WorldWideScience

Sample records for heat carrier ash

  1. Ash reduction system using electrically heated particulate matter filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J; He, Yongsheng [Sterling Heights, MI

    2011-08-16

    A control system for reducing ash comprises a temperature estimator module that estimates a temperature of an electrically heated particulate matter (PM) filter. A temperature and position estimator module estimates a position and temperature of an oxidation wave within the electrically heated PM filter. An ash reduction control module adjusts at least one of exhaust flow, fuel and oxygen levels in the electrically heated PM filter to adjust a position of the oxidation wave within the electrically heated PM filter based on the oxidation wave temperature and position.

  2. Is metal nanofluid reliable as heat carrier?

    Science.gov (United States)

    Nine, Md J; Chung, Hanshik; Tanshen, Md Riyad; Osman, N A B Abu; Jeong, Hyomin

    2014-05-30

    A pre- and post experimental analysis of copper-water and silver-water nanofluids are conducted to investigate minimal changes in quality of nanofluids before and after an effective heat transfer. A single loop oscillating heat pipe (OHP) having inner diameter of 2.4mm is charged with aforementioned nanofluids at 60% filling ratio for end to end heat transfer. Post experimental analysis of both nanofluids raises questions to the physical, chemical and thermal stability of such suspension for hazardless uses in the field of heat transfer. The color, deposition, dispersibility, propensity to be oxidized, disintegration, agglomeration and thermal conductivity of metal nanofluids are found to be strictly affected by heat transfer process and vice versa. Such degradation in quality of basic properties of metal nanofluids implies its challenges in practical application even for short-term heat transfer operations at oxidative environment as nano-sized metal particles are chemically more unstable than its bulk material. The use of the solid/liquid suspension containing metal nanoparticles in any heat exchanger as heat carrier might be detrimental to the whole system.

  3. Binary Effect of Fly Ash and Palm Oil Fuel Ash on Heat of Hydration Aerated Concrete

    Directory of Open Access Journals (Sweden)

    Taha Mehmannavaz

    2014-01-01

    Full Text Available The binary effect of pulverized fuel ash (PFA and palm oil fuel ash (POFA on heat of hydration of aerated concrete was studied. Three aerated concrete mixes were prepared, namely, concrete containing 100% ordinary Portland cement (control sample or Type I, binary concrete made from 50% POFA (Type II, and ternary concrete containing 30% POFA and 20% PFA (Type III. It is found that the temperature increases due to heat of hydration through all the concrete specimens especially in the control sample. However, the total temperature rises caused by the heat of hydration through both of the new binary and ternary concrete were significantly lower than the control sample. The obtained results reveal that the replacement of Portland cement with binary and ternary materials is beneficial, particularly for mass concrete where thermal cracking due to extreme heat rise is of great concern.

  4. Binary effect of fly ash and palm oil fuel ash on heat of hydration aerated concrete.

    Science.gov (United States)

    Mehmannavaz, Taha; Ismail, Mohammad; Radin Sumadi, Salihuddin; Rafique Bhutta, Muhammad Aamer; Samadi, Mostafa; Sajjadi, Seyed Mahdi

    2014-01-01

    The binary effect of pulverized fuel ash (PFA) and palm oil fuel ash (POFA) on heat of hydration of aerated concrete was studied. Three aerated concrete mixes were prepared, namely, concrete containing 100% ordinary Portland cement (control sample or Type I), binary concrete made from 50% POFA (Type II), and ternary concrete containing 30% POFA and 20% PFA (Type III). It is found that the temperature increases due to heat of hydration through all the concrete specimens especially in the control sample. However, the total temperature rises caused by the heat of hydration through both of the new binary and ternary concrete were significantly lower than the control sample. The obtained results reveal that the replacement of Portland cement with binary and ternary materials is beneficial, particularly for mass concrete where thermal cracking due to extreme heat rise is of great concern.

  5. A study of the properties of the mineral residue of thermal pyrolysis of shales produced in an installation with a solid heat carrier

    Energy Technology Data Exchange (ETDEWEB)

    Sidorovich, Ya.I.; Kopachinskiy, K.F.; Lubentsova, V.N.; Makitra, R.G.; Stel' makh, G.P.

    1980-01-01

    The ash of menilite shales for Carpathia, produced in a laboratory stand with a solid heat carrier, was studied to solve the problem of utilization of its mineral mass. The possibility is demonstrated of using the ash for the production of Portland cement and for construction ceramics. The best results are obtained with the processing of the ash at a temperature of approximately 720 degrees.

  6. Metal-Organic Heat Carrier Nanofluids

    Energy Technology Data Exchange (ETDEWEB)

    McGrail, B. Peter; Thallapally, Praveen K.; Blanchard, Jeremy; Nune, Satish K.; Jenks, Jeromy WJ; Dang, Liem X.

    2013-09-01

    Nanofluids, dispersions of metal or oxide nanoparticles in a base working fluid, are being intensively studied due to improvements they offer in thermal properties of the working fluid. However, these benefits have been erratically demonstrated and proven impacts on thermal conductivity are modest and well described from long-established effective medium theory. In this paper, we describe a new class of metal-organic heat carrier (MOHC) nanofluid that offers potential for a larger performance boost in thermal vapor-liquid compression cycles. MOHCs are nanophase porous coordination solids designed to reversibly uptake the working fluid molecules in which the MOHCs are suspended. Additional heat can be extracted in a heat exchanger or solar collector from the endothermic enthalpy of desorption, which is then released as the nanofluid transits through a power generating device such as a turboexpander. Calculations for an R123 MOHC nanofluid indicated potential for up to 15% increase in power output. Capillary tube experiments show that liquid-vapor transitions occur without nanoparticle deposition on the tube walls provided entrance Reynolds number exceeds approximately 100.

  7. Combustion Air Pre-heating from Ash Sensible Heat in Municipal Waste Incineration Systems

    Directory of Open Access Journals (Sweden)

    Zakariya Kaneesamkandi

    2014-01-01

    Full Text Available Heat recovery from bottom ash is more important in municipal waste combustion systems than in any other solid fuel combustion since almost 50% of it comprises of non-combustibles. In this study, an ash cooling system using air as the cooling medium has been modeled for pre-heating the combustion air. Air cooling has several advantages over water cooling methods. The study involves modeling using Gambit tool and is solved with the fluent solver. Municipal solid waste incineration systems have the advantage of being located near the waste collection area apart from the high volume reduction ratio. Improvements in the emission control systems and combustion technology can make incineration a highly feasible disposal method. Low furnace temperature due to heat losses through fuel moisture loss and ash sensible heat loss has been a disadvantage with these systems. In this study, a small percentage of the combustion air is pre-heated in a non-contact type heat exchanger and its effect on the available energy of combustion gases at the evaporator outlet is studied. The study is performed for two different waste samples. Results indicate significant increase in available energy at the evaporator outlet and better relative performance for the lower grade fuel. A comparison is made with similar methods reported in the literature along with a brief discussion on the methodologies adopted. The results confirm the importance of installing ash sensible heat recovery mechanism for waste incineration systems as well as the feasibility of the air based method.

  8. 76 FR 3077 - Notice of Decision To Revise a Heat Treatment Schedule for Emerald Ash Borer

    Science.gov (United States)

    2011-01-19

    ... Emerald Ash Borer AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Notice. SUMMARY: We are advising the public of our decision to revise a heat treatment schedule for the emerald ash borer... revised treatment schedule will be sufficient to treat emerald ash borer. DATES: Effective Date:...

  9. Borehole model for simulation transport geothermal heat with heat pipe system and with forced circulation of heat carrier

    Directory of Open Access Journals (Sweden)

    Lenhard Richard

    2012-04-01

    Full Text Available In the call OPVaV-2008/2.2/01-SORO Operational Programme Research and Development - knowledge and technology transfer from research and development into practice (ITMS-26220220057, whose strategic goal is "Device to use low-potential geothermal heat without forced circulation of heat carrier deep in the well "in the Department of Energy laboratory techniques to construct a simulator of transport low potential of geothermal energy in comparative test-drilling in the laboratory. The article describes a device that was designed as a scale model of two deep boreholes each of which withdraws the earth's heat by heat transfer technology and heat carrier. Device using forced circulation of heat carrier will respond in the construction of equipment currently used to transport heat from deep borehole. As the heat carrier will be used CO2. Facilities without using forced circulation of heat carrier, the new technology, which will be used as heat carrier ammonia (NH3.

  10. Heat sterilization of ash (Fraxinus spp.) firewood : heat-treating options, temperature monitoring and thermal verification

    Science.gov (United States)

    Xiping Wang; Richard Bergman; T. Mace

    2010-01-01

    Because of the potential risk associated with moving emerald ash borer (EAB)-infested firewood, the interstate movement of all hardwood firewood in the USA is currently restricted under the Federal quarantine. Communities and firewood producers are now faced with decisions on how to treat their firewood for interstate commerce. The new US Federal regulations for heat...

  11. Volcanic ash particles as carriers of remanent magnetization in deep-sea sediments from the Kerguelen Plateau

    Science.gov (United States)

    Heider, Franz; Ko¨rner, Ulrike; Bitschene, Peter

    1993-07-01

    Carbonate sediments from the Kerguelen Plateau (ODP Leg 120) of Eocene to Pliocene age were investigated with rock magnetic, petrographic and geochemical methods to determine the carriers of remanent magnetization. Magnetic methods showed that the major magnetic minerals were titanomagnetites slightly larger than single domain particles. Submicrometre to micrometre-size grains of titanomagnetite were identified as inclusions in volcanic glass particles or as crystals in lithic clasts. Volcanic fallout ash particles formed the major fraction of the magnetic extract from each sediment sample. Three groups of volcanic ashes were identified: trachytic ashes, basaltic ashes with sideromelane and tachylite shards, and palagonitic ashes. These three groups could be equally well defined based on their magnetic hysteresis properties and alternating field demagnetization curves. The highest coercivities of all samples were found for the tachylite, due to the submicrometre-size titanomagnetite inclusions in the matrix. Trachytic ashes had intermediate magnetic properties between the single-domain-type tachylites and the palagonitic (altered) basaltic ashes with low coercivities. Samples which contained mixtures of these different volcanic ashes could be distinguished from the three types of ashes based on their magnetic characteristics. There was neither evidence of biogenic magnetofossils in the transmission electron micrographs nor did we find magnetic particles derived from continental Antarctica. The presence of dispersed volcanic fallout ashes between visible ash layers suggests continuous explosive volcanic activity on the Kerguelen Plateau in the South Indian Ocean since the early Eocene. The continuous fallout of volcanic ash from explosive volcanism on the Kerguelen Archipelago is the source of the magnetic particles and thus responsible for the magnetostratigraphy of the nannofossil oozes drilled during Leg 120.

  12. Speciation of zinc in municipal solid waste incineration fly ash after heat treatment: an X-ray absorption spectroscopy study.

    Science.gov (United States)

    Struis, Rudolf P W J; Ludwig, Christian; Lutz, Harald; Scheidegger, André M

    2004-07-01

    Fly ash is commonly deposited in special landfills as it contains toxic concentrations of heavy metals, such as Zn, Pb, Cd, and Cu. This study was inspired by our efforts to detoxify fly ash from municipal solid waste incineration by thermal treatment to produce secondary raw materials suited for reprocessing. The potential of the thermal treatment was studied by monitoring the evaporation rate of zinc from a certified fly ash (BCR176) during heating between 300 and 950 degrees C under different carrier gas compositions. Samples were quenched at different temperatures for subsequent investigation with X-ray absorption spectroscopy (XAS). The XAS spectra were analyzed using principal component analysis (PCA), target transformation (TT), and linear combination fitting (LCF) to analyze the major Zn compounds in the fly ash as a function of the temperature. The original fly ash comprised about 60% zinc oxides mainly in the form of hydrozincite (Zn5(OH)6(CO3)2) and 40% inerts like willemite (Zn2SiO4) and gahnite (ZnAl2O4) in a weight ratio of about 3:1. At intermediate temperatures (550-750 degrees C) the speciation underlines the competition between indigenous S and Cl with solid zinc oxides to form either volatile ZnCl2 or solid ZnS. ZnS then transformed into volatile species at about 200 degrees C higher temperatures. The inhibiting influence of S was found absent when oxygen was introduced to the inert carrier gas stream or chloride-donating alkali salt was added to the fly ash.

  13. Heating subsurface formations by oxidizing fuel on a fuel carrier

    Energy Technology Data Exchange (ETDEWEB)

    Costello, Michael; Vinegar, Harold J.

    2012-10-02

    A method of heating a portion of a subsurface formation includes drawing fuel on a fuel carrier through an opening formed in the formation. Oxidant is supplied to the fuel at one or more locations in the opening. The fuel is combusted with the oxidant to provide heat to the formation.

  14. The Thermal Behavior of Coal—Ash Deposits on Heat Exchangers

    Institute of Scientific and Technical Information of China (English)

    JamesL.S.Chen; EverettR.Ramer

    1994-01-01

    A theoretical model for predicting the thermal behavior of coal-ash deposits on heat exchangers is developed.The heat transfer modes of heat conduction,converction,and thermal radiation are considered for the system.The effective thermal conductivities and emissivities of the ash deposits are temperature dependet,Heat fluxeds and dimensionless temperatures in the three layers(loose,sintered,and fused) of the ash deposit are determined.Results are presented for the first two rows of tubes in aligned and staggered tube banks.

  15. Size limits for rounding of volcanic ash particles heated by lightning.

    Science.gov (United States)

    Wadsworth, Fabian B; Vasseur, Jérémie; Llewellin, Edward W; Genareau, Kimberly; Cimarelli, Corrado; Dingwell, Donald B

    2017-03-01

    Volcanic ash particles can be remelted by the high temperatures induced in volcanic lightning discharges. The molten particles can round under surface tension then quench to produce glass spheres. Melting and rounding timescales for volcanic materials are strongly dependent on heating duration and peak temperature and are shorter for small particles than for large particles. Therefore, the size distribution of glass spheres recovered from ash deposits potentially record the short duration, high-temperature conditions of volcanic lightning discharges, which are hard to measure directly. We use a 1-D numerical solution to the heat equation to determine the timescales of heating and cooling of volcanic particles during and after rapid heating and compare these with the capillary timescale for rounding an angular particle. We define dimensionless parameters-capillary, Fourier, Stark, Biot, and Peclet numbers-to characterize the competition between heat transfer within the particle, heat transfer at the particle rim, and capillary motion, for particles of different sizes. We apply this framework to the lightning case and constrain a maximum size for ash particles susceptible to surface tension-driven rounding, as a function of lightning temperature and duration, and ash properties. The size limit agrees well with maximum sizes of glass spheres found in volcanic ash that has been subjected to lightning or experimental discharges, demonstrating that the approach that we develop can be used to obtain a first-order estimate of lightning conditions in volcanic plumes.

  16. Transmission line model for strained quantum well lasers including carrier transport and carrier heating effects.

    Science.gov (United States)

    Xia, Mingjun; Ghafouri-Shiraz, H

    2016-03-01

    This paper reports a new model for strained quantum well lasers, which are based on the quantum well transmission line modeling method where effects of both carrier transport and carrier heating have been included. We have applied this new model and studied the effect of carrier transport on the output waveform of a strained quantum well laser both in time and frequency domains. It has been found that the carrier transport increases the turn-on, turn-off delay times and damping of the quantum well laser transient response. Also, analysis in the frequency domain indicates that the carrier transport causes the output spectrum of the quantum well laser in steady state to exhibit a redshift which has a narrower bandwidth and lower magnitude. The simulation results of turning-on transients obtained by the proposed model are compared with those obtained by the rate equation laser model. The new model has also been used to study the effects of pump current spikes on the laser output waveforms properties, and it was found that the presence of current spikes causes (i) wavelength blueshift, (ii) larger bandwidth, and (iii) reduces the magnitude and decreases the side-lobe suppression ratio of the laser output spectrum. Analysis in both frequency and time domains confirms that the new proposed model can accurately predict the temporal and spectral behaviors of strained quantum well lasers.

  17. Evaluation of heat treatment schedules for emerald ash borer (Coleoptera: Buprestidae).

    Science.gov (United States)

    Myers, Scott W; Fraser, Ivich; Mastro, Victor C

    2009-12-01

    The thermotolerance of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), was evaluated by subjecting larvae and prepupae to a number of time-temperature regimes. Three independent experiments were conducted during 2006 and 2007 by heating emerald ash borer infested firewood in laboratory ovens. Heat treatments were established based on the internal wood temperature. Treatments ranged from 45 to 65 degrees C for 30 and 60 min, and the ability of larvae to pupate and emerge as adults was used to evaluate the success of each treatment. A fourth experiment was conducted to examine heat treatments on exposed prepupae removed from logs and subjected to ambient temperatures of 50, 55, and 60 degrees C for 15, 30, 45, and 60 min. Results from the firewood experiments were consistent in the first experiment. Emergence data showed emerald ash borer larvae were capable of surviving a temperatures-time combination up to 60 degrees C for 30 min in wood. The 65 degrees C for 30 min treatment was, however, effective in preventing emerald ash borer emergence on both dates. Conversely, in the second experiment using saturated steam heat, complete mortality was achieved at 50 and 55 degrees C for both 30 and 60 min. Results from the prepupae experiment showed emerald ash borer survivorship in temperature-time combinations up to 55 degrees C for 30 min, and at 50 degrees C for 60 min; 60 degrees C for 15 min and longer was effective in preventing pupation in exposed prepupae. Overall results suggest that emerald ash borer survival is variable depending on heating conditions, and an internal wood temperature of 60 degrees C for 60 min should be considered the minimum for safe treatment for firewood.

  18. Seed germination of montane forest species in response to ash, smoke and heat shock in Mexico

    Science.gov (United States)

    Zuloaga-Aguilar, Susana; Briones, Oscar; Orozco-Segovia, Alma

    2011-05-01

    In many fire-prone ecosystems, seed germination is triggered by heat shock, smoke, ash and charred wood. However, few studies concerning the effect of these fire products on the germination of tropical and subtropical species exist. We assessed the effect of fire products and their interactions on seed germination in 12 species that frequently grow in burned areas of pine-oak and mixed forest in a mountainous subtropical area. Each species was exposed to a predetermined treatment of heat shock, which was optimised in accordance with a previous study. For smoke treatments, seeds were immersed in smoke water, whereas for ash treatments, 1.5 g of ash was added to the incubation medium. Germination increased in 92% of the species in response to the products of fire. Both the smoke water and the ash treatments promoted germination in four species that had permeable seed covers and physiological dormancy. Six species with physical dormancy required both heat shock and smoke water or ash to break dormancy. Our results indicate that seed germination response to fire products depends on the species and/or dormancy type. The germination response to the fire products varied between species; therefore, fire products may influence the species composition in post-fire regeneration.

  19. Carrier heating in disordered conjugated polymers in electric field

    Energy Technology Data Exchange (ETDEWEB)

    Vukmirovic, Nenad; Wang, Lin-Wang

    2010-01-26

    The electric field dependence of charge carrier transport and the effect of carrier heating in disordered conjugated polymers were investigated. A parameter-free multiscale methodology consisting of classical molecular dynamics simulation for the generation of the atomic structure, large system electronic structure and electron-phonon coupling constants calculations and the procedure for extracting the bulk polymer mobility, was used. The results suggested that the mobility of a fully disordered poly(3-hexylthiophene) (P3HT) polymer increases with electric field which is consistent with the experimental results on samples of regiorandom P3HT and different from the results on more ordered regioregular P3HT polymers, where the opposite trend is often observed at low electric fields. We calculated the electric field dependence of the effective carrier temperature and showed however that the effective temperature cannot be used to replace the joint effect of temperature and electric field, in contrast to previous theoretical results from phenomenological models. Such a difference was traced to originate from the use of simplified Miller-Abrahams hopping rates in phenomenological models in contrast to our considerations that explicitly take into account the electronic state wave functions and the interaction with all phonon modes.

  20. Optimization of activator solution and heat treatment of ground lignite type fly ash geopolymers

    Science.gov (United States)

    Molnár, Z.; Szabó, R.; Rácz, Á.; Lakatos, J.; Debreczeni, Á.; Mucsi, G.

    2017-02-01

    Geopolymers are inorganic polymers which can be produced by the reaction between silico aluminate oxides and alkali silicates in alkaline medium. Materialscontaining silica and alumina compounds are suitable for geopolymer production. These can beprimary materials or industrial wastes, i. e. fly ash, metallurgical slag and red mud. In this paper, the results of the systematic experimental series are presented which were carried out in order to optimize the geopolymer preparation process. Fly ash was ground for different residence time (0, 5, 10, 30, 60 min) in order to investigate the optimal specific surface area. NaOH activator solution concentration also varied (6, 8, 10, 12, 14 M). Furthermore, sodium silicate was added to NaOH as a network builder solution. In this last serie different heat curing temperatures (30, 60, 90°C) were also applied. After seven days of ageing the physical properties of the geopolymer(compressive strength and specimen density)were measured. Chemical leaching tests on the rawmaterial and the geopolymers were carried out to determine the elements which can be mobilized by different leaching solutions. It was found that the above mentioned parameters (fly ash fineness, molar concentration and composition of activator solution, heat curing) has great effect on the physical and chemical properties of geopolymer specimens. Optimal conditions were as follows: specific surface area of the fly ash above 2000 cm2/g, 10 M NaOH, 30°C heat curing temperature which resulted in 21 MPa compressive strength geopolymer.

  1. Increased Thermal Conductivity in Metal-Organic Heat Carrier Nanofluids

    Science.gov (United States)

    Nandasiri, Manjula I.; Liu, Jian; McGrail, B. Peter; Jenks, Jeromy; Schaef, Herbert T.; Shutthanandan, Vaithiyalingam; Nie, Zimin; Martin, Paul F.; Nune, Satish K.

    2016-06-01

    Metal-organic heat carriers (MOHCs) are recently developed nanofluids containing metal-organic framework (MOF) nanoparticles dispersed in various base fluids including refrigerants (R245Fa) and methanol. Here, we report the synthesis and characterization of MOHCs containing nanoMIL-101(Cr) and graphene oxide (GO) in an effort to improve the thermo-physical properties of various base fluids. MOHC/GO nanocomposites showed enhanced surface area, porosity, and nitrogen adsorption compared with the intrinsic nanoMIL-101(Cr) and the properties depended on the amount of GO added. MIL-101(Cr)/GO in methanol exhibited a significant increase in the thermal conductivity (by approximately 50%) relative to that of the intrinsic nanoMIL-101(Cr) in methanol. The thermal conductivity of the base fluid (methanol) was increased by about 20%. The increase in the thermal conductivity of nanoMIL-101(Cr) MOHCs due to GO functionalization is explained using a classical Maxwell model.

  2. Increased Thermal Conductivity in Metal-Organic Heat Carrier Nanofluids.

    Science.gov (United States)

    Nandasiri, Manjula I; Liu, Jian; McGrail, B Peter; Jenks, Jeromy; Schaef, Herbert T; Shutthanandan, Vaithiyalingam; Nie, Zimin; Martin, Paul F; Nune, Satish K

    2016-06-15

    Metal-organic heat carriers (MOHCs) are recently developed nanofluids containing metal-organic framework (MOF) nanoparticles dispersed in various base fluids including refrigerants (R245Fa) and methanol. Here, we report the synthesis and characterization of MOHCs containing nanoMIL-101(Cr) and graphene oxide (GO) in an effort to improve the thermo-physical properties of various base fluids. MOHC/GO nanocomposites showed enhanced surface area, porosity, and nitrogen adsorption compared with the intrinsic nanoMIL-101(Cr) and the properties depended on the amount of GO added. MIL-101(Cr)/GO in methanol exhibited a significant increase in the thermal conductivity (by approximately 50%) relative to that of the intrinsic nanoMIL-101(Cr) in methanol. The thermal conductivity of the base fluid (methanol) was increased by about 20%. The increase in the thermal conductivity of nanoMIL-101(Cr) MOHCs due to GO functionalization is explained using a classical Maxwell model.

  3. Adsorption Kinetics of Reactive Dyes on Ash from Town Heating Plant

    Directory of Open Access Journals (Sweden)

    Djordjevic Dragan

    2014-12-01

    Full Text Available In order to investigate the mechanism of adsorption of reactive dyes from the textile industry on ash from heating plant produced by brown coal combustion, some characteristic sorption constants are determined using Langergren adsorption equations for pseudo-fi rst and pseudo-second order. Combined kinetic models of pseudo-first order and pseudo-second order can provide a simple but satisfactory explanation of the adsorption process for a reactive dye. According to the characteristic diagrams and results of adsorption kinetic parameters of reactive dyes on ashes, for the applied amounts of the adsorbents and different initial dye concentrations, it can be concluded that the rate of sorption is fully functionally described by second order adsorption model. According to the results, the rate constant of pseudo-second order decreases with increasing initial dye concentration and increases with increasing amount of adsorbent – ash.

  4. Preparation of Silica by Alkaline-Heating and Precipitation Method from Corn Straw Ash

    OpenAIRE

    Xudong Chen; Ming Xie; Huaibin Wang; Yingxi Xue; Zhengqi Li

    2014-01-01

    The preparation of silica by an alkaline-heating and precipitation method from corn straw ash (CSA) obtained from a biomass power plant was the focus of this study. Sodium hydroxide was used as the silica extraction reagent, and H2SO4 was the precipitator. The concentration of sodium hydroxide solution was confirmed to have a significant influence on the production of sodium silicate from CSA. The optimum technological parameters for the preparation of sodium silicate and the suitable paramet...

  5. Increased Thermal Conductivity in Metal-Organic Heat Carrier Nanofluids

    Energy Technology Data Exchange (ETDEWEB)

    Nandasiri, Manjula I.; Liu, Jian; McGrail, B. Peter; Jenks, Jeromy WJ; Schaef, Herbert T.; Shutthanandan, V.; Nie, Zimin; Martin, Paul F.; Nune, Satish K.

    2016-06-15

    Metal organic heat carriers (MOHCs) are recently developed nanofluids containing metal organic framework (MOF) nanoparticles dispersed in various base fluids including refrigerants (R245Fa) and methanol. MOHCs utilize the MOF properties to improve the thermo-physical properties of base fluids. Here, we report the synthesis and characterization of MOHCs containing nanoMIL-101(Cr) and graphene oxide (GO) in an effort to improve the thermo-physical properties of various base fluids. MOHC containing MIL-101(Cr)/GO nanocomposites showed enhanced surface area, porosity, and nitrogen adsorption compared with the intrinsic nano MIL-101(Cr) and the properties depend on the amount of GO added. Powder X-ray diffraction (PXRD) confirmed the preserved crystallinity of MIL-101(Cr) in all nanocomposites with the absence of any unreacted GO. Scanning electron microscopy images confirmed the presence of near spherical MIL-101(Cr) nanoparticles in the range of 40-80 nm in diameter. MOHC nanofluids containing MIL-101(Cr)/GO in methanol exhibited significant enhancement in the thermal conductivity (by approxi-mately 50%) relative to that of the intrinsic nano MIL-101(Cr) in methanol. The thermal conductivity of base fluid (methanol) was enhanced by about 20 %. The enhancement in the thermal conductivity of nanoMIL-101(Cr) MOHCs due to graphene oxide functionalization is explained using a classical Maxwell model.

  6. Simulation methods of rocket fuel refrigerating with liquid nitrogen and intermediate heat carrier

    Directory of Open Access Journals (Sweden)

    O. E. Denisov

    2014-01-01

    Full Text Available Temperature preparation of liquid propellant components (LPC before fueling the tanks of rocket and space technology is the one of the operations performed by ground technological complexes on cosmodromes. Refrigeration of high-boiling LPC is needed to increase its density and to create cold reserve for compensation of heat flows existing during fueling and prelaunch operations of space rockets.The method and results of simulation of LPC refrigeration in the recuperative heat exchangers with heat carrier which is refrigerated by-turn with liquid nitrogen sparging. The refrigerating system consists of two tanks (for the chilled coolant and LPC, LPC and heat carrier circulation loops with heat exchanger and system of heat carrier refrigeration in its tank with bubbler. Application of intermediate heat carrier between LPC and liquid nitrogen allows to avoid LPC crystallization on cold surfaces of the heat exchanger.Simulation of such systems performance is necessary to determine its basic design and functional parameters ensuring effective refrigerating of liquid propellant components, time and the amount of liquid nitrogen spent on refrigeration operation. Creating a simulator is quite complicated because of the need to take into consideration many different heat exchange processes occurring in the system. Also, to determine the influence of various parameters on occurring processes it is necessary to take into consideration the dependence of all heat exchange parameters on each other: heat emission coefficients, heat transfer coefficients, heat flow amounts, etc.The paper offers an overview of 10 references to foreign and Russian publications on separate issues and processes occurring in liquids refrigerating, including LPC refrigeration with liquid nitrogen. Concluded the need to define the LPC refrigerating conditions to minimize cost of liquid nitrogen. The experimental data presented in these publications is conformed with the application of

  7. Study on the structural change and heat transfer characteristics of ash deposit layers in the coal gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Kazuyoshi Ichikawa; Yuso Oki; Jun Inumaru [Central Research Institute of Electric Power Industry (CREIPI) (Japan)

    2005-07-01

    Ash deposition is often observed in the coal gasifier. As it may interfere the operation of gasifier, in case of excessive deposition, a study is needed to evaluate the ash deposition characteristics on the gasifier wall, its ability to grow after deposition, and influence of the formation of deposition layers on the heat transfer capability in advance. CRIEPI has conducted a study of the basic gasification process and operational technology using a 2T/D air-blown pressurized entrained-flow coal gasifier (2 T/D gasifier) since 1983. In a previous work, the authors calculated the ash liquid phase ratio as an index of the ash melting characteristics in correspondence to continuous temperature change, and established the relationship with the ash deposition characteristics. We also proposed as the technique to predict ash deposition characteristics in the gasifier by construction of a model based upon the correlation and introduction into the numerical analysis code. In this report, the relationship between the sintering structure and the heat transfer characteristics of deposition layer is studied. The heat transfer mechanism in the layer was also pursued. 7 refs., 6 figs., 1 tab.

  8. Hydration Characteristics of Low-Heat Cement Substituted by Fly Ash and Limestone Powder

    Directory of Open Access Journals (Sweden)

    Si-Jun Kim

    2015-09-01

    Full Text Available This study proposed a new binder as an alternative to conventional cement to reduce the heat of hydration in mass concrete elements. As a main cementitious material, low-heat cement (LHC was considered, and then fly ash (FA, modified FA (MFA by vibrator mill, and limestone powder (LP were used as a partial replacement of LHC. The addition of FA delayed the induction period at the hydration heat curve and the maximum heat flow value (qmax increased compared with the LHC based binder. As the proportion and fineness of the FA increased, the induction period of the hydration heat curve was extended, and the qmax increased. The hydration production of Ca(OH2 was independent of the addition of FA or MFA up to an age of 7 days, beyond which the amount of Ca(OH2 gradually decreased owing to their pozzolanic reaction. In the case of LP being used as a supplementary cementitious material, the induction period of the hydration heat curve was reduced by comparison with the case of LHC based binder, and monocarboaluminate was observed as a hydration product. The average pore size measured at an age of 28 days was smaller for LHC with FA or MFA than for 100% LHC.

  9. Experimental investigation of ash deposits on convection heating surfaces of a circulating fluidized bed municipal solid waste incinerator.

    Science.gov (United States)

    Tang, Zhi; Chen, Xiaoping; Liu, Daoyin; Zhuang, Yaming; Ye, Minghua; Sheng, Hongchan; Xu, Shaojuan

    2016-10-01

    Incineration of municipal solid waste (MSW) is a waste treatment method which can be sustainable in terms of waste volume reduction, as well as a source of renewable energy. During MSW combustion, increased formation of deposits on convection heating exchanger surfaces can pose severe operational problems, such as fouling, slagging and corrosion. These problems can cause lower heat transfer efficiency from the hot flue gas to the working fluid inside the tubes. A study was performed where experiments were carried out to examine the ash deposition characteristics in a full-scale MSW circulating fluidized bed (CFB) incinerator, using a newly designed deposit probe that was fitted with six thermocouples and four removable half rings. The influence of probe exposure time and probe surface temperature (500, 560, and 700°C) on ash deposit formation rate was investigated. The results indicate that the deposition mass and collection efficiency achieve a minimum at the probe surface temperature of 560°C. Ash particles are deposited on both the windward and leeward sides of the probe by impacting and thermophoretic/condensation behavior. The major inorganic elements present in the ash deposits are Ca, Al and Si. Compared to ash deposits formed on the leeward side of the probe, windward-side ash deposits contain relatively higher Ca and S concentrations, but lower levels of Al and Si. Among all cases at different surface temperatures, the differences in elemental composition of the ash deposits from the leeward side are insignificant. However, as the surface temperature increases, the concentrations of Al, Si, K and Na in the windward-side ash deposits increase, but the Ca concentration is reduced. Finally, governing mechanisms are proposed on the basis of the experimental data, such as deposit morphology, elemental composition and thermodynamic calculations.

  10. Effect of Concentration of Sodium Hydroxide and Degree of Heat Curing on Fly Ash-Based Geopolymer Mortar

    Directory of Open Access Journals (Sweden)

    Subhash V. Patankar

    2014-01-01

    Full Text Available Geopolymer concrete/mortar is the new development in the field of building constructions in which cement is totally replaced by pozzolanic material like fly ash and activated by alkaline solution. This paper presented the effect of concentration of sodium hydroxide, temperature, and duration of oven heating on compressive strength of fly ash-based geopolymer mortar. Sodium silicate solution containing Na2O of 16.45%, SiO2 of 34.35%, and H2O of 49.20% and sodium hydroxide solution of 2.91, 5.60, 8.10, 11.01, 13.11, and 15.08. Moles concentrations were used as alkaline activators. Geopolymer mortar mixes were prepared by considering solution-to-fly ash ratio of 0.35, 0.40, and 0.45. The temperature of oven curing was maintained at 40, 60, 90, and 120°C each for a heating period of 24 hours and tested for compressive strength at the age of 3 days as test period after specified degree of heating. Test results show that the workability and compressive strength both increase with increase in concentration of sodium hydroxide solution for all solution-to-fly ash ratios. Degree of heating also plays vital role in accelerating the strength; however there is no large change in compressive strength beyond test period of three days after specified period of oven heating.

  11. Measurement of the Specific Heat of Plastic Waste/Fly Ash Composite Material Using Differential Scanning Calorimetry

    Science.gov (United States)

    Fujino, J.; Honda, T.

    2009-06-01

    Plastic waste/fly ash composite, which is made mostly from plastic waste and fly ash, is one of the materials developed for the purpose of recycling. Currently, the composite is used for cable troughs shielding underground lines. However, there exists little information concerning the thermophysical properties of the composite. Thermophysical properties and the structure of the composite must be determined to estimate the heat transfer in the composite and create the different proportions of the composite material. This article deals with measurements of the specific heat of the plastic waste/fly ash composite and its components using a differential scanning calorimeter. The composite sample, which ranged from 10 mg to 19 mg in mass, was cut from a cable trough. The standard reference material is synthetic sapphire disks of 19.6 mg and 29.6 mg in mass. The specific heat of the plastic waste/fly ash composite increases from 1.25 kJ · kg-1 · K-1 to 1.59 kJ · kg-1 · K-1 at temperatures from 305 K to 360 K. The uncertainty for the specific heat data of the composite is estimated to be about 4 %. In addition, the specific heat value depends heavily on the content of the plastic waste.

  12. Fuel, fire and heat: an experimental approach to highlight the potential of studying ash and char remains from archaelological contexts

    NARCIS (Netherlands)

    Braadbaart, F.; Poole, I.; Huisman, H.D.J.; Os, B. van

    2012-01-01

    As in traditional societies today ancient societies probably selected different fuels to meet specific heat requirements. Char and ash, the end products of fire, are often found in abundance in archaeological contexts. These end products can provide information regarding (i) the original fuel resour

  13. Studying the melting behavior of coal, biomass, and coal/biomass ash using viscosity and heated stage XRD data

    DEFF Research Database (Denmark)

    Arvelakis, Stelios; Folkedahl, B.; Dam-Johansen, Kim

    2006-01-01

    unscheduled shutdowns, decreasing the availability and increasing the cost of the produced power. In addition, the fouling of the heat exchange surfaces reduces the system efficiency. In this work the melting and rheological properties of various biomass and biomass/ coal ash samples were studied by using......The use of biomass for power generation can result in significant economical and environmental benefits. The greenhouse emissions can be reduced as well as the cost of the produced electricity. However, ash-related problems, including slagging, agglomeration, and corrosion, can cause frequent...

  14. ICSC Problems and Perspectives of high-calcium fly ash from heat power plants in the composition of “green” building materials

    Directory of Open Access Journals (Sweden)

    Domanskaya Irina

    2016-01-01

    Full Text Available The peculiarities of the composition formation and hydraulic activity of high calcium fly ash got by burning of Kansk-Achinsk brown coals have been described. Fly ashes selected in dry state can be used as peculiar (specific binding agents (minerals on condition of their preliminary handling reducing nonuniform volume change of the ash stone during hydration and also the expansion range of their application in green building. The cavitation technologies, the organization of the fly ash granulation at heat power plants instead of hydraulic ash removal systems and enrichment by various means to extract rare-earth metals are considered to be the most perspective methods of fly ash conditioning.

  15. Assessment of the heat carrier movement in the primary coolant circuit by its own momentum

    Energy Technology Data Exchange (ETDEWEB)

    Kadalev, Stoyan, E-mail: kadalev@inrne.bas.bg

    2014-10-15

    Highlights: • We model the heat carrier flow alteration after the circulation pump(s) stop. • The general mathematical model used is described in details. • The model is adapted and applied to a particular example research reactor. • Assessment is presented in detail, step by step with references. • The information provided is enough to apply calculations to another facility. - Abstract: In the presented paper is considered the approach to an assessment of the heat carrier flow alteration in the primary water–water reactor coolant circuit after the circulation pump(s) stop. This topic is highly relevant trough advanced and increased nuclear safety requirements because such a process is observed in case of black-out accident or damaged pump(s). The general mathematical model used is described; enabling preparation of this evaluation adapted and applied to a particular example facility namely a pool type research reactor. The factors influencing to the heat carrier movement by its own momentum are examined. The evaluation measures and includes the factors influencing the heat carrier flow rate from the moment the pump(s) stops down to a negligible value. Assessment is presented in detail, step by step and where needed with references to specific data and/or formulae from reference books to allow repetition of the calculations and/or apply to another facility. The calculations are presented utilizing all necessary data according to the design and technological documentation. No account is given to the pressure of the natural circulation caused by the residual heat generation in the fuel after the reactor scram system extinction of the fission reaction.

  16. Nodal quasi-particles of the high-Tc superconductors as carriers of heat

    Directory of Open Access Journals (Sweden)

    K. Behnia

    2006-09-01

    Full Text Available   In the quest for understanding correlated electrons, high-temperature superconductivity remains a formidable challenge and a source of insight. This paper briefly recalls the central achievement by the study of heat transport at low temperatures. At very low temperatures, nodal quasi-particles of the d-wave superconducting gap become the main carriers of heat. Their thermal conductivity is unaffected by disorder and reflects the fine structure of the superconducting gap. This finding had led to new openings in the exploration of other unconventional superconductors

  17. Studying the melting behavior of coal, biomass, and coal/biomass ash using viscosity and heated stage XRD data

    DEFF Research Database (Denmark)

    Arvelakis, Stelios; Folkedahl, B.; Dam-Johansen, Kim

    2006-01-01

    a high-temperature rotational viscometer and a hot stage XRD. The produced data were used to calculate the operating temperature of a pilot-scale entrained flow reactor during the cocombustion of biomass/ coal samples in order to ensure the slag flow and to avoid corrosion of the walls due to liquid slag......The use of biomass for power generation can result in significant economical and environmental benefits. The greenhouse emissions can be reduced as well as the cost of the produced electricity. However, ash-related problems, including slagging, agglomeration, and corrosion, can cause frequent...... unscheduled shutdowns, decreasing the availability and increasing the cost of the produced power. In addition, the fouling of the heat exchange surfaces reduces the system efficiency. In this work the melting and rheological properties of various biomass and biomass/ coal ash samples were studied by using...

  18. Processing of ash and slag waste of heating plants by arc plasma to produce construction materials and nanomodifiers

    Science.gov (United States)

    Buyantuev, S. L.; Urkhanova, L. A.; Kondratenko, A. S.; Shishulkin, S. Yu; Lkhasaranov, S. A.; Khmelev, A. B.

    2017-01-01

    The resultsare presented of plasma processing slag and ash waste from coal combustion in heating plants. Melting mechanism of ashand slagraw material is considered by an electromagnetic technological reactor. The analysis was conducted of temperature and phase transformations of raw material when it is heated up to the melting point, and also determination of specific energy consumption by using a generalized model of the thermodynamic analysis of TERRA. The study of materials melting temperature conditions and plum of melt was carried with high-temperature thermal imaging method, followed by mapping and 3D-modeling of the temperature fields. The investigations to establish the principal possibilities of using slag waste of local coal as raw material for the production of mineral (ash and slag) fibers found that by chemical composition there are oxides in the following ranges: 45-65% SiO2; 10-25% Al2O3; 10-45% CaO; 5-10% MgO; other minerals (less than 5%). Thus, these technological wastes are principally suitable for melts to produce mineral wool by the plasma method. An analysis of the results shows the melting point of ash and slag waste - 1800-2000 °C. In this case the specific energy consumption of these processes keeps within the limits of 1.1-1.3 kW*h/kg. For comparison it should be noted that the unit cost of electricity in the known high-melting industrial installations 5-6 kW*h/kg. Upon melting ash and slag waste, which contains up to 2-5% of unburned carbon, carbon nanomaterials were discovered.in the form of ultrafine soot accumulating as a plaque on the water-cooled surfaces in the gas cleaning chamber. The process of formation of soot consists in sublimation-desublimation of part of carbon which is in ash and slag, and graphite electrode. Thus, upon melting of ash and slag in the electromagnetic reactor it is possible to obtain melt, and in the subsequent mineral high quality fiber, which satisfies the requirements of normative documents, and

  19. Enhanced biomedical heat-triggered carriers via nanomagnetism tuning in ferrite-based nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Angelakeris, M., E-mail: agelaker@auth.gr [Department of Physics, Aristotle University of Thessaloniki, 54124 Greece (Greece); Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, Lotharstr. 1, Duisburg D-47048 (Germany); Li, Zi-An; Hilgendorff, M. [Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, Lotharstr. 1, Duisburg D-47048 (Germany); Simeonidis, K.; Sakellari, D. [Department of Physics, Aristotle University of Thessaloniki, 54124 Greece (Greece); Filippousi, M.; Tian, H.; Van Tendeloo, G. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Spasova, M.; Acet, M.; Farle, M. [Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, Lotharstr. 1, Duisburg D-47048 (Germany)

    2015-05-01

    Biomedical nanomagnetic carriers are getting a higher impact in therapy and diagnosis schemes while their constraints and prerequisites are more and more successfully confronted. Such particles should possess a well-defined size with minimum agglomeration and they should be synthesized in a facile and reproducible high-yield way together with a controllable response to an applied static or dynamic field tailored for the specific application. Here, we attempt to enhance the heating efficiency in magnetic particle hyperthermia treatment through the proper adjustment of the core–shell morphology in ferrite particles, by controlling exchange and dipolar magnetic interactions at the nanoscale. Thus, core–shell nanoparticles with mutual coupling of magnetically hard (CoFe{sub 2}O{sub 4}) and soft (MnFe{sub 2}O{sub 4}) components are synthesized with facile synthetic controls resulting in uniform size and shell thickness as evidenced by high resolution transmission electron microscopy imaging, excellent crystallinity and size monodispersity. Such a magnetic coupling enables the fine tuning of magnetic anisotropy and magnetic interactions without sparing the good structural, chemical and colloidal stability. Consequently, the magnetic heating efficiency of CoFe{sub 2}O{sub 4} and MnFe{sub 2}O{sub 4} core–shell nanoparticles is distinctively different from that of their counterparts, even though all these nanocrystals were synthesized under similar conditions. For better understanding of the AC magnetic hyperthermia response and its correlation with magnetic-origin features we study the effect of the volume ratio of magnetic hard and soft phases in the bimagnetic core−shell nanocrystals. Eventually, such particles may be considered as novel heating carriers that under further biomedical functionalization may become adaptable multifunctional heat-triggered nanoplatforms. - Highlights: • Core–shell ferrite magnetic nanoparticles as magnetic particle hyperthermia

  20. More Wind Power Integration with Adjusted Energy Carriers for Space Heating in Northern China

    Directory of Open Access Journals (Sweden)

    Jianjun He

    2012-08-01

    Full Text Available In Northern China, due to the high penetration of coal-fired cogeneration facilities, which are generally equipped with extraction-condensing steam turbines, lots of wind power resources may be wasted during the heating season. In contrast, considerable coal is consumed in the power generation sector. In this article, firstly it is revealed that there exists a serious divergence in the ratio of electrical to thermal energy between end users’ demand and the cogenerations’ production during off-peak load at night, which may negate active power-balancing of the electric power grid. Secondly, with respect to this divergence only occurring during off-peak load at night, a temporary proposal is given so as to enable the integration of more wind power. The authors suggest that if the energy carrier for part of the end users’ space heating is switched from heating water to electricity (e.g., electric heat pumps (EHPs can provide space heating in the domestic sector, the ratio of electricity to heating water load should be adjusted to optimize the power dispatch between cogeneration units and wind turbines, resulting in fuel conservation. With this proposal, existing infrastructures are made full use of, and no additional ones are required. Finally a numerical simulation is performed in order to illustrate both the technical and economic feasibility of the aforementioned proposal, under ongoing infrastructures as well as electricity and space heating tariff conditions without changing participants’ benefits. The authors aim to persuade Chinese policy makers to enable EHPs to provide space heating to enable the integration of more wind power.

  1. Heat treatment of Firewood for Emerald Ash Borer (Agrilus planipennis Fairmaire): Case Studies

    Science.gov (United States)

    Xiping Wang; Richard D. Bergman; Brian K. Brashaw; Scott W. Myers

    2014-01-01

    The movement of firewood within emerald ash borer (Agrilus planipennis Fairmaire) (EAB)-infested states and into adjoining areas has been a contributor to its spread throughout the United States and Canada. In an effort to prevent further human-aided spread of EAB and to facilitate interstate commerce, the USDA Animal and Plant Health Inspection Service and cooperating...

  2. 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.

  3. Development of a waste heat recovery system onboard LNG carrier to meet IMO regulations

    Directory of Open Access Journals (Sweden)

    Khaled Senary

    2016-09-01

    Full Text Available Problems resulting from gas emissions lead to increase the concern about safety and health issues with the demand to reduce the emissions from marine shipping. Marine power plants are considered as one of the greatest contributors in the pollutants around the world. Waste heat recovery systems when implemented with ship propulsion system can reduce emissions, fuel consumption and improve the overall efficiency of power generation and utilization. The present article describes the waste heat recovery technology and the potential for ship operators to lower the fuel costs, exhaust emissions, and the effect on the EEDI of the ship. The main research target is to improve the propulsion machinery efficiency of liquefied natural gas carrier using WHRS. The proposed system leads to meet the requirements and regulations set by the IMO for TIER III.

  4. Carrier and heat transport properties of polycrystalline GeSn films on SiO2

    Science.gov (United States)

    Uchida, Noriyuki; Maeda, Tatsuro; Lieten, Ruben R.; Okajima, Shingo; Ohishi, Yuji; Takase, Ryohei; Ishimaru, Manabu; Locquet, Jean-Pierre

    2015-12-01

    We evaluated the potential of polycrystalline (poly-) GeSn as channel material for the fabrication of thin film transistors (TFTs) at a low thermal budget (GeSn films with a grain size of ˜50 nm showed a carrier mobility of ˜30 cm2 V-1 s-1 after low-temperature annealing at 475-500 °C. Not only carrier mobility but also thermal conductivity of the films is important in assessing the self-heating effect of the poly-GeSn channel TFT. The thermal conductivity of the poly-GeSn films is 5-9 W m-1 K-1, which is significantly lower compared with 30-60 W m-1 K-1 of bulk Ge; this difference results from phonon scattering at grain boundaries and Sn interstitials. The poly-GeSn films have higher carrier mobility and thermal conductivity than poly-Ge films annealed at 600 °C, because of the improved crystal quality and coarsened grain size resulting from Sn-induced crystallization. Therefore, the poly-GeSn film is well-suited as channel material for TFTs, fabricated with a low thermal budget.

  5. A new kind of magnetic targeting induction heating drug carrier and its physical and biological properties

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Nano-carbon and iron composite―carbon-coated iron nanoparticles (CCINs) produced by carbon arc method can be used as a new kind of magnetic targeting induction heating drug carrier for cancer therapy. The structure and morphology of CCINs are studied by X-ray diffraction (XRD) and transmission electron microscope (TEM). Mossbauer spectra of these nanoparticles show that they contain only iron and carbon, without ferric carbide and ferric oxide. CCINs can be used as the magnetic drug carrier, with the effect of targeting magnetic induction heating in its inner core and higher drug adsorption in its nano-carbon shell outside because of its high specific surface area. CCINs can absorb Epirubicin (EPI) of 160 μg/mg measured by an optical spectrometer. In acute toxicity experiment with mice, the median lethal dose (LD50) of EPI is 16.9 mg/kg, while that of EPI-CCINs mixture is 20.7 mg/kg and none of the mice died after pure CCINs medication. The results show that pure CCINs belong to non-toxic grade and EPI delivery in mixture with CCINs can reduce its acute toxicity in mice. The magnetic properties of CCINs and their magnetic induction heating are investigated. The iron nanoparticle in its inner core has better magnetism with a good effect on targeting magnetic induction heating. When the CCINs are mixed with physiological salt water and are injected uniformly in pig’s liver, the temperature goes up to 48℃. While in the case that CCINs are filled in a certain section of pig’s liver, the temperature goes up to 52℃. In both cases the temperature is high enough to kill the cancer cell. CCINs have potential applications in cancer therapy.

  6. Chemical and physical properties of cyclone fly ash from the grate-fired boiler incinerating forest residues at a small municipal district heating plant (6MW).

    Science.gov (United States)

    Pöykiö, R; Rönkkömäki, H; Nurmesniemi, H; Perämäki, P; Popov, K; Välimäki, I; Tuomi, T

    2009-03-15

    In Finland, the new limit values for maximal allowable heavy metal concentrations for materials used as an earth construction agent came into force in July 2006. These limit values are applied if ash is utilized, e.g. in roads, cycling paths, pavements, car parks, sport fields, etc. In this study we have determined the most important chemical and physical properties of the cyclone fly ash originating from the grate-fired boiler incinerating forest residues (i.e. wood chips, sawdust and bark) at a small municipal district heating plant (6 MW), Northern Finland. This study clearly shows that elements are enriched in cyclone fly ash, since the total element concentrations in the cyclone fly ash were within 0.2-10 times higher than those in the bottom ash. The total concentrations of Cd (25 mg kg(-1); d.w.), Zn (3630 mg kg(-1); d.w.), Ba (4260 mg kg(-1); d.w.) and Hg (1.7 mg kg(-1); d.w.) exceeded the limit values, and therefore the cyclone fly ash cannot be used as an earth construction agent. According to the leached amounts of Cr (38 mg kg(-1); d.w.), Zn (51 mg kg(-1); d.w.) and sulphate (50,000 mg kg(-1); d.w.), the cyclone fly ash is classified as a hazardous waste, and it has to be deposited in a hazardous waste landfill.

  7. Research of Heat Transfer Model in Rotary Ash Coolers%滚筒冷渣器传热模型的研究

    Institute of Scientific and Technical Information of China (English)

    司小东; 吕俊复; 王巍; 李金晶

    2011-01-01

    分析了携带翅片滚筒冷渣器内灰渣颗粒的流动过程和传热过程,提出了滚筒冷渣器一维轴向传热模型,模型中考虑了渣中未燃尽碳的残余燃烧,模型参数根据文献和实验室实验确定.利用该模型对一台300MW循环流化床锅炉上滚筒冷渣器的温度进行了预测,并与实际运行参数进行了比较.结果表明:该模型可以很好地预测滚筒冷渣器出口灰渣的温度和冷却水温度.%By analyzing the flow and heat transfer process of ash particles in a rotary ash cooler with fins, a one-dimensional heat transfer model was proposed, in which the reburning of residual carbon in bottom ash was considered while the model parameters determined in accordance with relevant reference materials and experimental results. Using the model, temperatures of rotary ash cooler for a 300 MW circulating fluidized bed boiler were predicted, which were then compared with actual operation parameters. Comparison results prove the model to be accurate in predicting ash discharge and cooling water temperatures of rotary ash coolers.

  8. Spectral hole-burning and carrier-heating dynamics in InGaAs quantum-dot amplifiers

    DEFF Research Database (Denmark)

    Borri, Paola; Langbein, Wolfgang Werner; Hvam, Jørn Märcher

    2000-01-01

    The ultrafast gain and index dynamics in a set of InAs-InGaAs-GaAs quantum-dot (QD) amplifiers are measured at room temperature with femtosecond resolution. The role of spectral hole-burning (SHB) and carrier heating (CH) in the recovery of gain compression is investigated in detail. An ultrafast...... recovery of the spectral hole within ~100 fs is measured, comparable to bulk and quantum-well amplifiers, which is contradicting a carrier relaxation bottleneck in electrically pumped QD devices. The CH dynamics in the QD is quantitatively compared with results on an InGaAsP bulk amplifier. Reduced CH...... for both gain and refractive index dynamics of the QD devices is found, which is a promising prerequisite for high-speed applications. This reduction is attributed to reduced free-carrier absorption-induced heating caused by the small carrier density necessary to provide amplification in these low...

  9. Thermal Fluid Analysis of the Heat Sink and Chip Carrier Assembly for a US Army Research Laboratory Liquid-Fueled Thermophotovoltaic Power Source Demonstrator

    Science.gov (United States)

    2016-09-01

    ARL-TR-7829 ● SEP 2016 US Army Research Laboratory Thermal Fluid Analysis of the Heat Sink and Chip Carrier Assembly for a US...ARL-TR-7829 ● SEP 2016 US Army Research Laboratory Thermal Fluid Analysis of the Heat Sink and Chip Carrier Assembly for a US...4. TITLE AND SUBTITLE Thermal Fluid Analysis of the Heat Sink and Chip Carrier Assembly for a US Army Research Laboratory Liquid-Fueled

  10. Printed Circuit Boards with Integrated Heat Carrier Channels for Deep Geothermal Resources

    Science.gov (United States)

    Krühn, T.; Overmeyer, L.

    2012-04-01

    The exploration of deep geothermal resources is still very expensive. A large amount of these costs is caused by the drilling process. The high price results from a high failure risk, slow drilling progress and a large amount of manual work. To develop deep heat mining to a sizeable contribution to the European energy portfolio, the exploration process has to become a lot cheaper. One step to achieve lower costs is to monitor and automate the drilling process. Therefore, electronic components such as sensors and data processing units must be integrated into the Bottom Hole Assembly (BHA). The integration of electronics into the BHA faces the challenge of high ambient temperatures. The project "Packaging of Electronic Components for High Temperature Applications" within the "Geothermal Energy and High Performance-Drilling Collaborative Research Program (gebo)" develops a system of heat carrier channels integrated in printed circuit boards (PCB). These channels can be perfused with fluids such as water, oil or gas and provide high heat convection rates. Such PCBs will be able to withstand high ambient temperatures up to 250 °C. We have simulated, manufactured and are currently testing prototype boards with integrated heat carrier channels featuring a thickness of only 1.6 mm. As a simulation scenario, we chose a board measuring 25 mm x 100 mm, dimensions suitable for integration into a BHA. An ambient temperature of 250 °C was used. The simulation results presented in this contribution illustrate that cooling of the whole board as well as cooling of hotspots is possible. The cooling channel layout being the key for high convection rates was meticulously studied and optimized. Parameters such as necessary flow rate and fluid pressure were adjusted accordingly. Preliminary experiments validate the demonstrated and discussed simulation results. With the proposed cooling system, it is possible to integrate microelectronic components into the BHA for drilling

  11. Analysis of heat conduction in a drum brake system of the wheeled armored personnel carriers

    Science.gov (United States)

    Puncioiu, A. M.; Truta, M.; Vedinas, I.; Marinescu, M.; Vinturis, V.

    2015-11-01

    This paper is an integrated study performed over the Braking System of the Wheeled Armored Personnel Carriers. It mainly aims to analyze the heat transfer process which is present in almost any industrial and natural process. The vehicle drum brake systems can generate extremely high temperatures under high but short duration braking loads or under relatively light but continuous braking. For the proper conduct of the special vehicles mission in rough terrain, we are talking about, on one hand, the importance of the possibility of immobilization and retaining position and, on the other hand, during the braking process, the importance movement stability and reversibility or reversibility, to an encounter with an obstacle. Heat transfer processes influence the performance of the braking system. In the braking phase, kinetic energy transforms into thermal energy resulting in intense heating and high temperature states of analyzed vehicle wheels. In the present work a finite element model for the temperature distribution in a brake drum is developed, by employing commercial finite element software, ANSYS. These structural and thermal FEA models will simulate entire braking event. The heat generated during braking causes distortion which modifies thermoelastic contact pressure distribution drum-shoe interface. In order to capture the effect of heat, a transient thermal analysis is performed in order to predict the temperature distribution transitional brake components. Drum brakes are checked both mechanical and thermal. These tests aim to establish their sustainability in terms of wear and the variation coefficient of friction between the friction surfaces with increasing temperature. Modeling using simulation programs led eventually to the establishment of actual thermal load of the mechanism of brake components. It was drawn the efficiency characteristic by plotting the coefficient of effectiveness relative to the coefficient of friction shoe-drum. Thus induced

  12. 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

  13. Application of Heat Pipe Technology in Flue Gas Waste Heat Recycling of Organic Heat Carrier Boiler%热管技术在有机热载体锅炉烟气余热回收上的应用

    Institute of Scientific and Technical Information of China (English)

    黄云燕

    2014-01-01

    In recent years, more and more construction units use heat pipe technology to reduce exhaust gas temperature for reducing flue gas heat loss. Industrial managers should attach great importance to the application of heat pipe technology in the flue gas waste heat recycling of organic heat carrier boiler. From energy consumption situation of organic heat carrier boiler, this paper introduces the main purpose of flue gas waste heat recycling of organic heat carrier boiler, carries on a brief introduction for application of heat pipe technology in flue gas waste heat recycling of organic heat carrier boiler.%近些年来,越来越多建设单位采用热管技术降低排烟温度来减少烟气热损失,工业管理者应该高度重视热管技术在有机热载体锅炉烟气余热回收上的应用。本文从有机热载体锅炉能耗状况着手,介绍了有机热载体锅炉烟气余热回收的主要用途,对热管技术在有机热载体锅炉烟气余热回收上的应用做了简单介绍。

  14. MECHANICAL CHARACTERIZATION OF HEAT-TREATED ASH WOOD IN RELATION WITH STRUCTURAL TIMBER STANDARDS

    Directory of Open Access Journals (Sweden)

    Simon HANNOUZ

    2015-06-01

    Full Text Available Heat treatment is an attractive method to enhance wood durability, and valorize local hardwood species with natural low durability. Yet no standard allows the certification of such products. This study first aims to observe the influence of heat treatment on the different mechanical properties. The standard mechanical tests; bending, tension parallel and perpendicular to grain, compression parallel and perpendicular to grain and shear, have been performed on native and heat-treated woods samples. The measurements are then compared to values of EN 338 standard. Results reveal that shear strength is the property most affected by heat treatment and that the modulus of elasticity perpendicular to grain is increased. The values given by EN 338 standard are generally safe with the exception of shear strength which is underestimated by current relationships. It is suggested that new relationships have to be provided for heat-treated wood, taking into account the loss of shear resistance.

  15. A fast Eulerian multiphase flow model for volcanic ash plumes: turbulence, heat transfer and particle non-equilibrium dynamics.

    Science.gov (United States)

    Cerminara, Matteo; Esposti Ongaro, Tomaso; Carlo Berselli, Luigi

    2014-05-01

    We have developed a compressible multiphase flow model to simulate the three-dimensional dynamics of turbulent volcanic ash plumes. The model describes the eruptive mixture as a polydisperse fluid, composed of different types of gases and particles, treated as interpenetrating Eulerian phases. Solid phases represent the discrete ash classes into which the total granulometric spectrum is discretized, and can differ by size and density. The model is designed to quickly and accurately resolve important physical phenomena in the dynamics of volcanic ash plumes. In particular, it can simulate turbulent mixing (driving atmospheric entrainment and controlling the heat transfer), thermal expansion (controlling the plume buoyancy), the interaction between solid particles and volcanic gas (including kinetic non-equilibrium effects) and the effects of compressibility (over-pressured eruptions and infrasonic measurements). The model is based on the turbulent dispersed multiphase flow theory for dilute flows (volume concentration <0.001, implying that averaged inter-particle distance is larger than 10 diameters) where particle collisions are neglected. Moreover, in order to speed up the code without losing accuracy, we make the hypothesis of fine particles (Stokes number <0.2 , i.e., volcanic ash particles finer then a millimeter), so that we are able to consider non-equilibrium effects only at the first order. We adopt LES formalism (which is preferable in transient regimes) for compressible flows to model the non-linear coupling between turbulent scales and the effect of sub-grid turbulence on the large-scale dynamics. A three-dimensional numerical code has been developed basing on the OpenFOAM computational framework, a CFD open source parallel software package. Numerical benchmarks demonstrate that the model is able to capture important non-equilibrium phenomena in gas-particle mixtures, such as particle clustering and ejection from large-eddy turbulent structures, as well

  16. Apparatus for measuring the flow rate of a heat carrier and injection wells

    Energy Technology Data Exchange (ETDEWEB)

    Putilov, M.F.; Bar-Sliva, V.I.; Dichenko, M.A.; Nikiforov, Yu.V.; Petrov, A.I.; Turchaninov, Yu.N.

    1981-01-01

    A device is proposed for measuring the flow rate of the heat carrier in N wells, which contains a housing, turbine ( a permanent magnet is attached to the shaft eccentrically), a reed relay, a secondary converter and a power supply. In order to expand the measurement range by developing torque in the turbine it is equipped with additional reed relay, which is installed diametrically opposite the primary reed relay, and it also has a breaking unit made in the form of an additional permanent magnet placed on the turbine shaft. There was also a torodial core with a two-section winding and a winding power supply polarity switch in the frame. The primary and secondary reed relays are connected to the winding power supply polarity switch circuit. It in turn is connected to the secondary converter. In order to assure the possibility of changing the slope of the flow rate converter into a number of turbine revolutions it is equipped with a frequency to voltage converter with a setting mechanism. The frequency to voltage converter input is connected to the secondary converter, and the output is connected to the power supply source.

  17. Standardization of the water heat carrier quality at Russian thermal power plants

    Science.gov (United States)

    Larin, B. M.; Larin, A. B.; Suslov, S. Yu.; Kirilina, A. V.

    2017-04-01

    The necessity of developing a new industry-specific standard of the heat carrier quality for the operating, newly commissioned, and prospective power-generating units of the thermal power plants is substantiated. The need of extending the scope of the automatic chemical monitoring and the possibility of indirect measurements of some basic standardized and diagnostic indices of the water chemistry using the specific conductance are shown. Investigations proved the possibility of automatic chemical monitoring of the phosphating of the drum boilers and quantitative control of potentially acidic impurities in the feed water in oncethrough boilers. The normative STO NP INVEL document developed at OAO VTI in 2009 is proposed as the basis for alterations and amendments. A new index, the total organic carbon, is introduced into this document. The standardized value of this index in the drum boiler feed water and steam is 100 μg/dm3. According to the above normative document, the scope of the chemical monitoring should be extended by measurements of the specific conductance of the direct and H-cation samples of both the feed and the boiler water. The content of chlorides should also be standardized. For the first time, normative restrictions are suggested on amine-containing water chemistry of the power-generating units with the combined cycle gas turbines. Flowcharts are proposed for pretreatment of the make-up water on the basis of low-mineralized natural waters with high organic substance contents, which reduces the oxidizability by 70-80%.

  18. Stabilizing Cr species in incinerator fly ashes with/without kaolin addition through a firing process: a molecular study on heated Cr.

    Science.gov (United States)

    Wei, Yu-Ling; Wang, Hsi-Chih; Peng, Yen-Shiun

    2017-07-01

    Cr speciation in Cr-sorbing washed incinerator fly ash (IFA) after heating up to 1100°C is temperature dependent. Higher temperature leads to a greater level of chemical reduction of Cr(VI) that is considerably more toxic than Cr(III). Most Cr(VI) sorbed washed IFA is effectively transformed into Cr(III) after heating to 1100°C for 2 h, as indicated by the disappearance of hexavalent pre-edge peak of Cr K-edge X-ray absorption near edge structure (XANES) spectrum. After heating the Cr-sorbing IFA to 100°C and 500°C for 2 h, water-soluble CaCrO4 is determined to be the principal Cr species due to the chemical reaction between the sorbed Cr(VI) and CaO components of washed fly ash, based on the comparison between sample and reference XANES spectra. Replacing half of the washed fly ash with kaolin could effectively reduce all Cr(VI) after heating to ≧ 900°C for 2 h.

  19. 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...

  20. 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.

  1. 固体热载体热解霍林河褐煤实验研究%Experiment study on pyrolysis of Huolinhe lignite with solid heat carrier

    Institute of Scientific and Technical Information of China (English)

    曲旋; 张荣; 孙东凯; 毕继诚

    2011-01-01

    Pyrolysis of Huolinhe lignite with solid heat carrier was carried out in a moving bed reactor with the capacity of 10 kg/h. The solid heat carrier used in the experiment was the circulating ash from a 75 t/h CFB boiler. The effects of pyrolysis temperature, residence time and coal particle size on the yields and composition of products were studied. It is found that the gas yield increases with the increasing pyrolysis temperature. The yield of tar reaches a maximum of 4.94% at 520 ℃. The heating value of pyrolysis gas is from 19.80 MJ/m3 to 23.20 MJ/m3. Some useful compounds, such as BTX and PCX, could be obtained from pyrolysis tar and the contents of them are much higher than those from a bituminous pyrolysis tar. Moreover, the pyrolysis char exhibits good combustion characteristic. The sulfur content of pyrolysis char is notably lower than that in raw coal, which benefits to reduce the desulphurization burden of the CFB boiler.%在处理量为10kg/h的粉煤-固体热载体移动床实验装置上,以循环灰为热载体对其进行了热解特性评价实验.考察了热解温度(460℃~610℃)、反应时间(6min~8min)及煤粒粒径对热解产物产率和组成的影响.结果表明,随着热解温度的升高,气体产率增大;焦油产率在520℃时达到最大值4.94%.热解煤气的热值为19.80MJ/m3~23.20MJ/m3.与淮南烟煤相比,热解焦油中BTX、PCX的含量较高,特别是PCX的含量在反应温度为610℃时达到23.82%.热解半焦具有很好的燃烧特性而且硫含量明显低于原煤,有利于减轻循环流化床锅炉的脱硫负荷.

  2. Lightweight Heat Resistant Geopolymer-based Materials Synthesized from Red Mud and Rice Husk Ash Using Sodium Silicate Solution as Alkaline Activator

    Directory of Open Access Journals (Sweden)

    Hoc Thang Nguyen

    2017-01-01

    Full Text Available Geopolymer is an inorganic polymer composite with potentials to replace Ordinary Portland Cement (OPC-based materials in the future because of its lower energy consumption, minimal CO2 emissions and lower production cost as it utilizes industrial waste resources. Hence, geopolymerization and the process to produce geopolymers for various applications like building materials can be considered as green industry. Moreover, in our study, the raw materials we used are red mud and rice husk ash, which are are industrial and agricultural wastes that need to be managed to reduce their impact to the environment. The red mud and rice husk ash combined with sodium silicate (water glass solution were mixed to form geopolymer materials. Moreover, the geopolymer specimens were also tested for heat resistance at a temperature of 1000°C for 2 hours. Results suggest high heat resistance with an increase of compressive strength after exposed at high temperature.

  3. Characterization of PAHs within PM 10 fraction for ashes from coke production, iron smelt, heating station and power plant stacks in Liaoning Province, China

    Science.gov (United States)

    Kong, Shaofei; Shi, Jianwu; Lu, Bing; Qiu, Weiguang; Zhang, Baosheng; Peng, Yue; Zhang, Bowen; Bai, Zhipeng

    2011-07-01

    Polycyclic aromatic hydrocarbons within PM 10 fraction of ashes from two coke production plants, one iron smelt plant, one heating station and one power plant were analyzed with GC-MS technique in 2009. The sum of 17 selected PAHs varied from 290.20 to 7055.72 μg/g and the amounts of carcinogenic PAHs were between 140.33 and 3345.46 μg/g. The most toxic ash was from the coke production plants and then from the iron smelt plant, coal-fired power plant and heating station according to BaP-based toxic equivalent factor (BaPeq) and BaP-based equivalent carcinogenic power (BaPE). PAHs profile of the iron smelt ash was significantly different from others with coefficient of divergence value higher than 0.40. Indicatory PAHs for coke production plants, heating station and coal-fired power plant were mainly 3-ring species such as Acy, Fl and Ace. While for iron smelt plant, they were Chr and BbF. Diagnostic ratios including Ant/(Ant + Phe), Flu/(Flu + Pyr), BaA/Chr, BbF/BkF, Ind/BghiP, IND/(IND + BghiP), BaP/BghiP, BaP/COR, Pyr/BaP, BaA/(BaA + Chr), BaA/BaP and BaP/(BaP + Chr) were calculated which were mostly different from other stacks for the iron smelt plant.

  4. Studying the melting behaviour of fly ash from the incineration of MSW using viscosity and heated stage XRD data

    DEFF Research Database (Denmark)

    Arvelakis, Stelios; Folkedahl, B.; Frandsen, F. J.;

    2008-01-01

    The purpose of the present study has been to investigate the melting behaviour of fly ashes from the incineration of MSW (municipal solid waste). Four fly ash samples from the Svendborg WtE (waste-to-energy) plant (2nd-3rd pass, super-heater, economizer, ESP), in Denmark, have been investigated...

  5. Thermodynamic analysis of alternate energy carriers, hydrogen and chemical heat pipes

    Science.gov (United States)

    Cox, K. E.; Carty, R. H.; Conger, W. L.; Soliman, M. A.; Funk, J. E.

    1976-01-01

    Hydrogen and chemical heat pipes were proposed as methods of transporting energy from a primary energy source (nuclear, solar) to the user. In the chemical heat pipe system, primary energy is transformed into the energy of a reversible chemical reaction; the chemical species are then transmitted or stored until the energy is required. Analysis of thermochemical hydrogen schemes and chemical heat pipe systems on a second law efficiency or available work basis show that hydrogen is superior especially if the end use of the chemical heat pipe is electrical power.

  6. Thermodynamic analysis of alternate energy carriers, hydrogen and chemical heat pipes

    Science.gov (United States)

    Cox, K. E.; Carty, R. H.; Conger, W. L.; Soliman, M. A.; Funk, J. E.

    1976-01-01

    Hydrogen and chemical heat pipes were proposed as methods of transporting energy from a primary energy source (nuclear, solar) to the user. In the chemical heat pipe system, primary energy is transformed into the energy of a reversible chemical reaction; the chemical species are then transmitted or stored until the energy is required. Analysis of thermochemical hydrogen schemes and chemical heat pipe systems on a second law efficiency or available work basis show that hydrogen is superior especially if the end use of the chemical heat pipe is electrical power.

  7. High-speed pyrolysis with circulating heat carriers; Schnell-Pyrolyse mit zirkulierenden Waermetraegern

    Energy Technology Data Exchange (ETDEWEB)

    Schmalfeld, J.; Albrecht, J.; Solmaz, S.; Zentner, U. [Lurgi Energie und Umwelt GmbH, Frankfurt am Main (Germany)

    1998-09-01

    Yields and product compositions of pyrolysis reactions depend on the mode of heat supply, the temperature level, and the time of residue at reaction temperature. Using hot circulating granular materials mixed with solid or liquid materials (e.g. biogenic or hydrocarbon-rich residues and waste materials or refinery residues), the following important processes can be investigated: Separation of pyrolysis reaction and heat supply - accurate, optimal temperature levels for pyrolysis, e.g. between 5000 and 850 degrees centigrade - undiluted, unmixed pyrolysis gas - short times of residue of the pyrolysis gas for suppression of secondary reactions. (orig.) [Deutsch] Ausbeuten und Produktzusammensetzung von Pyrolyse-Reaktionen werden weitestgehend durch die Art und Weise der Waermezufuhr, das Temperaturniveau und die Verweilzeit bei Reaktionstemperatur bestimmt. Mit Hilfe des Prinzips heisser, umlaufender, koerniger Waermetraeger in Vermischung - fuer die Pyrolyse-Reaktion - mit festen oder fluessigen Einsatzstoffen (z.B. biogene oder kohlenwasserstoffreiche Rest-/Abfallstoffe, Raffinerie-Rueckstaende) lassen sich folgende wichtige, haeufig gewuenschte Vorgaenge realisieren: - Trennung von Pyrolyse-Reaktion und Waermeversorgung - Temperaturgenaue Pyrolyse-Reaktion auf gewuenschtem, optimalem Niveau waehlbar zwischen z.B. 5000 C und 850 C - Erhalt eines unverduennten, unvermischten Pyrolysegases - Kurze Verweilzeiten des Pyrolysegases zur Unterdrueckung von Sekundaerreaktionen. (orig.)

  8. 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.

  9. Study of the potential valorisation of heavy metal contaminated biomass via phytoremediation by fast pyrolysis: Part I. Influence of temperature, biomass species and solid heat carrier on the behaviour of heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    C. Lievens; J. Yperman; J. Vangronsveld; R. Carleer [Hasselt University, Diepenbeek (Belgium). Laboratory of Applied Chemistry

    2008-08-15

    Presently, little or no information of implementing fast pyrolysis for looking into the potential valorisation of heavy metal contaminated biomass is available. Fast pyrolysis of heavy metal contaminated biomass (birch and sunflower), containing high amounts of Cd, Cu, Pb and Zn, resulting from phytoremediation, is investigated. The effect of the pyrolysis temperature (623, 673, 773 and 873 K) and the type of solid heat carrier (sand and fumed silica) on the distribution of the heavy metals in birch and sunflower pyrolysis fractions are studied. The goal of the set-up is 'concentrating' heavy metals in the ash/char fraction after thermal treatment, preventing them to be released in the condensable and/or volatile fractions. The knowledge of the behaviour of heavy metals affects directly future applications and valorisation of the pyrolysis products and thus contaminated biomass. They are indispensable for making and selecting the proper thermal conditions for their maximum recovery. In view of the future valorisation of these biomasses, the amounts of the pyrolysis fractions and the calorific values of the obtained liquid pyrolysis products, as a function of the pyrolysis temperature, are determined. 46 refs., 8 figs., 4 tabs.

  10. Towards simultaneous achievement of carrier activation and crystallinity in Ge and GeSn with heated phosphorus ion implantation: An optical study

    Science.gov (United States)

    D'Costa, Vijay Richard; Wang, Lanxiang; Wang, Wei; Lim, Sin Leng; Chan, Taw Kuei; Chua, Lye Hing; Henry, Todd; Zou, Wei; Hatem, Christopher; Osipowicz, Thomas; Tok, Eng Soon; Yeo, Yee-Chia

    2014-09-01

    We have investigated the optical properties of Ge and GeSn alloys implanted with phosphorus ions at 400 °C by spectroscopic ellipsometry from far-infrared to ultraviolet. The dielectric response of heated GeSn implants displays structural and transport properties similar to those of heated Ge implants. The far-infrared dielectric function of as-implanted Ge and GeSn shows the typical free carrier response which can be described by a single Drude oscillator. Bulk Ge-like critical points E1, E1 + Δ1, E0', and E2 are observed in the visible-UV dielectric function of heated Ge and GeSn indicating single crystalline quality of the as-implanted layers. Although the implantation at 400 °C recovers crystallinity in both Ge and GeSn, an annealing step is necessary to enhance the carrier activation.

  11. Ash in the Soil System

    Science.gov (United States)

    Pereira, P.

    2012-04-01

    , climate/meteorological conditions after the ash spread/fire and soil background characteristics. In addition, after the fire heating can change soil original properties increasing the complexity of the ash effects on soil properties. After fire, ash is highly dynamic and very easily transported by wind until the first rains. When wetted, ash compacts and binds onto soil surface, and wind has low capacity to transport it. The post-rain ash dynamic is influenced by water erosion (in slope areas), infiltration into soil profile and vegetation recuperation. This means that ash produced in one place will have implications in other areas, including not burned areas (e.g wind transport and water erosion). This is a clear indication that ash effects go much further than the fire affected area. Due the heterogeneity of soil and ash properties and their dynamic across the landscape, the impacts of ash on soil system can be diverse, producing a mosaic of different effects and responses after ash treatment and/ or fire. In this communication it will be presented and discussed the advances and scientific development of ash effects and dynamic in soil system.

  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. 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.)

  14. Accurate quantification and transformation of arsenic compounds during wet ashing with nitric acid and microwave assisted heating.

    Science.gov (United States)

    Goessler, W; Pavkov, M

    2003-06-01

    Arsenous acid, dimethylarsinic acid (DMA), methylarsonic acid (MA), arsenic acid, arsenobetaine bromide (AB), trimethylarsine oxide (TMAO), arsenocholine iodide (AC), and tetramethylarsonium iodide (TETRA) were heated in a microwave autoclave with nitric acid to 100-300 degrees C. The arsenic compounds in the digests were separated with anion- and cation-exchange chromatography and determined with an inductively coupled plasma mass spectrometer as arsenic-specific detector. Arsenous acid was completely oxidized to arsenic acid at 100 degrees C. For a complete oxidation of MA and DMA to arsenic acid temperatures > 220 degrees C and > 280 degrees C were necessary. AB decomposed to arsenic acid via TMAO. Complete conversion was only obtained after heating the sample for 90 min to 300 degrees C. For a complete conversion of TMAO similar harsh conditions were necessary. AC was already substantially degraded to TMAO, TETRA and two unknown compounds at 100 degrees C. The unknown arsenic compounds were found only in the digests up to 160 degrees C. Quantitative conversion of AC to arsenic acid went also via TMAO. At temperatures above 220 degrees C TETRA started to convert to TMAO, which then was further converted to arsenic acid. To investigate whether the results obtained for the arsenic standards are transferable to real samples, the certified reference material DORM-2 was also heated in nitric acid with variable digestion temperatures and times. For an almost complete conversion of the AB present in DORM-2 90 min at 300 degrees C were necessary. Total organic carbon (TOC) was less or = 260 degrees C for 60 min. UV photo-oxidation of DORM-2 was investigated as an alternative sample decomposition. Only 6% of AB was converted to arsenic acid when DORM-2 was irradiated for 2 h at 1000 W. In contrast to microwave heating substantial amounts of MA were observed as degradation product.

  15. Estimating exergy prices for energy carriers in heating systems: Country analyses of exergy substitution with capital expenditures

    NARCIS (Netherlands)

    Muller, A.; Kranzl, L.; Tuominen, P.; Boelman, E.; Molinari, M.; Entrop, A.G.

    2011-01-01

    Exergy represents the ability of an energy carrier to perform work and can be seen as a core indicator for measuring its quality. In this article we postulate that energy prices reflect the exergy content of the underlying energy carrier and that capital expenditures can substitute for exergy to som

  16. Pilot Test for Oil Displacement with Combined Heat Carrier in HYS Oilfield%HYS 油田复合热载体驱油先导试验

    Institute of Scientific and Technical Information of China (English)

    翁小红; 马哲斌; 肖见; 刘江林; 侯庆宇

    2012-01-01

    HYS油田是国内最早进行热采的超浅层稠油区块,但是常规热采技术开发超浅层稠油难度大,为提高原油采收率,开展了复合热载体试验.第一批试验井主要依靠复合热载体,辅以少量蒸汽,驱油效果差;第二批试验井综合应用了复合热载体、蒸汽和发泡剂,驱油效果较好.试验结果表明,复合热载体主要为非凝结气体,本身焓值低,需要蒸汽辅助方能起作用.组合注汽可以防止汽窜、形成规模效应,是复合热载体的最佳注汽方式,并在HYS油田克上组油藏取得了比较好的驱油效果.先导试验结果表明,复合热载体技术可以改善超浅层稠油驱油效果,提高采收率,可进行现场应用试验.%HYS Oilfield is the first area of thermal recovery for heavy oil in ultra-shallow formations in China,but it is hard to develop heavy oil from ultra-shallow reservoir by conventional thermal recovery. In order to enhance recovery, experiment of combined thermal carriers has been carried out. The first sets of tests are made by combined heat carrier and a small amount of steam,the effect is poor in displacement of oil;the second sets of tests are made by combined heat carrier, steam and foamer,with better results ob-tained. The testing results show that combined thermal carrier is mainly non-condensed gas, with low en-thalpy value,requiring the assistance of steam to work well. Combined steam injection can prevent steam channeling,and produce scale effect,that is the best method of steam injection by combined heat carrier, and has obtained good effect in T2k formation of HYS Oilfield. Combined heat carrier technique can im-prove heavy oil displacement effect in ultra-shallow formations,enhance oil recovery,and provide guidance for its application in the future.

  17. 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.)

  18. 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.)

  19. The value of energy carriers

    NARCIS (Netherlands)

    Gool, W. van

    1987-01-01

    The value of energy carriers can be described thermodynamically by the amount of heat (enthalpy method) or work (exergy or availability method) that can be obtained from the carriers. Prices for energy carriers are used in economics to express their values. The prices for energy carriers are often r

  20. 褐煤固体热载体催化热解研究进展%Research Progress on Catalysis Themolysis of Lignite Solid Heat Carrier

    Institute of Scientific and Technical Information of China (English)

    李文英; 喻长连; 李晓红; 邓靖

    2012-01-01

    综述了国内外褐煤固体热载体催化热解技术研究进展,对比分析了传统固体热载体热解工艺和耦合热解集成工艺特点,以及使用的固体热载体催化性能,明确了循环流化床耦合低温热解多联产技术是褐煤清洁高效综合利用适合的工艺,指出该集成工艺不仅可以优化产物组成、增加产率和提高能量利用效率,还可实现热、电、气、油、焦多联供,提升煤的综合利用价值。最后对固体催化热载体本身及其制备过程中存在的问题和研究方向提出了相应的建议。%The paper introduced the research progress on the lignite themolysis technology of the solid heat carrier at home and abroad. The comparison and analysis on the themolysis technique of the solid heat carrier and the coupling themolysis technology as well as the catalysis performances of the applied solid heat carrier were conducted. The study results showed that the coupling low temperature themolysis multi link production technology of the circulating fluidized bed would be a suitable technique to clean and high efficient comprehensive utilization of lignite. The author pointed out that the integrated technique would not only optimize the product composition, improve the production rate and increase the energy utilization efficiency, could realize the heat, electric power, gas, oil, coke and other multi production and supply and could improve the coal comprehensive utilization value. In addition, according to the problems existed in the solid heat carrier and the preparation, the relative improved proposals and future research prospects were provided.

  1. Discussion on Effective Utilization of Waste Heat from Coal Fired Heat Carrier Furnace%燃煤热载体加热炉余热有效利用的探讨

    Institute of Scientific and Technical Information of China (English)

    张庆金

    2016-01-01

    本文介绍了燃煤热载体加热炉的余热利用现状,对余热利用的能效进行了分析,指出一些用热单位虽然采用余热设备降低了加热炉排烟温度,但余热设备产生的新能源却没有用途。提出了余热利用的多种方式,希望用热单位采用符合自身特点的余热利用方式,将节能工作落到实处。%This paper introduces the coal-fired heat carrier furnace waste heat utilization, has carried on the analysis on the efifciency of waste heat utilization, points out that some thermal units while reduce the lfue gas temperature of heating furnace with heat recovery equipment, but the heat generated by the equipment without energy use. We put forward a variety of ways of utilization of waste heat, want to use thermal units with their own characteristics of waste heat utilization, to implement energy-saving work.

  2. Rapid Sintering of Silica Xerogel Ceramic Derived from Sago Waste Ash Using Sub-millimeter Wave Heating with a 300 GHz CW Gyrotron

    Science.gov (United States)

    Aripin, Haji; Mitsudo, Seitaro; Sudiana, I. Nyoman; Tani, Shinji; Sako, Katsuhide; Fujii, Yutaka; Saito, Teruo; Idehara, Toshitaka; Sabchevski, Sliven

    2011-06-01

    In this paper, we present and discuss experimental results from a microwave sintering of a silica-glass ceramic, produced from a silica xerogel extracted from a sago waste ash. As a radiation source for the microwave heating a sub-millimeter wave gyrotron (Gyrotron FU CW I) with an output frequency of 300 GHz has been used. The powders of silica xerogel have been dry pressed and then sintered at temperatures ranging from 300°C to 1500°C. The influence of the sintering temperature on the technological properties such as porosity and bulk density was studied in detail. Furthermore, X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy have been used in order to study the structure of the produced silica glass-ceramics. It has been found that the silica xerogel crystallizes at a temperature of 800°C, which is about 200°C lower than the one observed in the conventional process. The silica xerogel samples sintered by their irradiation with a sub-millimeter wave at 900°C for 18 minutes are fully crystallized into a silica glass-ceramic with a density of about 2.2 g/cm3 and cristobalite as a major crystalline phase. The results obtained in this study allow one to conclude that the microwave sintering with sub-millimeter waves is an appropriate technological process for production of silica glass-ceramics from a silica xerogel and is characterized with such advantages as shorter times of the thermal cycle, lower sintering temperatures and higher quality of the final product.

  3. Fusion characteristics of volcanic ash relevant to aviation hazards

    Science.gov (United States)

    Song, Wenjia; Hess, Kai-Uwe; Damby, David E.; Wadsworth, Fabian B.; Lavallée, Yan; Cimarelli, Corrado; Dingwell, Donald B.

    2014-04-01

    The fusion dynamics of volcanic ash strongly impacts deposition in hot parts of jet engines. In this study, we investigate the sintering behavior of volcanic ash using natural ash of intermediate composition, erupted in 2012 at Santiaguito Volcano, Guatemala. A material science procedure was followed in which we monitored the geometrical evolution of cylindrical-shaped volcanic ash compact upon heating from 50 to 1400°C in a heating microscope. Combined morphological, mineralogical, and rheological analyses helped define the evolution of volcanic ash during fusion and sintering and constrain their sticking potential as well as their ability to flow at characteristic temperatures. For the ash investigated, 1240°C marks the onset of adhesion and flowability. The much higher fusibility of ash compared to that of typical test sands demonstrates for the need of a more extensive fusion characterization of volcanic ash in order to mitigate the risk posed on jet engine operation.

  4. 基于电力载波的供暖温控系统%The Heating Temperature Control System Based on Power Line Carrier

    Institute of Scientific and Technical Information of China (English)

    石鑫; 盛碧琦; 王春雨

    2016-01-01

    A heating temperature control system is presentd based on power line carrier against the problems of com⁃plex structure,low accuracy and unable to count temperature of traditional heating thermostat. The design principle of heating temperature control system based on power line carrier is highlighted and the whole hardware and soft⁃ware system is analyzed,then we designed a related circuitry to test the experiment. The result of experiments shows that the heating temperature control system designed has many advantages,such as simple circuit structure,high precision and low cost,and it satisfied the requirements of various technical indexes of heating company.%针对传统供暖温控器结构复杂、精度差、无法统计温度等问题,设计了一款基于电力载波的供暖温控系统。文中重点介绍了基于电力线载波的供暖温控系统的设计原理,并对整套系统硬件电路和软件进行了分析,并设计了相关电路进行试验验证。试验结果表明:文章所研究的供暖温控系统具有电路结构简单、精度高、成本低等优点,满足了供暖公司各项技术要求。

  5. 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)

  6. 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...

  7. Possibilities of utilizing power plant fly ashes

    Directory of Open Access Journals (Sweden)

    Mezencevová Andrea

    2003-09-01

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

  8. Rheological analysis of an effect of different deflocculants on the fly-ash slurry

    Science.gov (United States)

    Sarnecki, K.; Bartosik, A.

    2014-08-01

    During the combustion of coal in the combined heat and power plant (CHP), a very large amount of combustion waste, called further as a fly-ash, is produced. It is typical that fly-ash appears during the combustion process of the fine coal and is transported by a pipeline with support of water as a carrier liquid to a pond storage site, where it is disposed. The pond is localized usually a few kilometers from the CHP, which makes it possible that decrease of friction in such a pipeline can result in energy savings of electricity needed for the pump and water needed as a carrier liquid. In the study an efficient method using a few deflocculants for reducing shear stress, and as a consequence viscosity, is demonstrated. The objective of the paper is to improve the efficiency of the hydrotransport of the fly-ash slurry by adding own designed additives. During the experiments a solids concentration by weight was determined from procured raw material in order to compute the real value occurring in industrial conditions. In addition, the analysis of the particle size distribution was conducted. The Anton Paar MCR 302 electronic rheometer was used to measure the dependence of shear stress and viscosity vs shear rate in the fly-ash existing in the CHP. Another part of the analysis was focused on the additives (deflocculants), to examine their influence on the reduction of the shear stress. The paper proves positive deflocculants impact on the rheological properties of the fly-ash slurry. The results of measurements are presented as figures and conclusions.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-07-01

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

  10. Comparative analysis of heat transfer,ash deposition and attrition performances on different extended surfaces%不同扩展换热面传热、积灰、磨损特性对比

    Institute of Scientific and Technical Information of China (English)

    赵虹; 周霭琳; 施浩勋; 陈理帅; 邓芙蓉; 杨建国; 胡劲逸

    2015-01-01

    To optimize and select the low temperature heat exchanger,comparative analysis on heat transfer, ash deposition and attrition performances of H-finned tubes and spiral finned tubes was conducted,by ther-modynamic calculation and numerical simulation methods.The results show that,with conventional struc-tural parameters,the spiral finned tube with unit length has higher heat transfer efficiency,and its steel consumption (flow resistance)is only 42.87% (61.45%)of that of the H-finned tube when heat transfer rate is the same.Due to the special groove structure,the swirling generated in the H-finned tube has the opposite direction to the malnstream.It shocks to the tube lee side vertically,so the H-finned tube can a-chieve ash self-removing.The abrasion of the H-finned tubes is lighter overall,and the fin has no sideway scouring.Therefore,the spiral finned tube has better heat transfer property while the H-finned tube has ad-vantages in ash deposition and attrition resistance.%为了对低温换热器优化选型,利用热力计算和数值模拟的方法,对比分析了螺旋肋片管和 H型鳍片管的传热、积灰、磨损特性.结果表明:常规结构参数下,单位长度的螺旋肋片管具有更大的换热效率,在达到相同换热量时,其钢材消耗是 H 型鳍片管的42.87%,烟气阻力是 H型鳍片管的61.45%;H 型鳍片管由于其特殊的沟槽结构,形成的涡流方向与主流速度相反,垂直冲刷基管背风面,达到自清灰的目的,其鳍片无侧向气流冲刷,整体磨损较轻.因此,螺旋肋片管的换热性能更好,但 H 型鳍片管的防积灰和耐磨性均优于螺旋肋片管.

  11. Volcanic ash impacts on critical infrastructure

    Science.gov (United States)

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

    2012-01-01

    supply managers include: monitoring turbidity levels in raw water intakes, and if necessary increasing chlorination to compensate for higher turbidity; managing water demand; and communicating monitoring results with the public to allay fears of contamination. Ash can cause major damage to wastewater disposal systems. Ash deposited onto impervious surfaces such as roads and car parks is very easily washed into storm drains, where it can form intractable masses and lead to long-term flooding problems. It can also enter wastewater treatment plants (WWTPs), both through sewer lines and by direct fallout. Damage to modern WWTPs can run into millions of dollars. Ash falls reduce visibility creating hazards for ground transportation. Dry ash is also readily remobilised by vehicle traffic and wind, and dry and wet ash deposits will reduce traction on paved surfaces, including airport runways. Ash cleanup from road and airports is commonly necessary, but the large volumes make it logistically challenging. Vehicles are vulnerable to ash; it will clog filters and brake systems and abrade moving parts within engines. Lastly, modern telecommunications networks appear to be relatively resilient to volcanic ash fall. Signal attenuation and interference during ash falls has not been reported in eruptions over the past 20 years, with the exception of interference from ash plume-generated lightning. However, some telecommunications equipment is vulnerable to airborne ash, in particular heating, ventilation and air-conditioning (HVAC) systems which may become blocked from ash ingestion leading to overheating. This summary of volcanic ash impacts on critical infrastructure provides insight into the relative vulnerability of infrastructure under a range of different ashfall scenarios. Identifying and quantifying these impacts is an essential step in building resilience within these critical systems. We have attempted to consider interdependencies between sectors in a holistic way using

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-31

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

  14. Water as carrier of information of heat shock and drug effect between two groups of Adhatoda vasica plants

    Directory of Open Access Journals (Sweden)

    N C Sukul

    2012-06-01

    Full Text Available Adhatoda vasica Nees plants were grown in 50 earthen pots, which were divided into 5 batches A, B, C, D, and E. Of these A, B and C, D were arranged into two separate parallel pairs. One leaf of each plant of an adjacent pair was immersed in sterile tap water in a beaker. Adjacent beakers in each pair A B or C D were connected by polythene tubes containing wet cotton threads. One leaf of each plant of A was given heat shock by immersing a leaf in hot water for 5 min. One leaf of each plant of C was treated with Cantharis vesicatoria 200c. Batch E served as the unstressed and untreated control. One hour after heat shock or drug treatment all the leaves were harvested and their proteins were extracted by chilled protein extraction buffer. Proteins were separated by Fast Protein Liquid Chromatography (FPLC. Protein profiles of A, B and C, D showed marked similarity with respect to expression and repression of some proteins. It is concluded that the effect of heat shock and drug treatment is transmitted through water in the capillaries of cotton threads connecting the pairs of plants. It is assumed that heat shock or drug treatment altered locally the water structure in the leaves which was propagated through global network of water structure over the protein network in the whole plants, and from there to the interfacial water in the beakers and cotton threads. A homeopathic potency is thought to be specifically structured water which influences the water structure in the treated organism.

  15. Analytical model of unsteady-state convective heat transfer between the heat carrier and the finite sizes plate adjusted for the thermal relaxation

    Directory of Open Access Journals (Sweden)

    Makarushkin Danila

    2017-01-01

    Full Text Available A hyperbolic boundary value problem of the thermal conduction of a two-dimensional plate with the third kind boundary conditions is formulated. The transient thermal process in the plate is due to the temperature changes of the external medium over time and along the plate length, and also by a multiple step change of the plate surface heat transfer coefficient throughout the transient process. An analytical solution with improved convergence adjusted for thermal relaxation and thermal damping is obtained for the temperature field in the plate.

  16. 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.

  17. 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.

  18. 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.

  19. The behavior of ash species in suspension fired biomass boilers

    DEFF Research Database (Denmark)

    Jensen, Peter Arendt

    of advanced deposit probe measurements have been conducted on biomass powerplants. The measurements have provided insight into the relations between the chemical composition of fuel ash, fly ash and deposits. Furthermore the measurements have provided quantitative data on deposit formation rates as a function...... the interface to the steam tube metal surface. Especially an increased tube temperature makes it more demanding to remove the ash deposit. Modelling of the deposit formation process have been developed by combining sub-models of the ash formation process, the condensation of ash species on tube surfaces, ash...... particle deposition, heat transfer in the deposit and deposit sintering. The model mainly providesinformation on how changes in fuel ash composition and local conditions influences depositformation rate and deposit chemistry. Comparison of the modeling results with laboratory andfull scale data shows...

  20. [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...

  1. Aircraft Carriers

    DEFF Research Database (Denmark)

    Nødskov, Kim; Kværnø, Ole

    There are many indications that China is actively researching the design of an aircraft carrier. It is unknown whether China will initiate the actual acquisition of a carrier, but the indications that are available of their research into aircraft carriers and carrier-capable aircraft, as well...... as their purchases of aircraft carrier systems, makes it more than likely that the country is preparing such an acquisition. China has territorial disputes in the South China Sea over the Spratly Islands and is also worried about the security of its sea lines of communications, by which China transports the majority...... of its foreign trade, as well as its oil imports, upon which the country is totally dependent. China therefore has good reasons for acquiring an aircraft carrier to enable it to protect its national interests. An aircraft carrier would also be a prominent symbol of China’s future status as a great power...

  2. Design and implementation of device for effective utilization of residual heat from the back-end of organic heat carrier boiler%有机热载体锅炉尾部高效余热利用装置的设计与应用

    Institute of Scientific and Technical Information of China (English)

    郭建平; 李文炜; 楼云定

    2009-01-01

    Organic heat carrier boilers were widely used in textile, printing and dyeing industries. Due to the special processes of high temperature stereotype and dyeing & finishing, as well as the structure and operating principle of organic heat carrier boilers,the temperature of exhaust gas from the back-end of the organic heat carrier boilers reaches up to 300℃, leading to enormous waste of heat energy. In order to reduce the loss of heat energy, by using heat pipe technology, this paper designed and developed a reasonable-structured, effective and easy-to-operate device for recycling of the high-temperature flue gas from the back-end of organic heat carrier boilers ,through recovery and utilization of the residual heat in the high-temperature flue gas, improving the comprehensive thermal efficiency of organic heat carrier boiler and maximizing the effectiveness of energy conservation and emission reduction.%有机热栽体锅炉广泛应用于纺织、印染行业,由于高温定型和染整的特殊工艺以及有机热载体锅炉的构造和运行原理造成其尾部排烟温度在300℃左右,产生巨大的热能浪费.为减少热能损失,通过高温烟气的余热回收利用,提高有机热载体锅炉的综合热效率,可实现节能降耗和减排.本课题运用热管技术设计研制了结构合理、操作方便、高效的有机热载体锅炉尾部高温烟气的回收再利用装置.

  3. 气体热载体法煤热解动力学研究%Kinetic study on coal pyrolysis with gas heat carrier method

    Institute of Scientific and Technical Information of China (English)

    彭宝仔

    2015-01-01

    采用热重分析和气体热载体实验考察了准东煤和神木煤的热解动力学特性,并根据热解动力学模型确定动力学参数. 随热解温度的升高,反应停留时间对半焦收率及半焦挥发分的影响逐渐减小;煤热解活化能与反应停留时间、煤粒径大小均相关. 研究结果对于煤热解工艺工业化具有参考意义.%This paper probes into the pyrolysis kinetic characteristics of Zhundong coal and Shenmu coal with thermogravimetric analysis method and gas heat carrier experiment, and determines the kinetic parameters by established pyrolysis kinetic model. It finds that the impact of reaction residence time on semi-coke yield and its volatile matter decreases with increasing pyrolysis tempera-ture;the pyrolysis activation energies of coals are related to reaction residence time and coal particle size. The study results have great significance on industrialization of coal pyrolysis process.

  4. Effect of Ash on Oxygen Carriers for the Application of Chemical Looping Combustion to a High Carbon Char Effet des cendres sur l’activité des porteurs d’oxygène dans la combustion du charbon en boucle chimique

    Directory of Open Access Journals (Sweden)

    Rubel A.

    2011-02-01

    Full Text Available The application of Chemical Looping Combustion (CLC to solid fuels is being investigated at the University of Kentucky, Center for Applied Energy Research (CAER with the aim of the development of a Pressurized Chemical Looping Combustion/Gasification (PCLC/G process for the generation of electricity from coal. One important aspect of the CLC of solid fuel is the understanding of the effect of ash on the reactivity of Oxygen Carriers (OCs. The effect of ash on the redox capabilities of two different iron oxide OCs and on their ability to oxidize coal char was studied. To determine the effect of ash on the reactivity and recycle of the OCs through multiple redox cycles, fly ash from a coal-fired power plant was used. These experiments were performed in a TGMS system using 500 mg of ash/OC mixtures containing different ash concentrations up to 75%. The reducing gas was composed of 10% H2, 15% CO, 20% CO2, and a balance of Ar and the oxidizing gas was 20% O2 in Ar. Oxidation/reductions were carried to near completion. The ash was found to contain OC activity related to inherent iron present in the ash confirmed by XRD. This resulted in increased weight gain/loss on oxidation/reduction. The rate of oxidation/reduction increased with ash concentration due to increased porosity of the OC/ash mixture and better access of the reactive gases to the OC target sites. The two OCs were then used to combust a beneficiated coal char in the TGMS with the only oxygen supplied by an iron oxide OC. The starting mixture was 10% char and 90% of one of two OCs studied. The spent material containing reduced OC and ash was re-oxidized and 10% more char was added for a second reduction of the OC and oxidation of the added char. This procedure was repeated for 5 cycles increasing the ash concentrations from 5 to 25% in the char/ash/OC mixture. Carbon removal was 92 to 97.8 and 97.3 to 99.7% for the two different iron oxide OCs tested. Ash was not detrimental to the

  5. 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)

  6. 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)

  7. Insight of the fusion behavior of volcanic ash: Implications for Volcanic ash Hazards to Aircraft Safety

    Science.gov (United States)

    Song, Wenjia; Hess, Kai-Uwe; Küppers, Ulrich; Scheu, Bettina; Cimarelli, Corrado; Lavallée, Yan; Sohyun, Park; Gattermann, Ulf; Müller, Dirk; Dingwell, Donald Bruce

    2014-05-01

    The interaction of volcanic ash with jet turbines during via ingestion of ash into engines operating at supra-volcanic temperatures is widely recognized as a potentially fatal hazard for jet aircraft. 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 fusibility of volcanic ash is believed to impact strongly its deposition in the hotter parts of jet engines. Despite this, explicit investigation of ash sintering using standardized techniques is in its infancy. Volcanic ash may vary widely in its physical state and chemical composition between and even within explosive volcanic eruptions. Thus a comparative study of the fusibility of ash which involves a standard recognized techniques would be highly desirable. In this work, nine samples of fine ash, deposited from co-pyroclastic offrom nine different volcanoes which cover a broad range of chemical composition, were investigated. Eight of them were collected from 2001-2009 eruptions. Because of the currently elevated level of eruptive activity and its potential hazards to aircraft safety and the remaining one sample was collected from a 12,121 ± 114 yr B.P. eruption. 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 fusion phenomena as well as determine the volcanic ash melting behavior by defining four characteristic temperatures (shrinkage temperature, deformation temperature, hemispherical temperature, and flow temperature) by means of heating microscope instrument and different thermal analysis methods. Here, we find that there are similar sticking ability and flow behavior of

  8. 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.

  9. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-04-01

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

  11. 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.

  12. 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...

  13. Sulphation characteristics of paper sludge ash

    Energy Technology Data Exchange (ETDEWEB)

    Roh, S.A. [Environmental Systems Research Center, Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of); Kim, S.D. [Environmental Systems Research Center, Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of). Dept. of Chemical and Biomolecular Engineering

    2007-04-15

    Landfills are no longer a viable solution for the disposal of sludge produced from waste water treatment plants because of the decrease in available space, rising fees and growing environmental concerns. However, thermal utilization of this waste may be an economic and sustainable disposal solution. Co-combustion of low heating value sludge with fossil fuels has a positive effect for sulfur dioxide (SO{sub 2}) emissions due to the low sulphur content of biomass fuels and increased sulphur retention in the ash. The sulphur retention is attributed to the formation of sulphates, such as CaSO{sub 4}, K{sub 2}SO{sub 4} and Na{sub 2}SO{sub 4}. The amount of fuel-ash-related sulphur sorption increases during co-combustion. Therefore, sorbents for sulphur reduction may not be required if proper control of the biomass feed is maintained. This paper presented a study in which the sulphation characteristics of calcium-rich paper sludge ash were determined for the use of co-combustion of biomass and coal. The calcium in the paper sludge ash came from the limestone filler used in the manufacturing process to increase the density and whiteness of the paper at 2 paper mills in Korea. A thermobalance reactor along with XRD and SEM-EDX were used for the analysis of sulphated ash to determine the effects of sulphation temperature, particle size and SO{sub 2} concentration on sulphation conversion. The activation energy and pre-exponential factor of sulphation reaction of sludge ash were determined based on the uniform-reaction model. X-ray diffraction analysis revealed that most of the sulphation compounds were CaSO{sub 4}. The sulphation occurred uniformly throughout the ash and the CaSO{sub 4} did not block the outer pore of the sludge ash. The uniform distributions of CaO and other inert minerals in the ash resulted in uniform sulphation with good penetration of SO{sub 2} into pores of the sludge ash without pore blocking during sulphation of CaO. 13 refs., 1 tab., 9 figs.

  14. Soil food web structure after wood ash application

    DEFF Research Database (Denmark)

    Mortensen, Louise Hindborg; Qin, Jiayi; Cruz-Paredes, Carla

    the consequences of returning wood ash to biofuel producing coniferous forest. We that the change in pH and increased availability of nutrients after ash application to forest floor can facilitate an increase in the bacteria to fungi ratio with possible effects for the soil food by applying ash of different......In 2006, the European Council established a mandatory target of 20 % renewable energy of consumption by 2020. Part of the replacement is burning biomass for heating and electricity. ~ Whole tree biomass harvesting for biofuel combustion intensifies removal of nutrients from the by applying ash from...... the combustion back to the system and thus recycle the besides being rich in inorganic nutrients, ash is also very alkaline and contains heavy metals. The ASHBACK project (www.ashback.dk) is a cooperation between three Danish universities other research institutions and stake-holders that aims to investigate...

  15. Synthesis and characterization of zeolites prepared from industrial fly ash

    OpenAIRE

    Franus, Wojciech; Wdowin, Magdalena; Franus, Małgorzata

    2014-01-01

    In this paper, we present the possibility of using fly ash to produce synthetic zeolites. The synthesis class F fly ash from the Stalowa Wola SA heat and power plant was subjected to 24 h hydrothermal reaction with sodium hydroxide. Depending on the reaction conditions, three types of synthetic zeolites were formed: Na-X (20 g fly ash, 0.5 dm3 of 3 mol · dm−3 NaOH, 75 °C), Na-P1 (20 g fly ash, 0.5 dm3 of 3 mol · dm−3 NaOH, 95 °C), and sodalite (20 g fly ash, 0.8 dm3 of 5 mol · dm−3 NaOH + 0.4...

  16. 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...

  17. Wildland fire ash: future research directions

    Science.gov (United States)

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

    2014-05-01

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

  18. High performance fly ash mixed concrete in underground construction of Delhi metro

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, R.; Gupta, A.K.; Garg, R.; Gopalkrishnan, E. [DMRC, New Delhi (India)

    2003-07-01

    The paper describes the comprehensive concrete durability studies carried out for deciding the specifications for the MCIA contract for construction of 4 km of underground metro from Vishwa Vidyalaya station to Kashmere Gate station in India. The study involved adiabatic concrete temperature measurement tests to know the heat generation and temperature rising properties inside concrete mass. The paper describes the background for selection of fly ash as a part replacement up to 30% of cement in concrete including determination of specification, identification of source, collection and transportation by bulk carrier and transfer to storage silo at the concrete batching plant. Control of temperature of concrete during production and after placement requires detailed arrangements for cooling aggregates and water at batching plant and thermal insulation along with curing to the concrete placed at site. Fully tanked membrane waterproofing and special waterproofing details at construction joints also contribute towards achieving the high performance durable concrete structure. 3 refs., 6 figs., 11 tabs.

  19. COAL ASH RESOURCES RESEARCH CONSORTIUM

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    The Coal Ash Resources Research Consortium (CARRC, pronounced �cars�) is the core coal combustion by-product (CCB) research group at the Energy & Environmental Research Center (EERC). CARRC focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of CCBs. CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCB utilization and ensuring its successful application. CARRC continued the partnership of industry partners, university researchers, and the U.S. Department of Energy (DOE) addressing needs in the CCB industry through technical research and development projects. Technology transfer also continued through distribution and presentation of the results of research activities to appropriate audiences, with emphasis on reaching government agency representatives and end users of CCBs. CARRC partners have evolved technically and have jointly developed an understanding of the layers of social, regulatory, legal, and competition issues that impact the success of CCB utilization as applies to the CCB industry in general and to individual companies. Many CARRC tasks are designed to provide information on CCB performance including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC activities from 1993�1998 included a variety of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCBs. The tasks summarized in this report are 1) The Demonstration of CCB Use in Small Construction Projects, 2) Application of CCSEM (computer-controlled scanning electron microscopy) for Coal Combustion By-Product Characterization, 3) Development of a Procedure to Determine Heat of Hydration for Coal Combustion By-Products, 4) Investigation of the Behavior of High

  20. 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.

  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. Research Advances in Directly Heated Cracking of Hydrocarbonsby Heat Carrier Gas——Ⅰ.Pyrolysis Apparatuses and Techniques%热载气体直接加热石油烃裂解研究进展——Ⅰ.裂解装置和技术

    Institute of Scientific and Technical Information of China (English)

    景晓东; 赵月红; 温浩; 许志宏

    2012-01-01

    Recent advances in directly heated cracking using heat carrier gas together with the wide applications in industry are reviewed, focusing on the composition, operating conditions, product yields and the progress of pyrolysis apparatuses of directly heated cracking using heat carrier gas. In addition, the decoking techniques, mechanism and kinetics of hydrocarbons pyrolysis are also summarized up. Finally, the outlook for the future development of directly heated cracking using heat carrier gas is provided and a conclusion is drawn that directly heated cracking using superheated steam produced by combustion of hydrogen and oxygen as heat carrier gas will be one of the most promising techniques for it has the advantages of high feedstock and products flexibility, higher heat efficiency, and lower CO2 emission, and production of synthesis gas by coupling the decoking and pyrolysis processes.%概述了以气体为热载体的石油烃直接加热裂解技术及其应用:介绍了热载气体直接加热石油烃裂解的装置组成、运行条件、产物产率、技术改进及发展状况,分析了裂解反应机理和反应动力学;指出热载气体直接加热裂解具有原料适用性广、产物分布灵活、热效率较高和受结焦影响小等优点,但同时也有裂解装置结构较复杂、缺乏系统性研究数据等不足.最后对热载气体直接加热石油烃裂解的研究进行了展望,指出以氢氧燃烧产生的过热水蒸汽作为热载气体的直接加热裂解技术,在提高换热效率、降低碳排放、扩大原料范围和耦合制取合成气等方面有很大优势,发展前景广阔.

  3. Technology for processing ash from thermal/electric plants without waste products

    Energy Technology Data Exchange (ETDEWEB)

    Tyurnikova, V.I.; Krasnikova, N.A.; Panin, A.S.; Konovalenko, P.F.

    1979-07-01

    Possibility of using flotation for enriching volatile ash from heating/electric power stations are investigated. On ash samples containing 9 percent carbon from the Nikolaev thermal/ electric plant, it was demonstrated that by using flotation with an apolar collector and T-66 reagent, the ash content was increased to 98.6% permitting it to be used for producing high ash construction materials. A foam carbon-containing product from the process has a heat of combustion of 4,000 kilocalories/ kilogram and can be reused as a fuel. Flowsheet for the flotation process is presented.

  4. Hydrothermal synthesis of zeolites from coal fly ash

    OpenAIRE

    Kotova, OB; Shabalin, Igor L; Shushkov, DA; Kocheva, LS

    2015-01-01

    The fly ash, from the combustion of coal to produce energy and heat, is an industrial waste, in which large accumulations represent a serious environmental threat. To reduce the environmental burden and improve the economic benefits of energy production, the science and industry focus on the transformation of coal combustion byproducts into new functional materials. The fly ash was studied by modern analytical methods. As a result of the hydrothermal reaction, several types of zeolites were s...

  5. Production of ceramics from coal fly ash

    Directory of Open Access Journals (Sweden)

    Angjusheva Biljana

    2012-01-01

    Full Text Available Dense ceramics are produced from fly ash from REK Bitola, Republic of Macedonia. Four types of fly ash from electro filters and one from the collected zone with particles < 0.063 mm were the subject of this research. Consolidation was achieved by pressing (P= 133 MPa and sintering (950, 1000, 1050 and 11000C and heating rates of 3 and 100/min. Densification was realized by liquid phase sintering and solid state reaction where diopside [Ca(Mg,Al(Si,Al2O6] was formed. Ceramics with optimal properties (porosity 2.96±0.5%, bending strength - 47.01±2 MPa, compressive strength - 170 ±5 MPa was produced at 1100ºC using the heating rate of 10ºC/min.

  6. 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....

  7. Role of heat-labile serum factor or host complement in the inhibition of Plasmodium falciparum sporogonic stages in Anopheles stephensi by gametocyte carriers' serological factors.

    NARCIS (Netherlands)

    Gouagna, L.C.; Kolk, M. van der; Roeffen, W.; Verhave, J.P.; Eling, W.M.C.; Sauerwein, R.W.; Boudin, C.

    2007-01-01

    This study investigated the significance of serum complement on transmission-reducing activity (TRA) of field sera from 24 infected Plasmodium falciparum gametocyte carriers (from Cameroon) against cultured NF54 P. falciparum. Laboratory-reared Anopheles stephensi were given infectious blood meals

  8. Influence of heat treatment on spray-dried mixtures of Amioca starch and Carbopol 974P used as carriers for nasal drug delivery.

    Science.gov (United States)

    Coucke, D; Pringels, E; Foreman, P; Adriaensens, P; Carleer, R; Remon, J P; Vervaet, C

    2009-08-13

    A mucoadhesive spray-dried starch/poly(acrylic acid) powder underwent different heat treatments in order to induce cross-linking between the functional groups of starch (Amioca) and poly(acrylic acid) (Carbopol 974P). After heat treatment the water-absorbing capacity, viscosity and elasticity of the mucoadhesive powder increased. NMR analysis in combination with FT-IR indicated that heat treatment induced a low degree of cross-linking between the polymers. Nasal administration of Amioca/Carbopol 974P powders without heat treatment resulted in an absolute bioavailability in rabbits of 8.2+/-3.0% for insulin. Due to the difference in water-absorbing capacity (which opened the tight junctions of the nasal mucosa), elasticity and plasticity (which reduced mucociliairy clearance and prolonged residence time) heat treatment at 120 degrees C improved the bioavailability: 26.4+/-21.9, 36.5+/-11.0 and 19.3+/-17.3% after heat treatment during 30 min, 1 h and 4 h, respectively. Heat treatment at 60 degrees C was less efficient. This study demonstrated that the nasal insulin absorption improved via heat treatment of the Amioca/Carbopol 974P powder (prior to the addition of insulin). The bioavailability-enhancing effect of a 1 h heat treatment at 120 degrees C was confirmed using the same polymer matrix in combination with different drugs (salmon calcitonin, human growth hormone and metoprolol tartrate).

  9. A Comparative study Of Catalityc Activity Of Heterogeneous Base Of Banana Stem Ash And Fly Ash On Production Of Biodiesel Byultrasonic

    Directory of Open Access Journals (Sweden)

    Marlinda

    2015-08-01

    Full Text Available Abstract The use of heterogeneous catalysts in the production of biodiesel provides many advantages due to heterogeneous catalysts can be easily separated from the product so that it can be reused. This research using heterogeneous catalysts derived from natural materials namely banana stem ash and coal fly ash containing alkali and alkaline earth elements. The preparation of catalyst from banana stem ash and coal fly ash used activator KOH 1.9 N and impregnation with KNO3 15 and then heated to a temperature of 550 0C for 3 hours. Results of preparation banana stem ash contains potassium of 36.52 and surface area of 41.901 m2g. This work presents the effect of ultrasonic assisted of waste cooking oil with methanol as solvent using banana stem ash and coal fly ash as catalyst. The diameter of catalyst particles of banana stem ash and coal fly ash varied at 50 100 150 200 and 250 mesh. The transesterification reaction was performed in the presence of ultrasonic operating frequency constant at 40 kHz methanol molar ratio to oil of 9 1 and reaction time of 30 minutes. The methyl ester biodiesel content of product was 93.26 of banana stems ash and 57 of coal fly ash respectively. The physical property was compared with the National Indonesia Standard SNI 2006 with a density viscosity cloud point flash point and cetane number.

  10. 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....

  11. Coal ash fusion temperatures -- New characterization techniques, and associations with phase equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Wall, T.F.; Gupta, R.P.; Gupta, S. [Univ. of Newcastle, New South Wales (Australia). Dept. of Chemical Engineering; Creelman, R.A. [R.A. Creelman and Associates, Epping, New South Wales (Australia); Coin, C. [ACIRL Ipswich, Booval, Queensland (Australia); Lowe, A. [Pacific Power, Sydney, New South Wales (Australia)

    1996-12-31

    The well-documented shortcomings of the standard technique for estimating the fusion temperature of coal ash are its subjective nature and poor accuracy. Alternative measurements based on the shrinkage and electrical conductivity of heating samples are therefore examined with laboratory ash prepared at about 800 C in crucibles, as well as combustion ash sampled from power stations. Sensitive shrinkage measurements indicate temperatures of rapid change which correspond to the formation of liquid phases that can be identified on ternary phase diagrams. The existence and extent of formation of these phases, as quantified by the magnitude of peaks in the test, provide alternative ash fusion temperatures. The peaks from laboratory ashes and corresponding combustion ashes derived from the same coals show clear differences which may be related to the evaporation of potassium during combustion and the reactions of the mineral residues to form combustion ash.

  12. 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...

  13. Influence of mineral and chemical composition of coal ashes on their fusibility

    Energy Technology Data Exchange (ETDEWEB)

    Vassilev, S.V.; Kitano, K.; Takeda, S.; Tsurue, T. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Institute of Applied Mineralogy

    1995-10-01

    The relationships between ash-fusion temperature (AFT) and mineral and chemical composition of coals and coal ashes from a wide variety of deposits (41) were studied by a melting test, X-ray diffractometry, light microscopy, differential-thermal, thermogravimetric and chemical analyses. A reliable explanation and prediction of AFT only from the total chemical composition of coal ash is inadequate because most important are the modes of elemental combination (minerals and phases) in coal and coal ash, as well as their behaviour during heating. The coals, which have low-melting temperature ashes, are lower rank coals with increased concentrations of S, Ca, Mg, Fe and Na and respectively, sulphates, carbonates, sulphides, oxides, montmorillonite, and feldspars. The coals with high-melting temperature ashes have an advanced rank and increased contents of Si, Al and Ti and respectively, quartz, kaolinite, illite and rutile, as well as some Fe oxides and siderite. The behaviour of chemical components and various coal and coal-ash minerals during heating is discussed, and their refractory and fluxing influence on ash fusibility is described. Lower AFT is related to increased proportions of the fluxing sulphate, silicate and oxide minerals such as anhydrite, acid plagioclases, K feldspars, Ca silicates and hematite in high-temperature coal ashes. Higher AFT is a result of decreased fluxing minerals and increased refractory minerals such as quartz, metakaolinite, mullite, and rutile in these ashes. Defined softening, hemispherical and fluid ash-fusion temperatures fit various processes of inorganic transformations which are discussed. A reliable explanation and prediction of ash-fusion characteristics can be made when the coal and coal-ash minerals and their amounts, as well as their refractory and fluxing action during heating, are known. 31 refs., 7 figs., 5 tabs.

  14. Fluidized bed combustion of high ash Singareni coal

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, M.K.; Biswas, R.R.; Mukherjee, S.K.; Talapatra, P.C.; Roy, R.U.; Rao, S.K.; Sen, M.M.

    1986-04-01

    Fluid bed combustion is comparatively a new technology for efficient combustion of high ash coals, which constitute the bulk of Indian coal resources. A 2-tonne equivalent steam per hour fluid bed combustion boiler was installed at the CPRI for experimentation with Indian coals and this paper discusses the salient features of tests conducted in the unit with minus 6 mm high ash Singareni coal of Andhra Pradesh. Data on combustion, heat transfer and heat utilization characteristics of the boiler under varying operating conditions show that high ash Singareni coal slacks can be burnt efficiently with high thermal efficiency, combustion efficiency and heat transfer rates from bed to surface in direct contact in a fluid bed combustion boiler. 3 refs., 5 figs., 4 tabs.

  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. Temperature Effects on the Ash Colour of Forest Litter

    Directory of Open Access Journals (Sweden)

    Jolita Dūdaitė

    2011-12-01

    Full Text Available Abstract. Research was carried out to identify the influence of temperature (150, 250, 350, 450, 550ºC on the ash colour of Acer platanoides L. leaf litter and Pinus sylvestris L. needle litter samples collected from deciduous coniferous mixed forest in Lithuania (54º43‘ N 25º19‘ E in April 2010. To achieve the objective, a laboratory experiment was conducted to determine ash samples using the Munsell Colour Chart. The analysis of colours has demonstrated that considering all litter samples, an increase in the temperature of litter heating was found to increase ash colour values (r = 0.92; p = 0.01. All the samples (n = 50 of both litter species were divided into categories 2.5Y (5 samples, 7.5YR (10 samples and 10YR (35 samples. The total black Munsell colour was observed at a temperature of 350ºC for both litter species. Needle ash started turning bright at a temperature of 550ºC while the complete consumption of leaf litter was visible at a temperature of 450ºC. We conclude that the Munsell Colour Chart used for predicting the colour of ash is an informative feature to have the primary classification of ash. It is imperative to analyse the colour of the litter ash of the selected tree species in order to quickly and easily assess and predict their possible impact on the surrounding environment.

  19. 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

  20. 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...

  1. Effect of heat treatment and cooling rate on minority carrier lifetime of Czochralski silicon%热处理和冷却速率对直拉单晶硅少子寿命的影响

    Institute of Scientific and Technical Information of China (English)

    周潘兵; 柯航; 周浪

    2012-01-01

    Effects of heating temperature and cooling rate on the minority carrier lifetime and the interstitial iron concentration of Czochralski silicon(Cz-Si) were investigated. The results show that the interstitial iron concentration is higher and the minority carrier lifetime is lower than the original level when the Cz-Si are heated in the range of 300-1050 ℃ for 40 min and cooled to room temperature at a rate as fast as 50 ℃/s, and the interstitial iron concentration increases and the minority carrier lifetime decreases with increase of heating temperature. When the Cz-Si wafers are heated in the range of 900-1000 ℃ for 40 min and cooled to room temperature at a rate as fast as 50 ℃/s, above 90% of the iron in silicon is in the form of iron precipitates while the other is kept as interstitial iron. When the Cz- Si wafers are heated at 800, 900 and 1000 ℃ for 40 min, followed by cooling at different rates, the interstitial iron concentration increases and the minority carrier lifetime decreases with increase of the cooling rate from 0. 017 to 50 ℃/s.%研究了加热温度与冷却速率对热处理直拉单晶硅少子寿命和间隙铁含量的影响。结果表明,直拉单晶硅在300~1050℃加热40 min,以50℃/s的速率快冷至室温会提高硅片的间隙铁含量,降低硅片的少子寿命;加热温度越高,快冷后硅片的间隙铁含量越高,少子寿命越低;直拉单晶硅片在900~1050℃加热,当以50℃/s的速率快冷至室温,90%以上的铁以沉淀形式存在,其余的铁以间隙态存在。直拉单晶硅片分别经800、900和1000℃加热40 min后在0.017~50℃/s的速率范围冷却,硅片间隙铁含量随冷却速率增加而增加,少子寿命随冷却速率增加而降低,加热温度越高,间隙铁含量上升的幅度越大,而少子寿命下降的幅度越大。

  2. Hydrogen carriers

    Science.gov (United States)

    He, Teng; Pachfule, Pradip; Wu, Hui; Xu, Qiang; Chen, Ping

    2016-12-01

    Hydrogen has the potential to be a major energy vector in a renewable and sustainable future energy mix. The efficient production, storage and delivery of hydrogen are key technical issues that require improvement before its potential can be realized. In this Review, we focus on recent advances in materials development for on-board hydrogen storage. We highlight the strategic design and optimization of hydrides of light-weight elements (for example, boron, nitrogen and carbon) and physisorbents (for example, metal-organic and covalent organic frameworks). Furthermore, hydrogen carriers (for example, NH3, CH3OH-H2O and cycloalkanes) for large-scale distribution and for on-site hydrogen generation are discussed with an emphasis on dehydrogenation catalysts.

  3. Network-ball Machine as the Carrier of Heat Transfer Station Video Surveillance System%以网络球机为载体的换热站视频监控系统

    Institute of Scientific and Technical Information of China (English)

    李鹏飞; 史胜军

    2014-01-01

    随着科技的快速发展和供热行业的迅速进步,无人值守换热站已逐渐进入人们的视野;随着热网集中控制系统的日渐普及,热网的安全防盗、安全运行也成为人们关注的问题。为了使换热站监控系统更加完善、更加合理、更加先进、更加安全,设计了以网络球机为载体的换热站视频监控系统。该系统以网络球机为主要视频设备,采用VPN有线宽带网络将视频数据传至热力公司监控中心,通过网络视频录像机 NVR 录像,实现对换热站现场的监控,使热网的集中监控系统更加完善、更加安全可靠。%With the rapid advancement of technology and the rapid development of the industry of heating, heat transfer station unattended gradually coming into view;centralized control system with heating network growing popularity, heating network security, security, security operation has become people concerned about the problem. To make the heat transfer station monitoring system more perfect, more rational, more advanced, more secure, web-ball machine is designed as a carrier of heat transfer station video surveillance system. The system is web-ball machine as the primary video device, wired broadband network using VPN data is transmitted to the heating company video monitoring center through a network video recorder NVR recording, to achieve the heat transfer station site monitoring, thermal network centralized monitoring system more perfect, more secure and reliable.

  4. Probe Measurements of Ash Deposit Formation Rate and Shedding in a Biomass Suspension-Fired boiler

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming;

    The aim of this study was to investigate ash deposit formation rate, heat uptake reduction and deposit removal by using advanced online ash deposition and sootblowing probes in a 350 MWth suspension-fired boiler, utilizing wood and straw pellets as fuel. The influence of fuel type (straw share...

  5. 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.

  6. Ash formation, deposition, corrosion, and erosion in conventional boilers

    Energy Technology Data Exchange (ETDEWEB)

    Benson, S.A.; Jones, M.L. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-01

    The inorganic components (ash-forming species) associated with coals significantly affect boiler design, efficiency of operation, and lifetimes of boiler parts. During combustion in conventional pulverized fuel boilers, the inorganic components are transformed into inorganic gases, liquids, and solids. This partitioning depends upon the association of the inorganic components in the coal and combustion conditions. The inorganic components are associated as mineral grains and as organically associated elements, and these associations of inorganic components in the fuel directly influence their fate upon combustion. Combustion conditions, such as temperature and atmosphere, influence the volatility and the interaction of inorganic components during combustion and gas cooling, which influences the state and size composition distribution of the particulate and condensed ash species. The intermediate species are transported with the bulk gas flow through the combustion systems, during which time the gases and entrained ash are cooled. Deposition, corrosion, and erosion occur when the ash intermediate species are transported to the heat-transfer surface, react with the surface, accumulate, sinter, and develop strength. Research over the past decade has significantly advanced understanding of ash formation, deposition, corrosion, and erosion mechanisms. Many of the advances in understanding and predicting ash-related issues can be attributed to advanced analytical methods to determine the inorganic composition of fuels and the resulting ash materials. These new analytical techniques have been the key to elucidation of the mechanisms of ash formation and deposition. This information has been used to develop algorithms and computer models to predict the effects of ash on combustion system performance.

  7. The Future Resources for Eco-building Materials: II.Fly Ash and Coal Waste

    Institute of Scientific and Technical Information of China (English)

    LI Hui; XU Delong

    2009-01-01

    To use fly ash and coal waste effectively,the current technologies for reprocessing and recycling these wastes into eco-building materials were reviewed,such as utilizing fly ash as the component of fly ash cement and low heat cement after the processes of separation,removal of carbon remains and fine comminution,calcining coal waste into kaolin and meta-kaolin with suspension technology,and preparing clinkerless alkali-activated geopolymer materials with fly ash and meta-kaolin.

  8. Comparative studies on fly ash coated low heat rejection diesel engine on performance and emission characteristics fueled by rice bran and pongamia methyl ester and their blend with diesel

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed Musthafa, M.; Sivapirakasam, S.P.; Udayakumar, M. [National Institute of Technology, Tiruchchirappalli (India)

    2011-05-15

    In this study, for the first time, fly ash was used as a thermal barrier coating material in a diesel engine. The study consists of three phases. In first phase, biodiesel was prepared in a laboratory scale setup by single step base catalyzed transesterification method. In the second phase, engine combustion chamber elements such as cylinder head, cylinder liner, valves and piston crown face were coated with fly ash, which is a thermal power plant waste, to a thickness of 200{mu}m by using plasma spray coating method. In third phase, experiments were carried out on fly ash coated single cylinder diesel engine fueled by methyl ester of rice bran, pongamia oil and its blend (20% by volume) with diesel. The test run was repeated on uncoated engine under the same running conditions and the results were compared. An increase in engine power and decrease in specific fuel consumption, as well as significant improvements in exhaust gas emissions (except NOx) were observed for all test fuels used in the fly ash coated engine compared with that of the uncoated engine.

  9. 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.

  10. 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.

  11. 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) ...

  12. Relation between silico-aluminous fly ash and its coal of origin

    Institute of Scientific and Technical Information of China (English)

    Jean-Charles Benezet; Pierre Adamiec; Ali Benhassaine

    2008-01-01

    Fly ashes are typical complex solids which incorporate at the same time intrinsic properties derived from the layers (various mineralogical and dimensional spectra) and major transformations generated during prior processing. To use fly ashes in various applications, it is necessary to characterise them completely. The first research to date carried out on silico-aluminous fly ashes in order to characterise them physically,morphologically, chemically and mineralogically, resulted in the recognition that they are relatively simple materials. In the present study, a silico-aluminous fly ash coming from the power station of Albi (France) was selected. Heat treatment at 450 and 1200 ~C together with coal simulated the treatment undergone by coal in the power station in order to mimic real coal residue. In conclusion, the diversity of the particles contained in fly ash could only be explained by the relation existing between the fly ash and its coal of origin.

  13. Electroremediation of straw and co-combustion ash under acidic conditions

    DEFF Research Database (Denmark)

    Lima, Ana T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2009-01-01

    Biomass, such as wood and straw, is currently used in EU as a renewable energy source for energy production and this application is expected to rise in coming years. Combined heat and power installations produce fly ash, which is considered hazardous waste. The fly ash management issue should...... be addressed before biomass combustion is considered a truly sustainable technology. The electrodialytic process is a remediation technique able to assist the management of fly ash. For this work, straw and co-combustion of wood ash are briefly characterized and their electrodialytic treatment is carried out...... similarities with wood ash alone. However, further characterization should be carried out before any comparison regarding applicable legislation. Under acidic conditions, the electrodialytic treatment was not effective for the co-combustion wood ash. The heavy metals appeared in the least soluble fraction...

  14. 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

  15. Refrigerants and heat carrier fluids on a betain basis. A natural solution for preventing environmental, toxicity and corrosion problems in heating and cooling systems; Kaelte- und Waermetraeger auf Betain-Basis. Natuerliche Loesung fuer Umwelt-, Toxizitaets- und Korrosionsprobleme in Heiz- und Kuehlsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Willems, B.P.M.; Jokinen, J.

    2004-05-01

    Toxic liquids and environmental hazards in buildings and industrial plants are accepted less than ever today. So far, technical problems prevented substitution of glycol-based heat carrier fluids by brines or vegetable oils. A new refrigerant on the basis of betain has overcome these problems. (orig.) [German] Fluessigkeitstoxizitaet und Umweltrisiken in Gebaeuden und Industrieanlagen werden immer weniger akzeptiert. Der Ersatz Glykol-basierter Waermetraeger durch Fluessigkeiten auf Salz-Basis oder durch Pflanzenoel scheiterte bislang an technischen Schwierigkeiten. Ein neuerer Kaeltetraeger auf Betain-Basis hat diese Probleme ueberwunden. (orig.)

  16. Thermal treatment and vitrification of boiler ash from a municipal solid waste incinerator.

    Science.gov (United States)

    Yang, Y; Xiao, Y; Voncken, J H L; Wilson, N

    2008-06-15

    Boiler ash generated from municipal solid waste (MSW) incinerators is usually classified as hazardous materials and requires special disposal. In the present study, the boiler ash was characterized for the chemical compositions, morphology and microstructure. The thermal chemical behavior during ash heating was investigated with thermal balance. Vitrification of the ash was conducted at a temperature of 1400 degrees C in order to generate a stable silicate slag, and the formed slag was examined with chemical and mineralogical analyses. The effect of vitrification on the leaching characteristics of various elements in the ash was evaluated with acid leaching. The study shows that the boiler ash as a heterogeneous fine powder contains mainly silicate, carbonate, sulfates, chlorides, and residues of organic materials and heavy metal compounds. At elevated temperatures, the boiler ash goes through the initial moisture removal, volatilization, decomposition, sintering, melting, and slag formation. At 1400 degrees C a thin layer of salt melt and a homogeneous glassy slag was formed. The experimental results indicate that leaching values of the vitrified slag are significantly reduced compared to the original boiler ash, and the vitrification could be an interesting alternative for a safer disposal of the boiler ash. Ash compacting, e.g., pelletizing can reduce volatilization and weight loss by about 50%, and would be a good option for the feed preparation before vitrification.

  17. The Mineral Transformation of Huainan Coal Ashes in Reducing Atmospheres

    Institute of Scientific and Technical Information of China (English)

    LI Han-xu; Yoshihiko Ninomiya; DONG Zhong-bing; ZHANG Ming-xu

    2006-01-01

    By using the advanced instrumentation of a Computer Controlled Scanning Electron Microscope (CCSEM),X-ray diffraction (XRD) and X-ray fluorescence (XRF), the ash composition and the mineral components of six typical Huainan coals of different origins were studied. The transformation of mineral matter at high temperatures was tracked by XRD in reducing conditions. The quartz phase decreased sharply and the anorthite content tended to increase at first and then decreased with increasing temperatures. The formed mullite phase reached a maximum at 1250 ℃ but showed a tendency of slow decline when the temperature was over 1250 ℃. The mullite formed in the heating process was the main reason of the high ash melting temperature of Huainan coals. Differences in peak intensity of mullite and anorthite reflected differences in phase concentration of the quenched slag fractions, which contributed to the differences in ash melting temperatures. The differences in the location of an amorphous hump maximum indicated differences of glass types which may affect ash melting temperatures. For Huainan coal samples with relatively high ash melting temperatures, the intensity of the diffraction lines for mullite under reducing condition is high while for the samples with relatively low ash melting temperature the intensity for anorthite is high.

  18. Analog-experiment analysis of ash-deposition monitoring model of boiler economizers in power plants

    Institute of Scientific and Technical Information of China (English)

    CHENG Wei-liang; XIA Guo-dong; XU Shou-chen

    2005-01-01

    Ash deposition is a form of particulate fouling, and appears usually in boiler economizers. The ash deposition increases capital expenditure, energy input and maintenance costs. An analog experiment for monitoring ash deposition was performed from the analogous objective of a 410 t/h boiler economizer to verify the rationality and reliability of the ash-deposition-monitoring model presented in order to increase the security and economy in economizer running. The analog experiment platform is a tube-shell exchanger that conforms well to the conditions of a self-modeling area. The analog flue gas in the shell side is the heated air mixed with ash,and in the tube side the fluid is water heated by the flue gas. The fluid state in the water side and the flue gas side follows the second self-modeling area. A 4-factor-3 level orthogonal table was used to schedule 9 operation conditions of orthogonal experiment, with the 4 factors being heat power, flue gas velocity, ashes grain diameter and adding ashes quantity while the three levels are different values due to different position classes in every factor. The ash deposition thermal resistances is calculated by the model with the measure parameters of temperature and pressure drop. It shows that the values of the ash deposition thermal resistances gradually increase up to a stable state. And the experimental results are reliable by F testing method at α = 0. 001. Therefore, the model can be applied in online monitoring of ash deposition in a boiler economizers in power plants and provides scientific decision on ash deposition prediction and sootblowing.

  19. 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

  20. 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).

  1. Evaluation and Treatment of Coal Fly Ash for Adsorption Application

    Directory of Open Access Journals (Sweden)

    Samson Oluwaseyi BADA

    Full Text Available Many researchers had investigated fly ash as an adsorbent for the uptake of organic compounds from petrochemical waste effluents. The availability, inexpensive and its adsorption characteristic had made it an alternative media for the removal of organic compounds from aqueous solution. The physical property of South African Coal Fly Ash (SACFA was investigated to determine its adsorption capability and how it can be improved. Chemical treatment using 1M HCl solution in the ratio of (1 g fly ash to (2 ml of acid was used and compared with untreated heat-treated samples. The chemically treated fly ash has a higher specific surface area of 5.4116 m2/g than the heat-treated fly ash with 2.9969 m2/g. More attention had to be given to the utilization of SACFA for the treatment of wastewaters containing organic compounds through the application of Liquid phase adsorption process that was considered as an inexpensive and environmentally friendly technology.

  2. 利用垃圾焚烧飞灰制备硫铝酸盐水泥及其水化放热特征%Sulphoaluminate Cement Prepared with Municipal Solid Waste Incineration Fly Ash and Its Hydration Heat Evolution Characteristics

    Institute of Scientific and Technical Information of China (English)

    吴凯; 施惠生; 郭晓潞

    2011-01-01

    Municipal solid waste incineration (MSWI) fly ash was used as a raw material for calcining experiments of sulphoaluminate cement clinker in lab-scale. The effects of MSWI fly ash and alkalinity modulus on the formation of phases in the clinker were investigated. The morphology of the fired clinker was determined. The effect of gypsum on the mechanical properties of prepared cement and its characteristics of hydration heat evolution was analyzed. The results show that the desirable sulphoaluminate cement clinker can be fired by controlling the compositional parameters like alkalinity modulus (Cm) as 1.00-1.05, alumina-sulfur ratio P=2.5, and alumina-silica ratio n = 3, and the addition of MSWI fly ash into the raw mixture should not be greater than 30%. A sulphoaluminate cement can be prepared by adding the excessive amount of 5%-10% (mass fraction) gypsum to the clinkers. There existes a hydration heat evolution difference between sulphoaluminate cement prepared with MSWI fly ash and the common raw mixes.%以城市垃圾焚烧飞灰为主要原料,在实验室电炉里成功烧成了硫铝酸盐水泥熟料.分析了焚烧飞灰掺量、碱度对熟料烧成的影响,研究了烧成熟料的形貌、化学组成,以及掺加一定量的无水石膏配制的硫铝酸盐水泥物理性能及其水化放热特征.结果表明:以焚烧飞灰为主要原料可以煅烧得到理想的硫铝酸盐水泥熟料;生料配比中焚烧飞灰掺量不宜超过30%,所采用率值应控制为碱度Cm=1.00~1.05、铝硫比P=2.5和铝硅比n=3.无水石膏掺量町根据实际需要,在5%~10%(质量分数)范围内进行调节,均能配制出物理性能优异的水泥.利用焚烧飞灰煅烧的硫铝酸盐水泥水化放热曲线与以普通原料煅烧的水泥之间存在较大差异.

  3. 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.

  4. 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.

  5. Correction: Long, H. et al. More Wind Power Integration with Adjusted Energy Carriers for Space Heating in Northern China. Energies 2012, 5, 3279-3294.

    Directory of Open Access Journals (Sweden)

    Li Guo

    2012-11-01

    Full Text Available In the original version of the article published in Energies [1], insufficient acknowledgement was given for the contributors Mr. Li Guo and Prof. Kai Wu in Xi’an Jiaotong University. The main work was completed by the research group in Xi’an Jiaotong University led by Prof. Kai Wu.  Mr. Li Guo was his master student who gave a lot of efforts in the measurement of daily loads of heating and electricity in different families, and his data was used in Section 2.1. Prof. Kai Wu was involved in the whole work; he put forward the basic idea, made the research plan and participated in the detailed discussion about the algorithm for calculation. [...

  6. 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.

  7. Fly ash quality and utilization

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-01

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

  8. 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...

  9. Detecting Volcanic Ash Plumes with GNSS Signals

    Science.gov (United States)

    Rainville, N.; Larson, K. M.; Palo, S. E.; Mattia, M.; Rossi, M.; Coltelli, M.; Roesler, C.; Fee, D.

    2016-12-01

    Global Navigation Satellite Systems (GNSS) receivers are commonly placed near volcanic sites to measure ground deformation. In addition to the carrier phase data used to measure ground position, these receivers also record Signal to Noise ratio (SNR) data. Larson (2013) showed that attenuations in SNR data strongly correlate with ash emissions at a series of eruptions of Redoubt Volcano. This finding has been confirmed at eruptions for Tongariro, Mt Etna, Mt Shindake, and Sakurajima. In each of these detections, very expensive geodetic quality GNSS receivers were used. If low-cost GNSS instruments could be used instead, a networked array could be deployed and optimized for plume detection and tomography. The outputs of this sensor array could then be used by both local volcanic observatories and Volcano Ash Advisory Centers. Here we will describe progress in developing such an array. The sensors we are working with are intended for navigation use, and thus lack the supporting power and communications equipment necessary for a networked system. Reliably providing those features is major challenge for the overall sensor design. We have built prototypes of our Volcano Ash Plume Receiver (VAPR), with solar panels, lithium-ion batteries and onboard data storage for preliminary testing. We will present results of our field tests of both receivers and antennas. A second critical need for our array is a reliable detection algorithm. We have tested our algorithm on data from recent eruptions and have incorporated the noise characteristics of the low-cost GNSS receiver. We have also developed a simulation capability so that the receivers can be deployed to optimize vent crossing GNSS signals.

  10. 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 ...

  11. 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...

  12. Degradable Cross-Linked Nanoassemblies as Drug Carriers for Heat Shock Protein 90 Inhibitor 17-N-Allylamino-17-demethoxy-geldanamycin.

    Science.gov (United States)

    Ponta, Andrei; Akter, Shanjida; Bae, Younsoo

    2011-09-26

    Cross-linked nanoassemblies (CNAs) with a degradable core were prepared for sustained release of 17-N-allylamino-17-demethoxygeldanamycin (17-AAG), a potent inhibitor of heat shock protein 90 (HSP90). The particle size of CNAs ranged between 100 and 250 nm, which changed depending on the cross-linking yields and drug entrapment method. CNAs with a 1% cross-linking yield entrapped 17-AAG in aqueous solutions, yet degraded in 3 hrs. CNAs entrapped 5.2 weight% of 17-AAG as the cross-linking yield increased to 10%, retaining more than 80% of particles for 24 hrs. CNAs with drugs entrapped after the cross-linking reactions were 100 nm and remained stable in both pH 7.4 and 5.0, corresponding to the physiological, tumoral, and intracellular environments. Drug was completely released from CNAs in 48 hrs, which would potentially maximize drug delivery and release efficiency within tumor tissues. Drug release patterns were not negatively affected by changing the cross-linking yields of CNAs. CNAs entrapping 17-AAG suppressed the growth of human non-small cell lung cancer A549 cells as equally effective as free drugs. The results demonstrated that CNAs would be a promising formulation that can be used in aqueous solutions for controlled delivery and release of 17-AAG.

  13. Degradable Cross-Linked Nanoassemblies as Drug Carriers for Heat Shock Protein 90 Inhibitor 17-N-Allylamino-17-demethoxy-geldanamycin

    Directory of Open Access Journals (Sweden)

    Andrei Ponta

    2011-09-01

    Full Text Available Cross-linked nanoassemblies (CNAs with a degradable core were prepared for sustained release of 17-N-allylamino-17-demethoxygeldanamycin (17-AAG, a potent inhibitor of heat shock protein 90 (HSP90. The particle size of CNAs ranged between 100 and 250 nm, which changed depending on the cross-linking yields and drug entrapment method. CNAs with a 1% cross-linking yield entrapped 17-AAG in aqueous solutions, yet degraded in 3 hrs. CNAs entrapped 5.2 weight% of 17-AAG as the cross-linking yield increased to 10%, retaining more than 80% of particles for 24 hrs. CNAs with drugs entrapped after the cross-linking reactions were 100 nm and remained stable in both pH 7.4 and 5.0, corresponding to the physiological, tumoral, and intracellular environments. Drug was completely released from CNAs in 48 hrs, which would potentially maximize drug delivery and release efficiency within tumor tissues. Drug release patterns were not negatively affected by changing the cross-linking yields of CNAs. CNAs entrapping 17-AAG suppressed the growth of human non-small cell lung cancer A549 cells as equally effective as free drugs. The results demonstrated that CNAs would be a promising formulation that can be used in aqueous solutions for controlled delivery and release of 17-AAG.

  14. Heating of carriers as controlled by the combined interactions with acoustic and piezoelectric phonons in degenerate III-V semiconductors at low lattice temperature

    Science.gov (United States)

    Bhattacharya, D. P.; Das, J.; Basu, A.; Das, B.

    2017-09-01

    In compound semiconductors which lack inversion symmetry, the combined interaction of the electrons with both acoustic and piezoelectric phonons is dominant at low lattice temperatures ( 20 K). The field dependence of the effective electron temperature under these conditions, has been calculated by solving the modified energy balance equation that takes due account of the degeneracy. The traditionally used heated Fermi-Dirac (F.D.) function for the non-equilibrium distribution function is approximated by some well tested model distribution. This makes it possible to carry out the integrations quite easily and, thus to obtain some more realistic results in a closed form, without taking recourse to any oversimplified approximations. The numerical results that follow for InSb, InAs and GaN, from the present analysis, are then compared with the available theoretical and experimental data. The degeneracy and the piezoelectric interaction, both are seen to bring about significant changes in the electron temperature characteristics. The scope for further refinement is discussed.

  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. Coal ash fusion temperatures - new characterization techniques and implications for slagging and fouling

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-09-01

    The ash fusion test (AFT) is the accepted test for the propensity of coal ash to slag in the furnace. The well-documented shortcomings of this technique for estimating the fusion temperature of coal ash are its subjective nature and poor accuracy. Alternative measurements based on the shrinkage and electrical conductivity of heating samples are therefore examined here with laboratory ash prepared at about 800{degree}C in crucibles, as well as combustion ash samples from power stations. Sensitive shrinkage measurements indicate temperatures of rapid change which correspond to the formation of liquid phases that can be identified on ternary phase diagrams. The existence and extent of formation of these phases, as quantified by the magnitude of `peaks` in the test, provide alternative ash fusion temperatures. The peaks from laboratory ashes and corresponding combustion ashes derived from the same coals show clear differences which may be related to the evaporation of potassium during combustion and the reactions of the mineral residues to form combustion ash. A preliminary evaluation of data from nine power stations indicates that shrinkage measurements can provide an alternative approach to characterizing slagging. 15 refs., 9 figs., 2 tabs.

  17. “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.

  18. Influence of Coal Blending on Ash Fusibility in Reducing Atmosphere

    Directory of Open Access Journals (Sweden)

    Mingke Shen

    2015-05-01

    Full Text Available Coal blending is an effective way to organize and control coal ash fusibility to meet different requirements of Coal-fired power plants. This study investigates three different eutectic processes and explains the mechanism of how coal blending affects ash fusibility. The blended ashes were prepared by hand-mixing two raw coal ashes at five blending ratios, G:D = 10:90 (G10D90, G:D= 20:80 (G20D80, G:D = 30:70 (G30D70, G:D = 40:60 (G40D60, and G:D = 50:50 (G50D50. The samples were heated at 900 °C, 1000 °C, 1100 °C, 1200 °C, and 1300 °C in reducing atmosphere. XRD and SEM/EDX were used to identify mineral transformations and eutectic processes. The eutectic processes were finally simulated with FactSage. Results show that the fusion temperatures of the blended ashes initially decrease and then increase with the blending ratio, a trend that is typical of eutectic melting. Eutectic phenomena are observed in D100, G10D90, and G30D70 in different degrees, which do not appear in G100 and G50D50 for the lack of eutectic reactants. The main eutectic reactants are gehlenite, magnetite, merwinite, and diopside. The FactSage simulation results show that the content discrepancy of merwinite and diopside in the ashes causes the inconsistent eutectic temperatures and eutectic degrees, in turn decrease the fusion temperature of the blended ash and then increase them with the blending ratio.

  19. Prevalence of breast and colorectal cancer in Ashkenazi Jewish carriers of Fanconi anemia and Bloom syndrome.

    Science.gov (United States)

    Baris, Hagit N; Kedar, Inbal; Halpern, Gabrielle J; Shohat, Tamy; Magal, Nurit; Ludman, Mark D; Shohat, Mordechai

    2007-12-01

    Fanconi anemia complementation group C and Bloom syndrome, rare autosomal recessive disorders marked by chromosome instability, are especially prevalent in the Ashkenazi* Jewish community. A single predominant mutation for each has been reported in Ahshkenazi Jews: c.711+4A-->T (IVS4 +4 A-->T) in FACC and BLM(Ash) in Bloom syndrome. Individuals affected by either of these syndromes are characterized by susceptibility for developing malignancies, and we questioned whether heterozygote carriers have a similarly increased risk. To estimate the cancer rate among FACC and BLM(Ash) carriers and their families over three previous generations in unselected Ashkenazi Jewish individuals. We studied 42 FACC carriers, 28 BLM(Ash) carriers and 43 controls. The control subjects were Ashkenazi Jews participating in our prenatal genetic screening program who tested negative for FACC and BLM(Ash). All subjects filled out a questionnaire regarding their own and a three-generation family history of cancer. The prevalence rates of cancer among relatives of FACC, BLM(Ash) and controls were computed and compared using the chi-square test. In 463 relatives of FACC carriers, 45 malignancies were reported (9.7%) including 10 breast (2.2%) and 13 colon cancers (2.8%). Among 326 relatives of BLM(Ash) carriers there were 30 malignancies (9.2%) including 7 breast (2.1%) and 4 colon cancers (1.2%). Controls consisted of 503 family members with 63 reported malignancies (12.5%) including 11 breast (2.2%) and 11 colon cancers (2.2%). We found no significantly increased prevalence of malignancies among carriers in at least three generations compared to the controls.

  20. Quantification of Ash Deposit Build-up and Removal in a Straw and Wood Suspension-Fired Boiler

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming

    2011-01-01

    The aim of this study was to investigate ash deposit formation rate, heat uptake reduction and deposit removal by using advanced online ash deposition and sootblowing probes in a 350 MWth suspension­fired boiler, utilizing wood and straw pellets as fuel. The influence of fuel type (straw share in...

  1. 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...

  2. Characteristics of the ultrafine component of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    M.R. Jones; A. McCarthy; A.P.P.G. Booth [University of Dundee, Dundee (United Kingdom). Concrete Technology Unit, Division of Civil Engineering

    2006-11-15

    Post-production processing of fly ash (FA) is an important issue for its use in concrete. Given (i) the need for environmental protection, (ii) the measures being applied on coal-fired power stations to reduce acidic gas emissions and (iii) the effect these have had on fly ash quality, there is a need to consider efficient post-production processing to enhance fly ash characteristics. This is particularly important for fly ash used as a cement in concrete production, since the additional residual carbon content and decreased fineness significantly affect its quality. This paper details the material characteristics of an ultrafine, low-lime fly ash (UF-FA), produced, in this case, by processing a coarse FA (referred to as parent FA) from a bituminous coal-fired power station via air-cyclonic separation. The UF-FA is shown to have much improved material characteristics compared to the parent FA in terms of morphology, mineralogy and chemical composition. Further results are presented on the effect of UF-FA on the properties of cementitious systems. Improved consistence and compressive strengths of combined Portland cement (PC) and UF-FA mortars were observed, whilst enhanced PC hydration and a high degree of FA reactivity were concluded from heat of hydration measurements and calcium hydroxide contents of pastes. 20 refs., 10 figs., 1 tab.

  3. The utilisation of fly ash in CO2 mineral carbonation

    Directory of Open Access Journals (Sweden)

    Jaschik Jolanta

    2016-03-01

    Full Text Available The fixation of CO2 in the form of inorganic carbonates, also known as mineral carbonation, is an interesting option for the removal of carbon dioxide from various gas streams. The captured CO2 is reacted with metal-oxide bearing materials, usually naturally occurring minerals. The alkaline industrial waste, such as fly ash can also be considered as a source of calcium or magnesium. In the present study the solubility of fly ash from conventional pulverised hard coal fired boilers, with and without desulphurisation products, and fly ash from lignite fluidised bed combustion, generated by Polish power stations was analysed. The principal objective was to assess the potential of fly ash used as a reactant in the process of mineral carbonation. Experiments were done in a 1 dm3 reactor equipped with a heating jacket and a stirrer. The rate of dissolution in water and in acid solutions was measured at various temperatures (20 - 80ºC, waste-to-solvent ratios (1:100 - 1:4 and stirrer speeds (300 - 1100 min-1. Results clearly show that fluidised lignite fly ash has the highest potential for carbonation due to its high content of free CaO and fast kinetics of dissolution, and can be employed in mineral carbonation of CO2.

  4. ADVANCED POWER SYSTEMS ASH BEHAVIOR IN POWER SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    ZYGARLICKE, CHRISTOPHER J; MCCOLLOR, DONALD P; KAY, JOHN P; SWANSON, MICHAEL L

    1998-09-01

    The overall goal of this initiative is to develop fundamental knowledge of ash behavior in power systems for the purpose of increasing power production efficiency, reducing operation and maintenance costs, and reducing greenhouse gas emissions into the atmosphere. The specific objectives of this initiative focus primarily on ash behavior related to advanced power systems and include the following: Determine the current status of the fundamental ash interactions and deposition formation mechanisms as already reported through previous or ongoing projects at the EERC or in the literature. Determine sintering mechanisms for temperatures and particle compositions that are less well known and remain for the most part undetermined. Identify the relationship between the temperature of critical viscosity (Tcv ) as measured in a viscometer and the crystallization occurring in the melt. Perform a literature search on the use of heated-stage microscopy (HSM) for examining in situ ash-sintering phenomena and then validate the use of HSM in the determination of viscosity in spherical ash particles. Ascertain the formation and stability of specific mineral or amorphous phases in deposits typical of advanced power systems. Evaluate corrosion for alloys being used in supercritical combustion systems.

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

    Directory of Open Access Journals (Sweden)

    Tatyana Aleksandrova

    2017-07-01

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

  6. 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.

  7. Effect of fly ash deposition on photosynthesis, growth and yield of rice.

    Science.gov (United States)

    Raja, R; Nayak, A K; Rao, K S; Puree, Chandrika; Shahid, Mohammad; Panda, B B; Kumar, Anjani; Tripathi, R; Bhattacharyya, P; Baig, M J; Lal, B; Mohanty, Sangita; Gautam, Priyanka

    2014-07-01

    An experiment was conducted to assess the effect of fly ash deposition without and with (0.25, 0.50, 1.0 and 1.5 g m(-2 )day(-1)) foliar dusting on the photosynthesis, stomatal conductance, transpiration, leaf temperature, albedo and productivity of rice. Dusting of 0.5 g m(-2 )day(-1) fly ash and above significantly reduced the photosynthesis, stomatal conductance, transpiration and albedo. Panicle initiation and flowering stages were more influenced by the fly ash deposition as compared to active tillering stage. At higher rates of fly ash deposition, all growth and yield parameters were significantly influenced due to increased heat load and reduced intercellular CO2 concentration. A significant reduction of 12.3, 15.7 and 20.2 % in grain yield was recorded over control when fly ash was dusted at 0.5, 1.0 and 1.5 g m(-2 )day(-1), respectively.

  8. Hot-Carrier Seebeck Effect: Diffusion and Remote Detection of Hot Carriers in Graphene

    Science.gov (United States)

    Sierra, Juan F.; Neumann, Ingmar; Costache, Marius V.; Valenzuela, Sergio O.

    2015-06-01

    We investigate hot carrier propagation across graphene using an electrical nonlocal injection/detection method. The device consists of a monolayer graphene flake contacted by multiple metal leads. Using two remote leads for electrical heating, we generate a carrier temperature gradient that results in a measurable thermoelectric voltage VNL across the remaining (detector) leads. Due to the nonlocal character of the measurement, VNL is exclusively due to the Seebeck effect. Remarkably, a departure from the ordinary relationship between Joule power P and VNL, VNL ~ P, becomes readily apparent at low temperatures, representing a fingerprint of hot-carrier dominated thermoelectricity. By studying VNL as a function of bias, we directly determine the carrier temperature and the characteristic cooling length for hot-carrier propagation, which are key parameters for a variety of new applications that rely on hot-carrier transport.

  9. Hot-Carrier Seebeck Effect: Diffusion and Remote Detection of Hot Carriers in Graphene.

    Science.gov (United States)

    Sierra, Juan F; Neumann, Ingmar; Costache, Marius V; Valenzuela, Sergio O

    2015-06-10

    We investigate hot carrier propagation across graphene using an electrical nonlocal injection/detection method. The device consists of a monolayer graphene flake contacted by multiple metal leads. Using two remote leads for electrical heating, we generate a carrier temperature gradient that results in a measurable thermoelectric voltage V(NL) across the remaining (detector) leads. Due to the nonlocal character of the measurement, V(NL) is exclusively due to the Seebeck effect. Remarkably, a departure from the ordinary relationship between Joule power P and V(NL), V(NL) ∼ P, becomes readily apparent at low temperatures, representing a fingerprint of hot-carrier dominated thermoelectricity. By studying V(NL) as a function of bias, we directly determine the carrier temperature and the characteristic cooling length for hot-carrier propagation, which are key parameters for a variety of new applications that rely on hot-carrier transport.

  10. Adsorption of formaldehyde in air by modified fly ash%改性粉煤灰对空气中甲醛的吸附研究

    Institute of Scientific and Technical Information of China (English)

    蔡志红; 李彩亭; 文青波; 路培; 李珊红; 曾光明

    2011-01-01

    以粉煤灰为主要材料,使用3种方法分别对粉煤灰进行改性,研究不同条件下改性粉煤灰对空气中甲醛的吸附特性和去除效果,并探讨粉煤灰对甲醛的吸附和脱附机理.研究结果表明3种改性粉煤灰对甲醛的吸附能力由高到低为:ZnCl2改性粉煤灰,热处理粉煤灰,水洗粉煤灰;在甲醛初始质量浓度为0.41 mg/m3,改性粉煤灰用量为1.0 g,温度为25℃的情况下,ZnCl2改性粉煤灰对甲醛最大去除率达70.48%,去除效果与煤基活性炭的相当(最大去除率为68.96%),远超过了未改性的粉煤灰的最大去除率(30.71%); ZnCl2改性的粉煤灰重新活化后,可重复使用,5次再生实验后的吸附率仍达60.02%.%Using fly ash as a carrier, three kinds of methods were used to modify the nature of fly ash in order to study adsorption characteristics and the removal of formaldehyde in air under different experimental conditions. The mechanism of fly ash to adsorption and desorption of formaldehyde was also discussed. The results show that the adsorptive capacities of formaldehyde by modified fly ash from strong to weak are as follows: ZnCl2-modified fly ash, heat-treatment fly ash, water-treatment fly ash. When dosage of ZnCl2-modified fly ash is 1.0 g, the original concentration of formaldehyde is 0.41 mg/m3 and the temperature is 25℃, the maximum removal rate can reach 70.48%, which is much higher than that of non-modified fly ash (30.71%), and as much as that of coal-based activated carbon (68.96%). ZnCl2-modtfied fly ash can be effectually reused after reactivated, and the removal rate of formaldehyde remains up to 60.02% after five regenerations.

  11. Treatment and recycling of incinerated ash using thermal plasma technology.

    Science.gov (United States)

    Cheng, T W; Chu, J P; Tzeng, C C; Chen, Y S

    2002-01-01

    To treat incinerated ash is an important issue in Taiwan. Incinerated ashes contain a considerable amount of hazardous materials such as dioxins and heavy metals. If these hazardous materials are improperly treated or disposed of, they shall cause detrimental secondary contamination. Thermal plasma vitrification is a robust technology to treat and recycle the ash residues. Under the high temperature plasma environment, incinerated ashes are vitrified into benign slag with large volume reduction and extreme detoxification. Several one-step heat treatment processes are carried out at four temperatures (i.e. 850, 950, 1,050 and 1,150 degrees C) to obtain various "microstructure materials". The major phase to form these materials is a solid solution of gehlenite (Ca2Al2SiO7) and åkermanite (Ca2MgSi2O7) belonging to the melilite group. The physical and mechanical properties of the microstructure materials are improved by using one-step post-heat treatment process after plasma vitrification. These microstructure materials with good quality have great potential to serve as a viable alternative for construction applications.

  12. 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...

  13. 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...

  14. Investigation on the fly ash thermal treatment on the performance of Lithium Ferriphosphate (LiFePO{sub 4}) battery

    Energy Technology Data Exchange (ETDEWEB)

    Febiolita, Bella; Khoirunnissak, Dewi; Purwanto, Agus, E-mail: aguspurw@gmail.com [Research Group of Battery & Advanced Material, Department of Chemical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A Kentingan, Surakarta Indonesia 57126 (Indonesia)

    2016-02-08

    Addition of the fly ash can be used to improve the capacity of LiFePO{sub 4} battery. Fly ash was added in Acethylene Black (AB) as 2% of the total weight of Acetylene Black (AB). The effects of temperature variation and fly ash characteristics were analyzed. Fly ash was prepared by heating at 50, 100, 150, and 250°C in muffle furnace for 5 hours and passed in 200 mesh screen prior to mixing it with other compounds. Lithium Ferriphospat (LiFePO{sub 4}), fly ash, Acethylene Black (AB), Polyvinylidene Fluoride (PVDF) as a binder and N-methyl-2-pyrrolidone (NMP) as a solvent were mixed to be slurry. The slurry were coated, dried and hot pressed to make a cathode film. The performance of battery lithium was examined by eight channel battery analyzer. The composition of the fly ash was examined by X-ray fluorescence spectrometry (XRF) and Fourier Tansform Infrared Spectroscopy (FTIR). The excellent performance was shown in the fly ash addition which were treated by heating at 150°C. The capacity of fly ash added LiFePO{sub 4} battery is 94.373 mAh/g, which is higher than that of without fly ash addition, i.e. 67.998 mAh/g.

  15. Improvement, characterization and use of waste corn cob ash in cement-based materials

    Science.gov (United States)

    Suwanmaneechot, P.; Nochaiya, T.; Julphunthong, P.

    2015-12-01

    This work investigates the development of waste corn cob ash as supplementary cement replacement materials. The study focused on the effects of heat treatment on chemical composition, physical properties and engineering properties of corn cob ash. The results suggest corn cob ash that was heat treated at 600°C for 4 h shows percentage of SiO2 + Al2O3 + Fe2O3 around 72%, which can be classified as Class N calcined natural pozzolan, as prescribed by ASTM C618. The X-ray diffraction patterns indicated that the amorphous silica phase increased with increasing calcining temperatures. The water requirement, initial setting time and final setting time of specimens increased with increasing replacement percentage of raw or treated corn cob ash. The morta cubes which used 20% of treated corn cob ash replaced cement showed 103% of the 28 days compressive strength as compared to reference samples. The corn cob ash that was treated at 600°C for 4 h samples shows slightly higher effectiveness for improving the splitting tensile strength and compressive strength of concrete when compared to the untreated corn cob ash.

  16. Biomass ash - bed material interactions leading to agglomeration in fluidised bed combustion and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Visser, H.J.M.; Hofmans, H.; Huijnen, R.; Kastelein, R.; Kiel, J.H.A. [ECN Biomass, Petten (Netherlands)

    2000-07-01

    The present study has been aimed at improving the fundamental understanding of mechanisms underlying agglomeration and defluidisation in fluidised bed combustion and gasification of biomass and waste. To this purpose dedicated lab-scale static heating and fluidisation experiments have been conducted with carefully selected and prepared ashes and bed materials, viz. straw ash/sand and willow ash/sand mixtures, mullite subjected to straw gasification and artificially coated mullite. The main conclusion is that ash/bed material interaction processes are very important and often determine the bed agglomeration and defluidisation tendency. In the static heating experiments with both ash/sand mixtures, partial melting-segregation of ash components and dissolution/reaction with the bed material are processes that determine the melt composition. This melt composition and behaviour can deviate considerably form expectations based on ash-only data. Artificially coated bed materials prove to be very useful for systematic studies on the influence of coating composition and thickness on agglomeration tendency. For the coated mullite samples, different stages in the defluidisation process are identified and the influence of coating properties (thickness, composition, morphology) and operating parameters is elucidated. The behaviour of the mullite appears to be dominated by a remnant glass phase. On the one hand, this glass phase accounts for an alkali-getter capability, while on the other hand it is mainly responsible for agglomeration at temperatures {>=} 800C. 3 refs.

  17. Amenability to dry processing of high ash thermal coal using a pneumatic table

    Institute of Scientific and Technical Information of China (English)

    Dey Shobhana; Gangadhar B.; Gopalkrishna S.J.

    2015-01-01

    High ash thermal coal from India was used to conduct the dry processing of fine coal using a pneumatic table to evolve a techno-economically novel technique. The fine as-received sample having 55.2%ash was subjected to washability studies at variant densities from 1.4 to 2.2 to assess the amenability to separa-tion. The experiments were conducted using a central composite design for assessing the interactive effects of the variable parameters of a pneumatic table on the product yield and ash content. The perfor-mance of the pneumatic table was analyzed in terms of clean coal yield, recovery of combustibles, separation efficiency (Esp) and useful heat value of clean coal. The combustibles of clean coal obtained through a single stage operation at 35% and 38.7% ash were 40% and 63% respectively. However, the two stage processing was more effective in reducing the ash content in the clean coal. The rougher con-centrate generated at higher ash level was subsequently processed in different conditions at 35% ash level, and 58%combustibles could be recovered. Hence, two stage processing increases the combustibles by 18 units and the useful heat value of clean coal increases from 1190 kcal/kg to 3750 kcal/kg.

  18. Modern power station practice mechanical boilers, fuel-, and ash-handling plant

    CERN Document Server

    Sherry, A; Cruddace, AE

    2014-01-01

    Modern Power Station Practice, Second Edition, Volume 2: Mechanical (Boilers, Fuel-, and Ash-Handling Plant) focuses on the design, manufacture and operation of boiler units and fuel-and ash-handling plants.This book is organized into five main topics-furnace and combustion equipment, steam and water circuits, ancillary plant and fittings, dust extraction and draught plant, and fuel-and ash-handling plant.In these topics, this text specifically discusses the influence of nature of coal on choice of firing equipment; oil-burner arrangements, ignition and control; disposition of the heating surf

  19. Iron-containing phases in fly ashes from different combustion systems

    Directory of Open Access Journals (Sweden)

    Szumiata Tadeusz

    2015-03-01

    Full Text Available The investigations of iron-containing phases existing in fly ashes were performed using transmission Mössbauer spectrometry. The examined samples of fly ashes were collected from different coal combustion systems, that is, stoker-fired boiler in municipal heating plant and pulverized coal boiler in power plant. Several phases are identified in the samples: iron oxides, paramagnetic aluminosilicate glass with Fe3+ ions and Al2O4-type spinel with Fe2+ ions. It was pointed out that proportions of contents of phases strongly depend not only on the combustion temperature but also on the way of ash collection.

  20. Decolorization of a textile vat dye by adsorption on waste ash

    OpenAIRE

    MIODRAG ŠMELCEROVIĆ; DRAGAN ĐORĐEVIĆ; MILE NOVAKOVIĆ; MIRJANA MIZDRAKOVIĆ

    2010-01-01

    An adsorption process using cheap adsorbents could be described as a simple, selective and low cost alternative for the treatment of colored waste water compared to conventional physical and chemical processes. In this study the use of a natural waste adsorbent–ash was investigated for the removal of a textile vat dye Ostanthren blue GCD remaining after the dyeing of cotton textile. The ash obtained as a waste material during the burning of brown coal in the heating station of Leskovac (Serbi...

  1. 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...

  2. Standard procedure for the determination of ash-fusion behavior of biomass fuels; Standardisiertes Verfahren zur Bestimmung des thermischen Ascheverhaltens biogener Brennstoffe

    Energy Technology Data Exchange (ETDEWEB)

    Ottmann, M.; Karl, J. [Technische Univ. Muenchen, Garching bei Muenchen (Germany). Lehrstuhl Thermische Kraftanlagen; Hein, D.

    2004-07-01

    An important property of some bio fuels, particularly at combustion in fluidized bed reactors (FBC), is the very low deformation temperature of its ash. Whereas wood ash is melting at very high temperatures (approx. 1400 C to 1500 C) are ashes of grasses or residues of food industry melting at very low temperatures (<900 C). Low sintering and deformation temperatures cause coating and agglomerating of bed particles of the FBC and fouling of heat exchangers. In order to determinate relevant temperature ranges of different fuels these ashes are melted in laboratory experiments. In these experiments fuels will be burned and the ashes will be pressed to defined forms. Subsequently the ash corpus will be heated up. The change of its form will be watched via microscope and recorded. The procedure for the description of the ash-fusion behavior by ash fusion microscope is fixed in DIN 51730 'Determination of the ash fusion behavior'. This standard was developed for fossil solid fuels. With the last expenditure of this DIN in 1998 some new aspects came up regarding the attempt matrix, form of the sample, and also regarding the analysis procedure for the execution of the attempts. Likewise decisions were necessary regarding the type of ashing, the preparation of ash and the pressing power for the samples. A set of experiments was necessary, in order to place a meaningful, reproducible execution. (orig.)

  3. Some Aspects Concerning Convective Circulation Mode of Heat Transfer in Furnace to Wood Heat Treatment

    Directory of Open Access Journals (Sweden)

    Nadia Potoceanu

    2007-10-01

    Full Text Available The paper presented the most aspects of convective circulate mode of heat transfer : heat transfer through the boundary layer formed at the surface of the heat generator; heat transfer in the heat carrier and heat transfer through the boundary layer formed at the heated surface

  4. 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.

  5. Low temperature heating and high temperature cooling embedded water based surface heating and cooling systems

    CERN Document Server

    Babiak, Jan; Petras, Dusan

    2009-01-01

    This Guidebook describes the systems that use water as heat-carrier and when the heat exchange within the conditioned space is more than 50% radiant. Embedded systems insulated from the main building structure (floor, wall and ceiling) are used in all types of buildings and work with heat carriers at low temperatures for heating and relatively high temperature for cooling.

  6. Preparation of New Cementitious System using Fly Ash and Dehydrated Autoclaved Aerated Concrete

    Institute of Scientific and Technical Information of China (English)

    SHUI Zhonghe; LU Jianxin; TIAN Sufang; SHEN Peiliang; DING Sha

    2014-01-01

    We experimentally studied the interaction between pozzolanic material (fly ash) and dehydrated autoclaved aerated concrete (DAAC). The DAAC powder was obtained by grinding aerated concrete waste to particles finer than 75μm and was then heated to temperatures up to 900℃. New cementitious material was prepared by proportioning fly ash and DAAC, named as AF. X-ray diffraction (XRD) was employed to identify the crystalline phases of DAAC before and after rehydration. The hydration process of AF was analyzed by the heat of hydration and non-evaporable water content (Wn). The experimental results show that the highest reactivity of DAAC can be obtained by calcining the powder at 700℃and the dehydrated products are mainlyβ-C2S and CaO. The cumulative heat of hydration and Wn was found to be strongly dependent on the replacement level of fly ash, increasing the replacement level of fly ash lowered them in AF. The strength contribution rates on pozzolanic effect of fly ash in AF are always negative, showing a contrary tendency of that of cement-fly ash system.

  7. 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.

  8. 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

  9. 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...

  10. Heat Calculation of Borehole Heat Exchangers

    Directory of Open Access Journals (Sweden)

    S. Filatov

    2013-01-01

    Full Text Available The paper considers a heat calculation method of borehole heat exchangers (BHE which can be used for designing and optimization of their design values and included in a comprehensive mathematical model of heat supply system with a heat pump based on utilization of low-grade heat from the ground.The developed method of calculation is based on the reduction of the problem general solution pertaining to heat transfer in BHE with due account of heat transfer between top-down and bottom-up flows of heat carrier to the solution for a boundary condition of one kind on the borehole wall. Used the a method of electrothermal analogy has been used for a calculation of the thermal resistance and  the required shape factors for calculation of  a borehole filler thermal resistance have been obtained numerically. The paper presents results of heat calculation of various BHE designs in accordance with the proposed method.

  11. Ash in composting of source-separated catering waste.

    Science.gov (United States)

    Koivula, Niina; Räikkönen, Tarja; Urpilainen, Sari; Ranta, Jussi; Hänninen, Kari

    2004-07-01

    Our earlier experiments in small composters (220 l) indicated the favourable effect of ash from co-incineration of sorted dry waste on the composting of catering waste. The aim of this new study was to clarify further, at a scale of 10 m3, the feasibility of using similar ash as an additive in composting. Source-separated catering waste was mixed with bulking agent (peat and wood chips) and fuel ash from a small (4 MW) district heating power plant. Three compost mixes (CM) were obtained: CM I with 0%, CM II with 10% and CM III with 20 wt.% of fuel ash. These three different mixes were composted in a 10-m3 drum composter as three parallel experiments for 2 weeks each, from January to April 2000. After drum composting, masses were placed according to mixing proportions in separate curing piles. The catering waste fed to the drum was cold, sometimes icy. Even then the temperature rapidly increased to over 50 degrees C. In CM III, the temperature rose as high as 80 degrees C, and after the first week of composting the temperature was about 20 degrees C higher in the CMs II and III than in the CM I. It also improved the oxygen concentrations at the feeding end of the drum and obviously prevented the formation of H2S. No odour problems arose during the composting. Addition of ash increased the heavy metal contents of the composting masses, but the compost was suitable for cultivation or green area construction. Ash clearly decreased the loss of total nitrogen in a time span of 2 years. The lower amounts of nitrogen mean that the amounts applied per hectare can be greater than for normal composts. Measured by mineralization, the breaking down of the organic matter was more rapid in the CM III than in the CM I. Humic acid increased steadily during first 12 months composting, from the initial 39 mg/g organic matter to 115 and 137 mg/g in CMs II and III. Measured by temperature, mineralization and humification the addition of ash appeared to boost the composting. Ash had

  12. Wildfire Ash: Chemical Composition, Ash-Soil Interactions and Environmental Impacts

    Science.gov (United States)

    Brook, Anna; Hamzi, Seham; Wittenberg, Lea

    2015-04-01

    S., Morag H., 2013. The effect of wildfires on vegetation cover and dune activity in Australia's desert dunes: a multisensor analysis International Journal of Wildland Fire, vol. 21 (4), pp. 459-475. Lugassi R., Ben-Dor E., Eshel G., 2013. Reflectance spectroscopy of soils post-heating'Assessing thermal alterations in soil minerals. Geoderma, vol. 231, pp. 268-279. Pereira P., Úbeda X., Martin D., Mataix-Solera J., Guerrero C. 2011. Effects of a low prescribed fire in ash water soluble elements in a Cork Oak (Quercus suber) forest located in Northeast of Iberian Peninsula, Environmental Research, vol. 111(2), pp. 237-247. Shakesby R.A., 2011. Post-wildfire soil erosion in the Mediterranean: Review and future research directions Earth Science Reviews, vol. 105, pp. 71-100. Woods, S.W., Balfour, V.N. 2010. The effects of soil texture and ash thickness on the post-fire hydrological response from ash-covered soils, Journal of Hydrology, vol. 393, pp. 274-286.

  13. Current Methods to Detoxify Fly Ash from Waste Incineration

    Energy Technology Data Exchange (ETDEWEB)

    Hallgren, Christine; Stroemberg, Birgitta [TPS Termiska Processer AB, Nykoeping (Sweden)

    2004-07-01

    vitrification, electric arc and melting in a secondary combustion chamber by adding coke as a heating source (coke bed melting furnaces) or residual carbon in the fly ash (Rotary surface melting furnace) are the most common methods. In general, vitrification processes require a high-energy input and are therefore relatively cost intensive. Locking the hazardous components into the matrix by a stabilization/solidification with cement is a common alternative to decontamination. Mixing the fly ash with cement or asphalt is widely used for the reuse of fly ash from coal incineration, but it requires careful attention to any leaching of heavy metals if applied to fly ash from waste incineration. Studies by mixing fly ash with cement at concentrations from 5 to 70 % showed, that in most cases an additional pretreatment step, e.g. washing in HNO{sub 3} solution, is necessary to receive acceptable leaching behaviour and required properties as building material. Related European regulations are currently pending. On the other hand, the use of fly ash as filler for asphalt does not require any pretreatment and is already commonly applied in some countries such as the Netherlands as a well-established method. Solvent extraction methods such as acidic extraction (3R-process) or combined basic and acidic extraction (MR-process) are also designed to remove the contaminants. The effectiveness of these methods is only moderate and a further thermal treatment is required to destroy the dioxins. These methods require relatively high amounts of chemicals and wastewater management. However, they are supposed to be relatively cost effective. Other treatment options that are being tested at laboratory scale such as microbiological treatment and supercritical extraction are optimistic but have no realistic practical relevance at this state.

  14. 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

  15. 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.

  16. The change in the chemical form of copper in fly ash in a suitable temperature region for de novo synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Takaoka, M.; Shiono, A.; Nishimura, K.; Takeda, N.; Oshita, K.; Matsumoto, T.; Harada, H. [Kyoto Univ. (Japan). Dept. of Urban and Environ. Eng.; Yamamoto, T. [Tokyo Inst. of Tech., Yokohama (Japan). Chemical Resources Lab.; Uruga, T. [JASRI, Hyogo (Japan); Tanaka, T. [Kyoto Univ. (Japan). Dept. of Molecular Eng.

    2004-09-15

    Copper chloride as an important catalyst generates many polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) and related compounds in heat experiments involving model fly ash. We investigated the chemical forms of copper in actual fly ash before heating experiments and discuss the relationship that we discovered between the copper species Cu(OH){sub 2}, CuO, and Cu(OH){sub 2}.CuCO{sub 3}.H{sub 2}O and the formation of chlorinated aromatics in actual fly ash using X-ray absorption near-edge spectroscopy (XANES). Other results using model fly ash differ from ours. The thermal stabilities of these compounds are not high, so these compounds might not exist in fly ash in the temperature region suitable for de novo synthesis. Therefore, we conducted in situ XANES experiments using actual fly ash and two models of fly ash to understand the behavior of copper in fly ash in the temperature region suitable for de novo synthesis.

  17. 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.

  18. 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

  19. Steam hydration-reactivation of FBC ashes for enhanced in situ desulphurization

    Energy Technology Data Exchange (ETDEWEB)

    Fabio Montagnaro; Marianna Nobili; Antonio Telesca; Gian Lorenz Valenti; Edward J. Anthony; Piero Salatino [Universita degli Studi di Napoli Federico II, Napoli (Italy). Dipartimento di Chimica

    2009-06-15

    Bed and fly ashes originating from industrial-scale fluidized bed combustors (FBCs) were steam hydrated to produce sorbents suitable for further in situ desulphurization. Samples of the hydrated ash were characterized by X-ray diffraction analysis, scanning electron microscopy and porosimetry. Bed ashes were hydrated in a pressure bomb for 30 and 60 min at 200{sup o}C and 250{sup o}C. Fly ash was hydrated in an electrically heated tubular reactor for 10 and 60 min at 200{sup o}C and 300{sup o}C. The results were interpreted by considering the hydration process and the related development of accessible porosity suitable for resulphation. The performance of the reactivated bed ash as sulphur sorbent improved with a decrease of both the hydration temperature and time. For reactivated fly ash, more favourable porosimetric features were observed at longer treatment times and lower hydration temperatures. Finally, it was shown that an ashing treatment (at 850{sup o}C for 20 min) promoted a speeding up of the hydration process and an increase in the accessible porosity. 36 refs., 6 figs., 2 tabs.

  20. Investigation of Fly Ash and Activated Carbon Obtained from Pulverized Coal Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Edward K. Levy; Christopher Kiely; Zheng Yao

    2006-08-31

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addressed the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addressed the possible connection between SCR reactors, fly ash properties and Hg capture. The project has determined the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed have also been determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control have been analyzed in an effort to determine the effects of SCR on the ash.

  1. Adhesive carrier particles for rapidly hydrated sorbent for moderate-temperature dry flue gas desulfurization.

    Science.gov (United States)

    Li, Yuan; You, Changfu; Song, Chenxing

    2010-06-15

    A rapidly hydrated sorbent for moderate-temperature dry flue gas desulfurization was prepared by rapidly hydrating adhesive carrier particles and lime. The circulation ash from a circulating fluidized bed boiler and chain boiler ash, both of which have rough surfaces with large specific surface areas and specific pore volumes, can improve the adhesion, abrasion resistance, and desulfurization characteristics of rapidly hydrated sorbent when used as the adhesive carrier particles. The adhesion ability of sorbent made from circulation ash is 67.4% higher than that of the existing rapidly hydrated sorbent made from fly ash, the abrasion ratio is 76.2% lower, and desulfurization ability is 14.1% higher. For sorbent made from chain boiler ash, the adhesion ability is increased by 74.7%, the desulfurization ability is increased by 30.3%, and abrasion ratio is decreased by 52.4%. The abrasion ratios of the sorbent made from circulation ash having various average diameters were all about 9%, and their desulfurization abilities were similar (approximately 150 mg/g).

  2. 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'.

  3. Peptide-Carrier Conjugation

    DEFF Research Database (Denmark)

    Hansen, Paul Robert

    2015-01-01

    To produce antibodies against synthetic peptides it is necessary to couple them to a protein carrier. This chapter provides a nonspecialist overview of peptide-carrier conjugation. Furthermore, a protocol for coupling cysteine-containing peptides to bovine serum albumin is outlined....

  4. 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.

  5. 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.

  6. 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.

  7. Micro-analytical studies on sugar cane bagasse ash

    Indian Academy of Sciences (India)

    P Jagadesh; A Ramachandramurthy; R Murugesan; K Sarayu

    2015-08-01

    The worldwide production of sugar generates large volumes of bagasse wastes, which are burnt in uncontrolled manner for heating boiler, which are deposited in landfills, which create negative effects in the environment. The ash obtained by burning bagasse is generally used as Supplementary Cementing Material (SCM) in concrete production without proper knowledge of pozzolanic material characterization. This paper summarizes the results obtained from the various techniques to determine pozzolanic mineral profiles in sugarcane bagasse ash (SCBA). Techniques employed in the present study include X-Ray Diffraction (XRD), Energy-Dispersive X-ray Analysis (EDAX) spectrometer, Fourier Transform Infra-Red Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Thermal Analysis [Thermo-Gravimetric Analysis (TGA) and Derivative Thermo-Gravimetric (DTG)] in order to understand the type, form, nature, morphology, concentration, etc. of pozzolanic minerals.

  8. Kaliophilite from fly ash: synthesis, characterization and stability

    Indian Academy of Sciences (India)

    Yao Zhitong; Xia Meisheng; Ye Ying; Zhang Lu

    2011-12-01

    Kaliophilite was synthesized by fusion method using fly ash as starting material. In this method, at first, alkaline fusion of fly ash with KOH occurs, followed by hydrothermal treatment in KOH medium. Scanning electron microscopy (SEM) observations revealed that the synthesized kaliophilite (S-KAL) was a plate-like crystal. X-ray diffraction (XRD) results showed three characteristic diffraction peaks located at 2 = 19.56°, 20.78° and 28.71°, respectively. The thermal analysis indicated that the S-KAL had remarkable thermal stability when heated to 1000°C. Leaching test confirmed the high retention rate of potassium for S-KAL in boiling water for 10 h.

  9. Simulation of the ash exhaust in a fusion engineering reactor

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Kimitaka; Ueda, Noriaki; Itoh, Sanae; Sugihara, Masayoshi.

    1988-09-01

    Numerical analysis of the plasmas in the divertor and scrape-off layer (SOL) of a fusion engineering reactor (FER) is made by using the two-dimensional time-dependent simulation code. The equation for plasmas in the SOL and divertor regions is solved for the given particle and heat sources from the main plasma, GAMMA/sub out/ and Q/sub T/. For the given size of the pumping duct and the pumping speed, the necessary value of GAMMA/sub out/ for the ash exhaust is discussed. Sufficient ash exhaust is possible under the condition which is consistent with the scaling law of the particle and energy confinement of the main plasma.

  10. The Source of Volcanic Ash in Late Classic Maya Pottery at El Pilar, Belize

    Science.gov (United States)

    Catlin, B. L.; Ford, A.; Spera, F. J.

    2007-12-01

    The presence of volcanic ash used as temper in Late Classic Maya pottery (AD 600-900) at El Pilar has been long known although the volcano(s) contributing ash have not been identified. We use geochemical fingerprinting, comparing compositions of glass shards in potsherds with volcanic sources to identify the source(s). El Pilar is located in the Maya carbonate lowlands distant from volcanic sources. It is unlikely Maya transported ash from distant sites: ash volumes are too large, the terrain too rugged, and no draft animals were available. Ash layer mining is unlikely because mine sites have not been found despite intensive surveys. Nearest volcanic sources to El Pilar, Belize and Guatemala, are roughly 450 km to the south and east. The ash found in potsherds has a cuspate morphology. This suggests ash was collected during, or shortly after, an ash airfall event following eruption. Analyses of n=333 ash shards from 20 ceramic (pottery) sherds was conducted by electron microprobe for major elements, and LA-ICPMS for trace elements and Pb isotopes. These analyses can be compared to volcanic materials from candidate volcanoes in the region. The 1982 El Chichon eruption caused airfall deposition (pot firing on glass compositional changes, experiments were conducted in which high silica volcanic glass was fired with clay according to heating schedules used by Maya potters. Two important changes are that Na is rapidly lost preferentially to K and that the Si/Ca ratio decreases due to Ca diffusion from matrix into glass during firing. One expects that ratios of the refractory trace elements such as La/Yb and Zr/Hf are less susceptible to modification. Further experiments of trace element mobility during firing are underway.

  11. Contribution of Ash Content Related to Methane Adsorption Behaviors of Bituminous Coals

    Directory of Open Access Journals (Sweden)

    Yanyan Feng

    2014-01-01

    Full Text Available Methane adsorption isotherms on coals with varying ash contents were investigated. The textural properties were characterized by N2 adsorption/desorption isotherm at 77 K, and methane adsorption characteristics were measured at pressures up to 4.0 MPa at 298 K, 313 K, and 328 K, respectively. The Dubinin-Astakhov model and the Polanyi potential theory were employed to fit the experimental data. As a result, ash content correlated strongly to methane adsorption capacity. Over the ash range studied, 9.35% to 21.24%, the average increase in methane adsorption capacity was 0.021 mmol/g for each 1.0% rise in ash content. With the increasing ash content range of 21.24%~43.47%, a reduction in the maximum adsorption capacities of coals was observed. In addition, there was a positive correlation between the saturated adsorption capacity and the specific surface area and micropore volume of samples. Further, this study presented the heat of adsorption, the isosteric heat of adsorption, and the adsorbed phase specific heat capacity for methane adsorption on various coals. Employing the proposed thermodynamic approaches, the thermodynamic maps of the adsorption processes of coalbed methane were conducive to the understanding of the coal and gas simultaneous extraction.

  12. 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.

  13. Desulfurization characteristics of rapidly hydrated sorbents with various adhesive carrier particles for a semidry CFB-FGD system.

    Science.gov (United States)

    You, Changfu; Li, Yuan

    2013-03-19

    Semidry flue gas desulfurization (FGD) experiments were conducted using rapidly hydrated sorbents with four different adhesive carrier particles: circulation ash from a circulating fluidized bed boiler (CFBB circulation ash), fly ash from the first electrical field of the electrostatic precipitator of a circulating fluidized bed boiler (CFBB ESP ash), fly ash from a chain boiler (chain boiler ash), and river sand smaller than 1 mm. The influences of various adhesive carrier particles and operating conditions on the desulfurization characteristics of the sorbents were investigated, including sprayed water, reaction temperature, and the ratio of calcium to sulfur (Ca/S). The experimental results indicated that the rapidly hydrated sorbents had better desulfurization characteristics by using adhesive carrier particles which possessed better pore, adhesion, and fluidization characteristics. The desulfurization efficiency of the system increased as the reaction temperature decreased, it improved from 35% to 90% as the mass flow rate of the sprayed water increased from 0 to 10 kg/h, and it increased from 65.6% to 82.7% as Ca/S increased from 1.0 to 2.0. Based on these findings, a new semidry circulating fluidized bed (CFB)-FGD system using rapidly hydrated sorbent was developed. Using the rapidly hydrated sorbent, this system uses a cyclone separator instead of an ESP or a bag filter to recycle the sorbent particles, thereby decreasing the system flow resistance, saving investment and operating costs of the solids collection equipment.

  14. Composite cam carrier

    Energy Technology Data Exchange (ETDEWEB)

    Wicks, Christopher Donald; Madin, Mark Michael

    2017-03-14

    A cam carrier assembly includes a cylinder head having valves and a camshaft having lobes. A cam carrier has a first side coupled with the cylinder head engaging around the valves and a second side with bearing surfaces supporting the camshaft. A series of apertures extend between the first and second sides for the lobes to interface with the valves. The cam carrier is made of carbon fiber composite insulating the camshaft from the cylinder head and providing substantial weight reduction to an upper section of an associated engine.

  15. Asymmetric Carrier Random PWM

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Lungeanu, Florin; Rasmussen, Peter Omand;

    2010-01-01

    This paper presents a new fixed carrier frequency random PWM method, where a new type of carrier wave is proposed for modulation. Based on the measurements, it is shown that the spread effect of the discrete components from the motor current spectra is very effective independent of the modulation...... index. The flat motor current spectrum generates an acoustical noise close to the white noise, which may improve the acoustical performance of the drive. The new carrier wave is easy to implement digitally, without employing any external circuits. The modulation method can be used in open, as well...

  16. 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

  17. Product distribution of lignite pyrolysis with olivine-based solid heat carrier%橄榄石基固体热载体影响褐煤热解产物分布的分析

    Institute of Scientific and Technical Information of China (English)

    邓靖; 李文英; 李晓红; 喻长连; 冯杰; 郭小汾

    2013-01-01

    To improve the quality of tar,and reduce the heavy fraction (whose boiling points are greater than 360 ℃) in the tar,the lignite fast pyrolysis process using olivine and Co-impregnated olivine (Co/olivine) as the solid heat carrier was investigated in a fixed bed reactor over the temperature range 450 ~ 600 ℃.The effects of olivine and Co/olivine on the product yield,gas composition and tar fraction were examined.The results show that Co/olivine leads to a decrease in heavy oil fraction content,but an increase in tar yield.Co/olivine makes an increase in tar yield by 19.2% compared to the silica sand,while a decrease in heavy oil fraction content by 17.0% compared to the olivine at 550 ℃.The yield of light oil can reach up to 5.1%,however,the content of light oil,phenol oil and naphthalene oil increases by 19.6%,17% and 15.2%,respectively.Meanwhile,the content of H2 and CH4 in gaseous product is obviously decreased.%为了提高固体热载体煤热解工艺中焦油的品质,降低焦油中沸点大于360℃的重质组分含量,本实验采用固定床反应器,在450~600℃下进行褐煤固体热载体快速热解反应.分析对比了橄榄石基和石英砂固体热载体对褐煤热解产物收率、焦油馏分、气体组成的影响.结果发现,Co能改变煤内部挥发分氢元素的分布,橄榄石负载Co热载体能将焦油中重质组分转化为轻质焦油和热解气.热解温度为550℃时,与橄榄石相比,负载Co的橄榄石固体热载体使焦油收率提高了19.2%.与石英砂相比,负载Co的橄榄石固体热载体使焦油中重质组分含量降低了17.0%,轻质组分收率达5.1%,其中,轻油、酚油和萘油分别提高了19.6%、17%和15.2%,气体产物中H2、CH4含量下降.

  18. Measures to reduce carbon content of fly ash in CFB boilers

    Energy Technology Data Exchange (ETDEWEB)

    Shen, L.; Liu, D.C.; Zhang, S.H.; Chen, H.P. [HuaZhong Univ. of Science and Technology, National Laboratory of Coal Combustion (China); Huang, Y.P.; Liu, C.M. [Da Ye Power Plant, Hu-Bei (China); Winter, F. [Vienna Technical Univ., Vienna (Austria)

    2002-07-01

    There is a significant need to develop clean coal combustion technology in China, given that the major energy source is coal, accounting for 75 per cent of primary energy. Circulating fluidized bed (CFB) combustion offers high combustion intensity with low pollutant emissions. It also has good combustion stability and excellent fuel flexibility. However, the high carbon content of the fly ash and the low boiler heat efficiency are two problems that must be addressed, particularly for middle and small sized CFB boilers. This study examined several reasons for high carbon content of fly ash in CFB boilers, including the distribution of particle size, the heating value of the coal and the fractional return of cold material to the combustion chamber. Operating conditions of the fly ash circulating combustion system were also examined. Proven effective measures to reduce carbon content were then suggested. 4 refs., 2 tabs., 2 figs.

  19. Influence of fly ash added to a ceramic body on its thermophysical properties

    Directory of Open Access Journals (Sweden)

    Kováč Jozef

    2016-01-01

    Full Text Available We study thermal expansion, mass changes, heat capacity, and thermal diffusivity and conductivity for a ceramic body with 20 mass% and without fly ash content, using the TDA, TG, DTA, DSC, and flash method. The measurements were performed (a for green samples either isothermally or by a linear heating up to a temperature 600°C, 1050°C, or 1100°C, depending on the measurement method; (b at the room temperature for samples preheated at 100°C, 200°C, ..., 1100°C. In case (a addition of fly ash changes the final contraction only above ~900°C, while the thermal properties remain almost unchanged. In case (b the final contraction of samples at 1100°C is the same. The thermal diffusivity is nearly identical up to 700°C, and fly ash causes the diffusivity to stay almost constant up to 1000°C.

  20. 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.

  1. 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.

  2. 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.

  3. Gasification reactivity and ash behaviour of biomass fuels

    Energy Technology Data Exchange (ETDEWEB)

    Moilanen, A.; Kurkela, E. [VTT Energy, Espoo (Finland)

    1998-12-31

    Measuring data required for describing the reactivity and ash sintering behaviour of biomass-based solid fuels for atmospheric and pressurised gasification are discussed. The measurements were carried out in a pressurisable thermobalance and bench-scale fluidised bed reactors. The main variables were temperature and partial pressures of H{sub 2}O and H{sub 2}, and CO{sub 2} and CO. The reaction rates were determined in binary gas mixtures H{sub 2}O-H{sub 2}, and CO{sub 2}-CO as well as in product gas mixtures H{sub 2}O-H{sub 2}-CO{sub 2}-CO. The total pressure range was 1-30 bar and the temperature range 650-950 deg C. For wood, kinetic parameters were determined using the Langmuir-Hinshelwood kinetics, which takes into account the effect of the product gases on the reaction rate. The results indicated that the H{sub 2}O-H{sub 2} system was well in conformity with this kinetics, while the reaction rates measured for the CO{sub 2}-CO system required the description of the catalytic effects of the ash-forming material. In the gasification of wood as well as of other biomasses, the behaviour of catalytically active ash components is more complex during char gasification. Experimental set-ups used for gasification reactivity measurements were compared in Aabo Akademi University and in VTT. The set-ups were pressurised thermogravimetric reactor (PTG), pressurised grid heater (PGH), pressurised bench-scale fluidised bed reactor (PFB), and pressurised entrained flow reactor (PEF). In addition, the effect of stabilising heat treatment was tested. The samples used in the study were wood, black liquor, peat, and coal. The gasification reactivity measurements were carried out in the temperature range of 700-950 deg C, and in the pressure range of 1-10 bar. The gasification agent was either CO{sub 2} in N{sub 2} or CO-CO{sub 2} mixture in N{sub 2}. In the pyrolysis carried out in different devices, mainly the same pressure and temperature were used as in the char gasification

  4. Effect of Carbon Ash Content on the Thermal and Combustion Properties of Waste Wood Particle / Recycled Polypropylene Composites

    Directory of Open Access Journals (Sweden)

    Chen Kuo-Wei

    2016-01-01

    Full Text Available This study effect of carbon ash content on the thermal stability and combustion behavior of waste wood particle / recycled polypropylene composites was investigated using TGA, DTG, LOI and cone calorimeter. The TGA shows that, as carbon ash content increases, the thermal stability of composites increases, while the residual weight significantly increases, with the residual weight rate of waste wood particle / recycled polypropylene composites increases from 13.97% to 41.02% at 800 ℃ According to cone calorimeter results, in the 50 kW/M2 thermal flow, when carbon ash adding to 70%, peak heat release rate and total heat release quantity, decreases by 68% and 52%, respectively. The LOI of waste wood particle / recycled polypropylene composites improves by about 34%, Conforming UL-94 flammability standard, V-0 rating. The residual weight rate increases by 202.8%, which the significant role of carbon ash in flame retardant.

  5. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-07-01

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

  7. Volcanic ash infrared signature: porous non-spherical ash particle shapes compared to homogeneous spherical ash particles

    OpenAIRE

    A. Kylling; Kahnert, M.; Lindqvist, H.; T. Nousiainen

    2014-01-01

    The reverse absorption technique is often used to detect volcanic ash clouds from thermal infrared satellite measurements. From these measurements effective particle radius and mass loading may be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculated thermal infrared optical properties of highly irregular and porous ash particles and compared these with mass- and volume-equivalent sp...

  8. Ash Content and Calorific Energy of Corn Stover Components in Eastern Canada

    Directory of Open Access Journals (Sweden)

    Pierre-Luc Lizotte

    2015-05-01

    Full Text Available Corn stover is an abundant agricultural residue that could be used on the farm for heating and crop drying. Ash content and calorific energy of corn grain and six stover components were measured from standing plants during the grain maturing period, between mid-September and mid-November. Ash of stover in standing corn averaged 4.8% in a cool crop heat unit zone (2300–2500 crop heat units (CHU and 7.3% in a warmer zone (2900–3100 CHU. The corn cob had the lowest ash content (average of 2.2% while leaves had the highest content (from 7.7% to 12.6%. In the fall, ash content of mowed and raked stover varied between 5.5% and 11.7%. In the following spring, ash content of stover mowed, raked and baled in May averaged 3.6%. The cob and stalk located below the first ear contained the highest calorific energy with 17.72 MJ·kg−1. Leaves and grain had the lowest energy with an average of 16.99 MJ·kg−1. The stover heat of combustion was estimated at 17.47 MJ·kg−1 in the cool zone and 17.26 MJ·kg−1 in the warm zone. Based on presented results, a partial “cob and husk” harvest system would collect less energy per unit area than total stover harvest (44 vs. 156 GJ·ha−1 and less biomass (2.51 vs. 9.13 t·dry matter (DM·ha−1 but the fuel quality would be considerably higher with a low ash-to-energy ratio (1.45 vs. 4.27 g·MJ−1.

  9. Volcanic ash infrared signature: porous non-spherical ash particle shapes compared to homogeneous spherical ash particles

    Science.gov (United States)

    Kylling, A.; Kahnert, M.; Lindqvist, H.; Nousiainen, T.

    2014-04-01

    The reverse absorption technique is often used to detect volcanic ash clouds from thermal infrared satellite measurements. From these measurements effective particle radius and mass loading may be estimated using radiative transfer modelling. The radiative transfer modelling usually assumes that the ash particles are spherical. We calculated thermal infrared optical properties of highly irregular and porous ash particles and compared these with mass- and volume-equivalent spherical models. Furthermore, brightness temperatures pertinent to satellite observing geometry were calculated for the different ash particle shapes. Non-spherical shapes and volume-equivalent spheres were 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 was found to underestimate mass loading compared to morphologically complex inhomogeneous ash particles. The underestimate increases with the mass loading. For an ash cloud recorded during the Eyjafjallajökull 2010 eruption, the mass-equivalent spheres underestimate the total mass of the ash cloud by approximately 30% compared to the morphologically complex inhomogeneous particles.

  10. Comparisons of Fly Ash and Deposition Between Air and Oxy-Fuel Combustion in Bench-Scale Fluidized Bed with Limestone Addition

    Institute of Scientific and Technical Information of China (English)

    Zhimin Zheng; Hui Wang∗; Yongjun Guo; Li Yang; Shuai Guo; Shaohua Wu

    2015-01-01

    In Oxy⁃fuel circulating fluidized bed, the residual CaO particles may react with high concentration of CO2 in flue gas to form bonded deposit on heat transfer surfaces in backpass when limestone is used as a sorbent to capture SO2 .In this paper, experiments were designed on ash deposition in a bench⁃scale fluidized bed under oxy⁃fuel and air atmosphere. A novel ash deposit sampling probe was used to simulate the tubes of tail surfaces. The chemical composition of fly ash and ash deposit from both air⁃firing and oxy⁃fuel firing cases were analyzed by Inductively Coupled Plasma⁃Atomic Emission Spectrometry ( ICP⁃AES ) and Scanning Electron Microscopy ( SEM) , respectively. The degrees of carbonation reaction of ash deposits were measured by Thermo Gravimetric Analysis. The results showed that there are distinct differences in fly ash deposition rate between oxy⁃fuel and air firing cases, and oxy⁃fuel combustion with limestone addition can affect chemical composition of fly ash and ash deposit, especially for elements of Ca, Na, K, and S. However, the carbonation reaction degree of ash deposits is found weak, which is due to the relatively low CaO content in ash deposit or not long enough of the sampling time.

  11. Photoinduced Transformation between Charge Carrier and Spin Carrier in Polymers

    Institute of Scientific and Technical Information of China (English)

    MEI Yuan; ZHAO Chang; SUN Xin

    2006-01-01

    By dynamical simulations, we show a transforming process between neutral soliton (spin carrier) and charged soliton (charge carrier) in polymers via photo-excitation, taking a polaron as the transitional bridge. It is photoinduced transformation between spin carrier and charge carrier. In this way, we demonstrate an access for polymers to be applied to spintronics.

  12. ASHES AS AN AGENT FOR CEMENT-LIME BASED SOLIDIFICATION/STABILIZATION OF THE HAZARDOUS WASTE

    Directory of Open Access Journals (Sweden)

    Barbora Lyčkova

    2008-12-01

    Full Text Available One of the common treatment methods for the hazardous waste is the cement and cement-lime based solidification/stabilization (S/S. This article deals with the possibility of currently used recipe modification using fluidized bed heating plant ashes as an agent.

  13. Extending the capabilities of CFD codes to assess ash related problems

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen; Rosendahl, Lasse Aistrup; Baxter, B. B.

    2004-01-01

    entirely through a graphical userinterface integrated in the standard FLUENT? interface. The modelconsiders fine and coarse mode ash deposition and stickingmechanisms for the complete deposit growth, as well as an influenceon the local boundary conditions for heat transfer due to thermalresistance changes...

  14. Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

    Science.gov (United States)

    This paper/presentation is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practicall...

  15. Soot, organics and ultrafine ash from air- and oxy-fired coal combustion

    Science.gov (United States)

    This paper is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practically relevant s...

  16. Unburned Carbon Loss in Fly Ash of CFB Boilers Burning Hard Coal

    Institute of Scientific and Technical Information of China (English)

    L(U) Junfu(吕俊复); WANG Qimin(王启民); LI Yong(黎永); YUE Guangxi(岳光溪); Yam Y.Lee; Baldur Eliasson; SHEN Jiezhong(沈解忠); YU Long(于龙)

    2003-01-01

    The unburned carbon loss in fly ash of circulating fluidized bed (CFB) boilers, most of which are burning active fuels such as lignite or peat, is normally very low. However, most CFB boilers in China usually burn hard coals such as anthracite and bituminous coal and coal wastes, so the carbon content in the fly ash from these boilers is higher than expected. This paper investigates the source of unburned carbon in the fly ash of CFB boilers burning hard coal through a series of field tests and laboratory investigations. The char behavior during combustion, including fragmentation and deactivation, which is related to the parent coal, has an important impact on the carbon burnout in CFB boilers. The research shows that char deactivation occurs during char burnout in fluidized bed combustion, especially for large particles of low rank coal. The uneven mixing of solids and air in the core region of the furnace also causes poor burnout of carbon in CFB fly ash. An index describing the volatile content (as dry ash free basis) over the heating value is proposed to present the coal rank. The coal combustion efficiency is shown to be strongly connected with this coal index. Several changes in the CFB boiler design are suggested to reduce the unburned carbon loss in the fly ash.

  17. 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.

  18. 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.

  19. As and Se interactions with fly ashes

    Directory of Open Access Journals (Sweden)

    M. Díaz-Somoano

    2012-03-01

    Full Text Available Arsenic and selenium are toxic elements present incoal in trace concentrations that may be emitted tothe environment during coal conversion processes.However, it is possible to retain volatile arsenic andselenium compounds in the fly ashes originated bythe process, the proportions retained depending onthe characteristics of the ashes and processconditions. This work is focused on the capture ofthese elements in fly ashes in simulated coalcombustion and gasification atmospheres inlaboratory scale reactors.

  20. Characterization and valorization of biomass ashes.

    Science.gov (United States)

    Trivedi, Nikhilesh S; Mandavgane, Sachin A; Mehetre, Sayaji; Kulkarni, Bhaskar D

    2016-10-01

    In India, farming is the primary source of income for many families. Following each harvest, a huge amount of biomass is generated. These are generally discarded as "agrowaste," but recent reports have indicated several beneficial uses for these biomasses and their ashes. However, before the utilization of biomass ashes (BMAs), their chemical and physical properties need to be investigated (characterized) so as to utilize their potential benefit to the fullest. In this paper, eight different biomass ashes (soybean plant ash, mustard plant ash, maize ash, groundnut plant ash, cotton plant ash, wheat plant ash, pigeon peas ash, and groundnut shell ash) were characterized, and their chemical properties are discussed. Surface chemical composition analysis, proximate analysis, and ultimate analysis were performed on all BMA samples, and properties such as porosity, particle density, bulk density, point of zero charge, BET surface area, water-absorption capacity, and bulk parameters such as surface pH and surface charges were determined. BMAs were characterized by SEM and FTIR. The surface areas of biomass ashes vary from 1.9 to 46 m(2)/g, and point of zero charge for all BMAs exceed 9.8, which confirmed the alkaline nature of these samples. Based on the chemical composition, BMAs are categorized into four types (S, C, K, and CK), and their utilization is proposed based on the type. BMAs find applications in agriculture and construction industries; glass, rubber, and zeolite manufacturing; and in adsorption (as a source of silica/zeolites). The paper also discusses the research challenges and opportunities in utilization of BMAs.

  1. Thermal ageing on the microstructure and mechanical properties of Al–Cu–Mg alloy/bagasse ash particulate composites

    Directory of Open Access Journals (Sweden)

    V.S. Aigbodion

    2014-07-01

    Full Text Available Thermal ageing on the microstructure and mechanical properties of Al–Cu–Mg alloy/bagasse ash(BAp particulate composites was investigated. The composites were produced by a double stir-casting method by varying bagasse ash from 2 to 10 wt.%. After casting the samples were solution heat-treated at a temperature of 500 °C in an electrically heated furnace, soaked for 3 h at this temperature and then rapidly quenched in water and thermal aged at temperatures of 100, 200 and 300 °C. The ageing characteristics of these grades of composites were evaluated using scanning electron microscopy (SEM, hardness and tensile test samples obtained from solution heat-treated composites samples subjected to the temperature conditions mentioned above. The results show that the uniform distribution of the bagasse ash particles in the microstructure of both the as-cast and age-hardened Al–Cu–Mg/BAp composites is the major factor responsible for the improvement in mechanical properties. The presence of the bagasse ash particles in the matrix alloy results in a much smaller grain size in the cast composites compared to the matrix alloy. The addition of bagasse ash particles to Al–Cu–Mg (A2009 does not alter the thermal ageing sequence, but it alters certain aspects of the precipitation reaction. Although thermal ageing is accelerated in the composites the presence of bagasse ash particles in A2009 reduces the peak temperatures.

  2. Combustion of stoker ash in a CFBC

    Energy Technology Data Exchange (ETDEWEB)

    Jia, L.; Anthony, E.J. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy Technology Centre

    2002-07-01

    The ash generated from petroleum coke fired stokers at Georgia Pacific in Wisconsin has an elevated carbon content and a higher fuel value. This paper presents results of a study in which the stoker ash was test fired at the CANMET Energy Technology Centre in a bench scale circulating fluidized bed combustor (CFBC). The objective was to determine if firing the stoker ash in its 'as received' state (with a 40 per cent moisture content) is a viable fuel option for Georgia Pacific's FBC boiler to save fuel costs, or if it should be co-fired with petroleum coke. Mixtures of the stoker ash and petroleum coke were also test fired. Results indicate that the stoker ash alone cannot sustain combustion. However, good ignition and even bed temperature is possible with premixed coke and 10 per cent less moisture content. Emissions of sulphur dioxides, nitrogen oxides carbon monoxide were the same as for firing petroleum coke alone. In addition, the co-firing of stoker ash and petroleum coke did not negatively affect the tendency to foul, compared to firing coke alone. The amount of ash generated from the FBC boiler was high due to the high ash content. An economic evaluation showed that firing a 20/80 coke/stoker ash mixture can save approximately 22 per cent of the limestone usage compared to coke firing alone, if the Ca/S molar ratio remain the same. 8 refs., 2 tabs., 1 fig.

  3. Volcanic ash at Santiaguito dome complex, Guatemala

    Science.gov (United States)

    Hornby, Adrian; Kendrick, Jackie; Lavallée, Yan; Cimarelli, Corrado; von Aulock, Felix; Rhodes, Emma; Kennedy, Ben; Wadsworth, Fabian

    2015-04-01

    Dome-building volcanoes often suffer episodic explosions. Examination of eruptive activity at Santiaguito dome complex (Guatemala) reveals that gas-and-ash explosions are concordant with rapid inflation/ deflation cycles of the active dome. During these explosions strain is accommodated along marginal faults, where tensional fracture mechanisms and friction dominate, complicating the model of ash generation by bubble rupture in magma. Here, we describe textural features, morphology and petrology of ash collected before, during and after a dome collapse event at Santiaguito dome complex on the 28th November 2012. We use QEM-scan (on more than 35000 grains), laser diffraction granulometry and optical and scanning microscopy to characterise the samples. The ash samples show a bimodal size distribution and a range of textures, crystal content and morphologies. The ash particles are angular to sub-angular and are relatively dense, so do not appear to comprise of pore walls. Instead the ash is generally blocky (>70%), similar to the products of shear magma failure. The ash samples show minor variation before, during and after dome collapse, specifically having a smaller grain size and a higher fraction of phenocrysts fragments before collapse. Textural analysis shows vestiges of chemically heterogeneous glass (melt) filaments originating from the crystals and crosscut by fragmentation during volcanic ash formation. High-velocity friction can induce melting of dome lavas, producing similar disequilibrium melting textures. This work shows the importance of deformation mechanisms in ash generation at lava domes and during Vulcanian activity.

  4. Solidification on fly ash, Yugoslav experiences

    Energy Technology Data Exchange (ETDEWEB)

    Knezevic, D. [Mining Institute, Belgrade (Yugoslavia); Popov, S.; Salatic, D. [Faculty of Mining and Geology, Belgrade (Yugoslavia)

    1997-12-31

    A study was performed on ashes produced in the combustion process of coal from the Kosovo coal basin, in order to determine the potential and conditions of ash self-solidification. Investigations showed that the ash properties allows for the transformation into a solid mass through a controlled mixing with water. The optimal concentration of ash is 50 percent and the hydro-mixture is behaving as a Bingham plastic fluid. Solidification is obtained in a relatively short period (within 3 to 5 days) without additives. The resulting solidified mass is very consistent and stable

  5. 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.)

  6. Direct Quantitative Analysis of Arsenic in Coal Fly Ash

    Directory of Open Access Journals (Sweden)

    Sri Hartuti

    2012-01-01

    Full Text Available A rapid, simple method based on graphite furnace atomic absorption spectrometry is described for the direct determination of arsenic in coal fly ash. Solid samples were directly introduced into the atomizer without preliminary treatment. The direct analysis method was not always free of spectral matrix interference, but the stabilization of arsenic by adding palladium nitrate (chemical modifier and the optimization of the parameters in the furnace program (temperature, rate of temperature increase, hold time, and argon gas flow gave good results for the total arsenic determination. The optimal furnace program was determined by analyzing different concentrations of a reference material (NIST1633b, which showed the best linearity for calibration. The optimized parameters for the furnace programs for the ashing and atomization steps were as follows: temperatures of 500–1200 and 2150°C, heating rates of 100 and 500°C s−1, hold times of 90 and 7 s, and medium then maximum and medium argon gas flows, respectively. The calibration plots were linear with a correlation coefficient of 0.9699. This method was validated using arsenic-containing raw coal samples in accordance with the requirements of the mass balance calculation; the distribution rate of As in the fly ashes ranged from 101 to 119%.

  7. Automated Manufacture of Fertilizing Agglomerates from Burnt Wood Ash

    Energy Technology Data Exchange (ETDEWEB)

    Svantesson, Thomas

    2002-12-01

    In Sweden, extensive research is conducted to find alternative sources of energy that should partly replace the electric power production from nuclear power. With the ambition to create a sustainable system for producing energy, the use of renewable energy is expected to grow further and biofuels are expected to account for a significant part of this increase. However, when biofuels are burned or gasified, ash appears as a by-product. In order to overcome the problems related to deposition in land fills, the idea is to transform the ashes into a product - agglomerates - that easily could be recycled back to the forest grounds; as a fertilizer, or as a tool to reduce the acidification in the forest soil at the spreading area. This work considers the control of a transformation process, which transforms wood ash produced at a district heating plant into fertilizing agglomerates. A robust machine, built to comply with the industrial requirements for continuous operation, has been developed and is controlled by an industrial control system in order to enable an automated manufacture.

  8. Combined glassification of EAF dust and incinerator fly ash.

    Science.gov (United States)

    Cheng, T W

    2003-01-01

    Stainless steelmaking dust contains large amount of heavy metals, such as Cr and Ni. If these hazardous materials are not treated properly, they will cause detrimental secondary contamination. Preliminary study on recycling stainless steelmaking dust employed the thermal molten technology. Glass-ceramics were formed by combination stainless steel dust and incinerator fly ash with the ratio of 1:9. The major phases were Augite, Akermanite, and Donathite. It was found that the glass-ceramics shows the best characteristic at 900 degrees C after 5 h of heat treatment. This product can be used as building materials or refractory materials.

  9. The characteristics of coal blends -- Milling behavior and ash fusion temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Livingston, W.R.; Horne, P.A.; McGhee, B.F.; Gibson, J.R.; Chakraborty, R.K.

    1998-07-01

    In this paper, the results of a program of experimental work on the milling characteristics and the ash fusion behavior of coal blends are presented. The milling behavior has been studied in two ways: By measurement of the Hardgrove Index and the Abrasion Index values for blends of a series of coal pairs, and by the performance of a program of testwork using the Mini-mill Test Facility at Mitsui Babcock Energy Limited in Renfrew, Scotland. Four coal blend pairs, selected to provide a range of Hardgrove Index values between 45 and 69 were studied. It was found that the Hardgrove Index and the Abrasion Index are simple additive properties. This means that there is a straight line relationship between the measured value for the fuel property and the blend composition and that the value for a particular blend can be calculated by simple proportion from the values for the constituent coals. The Mini-mill results indicated that there are very good linear correlations between the new surface area produced during milling, the energy consumption per unit new surface area and the slope of the Rosin-Rammler plot of the mill product size distribution with the blend composition. The ash fusion behavior of the coal blends was studied in two ways: By measurement of the standard Ash Fusion Temperatures, and by using a novel technique which involves measurement of the electrical resistivity and linear shrinkage of the ash as it is heated in the range 900-1,400 C. Six coal ash blend pairs were studied, covering the full range of ash fusion behavior encountered in European coal-fired plant. It was found that the ash fusion temperatures are not additive and that, in all cases, the fusion temperatures of the blends were lower than the additive line. The deviation from additive behavior depends on the difference in the ash fusion temperatures of the constituent coals.

  10. Self hardening property of Botswana fly ash | Sahu | Botswana ...

    African Journals Online (AJOL)

    Self hardening property of Botswana fly ash. ... In the present investigation, an effort has been made to study the self hardening property of Botswana fly ash by ... This will encourage the use of fly ash economically as a construction material.

  11. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett [Park City, UT

    2012-05-15

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

  12. Behavior and Mechanism of Pozzolanic Reaction Heat of Fly Ash and Ground Granulated Blastfurnace Slag at Early Age%粉煤灰与矿渣的早期火山灰反应放热行为及其机理

    Institute of Scientific and Technical Information of China (English)

    王冲; 杨长辉; 钱觉时; 钟明全; 赵爽

    2012-01-01

    针对大体积混凝土绝热温升计算中粉煤灰与矿渣的火山灰反应放热问题,利用微量热仪法测试了不同掺量粉煤灰和矿渣对水泥水化热及放热速率的影响规律,分析了粉煤灰和矿渣水化3d以前的火山灰反应放热行为,采用X射线衍射与差示扫描量热–热重法研究了粉煤灰与矿渣对水泥早期水化及其火山灰放热行为的影响机理。结果表明:粉煤灰与矿渣水化3d时火山灰反应热分别约为3~5J/g和15~16J/g。粉煤灰对水泥水化的阻碍作用在水化24h前最为明显,其火山灰效应主要发生于水化24h之后;矿渣对水泥水化有促进作用,自加水开始即表现出一定的火山灰效应。粉煤灰与矿渣掺入后有助于水泥水化产物中钙矾石的稳定,钙矾石抑制了水泥水化,Ca(OH)2生成量减少,因而粉煤灰与矿渣的火山灰反应也受到影响。%In order to evaluate the pozzolanic reaction heat of fly ash (FA) and ground granulated blastfumace slag (GGBS) in temperature simulation of mass concrete, the influence of replacement of FA and GGBS on the hydration process and heat rate of cement was investigated via microcalorimetry, and the behaviors of pozzolanic reaction heat of FA and GGBS before 3 d were analyzed. Reaction heat of FA and GGBS at early age was discussed by X-ray diffraction and differential scanning calorimetry-thermogravimetry (DSC-TG), respectively. The mechanism of pozzolanic. The results show that the pozzolanic reaction heat of FA and GGBS is 3-5 J/g and 15-16 J/g. The FA has a negative effect on the cement hydration before 24 h, but its pozzolanic effect plays a positive effect on the cement hydration after 24 h. The pozzolanic effect of the GGBS accelerates the cement hydration at early age. Ettringite is more steady in the cement hydration production when FA or GGBS is added, which delays the hydration of cement and produce of Ca(OH)2 Therefore, the pozzolanic

  13. 10 Risk to Ash from Emerald Ash Borer: Can Biological Control Prevent the Loss of Ash Stands

    Science.gov (United States)

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

  14. Emerald ash borer biocontrol in ash saplings: The potential for early stage recovery of North American ash trees

    Science.gov (United States)

    Jian J. Duan; Leah S. Bauer; Roy G. Van Driesche

    2017-01-01

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

  15. Carrier transport uphill. I. General

    DEFF Research Database (Denmark)

    Rosenberg, T; Wilbrandt, W

    1963-01-01

    A quantitative treatment of a carrier pump operating with two carrier forms C and Z is presented. Asymmetric metabolic reactions are assumed to transform Z into C on one and C into Z on the other side of the membrane, establishing a carrier cycle. The kinetical consequences of this mechanism...... concords with equilibrating carrier systems in all characteristic kinetical features is taken to indicate that the carrier mechanism contributes more to the characteristic transport features than the connection with metabolism....

  16. State of volcanic ash dispersion prediction

    Science.gov (United States)

    Eliasson, Jonas; Palsson, Thorgeir; Weber, Konradin

    2017-04-01

    The Eyjafjallajokull 2010 and Grimsvotn 2011 eruptions created great problems for commercial aviation in Western Europe and in the North Atlantic region. Comparison of satellite images of the visible and predicted ash clouds showed the VAAC prediction to be much larger than the actual ash clouds. No official explanation of this discrepancy exists apart from the definition of the ash cloud boundary. Papers on simulation of the Eyjafjallajökull ash cloud in peer reviewed journals, typically attempted to simulate the VAAC predictions rather than focusing on the satellite pictures. Sporadic measurements made in-situ showed much lower ash concentrations over Europe than the predicted values. Two of the weak points in ash cloud prediction have been studied in airborne measurements of volcanic ash by the Universities in Kyoto Japan, Iceland and Düsseldorf Germany of eruptions in Sakurajima, Japan. It turns out that gravitational deformation of the plume and a streak fallout process make estimated ash content of clouds larger than the actual, both features are not included in the simulation model. Tropospheric plumes tend to ride in stable inversions this causes gravitational flattening (pancaking) of the volcanic plume, while diffusion in the mixing layer is insignificant. New rules from ICAO, effective from November 2014, reiterate that jetliners should avoid visible ash, this makes information on visible ash important. A procedure developed by JMÁs Tokyo VAAC uses satellite images of visible ash to correct the prediction. This and the fact that meteorological data necessary to model gravitational dispersion and streak fallout do not exist in the international database available to the VAAĆs. This shows that close monitoring by airborne measurements and satellite and other photographic surveillance is necessary.

  17. Characteristics of spanish fly ashes

    Directory of Open Access Journals (Sweden)

    de Luxán, M. P.

    1988-03-01

    Full Text Available The purpose of this study is the characterization of fly ashes produced by Spanish thermoelectric power plants, according to sampling taken in 1981 and 1982. The study takes in the following characteristics: physical characteristics (size distribution of particles, ...; chemical ones (chemical analysis...; and mineralogical ones (application of instrumental techniques of X-ray diffraction and infrared absorption spectroscopy. From a general point of view, it can be said that the samples of Spanish fly ashes are similar to those produced in other countries. The results obtained are a contribution to the knowledge of Spanish fly ashes and form part of the antecedents of investigations carried out in subsequent years.

    Este trabajo tiene por objeto la caracterización de las cenizas volantes producidas en las Centrales Termoeléctricas españolas, según un muestreo realizado entre 1981 y 1982. El estudio comprende las siguientes características: físicas (distribución del tamaño de partículas,...; químicas (análisis químico, …; y mineralógicas (aplicación de las técnicas instrumentales de difracción de rayos X y espectroscopía de absorción infrarroja. Desde un punto de vista general, se puede afirmar que las muestras de ceniza volante estudiadas son semejantes a las producidas en otros países. Los resultados obtenidos son una aportación al conocimiento de las cenizas volantes españolas y forman parte de los antecedentes de las investigaciones llevadas a cabo en años posteriores.

  18. Characterization of fly ash from bio and municipal waste

    DEFF Research Database (Denmark)

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

    2008-01-01

    Four different fly ashes are characterized in the present paper. The ashes differ in the original fuel type and were sampled at distinct plants. The investigation includes two different ashes from municipal solid waste incineration (with and without sorbents addition), a straw ash and an ash from...... potentiality to be valorized. The main conclusion of this paper regards fly ash’s profound dissimilarity, where each ash should be studied separately....

  19. 具有高比表面积的稻壳灰的制备及其化学活性的研究%Study on Preparation of Rice Husk Ash with High Specific Surface Area and Its Chemical Reactivity

    Institute of Scientific and Technical Information of China (English)

    冯庆革; 林清宇; 童张法; S.Sugita

    2004-01-01

    Preparation of rice husk ash with high specific surface area and chemical reactivity of the product are reported in this paper. The amorphous rice husk ash with high specific surface area of 311 m2·g-1 was produced by heating acid treated rice husk at 700℃ for 4 h. The isotherms of rice husk ash are similar in shape to type Ⅱof Brunaner's classification with mesopores being predominant. The rice husk ash has a high chemical reactivity,especially that pretreated with acid. This chemical reactivity depends on ashing temperature and pretreatment conditions. There is an exponential relation between the specific surface area of rice husk ash and the change in the conductivity of saturated Ca(OH)2 solution with rice husk ash, from which the specific surface area can be known according to the conductivity change.

  20. Effect of orientation on heat transfer in pulsating heat pipe

    Directory of Open Access Journals (Sweden)

    Naumova A. M.

    2010-10-01

    Full Text Available The paper presents the results of experimental research of orientation effect on heat transfer characteristics of a pulsating heat pipe (PHP. It is shown that transport of either mass or heat depends on PHP orientation against it`s axis. As a consequence of comparing experimental data with other authors’ results it was concluded that PHP thermal resistance depends not only on orientation but on some other determinal factors such as device construction and thermophysical properties of heat carrier.

  1. Research of heat exchange rate of the pulsating heat pipe

    Directory of Open Access Journals (Sweden)

    Kravets V. Yu.

    2010-02-01

    Full Text Available Given article presents experimental research of heat transfer characteristics of the pulsating heat pipe (PHP which consists of seven coils with 1 mm inner diameter. Water was used as the heat carrier. PHP construction, measuring circuit and research technique are presented. It is shown that under PHP functioning there are two characteristic modes of operation, which can be distinguished by values of thermal resistance. PHP heat exchange features are disclosed.

  2. Waste heat generation: A comprehensive review.

    Science.gov (United States)

    Yeşiller, Nazli; Hanson, James L; Yee, Emma H

    2015-08-01

    A comprehensive review of heat generation in various types of wastes and of the thermal regime of waste containment facilities is provided in this paper. Municipal solid waste (MSW), MSW incineration ash, and mining wastes were included in the analysis. Spatial and temporal variations of waste temperatures, thermal gradients, thermal properties of wastes, average temperature differentials, and heat generation values are provided. Heat generation was influenced by climatic conditions, mean annual earth temperatures, waste temperatures at the time of placement, cover conditions, and inherent heat generation potential of the specific wastes. Time to onset of heat generation varied between months and years, whereas timelines for overall duration of heat generation varied between years and decades. For MSW, measured waste temperatures were as high as 60-90°C and as low as -6°C. MSW incinerator ash temperatures varied between 5 and 87°C. Mining waste temperatures were in the range of -25 to 65°C. In the wastes analyzed, upward heat flow toward the surface was more prominent than downward heat flow toward the subsurface. Thermal gradients generally were higher for MSW and incinerator ash and lower for mining waste. Based on thermal properties, MSW had insulative qualities (low thermal conductivity), while mining wastes typically were relatively conductive (high thermal conductivity) with ash having intermediate qualities. Heat generation values ranged from -8.6 to 83.1MJ/m(3) and from 0.6 to 72.6MJ/m(3) for MSW and mining waste, respectively and was 72.6MJ/m(3) for ash waste. Conductive thermal losses were determined to range from 13 to 1111MJ/m(3)yr. The data and analysis provided in this review paper can be used in the investigation of heat generation and thermal regime of a wide range of wastes and waste containment facilities located in different climatic regions.

  3. Biomass fly ash in concrete: SEM, EDX and ESEM analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shuangzhen Wang; Larry Baxter; Fernando Fonseca [Brigham Young University, Provo, UT (USA). Department of Chemical Engineering

    2008-03-15

    This document summarizes microscopy study of concrete prepared from cement and fly ash (25% fly ash and 75% cement by weight), which covers coal fly ash and biomass fly ash. All the fly ash concrete has the statistical equal strength from one day to one year after mix. Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) and environmental scanning electron microscopy (ESEM) analysis show that both coal and biomass fly ash particles undergo significant changes of morphology and chemical compositions in concrete due to pozzolanic reaction, although biomass fly ash differs substantially from coal fly ash in its fuel resources. 8 refs., 17 figs., 1 tab.

  4. Electrodialytic removal of heavy metals from fly ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul

    2002-01-01

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

  5. Geothermal heat in a heat pump use

    Science.gov (United States)

    Pavlova, A.; Hansen, J.; Obermeyer, H.; Pavlova, I.

    2016-09-01

    The considered innovative technology proposes to use alternative energy sources for the process efficiency in low-height construction. The world economy depends on price rises for energy sources and the danger of environmental pollution increases. Geothermal energy is the basic resource saving and environmentally safe renewable heat source that is characterized by inexhaustibility, permanent all the-year-round use, universal prevalence of resources and the ability to replace considerable volumes of traditional energy carriers. The expediency and power efficiency to apply a heat pump with the use of geothermal heat is proved for low-height construction.

  6. CHARACTERIZATION AND COMPARISON OF TREATED AND UNTREATED RICH HUSH ASH & FLY ASH FOR METAL MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    Ravinder Pal Singh

    2011-10-01

    Full Text Available Rice Husk ash and fly ash are agricultural and coal wastes respectively. These are produced in abundance globally and poses risk to health as well as environment. Thus their effective, conducive and eco-friendly utilization has always been a challenge for scientific community. The fly ash has been used as reinforcement for improved mechanical properties of composites (1,3-5,9. Rice husk ash can also be used for similar applications as its composition is almost similar to that of fly ash. This paper mainly deals with identification ofcharacteristics of both the fly ash and rice husk ash using spectroscopic and microscopic analysis. SEM, XRD,XRF and FTIR spectroscopic methods were used for the characterization of treated and untreated ashes. The results were compared and it was observed that both ashes possesses nearly same chemical phases and otherfunctional groups thus proposing the use of rice husk ash as reinforcement like fly ash in Metal Matrix Composites (MMCs specifically for wear resistance applications.

  7. 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.

  8. 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),

  9. 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),

  10. Biology of emerald ash borer parasitoids

    Science.gov (United States)

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

    2015-01-01

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

  11. Fly ash-reinforced thermoplastic starch composites

    Energy Technology Data Exchange (ETDEWEB)

    Ma, X.F.; Yu, J.G.; Wang, N. [Tianjin University, Tianjin (China). School of Science

    2007-01-02

    As a by-product from the combustion of pulverized coal, fly ash was, respectively, used as the reinforcement for formamide and urea-plasticized thermoplastic starch (FUPTPS) and glycerol-plasticized thermoplastic starch (GPTPS). The introduction of fly ash improved tensile stress from 4.56 MPa to 7.78 MPa and Youngs modulus increased trebly from 26.8 MPa to 84.6 MPa for fly ash-reinforced FUPTPS (A-FUPTPS), while tensile stress increased from 4.55 MPa to 12.86 MPa and Youngs modulus increased six times from 76.4 MPa to 545 MPa for fly ash-reinforced GPTPS (A-GPTPS). X-ray diffractograms illustrated that fly ash destroyed the formation of starch ordered crystal structure, so both A-GPTPS and FUPTPS could resist the starch re-crystallization (retrogradation). Also fly ash improved water resistance of TPS. As shown by rheology, during the thermoplastic processing, the extruder screw speed effectively adjusted the flow behavior of A-FUPTPS, while the increasing of the processing temperature effectively ameliorated the flow behavior of A-GPTPS. However, superfluous ash contents (e.g., 20 wt%) worsened processing fluidity and resulted in the congregation of fly ash in FUPTPS matrix (tested by SEM) rather than in GPTPS matrix. This congregation decreased the mechanical properties and water resistance of the materials.

  12. Physicochemical characterization of Spanish fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Querol, X.; Umana, J.C.; Alastuey, A.; Bertrana, C.; Lopez-Soler, A.; Plana, F.

    1999-12-01

    This article summarizes the results obtained from the physical, chemical, and mineralogical characterization of 14 fly ash samples. Major features that influence the utilization of each fly ash for zeolite synthesis are evidenced, and several fly ash types were selected as potential high-quality starting material for zeolite synthesis and ceramic applications. The main parameters influencing this selection were relatively small grain size; high Al and Si contents; high glass content; low CaO, S, and Fe contents; and relatively low heavy metal concentration. The Compostilla and Cou He fly ashes have high potential applications because of the low content of major impurities (such as Ca, Fe, and S) and the low content of soluble hazardous elements. The Espiel, Escucha, Los Barrios, As Pontes, Soto de Ribera, Meirama, Narcea, and Teruel fly ashes have important application potential, but this potential is slightly limited by the intermediate content of nonreactive impurities, such as Fe and Ca. The La Robla fly ash is of moderate interest, since the relatively high Ca and Fe oxide contents may reduce its potential applications. Finally, the Puertollano fly ash also has limited application because of the very high concentration of some heavy metals such as As, Cd, Ge, Hg, Pb, and Zn. From a mineralogical point of view, the Compostilla, Espiel, and Soto de Ribera fly ashes show the highest aluminum-silicate glass content and, consequently, the highest industrial application potential.

  13. Physiochemical characterization of Spanish fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Querol, X.; Umana, J.C.; Alastuey, A.; Bertrana, C.; Lopez Soler, A.; Plana, F.

    1999-12-01

    This article summarizes the results obtained from the physical, chemical, and mineralogical characterization of 14 fly ash samples. Major features that influence the utilization of each fly ash for zeolite synthesis are evidenced, and several fly ash types were selected as potential high-quality starting material for zeolite synthesis and ceramic applications. The main parameters influencing this selection were relatively small grain size; high Al and Si contents; high glass content; low CaO, S, and Fe contents; and relatively low heavy metal concentration. The Compostilla and Dou He fly ashes have high potential applications because of the low content of major impurities (such as Ca, Fe, and S) and the low content of soluble hazardous elements. The Espiel, Escucha, Los Barrios, As Pontes, Soto de Ribera, Meirama, Narcea, and Teruel fly ashes have important application potential, but this potential is slightly limited by the intermediate content of nonreactive impurities, such as Fe and Ca. The La Robla fly ash is of moderate interest, since the relatively high Ca and Fe oxide contents may reduce its potential applications. Finally, the Puertollano fly ash also has limited application because of the very high concentration of some heavy metals such as As, Cd, Ge, Hg, Pb, and Zn. From a mineralogical point of view, the Compostilla, Espiel, and Soto de Ribera fly ashes show the highest aluminum-silicate glass content and, consequently, the highest industrial application potential. (author)

  14. Emerald ash borer biology and invasion history

    Science.gov (United States)

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

    2015-01-01

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

  15. Column leaching from biomass combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard

    2015-01-01

    The utilization of biomass combustion ashes for forest soil liming and fertilizing has been addressed in literature. Though, a deep understanding of the ash chemical composition and leaching behavior is necessary to predict potential benefits and environmental risks related to this practice...

  16. Preparation of heteropolyacid/TiO2/fly-ash-cenosphere photocatalyst for the degradation of ciprofloxacin from aqueous solutions

    Science.gov (United States)

    Wu, Di; Huo, Pengwei; Lu, Ziyang; Gao, Xun; Liu, Xiaolin; Shi, Weidong; Yan, Yongsheng

    2012-07-01

    The TiO2/fly-ash cenosphere photocatalysts modified with heteropolyacid were synthesized by sol-gel followed solvothermal method at 40 °C. Their chemical composition and optical absorption were characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (UV-vis DRS), Fourier Transform Infra Red spectroscopy (FTIR) and Scanning electron microscopy (SEM). It was found that heteropolyacid modification could facilitate the absorption edge of TiO2/fly-ash cenosphere photocatalyst to shift the visible light region. Heteropolyoxanion could be loaded on the titanium dioxide surface, by which could hinder the recombination rate of excited electron holes. The photocatalytic activity of TiO2/fly-ash cenospheres modified with heteropolyacid was observed for the degradation of ciprofloxacin (CPFX) under visible light irradiation. The result from degradation of CPFX suggested that the photocatalytic activity of TiO2/fly-ash cenospheres modified with silicotungstic acid was superior. The synergistic effects of heteropolyacid in modified TiO2/fly-ash cenospheres photocatalyst particles were responsible for improving visible light photocatalytic activity. Besides, the novel photocatalyst was easy to recycle during post treatment because the fly-ash cenosphere was adopted for carrier.

  17. Intestinal solute carriers

    DEFF Research Database (Denmark)

    Steffansen, Bente; Nielsen, Carsten Uhd; Brodin, Birger

    2004-01-01

    A large amount of absorptive intestinal membrane transporters play an important part in absorption and distribution of several nutrients, drugs and prodrugs. The present paper gives a general overview on intestinal solute carriers as well as on trends and strategies for targeting drugs and/or pro...

  18. Autonomous component carrier selection

    DEFF Research Database (Denmark)

    Garcia, Luis Guilherme Uzeda; Pedersen, Klaus; Mogensen, Preben

    2009-01-01

    in local areas, basing our study case on LTE-Advanced. We present extensive network simulation results to demonstrate that a simple and robust interference management scheme, called autonomous component carrier selection allows each cell to select the most attractive frequency configuration; improving...

  19. 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.

  20. 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.

  1. Construction procedures using self hardening fly ash

    Science.gov (United States)

    Thornton, S. I.; Parker, D. G.

    1980-07-01

    Fly ash produced in Arkansas from burning Wyoming low sulfur coal is self-hardening and can be effective as a soil stabilizing agent for clays and sands. The strength of soil-self hardening fly ash develops rapidly when compacted immediately after mixing. Seven day unconfined compressive strengths up to 1800 psi were obtained from 20% fly ash and 80% sand mixtures. A time delay between mixing the fly ash with the soil and compaction of the mixture reduced the strength. With two hours delay, over a third of the strength was lost and with four hours delay, the loss was over half. Gypsum and some commercial concrete retarders were effective in reducing the detrimental effect of delayed compaction. Adequate mixing of the soil and fly ash and rapid compaction of the mixtures were found to be important parameters in field construction of stabilized bases.

  2. Laboratory Studies of Ice Nucleation on Volcanic Ash

    Science.gov (United States)

    Tolbert, M. A.; Schill, G. P.; Genareau, K. D.

    2014-12-01

    Ice nucleation on volcanic ash controls both ash aggregation and cloud glaciation, which affect human respiratory health, atmospheric transport, and global climate. We have performed laboratory studies of the depositional and immersion freezing efficiency of three distinct samples of volcanic ash using Raman Microscopy coupled to an environmental cell. Ash from the Fuego (Basaltic Ash, Guatemala), Soufriere Hills (Andesetic Ash, Montserrat), and Taupo (Rhyolitic Ash, New Zealand) volcanoes were chosen to represent different geographical locations and silica content. All ash samples were quantitatively analyzed for both percent crystallinity and mineralogy using X-ray diffraction. We find that all three samples of volcanic ash are excellent depositional ice nuclei, nucleating ice at ice saturation ratios of 1.05 ± 0.1. For immersion freezing, however, only the Taupo ash exhibited efficient heterogeneous ice nucleation activity. Similar to recent studies on mineral dust, we suggest that the mineralogy of volcanic ash may dictate its ice nucleation activity in the immersion mode.

  3. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    2013-01-08

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

  4. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    2012-05-08

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

  5. The Role of Grain Size and Shape on the Electrical Conductivity of Volcanic Ash

    Science.gov (United States)

    Woods, T.; Genareau, K. D.; Cloer, S.

    2016-12-01

    Volcanic lightning is a common, yet understudied, phenomenon. The exact mechanisms of electric charge generation and transmission in explosive eruption plumes are poorly understood. Ash is a probable charge carrier, and thus, the physical properties of ash may factor into charge generation and transmission. Specifically, the shape and size of ash grains, volatiles bound within the grains, and the efficiency of grains to act as ice nuclei may be contributing factors. To examine the relationship between conductivity and grain size/shape, this research compares conductivity measurements to grain size distribution and shape from five minimally processed ash samples collected from explosive eruptions in Alaska, U.S.A. (Katmai, 1912; Crater Peak, 1992; Augustine, 2006; Okmok, 2008; Redoubt, 2009) that produced volcanic lightning and a set of homogenized (with respect to grain size and shape) ash samples from Lathrop Wells (Nevada, U.S.A.), Taupo (New Zealand), and the Valles Caldera (New Mexico, U.S.A.). Grain size distribution was measured using a laser diffractometer particle size analyzer and grain shapes (aspect ratios, concavity indices) were characterized using backscattered electron images that were processed with ImageJ freeware. The resistance of minimally compressed samples was measured using a current amplifier and converted to conductivity. A general effective media (GEM) equation was then applied using the assumption that the grains are oblate ellipsoids under the influence of minimal compaction. Preliminary analyses suggest that compaction, and therefore shape and contact points, controls ash conductivity and not bulk composition, as homogenized samples provide variable resistance measurements from 1.6 x 10-3 to 9.9 x 10-1 S/m. Non-homogenized Alaskan samples are hypothesized to have higher concavity indices and conductivities when compared to the homogenized samples, due to wider variations in grain size and shape, and these data will be presented.

  6. Synthesis of A type zeolite from rice husk ash; Momigarabai kara no A gata zeolite no gosei

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, K. [Kyushu National Industrial Research Institute, Saga (Japan); Hara, N. [Kagoshima Prefectural Industrial Technology Center, Kagoshima (Japan)

    1995-09-01

    Attempts have been made on synthesizing A-type zeolite from rice husk ash made from burning under different conditions. The rice husk ash (comprising SiO2 at 90 and odd percent) was obtained by heating the rice husk to remove volatile constituents, burning at 350{degree}C to reduce carbon content, and further burning at 400 to 900{degree}C. Soda aluminate and caustic soda were used as additional materials for zeolite. Zeolite was synthesized by so mixing the raw materials that predetermined composition is achieved, adding seed crystals, and heating at 90{degree}C. The result may be summarized as follows: raising the burning temperature reduces the carbon content and increases whiteness of the rice husk ash; dissolution velocity of rice husk ash into NaOH aqueous solution was measured to evaluate the reactivity of the ash (the higher the more preferable); raised burning temperature causes transfer from amorphous state to crystalline state, reducing the dissolution velocity; the lower the burning temperature, the higher the A-type zeolite production rate becomes; whiteness in zeolite is insufficient; preparing water glass from rice husk ash and synthesizing zeolite therefrom achieves high whiteness and high production rate. 6 refs., 4 figs., 2 tabs.

  7. Distribution of charge carriers in dissipative structure of semiconductors

    CERN Document Server

    Kamilov, I K; Kovalev, A S

    2002-01-01

    It has been shown experimentally that redistribution of the charge carrier concentration takes place in the volume of Te and InSb monocrystals under formation and excitation by the strong field of a dissipative structure in nonequilibrium electron-hole plasma. This leads to a situation when the presence of only longitudinal autosolitons in the dissipative structure reduces the charge carrier concentration outside autosolitons while the presence of only transversal autosolitons makes the charge carriers concentration larger. These effects are explained in the following manner: longitudinal autosolitons, occurring in nonequilibrium electron-hole plasma created by the Joule heating are considered as cold and transversal autosolitons are considered as hot ones

  8. Effect of fly ash on the optimum sulfate of Portland Cement

    Science.gov (United States)

    Niemuth, Mark D.

    Calcium sulfate is typically added to ordinary portland cement (OPC) clinker during grinding to prevent flash set and to improve early-age strength development without causing volume instabilities. Recent changes to ASTM C150, Standard Specification for Portland Cement, have enabled greater flexibility in determining optimum sulfate levels in portland cement by not requiring ASTM C563, Approximation of Optimum SO3 in Hydraulic Cement Using Compressive Strength, to be used in setting sulfate target levels. ASTM C563 requires strength testing using only the hydraulic cement, which is not always indicative of the optimum sulfate for field use, since supplementary materials (e.g., fly ash) may be used by the concrete producer. Adding additional sulfate to account for the sulfate demand of fly ashes can enable an improvement in the early age strength for cement-fly ash systems and decrease in problems that may be attributed to OPC-admixture-fly ash incompatibility such as abnormal setting and slow strength gain. This thesis provides experimental data on the strength development and heat release during early hydration for cement-fly ash systems with different sulfate levels. The thesis focused on high calcium fly ashes, but low calcium fly ash was also tested. It is demonstrated that some fly ashes have their own sulfate demand and when these ashes are used in cement-fly ash blends there is effectively an increase in the optimal sulfate level that could be used for the OPC. It is also shown that optimum sulfate determined by heat of hydration measured with isothermal calorimetry is similar to the optimum sulfate determined by compressive strength at 1 day. Using isothermal calorimetry can result in substantial time and cost savings at plants for determining the optimal sulfate content. Theories for the mechanisms that drive the differences in sulfate demand in OPC are reviewed. These theories are adapted for OPC-fly ash blends and are outlined, tested and discussed. The

  9. Ash transformation in suspension fired boilers co-firing coal and straw

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Peter Arendt; Jensen, Anker Degn

    To study the influence of local conditions on the reaction between gaseous KCl and kaolin or coal fly ash experiments were done on CHECs electrically heated entrained flow reactor, which can simulate the local conditions in suspension fired boilers. The experimental results were compared with model...... (1100-1300 °C) or a changed amount of KCl (K/Si = 0.1 – 0.34) did only change the KCl conversion slightly. Si and Al rich coal ash seems to be less efficient to react with KCl compared to kaolin. However the applied coal ash had a larger particle size (d50 = 22μm) compared to the kaolin (d50 = 10μm)....

  10. Fly ash porous material using geopolymerization process for high temperature exposure.

    Science.gov (United States)

    Abdullah, Mohd Mustafa Al Bakri; Jamaludin, Liyana; Hussin, Kamarudin; Bnhussain, Mohamed; Ghazali, Che Mohd Ruzaidi; Ahmad, Mohd Izzat

    2012-01-01

    This paper presents the results of a study on the effect of temperature on geopolymers manufactured using pozzolanic materials (fly ash). In this paper, we report on our investigation of the performance of porous geopolymers made with fly ash after exposure to temperatures from 600 °C up to 1000 °C. The research methodology consisted of pozzolanic materials (fly ash) synthesized with a mixture of sodium hydroxide and sodium silicate solution as an alkaline activator. Foaming agent solution was added to geopolymer paste. The geopolymer paste samples were cured at 60 °C for one day and the geopolymers samples were sintered from 600 °C to 1000 °C to evaluate strength loss due to thermal damage. We also studied their phase formation and microstructure. The heated geopolymers samples were tested by compressive strength after three days. The results showed that the porous geopolymers exhibited strength increases after temperature exposure.

  11. Selective catalytic reduction of NO by ammonia over oil shale ash and fly ash catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Changtao Yue; Shuyuan Li [University of Petroleum, Beijing (China). State Key Lab of Heavy Oil Processing

    2003-07-01

    Acid rain and urban air pollution, produced mainly by pollutants such as SOX and NOX and other volatile organic compounds, has become the most serious environmental problem. The selective catalytic reduction (SCR) of NO with NH{sub 3} in the presence of oxygen is a wellproven method to limit the NOX emissions. The work in this field has been the subject of much research in recent years. In this paper, NO reduction with NH{sub 3} over oil shale ash or fly ash catalysts was studied. Fe, Cu, V or Ni as active elements was loaded by adding aqueous solutions of the metal nitrate over the oil shale ash or fly ash support. The activities of the catalysts for NO removal were measured in a fixed-bed reactor. According to the results, oil shale ash or fly ash, after pre-treatment, can be reasonably used as the SCR catalyst support to remove NO from flue gas. Cu gave the highest catalytic activity and NO conversion for fly ash while V for oil shale ash. As the support, fly ash is more feasible than oil shale ash. Because of their low cost and high efficiency, the catalysts should be used in the SCR process. Further research on this subject is necessary in the future to understand more details of the SCR system and issue of pollution control. 9 refs., 2 figs., 2 tabs.

  12. 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

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

    Directory of Open Access Journals (Sweden)

    Yun-Wang Choi

    2015-01-01

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

  14. The Effect of Lime Addition on the Setting Time and Strength of Ambient Cured Fly Ash Based Geopolymer Binder

    Directory of Open Access Journals (Sweden)

    Adam Andi Arham

    2016-01-01

    Full Text Available One of the limitations of geopolymer as the alternative binders in concrete is the necessity of heat curing. This study aimed to produce fly ash geopolymer binder subjected to ambient curing by adding a small proportion of lime and varying the activator dosage. The Class F fly ash from Mpanau coal-fired power plant was mixed with alkaline solution consists of sodium silicate and sodium hydroxide with Na2O dosage of 5%, 7%, and 9%. To achieve ambient cured paste, 8%, 9%, and 10% slaked lime was added as the substitute for the fly ash. The setting time test was conducted for each mix and the compressive strength was performed at age of 7, 14 and 28 days. The test result shows that the setting time of the fly ash based geopolymer paste can be controlled by adding a small proportion of slaked lime. The addition of lime increased strength but decreased the setting time.

  15. Production of materials with alumina and ashes from incineration of chromium tanned leather shavings: environmental and technical aspects.

    Science.gov (United States)

    Basegio, T; Haas, C; Pokorny, A; Bernardes, A M; Bergmann, C P

    2006-09-21

    The leather tannery industry produces a significant amount of solid and hazardous wastes. Chromium-containing wastes like tanned shavings used to be incinerated in order to recover energy. The incineration process generates ashes that must be disposed of. This paper is a report on the results of the evaluation of technological properties and environmental compatibility of products made of alumina and ashes from incinerated chrome tanned shavings. The raw materials, tannery ashes and alumina were mixed together in different proportions. The ceramic bodies were molded using a hydraulic press and fired with a heating rate of 100 K/h until 1400 degrees C for 4 h in a muffle furnace. The ceramic specimens were characterized regarding physical, mechanical and thermal properties. Leaching tests, according to Brazilian, German and Dutch regulations, were performed on ceramic bodies containing different additions of ash. Results show that the ceramic materials produced are acceptable for refractory applications.

  16. Ash particle erosion on steam boiler convective section

    Energy Technology Data Exchange (ETDEWEB)

    Meuronen, V.

    1997-12-31

    In this study, equations for the calculation of erosion wear caused by ash particles on convective heat exchanger tubes of steam boilers are presented. A new, three-dimensional test arrangement was used in the testing of the erosion wear of convective heat exchanger tubes of steam boilers. When using the sleeve-method, three different tube materials and three tube constructions could be tested. New results were obtained from the analyses. The main mechanisms of erosion wear phenomena and erosion wear as a function of collision conditions and material properties have been studied. Properties of fossil fuels have also been presented. When burning solid fuels, such as pulverized coal and peat in steam boilers, most of the ash is entrained by the flue gas in the furnace. In bubbling and circulating fluidized bed boilers, particle concentration in the flue gas is high because of bed material entrained in the flue gas. Hard particles, such as sharp edged quartz crystals, cause erosion wear when colliding on convective heat exchanger tubes and on the rear wall of the steam boiler. The most important ways to reduce erosion wear in steam boilers is to keep the velocity of the flue gas moderate and prevent channelling of the ash flow in a certain part of the cross section of the flue gas channel, especially near the back wall. One can do this by constructing the boiler with the following components. Screen plates can be used to make the velocity and ash flow distributions more even at the cross-section of the channel. Shield plates and plate type constructions in superheaters can also be used. Erosion testing was conducted with three types of tube constructions: a one tube row, an in- line tube bank with six tube rows, and a staggered tube bark with six tube rows. Three flow velocities and two particle concentrations were used in the tests, which were carried out at room temperature. Three particle materials were used: quartz, coal ash and peat ash particles. Mass loss

  17. LED lamp incorporating remote phosphor with heat dissipation features

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Tao; Letoquin, Ronan; Keller, Bernd; Tarsa, Eric

    2016-11-22

    An LED lamp or bulb is disclosed that comprises a light source, a heat sink structure and a remote planar phosphor carrier having at least one conversion material. The phosphor carrier can be remote to the light sources and mounted to the heat sink so that heat from the phosphor carrier spreads into the heat sink. The phosphor carrier can comprise a thermally conductive transparent material and a phosphor layer, with an LED based light source mounted to the heat sink such that light from the light source passes through the phosphor carrier. At least some of the LED light is converted by the phosphor carrier, with some lamp embodiments emitting a white light combination of LED and phosphor light. The phosphor arranged according to the present invention can operate at lower temperature to thereby operate at greater phosphor conversion efficiency and with reduced heat related damage to the phosphor.

  18. Volcanic Lightning in the Laboratory: The Effect of Ultra-Rapid Melting on Ash Particles

    Science.gov (United States)

    Mueller, S.; Keller, F.; Helo, C.; Buhre, S.; Castro, J. M.

    2016-12-01

    Lightning discharge is a common process occurring at explosive volcanic eruptions. During the formation of ash plumes, the dynamical interaction of ash particles creates charges which can, given a sufficiently large charge gradient, cause lightning discharges within the plume (`plume lightning') or from ground to plume (`near-vent lightning'), respectively. Given the extreme heat release during the short duration of a discharge (potentially > 30.000 K), it is likely that the ash particles suspended in a plume are, in any form, affected by volcanic lightning. Genareau et al. (2015) found evidence of glass spherules and glass aggregates in ash deposits of two explosive eruptions (Eyjafjallajökull, Mt. Redoubt), and linked them to short-term melting processes induced by volcanic lightning (analogue to fulgurites). In order to systematically investigate the potential impact of lightning on air-suspended ash we have designed a new experimental setup. An electric arc between two electrodes is generated by a 400 Amp arc welding device. Ash-sized sample material is then blown into the established lightning arc, and a certain proportion of the injected silicate glasses and/or minerals is melted due to the high temperatures in and around the plasma channel. In a first set of experiments, we have used natural volcanic ash from Laacher See Tephra (Eifel, Germany) in distinct size fractions between 36 and 250 microns, in order to qualitatively investigate melting and amalgamation features. Spherule and aggregate textures similar to those reported by Genareau et al. (2015) were successfully reproduced during these experiments. In a second set of experiments, homogenized phonolitic glass fragments, in different size fractions, were subjected to the electric arc and subsequently analyzed under the EMP, in order to investigate effects of "flash melting" on major element glass chemistry. Genareau K, Wardman JB, Wilson TM, McNutt SR, Izbekov P (2015): Lightning-induced volcanic

  19. Reburning Characteristics of Residual Carbon in Fly Ash from CFB Boilers

    Science.gov (United States)

    Zhang, S. H.; Luo, H. H.; Chen, H. P.; Yang, H. P.; Wang, X. H.

    The content of residual carbon in fly ash of CFB boilers is a litter high especially when low-grade coal, such as lean coal, anthracite coal, gangue, etc. is in service, which greatly influences the efficiency of boilers and fly ash further disposal. Reburn of fly ash through collection, recirculation in CFB furnace or external combustor is a possibly effective strategy to decrease the carbon content, mainly depending on the residual carbon reactivity. In this work, the combustion properties of residual carbon in fly ash and corresponding original coal from large commercial CFB boilers (Kaifeng (440t/h), and Fenyi (410t/h), all in china) are comparably investigated through experiments. The residual carbon involved was firstly extracted and enriched from fly ash by means of floating elutriation to mitigate the influence of ash and minerals on the combustion behavior of residual carbon. Then, the combustion characteristic of two residual carbons and the original coal particles was analyzed with thermogravimetric analyzer (TGA, STA409C from Nestch, Germany). It was observed that the ignition temperature of the residual carbon is much higher than that of original coal sample, and the combustion reactivity of residual carbon is not only dependent on the original coal property, but also the operating conditions. The influence of oxygen content and heating rate was also studied in TGA. The O2 concentration is set as 20%, 30%, 40% and 70% respectively in O2/N2 gas mixture with the flow rate of 100ml/min. It was found that higher oxygen content is favor for decreasing ignition temperature, accelerating the combustion rate of residual carbon. And about 40% of oxygen concentration is experimentally suggested as an optimal value when oxygen-enriched combustion is put into practice for decreasing residual carbon content of fly ash in CFB boilers.

  20. Synthesis and characterization of zeolites prepared from industrial fly ash.

    Science.gov (United States)

    Franus, Wojciech; Wdowin, Magdalena; Franus, Małgorzata

    2014-09-01

    In this paper, we present the possibility of using fly ash to produce synthetic zeolites. The synthesis class F fly ash from the Stalowa Wola SA heat and power plant was subjected to 24 h hydrothermal reaction with sodium hydroxide. Depending on the reaction conditions, three types of synthetic zeolites were formed: Na-X (20 g fly ash, 0.5 dm(3) of 3 mol · dm(-3) NaOH, 75 °C), Na-P1 (20 g fly ash, 0.5 dm(3) of 3 mol · dm(-3) NaOH, 95 °C), and sodalite (20 g fly ash, 0.8 dm(3) of 5 mol · dm(-3) NaOH + 0.4 dm(3) of 3 mol · dm(-3) NaCl, 95 °C). As synthesized materials were characterized to obtain mineral composition (X-ray diffractometry, Scanning electron microscopy-energy dispersive spectrometry), adsorption properties (Brunauer-Emmett-Teller surface area, N2 isotherm adsorption/desorption), and ion exchange capacity. The most effective reaction for zeolite preparation was when sodalite was formed and the quantitative content of zeolite from X-ray diffractometry was 90 wt%, compared with 70 wt% for the Na-X and 75 wt% for the Na-P1. Residues from each synthesis reaction were the following: mullite, quartz, and the remains of amorphous aluminosilicate glass. The best zeolitic material as characterized by highest specific surface area was Na-X at almost 166 m(2) · g(-1), while for the Na-P1 and sodalite it was 71 and 33 m(2) · g(-1), respectively. The ion exchange capacity decreased in the following order: Na-X at 1.8 meq · g(-1), Na-P1 at 0.72 meq · g(-1), and sodalite at 0.56 meq · g(-1). The resulting zeolites are competitive for commercially available materials and are used as ion exchangers in industrial wastewater and soil decontamination.

  1. Pozzolanic Reaction Kinetics of Coal Ashes

    Institute of Scientific and Technical Information of China (English)

    ZHENG Hongwei; WANG Zhijuan; QIAN Jueshi; SONG Yuanming; WANG Zhi

    2009-01-01

    The pozzolanic reactivity was determined by the hydration kinetics of pozzolanic reaction based on the fact that the hydration products of active SiO_2 and Al_2O_3 with lime were soluble in dilute hydrochloric acid.The results show that the pozzolanic reaction of active SiO_2 and Al2O3 of coal ashes follows apparent first-order kinetics.The reaction rate constant of FBC ashes is greater than that of PC ashes,while the activation energy of the former is lower than that of the latter.It is confirmed that the pozzolanic activity of fluidized bed combustion(FBC)ashes is significantly higher than that of PC ashes,and the reaction barrier of the former is lower than that of the latter,because the microstructures of FBC ashes,such as mineralogical composition,morphology and polymerization degree of [SiO_4]and[AlO_6]are more favorable to the pozzolanic activity development than those of PC ashes.

  2. The climatic impact of supervolcanic ash blankets

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Morgan T.; Sparks, R.S.J. [University of Bristol, Department of Earth Sciences, Bristol (United Kingdom); Valdes, Paul J. [University of Bristol, School of Geographical Sciences, Bristol (United Kingdom)

    2007-11-15

    Supervolcanoes are large caldera systems that can expel vast quantities of ash, volcanic gases in a single eruption, far larger than any recorded in recent history. These super-eruptions have been suggested as possible catalysts for long-term climate change and may be responsible for bottlenecks in human and animal populations. Here, we consider the previously neglected climatic effects of a continent-sized ash deposit with a high albedo and show that a decadal climate forcing is expected. We use a coupled atmosphere-ocean General Circulation Model (GCM) to simulate the effect of an ash blanket from Yellowstone volcano, USA, covering much of North America. Reflectivity measurements of dry volcanic ash show albedo values as high as snow, implying that the effects of an ash blanket would be severe. The modeling results indicate major disturbances to the climate, particularly to oscillatory patterns such as the El Nino Southern Oscillation (ENSO). Atmospheric disruptions would continue for decades after the eruption due to extended ash blanket longevity. The climatic response to an ash blanket is not significant enough to investigate a change to stadial periods at present day boundary conditions, though this is one of several impacts associated with a super-eruption which may induce long-term climatic change. (orig.)

  3. Marine mesocosm bacterial colonisation of volcanic ash

    Science.gov (United States)

    Witt, Verena; Cimarelli, Corrado; Ayris, Paul; Kueppers, Ulrich; Erpenbeck, Dirk; Dingwell, Donald; Woerheide, Gert

    2015-04-01

    Volcanic eruptions regularly eject large quantities of ash particles into the atmosphere, which can be deposited via fallout into oceanic environments. Such fallout has the potential to alter pH, light and nutrient availability at local scales. Shallow-water coral reef ecosystems - "rainforests of the sea" - are highly sensitive to disturbances, such as ocean acidification, sedimentation and eutrophication. Therefore, wind-delivered volcanic ash may lead to burial and mortality of such reefs. Coral reef ecosystem resilience may depend on pioneer bacterial colonisation of the ash layer, supporting subsequent establishment of the micro- and ultimately the macro-community. However, which bacteria are involved in pioneer colonisation remain unknown. We hypothesize that physico-chemical properties (i.e., morphology, mineralogy) of the ash may dictate bacterial colonisation. The effect of substrate properties on bacterial colonisation was tested by exposing five substrates: i) quartz sand ii) crystalline ash (Sakurajima, Japan) iii) volcanic glass iv) carbonate reef sand and v) calcite sand of similar grain size, in controlled marine coral reef aquaria under low light conditions for six months. Bacterial communities were screened every month by Automated Ribosomal Intergenic Spacer Analysis of the 16S-23S rRNA Internal Transcribed Spacer region. Multivariate statistics revealed discrete groupings of bacterial communities on substrates of volcanic origin (ash and glass) and reef origin (three sands). Analysis of Similarity supported significantly different communities associated with all substrates (p=0.0001), only quartz did not differ from both carbonate and calcite sands. The ash substrate exhibited the most diverse bacterial community with the most substrate-specific bacterial operational taxonomic units. Our findings suggest that bacterial diversity and community composition during colonisation of volcanic ash in a coral reef-like environment is controlled by the

  4. Development of Passenger Air Carriers

    Directory of Open Access Journals (Sweden)

    Igor Diminik

    2006-09-01

    Full Text Available The work presents the development of carriers in passengerair traffic, and the focus is on the development and operationsof carriers in chartered passenger transport. After the SecondWorld War, there were only scheduled air carriers. The need formass transport of tourists resulted in the development of chartercarriers or usage of scheduled carriers under different commercialconditions acceptable for tourism. Eventually also low-costcarriers appeared and they realize an increasing share in thepassenger transport especially in the aviation developed countries.

  5. Gettering improvements of minority-carrier lifetimesin solar grade silicon

    DEFF Research Database (Denmark)

    Osinniy, Viktor; Nylandsted Larsen, Arne; Dahl, Espen;

    2012-01-01

    processes. Optimal heat-treatment parameters for each group of samples were then identified which improved the minority-carrier lifetimes to values higher than the minimum value needed for solar cells. Phosphorus gettering using a variable temperature process enhanced in particular the lifetime within each......The minority-carrier lifetime in p-type solar-grade silicon (SoG-Si) produced by Elkem Solar was investigated after different types of heat treatment. Two groups of samples differing by the as-grown lifetimes were exposed to internal and phosphorus gettering using constant and variable temperature...

  6. Utilisation of zeolitised coal fly ash as immobilising agent of a metallurgical waste

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Pereira, C.; Galiano, Y.L.; Rodriguez-Pinero, M.A.; Vale, J.; Querol, X. [University of Sevilla, Seville (Spain). Dept. Ingenieria Quimica y Ambiental, Escuela Superior Ingenieros Industriales

    2002-07-01

    Partially zeolitised coal fly ash from a Spanish power station has been studied as the immobilising agent of an arc furnace dust waste (s-WA). The hazardous metals normally found in this kind of waste are lead, cadmium, and chromium. In addition, the dust usually has a high zinc content resulting from the use of galvanised scrap. Because of its heavy metal content, s-WA is classified as hazardous waste, according to Spanish regulations. Different zeolitisation procedures, depending on the treatment of the fly ash with NaOH and KOH alkaline solutions, using reflux heating and different times of attack were tested. The zeolitised products were studied using XRD in order to characterise the solid phases produced. The solidification/stabilisation (S/S) trials of s-WA were carried out using the zeolitised ashes, as well as the original coal fly ash, in mixtures containing 20% (w/w) of ordinary Portland cement. To evaluate the efficiency of the immobilisation process, some specific criteria were defined, with regard to some physical (compressive strength) and chemical (pH and metal concentrations in TCLP leachates) characteristics of the S/S solids. Finally, comparisons among the stabilising mixtures were made and the role of the zeolitisation of fly ash in the S/S process was evaluated.

  7. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  8. Fly Ash Disposal in Ash Ponds: A Threat to Ground Water Contamination

    Science.gov (United States)

    Singh, R. K.; Gupta, N. C.; Guha, B. K.

    2016-07-01

    Ground water contamination due to deposition of fly ash in ash ponds was assessed by simulating the disposal site conditions using batch leaching test with fly ash samples from three thermal power plants. The periodic analysis of leachates was performed for selected elements, Fe, Cu, Ni, Cr, Pb and Cd in three different extraction solutions to determine the maximum amount that can be leached from fly ash. It was observed that at low pH value, maximum metals are released from the surface of the ash into leachate. The average concentration of these elements found in ground water samples from the nearby area of ash ponds shows that almost all the metals except `Cr' are crossing the prescribed limits of drinking water. The concentration of these elements at this level can endanger public health and environment.

  9. Fly Ash Disposal in Ash Ponds: A Threat to Ground Water Contamination

    Science.gov (United States)

    Singh, R. K.; Gupta, N. C.; Guha, B. K.

    2016-09-01

    Ground water contamination due to deposition of fly ash in ash ponds was assessed by simulating the disposal site conditions using batch leaching test with fly ash samples from three thermal power plants. The periodic analysis of leachates was performed for selected elements, Fe, Cu, Ni, Cr, Pb and Cd in three different extraction solutions to determine the maximum amount that can be leached from fly ash. It was observed that at low pH value, maximum metals are released from the surface of the ash into leachate. The average concentration of these elements found in ground water samples from the nearby area of ash ponds shows that almost all the metals except `Cr' are crossing the prescribed limits of drinking water. The concentration of these elements at this level can endanger public health and environment.

  10. Effect of Fly Ash on the Electrical Conductivity of Concretes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The fly ash occasionally has high content of iron oxide and carbon that are good electrical conducting components. This paper investigates the effect of the fly ash used as mineral admixtures on the electrical conductivity of concretes. The electrical properties of concretes using 3 kinds of fly ash with different iron oxide contents have been studied. Experimental results show that at the same fly ash dosage the resistivity of concrete using fly ash with high content of iron oxide is slightly lower than that with low content of iron oxide. However, the concrete resistivity after 14d increases as fly ash dosage increases regardless of iron oxide content in fly ash.

  11. 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

  12. Volcanic particle aggregation in explosive eruption columns. Part I: Parameterization of the microphysics of hydrometeors and ash

    Science.gov (United States)

    Textor, C.; Graf, H. F.; Herzog, M.; Oberhuber, J. M.; Rose, William I.; Ernst, G. G. J.

    2006-02-01

    The aggregation of volcanic ash particles within the eruption column of explosive eruptions has been observed at many volcanoes. It influences the residence time of ash in the atmosphere and the radiative properties of the umbrella cloud. However, the information on the processes leading to aggregate formation are still either lacking or very incomplete. We examine the fate of ash particles through numerical experiments with the plume model ATHAM (Active Tracer High resolution Atmospheric Model) in order to determine the conditions that promote ash particle aggregation. In this paper we describe the microphysics and parameterization of ash and hydrometeors. In a companion paper (this issue) we use this information in a series of numerical experiments. The parameterization includes the condensation of water vapor in the rising eruption column. The formation of liquid and solid hydrometeors and the effect of latent heat release on the eruption column dynamics are considered. The interactions of hydrometeors and volcanic ash within the eruption column that lead to aggregate formation are simulated for the first time within a rising eruption column. The microphysical parameterization follows a modal approach. The hydrometeors are described by two size classes, each of which is divided into a liquid and a frozen category. By analogy with the hydrometeor classification, we specify four categories of volcanic ash particles. We imply that volcanic particles are active as condensation nuclei for water and ice formation. Ash can be contained in all categories of hydrometeors, thus forming mixed particles of any composition reaching from mud rain to accretionary lapilli. Collisions are caused by gravitational capture of particles with different fall velocity. Coalescence of hydrometeor-ash aggregates is assumed to be a function of the hydrometeor mass fraction within the mixed particles. The parameterization also includes simplified descriptions of electrostatics and salinity

  13. Effect of Fly Ash and Silica Fume on Hydration Rate of Cement Pastes and Strength of Mortars

    Institute of Scientific and Technical Information of China (English)

    LIU Jun; ZHANG Yun; LIU Runqing; ZHANG Bing

    2014-01-01

    The effect of fly ash and silica fume on hydration rate and strength of cement in the early stage was studied. Contrast test was applied to the complex cementitious system to investigate the hydration rate. Combined with mechanical strength, the influence of fly ash and silica fume during the hydration process of complex binder was researched. The peak of the rate of hydration heat evolution and the mechanical strength decreased as the ratio of fly ash increased, however, as the ratio of silica fume increased, the peak of the rate of hydration heat evolution and the mechanical strength increased obviously. When the ratios of fly ash and silica fume are 10%and 5%, the peak of the rate of hydration heat evolution is the highest. At the same time 7 days of flexural and compressive strength are the highest as 8.89 MPa and 46.52 MPa, respectively. Fly ash and silica fume are the main factors affecting the hydration rate and the mechanical property.

  14. Biomass fly ash in concrete: Mixture proportioning and mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Shuangzhen Wang; Amber Miller; Emilio Llamazos; Fernando Fonseca; Larry Baxter [Brigham Young University, Provo, UT (USA). Department of Chemical Engineering

    2008-03-15

    ASTM C 618 prohibits use of biomass fly ashes in concrete. This document compares the properties of biomass fly ashes from cofired (herbaceous with coal), pure wood combustion and blended (pure wood fly ash blended with coal fly ash) to those of coal fly ash in concrete. The results illustrate that with 25% replacement (wt%) of cement by fly ash, the compressive strength (one day to one year) and the flexure strength (at 56th day curing) of cofired and blended biomass fly ash concrete is statistically equal to that of two coal fly ash concrete in this investigation (at 95% confidence interval). This implies that biomass fly ash with co-firing concentration within the concentration interest to commercial coal-biomass co-firing operations at power plants and blended biomass fly ash within a certain blending ratio should be considered in concrete. 37 refs., 10 figs., 2 tabs.

  15. Rice Husk Ash Derived Zeolite Blended with Water Hyacinth Ash for Enhanced Adsorption of Cadmium Ions

    OpenAIRE

    G. W. Mbugua; H. M. Mbuvi; J. W. Muthengia

    2014-01-01

    In order to helpcurtail or imposesustained control to the offensive water hyacinth plant,it is essential to explore ways of generatingwater remediation materials from it. In the current study, the capacity and efficacy of water hyacinth ash (WHA),its insoluble residue (WHAR) and rice husk ash (RHA)to remove cadmium ionsand methylene blue from contaminated water was investigated. Mixtures of the two ashes were used to formulatezeolitic materialsby hydrothermal reactions. Material A, ZMA was pr...

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

    Science.gov (United States)

    Kathleen S. Knight

    2014-01-01

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

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

    DEFF Research Database (Denmark)

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

    2003-01-01

    Electrodialytic Remediation has recently been suggested as a potential method for removal of heavy metals from fly ashes. In this work electrodialytic remediation of three different fly ashes, i.e. two municipal solid waste incinerator (MSWI) fly ashes and one wood combustion fly ash was studied...

  18. Fluidized bed gasification ash reduction and removal process

    Science.gov (United States)

    Schenone, Carl E.; Rosinski, Joseph

    1984-12-04

    In a fluidized bed gasification system an ash removal system to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

  19. Fluidized bed gasification ash reduction and removal system

    Science.gov (United States)

    Schenone, Carl E.; Rosinski, Joseph

    1984-02-28

    In a fluidized bed gasification system an ash removal system to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

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

    Science.gov (United States)

    Chen, Yigen; Poland, Therese M

    2009-12-01

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

  1. The heat exchanger of small pellet boiler for phytomass

    Science.gov (United States)

    Mičieta, Jozef; Lenhard, Richard; Jandačka, Jozef

    2014-08-01

    Combustion of pellets from plant biomass (phytomass) causes various troubles. Main problem is slagging ash because of low melting temperature of ash from phytomass. This problem is possible to solve either improving energetic properties of phytomass by additives or modification of boiler construction. A small-scale boiler for phytomass is different in construction of heat exchanger and furnace mainly. We solve major problem - slagging ash, by decreasing combustion temperature via redesign of pellet burner and boiler body. Consequence of lower combustion temperature is also lower temperature gradient of combustion gas. It means that is necessary to design larger heat exchanging surface. We plane to use underfed burner, so we would utilize circle symmetry heat exchanger. Paper deals design of heat exchanger construction with help of CFD simulation. Our purpose is to keep uniform water flux and combustion gas flux in heat exchanger without zone of local overheating and excess cooling.

  2. Maintainable substrate carrier for electroplating

    Science.gov (United States)

    Chen, Chen-An [Milpitas, CA; Abas, Emmanuel Chua [Laguna, PH; Divino, Edmundo Anida [Cavite, PH; Ermita, Jake Randal G [Laguna, PH; Capulong, Jose Francisco S [Laguna, PH; Castillo, Arnold Villamor [Batangas, PH; Ma,; Xiaobing, Diana [Saratoga, CA

    2012-07-17

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.

  3. Maintainable substrate carrier for electroplating

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chen-An; Abas, Emmanuel Chua; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor; Ma, Diana Xiaobing

    2016-08-02

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.

  4. Recycling of ash from mezcal industry: a renewable source of lime.

    Science.gov (United States)

    Chávez-Guerrero, L; Flores, J; Kharissov, B I

    2010-10-01

    Agave bagasse is a byproduct generated in the mezcal industry. Normally it is burned to reduce its volume, then a byproduct is generated in the form of residual ash, which can contaminate the water in rivers and lakes near the production places called "mezcaleras". This report details measurements of the Agave Salmiana fiber transformation after the burning process. The wasted ash was heated at 950°C, and then hydrolyzed. The compounds were indentified using the X-ray diffraction. The images obtained by scanning electron microscope showed all the morphological transformations of the lime through the whole process. Thermal, elemental and morphological characterization of the agave bagasse were done. Experiments showed that 16% of ash was produced in the burning process of agave bagasse (450°C), and 66% of the ash remains after heating (950°C) in the form of calcium oxide. The results show an important renewable source of calcium compounds, due to the high production of agave based beverages in México. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. AshMeadowsSpeckledDace_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 Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  6. AshMeadowsAmargosaPupfish_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 Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  7. Cementing Properties of Oil Shale Ash

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The oil crisis has prompted renewed interest in direct burning of oil shale as an alternative energy source.A major problem in this process is the large portion of ash produced.The cementing properties of this ash were investigated to determine its applicability as a building material.By means of XRD, IR, NMR and ICP, we have studied the effects of burning temperature on the reactivity of ash.Maximum reactivity was obtained with ash samples produced at 700 °C to 900 °C.In this range, the strength of oil-shale-based material, with properties similar to cement, which is composed of oil shale and several other kinds of solid wastes, can achieve the standard of 42.5# cement.Our study has provided an experimental foundation and theoretical base for a massive utilization of oil shale.

  8. Volcanic Ash Advisory Database, 1983-2003

    Data.gov (United States)

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

  9. ASH External Web Portal (External Portal) -

    Data.gov (United States)

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

  10. AshMeadowsSpeckledDace_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 Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  11. AshMeadowsAmargosaPupfish_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 Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  12. Clay Improvement with Burned Olive Waste Ash

    Directory of Open Access Journals (Sweden)

    Utkan Mutman

    2013-01-01

    Full Text Available Olive oil is concentrated in the Mediterranean basin countries. Since the olive oil industries are incriminated for a high quantity of pollution, it has become imperative to solve this problem by developing optimized systems for the treatment of olive oil wastes. This study proposes a solution to the problem. Burned olive waste ash is evaluated for using it as clay stabilizer. In a laboratory, bentonite clay is used to improve olive waste ash. Before the laboratory, the olive waste is burned at 550°C in the high temperature oven. The burned olive waste ash was added to bentonite clay with increasing 1% by weight from 1% to 10%. The study consisted of the following tests on samples treated with burned olive waste ash: Atterberg Limits, Standard Proctor Density, and Unconfined Compressive Strength Tests. The test results show promise for this material to be used as stabilizer and to solve many of the problems associated with its accumulation.

  13. Hydrogen: the future energy carrier.

    Science.gov (United States)

    Züttel, Andreas; Remhof, Arndt; Borgschulte, Andreas; Friedrichs, Oliver

    2010-07-28

    Since the beginning of the twenty-first century the limitations of the fossil age with regard to the continuing growth of energy demand, the peaking mining rate of oil, the growing impact of CO2 emissions on the environment and the dependency of the economy in the industrialized world on the availability of fossil fuels became very obvious. A major change in the energy economy from fossil energy carriers to renewable energy fluxes is necessary. The main challenge is to efficiently convert renewable energy into electricity and the storage of electricity or the production of a synthetic fuel. Hydrogen is produced from water by electricity through an electrolyser. The storage of hydrogen in its molecular or atomic form is a materials challenge. Some hydrides are known to exhibit a hydrogen density comparable to oil; however, these hydrides require a sophisticated storage system. The system energy density is significantly smaller than the energy density of fossil fuels. An interesting alternative to the direct storage of hydrogen are synthetic hydrocarbons produced from hydrogen and CO2 extracted from the atmosphere. They are CO2 neutral and stored like fossil fuels. Conventional combustion engines and turbines can be used in order to convert the stored energy into work and heat.

  14. Methanol as an energy carrier

    Energy Technology Data Exchange (ETDEWEB)

    Biedermann, P.; Grube, T.; Hoehlein, B. (eds.)

    2006-07-01

    For the future, a strongly growing energy demand is expected in the transport sector worldwide. Economically efficient oil production will run through a maximum in the next decade. Higher fuel prices and an environmentally desirable reduction of emissions will increase the pressure for reducing fuel consumption and emissions in road traffic. These criteria show the urgent necessity of structural changes in the fuel market. Due to its advantages concerning industrial-scale production, storage and global availability, methanol has the short- to medium-term potential for gaining increased significance as a substitution product in the energy market. Methanol can be produced both from fossil energy sources and from biomass or waste materials through the process steps of synthesis gas generation with subsequent methanol synthesis. Methanol has the potential to be used in an environmentally friendly manner in gasoline/methanol mixtures for flexible fuel vehicles with internal combustion engines and in diesel engines with pure methanol. Furthermore, it can be used in fuel cell vehicles with on-board hydrogen production in direct methanol fuel cell drives, and in stationary systems for electricity and heat generation as well as for hydrogen production. Finally, in portable applications it serves as an energy carrier for electric power generation. In this book, the processes for the production and use of methanol are presented and evaluated, markets and future options are discussed and issues of safety and environmental impacts are addressed by a team of well-known authors. (orig.)

  15. Characterization of fine volcanic ash from explosive eruption from Sakurajima volcano, South Japan

    Science.gov (United States)

    Nanayama, F.; Furukawa, R.; Ishizuka, Y.; Yamamoto, T.; Geshi, N.; Oishi, M.

    2013-12-01

    distributions of volcanic ash from Sakurajima volcano have basically characteristics of unimodal and gaussian. Mode of distributions are 150 - 200 micron at 5 km and 70-80 micron at 20 km respectively from the Showa crater. Mode and deviation of the grain size distribution are function of distance from the source. Fine volcanic ash less than 1 micron in diameter is few and exists in every samples. Component of volcanic ash samples are dark-colored dense glass shard (ca. 50%), light-colored dense glass shard (10%), variously colored and vesiculated glass shard (10%), free crystal (20%), lithic fragment (10%), and altered fragment (less than 5%) which are mostly having similar ratio in every location suggesting single source process of the eruption. We also found fine volcanic ash samples less than 10 micron are frequently aggregated. The present study includes the result of "Research and Development of Margin Assessment Methodology of Decay Heat Removal Function against External Hazards" entrusted to Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT).

  16. 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

  17. Glycosylation of solute carriers

    DEFF Research Database (Denmark)

    Pedersen, Nis Borbye; Carlsson, Michael C; Pedersen, Stine Helene Falsig

    2016-01-01

    as their posttranslational regulation, but only relatively little is known about the role of SLC glycosylation. Glycosylation is one of the most abundant posttranslational modifications of animal proteins and through recent advances in our understanding of protein-glycan interactions, the functional roles of SLC......Solute carriers (SLCs) are one of the largest groups of multi-spanning membrane proteins in mammals and include ubiquitously expressed proteins as well as proteins with highly restricted tissue expression. A vast number of studies have addressed the function and organization of SLCs as well...

  18. 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.

  19. 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.

  20. Particle sedimentation and diffusive convection in volcanic ash-clouds

    Science.gov (United States)

    Carazzo, G.; Jellinek, A. M.

    2013-04-01

    Understanding the longevity of volcanic ash-clouds generated by powerful explosive eruptions is a long standing problem for assessing volcanic hazards and the nature and time scale of volcanic forcings on climate change. It is well known that the lateral spreading and longevity of these clouds is influenced by stratospheric winds, particle settling and turbulent diffusion. Observations of the recent 2010 Eyjafjallajökull and 2011 Grimsvötn umbrella clouds, as well as the structure of atmospheric aerosol clouds from the 1991 Mt Pinatubo event, suggest that an additional key process governing the cloud dynamics is the production of internal layering. Here, we use analog experiments on turbulent particle-laden umbrella clouds to show that this layering occurs where natural convection driven by particle sedimentation and the differential diffusion of primarily heat and fine particles give rise to a large scale instability. Where umbrella clouds are particularly enriched in fine ash, this "particle diffusive convection" strongly influences the cloud longevity. More generally, cloud residence time will depend on fluxes due to both individual settling and diffusive convection. We develop a new sedimentation model that includes both sedimentation processes, and which is found to capture real-time measurements of the rate of change of particle concentration in the 1982 El Chichon, 1991 Mt Pinatubo and 1992 Mt Spurr ash-clouds. A key result is that these combined sedimentation processes enhance the fallout of fine particles relative to expectations from individual settling suggesting that particle aggregation is not the only mechanism required to explain volcanic umbrella longevity.

  1. Ash Shutbah: A possible impact structure in Saudi Arabia

    Science.gov (United States)

    Gnos, Edwin; Hofmann, Beda A.; Schmieder, Martin; Al-Wagdani, Khalid; Mahjoub, Ayman; Al-Solami, Abdulaziz A.; Habibullah, Siddiq N.; Matter, Albert; Alwmark, Carl

    2014-10-01

    We have investigated the Ash Shutbah circular structure in central Saudi Arabia (21°37'N 45°39'E) using satellite imagery, field mapping, thin-section petrography, and X-ray diffraction of collected samples. The approximately 2.1 km sized structure located in flat-lying Jurassic Tuwaiq Mountain Limestone has been nearly peneplained by erosional processes. Satellite and structural data show a central area consisting of Dhruma Formation sandstones with steep bedding and tight folds plunging radially outward. Open folding occurs in displaced, younger Tuwaiq Mountain Limestone Formation blocks surrounding the central area, but is absent outside the circular structure. An approximately 60 cm thick, unique folded and disrupted orthoquartzitic sandstone marker bed occurring in the central area of the structure is found 140 m deeper in undisturbed escarpment outcrops located a few hundred meters west of the structure. With exception of a possible concave shatter cone found in the orthoquartzite of the central area, other diagnostic shock features are lacking. Some quartz-rich sandstones from the central area show pervasive fracturing of quartz grains with common concussion fractures. This deformation was followed by an event of quartz dissolution and calcite precipitation consistent with local sea- or groundwater heating. The combination of central stratigraphic uplift of 140 m, concussion features in discolored sandstone, outward-dipping concentric folds in the central area, deformation restricted to the rocks of the ring structure, a complex circular structure of 2.1 km diameter that appears broadly consistent with what one would expect from an impact structure in sedimentary targets, and a possible shatter cone all point to an impact origin of the Ash Shutbah structure. In fact, the Ash Shutbah structure appears to be a textbook example of an eroded, complex impact crater located in flat-lying sedimentary rocks, where the undisturbed stratigraphic section can be

  2. Effects of ash forming temperature on water-soluble fraction of biomass ash and it’s elements%成灰温度对三种生物质灰及其元素水溶性的影响

    Institute of Scientific and Technical Information of China (English)

    何芳; 于如军; 张毅; 朱继英; 高振强; 孙鹏

    2015-01-01

    The implementation of biomass ash as a fertilizer is beneficial to the sustainable development of agriculture because it can return the elements taken by the plants from soil during the growth. Water solubility of biomass ash together with its elements is a vital property for the fertilizer’s utilization. In this paper, the effects of ash forming temperature on the water solubility of biomass ash and its elements were investigated experimentally. Three typical types of agro-residues in China, i.e. wheat straw, corn stover and rice husk, were chosen for investigation. Materials were collected and the corresponding proximate and elemental analyses were performed. In preparation process, wheat straw and corn stover were milled into powder with the particle size of less than 1 mm. Ashes were prepared in a muffle furnace at different ash forming temperatures in the scope from 400 to 800℃with the temperature interval of 50℃. About 4-5 g of each sample powder and rice husk were put in the crucibles, heated from ambient temperature to ash forming temperature, and then kept at the ash forming temperature for 4 hours in the muffle furnace. After the temperature of the furnace dropped to less than 200℃, the ashes were taken out to the cabinet dryer, cooled to the ambient temperature, and then weighted and sealed in the sample bag for further measurements. It showed that ash contents of wheat straw, corn stover and rice husk decreased significantly with the increase of ash forming temperature. They decreased from 9.8%, 10.9%and 18.4% at 400℃to 6.9%, 8.7%and 16.8%at 800℃respectively. After the preparation of all the ash, two types of measurements were performed. The first was the water solubility measurement of the ashes according to the standard of GB8307-2002. Total ash of about 0.2-0.3 g was put in a beaker of 50 ml and about 25 ml distilled water was added in it. The mixture was heated and boiled for 2 min and then the solution was filtered through a

  3. Aviation response to a widely dispersed volcanic ash and gas cloud from the August 2008 eruption of Kasatochi, Alaska, USA

    Science.gov (United States)

    Guffanti, Marianne; Schneider, David J.; Wallace, Kristi L.; Hall, Tony; Bensimon, Dov R.; Salinas, Leonard J.

    2010-01-01

    The extensive volcanic cloud from Kasatochi's 2008 eruption caused widespread disruptions to aviation operations along Pacific oceanic, Canadian, and U.S. air routes. Based on aviation hazard warnings issued by the National Oceanic and Atmospheric Administration, U.S. Geological Survey, the Federal Aviation Administration, and Meteorological Service of Canada, air carriers largely avoided the volcanic cloud over a 5 day period by route modifications and flight cancellations. Comparison of time coincident GOES thermal infrared (TIR) data for ash detection with Ozone Monitoring Instrument (OMI) ultraviolet data for SO2 detection shows congruent areas of ash and gas in the volcanic cloud in the 2 days following onset of ash production. After about 2.5 days, the area of SO2 detected by OMI was more extensive than the area of ash indicated by TIR data, indicating significant ash depletion by fall out had occurred. Pilot reports of visible haze at cruise altitudes over Canada and the northern United States suggested that SO2 gas had converted to sulfate aerosols. Uncertain about the hazard potential of the aging cloud, airlines coped by flying over, under, or around the observed haze layer. Samples from a nondamaging aircraft encounter with Kasatochi's nearly 3 day old cloud contained volcanic silicate particles, confirming that some fine ash is present in predominantly gas clouds. The aircraft's exposure to ash was insufficient to cause engine damage; however, slightly damaging encounters with volcanic clouds from eruptions of Reventador in 2002 and Hekla in 2000 indicate the possibility of lingering hazards associated with old and/or diffuse volcanic clouds.

  4. Ash Deposit Formation and Removal in a Straw and Wood Suspension-Fired Boiler

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming

    Utilization of biomass on large suspension-fired boilers is a potentially efficient method to reduce net CO2 emissions and reduce the consumption of fossil fuels. However, ash deposit formation on heat transfer surfaces may cuase operational problems and in severe cases lead to boiler stop...... and manual cleaning. Most studies on ash deposition and removal has been done on biomass grate boilers, while only limited data is available from biomass suspension-firing. The aim of this study was to investigate deposit mass uptake, heat uptake reduction, deposit characteristics, and deposit removal...... scale experimental studies conducted by CHEC indicated that there was not a big difference regarding final deposit mass uptake during straw suspension-firing and combustion on grate. The shedding (deposit removal) events were investigated when the nearby plant sootblower was shutdown. It was identified...

  5. Scale-Up and Demonstration of Fly Ash Ozonation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Rui Afonso; R. Hurt; I. Kulaots

    2006-03-01

    The disposal of fly ash from the combustion of coal has become increasingly important. When the fly ash does not meet the required specification for the product or market intended, it is necessary to beneficiate it to achieve the desired quality. This project, conducted at PPL's Montour SES, is the first near full-scale ({approx}10 ton/day), demonstration of ash ozonation technology. Bituminous and sub bituminous ashes, including two ash samples that contained activated carbon, were treated during the project. Results from the tests were very promising. The ashes were successfully treated with ozone, yielding concrete-suitable ash quality. Preliminary process cost estimates indicate that capital and operating costs to treat unburned carbon are competitive with other commercial ash beneficiation technologies at a fraction of the cost of lost sales and/or ash disposal costs. This is the final technical report under DOE Cooperative Agreement No.: DE-FC26-03NT41730.

  6. Ash transformation during co-firing coal and straw

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Peter Arendt; Jensen, Anker Degn;

    2007-01-01

    Co-firing straw with coal in pulverized fuel boilers can cause problems related to fly ash utilization, deposit formation, corrosion and SCR catalyst deactivation due to the high contents of Cl and K in the ash. To investigate the interaction between coal and straw ash and the effect of coal...... quality on fly ash and deposit properties, straw was co-fired with three kinds of coal in an entrained flow reactor. The compositions of the produced ashes were compared to the available literature data to find suitable scaling parameters that can be used to predict the composition of ash from straw...... importantly, by reaction with Al and Si in the fly ash. About 70-80% K in the fly ash appears as alumina silicates while the remainder K is mainly present as sulphate. Lignite/straw co-firing produces fly ash with relatively high Cl content. This is probably because of the high content of calcium...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-11-01

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

  8. Modeling calcium dissolution from oil shale ash: Part 2.. Continuous washing of the ash layer

    Energy Technology Data Exchange (ETDEWEB)

    Velts, O.; Kallas, J. [Tallinn University of Technology, Laboratory of Inorganic Materials, 5 Ehitajate Str., Tallinn 19086 (Estonia); Lappeenranta University of Technology, Laboratory of Separation Technology, Skinnarilankatu 34, Lappeenranta 53851 (Finland); Hautaniemi, M.; Kuosa, M. [Lappeenranta University of Technology, Laboratory of Separation Technology, Skinnarilankatu 34, Lappeenranta 53851 (Finland); Kuusik, R. [Tallinn University of Technology, Laboratory of Inorganic Materials, 5 Ehitajate Str., Tallinn 19086 (Estonia)

    2010-05-15

    In the present work a possible approach to the utilization of oil shale ash containing free lime in precipitated calcium carbonate (PCC) production is elucidated. This paper investigates the Ca (calcium) dissolution process during continuous washing of pulverized firing (PF) and fluidized bed combustion (FBC) oil shale ash layers in a packed-bed leaching column. The main characteristics of the Ca dissolution process from ash are established. The effect of water flow rate is investigated by conducting leaching experiments of oil shale ashes formed in boilers operating with different combustion technologies. The values of the overall and liquid phase mass transfer coefficients are evaluated based on experiments using the developed ash layer washing model. The model is a set of partial differential equations that describe the changes in Ca content in the stagnant layer of ash and in the water flowing through the ash layer. An example in which the model is applied to environmental assessment and estimation of Ca leaching from industrial oil shale ash fields is provided. (author)

  9. 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.

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

    Science.gov (United States)

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

    2014-01-01

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

  11. 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.

  12. In situ analysis of ash deposits from black liquor combustion

    Energy Technology Data Exchange (ETDEWEB)

    Bernath, P. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Toronto, Ontario (Canada); Sinquefield, S.A. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Oregon State Univ., Eugene, OR (United States); Baxter, L.L.; Sclippa, G.; Rohlfing, C. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility; Barfield, M. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Arizona, Tucson, AZ (United States)

    1996-05-01

    Aerosols formed during combustion of black liquor cause a significant fire-side fouling problem in pulp mill recovery boilers. The ash deposits reduce heat transfer effectiveness, plug gas passages, and contribute to corrosion. Both vapors and condensation aerosols lead to the formation of such deposits. The high ash content of the fuel and the low dew point of the condensate salts lead to a high aerosol and vapor concentration in most boilers. In situ measurements of the chemical composition of these deposits is an important step in gaining a fundamental understanding of the deposition process. Infrared emission spectroscopy is used to characterize the composition of thin film deposits resulting from the combustion of black liquor and the deposition of submicron aerosols and vapors. New reference spectra of Na{sub 2}SO{sub 4}, K{sub 2}SO{sub 4}, Na{sub 2}CO{sub 3} and K{sub 2}CO{sub 3} pure component films were recorded and compared with the spectra of the black liquor deposit. All of the black liquor emission bands were identified using a combination of literature data and ab initio calculations. Ab initio calculations also predict the locations and intensities of bands for the alkali vapors of interest. 39 refs., 9 figs.

  13. Effect of grinding process on the level of leachability of the contaminants from the fly ashes from combustion of biomass

    Directory of Open Access Journals (Sweden)

    Pawluk Aleksandra

    2016-01-01

    Full Text Available The most commonly used renewable energy source in Polish energy production companies is solid biomass which is used both as a separate fuel or as a component co-incinerated together with (mostly hard coal. During its incineration the biomass generates by-products with diverse and variable physicochemical properties. The most of the waste from production of electricity and/or heat are fly ashes. The fly ashes from combustion of biomass are a particular kind of waste distinguished by high level of leaching of contaminants and variable chemical composition. The by-products from combustion can only be used in production when their physicochemical properties meet specific parameters. This article presents results of research on leachability of chemical pollutants from dry ashes of combustion or co-combustion of biomass. The study of the impact of grinding of ashes on the level of their leachability was also conducted. Ashes from combustion of biomass as well as their mixture with fluidized ash from combustion of charcoal were submitted to grinding process. Afterwards level of leachability was measured on them to determine prospect of utility in mining technologies.

  14. Mechanical Properties of Concrete Using Eggshell Ash and Rice Husk Ash As Partial Replacement Of Cement

    Directory of Open Access Journals (Sweden)

    Afizah Asman Nurul Shahadahtul

    2017-01-01

    Full Text Available This research was carried out to determine the optimum percentage of eggshell ash and rice husk ash (RHA as partial cement replacement. The samples were tested for its mechanical properties by using concrete grade G30 with cube mould (100 mm × 100 mm × 100 mm and prisms (100 mm × 100 mm × 500 mm. The samples were mixed with eggshell ash and RHA admixture with different proportions (2%:8%, 4%:6%, 6%:4%. Several types of test were conducted towards the samples, which are the slump test, compressive and flexural test. Based on previous researches, the strength of concrete reduced as replaced with eggshells. Most of the researches show the similar trend when partial cement is replaced using eggshell ash. Thus, to increase the strength, an admixture which has pozzolanic reactivity called rice husk ash (RHA is introduced into mix design which has been proved can help to improve the strength of concrete.

  15. International Database of Volcanic Ash Impacts

    Science.gov (United States)

    Wallace, K.; Cameron, C.; Wilson, T. M.; Jenkins, S.; Brown, S.; Leonard, G.; Deligne, N.; Stewart, C.

    2015-12-01

    Volcanic ash creates extensive impacts to people and property, yet we lack a global ash impacts catalog to organize, distribute, and archive this important information. Critical impact information is often stored in ephemeral news articles or other isolated resources, which cannot be queried or located easily. A global ash impacts database would improve 1) warning messages, 2) public and lifeline emergency preparation, and 3) eruption response and recovery. Ashfall can have varying consequences, such as disabling critical lifeline infrastructure (e.g. electrical generation and transmission, water supplies, telecommunications, aircraft and airports) or merely creating limited and expensive inconvenience to local communities. Impacts to the aviation sector can be a far-reaching global issue. The international volcanic ash impacts community formed a committee to develop a database to catalog the impacts of volcanic ash. We identify three user populations for this database: 1) research teams, who would use the database to assist in systematic collection, recording, and storage of ash impact data, and to prioritize impact assessment trips and lab experiments 2) volcanic risk assessment scientists who rely on impact data for assessments (especially vulnerability/fragility assessments); a complete dataset would have utility for global, regional, national and local scale risk assessments, and 3) citizen science volcanic hazard reporting. Publication of an international ash impacts database will encourage standardization and development of best practices for collecting and reporting impact information. Data entered will be highly categorized, searchable, and open source. Systematic cataloging of impact data will allow users to query the data and extract valuable information to aid in the development of improved emergency preparedness, response and recovery measures.

  16. Furnace construction having an ash pit with a radiation reflecting surface

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, W.H.

    1984-05-01

    A water-wall, coal-fired furnace has a Coutant transition section extending down from the lower end to the water wall to the surface of water impounded in the lower ash hopper. The surface of the water is provided with a reflecting material which will permit the passage of solid residue from the coal firing into the water while reflecting incident radiant heat back up into the generating section of the furnace.

  17. 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.

  18. 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.

  19. Ash melting behavior by Fourier transform infrared spectroscopy

    Institute of Scientific and Technical Information of China (English)

    LI Han-xu; QIU Xiao-sheng; TANG Yong-xin

    2008-01-01

    A Fourier Transform Infrared Spectroscopic (FTIR) method involving a Fe2O3 flux was used to learn how China's coal ash melts. The relationship between ash fusion temperature and chemical composition, as well as the effects of Fe2O3 flux on the ash fusion temperature were studied. The relationship between ash fusion temperature and chemical composition, mineralogical phases and functional groups was analyzed with the FTIR method. The results show that the ash fusion temperature is related to the location and transmittance of certain absorption peaks, which is of great significance for the study of ash behavior.

  20. Electrodialytic removal of Cd from biomass combustion fly ash

    DEFF Research Database (Denmark)

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

    2004-01-01

    Due to a high concentration of Cd, biomass combustion fly ash often fails to meet the Danish legislative requirements for recycling on agricultural fields. In this work the potential of using the method Electrodialytic Remediation to reduce the concentration of Cd in different biomass combustion...... fly ashes was studied. Four fly ashes were investigated, originating from combustion of straw (two ashes), wood chips, and co-firing of wood pellets and fuel oil, respectively. One of the straw ashes had been pre-washed and was obtained suspended in water, the other ashes were obtained naturally dry...

  1. 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.

  2. Photoinduced carrier annihilation in silicon pn junction

    Science.gov (United States)

    Sameshima, Toshiyuki; Motoki, Takayuki; Yasuda, Keisuke; Nakamura, Tomohiko; Hasumi, Masahiko; Mizuno, Toshihisa

    2015-08-01

    We report analysis of the photo-induced minority carrier effective lifetime (τeff) in a p+n junction formed on the top surfaces of a n-type silicon substrate by ion implantation of boron and phosphorus atoms at the top and bottom surfaces followed by activation by microwave heating. Bias voltages were applied to the p+ boron-doped surface with n+ phosphorus-doped surface kept at 0 V. The values of τeff were lower than 1 × 10-5 s under the reverse-bias condition. On the other hand, τeff markedly increased to 1.4 × 10-4 s as the forward-bias voltage increased to 0.7 V and then it leveled off when continuous-wave 635 nm light was illuminated at 0.74 mW/cm2 on the p+ surface. The carrier annihilation velocity S\\text{p + } at the p+ surface region was numerically estimated from the experimental τeff. S\\text{p + } ranged from 4000 to 7200 cm/s under the reverse-bias condition when the carrier annihilation velocity S\\text{n + } at the n+ surface region was assumed to be a constant value of 100 cm/s. S\\text{p + } markedly decreased to 265 cm/s as the forward-bias voltage increased to 0.7 V.

  3. LIQUIFIED NATURAL GAS (LNG CARRIERS

    Directory of Open Access Journals (Sweden)

    Daniel Posavec

    2010-12-01

    Full Text Available Modern liquefied natural gas carriers are double-bottom ships classified according to the type of LNG tank. The tanks are specially designed to store natural gas cooled to -161°C, the boiling point of methane. Since LNG is highly flammable, special care must be taken when designing and operating the ship. The development of LNG carriers has begun in the middle of the twentieth century. LNG carrier storage space has gradually grown to the current maximum of 260000 m3. There are more than 300 LNG carriers currently in operation (the paper is published in Croatian.

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

    Directory of Open Access Journals (Sweden)

    Justin G A Whitehill

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

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

    Science.gov (United States)

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

    2011-01-01

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

  6. 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.

  7. Estimating thermodynamic properties of coal, char, tar and ash

    Energy Technology Data Exchange (ETDEWEB)

    Eisermann, W.; Johnson, P. Conger, W.L.

    1980-01-01

    Methods of predicting the specific heat, enthalpy, and entropy of coal, char, tar and ash as a function of temperature and material composition are presented. The standard entropy of coal is approximated by comparing the behaviour of the standard entropies of a number of aliphatic and aromatic hydrocarbons as a function of the variables H/(C + N), O/(C + N), N/(C + N), and S/(C + N), where the variables are the atomic fractions of the respective elements. The standard entropy of a bituminous coal was found to be about 20 kJ/kmol carbon K and of the char to be about 10 kJ/kmol carbon K. Estimates of the enthalpy difference between 273 K and temperatures above 273 K deviated from published data by about 8.49% for chars and 8.55% for coals on the average. Maximum deviations of 18.3% and 17.6% respectively were found.

  8. National volcanic ash operations plan for aviation

    Science.gov (United States)

    ,; ,

    2007-01-01

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

  9. Characteristics of MSWI fly ash during vitrification

    Institute of Scientific and Technical Information of China (English)

    TIAN Shu-lei; WANG Qi; WANG Qun-hui; MA Hong-zhi

    2009-01-01

    The vitrification characteristics of municipal solid waste incinerator (MSWI) fly ash were investigated. Effects of temperature on the binding efficiency of heavy metals, the change of chemical compositions and the weight loss of fly ash in the range of 800 - 1350 ℃ were studied. Toxicity Characteristic Leaching Procedure (TCLP) of the United States was used to analyze the leaching characteristics of heavy metals in fly ash and molten slag. Results indicate that chemical compositions, the weight loss of fly ash and the binding efficiency of heavy metals in fly ash have a tremendous change in the range of 1150 - 1260 ℃. The percentage of CaO, SiO2and AI203 increases with the increasing temperature, whereas it is contrary for SO3 , K2O, Na20 and CI; especially when the temperature is 1260 ℃, the percentage of these four elements decreases sharply from 43.72%to 0. 71%. The weight loss occurs obviously in the range of 1150 - 1260 ℃. Heavy metals of Pb and Cd are almost vaporized above 1000 ℃. Cr is not volatile and its binding efficiency can reach 100% below 1000 ℃. Resuits of TCLP indicate that the heavy metal content of molten slag is beyond stipulated limit values.

  10. Graphene, a material for high temperature devices; intrinsic carrier density, carrier drift velocity, and lattice energy

    CERN Document Server

    Yin, Yan; Wang, Li; Jin, Kuijuan; Wang, Wenzhong

    2016-01-01

    Heat has always been a killing matter for traditional semiconductor machines. The underlining physical reason is that the intrinsic carrier density of a device made from a traditional semiconductor material increases very fast with a rising temperature. Once reaching a temperature, the density surpasses the chemical doping or gating effect, any p-n junction or transistor made from the semiconductor will fail to function. Here, we measure the intrinsic Fermi level (|E_F|=2.93k_B*T) or intrinsic carrier density (n_in=3.87*10^6 cm^-2 K^-2*T^2), carrier drift velocity, and G mode phonon energy of graphene devices and their temperature dependencies up to 2400 K. Our results show intrinsic carrier density of graphene is an order of magnitude less sensitive to temperature than those of Si or Ge, and reveal the great potentials of graphene as a material for high temperature devices. We also observe a linear decline of saturation drift velocity with increasing temperature, and identify the temperature coefficients of ...

  11. Macroscopic heat transport equations and heat waves in nonequilibrium states

    Science.gov (United States)

    Guo, Yangyu; Jou, David; Wang, Moran

    2017-03-01

    Heat transport may behave as wave propagation when the time scale of processes decreases to be comparable to or smaller than the relaxation time of heat carriers. In this work, a generalized heat transport equation including nonlinear, nonlocal and relaxation terms is proposed, which sums up the Cattaneo-Vernotte, dual-phase-lag and phonon hydrodynamic models as special cases. In the frame of this equation, the heat wave propagations are investigated systematically in nonequilibrium steady states, which were usually studied around equilibrium states. The phase (or front) speed of heat waves is obtained through a perturbation solution to the heat differential equation, and found to be intimately related to the nonlinear and nonlocal terms. Thus, potential heat wave experiments in nonequilibrium states are devised to measure the coefficients in the generalized equation, which may throw light on understanding the physical mechanisms and macroscopic modeling of nanoscale heat transport.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-03-15

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

  13. Correlation between the critical viscosity and ash fusion temperatures of coal gasifier ashes

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Peter Y. [National Energy Technology Lab. (NETL), Albany, OR (United States); Kwong, Kyei-Sing [National Energy Technology Lab. (NETL), Albany, OR (United States); Bennett, James [National Energy Technology Lab. (NETL), Albany, OR (United States)

    2015-09-27

    Coal gasification yields synthesis gas, an important intermediate in chemical manufacturing. It is also vital to the production of liquid fuels through the Fischer-Tropsch process and electricity in Integrated Gasification Combined Cycle power generation. Minerals naturally present in coal become molten in entrained-flow slagging gasifiers. Molten coal ash slag penetrates and dissolves refractory bricks, leading to costly plant shutdowns. The extent of coal ash slag penetration and refractory brick dissolution depends on the slag viscosity, the gasification temperature, and the composition of slag and bricks. Here, we measured the viscosity of several synthetic coal ash slags with a high-temperature rotary viscometer and their ash fusion temperatures through optical image analysis. We made all measurements in a carbon monoxide-carbon dioxide reducing atmosphere that approximates coal gasification conditions. Empirical correlation models based on ash fusion temperatures were used to calculate critical viscosity temperatures based on the coal ash compositions. These values were then compared with those obtained from thermodynamic phase-transition models. Finally, an understanding of slag viscosity as a function of ash composition is important to reducing refractory wear in slagging coal gasifiers, which would help to reduce the cost and environmental impact of coal for chemical and electricity production.

  14. Effects of Wood Ash on Soil Fungi

    DEFF Research Database (Denmark)

    Cruz Paredes, Carla

    in agricultural and forest soils focusing on soil microbial communities’ composition and function, particularly mycorrhizal fungi. Two study sites were used for this study, one in an agricultural field where different biomass ashes were evaluated as replacements for P fertilizers in barley, and a second one...... in a Norway spruce forest where different amounts of wood ash were spread on the soil to study the effects on ectomycorrhizal (ECM) fungi, bioaccumulation of metals in sporocarps, and microbial communities. Laboratory microcosm experiments were run in parallel to the field studies, to compare the effects...... effects on barley or associated AM fungi. Furthermore, wood ash can also be re-distributed to the forest without representing any risks for ECM fungal communities, N leaching, Cd bioaccumulation in sporocarps or the general activity of the soil microbial community....

  15. Laboratory study of volcanic ash electrification

    Science.gov (United States)

    Alois, Stefano; Merrison, Jonathan

    2016-04-01

    Electrostatic forces play an important role in the dynamics of volcanic plumes, for example in ash dispersion and aggregation phenomena. Field measurements of ash electrification are often technically challenging due to poor access and there lacks an accepted physical theory to describe the electrical charge exchange which occurs during particle contact. The goal of the study is to investigate single particle electrification under controlled conditions using advanced laboratory facilities. A novel technique is presented, based on the use of a laser based velocimeter. Here an electric field is applied and the field-induced drift velocity of (micron-sized) ash grains is measured as well as the particles fall velocity. This allows the simultaneous determination of a suspended grains size and electrical charge. The experiments are performed in a unique environmental wind tunnel facility under controlled low-pressure conditions. Preliminary results of particle electrification will be presented.

  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. Eco-friendly fly ash utilization: potential for land application

    Energy Technology Data Exchange (ETDEWEB)

    Malik, A.; Thapliyal, A. [Indian Institute of Technology Delhi, New Delhi (India)

    2009-07-01

    The increase in demand for power in domestic, agricultural, and industrial sectors has increased the pressure on coal combustion and aggravated the problem of fly ash generation/disposal. Consequently the research targeting effective utilization of fly ash has also gained momentum. Fly ash has proved to be an economical substitute for expensive adsorbents as well as a suitable raw material for brick manufacturing, zeolite synthesis, etc. Fly ash is a reservoir of essential minerals but is deficient in nitrogen and phosphorus. By amending fly ash with soil and/or various organic materials (sewage sludge, bioprocess materials) as well as microbial inoculants like mycorrhizae, enhanced plant growth can be realized. Based on the sound results of large scale studies, fly ash utilization has grown into prominent discipline supported by various internationally renowned organizations. This paper reviews attempts directed toward various utilization of fly ash, with an emphasis on land application of organic/microbial inoculants amended fly ash.

  18. Growth of Larval Agrilus planipennis (Coleoptera: Buprestidae) and Fitness of Tetrastichus planipennisi (Hymenoptera: Eulophidae) in Blue Ash (Fraxinus quadrangulata) and Green Ash (F. pennsylvanica).

    Science.gov (United States)

    Peterson, Donnie L; Duan, Jian J; Yaninek, J S; Ginzel, Matthew D; Sadof, Clifford S

    2015-12-01

    Emerald ash borer (Agrilus planipennis Fairmaire) is an invasive primary pest of North American ash (Fraxinus spp.) trees. Blue ash (F. quadrangulata) is less susceptible to emerald ash borer infestations in the forest than other species of North American ash. Whereas other studies have examined adult host preferences, we compared the capacity of emerald ash borer larvae reared from emerald ash borer eggs in the field and in the laboratory to survive and grow in blue ash and the more susceptible green ash (F. pennsylvanica). Emerald ash borer larval survivorship was the same on both ash species. Mortality due to wound periderm formation was only observed in living field grown trees, but was low (<4%) in both green and blue ash. No difference in larval mortality in the absence of natural enemies suggests that both green and blue ash can support the development of emerald ash borer. Larvae reared from eggs on blue ash were smaller than on green ash growing in the field and also in bolts that were infested under laboratory conditions. In a laboratory study, parasitism rates of confined Tetrastichus planipennisi were similar on emerald ash borer larvae reared in blue and green ash bolts, as were fitness measures of the parasitoid including brood size, sex ratio, and adult female size. Thus, we postulate that emerald ash borer larvae infesting blue ash could support populations of T. planipennisi and serve as a potential reservoir for this introduced natural enemy after most of the other native ash trees have been killed.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-08-01

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

  20. Synthesis of magnesium silicate from wheat husk ash: Effects of parameters on structural and surface properties

    Directory of Open Access Journals (Sweden)

    Pinar Terzioglu

    2012-11-01

    Full Text Available In the present study, magnesium silicate was produced by using wheat husk ash. Wheat husk was burned at 600 °C to obtain an amorphous ash structure, and the ash was processed with sodium hydroxide solution with heat to extract silica. Sodium silicate solution and magnesium salts were used to synthesize magnesium silicate. The present study investigates effects of the feeding rate on magnesium silicate production (0.6 mL/min, 35 mL/min, 70 mL/min, the type of magnesium salt (MgSO4 • 7H2O or MgCl2 • 6H2O, temperature (25 °C or 50 °C, and the washing agent (water and acetone on the chemical composition and surface characteristics of magnesium silicate. The results demonstrated that all of the variables affected the surface characteristics of magnesium silicate, such as surface area, particle size, and pore volume. However, it was also observed that the studied parameters did not affect the chemical composition of magnesium silicate. The wheat husk ash-based magnesium silicates obtained in the experimental study had a BET surface area ranging from 79 to 91 m2/g and a particle size varying from 42 to 63 µm.

  1. Initial fate of fine ash and sulfur from large volcanic eruptions

    Directory of Open Access Journals (Sweden)

    U. Niemeier

    2009-08-01

    Full Text Available Large volcanic eruptions emit huge amounts of sulfur and fine ash into the stratosphere. These products cause an impact on radiative processes, temperature and wind patterns. In simulations with a General Circulation Model including detailed aerosol microphysics, the relation between the impact of sulfur and fine ash is determined for different eruption strengths and locations, one in the tropics and one in high Northern latitudes. Fine ash with effective radii between 1 μm and 15 μm has a lifetime of several days only. Nevertheless, the strong absorption of shortwave and longwave radiation causes additional heating and cooling of ±20 K/day and impacts the evolution of the volcanic cloud. Depending on the location of the volcanic eruption, transport direction changes due to the presence of fine ash, vortices develop and temperature anomalies at ground increase. The results show substantial impact on the local scale but only minor impact on the evolution of sulfate in the stratosphere in the month after the simulated eruptions.

  2. Initial fate of fine ash and sulfur from large volcanic eruptions

    Directory of Open Access Journals (Sweden)

    S. Self

    2009-11-01

    Full Text Available Large volcanic eruptions emit huge amounts of sulfur and fine ash into the stratosphere. These products cause an impact on radiative processes, temperature and wind patterns. In simulations with a General Circulation Model including detailed aerosol microphysics, the relation between the impact of sulfur and fine ash is determined for different eruption strengths and locations, one in the tropics and one in high Northern latitudes. Fine ash with effective radii between 1 μm and 15 μm has a lifetime of several days only. Nevertheless, the strong absorption of shortwave and long-wave radiation causes additional heating and cooling of ±20 K/day and impacts the evolution of the volcanic cloud. Depending on the location of the volcanic eruption, transport direction changes due to the presence of fine ash, vortices develop and temperature anomalies at ground increase. The results show substantial impact on the local scale but only minor impact on the evolution of sulfate in the stratosphere in the month after the simulated eruptions.

  3. Thermal treatment and utilization of Al-rich waste in high calcium fly ash geopolymeric materials

    Science.gov (United States)

    Chindaprasirt, Prinya; Rattanasak, Ubolluk; Vongvoradit, Pimdao; Jenjirapanya, Supichart

    2012-09-01

    The Al-rich waste with aluminium and hydrocarbon as the major contaminant is generated at the wastewater treatment unit of a polymer processing plant. In this research, the heat treatment of this Al-rich waste and its use to adjust the silica/alumina ratio of the high calcium fly ash geopolymer were studied. To recycle the raw Al-rich waste, the waste was dried at 110°C and calcined at 400 to 1000°C. Mineralogical analyses were conducted using X-ray diffraction (XRD) to study the phase change. The increase in calcination temperature to 600, 800, and 1000°C resulted in the phase transformation. The more active alumina phase of active γ-Al2O3 was obtained with the increase in calcination temperature. The calcined Al-rich waste was then used as an additive to the fly ash geopolymer by mixing with high calcium fly ash, water glass, 10 M sodium hydroxide (NaOH), and sand. Test results indicated that the calcined Al-rich waste could be used as an aluminium source to adjust the silica/alumina ratio and the strength of geopolymeric materials. The fly ash geopolymer mortar with 2.5wt% of the Al-rich waste calcined at 1000°C possessed the 7-d compressive strength of 34.2 MPa.

  4. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment

    Energy Technology Data Exchange (ETDEWEB)

    Visa, Maria, E-mail: maria.visa@unitbv.ro; Chelaru, Andreea-Maria, E-mail: andreea.chelaru1@yahoo.com

    2014-06-01

    Fly ash resulted from coal burning is a waste that can be used in wastewater treatment for removal of dyes and heavy metals by adsorption. Class “F” fly ash (FA), collected from the Central Heat and Power (CHP) Plant Brasov (Romania), with oxides composition SiO{sub 2}/Al{sub 2}O{sub 3} over 2.4 was used for obtaining a new substrate with good adsorption capacity for dyes and heavy metals from wastewater. A new material was obtained from modified fly ash with NaOH and hexadecyltrimethylammonium bromide (HTAB) a cationic surfactant. Contact time, optimum amount of substrate and the pH corresponding to 50 mL solution of pollutants were the parameters optimized for obtaining the maximum efficiency in the adsorption process. The optimized adsorption parameters were further used in thermodynamic and kinetic studies of the adsorption processes. The adsorption kinetic mechanisms, and the substrate capacities are further discussed correlated with the surface structure (XRD), composition (EDS, FTIR), and morphology (SEM, AFM). The results indicate that the novel nano-substrate composite with fly ash modified can be used as an efficient and low cost adsorbent for simultaneous removal of dyes and heavy metals, the resulted water respects the discharge regulations.

  5. Cleaner phosphogypsum, coal combustion ashes and waste incineration ashes for application in building materials: A review

    Energy Technology Data Exchange (ETDEWEB)

    L. Reijnders [University of Amsterdam, Amsterdam (Netherlands)

    2007-02-15

    Application of phosphogypsum, coal combustion ashes and waste incineration ashes in building materials has been limited by the presence of minor components that are hazardous, such as radioactive substances, chlorinated dioxins and heavy metals, or have a negative impact on product quality or production economics, such as phosphate, fluoride, carbon and chloride. Source reduction, destruction of persistent organics and separation techniques may reduce the concentrations of such components. With a few exceptions, separation techniques currently lead to significantly higher (private) costs. Higher waste disposal costs, tighter regulations and higher prices for competing virgin minerals could make the use of the purified phosphogypsum and ashes in building materials more attractive.

  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. Changeing of fly ash leachability after grinding

    Science.gov (United States)

    Lakatos, J.; Szabo, R.; Racz, A.; Banhidi, O.; Mucsi, G.

    2016-04-01

    Effect of grinding on the reactivity of fly ash used for geopolymer production was tested. Extraction technique using different alkaline and acidic solutions were used for detect the change of the solubility of elements due to the physical and mechano-chemical transformation of minerals in function of grinding time. Both the extraction with alkaline and acidic solution have detected improvement in solubility in function of grinding time. The enhancement in alkaline solution was approx. 100% in case of Si and Al. The acidic medium able to dissolve the fly ash higher manner than the alkaline, therefore the effect of grinding was found less pronounced.

  8. Physical cleaning of high carbon fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Gray, McMahan L.; Champagne, Kenneth J.; Soong, Yee; Killmeyer, Richard P. [National Energy Technology Laboratory, US Department of Energy, P.O. Box 10940, Cochran Mills Roads, 15236 Pittsburgh, PA (United States); Maroto-Valer, M. Mercedes; Andresen, John M. [The Energy Institute, The Pennsylvania State University, 405 Academic Activities Building, 16802-2308 University Park, PA (United States); Ciocco, Michael V.; Zandhuis, Paul H. [Parson Project Services Inc, National Energy Technology Laboratory, P.O. Box 618, 15129 Library, Pittsburgh, PA (United States)

    2002-04-20

    An industrial fly ash sample was cleaned by three different processes, which were triboelectrostatic separation, ultrasonic column agglomeration, and column flotation. The unburned carbon concentrates were collected at purities ranging up to 62% at recoveries of 62%. In addition, optical microscopy studies were conducted on the final carbon concentrates to determine the carbon forms (inertinite, isotropic coke and anisotropic coke) collected from these various physical-cleaning processes. The effects of the various cleaning processes on the production of different carbon forms from high carbon fly ashes will be discussed.

  9. Preparation of heteropolyacid/TiO{sub 2}/fly-ash-cenosphere photocatalyst for the degradation of ciprofloxacin from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Wu Di; Huo Pengwei; Lu Ziyang; Gao Xun [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China); Liu Xiaolin [School of Biology and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212013 (China); Shi Weidong [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China); Yan Yongsheng, E-mail: huopw@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013 (China)

    2012-07-01

    The TiO{sub 2}/fly-ash cenosphere photocatalysts modified with heteropolyacid were synthesized by sol-gel followed solvothermal method at 40 Degree-Sign C. Their chemical composition and optical absorption were characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (UV-vis DRS), Fourier Transform Infra Red spectroscopy (FTIR) and Scanning electron microscopy (SEM). It was found that heteropolyacid modification could facilitate the absorption edge of TiO{sub 2}/fly-ash cenosphere photocatalyst to shift the visible light region. Heteropolyoxanion could be loaded on the titanium dioxide surface, by which could hinder the recombination rate of excited electron holes. The photocatalytic activity of TiO{sub 2}/fly-ash cenospheres modified with heteropolyacid was observed for the degradation of ciprofloxacin (CPFX) under visible light irradiation. The result from degradation of CPFX suggested that the photocatalytic activity of TiO{sub 2}/fly-ash cenospheres modified with silicotungstic acid was superior. The synergistic effects of heteropolyacid in modified TiO{sub 2}/fly-ash cenospheres photocatalyst particles were responsible for improving visible light photocatalytic activity. Besides, the novel photocatalyst was easy to recycle during post treatment because the fly-ash cenosphere was adopted for carrier.

  10. Thermal Stability of Volcanic Ash versus Turbine Ingestion Test Sands: an Experimental Investigation

    Science.gov (United States)

    Cimarelli, C.; Kueppers, U.; Hess, K.; Dingwell, D. B.; Rickerby, D. S.; Madden, P. C.

    2010-12-01

    Volcanic eruptions are an inevitable natural threat. The range of eruptive styles is large and short term fluctuations of explosivity or vent position pose a large risk not necessarily confined to the immediate vicinity of a volcano. Explosive eruptions rather may also affect aviation, infrastructure and climate, regionally as well as globally. The recent eruption of Eyjafjallajökull drastically brought into common awareness how volcanic activity can affect every day’s life and disrupt air traffic. The presence of solid particles in the air ingested in jet turbines may cause harm as it 1) may deposit on surfaces upon being heated up and 2) abrade upon impact. Particles suspended in the atmosphere may have different origins, including volcanic ash, aeolian sand, or incineration residues, each of them having different chemical and physical characteristics. To date, aircraft turbine operability has been investigated - amongst other tests - through the ingestion of sands whose grains have different mineralogical nature. Due to high cooling rates, volcanic ash is usually made up of glass, i.e. an amorphous phase lacking crystallographic order. Glass and crystal behave very differently to heating up. Glass will soften - and accordingly change shape or stick to surfaces - at temperatures as low as 700 °C, depending on the chemical composition. Crystals however need higher melting temperatures; quartz for example has a melting point at around 1700 °C. Accordingly, the effect of ash on the operational reliability of aircraft turbines may not be judged solely based on knowledge commonly derived from mineral sand ingestion testing. In order to investigate the behaviour upon heating, we performed a series of experiments at ten temperature steps between 700 and 1600 °C. We used three different samples: 1) Ash from the explosive phase of Eyjafjallajökull; 2) MIL E-5007C test sand (MTS), and 3) Arizona Test Dust (ATD). MTS and ATD are commonly used for aircraft turbine

  11. Ash Deposition Trials at Three Power Stations in Denmark

    DEFF Research Database (Denmark)

    Laursen, Karin; Frandsen, Flemming; Larsen, Ole Hede

    1998-01-01

    the probe temperature did influence the composition of deposits for coals with medium ash deposition propensities. These results may indicate that coals with medium to high ash deposition propensities in existing boilers may cause increasing ash deposit formation in future boilers with higher steam...

  12. 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

  13. Oil ash corrosion; A review of utility boiler experience

    Energy Technology Data Exchange (ETDEWEB)

    Paul, L.D. (Babcock and Wilcox Co., Alliance, OH (United States)); Seeley, R.R. (Babcock and Wilcox Canada Ltd., Cambridge, ON (Canada))

    1991-02-01

    In this paper a review of experience with oil ash corrosion is presented along with current design practices used to avoid excessive tube wastage. Factors influencing oil ash corrosion include fuel chemistry, boiler operation, and boiler design. These factors are interdependent and determine the corrosion behavior in utility boilers. Oil ash corrosion occurs when vanadium-containing ash deposits on boiler tube surfaces become molten. These molten ash deposits dissolve protective oxides and scales causing accelerated tube wastage. Vanadium is the major fuel constituent responsible for oil ash corrosion. Vanadium reacts with sodium, sulfur, and chlorine during combustion to produce lower melting temperature ash compositions, which accelerate tube wastage. Limiting tube metal temperatures will prevent ash deposits from becoming molten, thereby avoiding the onset of oil ash corrosion. Tube metal temperatures are limited by the use of a parallel stream flow and by limiting steam outlet temperatures. Operating a boiler with low excess air has helped avoid oil ash corrosion by altering the corrosive combustion products. Air mixing and distribution are essential to the success of this palliative action. High chromium alloys and coatings form more stable protective scaled on tubing surfaces, which result in lower oil ash corrosion rates. However, there is not material totally resistant to oil ash corrosion.

  14. The Rheology of Vegetative Ash-laden Debris Flows

    Science.gov (United States)

    Burns, K. A.; Gabet, E.

    2006-12-01

    There is mounting observational evidence that vegetative ash created in a forest fire may play a major role in reducing infiltration and leads to the generation of debris flows on these burned hillslopes. A viscometer was used to measure the viscosity of ash slurries of varying concentrations, as well as slurries containing both fine- grained clastic sediment (sand and silt sized) and vegetative ash at varying concentrations. Initial results from these experiments indicate that increasing the concentration of ash increases effective viscosity of the slurry. Increasing the ash concentration by 5% increases the effective viscosity of the slurry by 10-50% over a range of shear rates. Also, ash-only slurries appear to shear thin with increasing shear rate at all concentrations. For example, with a 60% ash concentration, increasing the shear rate from 5/s to 40/s reduces the effective viscosity by 90%. For the mixed ash and fine-grained sediment slurries, increasing the percentage of ash relative to the percentage of clastic sediment dramatically increases the viscosity of the slurry even though the ash and finest-grained sediment are approximately the same size. A 50% concentration slurry containing only silt-sized clastic particles has a 40-70% lower effective viscosity than a slurry of the same concentration containing only ash particles. Therefore, the ash particles behave differently than clastic sediment particles.

  15. 77 FR 55895 - Permanent Closure of Cincinnati Blue Ash Airport

    Science.gov (United States)

    2012-09-11

    ... Federal Aviation Administration Permanent Closure of Cincinnati Blue Ash Airport AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of permanent closure of Cincinnati Blue Ash Airport (ISZ). SUMMARY: The... Cincinnati advising that on August 29, 2012, it was permanently closing Cincinnati Blue Ash Airport...

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

    Science.gov (United States)

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

    2012-02-01

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

  17. Observation of Eyjafjallajökull volcano ash over Poland

    Science.gov (United States)

    Zielinski, T.; Petelski, T.; Makuch, P.; Kowalczyk, J.; Rozwadowska, A.; Drozdowska, V.; Markowicz, K.; Malinowski, S.; Kardas, A.; Posyniak, M.; Jagodnicka, A. K.; Stacewicz, T.; Piskozub, J.

    2010-05-01

    The plume of Eyjafjallajökull volcano ash has been identified over Poland using three instruments (two lidars and a ceilometer) stationed in two locations: Sopot in northern Poland and Warsaw in central-eastern Poland. The observations made it possible to establish the base of the ash layer. However ash concentration could not be determined.

  18. 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.

  19. Emerald ash borer biological control release and recovery guidelines

    Science.gov (United States)

    Juli S. Gould; Leah S. Bauer; Jian. Duan

    2015-01-01

    Emerald ash borer (EAB), a beetle from Asia that feeds on ash trees, was discovered as the cause of extensive ash mortality in southeast Michigan and adjacent areas of Canada in 2002. It is thought that this destructive pest was introduced in the early 1990's in infested solid wood packing material originating in Asia. Shortly after EAB was discovered in North...

  20. Product policies. characterization results ash by burning layer fluid

    OpenAIRE

    Neamtu, Ion; Achim, Marian Lucian

    2009-01-01

    By economical and at the same time ecological reasons, industrial refuses (ashes) are being transported in waste dumps like offal’s .To reduce the storage surfaces these offal’s are incinerated and results a new refuse - the ash.(Ex. paper factories, thermo power stations).It's very important to find solutions to turn to good account the ash.

  1. 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.

  2. 42 CFR 421.200 - Carrier functions.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Carrier functions. 421.200 Section 421.200 Public...) MEDICARE PROGRAM MEDICARE CONTRACTING Carriers § 421.200 Carrier functions. A contract between CMS and a carrier specifies the functions to be performed by the carrier. The contract may include any or all of...

  3. 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

  4. Effect of ash circulation in gasification melting system on concentration and leachability of lead in melting furnace fly ash.

    Science.gov (United States)

    Okada, Takashi; Suzuki, Masaru

    2013-11-30

    In some gasification-melting plants, generated melting furnace fly ash is returned back to the melting furnace for converting the ash to slag. This study investigated the effect of such ash circulation in the gasification-melting system on the concentration and leachability of lead in the melting furnace fly ash. The ash circulation in the melting process was simulated by a thermodynamic calculation, and an elemental analysis and leaching tests were performed on a melting furnace fly ash sample collected from the gasification-melting plant with the ash circulation. It was found that by the ash circulation in the gasification-melting, lead was highly concentrated in the melting furnace fly ash to the level equal to the fly ash from the ash-melting process. The thermodynamic calculation predicted that the lead volatilization by the chlorination is promoted by the ash circulation resulting in the high lead concentration. In addition, the lead extraction from the melting furnace fly ash into a NaOH solution was also enhanced by the ash circulation, and over 90% of lead in the fly ash was extracted in 5 min when using 0.5 mol l(-1) NaOH solution with L/S ratio of 10 at 100 °C. Based on the results, a combination of the gasification-melting with the ash circulation and the NaOH leaching method is proposed for the high efficient lead recovery. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Root secretion stimulating ash growth in larch-ash mixed forest

    Institute of Scientific and Technical Information of China (English)

    吴俊民; 刘广平; 王晓水; 吴保国

    2000-01-01

    Allelopathic effect of larch (Larix gmelini ) on the ash growth (Fraximus mandshurica) was studied in artificial cultivation tests. The results revealed that the larch root secretion obviously stimulated the ash growth. In order to determine the main stimulation allelochemicals, the chemical composition was analyzed. By contrasting the contents of carbohydrate and aminoacid in root secretion of larch and ash, it was concluded that the carbohydrate and aminoacid were not important stimulation allelochemicals. The organic acid and other components in root secretion of larch and ash were analyzed by GC and GC-MS analysis. The sand culture tests were carried out with selected model compounds. The results showed that benzeneacetic acid, benzenepropionic acid and phenolic acids in root secretion of larch were the main stimulation allelochemicals.

  6. Mössbauer characterization of feed coal, ash and fly ash from a thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Reyes Caballero, F.; Martínez Ovalle, S. A., E-mail: s.agustin.martinez@uptc.edu.co; Moreno Gutiérrez, M. [Universidad Pedagógica y Tecnológica de Colombia, UPTC, Grupo de Física Nuclear Aplicada y Simulación (Colombia)

    2015-06-15

    The aim of this work was apply {sup 57}Fe Transmission Mössbauer Spectroscopy at room temperature in order to study the occurrence of iron-containing mineral phases in: 1) feed coal; 2) coal ash, obtained in different stages of the ASTM D3174 standard method; and 3) fly ash, produced when coal is burned in the TERMOPAIPA IV thermal power plant localized in Boyacá, Colombia. According to obtained results, we can conclude the occurrence of pyrite and jarosite in the feed coal; Fe{sup 2+} and Fe{sup 3+} crystalline paramagnetic phases, superparamagnetic hematite and hematite in coal ash; Fe{sup 2+} and Fe{sup 3+} noncrystalline and crystalline phases, magnetite and hematite in fly ash. Precisely, for a basic understanding, this work discusses some the possible transformations that take place during coal combustion.

  7. Source water contributions and hydrologic responses to simulated emerald ash borer infestations in depressional black ash wetlands

    Science.gov (United States)

    Matthew J. Van Grinsven; Joseph P. Shannon; Joshua C. Davis; Nicholas W. Bolton; Joseph W. Wagenbrenner; Randall K. Kolka; Thomas Grant Pypker

    2017-01-01

    Forested wetlands dominated by black ash (Fraxinus nigra) are currently threatened by the rapid expansion of the exotic emerald ash borer (EAB) (Agrilus planipennis, Coleoptera: Buprestidae) in North America, and very little is known about the hydrology and ecology of black ash wetlands. The ecohydrological response of...

  8. Application of polymeric flocculant for enhancing settling of the pond ash particles and water drainage from hydraulically stowed pond ash

    Institute of Scientific and Technical Information of China (English)

    Mishra Devi Prasad; Das Samir Kumar

    2013-01-01

    Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash.In this study the effect of polymeric flocculant on settling of the ash particles and drainage of water during pond ash stowing are investigated.In addition,the parameters,viz.drainage and absorption of water during pond ash stowing are quantified by stowing a mine goaf model with pond ash slurries of five different concentrations added with and without flocculant.The study revealed that addition of only 5 × 10-6 of Sodium Carboxymethyl Cellulose (Na-CMC)flocculant with the pond ash slurries during stowing offers best result in terms of quicker settling of the ash particles and enhanced water drainage from the hydraulically stowed pond ash.Besides,it resulted in drainage of more than 85% of the total water used in the initial 45 min of stowing.The improvement in drainage is caused due to coagulation and flocculation of the pond ash particles because of charge neutralization and particle-particle bridging.This study may provide a basis for estimating the drainage and absorption of water during the real pond ash stowing operation in underground mines.

  9. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

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

    2016-01-01

    deposits were prepared on superheater tubes and sintered in an oven at temperatures up to 1000 °C. Subsequently, the deposits were sheared off by an electrically controlled arm, and the corresponding adhesion strength was measured. The results reveal the effect of temperature, ash/deposit composition......, sintering duration, and steel type on the adhesion strength....

  10. Lixiviation of fly ash. Uitloging van vliegas

    Energy Technology Data Exchange (ETDEWEB)

    Verhagen, L.

    1988-01-01

    The lixiviation of a number of elements (Na, K, Ca, Mg, V, As, Sb and Hg) from different fly ash products (fired and cement bounded products) is investigated. A theoretical description of diffusion from a fly ash product is given as well as a standard test to determine the lixiviation rate. Lixiviation can be interpreted as a diffusion process. Diffusion of an element X from a fly ash product can be described with the following parameters: the effective diffusion coefficient, the fraction that is available for lixiviation and the tortuosity of the product. The physical meaning of the determined tortuosity is not clear. The behavior of tracers in the product is compared with the behavior of the corresponding element. Often this behavior deviates, sometimes even considerably. From a comparison of fly ash products it appears that cement bounded products are better able to combine with arsenicum and antimony than fired products. None of the investigated products caused concentrations of micro-elements way above the stated norm. Improvement as for lixiviation behavior of the products seems to be possible, in particular for bricks. 8 refs., 17 tabs., 26 figs.

  11. Phosphorus recovery from sewage sludge char ash

    NARCIS (Netherlands)

    Atienza-Martinez, M.; Gea, G.; Arauzo, J.; Kersten, S.R.A.; Kootstra, A.M.J.

    2014-01-01

    Phosphorus was recovered from the ash obtained after combustion at different temperatures (600 °C, 750 °C and 900 °C) and after gasification (at 820 °C using a mixture of air and steam as fluidising agent) of char from sewage sludge fast pyrolysis carried out at 530 °C. Depending on the leaching con

  12. Climate change and the ash dieback crisis

    Science.gov (United States)

    Goberville, Eric; Hautekèete, Nina-Coralie; Kirby, Richard R.; Piquot, Yves; Luczak, Christophe; Beaugrand, Grégory

    2016-01-01

    Beyond the direct influence of climate change on species distribution and phenology, indirect effects may also arise from perturbations in species interactions. Infectious diseases are strong biotic forces that can precipitate population declines and lead to biodiversity loss. It has been shown in forest ecosystems worldwide that at least 10% of trees are vulnerable to extinction and pathogens are increasingly implicated. In Europe, the emerging ash dieback disease caused by the fungus Hymenoscyphus fraxineus, commonly called Chalara fraxinea, is causing a severe mortality of common ash trees (Fraxinus excelsior); this is raising concerns for the persistence of this widespread tree, which is both a key component of forest ecosystems and economically important for timber production. Here, we show how the pathogen and climate change may interact to affect the future spatial distribution of the common ash. Using two presence-only models, seven General Circulation Models and four emission scenarios, we show that climate change, by affecting the host and the pathogen separately, may uncouple their spatial distribution to create a mismatch in species interaction and so a lowering of disease transmission. Consequently, as climate change expands the ranges of both species polewards it may alleviate the ash dieback crisis in southern and occidental regions at the same time. PMID:27739483

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

    African Journals Online (AJOL)

    Preferred Customer

    Also, fly ash has been found to be an efficient adsorbent for water treatment in the removal of ... properties for the removal of metal ions and organics; the residual sludge produced is used in ... investigate the reuse of the adsorbent for better economy of the process. ..... Ogbomoso, Oyo State, Nigeria to complete this article.

  14. Heavy metals in MSW incineration fly ashes

    DEFF Research Database (Denmark)

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

    2003-01-01

    Incineration is a common solution for dealing with the increasing amount of municipal solid waste (MSW). During the process, the heavy metals initially present in the waste go through several transformations, ending up in combustion products, such as fly ash. This article deals with some issues r...

  15. Characterizing uncertainty in the motion, future location and ash concentrations of volcanic plumes and ash clouds

    Science.gov (United States)

    Webley, P.; Patra, A. K.; Bursik, M. I.; Pitman, E. B.; Dehn, J.; Singh, T.; Singla, P.; Stefanescu, E. R.; Madankan, R.; Pouget, S.; Jones, M.; Morton, D.; Pavolonis, M. J.

    2013-12-01

    Forecasting the location and airborne concentrations of volcanic ash plumes and their dispersing clouds is complex and knowledge of the uncertainty in these forecasts is critical to assess and mitigate the hazards that could exist. We show the results from an interdisciplinary project that brings together scientists drawn from the atmospheric sciences, computer science, engineering, mathematics, and geology. The project provides a novel integration of computational and statistical modeling with a widely-used volcanic particle dispersion code, to provide quantitative measures of confidence in predictions of the motion of ash clouds caused by volcanic eruptions. We combine high performance computing and stochastic analysis, resulting in real time predictions of ash cloud motion that account for varying wind conditions and a range of model variables. We show how coupling a real-time model for ash dispersal, PUFF, with a volcanic eruption model, BENT, allows for the definition of the variability in the dispersal model inputs and hence classify the uncertainty that can then propagate for the ash cloud location and downwind concentrations. We additionally analyze the uncertainty in the numerical weather prediction forecast data used by the dispersal model by using ensemble forecasts and assess how this affects the downwind concentrations. These are all coupled together and by combining polynomical chaos quadrature with stochastic integration techniques, we provide a quantitative measure of the reliability (i.e. error) of those predictions. We show comparisons of the downwind height calculations and mass loadings with observations of ash clouds available from satellite remote sensing data. The aim is to provide a probabilistic forecast of location and ash concentration that can be generated in real-time and used by those end users in the operational ash cloud hazard assessment environment.

  16. Distinguishing defensive characteristics in the phloem of ash species resistant and susceptible to emerald ash borer.

    Science.gov (United States)

    Cipollini, Don; Wang, Qin; Whitehill, Justin G A; Powell, Jeff R; Bonello, Pierluigi; Herms, Daniel A

    2011-05-01

    We examined the extent to which three Fraxinus cultivars and a wild population that vary in their resistance to Emerald Ash Borer (EAB) could be differentiated on the basis of a suite of constitutive chemical defense traits in phloem extracts. The EAB-resistant Manchurian ash (F. mandshurica, cv. Mancana) was characterized by having a rapid rate of wound browning, a high soluble protein concentration, low trypsin inhibitor activities, and intermediate levels of peroxidase activity and total soluble phenolic concentration. The EAB-susceptible white ash (F. americana, cv. Autumn Purple) was characterized by a slow wound browning rate and low levels of peroxidase activity and total soluble phenolic concentrations. An EAB-susceptible green ash cultivar (F. pennsylvanica, cv. Patmore) and a wild accession were similar to each other on the basis of several chemical defense traits, and were characterized by high activities of peroxidase and trypsin inhibitor, a high total soluble phenolic concentration, and an intermediate rate of wound browning. Lignin concentration and polyphenol oxidase activities did not differentiate resistant and susceptible species. Of 33 phenolic compounds separated by HPLC and meeting a minimum criterion for analysis, nine were unique to Manchurian ash, five were shared among all species, and four were found in North American ashes and not in the Manchurian ash. Principal components analysis revealed clear separations between Manchurian, white, and green ashes on the basis of all phenolics, as well as clear separations on the basis of quantities of phenolics that all species shared. Variation in some of these constitutive chemical defense traits may contribute to variation in resistance to EAB in these species.

  17. 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.

  18. Basic Stand Alone Carrier Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...

  19. Ash3d: A finite-volume, conservative numerical model for ash transport and tephra deposition

    Science.gov (United States)

    Schwaiger, Hans F.; Denlinger, Roger P.; Mastin, Larry G.

    2012-01-01

    We develop a transient, 3-D Eulerian model (Ash3d) to predict airborne volcanic ash concentration and tephra deposition during volcanic eruptions. This model simulates downwind advection, turbulent diffusion, and settling of ash injected into the atmosphere by a volcanic eruption column. Ash advection is calculated using time-varying pre-existing wind data and a robust, high-order, finite-volume method. Our routine is mass-conservative and uses the coordinate system of the wind data, either a Cartesian system local to the volcano or a global spherical system for the Earth. Volcanic ash is specified with an arbitrary number of grain sizes, which affects the fall velocity, distribution and duration of transport. Above the source volcano, the vertical mass distribution with elevation is calculated using a Suzuki distribution for a given plume height, eruptive volume, and eruption duration. Multiple eruptions separated in time may be included in a single simulation. We test the model using analytical solutions for transport. Comparisons of the predicted and observed ash distributions for the 18 August 1992 eruption of Mt. Spurr in Alaska demonstrate to the efficacy and efficiency of the routine.

  20. Ash fusion temperatures and their association with the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.K.; Wall, T.F.; Gupta, R.P. [Cooperative Research Centre for Black Coal Utilisation, Newcastle, NSW (Australia); Creelman, R.A. [Creelman (R.A.) and Associates, Sydney, NSW (Australia)

    1997-04-01

    Ash deposition on furnace walls in PF (pulverized fuel) furnaces is called slagging when it occurs in the high temperature areas of furnaces directly exposed to flame radiation and fouling in other regions such as tubes in the convection section of the boiler. There are well documented shortcomings of certain approaches relating to their uncertainties as predictive tools for plant performance such as poor repeatability and re-producibility of ash fusion measurements. The nature of physical and chemical changes occurring during melting of coal ash has been investigated in the current study to provide an alternative procedure to the ash fusion test. Shrinkage measurements are frequently used in metallurgy and ceramic science to study the physical properties of materials at high temperatures. The output of this experiment provides three to four `peaks` (maximum rate of shrinkage with temperature) of different intensity and at different temperatures which are related to melting characteristics of the sample. It was concluded that shrinkage extents exceeding 50 percent indicated that the effect of the ash particle size is of secondary importance compared to ash chemistry in determining shrinkage levels, with fine particles giving rapid shrinkage events 10 degrees C lower in temperature. (author). 7 figs., refs.

  1. Hydrothermal and mechanochemical reactions of rice husk ash with calcium hydroxide

    Energy Technology Data Exchange (ETDEWEB)

    Sugita, S.; Isojima, Y. [Hachinohe Institute of Technology, Aomori (Japan); Yu, Q. [Wuhan University of Technology, (Taiwan, Province of China)

    1998-05-01

    It is well known that a calcium silicate hydrate, commonly referred to as C-S-H gel, is important for cement to exhibit strength. Silica is present in rice husk ash to around 90%. When sufficiently sintered and crushed, rice husk ash mostly comprises amorphous silica having a large surface area. It is reactive, and is considered to contribute to improvement of concrete strength and durability. In this study, rice husk ash is reacted with calcium hydroxide under hydrothermal conditions or mechanochemical conditions at normal temperature, to synthesize Ca(1.5)SiO(3.5){center_dot}xH2O as one of the calcium silicate hydrates. It has an average particle size of 10{mu}m or smaller, which varies depending on synthesis method and condition. The compound synthesized at 40degC is composed of flocs having a porous structure and large specific surface area, as is the case with a C-S-H gel present in Portland cement paste. It loses the above structure and moisture in the fine pores gradually, when heated, but remains amorphous at up to 750degC. It is transformed into wollastonite, when heated to 780degC. 7 refs., 8 figs., 3 tabs.

  2. Analysis list: ash1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ash1 Cell line + dm3 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash1.1.t...sv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash1.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash...1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/ash1.Cell_line.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Cell_line.gml ...

  3. Analysis list: ash2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ash2 Larvae + dm3 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash2.1.tsv ...http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash2.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/ash...2.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/ash2.Larvae.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Larvae.gml ...

  4. Analysis list: Ash2l [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Ash2l Blood + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2l.1.tsv... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash2l.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ash...2l.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Ash2l.Blood.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Blood.gml ...

  5. Future fly ash marketing; Flugaschevermarktung in der Zukunft

    Energy Technology Data Exchange (ETDEWEB)

    Mauder, R.; Hugot, A. [Evonik Power Minerals GmbH, Dinslaken (Germany)

    2008-07-01

    It can be assumed that the fly ash production volumes will undergo a marked increase over the next few years. The conditions of fly ash production will improve as a result of modern and refurbished power plants, yielding a positive effect on the quality of fly ashes. Other vital parameters of future fly ash marketing are fly ash logistics and the infrastructure of power plants. Basically, economic utilisation of the increased production volumes is possible; however, new and long-term strategies are necessary. (orig.)

  6. Characteristic of fly ash derived-zeolite and its catalytic performance for fast pyrolysis of Jatropha waste.

    Science.gov (United States)

    Vichaphund, S; Aht-Ong, D; Sricharoenchaikul, V; Atong, D

    2014-01-01

    Fly ash from pulp and paper industries was used as a raw material for synthesizing zeolite catalyst. Main compositions of fly ash consisted of 41 wt%SiO2, 20 wt%Al2O3, 14 wt%CaO, and 8 wt% Fe2O3. High content of silica and alumina indicated that this fly ash has potential uses for zeolite synthesis. Fly ash was mixed with 1-3 M NaOH solution. Sodium silicate acting as silica source was added into the solution to obtain the initial SiO2/Al2O3 molar ratio of 23.9. The mixtures were then crystallized at 160 degrees C for 24 and 72 h. Zeolites synthesized after a long synthesis time of 72 h showed superior properties in terms of high crystallinity, less impurity, and small particle size. The catalytic activities of fly ash-derived zeolites were investigated via fast pyrolysis of Jatropha wastes using analytical pyrolysis-gas chromatograph/mass spectrometer (GC/MS). Pyrolysis temperature was set at 500 degrees C with Jatropha wastes to catalyst ratio of 1:1, 1:5, and 1:10. Results showed that higher amounts of catalyst have a positive effect on enhancing aromatic hydrocarbons as well as decreasing in the oxygenated and N-containing compounds. Zeolite Socony Mobil-5 (ZSM-5) treated with 3 M NaOH at 72 h showed the highest hydrocarbon yield of 97.4%. The formation of hydrocarbon led to the high heating value of bio-oils. In addition, the presence of ZSM-5 derived from fly ash contributed to reduce the undesirable oxygenated compounds such as aldehydes, acids, and ketones which cause poor quality of bio-oil to only 0.8% while suppressed N-compounds to 1.7%. Overall, the ZSM-5 synthesized from fly ash proved to be an effective catalyst for catalytic fast pyrolysis application.

  7. 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

  8. Environmental hazards of fluoride in volcanic ash: a case study from Ruapehu volcano, New Zealand

    Science.gov (United States)

    Cronin, Shane J.; Neall, V. E.; Lecointre, J. A.; Hedley, M. J.; Loganathan, P.

    2003-03-01

    The vent-hosted hydrothermal system of Ruapehu volcano is normally covered by a c. 10 million m 3 acidic crater lake where volcanic gases accumulate. Through analysis of eruption observations, granulometry, mineralogy and chemistry of volcanic ash from the 1995-1996 Ruapehu eruptions we report on the varying influences on environmental hazards associated with the deposits. All measured parameters are more dependent on the eruptive style than on distance from the vent. Early phreatic and phreatomagmatic eruption phases from crater lakes similar to that on Ruapehu are likely to contain the greatest concentrations of environmentally significant elements, especially sulphur and fluoride. These elements are contained within altered xenolithic material extracted from the hydrothermal system by steam explosions, as well as in residue hydrothermal fluids adsorbed on to particle surfaces. In particular, total F in the ash may be enriched by a factor of 6 relative to original magmatic contents, although immediately soluble F does not show such dramatic increases. Highly soluble NaF and CaSiF 6 phases, demonstrated to be the carriers of 'available' F in purely magmatic eruptive systems, are probably not dominant in the products of phreatomagmatic eruptions through hydrothermal systems. Instead, slowly soluble compounds such as CaF 2, AlF 3 and Ca 5(PO 4) 3F dominate. Fluoride in these phases is released over longer periods, where only one third is leached in a single 24-h water extraction. This implies that estimation of soluble F in such ashes based on a single leach leads to underestimation of the F impact, especially of a potential longer-term environmental hazard. In addition, a large proportion of the total F in the ash is apparently soluble in the digestive system of grazing animals. In the Ruapehu case this led to several thousand sheep deaths from fluorosis.

  9. Coal ash conversion into effective adsorbents for removal of heavy metals and dyes from wastewater.

    Science.gov (United States)

    Wang, Shaobin; Soudi, Mehdi; Li, Li; Zhu, Z H

    2006-05-20

    Fly ash was modified by hydrothermal treatment using NaOH solutions under various conditions for zeolite synthesis. The XRD patterns are presented. The results indicated that the samples obtained after treatment are much different. The XRD profiles revealed a number of new reflexes, suggesting a phase transformation probably occurred. Both heat treatment and chemical treatment increased the surface area and pore volume. It was found that zeolite P would be formed at the conditions of higher NaOH concentration and temperature. The treated fly ash was tested for adsorption of heavy metal ions and dyes in aqueous solution. It was shown that fly ash and the modified forms could effectively absorb heavy metals and methylene blue but not effectively adsorb rhodamine B. Modifying fly ash with NaOH solution would significantly enhance the adsorption capacity depending on the treatment temperature, time, and base concentration. The adsorption capacity of methylene blue would increases with pH of the dye solution and the sorption capacity of FA-NaOH could reach 5 x 10(-5) mol/g. The adsorption isotherm could be described by the Langmuir and Freundlich isotherm equations. Removal of copper and nickel ions could also be achieved on those treated fly ash. The removal efficiency for copper and nickel ions could be from 30% to 90% depending on the initial concentrations. The increase in adsorption temperature will enhance the adsorption efficiency for both heavy metals. The pseudo second-order kinetics would be better for fitting the dynamic adsorption of Cu and Ni ions.

  10. 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.

  11. Content Distribution for Telecom Carriers

    Directory of Open Access Journals (Sweden)

    Ben Falchuk

    2006-08-01

    Full Text Available Distribution of digital content is a key revenue opportunity for telecommunications carriers. As media content moves from analog and physical media-based distribution to digital on-line distribution, a great opportunity exists for carriers to claim their role in the media value chain and grow revenue by enhancing their broadband “all you can eat” high speed Internet access offer to incorporate delivery of a variety of paid content. By offering a distributed peer to peer content delivery capability with authentication, personalization and payment functions, carriers can gain a larger portion of the revenue paid for content both within and beyond their traditional service domains. This paper describes an approach to digital content distribution that leverages existing Intelligent Network infrastructure that many carriers already possess, as well as Web Services.

  12. Residual Ash Formation during Suspension-Firing of Biomass

    DEFF Research Database (Denmark)

    Damø, Anne Juul; Jappe Frandsen, Flemming; Jensen, Peter Arendt

    2014-01-01

    Through 50+ years, high quality research has been conducted in order to characterize ash and deposit formation in utility boilers fired with coal, biomass and waste fractions. The basic mechanism of fly ash formation in suspension fired coal boilers is well described, documented and may even...... be modeled relatively precisely. Concerning fly ash formation from biomass or waste fractions, the situation is not nearly as good. Lots of data are available from campaigns where different ash fractions, including sometimes also in-situ ash, have been collected and analyzed chemically and for particle size...... distribution. Thus, there is a good flair of the chemistry of fly ash formed in plants fired with biomass or waste fractions, either alone, or in conjunction with coal. But data on dedicated studies of the physical size development of fly ash, are almost non-existing for biomasses and waste fractions...

  13. Fly ash of mineral coal as ceramic tiles raw material.

    Science.gov (United States)

    Zimmer, A; Bergmann, C P

    2007-01-01

    The aim of this work was to evaluate the use of mineral coal fly ash as a raw material in the production of ceramic tiles. The samples of fly ash came from Capivari de Baixo, a city situated in the Brazilian Federal State of Santa Catarina. The fly ash and the raw materials were characterized regarding their physical chemical properties, and, based on these results; batches containing fly ash and typical raw materials for ceramic tiles were prepared. The fly ash content in the batches varied between 20 and 80 wt%. Specimens were molded using a uniaxial hydraulic press and were fired. All batches containing ash up to 60 wt% present adequate properties to be classified as several kinds of products in the ISO 13006 standard () regarding its different absorption groups (pressed). The results obtained indicate that fly ash, when mixed with traditional raw materials, has the necessary requirements to be used as a raw material for production of ceramic tiles.

  14. Experimental study on fly ash capture mercury in flue gas

    Institute of Scientific and Technical Information of China (English)

    Mercedes; DíAZ-SOMOANO; Patricia; ABAD-VALLE; M.Rosa; MARTíNEZ-TARAZONA

    2010-01-01

    Systematic experiments were conducted on a fixed-bed reactor to investigate the interaction between fly ash and mercury,the results implied that fly ash can capture mercury effectively.Among different fly ashes,the unburned carbon in the FA2 and FA3 fly ashes has the highest mercury capture capacity,up to 10.3 and 9.36 μg/g,respectively,which is close to that of commercial activated carbon.There is no obvious relationship between mercury content and carbon content or BET surface area of fly ash.Petrography classification standard was applied to distinguish fly ash carbon particles.Carbon content is not the only variable that controls mercury capture on fly ash,there are likely significant differences in the mercury capture capacities of the various carbon forms.Mercury capture capacity mainly depends on the content of anisotropy carbon particles with porous network structure.

  15. Volcanic Ash fall Impact on Vegetation, Colima 2005

    Science.gov (United States)

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

    2007-05-01

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

  16. Development of a modeling approach to predict ash formation during co-firing of coal and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Doshi, V. [School of Engineering, Monash University Sunway Campus, Jalan Lagoon Selatan, Bandar Sunway, Selangor (Malaysia); Vuthaluru, H.B. [Curtin University of Technology, Kent Street, Bentley 6104, Perth, Western Australia (Australia); Korbee, R. [HRL Technology, Ipswich, Queensland (Australia); Kiel, J.H.A. [ECN Biomass, Coal and Environmental Research, P.O. Box 1, 1755 ZG Petten (Netherlands)

    2009-09-15

    The scope of this paper includes the development of a modelling approach to predict the ash release behaviour and chemical composition of inorganics during co-firing of coal and biomass. In the present work, an advanced analytical method was developed and introduced to determine the speciation of biomass using pH extraction analysis. Biomass samples considered for the study include wood chips, wood bark and straw. The speciation data was used as an input to the chemical speciation model to predict the behaviour and release of ash. It was found that the main gaseous species formed during the combustion of biomass are KCl, NaCl, K{sub 2}SO{sub 4} and Na{sub 2}SO{sub 4}. Calculations of gas-to-particle formation were also carried out to determine the chemical composition of coal and biomass during cooling which takes place in the boiler. It was found that the heterogeneous condensation occurring on heat exchange surfaces of boilers is much more than homogeneous condensation. Preliminary studies of interaction between coal and biomass during ash formation process showed that Al, Si and S elements in coal may have a 'buffering' effect on biomass alkali metals, thus reducing the release of alkali-gases which act as precursors to ash deposition and corrosion during co-firing. The results obtained in this work are considered to be valuable and form the basis for accurately determining the ash deposition during co-firing. (author)

  17. Modeling calcium dissolution from oil shale ash: Part 1. Ca dissolution during ash washing in a batch reactor

    Energy Technology Data Exchange (ETDEWEB)

    Velts, O.; Kallas, J. [Tallinn University of Technology, Laboratory of Inorganic Materials, 5 Ehitajate Str., Tallinn 19086 (Estonia); Lappeenranta University of Technology, Laboratory of Separation Technology, Skinnarilankatu 34, Lappeenranta 53851 (Finland); Hautaniemi, M. [Lappeenranta University of Technology, Laboratory of Separation Technology, Skinnarilankatu 34, Lappeenranta 53851 (Finland); Kuusik, R. [Tallinn University of Technology, Laboratory of Inorganic Materials, 5 Ehitajate Str., Tallinn 19086 (Estonia)

    2010-05-15

    Batch dissolution experiments were carried out to investigate Ca leachability from oil shale ashes formed in boilers operating with different combustion technologies. The main characteristics of Ca dissolution equilibrium and dynamics, including Ca internal mass transfer through effective diffusion coefficients inside the ash particle were evaluated. Based on the collected data, models allowing simulation of the Ca dissolution process from oil shale ashes during ash washing in a batch reactor were developed. The models are a set of differential equations that describe the changes in Ca content in the solid and liquid phase of the ash-water suspension. (author)

  18. Natural rain - induced element leaching from coal ASH; La pluie naturelle - lixiviation d'element de la cendre de charbon

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, A.; Djordjevic, D.; Polic, P. [Belgrade Univ., Dept. of Chemistry, IChTM, Chemistry Center, Belgrade (Yugoslavia)

    2000-07-01

    Six composite samples of coal ash from power plants 'Nikola Tesla' A and B, located in the vicinity of Obrenovac, near Belgrade (Yugoslavia), were subjected to extraction with 1 M acetate solution, pH 5.5, in order to imitate possible leaching of the ash by natural acidic rain. Seven trace and five major elements have been examined, and the obtained amounts were in the range from 0.003 {+-} 0.001 ppm (Cd), to 117 {+-} 27 ppm (Ca), dry ash basis. Though some of the concentrations were higher than allowed by domestic and international regulations it can be concluded that neither of the examined elements represents a serious threat for the environment (at least for the conditions applied in this experiment). Also, both magnesium and iron are carriers of copper, chromium and arsenic, while cadmium is associated with magnesium and manganese. Calcium and manganese are beside magnesium and iron, scavengers of arsenic. (authors)

  19. Comparison of emerald ash borer preference for ash of different species, sun exposure, age, and stress treatments in relation to foliar volatiles and nutrition

    Science.gov (United States)

    Therese M. Poland; Deepa S. Pureswaran; Yigen Chen

    2009-01-01

    We investigated the host selection behavior and feeding preference of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) on six different species of ash including Manchurian ash (F...

  20. Heat Waves

    Science.gov (United States)

    Heat Waves Dangers we face during periods of very high temperatures include: Heat cramps: These are muscular pains and ... having trouble with the heat. If a heat wave is predicted or happening… - Slow down. Avoid strenuous ...

  1. Heat Islands

    Science.gov (United States)

    EPA's Heat Island Effect Site provides information on heat islands, their impacts, mitigation strategies, related research, a directory of heat island reduction initiatives in U.S. communities, and EPA's Heat Island Reduction Program.

  2. Carrier currents systems and home integrated systems; Les courants porteurs vont-ils epanouir la domotique

    Energy Technology Data Exchange (ETDEWEB)

    Remond, C.

    1996-12-31

    Energy savings in buildings can be performed by remote control applications. Current carrier equipment interfaces use buildings integrated power network to perform data transmission through an entire building, or even to a remote building. The case of industrial buildings lighting systems is sketched out, but these interfaces apply as well to electric heating (space or water heating). (D.L.)

  3. Mapping ash properties using principal components analysis

    Science.gov (United States)

    Pereira, Paulo; Brevik, Eric; Cerda, Artemi; Ubeda, Xavier; Novara, Agata; Francos, Marcos; Rodrigo-Comino, Jesus; Bogunovic, Igor; Khaledian, Yones

    2017-04-01

    In post-fire environments ash has important benefits for soils, such as protection and source of nutrients, crucial for vegetation recuperation (Jordan et al., 2016; Pereira et al., 2015a; 2016a,b). The thickness and distribution of ash are fundamental aspects for soil protection (Cerdà and Doerr, 2008; Pereira et al., 2015b) and the severity at which was produced is important for the type and amount of elements that is released in soil solution (Bodi et al., 2014). Ash is very mobile material, and it is important were it will be deposited. Until the first rainfalls are is very mobile. After it, bind in the soil surface and is harder to erode. Mapping ash properties in the immediate period after fire is complex, since it is constantly moving (Pereira et al., 2015b). However, is an important task, since according the amount and type of ash produced we can identify the degree of soil protection and the nutrients that will be dissolved. The objective of this work is to apply to map ash properties (CaCO3, pH, and select extractable elements) using a principal component analysis (PCA) in the immediate period after the fire. Four days after the fire we established a grid in a 9x27 m area and took ash samples every 3 meters for a total of 40 sampling points (Pereira et al., 2017). The PCA identified 5 different factors. Factor 1 identified high loadings in electrical conductivity, calcium, and magnesium and negative with aluminum and iron, while Factor 3 had high positive loadings in total phosphorous and silica. Factor 3 showed high positive loadings in sodium and potassium, factor 4 high negative loadings in CaCO3 and pH, and factor 5 high loadings in sodium and potassium. The experimental variograms of the extracted factors showed that the Gaussian model was the most precise to model factor 1, the linear to model factor 2 and the wave hole effect to model factor 3, 4 and 5. The maps produced confirm the patternd observed in the experimental variograms. Factor 1 and 2

  4. Mechanical and thermal properties of prepacked aggregate concrete incorporating palm oil fuel ash

    Indian Academy of Sciences (India)

    HOSSEIN MOHAMMADHOSSEINI; A S M ABDUL AWAL; ABDUL RAHMAN MOHD SAM

    2016-10-01

    Prepacked aggregate concrete (PAC) is a special type of concrete which is made by placing coarse aggregate in a formwork and injecting a grout either by pump or under the gravity force to fill the voids. Use of pozzolanic materials in conventional concrete has become increasingly extensive, and this trend is expected to continue in PAC as well. Palm oil fuel ash (POFA) is one of these pozzolanic ash, which has been recognized as a good pozzolanic material. This paper presents the experimental results of the performance behaviour of POFA in developing physical and mechanical properties of prepacked aggregate concrete. Four concrete mixes namely,prepacked concrete with 100% OPC as a control, and PAC with 10, 20 and 30% POFA were cast, and thetemperature growth due to heat of hydration and heat transfer in all the mixtures was recorded. It has been found that POFA significantly reduces the temperature rise in prepacked aggregate concrete and delay the transfer of heat to the concrete body. The compressive and tensile strengths, however, increased with replacement up to20% POFA. The results obtained and the observation made in this study suggest that the replacement of OPC by POFA is beneficial, particularly for prepacked mass concrete where thermal cracking due to extreme heat rise is of great concern.

  5. Effects of nano-SiO(2) and different ash particle sizes on sludge ash-cement mortar.

    Science.gov (United States)

    Lin, K L; Chang, W C; Lin, D F; Luo, H L; Tsai, M C

    2008-09-01

    The effects of nano-SiO(2) on three ash particle sizes in mortar were studied by replacing a portion of the cement with incinerated sewage sludge ash. Results indicate that the amount of water needed at standard consistency increased as more nano-SiO(2) was added. Moreover, a reduction in setting time became noticeable for smaller ash particle sizes. The compressive strength of the ash-cement mortar increased as more nano-SiO(2) was added. Additionally, with 2% nano-SiO(2) added and a cure length of 7 days, the compressive strength of the ash-cement mortar with 1 microm ash particle size was about 1.5 times better that of 75microm particle size. Further, nano-SiO(2) functioned to fill pores for ash-cement mortar with different ash particle sizes. However, the effects of this pore-filling varied with ash particle size. Higher amounts of nano-SiO(2) better influenced the ash-cement mortar with larger ash particle sizes.

  6. One-Pot Synthesis of GeAs Ultrafine Particles from Coal Fly Ash by Vacuum Dynamic Flash Reduction and Inert Gas Condensation.

    Science.gov (United States)

    Zhang, Lingen; Xu, Zhenming

    2017-06-16

    Ge-monopnictides (GeAs) plays critical role in high-tech industry, especially in the field of advanced optical devices and infrared. As a secondary material, coal fly ash could be further recycled to retrieve germanium and prepare GeAs material with high added values. Hence, the aim of this paper is to propose a one-pot synthesis that uses vacuum flash reduction and inert-gas consolidation method to prepare GeAs ultrafine particles. Germanium in coal fly ash can be successfully recycled; simultaneously, GeAs ultrafine particles were prepared. Separation principle and feasibility of this process was discussed. Temperature, carrier gas flow rate and system pressure were the major factors on formation, morphology and distribution of particle size of GeAs ultrafine particles. A three steps synthetic mechanism was clarified, namely, thermal rupture of coal fly ash and release of GeO2 and As2O3, the gas-solid phase reaction of GeO2, As2O3 and coke to generate metallic Ge and As in vacuum flash reduction. Meantime, GeAs were produced in the gas phase reaction. Finally, GeAs ultrafine particles were obtained by carrier gas condensation. In short, this research developed a practical and environment-friendly one-pot synthesis to recycle germanium in coal fly ash and prepare GeAs ultrafine particles with high added values.

  7. FUNDAMENTAL STUDY OF LOW-NOx COMBUSTION FLY ASH UTILIZATION

    Energy Technology Data Exchange (ETDEWEB)

    ERIC M. SUUBERG; ROBERT H. HURT

    1998-10-19

    This study is principally concerned with characterizing the organic part of coal combustion fly ashes. High carbon fly ashes are becoming more common as by-products of low-NOx combustion technology, and there is need to learn more about this fraction of the fly ash. The project team consists of two universities, Brown and Princeton, and an electrical utility, New England Power. A sample suite of over fifty fly ashes has been gathered from utilities across the United States, and includes ashes from a coals ranging in rank from bituminous to lignite. The characterizations of these ashes include standard tests (LOI, Foam Index), as well as more detailed characterizations of their surface areas, porosity, extractability and adsorption behavior. The ultimate goal is, by better characterizing the material, to enable broadening the range of applications for coal fly ash re-use beyond the current main market as a pozzolanic agent for concretes. The potential for high carbon-content fly ashes to substitute for activated carbons is receiving particular attention. The work performed to date has already revealed how very different the surfaces of different ashes produced by the same utility can be, with respect to polarity of the residual carbon. This can help explain the large variations in acceptability of these ashes as concrete additives.

  8. A review on the utilization of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    M. Ahmaruzzaman [National Institute of Technology Silchar, Silchar (India). Department of Chemistry

    2010-06-15

    Fly ash, generated during the combustion of coal for energy production, is an industrial by-product which is recognized as an environmental pollutant. Because of the environmental problems presented by the fly ash, considerable research has been undertaken on the subject worldwide. In this paper, the utilization of fly ash in construction, as a low-cost adsorbent for the removal of organic compounds, flue gas and metals, light weight aggregate, mine back fill, road sub-base, and zeolite synthesis is discussed. A considerable amount of research has been conducted using fly ash for adsorption of NOx, SOx, organic compounds, and mercury in air, dyes and other organic compounds in waters. It is found that fly ash is a promising adsorbent for the removal of various pollutants. The adsorption capacity of fly ash may be increased after chemical and physical activation. It was also found that fly ash has good potential for use in the construction industry. The conversion of fly ash into zeolites has many applications such as ion exchange, molecular sieves, and adsorbents. Converting fly ash into zeolites not only alleviates the disposal problem but also converts a waste material into a marketable commodity. Investigations also revealed that the unburned carbon component in fly ash plays an important role in its adsorption capacity. Future research in these areas is also discussed. 428 refs., 3 figs., 7 tabs.

  9. A review on the utilization of fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Ahmaruzzaman, M. [Department of Chemistry, National Institute of Technology Silchar, Silchar-788010, Assam (India)

    2010-06-15

    Fly ash, generated during the combustion of coal for energy production, is an industrial by-product which is recognized as an environmental pollutant. Because of the environmental problems presented by the fly ash, considerable research has been undertaken on the subject worldwide. In this paper, the utilization of fly ash in construction, as a low-cost adsorbent for the removal of organic compounds, flue gas and metals, light weight aggregate, mine back fill, road sub-base, and zeolite synthesis is discussed. A considerable amount of research has been conducted using fly ash for adsorption of NO{sub x}, SO{sub x}, organic compounds, and mercury in air, dyes and other organic compounds in waters. It is found that fly ash is a promising adsorbent for the removal of various pollutants. The adsorption capacity of fly ash may be increased after chemical and physical activation. It was also found that fly ash has good potential for use in the construction industry. The conversion of fly ash into zeolites has many applications such as ion exchange, molecular sieves, and adsorbents. Converting fly ash into zeolites not only alleviates the disposal problem but also converts a waste material into a marketable commodity. Investigations also revealed that the unburned carbon component in fly ash plays an important role in its adsorption capacity. Future research in these areas is also discussed. (author)

  10. Generation of volcanic ash: a textural study of ash produced in various laboratory experiments

    Science.gov (United States)

    Lavallée, Yan; Kueppers, Ulrich; Dingwell, Donald B.

    2010-05-01

    In volcanology, ash is commonly understood as a fragment of a bubble wall that gets disrupted during explosive eruptions. Most volcanic ashes are indeed the product of explosive eruptions, but the true definition is however that of a particle size being inferior to 2 mm. The term does not hold any information about its genesis. During fragmentation, particles of all sizes in various amounts are generated. In nature, fragmentation is a brittle response of the material (whether a rock or magma) caused by changes in 1) strain rate and 2) temperature, and/or 3) chemical composition. Here we used different experimental techniques to produce ash and study their physical characteristics. The effects of strain rate were investigated by deforming volcanic rocks and magma (pure silicate melt and crystal-bearing magma) at different temperatures and stresses in a uniaxial compression apparatus. Failure of pure silicate melts is spontaneous and generates more ash particles than fragmentation of crystal-bearing melts. In the latter, the abundance of generated ash correlates positively with the strain rate. We complemented this investigation with a study of particles generated during rapid decompression of porous rocks, using a fragmentation apparatus. Products of decompression experiments at different initial applied pore pressure show that the amount of ash generated by bubble burst increase with the initial applied pressure and the open porosity. The effects of temperature were investigated by dropping pure silicate melts and crystal-bearing magma at 900 and 1100°C in water at room temperature. Quenching of the material is accompanied by rapid contraction and near instantaneous fragmentation. Pure silicate melts respond more violently to the interaction with water and completely fragmented into small particles, including a variety of ash morphologies and surface textures. Crystal-bearing magmas however fragmented only very partially when in contact with water and produced a

  11. Sustainable use of biofuel by recycling ash to forests: treatment of biofuel ash.

    Science.gov (United States)

    Mahmoudkhani, Maryam; Richards, Tobias; Theliander, Hans

    2007-06-01

    The influence of treatment techniques on leaching properties of alkaline species from biofuel ash is investigated in this paper. Ash samples from combustion of biofuels in a circulating fluidized bed and grate-firing combustion plants are studied. The samples are treated using three different treatment techniques; self-hardening, thermal treatment, and hardening bythe addition of binding materials. Nontreated and treated samples are evaluated for the leaching properties of the alkaline compounds and, furthermore, are characterized with respect to both physical and chemical characteristics. The results show the influence of treatment techniques on the physical structure and leaching characteristics of alkaline species. Results also indicate that ash samples show different behavior when treated with different methods, i.e., the influence of treatment technique on controlling the leaching properties is highly dependent on the initial chemical composition of ash. It was also found that there is an interaction between leaching of limited and easily soluble species, e.g., calcium and potassium leaching. Therefore, to control the leaching rate of alkaline species from ash, the characteristics that correlate the leaching properties of both easily and limited soluble species need to be adjusted.

  12. Evaluation of the leaching characteristics of wood ash and the influence of ash agglomeration

    Energy Technology Data Exchange (ETDEWEB)

    Steenari, B.-M.; Lindqvist, O. [Chalmers University of Technology, Goeteborg (Sweden); Karlsson, L.G. [Kemakta Consulting AB, Stockholm (Sweden)

    1999-11-01

    The release of mineral nutrients and other species from untreated and stabilised wood ash has been investigated. Stabilisation is applied with the aim to modify the solubility of ash components and the ash particle size, i.e. to form dense ash particle agglomerates. This process induces the formation of several secondary minerals. The most important reaction is the transformation of Ca(OH){sub 2} into CaCO{sub 3} which lowers the calcium leaching rate significantly. A significant fraction of the alkali metals, K and Na, is present in salts which are rapidly released. The short-term release of these salts, as simulated in laboratory experiments, was not reduced by the stabilisation methods applied. Generally, low leaching rates were observed for the important plant nutrients P and Mg as well as for Fe and other metals from both untreated and agglomerated ashes. Thermodynamics equilibrium modelling of the hardening process showed that in addition to the transformation of Ca(OH){sub 2} to CaCO{sub 3}, formation of the mineral ettringite is possible at a high pH. Experimental results have confirmed this. As the pH in the pore solution decreases during long-term leaching ettringite will be transformed into calcium carbonate and gypsum. In accordance with the experimental results, no formation of secondary solubility controlling potassium or sodium minerals was indicated by the modelling results. (author)

  13. TECHNOLOGY AND EFFICIENT USE OF PEAT ASH IN MASTICS FOR WATERPROOFING OF BRIDGE AND TUNNEL STRUCTURES

    Directory of Open Access Journals (Sweden)

    G. D. Lyahevich

    2015-01-01

    Full Text Available A prospective method for protection of  bridges and tunnels against aggressive water action is surface waterproofing on the basis of an organo-mineral binder. Its structural strength can be increased by introduction of particles which are similar to the size of  asphaltenes and an elasticity of disperse medium has been increased due to introduction of polymers. These theoretical suppositions point out the possibility for simultaneous provision of flexibility at low temperatures and high heat resistance for mastics on the basis  of organo-mineral binders. In this regard a goal has been set to obtain a mastic high flexibility and high heat resistance  while using finely divided activated peat ash.Rubber crushed in accordance with ТУ (Technical Specifications 38.108035–87,  divinyl-styrene thermoelastoplast DСT-30Р-20ПС,  bitumen of grade 20/30 in accordance with СТБ ЕН 12591–2010, ash from burning peat at the Lida Peat Briquette Plant, multi-purpose industrial oil of solvent refining with high viscosity index, super-plasticizer – sodium salt which is a condensation product of aromatic carbon sulfo-oxidation with formaldehyde and neutralization with the help of sodium hydroxide (type 1 have been used in order to obtain the stated objective. While using these materials compositions and technology for preparation of organo-mineral mastics have been developed in the paper. Their tests have shown that a modification of finely divided  mastics carried out with the help of peat ash which is activated by super-plasticizer НСПКСАУсФ-1, various polymer additives, contributes to an increase in their heat resistance, elasticity, water resistance, and also allows to control their technological and operational characteristics. The paper has experimentally confirmed that peat ash can be successfully used for preparation of high-quality waterproofing mastics which are so necessary for  protection of bridge and tunnel

  14. Simualting the Phase Separated rp-ash

    Science.gov (United States)

    Caplan, Matthew; Horowitz, Chuck; Berry, Donald

    2017-01-01

    The composition and phase separation of rp-ash on accreting neutron stars determine the thermal properties of the crust which must be understood to interpret observations of crust cooling in X-ray bursts. In this work, we report on recent large scale molecular dynamics simulations of the outer crust. Using the crust compositions calculated by Mckinven et al. 2016, we study the structure of the crystal that forms, as well as diffusion and thermal properties of the crust.

  15. Bacterial Carriers for Glioblastoma Therapy

    Directory of Open Access Journals (Sweden)

    Nalini Mehta

    2017-03-01

    Full Text Available Treatment of aggressive glioblastoma brain tumors is challenging, largely due to diffusion barriers preventing efficient drug dosing to tumors. To overcome these barriers, bacterial carriers that are actively motile and programmed to migrate and localize to tumor zones were designed. These carriers can induce apoptosis via hypoxia-controlled expression of a tumor suppressor protein p53 and a pro-apoptotic drug, Azurin. In a xenograft model of human glioblastoma in rats, bacterial carrier therapy conferred a significant survival benefit with 19% overall long-term survival of >100 days in treated animals relative to a median survival of 26 days in control untreated animals. Histological and proteomic analyses were performed to elucidate the safety and efficacy of these carriers, showing an absence of systemic toxicity and a restored neural environment in treated responders. In the treated non-responders, proteomic analysis revealed competing mechanisms of pro-apoptotic and drug-resistant activity. This bacterial carrier opens a versatile avenue to overcome diffusion barriers in glioblastoma by virtue of its active motility in extracellular space and can lead to tailored therapies via tumor-specific expression of tumoricidal proteins.

  16. Low-cost carriers fare competition effect

    NARCIS (Netherlands)

    Carmona Benitez, R.B.; Lodewijks, G.

    2010-01-01

    This paper examines the effects that low-cost carriers (LCC’s) produce when entering new routes operated only by full-service carriers (FSC’s) and routes operated by low-cost carriers in competition with full-service carriers. A mathematical model has been developed to determine what routes should b

  17. Impact of carrier heating on backscattering in inversion layers

    Science.gov (United States)

    Clerc, R.; Palestri, P.; Selmi, L.; Ghibaudo, G.

    2011-11-01

    In this work, Monte Carlo simulations and analytical modeling are used to investigate quasi-ballistic transport in nanometric metal oxide semiconductor field effect transistors (MOSFETs). In particular, we examine how the thermal nature of the distribution functions, which is implicitly assumed in the most common expression for the backscattering coefficient, leads to an underestimation of the backscattering coefficient in high field conditions and erroneous velocity distribution along the channel. An improved analytical model is proposed, which better captures the nonequilibrium nature of the distribution function and its impact on backscattering and by allowing velocity profiles to exceed the thermal limit. The improved model provides additional insights on the impact of several assumptions on backscattering and could serve as the basis for the development of physically based compact models of quasi-ballistic MOSFETs.

  18. FTIR analysis of ash in wine

    Directory of Open Access Journals (Sweden)

    Jug Tjaša

    2017-01-01

    Full Text Available In a modern oenological laboratory determination of ash is a limiting factor regarding the speed of analysis, since functional FTIR analysis of ash are not common yet. Therefore 324 samples were analysed by FTIR spectroscopy on TDI Bacchus 3 as well as ISO 17025 accredited reference method (OIV–MA–AS2–04: R2009 in two duplicates. FTIR spectra and reference data were uploaded into software for the calibration development and validation performed. Already the original TDI calibration was ready to use, showing satisfying results. However, we tried to improve it. On 324 spectra, we have looked for optimal wavelengths and mathematical models, which gave the best results. The developed calibration was then confirmed by method validation: repeatability, reproducibility and accuracy. The expanded measurement uncertainty calculated was 0.3 g/L, which I slightly higher than of the reference method used. We have found another advantage over classical method: there is no influence of the air pressure or moisture. Nevertheless, we were able to confirm that our reference method was free of systematic error induced by the influence of the weather. Anyway, we can conclude that analysis of ash in wine by FTIR spectroscopy is a promising, fast and reliable new method.

  19. Market assessment of PFBC ash use

    Energy Technology Data Exchange (ETDEWEB)

    Bland, A. E.; Brown, T. H., Western Research Institute

    1998-01-01

    Pressurized fluidized bed combustion (PFBC) of coal is undergoing demonstration in the United States, as well as throughout the world. American Electric Power`s (AEP`s) bubbling PFBC 70 MWe Tidd demonstration program in Ohio and pilot-scale development at Foster Wheeler Energia Oy 10 MWth circulating PFBC at Karhula, Finland, have demonstrated the advantages of PFBC technology. Further technology development in the US is planned with the deployment of the technology at the MacIntosh Clean Coal project in Lakeland, Florida. Development of uses for solid wastes from PFBC coal-fired power systems is being actively pursued as part of the demonstration of PFBC technologies. Ashes collected from Foster Wheeler Energia Oy pilot circulating PFBC tests in Karhula, Finland, operating on (1) low sulfur subbituminous and (2) high sulfur bituminous coal; and ash from the AEP`s high-sulfur bituminous coal-fired bubbling PFBC in Brilliant, Ohio, were evaluated in laboratory and pilot-scale ash use testing at Western Research Institute (WRI).

  20. Determining Heats of Combustion of Gaseous Hydrocarbons

    Science.gov (United States)

    Singh, Jag J.; Sprinkle, Danny R.; Puster, Richard L.

    1987-01-01

    Enrichment-oxygen flow rate-ratio related to heat of combustion. Technique developed for determining heats of combustion of natural-gas samples. Based on measuring ratio m/n, where m is (volmetric) flow rate of oxygen required to enrich carrier air in which test gas flowing at rate n is burned, such that mole fraction of oxygen in combustion-product gases equals that in carrier air. The m/n ratio directly related to heats of combustion of saturated hydrocarbons present in natural gas.

  1. Test and evaluation of the heat recovery incinerator system at Naval Station, Mayport, Florida

    Science.gov (United States)

    1981-05-01

    This report describes test and evaluation of the two-ton/hr heat recovery incinerator (HRI) facility located at Mayport Naval Station, Fla., carried out during November and December 1980. The tests included: (1) Solid Waste: characterization, heating value, and ultimate analysis, (2) Ash: moisture, combustibles, and heating values of both bottom and cyclone ashes; Extraction Procedure toxicity tests on leachates from both bottom and cyclone ashes; trace metals in cyclone particulates, (3) Stack Emissions: particulates (quantity and size distribution), chlorides, oxygen, carbon dioxide, carbon monoxide, and trace elements, and (4) Heat and Mass Balance: all measurements required to carry out complete heat and mass balance calculations over the test period. The overall thermal efficiency of the HRI facility while operating at approximately 1.0 ton/hr was found to be 49% when the primary Btu equivalent of the electrical energy consumed during the test program was included.

  2. 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.

  3. Crowdsourcing genomic analyses of ash and ash dieback – power to the people

    Directory of Open Access Journals (Sweden)

    MacLean Dan

    2013-02-01

    Full Text Available Abstract Ash dieback is a devastating fungal disease of ash trees that has swept across Europe and recently reached the UK. This emergent pathogen has received little study in the past and its effect threatens to overwhelm the ash population. In response to this we have produced some initial genomics datasets and taken the unusual step of releasing them to the scientific community for analysis without first performing our own. In this manner we hope to ‘crowdsource’ analyses and bring the expertise of the community to bear on this problem as quickly as possible. Our data has been released through our website at oadb.tsl.ac.uk and a public GitHub repository.

  4. Biofuel Combustion Fly Ash Influence on the Properties of Concrete

    Directory of Open Access Journals (Sweden)

    Aurelijus Daugėla

    2016-02-01

    Full Text Available Cement as the binding agent in the production of concrete can be replaced with active mineral admixtures. Biofuel combustion fly ash is one of such admixtures. Materials used for the study: Portland cement CEM I 42.5 R, sand of 0/4 fraction, gravel of 4/16 fraction, biofuel fly ash, superplasticizer, water. Six compositions of concrete were designed by replacing 0%, 5%, 10%, 15% 20%, and 25% of cement with biofuel fly ash. The article analyses the effect of biofuel fly ash content on the properties of concrete. The tests revealed that the increase of biofuel fly ash content up to 20% increases concrete density and compressive strength after 7 and 28 days of curing and decreases water absorption, with corrected water content by using plasticizing admixture. It was found that concrete where 20% of cement is replaced by biofuel ash has higher frost resistance.

  5. Risk assessment of replacing conventional P fertilizers with biomass ash

    DEFF Research Database (Denmark)

    Cruz Paredes, Carla; Lopez Garcia, Alvaro; Rubæk, Gitte H.;

    2017-01-01

    Reutilizing biomass ashes in agriculture can substitute inputs of P from finite primary sources. However, recycling of ashes is disputed due to their content of toxic substances such as heavy metals. This study evaluates the potential risk of replacing easily soluble inorganic P fertilizer with P...... application, grain, straw and root dry matter yield, and P and Cd uptake were determined. Resin-extractable P was measured in soil and the symbiotic arbuscular mycorrhizal fungal activity, colonization, and community composition were assessed. Crop yield was not affected by ash application, while P......-uptake and mycorrhizal status were slightly enhanced with high ash applications. Changes to the mycorrhizal community composition were evident with high ash doses. Cadmium uptake in aboveground plant tissue was unaffected by ash treatments, but increased in roots with increasing doses. Consequently, we conclude...

  6. Environmental impact of using fly ash in concrete

    Energy Technology Data Exchange (ETDEWEB)

    1978-09-01

    An attempt was made to estimate the chemical composition of fly ash using the known chemical composition of coals from numerous regions of the country and the known behavior of elements in a limited number of coal and fly-ash samples. This technique assumes that each element in every piece of coal in the United States partitions itself into fly ash to the same extent and leaches from fly ash at the same rate. Using these limited data, enrichment factors were then calculated by dividing the composition in the fly ash by the composition in the corresponding coal samples. These enrichment factors were then applied to all of the coal samples for which chemical compositions were available to estimate the chemical composition of the fly ash.

  7. Volcanic ash as an oceanic iron source and sink

    Science.gov (United States)

    Rogan, Nicholas; Achterberg, Eric P.; Le Moigne, Frédéric A. C.; Marsay, Chris M.; Tagliabue, Alessandro; Williams, Richard G.

    2016-03-01

    Volcanic ash deposition to the ocean forms a natural source of iron (Fe) to surface water microbial communities. Inputs of lithogenic material may also facilitate Fe removal through scavenging. Combining dissolved Fe (dFe) and thorium-234 observations alongside modeling, we investigate scavenging of Fe in the North Atlantic following the Eyjafjallajökull volcanic eruption. Under typical conditions biogenic particles dominate scavenging, whereas ash particles dominate during the eruption. The size of particles is important as smaller scavenging particles can become saturated with surface-associated ions. Model simulations indicate that ash deposition associated with Eyjafjallajökull likely led to net Fe removal. Our model suggests a threefold greater stimulation of biological activity if ash deposition had occurred later in the growing season when the region was Fe limited. The implications of ash particle scavenging, eruption timing, and particle saturation need to be considered when assessing the impact of ash deposition on the ocean Fe cycle and productivity.

  8. Modeling and Control of Heat Networks with Storage : the Single-Producer Multiple-Consumer Case

    NARCIS (Netherlands)

    Scholten, Tjeert Wobko; De Persis, Claudio; Tesi, Pietro

    2015-01-01

    In heat networks, energy storage is a viable approach to balance demand and supply. In such a network, a heat carrier is used in the form of water, where heat is injected and extracted through heat exchangers. The network can transport and store heated water in stratification tanks to shift loads in

  9. Feeding by emerald ash borer larvae induces systemic changes in black ash foliar chemistry.

    Science.gov (United States)

    Chen, Yigen; Whitehill, Justin G A; Bonello, Pierluigi; Poland, Therese M

    2011-11-01

    The exotic wood-boring pest, emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), has been threatening North American ash (Fraxinus spp.) resources, this being recognized since its first detection in Michigan, USA and Ontario, Canada in 2002. Ash trees are killed by larval feeding in the cambial region, which results in disruption of photosynthate and nutrient translocation. In this study, changes in volatile and non-volatile foliar phytochemicals of potted 2-yr-old black ash, Fraxinus nigra Marshall, seedlings were observed in response to EAB larval feeding in the main stem. EAB larval feeding affected levels of six compounds [hexanal, (E)-2-hexenal, (Z)-3-hexenyl acetate, (E)-β-ocimene, methyl salicylate, and (Z,E)-α-farnesene] with patterns of interaction depending upon compounds of interest and time of observation. Increased methyl salicylate emission suggests similarity in responses induced by EAB larval feeding and other phloem-feeding herbivores. Overall, EAB larval feeding suppressed (Z)-3-hexenyl acetate emission, elevated (E)-β-ocimene emission in the first 30days, but emissions leveled off thereafter, and generally increased the emission of (Z,E)-α-farnesene. Levels of carbohydrates and phenolics increased overall, while levels of proteins and most amino acids decreased in response to larval feeding. Twenty-three amino acids were consistently detected in the foliage of black ash. The three most abundant amino acids were aspartic acid, glutamic acid, glutamine, while the four least abundant were α-aminobutyric acid, β-aminoisobutyric acid, methionine, and sarcosine. Most (16) foliar free amino acids and 6 of the 9 detected essential amino acids decreased with EAB larval feeding. The ecological consequences of these dynamic phytochemical changes on herbivores harbored by ash trees and potential natural enemies of these herbivores are discussed.

  10. Ash chemistry and sintering, verification of the mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Skrifvars, B.J. [Aabo Akademi, Turku (Finland)

    1996-12-01

    In this project four sintering mechanisms have been studied, i.e., partial melting with a viscous liquid, partial melting with a non-viscous liquid, chemical reaction sintering and solid state sintering. The work has aimed at improving the understanding of ash sintering mechanisms and quantifying their role in combustion and gasification. The work has been oriented in particular on the understanding of biomass ash behavior. The work has not directly focused on any specific technical application. However, results can also be applied on other fuels such as brown coal, petroleum coke, black liquor and different types of wastes (PDF, RDF, MSW). In one part of study the melting behavior was calculated for ten biomass ashes and compared with lab measurements of sintering tendencies. The comparison showed that the T{sub 15} temperatures, i.e. those temperatures at which the ashes contained 15 % molten phase, correlated fairly well with the temperature at which the sintering measurements detected sintering. This suggests that partial melting can be predicted fairly accurate for some ashes already with the today existing thermodynamic calculation routines. In some cases, however the melting calculations did not correlate with the detected sintering temperatures. In a second part detailed measurements on ash behavior was conducted both in a semi full scale CFB and a lab scale FBC. Ashes and deposits were collected and analyzed in several different ways. These analyses show that the ash chemistry shifts radically when the fuel is shifted. Fuels with silicate based ashes behaved totally different than those with an oxide or salt based ash. The chemistry was also affected by fuel blending. The ultimate goal has been to be able to predict the ash thermal behavior during biomass thermal conversion, using the fuel and ash elemental analyses and a few operational key parameters as the only input data. This goal has not yet today been achieved. (author)

  11. Potential fly-ash utilization in agriculture: A global review

    Institute of Scientific and Technical Information of China (English)

    Manisha Basu; Manish Pande; P.B.S. Bhadoria; S.C. Mahapatra

    2009-01-01

    Though in last four decades various alternate energy sources have come into the limelight, the hyperbolic use of coal as a prime energy source cannot be counterbalanced. Disposal of high amount of fly-ash from thermal power plants absorbs huge amount of water, energy and land area by ash ponds. In order to meet the growing energy demand, various environmental, economic and social problems associated with the disposal of fly-ash would continue to increase. Therefore, fly-ash management would remain a great concern of the century. Fly-ash has great potentiality in agriculture due to its efficacy in modification of soil health and crop performance. The high concentration of elements (K, Na, Zn, Ca, Mg and Fe) in fly-ash increases the yield of many agricultural crops. But compared to other sectors, the use of fly-ash in agriculture is limited. An exhaustive review of numerous studies of last four decades took place in this paper, which systematically covers the importance, scope and apprehension regarding utilization of fly-ash in agriculture. The authors concluded that though studies have established some solutions to handle the problems of radioactivity and heavy metal content in flyash, long-term confirmatory research and demonstration are necessary. This paper also identified some areas, like proper handling of dry ash in plants as well as in fields, ash pond management (i.e., faster decantation, recycling of water, vertical expansion rather than horizontal), monitoring of soil health, crop quality, and fate of fly-ash in time domain, where research thrust is required. Agricultural lime application contributes to global warming as Intergovernmental Panel on Climate Change (IPCC) assumes that all the carbon in agricultural lime is finally released as CO2to the atmosphere. It is expected that use of fly-ash instead of lime in agriculture can reduce net CO2emission, thus reduce global warming also.

  12. Recovering germanium from coal ash by chlorination with ammonium chloride

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new process of enriching germanium from coal ash was developed. The process involves in mixing the coal ash and ammonium chloride and then roasting the mixture to produce germanium chloride that is then absorbed by dilute hydrochloric acid and hydrolyzed to germanium oxide. The germanium recovery reached to 80.2% at the optimum condition: mass ratio of NH4Cl/coal ash is 0.15, roasting temperature 400℃ and roasting time 90 min.

  13. Reuse of Woody Biomass Ash Waste in Cementitious Materials

    OpenAIRE

    Ukrainczyk, N.; Vrbos, N.; Koenders, E.A.B.

    2016-01-01

    There is an increased interest in the reuse of ash waste from biomass combustion, being a sustainable source of energy. This paper investigates the partial replacement of cement and sand in building materials with fly ash waste generated from combustion of woody biomass waste. The results show that the ash widens the particle size distribution of cement and has minerals complementary to portland cement, thus justifying its application as cement replacement, but with a relatively high amoun...

  14. Improved prediction and tracking of volcanic ash clouds

    Science.gov (United States)

    Webley, P.; Mastin, L.

    2009-01-01

    During the past 30??years, more than 100 airplanes have inadvertently flown through clouds of volcanic ash from erupting volcanoes. Such encounters have caused millions of dollars in damage to the aircraft and have endangered the lives of tens of thousands of passengers. In a few severe cases, total engine failure resulted when ash was ingested into turbines and coating turbine blades. These incidents have prompted the establishment of cooperative efforts by the International Civil Aviation Organization and the volcanological community to provide rapid notification of eruptive activity, and to monitor and forecast the trajectories of ash clouds so that they can be avoided by air traffic. Ash-cloud properties such as plume height, ash concentration, and three-dimensional ash distribution have been monitored through non-conventional remote sensing techniques that are under active development. Forecasting the trajectories of ash clouds has required the development of volcanic ash transport and dispersion models that can calculate the path of an ash cloud over the scale of a continent or a hemisphere. Volcanological inputs to these models, such as plume height, mass eruption rate, eruption duration, ash distribution with altitude, and grain-size distribution, must be assigned in real time during an event, often with limited observations. Databases and protocols are currently being developed that allow for rapid assignment of such source parameters. In this paper, we summarize how an interdisciplinary working group on eruption source parameters has been instigating research to improve upon the current understanding of volcanic ash cloud characterization and predictions. Improved predictions of ash cloud movement and air fall will aid in making better hazard assessments for aviation and for public health and air quality. ?? 2008 Elsevier B.V.

  15. 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.

  16. Chemical-Looping Combustion and Gasification of Coals and Oxygen Carrier Development: A Brief Review

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2015-09-01

    Full Text Available Chemical-looping technology is one of the promising CO2 capture technologies. It generates a CO2 enriched flue gas, which will greatly benefit CO2 capture, utilization or sequestration. Both chemical-looping combustion (CLC and chemical-looping gasification (CLG have the potential to be used to generate power, chemicals, and liquid fuels. Chemical-looping is an oxygen transporting process using oxygen carriers. Recently, attention has focused on solid fuels such as coal. Coal chemical-looping reactions are more complicated than gaseous fuels due to coal properties (like mineral matter and the complex reaction pathways involving solid fuels. The mineral matter/ash and sulfur in coal may affect the activity of oxygen carriers. Oxygen carriers are the key issue in chemical-looping processes. Thermogravimetric analysis (TGA has been widely used for the development of oxygen carriers (e.g., oxide reactivity. Two proposed processes for the CLC of solid fuels are in-situ Gasification Chemical-Looping Combustion (iG-CLC and Chemical-Looping with Oxygen Uncoupling (CLOU. The objectives of this review are to discuss various chemical-looping processes with coal, summarize TGA applications in oxygen carrier development, and outline the major challenges associated with coal chemical-looping in iG-CLC and CLOU.

  17. 75 FR 2923 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2010-01-19

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee Meeting. SUMMARY: FMCSA announces that its Motor Carrier Safety Advisory Committee (MCSAC)...

  18. 75 FR 72863 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2010-11-26

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration, DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee Meeting. SUMMARY: FMCSA announces that the Agency's Motor Carrier Safety Advisory Committee...

  19. 76 FR 12214 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2011-03-04

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration, DOT. ACTION: Notice: Announcement of Motor Carrier Safety Advisory Committee meeting; request for comment. SUMMARY: The Federal Motor Carrier Safety...

  20. 75 FR 29384 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2010-05-25

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee meeting. SUMMARY: FMCSA announces that its Motor Carrier Safety Advisory Committee (MCSAC)...