopy (XRD), N{sub 2} sorption analysis, and Scanning Electron Microscopy (SEM), respectively. It was found that sodalite octahydrate was selectively formed via the direct conventional (one-step) synthesis, whereas through a two-step, sodium silicate preparation and consecutive zeolite A synthesis process, 94 and 72 wt.% zeolite A products could be produced from the fly ash and bottom ash, respectively. The cation-exchange capacity (CEC) of fly ash and bottom ash-derived zeolite A products were closely similar to that of the commercial grade zeolite A.

  18. Environmental impact of manganese due to its leaching from coal fly ash.

    Science.gov (United States)

    Prasad, Bably; Mondal, Kajal K R

    2009-01-01

    In India, so far not much efforts have been made to use coal ash as backfill material in underground/ open cast mines and to predict its subsequent effect on ground water quality. One of the main problems in disposing of big quantities of coal ash is the possible leaching of different pollutants, including manganese. A thorough investigation regarding leaching of manganese from different fly ashes is required to know the impact of manganese due to its leaching from fly ash to ground water as well as surface water. In the present study, short term and long term leaching studies have been carried out on fly ash, bottom ash, pond ash and weathered ash of Chandrapura thermal power plant, Bokaro, Jharkhand and Ramagundam thermal power plant, Ramagundam, Andhra Pradesh. The amount of manganese released in different experiments has been evaluated. The leachate of Chandrapura fly ash has more manganese concentration (0.2001 mg/L) than the leachate of bottom ash, pond ash and weathered ash. A field investigation at Damoda abandoned open cast mine, filled with pond ash of Chandrapura thermal power plant revealed that concentration of manganese in ground water beneath the ash filled mine has been found very high (maximum up to 6.0 mg/L). But its migration to a long distance has not been seen. Remedial measures for coal ash disposal have also been formulated.

  19. Chemical fractionation method for characterization of biomass-based bottom and fly ash fractions from large-sized power plant of an integrated pulp and paper mill complex%化学分离法分析大型纸浆发电厂废渣中生物质底灰和飞灰成分

    Institute of Scientific and Technical Information of China (English)

    Risto PÖYKIÖ; Hannu NURMESNIEMI; Olli DAHL; Mikko MÄKELÄ

    2014-01-01

    The aim of this study was to extract the biomass-based bottom and fly ash fractions by a three-stage fractionation method for water-soluble (H2O), ammonium-acetate (CH3COONH4) and hydrochloric acid (HCl) fractions in order to access the leaching behaviour of these residues. Except for Mo, S, Na and elements whose concentrations were lower than the detection limits, the extractable element concentrations in both ash fractions followed the order H2O

  20. Chemical characterization of ash from gasification of alfalfa stems: Implications for ash management

    Energy Technology Data Exchange (ETDEWEB)

    Mozaffari, M.; Rosen, C.J.; Russelle, M.P.; Nater, E.A.

    2000-06-01

    Electricity generation from biomass is an attractive option from an environmental perspective. Pilot studies have indicated that alfalfa (Medicago sativa L.) stems are suitable feedstock for energy generation via gasification. Detailed information on chemical characteristics of the ash generated from gasification of alfalfa stem is required to develop environmentally and economically sound ash management strategies. Alfalfa fly and bottom ashes were characterized with respect to chemical properties that are important in developing ash management practices with emphasis on beneficial utilization as a soil amendment. Mean concentrations of total C, K, Ca, and Cl were 424, 120, 85, and 26 g kg{sup {minus}1}, respectively, in fly ash. In bottom ash, the mean concentrations of C, K, and Ca, were 63, 61, and 193 g kg{sup {minus}1}. Concentrations of total Pb, As, Cd, Co, and Se were below detection limits in both ash types. Naphthalene ranged from 6.2 to 74 mg kg{sup {minus}1}, but concentrations of many other polyaromatic hydrocarbons were low or below mg kg{sup {minus}1} detection limits. Available K and P in fly ash were 90 to 120 and 8 to 10 g kg{sup {minus}1}, respectively. Mean CaCO{sub 3} equivalent value of fly ash was 400 g kg{sup {minus}1}, its electrical conductivity (EC) and pH were 127 dS m{sup {minus}1} and 11.5, respectively. These results suggest that when managed properly, gasified alfalfa ash could potentially be utilized as a beneficial soil amendment with few potential environmental concerns.

  1. Agglomeration in Stripper Ash Coolers and Its Possible Remedial Solutions: a Case Study

    Science.gov (United States)

    Singh, Ravi Inder

    2016-04-01

    The bottom ash of circulating fluidized bed (CFB) boiler contains large amounts of physical heat. When low quality coals are used in these types of boilers, the ash content is normally more than 40 % and the physical heat loss is approximately 3 % if the bottom ash is discharged without cooling. Bottom ash cooler (BAC) is often used to treat the high temperature bottom ash to reclaim heat, and to facilitate the easily handling and transportation of ash. The CFB boiler at BLA Power, Newari, MP (India) is facing problems of clinker formation in strip ash coolers of plant since the installation of unit. These clinkers are basically agglomerates, which leads to defluidization of stripper ash cooler (BAC) units. There are two strip ash coolers in unit. Each strip ash cooler is capable of working independently. The proper functioning of both strip coolers is very important as it is going to increase the combustion efficiency of boiler by stripping of fine unburnt coal particles from ash, which are injected into the furnace. In this paper causes, characterization of agglomerates, thermo gravimetric analysis of fuel used, particular size distribution of coal and sand and possible remedial solution to overcome these agglomerates in strip ash coolers has also been presented. High temperature in compact separators, non uniform supply of coal and not removing small agglomerates from stripper ash cooler are among main causes of agglomeration in stripper ash cooler. Control of compact separator temperature, replacing 10-12 % of bed material and cleaning stripper ash cooler periodically will decrease agglomeration in stripper ash cooler of unit.

  2. Financialization and financial profit

    Directory of Open Access Journals (Sweden)

    Arturo Guillén

    2014-09-01

    Full Text Available This article starts from the critical review of the concept of financial capital. I consider it is necessary not to confuse this category with of financialization, which has acquired a certificate of naturalization from the rise of neoliberalism. Although financial monopoly-financial capital is the hegemonic segment of the bourgeoisie in the major capitalist countries, their dominance does not imply, a fortiori, financialization of economic activity, since it depends of the conditions of the process reproduction of capital. The emergence of joint stock companies modified the formation of the average rate of profit. The "promoter profit" becomes one of the main forms of income of monopoly-financial capital. It is postulated that financial profit is a kind of "extraordinary surplus-value" which is appropriated by monopoly-financial capital by means of the monopolistic control it exerts on the issue and circulation of fictitious capital.

  3. Flue gas desulfurization gypsum and fly ash

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. [Ash Meadows Purchase Proposal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A proposal sent to the Richard King Mellon Foundation for a loan to fund the purchase of Ash Meadows by the Nature Conservancy. Ash Meadows, set outside of Las Vegas...

  5. Heavy metal characterization of circulating fluidized bed derived biomass ash.

    Science.gov (United States)

    Li, Lianming; Yu, Chunjiang; Bai, Jisong; Wang, Qinhui; Luo, Zhongyang

    2012-09-30

    Although the direct combustion of biomass for energy that applies circulating fluidized bed (CFB) technology is steadily expanding worldwide, only few studies have conducted an environmental assessment of biomass ash thus far. Therefore, this study aims to integrate information on the environmental effects of biomass ash. We investigated the concentration of heavy metal in biomass ash samples (bottom ash, cyclone ash, and filter ash) derived from a CFB boiler that combusted agricultural and forest residues at a biomass power plant (2×12 MW) in China. Ash samples were gathered for the digestion and leaching test. The heavy metal content in the solution and the leachate was studied via an inductively coupled plasma-mass spectrometer and a Malvern Mastersizer 2000 mercury analyzer. Measurements for the chemical composition, particle size distribution, and the surface morphology were carried out. Most of the metals in cyclone ash particles were enriched, whereas Ti and Hg were enriched in filter ash. Residence time contributed most to heavy metal enrichment. Under HJ/T 300 conditions, the heavy metals showed serious leaching characteristics. Under EN 12457-2 conditions, leaching behavior was hardly detected.

  6. Granulation of coal fly ash by using different types of granule agents

    Science.gov (United States)

    Agusta, H.; Nisya, F. N.; Iman, R. N.; Bilad, D. B. C.

    2017-05-01

    The use of coal produces about 5% solid pollutant in the form of ash (fly ash and bottom ash). Of the total ash produced, about 10-20% is bottom ash and 80-90% is fly ash. This study was aimed at obtaining a type of adhesive which could be used as a fly granulation material for soil conditioner. The study was conducted at the pilot plant of Surfactant and Bioenergy Research Center (SBRC) LPPM IPB from April to August 2016. The fly ash used in this study was obtained from Kalimantan. A pan granulator was used in fly ash granule making process. Granule agent materials were diluted in the concentration of 5, 10, and 15%. Different types of granule agents, namely SBRC-M, SBRC-T, and SBRC-SC were used. The formed fly ash granules were then analyzed for their physical properties including particle density, fly ash granule pH, fly ash granule durability, and fly ash granule water holding capacity. Results showed that fly ash granules made from 15% of SBRC-M had the highest particle density (0.75 g/cm3). Fly ash granules made with SBRC-M had higher pH (10) than those made by using SBRC-SC adhesive (9.3) and SBRC-T (9). SBRC-T was found as the granule agent material which produced fly ash granules with the highest durability levels on average. In this study, the use of SBRC-M granule agent resulted in higher water holding capacity (WHC) (40.62%) than did SBRC-SC (38.79%) and SBRC-T (36.85%). As a granule agent, compared to SBRC-SC and SBRC-T, SBRC-M could produce fly ash granules with highest particle density, highest pH, good durability, and best water holding capacity.

  7. 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

  8. Financial history and financial economics

    OpenAIRE

    Turner, John D.

    2014-01-01

    This essay looks at the bidirectional relationship between financial history and financial economics. It begins by giving a brief history of financial economics by outlining the main topics of interest to financial economists. It then documents and explains the increasing influence of financial economics upon financial history, and warns of the dangers of applying financial economics unthinkingly to the study of financial history. The essay proceeds to highlight the many insights that financi...

  9. Financial history and financial economics

    OpenAIRE

    Turner, John D.

    2014-01-01

    This essay looks at the bidirectional relationship between financial history and financial economics. It begins by giving a brief history of financial economics by outlining the main topics of interest to financial economists. It then documents and explains the increasing influence of financial economics upon financial history, and warns of the dangers of applying financial economics unthinkingly to the study of financial history. The essay proceeds to highlight the many insights that financi...

  10. Financial modeling: Rx for financial success.

    Science.gov (United States)

    Marino, D

    2001-01-01

    In an era of managed care, cost cutting and finding ways to increase revenue are key goals in the survival of group practices. Many practices find that they have to boost their revenue by a certain amount (for example, 20-30% within the next three years) to maintain viability in the health care marketplace. Understanding how to generate that revenue and influence short-term and long-term financial outcomes is a far trickier process. This article details how practice administrators can influence a practice's bottom line through a three-step process: (1) identify the components of the practice's financial performance and drivers of performance results, (2) diagnose the practice's current financial situation, and (3) pinpoint benchmarks and targets for success.

  11. 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.

  12. Thermal co-treatment of combustible hazardous waste and waste incineration fly ash in a rotary kiln.

    Science.gov (United States)

    Huber, Florian; Blasenbauer, Dominik; Mallow, Ole; Lederer, Jakob; Winter, Franz; Fellner, Johann

    2016-12-01

    As current disposal practices for municipal solid waste incineration (MSWI) fly ash are either associated with significant costs or negative environmental impacts, an alternative treatment was investigated in a field scale experiment. Thereto, two rotary kilns were fed with hazardous waste, and moistened MSWI fly ash (water content of 23%) was added to the fuel of one kiln with a ratio of 169kg/Mg hazardous waste for 54h and 300kg/Mg hazardous waste for 48h while the other kiln was used as a reference. It was shown that the vast majority (>90%) of the inserted MSWI fly ash was transferred to the bottom ash of the rotary kiln. This bottom ash complied with the legal limits for non-hazardous waste landfills, thereby demonstrating the potential of the investigated method to transfer hazardous waste (MSWI fly ash) into non-hazardous waste (bottom ash). The results of a simple mixing test (MSWI fly ash and rotary kiln bottom ash have been mixed accordingly without thermal treatment) revealed that the observed transformation of hazardous MSWI fly ash into non-hazardous bottom ash during thermal co-treatment cannot be referred to dilution, as the mixture did not comply with legal limits for non-hazardous waste landfills. For the newly generated fly ash of the kiln, an increase in the concentration of Cd, K and Pb by 54%, 57% and 22%, respectively, was observed. In general, the operation of the rotary kiln was not impaired by the MSWI fly ash addition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. 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

  14. 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...

  15. Peak exposures to main components of ash and gaseous diesel exhausts in closed and open ash loading stations at biomass-fuelled power plants.

    Science.gov (United States)

    Laitinen, Juha; Koponen, Hanna; Sippula, Olli; Korpijärvi, Kirsi; Jumpponen, Mika; Laitinen, Sirpa; Aatamila, Marjaleena; Tissari, Jarkko; Karhunen, Tommi; Ojanen, Kari; Jokiniemi, Jorma; Korpinen, Leena

    2017-10-01

    Fly and bottom ashes are collected at power plants to reduce the environmental effects of energy production. However, handling the ashes causes health problems for operators, maintenance workers and truck drivers at the power plants. Hence, we evaluated ash loaders' peak inhalation exposures to the chemical components of ash and diesel exhausts in open and closed ash loading stations at biomass-fuelled combined heat and power plants. We also carried out chemical and morphological analyses of the ashes to evaluate their health hazard potential in order to find practical technical measures to reduce workers' exposure. On the basis of X-ray diffraction analyses, the main respirable crystalline ash compounds were SiO2, CaSO4, CaO, Ca2Al2SiO7, NaCl and Ca3Al2O6 in the fly ashes and SiO2, KAlSi3O8, NaAlSi3O8 and Ca2Al2SiO7 in the bottom ashes. The short-term exposure levels of respirable crystalline silica, inhalable inorganic dust, Cr, Mn, Ni and nitric oxide exceeded their Finnish eight hours occupational exposure limit values in the closed ash loading station. According to our observations, more attention should be paid to the ash-moistening process, the use of tank trucks instead of open cassette flatbed trucks, and the sealing of the loading line from the silo to the truck which would prevent spreading the ash into the air. The idling time of diesel trucks should also be limited, and ash loading stations should be equipped with exhaust gas ventilators. If working conditions make it impossible to keep to the OEL values, workers must use respirators and protect their eyes and skin. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Study of the Bolton ash from municipal solid waste combustion; Estudio a escala piloto de la maduracion de las escorias de incineracion de RSU

    Energy Technology Data Exchange (ETDEWEB)

    Chimenos, J. M.; Fernandez, A. I.; Segarra, M.; Espiell, F. [Universidad de Barcelona (Spain); Nadal, R.

    2000-07-01

    The natural weathering of the bottom ash from MSWI for an estimated period of two to three months before their final disposal, or their eventual utilization is the method more used in the treatment of bottom ash, due to its low investment and operating cost. Carbonation and oxidation are some of the reactions that may occur in the aging of bottom ash, which provide a chemical stability, decreasing the solubility of many elements and consequently decreasing its release,. The aim of this paper is to determine the natural weathering effects on the behaviour leaching of MSWI bottom ash a function of time and experimental conditions. The relationship between pH values obtained in the natural weathering of MSWI bottom ash and the leaching behaviour of the most important heavy metals has been established. (Author) 17 refs.

  17. Balancing Priorities and Measuring Success: A Triple Bottom Line Framework for International School Leaders

    Science.gov (United States)

    MacDonald, James

    2009-01-01

    Drawing upon a multiple bottom line concept, which was originally developed for the business world, this article proposes a triple bottom line framework for analyzing and assessing the performance of international schools. The author contends that international schools can be broken down into three bottom lines: one "financial," one "academic" and…

  18. Financial Stability and Financial Inclusion

    OpenAIRE

    Morgan, Peter J; Pontines, Victor

    2014-01-01

    Developing economies are seeking to promote financial inclusion, i.e., greater access to financial services for low-income households and firms, as part of their overall strategies for economic and financial development. This raises the question of whether financial stability and financial inclusion are, broadly speaking, substitutes or complements. In other words, does the move toward greater financial inclusion tend to increase or decrease financial stability? A number of studies have sugge...

  19. Utilization of ash from municipal solid waste combustion. Final report, Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.M.; Hartman, R.M.; Kort, D.; Rapues, N.

    1994-09-01

    This ash study investigates several aspects of Municipal Waste Combustion (MWC) ash utilization to develop an alternative to the present disposal practice of landfilling in a lined monofill. Ash was investigated as a daily or final cover for municipal waste in the landfill to prevent erosion and as a road construction aggregate. Samples of eight mixtures of ash and other materials, and one sample of soil were analyzed for chemical constituents. Biological tests on these mixters were conducted, along with erosion tests and sieve analyses. A chemical analysis of each sieve size was conducted. Geotechnical properties of the most promising materials were made. Findings to this point include: all ash samples take have passed the EPA TCLP testing; chemical analysis of bottom and combined ash samples indicate less than expected variability; selected ash mixtures exhibited very low coefficients of hydraulic conductivity; all but one of the ash mixtures exhibited greater erosion resistance than the currently used landfill cover material; MWC combined analysis indicates this is a viable alternative for landfill cover; MWC ash size reactions and chemical analysis show bottom and combined ash to be a viable alternative for road construction.

  20. Co-combustion of coal and sewage sludge: chemical and ecotoxicological properties of ashes.

    Science.gov (United States)

    Barbosa, Rui; Lapa, Nuno; Boavida, Dulce; Lopes, Helena; Gulyurtlu, Ibrahim; Mendes, Benilde

    2009-10-30

    The co-combustion of sewage sludge (SS) and coal is widely used for the treatment and thermal valorization of SS produced in wastewater treatment plants. The chemical and ecotoxicological properties of the ashes produced in this thermal treatment have not been fully studied. Two combustion tests were performed in a fluidized bed combustor. Colombian coal was used as fuel in test A. A blend (1+1) of this coal and a stabilized SS (Biogran) was used in a second test B. Samples of the bottom and fly ashes trapped in two sequential cyclones were collected. The characterization of the ashes was focused on two main aspects: (1) the bulk content of a set of metals and (2) the characterization of eluates produced according to the European Standard leaching test EN 12457-2. The eluates were submitted to an ecotoxicological characterization for two bio-indicators. In what concerns the bulk content of ashes, both combustion tests have produced ashes with different compositions. The ashes formed during the co-combustion test have shown higher concentrations of metals, namely Cr, Cu, Ni, Pb, Zn and Fe for all ashes. The leaching test has shown low mobility of these elements from the by-products produced during the combustion and co-combustion tests. Cr and Cr(VI) were mainly detected in the eluates of the 1st cyclone ashes produced in both combustion tests and in the 2nd cyclone ashes produced in the co-combustion test. Considering the ecotoxicity assays, the eluates of bottom and fly ashes for both combustion and co-combustion tests have shown low ecotoxic levels. The micro-crustacean Daphnia magna was generally more sensitive than the bacterium Vibrio fischeri. CEMWE criterion has allowed to classify the bottom ashes for both combustion and co-combustion tests as non-toxic residues and the fly ashes collected in both cyclones as toxic.

  1. Re-burning of ash in grate boilers; Omfoerbraenning av askor i rosterpannor

    Energy Technology Data Exchange (ETDEWEB)

    Bergqvist, Kristina; Myringer, Aase; Nordgren, Daniel; Rydberg, Stina [Vattenfall Utveckling AB, Aelvkarleby (Sweden)

    2005-03-01

    High contents of unburnt carbon in ashes that are dumped or recycled, is questionable from both an economical and an environmental point of view. The content of unburnt carbon in bottom and fly ash from grate boilers varies greatly between different plants but can sometimes exceed 50 %. Re-burning of ash that is separated before a final dust separation, is a relatively cheep and simple method for reducing the content of unburnt carbon in ash, which both reduces the fuel cost and the deposit cost, i.e. the cost of landfilling or recycling. As from 2005 it is prohibited to deposit ash with a too high content of unburnt organic material; the content is limited to 18 weight % of unburnt carbon. The study was carried out in two phases. The aim of the first phase was to map the different techniques used for re-burning ash that are used in grate boilers today. The mapping was done through telephone interviews and comprises technical descriptions of the systems, gathering of operational know-how, installations costs and the effect of the systems on the amount of ash generated at the plants and the content of unburnt carbon in the ash. In order to accomplish a deeper technical and economical evaluation of ash re-burning systems, the second phase involved field studies at two plants. In addition screening tests were done to investigate the connection between the content of unburnt carbon and particle size. The potential of reducing the amount of circulated inorganic material by sieving the ash before bringing it back to the furnace could thereby be determined. 13 plants that utilize re-burning of ash were identified, of which two plants re-burn the bottom ash that floats up to the surface in the wet ash removal system. The remaining 11 plants re-burn fly ash. At three plants the fly ash is first separated in a mesh sieve or similar equipment and only the coarser fly ash is re-burnt. As the amount of bottom ash that surfaces in the wet ash-removal is relatively small

  2. Chemical composition and properties of ashes from combustion plants using Miscanthus as fuel.

    Science.gov (United States)

    Lanzerstorfer, Christof

    2017-04-01

    Miscanthus giganteus is one of the energy crops considered to show potential for a substantial contribution to sustainable energy production. In the literature there is little data available about the chemical composition of ashes from the combustion of Miscanthus and practically no data about their physical properties. However, for handling, treatment and utilization of the ashes this information is important. In this study ashes from two biomass combustion plants using Miscanthus as fuel were investigated. The density of the ashes was 2230±35kg/m(3), which was similar to the density of ashes from straw combustion. Also the bulk densities were close to those reported for straw ashes. The flowability of the ashes was a little worse than the flowability of ashes from wood combustion. The measured heavy metal concentrations were below the usual limits for utilization of the ashes as soil conditioner. The concentrations in the bottom ash were similar to those reported for ash from forest residue combustion plants. In comparison with cyclone fly ashes from forest residue combustion the measured heavy metal concentrations in the cyclone fly ash were considerably lower. Cl(-), S and Zn were enriched in the cyclone fly ash which is also known for ashes from wood combustion. In comparison with literature data obtained from Miscanthus plant material the concentrations of K, Cl(-) and S were lower. This can be attributed to the fact that the finest fly ash is not collected by the cyclone de-dusting system of the Miscanthus combustion plants. Copyright © 2016. Published by Elsevier B.V.

  3. Variability over time in the mutagenicity of ashes from municipal solid-waste incinerators.

    Science.gov (United States)

    Shane, B S; Gutenmann, W H; Lisk, D J

    1993-01-01

    Incineration of municipal solid waste as an alternative to its disposal in landfills has advantages such as volume reduction and generation of energy. However, both air emissions and the residual ash may pose environmental and human health hazards. The Ames mutagenicity assay was used to determine the mutagenicity of fly and bottom ash from two incinerators over time. This assay is an alternative to costly and time-consuming chemical analyses and is more realistic for the assessment of the best disposition of the ash i.e. whether it could pose a risk to handlers of the ash, whether it can be used in cement or as a fertilizer or whether it should be relegated to a landfill. The mutagenic potency of fly and bottom ash on a per g weight basis of material is similar. Furthermore, the variability over time in mutagenicity indicates that constant monitoring of incineration products and byproducts is essential.

  4. Behavior of Alkali Metals and Ash in a Low-Temperature Circulating Fluidized Bed (LTCFB) Gasifier

    DEFF Research Database (Denmark)

    Narayan, Vikas; Jensen, Peter Arendt; Henriksen, Ulrik Birk

    2016-01-01

    W and a 6 MW LTCFBgasifier. Of the total fuel ash entering the system, the largest fraction (40−50%) was retained in the secondary cyclone bottoms,while a lower amount (8−10%) was released as dust in the exit gas. Most of the alkali and alkaline earth metals were retained inthe solid ash, along with Si...... by the particle size and the cut size ofthe primary and secondary cyclones. A model accounting for the ash collection by the plant cyclones was shown to predict theproduct gas ash particle release reasonably well....

  5. Melting and Sintering of Ashes

    DEFF Research Database (Denmark)

    Hansen, Lone Aslaug

    1997-01-01

    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...... of melt in the investigated ashes has been determined as a function of temperature. Ash fusion results have been correlated to the chemical and mineralogical composition of the ashes, to results from a standard ash fusion test and to results from sintering experiments. Furthermore, the ash fusion results......-firing, the model only had a qualitative agreement with the measured ash deposit formation rates.Sintering measurements were carried out by means of compression strength testing of ash pellets. This method showed to not be applicable for the salt rich fly ash derived from straw combustion. For the fly ashes...

  6. Winter Bottom Trawl Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The standardized NEFSC Winter Bottom Trawl Survey was initiated in 1992 and covered offshore areas from the Mid-Atlantic to Georges Bank. Inshore strata were covered...

  7. Spring Bottom Trawl Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The standardized NEFSC Spring Bottom Trawl Survey was initiated in 1968 and covered an area from Cape Hatteras, NC, to Nova Scotia, Canada, at depths >27m....

  8. Fall Bottom Trawl Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The standardized NEFSC Fall Bottom Trawl Survey was initiated in 1963 and covered an area from Hudson Canyon, NY to Nova Scotia, Canada. Throughout the years,...

  9. Chemical properties of heavy metals in typical hospital waste incinerator ashes in China.

    Science.gov (United States)

    Zhao, Lijuan; Zhang, Fu-Shen; Wang, Kaisheng; Zhu, Jianxin

    2009-03-01

    Incineration has become the main mechanism for hospital waste (HW) disposal in China after the outbreak of Severe Acute Respiratory Syndrome (SARS) in 2003. However, little information is available on the chemical properties of the resulting ashes. In the present study, 22HW ash samples, including 14 samples of bottom ash and eight samples of fly ash, were collected from four typical HW incineration plants located across China. Chemical analysis indicated that the HW ashes contained large amounts of metal salts of Al, Ca, Fe, K, Mg, Na with a concentration range of 1.8-315gkg(-1). Furthermore, the ashes contained high concentrations of heavy metals such as Ag, As, Ba, Bi, Cd, Cr, Cu, Mn, Ni, Pb, Ti, Sb, Sn, Sr, Zn with a vast range of 1.1-121,411mgkg(-1), with higher concentrations found in the fly ash samples. Sequential extraction results showed that Ba, Cr, Ni and Sn are present in the residual fraction, while Cd existed in the exchangeable and carbonate fractions. As, Mn, Zn existed in the Fe-Mn oxide fraction, Pb was present in the Fe-Mn oxide and residual fractions, and Cu was present in the organic matter fraction. Furthermore, toxicity characteristic leaching procedure (TCLP) results indicated that leached amounts of Cd, Cu and Pb from almost all fly ash samples exceeded the USEPA regulated levels. A comparison between the HW ashes and municipal solid waste (MSW) ash showed that both HW bottom ash and fly ash contained higher concentrations of Ag, As, Bi, Cd, Cr, Cu, Pb, Ti, and Zn. This research provides critical information for appropriate HW incineration ash management plans.

  10. Pre-study - Straw ash in a nutrient loop; Foerstudie - Halmaska i ett kretslopp

    Energy Technology Data Exchange (ETDEWEB)

    Ottosson, Peter; Bjurstroem, Henrik; Johansson, Christina; Svensson, Sven-Erik; Mattsson, Jan Erik

    2009-03-15

    A sustainable production of energy crops requires that the loss of mineral nutrients when removing biomass is compensated naturally or by an addition of plant nutrients. Recycling ash is a natural way to satisfy this need arising after combustion of energy crops. In this pre-study, the prerequisites for recycling straw ash have been investigated. The Danish experience with spreading ash to fields and information in literature on the composition of ash have been collected and presented. Analysis of straw samples taken from four different places in Scania yielded information on cadmium and nutrient concentration in straw and in ash. A balance between removal of nutrient and cadmium with wheat straw and restoring them by recycling straw ash has been computed. Straw ash is a potassium fertiliser with some phosphorus and some liming effect. It is technically difficult to spread the small quantities of ash in solid form, ca 250 kg per hectare and year in average, which a pure recycling would require. It is easier to spread larger quantities, e.g. ca 1 ton per hectare every fourth year, which corresponds to spreading once in a four year crop rotation, but then one provides too much potassium if one considers the actual needs of the coming crops at that occasion, which could lead to potassium being leached out on light soils. Alternatively, one could spread only bottom ash, but this would lead to half of the potassium content not being recycled to agricultural soil and lost with the fly ash that is disposed of. If one spreads about 500 kg bottom ash per hectare every other year, which could be a suitable strategy to avoid overloading soils with potassium, the dose brought to 1 ha may be computed as: 4 - 10 kg phosphorus, 50 - 100 kg potassium, 5 - 15 kg sulphur, 4 - 8 kg magnesium, 0.1 - 0.3 kg manganese and 20 - 40 kg CaO. These basis of these calculations is the results from the analyses performed in this study. The cadmium concentration was significantly higher in wheat

  11. Particle size distribution of ashes and the behaviour of metals when firing Salix in a circulating fluidized bed boiler (CFB); Askans partikelfraktionsfoerdelning och metallernas beteende vid eldning av Salix i en CFB-panna

    Energy Technology Data Exchange (ETDEWEB)

    Sfiris, G.; Johansson, A. [Vattenfall Utveckling AB, Stockholm (Sweden); Valmari, T.; Kauppinen, E.; Pyykoenen, J.; Lyyraenen, J. [VTT Technical Research Centre of Finland, Espoo (Finland)

    1999-07-01

    This project is part of the Ash Recovery Programme aimed at establishing the environmental, technical and financial preconditions for returning wood ash to the forest. The programme is funded jointly by NUTEK, Sydkraft and Vattenfall. This report summarises the results of the experimental and modelling work to study the behaviour of the metals (especially Cd and K), after burning Salix in a 3-12 MW Circulating Fluidized Bed (CFB) boiler. The purpose of the study was to determine, using the experimental data, where cadmium and potassium condense, on what size particles they condense, and the decisive parameters governing these processes. Measurements of the fly ash particle size distribution carried out with a Berner Low Pressure Impactor (BLPI), coupled to a pre-cyclone. Samples were collected from three points: in the convection path at 650 deg C, after the convection path but before the secondary cyclone (160 deg C), and after the bag house (150 deg C). Wet chemical sampling was made for Cd, K, Zn and Pb, with three types of sampling equipment: collection of both particles and gas, collection of particles only, and analysis of the gas phase only. Analysis was made of samples from two places in the convection path (650 deg C and 250 deg C). Samples of bed material, bottom ash and fly ash have been subjected to scanning electron microscopy (SEM), and in addition a few fly ash particles, sampled after the convection path, were subjected to energy dispersive X-ray analysis (EDX). Based on experimental results, modelling work was carried out with an equilibrium model and with a general aerosol computer model ABC (Aerosol Behaviour in Combustion)

  12. Monitoring of test roads with MSWI bottom ash in the sub-base. Measurements with falling weight deflectometer on test structures in Malmoe and Umeaa. Analyses of ground water and leachate along test structures in Umeaa; Uppfoeljning av slaggrusprovvaegar. Fallviktsmaetning paa provstraeckor paa Toerringevaegen i Malmoe och Daavamyran i Umeaa. Grundvatten- och lakvattenanalyser paa provstraeckor vid Daavamyran i Umeaa

    Energy Technology Data Exchange (ETDEWEB)

    Arm, Maria; Larsson, Lennart; Tiberg, Charlotta; Lind, Bo; Arvidslund, Ola

    2008-12-15

    A number of test roads and test areas with processed municipal solid waste incinerator bottom ash, here called MSWI gravel, have been built in Sweden during the last 10-15 years. The main purpose of the projects reported here was to take advantage of the existing test roads to increase the knowledge of the long-term strength and environmental impact of MSWI gravel, when it is used as a road material. Two test roads with MSWI gravel in the sub-base were monitored through falling weight deflectometer (FWD) measurements and, for one of the roads, by means of sampling and analyses of groundwater and leachate within and along the road. The first road, constructed in 1998, is named Toerringevaegen and is situated outside Malmoe in the south of Sweden. The second road, Daava test road, was constructed in 2001 and is situated outside Umeaa in the north of Sweden. The roads were monitored regarding strength from 2004 to 2008 and Daava test road was also monitored regarding environmental impact from 2006 to 2008. For both roads, comparison was made over time and between the test sections with MSWI gravel and reference sections with crushed rock. Comparison was also made with results from previous studies on these test roads, resulting in a uniquely long monitoring period. The results from Toerringevaegen show that the road section with MSWI gravel in the sub-base retains its strength after several years. The three measurements performed at the Daava road revealed an initially decreasing strength and then a stabilisation. As in previous studies, the strength of the MSWI gravel was found to be about 70% of that of the crushed rock, which has to be taken into account in the design phase. It was concluded that regarding the strength properties MSWI gravel is suitable as sub-base material if the road is properly designed. It can also be used as a filling material, in embankments and as a capping layer. This confirms the conclusions from previous studies. The results from the

  13. Enrichment and particle size dependence of polonium and other naturally occurring radionuclides in coal ash.

    Science.gov (United States)

    Sahu, S K; Tiwari, M; Bhangare, R C; Pandit, G G

    2014-12-01

    Coal fired thermal power contributes 70% of power in India. Coal fired power generation results in huge amounts of fly ash and bottom ash of varying properties. Coal, which contains the naturally occurring radionuclides, on burning results in enrichment of these radionuclides in the ashes. In the present study, coal, bottom ash and fly ash samples collected from six coal-fired power plants in India were measured for (210)Po using alpha spectrometry and for natural U, (226)Ra, (232)Th and (40)K by an HPGe γ-ray spectrometer. (210)Po in fly ash ranged from 25.7 to 70 Bq/kg with a mean value of 40.5 Bq/kg. The range and mean activities of (238)U, (226)Ra, (232)Th, (40)K in fly ash were 38.5-101 (78.1), 60-105.7 (79), 20-125 (61.7) and 43.6-200 (100) Bq/kg respectively. Fly ash and bottom ash contains two to five times more natural radionuclides than feed coal. The results were compared with the available data from earlier studies in other countries. The effect of particle size on enrichment factor of the nuclides in fly ash was studied. (210)Po showed the largest size dependence with its concentration favoring the smaller particle size while (232)Th showed least size dependence. (238)U and (226)Ra showed behavior intermediate to that of (210)Po and (232)Th. Also the correlation between sulfur content of the feed coal and activity of (210)Po was investigated. Increased sulfur content in feed coal enhanced enrichment of (210)Po in ash. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Financial Benchmarking

    OpenAIRE

    2012-01-01

    This bachelor's thesis is focused on financial benchmarking of TULIPA PRAHA s.r.o. The aim of this work is to evaluate financial situation of the company, identify its strengths and weaknesses and to find out how efficient is the performance of this company in comparison with top companies within the same field by using INFA benchmarking diagnostic system of financial indicators. The theoretical part includes the characteristic of financial analysis, which financial benchmarking is based on a...

  15. Critical aspects of biomass ashes utilization in soils: Composition, leachability, PAH and PCDD/F.

    Science.gov (United States)

    Freire, Márcia; Lopes, Helena; Tarelho, Luís A C

    2015-12-01

    Bottom and fly ashes streams collected along a year in several biomass thermal plants were studied. The bulk composition of ashes and other chemical characteristics that may impact soil application showed a high variability depending on the ash stream, combustion technology and ash management practice at the power plants. The acid neutralization capacity (ANC) and metal's availability for leaching at fixed pH 7 and 4 was performed according with EA NEN 7371, as a quick evaluation method to provide information on the long-term behavior of ashes, regarding heavy metals and also plant nutrients release. Also the pH dependence leachability study was performed according to CEN/TS 14429 for predicting the leaching behavior under different scenarios. Leachability profiles were established between pH 3 and 12, allowing to distinguish different solubility control phenomena of toxic heavy metals (Cu, Cr, Mn, Ni, Zn, Pb) as well as other salts (Ca, K, Mg, Na, Cl). The ANC of fly ashes at pH 4 (3.6-9.6 molH(+)/kg) were higher than that observed for the bottom ashes (1.2-2.1 molH(+)/kg). Ashes were also characterized for persistent organic pollutants (POP), such as polycyclic aromatic hydrocarbons (PAH) and paradibenzodioxines and furanes (PCDD/F). Contents were found to be much higher in fly ash than in bottom ash streams. None of the PAH levels did reach the current national limit value of sewage sludge application in soils or the guide value for ash in north European countries. However, PCDD/F contents, which are not regulated, varied from non-detectable levels to high amounts, regardless the level of loss on ignition (LOI) or unburned carbon content in fly ashes. Given the current ash management practices and possible use of blends of bottom and fly ash streams as soil conditioners resembles clear the urgent need to regulate ash utilization in soils, incorporating limit values both for heavy metals, PAH and PCDD/F.

  16. Influence of feed and sampling systems on element partitioning in Kentucky fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Valentim, Bruno V. [Centro e Departamento de Geologia Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto (Portugal); Hower, James C. [University of Kentucky Center for Applied Energy Research (CAER), Lexington, Kentucky, 40511 (United States)

    2010-05-01

    Pentannual surveys of the production of coal combustion byproducts in Kentucky utility power plants, along with other studies in the intervening years has resulted in a large amount of data relating coal chemistry, fly ash (FA) chemistry, and, to a lesser degree, bottom ash chemistry. Therefore, this important collection of data enables to perform studies on a wide variety of fly ash types. The chemical classification, based on major oxides (acid, alkaline, and Fe{sub 2}O{sub 3}), of coal high-temperature ash (HTA) and FA from Kentucky Power Plants shows that the majority of the coal HTAs are Sialic, Sialic-Ferrisialic, and Ferrisialic. The FA classification not only depends of the coal HTA chemistry but also the ash-collection system and the sampling position, with the implications of flue gas temperature and ash particle size, within the system. (author)

  17. Utilization of ash products from combustion of shredded solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, P.F.; Mullen, J.F. (Energy Answers Corp, Albany, NY (US))

    1988-01-01

    One of the major problems with the siting, permitting, construction, and operation of a municipal solid waste-to- energy facility is the disposal of residues. As resource recovery increasingly becomes the disposal option of choice and necessity for municipalities across the country, the foci of environmental concerns has switched from groundwater contamination and inappropriate land use issues associated with landfilling, to air pollution control and residue disposal issues associated with waste combustion. It is suggested that the two separate ash streams can no longer reasonably be considered one and should be analyzed and treated separately, thereby increasing and enhancing the opportunity to recycle from the bottom ash (75 percent) and to focus on a reduced quantity of fly ash material (25 percent) for fixation and reuse or disposal. Such action would conform to the principles of, and the present regulatory trend towards waste minimization. However, there are many regulatory, institutional, and logistical barriers to such promising and seemingly simple waste reduction strategies. While the spirit of solid and hazardous waste legislation may emphasize waste minimization, ambiguities in the regulations have undermined the actual intent, creating an environment of confusion and indecisiveness with respect to treatment and disposal of ash from resource recovery facilities. This book reports on a research and development program to assess the feasibility and possible environmental impacts of utilizing a selected fraction of the bottom ash stream from processed refuse fuel-fired boilers as an aggregate substitute. The purpose of the research program is to develop data on the characteristics of bottom ash during exposure to rain and weathering in proposed applications.

  18. Charmed Bottom Baryon Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Zachary S; Detmold, William; Meinel, Stefan; Orginos, Kostas

    2014-11-01

    The spectrum of doubly and triply heavy baryons remains experimentally unexplored to a large extent. Although the detection of such heavy particle states may lie beyond the reach of exper- iments for some time, it is interesting compute this spectrum from QCD and compare results between lattice calculations and continuum theoretical models. Several lattice calculations ex- ist for both doubly and triply charmed as well as doubly and triply bottom baryons. Here, we present preliminary results from the first lattice calculation of doubly and triply heavy baryons including both charm and bottom quarks. We use domain wall fermions for 2+1 flavors (up down and strange) of sea and valence quarks, a relativistic heavy quark action for the charm quarks, and non-relativistic QCD for the heavier bottom quarks. We present preliminary results for the ground state spectrum.

  19. 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.

  20. The Laconia, New Hampshire Bottom, Ashi Paving Project. Volume 1: Environmental testing report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Bottom ash is the principal waste stream fro m the combustion of municipal solid waste (MSW). It is comprised of grate ash (97%), the slag material discharged at the end of the grate system and grate sffting (3%), the material that melts or falls through the grate structure. This project was conducted to demonstrate the feasibility of using municipal solid waste grate ash as an aggregate substitute in the construction of a pavement binder course for a portion of Rt. 3 in Laconia, New Hampshire. The research was conducted over a two year period during 1993 and 1994. This study is the culmination of an earlier two year characterization study between 1990 and 1992 that documented the physical and environmental characteristics of the bottom ash as it was produced at the Concord, N.H. waste-to-energy (WTE) facility and used in an asphaltic binder course. Together, these two studies provide a complete evaluation of the potential for using grate ash or bottom ash in asphalt binder course or as recycled asphalt pavement (RAP) in base courses in pavements.

  1. Comparison of Ash from PF and CFB Boilers and Behaviour of Ash in Ash Fields

    Science.gov (United States)

    Arro, H.; Pihu, T.; Prikk, A.; Rootamm, R.; Konist, A.

    Over 90% of electricity produced in Estonia is made by power plants firing local oil shale and 25% of the boilers are of the circulating fluidised bed (CFB) variety. In 2007 approximately 6.5 million tons of ash was acquired as a byproduct of using oil shale for energy production. Approximately 1.5 million tons of that was ash from CFB boilers. Such ash is deposited in ash fields by means ofhydro ash removal.

  2. 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....

  3. Laser bottom hole assembly

    Science.gov (United States)

    Underwood, Lance D; Norton, Ryan J; McKay, Ryan P; Mesnard, David R; Fraze, Jason D; Zediker, Mark S; Faircloth, Brian O

    2014-01-14

    There is provided for laser bottom hole assembly for providing a high power laser beam having greater than 5 kW of power for a laser mechanical drilling process to advance a borehole. This assembly utilizes a reverse Moineau motor type power section and provides a self-regulating system that addresses fluid flows relating to motive force, cooling and removal of cuttings.

  4. Utilization of municipal solid waste incineration ash in Portland cement clinker

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Charles Hoi King; Barford, John Patrick; McKay, Gordon [Hong Kong University of Science and Technology, Department of Chemical and Biomolecular Engineering, Hong Kong (China)

    2011-08-15

    Municipal solid waste incineration (MSWI) ash is used in part as raw materials for cement clinker production by taking advantage of the high contents of SiO{sub 2}, Al{sub 2}O{sub 3}, and CaO. It is necessary for environmental reasons to establish a material utilization system for the incineration waste ash residue instead of disposing these ashes into landfill. The aim of this paper is to study the feasibility of replacing clinker raw materials by waste ash residue for cement clinker production. MSWI bottom ash and MSWI fly ash are the main types of ashes being evaluated. The ashes were mixed into raw mixture with different portions of ash residue to produce cement clinker in a laboratory furnace at approximately 1400 C. X-ray diffraction and X-ray fluorescence techniques were used to analyze the phase chemistry and chemical composition of clinkers in order to compare these ash-based clinkers with commercial Portland cement clinker. (orig.)

  5. Ash Properties of Alternative Biomass

    DEFF Research Database (Denmark)

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

    2009-01-01

    The ash behavior during suspension firing of 12 alternative solid biofuels, such as pectin waste, mash from a beer brewery, or waste from cigarette production have been studied and compared to wood and straw ash behavior. Laboratory suspension firing tests were performed on an entrained flow...... 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....

  6. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    Science.gov (United States)

    Palaniappan, Jayanthi

    2017-04-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  7. Financial Education

    OpenAIRE

    Udo Reifner; Anne Schelhowe

    2010-01-01

    New, more or better financial education and financial literacy programmes should lead to improved financial capability, knowledge and outcomes. Yet we do not even know which terminology is most suitable for those projects who all intend to give an answer to a question which is less than clear. What is meant by the term “financial education”? Why did the “demand” for financial education suddenly increase? Have the numerous tasks which consumers in a modern society have to fulfill created this ...

  8. Environmental impacts of the Tennessee Valley Authority Kingston coal ash spill. 2. Effect of coal ash on methylmercury in historically contaminated river sediments.

    Science.gov (United States)

    Deonarine, Amrika; Bartov, Gideon; Johnson, Thomas M; Ruhl, Laura; Vengosh, Avner; Hsu-Kim, Heileen

    2013-02-19

    The Tennessee Valley Authority Kingston coal ash spill in December 2008 deposited approximately 4.1 million m(3) of fly ash and bottom ash into the Emory and Clinch River system (Harriman, Tennessee, U.S.A.). The objective of this study was to investigate the impact of the ash on surface water and sediment quality over an eighteen month period after the spill, with a specific focus on mercury and methylmercury in sediments. Our results indicated that surface water quality was not impaired with respect to total mercury concentrations. However, in the sediments of the Emory River near the coal ash spill, total mercury concentrations were 3- to 4-times greater than sediments several miles upstream of the ash spill. Similarly, methylmercury content in the Emory and Clinch River sediments near the ash spill were slightly elevated (up to a factor of 3) at certain locations compared to upstream sediments. Up to 2% of the total mercury in sediments containing coal ash was present as methylmercury. Mercury isotope composition and sediment geochemical data suggested that elevated methylmercury concentrations occurred in regions where native sediments were mixed with coal ash (e.g., less than 28% as coal ash in the Emory River). This coal ash may have provided substrates (such as sulfate) that stimulated biomethylation of mercury. The production of methylmercury in these areas is a concern because this neurotoxic organomercury compound can be highly bioaccumulative. Future risk assessments of coal ash spills should consider not only the leaching potential of mercury from the wastes but also the potential for methylmercury production in receiving waters.

  9. MAT 126 ASH Course Tutorial / Tutorialoutlet

    OpenAIRE

    stylia

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   MAT 126 Week 1 DQ 1 (Ash) MAT 126 Week 1 Quiz (Ash) MAT 126 Week 1 Written Assignment (Arithmetic and geometric sequence) (Ash) MAT 126 Week 2 DQ 1 (Ash) MAT 126 Week 2 DQ 2 (Ash) MAT 126 Week 2 Assignment Is It Fat Free (Ash) MAT 126 Week 2 Quiz (Ash) MAT 126 Week 3 DQ 1 (Ash) MAT 126 Week 3 DQ 2 (Ash) MAT 126 Week 3 Assignment Quadratic Equations (Ash) MAT 126 Week 3 Quiz (Ash) MAT 126...

  10. Morphological and Strength Properties of Tanjung Bin Coal Ash Mixtures for applied in Geotechnical Engineering Work

    Directory of Open Access Journals (Sweden)

    Abd. Rahim Awang

    2012-01-01

    Full Text Available In Malaysia, coal has been used as a raw material to generate electricity since 1988. In the past, most of the wastage of coal burning especially the bottom ash was not managed properly as it was dumped in the waste pond and accumulated drastically.This paper focuses on some properties of coal ash mixtures (fly  ash and bottom ash mixtures from Tanjung Bin power plant. The characteristics studied were morphological properties, compaction behaviour and strength properties. Strength properties of coal ash mixtures are carried out by conducting direct shear test and unconfined compression test. Besides, morphology and mineralogy of coal ash mixtures are studied using scanning electron microscope (SEM and x-ray diffraction (XRD. The coal ash mixtures were compacted at 95% of maximum dry density, sealed and cured for 0, 14, and 28 days before they were analysed for shear strength, morphological and mineralogical analyses. The shear strength of coal ash mixtures varied depending on the fly ash compositions. The maximum shear strength was obtained at mixture with 50%FA: 50%BA and the value increased with curing periods. The friction angle obtained ranged from 27° to 37°. Morphological analysis showed that the number of irregular shaped particles increased confirming change in material type with curing period. From mineralogical analysis, the crystalline compounds present in Tanjung Bin coal ash were Mullite, Quartz, Calcium Phosphide, Calcite, Cristobalite and Hematite. It can be concluded that the coal ash mixtures can advantageously be applied in the construction of embankments, roads, reclamation and fill behind retaining structures.

  11. Radiolarian zonation and volcanic ash layers in two Quaternary sediment cores from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Gupta, S.M.

    and redistribution of Pliocene taxa by a bottom water current (probably Antarctic Bottom Water Current). Volcanic ash layers of apparently about 20,000; 30,000 - 40,000; 80,000; 340,000 and younger than 4000,000 years are also recognised, which suggest suboceanic...

  12. A plea for Global Health Action bottom-up

    Directory of Open Access Journals (Sweden)

    Ulrich Laaser

    2016-10-01

    Full Text Available This opinion piece focuses on global health action by hands-on bottom-up practice: Initiation of an organizational framework and securing financial efficiency are – however - essential, both clearly a domain of well trained public health professionals. Examples of action are cited in the four main areas of global threats: planetary climate change, global divides and inequity, global insecurity and violent conflicts, global instability and financial crises. In conclusion a stable health systems policy framework would greatly enhance success. However, such organisational framework dries out if not linked to public debates channelling fresh thoughts and controversial proposals: the structural stabilisation is essential but has to serve not to dominate bottom-up activities. In other words a horizontal management is required, a balanced equilibrium between bottom-up initiative and top-down support. Last not least rewarding voluntary and charity work by public acknowledgement is essential.

  13. Selective mobilization of critical elements in incineration ashes; Selektiv mobilisering av kritiska element hos energiaskor

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Malin; Herrmann, Inga; Ecke, Holger [Luleaa Univ. of Technology (Sweden); Sjoeblom, Rolf [TEKEDO AB, Nykoeping (Sweden)

    2005-05-01

    In the project SMAK, the selective mobilization of critical elements in ashes was studied. Non-hazardous bottom ash from Daava kraftvaermeverk, Umeaa, and hazardous fly ash from Hoegdalenverket, Stockholm, line P6 were investigated. Sb, Mo, Cu, Cr and Cl{sup -} were identified as critical elements in the bottom ash since these elements exceeded the limit values for acceptance on landfills as inert waste according to the Council decision on acceptance criteria at landfills. Critical elements in the fly ash were Cr, Se, Pb and Cl{sup -}, these elements exceeded the limit values for acceptance on landfills as non-hazardous waste. The mobilization of the critical elements was studied in experiments performed according to a reduced 2{sup 6-1} factorial design with three centerpoints. Factors in the experiments were ultrasonic pre-treatment, pre-treatment with carbonation, L/S-ratio, pH, time and temperature. Empirical models of the mobilization were used to identify the optimal factor setting ensuring sufficient mobilization of critical elements, i.e. to achieve a solid residue meeting non-hazardous and inert landfill criteria for fly ash and bottom ash, respectively. No ultrasonic treatment, pre-treatment with carbonation, L/Sratio 5, pH 12, time 2h and temperature at 20 deg C were identified as optimal factor setting for the bottom ash. For the fly ash, no ultrasonic treatment, no pre-treatment with carbonation, L/S-ratio 5, pH 7, time 2h and temperature at 20 deg C were identified as optimal factor setting. The treatment with optimal factor settings did not change the classification according to the Council decision on acceptance criteria at landfills of neither ash. For the bottom ash, Sb, Mo and Cr exceeded the limit values for landfilling as inert waste according to the Council decision on acceptance criteria at landfills. Only Cr exceeded the limit value for landfilling the fly ash as non-hazardous waste. According to the Waste Decree (Avfallsfoerordningen) both

  14. FINANCIAL MECHANISMS OF FINANCIAL CRISES

    Directory of Open Access Journals (Sweden)

    Ivan LUCHIAN

    2016-07-01

    Full Text Available The actuality of this article is determined by the need to demonstrate that financial crisis is not just an issue of economic disaster caused by contagion effect of financial cataclysm, expressed in national currency depreciation, depletion of foreign exchange reserves, mass bankruptcy of financial institutions, non-market entities insolvency and impossibility of sovereign debt servicing, but a special investment opportunity with associated characteristics of profitability. Central aims of article is research of financial crisis essence, investment mechanisms linked to existing fundamental laws of its conduct and determination of investment opportunities manifested in various segments of financial market and related sectors. Main research methods were: systemic analysis, statistical analysis, monographic and logic synthesis, etc. Main scientific results obtained in the article, due to research are to identify, analyze and demonstrate investment opportunities of international financial crisis and financial crises in Moldova.

  15. Hydration of fly ash cement

    Energy Technology Data Exchange (ETDEWEB)

    Etsuo Sakai; Shigeyoshi Miyahara; Shigenari Ohsawa; Seung-Heun Lee; Masaki Daimon [Tokyo Institute of Technology, Tokyo (Japan). Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering

    2005-06-01

    It is necessary to establish the material design system for the utilization of large amounts of fly ash as blended cement instead of disposing of it as a waste. Cement blended with fly ash is also required as a countermeasure to reduce the amount of CO{sub 2} generation. In this study, the influences of the glass content and the basicity of glass phase on the hydration of fly ash cement were clarified and hydration over a long curing time was characterized. Two kinds of fly ash with different glass content, one with 38.2% and another with 76.6%, were used. The hydration ratio of fly ash was increased by increasing the glass content in fly ash in the specimens cured for 270 days. When the glass content of fly ash is low, the basicity of glass phase tends to decrease. Reactivity of fly ash is controlled by the basicity of the glass phase in fly ash during a period from 28 to 270 days. However, at an age of 360 days, the reaction ratios of fly ash show almost identical values with different glass contents. Fly ash also affected the hydration of cement clinker minerals in fly ash cement. While the hydration of alite was accelerated, that of belite was retarded at a late stage.

  16. 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.

  17. Electrodialytic treatment of fly ash

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Pedersen, Anne Juul; Kirkelund, Gunvor Marie

    Heavy metals are removed from the fly ashes by an electrodialytic treatment with the aim of up-grading the ashes for reuse in stead of disposal in landfill.A great potential for upgrading of bio- and waste incineration ashes by electrodialytic treatment exists. In the future, the applicability...

  18. Fly ash as an adsorbent for textile dyes from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Khan, B.; Gupta, P.; Jala, S.; Goyal, D. [Thapar Institute of Engineering and Technology, Patiala (India). Dept. of Biotechnology and Environmental Sciences

    2003-07-01

    Fly ash is a solid waste generated as a result of combustion of coal and is of three types: the ESP (electrostatic precipitator) ash, bottom ash, and pond ash. Decolorization of two triphenylmethane dyes (crystal violet and malachite green) and one azo dye (congo red) was tried using the ESP fly ash in bath and column mode. Decolorization of 20 ppm of crystal violet and 100 ppm of malachite green occurred to the extent of 86% and 84% respectively, in batch mode. In columns packed with fly ash, 100 ppm of inlet solution of congo red and decolorized by 84%, at a flow rate of 2.0 ml/hour of packed bed column. When fly ash was mixed with activated charcoal in the ratio of 8:2, almost complete decolorization of the dye solution was observed, and the heavy metal content in the resulting colourless effluent was within permissible limits. This suggested that a combination of fly ash and activated charcoal can lead to replacement of nearly 80% of the activated charcoal, which can be a direct saving in operation costs along with gainful utilization of fly ash. 21 refs., 1 fig., 2 tabs.

  19. 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

  20. Co-financing of bottom-up approaches towards Broadband Infrastructure Development

    DEFF Research Database (Denmark)

    Williams, Idongesit

    2016-01-01

    Bottom – up Broadband infrastructure development facilitated by the civil societies and social enterprises are on the increase. However, the problem plaguing the development of these bottom-up approaches in developing countries is the financial capacity to expand their small networks into larger...

  1. Ash formation, transformations and deposition during fluidized bed combustion and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Kauppinen, E.; Lind, T.; Kurkela, J.; Latva-Somppi, J.; Lyyraenen, J.; Valmari, T. [VTT Chemical Technology, Espoo (Finland). Aerosol Technology Group

    1998-12-31

    In this work, ash formation and transformations as well as bed agglomeration and fly ash deposition onto the heat exchanger tubes during fluidised bed combustion and gasification were studied using experimental methods and chemical equilibrium calculations. The fuels were coal and pulp and paper mill sludges as well as different wood-based waste materials. The volatilized heavy metal behaviour during pressurized combustion and gasification was studied using chemical equilibrium calculations. The classification of trace elements into four groups presented in this report matched well with the former studies. The release of ash-forming compounds during pyrolysis was studied experimentally in a heated grid reactor. Very small fractions of Si, Al, Fe, Ca, Mg, Na, and K were released from the biomass fuels, peat, and coals during pyrolysis at 900 deg C. Bottom ash during combustion of biomass fuels was found to be formed from bed material and ash-forming compounds. Ash-forming compounds were found to adhere to the bed material by two mechanisms: (i) by deposition of the non-volatile ash compounds as particles onto the bed particle surface, and (ii) by chemical reactions of the volatile ash compounds, e.g., K and Pb, with the bed particles. The size distributions of the fly ash particles were bimodal. The fine mode particles (Dp < 1 {mu}m) were formed by nucleation of the volatilised refractory oxides, e.g., SiO{sub 2}. The nucleated particles grew further by coagulation and condensation of the volatile ash compounds. The coarse fly ash fraction (Dp > 1 {mu}m) was formed from the non-volatile ash compounds, e.g., Ca and Si. The coarse mode particles were agglomerated and irregular in shape. During sludge combustion, the fly ash was mostly in the supermicron size range. This is beneficial for conventional flue gas cleaning devices that are most effective in this particle size. This is especially true for paper mill sludges, producing negligible concentrations of submicron

  2. Financial mathematics

    CERN Document Server

    Jothi, A Lenin

    2009-01-01

    Financial services, particularly banking and insurance services is the prominent sector for the development of a nation. After the liberalisation of financial sector in India, the scope of getting career opportunities has been widened. It is heartening to note that various universities in India have introduced professional courses on banking and insurance. A new field of applied mathematics has come into prominence under the name of Financial Mathematics. Financial mathematics has attained much importance in the recent years because of the role played by mathematical concepts in decision - m

  3. A bottom hole motor

    Energy Technology Data Exchange (ETDEWEB)

    Kibishcher, G.B.; Karpenko, V.K.; Pogorelov, V.P.

    1982-01-01

    A bottom hole motor is proposed which includes a body, a push rod with a piston, a spindle, a mechanism for converting the reciprocal movement of the piston into rotation of the shaft and pump and drain cavities. In order to simplify the design the push rod is made with radial openings above and below the piston, while the shaft is made with two longitudinal channels at the level of the radial openings of the push rod on the diametrically opposite sides. The cavity of one channel is constantly connected with the pump cavity, while the other is permanently connected with the drain cavity.

  4. MGT 330 ASH Course Tutorial / Tutorialoutlet

    OpenAIRE

    alfoniz

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   MGT 330 Week 1 Individual Assignment Functions of Management Paper (Ash) MGT 330 Week 1 DQ 1 (Ash) MGT 330 Week 1 DQ 2 (Ash) MGT 330 Week 1 DQ 3 (Ash) MGT 330 Week 1 Summary (Ash) MGT 330 Week 2 Team Assignment External Internal Factors Paper (Ash) MGT 330 Week 2 Individual Assignment Delegation (Ash) MGT 330 Week 2 Summary (Ash) MGT 330 Week 2 DQ 1 (Ash) MGT 330 Week 2 DQ 2 (Ash) MGT 330 W...

  5. Experimental studies on pulp and paper mill sludge ash behavior in fluidized bed combustors

    Energy Technology Data Exchange (ETDEWEB)

    Latva-Somppi, J. [VTT Chemical Technology, Espoo (Finland). Process Technology

    1998-11-01

    Ash formation during the fluidized bed combustion (FBC) of pulp and paper mill sludges has been experimentally studied on an industrial and bench scale. The methods included aerosol measurements, chemical and crystalline composition analyses, thermogravimetry and electron microscopy. Fly ash mass and number size distributions and elemental enrichment in submicron particles and bottom ash were measured. Fly ash, bottom ash and ash deposits were characterized and their formation mechanisms are discussed. During combustion the fine paper-making additives in sludge, clay minerals and calcite, sintered fanning porous agglomerates. The fly ash mass mean size was 7.5 - 15 lam and the supermicron particles included 93.6 - 97.3 % of the fly ash. Condensation of the volatilized inorganic species formed spherical submicron particles in the fly ash. Their mass concentration was almost negligible when co-firing paper mill sludges and wood. This suggests that the fraction of the volatilized inorganic species in the paper mill sludges was low. Results from pulp mill sludge and bark co-firing were different. A clear mass mode below 0.3 pm, presenting 2.2 - 5.0 weight-% of the fly ash was detected. The condensed species included K, Na, S and Cl. Their mass fraction was higher in the pulp mill sludge than in the paper mill sludge. Evidently this resulted in increased volatilization and formation of condensed particles. The following trace elements were enriched in the submicron ash during pulp mill sludge and wood co-firing: As, Cd, Rb and Pb. The main part of the volatile species was, however, captured in the bulk ash. Presumably, this was due to the high surface area concentration in the bulk ash. Sludge moisture was observed to reduce the inorganic species volatilization. Probably steam vaporization from the wet sludge through the burning layer decreased combustion temperatures on char surface and less char was produced. Hence, the volatilization of ash forming species was

  6. “Technical Properties of Pond Ash - Clay Fired Bricks – An Experimental Study”

    Directory of Open Access Journals (Sweden)

    Prashant G. Sonawane

    2013-09-01

    Full Text Available In the thermal power plants the coal is burnt to heat the water for making the steam, which in turn is used to run the turbines. The pond ash is a waste product from the boilers. It is mainly obtained from the wet disposal of the fly ash, which when get mixed with bottom ash is disposed off in large pond or dykes as slurry. The pond ash is being generated in an alarming rate. The generation of the pond ash is posing a lot of threat to environment and thus its sustainable management has become the thrust area in engineering research. As the pond ash is relatively coarse and the dissolvable alkalies present in it are washed with water, its pozzolanic reactivity becomes low and hence it is not preferred as part replacement of cement in concrete as in the case of fly ash. In this research work an attempt is made to find out the possibility of using pond ash in burnt clay bricks. The part of the clay is replaced by pond ash in different composition and the bricks are made in conventional method at a brick manufacturing plant. The bricks are fired in a traditional way as per usual practice in the area and the final products with different composition of pond ash are tested in laboratory; for tolerance in dimension, water absorption, compressive strength, initial rate of absorption and weathering. The results of all the tests on brick samples with different % of pond ash are compared with clay bricks and the effect on different characteristics of bricks due to addition of pond ash are studied.

  7. Financial Literacy, Financial Education, and Economic Outcomes

    Science.gov (United States)

    Hastings, Justine S.; Madrian, Brigitte C.; Skimmyhorn, William L.

    2013-01-01

    In this article, we review the literature on financial literacy, financial education, and consumer financial outcomes. We consider how financial literacy is measured in the current literature and examine how well the existing literature addresses whether financial education improves financial literacy or personal financial outcomes. We discuss the…

  8. Financial Literacy, Financial Education, and Economic Outcomes

    Science.gov (United States)

    Hastings, Justine S.; Madrian, Brigitte C.; Skimmyhorn, William L.

    2013-01-01

    In this article, we review the literature on financial literacy, financial education, and consumer financial outcomes. We consider how financial literacy is measured in the current literature and examine how well the existing literature addresses whether financial education improves financial literacy or personal financial outcomes. We discuss the…

  9. MSWI boiler fly ashes: magnetic separation for material recovery.

    Science.gov (United States)

    De Boom, Aurore; Degrez, Marc; Hubaux, Paul; Lucion, Christian

    2011-07-01

    Nowadays, ferrous materials are usually recovered from Municipal Solid Waste Incineration (MSWI) bottom ash by magnetic separation. To our knowledge, such a physical technique has not been applied so far to other MSWI residues. This study focuses thus on the applicability of magnetic separation on boiler fly ashes (BFA). Different types of magnet are used to extract the magnetic particles. We investigate the magnetic particle composition, as well as their leaching behaviour (EN 12457-1 leaching test). The magnetic particles present higher Cr, Fe, Mn and Ni concentration than the non-magnetic (NM) fraction. Magnetic separation does not improve the leachability of the NM fraction. To approximate industrial conditions, magnetic separation is also applied to BFA mixed with water by using a pilot. BFA magnetic separation is economically evaluated. This study globally shows that it is possible to extract some magnetic particles from MSWI boiler fly ashes. However, the magnetic particles only represent from 23 to 120 g/kg of the BFA and, though they are enriched in Fe, are composed of similar elements to the raw ashes. The industrial application of magnetic separation would only be profitable if large amounts of ashes were treated (more than 15 kt/y), and the process should be ideally completed by other recovery methods or advanced treatments.

  10. Effect of coal ash disposal upon an unconfined alluvial system

    Energy Technology Data Exchange (ETDEWEB)

    Shergill, B.S.; Sendlein, L.V.A. (Univ. of Kentucky, Lexington, KY (United States). Dept. of Geological Sciences); Dinger, J.S. (Univ. of Kentucky, Lexington, KY (United States). Kentucky Geological Survey)

    1992-01-01

    Fly and bottom ash from coal combustion has been disposed in four ash ponds in an alluvial valley. Three of the ash ponds are receiving ash and one was filled and closed. Twenty eight monitoring wells ranging in depth from 10 feet to 65 feet have been installed at the site to study groundwater flow and chemistry. Hydraulic heads are influenced by the stage of the Kentucky River, and the flow direction is vertical below the ash ponds and predominantly horizontal a short distance from the pond all the way to the river. Three different groundwater flow zones were observed and have unique water chemistry. The deep zone (near bedrock) has a low Eh (< [minus]80), and high concentration of Fe, ammonia nitrogen, below detection sulfate values (< 5 mg/l) and trace metals. The age of the deep groundwater as determined by tritium analyses is between 20 to 30 years old (5.68 TU). The intermediate groundwater zone (from ash pond) has relatively higher Eh (> 100) and lower concentrations of Fe and ammonia nitrogen, median sulfate concentration (114 mg/l), and arsenic is below detection limits. The shallow groundwater zone is through the closed out ash point and has higher concentrations of nearly all cations and anions, including sulfate (888 mg/l) and arsenic (exists as arsenite) at concentration of 0.9 mg/l, low Eh (< [minus]100), and high pH. When shallow flow enters the alluvium, the sulfate are attenuated by sulfate reduction and this results in high bicarbonate values. Saturation indices (SI) as calculated by the geochemical model, MINTEQA2, indicate that deep and intermediate groundwater are unsaturated and shallow groundwater is at or near equilibrium with respect to calcite, dolomite, and gypsum.

  11. Volcanic ash melting under conditions relevant to ash turbine interactions.

    Science.gov (United States)

    Song, Wenjia; Lavallée, Yan; Hess, Kai-Uwe; Kueppers, Ulrich; Cimarelli, Corrado; Dingwell, Donald B

    2016-03-02

    The ingestion of volcanic ash by jet engines is widely recognized as a potentially fatal hazard for aircraft operation. The high temperatures (1,200-2,000 °C) typical of jet engines exacerbate the impact of ash by provoking its melting and sticking to turbine parts. Estimation of this potential hazard is complicated by the fact that chemical composition, which affects the temperature at which volcanic ash becomes liquid, can vary widely amongst volcanoes. Here, based on experiments, we parameterize ash behaviour and develop a model to predict melting and sticking conditions for its global compositional range. The results of our experiments confirm that the common use of sand or dust proxy is wholly inadequate for the prediction of the behaviour of volcanic ash, leading to overestimates of sticking temperature and thus severe underestimates of the thermal hazard. Our model can be used to assess the deposition probability of volcanic ash in jet engines.

  12. ASSESSMENT OF THE USE FOR FERTILISATION PURPOSES INCINERATION ASH PELLETS USING GASIFICATION BURNER LESTER

    Directory of Open Access Journals (Sweden)

    Marzena Gibczyńska

    2016-12-01

    Full Text Available The use of biomass in system energetics for the purpose of increasing the share of renewable energy sources in the overall energy mix by biomass and coal co-combustion is not an optimal solution in the light of previous experience in Poland. It is appropriate to develop local biomass market for energy purposes as a basis for future distributed energy generation based on biomass. This solution facilitates the use of ash from biomass combustion for plant fertilisation. The present paper concerns the assessment of the use of ash from combustion of pellets in an innovative gasifying pellet burner – LESTER type, for soil fertilisation. The paper presents the analysis of the content of macro- and microelements in ash against the chemical composition of pellets in relation to permissible contents in fertilisers. The content of phosphorus, potassium, calcium and magnesium in bottom and fly ash from combustion of wood pellet and rye straw in LESTER gasifying burner validates the use of this material for soil fertilisation purposes. However, due to low nitrogen content – comparable to that found in soil, the material is not to be considered as fertiliser supplying this macroelement to soil. The analysed bottom ash used for fertilisation meets the conditions set out in the Regulation of the Minister of Environment of 9 September 2002. However, fly ash should be used with considerable caution due to high content of iron, zinc and nickel. The yield of bottom ash is several times higher than that of fly ash, therefore the possibility of its use in the form of mixtures in adequate proportions should be considered.

  13. Full-scale ash deposition measurements at Avedøre Power Plant unit 2 during suspension-firing of wood with and without coal ash addition

    DEFF Research Database (Denmark)

    Wu, Hao; Shafique Bashir, Muhammad; Jensen, Peter Arendt

    The formation of deposits during suspension-firing of wood at Avedøre Power Plant unit 2 (AVV2) was studied by using an advanced deposit probe system. The tests were conducted both with and without coal ash addition, and at two different locations with flue gas temperatures of 1250-1300 oC and 750......-800 oC respectively. The deposit formation process was studied quantitatively though the mass uptake data from the load-cell of the probe, while camera pictures were used to qualitatively verify the obtained mass uptake data and to explain the deposit buildup/shedding mechanisms. The collected deposits...... along with the fly ash and bottom ash from the plant were characterized extensively by SEM-EDS, ICP-OES/IC and XRD. Based on the results from the present work, the deposit formation and shedding mechanisms under different operational conditions were proposed and discussed. The influence of coal ash...

  14. MGT 401 ASH Course Tutorial / Tutorialoutlet

    OpenAIRE

    kennith

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   MGT 401 Week 1 Individual Assignment Strategic Management Process Paper (Ash) MGT 401 Week 1 Class Activity Week 1 (Ash) MGT 401 Week 1 DQ 1 (Ash) MGT 401 Week 1 DQ 2 (Ash) MGT 401 Week 2 Learning Team Business Model Comparison Example (Ash) MGT 401 Week 2 DQ 1 (Ash) MGT 401 Week 2 DQ 2 (Ash) MGT 401 Week 2 Class Activity (Ash) MGT 401 Week 3 Individual Assignment Business Plan Evaluation (Ash) ...

  15. Melting Behavior of Volcanic Ash relevant to Aviation Ash Hazard

    Science.gov (United States)

    Song, W.; Hess, K.; Lavallee, Y.; Cimarelli, C.; Dingwell, D. B.

    2013-12-01

    Volcanic ash is one of the major hazards caused by volcanic eruptions. In particular, the threat to aviation from airborne volcanic ash has been widely recognized and documented. In the past 12 years, more than 60 modern jet airplanes, mostly jumbo jets, have been damaged by drifting clouds of volcanic ash that have contaminated air routes and airport facilities. Seven of these encounters are known to have caused in-flight loss of engine power to jumbo jets carrying a total of more than 2000 passengers. The primary cause of engine thrust loss is that the glass in volcanic ash particles is generated at temperatures far lower than the temperatures in the combustion chamber of a jet engine ( i.e. > 1600 oC) and when the molten volcanic ash particles leave this hottest section of the engine, the resolidified molten volcanic ash particles will be accumulated on the turbine nozzle guide vanes, which reduced the effective flow of air through the engine ultimately causing failure. Thus, it is essential to investigate the melting process and subsequent deposition behavior of volcanic ash under gas turbine conditions. Although few research studies that investigated the deposition behavior of volcanic ash at the high temperature are to be found in public domain, to the best our knowledge, no work addresses the formation of molten volcanic ash. In this work, volcanic ash produced by Santiaguito volcano in Guatemala in November 8, 2012 was selected for study because of their recent activity and potential hazard to aircraft safety. We used the method of accessing the behavior of deposit-forming impurities in high temperature boiler plants on the basis of observations of the change in shape and size of a cylindrical coal ash to study the sintering and fusion phenomena as well as determine the volcanic ash melting behavior by using characteristic temperatures by means of hot stage microscope (HSM), different thermal analysis (DTA) and Thermal Gravimetric Analysis (TGA) to

  16. Bottom-Up Earley Deduction

    CERN Document Server

    Erbach, G

    1995-01-01

    We propose a bottom-up variant of Earley deduction. Bottom-up deduction is preferable to top-down deduction because it allows incremental processing (even for head-driven grammars), it is data-driven, no subsumption check is needed, and preference values attached to lexical items can be used to guide best-first search. We discuss the scanning step for bottom-up Earley deduction and indexing schemes that help avoid useless deduction steps.

  17. Bioaccessibility and health risk of heavy metals in ash from the incineration of different e-waste residues.

    Science.gov (United States)

    Tao, Xiao-Qing; Shen, Dong-Sheng; Shentu, Jia-Li; Long, Yu-Yang; Feng, Yi-Jian; Shen, Chen-Chao

    2015-03-01

    Ash from incinerated e-waste dismantling residues (EDR) may cause significant health risks to people through ingestion, inhalation, and dermal contact exposure pathways. Ashes of four classified e-waste types generated by an incineration plant in Zhejiang, China were collected. Total contents and the bioaccessibilities of Cd, Cu, Ni, Pb, and Zn in ashes were measured to provide crucial information to evaluate the health risks for incinerator workers and children living in vicinity. Compared to raw e-waste in mixture, ash was metal-enriched by category incinerated. However, the physiologically based extraction test (PBET) indicates the bioaccessibilities of Ni, Pb, and Zn were less than 50 %. Obviously, bioaccessibilities need to be considered in noncancer risk estimate. Total and PBET-extractable contents of metal, except for Pb, were significantly correlated with the pH of the ash. Noncancer risks of ash from different incinerator parts decreased in the order bag filter ash (BFA) > cyclone separator ash (CFA) > bottom ash (BA). The hazard quotient for exposure to ash were decreased as ingestion > dermal contact > inhalation. Pb in ingested ash dominated (>80 %) noncancer risks, and children had high chronic risks from Pb (hazard index >10). Carcinogenic risks from exposure to ash were under the acceptable level (<10(-6)) both for children and workers. Exposure to ash increased workers' cancer risks and children's noncancer risks. Given the risk estimate is complex including toxicity/bioaccessibility of metals, the ways of exposure, and many uncertainties, further researches are required before any definite decisions on mitigating health risks caused by exposure to EDR incinerated ash are made.

  18. Ash in the Soil System

    Science.gov (United States)

    Pereira, P.

    2012-04-01

    Ash is the organic and inorganic residue produced by combustion, under laboratory and field conditions. This definition is far away to be accepted. Some researchers consider ash only as the inorganic part, others include also the material not completely combusted as charcoal or biochar. There is a need to have a convergence about this question and define clear "what means ash". After the fire and after spread ash onto soil surface, soil properties can be substantially changed depending on ash properties, that can be different according to the burned residue (e.g wood, coal, solid waste, peppermill, animal residues), material treatment before burning, time of exposition and storage conditions. Ash produced in boilers is different from the produced in fires because of the material diferent propertie and burning conditions. In addition, the ash produced in boilers is frequently treated (e.g pelletization, granulation, self curing) previously to application, to reduce the negative effects on soil (e.g rapid increase of pH, mycorrhiza, fine roots of trees and microfauna). These treatments normally reduce the rate of nutrients dissolution. In fires this does not happen. Thus the implications on soil properties are logically different. Depending on the combustion temperature and/or severity, ash could have different physical (e.g texture, wettability) and chemical properties (e.g amount and type of total and leached nutrients) and this will have implications on soil. Ash can increase and decrease soil aggregation, wettablity and water retention, bulk density, runoff and water infiltration. Normally, ash increases soil pH, Electrical Conductivity, and the amount of some basic nutrients as calcium, magnesium, sodium and potassium. However it is also a potential source of heavy metals, especially if ash pH is low. However the effect of ash on soil in space and time depends especially of the ash amount and characteristics, fire temperature, severity, topography, aspect

  19. CFD modeling of stripper ash cooler of circulating fluidized bed boiler

    Directory of Open Access Journals (Sweden)

    Ravi Inder Singh

    2016-09-01

    Full Text Available The stable operation of a bottom ash cooler is vital for the operation of the circulating fluidized bed boiler. To assess, the stability of the ash cooler, it is important to have a thorough understanding of the flow behaviour. Although, many experimental results been reported in literature, CFD modelling of the ash cooler has not been carried out. In this paper, the transient computational analysis of a novel stripper ash cooler has been carried out using the Eulerian–Eulerian multiphase approach. The phase coupled SIMPLE algorithm has been used to solve the multiphase equations and the Gidaspow drag model has been employed to model the interaction between the fluidized air and ash. Two cases have been analysed in this paper. In the first case, the filling of the ash in the cooler has been analysed and in the second case, the phenomenon of fluidized bed bubbling in the ash cooler has been simulated. The study the of flow characteristics of hot ash has been studied. The contours of temperature, phase volume and bubbling have been analyzed in this paper.

  20. Physicochemical properties and heavy metals leachability of fly ash from coal-fired power plant

    Institute of Scientific and Technical Information of China (English)

    Xiang Wei; Han Baoping; Zhou Dong; Nzihou Ange

    2012-01-01

    The physicochemical properties of fly ash from two kinds of coal-fired power plants were studied.Three aspects were examined:the micro-morphology,the mineral composition and the content of heavy met als.The results show that the fly ash from plants using a circulating fluidized bed are more irregular particles,while the particles from the plants using a pulverized coal-fired boiler are mainly spherical in shape.Quartz and mullite are the main crystalline phases in the ash.Clearly,both the technology and the coal used by a power plant can influence the mineral composition of the ash.The mineral composition of fly ash from a circulating fluidized bed is more complex than that from a pulverized coal-fired boiler.The quantity of elements found in the fly ash is greater than that found in the bottom ash for the same plant.Heavy metals are likely to be enriched in the fly ash.Heavy metal leachability was studied using two leaching methods.The results indicate that most of the heavy metals that leached during either batch leaching or column leaching experiments did not exceed the related maximum concentration standards.But Ni concentrations in the leachates from both batch and column tests exceed the standard.The highest excess rates in both tests were 572% and 497%,which levels might threaten the environment.

  1. Liners for waste containment constructed with class F and C fly ashes.

    Science.gov (United States)

    Palmer, B G; Edil, T B; Benson, C H

    2000-09-15

    Hydraulic conductivity of a Class F fly ash containing residual organic carbon was evaluated in this study using laboratory and field tests. Compacted specimens of the Class F fly ash mixed with various materials (sand, Class C fly ash, and bottom ash) were prepared in the laboratory at various water contents and different compactive efforts. Hydraulic conductivity of the compacted specimens was measured using flexible-wall permeameters. A test pad was constructed to determine whether a low hydraulic conductivity liner could be constructed with Class F fly ash mixtures. Sealed double-ring infiltrometers and two-stage borehole permeameters were used to measure the field hydraulic conductivity of the test pad. Specimens were also removed from the test pad for hydraulic conductivity testing in the laboratory. Results of the study showed that mixtures of Class F and Class C fly ashes along with coarse aggregate can be compacted to hydraulic conductivities needed for landfill liners provided compaction is wet of optimum water content. The field tests showed that constructing a fly ash liner with hydraulic conductivities similar to those found in the laboratory is challenging, and requires careful attention to factors that result in cracks and permeable interlift regions that result in high field hydraulic conductivity. Leachate collected from the base of the test pad also showed that metal leaching must be considered when designing a liner with fly ash.

  2. Levels of polycyclic aromatic hydrocarbons in different types of hospital waste incinerator ashes.

    Science.gov (United States)

    Zhao, Lijuan; Zhang, Fu-Shen; Hao, Zhengping; Wang, Hailin

    2008-07-01

    Waste ashes from three types of hospital waste (HW) incinerators, built in SARS (Severe Acute Respiratory Syndrome) period and currently running in China, were collected and polycyclic aromatic hydrocarbons (PAH) properties in the ashes were investigated. The mean summation PAH levels in the waste ashes varied widely from 4.16 mg kg(-1) to 198.92 mg kg(-1), and the mean amounts of carcinogenic PAHs ranged from 0.74 to 96.77 mg kg(-1), exceeding the limits regulated by several countries. Among the three types of incinerators, two medium-scale incinerators generated relatively high levels of PAHs (mean summation PAH 22.50 and 198.92 mg kg(-1)) compared to small-scale and large-scale incinerators (mean summation PAH 4.16 and 16.43 mg kg(-1)). Bottom ashes were dominated by low molecular weight PAHs (LM-PAH; containing two- to three-ringed PAHs) and medium molecular weight PAHs (MM-PAH; containing four-ringed PAHs), while fly ashes were abundant in MM-PAH and high molecular weight PAHs (HM-PAH, containing five- to six-ringed PAHs). Statistical analysis indicated that there was a positive relationship (R2=0.88) between organic matter and total PAHs thus it has the potential to be used as an indicator for PAHs in HW ashes. Moreover, it was found that PAHs in the ashes correlated highly with some metallic elements either positively (e.g. Fe, Ti, Mg) or negatively (Ca), indicating that these elements might promote or prevent PAH formation during HW combustion. Although bottom ash resulted from HW incinerators has not been classified as hazardous material, the results of this study indicated that this type of waste ash contained high levels of PAHs thus need special treatment before landfill.

  3. Financial Crisis

    Institute of Scientific and Technical Information of China (English)

    黄骅

    2012-01-01

      Financial crisis started from America and soon spread all over the world. How did this happen? What government has done to rescue the economy and what should we do to help? Is financial crisis inevitable? These questions have bothered me for a long time. However, if we use a macroeconomist eye to view the world, all the questions seemed clear and crystal.

  4. Leaching optimization of municipal solid waste incineration ash for resource recovery: A case study of Cu, Zn, Pb and Cd.

    Science.gov (United States)

    Tang, Jinfeng; Steenari, Britt-Marie

    2016-02-01

    Ash from municipal solid waste incineration (MSWI) may be quite cumbersome to handle. Some ash fractions contain organic pollutants, such as dioxins, as well as toxic metals. Additionally, some of the metals have a high value and are considered as critical to the industry. Recovery of copper, zinc and lead from MSWI ashes, for example, will not only provide valuable metals that would otherwise be landfilled but also give an ash residue with lower concentrations of toxic metals. In this work, fly ash and bottom ash from an MSWI facility was used for the study and optimization of metal leaching using different solutions (nitric acid, hydrochloric acid and sulfuric acid) and parameters (temperature, controlled pH value, leaching time, and liquid/solid ratio). It was found that hydrochloric acid is relatively efficient in solubilizing copper (68.2±6.3%) and zinc (80.8±5.3%) from the fly ash in less than 24h at 20°C. Efficient leaching of cadmium and lead (over 92% and 90% respectively) was also achieved. Bottom ash from the same combustion unit was also characterized and leached using acid. The metal yields were moderate and the leachates had a tendency to form a gelatinous precipitate, which indicates that the solutions were actually over-saturated with respect to some components. This gel formation will cause problems for further metal purification processes, e.g. solvent extraction.

  5. Characteristics of Coal Ashes in Yanzhou Mining District and Distribution of Trace Elements in Them

    Institute of Scientific and Technical Information of China (English)

    刘桂建; 彭子成; 杨萍玥; 桂和荣; 王桂梁

    2001-01-01

    In the process of combustion of coal organic and inorganic materials in it will undergo a complex variation. Part of them will become volatiles and, together with coal smoke, enter into atmosphere, some will remain in micro-particulates such as ash and dust and find their way into atmosphere in the form of solid particles, and the rest will be retained in ash and slag. Coal ashes are the residues of organic and inorganic substances in coal left after coal combustion and the composition of coal ashes is dependent on that of minerals and organic matter in coal This paper deals with the chemical composition of coal ashes, the distribution of trace elements in them and their petrological characteristics, and also studies the relationship between the yield of coal ashes and the distribution of trace elements. In addition, a preliminary study is also under taken on the factors that affect the chemical composition of coal ashes. As viewed from the analyses of coal ash samples collected from the Yanzhou mining district, it can be seen clearly that coal ashes from the region studied are composed chiefly of crystalline materials, glassy ma terials and uncombusted organic matter and the major chemical compositions are SiO2, A12O3,Fe2O3, and CaO, as well as minor amounts of SO3, P2O5, Na2O, K2O and TiO2. During the combustion of coal, its trace elements will be redistributed and most of them are enriched in coal ashes. At the same time, the concentrations of the trace elements in flying ash are much higher than those of bottom ash, i.e. , with decreasing particle-size of coal ashes their concen trations will become higher and higher. So the contents of trace elements are negatively propor tional to the particle-size of coal ashes. There has been found a positive correlation between the trace elements Th, V, Zn, Cu and Pb and the yield of coal ashes while a negative correlation between C1 and the yield of coal ashes.

  6. Ash Aggregates in Proximal Settings

    Science.gov (United States)

    Porritt, L. A.; Russell, K.

    2012-12-01

    Ash aggregates are thought to have formed within and been deposited by the eruption column and plume and dilute density currents and their associated ash clouds. Moist, turbulent ash clouds are considered critical to ash aggregate formation by facilitating both collision and adhesion of particles. Consequently, they are most commonly found in distal deposits. Proximal deposits containing ash aggregates are less commonly observed but do occur. Here we describe two occurrences of vent proximal ash aggregate-rich deposits; the first within a kimberlite pipe where coated ash pellets and accretionary lapilli are found within the intra-vent sequence; and the second in a glaciovolcanic setting where cored pellets (armoured lapilli) occur within Diamond Mine, Canada, are the residual deposits within the conduit and vent of the volcano and are characterised by an abundance of ash aggregates. Coated ash pellets are dominant but are followed in abundance by ash pellets, accretionary lapilli and rare cored pellets. The coated ash pellets typically range from 1 - 5 mm in diameter and have core to rim ratios of approximately 10:1. The formation and preservation of these aggregates elucidates the style and nature of the explosive phase of kimberlite eruption at A418 (and other pipes?). First, these pyroclasts dictate the intensity of the kimberlite eruption; it must be energetic enough to cause intense fragmentation of the kimberlite to produce a substantial volume of very fine ash (sustained plume attended by concomitant production of pyroclastic density currents. The size and internal structure of the armoured lapilli provide constraints on the nature of the initial explosive phase of eruption at Kima'Kho. Their proximity to the vent also indicates rapid aggregation within the eruption plume. Within both sequences rapid aggregation of ash particles occurred in proximity to the vent. However, the conditions were substantially different leading to the production of armoured

  7. Dielectric properties of fly ash

    Indian Academy of Sciences (India)

    S C Raghavendra; R L Raibagkar; A B Kulkarni

    2002-02-01

    This paper reports the dielectric properties of fly ash. The dielectric measurements were performed as a function of frequency and temperature. The sample of fly ash shows almost similar behaviour in the frequency and temperature range studied. The large value of dielectric constant in the typical frequency range is because of orientation polarization and tight binding force between the ions or atoms in the fly ash. The sample of fly ash is of great scientific and technological interest because of its high value of dielectric constant (104).

  8. Effects of Characteristics of Fly Ash on the Properties of Geopolymer

    Institute of Scientific and Technical Information of China (English)

    杜海燕; 杨立娜; 高婉琪; 刘家臣

    2016-01-01

    The properties of two types of fly ash geopolymers made from class F fly ashes produced in wet bottom and dry bottom boilers were investigated in the present study. The source material used in the geopolymer concrete was activated with sodium hydroxide and sodium silicate solution. The results revealed that the geopolymer pro-duced with wet bottom boiler fly ash(CZ-FA)hardened quickly, and had higher early-age strength and lower shrinkage than the geopolymer produced with dry bottom boiler fly ash(SX-FA). The compressive strength of the two geopolymers made from CZ-FA and SX-FA was 45 MPa and 15 MPa respectively when cured at 60℃ and delayed for 14 d. However, after 90 days’ delay, the compressive strength of both the samples is almost the same, up to 80 MPa. Nearly 20% volume shrinkage of the samples made from SX-FA was much higher than that made from CZ-FA, which was almost zero. XRD, SEM/EDS and FT-IR were used to analyze the main reason of the dif-ferences.

  9. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles

    Directory of Open Access Journals (Sweden)

    A. Kylling

    2013-10-01

    Full Text Available The reverse absorption technique is often used to detect volcanic clouds from thermal infrared satellite measurements. From these measurements particle size and mass loading may also be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculate thermal infrared optical properties of highly irregular and porous ash particles and compare these with mass- and volume-equivalent spherical models. Furthermore, brightness temperatures pertinent to satellite observing geometry are calculated for the different ash particle shapes. Non-spherical shapes and volume-equivalent spheres are found to produce a detectable ash signal for larger particle sizes than mass-equivalent spheres. The assumption of mass-equivalent spheres for ash mass loading estimates will underestimate the mass loading by several tens of percent compared to morphologically complex inhomogeneous ash particles.

  10. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles

    Science.gov (United States)

    Kylling, A.; Kahnert, M.; Lindqvist, H.; Nousiainen, T.

    2013-10-01

    The reverse absorption technique is often used to detect volcanic clouds from thermal infrared satellite measurements. From these measurements particle size and mass loading may also be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculate thermal infrared optical properties of highly irregular and porous ash particles and compare these with mass- and volume-equivalent spherical models. Furthermore, brightness temperatures pertinent to satellite observing geometry are calculated for the different ash particle shapes. Non-spherical shapes and volume-equivalent spheres are found to produce a detectable ash signal for larger particle sizes than mass-equivalent spheres. The assumption of mass-equivalent spheres for ash mass loading estimates will underestimate the mass loading by several tens of percent compared to morphologically complex inhomogeneous ash particles.

  11. Ashes from oily sewage sludge combustion: chemistry, mineralogy and leaching properties

    Directory of Open Access Journals (Sweden)

    Róbert Polc

    2016-07-01

    Full Text Available In the current paper the chemical and mineralogical properties of bottom ash and fly ash from oily sewage sludge combustion are investigated. The mineralogical composition and the morphology of ashes were determined by X-ray powder diffraction (XRD in combination with scanning electron microscopy with quantitative energy-dispersive X-ray microanalysis (SEM-EDX. In addition, a leaching test results are presented to shed light on the potential toxicity of studied materials and their impact on the environment is discussed. Both of the studied materials are final products of thermal oxidation at industrial sludge incinerator. This facility aims to sanitary disposal of mechanical and biological sludge from industrial wastewater treatment plant. Bottom ash and fly ash are relatively stable solid products with slightly different chemical and mineralogical composition that reflects their different origin – burning condition in furnace vs. flues gas cleaning technology. Leaching tests of both mentioned materials were implemented under laboratory conditions. The aim of the laboratory tests was to determine the possibility of the pollutants release into the environment. The data presented herein support the importance of detailed mineralogical and geochemical study for the better understanding of the leaching tests. The obtained results showed that both of the sewage sludge ash samples exceed the criteria for accepting waste in landfilles established for Slovakia.

  12. Study of thermal-flow processes in ash cooler cooperating with CFB boiler

    Directory of Open Access Journals (Sweden)

    Paweł Regucki

    2016-03-01

    Full Text Available The article presents an example of thermal-flow analysis of the bottom ash cooler cooperating with the circulating fluidized bed boiler. There is presented a mathematical model of series-parallel hydraulic system supplying the ash cooler in cooling water. The numerical calculations indicate an influence of changes of the pipeline geometrical parameters on the cooling water flow rate in the system. Paper discusses the methodology of the studies and presents examples of the results of thermal balance calculations based on the results of measurements. The numerical results of the thermal-flow analysis in comparison with the measurements on the object indicate that the presented approach could be used as a diagnostic tool investigating the technical state of the bottom ash cooler.

  13. Ash after forest fires. Effects on soil hydrology and erosion

    Science.gov (United States)

    Bodí, Merche B.

    2013-04-01

    from certain Eucaliptus and Pinus), or if clog soil pores (depending also on the soil type). If ash is wettable, it can store even 80% of its volume and then it will delay and reduce overland flow proportionally to the thickness of the ash layer. Once ash gets saturated, the flow tends to adjust to an infiltration rate similar to the soil itself, or sometimes higher due to the protection of ash that can reduce soil water repellency and soil sealing (Bodí et al. 2011, 2012). Still, many other aspects on ash remain unknown and ash present us more questions like, what it is its role on the carbon cycle? what is the extent of the ahs effects at basin scale? what is the fate of ash and how long it remains in the ecosystem? are there specific effects of ash depending on the ecosystem and so the type of ash? Acknowledgements This work was supported financially by a research fellowship (AP2007-04602) from the Spanish Ministry of Science and Innovation (M.B. Bodí) and the projects PT2009-0073 and CGL2010-21670-C02-01. References Bodí, M.B., Mataix-Solera, J., Doerr, S.H., Cerdà, A., 2011, The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type, burn severity and total organic carbon content. Geoderma 160, 599-607. Bodí, M.B., Doerr, S.H., Cerdà, A., Mataix-Solera, J., 2012, Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma 191, 14-23 Cerdà, A., 1998, Changes in overland flow and infiltration after a rangeland fire in a Mediterranean scrubland. Hydrological Processes 12, 1031-1042. Cerdà, A., Doerr, S.H., 2008, The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena 74, 256-263. Woods, S.W., Balfour, V., 2008, The effect of ash on runoff and erosion after a forest wildfire, Montana, U.S.A. International Journal of Wildland Fire 17, 535-548.

  14. 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.

  15. Investigations of ash fouling with cattle wastes as reburn fuel in a small-scale boiler burner under transient conditions.

    Science.gov (United States)

    Oh, Hyukjin; Annamalai, Kalyan; Sweeten, John M

    2008-04-01

    Fouling behavior under reburn conditions was investigated with cattle wastes (termed as feedlot biomass [FB]) and coal as reburn fuels under a transient condition and short-time operation. A small-scale (30 kW or 100,000 Btu/hr) boiler burner research facility was used for the reburn experiments. The fuels considered for these experiments were natural gas (NG) for the ashless case, pure coal, pure FB, and blends of coal and FB. Two parameters that were used to characterize the ash "fouling" were (1) the overall heat-transfer coefficient (OHTC) when burning NG and solid fuels as reburn fuels, and (2) the combustible loss through ash deposited on the surfaces of heat exchanger tubes and the bottom ash in the ash port. A new methodology is presented for determining ash-fouling behavior under transient conditions. Results on the OHTCs for solid reburn fuels are compared with the OHTCs for NG. It was found that the growth of the layer of ash depositions over longer periods typically lowers OHTC, and the increased concentration of ash in gas phase promotes radiation in high-temperature zones during initial periods while decreasing the heat transfer in low-temperature zones. The ash analyses indicated that the bottom ash in the ash port contained a smaller percentage of combustibles with a higher FB percentage in the fuels, indicating better performance compared with coal because small particles in FB burn faster and the FB has higher volatile matter on a dry ash-free basis promoting more burn out.

  16. HIS 103 ASH course tutorial/tutorialoutlet

    OpenAIRE

    NARESH 1

    2015-01-01

    For more course tutorials visit www.tutorialoutlet.com   HIS 103 Week 1 DQ 1 (Transition to Agriculture) (Ash) HIS 103 Week 1 DQ 2 (Early Complex Societies) (Ash) HIS 103 Week 1 Quiz (Ash) HIS 103 Week 1 Assignment (Ash) HIS 103 Week 2 Assignment Greco Roman Influence Paper (Ash) HIS 103 Week 2 DQ 1 Chinese Social and Political Order Systems (Ash) HIS 103 Week 2 DQ 2 Caste System (Ash) HIS 103 Week 2 Quiz (Ash) HIS 103 Week 3 Assignment Black Death Dra...

  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. 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...

  19. FINANCIAL LITERACY, FINANCIAL EDUCATION AND ECONOMIC OUTCOMES

    OpenAIRE

    Hastings, Justine S.; Brigitte C. Madrian; Skimmyhorn, William L.

    2013-01-01

    In this article we review the literature on financial literacy, financial education, and consumer financial outcomes. We consider how financial literacy is measured in the current literature, and examine how well the existing literature addresses whether financial education improves financial literacy or personal financial outcomes. We discuss the extent to which a competitive market provides incentives for firms to educate consumers or offer products that facilitate informed choice. We revie...

  20. Optoelectronic system of online measurements of unburned carbon in coal fly ash

    Science.gov (United States)

    Golas, Janusz; Jankowski, Henryk; Niewczas, Bogdan; Piechna, Janusz; Skiba, Antoni; Szkutnik, Wojciech; Szkutnik, Zdzislaw P.; Wartak, Ryszarda; Worek, Cezary

    2001-08-01

    Carbon-in-ash level is an important consideration for combustion efficiency as well as ash marketing. The optoelectronic analyzing system for on-line determination and monitoring of the u burned carbon content of ash samples is presented. The apparatus operates on the principle that carbon content is proportional to the reflectance of IR light. Ash samples are collected iso kinetically from the flue gas duct and placed in a sample tube with a flat glass bottom. The same is then exposed to a light. The reflectance intensity is used by the system's computer to determine residual carbon content from correlation curves. The sample is then air purged back to the duct or to the attached sample canister to enable laboratory check analysis. The total cycle time takes between 5 and 10 minutes. Real time result of carbon content with accuracy 0.3-0.7 percent are reported and can be used for boiler controlling.

  1. Post-Chernobyl 137Cs in the atmosphere of Thessaloniki: a consequence of the financial crisis in Greece.

    Science.gov (United States)

    Stoulos, S; Ioannidou, A; Vagena, E; Koseoglou, P; Manolopoulou, M

    2014-02-01

    The background radiation level of (137)Cs at the urban atmosphere of Thessaloniki has been increased during the recent decade only due to the Fukushima accident fallout. Since then, no other signal of (137)Cs was observed until the winter period of 2013, when slightly elevated (137)Cs concentrations were measured. The (137)Cs signals observed were up to 12 μBq m(-3), mainly during holidays and weekends followed by lower or even non-detectable activities in the next working days. Those episodes are attributed to the increase of biomass products combustion for residential heating as this year the tax of oil for heating was drastically raised as a consequence of the financial crisis. A preliminary survey of various wood products as well as of bottom ashes from different domestic burning devices is presented. (137)Cs concentrations up to 11 Bq kg(-1) were measured in wood products and up to 500 Bq kg(-1) in ash samples.

  2. Knowledge Transfer from the Forestry Sector to the Agricultural Sector concerning Ash Recycling; Kunskapsoeverfoering fraan skogssektorn till jordbrukssektorn angaaende askaaterfoering

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Johanna; Salomon, Eva

    2009-02-15

    Cultivation of energy crops on arable land is increasing in Sweden. More than half these crops can be used for combustion, increasing the amount of ash that can be recycled to arable land. Ash is an interesting agricultural fertiliser, but more knowledge is needed before it can be applied and handled in a controlled way. Knowledge and experience concerning recycling of ash within the forest sector can be transferred to the agricultural sector. This project examined ways for ash producers to ensure safe long-term disposal of ash and to improve plant nutrient recycling. The overall aims were to identify experiences and knowledge within forestry that could be applied in agriculture; to identify gaps in knowledge and research requirements regarding ash recycling to arable land; and to produce recommendations on how to increase ash recycling. Literature describing the conditions for ash application to arable land and existing knowledge about ash recycling to forestry were reviewed. Nutrient balances were drawn up for phosphorus, cadmium, zinc and copper, which are relevant in biofuel ash recycling to agriculture. Data on ash application, mainly on forest land, were collected through telephone interviews. For ash to be more attractive for farmers, the ash product must be a realistic alternative to artificial fertilisers. Research and demonstration projects are needed to study the effects of ash on yield and quality in different crops. Different biofuel ash products have differing qualities and can thus have different fields of application within agriculture and can be applied in varying amounts. For example, clean straw ash has a low P and Cd content and mainly supplies potassium and lime. The balance calculations showed that the highest quality ash for arable land is bottom ash from grate combustion of forest trash with 2-5 % of willow. There are both differences and similarities between ash application in agriculture and forestry. An important feature is the

  3. Characteristics variation of coal combustion residues in an Indian ash pond.

    Science.gov (United States)

    Asokan, Pappu; Saxena, Mohini; Aparna, Asokan; Asolekar, Shyam R; Asoletar, Shyam R

    2004-08-01

    Coal-fired power plants all over the world are cited as one of the major sources that generate huge quantities of coal combustion residues (CCRs) as solid wastes. Most frequently CCRs are collected through electrostatic precipitators, mixed with bottom ash by hydraulic systems and deposited in ash ponds. The quality of the CCRs at different locations in one of the ash ponds in Central India was evaluated to understand the variation in characteristics with a view to effective utilization. Results revealed that the presence of fine particles (distance from the ash slurry inlet zone in the ash pond. Wide variations in the bulk density (800-980 kg m(-3)), porosity (45-57%) and water-holding capacity (57.5-75.7%) of CCRs were recorded. With increasing distance the pH of the CCRs decreased (from 9.0 to 8.2) and electrical conductivity increased (from 0.25 to 0.65 dS m(-3)). The presence of almost all the heavy metals in CCRs exhibited an increase with distance from the ash slurry discharge zone due to the increase in surface area (from 0.1038 to 2.3076 m2 g(-1)) of CCRs particles. The present paper describes the variation of characteristics of CCRs deposited in the ash pond and their potential applications.

  4. Application of Bokashi Botom Ash for Increasing Upland Rice Yield and Decreasing Grain Pb Content in Vitric Hapludans

    Directory of Open Access Journals (Sweden)

    Nunung Sondari

    2012-05-01

    Full Text Available Greenhouse experiment was conducted at Agricultural Faculty of Winaya Mukti University Tanjungsari SumedangRegency, from May to October 2009. The objective of this experiment was to study the effect of bokashi bottom ashon the growth, yield, and Pb content of upland rice. The experiment used a Randomized completely Block Design(RBD which consisted of five treatments and five replications. The treatments were level of bokashi bottom ash i.e.0, 5, 10, 15, and 20 Mg ha-1. The results showed that the application of bokashi bottom ash increased the growth andyield of upland rice of Situbagendit variety except plant height at age of 21 days after seedling (DAS. Application15 Mg ha -1 of bokashi bottom ash gave the best effect to the plant height, number of leaves, number of tillers andshoot/root ratio, while applications of 10, 15 and 20 Mg ha -1 increased number of productive tillers, amount of filledgrains, and weight of grains. Bokashi bottom ash did not affect the heavy metal content of upland rice grain ofSitubagendit variety.

  5. 49 CFR 230.69 - Ash pans.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Ash pans. 230.69 Section 230.69 Transportation... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Ash Pans § 230.69 Ash pans. Ash pans shall be securely supported from mud-rings or frames with no part less than...

  6. Additives for granulating and removing ash from finely dispersed coal

    Energy Technology Data Exchange (ETDEWEB)

    Ivabutin, K.; Fukuda, T.; Goto, M.; Miva, K.; Murata, T.; Taguti, D.

    1982-07-31

    One to thirty percent of a 0.01 to 10 percent solution of synthetic polymers (SPL) of ethylene and vinylacetate or methacrylate, polybutadiene rubbers, resins based on vinylchloride, low molecular PA and so on in an organic solvent mixed with high boiling point bottoms of coal distillation or that of crude oil and or an inorganic electrolyte (a sulfate or phosphate of an alkaline metal) is added to an aqueous suspension of coal powder in order to utilize the dust particles of the coal and to make low ash granules from them.

  7. 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.

  8. Financial Inclusion, Financial Regulation, and Financial Education in Thailand

    OpenAIRE

    Tambunlertchai, Kanittha

    2015-01-01

    This paper addresses the issue of financial inclusion in Thailand through the lens of an institutional analysis, which takes into consideration the desired outcomes, the service providers and enabling agencies, and the regulatory context that shape the existing provision of financial inclusion in Thailand. In discussing the achievement of the desired outcomes in terms of financial inclusion, the issues of financial education and financial regulation, which provide the contexts within which th...

  9. AshMeadowsNaucorid_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Naucorid (Ambrysus amargosus) occur. "Nevada, Nye County. Point of Rocks Springs and...

  10. AshMeadowsNaucorid_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Naucorid (Ambrysus amargosus) occur. "Nevada, Nye County. Point of Rocks Springs and...

  11. 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.)

  12. 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.)

  13. Financial Statements Analysis

    OpenAIRE

    Tănase Alin-Eliodor

    2014-01-01

    This article focuses on analyzing of a consolidated financial statements of a hypothetically SME. The interpretation of the financial position and performances is based on the more than 40 financial key ratios computed by using financial data from consolidated income statement, consolidated financial position and cash flow. However additional data from notes to financial statements are provided.

  14. Financial Statements Analysis

    Directory of Open Access Journals (Sweden)

    Tănase Alin-Eliodor

    2014-10-01

    Full Text Available This article focuses on analyzing of a consolidated financial statements of a hypothetically SME. The interpretation of the financial position and performances is based on the more than 40 financial key ratios computed by using financial data from consolidated income statement, consolidated financial position and cash flow. However additional data from notes to financial statements are provided.

  15. Improving volcanic ash predictions with the HYSPLIT dispersion model by assimilating MODIS satellite retrievals

    Science.gov (United States)

    Chai, Tianfeng; Crawford, Alice; Stunder, Barbara; Pavolonis, Michael J.; Draxler, Roland; Stein, Ariel

    2017-02-01

    Currently, the National Oceanic and Atmospheric Administration (NOAA) National Weather Service (NWS) runs the HYSPLIT dispersion model with a unit mass release rate to predict the transport and dispersion of volcanic ash. The model predictions provide information for the Volcanic Ash Advisory Centers (VAAC) to issue advisories to meteorological watch offices, area control centers, flight information centers, and others. This research aims to provide quantitative forecasts of ash distributions generated by objectively and optimally estimating the volcanic ash source strengths, vertical distribution, and temporal variations using an observation-modeling inversion technique. In this top-down approach, a cost functional is defined to quantify the differences between the model predictions and the satellite measurements of column-integrated ash concentrations weighted by the model and observation uncertainties. Minimizing this cost functional by adjusting the sources provides the volcanic ash emission estimates. As an example, MODIS (Moderate Resolution Imaging Spectroradiometer) satellite retrievals of the 2008 Kasatochi volcanic ash clouds are used to test the HYSPLIT volcanic ash inverse system. Because the satellite retrievals include the ash cloud top height but not the bottom height, there are different model diagnostic choices for comparing the model results with the observed mass loadings. Three options are presented and tested. Although the emission estimates vary significantly with different options, the subsequent model predictions with the different release estimates all show decent skill when evaluated against the unassimilated satellite observations at later times. Among the three options, integrating over three model layers yields slightly better results than integrating from the surface up to the observed volcanic ash cloud top or using a single model layer. Inverse tests also show that including the ash-free region to constrain the model is not

  16. Pre-treatment and recirculation of wood ashes; Forbehandling og recirkulering af flisaske

    Energy Technology Data Exchange (ETDEWEB)

    Skov, S.; Ingerslev, M.

    2011-07-01

    Harvest of forest biomass for energy production may lead to a significant export of nutrients from the forest. Ash spreading and recycling of nutrients from wood chip combustion to the forest has come into focus as a means for counteracting the nutrient export. A study was carried out to examine the retention of various elements in the different ash fractions and utilize the nutrient recovery to evaluate the fertilizer quality of the examined ash. The mass and element flux of wood chips, bottom ash, cyclone fly ash and condensation sludge at Ebeltoft central heating plant was studied over a four-day period in spring 2005. Substantial amounts of nutrients were retained in the fly ash (P, Ca, Mg, Mn and Cu have a recovery higher than 60 % and K, S and Fe have a recovery higher than 30 %). The recovery of elements in the bottom ash was smaller. The added recovery of the usable fractions of ashes (both fly ash and bottom ash) exceeded 75 % for the nutrients P, Ca, Mn and Mg. Both these ash fractions should be considered for fertilization. To examine how ash application affects the forest and Christmas tree stand ecosystem and especially the element budget field experiments were established and monitored intensively. Wood ash is alkaline and by spreading ash in the forest ecosystem, the chemistry of soil water and soil is affected. This introduces a risk of scorching the organisms, eg. mosses but also of root damaging and thereby an impaired water and nutrient uptake as a result. The ash contains salts. Some of these salts, especially metal chlorides and metal sulfates can be dissolved quickly and causes a pH decrease in soil water. There may be a risk that the geochemical conditions in the soil changed dramatically within a relatively short period. These changes can affect nutrient concentrations in soil water and mineralization of organic matter in soil. This increases the risk of leaching and permanent loss of nutrients. These adverse effects of wood ash application

  17. ITER helium ash accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, J.T.; Hillis, D.L.; Galambos, J.; Uckan, N.A. (Oak Ridge National Lab., TN (USA)); Dippel, K.H.; Finken, K.H. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Plasmaphysik); Hulse, R.A.; Budny, R.V. (Princeton Univ., NJ (USA). Plasma Physics Lab.)

    1990-01-01

    Many studies have shown the importance of the ratio {upsilon}{sub He}/{upsilon}{sub E} in determining the level of He ash accumulation in future reactor systems. Results of the first tokamak He removal experiments have been analysed, and a first estimate of the ratio {upsilon}{sub He}/{upsilon}{sub E} to be expected for future reactor systems has been made. The experiments were carried out for neutral beam heated plasmas in the TEXTOR tokamak, at KFA/Julich. Helium was injected both as a short puff and continuously, and subsequently extracted with the Advanced Limiter Test-II pump limiter. The rate at which the He density decays has been determined with absolutely calibrated charge exchange spectroscopy, and compared with theoretical models, using the Multiple Impurity Species Transport (MIST) code. An analysis of energy confinement has been made with PPPL TRANSP code, to distinguish beam from thermal confinement, especially for low density cases. The ALT-II pump limiter system is found to exhaust the He with maximum exhaust efficiency (8 pumps) of {approximately}8%. We find 1<{upsilon}{sub He}/{upsilon}{sub E}<3.3 for the database of cases analysed to date. Analysis with the ITER TETRA systems code shows that these values would be adequate to achieve the required He concentration with the present ITER divertor He extraction system.

  18. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles

    OpenAIRE

    A. Kylling; Kahnert, M.; Lindqvist, H.; T. Nousiainen

    2013-01-01

    The reverse absorption technique is often used to detect volcanic clouds from thermal infrared satellite measurements. From these measurements particle size and mass loading may also be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculate thermal infrared optical properties of highly irregular and porous ash particles and compare these with mass- and volume-equivalent spherical models. Furtherm...

  19. FINANCIAL LEASING

    OpenAIRE

    2014-01-01

    This essay deals with the several financial resources an enterprise counts on to purchase assets of the kind real state or chattels. A resource that does not risk solvency is the lease, through the retro-leasing variant that allows to obtain working capital by selling one of its fixed assets without giving its use up. El ensayo, trata sobre las fuentes de fondeo que tiene la empresa para adquirir un activo mueble o inmueble son diversas, una de ellas que no compromete la liquidez es el con...

  20. Dewatering of ashes from mixed fuels. Experiences and results from Tekniska Verken in Linkoeping; Avvattning av aska fraan blandbraenslen. Erfarenheter och resultat fraan Tekniska Verken i Linkoeping

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Ulf; Fredriksson, Anders; Lindahl, Inge [Tekniska Verken i Linkoeping AB (Sweden); Arevius, Anna; Sjoeblom, Rolf [AaF-Energikonsult AB, Stockholm (Sweden)

    2003-12-01

    Unit 3 at Tekniska Verken i Linkoeping (TVL) has a grid type furnace. During the firing season 2000 - 2001, the fuel has been comprising 45 % recovered wood chip, 45 % bark and 10 % recovered plastic material. The outfeed has been wet, and flyash and bottom ash have been mixed in the process. During 1999, about 19,000 tonnes of ash with a water content of about 50 % have been generated. The procedure has implied drawbacks in the form of handling of sludge and disposal of material with a high water content. The purpose of the work carried out has been to provide a basis for design of a handling in which these drawbacks have been eliminated, and which supports other destinations for the bottom ash than disposal. The search for information showed that a number of reactions, in particular hydratisation and recrystallisation, take place when ash is in contact with water. The process is strongly dependent on the chemical composition of the ash. The result is influenced not only by the chemical reactions that occur but also by the order in which they take place. Fly ash is very reactive while bottom ash is relatively inert. The experiments in the laboratory scale showed that bottom ash drained well while fly ash as well as different mixtures of fly ash and bottom ash are relatively impermeable to water. The ageing experiments which were carried out did not indicate any particular alteration in the permeability. Tests on a reduced scale clearly showed that bottom ash drains rapidly without the aid of vacuum and that the field capacity (the relative amount of water which does not drain) is low. Mixtures of bottom ash and fly ash drained more when vacuum was applied. However, such mixtures cured within a few hours and this lead to a substantial decrease in permeability. Tests on a pilot scale were conducted using three different methods of dewatering. The tests on self-percolation showed that most of the drainage water appeared during the first few hours where after the

  1. Pre-treatment and recirculation of wood ashes; Forbehandling og recirkulering af flisaske

    Energy Technology Data Exchange (ETDEWEB)

    Skov, S.; Ingerslev, M.

    2011-07-01

    Harvest of forest biomass for energy production may lead to a significant export of nutrients from the forest. Ash spreading and recycling of nutrients from wood chip combustion to the forest has come into focus as a means for counteracting the nutrient export. A study was carried out to examine the retention of various elements in the different ash fractions and utilize the nutrient recovery to evaluate the fertilizer quality of the examined ash. The mass and element flux of wood chips, bottom ash, cyclone fly ash and condensation sludge at Ebeltoft central heating plant was studied over a four-day period in spring 2005. Substantial amounts of nutrients were retained in the fly ash (P, Ca, Mg, Mn and Cu have a recovery higher than 60 % and K, S and Fe have a recovery higher than 30 %). The recovery of elements in the bottom ash was smaller. The added recovery of the usable fractions of ashes (both fly ash and bottom ash) exceeded 75 % for the nutrients P, Ca, Mn and Mg. Both these ash fractions should be considered for fertilization. To examine how ash application affects the forest and Christmas tree stand ecosystem and especially the element budget field experiments were established and monitored intensively. Wood ash is alkaline and by spreading ash in the forest ecosystem, the chemistry of soil water and soil is affected. This introduces a risk of scorching the organisms, eg. mosses but also of root damaging and thereby an impaired water and nutrient uptake as a result. The ash contains salts. Some of these salts, especially metal chlorides and metal sulfates can be dissolved quickly and causes a pH decrease in soil water. There may be a risk that the geochemical conditions in the soil changed dramatically within a relatively short period. These changes can affect nutrient concentrations in soil water and mineralization of organic matter in soil. This increases the risk of leaching and permanent loss of nutrients. These adverse effects of wood ash application

  2. Assessing the environmental impact of ashes used in a landfill cover construction.

    Science.gov (United States)

    Travar, I; Lidelöw, S; Andreas, L; Tham, G; Lagerkvist, A

    2009-04-01

    Large amounts of construction materials will be needed in Europe in anticipation for capping landfills that will be closed due to the tightening up of landfill legislation. This study was conducted to assess the potential environmental impacts of using refuse derived fuel (RDF) and municipal solid waste incineration (MSWI) ashes as substitutes for natural materials in landfill cover designs. The leaching of substances from a full-scale landfill cover test area built with different fly and bottom ashes was evaluated based on laboratory tests and field monitoring. The water that drained off above the liner (drainage) and the water that percolated through the liner into the landfill (leachate) were contaminated with Cl(-), nitrogen and several trace elements (e.g., As, Cu, Mo, Ni and Se). The drainage from layers containing ash will probably require pre-treatment before discharge. The leachate quality from the ash cover is expected to have a minor influence on overall landfill leachate quality because the amounts generated from the ash covers were low, construction, which could contribute to the retention of trace elements in the liner in the long term. Hence, from an environmental view point, the placement of ashes in layers above the liner is more critical than within the liner.

  3. Solidification/stabilization of ash from medical waste incineration into geopolymers.

    Science.gov (United States)

    Tzanakos, Konstantinos; Mimilidou, Aliki; Anastasiadou, Kalliopi; Stratakis, Antonis; Gidarakos, Evangelos

    2014-10-01

    In the present work, bottom and fly ash, generated from incinerated medical waste, was used as a raw material for the production of geopolymers. The stabilization (S/S) process studied in this paper has been evaluated by means of the leaching and mechanical properties of the S/S solids obtained. Hospital waste ash, sodium hydroxide, sodium silicate solution and metakaolin were mixed. Geopolymers were cured at 50°C for 24h. After a certain aging time of 7 and 28 days, the strength of the geopolymer specimens, the leachability of heavy metals and the mineralogical phase of the produced geopolymers were studied. The effects of the additions of fly ash and calcium compounds were also investigated. The results showed that hospital waste ash can be utilized as source material for the production of geopolymers. The addition of fly ash and calcium compounds considerably improves the strength of the geopolymer specimens (2-8 MPa). Finally, the solidified matrices indicated that geopolymerization process is able to reduce the amount of the heavy metals found in the leachate of the hospital waste ash.

  4. Controlling formaldehyde emissions with boiler ash.

    Science.gov (United States)

    Cowan, Jennifer; Abu-Daabes, Malyuba; Banerjee, Sujit

    2005-07-01

    Fluidized wood ash reduces formaldehyde in air from about 20 to formaldehyde reduction increases with increasing moisture content of the ash. Sorption of formaldehyde to ash can be substantially accounted for by partitioning to the water contained in the ash followed by rate-controlling binding to the ash solids. Adsorption occurs at temperatures of up to 165 degrees C; oxidation predominates thereafter. It is proposed that formaldehyde could be stripped from an air stream in a fluidized bed containing ash, which could then be returned to a boiler to incinerate the formaldehyde.

  5. Evaluating the Effects of the Kingston Fly Ash Release on Fish Reproduction: Spring 2009 - 2010 Studies

    Energy Technology Data Exchange (ETDEWEB)

    Greeley Jr, Mark Stephen [ORNL; Adams, Marshall [ORNL; McCracken, Kitty [ORNL

    2012-05-01

    On December 22, 2008, a dike containing fly ash and bottom ash at the Tennessee Valley Authority's (TVA) Kingston Fossil Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits from the spill extended 4 miles upstream of the facility to Emory River mile 6 and downstream to Tennessee River mile 564 ({approx}8.5 miles downstream of the confluence of the Emory River with the Clinch River, and {approx}4 miles downstream of the confluence of the Clinch River with the Tennessee River). A byproduct of coal combustion, fly ash contains a variety of metals and other elements which, at sufficient concentrations and in specific forms, can be harmful to biological systems. The ecological effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to come from elevated levels of certain metals in the ash, particularly selenium, on fish reproduction and fish early life stages (Lemly 1993; Besser and others 1996). The ovaries of adult female fish in a lake contaminated by coal ash were reported to have an increased frequency of atretic oocytes (dead or damaged immature eggs) and reductions in the overall numbers of developing oocytes (Sorensen 1988) associated with elevated body burdens of selenium. Larval fish exposed to selenium through maternal transfer of contaminants to developing eggs in either contaminated bodies of water (Lemly 1999) or in experimental laboratory exposures (Woock and others 1987, Jezierska and others 2009) have significantly increased incidences of developmental abnormalities. Contact of fertilized eggs and developing embryos to ash in water and sediments may also pose an additional risk to the early life stages of exposed fish populations through direct uptake of metals and other ash constituents (Jezierska and others 2009). The establishment and maintenance of fish populations is intimately associated

  6. Culture from the Bottom Up

    Science.gov (United States)

    Atkinson, Dwight; Sohn, Jija

    2013-01-01

    The culture concept has been severely criticized for its top-down nature in TESOL, leading arguably to its falling out of favor in the field. But what of the fact that people do "live culturally" (Ingold, 1994)? This article describes a case study of culture from the bottom up--culture as understood and enacted by its individual users.…

  7. Culture from the Bottom Up

    Science.gov (United States)

    Atkinson, Dwight; Sohn, Jija

    2013-01-01

    The culture concept has been severely criticized for its top-down nature in TESOL, leading arguably to its falling out of favor in the field. But what of the fact that people do "live culturally" (Ingold, 1994)? This article describes a case study of culture from the bottom up--culture as understood and enacted by its individual users.…

  8. "Bottom-up" transparent electrodes.

    Science.gov (United States)

    Morag, Ahiud; Jelinek, Raz

    2016-11-15

    Transparent electrodes (TEs) have attracted significant scientific, technological, and commercial interest in recent years due to the broad and growing use of such devices in electro-optics, consumer products (touch-screens for example), solar cells, and others. Currently, almost all commercial TEs are fabricated through "top-down" approaches (primarily lithography-based techniques), with indium tin oxide (ITO) as the most common material employed. Several problems are encountered, however, in this field, including the cost and complexity of TE production using top-down technologies, the limited structural flexibility, high-cost of indium, and brittle nature and low transparency in the far-IR spectral region of ITO. Alternative routes based upon bottom-up processes, have recently emerged as viable alternatives for production of TEs. Bottom up technologies are based upon self-assembly of building blocks - atoms, molecules, or nanoparticles - generating thin patterned films that exhibit both electrical conductivity and optical transparency. In this Feature Article we discuss the recent progress in this active and exciting field, including bottom-up TE systems produced from carbon materials (carbon nanotubes, graphene, graphene-oxide), silver, gold, and other metals. The current hurdles encountered for broader use of bottom-up strategies along with their significant potential are analyzed.

  9. Building from the Bottom Up

    Science.gov (United States)

    2003-05-01

    through billions of years of prebiotic and molecular selection and evolution, there are bio-organic by Shuguang Zhang Building from the bottom up... Health , Du Pont-MIT Alliance, and the Whitaker Foundation. I also gratefully acknowledge Intel Corporation Academic Program for the generous donation

  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. Chemical characterization of ash generated from alfalfa stem gasification: Agricultural and environmental implications. Quarterly report, July 1, 1997--September 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, C.; Mozaffari, M.; Russelle, M.; Nater, E.

    1997-10-30

    This progress report provides results of Toxicity Characteristics Leaching Procedures (TCLP) and Synthetic Leachate Test Procedure (SLTP) for the alfalfa stem ash. The TCLP simulates solute leaching in landfill by using acetic acid as a solvent and SLTP simulates potential for leaching from synthetic acid rain. This report also provides information on detailed chemical characterization of organic and inorganic constituents of the ash. The analysis performed includes information on compounds that may represent a potential risk to human or animal health and those constituents that may have beneficial use as soil amendments and conditioners. A sample of the fly (filter) ash from the test burn conducted in Finland was received in May 1997 and used for initial investigation. Three additional fly ash samples and one sample of bottom ash (reactor bed ash) were received in June 1997. The samples were either tested at the University of Minnesota or sent to a reputable laboratory, and various tests were conducted according to the standard methods. The result of the comprehensive tests conducted in May 1997 (report submitted previously) were used as a screening procedure for conducting tests on June 1997 samples. To provide a more comprehensive representation of ash characteristics the results for fly ash received in May are presented along with results from fly ash samples received in July. The average, range and coefficient of variation (CV) are provided. The TCLP and SLTP tests conducted in the laboratory indicated that the concentration of heavy metals were below or close to the detection limits for fly and bottom ash samples (Tables 1 and 2). The ash was also characterized for a number of classes of organic compounds that may pose potential environmental or health risks. These are polyaromatic hydrocarbons (PAHs), total and individual dioxin and furan compounds.

  12. Accumulation of metals in vegetation established in ash constructions; Ackumulering av metaller i vegetation paa geotekniska askkonstruktioner

    Energy Technology Data Exchange (ETDEWEB)

    Hemstroem, Kristian; Wik, Ola (SGI, Statens geotekniska institut (Sweden)); Bramryd, Torleif; Johansson, Michael (Lunds Universitet, Miljoestrategi (Sweden)); Jaegerbrand, Annika (VTI, Statens Vaeg och transportforskningsinstitut (Sweden))

    2012-02-15

    The overall aim of this study was to investigate how the use of ash in a long-term perspective affects the surrounding flora and fauna with regard to the accumulation of metals in the ecosystem through plant uptake and exposure to grazing animals. The study included a field study and a cultivation experiment. In the field study, the accumulation of metals and metalloids in leaves of trees and shrubs that had self established and grown in lysimeters with aged MSWI bottom ash and aged biofuel ash was determined. In the cultivation experiment, the accumulation of metals and metalloids from the studied materials in ryegrass was determined. Reference materials in the cultivation experiment were two conventional geotechnical materials, crushed rock and excavated soil. Leaves from trees and bushes in the vicinity of the ash lysimeters were used as reference materials in the field study. Contamination of plant samples with particles, through splashing during rain, dusting, or in connection with sampling, proved to have had a major impact on the measured metal and metalloid concentrations in several grass samples in the cultivation experiment. The results also indicate that contamination of plant samples with particles occurred in the field study. In this case, probably due to atmospheric deposition. The particle contamination complicated the evaluation of some of the results in the project since the intention was to study accumulation by roots from the studied ash materials, but, on the other hand, the particle contamination showed the importance of taking into account the spreading of contaminants through particles as an exposure route for grazing animals. In the field study, only Cd and Zn in aspen, willow and birch exhibited elevated levels in the leaves due to root uptake from MSWI bottom ash compared to the reference samples. In addition, elevated levels of As was observed in leaves from trees in the biofuel ash. The total content of As was similar in all studied

  13. 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...

  14. Polychlorobenzenes and polychlorinated biphenyls in ash and soil from several industrial areas in North Vietnam: residue concentrations, profiles and risk assessment.

    Science.gov (United States)

    Nguyen, Thi Hue; Nguyen, Thi Thu Thuy; Nguyen, Hoang Tung

    2016-04-01

    Polychlorinated benzenes (PCBzs) including penta- and hexachlorobenzene can be unintentionally formed from thermal processes in different industrial activities, and very little information is available on the contamination and emission characteristics of these new persistent organic pollutants from industries in Vietnam. In this study, contamination of PCBzs (including penta- and hexachlorobenzene, named PeCBz and HCB, respectively) and PCBs (including CB-28, 52, 101, 153, 138, 180) in fly ash, bottom ash and soil from combustion processes of waste incineration, metallurgy (steel making and zinc production) and cement production from several provinces in the Northern Vietnam, including Hai Duong, Hanoi, Bac Ninh, Hai Phong and Thai Nguyen, was preliminary investigated. The PCBzs concentrations in fly ash, bottom ash and soil ranged from 2.7 to 100 ng g(-1), from 2.7 to 159 ng g(-1) and from 0.28 to 33.9 ng g(-1), respectively. Relatively high residues of PeCBz in fly ash and bottom ash from municipal waste incinerators in some provinces from the Northern Vietnam were encountered. Total PCBs concentrations ranged from 18.0 to 8260 ng g(-1), from 1.0 to 10600 ng g(-1) and from 14.5 to 130 ng g(-1) for the fly ash, bottom ash and soil, respectively. Daily intakes of PeCBz, HCB and PCBs through soil ingestion and dermal exposure estimated for children ranged 0.33-9.93 (mean 3.14), 0.39-21.1 (mean 4.9) and 6.09-1530 ng/kg bw/day (mean 346), respectively; and these intakes were about 4.7-5.4 times higher than those estimated for adult. The intakes of PeCBz and HCB were relatively low, while those for PCBs exceeded WHO TDI for some samples.

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

    Directory of Open Access Journals (Sweden)

    Xiaodong Bai

    Full Text Available BACKGROUND: 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. METHODOLOGY AND PRINCIPAL FINDINGS: 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. CONCLUSIONS AND SIGNIFICANCE: 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. 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.

  18. Hospital takes customer service to new level, sees positive effect on bottom line.

    Science.gov (United States)

    1997-06-01

    Service with a smile boosts bottom line. Treating co-workers and patients like guests is the linchpin of a whole new philosophy at Bradley Memorial Hospital in Cleveland, TN. Administrators there insist a host of new customer service programs, from cap and gown graduation ceremonies to bunny bucks, has resulted in dramatic financial improvements and more satisfied patients and staff.

  19. DURABILITY OF HARDENED FLY ASH PASTE

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The mechanical properties and durability ( mainly frost-resistance and carbonation resistance ) of fly ash-CaO-CaSO4 .2H2O hardened paste are studied. The relationship among durability of harden ed fly ash paste, the quantity and distribution of hydrates and the initial p aste texture of hardened fly ash paste is presented.

  20. Consumer Financial Protection Bureau

    Science.gov (United States)

    ... more. Find answers to common questions Reach your financial goals For the big financial decisions in your life, we offer free tools ... 2016 Events Field hearing on consumer access to financial records in Salt Lake City, Utah NOV 03, ...

  1. Financial Assistance Information

    Science.gov (United States)

    ... Other Sites: Genetic and Rare Diseases Information Center Financial Assistance Information The National Institutes of Health (NIH) ... area call 900-638-0742. Top of page Financial Aid for Medical Treatments Information on financial aid ...

  2. Treatment Technologies for Hazardous Ashes Generated from Possible Incineration of Navy Waste

    Science.gov (United States)

    1990-10-01

    Resources Projected for Phase 1 of the RTD&E Program: Waste Characterization/ Source Study A-9 A-4 Analytical Tests on Bottom and Fly Ash Generated from...Overall Project Schedule A-4 A-2 Phase I- Waste Characterization/ Source Study Detailed Schedule A-10 A-3 Phase 2: Pilot Rotary Kiln Incineration...fol- lowing RDT&E program is recommended: * Phase 1--Waste Characterization/ Source Study Project future, post-RCRA conformity, Navy waste data needed to

  3. Slamming Testing of Facetted Bottom

    Science.gov (United States)

    2013-11-26

    Technical Report DATES COVERED (From - To) 01 May 2010-31 Aug2013 4. TITLE AND SUBTITLE Slamming Testing of Facetted Bottom 5a. CONTRACT NUMBER...of fast craft are due to slamming , or hydrodynamic impact. A 9 meter long steel / composite hybrid slamming load test facility has been employed for...the purpose of furthering understanding of the slamming phenomenon. This craft is heavily instrumented with strain gages, accelerometers, cameras, an

  4. Mapping of sea bottom topography

    Science.gov (United States)

    Calkoen, C. J.; Wensink, G. J.; Hesselmans, G. H. F. M.

    1992-01-01

    Under suitable conditions the bottom topography of shallow seas is visible in remote sensing radar imagery. Two experiments were performed to establish which remote sensing technique or combination yields optimal imaging of bottom topography and which hydro-meteorological conditions are favorable. A further goal is to gain experience with these techniques. Two experiments were performed over an area in the North Sea near the measuring platform Meetpost Noordwijk (MPN). The bottom topography in the test area is dominated by sand waves. The crests of the sand waves are perpendicular to the coast line and the dominating (tidal-)current direction. A 4x4 sq km wide section of the test area was studied in more detail. The first experiment was undertaken on 16 Aug. 1989. During the experiment the following remote sensing instruments were used: Landsat-Thematic Mapper, and NASA/JPL Airborne Imaging Radar (AIR). The hydro-meteorological conditions; current, wind, wave, and air and water temperature were monitored by MPN, a ship of Rijkswaterstaat (the OCTANS), and a pitch-and-roll WAVEC-buoy. The second experiment took place on 12 July 1992. During this experiment data were collected with the NASA/JPL polarimetric synthetic aperture radar (SAR), and a five-band helicopter-borne scatterometer. Again the hydro-meteorological conditions were monitored at MPN and the OCTANS. Furthermore, interferometric radar data were collected.

  5. Recycling of ashes from biomass combustion. Quantity and composition of ashes and options for recycling of materials; Hergebruik van assen uit biomassaverbranding. Hoeveelheden en samenstelling van de assen en opties voor materiaalhergebruik

    Energy Technology Data Exchange (ETDEWEB)

    Pels, J.R. [ECN Biomassa, Kolen en Milieuonderzoek, Petten (Netherlands)

    2011-05-15

    Sustainable use of biomass for production of heat and power implies that ashes from the thermal conversion of biomass fuels should be utilized and not land filled. This document provides background information with regard to the possibilities for utilization of 'pure' biomass ashes in the Netherlands, that are covered by Sectorplan 24 of the National Waste Management Plan (LAP2). The annual production of these ashes will grow to about 130 kton in 2020. Most of these ashes will be produced in mid-size plants (1-100 MWth). The quality and composition of these ashes shows large variations as a result of the differences in input biomass and the variety of installation types. The optimum use of bottom ashes is the current practice, i.e. as building material in road works, etc. For fly ashes it is not possible to establish one or two general routes for utilization due to the large variety in quality and (chemical) composition. Specific volumes of fly ashes can be used as raw material for fertilizer production or building material. Fly ashes with a high carbon content may be used as fuel, e.g. in cement kilns. The small volumes and the fluctuations in composition prevent effective development of new utilization routes. As a result, most fly ashes and some bottom ashes will still be landfilled. For clean wood ashes it might be reasonable to enable recycling to forests and energy plantations, although the potential is small in the Netherlands. [Dutch] Duurzame inzet van biomassa als brandstof impliceert dat ook residuen een nuttige toepassing vinden en niet op de stortplaatsen eindigen. Het gaat hierbij voornamelijk om vliegassen en bodemassen. Dit rapport betreft de assen die onder Sectorplan 24 vallen van het LAP2 (Landelijk Afvalbeheerplan 2): 'reststoffen van energiewinning uit biomassa, ontstaan in centrales die energie opwekken door thermische verwerking in de vorm van verbranding, vergassing of pyrolyse van biomassa'. Het gaat hierbij om

  6. Characterization of hot-mix asphalt concrete containing municipal solid waste incinerator ash using the dynamic modulus (E) test

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, H.F. [Sultan Qaboos Univ., Muscat (Oman). College of Engineering

    2007-07-01

    In 2001, approximately 229 million tons of municipal solid waste (MSW) were produced in the United States. MSW consists of items such as paper, grass clippings, furniture, clothing, bottles, food scraps, appliances, paint, and batteries. MSW incinerator ash is the by-product produced during the combustion of municipal solid waste in combustor facilities and has two components, namely bottom ash and fly ash. To reduce the disposal problem, the incinerators are used to reduce the volume and weight of MSW. This is usually a self-sustained process using the waste as a fuel resulting in as much as a 90 and 75 per cent reduction in volume and weight, respectively. This paper presented the results of a study that investigated the use of incinerator ash as a partial replacement of fine aggregate in hot-mix asphalt concrete. MSW incinerator ash was collected from an incinerator facility at Sultan Qaboos University in Oman and a physical and chemical characterization of the ash was conducted. MSW ash was used in the mixture to replace fine aggregate with a percentage ranging from 0 to 40 per cent, by total aggregate weight. The mixes were designed using the Marshall mix design method and the dynamic modulus test was conducted on samples prepared at optimum asphalt contents for mixes containing different percentage of ash and at different temperatures and frequencies. Master curves for different percentages of ash in the mix were developed from the testing results. It was found that the Marshall mix design results for the mixes containing MSW ash indicated a decrease in stability, and specific gravity, and an increase in air voids. 18 refs., 10 figs.

  7. Financial Literacy and Financial Planning in France.

    OpenAIRE

    Luc Arrondel; Majdi Debbich; Frédérique Savignac

    2013-01-01

    How are people financially literate in France? We address this question using the PATER survey and following the Lusardi and Mitchell (2011c) approach. We find that some subpopulations are less financially literate than others: women, young and old people as well as less-educated people are more likely to face difficulties when dealing with fundamental financial concepts such as risk diversification, inflation and interest compounding. We also find some differences in financial knowledge depe...

  8. Financial Village Standing in Indonesian Financial System

    Directory of Open Access Journals (Sweden)

    Herry Purnomo

    2015-12-01

    Full Text Available Financial resources of the village that are sourced from a country or a Regional Finance Financial based Law Number 6 Year 2014 of The Village is the mandate of the law that must be allocated to the village. The interconnectedness of the financial position of the village in the financial system of the country or Region concerned the Financial administrative and territorial relations, and there is no setting directly regarding the finances of the village as part of the financial system of the country or the financial area. In respect of the elements of the crime of corruption deeds against financial irregularities of the village there are still disagreements on the interpretation of the law in trapping the perpetrators of corruption on the village chief that implies not satisfy the principle of legality and legal certainty in the ruling of the matter of financial irregularities. In fact, many of the village chief or Councilor caught the criminal offence of corruption over the use of financial irregularities. This research analyzes How the financial position of the village in the financial system of the country or region, as well as whether the financial resources of the village is derived from the state budget or region budget managed in village budget belongs to the category of village finances and whether tort against the financial management of the village can be categorized as a criminal act corruption. How To Cite: Purnomo, H. (2015. Financial Village Standing in Indonesian Financial System. Rechtsidee, 2(2, 121-140. doi:http://dx.doi.org/10.21070/jihr.v2i2.81

  9. Financial Stress Indices and Financial Crises

    NARCIS (Netherlands)

    Vermeulen, Robert; Hoeberichts, Marco; Vasicek, Borek; Zigraiova, Diana; Smidkova, Katerina; de Haan, Jakob

    2015-01-01

    This paper develops a Financial Stress Index (FSI) for 28 OECD countries and examines its relationship to crises using a novel database for financial crises. A stress index measures the current state of stress in the financial system and summarizes it in a single statistic. Our results suggest that

  10. 1999 international ash utilization symposium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    112 papers were presented covering various aspects of the utilization of coal and other combustion products. Topics included fundamental chemistry and mineralogy, new products, health and environmental aspects, economic development issues, agricultural and mine reclamation applications, concrete and cement, and fly ash beneficiation technologies. Selected papers will be published in the journal 'Fuel'.

  11. Ash chemistry in MSW incineration plants: Advanced characterization and thermodynamic considerations

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, Flemming J.; Laursen, Karin; Arvelakis, S. (and others)

    2004-07-15

    A number of ash samples where collected at four Danish municipal solid waste incineration (MSWI) plants. Samples of bottom ash/slag, 2nd-3rd pass ashes and ESP/E-filter ash were collected at the plants. The ashes were analyzed by a number of standard chemical analyses, and a number of advanced analytical techniques. The wet chemical analyses of the different ash fractions revealed that residual ash is formed on the grate by interaction of the main ash forming elements, Al, Ca, Fe and Si. Some of this ash is entrained from the grate and carried with the flue gas along the flue gas duct, where volatile species of K, Na, Pb, Zn, Cl and S starts to condense heterogeneously on the fly ash, thereby causing a dilution of the main ash forming elements. When compared plant-by-plant, the ash chemical analyses showed that the plant with the highest S-content in the fly ash is the one with the most often operational problems in relation to deposition, while a high Cl-content is indicative of a high corrosive potential. An existing Computer Controlled Scanning Electron Microscopy (CCSEM) algorithm was extended with chemical classes covering Pb- and Zn-rich phases. This has made it possible also to analyze MSW-derived ashes by use of CCSEM. Representative samples of 2nd-3rd pass and ESP/E-filter ashes from the four plants have been analyzed by Quantitative X-Ray Diffraction (QXRD) analysis. Only a few crystalline phases were identified: KCl, NaCl, CaSO{sub 4}, SiO{sub 2} and CaCO{sub 3} being the main ones. No crystalline phases containing Pb or Zn were identified by QXRD. A comparison between CCSEM and QXRD revealed the expected surface nature of the CCSEM analysis. Samples of 2nd-3rd pass and ESP/E-filter ash from the four plants where investigated for melting behavior in the Simultaneous Thermal Analyzer (STA). It was shown that it is possible to quantify the melting behavior of these ashes, and that the melting goes on in two steps (salts followed by silicates/oxides). The

  12. Use of Incineration MSW Ash: A Review

    Directory of Open Access Journals (Sweden)

    Charles H. K. Lam

    2010-07-01

    Full Text Available This study reviews the characteristics of municipal solid waste incineration (MSWI ashes, with a main focus on the chemical properties of the ashes. Furthermore, the possible treatment methods for the utilization of ash, namely, separation processes, solidification/stabilization and thermal processes, are also discussed. Seven types of MSWI ash utilization are reviewed, namely, cement and concrete production, road pavement, glasses and ceramics, agriculture, stabilizing agent, adsorbents and zeolite production. The practical use of MSWI ash shows a great contribution to waste minimization as well as resources conservation.

  13. Development of Bottom Oil Recovery Systems. Revised

    Science.gov (United States)

    2014-02-01

    Athos I), open-ocean (T/V Prestige), and oil-field deep ocean drilling (Deepwater Horizon) related spills, the problems associated with tracking... mud . Probably the least sensitive bottom types are sand and mud bottoms in areas that already suffer from pollution such as industrial areas. Note...Capping Coral Reef Sea Grass Beds Kelp Forest Rocky Bottom Sand Mud Recommended Provisional Not Recommended Development of Bottom Oil Recovery Systems

  14. 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.

  15. Financial Literacy and Financial Planning in France

    Directory of Open Access Journals (Sweden)

    Luc Arrondel

    2013-07-01

    Full Text Available We study financial literacy in France using the PATER survey and following the Lusardi and Mitchell (2011c approach. We find that some subpopulations are less financially literate than others: women, young and old people as well as less-educated people are more likely to face difficulties when dealing with fundamental financial concepts such as risk diversification and inflation and interest compounding. We also find some differences in financial knowledge depending on the political opinion of the respondents. Finally we show that these differences in financial knowledge are correlated with differences in the propensity to plan: people who score higher on the financial literacy questions are more likely to be engaged in the preparation of a clearly defined financial plan.

  16. Environmental & Health Hazards of Fly Ash & SOx from FBC Power Plant at Khanote

    Directory of Open Access Journals (Sweden)

    Shaheen Aziz

    2010-12-01

    Full Text Available Lakhra coal reserves are estimated to about 1328 million tones. Most of mined Coal in Pakistan has been used for power generation in addition to some other uses. Lakhra coal (lignite reserves are very high in sulphur content, moisture and ash that not only cause environmental pollution but also cause operational problems. In order to avoid environmental & operational problems, clean coal technology (FBC technology has been used globally because of its merits. In FBC power plant, sulphure is captured by using limestone. In Pakistan, 3x50MW power plant was installed at Khanote to utilize the lakhra coal for the first time. The present study is focused on formation of ash & sulphur. In the FBC power plant at khanote, the generation rate of fly ash & bottom ash was 55680 m3/hr and 16550 m3/hr respectively. Unexpected huge amount of ash causes environmental problem in shape of particulate matter that causes respiratory diseases in the workers. It also affects nearby villages by polluting agricultural land, cattles & habitants. The present research not only indentifies the risks on the basis of extensive experimental analysis, but also proposed solution for its proper disposal.

  17. "Triple-bottom-line" assessment of urban stormwater projects.

    Science.gov (United States)

    Taylor, A C; Fletcher, T D

    2006-01-01

    New guidelines have been developed and trialled in Australia to assist urban stormwater managers to assess options for projects that aim to improve urban waterway health. These guidelines help users to examine the financial, ecological and social dimensions of projects (i.e., the so-called "triple-bottom-line"). Features of the assessment process described in the guidelines include use of multi criteria analysis, input from technical experts as well as non-technical stakeholders, and provision of three alternative levels of assessment to suit stormwater managers with differing needs and resources. This paper firstly provides a background to the new guidelines and triple-bottom-line assessment. The assessment methodology promoted in the new guidelines is then briefly summarised. This methodology is compared and contrasted with European guidelines from the "SWARD" project that have been primarily developed for assessing the relative sustainability of options involving urban water supply and sewerage assets. Finally, the paper discusses how assessment methodologies that evaluate the financial, ecological and social dimensions of projects can, under some circumstances, be used to evaluate the relative progress of options for urban water management on a journey towards the widely pursued, but vaguely defined goal of "sustainable development".

  18. Financial Sector Assessment : Malaysia

    OpenAIRE

    World Bank

    2013-01-01

    Malaysia, as many of its Asian neighbors, experienced significant macro/financial distress in the late 1990s. The transformed and strengthened financial sector has been able to weather the recent global financial crisis well. Financial market intermediaries reliance on cross-border and interbank funding remains limited. Banking institutions are well capitalized and are expected to be able...

  19. Consumer Financial Protection Bureau

    Science.gov (United States)

    ... Money as You Grow Navigating the Military Financial Lifecycle Owning a Home Paying for College Planning for Retirement Browse answers to hundreds of financial questions. Ask CFPB Have an issue with a financial product? Submit a complaint Get your financial well-being ...

  20. Financial Risk Management

    OpenAIRE

    Catalin-Florinel Stanescu; Laurentiu Mircea Simion

    2011-01-01

    Concerns about the financial risk is increasing. In this climate, companies of all types and sizes want a robust framework for financial risk management to meet compliance requirements, contribute to better decision making and increase performance. Financial risk management professionals working with financial institutions and other corporate clients to achieve these objectives.

  1. Interspecific variation in resistance to emerald ash borer (Coleoptera: Buprestidae) among North American and Asian ash (Fraxinus spp.).

    Science.gov (United States)

    Rebek, Eric J; Herms, Daniel A; Smitley, David R

    2008-02-01

    We conducted a 3-yr study to compare the susceptibility of selected North American ash and an Asian ash species to emerald ash borer, Agrilus planipennis Fairmaire, an invasive wood-boring beetle introduced to North America from Asia. Because of a coevolutionary relationship between Asian ashes and emerald ash borer, we hypothesized an Asian ash species, Manchurian ash, is more resistant to the beetle than its North American congeners. Consistent with our hypothesis, Manchurian ash experienced far less mortality and yielded far fewer adult beetles than several cultivars of North American green and white ash. Surprisingly, a black ash (North American) x Manchurian ash hybrid was highly susceptible to emerald ash borer, indicating this cultivar did not inherit emerald ash borer resistance from its Asian parent. A corollary study investigated the efficacy of soil-applied imidacloprid, a systemic, neonicotinoid insecticide, for controlling emerald ash borer in each of the five cultivars. Imidacloprid had no effect on emerald ash borer colonization of Manchurian ash, which was low in untreated and treated trees. In contrast, imidacloprid did enhance survival of the North American and hybrid cultivars and significantly reduced the number of emerald ash borer adults emerging from green and white ash cultivars. We identify a possible mechanism of resistance of Manchurian ash to emerald ash borer, which may prove useful for screening, selecting, and breeding emerald ash borer-resistant ash trees.

  2. A scanning electron microscopy study of ash, char, deposits and fuels from straw combustion and co-combustion of coal and straw

    Energy Technology Data Exchange (ETDEWEB)

    Sund Soerensen, H.

    1998-07-01

    The SEM-study of samples from straw combustion and co-combustion of straw and coal have yielded a reference selection of representative images that will be useful for future comparison. The sample material encompassed potential fuels (wheat straw and grain), bottom ash, fly ash and deposits from straw combustion as well as fuels (coal and wheat straw), chars, bottom ash, fly ash and deposits from straw + coal co-combustion. Additionally, a variety of laboratory ashes were studied. SEM and CCSEM analysis of the samples have given a broad view of the inorganic components of straw and of the distribution of elements between individual ash particles and deposits. The CCSEM technique does, however, not detect dispersed inorganic elements in biomass, so to get a more complete visualization of the distribution of inorganic elements additional analyses must be performed, for example progressive leaching. In contrast, the CCSEM technique is efficient in characterizing the distribution of elements in ash particles and between ash fractions and deposits. The data for bottom ashes and fly ashes have indicated that binding of potassium to silicates occurs to a significant extent. The silicates can either be in the form of alumino-silicates or quartz (in co-combustion) or be present as straw-derived amorphous silica (in straw combustion). This process is important for two reasons. One is that potasium lowers the melting point of silica in the fly ash, potentially leading to troublesome deposits by particle impaction and sticking to heat transfer surfaces. The other is that the reaction between potassium and silica in the bottom ash binds part of the potassium meaning that it is not available for reaction with chlorine or sulphur to form KCl or K{sub 2}SO{sub 4}. Both phases are potentially troublesome because they can condense of surfaces to form a sticky layer onto which fly ash particles can adhere and by inducing corrosion beneath the deposit. It appears that in the studied

  3. Essays on financial liberalization

    OpenAIRE

    Bumann, Silke

    2015-01-01

    This thesis investigates the effect of financial liberalization on economic growth, income inequality and financial instability. Chapter 1 describes aim and scope of the thesis. Chapter 2 provides a meta-analysis of the literature on financial liberalization and economic growth. It is found that financial liberalization has a positive, albeit weak effect on growth. Chapter 3 presents a theoretical model to study the relationship between financial liberalization and income inequality. The mode...

  4. Index of Financial Inclusion

    OpenAIRE

    Mandira Sarma

    2008-01-01

    The promotion of an inclusive financial system is considered a policy priority in many countries. While the importance of financial inclusion is widely recognized, the literature lacks a comprehensive measure that can be used to measure the extent of financial inclusion across economies. This paper attempts to fill this gap by proposing an index of financial inclusion (IFI). The IFI is a multi-dimensional index that captures information on various dimensions of financial inclusion in one sing...

  5. Enrichment of trace elements in bottom ash from coal oxy-combustion: Effect of coal types

    CSIR Research Space (South Africa)

    Oboirien, BO

    2016-09-01

    Full Text Available In this study, the enrichment of trace elements in two coals under air and oxy-combustion conditions was studied. Twenty-one trace elements were evaluated. The two coal samples had a different concentration for the 21 trace elements, which was due...

  6. Leaching from waste incineration bottom ashes treated in a rotary kiln

    DEFF Research Database (Denmark)

    Hyks, Jiri; Nesterov, Igor; Mogensen, Erhardt

    2011-01-01

    their detection limits; no effects of the thermal treatment on leachability of these metals were observed. The leaching of Cl, dissolved organic carbon (DOC), Cu and Pb decreased by at least one order of magnitude after the thermal treatment. This could be explained by evaporation (Cl) and by a better burnout...

  7. Quantification of the resource recovery potential of municipal solid waste incineration bottom ashes

    DEFF Research Database (Denmark)

    Allegrini, Elisa; Maresca, Alberto; Olsson, Mikael Emil

    2014-01-01

    data, all individual flows (representing different grain size fractions) within the recovery facility were quantified, (ii) the resource potential of ferrous (Fe) and non-ferrous (NFe) metals as well as rare earth elements (REE) was determined, (iii) recovery efficiencies were quantified for scrap...

  8. Ultrasonic ash/pyrite liberation

    Energy Technology Data Exchange (ETDEWEB)

    Yungman, B.A.; Buban, K.S.; Stotts, W.F.

    1990-06-01

    The objective of this project was to develop a coal preparation concept which employed ultrasonics to precondition coal prior to conventional or advanced physical beneficiation processes such that ash and pyrite separation were enhanced with improved combustible recovery. Research activities involved a series of experiments that subjected three different test coals, Illinois No. 6, Pittsburgh No. 8, and Upper Freeport, ground to three different size fractions (28 mesh [times] 0, 200 mesh [times] 0, and 325 mesh [times] 0), to a fixed (20 kHz) frequency ultrasonic signal prior to processing by conventional and microbubble flotation. The samples were also processed by conventional and microbubble flotation without ultrasonic pretreatment to establish baseline conditions. Product ash, sulfur and combustible recovery data were determined for both beneficiation processes.

  9. Utilization Of Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    S. D. Nagrale

    2012-07-01

    Full Text Available India is a major rice producing country, and the husk generated during milling is mostly used as a fuel in the boilers for processing paddy, producing energy through direct combustion and / or by gasification. About 20 million tones of Rice Husk Ash (RHA is produced annually. This RHA is a great environment threat causing damage to the land and the surrounding area in which it is dumped. Lots of ways are being thought of for disposing them by making commercial use of this RHA. RHA can be used as a replacement for concrete (15 to 25%.This paper evaluates how different contents of Rice Husk Ash added to concrete may influence its physical and mechanical properties. Sample Cubes were tested with different percentage of RHA and different w/c ratio, replacing in mass the cement. Properties like Compressive strength, Water absorption and Slump retention were evaluated.

  10. 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.

  11. Deposition or not? The fate of volcanic ash after aggregation processes

    Science.gov (United States)

    Mueller, Sebastian B.; Kueppers, Ulrich; Wadsworth, Fabian B.; Ayris, Paul M.; Casas, Ana S.; Cimarelli, Corrado; Ametsbichler, Jonathan; Delmelle, Pierre; Taddeucci, Jacopo; Jacob, Michael; Dingwell, Donald B.

    2017-04-01

    In the course of explosive volcanic eruptions, large amounts of ash are released into the atmosphere and may subsequently pose a threat to infrastructure, such as aviation industry. Ash plume forecasting is therefore a crucial tool for volcanic hazard mitigation but may be significantly affected by aggregation, altering the aerodynamic properties of particles. Models struggle with the implementation of aggregation since external conditions promoting aggregation have not been completely understood; in a previous study we have shown the rapid generation of ash aggregates through liquid bonding via the use of fluidization bed technology and further defined humidity and temperature ranges necessary to trigger aggregation. Salt (NaCl) was required for the recovery of stable aggregates, acting as a cementation agent and granting aggregate cohesion. A numerical model was used to explain the physics behind particle aggregation mechanisms and further predicted a dependency of aggregation efficiency on liquid binder viscosity. In this study we proof the effect of viscosity on particle aggregation. HCl and H2SO4 solutions were diluted to various concentrations resulting in viscosities between 1 and 2 mPas. Phonolitic and rhyolitic ash samples as well as soda-lime glass beads (serving as analogue material) were fluidized in the ProCell Lab® of Glatt Ingenieurtechnik GmbH and treated with the acids via a bottom-spray technique. Chemically driven interaction between acid liquids and surfaces of the three used materials led to crystal precipitation. Salt crystals (e.g. NaCl) have been confirmed through scanning electron microscopy (SEM) and leachate analysis. Both volcanic ash samples as well as the glass beads showed a clear dependency of aggregation efficiency on viscosity of the sprayed HCl solution. Spraying H2SO4 provoked a collapse of the fluidized bed and no aggregation has been observed. This is accounted by the high hygroscopicity of H2SO4. Dissolving CaCl2 (known to be

  12. Financial planning

    OpenAIRE

    Χατζηγώγου, Αρτεμις Π.

    2003-01-01

    Σκοπός της μελέτης αυτής, είναι η συγκέντρωση όλων των στοιχείων εκείνων που συνθέτουν μια οργανωμένη διαδικασία έρευνας, που είναι γνωστή ως Financial Planning. Θα μπορούσαμε εναλλακτικά να πούμε, ότι βασικά ο χρηματοοικονομικός σχεδιασμός προγραμματίζει, εξευρίσκει και χρησιμοποιεί τα κεφάλαια με τέτοιο τρόπο ώστε η συνεισφορά τους να είναι μεγαλύτερη στην αποτελεσματική λειτουργία της οικονομικής μονάδας. Παρέχει τις γνώσεις των χρηματιστικών αγορών από όπου αντλούνται τα κεφάλαια. Οδηγεί ...

  13. Geopolymer Mortar with Fly Ash

    Directory of Open Access Journals (Sweden)

    Saloma

    2016-01-01

    Full Text Available The cement industry accounts for about 7% of all CO2 emissions caused by humans. Therefore, it is necessary to find another material in order to support sustainable material. An alternative way is replacing cement material with alternative material as fly ash. Fly ash as binder need to be added alkaline activator in the form of sodium silicate (Na2SiO3 or potassium silicate (K2SiO3 and sodium hydroxide (NaOH or potassium hydroxide (KOH. The purpose of this research is to analyze the effect of activator liquid concentration on geopolymer mortar properties and to know the value of compressive strength. Molarity variation of NaOH are 8, 12, 14, and 16 M with ratio of Na2SiO3/NaOH = 1.0. Ratio of sand/fly ash = 2.75 and ratio of activator/fly ash = 0.8. The cube-shaped specimen 50 × 50 × 50 mm is cured by steam curing with a temperature of 60°C for 48 hours. The experimental result of fresh mortar reported that the molarity of NaOH affect the slump flow and setting time, higher of NaOH produces the smaller value of slump and the faster time of setting. The experimental of density results reported that the increase of specific gravity when the molarity of NaOH increased. The experimental results of the compressive strength are showed that the maximum compressive strength of geopolymer mortar 14 M is 10.06 MPa and the lowest compressive strength produced by geopolymer mortar 8 M is 3.95 MPa. Testing the compressive strength of geopolymer mortar 16 M produces compressive strength lower than 14 M geopolymer mortar is 9.16 MPa.

  14. Vitrification of municipal solid waste incineration fly ash using biomass ash as additives.

    Science.gov (United States)

    Alhadj-Mallah, Moussa-Mallaye; Huang, Qunxing; Cai, Xu; Chi, Yong; Yan, JianHua

    2015-01-01

    Thermal melting is an energy-costing solution for stabilizing toxic fly ash discharged from the air pollution control system in the municipal solid waste incineration (MSWI) plant. In this paper, two different types of biomass ashes are used as additives to co-melt with the MSWI fly ash for reducing the melting temperature and energy cost. The effects of biomass ashes on the MSWI fly ash melting characteristics are investigated. A new mathematical model has been proposed to estimate the melting heat reduction based on the mass ratios of major ash components and measured melting temperature. Experimental and calculation results show that the melting temperatures for samples mixed with biomass ash are lower than those of the original MSWI fly ash and when the mass ratio of wood ash reaches 50%, the deformation temperature (DT), the softening, hemisphere temperature (HT) and fluid temperature (FT) are, respectively, reduced by 189°C, 207°C, 229°C, and 247°C. The melting heat of mixed ash samples ranges between 1650 and 2650 kJ/kg. When 50% wood ash is mixed, the melting heat is reduced by more than 700 kJ/kg for the samples studied in this paper. Therefore, for the vitrification treatment of the fly ash from MSW or other waste incineration plants, wood ash is a potential fluxing assistant.

  15. 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